WO2010067700A1 - Polarizing plate and liquid crystal display device using same - Google Patents

Polarizing plate and liquid crystal display device using same Download PDF

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Publication number
WO2010067700A1
WO2010067700A1 PCT/JP2009/069774 JP2009069774W WO2010067700A1 WO 2010067700 A1 WO2010067700 A1 WO 2010067700A1 JP 2009069774 W JP2009069774 W JP 2009069774W WO 2010067700 A1 WO2010067700 A1 WO 2010067700A1
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group
film
carbon atoms
mass
anisotropic layer
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PCT/JP2009/069774
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French (fr)
Japanese (ja)
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伸夫 久保
隆 建部
瀧本　正高
梅田　博紀
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コニカミノルタオプト株式会社
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Publication of WO2010067700A1 publication Critical patent/WO2010067700A1/en

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    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/133528—Polarisers
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/30—Polarising elements
    • G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
    • G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
    • G02B5/3041—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks
    • G02B5/305—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks including organic materials, e.g. polymeric layers
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F2413/00—Indexing scheme related to G02F1/13363, i.e. to birefringent elements, e.g. for optical compensation, characterised by the number, position, orientation or value of the compensation plates
    • G02F2413/02—Number of plates being 2

Definitions

  • the present invention relates to a polarizing plate and a liquid crystal display device using the same. Specifically, the present invention relates to a polarizing plate that is durable against changes in environmental conditions such as temperature and humidity and has improved adhesion between a polarizer and a protective film. The present invention also relates to a wide viewing angle liquid crystal display device using the same to improve front contrast unevenness.
  • a liquid crystal display device As a liquid crystal display device, a liquid crystal display device using a so-called in-plane switching (IPS) mode in which a lateral electric field excellent in viewing angle characteristics is applied to the liquid crystal, or a liquid crystal having a negative dielectric anisotropy is vertically aligned.
  • IPS in-plane switching
  • VA vertical alignment
  • Patent Document 1 a retardation layer formed by vertically aligning with an optical compensation sheet is provided on a support as an optically anisotropic layer, and by using an additive in the layer, not only a viewing angle but also a retardation is provided. Techniques have also been proposed for improving screen unevenness due to unevenness.
  • Patent Document 2 proposes a technique that defines the characteristics of a cellulose ester film serving as a support for providing an anisotropic layer.
  • the present invention has been made in view of the above-mentioned problems and situations, and its solution is durable against changes in environmental conditions such as temperature and humidity, and improved adhesion between the polarizer and the protective film. It is to provide a polarizing plate, and to provide a liquid crystal display device having a wide viewing angle in which front contrast unevenness is improved using the polarizing plate.
  • the present inventors have determined in-plane and thickness-direction retardation and moisture permeability of each of the optical films constituting the first and second optically anisotropic layers. The inventors have found that it is effective to control within a certain condition range, and have completed the present invention.
  • a polarizing plate having at least a first optical anisotropic layer and a second optical anisotropic layer, in the order of adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic layer / polarizer And a polarizing plate characterized by satisfying the following requirements (i) to (iii): (I)
  • the first optically anisotropic layer is an acrylic resin-containing film
  • the in-plane retardation Ro (1) is in the range of ⁇ 40 to 20 nm
  • the thickness direction retardation Rt ( 1) is in the range of ⁇ 400 to ⁇ 80 nm.
  • the second optically anisotropic layer is a film composed of a cellulose ester resin and has a refractive index of nx>ny> nz, and an in-plane retardation Ro (2) of 20 to 150 nm. And retardation Rt (2) in the thickness direction is in the range of 100 to 300 nm.
  • the moisture permeability of the film constituting the first optical anisotropic layer is in the range of 20 to 600 g / m 2 ⁇ 24 h, and the moisture permeability of the film constituting the second optical anisotropic layer is 600 to 1500 g. / M 2 ⁇ 24h.
  • the refractive indexes of the first optical anisotropic layer and the second optical anisotropic layer are defined by the following nx, ny, and nz
  • Ro (1) (nx ⁇ ny) ⁇ d
  • Rt (1) ((nx + ny) / 2 ⁇ nz) ⁇ d
  • Ro (2) (nx ⁇ ny) ⁇ d
  • Rt (2) ((nx + ny) / 2 ⁇ nz) ⁇ d
  • nx is the refractive index in the width direction in the plane of the optically anisotropic layer
  • ny is the film forming or conveying direction in the plane of the optically anisotropic layer, and is in the direction perpendicular to nx in the plane
  • the refractive index, nz represents the refractive index in the thickness direction of the optically anisotropic layer
  • d represents the thickness (nm) of the optically anisotropic layer
  • a polarizing plate that is durable against changes in environmental conditions such as temperature and humidity and has improved adhesion between the polarizer and the protective film. Further, it is possible to provide a liquid crystal display device having a wide viewing angle with improved front contrast unevenness.
  • the polarizing plate of the present invention is a polarizing plate having at least a first optical anisotropic layer and a second optical anisotropic layer, and is an adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic. It is characterized in that it is configured in the order of a functional layer / polarizer and satisfies the requirements (i) to (iii). This feature is a technical feature common to the inventions according to claims 1 and 2.
  • the second optically anisotropic layer according to the present invention is a film composed of a cellulose ester resin and has a refractive index of nx>ny> nz, and an in-plane retardation Ro (1) of 20 to
  • the retardation Rt (1) in the thickness direction is within the range of 150 nm and the thickness direction retardation Rt (1) is within the range of 100 to 300 nm.
  • the film constituting the second optically anisotropic layer has a moisture permeability of 600 to 1500 g / m 2 ⁇ 24 h at 60 ° C. and 95% RH.
  • the second optically anisotropic layer using a cellulose ester film that satisfies the following requirements.
  • ⁇ Cellulose ester resin used for the second optically anisotropic layer a cellulose ester film substantially made of a specific cellulose ester resin is used as the second optically anisotropic layer.
  • substitution degree 2 to 3 diacetyl cellulose (substitution degree 2) and triacetyl cellulose (substitution degree 3), which are acetyl-substituted celluloses
  • the retardation increasing agent described later can be used as an additive for the cellulose ester resin selected in (1).
  • a film composed of cellulose sell resin having a substituent other than the acetyl group may be used.
  • the cellulose ester is a mixed fatty acid ester of cellulose obtained by substituting the hydroxyl group (hydroxyl group) of cellulose with an acetyl group and an acyl group having 3 or more carbon atoms, and preferably 5 or less carbon atoms,
  • the degree of substitution with a hydroxyl group (hydroxyl group) is preferably a cellulose ester satisfying the following mathematical formulas (I) and (II).
  • a and B represent the substitution degree of the acyl group substituted by the hydroxyl group (hydroxyl group) of cellulose
  • A is the substitution degree of the acetyl group
  • B is the acyl group having 3 to 5 carbon atoms. Is the degree of substitution.
  • two or more different cellulose esters may be mixed and used.
  • the ⁇ -1,4-bonded glucose unit constituting cellulose has free hydroxyl groups (hydroxyl groups) at the 2nd, 3rd and 6th positions.
  • Cellulose ester is a polymer obtained by esterifying some or all of these hydroxyl groups (hydroxyl groups) with acyl groups.
  • the degree of acyl substitution means the proportion of cellulose esterified at each of the 2-position, 3-position and 6-position (100% esterification has a degree of substitution of 1).
  • the sum (A + B) of the substitution degree of A and B of the hydroxyl group (hydroxyl group) is 2.0 to 3.0 as shown in the above formula (I). Yes, preferably 2.2 to 2.9, particularly preferably 2.40 to 2.85. Further, the substitution degree of B is a value exceeding 0, preferably 0.9 or more, particularly preferably 1.3 or more, as shown in the above formula (II).
  • B is preferably the substitution degree of the 6-position hydroxyl group (hydroxyl group), more preferably 30% or more is the substitution degree of the 6-position hydroxyl group (hydroxyl group), and 31% or more is the substitution degree. More preferably, 32% or more is preferably the substitution degree of the 6-position hydroxyl group (hydroxyl group).
  • the sum of the substitution degrees of A and B in the 6-position hydroxyl group (hydroxyl group) of the cellulose ester is preferably 0.75 or more, more preferably 0.80 or more, and particularly preferably 0.85 or more.
  • These cellulose ester films can produce a solution for preparing a film having preferable solubility and filterability, and a good solution can be produced even in a non-chlorine organic solvent. Furthermore, it is possible to prepare a solution having a low viscosity and good filterability.
  • the acyl group having 3 to 5 carbon atoms may be an aliphatic group or an aromatic hydrocarbon group and is not particularly limited.
  • cellulose alkylcarbonyl esters alkenylcarbonyl esters, aromatic carbonyl esters, aromatic alkylcarbonyl esters, and the like, each of which may have a further substituted group.
  • These preferred B include propionyl, butanoyl, pentanoyl, hexanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, hexadecanoyl, octadecanoyl, i-butanoyl, t-butanoyl, cyclohexanecarbonyl, oleoyl, benzoyl , Naphthylcarbonyl, cinnamoyl group and the like.
  • propionyl, butanoyl, dodecanoyl, octadecanoyl, t-butanoyl, oleoyl, benzoyl, naphthylcarbonyl, cinnamoyl group and the like are preferable.
  • Particularly preferred are propionyl and butanoyl groups.
  • the degree of substitution B is preferably 0.3 or more, more preferably 0.4 to 2.0 or less, further preferably 0.5 to 1.5, and particularly preferably 0.6 to 1.3. .
  • substitution degree B By setting the substitution degree B within this range, it is possible to suppress physical deformation accompanying a decrease in Tg during high temperature storage and changes in optical properties during high humidity storage.
  • cellulose ester used in the present invention include cellulose acetate propionate and cellulose acetate butyrate.
  • the degree of substitution of the acetyl group, propionyl group and / or butyl group can be determined by measurement according to ASTM: D-817-96 (test method for cellulose acetate etc.) and calculation.
  • a cellulose raw material such as cotton linter or wood pulp is pretreated with an appropriate amount of acetic acid, and is then esterified by introducing it into a pre-cooled carboxylated mixed solution.
  • the total degree of acyl substitution at the 2nd, 3rd and 6th positions is approximately 3.00).
  • the carboxylated mixed solution generally contains acetic acid as a solvent, carboxylic anhydride as an esterifying agent, and sulfuric acid as a catalyst.
  • the carboxylic anhydride is usually used in a stoichiometric excess over the sum of the cellulose that reacts with it and the water present in the system.
  • a neutralizing agent for example, calcium, magnesium, iron, aluminum or zinc
  • carboxylic anhydride for example, calcium, magnesium, iron, aluminum or zinc
  • a neutralizing agent for example, calcium, magnesium, iron, aluminum or zinc
  • the obtained complete cellulose ester is saponified and aged by maintaining it at 50 to 90 ° C. in the presence of a small amount of an acetylation reaction catalyst (generally, remaining sulfuric acid) to obtain a desired degree of acyl substitution and degree of polymerization.
  • an acetylation reaction catalyst generally, remaining sulfuric acid
  • the catalyst remaining in the system is completely neutralized using the neutralizing agent as described above, or the cellulose in water or dilute sulfuric acid without neutralization.
  • the specific cellulose ester can be obtained by introducing an ester solution (or by adding water or dilute sulfuric acid into the cellulose ester solution) to separate the cellulose ester, and performing washing and stabilization treatment. .
  • the polymer component constituting the film is preferably substantially composed of the specific cellulose ester described above. “Substantially” means 55% by mass or more (preferably 70% by mass or more, more preferably 80% by mass or more) of the polymer component.
  • the cellulose ester is preferably used in the form of particles. 90% by mass or more of the particles used preferably have a particle size of 0.5 to 5 mm. Further, it is preferable that 50% by mass or more of the particles to be used have a particle diameter of 1 to 4 mm.
  • the cellulose ester particles preferably have a shape as close to a sphere as possible.
  • the polymerization degree of the cellulose ester preferably used in the present invention is a viscosity average polymerization degree, preferably 200 to 700, more preferably 250 to 550, still more preferably 250 to 400, and particularly preferably 250 to 350.
  • the average degree of polymerization can be measured by the intrinsic viscosity method of Uda et al. (Kazuo Uda, Hideo Saito, “Journal of Textile Society”, 1962, Vol. 18, No. 1, pp. 105-120). Further details are described in JP-A-9-95538.
  • the average molecular weight (degree of polymerization) is increased, but the viscosity is lower than that of a normal cellulose ester. Therefore, the cellulose ester from which the low molecular component is removed is useful.
  • a cellulose ester having a small amount of low molecular components can be obtained by removing low molecular components from a cellulose ester synthesized by an ordinary method.
  • the removal of low molecular components can be carried out by washing the cellulose ester with a suitable organic solvent.
  • the amount of sulfuric acid catalyst in the acetylation reaction is preferable to adjust the amount of sulfuric acid catalyst in the acetylation reaction to 0.5 to 25 parts by mass with respect to 100 parts by mass of the cellulose ester.
  • the amount of the sulfuric acid catalyst is within the above range, a cellulose ester that is preferable in terms of molecular weight distribution (uniform molecular weight distribution) can be synthesized.
  • the water content is preferably 2% by mass or less, more preferably 1% by mass or less, and particularly 0.7% by mass or less.
  • cellulose ester contains water and is known to have a water content of 2.5 to 5% by mass. In order to make the moisture content of a cellulose ester into the said range, it is necessary to dry, The method is not specifically limited.
  • the cellulose ester film according to the present invention can be obtained by preparing a cellulose ester solution in which the specific cellulose ester and, if necessary, an additive are dissolved in an organic solvent, and forming the film using the solution. it can.
  • Additives that can be added to the cellulose ester solution include, for example, plasticizers, ultraviolet absorbers, deterioration inhibitors, retardation (optical anisotropy) increasing agents, retardation (optical anisotropy) reducing agents, and wavelength dispersion. Examples thereof include regulators, fine particles, dyes, peeling accelerators and infrared absorbers.
  • a retardation increasing agent is used. Moreover, it is preferable to use at least one of a plasticizer, an ultraviolet absorber, a dye and a peeling accelerator.
  • UV absorbers of 20 ° C. or lower and 20 ° C. or higher can be mixed and used, and plasticizers can also be mixed and used, for example, as described in JP-A-2001-151901.
  • UV absorber any type can be selected according to the purpose, and a salicylic acid ester-based, benzophenone-based, benzotriazole-based, benzoate-based, cyanoacrylate-based, nickel complex-based absorber or the like is used. Preferred are benzophenone series, benzotriazole series, and salicylic acid ester series.
  • benzophenone ultraviolet absorbers examples include 2,4-dihydroxybenzophenone, 2-hydroxy-4-acetoxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2′-di-hydroxy-4-methoxybenzophenone, 2, 2′-di-hydroxy-4,4′-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2-hydroxy-4- (2-hydroxy-3- And methacryloxy) propoxybenzophenone.
  • benzotriazole ultraviolet absorber 2 (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2 (2′-hydroxy-5′-tert-butylphenyl) ) Benzotriazole, 2 (2′-hydroxy-3 ′, 5′-di-tert-amylphenyl) benzotriazole, 2 (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5 And chlorobenzotriazole, 2 (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, and the like.
  • salicylic acid ester group examples include phenyl salicylate, p-octylphenyl salicylate, p-tert-butylphenyl salicylate, and the like.
  • UV absorbers in particular, 2-hydroxy-4-methoxybenzophenone, 2,2′-di-hydroxy-4,4′-methoxybenzophenone, 2 (2′-hydroxy-3′-tert-butyl- 5'-methylphenyl) -5-chlorobenzotriazole, 2 (2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2 (2'-hydroxy-3 ', 5'-di-tert-amylphenyl) ) Benzotriazole, 2 (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5-chlorobenzotriazole is particularly preferred.
  • the ultraviolet absorbent for liquid crystal is preferably one that is excellent in the ability to absorb ultraviolet light having a wavelength of 370 nm or less from the viewpoint of preventing deterioration of the liquid crystal and that has little absorption of visible light having a wavelength of 400 nm or more from the viewpoint of liquid crystal display properties.
  • Particularly preferred ultraviolet absorbers are the benzotriazole compounds, benzophenone compounds and salicylic acid ester compounds mentioned above.
  • a benzotriazole-based compound is preferable because unnecessary coloring with respect to the cellulose ester is small.
  • JP-A-60-235852 JP-A-3-199201, JP-A-5-194789, JP-A-5-271471, JP-A-6-107854, JP-A-6-118233, JP-A-6-
  • the compounds described in JP-A Nos. 130226, 6-148430, 7-11055, 7-11056, 8-29619, 8-239509, and JP-A-2000-204173 can also be used. it can.
  • the addition amount of the ultraviolet absorber is preferably 0.001 to 5% by mass, more preferably 0.01 to 1% by mass with respect to the cellulose ester. If the addition amount is less than 0.001% by mass, the effect of addition cannot be sufficiently exhibited. If the addition amount exceeds 5% by mass, the ultraviolet absorber may bleed out to the film surface.
  • the ultraviolet absorber may be added simultaneously with the dissolution of the cellulose ester, or may be added to the dope after dissolution.
  • a mode in which an ultraviolet absorbent solution is added to the dope immediately before casting using a static mixer or the like is preferable because the spectral absorption characteristics can be easily adjusted.
  • the deterioration inhibitor can prevent cellulose triacetate and the like from deteriorating and decomposing.
  • deterioration inhibitors include butylamine, hindered amine compounds (Japanese Patent Laid-Open No. 8-325537), guanidine compounds (Japanese Patent Laid-Open No. 5-271471), benzotriazole-based UV absorbers (Japanese Patent Laid-Open No. 6-235819), and benzophenone-based compounds.
  • UV absorbers JP-A-6-118233.
  • the plasticizer is preferably a phosphate ester or a carboxylic acid ester.
  • the plasticizer may be triphenyl phosphate (TPP), tricresyl phosphate (TCP), cresyl diphenyl phosphate, octyl diphenyl phosphate, biphenyl diphenyl phosphate (BDP), trioctyl phosphate, tributyl phosphate, dimethyl phthalate (DMP) ), Diethyl phthalate (DEP), dibutyl phthalate (DBP), dioctyl phthalate (DOP), diphenyl phthalate (DPP), diethyl hexyl phthalate (DEHP), triethyl O-acetylcitrate (OACTE), tributyl O-acetylcitrate ( OACTB), acetyl triethyl citrate, acetyl tributyl citrate,
  • the plasticizer is preferably (di) pentaerythritol esters, glycerol esters, or diglycerol esters.
  • peeling accelerator examples include citric acid ethyl esters. Further, infrared absorbers are described in, for example, JP-A No. 2001-194522.
  • a dye for adjusting the hue may be added.
  • the content of the dye is preferably from 10 to 1000 ppm, more preferably from 50 to 500 ppm, by mass ratio with respect to the cellulose ester.
  • These compounds may be added together with the cellulose ester and the solvent during the preparation of the cellulose ester solution, or may be added during or after the solution preparation. Moreover, you may add to the ultraviolet absorber liquid added in-line.
  • the dye used in the present invention is preferably a compound represented by the following general formula (1) or (2).
  • R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are each a hydrogen atom, hydroxyl group (hydroxyl group), aliphatic group, aromatic group, complex Ring group, halogen atom, cyano group, nitro group, —COR 9 , —COOR 9 , —NR 9 R 10 , —NR 10 COR 11 , —NR 10 SO 2 R 11 , —CONR 9 R 10 , —SO 2 NR 9 R 10, -COR 11, -SO 2 R 11, -OCOR 11, -NR 9 CONR 10 R 11, represents a -CONHSO 2 R 11 or -SO 2 NHCOR 11, R 9 and R 10 are each a hydrogen atom, R 11 represents an aliphatic group, an aromatic group or a heterocyclic group, and R 11 represents an aliphatic group, an aromatic group or a heterocyclic group.
  • R 9 and R 10 may be linked to form a 5- or 6-membere
  • R 21 , R 23 and R 24 are each a hydrogen atom, a hydroxyl group (hydroxyl group), a nitro group, a cyano group, an aliphatic group, an aromatic group, —COR 29 , —COOR 29 , —NR 29.
  • R 30 represents —NR 30 COR 31 or —NR 30 SO 2 R 31
  • R 22 represents an aliphatic group or an aromatic group
  • R 29 and R 30 represent R 9 and R 10 in the general formula (1), respectively.
  • R 31 is synonymous with R 11 in the general formula (1).
  • one or more of R 21 , R 22 , R 23 and R 24 are groups other than hydrogen.
  • the aliphatic group represented by R 1 to R 11 is an alkyl group having 1 to 20 carbon atoms (for example, methyl, ethyl, n-butyl, isopropyl, 2-ethylhexyl, n-decyl, n-octadecyl), carbon number 1 to 20 cycloalkyl groups (for example, cyclopentyl, cyclohexyl) or allyl groups, and substituents [for example, halogen atom (for example, F, Cl, Br, I), hydroxyl group (hydroxyl group), cyano group, nitro group , Carboxylic acid group, aryl group having 6 to 10 carbon atoms (for example, phenyl, naphthyl), amino group having 0 to 20 carbon atoms (for example, NH 2 , NHCH 3 , N (C 2 H 5 ) 2 , N (C 4 H 9 ) 2 , N (C 8 H 17 )
  • the aromatic group represented by R 1 to R 11 represents an aryl group having 6 to 10 carbon atoms (for example, phenyl or naphthyl), and a substituent [for example, the above-mentioned aliphatic group may have a substituent
  • an alkyl group having 1 to 20 carbon atoms for example, methyl, ethyl, butyl, t-butyl, octyl, etc.
  • the heterocyclic group represented by R 1 to R 11 represents a 5- or 6-membered heterocyclic ring (for example, pyridine, piperidine, morpholine, pyrrolidine, pyrazole, pyrazolidine, pyrazoline, pyrazolone, benzoxazole) and a substituent (for example, Each group mentioned as a substituent which the above-mentioned aromatic group may have may have.
  • Examples of the 5- or 6-membered ring formed by connecting R 9 and R 10 include a morpholine ring, a piperidine ring, and a pyrrolidine ring.
  • the ring formed by connecting R 1 and R 2 or R 2 and R 3 is preferably a 5- or 6-membered ring (for example, a benzene ring or a phthalimide ring).
  • the aliphatic group represented by R 21 to R 24 has the same meaning as the aliphatic group represented by R 1 to R 11 in the general formula (1), and the aromatic group represented by R 21 to R 24 is a general group. It has the same meaning as the aromatic group represented by R 1 to R 11 in Formula (1).
  • the timing of adding these additives may be any timing in the dope preparation process, but a process of adding additives to the final preparation process of the dope preparation process may be performed. Furthermore, the amount of each material added is not particularly limited as long as the function is manifested.
  • the type and amount of additives in each layer may be different.
  • the glass transition point Tg of the cellulose ester film measured with a dynamic viscoelasticity measuring device is 70 to 150 ° C. More preferably, the glass transition point Tg is preferably 80 to 135 ° C.
  • the cellulose ester film according to the present invention preferably has a glass transition point Tg in the above range from the viewpoint of process suitability for polarizing plate processing and liquid crystal display device assembly.
  • the retardation is adjusted so that the optical anisotropy of the cellulose ester film can be used as the second optical anisotropic layer.
  • a retardation increasing agent it is preferable to use a retardation increasing agent.
  • the retardation increasing agent increases the value of Rt by 0.11 or more per 1 micron film thickness by adding 1 part by mass with respect to 100 parts by mass of the polymer component containing cellulose ester.
  • the retardation is increased by 0.2 or more per micron of film thickness, more preferably 0.3 or more per micron of film thickness.
  • Examples of the retardation increasing agent that can be used in the present invention include those composed of rod-shaped or discotic compounds.
  • a compound having at least two aromatic rings can be used as the rod-like or discotic compound.
  • the addition amount of the retardation increasing agent composed of the rod-like compound is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the polymer component containing the cellulose ester. preferable.
  • the disc-shaped retardation increasing agent is preferably used in the range of 0.05 to 30 parts by mass, and in the range of 0.1 to 20 parts by mass with respect to 100 parts by mass of the polymer component containing the cellulose ester. More preferably, it is more preferably used in the range of 0.2 to 15 parts by mass, and most preferably in the range of 0.5 to 10 parts by mass.
  • the discotic compound is superior to the rod-like compound in terms of Rt retardation expression, it is preferably used when a particularly large Rt retardation is required.
  • Two or more types of retardation increasing agents may be used in combination.
  • the retardation increasing agent composed of a rod-like or discotic compound preferably has maximum absorption in the wavelength region of 250 to 400 nm, and preferably has substantially no absorption in the visible region.
  • the discotic compound will be described.
  • a compound having at least two aromatic rings can be used.
  • the “aromatic ring” includes an aromatic hetero ring in addition to an aromatic hydrocarbon ring.
  • the aromatic hydrocarbon ring is particularly preferably a 6-membered ring (that is, a benzene ring).
  • the aromatic heterocycle is generally an unsaturated heterocycle.
  • the aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring.
  • Aromatic heterocycles generally have the most double bonds.
  • a nitrogen atom, an oxygen atom and a sulfur atom are preferable, and a nitrogen atom is particularly preferable.
  • aromatic heterocycles include furan ring, thiophene ring, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, pyrazole ring, furazane ring, triazole ring, pyran ring, pyridine ring , Pyridazine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring.
  • aromatic ring benzene ring, furan ring, thiophene ring, pyrrole ring, oxazole ring, thiazole ring, imidazole ring, triazole ring, pyridine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring are preferable, In particular, 1,3,5-triazine ring is preferably used.
  • a compound disclosed in JP-A No. 2001-166144 is preferably used as the discotic compound.
  • the number of aromatic rings contained in the discotic compound is preferably 2 to 20, more preferably 2 to 12, still more preferably 2 to 8, and most preferably 2 to 6. preferable.
  • the bonding relationship between two aromatic rings can be classified into (a) when forming a condensed ring, (b) when directly connecting with a single bond, and (c) when connecting via a linking group (for aromatic rings). , Spiro bonds cannot be formed).
  • the bond relationship may be any of (a) to (c).
  • condensed ring examples include an indene ring, a naphthalene ring, an azulene ring, a fluorene ring, a phenanthrene ring, an anthracene ring, an acenaphthylene ring, a biphenylene ring, a naphthacene ring, Pyrene ring, indole ring, isoindole ring, benzofuran ring, benzothiophene ring, indolizine ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring, purine ring, indazole ring, chromene ring, quinoline ring, isoquinoline Ring, quinolidine ring, quinazoline ring, cinnoline ring, quinoxaline ring, phthalazine
  • the single bond (b) is preferably a bond between carbon atoms of two aromatic rings.
  • Two aromatic rings may be bonded by two or more single bonds to form an aliphatic ring or a non-aromatic heterocyclic ring between the two aromatic rings.
  • the linking group in (c) is also preferably bonded to carbon atoms of two aromatic rings.
  • the linking group is preferably an alkylene group, an alkenylene group, an alkynylene group, —CO—, —O—, —NH—, —S—, or a combination thereof. Examples of linking groups composed of combinations are shown below. In addition, the relationship between the left and right in the following examples of the linking group may be reversed.
  • substituents include halogen atoms (F, Cl, Br, I), hydroxyl groups, carboxyl groups, cyano groups, amino groups, nitro groups, sulfo groups, carbamoyl groups, sulfamoyl groups, ureido groups, alkyl groups, alkenyls.
  • alkynyl group alkynyl group, aliphatic acyl group, aliphatic acyloxy group, alkoxy group, alkoxycarbonyl group, alkoxycarbonylamino group, alkylthio group, alkylsulfonyl group, aliphatic amide group, aliphatic sulfonamido group, aliphatic substituted amino group
  • the number of carbon atoms in the alkyl group is preferably 1-8.
  • a chain alkyl group is preferable to a cyclic alkyl group, and a linear alkyl group is particularly preferable.
  • the alkyl group may further have a substituent (eg, hydroxy group, carboxy group, alkoxy group, alkyl-substituted amino group).
  • alkyl groups include methyl, ethyl, n-butyl, n-hexyl, 2-hydroxyethyl, 4-carboxybutyl, 2-methoxyethyl and 2-methoxyethyl.
  • a diethylaminoethyl group is included.
  • the alkenyl group preferably has 2 to 8 carbon atoms.
  • a chain alkenyl group is preferable to a cyclic alkenyl group, and a linear alkenyl group is particularly preferable.
  • the alkenyl group may further have a substituent. Examples of the alkenyl group include a vinyl group, an allyl group, and a 1-hexenyl group.
  • the number of carbon atoms of the alkynyl group is preferably 2-8.
  • a chain alkynyl group is preferable to a cyclic alkynyl group, and a linear alkynyl group is particularly preferable.
  • the alkynyl group may further have a substituent. Examples of the alkynyl group include ethynyl group, 1-butynyl group and 1-hexynyl group.
  • the number of carbon atoms in the aliphatic acyl group is preferably 1-10.
  • Examples of the aliphatic acyl group include an acetyl group, a propanoyl group, and a butanoyl group.
  • the number of carbon atoms in the aliphatic acyloxy group is preferably 1-10.
  • Examples of the aliphatic acyloxy group include an acetoxy group.
  • the number of carbon atoms of the alkoxy group is preferably 1-8.
  • the alkoxy group may further have a substituent (eg, alkoxy group).
  • substituents eg, alkoxy group.
  • Examples of the alkoxy group (including a substituted alkoxy group) include a methoxy group, an ethoxy group, a butoxy group, and a methoxyethoxy group.
  • the number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 10.
  • Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group.
  • the number of carbon atoms of the alkoxycarbonylamino group is preferably 2 to 10.
  • Examples of the alkoxycarbonylamino group include a methoxycarbonylamino group and an ethoxycarbonylamino group.
  • the number of carbon atoms of the alkylthio group is preferably 1-12.
  • Examples of the alkylthio group include a methylthio group, an ethylthio group, and an octylthio group.
  • the number of carbon atoms of the alkylsulfonyl group is preferably 1-8.
  • Examples of the alkylsulfonyl group include a methanesulfonyl group and an ethanesulfonyl group.
  • the number of carbon atoms in the aliphatic amide group is preferably 1-10.
  • Examples of the aliphatic amide group include an acetamide group.
  • the number of carbon atoms in the aliphatic sulfonamide group is preferably 1-8.
  • Examples of the aliphatic sulfonamido group include a methanesulfonamido group, a butanesulfonamido group and an n-octanesulfonamido group.
  • the number of carbon atoms of the aliphatic substituted amino group is preferably 1-10.
  • Examples of the aliphatic substituted amino group include a dimethylamino group, a diethylamino group, and a 2-carboxyethylamino group.
  • the number of carbon atoms in the aliphatic substituted carbamoyl group is preferably 2 to 10.
  • Examples of the aliphatic substituted carbamoyl group include a methylcarbamoyl group and a diethylcarbamoyl group.
  • the number of carbon atoms of the aliphatic substituted sulfamoyl group is preferably 1-8.
  • Examples of the aliphatic substituted sulfamoyl group include a methylsulfamoyl group and a diethylsulfamoyl group.
  • the number of carbon atoms of the aliphatic substituted ureido group is preferably 2 to 10.
  • Examples of the aliphatic substituted ureido group include a methylureido group.
  • non-aromatic heterocyclic groups examples include piperidino groups and morpholino groups.
  • the molecular weight of the retardation increasing agent comprising a discotic compound is preferably 300 to 800.
  • a rod-shaped compound having a linear molecular structure in addition to the above-mentioned discotic compound, a rod-shaped compound having a linear molecular structure can also be preferably used.
  • the linear molecular structure means that the molecular structure of the rod-like compound is linear in the most thermodynamically stable structure.
  • the most thermodynamically stable structure can be obtained by crystal structure analysis or molecular orbital calculation.
  • molecular orbital calculation can be performed using molecular orbital calculation software (eg, WinMOPAC2000, manufactured by Fujitsu Limited) to obtain a molecular structure that minimizes the heat of formation of a compound.
  • the linear molecular structure means that the angle formed by the main chain in the molecular structure is 140 degrees or more in the thermodynamically most stable structure obtained by calculation as described above.
  • Ar 1 -L 1 -Ar 2 In the general formula (3), Ar 1 and Ar 2 each independently represent an aryl group (aromatic hydrocarbon group), a substituted aryl group, an aromatic heterocyclic group or a substituted aromatic heterocyclic group. . An aryl group and a substituted aryl group are more preferable than an aromatic heterocyclic group and a substituted aromatic heterocyclic group.
  • the heterocycle of the aromatic heterocyclic group is generally unsaturated.
  • the aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring.
  • Aromatic hetero rings generally have the most double bonds.
  • a hetero atom a nitrogen atom, an oxygen atom or a sulfur atom is preferable, and a nitrogen atom or a sulfur atom is more preferable.
  • a benzene ring As the aromatic ring of the aromatic group, a benzene ring, a furan ring, a thiophene ring, a pyrrole ring, an oxazole ring, a thiazole ring, an imidazole ring, a triazole ring, a pyridine ring, a pyrimidine ring and a pyrazine ring are preferable, and a benzene ring is particularly preferable. .
  • substituent of the substituted aryl group and the substituted aromatic heterocyclic group examples include a halogen atom (F, Cl, Br, I), a hydroxyl group, a carboxyl group, a cyano group, an amino group, an alkylamino group (eg, methyl).
  • Examples of the substituent of the substituted aryl group and the substituted aromatic heterocyclic group include a halogen atom, a cyano group, a carboxyl group, a hydroxyl group, an amino group, an alkyl-substituted amino group, an acyl group, an acyloxy group, an amide group, an alkoxycarbonyl group, Alkoxy groups, alkylthio groups and alkyl groups are preferred.
  • alkyl moiety of the alkylamino group, alkoxycarbonyl group, alkoxy group, and alkylthio group and the alkyl group may further have a substituent.
  • alkyl moieties and substituents of alkyl groups include halogen atoms, hydroxyl, carboxyl, cyano, amino, alkylamino groups, nitro, sulfo, carbamoyl, alkylcarbamoyl groups, sulfamoyl, alkylsulfamoyl groups, ureido, alkylureido Group, alkenyl group, alkynyl group, acyl group, acyloxy group, acylamino group, alkoxy group, aryloxy group, alkoxycarbonyl group, aryloxycarbonyl group, alkoxycarbonylamino group, alkylthio group, arylthio group, alkylsulfonyl group, amide group And non-aromatic heterocyclic groups.
  • a halogen atom hydroxyl, amino, alkylamino group, acyl group, acyloxy group, acylamino group, alkoxycarbonyl group and alkoxy group are preferable.
  • L 1 is a divalent linking group selected from an alkylene group, an alkenylene group, an alkynylene group, —O—, —CO— and a combination thereof.
  • the alkylene group may have a cyclic structure.
  • cyclic alkylene group cyclohexylene is preferable, and 1,4-cyclohexylene is particularly preferable.
  • chain alkylene group a linear alkylene group is more preferable than a branched alkylene group.
  • the number of carbon atoms of the alkylene group is preferably 1-20, more preferably 1-15, still more preferably 1-10, still more preferably 1-8, and most preferably 1-6. It is.
  • the alkenylene group and the alkynylene group preferably have a chain structure rather than a cyclic structure, and more preferably have a linear structure rather than a branched chain structure.
  • the number of carbon atoms of the alkenylene group and the alkynylene group is preferably 2 to 10, more preferably 2 to 8, further preferably 2 to 6, further preferably 2 to 4, and most preferably 2. (Vinylene or ethynylene).
  • the arylene group preferably has 6 to 20 carbon atoms, more preferably 6 to 16, and still more preferably 6 to 12.
  • the angle formed by Ar 1 and Ar 2 across L 1 is preferably 140 degrees or more.
  • the rod-like compound can be synthesized by a method described in the literature.
  • a rod-like compound represented by the following general formula (4) is used as the retardation increasing agent.
  • the compound represented by the general formula (4) will be described below.
  • R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent
  • R 31 , R 32 , R 33 , R 34 and R 35 each represents an electron donating group
  • R 38 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms.
  • R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent, and the substituent will be described later.
  • the substituent T can be applied.
  • At least one of R 31 , R 32 , R 33 , R 34 and R 35 represents an electron donating group. It is more preferable that one of R 31 , R 33 or R 35 is an electron donating group and R 33 is an electron donating group.
  • the electron donating group means one having Hammet's ⁇ p value of 0 or less. Rev. 91, 165 (1991), those having Hammet's ⁇ p value of 0 or less are preferably applicable, and those having ⁇ 0.85 to 0 are more preferably used. Examples thereof include an alkyl group, an alkoxy group, an amino group, and a hydroxyl group (hydroxyl group).
  • the electron donating group is preferably an alkyl group or an alkoxy group, more preferably an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably carbon atoms). 1 to 4).
  • R 31 is preferably a hydrogen atom or an electron-donating group, more preferably an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), and still more preferably an alkyl group having 1 to 4 carbon atoms or a carbon atom.
  • R 32 is preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), more preferably a hydrogen atom, an alkyl group, or an alkoxy group, still more preferably a hydrogen atom, an alkyl group ( Preferably, it has 1 to 4 carbon atoms, more preferably a methyl group.), An alkoxy group (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms. Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.
  • R 33 is preferably a hydrogen atom or an electron donating group, more preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), and still more preferably an alkyl group or an alkoxy group. Particularly preferably, it is an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms). Most preferred are n-propoxy group, ethoxy group and methoxy group.
  • R 34 is preferably a hydrogen atom or an electron donating group, more preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), and still more preferably a hydrogen atom or a carbon number of 1 to An alkyl group having 4 carbon atoms and an alkoxy group having 1 to 12 carbon atoms (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms). And particularly preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms, and most preferably a hydrogen atom, a methyl group and a methoxy group.
  • R 35 is preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), more preferably a hydrogen atom, an alkyl group, or an alkoxy group, still more preferably a hydrogen atom, an alkyl group ( Preferably, it has 1 to 4 carbon atoms, more preferably a methyl group), an alkoxy group (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably carbon atoms). 1 to 4). Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.
  • R 36 , R 37 , R 39 and R 40 are preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or a halogen atom, more preferably a hydrogen atom or a halogen atom. And more preferably a hydrogen atom.
  • R 38 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms.
  • the group T can be applied.
  • R 38 is preferably an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 2 to 12 carbon atoms.
  • it is an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms, and more preferably an alkoxy group having 1 to 12 carbon atoms (preferably Is 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms, and particularly preferably a methoxy group, an ethoxy group, n-propoxy group, iso-propoxy group and n-butoxy group.
  • R 41 represents an alkyl group.
  • R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent.
  • R 38 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms.
  • R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 38 , R 39 and R 40 are respectively synonymous with those in the general formula (4), and The preferable range is also the same.
  • R 41 represents an alkyl group having 1 to 12 carbon atoms, and the alkyl group represented by R 41 may be linear or branched, and further has a substituent. However, it is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms, still more preferably an alkyl group having 1 to 6 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms (for example, Methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group, and the like.
  • R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent.
  • R 41 represents an alkyl group having 1 to 12 carbon atoms.
  • X represents an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, It represents a 2-12 alkoxycarbonyl group, an acylamino group having 2-12 carbon atoms, a cyano group or a halogen atom.
  • R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 39 , and R 40 are synonymous with those in the general formula (4), and preferred ranges are also included. It is the same.
  • R 41 has the same meaning as that in the general formula (4-A), and the preferred range is also the same.
  • X represents an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or 6 carbon atoms.
  • X is preferably an alkyl group, alkynyl group, aryl group, alkoxy group or aryloxy group, more preferably an aryl group, alkoxy group
  • An aryloxy group more preferably an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms).
  • X is preferably an alkynyl group, an aryl group, an alkoxycarbonyl group, or a cyano group, more preferably an aryl group (preferably Is a cyano group or an alkoxycarbonyl group (preferably 2 to 12 carbon atoms), more preferably an aryl group (preferably an aryl group having 6 to 12 carbon atoms, more preferably a phenyl group).
  • P-cyanophenyl group, and p-methoxyphenyl group an alkoxycarbonyl group (preferably having 2 to 12, more preferably 2 to 6, more preferably 2 to 4, and particularly preferably methoxycarbonyl).
  • Ethoxycarbonyl, n-propoxycarbonyl cyano group, particularly preferably An enyl group, a methoxycarbonyl group, an ethoxycarbonyl group, an n-propoxycarbonyl group, and a cyano group.
  • R 31 , R 32 , R 34 , R 35 , R 41 and X have the same meanings as those in general formula (4-B), and preferred ranges are also the same.
  • R 32 , R 34 and R 35 have the same meanings as those in general formula (4-C), and preferred ranges are also the same.
  • R 51 and R 52 are each independently an alkyl group having 1 to 4 carbon atoms.
  • X 1 is an aryl group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, or a cyano group.
  • R 51 represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, and more preferably an ethyl group or a methyl group.
  • R 52 represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, more preferably an ethyl group or a methyl group, and still more preferably a methyl group.
  • X 1 is an aryl group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, or a cyano group, preferably an aryl group having 6 to 10 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, or a cyano group.
  • R 32 ′ , R 34 ′ and R 35 ′ each independently represent a hydrogen atom or a substituent, and any one of them is a group represented by —OR 43.
  • R 43 is an alkyl group having 1 to 4 carbon atoms.
  • the ranges of substituents represented by R 32 ′ , R 34 ′ and R 35 ′ and preferred ranges thereof are the same as described above.
  • R 51 , R 52 and X 1 have the same meanings as those in formula (4-D), and preferred ranges are also the same.
  • any one of R 32 ′ , R 34 ′ and R 35 ′ is a group represented by —OR 43 (R 43 is an alkyl group having 1 to 4 carbon atoms). ), Preferably R 34 ′ and R 35 ′ are groups represented by —OR 43 , and more preferably R 34 ′ is a group represented by —OR 43 .
  • R 43 represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, more preferably an ethyl group or a methyl group, and still more preferably a methyl group.
  • substituent T examples include an alkyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms, such as methyl, ethyl, iso-propyl, tert-butyl, and n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, etc.), an alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably carbon number).
  • alkyl group preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms, such as methyl, ethyl, iso-propyl, tert-butyl, and n-octyl, n-decyl, n-hexadecyl,
  • alkynyl group preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably carbon number
  • aryl group preferably having 6 to 3 carbon atoms
  • a substituted or unsubstituted amino group preferably having 0 carbon atoms.
  • carbon atoms particularly preferably 0 to 6 carbon atoms, such as amino, methylamino, dimethylamino, diethylamino, dibenzylamino, etc.
  • an alkoxy group preferably carbon 1 to 20, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as methoxy, ethoxy, butoxy, etc.
  • an aryloxy group preferably having 6 to 20 carbon atoms, More preferably, it has 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenyloxy, 2-naphthyloxy and the like.
  • An acyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include acetyl, benzoyl, formyl, and pivaloyl).
  • An alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, etc.), an aryloxycarbonyl group (Preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, particularly preferably 7 to 10 carbon atoms, such as phenyloxycarbonyl), acyloxy group (preferably having 2 to 20 carbon atoms) More preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, such as acetoxy, Examples include benzoyloxy.
  • An acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include acetylamino and benzoylamino), alkoxycarbonylamino group (Preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms such as methoxycarbonylamino), aryloxycarbonylamino group (preferably having carbon number) 7 to 20, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, such as phenyloxycarbonylamino, and the like, and sulfonylamino groups (preferably 1 to 20 carbon atoms, more preferably Has 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms.
  • sulfamoyl groups preferably having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms, such as sulfamoyl, methylsulfamoyl) , Dimethylsulfamoyl, phenylsulfamoyl, etc.
  • a carbamoyl group preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms.
  • carbamoyl Methylcarbamoyl, diethylcarbamoyl, phenylcarbamoyl, etc.
  • an alkylthio group preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as methylthio, Ethylthio etc.
  • arylthio group preferably Has 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenylthio, and the like
  • a sulfonyl group preferably 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as mesyl, tosyl, etc.
  • sulfinyl group preferably 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably Has 1 to 12 carbon atoms, such as
  • ureido, methylureido, phenylureido, etc. phosphoric acid amide groups (preferably having 1 to 20 carbon atoms, More preferably, it has 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include diethyl phosphoric acid amide and phenyl phosphoric acid amide.
  • Hydroxy group mercapto group, halogen atom (eg fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, Heterocyclic group (preferably having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms).
  • halogen atom eg fluorine atom, chlorine atom, bromine atom, iodine atom
  • cyano group eg fluorine atom, chlorine atom, bromine atom, iodine atom
  • sulfo group carboxyl group
  • nitro group hydroxamic acid group
  • sulfino group sulfino group
  • hydrazino group imino group
  • Heterocyclic group preferably having 1 to 30 carbon atoms, more preferably 1 to
  • hetero atom examples include a nitrogen atom, an oxygen atom, a sulfur atom, specifically, for example, imidazolyl, pyridyl, quinolyl, furyl, piperidyl , Morpholino, benzoxazolyl, benzimidazolyl, benzthiazolyl, etc.), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms). For example, trimethylsilyl, triphenylsilyl, etc.) . These substituents may be further substituted.
  • substituents when there are two or more substituents, they may be the same or different. If possible, they may be linked together to form a ring.
  • the compound represented by the general formula (4) can be synthesized by a general ester reaction of a substituted benzoic acid and a phenol derivative, and any reaction may be used as long as it is an ester bond forming reaction.
  • Examples thereof include a method of converting a substituted benzoic acid to an acid halide and then condensing with phenol, a method of dehydrating condensation of a substituted benzoic acid and a phenol derivative using a condensing agent or a catalyst, and the like.
  • Reaction solvents include hydrocarbon solvents (preferably toluene and xylene), ether solvents (preferably dimethyl ether, tetrahydrofuran, dioxane, etc.), ketone solvents, ester solvents, acetonitrile, dimethylformamide, dimethyl Acetamide or the like can be used.
  • reaction solvents may be used alone or in admixture of several kinds, and preferred reaction solvents are toluene, acetonitrile, dimethylformamide, and dimethylacetamide.
  • the reaction temperature is preferably 0 to 150 ° C., more preferably 0 to 100 ° C., further preferably 0 to 90 ° C., and particularly preferably 20 ° C. to 90 ° C.
  • a base either an organic base or an inorganic base may be used, preferably an organic base such as pyridine, tertiary alkylamine (preferably triethylamine, ethyldiisopropyl). Pyramine and the like).
  • organic base such as pyridine, tertiary alkylamine (preferably triethylamine, ethyldiisopropyl). Pyramine and the like).
  • Two or more rod-like compounds having a maximum absorption wavelength ( ⁇ max) shorter than 250 nm in the ultraviolet absorption spectrum of the solution may be used in combination.
  • the fine particles used in the present invention include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, silica Mention may be made of magnesium and calcium phosphates.
  • Fine particles containing silicon are preferable from the viewpoint of reducing turbidity, and silicon dioxide is particularly preferable.
  • the fine particles of silicon dioxide preferably have a primary average particle diameter of 20 nm or less and an apparent specific gravity of 70 g / liter or more.
  • the average primary particle size is as small as 5 to 16 nm because the haze of the film can be lowered.
  • the apparent specific gravity is preferably 90 to 200 g / liter or more, and more preferably 100 to 200 g / liter or more.
  • a larger apparent specific gravity is preferable because a high-concentration dispersion can be produced, and haze and aggregates are improved.
  • the amount used is preferably 0.01 to 0.3 parts by mass with respect to 100 parts by mass of the polymer component containing cellulose ester.
  • These fine particles usually form secondary particles having an average particle diameter of 0.1 to 3.0 ⁇ m, and these fine particles are present in the film as aggregates of primary particles, and 0.1 to 3.0 ⁇ m on the film surface. An unevenness of 3.0 ⁇ m is formed.
  • the secondary average particle diameter is preferably 0.2 ⁇ m to 1.5 ⁇ m, more preferably 0.4 ⁇ m to 1.2 ⁇ m, and most preferably 0.6 ⁇ m to 1.1 ⁇ m.
  • the primary and secondary particle diameters are determined by observing particles in the film with a scanning electron microscope and using the diameter of a circle circumscribing the particles as the particle diameter. Also, 200 particles are observed at different locations, and the average value is taken as the average particle diameter.
  • silicon dioxide fine particles for example, commercially available products such as Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600 (manufactured by Nippon Aerosil Co., Ltd.) can be used.
  • Zirconium oxide fine particles are commercially available under the trade names of Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) and can be used.
  • Aerosil 200V and Aerosil R972V are fine particles of silicon dioxide having a primary average particle diameter of 20 nm or less and an apparent specific gravity of 70 g / liter or more, and the coefficient of friction is maintained while keeping the turbidity of the optical film low. It is particularly preferable because it has a great effect of reducing the effect.
  • a fine particle dispersion liquid prepared by stirring and mixing a solvent and fine particles is prepared in advance, and this fine particle dispersion solution is added to a small amount of a separately prepared cellulose ester solution, stirred and dissolved, and further mixed with the main cellulose ester dope solution.
  • This method is a preferable preparation method in that the dispersibility of the silicon dioxide fine particles is good and the silicon dioxide fine particles are more difficult to reaggregate.
  • adding a small amount of cellulose ester to the solvent and dissolving with stirring add the fine particles to this and disperse with a disperser, and use this as a fine particle additive solution. There is also a method of mixing.
  • the concentration of silicon dioxide when the silicon dioxide fine particles are mixed and dispersed with a solvent or the like is preferably 5 to 30% by mass, more preferably 10 to 25% by mass, Most preferred is 20% by weight.
  • a higher dispersion concentration is preferable because the liquid turbidity with respect to the added amount is lowered, and haze and aggregates are improved.
  • the addition amount of the matting agent in the final cellulose ester dope solution is preferably 0.01 to 1.0 g, more preferably 0.03 to 0.3 g, and most preferably 0.08 to 0.16 g per 1 m 2. preferable.
  • the solvent used is preferably lower alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol and the like. Although it does not specifically limit as solvents other than a lower alcohol, It is preferable to use the solvent used at the time of film forming of a cellulose ester.
  • any of a chlorinated solvent containing a chlorinated organic solvent as a main solvent and a non-chlorinated solvent not containing a chlorinated organic solvent can be used.
  • chlorinated organic solvent is preferably used as the main solvent.
  • the kind of the chlorinated organic solvent is not particularly limited as long as the object can be achieved within a range in which the cellulose ester can be dissolved and solution casting can be performed.
  • chlorinated organic solvents are preferably dichloromethane and chloroform. Particularly preferred is dichloromethane.
  • dichloromethane Particularly preferred is dichloromethane.
  • organic solvent other than the chlorinated organic solvent it is necessary to use at least 50% by mass of dichloromethane in the total amount of the organic solvent.
  • organic solvents used in combination with the chlorinated organic solvent in the present invention are described below. That is, as another preferable organic solvent, a solvent selected from esters, ketones, ethers, alcohols, hydrocarbons and the like having 3 to 12 carbon atoms is preferable.
  • the ester, ketone, ether and alcohol may have a cyclic structure.
  • a compound having two or more functional groups of esters, ketones and ethers can also be used as a solvent, such as an alcoholic hydroxyl group (hydroxyl group). You may have another functional group simultaneously.
  • the number of carbon atoms may be within the specified range of the compound having any functional group.
  • esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.
  • ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, and methylcyclohexanone.
  • ethers having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole.
  • organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.
  • the alcohol used in combination with the chlorinated organic solvent may be linear, branched or cyclic, and among them, saturated aliphatic hydrocarbon is preferable.
  • the hydroxyl group (hydroxyl group) of the alcohol may be any of primary to tertiary.
  • Examples of the alcohol include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, 2-methyl-2-butanol and cyclohexanol.
  • fluorine-based alcohol is also used. Examples thereof include 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol and the like.
  • hydrocarbon may be linear, branched or cyclic. Either aromatic hydrocarbons or aliphatic hydrocarbons can be used.
  • the aliphatic hydrocarbon may be saturated or unsaturated.
  • hydrocarbons examples include cyclohexane, hexane, benzene, toluene and xylene.
  • Examples of combinations of chlorinated organic solvents and other organic solvents include the following compositions, but are not limited thereto.
  • Dichloromethane / methanol / butanol / cyclohexane 80/10/5/5, parts by mass
  • Dichloromethane / methyl ethyl ketone / methanol / butanol 80/10/5/5, parts by mass
  • Dichloromethane / cyclopentanone / methanol / isopropanol 80/7/5/8, part by mass
  • Non-chlorine solvent Next, the non-chlorine organic solvent that is preferably used in preparing the cellulose ester solution according to the present invention will be described.
  • the non-chlorine organic solvent is not particularly limited as long as the object can be achieved within a range in which the cellulose ester can be dissolved and solution casting can be performed.
  • the non-chlorine organic solvent used in the present invention is preferably a solvent selected from esters, ketones and ethers having 3 to 12 carbon atoms.
  • Ester, ketone and ether may have a cyclic structure.
  • a compound having two or more functional groups of esters, ketones and ethers can also be used as a main solvent, for example, an alcoholic hydroxyl group (hydroxyl group) Such other functional groups may be included.
  • the number of carbon atoms may be within the specified range of the compound having any functional group.
  • esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.
  • ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone and methylcyclohexanone.
  • ethers having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole.
  • organic solvent having two or more kinds of functional groups examples include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.
  • the non-chlorine organic solvent used in the above cellulose ester is selected from the various viewpoints described above, and is preferably as follows.
  • the non-chlorine solvent is preferably a mixed solvent containing the non-chlorine organic solvent as a main solvent, and is a mixed solvent of three or more different solvents, wherein the first solvent is methyl acetate, ethyl acetate, At least one selected from methyl formate, ethyl formate, acetone, dioxolane, and dioxane, or a mixture thereof; the second solvent is selected from ketones having 4 to 7 carbon atoms or acetoacetate;
  • the solvent is a mixed solvent selected from alcohols or hydrocarbons having 1 to 10 carbon atoms, more preferably alcohols having 1 to 8 carbon atoms.
  • the second solvent may not be present.
  • the first solvent is more preferably methyl acetate, acetone, methyl formate, ethyl formate, or a mixture thereof
  • the second solvent is preferably methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl acetyl acetate, or a mixed solvent thereof. It may be.
  • the alcohol as the third solvent may be linear, branched or cyclic, and is preferably a saturated aliphatic hydrocarbon.
  • the hydroxyl group (hydroxyl group) of the alcohol may be any of primary to tertiary.
  • examples of the alcohol include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, 2-methyl-2-butanol and cyclohexanol.
  • a fluorinated alcohol is also used.
  • examples thereof include 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol and the like.
  • hydrocarbon may be linear, branched or cyclic. Either aromatic hydrocarbons or aliphatic hydrocarbons can be used.
  • the aliphatic hydrocarbon may be saturated or unsaturated.
  • hydrocarbons include cyclohexane, hexane, benzene, toluene and xylene.
  • These third solvents which are alcohols and hydrocarbons, may be used alone or as a mixture of two or more, and are not particularly limited.
  • preferred specific compounds include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and cyclohexanol, cyclohexane, and hexane as alcohols.
  • the mixing ratio of the above three mixed solvents is that the first solvent is 20 to 95% by mass, the second solvent is 2 to 60% by mass, and the third solvent is 2 to 30% by mass in the total amount of the mixed solvent.
  • the first solvent is 30 to 90% by mass
  • the second solvent is 3 to 50% by mass
  • the third alcohol is preferably 3 to 25% by mass. .
  • the first solvent is 30 to 90% by mass
  • the second solvent is 3 to 30% by mass
  • the third solvent is alcohol and 3 to 15% by mass.
  • the non-chlorine-based organic solvent used in the present invention is more specifically described in JIII Journal of Technical Disclosure No. 2001-1745 (issued March 15, 2001, Invention Association) p. 12-16. Although the preferable combination of the said non-chlorine type
  • the cellulose ester solution prepared by the following method can also be used.
  • dichloromethane is used in an amount of 10% by mass or less of the total organic solvent amount. You may make it contain.
  • the cellulose ester solution used is a solution obtained by dissolving cellulose ester in the organic solvent at a concentration of 10 to 30% by mass. It is preferable in terms of film suitability, more preferably 13 to 27% by mass, and particularly preferably 15 to 25% by mass.
  • the cellulose ester solution having these concentrations may be prepared by dissolving the cellulose ester so as to have a predetermined concentration, or after preparing a low concentration solution (for example, 9 to 14% by mass) in advance, the concentration described later It is good also as a predetermined high concentration solution through a process. Furthermore, after preparing a high concentration cellulose ester solution in advance, a predetermined low concentration cellulose ester solution may be obtained by adding various additives.
  • the cellulose ester film is produced by a solution casting film forming method
  • a diluted solution in which cellulose ester is dissolved at a concentration of 0.1 to 5% by mass in an organic solvent having the same composition as the cellulose ester solution in a diluted solution in which cellulose ester is dissolved at a concentration of 0.1 to 5% by mass in an organic solvent having the same composition as the cellulose ester solution,
  • the molecular weight of the aggregate of the cellulose ester is preferably 150,000 to 15 million from the viewpoint of improving the peelability.
  • the associated molecular weight is 180,000 to 9 million.
  • This associated molecular weight can be determined by a static light scattering method.
  • it is preferable that the inertial radius required simultaneously is dissolved so as to be 10 to 200 nm.
  • a more preferable inertial square radius is 20 to 200 nm. Furthermore, it is preferable to dissolve so that the second virial coefficient is ⁇ 2 ⁇ 10 ⁇ 4 to + 4 ⁇ 10 ⁇ 4, and more preferably, the second virial coefficient is ⁇ 2 ⁇ 10 ⁇ 4 to + 2 ⁇ 10 ⁇ 4. It is.
  • association molecular weight the inertial square radius, and the definition of the second virial coefficient. These are measured using the static light scattering method according to the following method.
  • the measurement is performed in a dilute region for the convenience of the apparatus, but these measured values reflect the behavior of the dope in the high concentration region.
  • the cellulose ester is dissolved in a solvent used for the dope to prepare 0.1% by mass, 0.2% by mass, 0.3% by mass, and 0.4% by mass solution.
  • the cellulose ester is dried at 120 ° C. for 2 hours and is measured at 25 ° C. and 10% RH.
  • the dissolution method is carried out according to the method employed at the time of dope dissolution (room temperature dissolution method, cooling dissolution method, high temperature dissolution method).
  • the refractive index necessary for this analysis is the value of the solvent obtained by the Abbe refracting system, and the refractive index concentration gradient (dn / dc) is determined using a differential refractometer (DRM-1021 manufactured by Otsuka Electronics Co., Ltd.). Measure using the solvent and solution used for light scattering measurement.
  • the method for dissolving the cellulose ester is not particularly limited, and may be room temperature, and further, a cooling dissolution method or a high temperature dissolution method, and further a combination thereof.
  • the cellulose ester dope solution according to the present invention is usually subjected to solution concentration and filtration.
  • the Japan Institute of Invention and Innovation Technical Bulletin No. 2001-1745 (issued March 15, 2001, Invention Association) p. 25 in detail.
  • the cellulose ester solution preferably has a viscosity and a dynamic storage elastic modulus within the ranges described below because it is easy to cast. 1 ml of the sample solution is measured on a rheometer (CLS 500) using a Steel Cone (both manufactured by TA Instruments) having a diameter of 4 cm / 2 °.
  • Measurement conditions were measured by varying the range from 40 ° C. to ⁇ 10 ° C. at 2 ° C./min with Oscillation Step / Temperature Ramp, static non-Newtonian viscosity n * (Pa ⁇ s) at 40 ° C. and storage at 5 ° C.
  • the elastic modulus G ′ (Pa) is obtained.
  • the sample solution is kept at the measurement start temperature until the liquid temperature becomes constant, and then the measurement is started.
  • the viscosity at 40 ° C. is 1 to 400 Pa ⁇ s
  • the dynamic storage elastic modulus at 15 ° C. is preferably 500 Pa or more, and more preferably the viscosity at 40 ° C. is 10 to 200 Pa ⁇ s.
  • the dynamic storage modulus at 15 ° C. is 1 to 1 million.
  • the dynamic storage elastic modulus at low temperature is large.
  • the dynamic storage elastic modulus at ⁇ 50 ° C. is preferably 10,000 to 1,000,000 Pa at ⁇ 5 ° C.
  • the dynamic storage elastic modulus at ⁇ 50 ° C. is preferably 10,000 to 5 million Pa.
  • the above-mentioned specific cellulose ester since the above-mentioned specific cellulose ester is used, it is characterized in that a high concentration dope is obtained, and a cellulose ester solution having a high concentration and excellent stability can be obtained without relying on a means of concentration. can get.
  • the concentration method is not particularly limited.
  • the low-concentration solution is guided between the cylindrical body and the rotation trajectory of the outer periphery of the rotating blade rotating in the circumferential direction, and the temperature between the solution and the solution.
  • a method for obtaining a high-concentration solution while evaporating the solvent by giving a difference for example, Japanese Patent Laid-Open No. 4-259511
  • blowing a heated low-concentration solution into the container from the nozzle blowing a heated low-concentration solution into the container from the nozzle, and until the solution hits the inner wall of the container from the nozzle
  • the solvent is flash evaporated and the solvent vapor is withdrawn from the container and the concentrated solution is withdrawn from the bottom of the container (eg, US Pat. No. 2,541,012, US Pat. No. 2,858,229, US Pat. No. 4,414,341, US Pat. No. 4,504,355, etc.).
  • a suitable filter medium such as a wire mesh or flannel.
  • a filter having an absolute filtration accuracy of 0.1 to 100 ⁇ m it is preferable to use a filter having an absolute filtration accuracy of 0.5 to 25 ⁇ m.
  • the thickness of the filter is preferably 0.1 to 10 mm, more preferably 0.2 to 2 mm.
  • the filtration pressure is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, further 1.0 MPa or less, and particularly preferably 0.2 MPa or less.
  • the filter medium conventionally known materials such as glass fibers, cellulose fibers, filter paper, fluororesins such as tetrafluoroethylene resin can be preferably used, and ceramics, metals and the like are particularly preferably used.
  • the viscosity of the cellulose ester solution immediately before film formation may be in a range that allows casting, and is usually adjusted to a range of 10 Pa ⁇ s to 2000 Pa ⁇ s, preferably 30 Pa ⁇ s to 1000 Pa ⁇ s. s is more preferable, and 40 Pa ⁇ s to 500 Pa ⁇ s is more preferable.
  • the temperature at this time is not particularly limited as long as it is a temperature at the time of casting, but is preferably ⁇ 5 to + 70 ° C., more preferably ⁇ 5 to + 55 ° C.
  • the cellulose ester film according to the present invention can be obtained by forming a film using the cellulose ester solution.
  • a solution casting film forming apparatus conventionally used for producing a cellulose triacetate film is used.
  • the dope (cellulose ester solution) prepared from the dissolving machine (kettle) is temporarily stored in a storage kettle, and the foam contained in the dope is defoamed for final preparation.
  • the dope is sent from the dope discharge port to the pressure die through a pressure metering gear pump capable of delivering a constant amount of liquid with high accuracy, for example, by the number of rotations, and the dope is run endlessly from the die (slit) of the pressure die.
  • the dry-dried dope film (also referred to as web) is peeled off from the metal support at a peeling point that is uniformly cast on the metal support and substantially rounds the metal support.
  • the both ends of the obtained web are sandwiched between clips, transported by a tenter while holding the width, dried, then transported by a roll group of a drying device, dried, and wound up to a predetermined length by a winder.
  • the combination of a tenter and a roll group dryer varies depending on the purpose.
  • a coating device is often added. Although each manufacturing process is described briefly below, it is not limited to these.
  • the prepared cellulose ester solution (dope) is formed by casting the dope on a drum or a band and evaporating the solvent when producing a cellulose ester film by a solution casting film forming method.
  • the concentration of the dope before casting is preferably adjusted so that the solid content is 5 to 40% by mass.
  • the surface of the drum or band is preferably finished in a mirror state.
  • the dope is preferably cast on a drum or band having a surface temperature of 30 ° C. or less, and particularly preferably a metal support temperature of ⁇ 10 to 20 ° C.
  • the methods described in JP-A Nos. 55-014201, 02-111511, and 02-208650 can be used in the present invention.
  • the cellulose ester solution may be cast as a single layer liquid on a smooth band or drum as a metal support, or a plurality of cellulose ester liquids of two or more layers may be cast.
  • a film When casting a plurality of cellulose ester solutions, even if a film is produced while casting and laminating a solution containing a cellulose ester from a plurality of casting openings provided at intervals in the traveling direction of the metal support, for example, the methods described in JP-A-61-158414, JP-A-1-122419, and JP-A-11-198285 can be applied.
  • a film may be formed by casting a cellulose ester solution from two casting ports.
  • JP-B-60-27562, JP-A-61-94724, JP-A-61-947245, JP-A-6-947245 It can be carried out by the methods described in JP-A-61-104813, JP-A-61-158413, and JP-A-6-134933.
  • a cellulose ester film casting method described in Japanese Patent Application Laid-Open No. 56-162617 is a method of wrapping a flow of a high viscosity cellulose ester solution with a low viscosity cellulose ester solution and simultaneously extruding the high and low viscosity cellulose ester solution. Good. Furthermore, it is also a preferable embodiment that the outer solution described in JP-A-61-94724 and JP-A-61-94725 contains a larger amount of an alcohol component which is a poor solvent than the inner solution.
  • the film cast on the metal support is peeled off by the first casting port, and the second casting is performed on the side in contact with the metal support surface.
  • a film may be produced, for example, a method described in Japanese Patent Publication No. 44-20235.
  • the cellulose ester solution to be cast may be the same solution or different cellulose ester solutions, and is not particularly limited. In order to give a function to a plurality of cellulose ester layers, a cellulose ester solution corresponding to the function may be extruded from each casting port.
  • the cellulose ester solution may be cast simultaneously with other functional layers (for example, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer, a UV absorption layer, and a polarizer).
  • functional layers for example, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer, a UV absorption layer, and a polarizer.
  • the inner and outer thicknesses are not particularly limited, but the outer side is preferably 1 to 50% of the total film thickness, more preferably 2 to 30%.
  • a cellulose ester film having a laminated structure can be produced by co-casting cellulose ester solutions having different additive concentrations such as the above-mentioned plasticizer, ultraviolet absorber and matting agent.
  • a cellulose ester film having a structure of skin layer / core layer / skin layer can be produced.
  • the matting agent can be contained in the skin layer in a large amount or only in the skin layer.
  • the plasticizer and the UV absorber can be contained in the core layer more than the skin layer, and may be contained only in the core layer.
  • the type of plasticizer and ultraviolet absorber can be changed between the core layer and the skin layer.
  • at least one of a low-volatile plasticizer and an ultraviolet absorber is included in the skin layer, and the core layer is made plastic. It is also possible to add an excellent plasticizer or an ultraviolet absorber excellent in ultraviolet absorption.
  • a peeling accelerator is contained only in the skin layer on the metal support side. It is also preferable to add more alcohol, which is a poor solvent, to the skin layer than the core layer in order to cool the metal support by the cooling drum method to gel the solution.
  • the Tg of the skin layer and the core layer may be different, and the Tg of the core layer is preferably lower than the Tg of the skin layer.
  • the viscosity of the solution containing the cellulose ester at the time of casting may be different between the skin layer and the core layer, and the viscosity of the skin layer is preferably smaller than the viscosity of the core layer. It may be smaller than the viscosity.
  • the endlessly running metal support used to manufacture the cellulose ester film according to the present invention includes a drum whose surface is mirror-finished by chrome plating and a stainless steel belt (which is called a band) whose surface is mirror-finished by surface polishing. May be used).
  • the pressure die used for the production of the cellulose ester film according to the present invention may be one or two or more installed above the metal support.
  • the amount of dope to be cast may be divided into various ratios for each die, or the dope may be fed to the dies from each of a plurality of precision quantitative gear pumps.
  • the temperature of the cellulose ester solution used for casting is preferably ⁇ 10 to 55 ° C., more preferably 25 to 50 ° C. In that case, all of the steps may be the same or may be different at different points in the step. If they are different, the temperature may be a desired temperature just before casting.
  • the dope drying on the metal support involved in the production of the cellulose ester film is generally performed by applying hot air from the surface side of the metal support (drum or belt), that is, the surface of the web on the metal support, drum Alternatively, a method in which hot air is applied from the back of the belt, a liquid whose temperature is controlled is brought into contact with the back of the belt or drum opposite the dope casting surface, and the drum or belt is heated by heat transfer to control the surface temperature. Although there is a heat method, the back surface liquid heat transfer method is preferable.
  • the surface temperature of the metal support before casting may be any number as long as it is not higher than the boiling point of the solvent used for the dope.
  • the temperature is set to 1 to 10 ° C. lower than the boiling point of the lowest boiling solvent among the solvents used. It is preferable. This is not the case when the casting dope is cooled and peeled off without drying.
  • the retardation of the cellulose ester film according to the present invention can be adjusted by a stretching treatment.
  • JP-A-62-115035 JP-A-4-152125, JP-A-4-284221, JP-A-4-298310, and JP-A-11-298310. -48271 and the like.
  • the film is stretched at room temperature or under heating conditions.
  • the heating temperature is preferably not higher than the glass transition temperature of the film.
  • the stretching of the film may be uniaxial stretching only in the longitudinal or lateral direction, or may be simultaneous or sequential biaxial stretching. Stretching is performed at 1 to 200%.
  • the stretching is preferably 1 to 100%, particularly preferably 1 to 50%.
  • the birefringence of the optical film is preferably such that the refractive index in the width direction is larger than the refractive index in the length direction. Therefore, it is preferable to stretch more in the width direction.
  • the stretching process may be performed in the middle of the film forming process, or the raw film that has been formed and wound may be stretched.
  • the stretching may be performed in a state including the residual solvent amount, and the stretching can be preferably performed with the residual solvent amount of 2 to 30%.
  • the film thickness of the cellulose ester film according to the present invention obtained after drying varies depending on the purpose of use, but is preferably 20 to 50 ⁇ m in order to obtain the effects of the present invention.
  • the thickness of the film may be adjusted by adjusting the solid content concentration contained in the dope, the slit gap of the die base, the extrusion pressure from the die, the metal support speed, and the like.
  • the width of the cellulose ester film obtained as described above is preferably 0.5 to 3 m, more preferably 0.6 to 2.5 m, and still more preferably 0.8 to 2.2 m.
  • the length is preferably 100 to 10,000 m per roll, more preferably 500 to 7000 m, and still more preferably 1000 to 6000 m.
  • the width is preferably 3 mm to 50 mm, more preferably 5 mm to 30 mm, and the height is preferably 0.5 to 500 ⁇ m, more preferably 1 to 200 ⁇ m. This may be a single push or a double push.
  • the variation of the Ro (590) value of the full width is preferably ⁇ 5 nm, more preferably ⁇ 3 nm. Further, the variation of the Rt (590) value is preferably ⁇ 10 nm, and more preferably ⁇ 5 nm. Moreover, it is preferable that the variation in the Ro value and the Rt value in the length direction is also within the range of the variation in the width direction.
  • the cellulose ester film used for the second optically anisotropic layer is combined with the first optically anisotropic layer having predetermined optical characteristics to widen the viewing angle of a liquid crystal display device, particularly an IPS mode liquid crystal display device. In order to contribute to this, it is necessary to satisfy the following relational expressions (I) to (III).
  • Ro (1) (nx ⁇ ny) ⁇ d
  • Ro (2) (nx + ny) / 2 ⁇ nz) ⁇ d
  • Ro (2) (nx ⁇ ny) ⁇ d
  • Rt (2) ((nx + ny) / 2 ⁇ nz) ⁇ d
  • Nz Rt / Ro + 0.5
  • Nz is preferably adjusted to 1.5 to 7.0. 2.0 to 5.5 is more preferably adjusted. Particularly preferred is 2.5 to 4.5.
  • Ro ( ⁇ nm) and Rt ( ⁇ nm) respectively represent in-plane retardation and retardation in the thickness direction at the measurement wavelength ⁇ nm.
  • Ro ( ⁇ nm) is measured by making light of wavelength ⁇ nm incident in the normal direction of the film in KOBRA-21ADH (manufactured by Oji Scientific Instruments).
  • Rt ( ⁇ ) is the wavelength of ⁇ nm from the direction inclined by + 40 ° with respect to the normal direction of the film, with the in-plane slow axis (determined by KOBRA-21ADH) as the tilt axis (rotary axis).
  • Retardation value measured by making light incident, and measuring by making light of wavelength ⁇ nm incident from a direction inclined by ⁇ 40 ° with respect to the normal direction of the film with the in-plane slow axis as the tilt axis (rotation axis) KOBRA 21ADH calculates based on the retardation values measured in a total of three directions.
  • the average refractive index of the cellulose ester at the wavelength is measured using an Abbe refractometer and a spectral light source, and nx, ny, and nz are calculated by KOBRA 21ADH by inputting the measured value of the average refractive index and the film thickness.
  • the measurement wavelength is set to 590 nm unless specifically described for Ro and Rt.
  • the variation of the slow axis angle in the film plane of the cellulose ester film according to the present invention is preferably in the range of -2 to +2 degrees with respect to the reference direction of the roll film, and in the range of -1 to +1 degrees. Is more preferable, and most preferably in the range of ⁇ 0.5 ° to + 0.5 °.
  • the reference direction is the longitudinal direction of the roll film when the cellulose ester film is longitudinally stretched, and the width direction of the roll film when laterally stretched.
  • the difference ⁇ Rt ( Rt (10% RH) ⁇ Rt (80% RH)) between the Rt value at 25 ° C. and 80% RH at 0 ° C. is 0 to 30 nm. It is preferable in reducing the color change due to.
  • the cellulose ester film according to the present invention preferably has an equilibrium water content of not more than 3.2% at 25 ° C. and 80% RH in order to reduce the color change with time of the liquid crystal display device.
  • the moisture content is measured by measuring a cellulose ester film sample 7 mm ⁇ 35 mm according to the present invention by a Karl Fischer method using a moisture measuring device and a sample drying apparatus (CA-03, VA-05, both Mitsubishi Chemical Corporation). . It is calculated by dividing the amount of water (g) by the sample mass (g).
  • the cellulose ester film used for the second optically anisotropic layer according to the present invention has a moisture permeability at 60 ° C. and 95% RH of 600 g / m 2 ⁇ 24 hr to 1500 g / m 2 ⁇ 24 hr. This is necessary to reduce the color change of the liquid crystal display device over time.
  • the cellulose ester film according to the present invention preferably has a haze of 0.01 to 2%.
  • the haze can be measured as follows.
  • the haze is measured by measuring a 40 mm ⁇ 80 mm cellulose ester film sample according to the present invention at 25 ° C. and 60% RH with a haze meter (NDH2000 type, manufactured by Nippon Denshoku Industries Co., Ltd.) according to JIS K-6714.
  • the cellulose ester film according to the present invention preferably has a mass change of 0 to 5% when left for 48 hours under conditions of 80 ° C. and 90% RH.
  • the cellulose ester film according to the present invention has a dimensional change when allowed to stand for 24 hours under conditions of 60 ° C. and 95% RH, and a dimension when allowed to stand for 24 hours under conditions of 90 ° C. and 5% RH.
  • the degree of change is preferably 0 to 5%.
  • the photoelastic coefficient is 50 ⁇ 10 ⁇ 13 cm 2 / dyne or less in order to reduce the color change with time of the liquid crystal display device.
  • the first optically anisotropic layer according to the present invention is a film composed of a resin exhibiting negative birefringence and having an in-plane retardation Ro (1) in the range of ⁇ 40 to 20 nm.
  • the retardation Rt (1) in the thickness direction is in the range of ⁇ 400 to ⁇ 80 nm.
  • the variation of the slow axis angle in the film plane of the first optically anisotropic layer according to the present invention is preferably in the range of ⁇ 2 degrees to +2 degrees with respect to the reference direction when the film is a roll film, More preferably, it is in the range of 1 degree to +1 degree, and most preferably in the range of -0.5 degree to +0.5 degree.
  • the reference direction is the longitudinal direction of the roll film of the first optical anisotropic layer or the width direction of the roll film of the first optical anisotropic layer.
  • the moisture permeability of the film constituting the first optically anisotropic layer at 60 ° C., 95% RH, and 24 hr is 20 to 600 g from the viewpoint of preventing birefringence unevenness, polarizer deterioration, image display deterioration, and the like. / M 2 ⁇ 24h.
  • the first optically anisotropic layer using an acrylic resin-containing film that satisfies the following requirements.
  • the acrylic resin-containing film according to the present invention has a haze value of less than 1%, a tension softening point of 105 to 145 ° C., no ductile fracture, and an in-plane retardation Ro (1) of ⁇ 40 to 20 nm.
  • the retardation Rt (1) in the thickness direction is in the range of ⁇ 400 to ⁇ 80 nm.
  • These retardations Ro (1) and Rt (1) are preferably controlled in a stretching process when a film is produced.
  • the optically anisotropic layer according to the present invention uses a resin that develops negative birefringence by stretching, it is possible to set Ro (1) to a non-zero value by using a stretched film. Are better.
  • fine adjustment is possible by stretching the film, and if the Ro is not zero, the color of the liquid crystal display device may be improved. This is because the Ro (2) of the second optically anisotropic layer is not zero, and therefore the first optically anisotropic layer is disposed in Configuration 1 (see FIG. 2) or Configuration 2 (see FIG. 3) of the present invention.
  • Ro (1) is not zero and wavelength dispersibility is different, so that Ro (1) of the first optical anisotropic layer and Ro (2) of the second optical anisotropic layer are combined. It is excellent in that the wavelength dispersion can be controlled.
  • the optical compensation film in which the first optically anisotropic layer has an alignment fixed by a normal method using a liquid crystal having a vertical alignment with respect to the support is designed to have an in-plane retardation of Ro of zero. It is obvious that the viewpoint and the design that combines the in-plane retardation of the first optical anisotropic layer and the second optical anisotropic layer obtained by stretching are different in principle.
  • the in-plane retardation Ro of the acrylic resin-containing film according to the present invention is obtained by, for example, measuring the average refractive index of the resin with an Abbe refractometer-4T using a light source of 590 nm in an environment of 23 ° C. and 55% RH.
  • KOBRA-21ADH Oji Scientific Instruments Co., Ltd.
  • the ductile fracture is caused by a stress that is greater than the strength of a certain material, and is defined as a fracture accompanied by significant elongation or squeezing of the material before the final fracture.
  • the fracture surface is characterized by numerous indentations called dimples.
  • an acrylic resin-containing film that does not cause ductile fracture means that, at 23 ° C. and 55% RH, even when a large stress that bends the film in two is applied, no fracture or the like is observed. Means that the film does not break even when folded.
  • An acrylic resin-containing film in which ductile fracture does not occur can be obtained by selecting the material configuration of the acrylic resin, cellulose ester, and other additives used as described below.
  • the acrylic resin-containing film according to the present invention has a low haze, a high temperature device such as a projector, and a use in a high temperature environment such as an in-vehicle display device.
  • the temperature is preferably 105 ° C to 145 ° C, and more preferably controlled to 110 ° C to 130 ° C.
  • the tension softening point temperature of the acrylic resin-containing film As a specific method for measuring the tension softening point temperature of the acrylic resin-containing film, a tensilon tester (ORIENTEC Co., Ltd., RTC-1225A) was used, and the acrylic resin-containing film was 120 mm (length) ⁇ 10 mm (width). The temperature is increased at a rate of temperature increase of 30 ° C./min while pulling at a tension of 10 N, and the temperature at the time of 9 N is measured three times, and the average value can be obtained.
  • a tensilon tester (ORIENTEC Co., Ltd., RTC-1225A) was used, and the acrylic resin-containing film was 120 mm (length) ⁇ 10 mm (width).
  • the temperature is increased at a rate of temperature increase of 30 ° C./min while pulling at a tension of 10 N, and the temperature at the time of 9 N is measured three times, and the average value can be obtained.
  • the acrylic resin-containing film according to the present invention preferably has a glass transition temperature (Tg) of 110 ° C. or higher. More preferably, it is 120 ° C. or higher. Especially preferably, it is 150 degreeC or more.
  • Tg glass transition temperature
  • the glass transition temperature here is measured at a heating rate of 20 ° C./min using a differential scanning calorimeter (DSC-7, manufactured by Perkin Elmer Co., Ltd.), and determined according to JIS K7121 (1987).
  • the intermediate glass transition temperature (Tmg) is measured at a heating rate of 20 ° C./min using a differential scanning calorimeter (DSC-7, manufactured by Perkin Elmer Co., Ltd.), and determined according to JIS K7121 (1987).
  • the intermediate glass transition temperature (Tmg) The intermediate glass transition temperature (Tmg).
  • the acrylic resin-containing film according to the present invention has a defect of 5 ⁇ m or more in diameter in the film plane of 1 piece / 10 cm square or less. More preferably, it is 0.5 piece / 10 cm square or less, more preferably 0.1 piece / 10 cm square or less.
  • the diameter of the defect indicates the diameter when the defect is circular, and when it is not circular, the range of the defect is determined by observing with a microscope according to the following method, and the maximum diameter (diameter of circumscribed circle) is determined.
  • the range of the defect is the size of the shadow when the defect is observed with the transmitted light of the differential interference microscope when the defect is a bubble or a foreign object.
  • the defect is a change in the surface shape, such as transfer of a roll flaw or an abrasion
  • the size is confirmed by observing the defect with the reflected light of a differential interference microscope.
  • the film breaks with the defect as a starting point, and the productivity may be significantly reduced.
  • the diameter of a defect becomes 5 micrometers or more, it can confirm visually by polarizing plate observation etc., and when used as an optical member, a bright spot may arise.
  • the coating agent may not be formed uniformly, resulting in defects (coating defects).
  • the defect is a void in the film (foaming defect) generated due to the rapid evaporation of the solvent in the drying process of the solution casting, a foreign matter in the film forming stock solution, or a foreign matter mixed in the film forming. This refers to the foreign matter (foreign matter defect) in the film.
  • the acrylic resin-containing film according to the present invention is produced by producing a raw film of a film by a solution casting film forming method or a melt extrusion film forming method, and performing a stretching operation by softening the dried film by heating. By carrying out a stretching operation in a state in which the solvent remains by the film-forming method and then drying to obtain a film, an optically negative retardation can be expressed with respect to stretching.
  • the diameter of the defect may be increased by a stretching operation for developing retardation.
  • the defects in the above-mentioned film are 1/10 cm square or less of defects having a diameter of 5 ⁇ m or more in the film plane as the diameter and number after the stretching operation for developing retardation. More preferably, it is 0.5 piece / 10 cm square or less, more preferably 0.1 piece / 10 cm square or less.
  • the acrylic resin-containing film according to the present invention preferably has a breaking elongation in at least one direction of 10% or more, more preferably 20% or more, as measured in accordance with JIS-K7127-1999.
  • the upper limit of the elongation at break is not particularly limited, but is practically about 250%. In order to increase the elongation at break, it is effective to suppress defects in the film caused by foreign matter and foaming.
  • the film thickness of the acrylic resin-containing film according to the present invention is not particularly limited, but is preferably 20 to 200 ⁇ m when used for a polarizing plate protective film described later. From the viewpoints of properties, foaming, solvent drying, etc., it is more preferably 25 to 100 ⁇ m, particularly preferably 30 to 80 ⁇ m.
  • the acrylic resin-containing film according to the present invention preferably has a total light transmittance of 90% or more, more preferably 93% or more. Moreover, as a realistic upper limit, it is about 99%. In order to achieve excellent transparency expressed by such total light transmittance, it is necessary not to introduce additives and copolymerization components that absorb visible light, or to remove foreign substances in the polymer by high-precision filtration. It is effective to reduce the diffusion and absorption of light inside the film.
  • the acrylic resin-containing film according to the present invention is characterized in that the haze value (turbidity), which is one of the indices indicating transparency, is 1.0% or less, but the luminance when incorporated in a liquid crystal display device From the viewpoint of contrast, it is preferably 0.5% or less.
  • the surface roughness also affects the haze value as surface haze, it is also effective to suppress the particle diameter and addition amount of acrylic particles within the above range, or to reduce the surface roughness of the film contact portion during film formation It is.
  • the total light transmittance and haze value of the acrylic resin-containing film are values measured according to JIS-K7361-1-1997 and JIS-K7136-2000.
  • the acrylic resin-containing film according to the present invention can be preferably used as an acrylic resin-containing film for optical use as long as it satisfies the physical properties as described above. An excellent film can be obtained.
  • the acrylic resin-containing film contains an acrylic resin and a cellulose ester resin in a mass ratio of 95: 5 to 30:70, and the total acyl groups of the cellulose ester resin.
  • the degree of substitution (T) is 2.00 to 3.00
  • the degree of substitution of acetyl group (ac) is 0 to 1.89
  • the number of carbons of acyl groups other than acetyl groups is 3 to 7
  • the excellent effect of the present invention can be obtained by an acrylic resin-containing film characterized by having an A of 75,000 to 280000.
  • the acrylic resin and the cellulose ester resin are contained in a mass ratio of 95: 5 to 30:70, but the acrylic resin is preferably 50% by mass or more.
  • the acrylic resin component When the acrylic resin component is increased, for example, the dimensional change under high temperature and high humidity is suppressed, and curling of the polarizing plate and warping of the panel when used as a polarizing plate can be remarkably reduced.
  • the above physical properties can be maintained for a longer time.
  • the total mass of the acrylic resin and the cellulose ester resin is 55 to 100% by mass, preferably 60 to 99% by mass of the acrylic resin-containing film.
  • the acrylic resin used in the present invention includes a methacrylic resin.
  • the acrylic resin is characterized by having an intrinsic birefringence of ⁇ 0.005 or less.
  • the intrinsic birefringence of the acrylic resin being ⁇ 0.005 or less means that the intrinsic birefringence of the entire acrylic resin is ⁇ 0.005 or less when the acrylic resin is made of one or more acrylic resins. Say. Preferably it is -0.01 or less.
  • the acrylic film according to the present invention is characterized in that it has the functions of a polarizing plate protective film and a retardation film.
  • homopolymers In order to set the intrinsic birefringence of the acrylic resin to -0.005 or less, for example, among acrylic monomers, styrene monomers, maleimide monomers and other derivatives, homopolymers have negative intrinsic birefringence. Monomers are copolymerized or a resin having a large negative intrinsic birefringence is mixed. A homopolymer is preferably a resin obtained by copolymerizing a resin monomer having a negative intrinsic birefringence.
  • a homopolymer that exhibits positive intrinsic birefringence may be used as a monomer for copolymerization or blended to control the wavelength dispersion of birefringence.
  • the acrylic resin according to the present invention is preferably composed of 50 to 99% by mass of an acrylic monomer and 1 to 50% by mass of another monomer copolymerizable therewith.
  • acrylic monomer that forms the acrylic resin according to the present invention examples include alkyl methacrylates having 1 to 18 carbon atoms in the alkyl number and alkyl acrylates having 1 to 18 carbon atoms in the alkyl number.
  • Styrene monomers preferable as the copolymerization monomer for the acrylic resin according to the present invention include, for example, styrene, ⁇ -methylstyrene, o-methylstyrene, p-methylstyrene, p-chlorostyrene, p-nitrostyrene, and p-amino. Examples thereof include styrene, p-carboxyl styrene, p-phenyl styrene, 2,5-dichlorostyrene, pt-butyl styrene and the like.
  • preferable maleimide monomers include, for example, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N-phenylmaleimide, N- (2 -Methylphenyl) maleimide, N- (2-ethylphenyl) maleimide, N- (2-n-propylphenyl) maleimide, N- (2-isopropylphenyl) maleimide, N- (2,6-dimethylphenyl) maleimide, N- (2,6-diethylphenyl) maleimide, N- (2,6-di-isopropylphenyl) maleimide, N- (2-methyl-6-ethylphenyl) maleimide, N- (2-chlorophenyl) maleimide, N -(2,6-dibromophenyl) maleimide, N -(2,6-dibromophenyl) male
  • the maleimide monomer can be obtained from, for example, Tokyo Chemical Industry Co., Ltd.
  • the acrylic resin can be copolymerized with other monomers.
  • examples of other monomers include ethylene, propylene, 1-butene, isobutene, 1,3-butadiene, 2-methyl-1-butene, 2-methyl-1-pentene, 2-methyl-2-pentene, 1- Examples include hexene, acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, maleic anhydride, and vinyl acetate.
  • the acrylic resin according to the present invention contains a monomer other than the styrene monomer and the maleimide monomer
  • the content of the other monomer is 1% by mass or more and 90% by mass or less of the components other than the acrylic monomer. It is preferably 5 to 40% by mass, particularly preferably 10 to 30% by mass.
  • the acrylic resin according to the present invention is methyl methacrylate / styrene copolymer, methyl methacrylate / styrene / maleic anhydride copolymer, methyl methacrylate / styrene / (meth) acrylonitrile copolymer, styrene / methyl acrylate copolymer.
  • orientation birefringence and intrinsic birefringence of a polymer are expressed by the following relational expression.
  • ⁇ n f ⁇ n0
  • ⁇ n orientation birefringence
  • f an orientation function
  • ⁇ n0 intrinsic birefringence of the polymer
  • the measurement of intrinsic birefringence is obtained experimentally by measuring the orientation birefringence and the orientation function, and the intrinsic birefringence of the acrylic resin-containing film material according to the present invention is obtained using this relational expression.
  • the material whose refractive index decreases with respect to the stretching direction is defined as a material having negative birefringence, and the sign of intrinsic birefringence is negative.
  • the acrylic resin-containing film according to the present invention is characterized in that the intrinsic birefringence is negative.
  • stretching in the width direction and stretching in the film forming direction are performed simultaneously, or by combining the stretching steps sequentially to smooth the surface of the film, and at the same time, the retardation of the film is the target range. Can be controlled.
  • the acrylic resin used in the acrylic resin-containing film according to the present invention preferably has a weight average molecular weight (Mw) of 80000 to 1000000.
  • the weight average molecular weight of the acrylic resin according to the present invention can be measured by gel permeation chromatography (GPC method).
  • the measurement conditions are as follows.
  • the production method of the acrylic resin in the present invention is not particularly limited, and any known method such as suspension polymerization, emulsion polymerization, bulk polymerization, or solution polymerization may be used.
  • the polymerization initiator a normal peroxide type or azo type can be used, and a redox type can also be used.
  • the polymerization temperature may be 30 to 100 ° C. for suspension or emulsion polymerization, and 80 to 160 ° C. for bulk or solution polymerization.
  • polymerization can be carried out using alkyl mercaptan or the like as a chain transfer agent.
  • the acrylic resin By making the acrylic resin have the above molecular weight, both heat resistance and brittleness can be achieved.
  • ⁇ Cellulose ester resin used for the first optically anisotropic layer> In the material which comprises the acrylic resin containing film which concerns on this invention, when blending cellulose ester resin with an acrylic resin, it can use for the purpose of improving heat resistance seeing from an acrylic resin, and improving brittleness.
  • the cellulose resin may be substituted with either an aliphatic acyl group or an aromatic acyl group, but is preferably substituted with at least an acetyl group from the viewpoint of increasing heat resistance. From the viewpoint of application to an optical film, transparency suitable for an image display device can be obtained by compatibility of both an acrylic resin and a cellulose ester resin more than a simple blend.
  • the cellulose ester resin can be dissolved to give an appropriate moisture permeability to the film.
  • the cellulose ester resin functions as a moisture permeability improver and is used in the polarizing plate of the present invention.
  • a film as the first optically anisotropic layer to be used can be obtained.
  • the aliphatic acyl group has 2 to 20 carbon atoms, specifically acetyl, propionyl, butyryl, isobutyryl, valeryl, pivaloyl, hexanoyl , Octanoyl, lauroyl, stearoyl and the like.
  • the use of a mixed ester having an acetyl group and another aliphatic acyl group is preferable from the viewpoint of compatibility for modification of the acrylic resin, and it is particularly preferable to use cellulose acetate propionate or cellulose acetate butyrate.
  • the aliphatic acyl group is meant to include those further having a substituent.
  • the aromatic ring is a benzene ring in the above-described aromatic acyl group
  • the substituent of the benzene ring are exemplified.
  • the number of substituents substituted on the aromatic ring is 0 or 1 to 5, preferably 1 to 3, particularly preferably 1 Or two.
  • introduction of an aromatic ring into the cellulose ester resin can be preferably selected from the viewpoint of developing negative birefringence.
  • substituents substituted on the aromatic ring when the number of substituents substituted on the aromatic ring is 2 or more, they may be the same or different from each other, but they may be linked together to form a condensed polycyclic compound (for example, naphthalene, indene, indane, phenanthrene, quinoline). , Isoquinoline, chromene, chroman, phthalazine, acridine, indole, indoline, etc.).
  • a condensed polycyclic compound for example, naphthalene, indene, indane, phenanthrene, quinoline.
  • Isoquinoline chromene, chroman, phthalazine, acridine, indole, indoline, etc.
  • the cellulose ester resin has a structure selected from at least one of a substituted or unsubstituted aliphatic acyl group and a substituted or unsubstituted aromatic acyl group, and is used as a structure used in the cellulose resin according to the present invention. These may be cellulose alone or mixed acid esters.
  • the substitution degree of the cellulose ester resin according to the present invention is such that the total substitution degree (T) of the acyl group is 2.00 to 3.00, the acetyl group is not necessarily required, and the substitution degree of acetyl group (ac) is 0 to 1.89. More preferably, the acyl group substitution degree (r) other than the acetyl group is 2.00 to 2.89.
  • the acyl group other than the acetyl group preferably has 3 to 7 carbon atoms.
  • cellulose ester resin those having an acyl group having 2 to 7 carbon atoms as a substituent, that is, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, cellulose It is preferably at least one selected from acetate benzoate and cellulose benzoate.
  • particularly preferable cellulose ester resins include cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.
  • the mixed fatty acid is a lower fatty acid ester of cellulose acetate propionate or cellulose acetate butyrate having an acyl group having 2 to 4 carbon atoms as a substituent.
  • the portion not substituted with an acyl group is usually present as a hydroxyl group (hydroxyl group). These can be synthesized by known methods.
  • substitution degree of the acetyl group and the substitution degree of other acyl groups were determined by the method prescribed in ASTM-D817-96.
  • the object according to the present invention can be achieved even if the weight average molecular weight (Mw) is about 1,000,000. Those having 280000 are preferred, and those having 100,000 to 240,000 are more preferred. This weight average molecular weight can be measured by the GPC method described above.
  • the acrylic resin-containing film may contain acrylic particles.
  • the acrylic particles according to the present invention are characterized by being present in the state of particles in the acrylic resin, cellulose ester resin and acrylic resin-containing film (also referred to as incompatible state).
  • the acrylic particles are obtained by, for example, collecting a predetermined amount of the prepared acrylic resin-containing film, dissolving in a solvent, stirring, and sufficiently dissolving and dispersing the PTFE film having a pore diameter less than the average particle diameter of the acrylic particles. It is preferable that the weight of the insoluble matter filtered and collected using the membrane filter is 90% by mass or more of the acrylic particles added to the acrylic resin-containing film.
  • the acrylic particles used in the present invention are not particularly limited, but are preferably acrylic particles having a layer structure of two or more layers, and particularly preferably the following multilayer structure acrylic granular composite.
  • the multilayer structure acrylic granular composite is formed by laminating the innermost hard layer polymer, the cross-linked soft layer polymer exhibiting rubber elasticity, and the outermost hard layer polymer from the central portion toward the outer peripheral portion.
  • Preferred embodiments of the multilayer structure acrylic granular composite used in the acrylic resin composition according to the present invention include the following.
  • a hard layer polymer (c) comprising 20 to 50% by mass, having an insoluble part when fractionated with acetone, and an acrylic granular composite having a methyl ethyl ketone swelling degree of 1.5 to 4.0 in the insoluble part, Can be mentioned.
  • the innermost hard layer polymer (a) constituting the multilayer structure acrylic granular composite is 80 to 98.9% by mass of methyl methacrylate and 1 to 20 mass of alkyl acrylate having 1 to 8 carbon atoms in the alkyl group. % And a monomer mixture consisting of 0.01 to 0.3% by mass of a polyfunctional grafting agent is preferred.
  • examples of the alkyl acrylate having 1 to 8 carbon atoms in the alkyl group include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, s-butyl acrylate, 2-ethylhexyl acrylate, and the like. And n-butyl acrylate are preferably used.
  • the proportion of the alkyl acrylate unit in the innermost hard layer polymer (a) is 1 to 20% by mass.
  • the thermal decomposability of the polymer is increased, while the unit is 20% by mass. If it exceeds 50%, the glass transition temperature of the innermost hard layer polymer (c) is lowered, and the impact resistance imparting effect of the three-layer structure acrylic granular composite is lowered.
  • polyfunctional grafting agent examples include polyfunctional monomers having different polymerizable functional groups, such as allyl esters of acrylic acid, methacrylic acid, maleic acid, and fumaric acid, and allyl methacrylate is preferably used. .
  • the polyfunctional grafting agent is used to chemically bond the innermost hard layer polymer and the soft layer polymer, and the ratio used during the innermost hard layer polymerization is 0.01 to 0.3% by mass. .
  • the crosslinked soft layer polymer (b) constituting the acrylic granular composite is an alkyl acrylate having from 9 to 8 carbon atoms having an alkyl group of 1 to 8 in the presence of the innermost hard layer polymer (a). What is obtained by polymerizing a monomer mixture consisting of 10% by mass, 0.01 to 5% by mass of a polyfunctional crosslinking agent and 0.5 to 5% by mass of a polyfunctional grafting agent is preferred.
  • n-butyl acrylate or 2-ethylhexyl acrylate is preferably used as the alkyl acrylate having 4 to 8 carbon atoms in the alkyl group.
  • Examples of other monofunctional monomers that can be copolymerized include styrene and substituted styrene derivatives. As the ratio of the alkyl acrylate having 4 to 8 carbon atoms in the alkyl group and styrene increases, the glass transition temperature of the produced polymer (b) decreases as the former increases, that is, it can be softened.
  • the refractive index of the soft layer polymer (b) at room temperature is set to the innermost hard layer polymer (a), the outermost hard layer polymer (c), and the hard heat. It is more advantageous to make it closer to the plastic acrylic resin, and the ratio between them is selected in consideration of these.
  • polyfunctional grafting agent those mentioned in the section of the innermost layer hard polymer (a) can be used.
  • the polyfunctional grafting agent used here is used to chemically bond the soft layer polymer (b) and the outermost hard layer polymer (c), and the proportion used during the innermost hard layer polymerization is impact resistance. From the viewpoint of the effect of imparting properties, 0.5 to 5% by mass is preferable.
  • polyfunctional crosslinking agent generally known crosslinking agents such as divinyl compounds, diallyl compounds, diacrylic compounds, dimethacrylic compounds and the like can be used, but polyethylene glycol diacrylate (molecular weight 200 to 600) is preferably used.
  • the polyfunctional cross-linking agent used here is used to generate a cross-linked structure during the polymerization of the soft layer (b) and to exhibit the effect of imparting impact resistance.
  • the polyfunctional crosslinking agent is not an essential component because the crosslinked structure of the soft layer (b) is generated to some extent. Is preferably 0.01 to 5% by weight from the viewpoint of imparting impact resistance.
  • the outermost hard layer polymer (c) constituting the multilayer structure acrylic granular composite is 80 to 99 mass% of methyl methacrylate in the presence of the innermost hard layer polymer (a) and the soft layer polymer (b). % And a monomer mixture comprising 1 to 20% by mass of an alkyl acrylate having 1 to 8 carbon atoms in the alkyl group is preferred.
  • alkyl acrylate those described above are used, but methyl acrylate and ethyl acrylate are preferably used.
  • the proportion of alkyl acrylate units in the outermost hard layer (c) is preferably 1 to 20% by mass.
  • an alkyl mercaptan or the like can be used as a chain transfer agent to adjust the molecular weight for the purpose of improving compatibility with the acrylic resin.
  • the outermost hard layer with a gradient such that the molecular weight gradually decreases from the inside toward the outside in order to improve the balance between elongation and impact resistance.
  • the monomer mixture for forming the outermost hard layer is divided into two or more, and the molecular weight is increased from the inside by a method of sequentially increasing the amount of chain transfer agent added each time. It is possible to make it smaller toward the outside.
  • the molecular weight formed at this time can also be examined by polymerizing the monomer mixture used each time under the same conditions, and measuring the molecular weight of the obtained polymer.
  • the particle diameter of the acrylic granular composite which is a multilayer structure polymer preferably used in the present invention is not particularly limited, but is preferably 10 nm or more and 1000 nm or less, and more preferably 20 nm or more and 500 nm or less. More preferably, it is most preferably 50 nm or more and 400 nm or less.
  • the mass ratio of the core and the shell is not particularly limited, but when the entire multilayer structure polymer is 100 parts by mass,
  • the core layer is preferably 50 parts by mass or more and 90 parts by mass or less, and more preferably 60 parts by mass or more and 80 parts by mass or less.
  • Examples of such a commercial product of a multilayer structure acrylic granular composite include, for example, “Metablene” manufactured by Mitsubishi Rayon Co., Ltd., “Kaneace” manufactured by Kaneka Chemical Co., Ltd., “Kaneha Chemical Co., Ltd.” Paraloid ”,“ Acryloid ”manufactured by Rohm and Haas Co., Ltd.,“ Staffyroid ”manufactured by Ganz Kasei Kogyo Co., Ltd.,“ Parapet SA ”manufactured by Kuraray Co., Ltd. and the like are used alone or in combination of two or more. be able to.
  • acrylic particles (c-1) which are graft copolymers preferably used as the acrylic particles preferably used in the present invention include unsaturated carboxylic acid ester series in the presence of a rubbery polymer.
  • a monomer mixture comprising a monomer, an unsaturated carboxylic acid monomer, an aromatic vinyl monomer, and, if necessary, other vinyl monomers copolymerizable therewith was copolymerized.
  • a graft copolymer is mentioned.
  • the rubbery polymer used for the acrylic particles (c-1) as the graft copolymer is not particularly limited, but diene rubber, acrylic rubber, ethylene rubber, and the like can be used.
  • polybutadiene examples include polybutadiene, styrene-butadiene copolymer, block copolymer of styrene-butadiene, acrylonitrile-butadiene copolymer, butyl acrylate-butadiene copolymer, polyisoprene, butadiene-methyl methacrylate copolymer.
  • Rubbery polymers can be used alone or in a mixture of two or more.
  • the refractive indexes of the acrylic resin and the acrylic particles are close to each other because the transparency of the acrylic resin-containing film according to the present invention can be obtained.
  • the refractive index difference between the acrylic particles and the acrylic resin is preferably 0.05 or less, more preferably 0.02 or less, and particularly preferably 0.01 or less.
  • a method for adjusting the composition ratio of each monomer unit of the acrylic resin and / or a composition ratio of the rubbery polymer or monomer used for the acrylic particles is prepared. Depending on the method, the difference in refractive index can be reduced, and an acrylic resin-containing film excellent in transparency can be obtained.
  • the refractive index difference here is a solution in which the acrylic resin-containing film according to the present invention is sufficiently dissolved in an appropriate condition in a solvent in which the acrylic resin is soluble to obtain a cloudy solution, which is subjected to an operation such as centrifugation.
  • the solvent is separated into a soluble part and an insoluble part, and after the soluble part (acrylic resin) and the insoluble part (acrylic particles) are purified, the difference in measured refractive index (23 ° C., measurement wavelength: 550 nm) is shown.
  • the method of blending the acrylic particles with the acrylic resin in the present invention is not particularly limited, and after blending the acrylic resin and other optional components in advance, usually at 200 to 350 ° C. while adding the acrylic particles, the uniaxial or A method of uniformly melt-kneading with a twin-screw extruder is preferably used from the viewpoint of excellent transparency by avoiding aggregation of a plurality of acrylic particles.
  • a method such as in-line addition can be used.
  • acrylic particles can also be used as the acrylic particles according to the present invention.
  • metabrene W-341 (manufactured by Mitsubishi Rayon Co., Ltd.)
  • Chemisnow MR-2G (C3)
  • MS-300X (manufactured by Soken Chemical Co., Ltd.) and the like can be mentioned.
  • the acrylic resin-containing film according to the present invention preferably contains 0.5 to 45% by mass of acrylic particles with respect to the total mass of the resin constituting the film.
  • moisture permeability inhibitor examples include phthalate ester, fatty acid ester, trimellitic ester, phosphoric ester, polyester, and epoxy.
  • polyester and phthalate ester moisture permeability inhibitors are preferably used.
  • Polyester moisture permeability inhibitors are superior in non-migration and extraction resistance compared to phthalate ester moisture permeability inhibitors such as dioctyl phthalate. Therefore, it is applicable to a wide range of uses by selecting or using these moisture permeability inhibitors according to the use.
  • the polyester-based moisture permeability inhibitor is a reaction product of a monovalent or tetravalent carboxylic acid and a monovalent or hexavalent alcohol, and is mainly obtained by reacting a divalent carboxylic acid with a glycol. Used.
  • divalent carboxylic acids include glutaric acid, itaconic acid, adipic acid, phthalic acid, azelaic acid, sebacic acid and the like.
  • glycol examples include glycols such as ethylene, propylene, 1,3-butylene, 1,4-butylene, 1,6-hexamethylene, neopentylene, diethylene, triethylene, and dipropylene. These divalent carboxylic acids and glycols may be used alone or in combination.
  • the ester-based moisture permeation suppressor may be any of ester, oligoester, and polyester types, and the molecular weight is preferably in the range of 100 to 10,000, and more preferably in the range of 600 to 3000, which has a greater plasticizing effect.
  • the viscosity of the moisture permeability inhibitor has a correlation with the molecular structure and molecular weight, but in the case of an adipic acid moisture permeability inhibitor, a range of 200 to 5000 mPa ⁇ s (25 ° C.) is preferable in view of compatibility and plasticization efficiency. . Further, some polyester moisture permeability inhibitors may be used in combination.
  • the moisture permeability inhibitor is preferably added in an amount of 0.5 to 30 parts by mass with respect to 100 parts by mass of the composition containing an acrylic resin. If the amount of the moisture permeability inhibitor exceeds 30 parts by mass, the surface becomes sticky, which is not preferable for practical use.
  • the moisture permeability at 60 ° C. and 95% RH of the film constituting the first optically anisotropic layer needs to be in the range of 20 to 600 g / m 2 ⁇ 24 h.
  • the cellulose ester resin is selected as the moisture permeability improving agent within the above composition range.
  • the cellulose ester resin used for the second optically anisotropic layer and the cellulose ester resin used for the first optically anisotropic layer of the present invention have the respective purposes of the second optically anisotropic layer and the first optically anisotropic layer. They can be selected within the range to be satisfied, and these may be the same or different.
  • composition containing the acrylic resin according to the present invention preferably contains an ultraviolet absorber, and examples of the ultraviolet absorber used include benzotriazole, 2-hydroxybenzophenone, or salicylic acid phenyl ester. .
  • 2- (5-methyl-2-hydroxyphenyl) benzotriazole 2- [2-hydroxy-3,5-bis ( ⁇ , ⁇ -dimethylbenzyl) phenyl] -2H-benzotriazole
  • 2- (3 Triazoles such as 5-di-t-butyl-2-hydroxyphenyl) benzotriazole, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone And benzophenones.
  • ultraviolet absorbers having a molecular weight of 400 or more are less likely to volatilize at a high boiling point and are difficult to disperse even during high-temperature molding, so that the weather resistance is effectively improved with a relatively small amount of addition. be able to.
  • the transition from the thin coating layer to the substrate layer is particularly small and hardly precipitates on the surface of the laminate, the amount of contained UV absorber is maintained for a long time, and the durability of the weather resistance improvement effect is excellent. From the point of view, it is preferable.
  • Examples of the ultraviolet absorber having a molecular weight of 400 or more include 2- [2-hydroxy-3,5-bis ( ⁇ , ⁇ -dimethylbenzyl) phenyl] -2-benzotriazole, 2,2-methylenebis [4- (1, 1,3,3-tetrabutyl) -6- (2H-benzotriazol-2-yl) phenol], bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis ( Hindered amines such as 1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonic acid Bis (1,2,2,6,6-pentamethyl-4-piperidyl), 1- [2- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] Such as til] -4- [3- (3,5-di-tert-butyl
  • antioxidants may be added to the acrylic resin used in the acrylic resin-containing film according to the present invention in order to improve the thermal decomposability and thermal colorability during molding.
  • a flame retardant acrylic resin composition containing a phosphorus flame retardant may be used.
  • Phosphorus flame retardants used here include red phosphorus, triaryl phosphate ester, diaryl phosphate ester, monoaryl phosphate ester, aryl phosphonate compound, aryl phosphine oxide compound, condensed aryl phosphate ester, halogenated alkyl phosphorus. Examples thereof include one or a mixture of two or more selected from acid esters, halogen-containing condensed phosphates, halogen-containing condensed phosphonates, halogen-containing phosphites, and the like.
  • triphenyl phosphate 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, phenylphosphonic acid, tris ( ⁇ -chloroethyl) phosphate, tris (dichloropropyl) Examples thereof include phosphate and tris (tribromoneopentyl) phosphate.
  • an acrylic resin-containing film As a method for producing an acrylic resin-containing film according to the present invention, production methods such as an inflation method, a T-die method, a calendar method, a cutting method, a casting method, an emulsion method, and a hot press method can be used. From the viewpoints of suppressing foreign matter defects and optical defects such as die lines, solution casting by casting is preferred. Using a cellulose resin blended with an acrylic resin is preferable from the viewpoint of improving the drying property of the solvent when the step of producing a film is solution casting. Further, since the completed film has an appropriate moisture permeability, the object of the present invention can be effectively expressed.
  • Organic solvent used for forming the dope when the acrylic resin-containing film according to the present invention is produced by the solution casting method is limited as long as it dissolves acrylic resin, cellulose ester resin, and other additives simultaneously. Can be used.
  • methylene chloride as a non-chlorinated organic solvent, methyl acetate, ethyl acetate, amyl acetate, acetone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-hexafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro- 2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, etc.
  • Methylene chloride, methyl acetate, ethyl acetate and acetone can be preferably used.
  • the dope preferably contains 1 to 40% by mass of a linear or branched aliphatic alcohol having 1 to 4 carbon atoms.
  • the web gels and peeling from the metal support becomes easy, and when the proportion of alcohol is small, the acrylic resin and cellulose ester resin dissolve in a non-chlorine organic solvent system. There is also a role to promote.
  • the dope composition is dissolved in%.
  • linear or branched aliphatic alcohol having 1 to 4 carbon atoms examples include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, and tert-butanol. Ethanol is preferred because of the stability of these dopes, the relatively low boiling point, and good drying properties.
  • a method carried out at normal pressure a method carried out below the boiling point of the main solvent, a method carried out under pressure above the boiling point of the main solvent, JP-A-9-95544 and JP-A-9-
  • Various dissolution methods can be used such as a method performed by a cooling dissolution method as described in JP-A-95557 or JP-A-9-95538, a method performed at high pressure as described in JP-A No. 11-21379,
  • a method of pressurizing at a temperature equal to or higher than the boiling point of the main solvent is preferable.
  • the total amount of acrylic resin and cellulose ester resin in the dope is preferably 15 to 45% by mass.
  • An additive is added to the dope during or after dissolution to dissolve and disperse, then filtered through a filter medium, defoamed, and sent to the next step with a liquid feed pump.
  • a filter medium having a collected particle diameter of 0.5 to 5 ⁇ m and a drainage time of 10 to 25 sec / 100 ml.
  • agglomerates remaining at the time of particle dispersion and agglomerates generated upon addition of the main dope are only aggregated by using a filter medium having a collected particle diameter of 0.5 to 5 ⁇ m and a drainage time of 10 to 25 sec / 100 ml. Can be removed.
  • the concentration of particles is sufficiently thinner than that of the additive solution, so that the aggregates do not stick together during filtration and the filtration pressure does not increase suddenly.
  • FIG. 1 is a diagram schematically showing a dope preparation step, a casting step, and a drying step of a solution casting film forming method preferable for the present invention.
  • the main dope solution is filtered by the main filter 3, and an ultraviolet absorbent additive solution is added in-line from 16 to this.
  • the main dope may contain about 10 to 50% by weight of recycled material.
  • the return material may contain acrylic particles. In that case, it is preferable to control the addition amount of the acrylic particle addition liquid in accordance with the addition amount of the return material.
  • the additive solution containing acrylic particles preferably contains 0.5 to 10% by mass of acrylic particles, more preferably 1 to 10% by mass, and more preferably 1 to 5% by mass. Most preferably.
  • Recycled material is a finely pulverized acrylic resin-containing film that is generated when an acrylic resin-containing film is formed.
  • the original fabric is used.
  • an acrylic resin, a cellulose ester resin, and in some cases, acrylic particles kneaded into pellets can be preferably used.
  • An endless metal belt 31 such as a stainless steel belt or a rotating metal drum, which feeds the dope through a liquid feed pump (for example, a pressurized metering gear pump) to the pressure die 30 and transfers it infinitely. This is a step of casting the dope from the pressure die slit to the casting position on the support.
  • a liquid feed pump for example, a pressurized metering gear pump
  • the pressure die includes a coat hanger die and a T die, and any of them is preferably used.
  • the surface of the metal support is a mirror surface.
  • two or more pressure dies may be provided on the metal support, and the dope amount may be divided and stacked. Or it is also preferable to obtain the film of a laminated structure by the co-casting method which casts several dope simultaneously.
  • Solvent evaporation step In this step, the web (the dope is cast on the casting support and the formed dope film is called a web) is heated on the casting support to evaporate the solvent.
  • the web on the support after casting is preferably dried on the support in an atmosphere of 40 to 100 ° C.
  • Peeling process It is the process of peeling the web which the solvent evaporated on the metal support body in a peeling position. The peeled web is sent to the next process.
  • the temperature at the peeling position on the metal support is preferably 10 to 40 ° C., more preferably 11 to 30 ° C.
  • the residual solvent amount at the time of peeling of the web on the metal support at the time of peeling is preferably peeled in the range of 50 to 120% by mass depending on the strength of drying conditions, the length of the metal support, and the like.
  • the amount of residual solvent is determined.
  • the amount of residual solvent in the web is defined by the following formula.
  • Residual solvent amount (%) (mass before web heat treatment ⁇ mass after web heat treatment) / (mass after web heat treatment) ⁇ 100 Note that the heat treatment for measuring the residual solvent amount represents performing heat treatment at 115 ° C. for 1 hour.
  • the peeling tension at the time of peeling the metal support from the film is usually 196 to 245 N / m. However, if wrinkles easily occur at the time of peeling, it is preferable to peel with a tension of 190 N / m or less. It is preferable to peel at a minimum tension of ⁇ 166.6 N / m, and then peel at a minimum tension of ⁇ 137.2 N / m, and particularly preferable to peel at a minimum tension of ⁇ 100 N / m.
  • the temperature at the peeling position on the metal support is preferably ⁇ 50 to 40 ° C., more preferably 10 to 40 ° C., and most preferably 15 to 30 ° C.
  • a drying device 35 that transports the web alternately through rolls arranged in the drying device and / or a tenter stretching device 34 that clips and transports both ends of the web with clips. And dry the web.
  • the drying means is generally to blow hot air on both sides of the web, but there is also a means to heat by applying microwaves instead of wind. Too rapid drying tends to impair the flatness of the finished film. Drying at a high temperature is preferably performed from about 8% by mass or less of residual solvent. Throughout, drying is generally performed at 40-250 ° C. In particular, drying at 40 to 160 ° C. is preferable.
  • tenter stretching apparatus When using a tenter stretching apparatus, it is preferable to use an apparatus that can independently control the film gripping length (distance from the start of gripping to the end of gripping) left and right by the left and right gripping means of the tenter. In the tenter process, it is also preferable to intentionally create sections having different temperatures in order to improve planarity.
  • the stretching operation may be performed in multiple stages, and it is also preferable to perform biaxial stretching in the casting direction and the width direction.
  • biaxial stretching When biaxial stretching is performed, simultaneous biaxial stretching may be performed or may be performed stepwise.
  • stepwise means that, for example, stretching in different stretching directions can be sequentially performed, stretching in the same direction is divided into multiple stages, and stretching in different directions is added to any one of the stages. Is also possible. That is, for example, the following stretching steps are possible.
  • Simultaneous biaxial stretching includes stretching in one direction and contracting the other while relaxing the tension.
  • the preferred draw ratio for simultaneous biaxial stretching can be in the range of x1.01 to x1.5 in both the width direction and the longitudinal direction.
  • the amount of residual solvent in the web is preferably 20 to 100% by mass at the start of the tenter, and drying is preferably performed while the tenter is applied until the amount of residual solvent in the web is 10% by mass or less. More preferably, it is 5% by mass or less.
  • the drying temperature is preferably 30 to 150 ° C, more preferably 50 to 120 ° C, and most preferably 70 to 100 ° C.
  • the temperature distribution in the width direction of the atmosphere is small from the viewpoint of improving the uniformity of the film.
  • the temperature distribution in the width direction in the tenter process is preferably within ⁇ 5 ° C, and within ⁇ 2 ° C. Is more preferable, and within ⁇ 1 ° C. is most preferable.
  • Winding step This is a step of winding up the acrylic resin-containing film by the winder 37 after the residual solvent amount in the web is 2% by mass or less, and by setting the residual solvent amount to 0.4% by mass or less. A film having good dimensional stability can be obtained.
  • a generally used one may be used, and there are a constant torque method, a constant tension method, a taper tension method, a program tension control method with a constant internal stress, etc., and these may be used properly.
  • the acrylic resin-containing film according to the present invention is preferably a long film.
  • the acrylic resin-containing film has a thickness of about 100 m to 5000 m and is usually provided in a roll shape.
  • the film width is preferably 1.3 to 4 m, more preferably 1.4 to 2 m.
  • stretching using a tenter is preferable from the viewpoint of smoothing the surface of the film during the production of a long film, and there is no unevenness of stretching by making the stretching ratio in the width direction larger than the stretching ratio in the film forming direction. It is excellent in that a film can be obtained.
  • the in-plane refractive index of the long film obtained in this production process is minimized in the width direction, the fast axis coincides with the width direction, and the slow axis coincides with the film forming direction.
  • the polarizing plate of the present invention is characterized in that the adhesive layer is provided between the second optical anisotropic layer and the first optical anisotropic layer.
  • the “adhesion layer” refers to an adhesion imparting layer for bonding the second optical anisotropic layer and the first optical anisotropic layer, respectively, among the adhesion imparting layers.
  • cellulose esters such as cellulose triacetate, cellulose diacetate, cellulose acetate propionate, and cellulose acetate butyrate
  • hydrophilic cellulose derivatives for example, methylcellulose, carboxymethylcellulose, hydroxycellulose, etc.
  • Polyvinyl alcohol derivatives eg, polyvinyl alcohol, vinyl acetate-vinyl alcohol copolymer, polyvinyl acetal, polyvinyl formal, polyvinyl benzal, etc.
  • natural polymer compounds eg, gelatin, casein, gum arabic, etc.
  • hydrophilic polyester Derivatives eg, partially sulfonated polyethylene terephthalate
  • hydrophilic polyvinyl derivatives eg, poly-N-vinylpyrrole) Pyrrolidone, polyacrylamide, polyvinyl indazole, polyvinyl pyrazole, etc.
  • the solvent used for coating the adhesion-imparting layer it is effective to increase the mixing ratio of the solvent to be dissolved or the solvent to be swollen and to decrease the ratio of the solvent that is not dissolved.
  • Examples of the solvent for dissolving or swelling the protective film for polarizing plate contained in such a mixed composition include dioxane, acetone, methyl ethyl ketone, N, N-dimethylformamide, methyl acetate, ethyl acetate, trichloroethylene, methylene chloride, Examples include ethylene chloride, tetrachloroethane, trichloroethane, and chloroform.
  • Examples of the solvent that does not dissolve include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butanol, and hydrocarbons (toluene, xylene, cyclohexanol).
  • these coating compositions are applied to the surface of the protective film for a polarizing plate using a gravure coater, dip coater, reverse coater, wire bar coater, die coater or the like so that the film thickness after drying is 0.1 to 2 ⁇ m.
  • the film thickness is preferably 0.1 to 1.0 ⁇ m.
  • the adhesion-imparting layer may flow out into the aqueous alkaline solution.
  • a crosslinking agent may be used in the adhesion-imparting layer, and an isocyanate-based crosslinking agent is preferably used.
  • the surface of the film is hydrolyzed, and this can be used as an adhesion-imparting layer.
  • adhesion between the polarizer and the polarizing plate protective film it is important that the adhesion providing layer is present on the surface of the film.
  • the temperature for drying the coating solution is preferably 80 to 120 ° C., more preferably 100 to 110 ° C.
  • an adhesive is used to bond the polarizer and the polarizing plate protective film, the polarizer and the second optical anisotropic layer, and the second optical anisotropic layer and the first optical anisotropic layer, respectively.
  • the storage elastic modulus at 25 ° C. of the layer coated with the adhesive is preferably in the range of 1.0 ⁇ 10 4 Pa to 1.0 ⁇ 10 9 Pa.
  • the adhesive is a polarizer and a polarizing plate protective film, A coating solution containing an adhesive is applied to at least one of the bonding surfaces of the polarizer and the second optical anisotropic layer, and the second optical anisotropic layer and the first optical anisotropic layer, and bonded by adhesion. can do.
  • the polarizing plate protective film In order to uniformly apply the adhesive coating solution, as described above, the polarizing plate protective film, the film that is the second optical anisotropic layer, and at least one surface of the first optical anisotropic layer, It is preferable to install or treat an adhesion-imparting layer. Moreover, it can corona-treat and can apply
  • the drying temperature is preferably 70 ° C. or less, and 65 ° C. or less from the viewpoint of not causing uneven polarization of the polarizer. Preferably there is.
  • the drying temperature is preferably 30 ° C. or higher, preferably 35 ° C. or higher, more preferably 40 ° C. or higher.
  • a curable pressure-sensitive adhesive that forms a high molecular weight body or a crosslinked structure by various chemical reactions after being bonded may also be used.
  • urethane adhesives examples include, for example, urethane adhesives, epoxy adhesives, aqueous polymer-isocyanate adhesives, curable adhesives such as thermosetting acrylic adhesives, moisture curable urethane adhesives, polyether methacrylate types, Examples include anaerobic adhesives such as ester-based methacrylate type and oxidized polyether methacrylate, cyanoacrylate-based instant adhesives, acrylate-peroxide-based two-component instant adhesives, and the like.
  • the adhesive may be a one-component type, or a type in which two or more components are mixed before use.
  • the adhesive solution is a solvent mainly composed of water, or the solvent of the adhesive dispersion is mainly composed of water. preferable.
  • the adhesive whose solvent is mainly water is preferably an aqueous type such as an emulsion type, a colloidal dispersion type, or an aqueous solution type.
  • an aqueous solution of a polyvinyl alcohol derivative or an adhesive using a water-dispersible urethane adhesive and a crosslinking agent in combination is particularly preferred.
  • the concentration of the liquid containing the adhesive may be appropriately determined depending on the film thickness of the adhesive layer, the application method, the application conditions, and the like, and is usually 0.1 to 50% by mass.
  • the film thickness of the adhesive layer is preferably 5 nm to 10 ⁇ m, more preferably 10 nm to 5 ⁇ m, and the refractive index of the adhesive layer between the interface of the adjacent film as viewed from the adhesive layer is the same, or the refractive index difference is 0.01 or less. It is preferable from the viewpoint of light transmission. When the difference in refractive index is large and the film thickness of the adhesive layer is large, the light transmittance decreases due to reflection.
  • the polarizing plate of the present invention is characterized by being attached to a glass substrate of a liquid crystal cell via an adhesive layer.
  • the thickness of the adhesive layer is preferably 5 ⁇ m to 50 ⁇ m, more preferably 10 ⁇ m to 30 ⁇ m.
  • the pressure-sensitive adhesive layer can be previously installed on the polarizing plate, and the polarizing plate can be bonded to the liquid crystal cell.
  • the pressure-sensitive adhesive layer is preferably a water-dispersed pressure-sensitive adhesive from the viewpoint of maintaining the degree of polarization.
  • a water-dispersible pressure-sensitive adhesive is coated on the polarizing plate, and the pressure-sensitive adhesive layer is placed on the polarizing plate by drying. After the adhesive layer is placed on the peelable film, the adhesive layer may be transferred to the polarizing plate of the present invention. This is because in the production process of the polarizing plate, when there is some solvent remaining in the pressure-sensitive adhesive layer, the degree of polarization of the polarizer can be maintained by using water rather than the organic solvent.
  • Various water-dispersed pressure-sensitive adhesives such as rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, and silicone-based pressure-sensitive adhesives can be used as water-dispersible pressure-sensitive adhesives, but they are colorless and transparent, and have adhesion to liquid crystal cells (glass substrates).
  • a preferable acrylic pressure-sensitive adhesive is preferable.
  • the polarizing plate of the present invention is a polarizing plate having at least a first optical anisotropic layer and a second optical anisotropic layer, and is an adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic. It is characterized by comprising in the order of a functional layer / a polarizer.
  • an iodine-based polarizer As the polarizer, an iodine-based polarizer, a dye-based polarizer using a dichroic dye, or a polyene-based polarizer can be used.
  • Iodine polarizer and dye polarizer are generally produced using a polyvinyl alcohol film.
  • the absorption axis of the polarizer corresponds to the stretching direction of the film. Accordingly, a polarizer stretched in the longitudinal direction (transport direction) has an absorption axis parallel to the longitudinal direction, and a polarizer stretched in the lateral direction (perpendicular to the transport direction) is perpendicular to the longitudinal direction. Has an absorption axis.
  • a preferred method for producing the polarizing plate of the present invention includes a step of successively laminating a polarizer and a retardation film in a long state.
  • the long polarizing plate is cut according to the screen size of the liquid crystal display device used.
  • a polarizer generally has a protective film on both surfaces.
  • the cellulose ester film contained in the retardation film according to the present invention can function as a protective film for the polarizer.
  • a protective film is separately attached to the surface of the polarizer on the retardation film side. There is no need.
  • the polarizing plate protective film sandwiched between the polarizers on the observation side and the light source side is an optically isotropic adhesive layer and / or optically other than the film constituting the present invention. It is preferable that an isotropic transparent protective film is included.
  • the optically isotropic transparent protective film is specifically a film having an in-plane retardation Ro of -10 to 0 to 10 nm and a thickness direction retardation Rt of -20 to 20 nm.
  • a film containing cellulose ester or cyclic polyolefin, or a film containing acrylic resin is preferred.
  • the first optical anisotropic layer, the second optical anisotropic layer, and the polarizer are laminated in this order, and the second optical anisotropic layer of the second optical anisotropic layer In the polarizing plate, the direction of the slow axis and the direction of the absorption axis of the polarizer are substantially orthogonal.
  • the direction of the slow axis of the second optically anisotropic layer made of a specific cellulose ester film can be adjusted by the stretching direction when the cellulose ester film is produced.
  • the moisture permeability of the film constituting the first optical anisotropic layer at 60 ° C. and 95% RH is in the range of 20 to 600 g / m 2 ⁇ 24 h, and constitutes the second optical anisotropic layer. It is excellent from the following viewpoint that the moisture permeability of the film is 600 to 1500 g / m 2 ⁇ 24 h.
  • the polarizing plate of the present invention is used in the configuration of the pressure-sensitive adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic layer / polarizer.
  • the polarizing plate having the configuration of the first optically anisotropic layer / adhesive layer / second optically anisotropic layer / polarizer / cellulose-based polarizing plate protective film is the second optically anisotropic layer / polarizer /
  • a primary polarizing plate is prepared with the structure of a cellulose-based polarizing plate protective film, and then, the first optical anisotropic layer / adhesive layer / second optical anisotropic layer / polarizer / cellulose-based polarizing plate protective film is formed. It is preferable to produce a polarizing plate in which a film of the first optical anisotropic layer is disposed via an adhesive layer.
  • the moisture permeability of the second optically anisotropic layer is 600 to 1500 g / m 2 ⁇ at 60 ° C. and 95% RH. It is necessary from a viewpoint of the drying property of the manufacturing process of a polarizing plate that it is 24h.
  • the adhesive layer can be coated with an adhesive using water or an organic solvent, or a combination of water and an organic solvent. At this time, it is necessary to dry the water or the organic solvent used for coating the adhesive layer.
  • the liquid crystal display device of the present invention includes at least the polarizing plate of the present invention.
  • the liquid crystal display device of the present invention may be any of a reflection type, a semi-transmission type, a transmission type liquid crystal display device and the like.
  • a liquid crystal display device generally includes a polarizing plate, a liquid crystal cell, and, if necessary, a retardation plate, a reflective layer, a light diffusion layer, a backlight, a front light, a light control film, a light guide plate, a prism sheet, a color filter, etc.
  • a retardation plate for adjusting the polarization of the present invention.
  • the liquid crystal cell is not particularly limited, and a general liquid crystal cell such as a liquid crystal layer sandwiched between a pair of transparent substrates provided with electrodes can be used.
  • the transparent substrate constituting the liquid crystal cell is not particularly limited as long as the liquid crystal material constituting the liquid crystal layer is aligned in a specific alignment direction.
  • a transparent substrate in which the substrate itself has a property of orienting liquid crystals a transparent substrate in which an alignment film having the property of orienting liquid crystals is provided, but the substrate itself lacks the alignment ability. Either can be used.
  • known electrodes can be used for the electrodes of the liquid crystal cell. Usually, it can be provided on the surface of the transparent substrate in contact with the liquid crystal layer, and when a substrate having an alignment film is used, it can be provided between the substrate and the alignment film.
  • the material exhibiting liquid crystallinity for forming the liquid crystal layer is not particularly limited, and examples thereof include various ordinary low-molecular liquid crystalline compounds, high-molecular liquid crystalline compounds, and mixtures thereof that can constitute various liquid crystal cells. Moreover, a pigment
  • the liquid crystal cell may include various components necessary for forming various types of liquid crystal cells described later.
  • liquid crystal cell method a TN (Twisted Nematic) method, a STN (Super Twisted Nematic) method, an ECB (Electrically Controlled Birefringence) method, an IPS (In-Plane Switching) method, a VA (In-Plane Switching) method, a VA (In-Plane Switching) method, a VA (In-Plane Switching) method, and a VA (In-Plane Switching) method.
  • TN Transmission Nematic
  • STN Super Twisted Nematic
  • ECB Electrically Controlled Birefringence
  • IPS In-Plane Switching
  • VA In-Plane Switching
  • VA In-Plane Switching
  • VA In-Plane Switching
  • VA In-Plane Switching
  • VA In-Plane Switching
  • PVA Vertical Alignment
  • PVA Power Planar Alignment
  • OCB Optically Compensated Bend
  • HAN Hybrid Aligned Nematic
  • ASM Ocell ASM Ocell method
  • a halftone gray scale method the domain division method or a ferroelectric liquid crystal
  • various methods such as a display system using an antiferroelectric liquid crystal and the like.
  • the liquid crystal cell driving method is not particularly limited, and a passive matrix method used for STN-LCD and the like, and an active matrix method using an active electrode such as a TFT (Thin Film Transistor) electrode and a TFD (Thin Film Diode) electrode, Any driving method such as a plasma addressing method may be used.
  • a field sequential method that does not use a color filter may be used.
  • the polarizing plate of the present invention is preferably used for reflective, transflective, and transmissive liquid crystal display devices.
  • a reflective liquid crystal display device usually has a configuration in which a reflector, a liquid crystal cell, and a polarizing plate are laminated in this order.
  • the retardation plate is disposed between the reflector and the polarizer (between the reflector and the liquid crystal cell or between the liquid crystal cell and the polarizer).
  • the reflective plate may share the liquid crystal cell and the substrate.
  • the polarizing plate the polarizing plate of the present invention can be used. In such a case, the retardation plate may not be separately provided.
  • the transflective liquid crystal display device includes a liquid crystal cell, a polarizing plate disposed on the viewer side of the liquid crystal cell, and at least one retardation plate disposed between the polarizing plate and the liquid crystal cell. And at least one transflective layer disposed behind the liquid crystal layer as viewed from the viewer, and at least one retardation plate and polarizing plate behind the transflective layer as viewed from the viewer And have.
  • This type of liquid crystal display device can be used in both reflection mode and transmission mode by installing a backlight.
  • Both polarizing plates may be the polarizing plate of the present invention, or only one of them may be the polarizing plate of the present invention.
  • a retardation plate may not be separately disposed between the liquid crystal cell and the polarizing plate of the present invention.
  • the mode of the liquid crystal cell is not particularly limited, but is preferably an IPS mode or an FFS mode.
  • rod-like liquid crystal molecules are aligned substantially parallel to the substrate, and the liquid crystal molecules respond in a planar manner when an electric field parallel to the substrate surface is applied.
  • JP-A-10-54982, JP-A-11-202323, and JP-A-9-292522 are methods for reducing leakage light during black display in an oblique direction and improving a viewing angle using a retardation film.
  • the polarizing plate according to the first aspect includes a pair of substrates and a liquid crystal cell in which liquid crystal molecules sandwiched between the pair of substrates are aligned substantially parallel to the substrate during black display.
  • a liquid crystal display device having a liquid crystal cell for example, an IPS mode liquid crystal cell
  • the first optical anisotropic layer and the second optical anisotropic layer are formed on the outer side of one of the pair of substrates from the substrate side.
  • the polarizer is arranged in this order, and the polarizing plate is arranged so that the slow axis of the second optically anisotropic layer and the major axis direction of the liquid crystal molecules during black display are substantially parallel
  • a second polarizer can be further disposed outside the other substrate. In this case, the absorption axes of both polarizers are arranged so as to be orthogonal to each other.
  • the polarizing plate of the second aspect includes a pair of substrates and a liquid crystal layer in which liquid crystal molecules sandwiched between the pair of substrates are aligned substantially parallel to the substrate during black display.
  • the second optical anisotropic layer and the first optical anisotropic layer are formed on the outside of one of the pair of substrates from the substrate side.
  • the polarizer is arranged in this order, and the polarizing plate is arranged so that the slow axis of the second optically anisotropic layer and the major axis direction of the liquid crystal molecules at the time of black display are substantially perpendicular to each other, and A second polarizer can be further arranged outside the other substrate.
  • the polarizers are arranged so that the absorption axes of both polarizers are orthogonal to each other. Also in this case, both polarizers are arranged so that the absorption axes thereof are orthogonal to each other.
  • a substantially isotropic adhesive layer and / or a substantially isotropic transparent protective film is included between the second polarizer and the substrate. Is preferred.
  • Example 1 Provided optically anisotropic layer (B1))
  • a cellulose ester film corresponding to the second optically anisotropic layer (B1) was produced as follows.
  • a dope (cellulose ester solution) having the following composition was prepared.
  • Cellulose ester dope composition Cellulose acetate propionate CE1 100 parts by mass (acetyl group substitution degree (A) 1.95, propionyl group substitution degree (B) 0.7) Triphenyl phosphate 10 parts by weight Ethylphthalylethyl glycolate 2 parts by weight Tinuvin 326 (manufactured by Ciba Japan) 1 part by weight AEROSIL 200V (manufactured by Nippon Aerosil Co., Ltd.) 0.1 part by weight Methylene chloride 300 parts by weight Ethanol 40 parts by mass The above composition was sufficiently dissolved while heating to prepare a dope solution.
  • the dope solution was uniformly cast on a stainless steel band support at a temperature of 22 ° C. and a width of 2 m using a belt casting apparatus. With the stainless steel band support, the solvent was evaporated until the amount of residual solvent reached 100%, and peeling was performed from the stainless steel band support with a peeling tension of 162 N / m.
  • the web of the peeled film material was evaporated at 35 ° C., slit to 1.6 m width, and then dried at a drying temperature of 165 ° C. while being stretched 1.4 times in the width direction (TD) with a tenter. It was.
  • the residual solvent amount when starting stretching with a tenter was 10%.
  • the draw ratio in the film forming direction (MD) calculated from the rotational speed of the stainless steel band support and the operating speed of the tenter was 1.02.
  • the residual solvent amount of the film CE1 as an optically anisotropic layer described in Table 2 was 0.1%, and the film thickness was 60 ⁇ m.
  • a film B2 and a film B3 were prepared in the same manner as described in Table 1, except that the draw ratio and the draw temperature when producing the film B1 were changed.
  • Cellulose acetate CE2 100 parts by mass (acetyl group substitution degree 2.85) Triphenyl phosphate (TPP) 7.8 parts by mass Biphenyl diphenyl phosphate (BDP) 3.9 parts by mass
  • TPP Triphenyl phosphate
  • BDP Biphenyl diphenyl phosphate
  • the following retardation increasing agent 5.0 parts by mass Tinuvin 326 (manufactured by Ciba Japan Co., Ltd.) 1.0 part by mass Matt Agent (silicon dioxide (primary particle diameter 20 nm), Mohs hardness about 7)
  • 0.05 parts by weight Methylene chloride 300 parts by weight Methanol 54 parts by weight 1-butanol 11 parts by weight
  • the film was formed in the same manner as the films B1 to 3, except that the draw ratios and stretch temperatures shown in Table 1 were changed.
  • films B4 to B6 used in the present invention and comparative film B7 were produced.
  • ZEONOR film is a 200 ⁇ m thick ZEONOR film ZF-14 made of alicyclic olefin resin (glass transition temperature 136 ° C.) using a simultaneous biaxial stretching machine.
  • the film is simultaneously biaxially stretched at an oven temperature (preheating temperature, stretching temperature, heat setting temperature) of 138 ° C., a film feeding speed of 1 m / min, a longitudinal stretching ratio of 1.6 times, and a transverse stretching ratio of 1.7 times.
  • a 65 ⁇ m alicyclic olefin resin film of ZEONOR 1 was drawn and produced, and similarly changed as shown in TABLE 1 to produce ZEONOR 2.
  • Example 2 ⁇ Production of Films (P1) to (P4) as First Optical Anisotropic Layer> (First optical anisotropic layer (P1))
  • the following acrylic resins A1-A3 were prepared by a known method.
  • A1: Poly (MMA-St) mass ratio 60:40 Mw 300000 A2: Poly (MMA-St-AN) mass ratio 55:35:10 Mw 300000 A3: Poly (MMA-CHMI-St-AN) Mass ratio 90: 5: 5: 5 Mw 140000 MMA: Methyl methacrylate St: Styrene AN: Acrylonitrile CHMI: Cyclohexylmaleimide ⁇ Production of optical film P1> (Dope solution composition) Acrylic resin A2 79 parts by mass CAP482-20 (acyl group total substitution degree 2.75, acetyl group substitution degree 0.19, propionyl group substitution degree 2.56, Mw 200000 manufactured by Eastman Chemical Co., Ltd.) 20 parts by mass Acrylic particles (C1) prepared in 1 part by weight Methylene chloride 300 parts by weight Ethanol 40 parts by weight The above composition was sufficiently dissolved while heating to prepare a dope solution.
  • a small amount of the polymer latex thus obtained was collected, and the flat particle size was determined by the absorbance method, which was 0.10 ⁇ m.
  • the remaining latex was put into a 3% by mass sodium sulfate warm aqueous solution, salted out and coagulated, and then dried after repeated dehydration and washing to obtain acrylic particles (C1) having a three-layer structure.
  • the produced dope liquid was uniformly cast on a stainless steel band support at a temperature of 22 ° C. and a width of 2 m using a belt casting apparatus. With the stainless steel band support, the solvent was evaporated until the residual solvent amount reached 100%, and the film was peeled off from the stainless steel band support with a peeling tension of 162 N / m.
  • the peeled acrylic resin web was evaporated at 35 ° C., slit to 1.6 m width, and then dried at a drying temperature of 135 ° C. while being stretched 1.35 times in the width direction (TD direction) with a tenter. I let you.
  • the residual solvent amount when starting stretching with a tenter was 10%.
  • the draw ratio in the film forming direction (MD) calculated from the rotational speed of the stainless steel band support and the operating speed of the tenter was 1.3 times.
  • the residual solvent amount of the optical film P1 described in Table 2 was 0.1%, and the film thickness was 40 ⁇ m.
  • Optical films P2 to P5 were produced.
  • Example 3 ⁇ Production of polarizing plates (PL1 to PL13)> A 120- ⁇ m long roll of polyvinyl alcohol film is immersed in 100 parts by mass of an aqueous solution containing 1 part by mass of iodine and 4 parts by mass of boric acid, stretched in the transport direction 5 times at 50 ° C., and dried to make a polarizer. It was.
  • urethane resin-based aqueous emulsion is used as an adhesive on one side, and one side of film B3, which is the second optically anisotropic layer, is subjected to corona treatment and used as an adhesive to bond the aqueous emulsion with a polarizer. .
  • Aqueous emulsion of urethane resin (Hydran AP-20, manufactured by Dainippon Ink & Chemicals, Inc.) 100 parts by mass Polyfunctional glycidyl ether (CR-5L, manufactured by Dainippon Ink & Chemicals, Inc.) 5 parts by mass
  • the two films were bonded together and dried according to a conventional method to prepare polarizing plate PL1.
  • an adhesive and water are mainly formed from the end of the laminate of the polarizer and the optical film B which is a polarizing plate protective film on each side and 4UY which is a TAC film.
  • the solvent and bubbles were removed and pasted together. Bonding was performed at a roller pressure of 20 to 30 N / cm 2 and a speed of about 2 m / min. Next, the bonded sample was dried for 7 minutes in a dryer at 80 ° C. to prepare the base of the polarizing plate PL1.
  • the optical film B3 side is subjected to a corona treatment, and then the surface of the optical film P1 to be bonded to the base of PL1 is subjected to a corona treatment.
  • attached on the base of PL1 was produced by bonding and drying similarly to the above using the aqueous
  • the absorption axis of the polarizer is parallel to the longitudinal direction, and the angle formed by the absorption axis of the polarizer and the slow axis of the second optical anisotropic layer (cellulose ester film) is 90 °. there were.
  • ⁇ Production of cellulose acetate film (T0)> The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose triacetate solution U.
  • cellulose triacetate solution U Cellulose triacetate having a degree of acetyl substitution of 2.94 100 parts by mass Methylene chloride (first solvent) 402 parts by mass Methanol (second solvent) 60 parts by mass (Preparation of matting agent solution) 20 parts by mass of silica particles having an average particle diameter of 16 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) and 80 parts by mass of methanol were mixed well for 30 minutes to obtain a silica particle dispersion.
  • first solvent 402 parts by mass Methanol
  • matting agent solution 20 parts by mass of silica particles having an average particle diameter of 16 nm
  • AEROSIL R972 manufactured by Nippon Aerosil Co., Ltd.
  • This dispersion was charged into a disperser together with the following composition, and further stirred for 30 minutes or more to dissolve each component to prepare a matting agent solution.
  • Silica particle dispersion liquid having an average particle diameter of 16 nm 10.0 parts by mass Methylene chloride (first solvent) 76.3 parts by mass Methanol (second solvent) 3.4 parts by mass Cellulose acetate solution U 10.3 parts by mass (additive solution) Preparation)
  • first solvent 76.3 parts by mass Methylene chloride
  • second solvent 3.4 parts by mass Cellulose acetate solution
  • the following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.
  • optical anisotropy reducing agent 49.3 parts by mass
  • the following wavelength dispersion adjusting agent 4.9 parts by mass Methylene chloride (first solvent) 58.4 parts by mass Methanol (second solvent) 8.7 parts by mass Cellulose triacetate Solution U 12.8 parts by mass
  • the mass ratio of the compound that reduces optical anisotropy in the above composition and the wavelength dispersion adjusting agent to cellulose acetate was 12% and 1.2%, respectively.
  • the film was peeled from the band with a residual solvent amount of 30% and dried at 140 ° C. for 40 minutes to produce a long cellulose acetate film T0 having a thickness of 80 ⁇ m.
  • the in-plane retardation (Ro) of the obtained film was 1 nm (the slow axis was a direction perpendicular to the longitudinal direction of the film), and the retardation (Rt) in the thickness direction was ⁇ 1 nm.
  • the cellulose acetate film T0 saponified on one side of this polarizer and the commercially available cellulose triacetate film (Konica Minolta Tack KC4UY, manufactured by Konica Minolta Opto) on the other side were polyvinyl alcohol-based.
  • a polarizing plate P0 in which a cellulose triacetate film was bonded to a polarizer was prepared by continuously laminating using an adhesive and drying.
  • Example 4 ⁇ Production of liquid crystal display devices (L1) to (L4)> A liquid crystal cell was taken out from the liquid crystal television TH-32LX500 (manufactured by Matsushita Electric Industrial Co., Ltd.), and the polarizing plate and the optical film attached to the viewer side and the backlight side were peeled off. In this liquid crystal cell, when no voltage was applied and during black display, the liquid crystal molecules were aligned substantially in parallel between the glass substrates, and the slow axis direction was horizontal to the screen.
  • the produced polarizing plate (PL1 and P0) was cut so as to match the screen size, and an acrylic adhesive having a thickness of 20 ⁇ m was installed on the polarizing plate, It was bonded to the liquid crystal cell via an adhesive so as to have the configuration described later.
  • P0 is disposed on the polarizing plate on the backlight side
  • PL1 is disposed on the viewer side
  • the first optical anisotropic layer included in the polarizing plate PL1 is in contact with the glass substrate on the liquid crystal cell side.
  • the cellulose acetate film T0 contained in the polarizing plate P0 was bonded so as to be in contact with the glass substrate on the liquid crystal cell side.
  • the absorption axis of the polarizing plate PL1 and the slow axis of the liquid crystal cell were orthogonal to each other, and the absorption axes of the polarizing plate PL1 and the polarizing plate P0 were orthogonal to satisfy the constitution 1.
  • liquid crystal cell with the polarizing plate attached in this way was incorporated into the liquid crystal television TH-32LX500 again. In this way, a liquid crystal display device LCD-1 was produced.
  • the above polarizing plates PL1 were changed to polarizing plates PL2 to PL13, respectively, to prepare liquid crystal display devices LCD2 to LCD13.
  • liquid crystal display devices LCD2 to LCD4 the liquid crystal cell, the first optical anisotropic layer, the second optical anisotropic layer, and the polarizing plate layer are in this order, and the slow axis of the second optical anisotropic layer. And the major axis direction of the liquid crystal molecules during black display were substantially parallel.
  • Evaluation criteria ⁇ : 600 or more ⁇ : 500 or more ⁇ : less than 500 ⁇ and ⁇ are levels having no practical problem.
  • the liquid crystal display panel was subjected to forced deterioration (durability test) under conditions of 40 ° C. and 80%, and each liquid crystal display panel was treated for 500 hours.
  • the viewing angle was evaluated using the angle indicating the viewing angle of contrast 10 as an index.
  • the difference in viewing angle compared to the viewing angle where the liquid crystal display panel was not subjected to forced deterioration (endurance test) was defined as the contrast unevenness of the liquid crystal display device.
  • Evaluation criteria A: Contrast unevenness before and after forced deterioration is 5 ° or less with respect to all directions. ⁇ : There is a portion where the contrast unevenness before and after the forced deterioration is 5 ° or more and less than 10 ° with respect to the orientation, but there is no problem in practice. ⁇ : There is a portion where the unevenness of contrast before and after the forced deterioration is 10 ° or more and less than 15 ° with respect to some orientations, and the display image is uneven. X: Contrast unevenness before and after forced deterioration is 15 ° or more with respect to a part of the azimuth, and the image in black display is uneven.
  • Each polarizing plate was cut into a size of 5 cm ⁇ 7 cm.
  • the obtained cut pieces are temporarily adhered to the central part of each 6 cm ⁇ 8 cm glass plate with an acrylic adhesive having a thickness of 20 ⁇ m, and then pressed to be in an adhesive layer between the cut piece of the polarizing plate and the glass plate.
  • Each piece of the polarizing plate was bonded to a glass plate so as to completely remove the bubbles.
  • test pieces thus prepared were placed vertically in a constant temperature and humidity oven set at 80 ° C. and 95% RH so as not to overlap each other and fixed to the support frame for 1000 hours, and then the polarizer and the protective film were bonded to each piece. The sex was measured.
  • the film lifted portion is not found at all.
  • the film lifted portion is in the range of 1 to 5 mm in the periphery.
  • the film lifted portion is in the periphery of 5 mm or more.
  • the liquid crystal display device can realize high contrast, and at the same time, there is no problem of unevenness of contrast when a forced deterioration test is performed, and high display quality is provided. Further, by using a film having a moisture permeability within the moisture permeability range according to the present invention as a polarizing plate, a liquid crystal display device having excellent polarizer adhesion and stable against environmental fluctuations can be provided.
  • the front contrast is lowered and the display quality is lowered.
  • the first optically anisotropic layer and the second optically anisotropic layer are polarizing plates bonded with an adhesive, the environmental variation of each film unless the moisture permeability satisfies the moisture permeability range according to the present invention. Due to the difference in properties, contrast unevenness occurs depending on the location of the screen and the display quality deteriorates. Due to environmental changes, the adhesion between the polarizer and the second optically anisotropic layer is lowered, which adversely affects image display.
  • the present invention is excellent in satisfying the quality of all aspects of front contrast, contrast unevenness, and polarizer adhesion.

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Abstract

Disclosed is a polarizing plate which has durability with respect to changes of environmental conditions such as temperature and humidity, while exhibiting improved adhesion between a polarizer and a protective film.  Also disclosed is a liquid crystal display device, which uses the polarizing plate and has a wide viewing angle and improved front contrast unevenness. Specifically disclosed is a polarizing plate comprising at least a first optically anisotropic layer and a second optically anisotropic layer, wherein an adhesive layer, the first optically anisotropic layer, an adhesive layer, the second optically anisotropic layer and a polarizer are arranged in this order, while satisfying specific conditions.

Description

偏光板及びそれを用いた液晶表示装置Polarizing plate and liquid crystal display device using the same
　本発明は、偏光板及びそれを用いた液晶表示装置に関する。詳しくは、温度及び湿度等の環境条件変化に対し耐久性があり、偏光子と保護フィルムの間の密着性が向上した偏光板に関する。また、それを用いて正面コントラストムラを改善した広視野角の液晶表示装置に関する。 The present invention relates to a polarizing plate and a liquid crystal display device using the same. Specifically, the present invention relates to a polarizing plate that is durable against changes in environmental conditions such as temperature and humidity and has improved adhesion between a polarizer and a protective film. The present invention also relates to a wide viewing angle liquid crystal display device using the same to improve front contrast unevenness.
　液晶表示装置としては、視野角特性に優れた横電界を液晶に対して印加する、いわゆるインプレーンスイッチング（ＩＰＳ）モードによる液晶表示装置や、誘電率異方性が負の液晶を垂直配向してパネル内に形成した突起やスリット電極によって配向分割した垂直配向（ＶＡ）モードが提案され、実用化されている。 As a liquid crystal display device, a liquid crystal display device using a so-called in-plane switching (IPS) mode in which a lateral electric field excellent in viewing angle characteristics is applied to the liquid crystal, or a liquid crystal having a negative dielectric anisotropy is vertically aligned. A vertical alignment (VA) mode in which alignment is divided by protrusions and slit electrodes formed in the panel has been proposed and put into practical use.
　近年、これらのパネルはモニター用途に留まらず、ＴＶ用途として開発が進められており、それに伴って画面の輝度が大きく向上してきている。このため、これらの動作モードで従来問題とされていなっかった、黒表示時の対角位斜め入射方向での僅かな光漏れが表示品質の低下の原因として顕在化してきた。 In recent years, these panels have been developed not only for monitor applications but also for TV applications, and screen brightness has been greatly improved accordingly. For this reason, slight light leakage in the diagonally oblique incidence direction during black display, which has not been considered as a problem in these operation modes, has become apparent as a cause of deterioration in display quality.
　この色調や黒表示の視野角を改善する手段の提案された方式の多くは、液晶セル中の液晶の複屈折の異方性を、位相差フィルム等の光学補償シートを使用して視野角を改善する方式であるために、直交偏光板を斜めから見た場合の偏光軸交差角度の直交からのズレに基づく光漏れを十分に解決できないという問題がある。 Many of the proposed methods for improving the viewing angle of the color tone and the black display are based on the birefringence anisotropy of the liquid crystal in the liquid crystal cell by using an optical compensation sheet such as a retardation film. Since this is an improved system, there is a problem in that light leakage based on the deviation from the orthogonal crossing angle of the polarization axes when the orthogonal polarizing plate is viewed obliquely cannot be sufficiently solved.
　そこで特許文献１では、支持体上に光学補償シートに垂直配向してなる位相差層を光学異方性層として設け、さらにその層に添加剤を併用することにより視野角だけでなく、位相差ムラを原因とする画面のムラも改善する技術が提案されている。 Therefore, in Patent Document 1, a retardation layer formed by vertically aligning with an optical compensation sheet is provided on a support as an optically anisotropic layer, and by using an additive in the layer, not only a viewing angle but also a retardation is provided. Techniques have also been proposed for improving screen unevenness due to unevenness.
　特許文献２では、異方性層を設けるための支持体となるセルロースエステルフィルムの特性を規定した技術が提案されている。 Patent Document 2 proposes a technique that defines the characteristics of a cellulose ester film serving as a support for providing an anisotropic layer.
　しかしながら、これらの技術も光学異方性層を設けるための支持体の環境変化、特にバックライトによる熱及び保存雰囲気の湿度から受ける影響に対して発生する画面のムラには十分な対応といえず、さらに液晶表示装置の大画面化は、最終的に光学異方性層である液晶層の配向ムラを顕在化するという問題がある。 However, these techniques are not sufficient to cope with the environmental variations of the support for providing the optically anisotropic layer, especially the unevenness of the screen that occurs due to the influence of the heat from the backlight and the humidity of the storage atmosphere. Furthermore, the enlargement of the screen of the liquid crystal display device has a problem that the alignment unevenness of the liquid crystal layer, which is an optically anisotropic layer, finally becomes apparent.
特開２００７－４５９９３号公報JP 2007-45993 A 特開２００７－１５５９７２号公報JP 2007-155972 A
　本発明は、上記問題・状況に鑑みてなされたものであり、その解決課題は、温度及び湿度等の環境条件変化に対し耐久性があり、偏光子と保護フィルムの間の密着性が向上した偏光板を提供すること、及びそれを用いて正面コントラストムラを改善した広視野角の液晶表示装置を提供することである。 The present invention has been made in view of the above-mentioned problems and situations, and its solution is durable against changes in environmental conditions such as temperature and humidity, and improved adhesion between the polarizer and the protective film. It is to provide a polarizing plate, and to provide a liquid crystal display device having a wide viewing angle in which front contrast unevenness is improved using the polarizing plate.
　本発明者らは、上記課題を解決するために鋭意検討した結果、第１及び第２の光学異方性層を構成する光学フィルムそれぞれの、面内及び厚さ方向のリターデーション、及び透湿度を一定条件範囲内にコントロールすることが有効であることを見出し、本発明を完成するに至った。 As a result of intensive studies to solve the above problems, the present inventors have determined in-plane and thickness-direction retardation and moisture permeability of each of the optical films constituting the first and second optically anisotropic layers. The inventors have found that it is effective to control within a certain condition range, and have completed the present invention.
　すなわち、本発明に係る上記課題は、以下の手段により解決される。 That is, the above-mentioned problem according to the present invention is solved by the following means.
　１．少なくとも第１光学異方性層及び第２光学異方性層を有する偏光板であって、粘着層／第１光学異方性層／接着層／第２光学異方性層／偏光子の順で構成され、かつ下記要件（ｉ）～（iii）を満たすことを特徴とする偏光板。
（ｉ）第１光学異方性層が、アクリル樹脂含有フィルムであって、面内のリターデーションＲｏ（１）が－４０～２０ｎｍの範囲内であり、かつ、厚さ方向のリターデーションＲｔ（１）が－４００～－８０ｎｍの範囲内である。
（ii）第２光学異方性層が、セルロースエステル樹脂で構成されたフィルムであって、屈折率がｎｘ＞ｎｙ＞ｎｚの関係にあり、面内のリターデーションＲｏ（２）が２０～１５０ｎｍの範囲内であり、かつ、厚さ方向のリターデーションＲｔ（２）が１００～３００ｎｍの範囲内である。
（iii）第１光学異方性層を構成するフィルムの透湿度が２０～６００ｇ／ｍ２・２４ｈの範囲内であり、第２光学異方性層を構成するフィルムの透湿度が６００～１５００ｇ／ｍ２・２４ｈである。
〔但し、第１光学異方性層及び第２光学異方性層の屈折率は、以下のｎｘ、ｎｙ、ｎｚで定義され、
Ｒｏ（１）＝（ｎｘ－ｎｙ）×ｄ
Ｒｔ（１）＝（（ｎｘ＋ｎｙ）／２－ｎｚ）×ｄ、
及び
Ｒｏ（２）＝（ｎｘ－ｎｙ）×ｄ
Ｒｔ（２）＝（（ｎｘ＋ｎｙ）／２－ｎｚ）×ｄ
で示される。
（式中、ｎｘは光学異方性層の面内の幅手方向の屈折率を、ｎｙは光学異方性層の面内で製膜又は搬送方向でありｎｘと面内で直交する方向の屈折率を、ｎｚは光学異方性層の厚さ方向の屈折率を、ｄは光学異方性層の厚さ（ｎｍ）をそれぞれ表す。屈折率の測定波長は５９０ｎｍである。）〕
　２．前記第１項に記載の偏光板を用いたことを特徴とする液晶表示装置。 1. A polarizing plate having at least a first optical anisotropic layer and a second optical anisotropic layer, in the order of adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic layer / polarizer And a polarizing plate characterized by satisfying the following requirements (i) to (iii):
(I) The first optically anisotropic layer is an acrylic resin-containing film, the in-plane retardation Ro (1) is in the range of −40 to 20 nm, and the thickness direction retardation Rt ( 1) is in the range of −400 to −80 nm.
(Ii) The second optically anisotropic layer is a film composed of a cellulose ester resin and has a refractive index of nx>ny> nz, and an in-plane retardation Ro (2) of 20 to 150 nm. And retardation Rt (2) in the thickness direction is in the range of 100 to 300 nm.
(Iii) The moisture permeability of the film constituting the first optical anisotropic layer is in the range of 20 to 600 g / m 2 · 24 h, and the moisture permeability of the film constituting the second optical anisotropic layer is 600 to 1500 g. / M 2 · 24h.
[However, the refractive indexes of the first optical anisotropic layer and the second optical anisotropic layer are defined by the following nx, ny, and nz,
Ro (1) = (nx−ny) × d
Rt (1) = ((nx + ny) / 2−nz) × d,
And Ro (2) = (nx−ny) × d
Rt (2) = ((nx + ny) / 2−nz) × d
Indicated by
(Where nx is the refractive index in the width direction in the plane of the optically anisotropic layer, ny is the film forming or conveying direction in the plane of the optically anisotropic layer, and is in the direction perpendicular to nx in the plane) The refractive index, nz represents the refractive index in the thickness direction of the optically anisotropic layer, d represents the thickness (nm) of the optically anisotropic layer, and the measurement wavelength of the refractive index is 590 nm.)]
2. A liquid crystal display device using the polarizing plate described in the above item 1.
　本発明の上記手段により、温度及び湿度等の環境条件変化に対し耐久性があり、偏光子と保護フィルムの間の密着性が向上した偏光板を提供することができる。また、それを用いて正面コントラストムラを改善した広視野角の液晶表示装置を提供することができる。 By the above means of the present invention, it is possible to provide a polarizing plate that is durable against changes in environmental conditions such as temperature and humidity and has improved adhesion between the polarizer and the protective film. Further, it is possible to provide a liquid crystal display device having a wide viewing angle with improved front contrast unevenness.
本発明に用いられる溶液流延製膜方法のドープ調製工程、流延工程及び乾燥工程を模式的に示した図The figure which showed typically the dope preparation process, casting process, and drying process of the solution casting film forming method used for this invention. 偏光板と液晶表示装置の構成１を模式的に示した図The figure which showed typically the structure 1 of a polarizing plate and a liquid crystal display device 偏光板と液晶表示装置の構成２を模式的に示した図The figure which showed typically the structure 2 of a polarizing plate and a liquid crystal display device
　本発明の偏光板は、少なくとも第１光学異方性層及び第２光学異方性層を有する偏光板であって、粘着層／第１光学異方性層／接着層／第２光学異方性層／偏光子の順で構成され、かつ前記要件（ｉ）～（iii）を満たすことを特徴とする。この特徴は、請求項１及び請求項２に係る発明に共通する技術的特徴である。 The polarizing plate of the present invention is a polarizing plate having at least a first optical anisotropic layer and a second optical anisotropic layer, and is an adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic. It is characterized in that it is configured in the order of a functional layer / polarizer and satisfies the requirements (i) to (iii). This feature is a technical feature common to the inventions according to claims 1 and 2.
　以下、本発明とその構成要素、及び本発明を実施するための最良の形態・態様について詳細な説明をする。 Hereinafter, the present invention, its components, and the best mode and mode for carrying out the present invention will be described in detail.
　（第２光学異方性層）
　本発明に係る第２光学異方性層は、セルロースエステル樹脂で構成されたフィルムであって、屈折率がｎｘ＞ｎｙ＞ｎｚの関係にあり、面内のリターデーションＲｏ（１）が２０～１５０ｎｍの範囲内であり、かつ、厚さ方向のリターデーションＲｔ（１）が１００～３００ｎｍの範囲内であることを特徴とする。 (Second optically anisotropic layer)
The second optically anisotropic layer according to the present invention is a film composed of a cellulose ester resin and has a refractive index of nx>ny> nz, and an in-plane retardation Ro (1) of 20 to The retardation Rt (1) in the thickness direction is within the range of 150 nm and the thickness direction retardation Rt (1) is within the range of 100 to 300 nm.
　また、当該第２光学異方性層を構成するフィルムの透湿度は、６０℃、９５％ＲＨにおいて、６００～１５００ｇ／ｍ２・２４ｈの範囲内であることを特徴とする。 The film constituting the second optically anisotropic layer has a moisture permeability of 600 to 1500 g / m 2 · 24 h at 60 ° C. and 95% RH.
　本発明においては、上記特徴を実現するために第２光学異方性層を下記の要件等を満たすセルロースエステルフィルムを用いて構成することが好ましい。 In the present invention, in order to realize the above characteristics, it is preferable to configure the second optically anisotropic layer using a cellulose ester film that satisfies the following requirements.
　＜第２光学異方性層に用いるセルロースエステル樹脂＞
　本発明では、第２光学異方性層として、特定のセルロースエステル樹脂から実質的になるセルロースエステルフィルムを用いる。 <Cellulose ester resin used for the second optically anisotropic layer>
In the present invention, a cellulose ester film substantially made of a specific cellulose ester resin is used as the second optically anisotropic layer.
　第２光学異方性層としてのリターデーションの範囲を満たすために、アセチル置換セルロースである、ジアセチルセルロース（置換度２）とトリアセチルセルロース（置換度３）の置換度（２～３）の間で選択された、セルロースエステル樹脂に後述のリターデーション上昇剤を添加剤として用いることができる。 In order to satisfy the retardation range as the second optically anisotropic layer, between the substitution degree (2 to 3) of diacetyl cellulose (substitution degree 2) and triacetyl cellulose (substitution degree 3), which are acetyl-substituted celluloses The retardation increasing agent described later can be used as an additive for the cellulose ester resin selected in (1).
　一方、アセチル基に加えて、アセチル基以外の置換基をもつセルロースエスエル樹脂で構成させるフィルムを用いることもできる。 On the other hand, in addition to the acetyl group, a film composed of cellulose sell resin having a substituent other than the acetyl group may be used.
　前記セルロースエステルは、セルロースのヒドロキシル基（水酸基）をアセチル基及び炭素原子数が３以上で、かつ好ましくは５以下のアシル基で置換して得られたセルロースの混合脂肪酸エステルであって、セルロースのヒドロキシル基（水酸基）への置換度が、下記数式（Ｉ）及び（II）を満たすセルロースエステルであることが好ましい。
数式（Ｉ）：２．０≦Ａ＋Ｂ≦３．０
数式（II）：０＜Ｂ
　ここで、式中、Ａ及びＢはセルロースのヒドロキシル基（水酸基）に置換されているアシル基の置換度を表し、Ａはアセチル基の置換度、Ｂは炭素原子数３以上５以下のアシル基の置換度である。 The cellulose ester is a mixed fatty acid ester of cellulose obtained by substituting the hydroxyl group (hydroxyl group) of cellulose with an acetyl group and an acyl group having 3 or more carbon atoms, and preferably 5 or less carbon atoms, The degree of substitution with a hydroxyl group (hydroxyl group) is preferably a cellulose ester satisfying the following mathematical formulas (I) and (II).
Formula (I): 2.0 ≦ A + B ≦ 3.0
Formula (II): 0 <B
Here, in the formula, A and B represent the substitution degree of the acyl group substituted by the hydroxyl group (hydroxyl group) of cellulose, A is the substitution degree of the acetyl group, and B is the acyl group having 3 to 5 carbon atoms. Is the degree of substitution.
　上記式を満足する限り、異なる２種類以上のセルロースエステルを混合して用いてもよい。 As long as the above formula is satisfied, two or more different cellulose esters may be mixed and used.
　セルロースを構成するβ－１，４結合しているグルコース単位は、２位、３位及び６位に遊離のヒドロキシル基（水酸基）を有している。 The β-1,4-bonded glucose unit constituting cellulose has free hydroxyl groups (hydroxyl groups) at the 2nd, 3rd and 6th positions.
　セルロースエステルは、これらのヒドロキシル基（水酸基）の一部又は全部をアシル基によりエステル化した重合体（ポリマー）である。アシル置換度は、２位、３位及び６位のそれぞれについて、セルロースがエステル化している割合（１００％のエステル化は置換度１）を意味する。 Cellulose ester is a polymer obtained by esterifying some or all of these hydroxyl groups (hydroxyl groups) with acyl groups. The degree of acyl substitution means the proportion of cellulose esterified at each of the 2-position, 3-position and 6-position (100% esterification has a degree of substitution of 1).
　本発明では、環境湿度の影響の観点から、ヒドロキシル基（水酸基）のＡとＢとの置換度の総和（Ａ＋Ｂ）は、上記式（Ｉ）に示すように、２．０～３．０であり、好ましくは２．２～２．９であり、特に好ましくは２．４０～２．８５である。また、Ｂの置換度は上記式（II）に示すように、０を越える値であり、好ましくは０．９以上であり、特に好ましくは１．３以上である。 In the present invention, from the viewpoint of the influence of environmental humidity, the sum (A + B) of the substitution degree of A and B of the hydroxyl group (hydroxyl group) is 2.0 to 3.0 as shown in the above formula (I). Yes, preferably 2.2 to 2.9, particularly preferably 2.40 to 2.85. Further, the substitution degree of B is a value exceeding 0, preferably 0.9 or more, particularly preferably 1.3 or more, as shown in the above formula (II).
　さらに、Ｂはその２８％以上が６位ヒドロキシル基（水酸基）の置換度であるのが好ましいが、より好ましくは３０％以上が６位ヒドロキシル基（水酸基）の置換度であり、３１％以上がさらに好ましく、特に３２％以上が６位ヒドロキシル基（水酸基）の置換度であることが好ましい。 Further, 28% or more of B is preferably the substitution degree of the 6-position hydroxyl group (hydroxyl group), more preferably 30% or more is the substitution degree of the 6-position hydroxyl group (hydroxyl group), and 31% or more is the substitution degree. More preferably, 32% or more is preferably the substitution degree of the 6-position hydroxyl group (hydroxyl group).
　また、さらに、セルロースエステルの６位ヒドロキシル基（水酸基）のＡとＢの置換度の総和が０．７５以上であるのが好ましく、さらには０．８０以上が、特には０．８５以上が好ましい。 Furthermore, the sum of the substitution degrees of A and B in the 6-position hydroxyl group (hydroxyl group) of the cellulose ester is preferably 0.75 or more, more preferably 0.80 or more, and particularly preferably 0.85 or more. .
　これらのセルロースエステルフィルムにより溶解性、濾過性の好ましいフィルム調製用の溶液が作製でき、非塩素系有機溶媒においても、良好な溶液の作製が可能となる。さらに粘度が低く濾過性のよい溶液の調製が可能となる。 These cellulose ester films can produce a solution for preparing a film having preferable solubility and filterability, and a good solution can be produced even in a non-chlorine organic solvent. Furthermore, it is possible to prepare a solution having a low viscosity and good filterability.
　上記炭素原子数３以上５以下のアシル基としては、脂肪族基でも芳香族炭化水素基でもよく特に限定されない。 The acyl group having 3 to 5 carbon atoms may be an aliphatic group or an aromatic hydrocarbon group and is not particularly limited.
　それらは、例えばセルロースのアルキルカルボニルエステル、アルケニルカルボニルエステルあるいは芳香族カルボニルエステル、芳香族アルキルカルボニルエステルなどであり、それぞれさらに置換された基を有していてもよい。 These are, for example, cellulose alkylcarbonyl esters, alkenylcarbonyl esters, aromatic carbonyl esters, aromatic alkylcarbonyl esters, and the like, each of which may have a further substituted group.
　これらの好ましいＢとしては、プロピオニル、ブタノイル、ペンタノイル、ヘキサノイル、オクタノイル、デカノイル、ドデカノイル、トリデカノイル、テトラデカノイル、ヘキサデカノイル、オクタデカノイル、ｉ－ブタノイル、ｔ－ブタノイル、シクロヘキサンカルボニル、オレオイル、ベンゾイル、ナフチルカルボニル、シンナモイル基などを挙げることができる。 These preferred B include propionyl, butanoyl, pentanoyl, hexanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl, tetradecanoyl, hexadecanoyl, octadecanoyl, i-butanoyl, t-butanoyl, cyclohexanecarbonyl, oleoyl, benzoyl , Naphthylcarbonyl, cinnamoyl group and the like.
　これらの中でも、好ましくはプロピオニル、ブタノイル、ドデカノイル、オクタデカノイル、ｔ－ブタノイル、オレオイル、ベンゾイル、ナフチルカルボニル、シンナモイル基などである。特に好ましくはプロピオニル、ブタノイル基である。 Among these, propionyl, butanoyl, dodecanoyl, octadecanoyl, t-butanoyl, oleoyl, benzoyl, naphthylcarbonyl, cinnamoyl group and the like are preferable. Particularly preferred are propionyl and butanoyl groups.
　また、置換度Ｂは、０．３以上であることが好ましく、０．４～２．０以下がより好ましく、０．５～１．５がさらに好ましく、０．６～１．３が特に好ましい。 The degree of substitution B is preferably 0.3 or more, more preferably 0.4 to 2.0 or less, further preferably 0.5 to 1.5, and particularly preferably 0.6 to 1.3. .
　置換度Ｂをこの範囲とすることで、高温保存時のＴｇ低下に伴う物理変形と、高湿保存時の光学特性変化を抑制できる。 By setting the substitution degree B within this range, it is possible to suppress physical deformation accompanying a decrease in Tg during high temperature storage and changes in optical properties during high humidity storage.
　本発明に使用するセルロースエステルとしては、具体的には、セルロースアセテートプロピオネート、セルロースアセテートブチレートが挙げられる。 Specific examples of the cellulose ester used in the present invention include cellulose acetate propionate and cellulose acetate butyrate.
　アセチル基、プロピオニル基及び／又はブチル基の置換度はＡＳＴＭ：Ｄ－８１７－９６（セルロースアセテート等の試験方法）に従い測定し、計算で求めることができる。 The degree of substitution of the acetyl group, propionyl group and / or butyl group can be determined by measurement according to ASTM: D-817-96 (test method for cellulose acetate etc.) and calculation.
　（セルロースエステルの合成方法）
　セルロースエステルの合成方法の基本的な原理は、右田他、木材化学１８０～１９０頁（共立出版、１９６８年）に記載されている。代表的な合成方法は、カルボン酸無水物－酢酸－硫酸触媒による液相酢化法である。 (Synthesis method of cellulose ester)
The basic principle of the cellulose ester synthesis method is described in Mita et al., Wood chemistry, pages 180-190 (Kyoritsu Shuppan, 1968). A typical synthesis method is a liquid phase acetylation method using a carboxylic acid anhydride-acetic acid-sulfuric acid catalyst.
　前記セルロースエステルを得るには、具体的には、綿花リンタや木材パルプ等のセルロース原料を適当量の酢酸で前処理した後、予め冷却したカルボン酸化混液に投入してエステル化し、完全セルロースエステル（２位、３位及び６位のアシル置換度の合計が、ほぼ３．００）を合成する。 In order to obtain the cellulose ester, specifically, a cellulose raw material such as cotton linter or wood pulp is pretreated with an appropriate amount of acetic acid, and is then esterified by introducing it into a pre-cooled carboxylated mixed solution. The total degree of acyl substitution at the 2nd, 3rd and 6th positions is approximately 3.00).
　上記カルボン酸化混液は、一般に溶媒としての酢酸、エステル化剤としての無水カルボン酸及び触媒としての硫酸を含む。無水カルボン酸は、これと反応するセルロース及び系内に存在する水分の合計よりも、化学量論的に過剰量で使用することが普通である。 The carboxylated mixed solution generally contains acetic acid as a solvent, carboxylic anhydride as an esterifying agent, and sulfuric acid as a catalyst. The carboxylic anhydride is usually used in a stoichiometric excess over the sum of the cellulose that reacts with it and the water present in the system.
　エステル化反応終了後に、系内に残存している過剰の無水カルボン酸の加水分解及びエステル化触媒の一部の中和のために、中和剤（例えば、カルシウム、マグネシウム、鉄、アルミニウム又は亜鉛の炭酸塩、酢酸塩又は酸化物）の水溶液を添加する。 After completion of the esterification reaction, a neutralizing agent (for example, calcium, magnesium, iron, aluminum or zinc) is used for hydrolysis of excess carboxylic anhydride remaining in the system and neutralization of a part of the esterification catalyst. Of carbonate, acetate or oxide).
　次に、得られた完全セルロースエステルを少量の酢化反応触媒（一般には、残存する硫酸）の存在下で、５０～９０℃に保つことによりケン化熟成し、所望のアシル置換度及び重合度を有するセルロースエステルまで変化させる。所望のセルロースエステルが得られた時点で、系内に残存している触媒を前記のような中和剤を用いて完全に中和するか、あるいは中和することなく水又は希硫酸中にセルロースエステル溶液を投入（あるいは、セルロースエステル溶液中に、水又は希硫酸を投入）してセルロースエステルを分離し、洗浄及び安定化処理を行う等して、前記の特定のセルロースエステルを得ることができる。 Next, the obtained complete cellulose ester is saponified and aged by maintaining it at 50 to 90 ° C. in the presence of a small amount of an acetylation reaction catalyst (generally, remaining sulfuric acid) to obtain a desired degree of acyl substitution and degree of polymerization. To a cellulose ester having When the desired cellulose ester is obtained, the catalyst remaining in the system is completely neutralized using the neutralizing agent as described above, or the cellulose in water or dilute sulfuric acid without neutralization. The specific cellulose ester can be obtained by introducing an ester solution (or by adding water or dilute sulfuric acid into the cellulose ester solution) to separate the cellulose ester, and performing washing and stabilization treatment. .
　前記セルロースエステルフィルムは、フィルムを構成するポリマー成分が実質的に上記の特定のセルロースエステルからなることが好ましい。『実質的に』とは、ポリマー成分の５５質量％以上（好ましくは７０質量％以上、さらに好ましくは８０質量％以上）を意味する。 In the cellulose ester film, the polymer component constituting the film is preferably substantially composed of the specific cellulose ester described above. “Substantially” means 55% by mass or more (preferably 70% by mass or more, more preferably 80% by mass or more) of the polymer component.
　前記セルロースエステルは、粒子状で使用することが好ましい。使用する粒子の９０質量％以上は、０．５～５ｍｍの粒子径を有することが好ましい。また、使用する粒子の５０質量％以上が１～４ｍｍの粒子径を有することが好ましい。セルロースエステル粒子は、なるべく球形に近い形状を有することが好ましい。 The cellulose ester is preferably used in the form of particles. 90% by mass or more of the particles used preferably have a particle size of 0.5 to 5 mm. Further, it is preferable that 50% by mass or more of the particles to be used have a particle diameter of 1 to 4 mm. The cellulose ester particles preferably have a shape as close to a sphere as possible.
　本発明で好ましく用いられるセルロースエステルの重合度は、粘度平均重合度で、好ましくは２００～７００、より好ましくは２５０～５５０、さらに好ましくは２５０～４００であり、特に好ましくは２５０～３５０である。平均重合度は、宇田らの極限粘度法（宇田和夫、斉藤秀夫、「繊維学会誌」、１９６２年、第１８巻第１号、１０５～１２０頁）により測定できる。さらに特開平９－９５５３８号公報に詳細に記載されている。 The polymerization degree of the cellulose ester preferably used in the present invention is a viscosity average polymerization degree, preferably 200 to 700, more preferably 250 to 550, still more preferably 250 to 400, and particularly preferably 250 to 350. The average degree of polymerization can be measured by the intrinsic viscosity method of Uda et al. (Kazuo Uda, Hideo Saito, “Journal of Textile Society”, 1962, Vol. 18, No. 1, pp. 105-120). Further details are described in JP-A-9-95538.
　低分子成分が除去されると、平均分子量（重合度）が高くなるが、粘度は通常のセルロースエステルよりも低くなるため、前記セルロースエステルとしては低分子成分を除去したものが有用である。 When the low molecular component is removed, the average molecular weight (degree of polymerization) is increased, but the viscosity is lower than that of a normal cellulose ester. Therefore, the cellulose ester from which the low molecular component is removed is useful.
　低分子成分の少ないセルロースエステルは、通常の方法で合成したセルロースエステルから低分子成分を除去することにより得ることができる。低分子成分の除去は、セルロースエステルを適当な有機溶媒で洗浄することにより実施できる。 A cellulose ester having a small amount of low molecular components can be obtained by removing low molecular components from a cellulose ester synthesized by an ordinary method. The removal of low molecular components can be carried out by washing the cellulose ester with a suitable organic solvent.
　なお、低分子成分の少ないセルロースエステルを製造する場合、酢化反応における硫酸触媒量を、セルロースエステル１００質量部に対して０．５～２５質量部に調整することが好ましい。 In the case of producing a cellulose ester having a small amount of low molecular components, it is preferable to adjust the amount of sulfuric acid catalyst in the acetylation reaction to 0.5 to 25 parts by mass with respect to 100 parts by mass of the cellulose ester.
　硫酸触媒の量を上記範囲にすると、分子量分布の点でも好ましい（分子量分布の均一な）セルロースエステルを合成することができる。セルロースエステルの製造時に使用される際には、その含水率は２質量％以下であることが好ましく、さらに好ましくは１質量％以下であり、特には０．７質量％以下である。 When the amount of the sulfuric acid catalyst is within the above range, a cellulose ester that is preferable in terms of molecular weight distribution (uniform molecular weight distribution) can be synthesized. When used during the production of cellulose ester, the water content is preferably 2% by mass or less, more preferably 1% by mass or less, and particularly 0.7% by mass or less.
　一般に、セルロースエステルは、水を含有しており含水率２．５～５質量％が知られている。セルロースエステルの含水率を上記範囲にするためには、乾燥することが必要であり、その方法については特に限定されない。 Generally, cellulose ester contains water and is known to have a water content of 2.5 to 5% by mass. In order to make the moisture content of a cellulose ester into the said range, it is necessary to dry, The method is not specifically limited.
　前記セルロースエステルの原料綿や合成方法は、発明協会公開技報公技番号２００１－１７４５号（２００１年３月１５日発行、発明協会）ｐ．７－１２に詳細に記載されている原料綿や合成方法を採用できる。 The raw material cotton of cellulose ester and the synthesis method thereof are disclosed in JIII Journal of Technical Disclosure No. 2001-1745 (issued March 15, 2001, Invention Association) p. Raw material cotton and synthetic methods described in detail in 7-12 can be employed.
　本発明に係るセルロースエステルフィルムは、前記の特定のセルロースエステルと必要に応じて添加剤とを有機溶媒に溶解させたセルロースエステル溶液を調製し、該溶液を用いてフィルム化することにより得ることができる。 The cellulose ester film according to the present invention can be obtained by preparing a cellulose ester solution in which the specific cellulose ester and, if necessary, an additive are dissolved in an organic solvent, and forming the film using the solution. it can.
　（第２光学異方性層のその他の添加剤）
　前記セルロースエステル溶液に添加可能な添加剤としては、例えば、可塑剤、紫外線吸収剤、劣化防止剤、リターデーション（光学異方性）上昇剤、リターデーション（光学異方性）減少剤、波長分散調整剤、微粒子、染料、剥離促進剤、赤外吸収剤などを挙げることができる。 (Other additives for the second optically anisotropic layer)
Additives that can be added to the cellulose ester solution include, for example, plasticizers, ultraviolet absorbers, deterioration inhibitors, retardation (optical anisotropy) increasing agents, retardation (optical anisotropy) reducing agents, and wavelength dispersion. Examples thereof include regulators, fine particles, dyes, peeling accelerators and infrared absorbers.
　本発明においては、リターデーション上昇剤を用いる。また、可塑剤、紫外線吸収剤、染料及び剥離促進剤の少なくとも１種以上を用いるのが好ましい。 In the present invention, a retardation increasing agent is used. Moreover, it is preferable to use at least one of a plasticizer, an ultraviolet absorber, a dye and a peeling accelerator.
　それらは固体でもよく油状物でもよい。すなわち、その融点や沸点において特に限定されるものではない。例えば２０℃以下と２０℃以上の紫外線吸収剤を混合して用いたり、同様に可塑剤を混合して用いることができ、例えば特開２００１－１５１９０１号公報などに記載されている。 They may be solid or oily. That is, the melting point and boiling point are not particularly limited. For example, UV absorbers of 20 ° C. or lower and 20 ° C. or higher can be mixed and used, and plasticizers can also be mixed and used, for example, as described in JP-A-2001-151901.
　〈紫外線吸収剤〉
　紫外線吸収剤としては、目的に応じ任意の種類のものを選択することができ、サリチル酸エステル系、ベンゾフェノン系、ベンゾトリアゾール系、ベンゾエート系、シアノアクリレート系、ニッケル錯塩系等の吸収剤を用いることができ、好ましくはベンゾフェノン系、ベンゾトリアゾール系、サリチル酸エステル系である。 <Ultraviolet absorber>
As the ultraviolet absorber, any type can be selected according to the purpose, and a salicylic acid ester-based, benzophenone-based, benzotriazole-based, benzoate-based, cyanoacrylate-based, nickel complex-based absorber or the like is used. Preferred are benzophenone series, benzotriazole series, and salicylic acid ester series.
　ベンゾフェノン系紫外線吸収剤の例として、２，４－ジヒドロキシベンゾフェノン、２－ヒドロキシ－４－アセトキシベンゾフェノン、２－ヒドロキシ－４－メトキシベンゾフェノン、２，２’－ジ－ヒドロキシ－４－メトキシベンゾフェノン、２，２’－ジ－ヒドロキシ－４，４’－メトキシベンゾフェノン、２－ヒドロキシ－４－ｎ－オクトキシベンゾフェノン、２－ヒドロキシ－４－ドデシルオキシベンゾフェノン、２－ヒドロキシ－４－（２－ヒドロキシ－３－メタクリロキシ）プロポキシベンゾフェノン等を挙げることができる。 Examples of benzophenone ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-acetoxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2′-di-hydroxy-4-methoxybenzophenone, 2, 2′-di-hydroxy-4,4′-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2-hydroxy-4- (2-hydroxy-3- And methacryloxy) propoxybenzophenone.
　ベンゾトリアゾール系紫外線吸収剤としては、２（２’－ヒドロキシ－３’－ｔｅｒｔ－ブチル－５’－メチルフェニル）－５－クロルベンゾトリアゾール、２（２’－ヒドロキシ－５’－ｔｅｒｔ－ブチルフェニル）ベンゾトリアゾール、２（２’－ヒドロキシ－３’，５’－ジ－ｔｅｒｔ－アミルフェニル）ベンゾトリアゾール、２（２’－ヒドロキシ－３’，５’－ジ－ｔｅｒｔ－ブチルフェニル）－５－クロルベンゾトリアゾール、２（２’－ヒドロキシ－５’－ｔｅｒｔ－オクチルフェニル）ベンゾトリアゾール等を挙げることができる。 As a benzotriazole ultraviolet absorber, 2 (2′-hydroxy-3′-tert-butyl-5′-methylphenyl) -5-chlorobenzotriazole, 2 (2′-hydroxy-5′-tert-butylphenyl) ) Benzotriazole, 2 (2′-hydroxy-3 ′, 5′-di-tert-amylphenyl) benzotriazole, 2 (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5 And chlorobenzotriazole, 2 (2′-hydroxy-5′-tert-octylphenyl) benzotriazole, and the like.
　サリチル酸エステル系としては、フェニルサリシレート、ｐ－オクチルフェニルサリシレート、ｐ－ｔｅｒｔ－ブチルフェニルサリシレート等を挙げることができる。 Examples of the salicylic acid ester group include phenyl salicylate, p-octylphenyl salicylate, p-tert-butylphenyl salicylate, and the like.
　これら例示した紫外線吸収剤の中でも、特に２－ヒドロキシ－４－メトキシベンゾフェノン、２，２’－ジ－ヒドロキシ－４，４’－メトキシベンゾフェノン、２（２’－ヒドロキシ－３’－ｔｅｒｔ－ブチル－５’－メチルフェニル）－５－クロルベンゾトリアゾール、２（２’－ヒドロキシ－５’－ｔｅｒｔ－ブチルフェニル）ベンゾトリアゾール、２（２’－ヒドロキシ－３’，５’－ジ－ｔｅｒｔ－アミルフェニル）ベンゾトリアゾール、２（２’－ヒドロキシ－３’，５’－ジ－ｔｅｒｔ－ブチルフェニル）－５－クロルベンゾトリアゾールが特に好ましい。 Among these exemplified UV absorbers, in particular, 2-hydroxy-4-methoxybenzophenone, 2,2′-di-hydroxy-4,4′-methoxybenzophenone, 2 (2′-hydroxy-3′-tert-butyl- 5'-methylphenyl) -5-chlorobenzotriazole, 2 (2'-hydroxy-5'-tert-butylphenyl) benzotriazole, 2 (2'-hydroxy-3 ', 5'-di-tert-amylphenyl) ) Benzotriazole, 2 (2′-hydroxy-3 ′, 5′-di-tert-butylphenyl) -5-chlorobenzotriazole is particularly preferred.
　紫外線吸収剤は、吸収波長の異なる複数の吸収剤を複合して用いることが、広い波長範囲で高い遮断効果を得ることができるので好ましい。液晶用紫外線吸収剤は、液晶の劣化防止の観点から、波長３７０ｎｍ以下の紫外線の吸収能に優れ、且つ、液晶表示性の観点から、波長４００ｎｍ以上の可視光の吸収が少ないものが好ましい。 As the ultraviolet absorber, it is preferable to use a combination of a plurality of absorbers having different absorption wavelengths because a high blocking effect can be obtained in a wide wavelength range. The ultraviolet absorbent for liquid crystal is preferably one that is excellent in the ability to absorb ultraviolet light having a wavelength of 370 nm or less from the viewpoint of preventing deterioration of the liquid crystal and that has little absorption of visible light having a wavelength of 400 nm or more from the viewpoint of liquid crystal display properties.
　特に好ましい紫外線吸収剤は、先に上げたベンゾトリアゾール系化合物やベンゾフェノン系化合物、サリチル酸エステル系化合物である。中でも、ベンゾトリアゾール系化合物は、セルロースエステルに対する不要な着色が少ないことから好ましい。 Particularly preferred ultraviolet absorbers are the benzotriazole compounds, benzophenone compounds and salicylic acid ester compounds mentioned above. Among these, a benzotriazole-based compound is preferable because unnecessary coloring with respect to the cellulose ester is small.
　また、紫外線吸収剤については、特開昭６０－２３５８５２号、特開平３－１９９２０１号、同５－１９４７８９号、同５－２７１４７１号、同６－１０７８５４号、同６－１１８２３３号、同６－１３０２２６号、同６－１４８４３０号、同７－１１０５５号、同７－１１０５６号、同８－２９６１９号、同８－２３９５０９号、特開２０００－２０４１７３号の各公報に記載の化合物も用いることができる。 As for ultraviolet absorbers, JP-A-60-235852, JP-A-3-199201, JP-A-5-194789, JP-A-5-271471, JP-A-6-107854, JP-A-6-118233, JP-A-6- The compounds described in JP-A Nos. 130226, 6-148430, 7-11055, 7-11056, 8-29619, 8-239509, and JP-A-2000-204173 can also be used. it can.
　紫外線吸収剤の添加量は、セルロースエステルに対し０．００１～５質量％が好ましく、０．０１～１質量％がより好ましい。添加量が０．００１質量％未満では添加効果を十分に発揮することができず、添加量が５質量％を超えると、フィルム表面へ紫外線吸収剤がブリードアウトする場合がある。 The addition amount of the ultraviolet absorber is preferably 0.001 to 5% by mass, more preferably 0.01 to 1% by mass with respect to the cellulose ester. If the addition amount is less than 0.001% by mass, the effect of addition cannot be sufficiently exhibited. If the addition amount exceeds 5% by mass, the ultraviolet absorber may bleed out to the film surface.
　また、紫外線吸収剤はセルロースエステル溶解時に同時に添加してもよいし、溶解後のドープに添加してもよい。特にスタティックミキサ等を用い、流延直前にドープに紫外線吸収剤溶液を添加する形態が、分光吸収特性を容易に調整することができ、好ましい。 Further, the ultraviolet absorber may be added simultaneously with the dissolution of the cellulose ester, or may be added to the dope after dissolution. In particular, a mode in which an ultraviolet absorbent solution is added to the dope immediately before casting using a static mixer or the like is preferable because the spectral absorption characteristics can be easily adjusted.
　〈劣化防止剤〉
　前記劣化防止剤は、セルローストリアセテート等が劣化、分解するのを防止することができる。劣化防止剤としては、ブチルアミン、ヒンダードアミン化合物（特開平８－３２５５３７号公報）、グアニジン化合物（特開平５－２７１４７１号公報）、ベンゾトリアゾール系ＵＶ吸収剤（特開平６－２３５８１９号公報）、ベンゾフェノン系ＵＶ吸収剤（特開平６－１１８２３３号公報）などの化合物がある。 <Deterioration inhibitor>
The deterioration inhibitor can prevent cellulose triacetate and the like from deteriorating and decomposing. Examples of deterioration inhibitors include butylamine, hindered amine compounds (Japanese Patent Laid-Open No. 8-325537), guanidine compounds (Japanese Patent Laid-Open No. 5-271471), benzotriazole-based UV absorbers (Japanese Patent Laid-Open No. 6-235819), and benzophenone-based compounds. There are compounds such as UV absorbers (JP-A-6-118233).
　〈可塑剤〉
　可塑剤としては、リン酸エステル、カルボン酸エステルであることが好ましい。また、前記可塑剤が、トリフェニルフォスフェート（ＴＰＰ）、トリクレジルホスフェート（ＴＣＰ）、クレジルジフェニルホスフェート、オクチルジフェニルホスフェート、ビフェニルジフェニルホスフェート（ＢＤＰ）、トリオクチルホスフェート、トリブチルホスフェート、ジメチルフタレート（ＤＭＰ）、ジエチルフタレート（ＤＥＰ）、ジブチルフタレート（ＤＢＰ）、ジオクチルフタレート（ＤＯＰ）、ジフェニルフタレート（ＤＰＰ）、ジエチルヘキシルフタレート（ＤＥＨＰ）、Ｏ－アセチルクエン酸トリエチル（ＯＡＣＴＥ）、Ｏ－アセチルクエン酸トリブチル（ＯＡＣＴＢ）、クエン酸アセチルトリエチル、クエン酸アセチルトリブチル、オレイン酸ブチル、リシノール酸メチルアセチル、セバシン酸ジブチル、トリアセチン、トリブチリン、ブチルフタリルブチルグリコレート、エチルフタリルエチルグリコレート、メチルフタリルエチルグリコレート、ブチルフタリルブチルグリコレートから選ばれたものであることがより好ましい。 <Plasticizer>
The plasticizer is preferably a phosphate ester or a carboxylic acid ester. The plasticizer may be triphenyl phosphate (TPP), tricresyl phosphate (TCP), cresyl diphenyl phosphate, octyl diphenyl phosphate, biphenyl diphenyl phosphate (BDP), trioctyl phosphate, tributyl phosphate, dimethyl phthalate (DMP) ), Diethyl phthalate (DEP), dibutyl phthalate (DBP), dioctyl phthalate (DOP), diphenyl phthalate (DPP), diethyl hexyl phthalate (DEHP), triethyl O-acetylcitrate (OACTE), tributyl O-acetylcitrate ( OACTB), acetyl triethyl citrate, acetyl tributyl citrate, butyl oleate, methyl acetyl ricinoleate, dibutyl sebacate, tria Chin, tributyrin, butyl phthalyl butyl glycolate, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate, and more preferably one selected from butyl phthalyl butyl glycolate.
　さらに、前記可塑剤が、（ジ）ペンタエリスリトールエステル類、グリセロールエステル類、ジグリセロールエステル類であることが好ましい。 Furthermore, the plasticizer is preferably (di) pentaerythritol esters, glycerol esters, or diglycerol esters.
　〈剥離促進剤〉
　剥離促進剤としては、クエン酸のエチルエステル類が例として挙げられる。さらに赤外吸収剤としては例えば特開２００１－１９４５２２号公報に記載されている。 <Peeling accelerator>
Examples of the peeling accelerator include citric acid ethyl esters. Further, infrared absorbers are described in, for example, JP-A No. 2001-194522.
　〈染料〉
　また、本発明では、色相調整のための染料を添加してもよい。染料の含有量は、セルロースエステルに対する質量割合で１０～１０００ｐｐｍが好ましく、５０～５００ｐｐｍがさらに好ましい。この様に染料を含有させることにより、セルロースエステルフィルムのライトパイピングが減少でき、黄色味を改良することができる。 <dye>
In the present invention, a dye for adjusting the hue may be added. The content of the dye is preferably from 10 to 1000 ppm, more preferably from 50 to 500 ppm, by mass ratio with respect to the cellulose ester. By containing the dye in this way, light piping of the cellulose ester film can be reduced, and yellowness can be improved.
　これらの化合物は、セルロースエステル溶液の調製の際に、セルロースエステルや溶媒と共に添加してもよいし、溶液調製中や調製後に添加してもよい。又インライン添加する紫外線吸収剤液に添加してもよい。 These compounds may be added together with the cellulose ester and the solvent during the preparation of the cellulose ester solution, or may be added during or after the solution preparation. Moreover, you may add to the ultraviolet absorber liquid added in-line.
　本発明で用いられる染料は好ましくは下記一般式（１）又は（２）で表される化合物である。 The dye used in the present invention is preferably a compound represented by the following general formula (1) or (2).
Figure JPOXMLDOC01-appb-C000001
Figure JPOXMLDOC01-appb-C000001
　式（１）中、Ｒ１、Ｒ２、Ｒ３、Ｒ４、Ｒ５、Ｒ６、Ｒ７及びＲ８は、各々水素原子、ヒドロキシル基（水酸基）、脂肪族基、芳香族基、複素環基、ハロゲン原子、シアノ基、ニトロ基、－ＣＯＲ９、－ＣＯＯＲ９、－ＮＲ９Ｒ１０、－ＮＲ１０ＣＯＲ１１、－ＮＲ１０ＳＯ２Ｒ１１、－ＣＯＮＲ９Ｒ１０、－ＳＯ２ＮＲ９Ｒ１０、－ＣＯＲ１１、－ＳＯ２Ｒ１１、－ＯＣＯＲ１１、－ＮＲ９ＣＯＮＲ１０Ｒ１１、－ＣＯＮＨＳＯ２Ｒ１１又は－ＳＯ２ＮＨＣＯＲ１１を表し、Ｒ９及びＲ１０は各々水素原子、脂肪族基、芳香族基又は複素環基を表し、Ｒ１１は脂肪族基、芳香族基又は複素環基を表す。Ｒ９とＲ１０は連結して５又は６員環を形成していてもよく、Ｒ１とＲ２又はＲ２とＲ３は各々連結して環を形成してもよい。 In formula (1), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 and R 8 are each a hydrogen atom, hydroxyl group (hydroxyl group), aliphatic group, aromatic group, complex Ring group, halogen atom, cyano group, nitro group, —COR 9 , —COOR 9 , —NR 9 R 10 , —NR 10 COR 11 , —NR 10 SO 2 R 11 , —CONR 9 R 10 , —SO 2 NR 9 R 10, -COR 11, -SO 2 R 11, -OCOR 11, -NR 9 CONR 10 R 11, represents a -CONHSO 2 R 11 or -SO 2 NHCOR 11, R 9 and R 10 are each a hydrogen atom, R 11 represents an aliphatic group, an aromatic group or a heterocyclic group, and R 11 represents an aliphatic group, an aromatic group or a heterocyclic group. R 9 and R 10 may be linked to form a 5- or 6-membered ring, and R 1 and R 2 or R 2 and R 3 may be linked to form a ring.
Figure JPOXMLDOC01-appb-C000002
Figure JPOXMLDOC01-appb-C000002
　式（２）中、Ｒ２１、Ｒ２３及びＲ２４は各々水素原子、ヒドロキシル基（水酸基）、ニトロ基、シアノ基、脂肪族基、芳香族基、－ＣＯＲ２９、－ＣＯＯＲ２９、－ＮＲ２９Ｒ３０、－ＮＲ３０ＣＯＲ３１又は－ＮＲ３０ＳＯ２Ｒ３１を表し、Ｒ２２は脂肪族基又は芳香族基を表し、Ｒ２９及びＲ３０は各々一般式（１）におけるＲ９及びＲ１０と同義であり、Ｒ３１は一般式（１）におけるＲ１１と同義である。但し、Ｒ２１、Ｒ２２、Ｒ２３及びＲ２４のうち１個以上は水素以外の基である。 In the formula (2), R 21 , R 23 and R 24 are each a hydrogen atom, a hydroxyl group (hydroxyl group), a nitro group, a cyano group, an aliphatic group, an aromatic group, —COR 29 , —COOR 29 , —NR 29. R 30 represents —NR 30 COR 31 or —NR 30 SO 2 R 31 , R 22 represents an aliphatic group or an aromatic group, and R 29 and R 30 represent R 9 and R 10 in the general formula (1), respectively. R 31 is synonymous with R 11 in the general formula (1). However, one or more of R 21 , R 22 , R 23 and R 24 are groups other than hydrogen.
　以下に一般式（１）の各基について詳細に説明する。 Hereinafter, each group of the general formula (1) will be described in detail.
　Ｒ１～Ｒ１１で表される脂肪族基は、炭素数１～２０のアルキル基（例えば、メチル、エチル、ｎ－ブチル、イソプロピル、２－エチルヘキシル、ｎ－デシル、ｎ－オクタデシル）、炭素数１～２０のシクロアルキル基（例えば、シクロペンチル、シクロヘキシル）又はアリル基を表し、置換基〔例えば、ハロゲン原子（例えば、Ｆ、Ｃｌ、Ｂｒ、Ｉ）、ヒドロキシル基（水酸基）、シアノ基、ニトロ基、カルボン酸基、炭素数６～１０のアリール基（例えば、フェニル、ナフチル）、炭素数０～２０のアミノ基（例えば、ＮＨ２、ＮＨＣＨ３、Ｎ（Ｃ２Ｈ５）２、Ｎ（Ｃ４Ｈ９）２、Ｎ（Ｃ８Ｈ１７）２、アニリノ、４－メトキシアニリノ）、炭素数１～２０のアミド基（例えば、アセチルアミノ、ヘキサノイルアミノ、ベンゾイルアミノ、オクタデカノイルアミノ）、炭素数１～２０のカルバモイル基（例えば、無置換のカルバモイル、メチルカルバモイル、エチルカルバモイル、オクチルカルバモイル、ヘキサデシルカルバモイル）、炭素数２～２０のエステル基（例えば、メトキシカルボニル、エトキシカルボニル、フェノキシカルボニル、ｎ－ブトキシカルボニル、ドデシルオキシカルボニル）、炭素数１～２０のアルコキシ基又はアリーロキシ基（メトキシ、エトキシ、ブトキシ、イソプロポキシ、ベンジルオキシ、フェノキシ、オクタデシルオキシ）、炭素数１～２０のスルホンアミド基（例えば、メタンスルホンアミド、エタンスルホンアミド、ブタンスルホンアミド、ベンゼンスルホンアミド、オクタンスルホンアミド）、炭素数０～２０のスルファモイル基（例えば、無置換のスルファモイル、メチルスルファモイル、ブチルスルファモイル、デシルスルファモイル）、５又は６員の複素環（例えば、ピリジル、ピラゾリル、モルホリノ、ピペリジノ、ピロリノ、ベンズオキサゾリル）〕を有していてもよい。 The aliphatic group represented by R 1 to R 11 is an alkyl group having 1 to 20 carbon atoms (for example, methyl, ethyl, n-butyl, isopropyl, 2-ethylhexyl, n-decyl, n-octadecyl), carbon number 1 to 20 cycloalkyl groups (for example, cyclopentyl, cyclohexyl) or allyl groups, and substituents [for example, halogen atom (for example, F, Cl, Br, I), hydroxyl group (hydroxyl group), cyano group, nitro group , Carboxylic acid group, aryl group having 6 to 10 carbon atoms (for example, phenyl, naphthyl), amino group having 0 to 20 carbon atoms (for example, NH 2 , NHCH 3 , N (C 2 H 5 ) 2 , N (C 4 H 9 ) 2 , N (C 8 H 17 ) 2 , anilino, 4-methoxyanilino), an amide group having 1 to 20 carbon atoms (for example, acetylamino, hexanoylamino, Benzoylamino, octadecanoylamino), carbamoyl group having 1 to 20 carbon atoms (for example, unsubstituted carbamoyl, methylcarbamoyl, ethylcarbamoyl, octylcarbamoyl, hexadecylcarbamoyl), ester group having 2 to 20 carbon atoms (for example, Methoxycarbonyl, ethoxycarbonyl, phenoxycarbonyl, n-butoxycarbonyl, dodecyloxycarbonyl), alkoxy group having 1 to 20 carbon atoms or aryloxy group (methoxy, ethoxy, butoxy, isopropoxy, benzyloxy, phenoxy, octadecyloxy), carbon A sulfonamide group having 1 to 20 carbon atoms (for example, methanesulfonamide, ethanesulfonamide, butanesulfonamide, benzenesulfonamide, and octanesulfonamide), Famoyl group (eg unsubstituted sulfamoyl, methylsulfamoyl, butylsulfamoyl, decylsulfamoyl), 5- or 6-membered heterocycle (eg pyridyl, pyrazolyl, morpholino, piperidino, pyrrolino, benzoxazolyl) )].
　Ｒ１～Ｒ１１で表される芳香族基は炭素数６～１０のアリール基（例えば、フェニル、ナフチル）を表し、置換基〔例えば、前記した脂肪族基が有してもよい置換基として挙げた各基の他、炭素数１～２０のアルキル基（例えば、メチル、エチル、ブチル、ｔ－ブチル、オクチル）等〕を有していてもよい。 The aromatic group represented by R 1 to R 11 represents an aryl group having 6 to 10 carbon atoms (for example, phenyl or naphthyl), and a substituent [for example, the above-mentioned aliphatic group may have a substituent In addition to the above groups, an alkyl group having 1 to 20 carbon atoms (for example, methyl, ethyl, butyl, t-butyl, octyl, etc.) may be included.
　Ｒ１～Ｒ１１で表される複素環基は５又は６員の複素環（例えば、ピリジン、ピペリジン、モルホリン、ピロリジン、ピラゾール、ピラゾリジン、ピラゾリン、ピラゾロン、ベンズオキサゾール）を表し、置換基（例えば、前記した芳香族基が有してもよい置換基として挙げた各基）を有していてもよい。 The heterocyclic group represented by R 1 to R 11 represents a 5- or 6-membered heterocyclic ring (for example, pyridine, piperidine, morpholine, pyrrolidine, pyrazole, pyrazolidine, pyrazoline, pyrazolone, benzoxazole) and a substituent (for example, Each group mentioned as a substituent which the above-mentioned aromatic group may have may have.
　Ｒ９とＲ１０が連結して形成される５又は６員環としては、モルホリン環、ピペリジン環、ピロリジン環を挙げることができる。Ｒ１とＲ２又はＲ２とＲ３が連結して形成される環としては５又は６員環（例えば、ベンゼン環、フタルイミド環）が好ましい。 Examples of the 5- or 6-membered ring formed by connecting R 9 and R 10 include a morpholine ring, a piperidine ring, and a pyrrolidine ring. The ring formed by connecting R 1 and R 2 or R 2 and R 3 is preferably a 5- or 6-membered ring (for example, a benzene ring or a phthalimide ring).
　次に一般式（２）の各基について説明する。 Next, each group of the general formula (2) will be described.
　Ｒ２１～Ｒ２４で表される脂肪族基は、一般式（１）におけるＲ１～Ｒ１１が表す脂肪族基と同義であり、Ｒ２１～Ｒ２４で表される芳香族基は、一般式（１）におけるＲ１～Ｒ１１が表す芳香族基と同義である。 The aliphatic group represented by R 21 to R 24 has the same meaning as the aliphatic group represented by R 1 to R 11 in the general formula (1), and the aromatic group represented by R 21 to R 24 is a general group. It has the same meaning as the aromatic group represented by R 1 to R 11 in Formula (1).
　これらの添加剤を添加する時期は、ドープ調製工程のいずれのタイミングでもよいが、ドープ調製工程の最後の調製工程に添加剤を添加する工程を行ってもよい。さらにまた、各素材の添加量は機能が発現する限りにおいて特に限定されない。 The timing of adding these additives may be any timing in the dope preparation process, but a process of adding additives to the final preparation process of the dope preparation process may be performed. Furthermore, the amount of each material added is not particularly limited as long as the function is manifested.
　また、セルロースエステルフィルムが多層である場合、各層の添加物の種類や添加量が異なっていてもよい。 In addition, when the cellulose ester film is a multilayer, the type and amount of additives in each layer may be different.
　例えば特開２００１－１５１９０２号公報などに記載されているが、これらは従来から知られている技術である。これら添加剤の種類や添加量の選択によって、セルロースエステルフィルムの動的粘弾性測定機（バイブロン：ＤＶＡ－２２５（アイティー計測制御（株）製）で測定するガラス転移点Ｔｇを７０～１５０℃に、より好ましくは、ガラス転移点Ｔｇを８０～１３５℃にすることが好ましい。 For example, as described in Japanese Patent Application Laid-Open No. 2001-151902, these are conventionally known techniques. Depending on the type and amount of these additives, the glass transition point Tg of the cellulose ester film measured with a dynamic viscoelasticity measuring device (Vibron: DVA-225 (produced by IT Measurement Control Co., Ltd.)) is 70 to 150 ° C. More preferably, the glass transition point Tg is preferably 80 to 135 ° C.
　すなわち、本発明に係るセルロースエステルフィルムは、偏光板加工や液晶表示装置組立ての工程適性の点で、ガラス転移点Ｔｇを上記の範囲とすることが好ましい。 That is, the cellulose ester film according to the present invention preferably has a glass transition point Tg in the above range from the viewpoint of process suitability for polarizing plate processing and liquid crystal display device assembly.
　さらに、添加剤については、発明協会公開技報公技番号２００１－１７４５号（２００１年３月１５日発行、発明協会）ｐ．１６以降に詳細に記載されているものを適宜用いることができる。 Further, regarding additives, the Japan Society for Invention and Innovation, published technical bulletin No. 2001-1745 (issued March 15, 2001, Japan Institute of Invention) p. Those described in detail after 16 can be used as appropriate.
　（リターデーション上昇剤）
　本発明では、セルロースエステルフィルムの光学異方性を第２光学異方性層として使用可能なように、リターデーションを調整する。好ましいリターデーション値を実現するため、リターデーション上昇剤を用いるのが好ましい。 (Retardation increasing agent)
In the present invention, the retardation is adjusted so that the optical anisotropy of the cellulose ester film can be used as the second optical anisotropic layer. In order to realize a preferable retardation value, it is preferable to use a retardation increasing agent.
　リターデーション上昇剤とは、セルロースエステルを含むポリマー成分１００質量部に対して１質量部の添加により、Ｒｔの値をフィルム膜厚１ミクロンあたり０．１１以上上昇させるものである。 The retardation increasing agent increases the value of Rt by 0.11 or more per 1 micron film thickness by adding 1 part by mass with respect to 100 parts by mass of the polymer component containing cellulose ester.
　より好ましくはフィルム膜厚１ミクロンあたり０．２以上、さらに好ましくはフィルム膜厚１ミクロンあたり０．３以上リターデーションを上昇させるものである。 More preferably, the retardation is increased by 0.2 or more per micron of film thickness, more preferably 0.3 or more per micron of film thickness.
　本発明において用いることができるリターデーション上昇剤としては、棒状又は円盤状化合物からなるものを挙げることができる。 Examples of the retardation increasing agent that can be used in the present invention include those composed of rod-shaped or discotic compounds.
　上記棒状又は円盤状化合物としては、少なくとも二つの芳香族環を有する化合物を用いることができる。 As the rod-like or discotic compound, a compound having at least two aromatic rings can be used.
　棒状化合物からなるリターデーション上昇剤の添加量は、セルロースエステルを含むポリマー成分１００質量部に対して０．１～３０質量部であることが好ましく、０．５～２０質量部であることがさらに好ましい。 The addition amount of the retardation increasing agent composed of the rod-like compound is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the polymer component containing the cellulose ester. preferable.
　円盤状のリターデーション上昇剤は、前記セルロースエステルを含むポリマー成分１００質量部に対して、０．０５～３０質量部の範囲で使用することが好ましく、０．１～２０質量部の範囲で使用することがより好ましく、０．２～１５質量部の範囲で使用することがさらに好ましく、０．５～１０質量部の範囲で使用することが最も好ましい。 The disc-shaped retardation increasing agent is preferably used in the range of 0.05 to 30 parts by mass, and in the range of 0.1 to 20 parts by mass with respect to 100 parts by mass of the polymer component containing the cellulose ester. More preferably, it is more preferably used in the range of 0.2 to 15 parts by mass, and most preferably in the range of 0.5 to 10 parts by mass.
　円盤状化合物は、Ｒｔリターデーション発現性において棒状化合物よりも優れているため、特に大きなＲｔリターデーションを必要とする場合には好ましく使用される。 Since the discotic compound is superior to the rod-like compound in terms of Rt retardation expression, it is preferably used when a particularly large Rt retardation is required.
　二種類以上のリターデーション上昇剤を併用してもよい。 Two or more types of retardation increasing agents may be used in combination.
　棒状又は円盤状化合物からなる前記リターデーション上昇剤は、２５０～４００ｎｍの波長領域に最大吸収を有することが好ましく、可視領域に実質的に吸収を有していないことが好ましい。 The retardation increasing agent composed of a rod-like or discotic compound preferably has maximum absorption in the wavelength region of 250 to 400 nm, and preferably has substantially no absorption in the visible region.
　円盤状化合物について説明する。円盤状化合物としては少なくとも二つの芳香族環を有する化合物を用いることができる。本明細書において、「芳香族環」は、芳香族炭化水素環に加えて、芳香族性ヘテロ環を含む。 The discotic compound will be described. As the discotic compound, a compound having at least two aromatic rings can be used. In the present specification, the “aromatic ring” includes an aromatic hetero ring in addition to an aromatic hydrocarbon ring.
　芳香族炭化水素環は、６員環（すなわち、ベンゼン環）であることが特に好ましい。 The aromatic hydrocarbon ring is particularly preferably a 6-membered ring (that is, a benzene ring).
　芳香族性ヘテロ環は一般に、不飽和ヘテロ環である。芳香族性ヘテロ環は、５員環、６員環又は７員環であることが好ましく、５員環又は６員環であることがさらに好ましい。 The aromatic heterocycle is generally an unsaturated heterocycle. The aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring.
　芳香族性ヘテロ環は一般に、最多の二重結合を有する。ヘテロ原子としては、窒素原子、酸素原子及び硫黄原子が好ましく、窒素原子が特に好ましい。 Aromatic heterocycles generally have the most double bonds. As the hetero atom, a nitrogen atom, an oxygen atom and a sulfur atom are preferable, and a nitrogen atom is particularly preferable.
　芳香族性ヘテロ環の例には、フラン環、チオフェン環、ピロール環、オキサゾール環、イソオキサゾール環、チアゾール環、イソチアゾール環、イミダゾール環、ピラゾール環、フラザン環、トリアゾール環、ピラン環、ピリジン環、ピリダジン環、ピリミジン環、ピラジン環及び１，３，５－トリアジン環が含まれる。 Examples of aromatic heterocycles include furan ring, thiophene ring, pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, pyrazole ring, furazane ring, triazole ring, pyran ring, pyridine ring , Pyridazine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring.
　芳香族環としては、ベンゼン環、フラン環、チオフェン環、ピロール環、オキサゾール環、チアゾール環、イミダゾール環、トリアゾール環、ピリジン環、ピリミジン環、ピラジン環及び１，３，５－トリアジン環が好ましく、特に１，３，５－トリアジン環が好ましく用いられる。 As the aromatic ring, benzene ring, furan ring, thiophene ring, pyrrole ring, oxazole ring, thiazole ring, imidazole ring, triazole ring, pyridine ring, pyrimidine ring, pyrazine ring and 1,3,5-triazine ring are preferable, In particular, 1,3,5-triazine ring is preferably used.
　具体的には、例えば特開２００１－１６６１４４号公報に開示の化合物が円盤状化合物として好ましく用いられる。 Specifically, for example, a compound disclosed in JP-A No. 2001-166144 is preferably used as the discotic compound.
　前記円盤状化合物が有する芳香族環の数は、２～２０であることが好ましく、２～１２であることがより好ましく、２～８であることがさらに好ましく、２～６であることが最も好ましい。 The number of aromatic rings contained in the discotic compound is preferably 2 to 20, more preferably 2 to 12, still more preferably 2 to 8, and most preferably 2 to 6. preferable.
　二つの芳香族環の結合関係は、（ａ）縮合環を形成する場合、（ｂ）単結合で直結する場合及び（ｃ）連結基を介して結合する場合に分類できる（芳香族環のため、スピロ結合は形成できない）。結合関係は、（ａ）～（ｃ）のいずれでもよい。 The bonding relationship between two aromatic rings can be classified into (a) when forming a condensed ring, (b) when directly connecting with a single bond, and (c) when connecting via a linking group (for aromatic rings). , Spiro bonds cannot be formed). The bond relationship may be any of (a) to (c).
　（ａ）の縮合環（二つ以上の芳香族環の縮合環）の例には、インデン環、ナフタレン環、アズレン環、フルオレン環、フェナントレン環、アントラセン環、アセナフチレン環、ビフェニレン環、ナフタセン環、ピレン環、インドール環、イソインドール環、ベンゾフラン環、ベンゾチオフェン環、インドリジン環、ベンゾオキサゾール環、ベンゾチアゾール環、ベンゾイミダゾール環、ベンゾトリアゾール環、プリン環、インダゾール環、クロメン環、キノリン環、イソキノリン環、キノリジン環、キナゾリン環、シンノリン環、キノキサリン環、フタラジン環、プテリジン環、カルバゾール環、アクリジン環、フェナントリジン環、キサンテン環、フェナジン環、フェノチアジン環、フェノキサチイン環、フェノキサジン環及びチアントレン環が含まれる。ナフタレン環、アズレン環、インドール環、ベンゾオキサゾール環、ベンゾチアゾール環、ベンゾイミダゾール環、ベンゾトリアゾール環及びキノリン環が好ましい。
（ｂ）の単結合は、二つの芳香族環の炭素原子間の結合であることが好ましい。二以上の単結合で二つの芳香族環を結合して、二つの芳香族環の間に脂肪族環又は非芳香族性複素環を形成してもよい。
（ｃ）の連結基も、二つの芳香族環の炭素原子と結合することが好ましい。連結基は、アルキレン基、アルケニレン基、アルキニレン基、－ＣＯ－、－Ｏ－、－ＮＨ－、－Ｓ－又はそれらの組み合わせであることが好ましい。組み合わせからなる連結基の例を以下に示す。なお、以下の連結基の例の左右の関係は、逆になってもよい。
ｃ１：－ＣＯ－Ｏ－
ｃ２：－ＣＯ－ＮＨ－
ｃ３：－アルキレン－Ｏ－
ｃ４：－ＮＨ－ＣＯ－ＮＨ－
ｃ５：－ＮＨ－ＣＯ－Ｏ－
ｃ６：－Ｏ－ＣＯ－Ｏ－
ｃ７：－Ｏ－アルキレン－Ｏ－
ｃ８：－ＣＯ－アルケニレン－
ｃ９：－ＣＯ－アルケニレン－ＮＨ－
ｃ１０：－ＣＯ－アルケニレン－Ｏ－
ｃ１１：－アルキレン－ＣＯ－Ｏ－アルキレン－Ｏ－ＣＯ－アルキレン－
ｃ１２：－Ｏ－アルキレン－ＣＯ－Ｏ－アルキレン－Ｏ－ＣＯ－アルキレン－Ｏ－
ｃ１３：－Ｏ－ＣＯ－アルキレン－ＣＯ－Ｏ－
ｃ１４：－ＮＨ－ＣＯ－アルケニレン－
ｃ１５：－Ｏ－ＣＯ－アルケニレン－
　芳香族環及び連結基は、置換基を有していてもよい。 Examples of the condensed ring (a condensed ring of two or more aromatic rings) include an indene ring, a naphthalene ring, an azulene ring, a fluorene ring, a phenanthrene ring, an anthracene ring, an acenaphthylene ring, a biphenylene ring, a naphthacene ring, Pyrene ring, indole ring, isoindole ring, benzofuran ring, benzothiophene ring, indolizine ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring, purine ring, indazole ring, chromene ring, quinoline ring, isoquinoline Ring, quinolidine ring, quinazoline ring, cinnoline ring, quinoxaline ring, phthalazine ring, pteridine ring, carbazole ring, acridine ring, phenanthridine ring, xanthene ring, phenazine ring, phenothiazine ring, phenoxathiin ring, phenoxazine ring and thiantole Ring is included. Naphthalene ring, azulene ring, indole ring, benzoxazole ring, benzothiazole ring, benzimidazole ring, benzotriazole ring and quinoline ring are preferred.
The single bond (b) is preferably a bond between carbon atoms of two aromatic rings. Two aromatic rings may be bonded by two or more single bonds to form an aliphatic ring or a non-aromatic heterocyclic ring between the two aromatic rings.
The linking group in (c) is also preferably bonded to carbon atoms of two aromatic rings. The linking group is preferably an alkylene group, an alkenylene group, an alkynylene group, —CO—, —O—, —NH—, —S—, or a combination thereof. Examples of linking groups composed of combinations are shown below. In addition, the relationship between the left and right in the following examples of the linking group may be reversed.
c1: —CO—O—
c2: —CO—NH—
c3: -alkylene-O-
c4: —NH—CO—NH—
c5: —NH—CO—O—
c6: —O—CO—O—
c7: —O-alkylene-O—
c8: -CO-alkenylene-
c9: —CO-alkenylene-NH—
c10: —CO-alkenylene-O—
c11: -alkylene-CO-O-alkylene-O-CO-alkylene-
c12: —O-alkylene-CO—O-alkylene-O—CO-alkylene-O—
c13: —O—CO-alkylene-CO—O—
c14: —NH—CO-alkenylene—
c15: —O—CO-alkenylene—
The aromatic ring and the linking group may have a substituent.
　置換基の例には、ハロゲン原子（Ｆ、Ｃｌ、Ｂｒ、Ｉ）、ヒドロキシル基、カルボキシル基、シアノ基、アミノ基、ニトロ基、スルホ基、カルバモイル基、スルファモイル基、ウレイド基、アルキル基、アルケニル基、アルキニル基、脂肪族アシル基、脂肪族アシルオキシ基、アルコキシ基、アルコキシカルボニル基、アルコキシカルボニルアミノ基、アルキルチオ基、アルキルスルホニル基、脂肪族アミド基、脂肪族スルホンアミド基、脂肪族置換アミノ基、脂肪族置換カルバモイル基、脂肪族置換スルファモイル基、脂肪族置換ウレイド基及び非芳香族性複素環基が含まれる。 Examples of substituents include halogen atoms (F, Cl, Br, I), hydroxyl groups, carboxyl groups, cyano groups, amino groups, nitro groups, sulfo groups, carbamoyl groups, sulfamoyl groups, ureido groups, alkyl groups, alkenyls. Group, alkynyl group, aliphatic acyl group, aliphatic acyloxy group, alkoxy group, alkoxycarbonyl group, alkoxycarbonylamino group, alkylthio group, alkylsulfonyl group, aliphatic amide group, aliphatic sulfonamido group, aliphatic substituted amino group An aliphatic substituted carbamoyl group, an aliphatic substituted sulfamoyl group, an aliphatic substituted ureido group, and a non-aromatic heterocyclic group.
　アルキル基の炭素原子数は、１～８であることが好ましい。環状アルキル基よりも鎖状アルキル基の方が好ましく、直鎖状アルキル基が特に好ましい。アルキル基は、さらに置換基（例、ヒドロキシ基、カルボキシ基、アルコキシ基、アルキル置換アミノ基）を有していてもよい。 The number of carbon atoms in the alkyl group is preferably 1-8. A chain alkyl group is preferable to a cyclic alkyl group, and a linear alkyl group is particularly preferable. The alkyl group may further have a substituent (eg, hydroxy group, carboxy group, alkoxy group, alkyl-substituted amino group).
　アルキル基の（置換アルキル基を含む）例には、メチル基、エチル基、ｎ－ブチル基、ｎ－ヘキシル基、２－ヒドロキシエチル基、４－カルボキシブチル基、２－メトキシエチル基及び２－ジエチルアミノエチル基が含まれる。 Examples of alkyl groups (including substituted alkyl groups) include methyl, ethyl, n-butyl, n-hexyl, 2-hydroxyethyl, 4-carboxybutyl, 2-methoxyethyl and 2-methoxyethyl. A diethylaminoethyl group is included.
　アルケニル基の炭素原子数は、２～８であることが好ましい。環状アルケニル基よりも鎖状アルケニル基の方が好ましく、直鎖状アルケニル基が特に好ましい。アルケニル基は、さらに置換基を有していてもよい。アルケニル基の例には、ビニル基、アリル基及び１－ヘキセニル基が含まれる。 The alkenyl group preferably has 2 to 8 carbon atoms. A chain alkenyl group is preferable to a cyclic alkenyl group, and a linear alkenyl group is particularly preferable. The alkenyl group may further have a substituent. Examples of the alkenyl group include a vinyl group, an allyl group, and a 1-hexenyl group.
　アルキニル基の炭素原子数は、２～８であることが好ましい。環状アルキケニル基よりも鎖状アルキニル基の方が好ましく、直鎖状アルキニル基が特に好ましい。アルキニル基は、さらに置換基を有していてもよい。アルキニル基の例には、エチニル基、１－ブチニル基及び１－ヘキシニル基が含まれる。 The number of carbon atoms of the alkynyl group is preferably 2-8. A chain alkynyl group is preferable to a cyclic alkynyl group, and a linear alkynyl group is particularly preferable. The alkynyl group may further have a substituent. Examples of the alkynyl group include ethynyl group, 1-butynyl group and 1-hexynyl group.
　脂肪族アシル基の炭素原子数は、１～１０であることが好ましい。脂肪族アシル基の例には、アセチル基、プロパノイル基及びブタノイル基が含まれる。 The number of carbon atoms in the aliphatic acyl group is preferably 1-10. Examples of the aliphatic acyl group include an acetyl group, a propanoyl group, and a butanoyl group.
　脂肪族アシルオキシ基の炭素原子数は、１～１０であることが好ましい。脂肪族アシルオキシ基の例には、アセトキシ基が含まれる。 The number of carbon atoms in the aliphatic acyloxy group is preferably 1-10. Examples of the aliphatic acyloxy group include an acetoxy group.
　アルコキシ基の炭素原子数は、１～８であることが好ましい。アルコキシ基は、さらに置換基（例、アルコキシ基）を有していてもよい。アルコキシ基の（置換アルコキシ基を含む）例には、メトキシ基、エトキシ基、ブトキシ基及びメトキシエトキシ基が含まれる。 The number of carbon atoms of the alkoxy group is preferably 1-8. The alkoxy group may further have a substituent (eg, alkoxy group). Examples of the alkoxy group (including a substituted alkoxy group) include a methoxy group, an ethoxy group, a butoxy group, and a methoxyethoxy group.
　アルコキシカルボニル基の炭素原子数は、２～１０であることが好ましい。アルコキシカルボニル基の例には、メトキシカルボニル基及びエトキシカルボニル基が含まれる。 The number of carbon atoms of the alkoxycarbonyl group is preferably 2 to 10. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group.
　アルコキシカルボニルアミノ基の炭素原子数は、２～１０であることが好ましい。アルコキシカルボニルアミノ基の例には、メトキシカルボニルアミノ基及びエトキシカルボニルアミノ基が含まれる。 The number of carbon atoms of the alkoxycarbonylamino group is preferably 2 to 10. Examples of the alkoxycarbonylamino group include a methoxycarbonylamino group and an ethoxycarbonylamino group.
　アルキルチオ基の炭素原子数は、１～１２であることが好ましい。アルキルチオ基の例には、メチルチオ基、エチルチオ基及びオクチルチオ基が含まれる。 The number of carbon atoms of the alkylthio group is preferably 1-12. Examples of the alkylthio group include a methylthio group, an ethylthio group, and an octylthio group.
　アルキルスルホニル基の炭素原子数は、１～８であることが好ましい。アルキルスルホニル基の例には、メタンスルホニル基及びエタンスルホニル基が含まれる。 The number of carbon atoms of the alkylsulfonyl group is preferably 1-8. Examples of the alkylsulfonyl group include a methanesulfonyl group and an ethanesulfonyl group.
　脂肪族アミド基の炭素原子数は、１～１０であることが好ましい。脂肪族アミド基の例には、アセトアミド基が含まれる。 The number of carbon atoms in the aliphatic amide group is preferably 1-10. Examples of the aliphatic amide group include an acetamide group.
　脂肪族スルホンアミド基の炭素原子数は、１～８であることが好ましい。脂肪族スルホンアミド基の例には、メタンスルホンアミド基、ブタンスルホンアミド基及びｎ－オクタンスルホンアミド基が含まれる。 The number of carbon atoms in the aliphatic sulfonamide group is preferably 1-8. Examples of the aliphatic sulfonamido group include a methanesulfonamido group, a butanesulfonamido group and an n-octanesulfonamido group.
　脂肪族置換アミノ基の炭素原子数は、１～１０であることが好ましい。脂肪族置換アミノ基の例には、ジメチルアミノ基、ジエチルアミノ基及び２－カルボキシエチルアミノ基が含まれる。 The number of carbon atoms of the aliphatic substituted amino group is preferably 1-10. Examples of the aliphatic substituted amino group include a dimethylamino group, a diethylamino group, and a 2-carboxyethylamino group.
　脂肪族置換カルバモイル基の炭素原子数は、２～１０であることが好ましい。脂肪族置換カルバモイル基の例には、メチルカルバモイル基及びジエチルカルバモイル基が含まれる。 The number of carbon atoms in the aliphatic substituted carbamoyl group is preferably 2 to 10. Examples of the aliphatic substituted carbamoyl group include a methylcarbamoyl group and a diethylcarbamoyl group.
　脂肪族置換スルファモイル基の炭素原子数は、１～８であることが好ましい。脂肪族置換スルファモイル基の例には、メチルスルファモイル基及びジエチルスルファモイル基が含まれる。 The number of carbon atoms of the aliphatic substituted sulfamoyl group is preferably 1-8. Examples of the aliphatic substituted sulfamoyl group include a methylsulfamoyl group and a diethylsulfamoyl group.
　脂肪族置換ウレイド基の炭素原子数は、２～１０であることが好ましい。脂肪族置換ウレイド基の例には、メチルウレイド基が含まれる。 The number of carbon atoms of the aliphatic substituted ureido group is preferably 2 to 10. Examples of the aliphatic substituted ureido group include a methylureido group.
　非芳香族性複素環基の例には、ピペリジノ基及びモルホリノ基が含まれる。 Examples of non-aromatic heterocyclic groups include piperidino groups and morpholino groups.
　円盤状化合物からなるリターデーション上昇剤の分子量は、３００～８００であることが好ましい。 The molecular weight of the retardation increasing agent comprising a discotic compound is preferably 300 to 800.
　本発明では前述の円盤状化合物の他に、直線的な分子構造を有する棒状化合物も好ましく用いることができる。直線的な分子構造とは、熱力学的に最も安定な構造において棒状化合物の分子構造が直線的であることを意味する。 In the present invention, in addition to the above-mentioned discotic compound, a rod-shaped compound having a linear molecular structure can also be preferably used. The linear molecular structure means that the molecular structure of the rod-like compound is linear in the most thermodynamically stable structure.
　熱力学的に最も安定な構造は、結晶構造解析又は分子軌道計算によって求めることができる。例えば、分子軌道計算ソフト（例、ＷｉｎＭＯＰＡＣ２０００、富士通（株）製）を用いて分子軌道計算を行い、化合物の生成熱が最も小さくなるような分子の構造を求めることができる。 The most thermodynamically stable structure can be obtained by crystal structure analysis or molecular orbital calculation. For example, molecular orbital calculation can be performed using molecular orbital calculation software (eg, WinMOPAC2000, manufactured by Fujitsu Limited) to obtain a molecular structure that minimizes the heat of formation of a compound.
　分子構造が直線的であるとは、上記のように計算して求められる熱力学的に最も安定な構造において、分子構造で主鎖の構成する角度が１４０度以上であることを意味する。 The linear molecular structure means that the angle formed by the main chain in the molecular structure is 140 degrees or more in the thermodynamically most stable structure obtained by calculation as described above.
　棒状化合物としては、少なくとも二つの芳香族環を有するものが好ましく、少なくとも二つの芳香族環を有する棒状化合物としては、下記一般式（３）で表される化合物が好ましい。
一般式（３）：Ａｒ１－Ｌ１－Ａｒ２
　上記一般式（３）において、Ａｒ１及びＡｒ２は、それぞれ独立に、アリール基（芳香族性炭化水素基）、置換アリール基、芳香族性ヘテロ環基又は置換芳香族性ヘテロ環基を表す。アリール基及び置換アリール基の方が、芳香族性ヘテロ環基及び置換芳香族性ヘテロ環基よりも好ましい。 As the rod-shaped compound, those having at least two aromatic rings are preferable, and as the rod-shaped compound having at least two aromatic rings, a compound represented by the following general formula (3) is preferable.
Formula (3): Ar 1 -L 1 -Ar 2
In the general formula (3), Ar 1 and Ar 2 each independently represent an aryl group (aromatic hydrocarbon group), a substituted aryl group, an aromatic heterocyclic group or a substituted aromatic heterocyclic group. . An aryl group and a substituted aryl group are more preferable than an aromatic heterocyclic group and a substituted aromatic heterocyclic group.
　芳香族性へテロ環基のヘテロ環は、一般には不飽和である。芳香族性ヘテロ環は、５員環、６員環又は７員環であることが好ましく、５員環又は６員環であることがさらに好ましい。 The heterocycle of the aromatic heterocyclic group is generally unsaturated. The aromatic heterocycle is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring.
　芳香族性へテロ環は一般に最多の二重結合を有する。ヘテロ原子としては、窒素原子、酸素原子又は硫黄原子が好ましく、窒素原子又は硫黄原子がさらに好ましい。 Aromatic hetero rings generally have the most double bonds. As a hetero atom, a nitrogen atom, an oxygen atom or a sulfur atom is preferable, and a nitrogen atom or a sulfur atom is more preferable.
　芳香族基の芳香族環としては、ベンゼン環、フラン環、チオフェン環、ピロール環、オキサゾール環、チアゾール環、イミダゾール環、トリアゾール環、ピリジン環、ピリミジン環及びピラジン環が好ましく、ベンゼン環が特に好ましい。 As the aromatic ring of the aromatic group, a benzene ring, a furan ring, a thiophene ring, a pyrrole ring, an oxazole ring, a thiazole ring, an imidazole ring, a triazole ring, a pyridine ring, a pyrimidine ring and a pyrazine ring are preferable, and a benzene ring is particularly preferable. .
　置換アリール基及び置換芳香族性ヘテロ環基の置換基の例には、ハロゲン原子（Ｆ、Ｃｌ、Ｂｒ、Ｉ）、ヒドロキシル基、カルボキシル基、シアノ基、アミノ基、アルキルアミノ基（例、メチルアミノ基、エチルアミノ基、ブチルアミノ基、ジメチルアミノ基）、ニトロ基、スルホ基、カルバモイル基、アルキルカルバモイル基（例、Ｎ－メチルカルバモイル基、Ｎ－エチルカルバモイル基、Ｎ，Ｎ－ジメチルカルバモイル基）、スルファモイル基、アルキルスルファモイル基（例、Ｎ－メチルスルファモイル基、Ｎ－エチルスルファモイル基、Ｎ，Ｎ－ジメチルスルファモイル基）、ウレイド基、アルキルウレイド基（例、Ｎ－メチルウレイド基、Ｎ，Ｎ－ジメチルウレイド基、Ｎ，Ｎ，Ｎ’－トリメチルウレイド基）、アルキル基（例、メチル基、エチル基、プロピル基、ブチル基、ペンチル基、ヘプチル基、オクチル基、イソプロピル基、ｓ－ブチル基、ｔ－アミル基、シクロヘキシル基、シクロペンチル基）、アルケニル基（例、ビニル基、アリル基、ヘキセニル基）、アルキニル基（例、エチニル基、ブチニル基）、アシル基（例、ホルミル基、アセチル基、ブチリル基、ヘキサノイル基、ラウリル基）、アシルオキシ基（例、アセトキシ基、ブチリルオキシ基、ヘキサノイルオキシ基、ラウリルオキシ基）、アルコキシ基（例、メトキシ基、エトキシ基、プロポキシ基、ブトキシ基、ペンチルオキシ基、ヘプチルオキシ基、オクチルオキシ基）、アリールオキシ基（例、フェノキシ基）、アルコキシカルボニル基（例、メトキシカルボニル基、エトキシカルボニル基、プロポキシカルボニル基、ブトキシカルボニル基、ペンチルオキシカルボニル基、ヘプチルオキシカルボニル基）、アリールオキシカルボニル基（例、フェノキシカルボニル基）、アルコキシカルボニルアミノ基（例、ブトキシカルボニルアミノ基、ヘキシルオキシカルボニルアミノ基）、アルキルチオ基（例、メチルチオ基、エチルチオ基、プロピルチオ基、ブチルチオ基、ペンチルチオ基、ヘプチルチオ基、オクチルチオ基）、アリールチオ基（例、フェニルチオ基）、アルキルスルホニル基（例、メチルスルホニル基、エチルスルホニル基、プロピルスルホニル基、ブチルスルホニル基、ペンチルスルホニル基、ヘプチルスルホニル基、オクチルスルホニル基）、アミド基（例、アセトアミド基、ブチルアミド基、ヘキシルアミド基、ラウリルアミド基）及び非芳香族性複素環基（例、モルホリル基、ピラジニル基）が含まれる。 Examples of the substituent of the substituted aryl group and the substituted aromatic heterocyclic group include a halogen atom (F, Cl, Br, I), a hydroxyl group, a carboxyl group, a cyano group, an amino group, an alkylamino group (eg, methyl). Amino group, ethylamino group, butylamino group, dimethylamino group), nitro group, sulfo group, carbamoyl group, alkylcarbamoyl group (eg, N-methylcarbamoyl group, N-ethylcarbamoyl group, N, N-dimethylcarbamoyl group) ), Sulfamoyl group, alkylsulfamoyl group (eg, N-methylsulfamoyl group, N-ethylsulfamoyl group, N, N-dimethylsulfamoyl group), ureido group, alkylureido group (eg, N -Methylureido group, N, N-dimethylureido group, N, N, N'-trimethylureido group), alkyl group (eg Methyl, ethyl, propyl, butyl, pentyl, heptyl, octyl, isopropyl, s-butyl, t-amyl, cyclohexyl, cyclopentyl), alkenyl (eg, vinyl, allyl) Group, hexenyl group), alkynyl group (eg, ethynyl group, butynyl group), acyl group (eg, formyl group, acetyl group, butyryl group, hexanoyl group, lauryl group), acyloxy group (eg, acetoxy group, butyryloxy group, Hexanoyloxy group, lauryloxy group), alkoxy group (eg, methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, heptyloxy group, octyloxy group), aryloxy group (eg, phenoxy group), Alkoxycarbonyl group (eg, methoxycarbonyl group, ethoxycarbonyl group) Propoxycarbonyl group, butoxycarbonyl group, pentyloxycarbonyl group, heptyloxycarbonyl group), aryloxycarbonyl group (eg, phenoxycarbonyl group), alkoxycarbonylamino group (eg, butoxycarbonylamino group, hexyloxycarbonylamino group), Alkylthio group (eg, methylthio group, ethylthio group, propylthio group, butylthio group, pentylthio group, heptylthio group, octylthio group), arylthio group (eg, phenylthio group), alkylsulfonyl group (eg, methylsulfonyl group, ethylsulfonyl group, Propylsulfonyl group, butylsulfonyl group, pentylsulfonyl group, heptylsulfonyl group, octylsulfonyl group), amide group (eg, acetamido group, butyramide group, hexylamide group, Laurylamide group) and non-aromatic heterocyclic groups (eg, morpholyl group, pyrazinyl group).
　置換アリール基及び置換芳香族性ヘテロ環基の置換基としては、ハロゲン原子、シアノ基、カルボキシル基、ヒドロキシル基、アミノ基、アルキル置換アミノ基、アシル基、アシルオキシ基、アミド基、アルコキシカルボニル基、アルコキシ基、アルキルチオ基及びアルキル基が好ましい。 Examples of the substituent of the substituted aryl group and the substituted aromatic heterocyclic group include a halogen atom, a cyano group, a carboxyl group, a hydroxyl group, an amino group, an alkyl-substituted amino group, an acyl group, an acyloxy group, an amide group, an alkoxycarbonyl group, Alkoxy groups, alkylthio groups and alkyl groups are preferred.
　アルキルアミノ基、アルコキシカルボニル基、アルコキシ基及びアルキルチオ基のアルキル部分とアルキル基とは、さらに置換基を有していてもよい。 The alkyl moiety of the alkylamino group, alkoxycarbonyl group, alkoxy group, and alkylthio group and the alkyl group may further have a substituent.
　アルキル部分及びアルキル基の置換基の例には、ハロゲン原子、ヒドロキシル、カルボキシル、シアノ、アミノ、アルキルアミノ基、ニトロ、スルホ、カルバモイル、アルキルカルバモイル基、スルファモイル、アルキルスルファモイル基、ウレイド、アルキルウレイド基、アルケニル基、アルキニル基、アシル基、アシルオキシ基、アシルアミノ基、アルコキシ基、アリールオキシ基、アルコキシカルボニル基、アリールオキシカルボニル基、アルコキシカルボニルアミノ基、アルキルチオ基、アリールチオ基、アルキルスルホニル基、アミド基及び非芳香族性複素環基が含まれる。アルキル部分及びアルキル基の置換基としては、ハロゲン原子、ヒドロキシル、アミノ、アルキルアミノ基、アシル基、アシルオキシ基、アシルアミノ基、アルコキシカルボニル基及びアルコキシ基が好ましい。 Examples of alkyl moieties and substituents of alkyl groups include halogen atoms, hydroxyl, carboxyl, cyano, amino, alkylamino groups, nitro, sulfo, carbamoyl, alkylcarbamoyl groups, sulfamoyl, alkylsulfamoyl groups, ureido, alkylureido Group, alkenyl group, alkynyl group, acyl group, acyloxy group, acylamino group, alkoxy group, aryloxy group, alkoxycarbonyl group, aryloxycarbonyl group, alkoxycarbonylamino group, alkylthio group, arylthio group, alkylsulfonyl group, amide group And non-aromatic heterocyclic groups. As the substituent for the alkyl moiety and the alkyl group, a halogen atom, hydroxyl, amino, alkylamino group, acyl group, acyloxy group, acylamino group, alkoxycarbonyl group and alkoxy group are preferable.
　一般式（３）において、Ｌ１は、アルキレン基、アルケニレン基、アルキニレン基、－Ｏ－、－ＣＯ－及びそれらの組み合わせからなる基から選ばれる二価の連結基である。 In the general formula (3), L 1 is a divalent linking group selected from an alkylene group, an alkenylene group, an alkynylene group, —O—, —CO— and a combination thereof.
　アルキレン基は、環状構造を有していてもよい。環状アルキレン基としては、シクロヘキシレンが好ましく、１，４－シクロへキシレンが特に好ましい。鎖状アルキレン基としては、直鎖状アルキレン基の方が分岐を有するアルキレン基よりも好ましい。 The alkylene group may have a cyclic structure. As the cyclic alkylene group, cyclohexylene is preferable, and 1,4-cyclohexylene is particularly preferable. As the chain alkylene group, a linear alkylene group is more preferable than a branched alkylene group.
　アルキレン基の炭素原子数は、１～２０であることが好ましく、より好ましくは１～１５であり、さらに好ましくは１～１０であり、さらに好ましくは１～８であり、最も好ましくは１～６である。 The number of carbon atoms of the alkylene group is preferably 1-20, more preferably 1-15, still more preferably 1-10, still more preferably 1-8, and most preferably 1-6. It is.
　アルケニレン基及びアルキニレン基は、環状構造よりも鎖状構造を有することが好ましく、分岐を有する鎖状構造よりも直鎖状構造を有することがさらに好ましい。 The alkenylene group and the alkynylene group preferably have a chain structure rather than a cyclic structure, and more preferably have a linear structure rather than a branched chain structure.
　アルケニレン基及びアルキニレン基の炭素原子数は、好ましくは２～１０であり、より好ましくは２～８であり、さらに好ましくは２～６であり、さらに好ましくは２～４であり、最も好ましくは２（ビニレン又はエチニレン）である。 The number of carbon atoms of the alkenylene group and the alkynylene group is preferably 2 to 10, more preferably 2 to 8, further preferably 2 to 6, further preferably 2 to 4, and most preferably 2. (Vinylene or ethynylene).
　アリーレン基は、炭素原子数は６～２０であることが好ましく、より好ましくは６～１６であり、さらに好ましくは６～１２である。 The arylene group preferably has 6 to 20 carbon atoms, more preferably 6 to 16, and still more preferably 6 to 12.
　一般式（３）の分子構造において、Ｌ１を挟んで、Ａｒ１とＡｒ２とが形成する角度は、１４０度以上であることが好ましい。 In the molecular structure of the general formula (3), the angle formed by Ar 1 and Ar 2 across L 1 is preferably 140 degrees or more.
　棒状化合物は、文献記載の方法により合成できる。文献としては、Ｍｏｌ．Ｃｒｙｓｔ．Ｌｉｑ．Ｃｒｙｓｔ．，５３巻，２２９ページ（１９７９年）、同８９巻，９３ページ（１９８２年）、同１４５巻，１１１ページ（１９８７年）、同１７０巻，４３ページ（１９８９年）、Ｊ．Ａｍ．Ｃｈｅｍ．Ｓｏｃ．，１１３巻，１３４９ページ（１９９１年）、同１１８巻，５３４６ページ（１９９６年）、同９２巻，１５８２ページ（１９７０年）、Ｊ．Ｏｒｇ．Ｃｈｅｍ．，４０巻，４２０ページ（１９７５年）、Ｔｅｔｒａｈｅｄｒｏｎ，４８巻，１６号，３４３７ページ（１９９２年）を挙げることができる。 The rod-like compound can be synthesized by a method described in the literature. As literature, Mol. Cryst. Liq. Cryst. 53, 229 (1979), 89, 93 (1982), 145, 111 (1987), 170, 43 (1989), J. Am. Am. Chem. Soc. 113, 1349 (1991), 118, 5346 (1996), 92, 1582 (1970); Org. Chem. 40, 420 pages (1975), Tetrahedron, 48, No. 16, page 3437 (1992).
　リターデーション上昇剤として、下記一般式（４）で表される棒状化合物を用いることがさらに好ましい。以下に一般式（４）で表される化合物について説明する。 More preferably, a rod-like compound represented by the following general formula (4) is used as the retardation increasing agent. The compound represented by the general formula (4) will be described below.
Figure JPOXMLDOC01-appb-C000003
Figure JPOXMLDOC01-appb-C000003
　一般式（４）中、Ｒ３１、Ｒ３２、Ｒ３３、Ｒ３４、Ｒ３５、Ｒ３６、Ｒ３７、Ｒ３９及びＲ４０はそれぞれ独立に水素原子又は置換基を表し、Ｒ３１、Ｒ３２、Ｒ３３、Ｒ３４及びＲ３５のうち少なくとも１つは電子供与性基を表す。Ｒ３８は水素原子、炭素数１～４のアルキル基、炭素数２～６のアルキニル基、炭素数６～１２のアリール基、炭素数１～１２のアルコキシ基、炭素数６～１２のアリールオキシ基、炭素数２～１２のアルコキシカルボニル基、炭素数２～１２のアシルアミノ基、シアノ基又はハロゲン原子を表す。 In the general formula (4), R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent, and R 31 , R 32 , R 33 , R 34 and R 35 each represents an electron donating group. R 38 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. Group, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom.
　一般式（４）中、Ｒ３１、Ｒ３２、Ｒ３３、Ｒ３４、Ｒ３５、Ｒ３６、Ｒ３７、Ｒ３９及びＲ４０はそれぞれ独立に水素原子、又は置換基を表し、置換基は後述の置換基Ｔが適用できる。 In General Formula (4), R 31 , R 32 , R 33 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent, and the substituent will be described later. The substituent T can be applied.
　Ｒ３１、Ｒ３２、Ｒ３３、Ｒ３４及びＲ３５の及び少なくとも１つは電子供与性基を表す。好ましくはＲ３１、Ｒ３３又はＲ３５のうちの１つが電子供与性基であり、Ｒ３３が電子供与性基であることがより好ましい。 At least one of R 31 , R 32 , R 33 , R 34 and R 35 represents an electron donating group. It is more preferable that one of R 31 , R 33 or R 35 is an electron donating group and R 33 is an electron donating group.
　電子供与性基とは、Ｈａｍｍｅｔのσｐ値が０以下のものを表し、Ｃｈｅｍ．Ｒｅｖ．，９１，１６５（１９９１）記載のＨａｍｍｅｔのσｐ値が０以下のものが好ましく適用でき、より好ましくは－０．８５～０のものが用いられる。例えば、アルキル基、アルコキシ基、アミノ基、ヒドロキシル基（水酸基）などが挙げられる。 The electron donating group means one having Hammet's σp value of 0 or less. Rev. 91, 165 (1991), those having Hammet's σp value of 0 or less are preferably applicable, and those having −0.85 to 0 are more preferably used. Examples thereof include an alkyl group, an alkoxy group, an amino group, and a hydroxyl group (hydroxyl group).
　電子供与性基として好ましくはアルキル基、アルコキシ基であり、より好ましくはアルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６特に好ましくは炭素数１～４である。）である。 The electron donating group is preferably an alkyl group or an alkoxy group, more preferably an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably carbon atoms). 1 to 4).
　Ｒ３１として好ましくは、水素原子又は電子供与性基であり、より好ましくはアルキル基、アルコキシ基、アミノ基、ヒドロキシル基（水酸基）であり、さらに好ましくは、炭素数１～４のアルキル基、炭素数１～１２のアルコキシ基であり、特に好ましくはアルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６、特に好ましくは炭素数１～４）であり、最も好ましくはメトキシ基である。 R 31 is preferably a hydrogen atom or an electron-donating group, more preferably an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), and still more preferably an alkyl group having 1 to 4 carbon atoms or a carbon atom. An alkoxy group having 1 to 12 carbon atoms, particularly preferably an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms). And most preferably a methoxy group.
　Ｒ３２として好ましくは、水素原子、アルキル基、アルコキシ基、アミノ基、ヒドロキシル基（水酸基）であり、より好ましくは、水素原子、アルキル基、アルコキシ基であり、さらに好ましくは水素原子、アルキル基（好ましくは炭素数１～４、より好ましくはメチル基である。）、アルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６、特に好ましくは炭素数１～４）である。特に好ましくは水素原子、メチル基、メトキシ基である。 R 32 is preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), more preferably a hydrogen atom, an alkyl group, or an alkoxy group, still more preferably a hydrogen atom, an alkyl group ( Preferably, it has 1 to 4 carbon atoms, more preferably a methyl group.), An alkoxy group (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms. Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.
　Ｒ３３として好ましくは、水素原子又は電子供与性基であり、より好ましくは水素原子、アルキル基、アルコキシ基、アミノ基、ヒドロキシル基（水酸基）であり、さらに好ましくは、アルキル基、アルコキシ基であり、特に好ましくはアルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６、特に好ましくは炭素数１～４）である。最も好ましくはｎ－プロポキシ基、エトキシ基、メトキシ基である。 R 33 is preferably a hydrogen atom or an electron donating group, more preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), and still more preferably an alkyl group or an alkoxy group. Particularly preferably, it is an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms). Most preferred are n-propoxy group, ethoxy group and methoxy group.
　Ｒ３４として好ましくは、水素原子又は電子供与性基であり、より好ましくは水素原子、アルキル基、アルコキシ基、アミノ基、ヒドロキシル基（水酸基）であり、さらに好ましくは、水素原子、炭素数１～４のアルキル基、炭素数１～１２のアルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６、特に好ましくは炭素数１～４）であり、特に好ましくは水素原子、炭素数１～４のアルキル基、炭素数１～４のアルコキシ基であり、最も好ましくは水素原子、メチル基、メトキシ基である。 R 34 is preferably a hydrogen atom or an electron donating group, more preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), and still more preferably a hydrogen atom or a carbon number of 1 to An alkyl group having 4 carbon atoms and an alkoxy group having 1 to 12 carbon atoms (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms). And particularly preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms, and most preferably a hydrogen atom, a methyl group and a methoxy group.
　Ｒ３５として好ましくは、水素原子、アルキル基、アルコキシ基、アミノ基、ヒドロキシル基（水酸基）であり、より好ましくは、水素原子、アルキル基、アルコキシ基であり、さらに好ましくは水素原子、アルキル基（好ましくは炭素数１～４より好ましくはメチル基である。）、アルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６特に好ましくは炭素数１～４）である。特に好ましくは水素原子、メチル基、メトキシ基である。 R 35 is preferably a hydrogen atom, an alkyl group, an alkoxy group, an amino group, or a hydroxyl group (hydroxyl group), more preferably a hydrogen atom, an alkyl group, or an alkoxy group, still more preferably a hydrogen atom, an alkyl group ( Preferably, it has 1 to 4 carbon atoms, more preferably a methyl group), an alkoxy group (preferably 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably carbon atoms). 1 to 4). Particularly preferred are a hydrogen atom, a methyl group and a methoxy group.
　Ｒ３６、Ｒ３７、Ｒ３９及びＲ４０として、好ましくは水素原子、炭素数１～１２のアルキル基、炭素数１～１２のアルコキシ基、ハロゲン原子であり、より好ましくは、水素原子、ハロゲン原子であり、さらに好ましくは水素原子である。 R 36 , R 37 , R 39 and R 40 are preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or a halogen atom, more preferably a hydrogen atom or a halogen atom. And more preferably a hydrogen atom.
　Ｒ３８は水素原子、炭素数１～４のアルキル基、炭素数２～６のアルキニル基、炭素数６～１２のアリール基、炭素数１～１２のアルコキシ基、炭素数６～１２のアリールオキシ基、炭素数２～１２のアルコキシカルボニル基、炭素数２～１２のアシルアミノ基、シアノ基又はハロゲン原子を表し、可能な場合には置換基を有してもよく、置換基としては後述の置換基Ｔが適用できる。 R 38 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. Group, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom, which may have a substituent if possible. The group T can be applied.
　Ｒ３８として好ましくは炭素数１～４のアルキル基、炭素数２～６のアルキニル基、炭素数６～１２のアリール基、炭素数１～１２のアルコキシ基、炭素数２～１２のアリールオキシ基であり、より好ましくは、炭素数６～１２のアリール基、炭素数１～１２のアルコキシ基、炭素数６～１２のアリールオキシ基であり、さらに好ましくは炭素数１～１２のアルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６、特に好ましくは炭素数１～４である。）であり、特に好ましくは、メトキシ基、エトキシ基、ｎ－プロポキシ基、ｉｓｏ－プロポキシ基、ｎ－ブトキシ基である。 R 38 is preferably an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 2 to 12 carbon atoms. More preferably, it is an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms, and more preferably an alkoxy group having 1 to 12 carbon atoms (preferably Is 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, particularly preferably 1 to 4 carbon atoms, and particularly preferably a methoxy group, an ethoxy group, n-propoxy group, iso-propoxy group and n-butoxy group.
　一般式（４）のうちより好ましくは下記一般式（４－Ａ）である。 Of the general formula (4), the following general formula (4-A) is more preferable.
Figure JPOXMLDOC01-appb-C000004
Figure JPOXMLDOC01-appb-C000004
　一般式（４－Ａ）中、Ｒ４１はアルキル基を表す。Ｒ３１、Ｒ３２、Ｒ３４、Ｒ３５、Ｒ３６、Ｒ３７、Ｒ３９及びＲ４０はそれぞれ独立に水素原子、又は置換基を表す。Ｒ３８は水素原子、炭素数１～４のアルキル基、炭素数２～６のアルキニル基、炭素数６～１２のアリール基、炭素数１～１２のアルコキシ基、炭素数６～１２のアリールオキシ基、炭素数２～１２のアルコキシカルボニル基、炭素数２～１２のアシルアミノ基、シアノ基又はハロゲン原子を表す。 In the general formula (4-A), R 41 represents an alkyl group. R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent. R 38 represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms. Group, an alkoxycarbonyl group having 2 to 12 carbon atoms, an acylamino group having 2 to 12 carbon atoms, a cyano group, or a halogen atom.
　一般式（４－Ａ）中、Ｒ３１、Ｒ３２、Ｒ３４、Ｒ３５、Ｒ３６、Ｒ３７、Ｒ３８、Ｒ３９及びＲ４０はそれぞれ一般式（４）におけるそれらと同義であり、また好ましい範囲も同様である。 In the general formula (4-A), R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 38 , R 39 and R 40 are respectively synonymous with those in the general formula (4), and The preferable range is also the same.
　一般式（４－Ａ）中、Ｒ４１は炭素数１～１２のアルキル基を表し、Ｒ４１で表されるアルキル基は直鎖でも分岐があってもよく、またさらに置換基を有してもよいが、好ましくは炭素数１～１２のアルキル基、より好ましくは炭素数１～８アルキル基、さらに好ましくは炭素数１～６アルキル基、特に好ましくは炭素数１～４のアルキル基（例えば、メチル基、エチル基、ｎ－プロピル基、ｉｓｏ－プロピル基、ｎ－ブチル基、ｉｓｏ－ブチル基、ｔｅｒｔ－ブチル基などが挙げられる）を表す。 In the general formula (4-A), R 41 represents an alkyl group having 1 to 12 carbon atoms, and the alkyl group represented by R 41 may be linear or branched, and further has a substituent. However, it is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms, still more preferably an alkyl group having 1 to 6 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms (for example, Methyl group, ethyl group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, tert-butyl group, and the like.
　一般式（４）のうちより好ましくは下記一般式（４－Ｂ）である。 Of the general formula (4), the following general formula (4-B) is more preferable.
Figure JPOXMLDOC01-appb-C000005
Figure JPOXMLDOC01-appb-C000005
　一般式（４－Ｂ）中、Ｒ３１、Ｒ３２、Ｒ３４、Ｒ３５、Ｒ３６、Ｒ３７、Ｒ３９及びＲ４０はそれぞれ独立に水素原子、又は置換基を表す。Ｒ４１は炭素数１～１２のアルキル基を表す。 In general formula (4-B), R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 39 and R 40 each independently represent a hydrogen atom or a substituent. R 41 represents an alkyl group having 1 to 12 carbon atoms.
　Ｘは炭素数１～４のアルキル基、炭素数２～６のアルキニル基、炭素数６～１２のアリール基、炭素数１～１２のアルコキシ基、炭素数６～１２のアリールオキシ基、炭素数２～１２のアルコキシカルボニル基、炭素数２～１２のアシルアミノ基、シアノ基又はハロゲン原子を表す。 X represents an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, It represents a 2-12 alkoxycarbonyl group, an acylamino group having 2-12 carbon atoms, a cyano group or a halogen atom.
　一般式（４－Ｂ）中、Ｒ３１、Ｒ３２、Ｒ３４、Ｒ３５、Ｒ３６、Ｒ３７、Ｒ３９、及びＲ４０は一般式（４）におけるそれらと同義であり、また好ましい範囲も同様である。 In the general formula (4-B), R 31 , R 32 , R 34 , R 35 , R 36 , R 37 , R 39 , and R 40 are synonymous with those in the general formula (4), and preferred ranges are also included. It is the same.
　一般式（４－Ｂ）中、Ｒ４１は一般式（４－Ａ）におけるそれらと同義であり、また好ましい範囲も同様である。 In the general formula (4-B), R 41 has the same meaning as that in the general formula (4-A), and the preferred range is also the same.
　一般式（４－Ｂ）中、Ｘは炭素数１～４のアルキル基、炭素数２～６のアルキニル基、炭素数６～１２のアリール基、炭素数１～１２のアルコキシ基、炭素数６～１２のアリールオキシ基、炭素数２～１２のアルコキシカルボニル基、炭素数２～１２のアシルアミノ基、シアノ基又はハロゲン原子を表す。 In general formula (4-B), X represents an alkyl group having 1 to 4 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or 6 carbon atoms. Represents an aryloxy group having 12 carbon atoms, an alkoxycarbonyl group having 2-12 carbon atoms, an acylamino group having 2-12 carbon atoms, a cyano group, or a halogen atom.
　Ｒ３１、Ｒ３２、Ｒ３４、及びＲ３５がすべて水素原子の場合にはＸとして好ましくはアルキル基、アルキニル基、アリール基、アルコキシ基、アリールオキシ基であり、より好ましくは、アリール基、アルコキシ基、アリールオキシ基であり、さらに好ましくはアルコキシ基（好ましくは炭素数１～１２、より好ましくは炭素数１～８、さらに好ましくは炭素数１～６、特に好ましくは炭素数１～４である。）であり、特に好ましくは、メトキシ基、メトキシ基、ｎ－プロポキシ基、ｉｓｏ－プロポキシ基、ｎ－ブトキシ基である。 When all of R 31 , R 32 , R 34 and R 35 are hydrogen atoms, X is preferably an alkyl group, alkynyl group, aryl group, alkoxy group or aryloxy group, more preferably an aryl group, alkoxy group An aryloxy group, more preferably an alkoxy group (preferably having 1 to 12 carbon atoms, more preferably 1 to 8 carbon atoms, still more preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms). And particularly preferably a methoxy group, a methoxy group, an n-propoxy group, an iso-propoxy group or an n-butoxy group.
　Ｒ３１、Ｒ３２、Ｒ３４、及びＲ３５のうち少なくとも１つが置換基の場合にはＸとして好ましくはアルキニル基、アリール基、アルコキシカルボニル基、シアノ基、であり、より好ましくはアリール基（好ましくは炭素数６～１２）、シアノ基、アルコキシカルボニル基（好ましくは炭素数２～１２）であり、さらに好ましくはアリール基（好ましくは炭素数６～１２のアリール基であり、より好ましくはフェニル基、ｐ－シアノフェニル基、ｐ－メトキシフェニルである。）、アルコキシカルボニル基（好ましくは炭素２～１２、より好ましくは炭素数２～６、さらに好ましくは炭素数２～４、特に好ましくはメトキシカルボニル、エトキシカルボニル、ｎ－プロポキシカルボニルである。）、シアノ基であり、特に好ましくは、フェニル基、メトキシカルボニル基、エトキシカルボニル基、ｎ－プロポキシカルボニル基、シアノ基である。 When at least one of R 31 , R 32 , R 34 , and R 35 is a substituent, X is preferably an alkynyl group, an aryl group, an alkoxycarbonyl group, or a cyano group, more preferably an aryl group (preferably Is a cyano group or an alkoxycarbonyl group (preferably 2 to 12 carbon atoms), more preferably an aryl group (preferably an aryl group having 6 to 12 carbon atoms, more preferably a phenyl group). , P-cyanophenyl group, and p-methoxyphenyl group), an alkoxycarbonyl group (preferably having 2 to 12, more preferably 2 to 6, more preferably 2 to 4, and particularly preferably methoxycarbonyl). , Ethoxycarbonyl, n-propoxycarbonyl), cyano group, particularly preferably An enyl group, a methoxycarbonyl group, an ethoxycarbonyl group, an n-propoxycarbonyl group, and a cyano group.
　一般式（４）のうちさらに好ましくは下記一般式（４－Ｃ）である。 Of the general formula (4), the following general formula (4-C) is more preferable.
Figure JPOXMLDOC01-appb-C000006
Figure JPOXMLDOC01-appb-C000006
　一般式（４－Ｃ）中、Ｒ３１、Ｒ３２、Ｒ３４、Ｒ３５、Ｒ４１及びＸは一般式（４－Ｂ）におけるそれらと同義であり、また好ましい範囲も同様である。 In general formula (4-C), R 31 , R 32 , R 34 , R 35 , R 41 and X have the same meanings as those in general formula (4-B), and preferred ranges are also the same.
　一般式（４）で表される化合物の中でより好ましいのは下記一般式（４－Ｄ）で表される化合物である。 Among the compounds represented by the general formula (4), a compound represented by the following general formula (4-D) is more preferable.
Figure JPOXMLDOC01-appb-C000007
Figure JPOXMLDOC01-appb-C000007
　一般式（４－Ｄ）中、Ｒ３２、Ｒ３４及びＲ３５は一般式（４－Ｃ）におけるそれらと同義であり、また好ましい範囲も同様である。Ｒ５１、Ｒ５２はそれぞれ独立に炭素数１～４のアルキル基である。Ｘ１は炭素数６～１２のアリール基、炭素数２～１２のアルコキシカルボニル基、又はシアノ基である。 In general formula (4-D), R 32 , R 34 and R 35 have the same meanings as those in general formula (4-C), and preferred ranges are also the same. R 51 and R 52 are each independently an alkyl group having 1 to 4 carbon atoms. X 1 is an aryl group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, or a cyano group.
　Ｒ５１は炭素数１～４のアルキル基を表し、好ましくは炭素数１～３のアルキル基であり、より好ましくはエチル基、メチル基である。 R 51 represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, and more preferably an ethyl group or a methyl group.
　Ｒ５２は炭素数１～４のアルキル基を表し、好ましくは炭素数１～３のアルキル基であり、より好ましくはエチル基、メチル基であり、さらに好ましくはメチル基である。 R 52 represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, more preferably an ethyl group or a methyl group, and still more preferably a methyl group.
　Ｘ１は炭素数６～１２のアリール基、炭素２～１２アルコキシカルボニル基、又はシアノ基であり、好ましくは炭素数６～１０のアリール基、炭素数２～６アルコキシカルボニル基、シアノ基であり、より好ましくはフェニル基、ｐ－シアノフェニル基、ｐ－メトキシフェニル基、メトキシカルボニル、エトキシカルボニル、ｎ－プロポキシカルボニル、シアノ基であり、さらに好ましくは、フェニル基、メトキシカルボニル基、エトキシカルボニル基、ｎ－プロポキシカルボニル基、シアノ基である。 X 1 is an aryl group having 6 to 12 carbon atoms, an alkoxycarbonyl group having 2 to 12 carbon atoms, or a cyano group, preferably an aryl group having 6 to 10 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, or a cyano group. More preferably a phenyl group, a p-cyanophenyl group, a p-methoxyphenyl group, a methoxycarbonyl, an ethoxycarbonyl, an n-propoxycarbonyl, a cyano group, and still more preferably a phenyl group, a methoxycarbonyl group, an ethoxycarbonyl group, n-propoxycarbonyl group, cyano group.
　一般式（４）のうち最も好ましくは下記一般式（４－Ｅ）である。 Of the general formula (4), the following general formula (4-E) is most preferable.
Figure JPOXMLDOC01-appb-C000008
Figure JPOXMLDOC01-appb-C000008
　一般式（４－Ｅ）中、Ｒ３２’、Ｒ３４’及びＲ３５’は、それぞれ独立に水素原子、又は置換基を表すが、いずれか１つは－ＯＲ４３で表される基である（Ｒ４３は炭素数１～４のアルキル基である）。Ｒ３２’、Ｒ３４’及びＲ３５’がそれぞれ表す置換基の範囲及びその好ましい範囲については、上記と同様である。Ｒ５１、Ｒ５２、及びＸ１は一般式（４－Ｄ）におけるそれらと同義であり、また好ましい範囲も同様である。 In the general formula (4-E), R 32 ′ , R 34 ′ and R 35 ′ each independently represent a hydrogen atom or a substituent, and any one of them is a group represented by —OR 43. (R 43 is an alkyl group having 1 to 4 carbon atoms). The ranges of substituents represented by R 32 ′ , R 34 ′ and R 35 ′ and preferred ranges thereof are the same as described above. R 51 , R 52 and X 1 have the same meanings as those in formula (4-D), and preferred ranges are also the same.
　一般式（４－Ｅ）中、Ｒ３２’、Ｒ３４’及びＲ３５’のいずれか１つは－ＯＲ４３で表される基であり（Ｒ４３は炭素数１～４のアルキル基である。）、好ましくはＲ３４’、及びＲ３５’が－ＯＲ４３で表される基であり、より好ましくはＲ３４’が－ＯＲ４３で表される基である。 In the general formula (4-E), any one of R 32 ′ , R 34 ′ and R 35 ′ is a group represented by —OR 43 (R 43 is an alkyl group having 1 to 4 carbon atoms). ), Preferably R 34 ′ and R 35 ′ are groups represented by —OR 43 , and more preferably R 34 ′ is a group represented by —OR 43 .
　Ｒ４３は炭素数１～４のアルキル基を表し、好ましくは炭素数１～３のアルキル基であり、より好ましくはエチル基、メチル基であり、さらに好ましくはメチル基である。 R 43 represents an alkyl group having 1 to 4 carbon atoms, preferably an alkyl group having 1 to 3 carbon atoms, more preferably an ethyl group or a methyl group, and still more preferably a methyl group.
　以下に前述の置換基Ｔについて説明する。 Hereinafter, the aforementioned substituent T will be described.
　置換基Ｔとしては例えばアルキル基（好ましくは炭素数１～２０、より好ましくは炭素数１～１２、特に好ましくは炭素数１～８であり、例えばメチル、エチル、ｉｓｏ－プロピル、ｔｅｒｔ－ブチル、ｎ－オクチル、ｎ－デシル、ｎ－ヘキサデシル、シクロプロピル、シクロペンチル、シクロヘキシルなどが挙げられる。）、アルケニル基（好ましくは炭素数２～２０、より好ましくは炭素数２～１２、特に好ましくは炭素数２～８であり、例えばビニル、アリル、２－ブテニル、３－ペンテニルなどが挙げられる。）、アルキニル基（好ましくは炭素数２～２０、より好ましくは炭素数２～１２、特に好ましくは炭素数２～８であり、例えばプロパルギル、３－ペンチニルなどが挙げられる。）、アリール基（好ましくは炭素数６～３０、より好ましくは炭素数６～２０、特に好ましくは炭素数６～１２であり、例えばフェニル、ｐ－メチルフェニル、ナフチルなどが挙げられる。）、置換又は未置換のアミノ基（好ましくは炭素数０～２０、より好ましくは炭素数０～１０、特に好ましくは炭素数０～６であり、例えばアミノ、メチルアミノ、ジメチルアミノ、ジエチルアミノ、ジベンジルアミノなどが挙げられる。）、アルコキシ基（好ましくは炭素数１～２０、より好ましくは炭素数１～１２、特に好ましくは炭素数１～８であり、例えばメトキシ、エトキシ、ブトキシなどが挙げられる。）、アリールオキシ基（好ましくは炭素数６～２０、より好ましくは炭素数６～１６、特に好ましくは炭素数６～１２であり、例えばフェニルオキシ、２－ナフチルオキシなどが挙げられる。）、アシル基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばアセチル、ベンゾイル、ホルミル、ピバロイルなどが挙げられる。）、アルコキシカルボニル基（好ましくは炭素数２～２０、より好ましくは炭素数２～１６、特に好ましくは炭素数２～１２であり、例えばメトキシカルボニル、エトキシカルボニルなどが挙げられる。）、アリールオキシカルボニル基（好ましくは炭素数７～２０、より好ましくは炭素数７～１６、特に好ましくは炭素数７～１０であり、例えばフェニルオキシカルボニルなどが挙げられる。）、アシルオキシ基（好ましくは炭素数２～２０、より好ましくは炭素数２～１６、特に好ましくは炭素数２～１０であり、例えばアセトキシ、ベンゾイルオキシなどが挙げられる。）、アシルアミノ基（好ましくは炭素数２～２０、より好ましくは炭素数２～１６、特に好ましくは炭素数２～１０であり、例えばアセチルアミノ、ベンゾイルアミノなどが挙げられる。）、アルコキシカルボニルアミノ基（好ましくは炭素数２～２０、より好ましくは炭素数２～１６、特に好ましくは炭素数２～１２であり、例えばメトキシカルボニルアミノなどが挙げられる。）、アリールオキシカルボニルアミノ基（好ましくは炭素数７～２０、より好ましくは炭素数７～１６、特に好ましくは炭素数７～１２であり、例えばフェニルオキシカルボニルアミノなどが挙げられる。）、スルホニルアミノ基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばメタンスルホニルアミノ、ベンゼンスルホニルアミノなどが挙げられる。）、スルファモイル基（好ましくは炭素数０～２０、より好ましくは炭素数０～１６、特に好ましくは炭素数０～１２であり、例えばスルファモイル、メチルスルファモイル、ジメチルスルファモイル、フェニルスルファモイルなどが挙げられる。）、カルバモイル基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばカルバモイル、メチルカルバモイル、ジエチルカルバモイル、フェニルカルバモイルなどが挙げられる。）、アルキルチオ基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばメチルチオ、エチルチオなどが挙げられる。）、アリールチオ基（好ましくは炭素数６～２０、より好ましくは炭素数６～１６、特に好ましくは炭素数６～１２であり、例えばフェニルチオなどが挙げられる。）、スルホニル基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばメシル、トシルなどが挙げられる。）、スルフィニル基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばメタンスルフィニル、ベンゼンスルフィニルなどが挙げられる。）、ウレイド基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばウレイド、メチルウレイド、フェニルウレイドなどが挙げられる。）、リン酸アミド基（好ましくは炭素数１～２０、より好ましくは炭素数１～１６、特に好ましくは炭素数１～１２であり、例えばジエチルリン酸アミド、フェニルリン酸アミドなどが挙げられる。）、ヒドロキシ基、メルカプト基、ハロゲン原子（例えばフッ素原子、塩素原子、臭素原子、ヨウ素原子）、シアノ基、スルホ基、カルボキシル基、ニトロ基、ヒドロキサム酸基、スルフィノ基、ヒドラジノ基、イミノ基、ヘテロ環基（好ましくは炭素数１～３０、より好ましくは１～１２であり、ヘテロ原子としては、例えば窒素原子、酸素原子、硫黄原子、具体的には例えばイミダゾリル、ピリジル、キノリル、フリル、ピペリジル、モルホリノ、ベンゾオキサゾリル、ベンズイミダゾリル、ベンズチアゾリルなどが挙げられる。）、シリル基（好ましくは、炭素数３～４０、より好ましくは炭素数３～３０、特に好ましくは、炭素数３～２４であり、例えば、トリメチルシリル、トリフェニルシリルなどが挙げられる）などが挙げられる。これらの置換基はさらに置換されてもよい。 Examples of the substituent T include an alkyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms, such as methyl, ethyl, iso-propyl, tert-butyl, and n-octyl, n-decyl, n-hexadecyl, cyclopropyl, cyclopentyl, cyclohexyl, etc.), an alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably carbon number). 2 to 8, for example, vinyl, allyl, 2-butenyl, 3-pentenyl, etc.), alkynyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably carbon number) 2 to 8, for example, propargyl, 3-pentynyl, etc.), aryl group (preferably having 6 to 3 carbon atoms) More preferably 6 to 20 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenyl, p-methylphenyl, naphthyl, etc.), a substituted or unsubstituted amino group (preferably having 0 carbon atoms). To 20, more preferably 0 to 10 carbon atoms, particularly preferably 0 to 6 carbon atoms, such as amino, methylamino, dimethylamino, diethylamino, dibenzylamino, etc.), an alkoxy group (preferably carbon 1 to 20, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as methoxy, ethoxy, butoxy, etc.), an aryloxy group (preferably having 6 to 20 carbon atoms, More preferably, it has 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenyloxy, 2-naphthyloxy and the like. An acyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include acetyl, benzoyl, formyl, and pivaloyl). An alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, etc.), an aryloxycarbonyl group (Preferably having 7 to 20 carbon atoms, more preferably having 7 to 16 carbon atoms, particularly preferably 7 to 10 carbon atoms, such as phenyloxycarbonyl), acyloxy group (preferably having 2 to 20 carbon atoms) More preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, such as acetoxy, Examples include benzoyloxy. ), An acylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, and examples thereof include acetylamino and benzoylamino), alkoxycarbonylamino group (Preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms such as methoxycarbonylamino), aryloxycarbonylamino group (preferably having carbon number) 7 to 20, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, such as phenyloxycarbonylamino, and the like, and sulfonylamino groups (preferably 1 to 20 carbon atoms, more preferably Has 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms. , Benzenesulfonylamino, etc.), sulfamoyl groups (preferably having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms, such as sulfamoyl, methylsulfamoyl) , Dimethylsulfamoyl, phenylsulfamoyl, etc.), a carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms. For example, carbamoyl , Methylcarbamoyl, diethylcarbamoyl, phenylcarbamoyl, etc.), an alkylthio group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as methylthio, Ethylthio etc.), arylthio group (preferably Has 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, such as phenylthio, and the like, and a sulfonyl group (preferably 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as mesyl, tosyl, etc.), sulfinyl group (preferably 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably Has 1 to 12 carbon atoms, such as methanesulfinyl, benzenesulfinyl, etc.), ureido group (preferably 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms). For example, ureido, methylureido, phenylureido, etc.), phosphoric acid amide groups (preferably having 1 to 20 carbon atoms, More preferably, it has 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include diethyl phosphoric acid amide and phenyl phosphoric acid amide. ), Hydroxy group, mercapto group, halogen atom (eg fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, Heterocyclic group (preferably having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms). Examples of the hetero atom include a nitrogen atom, an oxygen atom, a sulfur atom, specifically, for example, imidazolyl, pyridyl, quinolyl, furyl, piperidyl , Morpholino, benzoxazolyl, benzimidazolyl, benzthiazolyl, etc.), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms). For example, trimethylsilyl, triphenylsilyl, etc.) . These substituents may be further substituted.
　また、置換基が二つ以上ある場合は、同じでも異なってもよい。また、可能な場合には互いに連結して環を形成してもよい。 In addition, when there are two or more substituents, they may be the same or different. If possible, they may be linked together to form a ring.
　以下に一般式（４）で表される化合物に関して具体例をあげて詳細に説明するが、本発明は以下の具体例によって何ら限定されることはない。 Hereinafter, the compound represented by the general formula (4) will be described in detail with specific examples, but the present invention is not limited to the following specific examples.
Figure JPOXMLDOC01-appb-C000009
Figure JPOXMLDOC01-appb-C000009
Figure JPOXMLDOC01-appb-C000010
Figure JPOXMLDOC01-appb-C000010
Figure JPOXMLDOC01-appb-C000011
Figure JPOXMLDOC01-appb-C000011
Figure JPOXMLDOC01-appb-C000012
Figure JPOXMLDOC01-appb-C000012
Figure JPOXMLDOC01-appb-C000013
Figure JPOXMLDOC01-appb-C000013
Figure JPOXMLDOC01-appb-C000014
Figure JPOXMLDOC01-appb-C000014
　前記一般式（４）で表される化合物は置換安息香酸とフェノール誘導体の一般的なエステル反応によって合成でき、エステル結合形成反応であればどのような反応を用いてもよい。例えば、置換安息香酸を酸ハロゲン化物に官能基変換した後、フェノールと縮合する方法、縮合剤あるいは触媒を用いて置換安息香酸とフェノール誘導体を脱水縮合する方法などが挙げられる。 The compound represented by the general formula (4) can be synthesized by a general ester reaction of a substituted benzoic acid and a phenol derivative, and any reaction may be used as long as it is an ester bond forming reaction. Examples thereof include a method of converting a substituted benzoic acid to an acid halide and then condensing with phenol, a method of dehydrating condensation of a substituted benzoic acid and a phenol derivative using a condensing agent or a catalyst, and the like.
　製造プロセス等を考慮すると置換安息香酸を酸ハロゲン化物に官能基変換した後、フェノールと縮合する方法が好ましい。 Considering the production process and the like, a method in which a substituted benzoic acid is converted to an acid halide with a functional group and then condensed with phenol is preferable.
　反応溶媒として炭化水素系溶媒（好ましくはトルエン、キシレンが挙げられる。）、エーテル系溶媒（好ましくはジメチルエーテル、テトラヒドロフラン、ジオキサンなどが挙げられる）、ケトン系溶媒、エステル系溶媒、アセトニトリル、ジメチルホルムアミド、ジメチルアセトアミドなどを用いることができる。 Reaction solvents include hydrocarbon solvents (preferably toluene and xylene), ether solvents (preferably dimethyl ether, tetrahydrofuran, dioxane, etc.), ketone solvents, ester solvents, acetonitrile, dimethylformamide, dimethyl Acetamide or the like can be used.
　これらの溶媒は単独でも数種を混合して用いてもよく、反応溶媒として好ましくはトルエン、アセトニトリル、ジメチルホルムアミド、ジメチルアセトアミドである。 These solvents may be used alone or in admixture of several kinds, and preferred reaction solvents are toluene, acetonitrile, dimethylformamide, and dimethylacetamide.
　反応温度としては、好ましくは０～１５０℃、より好ましくは０～１００℃、さらに好ましくは０～９０℃であり、特に好ましくは２０℃～９０℃である。 The reaction temperature is preferably 0 to 150 ° C., more preferably 0 to 100 ° C., further preferably 0 to 90 ° C., and particularly preferably 20 ° C. to 90 ° C.
　本反応には塩基を用いないのが好ましく、塩基を用いる場合には有機塩基、無機塩基のどちらでもよく、好ましくは有機塩基であり、ピリジン、３級アルキルアミン（好ましくはトリエチルアミン、エチルジイソプルピルアミンなどが挙げられる）である。 In this reaction, it is preferable not to use a base. When a base is used, either an organic base or an inorganic base may be used, preferably an organic base such as pyridine, tertiary alkylamine (preferably triethylamine, ethyldiisopropyl). Pyramine and the like).
　溶液の紫外線吸収スペクトルにおいて最大吸収波長（λｍａｘ）が２５０ｎｍより短波長である棒状化合物を、二種類以上併用してもよい。 Two or more rod-like compounds having a maximum absorption wavelength (λmax) shorter than 250 nm in the ultraviolet absorption spectrum of the solution may be used in combination.
　（マット剤微粒子）
　本発明に係るセルロースエステルフィルムには、マット剤として微粒子を加えることが好ましい。本発明に使用される微粒子としては、二酸化珪素、二酸化チタン、酸化アルミニウム、酸化ジルコニウム、炭酸カルシウム、炭酸カルシウム、タルク、クレイ、焼成カオリン、焼成珪酸カルシウム、水和ケイ酸カルシウム、ケイ酸アルミニウム、ケイ酸マグネシウム及びリン酸カルシウムを挙げることができる。 (Matting agent fine particles)
It is preferable to add fine particles as a matting agent to the cellulose ester film according to the present invention. The fine particles used in the present invention include silicon dioxide, titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, silica Mention may be made of magnesium and calcium phosphates.
　微粒子はケイ素を含むものが濁度を低くする点で好ましく、特に二酸化珪素が好ましい。二酸化珪素の微粒子は、１次平均粒子径が２０ｎｍ以下であり、且つ見かけ比重が７０ｇ／リットル以上であるものが好ましい。 Fine particles containing silicon are preferable from the viewpoint of reducing turbidity, and silicon dioxide is particularly preferable. The fine particles of silicon dioxide preferably have a primary average particle diameter of 20 nm or less and an apparent specific gravity of 70 g / liter or more.
　１次粒子の平均径が５～１６ｎｍと小さいものがフィルムのヘイズを下げることができより好ましい。見かけ比重は９０～２００ｇ／リットル以上が好ましく、１００～２００ｇ／リットル以上がさらに好ましい。 It is more preferable that the average primary particle size is as small as 5 to 16 nm because the haze of the film can be lowered. The apparent specific gravity is preferably 90 to 200 g / liter or more, and more preferably 100 to 200 g / liter or more.
　見かけ比重が大きい程、高濃度の分散液を作ることが可能になり、ヘイズ、凝集物が良化するため好ましい。 A larger apparent specific gravity is preferable because a high-concentration dispersion can be produced, and haze and aggregates are improved.
　前記二酸化珪素微粒子を用いる場合の使用量は、セルロースエステルを含むポリマー成分１００質量部に対して０．０１～０．３質量部とするのが好ましい。 When the silicon dioxide fine particles are used, the amount used is preferably 0.01 to 0.3 parts by mass with respect to 100 parts by mass of the polymer component containing cellulose ester.
　これらの微粒子は、通常平均粒子径が０．１～３．０μｍの２次粒子を形成し、これらの微粒子はフィルム中では、１次粒子の凝集体として存在し、フィルム表面に０．１～３．０μｍの凹凸を形成させる。 These fine particles usually form secondary particles having an average particle diameter of 0.1 to 3.0 μm, and these fine particles are present in the film as aggregates of primary particles, and 0.1 to 3.0 μm on the film surface. An unevenness of 3.0 μm is formed.
　２次平均粒子径は０．２μｍ以上１．５μｍ以下が好ましく、０．４μｍ以上１．２μｍ以下がさらに好ましく、０．６μｍ以上１．１μｍ以下が最も好ましい。 The secondary average particle diameter is preferably 0.2 μm to 1.5 μm, more preferably 0.4 μm to 1.2 μm, and most preferably 0.6 μm to 1.1 μm.
　１．５μｍよりも大きいとヘイズが強くなり、０．２μｍよりも小さいときしみ防止効果が小さくなる。 When it is larger than 1.5 μm, the haze becomes strong, and when it is smaller than 0.2 μm, the effect of preventing stain is reduced.
　１次、２次粒子径はフィルム中の粒子を走査型電子顕微鏡で観察し、粒子に外接する円の直径をもって粒径とする。また、場所を変えて粒子２００個を観察し、その平均値をもって平均粒子径とする。 The primary and secondary particle diameters are determined by observing particles in the film with a scanning electron microscope and using the diameter of a circle circumscribing the particles as the particle diameter. Also, 200 particles are observed at different locations, and the average value is taken as the average particle diameter.
　二酸化珪素の微粒子は、例えば、アエロジルＲ９７２、Ｒ９７２Ｖ、Ｒ９７４、Ｒ８１２、２００、２００Ｖ、３００、Ｒ２０２、ＯＸ５０、ＴＴ６００（以上日本アエロジル（株）製）などの市販品を使用することができる。 As the silicon dioxide fine particles, for example, commercially available products such as Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600 (manufactured by Nippon Aerosil Co., Ltd.) can be used.
　酸化ジルコニウムの微粒子は、例えば、アエロジルＲ９７６及びＲ８１１（以上日本アエロジル（株）製）の商品名で市販されており、使用することができる。 Zirconium oxide fine particles are commercially available under the trade names of Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) and can be used.
　これらの中でアエロジル２００Ｖ、アエロジルＲ９７２Ｖが１次平均粒子径が２０ｎｍ以下であり、且つ見かけ比重が７０ｇ／リットル以上である二酸化珪素の微粒子であり、光学フィルムの濁度を低く保ちながら、摩擦係数をさげる効果が大きいため特に好ましい。 Among these, Aerosil 200V and Aerosil R972V are fine particles of silicon dioxide having a primary average particle diameter of 20 nm or less and an apparent specific gravity of 70 g / liter or more, and the coefficient of friction is maintained while keeping the turbidity of the optical film low. It is particularly preferable because it has a great effect of reducing the effect.
　本発明において２次平均粒子径の小さな粒子を有するセルロースエステルフィルムを得るために、微粒子の分散液を調製する際にいくつかの手法が考えられる。 In order to obtain a cellulose ester film having particles having a small secondary average particle diameter in the present invention, several methods are conceivable when preparing a dispersion of fine particles.
　例えば、溶剤と微粒子を撹拌混合した微粒子分散液をあらかじめ調製し、この微粒子分散液を別途用意した少量のセルロースエステル溶液に加えて撹拌溶解し、さらにメインのセルロースエステルドープ液と混合する方法がある。 For example, there is a method in which a fine particle dispersion liquid prepared by stirring and mixing a solvent and fine particles is prepared in advance, and this fine particle dispersion solution is added to a small amount of a separately prepared cellulose ester solution, stirred and dissolved, and further mixed with the main cellulose ester dope solution. .
　この方法は、二酸化珪素微粒子の分散性がよく、二酸化珪素微粒子がさらに再凝集しにくい点で好ましい調製方法である。ほかにも、溶剤に少量のセルロースエステルを加え、撹拌溶解した後、これに微粒子を加えて分散機で分散を行い、これを微粒子添加液とし、この微粒子添加液をインラインミキサーでドープ液と十分混合する方法もある。 This method is a preferable preparation method in that the dispersibility of the silicon dioxide fine particles is good and the silicon dioxide fine particles are more difficult to reaggregate. In addition, after adding a small amount of cellulose ester to the solvent and dissolving with stirring, add the fine particles to this and disperse with a disperser, and use this as a fine particle additive solution. There is also a method of mixing.
　本発明は、これらの方法に限定されないが、二酸化珪素微粒子を溶剤などと混合して分散するときの二酸化珪素の濃度は５～３０質量％が好ましく、１０～２５質量％がさらに好ましく、１５～２０質量％が最も好ましい。 The present invention is not limited to these methods, but the concentration of silicon dioxide when the silicon dioxide fine particles are mixed and dispersed with a solvent or the like is preferably 5 to 30% by mass, more preferably 10 to 25% by mass, Most preferred is 20% by weight.
　分散濃度が高い方が添加量に対する液濁度は低くなり、ヘイズ、凝集物が良化するため好ましい。最終的なセルロースエステルのドープ溶液中でのマット剤の添加量は１ｍ２あたり０．０１～１．０ｇが好ましく、０．０３～０．３ｇがさらに好ましく、０．０８～０．１６ｇが最も好ましい。 A higher dispersion concentration is preferable because the liquid turbidity with respect to the added amount is lowered, and haze and aggregates are improved. The addition amount of the matting agent in the final cellulose ester dope solution is preferably 0.01 to 1.0 g, more preferably 0.03 to 0.3 g, and most preferably 0.08 to 0.16 g per 1 m 2. preferable.
　使用される溶剤は低級アルコール類としては、好ましくはメチルアルコール、エチルアルコール、プロピルアルコール、イソプロピルアルコール、ブチルアルコール等が挙げられる。低級アルコール以外の溶媒としては特に限定されないが、セルロースエステルの製膜時に用いられる溶剤を用いることが好ましい。 The solvent used is preferably lower alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol and the like. Although it does not specifically limit as solvents other than a lower alcohol, It is preferable to use the solvent used at the time of film forming of a cellulose ester.
　次に、本発明に係るセルロースエステルが溶解される前記有機溶媒について記述する。 Next, the organic solvent in which the cellulose ester according to the present invention is dissolved will be described.
　本発明においては、有機溶媒として、塩素系有機溶媒を主溶媒とする塩素系溶媒と塩素系有機溶媒を含まない非塩素系溶媒とのいずれをも用いることができる。 In the present invention, as the organic solvent, any of a chlorinated solvent containing a chlorinated organic solvent as a main solvent and a non-chlorinated solvent not containing a chlorinated organic solvent can be used.
　（塩素系溶媒）
　本発明に係るセルロースエステルの溶液を作製するに際しては、主溶媒として塩素系有機溶媒が好ましく用いられる。 (Chlorine solvent)
In preparing the cellulose ester solution according to the present invention, a chlorinated organic solvent is preferably used as the main solvent.
　本発明においては、セルロースエステルが溶解し溶液流延製膜できる範囲において、その目的が達成できる限りはその塩素系有機溶媒の種類は特に限定されない。 In the present invention, the kind of the chlorinated organic solvent is not particularly limited as long as the object can be achieved within a range in which the cellulose ester can be dissolved and solution casting can be performed.
　これらの塩素系有機溶媒は、好ましくはジクロロメタン、クロロホルムである。特にジクロロメタンが好ましい。また、塩素系有機溶媒以外の有機溶媒を混合することも特に問題ない。その場合は、ジクロロメタンは有機溶媒全体量中少なくとも５０質量％使用することが必要である。 These chlorinated organic solvents are preferably dichloromethane and chloroform. Particularly preferred is dichloromethane. In addition, there is no particular problem in mixing an organic solvent other than the chlorinated organic solvent. In that case, it is necessary to use at least 50% by mass of dichloromethane in the total amount of the organic solvent.
　本発明で塩素系有機溶剤と併用される他の有機溶媒について以下に記す。すなわち、好ましい他の有機溶媒としては、炭素原子数が３～１２のエステル、ケトン、エーテル、アルコール、炭化水素などから選ばれる溶媒が好ましい。 Other organic solvents used in combination with the chlorinated organic solvent in the present invention are described below. That is, as another preferable organic solvent, a solvent selected from esters, ketones, ethers, alcohols, hydrocarbons and the like having 3 to 12 carbon atoms is preferable.
　エステル、ケトン、エーテル及びアルコールは、環状構造を有していてもよい。エステル、ケトン及びエーテルの官能基（すなわち、－Ｏ－、－ＣＯ－及びＣＯＯ－）のいずれかを二つ以上有する化合物も溶媒として用いることができ、たとえばアルコール性ヒドロキシル基（水酸基）のような他の官能基を同時に有していてもよい。 The ester, ketone, ether and alcohol may have a cyclic structure. A compound having two or more functional groups of esters, ketones and ethers (that is, —O—, —CO— and COO—) can also be used as a solvent, such as an alcoholic hydroxyl group (hydroxyl group). You may have another functional group simultaneously.
　二種類以上の官能基を有する溶媒の場合、その炭素原子数はいずれかの官能基を有する化合物の規定範囲内であればよい。炭素原子数が３～１２のエステル類の例には、エチルホルメート、プロピルホルメート、ペンチルホルメート、メチルアセテート、エチルアセテート及びペンチルアセテート等が挙げられる。 In the case of a solvent having two or more types of functional groups, the number of carbon atoms may be within the specified range of the compound having any functional group. Examples of esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.
　炭素原子数が３～１２のケトン類の例には、アセトン、メチルエチルケトン、ジエチルケトン、ジイソブチルケトン、シクロペンタノン、シクロヘキサノン及びメチルシクロヘキサノン等が挙げられる。 Examples of ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, and methylcyclohexanone.
　炭素原子数が３～１２のエーテル類の例には、ジイソプロピルエーテル、ジメトキシメタン、ジメトキシエタン、１，４－ジオキサン、１，３－ジオキソラン、テトラヒドロフラン、アニソール及びフェネトール等が挙げられる。二種類以上の官能基を有する有機溶媒の例には、２－エトキシエチルアセテート、２－メトキシエタノール及び２－ブトキシエタノール等が挙げられる。 Examples of ethers having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole. Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.
　また塩素系有機溶媒と併用されるアルコールとしては、好ましくは直鎖であっても分枝を有していても環状であってもよく、その中でも飽和脂肪族炭化水素であることが好ましい。アルコールのヒドロキシル基（水酸基）は、第一級～第三級のいずれであってもよい。 Also, the alcohol used in combination with the chlorinated organic solvent may be linear, branched or cyclic, and among them, saturated aliphatic hydrocarbon is preferable. The hydroxyl group (hydroxyl group) of the alcohol may be any of primary to tertiary.
　アルコールの例には、メタノール、エタノール、１－プロパノール、２－プロパノール、１－ブタノール、２－ブタノール、ｔ－ブタノール、１－ペンタノール、２－メチル－２－ブタノール及びシクロヘキサノールが含まれる。なおアルコールとしては、フッ素系アルコールも用いられる。例えば、２－フルオロエタノール、２，２，２－トリフルオロエタノール、２，２，３，３－テトラフルオロ－１－プロパノールなども挙げられる。 Examples of the alcohol include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, 2-methyl-2-butanol and cyclohexanol. As the alcohol, fluorine-based alcohol is also used. Examples thereof include 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol and the like.
　さらに炭化水素は、直鎖であっても分岐を有していても環状であってもよい。芳香族炭化水素と脂肪族炭化水素のいずれも用いることができる。脂肪族炭化水素は、飽和であっても不飽和であってもよい。 Further, the hydrocarbon may be linear, branched or cyclic. Either aromatic hydrocarbons or aliphatic hydrocarbons can be used. The aliphatic hydrocarbon may be saturated or unsaturated.
　炭化水素の例には、シクロヘキサン、ヘキサン、ベンゼン、トルエン及びキシレンが含まれる。 Examples of hydrocarbons include cyclohexane, hexane, benzene, toluene and xylene.
　塩素系有機溶媒と他の有機溶媒との組み合わせ例としては以下の組成を挙げることができるが、これらに限定されるものではない。
・ジクロロメタン／メタノール／エタノール／ブタノール（８０／１０／５／５、質量部）、
・ジクロロメタン／アセトン／メタノール／プロパノール（８０／１０／５／５、質量部）、
・ジクロロメタン／メタノール／ブタノール／シクロヘキサン（８０／１０／５／５、質量部）、
・ジクロロメタン／メチルエチルケトン／メタノール／ブタノール（８０／１０／５／５、質量部）、
・ジクロロメタン／アセトン／メチルエチルケトン／エタノール／イソプロパノール（７５／８／５／５／７、質量部）
・ジクロロメタン／シクロペンタノン／メタノール／イソプロパノール（８０／７／５／８、質量部）
・ジクロロメタン／酢酸メチル／ブタノール（８０／１０／１０、質量部）、
・ジクロロメタン／シクロヘキサノン／メタノール／ヘキサン（７０／２０／５／５、質量部）、
・ジクロロメタン／メチルエチルケトン／アセトン／メタノール／エタノール（５０／２０／２０／５／５、質量部）、
・ジクロロメタン／１、３ジオキソラン／メタノール／エタノール（７０／２０／５／５、質量部）、
・ジクロロメタン／ジオキサン／アセトン／メタノール／エタノール（６０／２０／１０／５／５、質量部）、
・ジクロロメタン／アセトン／シクロペンタノン／エタノール／イソブタノール／シクロヘキサン（６５／１０／１０／５／５／５、質量部）、
・ジクロロメタン／メチルエチルケトン／アセトン／メタノール／エタノール（７０／１０／１０／５／５、質量部）、
・ジクロロメタン／アセトン／酢酸エチル／エタノール／ブタノール／ヘキサン（６５／１０／１０／５／５／５、質量部）、
・ジクロロメタン／アセト酢酸メチル／メタノール／エタノール（６５／２０／１０／５、質量部）、
・ジクロロメタン／シクロペンタノン／エタノール／ブタノール（６５／２０／１０／５、質量部）、
などを挙げることができる。 Examples of combinations of chlorinated organic solvents and other organic solvents include the following compositions, but are not limited thereto.
Dichloromethane / methanol / ethanol / butanol (80/10/5/5, parts by mass),
Dichloromethane / acetone / methanol / propanol (80/10/5/5, parts by mass),
Dichloromethane / methanol / butanol / cyclohexane (80/10/5/5, parts by mass),
Dichloromethane / methyl ethyl ketone / methanol / butanol (80/10/5/5, parts by mass),
・ Dichloromethane / acetone / methyl ethyl ketone / ethanol / isopropanol (75/8/5/5/7, parts by mass)
・ Dichloromethane / cyclopentanone / methanol / isopropanol (80/7/5/8, part by mass)
Dichloromethane / methyl acetate / butanol (80/10/10, parts by mass),
Dichloromethane / cyclohexanone / methanol / hexane (70/20/5/5, parts by mass)
Dichloromethane / methyl ethyl ketone / acetone / methanol / ethanol (50/20/20/5/5, parts by mass),
Dichloromethane / 1, 3 dioxolane / methanol / ethanol (70/20/5/5, parts by mass),
Dichloromethane / dioxane / acetone / methanol / ethanol (60/20/10/5/5, parts by mass),
Dichloromethane / acetone / cyclopentanone / ethanol / isobutanol / cyclohexane (65/10/10/5/5/5, parts by mass)
Dichloromethane / methyl ethyl ketone / acetone / methanol / ethanol (70/10/10/5/5, parts by mass),
Dichloromethane / acetone / ethyl acetate / ethanol / butanol / hexane (65/10/10/5/5/5, parts by mass),
Dichloromethane / methyl acetoacetate / methanol / ethanol (65/20/10/5, parts by mass),
Dichloromethane / cyclopentanone / ethanol / butanol (65/20/10/5, parts by mass),
And so on.
　（非塩素系溶媒）
　次に、本発明に係るセルロースエステルの溶液を作製するに際して好ましく用いられる非塩素系有機溶媒について記載する。 (Non-chlorine solvent)
Next, the non-chlorine organic solvent that is preferably used in preparing the cellulose ester solution according to the present invention will be described.
　本発明においては、セルロースエステルが溶解し溶液流延製膜できる範囲において、その目的が達成できる限りは非塩素系有機溶媒は特に限定されない。 In the present invention, the non-chlorine organic solvent is not particularly limited as long as the object can be achieved within a range in which the cellulose ester can be dissolved and solution casting can be performed.
　本発明で用いられる非塩素系有機溶媒は、炭素原子数が３～１２のエステル、ケトン、エーテルから選ばれる溶媒が好ましい。 The non-chlorine organic solvent used in the present invention is preferably a solvent selected from esters, ketones and ethers having 3 to 12 carbon atoms.
　エステル、ケトン及び、エーテルは、環状構造を有していてもよい。エステル、ケトン及びエーテルの官能基（すなわち、－Ｏ－、－ＣＯ－及びＣＯＯ－）のいずれかを２つ以上有する化合物も、主溶媒として用いることができ、たとえばアルコール性ヒドロキシル基（水酸基）のような他の官能基を有していてもよい。 Ester, ketone and ether may have a cyclic structure. A compound having two or more functional groups of esters, ketones and ethers (that is, —O—, —CO— and COO—) can also be used as a main solvent, for example, an alcoholic hydroxyl group (hydroxyl group) Such other functional groups may be included.
　二種類以上の官能基を有する主溶媒の場合、その炭素原子数はいずれかの官能基を有する化合物の規定範囲内であればよい。 In the case of the main solvent having two or more kinds of functional groups, the number of carbon atoms may be within the specified range of the compound having any functional group.
　炭素原子数が３～１２のエステル類の例には、エチルホルメート、プロピルホルメート、ペンチルホルメート、メチルアセテート、エチルアセテート及びペンチルアセテートが挙げられる。 Examples of esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.
　炭素原子数が３～１２のケトン類の例には、アセトン、メチルエチルケトン、ジエチルケトン、ジイソブチルケトン、シクロペンタノン、シクロヘキサノン及びメチルシクロヘキサノンが挙げられる。炭素原子数が３～１２のエーテル類の例には、ジイソプロピルエーテル、ジメトキシメタン、ジメトキシエタン、１，４－ジオキサン、１，３－ジオキソラン、テトラヒドロフラン、アニソール及びフェネトールが挙げられる。 Examples of ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone and methylcyclohexanone. Examples of ethers having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole and phenetole.
　二種類以上の官能基を有する有機溶媒の例には、２－エトキシエチルアセテート、２－メトキシエタノール及び２－ブトキシエタノールが挙げられる。 Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol and 2-butoxyethanol.
　以上のセルロースエステルに用いられる非塩素系有機溶媒については、前述のいろいろな観点から選定されるが、好ましくは以下のとおりである。 The non-chlorine organic solvent used in the above cellulose ester is selected from the various viewpoints described above, and is preferably as follows.
　すなわち、非塩素系溶媒としては、前記非塩素系有機溶媒を主溶媒とする混合溶媒が好ましく、互いに異なる３種類以上の溶媒の混合溶媒であって、第１の溶媒が酢酸メチル、酢酸エチル、蟻酸メチル、蟻酸エチル、アセトン、ジオキソラン、ジオキサンから選ばれる少なくとも一種あるいは或いはそれらの混合液であり、第２の溶媒が炭素原子数が４～７のケトン類又はアセト酢酸エステルから選ばれ、第３の溶媒として炭素数が１～１０のアルコール又は炭化水素、より好ましくは炭素数１～８のアルコールから選ばれる、混合溶媒である。 That is, the non-chlorine solvent is preferably a mixed solvent containing the non-chlorine organic solvent as a main solvent, and is a mixed solvent of three or more different solvents, wherein the first solvent is methyl acetate, ethyl acetate, At least one selected from methyl formate, ethyl formate, acetone, dioxolane, and dioxane, or a mixture thereof; the second solvent is selected from ketones having 4 to 7 carbon atoms or acetoacetate; The solvent is a mixed solvent selected from alcohols or hydrocarbons having 1 to 10 carbon atoms, more preferably alcohols having 1 to 8 carbon atoms.
　なお第１の溶媒が、二種以上の溶媒の混合液である場合は、第２の溶媒がなくてもよい。第１の溶媒は、さらに好ましくは酢酸メチル、アセトン、蟻酸メチル、蟻酸エチルあるいはこれらの混合物であり、第２の溶媒は、メチルエチルケトン、シクロペンタノン、シクロヘキサノン、アセチル酢酸メチルが好ましく、これらの混合溶媒であってもよい。 Note that when the first solvent is a mixture of two or more solvents, the second solvent may not be present. The first solvent is more preferably methyl acetate, acetone, methyl formate, ethyl formate, or a mixture thereof, and the second solvent is preferably methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl acetyl acetate, or a mixed solvent thereof. It may be.
　第３の溶媒であるアルコールは、直鎖であっても分枝を有していても環状であってもよく、その中でも飽和脂肪族炭化水素であることが好ましい。 The alcohol as the third solvent may be linear, branched or cyclic, and is preferably a saturated aliphatic hydrocarbon.
　アルコールのヒドロキシル基（水酸基）は、第一級～第三級のいずれであってもよい。アルコールの例には、メタノール、エタノール、１－プロパノール、２－プロパノール、１－ブタノール、２－ブタノール、ｔ－ブタノール、１－ペンタノール、２－メチル－２－ブタノール及びシクロヘキサノールが含まれる。 The hydroxyl group (hydroxyl group) of the alcohol may be any of primary to tertiary. Examples of the alcohol include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, t-butanol, 1-pentanol, 2-methyl-2-butanol and cyclohexanol.
　なお、アルコールとしては、フッ素系アルコールも用いられる。例えば、２－フルオロエタノール、２，２，２－トリフルオロエタノール、２，２，３，３－テトラフルオロ－１－プロパノールなども挙げられる。 In addition, as the alcohol, a fluorinated alcohol is also used. Examples thereof include 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol and the like.
　さらに炭化水素は、直鎖であっても分岐を有していても環状であってもよい。芳香族炭化水素と脂肪族炭化水素のいずれも用いることができる。 Further, the hydrocarbon may be linear, branched or cyclic. Either aromatic hydrocarbons or aliphatic hydrocarbons can be used.
　脂肪族炭化水素は、飽和であっても不飽和であってもよい。炭化水素の例には、シクロヘキサン、ヘキサン、ベンゼン、トルエン及びキシレンが含まれる。 The aliphatic hydrocarbon may be saturated or unsaturated. Examples of hydrocarbons include cyclohexane, hexane, benzene, toluene and xylene.
　これらの第３の溶媒であるアルコール及び炭化水素は単独でもよいし２種類以上の混合物でもよく特に限定されない。 These third solvents, which are alcohols and hydrocarbons, may be used alone or as a mixture of two or more, and are not particularly limited.
　第３の溶媒としては、好ましい具体的化合物は、アルコールとしてはメタノール、エタノール、１－プロパノール、２－プロパノール、１－ブタノール、２－ブタノール、及びシクロヘキサノール、シクロヘキサン、ヘキサンを挙げることができ、特にはメタノール、エタノール、１－プロパノール、２－プロパノール、１－ブタノールである。 As the third solvent, preferred specific compounds include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and cyclohexanol, cyclohexane, and hexane as alcohols. Are methanol, ethanol, 1-propanol, 2-propanol, 1-butanol.
　以上の三種類の混合溶媒の混合割合は、混合溶媒全体量中、第１の溶媒が２０～９５質量％、第２の溶媒が２～６０質量％さらに第３の溶媒が２～３０質量％の比率で含まれることが好ましく、さらに第１の溶媒が３０～９０質量％であり、第２の溶媒が３～５０質量％、さらに第３のアルコールが３～２５質量％含まれることが好ましい。 The mixing ratio of the above three mixed solvents is that the first solvent is 20 to 95% by mass, the second solvent is 2 to 60% by mass, and the third solvent is 2 to 30% by mass in the total amount of the mixed solvent. Preferably, the first solvent is 30 to 90% by mass, the second solvent is 3 to 50% by mass, and the third alcohol is preferably 3 to 25% by mass. .
　また、特に第１の溶媒が３０～９０質量％であり、第２の溶媒が３～３０質量％、第３の溶媒がアルコールであり３～１５質量％含まれることが好ましい。 In particular, it is preferable that the first solvent is 30 to 90% by mass, the second solvent is 3 to 30% by mass, and the third solvent is alcohol and 3 to 15% by mass.
　以上の本発明で用いられる非塩素系有機溶媒は、さらに詳細には発明協会公開技報公技番号２００１－１７４５号（２００１年３月１５日発行、発明協会）ｐ．１２－１６に詳細に記載されている。前記非塩素系有機溶媒の好ましい組み合わせを以下挙げるが、これらに限定されるものではない。
・酢酸メチル／アセトン／メタノール／エタノール／ブタノール（７５／１０／５／５／５、質量部）、
・酢酸メチル／アセトン／メタノール／エタノール／プロパノール（７５／１０／５／５／５、質量部）、
・酢酸メチル／アセトン／メタノール／ブタノール／シクロヘキサン（７５／１０／５／５／５、質量部）、
・酢酸メチル／アセトン／エタノール／ブタノール（８１／８／７／４、質量部）
・酢酸メチル／アセトン／エタノール／ブタノール（８２／１０／４／４、質量部）
・酢酸メチル／アセトン／エタノール／ブタノール（８０／１０／４／６、質量部）
・酢酸メチル／メチルエチルケトン／メタノール／ブタノール（８０／１０／５／５、質量部）、
・酢酸メチル／アセトン／メチルエチルケトン／エタノール／イソプロパノール（７５／８／５／５／７、質量部）、
・酢酸メチル／シクロペンタノン／メタノール／イソプロパノール（８０／７／５／８、質量部）、
・酢酸メチル／アセトン／ブタノール（８５／１０／５、質量部）、
・酢酸メチル／シクロペンタノン／アセトン／メタノール／ブタノール（６０／１５／１４／５／６、質量部）、
・酢酸メチル／シクロヘキサノン／メタノール／ヘキサン（７０／２０／５／５、質量部）、
・酢酸メチル／メチルエチルケトン／アセトン／メタノール／エタノール（５０／２０／２０／５／５、質量部）、
・酢酸メチル／１、３－ジオキソラン／メタノール／エタノール（７０／２０／５／５、質量部）、
・酢酸メチル／ジオキサン／アセトン／メタノール／エタノール（６０／２０／１０／５／５、質量部）、
・酢酸メチル／アセトン／シクロペンタノン／エタノール／イソブタノール／シクロヘキサン（６５／１０／１０／５／５／５、質量部）、
・ギ酸メチル／メチルエチルケトン／アセトン／メタノール／エタノール（５０／２０／２０／５／５、質量部）、
・ギ酸メチル／アセトン／酢酸エチル／エタノール／ブタノール／ヘキサン（６５／１０／１０／５／５／５、質量部）、
・アセトン／アセト酢酸メチル／メタノール／エタノール（６５／２０／１０／５、質量部）、
・アセトン／シクロペンタノン／エタノール／ブタノール（６５／２０／１０／５、質量部）、
・アセトン／１，３－ジオキソラン／エタノール／ブタノール（６５／２０／１０／５、質量部）、
・１、３－ジオキソラン／シクロヘキサノン／メチルエチルケトン／メタノール／ブタノール（５５／２０／１０／５／５／５、質量部）
などを挙げることができる。 The non-chlorine-based organic solvent used in the present invention is more specifically described in JIII Journal of Technical Disclosure No. 2001-1745 (issued March 15, 2001, Invention Association) p. 12-16. Although the preferable combination of the said non-chlorine type | system | group organic solvent is mentioned below, it is not limited to these.
-Methyl acetate / acetone / methanol / ethanol / butanol (75/10/5/5/5, parts by mass),
-Methyl acetate / acetone / methanol / ethanol / propanol (75/10/5/5/5, parts by mass),
Methyl acetate / acetone / methanol / butanol / cyclohexane (75/10/5/5/5, parts by mass),
・ Methyl acetate / acetone / ethanol / butanol (81/8/7/4, parts by mass)
・ Methyl acetate / acetone / ethanol / butanol (82/10/4/4, parts by mass)
・ Methyl acetate / acetone / ethanol / butanol (80/10/4/6, part by mass)
Methyl acetate / methyl ethyl ketone / methanol / butanol (80/10/5/5, parts by mass),
-Methyl acetate / acetone / methyl ethyl ketone / ethanol / isopropanol (75/8/5/5/7, parts by mass)
-Methyl acetate / cyclopentanone / methanol / isopropanol (80/7/5/8, parts by mass),
-Methyl acetate / acetone / butanol (85/10/5, parts by mass),
Methyl acetate / cyclopentanone / acetone / methanol / butanol (60/15/14/5/6, parts by mass),
-Methyl acetate / cyclohexanone / methanol / hexane (70/20/5/5, parts by mass)
Methyl acetate / methyl ethyl ketone / acetone / methanol / ethanol (50/20/20/5/5, parts by mass),
Methyl acetate / 1,3-dioxolane / methanol / ethanol (70/20/5/5, parts by mass),
Methyl acetate / dioxane / acetone / methanol / ethanol (60/20/10/5/5, parts by mass),
Methyl acetate / acetone / cyclopentanone / ethanol / isobutanol / cyclohexane (65/10/10/5/5/5, parts by mass),
Methyl formate / methyl ethyl ketone / acetone / methanol / ethanol (50/20/20/5/5, parts by mass),
-Methyl formate / acetone / ethyl acetate / ethanol / butanol / hexane (65/10/10/5/5/5, parts by mass)
Acetone / methyl acetoacetate / methanol / ethanol (65/20/10/5, parts by mass)
Acetone / cyclopentanone / ethanol / butanol (65/20/10/5, parts by mass)
Acetone / 1,3-dioxolane / ethanol / butanol (65/20/10/5, parts by mass),
・ 1,3-Dioxolane / cyclohexanone / methyl ethyl ketone / methanol / butanol (55/20/10/5/5/5, parts by mass)
And so on.
　さらに、下記の方法で調製したセルロースエステル溶液を用いることもできる。
・酢酸メチル／アセトン／エタノール／ブタノール（８１／８／７／４、質量部）でセルロースエステル溶液を作製し濾過・濃縮後に２質量部のブタノールを追加添加する方法
・酢酸メチル／アセトン／エタノール／ブタノール（８４／１０／４／２、質量部）でセルロースエステル溶液を作製し濾過・濃縮後に４質量部のブタノールを追加添加する方法・酢酸メチル／アセトン／エタノール（８４／１０／６、質量部）でセルロースエステル溶液を作製し濾過・濃縮後に５質量部のブタノールを追加添加する方法
　本発明に用いるドープには、上記非塩素系有機溶媒以外に、ジクロロメタンを全有機溶媒量の１０質量％以下含有させてもよい。 Furthermore, the cellulose ester solution prepared by the following method can also be used.
A method of preparing a cellulose ester solution with methyl acetate / acetone / ethanol / butanol (81/8/7/4, parts by mass), adding 2 parts by weight of butanol after filtration and concentration, and methyl acetate / acetone / ethanol / A method of preparing a cellulose ester solution with butanol (84/10/4/2, parts by mass), adding 4 parts by weight of butanol after filtration and concentration, and methyl acetate / acetone / ethanol (84/10/6, parts by mass) ) And then adding 5 parts by weight of butanol after filtration and concentration In addition to the above non-chlorine organic solvent, dichloromethane is used in an amount of 10% by mass or less of the total organic solvent amount. You may make it contain.
　（セルロースエステル溶液特性）
　溶液流延製膜法により前記セルロースエステルフィルムを作製する場合は、用いるセルロースエステル溶液は、前記有機溶媒にセルロースエステルを１０～３０質量％の濃度で溶解させた溶液であるのが溶液流延製膜適性の点で好ましく、より好ましくは１３～２７質量％であり、特に好ましくは１５～２５質量％である。これらの濃度のセルロースエステル溶液は、セルロースエステルを所定の濃度になるように溶解して調製してもよいし、また予め低濃度溶液（例えば９～１４質量％）を調製した後に、後述する濃縮工程を経て、所定の高濃度の溶液としてもよい。さらに、予め高濃度のセルロースエステル溶液を調製した後に、種々の添加物を添加することで所定の低濃度のセルロースエステル溶液としてもよい。 (Characteristics of cellulose ester solution)
When the cellulose ester film is produced by the solution casting film forming method, the cellulose ester solution used is a solution obtained by dissolving cellulose ester in the organic solvent at a concentration of 10 to 30% by mass. It is preferable in terms of film suitability, more preferably 13 to 27% by mass, and particularly preferably 15 to 25% by mass. The cellulose ester solution having these concentrations may be prepared by dissolving the cellulose ester so as to have a predetermined concentration, or after preparing a low concentration solution (for example, 9 to 14% by mass) in advance, the concentration described later It is good also as a predetermined high concentration solution through a process. Furthermore, after preparing a high concentration cellulose ester solution in advance, a predetermined low concentration cellulose ester solution may be obtained by adding various additives.
　また、溶液流延製膜法により前記セルロースエステルフィルムを作製する場合は前記セルロースエステル溶液と同一組成の有機溶媒中にセルロースエステルを０．１～５質量％の濃度で溶解した希釈溶液中において、該セルロースエステルの会合体分子量が１５万～１５００万であることが、剥ぎ取り性を良くする点で好ましい。 Further, when the cellulose ester film is produced by a solution casting film forming method, in a diluted solution in which cellulose ester is dissolved at a concentration of 0.1 to 5% by mass in an organic solvent having the same composition as the cellulose ester solution, The molecular weight of the aggregate of the cellulose ester is preferably 150,000 to 15 million from the viewpoint of improving the peelability.
　さらに好ましくは、会合分子量が１８万～９００万である。この会合分子量は静的光散乱法で求めることができる。その際に同時に求められる慣性自乗半径は１０～２００ｎｍになるように溶解することが好ましい。 More preferably, the associated molecular weight is 180,000 to 9 million. This associated molecular weight can be determined by a static light scattering method. In this case, it is preferable that the inertial radius required simultaneously is dissolved so as to be 10 to 200 nm.
　さらに好ましい慣性自乗半径は２０～２００ｎｍである。さらにまた、第２ビリアル係数が－２×１０－４～＋４×１０－４となるように溶解することが好ましく、より好ましくは第２ビリアル係数が－２×１０－４～＋２×１０－４である。 A more preferable inertial square radius is 20 to 200 nm. Furthermore, it is preferable to dissolve so that the second virial coefficient is −2 × 10 −4 to + 4 × 10 −4, and more preferably, the second virial coefficient is −2 × 10 −4 to + 2 × 10 −4. It is.
　ここで、会合分子量、さらに慣性自乗半径及び第２ビリアル係数の定義について述べる。これらは下記方法に従って、静的光散乱法を用いて測定する。 Here, we will describe the association molecular weight, the inertial square radius, and the definition of the second virial coefficient. These are measured using the static light scattering method according to the following method.
　測定は、装置の都合上希薄領域で測定するが、これらの測定値は高濃度域でのドープの挙動を反映するものである。 The measurement is performed in a dilute region for the convenience of the apparatus, but these measured values reflect the behavior of the dope in the high concentration region.
　まず、セルロースエステルをドープに使用する溶剤に溶かし、０．１質量％、０．２質量％、０．３質量％、０．４質量％の溶液を調製する。 First, the cellulose ester is dissolved in a solvent used for the dope to prepare 0.1% by mass, 0.2% by mass, 0.3% by mass, and 0.4% by mass solution.
　なお、秤量は吸湿を防ぐためセルロースエステルは１２０℃で２時間乾燥したものを用い、２５℃，１０％ＲＨで行う。溶解方法は、ドープ溶解時に採用した方法（常温溶解法、冷却溶解法、高温溶解法）に従って実施する。 In order to prevent moisture absorption, the cellulose ester is dried at 120 ° C. for 2 hours and is measured at 25 ° C. and 10% RH. The dissolution method is carried out according to the method employed at the time of dope dissolution (room temperature dissolution method, cooling dissolution method, high temperature dissolution method).
　続いてこれらの溶液、及び溶剤を０．２μｍのテトラフルオロエチレン製（デュポン（株）製）フィルターで濾過する。そして、ろ過した溶液を静的光散乱を、光散乱測定装置（大塚電子（株）製ＤＬＳ－７００）を用い、２５℃に於いて３０度から１４０度まで１０度間隔で測定する。 Subsequently, these solution and solvent are filtered through a 0.2 μm tetrafluoroethylene (DuPont) filter. Then, the static light scattering of the filtered solution is measured at 10 ° intervals from 30 ° to 140 ° at 25 ° C. using a light scattering measuring device (DLS-700 manufactured by Otsuka Electronics Co., Ltd.).
　得られたデータをＢＥＲＲＹプロット法にて解析する。なお、この解析に必要な屈折率はアッベ屈折系で求めた溶剤の値を用い、屈折率の濃度勾配（ｄｎ／ｄｃ）は、示差屈折計（大塚電子（株）製ＤＲＭ－１０２１）を用い、光散乱測定に用いた溶剤、溶液を用いて測定する。 ・ Analyze the obtained data by the BERRY plot method. The refractive index necessary for this analysis is the value of the solvent obtained by the Abbe refracting system, and the refractive index concentration gradient (dn / dc) is determined using a differential refractometer (DRM-1021 manufactured by Otsuka Electronics Co., Ltd.). Measure using the solvent and solution used for light scattering measurement.
　（ドープ調製）
　次に、セルロースエステル溶液（ドープ）の調製について述べる。セルロースエステルの溶解方法は特に限定されず、室温でもよくさらには冷却溶解法あるいは高温溶解方法、さらにはこれらの組み合わせで実施される。 (Dope preparation)
Next, preparation of a cellulose ester solution (dope) will be described. The method for dissolving the cellulose ester is not particularly limited, and may be room temperature, and further, a cooling dissolution method or a high temperature dissolution method, and further a combination thereof.
　これらに関しては、例えば特開平５－１６３３０１号、特開昭６１－１０６６２８号、特開昭５８－１２７７３７号、特開平９－９５５４４号、特開平１０－９５８５４号、特開平１０－４５９５０号、特開２０００－５３７８４号、特開平１１－３２２９４６号、さらに特開平１１－３２２９４７号、特開平２－２７６８３０号、特開２０００－２７３２３９号、特開平１１－７１４６３号、特開平０４－２５９５１１号、特開２０００－２７３１８４号、特開平１１－３２３０１７号、特開平１１－３０２３８８号各公報などにセルロースエステル溶液の調製法が記載されている。 Regarding these, for example, JP-A-5-163301, JP-A-61-106628, JP-A-58-127737, JP-A-9-95544, JP-A-10-95854, JP-A-10-45950, JP 2000-53784, JP 11-322946, JP 11-322947, JP 2-276830, JP 2000-273239, JP 11-71463, JP 04-259511, Special JP-A-2000-273184, JP-A-11-323017, JP-A-11-302388, etc. describe methods for preparing cellulose ester solutions.
　以上記載したこれらのセルロースエステルの有機溶媒への溶解方法は、本発明においても適宜本発明の範囲であればこれらの技術を適用できるものである。 The above-described method for dissolving these cellulose esters in an organic solvent is applicable to the present invention as long as it is within the scope of the present invention.
　これらの詳細は、特に非塩素系溶媒系については発明協会公開技報公技番号２００１－１７４５号（２００１年３月１５日発行、発明協会）ｐ．２２－２５に詳細に記載されている方法で実施される。 These details, especially for non-chlorinated solvent systems, are disclosed in the Japan Society for Invention and Innovation Technical Bulletin No. 2001-1745 (issued March 15, 2001, Invention Association) p. It is carried out in the manner described in detail in 22-25.
　さらに、本発明に係るセルロースエステルのドープ溶液は、溶液濃縮、濾過が通常実施され、同様に発明協会公開技報公技番号２００１－１７４５号（２００１年３月１５日発行、発明協会）ｐ．２５に詳細に記載されている。 Further, the cellulose ester dope solution according to the present invention is usually subjected to solution concentration and filtration. Similarly, the Japan Institute of Invention and Innovation Technical Bulletin No. 2001-1745 (issued March 15, 2001, Invention Association) p. 25 in detail.
　なお、高温度で溶解する場合は、使用する有機溶媒の沸点以上の場合がほとんどであり、その場合は加圧状態で用いられる。 In addition, when it melt | dissolves at high temperature, it is the case where it is more than the boiling point of the organic solvent to be used, and in that case, it uses in a pressurized state.
　セルロースエステル溶液は、その溶液の粘度と動的貯蔵弾性率が以下に述べる範囲であることが、流延しやすく好ましい。試料溶液１ｍｌをレオメーター（ＣＬＳ　５００）に直径４ｃｍ／２°のＳｔｅｅｌ　Ｃｏｎｅ（共にＴＡ　Ｉｎｓｔｒｕｍｅｎｔｓ社製）を用いて測定する。 The cellulose ester solution preferably has a viscosity and a dynamic storage elastic modulus within the ranges described below because it is easy to cast. 1 ml of the sample solution is measured on a rheometer (CLS 500) using a Steel Cone (both manufactured by TA Instruments) having a diameter of 4 cm / 2 °.
　測定条件は、Ｏｓｃｉｌｌａｔｉｏｎ　Ｓｔｅｐ／Ｔｅｍｐｅｒａｔｕｒｅ　Ｒａｍｐで４０℃～－１０℃の範囲を２℃／分で可変して測定し、４０℃の静的非ニュートン粘度ｎ＊（Ｐａ・ｓ）及び５℃の貯蔵弾性率Ｇ’（Ｐａ）を求める。 Measurement conditions were measured by varying the range from 40 ° C. to −10 ° C. at 2 ° C./min with Oscillation Step / Temperature Ramp, static non-Newtonian viscosity n * (Pa · s) at 40 ° C. and storage at 5 ° C. The elastic modulus G ′ (Pa) is obtained.
　なお、試料溶液は予め測定開始温度にて液温一定となるまで保温した後に測定を開始する。本発明では、４０℃での粘度が１～４００Ｐａ・ｓであり、１５℃での動的貯蔵弾性率が５００Ｐａ以上であるのが好ましく、より好ましくは４０℃での粘度が１０～２００Ｐａ・ｓで、１５℃での動的貯蔵弾性率が１００～１００万である。 Note that the sample solution is kept at the measurement start temperature until the liquid temperature becomes constant, and then the measurement is started. In the present invention, the viscosity at 40 ° C. is 1 to 400 Pa · s, the dynamic storage elastic modulus at 15 ° C. is preferably 500 Pa or more, and more preferably the viscosity at 40 ° C. is 10 to 200 Pa · s. Thus, the dynamic storage modulus at 15 ° C. is 1 to 1 million.
　さらには、低温での動的貯蔵弾性率が大きいほど好ましく、例えば流延支持体が－５℃の場合は動的貯蔵弾性率が－５℃で１万～１００万Ｐａであることが好ましく、支持体が－５０℃の場合は－５０℃での動的貯蔵弾性率が１万～５００万Ｐａが好ましい。 Furthermore, it is preferable that the dynamic storage elastic modulus at low temperature is large. For example, when the casting support is −5 ° C., the dynamic storage elastic modulus is preferably 10,000 to 1,000,000 Pa at −5 ° C. When the support is at −50 ° C., the dynamic storage elastic modulus at −50 ° C. is preferably 10,000 to 5 million Pa.
　本発明においては、前述の特定のセルロースエステルを用いているので、高濃度のドープが得られるのが特徴であり、濃縮という手段に頼らずとも高濃度でしかも安定性の優れたセルロースエステル溶液が得られる。 In the present invention, since the above-mentioned specific cellulose ester is used, it is characterized in that a high concentration dope is obtained, and a cellulose ester solution having a high concentration and excellent stability can be obtained without relying on a means of concentration. can get.
　さらに溶解し易くするために低い濃度で溶解してから、濃縮手段を用いて濃縮してもよい。 In order to make it easier to dissolve, it may be dissolved at a low concentration and then concentrated using a concentration means.
　濃縮の方法としては、特に限定するものはないが、例えば、低濃度溶液を筒体とその内部の周方向に回転する回転羽根外周の回転軌跡との間に導くとともに、溶液との間に温度差を与えて溶媒を蒸発させながら高濃度溶液を得る方法（例えば、特開平４－２５９５１１号公報等）、加熱した低濃度溶液をノズルから容器内に吹き込み、溶液をノズルから容器内壁に当たるまでの間で溶媒をフラッシュ蒸発させるとともに、溶媒蒸気を容器から抜き出し、高濃度溶液を容器底から抜き出す方法（例えば、米国特許第２，５４１，０１２号、米国特許第２，８５８，２２９号、米国特許第４，４１４，３４１号、米国特許第４，５０４，３５５号各明細書等などに記載の方法）等で実施できる。 The concentration method is not particularly limited. For example, the low-concentration solution is guided between the cylindrical body and the rotation trajectory of the outer periphery of the rotating blade rotating in the circumferential direction, and the temperature between the solution and the solution. A method for obtaining a high-concentration solution while evaporating the solvent by giving a difference (for example, Japanese Patent Laid-Open No. 4-259511), blowing a heated low-concentration solution into the container from the nozzle, and until the solution hits the inner wall of the container from the nozzle In which the solvent is flash evaporated and the solvent vapor is withdrawn from the container and the concentrated solution is withdrawn from the bottom of the container (eg, US Pat. No. 2,541,012, US Pat. No. 2,858,229, US Pat. No. 4,414,341, US Pat. No. 4,504,355, etc.).
　溶液は流延に先だって金網やネルなどの適当な濾材を用いて、未溶解物やゴミ、不純物などの異物を濾過除去しておくのが好ましい。 Prior to casting, it is preferable to filter off foreign matters such as undissolved matter, dust, and impurities using a suitable filter medium such as a wire mesh or flannel.
　セルロースエステル溶液の濾過には絶対濾過精度が０．１～１００μｍのフィルターを用いることが好ましく、さらには絶対濾過精度が０．５～２５μｍであるフィルターを用いることが好ましい。 For the filtration of the cellulose ester solution, it is preferable to use a filter having an absolute filtration accuracy of 0.1 to 100 μm, and it is more preferable to use a filter having an absolute filtration accuracy of 0.5 to 25 μm.
　フィルターの厚さは、０．１～１０ｍｍが好ましく、さらには０．２～２ｍｍが好ましい。その場合、濾過圧力は１．６ＭＰａ以下が好ましく、より好ましくは１．２ＭＰａ以下、さらには１．０ＭＰａ以下、特に０．２ＭＰａ以下で濾過することが好ましい。 The thickness of the filter is preferably 0.1 to 10 mm, more preferably 0.2 to 2 mm. In that case, the filtration pressure is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, further 1.0 MPa or less, and particularly preferably 0.2 MPa or less.
　濾材としては、ガラス繊維、セルロース繊維、濾紙、四フッ化エチレン樹脂などのフッ素樹脂等の従来公知である材料を好ましく用いることができ、特にセラミックス、金属等が好ましく用いられる。セルロースエステル溶液の製膜直前の粘度は、製膜の際に流延可能な範囲であればよく、通常１０Ｐａ・ｓ～２０００Ｐａ・ｓの範囲に調製されることが好ましく、３０Ｐａ・ｓ～１０００Ｐａ・ｓがより好ましく、４０Ｐａ・ｓ～５００Ｐａ・ｓがさらに好ましい。 As the filter medium, conventionally known materials such as glass fibers, cellulose fibers, filter paper, fluororesins such as tetrafluoroethylene resin can be preferably used, and ceramics, metals and the like are particularly preferably used. The viscosity of the cellulose ester solution immediately before film formation may be in a range that allows casting, and is usually adjusted to a range of 10 Pa · s to 2000 Pa · s, preferably 30 Pa · s to 1000 Pa · s. s is more preferable, and 40 Pa · s to 500 Pa · s is more preferable.
　なお、この時の温度はその流延時の温度であれば特に限定されないが、好ましくは－５～＋７０℃であり、より好ましくは－５～＋５５℃である。 The temperature at this time is not particularly limited as long as it is a temperature at the time of casting, but is preferably −5 to + 70 ° C., more preferably −5 to + 55 ° C.
　（製膜）
　本発明に係るセルロースエステルフィルムは、前記セルロースエステル溶液を用いて製膜を行うことにより得ることができる。 (Film formation)
The cellulose ester film according to the present invention can be obtained by forming a film using the cellulose ester solution.
　製膜方法及び設備は、従来セルローストリアセテートフィルム製造に供する溶液流延製膜装置が用いられる。 As a film forming method and equipment, a solution casting film forming apparatus conventionally used for producing a cellulose triacetate film is used.
　溶解機（釜）から調製されたドープ（セルロースエステル溶液）を貯蔵釜で一旦貯蔵し、ドープに含まれている泡を脱泡して最終調製をする。 The dope (cellulose ester solution) prepared from the dissolving machine (kettle) is temporarily stored in a storage kettle, and the foam contained in the dope is defoamed for final preparation.
　ドープをドープ排出口から、例えば回転数によって高精度に定量送液できる加圧型定量ギヤポンプを通して加圧型ダイに送り、ドープを加圧型ダイの口金（スリット）からエンドレスに走行している流延部の金属支持体の上に均一に流延され、金属支持体がほぼ一周した剥離点で、生乾きのドープ膜（ウェブとも呼ぶ）を金属支持体から剥離する。 The dope is sent from the dope discharge port to the pressure die through a pressure metering gear pump capable of delivering a constant amount of liquid with high accuracy, for example, by the number of rotations, and the dope is run endlessly from the die (slit) of the pressure die. The dry-dried dope film (also referred to as web) is peeled off from the metal support at a peeling point that is uniformly cast on the metal support and substantially rounds the metal support.
　得られるウェブの両端をクリップで挟み、幅保持しながらテンターで搬送して乾燥し、続いて乾燥装置のロール群で搬送し乾燥を終了して巻き取り機で所定の長さに巻き取る。 The both ends of the obtained web are sandwiched between clips, transported by a tenter while holding the width, dried, then transported by a roll group of a drying device, dried, and wound up to a predetermined length by a winder.
　テンターとロール群の乾燥装置との組み合わせはその目的により変わる。電子ディスプレイ用機能性保護膜に用いる溶液流延製膜方法においては、溶液流延製膜装置の他に、下引層、帯電防止層、ハレーション防止層、保護層等のフィルムへの表面加工のために、塗布装置が付加されることが多い。以下に各製造工程について簡単に述べるが、これらに限定されるものではない。 The combination of a tenter and a roll group dryer varies depending on the purpose. In the solution casting film forming method used for the functional protective film for electronic displays, in addition to the solution casting film forming apparatus, surface processing on films such as an undercoat layer, an antistatic layer, an antihalation layer, a protective layer, etc. Therefore, a coating device is often added. Although each manufacturing process is described briefly below, it is not limited to these.
　まず、調製したセルロースエステル溶液（ドープ）は、溶液流延製膜法によりセルロースエステルフィルムを作製する際に、ドープをドラム又はバンド上に流延し、溶媒を蒸発させてフィルムを形成する。 First, the prepared cellulose ester solution (dope) is formed by casting the dope on a drum or a band and evaporating the solvent when producing a cellulose ester film by a solution casting film forming method.
　流延前のドープは、固形分量が５～４０質量％となるように濃度を調整することが好ましい。ドラム又はバンドの表面は、鏡面状態に仕上げておくことが好ましい。ドープは、表面温度が３０℃以下のドラム又はバンド上に流延することが好ましく用いられ、特には－１０～２０℃の金属支持体温度であることが好ましい。 The concentration of the dope before casting is preferably adjusted so that the solid content is 5 to 40% by mass. The surface of the drum or band is preferably finished in a mirror state. The dope is preferably cast on a drum or band having a surface temperature of 30 ° C. or less, and particularly preferably a metal support temperature of −10 to 20 ° C.
　さらに特開２０００－３０１５５５号、特開２０００－３０１５５８号、特開平０７－０３２３９１号、特開平０３－１９３３１６号、特開平０５－０８６２１２号、特開昭６２－０３７１１３号、特開平０２－２７６６０７号、特開昭５５－０１４２０１号、特開平０２－１１１５１１号、及び特開平０２－２０８６５０号の各公報に記載の方法を本発明では用いることができる。 Further, JP 2000-301555, JP 2000-301558, JP 07-032391, JP 03-193316, JP 05-086212, JP 62-037113, JP 02-276607. The methods described in JP-A Nos. 55-014201, 02-111511, and 02-208650 can be used in the present invention.
　（重層流延）
　セルロースエステル溶液を、金属支持体としての平滑なバンド上或いはドラム上に単層液として流延してもよいし、２層以上の複数のセルロースエステル液を流延してもよい。 (Multilayer casting)
The cellulose ester solution may be cast as a single layer liquid on a smooth band or drum as a metal support, or a plurality of cellulose ester liquids of two or more layers may be cast.
　複数のセルロースエステル溶液を流延する場合、金属支持体の進行方向に間隔を置いて設けた複数の流延口からセルロースエステルを含む溶液をそれぞれ流延させて積層させながらフィルムを作製してもよく、例えば特開昭６１－１５８４１４号、特開平１－１２２４１９号、及び特開平１１－１９８２８５号の各公報などに記載の方法が適応できる。また、２つの流延口からセルロースエステル溶液を流延することによってフィルム化することでもよく、例えば特公昭６０－２７５６２号、特開昭６１－９４７２４号、特開昭６１－９４７２４５号、特開昭６１－１０４８１３号、特開昭６１－１５８４１３号、及び特開平６－１３４９３３号の各公報に記載の方法で実施できる。 When casting a plurality of cellulose ester solutions, even if a film is produced while casting and laminating a solution containing a cellulose ester from a plurality of casting openings provided at intervals in the traveling direction of the metal support, For example, the methods described in JP-A-61-158414, JP-A-1-122419, and JP-A-11-198285 can be applied. Alternatively, a film may be formed by casting a cellulose ester solution from two casting ports. For example, JP-B-60-27562, JP-A-61-94724, JP-A-61-947245, JP-A-6-947245 It can be carried out by the methods described in JP-A-61-104813, JP-A-61-158413, and JP-A-6-134933.
　また、特開昭５６－１６２６１７号公報に記載の高粘度セルロースエステル溶液の流れを低粘度のセルロースエステル溶液で包み込み、その高、低粘度のセルロースエステル溶液を同時に押出すセルロースエステルフィルム流延方法でもよい。さらに又、特開昭６１－９４７２４号及び特開昭６１－９４７２５号の各公報に記載の外側の溶液が内側の溶液よりも貧溶媒であるアルコール成分を多く含有させることも好ましい態様である。 Also, a cellulose ester film casting method described in Japanese Patent Application Laid-Open No. 56-162617 is a method of wrapping a flow of a high viscosity cellulose ester solution with a low viscosity cellulose ester solution and simultaneously extruding the high and low viscosity cellulose ester solution. Good. Furthermore, it is also a preferable embodiment that the outer solution described in JP-A-61-94724 and JP-A-61-94725 contains a larger amount of an alcohol component which is a poor solvent than the inner solution.
　或いは、また２個の流延口を用いて、第一の流延口により金属支持体に成型したフィルムを剥離し、金属支持体面に接していた側に第二の流延を行うことでより、フィルムを作製することでもよく、例えば特公昭４４－２０２３５号公報に記載されている方法である。 Alternatively, by using two casting ports, the film cast on the metal support is peeled off by the first casting port, and the second casting is performed on the side in contact with the metal support surface. Alternatively, a film may be produced, for example, a method described in Japanese Patent Publication No. 44-20235.
　流延するセルロースエステル溶液は同一の溶液でもよいし、異なるセルロースエステル溶液でもよく特に限定されない。複数のセルロースエステル層に機能を持たせるために、その機能に応じたセルロースエステル溶液を、それぞれの流延口から押出せばよい。 The cellulose ester solution to be cast may be the same solution or different cellulose ester solutions, and is not particularly limited. In order to give a function to a plurality of cellulose ester layers, a cellulose ester solution corresponding to the function may be extruded from each casting port.
　さらにセルロースエステル溶液は、他の機能層（例えば、接着層、染料層、帯電防止層、アンチハレーション層、ＵＶ吸収層、偏光子など）を同時に流延することも実施しうる。 Further, the cellulose ester solution may be cast simultaneously with other functional layers (for example, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer, a UV absorption layer, and a polarizer).
　従来の単層液では、必要なフィルム厚さにするためには高濃度で高粘度のセルロースエステル溶液を押出すことが必要であり、その場合セルロースエステル溶液の安定性が悪くて固形物が発生し、ブツ故障となったり、平面性が不良であったりして問題となることが多かった。 In conventional single-layer liquids, it is necessary to extrude a high-concentration and high-viscosity cellulose ester solution to obtain the required film thickness. In this case, the stability of the cellulose ester solution is poor and solids are generated. In many cases, however, it becomes a problem due to a failure or poor flatness.
　この解決として、複数のセルロースエステル溶液を流延口から流延することにより、高粘度の溶液を同時に金属支持体上に押出すことができ、平面性も良化し優れた面状のフィルムが作製できるばかりでなく、濃厚なセルロースエステル溶液を用いることで乾燥負荷の低減化が達成でき、フィルムの生産スピードを高めることができる。 As a solution to this, by casting multiple cellulose ester solutions from the casting port, a highly viscous solution can be extruded onto a metal support at the same time. Not only can the drying load be reduced by using a concentrated cellulose ester solution, but the production speed of the film can be increased.
　共流延の場合、内側と外側の厚さは特に限定されないが、好ましくは外側が全膜厚の１～５０％であることが好ましく、より好ましくは２～３０％の厚さである。 In the case of co-casting, the inner and outer thicknesses are not particularly limited, but the outer side is preferably 1 to 50% of the total film thickness, more preferably 2 to 30%.
　ここで、三層以上の共流延の場合は金属支持体に接した層と空気側に接した層のトータル膜厚を外側の厚さと定義する。共流延の場合、前述の可塑剤、紫外線吸収剤、マット剤等の添加物濃度が異なるセルロースエステル溶液を共流延して、積層構造のセルロースエステルフィルムを作製することもできる。 Here, in the case of co-casting with three or more layers, the total thickness of the layer in contact with the metal support and the layer in contact with the air side is defined as the outer thickness. In the case of co-casting, a cellulose ester film having a laminated structure can be produced by co-casting cellulose ester solutions having different additive concentrations such as the above-mentioned plasticizer, ultraviolet absorber and matting agent.
　例えば、スキン層／コア層／スキン層といった構成のセルロースエステルフィルムを作ることができる。例えば、マット剤は、スキン層に多く、又はスキン層のみに入れることができる。 For example, a cellulose ester film having a structure of skin layer / core layer / skin layer can be produced. For example, the matting agent can be contained in the skin layer in a large amount or only in the skin layer.
　可塑剤、紫外線吸収剤はスキン層よりもコア層に多くいれることができ、コア層のみにいれてもよい。 The plasticizer and the UV absorber can be contained in the core layer more than the skin layer, and may be contained only in the core layer.
　また、コア層とスキン層で可塑剤、紫外線吸収剤の種類を変更することもでき、例えばスキン層に低揮発性の可塑剤及び紫外線吸収剤の少なくともいずれかを含ませ、コア層に可塑性に優れた可塑剤、或いは紫外線吸収性に優れた紫外線吸収剤を添加することもできる。 In addition, the type of plasticizer and ultraviolet absorber can be changed between the core layer and the skin layer. For example, at least one of a low-volatile plasticizer and an ultraviolet absorber is included in the skin layer, and the core layer is made plastic. It is also possible to add an excellent plasticizer or an ultraviolet absorber excellent in ultraviolet absorption.
　また、剥離促進剤を金属支持体側のスキン層のみ含有させることも好ましい態様である。また、冷却ドラム法で金属支持体を冷却して溶液をゲル化させるために、スキン層に貧溶媒であるアルコールをコア層より多く添加することも好ましい。スキン層とコア層のＴｇが異なっていてもよく、スキン層のＴｇよりコア層のＴｇが低いことが好ましい。 In addition, it is also a preferred embodiment that a peeling accelerator is contained only in the skin layer on the metal support side. It is also preferable to add more alcohol, which is a poor solvent, to the skin layer than the core layer in order to cool the metal support by the cooling drum method to gel the solution. The Tg of the skin layer and the core layer may be different, and the Tg of the core layer is preferably lower than the Tg of the skin layer.
　また、流延時のセルロースエステルを含む溶液の粘度もスキン層とコア層で異なっていてもよく、スキン層の粘度がコア層の粘度よりも小さいことが好ましいが、コア層の粘度がスキン層の粘度より小さくてもよい。 Further, the viscosity of the solution containing the cellulose ester at the time of casting may be different between the skin layer and the core layer, and the viscosity of the skin layer is preferably smaller than the viscosity of the core layer. It may be smaller than the viscosity.
　（流延）
　溶液の流延方法としては、調製されたドープを加圧ダイから金属支持体上に均一に押し出す方法、一旦金属支持体上に流延されたドープをブレードで膜厚を調節するドクターブレードによる方法、或いは逆回転するロールで調節するリバースロールコーターによる方法等があるが、加圧ダイによる方法が好ましい。 (Casting)
As a solution casting method, a method in which the prepared dope is uniformly extruded from a pressure die onto a metal support, and a method using a doctor blade in which the dope once cast on the metal support is adjusted with a blade is used. Alternatively, there is a method using a reverse roll coater that adjusts with a reverse rotating roll, and a method using a pressure die is preferable.
　加圧ダイにはコートハンガータイプやＴダイタイプ等があるがいずれも好ましく用いることができる。また、ここで挙げた方法以外にも従来知られているセルローストリアセテート溶液を溶液流延製膜する種々の方法で実施でき、用いる溶媒の沸点等の違いを考慮して各条件を設定することによりそれぞれの公報に記載の内容と同様の効果が得られる。本発明に係るセルロースエステルフィルムを製造するのに使用されるエンドレスに走行する金属支持体としては、表面がクロムメッキによって鏡面仕上げされたドラムや表面研磨によって鏡面仕上げされたステンレスベルト（バンドといってもよい）が用いられる。 There are coat hanger type and T die type for the pressure die, and any of them can be used preferably. In addition to the methods listed here, it can be carried out by various methods for casting a cellulose triacetate solution known in the art, and by setting each condition in consideration of differences in the boiling point of the solvent used, etc. The same effects as described in the respective publications can be obtained. The endlessly running metal support used to manufacture the cellulose ester film according to the present invention includes a drum whose surface is mirror-finished by chrome plating and a stainless steel belt (which is called a band) whose surface is mirror-finished by surface polishing. May be used).
　本発明に係るセルロースエステルフィルムの製造に用いられる加圧ダイは、金属支持体の上方に１基或いは２基以上の設置でもよい。 The pressure die used for the production of the cellulose ester film according to the present invention may be one or two or more installed above the metal support.
　好ましくは１基又は２基である。２基以上設置する場合には流延するドープ量をそれぞれのダイに種々な割合にわけてもよく、複数の精密定量ギヤアポンプからそれぞれの割合でダイにドープを送液してもよい。 Preferably 1 or 2 groups. When two or more units are installed, the amount of dope to be cast may be divided into various ratios for each die, or the dope may be fed to the dies from each of a plurality of precision quantitative gear pumps.
　流延に用いられるセルロースエステル溶液の温度は、－１０～５５℃が好ましくより好ましくは２５～５０℃である。その場合、工程のすべてが同一でもよく、あるいは工程の各所で異なっていてもよい。異なる場合は、流延直前で所望の温度であればよい。 The temperature of the cellulose ester solution used for casting is preferably −10 to 55 ° C., more preferably 25 to 50 ° C. In that case, all of the steps may be the same or may be different at different points in the step. If they are different, the temperature may be a desired temperature just before casting.
　（乾燥）
　セルロースエステルフィルムの製造に係わる金属支持体上におけるドープの乾燥は、一般的には金属支持体（ドラム或いはベルト）の表面側、つまり金属支持体上にあるウェブの表面から熱風を当てる方法、ドラム或いはベルトの裏面から熱風を当てる方法、温度コントロールした液体をベルトやドラムのドープ流延面の反対側である裏面から接触させて、伝熱によりドラム或いはベルトを加熱し表面温度をコントロールする液体伝熱方法などがあるが、裏面液体伝熱方式が好ましい。 (Dry)
The dope drying on the metal support involved in the production of the cellulose ester film is generally performed by applying hot air from the surface side of the metal support (drum or belt), that is, the surface of the web on the metal support, drum Alternatively, a method in which hot air is applied from the back of the belt, a liquid whose temperature is controlled is brought into contact with the back of the belt or drum opposite the dope casting surface, and the drum or belt is heated by heat transfer to control the surface temperature. Although there is a heat method, the back surface liquid heat transfer method is preferable.
　流延される前の金属支持体の表面温度はドープに用いられている溶媒の沸点以下であれば何度でもよい。 The surface temperature of the metal support before casting may be any number as long as it is not higher than the boiling point of the solvent used for the dope.
　しかし、乾燥を促進するためには、また金属支持体上での流動性を失わせるためには、使用される溶媒の内の最も沸点の低い溶媒の沸点より１～１０℃低い温度に設定することが好ましい。尚、流延ドープを冷却して乾燥することなく剥ぎ取る場合はこの限りではない。 However, in order to accelerate drying and to lose fluidity on the metal support, the temperature is set to 1 to 10 ° C. lower than the boiling point of the lowest boiling solvent among the solvents used. It is preferable. This is not the case when the casting dope is cooled and peeled off without drying.
　（延伸処理）
　本発明に係るセルロースエステルフィルムは、延伸処理によりリターデーションを調整することができる。 (Extension process)
The retardation of the cellulose ester film according to the present invention can be adjusted by a stretching treatment.
　さらには、積極的に幅方向に延伸する方法もあり、例えば、特開昭６２－１１５０３５号、特開平４－１５２１２５号、特開平４－２８４２１１号、特開平４－２９８３１０号、及び特開平１１－４８２７１号の各公報などに記載されている。 Furthermore, there is also a method of positively stretching in the width direction, for example, JP-A-62-115035, JP-A-4-152125, JP-A-4-284221, JP-A-4-298310, and JP-A-11-298310. -48271 and the like.
　これは、セルロースエステルフィルムの面内リターデーション値を高い値とするために、製造したフィルムを延伸する。 This is to stretch the produced film in order to increase the in-plane retardation value of the cellulose ester film.
　フィルムの延伸は、常温又は加熱条件下で実施する。加熱温度は、フィルムのガラス転移温度以下であることが好ましい。フィルムの延伸は、縦あるいは横だけの一軸延伸でもよく同時あるいは逐次２軸延伸でもよい。延伸は１～２００％の延伸が行われる。 The film is stretched at room temperature or under heating conditions. The heating temperature is preferably not higher than the glass transition temperature of the film. The stretching of the film may be uniaxial stretching only in the longitudinal or lateral direction, or may be simultaneous or sequential biaxial stretching. Stretching is performed at 1 to 200%.
　好ましくは１～１００％の延伸が、特に好ましくは１から５０％延伸を行う。光学フィルムの複屈折は幅方向の屈折率が長さ方向の屈折率よりも大きくなることが好ましい。従って幅方向により多く延伸することが好ましい。 The stretching is preferably 1 to 100%, particularly preferably 1 to 50%. The birefringence of the optical film is preferably such that the refractive index in the width direction is larger than the refractive index in the length direction. Therefore, it is preferable to stretch more in the width direction.
　また、延伸処理は製膜工程の途中で行ってもよいし、製膜して巻き取った原反を延伸処理してもよい。前者の場合には残留溶剤量を含んだ状態で延伸を行ってもよく、残留溶剤量が２～３０％で好ましく延伸することができる。 In addition, the stretching process may be performed in the middle of the film forming process, or the raw film that has been formed and wound may be stretched. In the former case, the stretching may be performed in a state including the residual solvent amount, and the stretching can be preferably performed with the residual solvent amount of 2 to 30%.
　乾燥後得られる本発明に係るセルロースエステルフィルムの膜厚は、使用目的によって異なるが、本発明の効果を得るためには２０～５０μｍであることが好ましい。 The film thickness of the cellulose ester film according to the present invention obtained after drying varies depending on the purpose of use, but is preferably 20 to 50 μm in order to obtain the effects of the present invention.
　フィルム厚さの調製は、所望の厚さになるように、ドープ中に含まれる固形分濃度、ダイの口金のスリット間隙、ダイからの押し出し圧力、金属支持体速度等を調節すればよい。 The thickness of the film may be adjusted by adjusting the solid content concentration contained in the dope, the slit gap of the die base, the extrusion pressure from the die, the metal support speed, and the like.
　以上のようにして得られたセルロースエステルフィルムの幅は０．５～３ｍが好ましく、より好ましくは０．６～２．５ｍ、さらに好ましくは０．８～２．２ｍである。長さは１ロールあたり１００～１００００ｍで巻き取るのが好ましく、より好ましくは５００～７０００ｍであり、さらに好ましくは１０００～６０００ｍである。 The width of the cellulose ester film obtained as described above is preferably 0.5 to 3 m, more preferably 0.6 to 2.5 m, and still more preferably 0.8 to 2.2 m. The length is preferably 100 to 10,000 m per roll, more preferably 500 to 7000 m, and still more preferably 1000 to 6000 m.
　巻き取る際、少なくとも片端にナーリングを付与するのが好ましく、幅は３ｍｍ～５０ｍｍが好ましく、より好ましくは５ｍｍ～３０ｍｍ、高さは０．５～５００μｍが好ましく、より好ましくは１～２００μｍである。これは片押しであっても両押しであってもよい。 When winding, knurling is preferably applied to at least one end, the width is preferably 3 mm to 50 mm, more preferably 5 mm to 30 mm, and the height is preferably 0.5 to 500 μm, more preferably 1 to 200 μm. This may be a single push or a double push.
　全幅のＲｏ（５９０）値のばらつきが±５ｎｍであることが好ましく、±３ｎｍであることがさらに好ましい。また、Ｒｔ（５９０）値のバラツキは±１０ｎｍが好ましく、±５ｎｍであることがさらに好ましい。また、長さ方向のＲｏ値、及びＲｔ値のバラツキも幅方向のバラツキの範囲内であることが好ましい。 The variation of the Ro (590) value of the full width is preferably ± 5 nm, more preferably ± 3 nm. Further, the variation of the Rt (590) value is preferably ± 10 nm, and more preferably ± 5 nm. Moreover, it is preferable that the variation in the Ro value and the Rt value in the length direction is also within the range of the variation in the width direction.
　（セルロースエステルフィルムの光学特性）
　前記第２光学異方性層に用いられるセルロースエステルフィルムは、所定の光学特性を有する第１光学異方性層と組み合わされて、液晶表示装置、特にＩＰＳモード液晶表示装置の視野角を広くするのに寄与するため、以下の関係式（Ｉ）～（III）を満たすことを要する。
関係式（Ｉ）：ｎｘ＞ｎｙ＞ｎｚ
関係式（II）：２０ｎｍ≦Ｒｏ（２）（５９０ｎｍ）≦１５０ｎｍ、
関係式（III）：１００ｎｍ≦Ｒｔ（２）（５９０ｎｍ）≦３００ｎｍ
〔但し、第１光学異方性層及び第２光学異方性層の屈折率は、以下のｎｘ、ｎｙ、ｎｚで定義され、
Ｒｏ（１）＝（ｎｘ－ｎｙ）×ｄ
Ｒｔ（１）＝（（ｎｘ＋ｎｙ）／２－ｎｚ）×ｄ、
及び
Ｒｏ（２）＝（ｎｘ－ｎｙ）×ｄ
Ｒｔ（２）＝（（ｎｘ＋ｎｙ）／２－ｎｚ）×ｄ
で示される。
（式中、ｎｘは光学異方性層の面内の幅手方向の屈折率を、ｎｙは光学異方性層の面内で製膜又は搬送方向でありｎｘと面内で直交する方向の屈折率を、ｎｚは光学異方性層の厚さ方向の屈折率を、ｄは光学異方性層の厚さ（ｎｍ）をそれぞれ表す。屈折率の測定波長は５９０ｎｍである。）〕
　前記第２光学異方性層のＲｏ（２）（５９０ｎｍ）は２０～１５０ｎｍであるのが好ましく、４０～１１０ｎｍであるのがさらに好ましい。また、前記第２光学異方性層のＲｔ（２）（５９０）は１００～３００ｎｍであるのが好ましく、１４０～２６０ｎｍであるのがさらに好ましい。 (Optical properties of cellulose ester film)
The cellulose ester film used for the second optically anisotropic layer is combined with the first optically anisotropic layer having predetermined optical characteristics to widen the viewing angle of a liquid crystal display device, particularly an IPS mode liquid crystal display device. In order to contribute to this, it is necessary to satisfy the following relational expressions (I) to (III).
Relational expression (I): nx>ny> nz
Relational formula (II): 20 nm ≦ Ro (2) (590 nm) ≦ 150 nm,
Relational expression (III): 100 nm ≦ Rt (2) (590 nm) ≦ 300 nm
[However, the refractive indexes of the first optical anisotropic layer and the second optical anisotropic layer are defined by the following nx, ny, and nz,
Ro (1) = (nx−ny) × d
Rt (1) = ((nx + ny) / 2−nz) × d,
And Ro (2) = (nx−ny) × d
Rt (2) = ((nx + ny) / 2−nz) × d
Indicated by
(Where nx is the refractive index in the width direction in the plane of the optically anisotropic layer, ny is the film forming or conveying direction in the plane of the optically anisotropic layer, and is in the direction perpendicular to nx in the plane) The refractive index, nz represents the refractive index in the thickness direction of the optically anisotropic layer, d represents the thickness (nm) of the optically anisotropic layer, and the measurement wavelength of the refractive index is 590 nm.)]
The Ro (2) (590 nm) of the second optically anisotropic layer is preferably 20 to 150 nm, and more preferably 40 to 110 nm. In addition, Rt (2) (590) of the second optically anisotropic layer is preferably 100 to 300 nm, and more preferably 140 to 260 nm.
　また、本発明では面配向度を表す第２光学異方性層のＮｚパラメータを、Ｎｚ＝Ｒｔ／Ｒｏ＋０．５と定義すると、Ｎｚは好ましくは１．５～７．０に調節する。２．０～５．５がさらに好ましくに調節する。２．５～４．５であることが特に好ましい。これらの調整は添加剤の種類、添加量及び延伸倍率により行うことができる。 In the present invention, when the Nz parameter of the second optical anisotropic layer representing the degree of plane orientation is defined as Nz = Rt / Ro + 0.5, Nz is preferably adjusted to 1.5 to 7.0. 2.0 to 5.5 is more preferably adjusted. Particularly preferred is 2.5 to 4.5. These adjustments can be made according to the type of additive, the amount added, and the draw ratio.
　本明細書において、Ｒｏ（λｎｍ）、Ｒｔ（λｎｍ）は各々、測定波長λｎｍにおける面内のリターデーション及び厚さ方向のリターデーションを表す。 In the present specification, Ro (λnm) and Rt (λnm) respectively represent in-plane retardation and retardation in the thickness direction at the measurement wavelength λnm.
　Ｒｏ（λｎｍ）はＫＯＢＲＡ－２１ＡＤＨ（王子計測機器（株）製）において波長λｎｍの光をフィルム法線方向に入射させて測定される。 Ro (λnm) is measured by making light of wavelength λnm incident in the normal direction of the film in KOBRA-21ADH (manufactured by Oji Scientific Instruments).
　Ｒｔ（λ）は前記Ｒｏ（λ）、面内の遅相軸（ＫＯＢＲＡ－２１ＡＤＨにより判断される）を傾斜軸（回転軸）としてフィルム法線方向に対して＋４０°傾斜した方向から波長λｎｍの光を入射させて測定したリターデーション値、及び面内の遅相軸を傾斜軸（回転軸）としてフィルム法線方向に対して－４０°傾斜した方向から波長λｎｍの光を入射させて測定したリターデーション値の計３つの方向で測定したリターデーション値を基にＫＯＢＲＡ　２１ＡＤＨが算出する。 Rt (λ) is the wavelength of λnm from the direction inclined by + 40 ° with respect to the normal direction of the film, with the in-plane slow axis (determined by KOBRA-21ADH) as the tilt axis (rotary axis). Retardation value measured by making light incident, and measuring by making light of wavelength λ nm incident from a direction inclined by −40 ° with respect to the normal direction of the film with the in-plane slow axis as the tilt axis (rotation axis) KOBRA 21ADH calculates based on the retardation values measured in a total of three directions.
　セルロースエステルの当該波長における平均屈折率を、アッベ屈折計と分光光源を用いて測定し、平均屈折率の測定値と膜厚を入力することで、ＫＯＢＲＡ　２１ＡＤＨにてｎｘ、ｎｙ、ｎｚを算出する。なお、本明細書において、Ｒｏ、Ｒｔについて特に波長λの記載を断らない限り、測定波長は５９０ｎｍとする。 The average refractive index of the cellulose ester at the wavelength is measured using an Abbe refractometer and a spectral light source, and nx, ny, and nz are calculated by KOBRA 21ADH by inputting the measured value of the average refractive index and the film thickness. . In the present specification, the measurement wavelength is set to 590 nm unless specifically described for Ro and Rt.
　本発明に係るセルロースエステルフィルムのフィルム面内の遅相軸角度のバラつきは、ロールフィルムの基準方向に対して－２度から＋２度の範囲にあることが好ましく、－１度から＋１度の範囲にあることがさらに好ましく、－０．５度から＋０．５度の範囲にあることが最も好ましい。ここで、基準方向とは、セルロースエステルフィルムを縦延伸する場合はロールフィルムの長手方向であり、横延伸する場合はロールフィルムの幅方向である。 The variation of the slow axis angle in the film plane of the cellulose ester film according to the present invention is preferably in the range of -2 to +2 degrees with respect to the reference direction of the roll film, and in the range of -1 to +1 degrees. Is more preferable, and most preferably in the range of −0.5 ° to + 0.5 °. Here, the reference direction is the longitudinal direction of the roll film when the cellulose ester film is longitudinally stretched, and the width direction of the roll film when laterally stretched.
　また、本発明に係るセルロースエステルフィルムは、２５℃１０％ＲＨにおけるＲｏ値と２５℃８０％ＲＨにおけるＲｏ値との差ΔＲｏ（＝Ｒｏ１０％ＲＨ－Ｒｏ８０％ＲＨ）が０～１０ｎｍであり、２５℃１０％ＲＨにおけるＲｔ値と２５℃８０％ＲＨにおけるＲｔ値との差ΔＲｔ（＝Ｒｔ（１０％ＲＨ）－Ｒｔ（８０％ＲＨ））が０～３０ｎｍであるのが、液晶表示装置の経時による色味変化を少なくする上で好ましい。 In the cellulose ester film according to the present invention, the difference ΔRo (= Ro 10% RH−Ro 80% RH) between the Ro value at 25 ° C. and 10% RH and the Ro value at 25 ° C. and 80% RH is 0 to 10 nm. The difference ΔRt (= Rt (10% RH) −Rt (80% RH)) between the Rt value at 25 ° C. and 80% RH at 0 ° C. is 0 to 30 nm. It is preferable in reducing the color change due to.
　また、本発明に係るセルロースエステルフィルムは、２５℃８０％ＲＨにおける平衡含水率が３．２％以下であるのが、液晶表示装置の経時による色味変化を少なくする上で好ましい。 In addition, the cellulose ester film according to the present invention preferably has an equilibrium water content of not more than 3.2% at 25 ° C. and 80% RH in order to reduce the color change with time of the liquid crystal display device.
　含水率の測定法は、本発明に係るセルロースエステルフィルム試料７ｍｍ×３５ｍｍを水分測定器、試料乾燥装置（ＣＡ－０３、ＶＡ－０５、共に三菱化学（株））にてカールフィッシャー法で測定する。水分量（ｇ）を試料質量（ｇ）で除して算出する。 The moisture content is measured by measuring a cellulose ester film sample 7 mm × 35 mm according to the present invention by a Karl Fischer method using a moisture measuring device and a sample drying apparatus (CA-03, VA-05, both Mitsubishi Chemical Corporation). . It is calculated by dividing the amount of water (g) by the sample mass (g).
　また、本発明に係る第２光学異方性層に用いるセルロースエステルフィルムは、６０℃、９５％ＲＨにおける透湿度が、６００ｇ／ｍ２・２４ｈｒ以上１５００ｇ／ｍ２・２４ｈｒ以下であることが、液晶表示装置の経時による色味変化を少なくする上で必要である。 In addition, the cellulose ester film used for the second optically anisotropic layer according to the present invention has a moisture permeability at 60 ° C. and 95% RH of 600 g / m 2 · 24 hr to 1500 g / m 2 · 24 hr. This is necessary to reduce the color change of the liquid crystal display device over time.
　前記セルロースエステルフィルムの膜厚が厚ければ透湿度は小さくなり、膜厚が薄ければ透湿度は大きくなる。 When the film thickness of the cellulose ester film is thick, the moisture permeability becomes small, and when the film thickness is thin, the moisture permeability becomes large.
　なお、本発明に係る透湿度については、ＪＩＳ　Ｚ　０２０８のカップ法に準じて、６０℃、９５％ＲＨ、２４時間の条件に変更して透湿度を決定した。 In addition, about the water vapor transmission rate concerning this invention, it changed into the conditions of 60 degreeC, 95% RH, and 24 hours according to the cup method of JISZ0208, and determined the water vapor transmission rate.
　また、本発明に係るセルロースエステルフィルムは、ヘイズが０．０１～２％であるのが、好ましい。ここで、ヘイズは、以下のようにして測定できる。 Further, the cellulose ester film according to the present invention preferably has a haze of 0.01 to 2%. Here, the haze can be measured as follows.
　ヘイズの測定は、本発明に係るセルロースエステルフィルム試料４０ｍｍ×８０ｍｍを、２５℃，６０％ＲＨでヘイズメーター（ＮＤＨ２０００型、日本電色工業（株）製）でＪＩＳ　Ｋ－６７１４に従って測定する。 The haze is measured by measuring a 40 mm × 80 mm cellulose ester film sample according to the present invention at 25 ° C. and 60% RH with a haze meter (NDH2000 type, manufactured by Nippon Denshoku Industries Co., Ltd.) according to JIS K-6714.
　また、本発明に係るセルロースエステルフィルムは、８０℃、９０％ＲＨの条件下に４８時間静置した場合の質量変化が、０～５％であるのが、好ましい。 The cellulose ester film according to the present invention preferably has a mass change of 0 to 5% when left for 48 hours under conditions of 80 ° C. and 90% RH.
　また、本発明に係るセルロースエステルフィルムは、６０℃、９５％ＲＨの条件下に２４時間静置した場合の寸度変化及び９０℃、５％ＲＨの条件下に２４時間静置した場合の寸度変化が、いずれも０～５％であるのが、好ましい。 In addition, the cellulose ester film according to the present invention has a dimensional change when allowed to stand for 24 hours under conditions of 60 ° C. and 95% RH, and a dimension when allowed to stand for 24 hours under conditions of 90 ° C. and 5% RH. The degree of change is preferably 0 to 5%.
　光弾性係数が、５０×１０－１３ｃｍ２／ｄｙｎｅ以下であるのが、液晶表示装置の経時による色味変化を少なくする上で好ましい。 It is preferable that the photoelastic coefficient is 50 × 10 −13 cm 2 / dyne or less in order to reduce the color change with time of the liquid crystal display device.
　具体的な測定方法としては、ＫＯＢＲＡ－３１ＰＲＷを用いて、１Ｎ～１５Ｎの範囲で１０点の応力で引っ張り、その際発現する位相差の測定を行い、各点での張力と位相差をプロットして、その傾きから算出する。 As a specific measurement method, using KOBRA-31PRW, pulling with 10 points of stress in the range of 1N to 15N, measuring the phase difference that occurs, plotting the tension and phase difference at each point And calculating from the inclination.
　（第１光学異方性層）
　本発明に係る第１光学異方性層は、負の複屈折発現性を示す樹脂で構成されたフィルムであって、面内のリターデーションＲｏ（１）が－４０～２０ｎｍの範囲内であり、かつ、厚さ方向のリターデーションＲｔ（１）が－４００～－８０ｎｍの範囲内であることを特徴とする。 (First optical anisotropic layer)
The first optically anisotropic layer according to the present invention is a film composed of a resin exhibiting negative birefringence and having an in-plane retardation Ro (1) in the range of −40 to 20 nm. The retardation Rt (1) in the thickness direction is in the range of −400 to −80 nm.
　本発明に係る第１光学異方性層のフィルム面内の遅相軸角度のバラつきは、ロールフィルムであるときに基準方向に対して－２度から＋２度の範囲にあることが好ましく、－１度から＋１度の範囲にあることがさらに好ましく、－０．５度から＋０．５度の範囲にあることが最も好ましい。ここで、基準方向とは、第１光学異方性層のロールフィルムの長手方向、又は第１光学異方性層のロールフィルムの幅方向である。 The variation of the slow axis angle in the film plane of the first optically anisotropic layer according to the present invention is preferably in the range of −2 degrees to +2 degrees with respect to the reference direction when the film is a roll film, More preferably, it is in the range of 1 degree to +1 degree, and most preferably in the range of -0.5 degree to +0.5 degree. Here, the reference direction is the longitudinal direction of the roll film of the first optical anisotropic layer or the width direction of the roll film of the first optical anisotropic layer.
　また、第１光学異方性層を構成するフィルムの６０℃、９５％ＲＨ、２４ｈｒの透湿度は、複屈折ムラ、偏光子の劣化、画像表示の劣化等の防止の観点から、２０～６００ｇ／ｍ２・２４ｈであることを特徴とする。 Further, the moisture permeability of the film constituting the first optically anisotropic layer at 60 ° C., 95% RH, and 24 hr is 20 to 600 g from the viewpoint of preventing birefringence unevenness, polarizer deterioration, image display deterioration, and the like. / M 2 · 24h.
　本発明においては、上記特徴を実現するために第１光学異方性層を下記の要件等を満たすアクリル樹脂含有フィルムを用いて構成することが好ましい。 In the present invention, in order to realize the above characteristics, it is preferable to configure the first optically anisotropic layer using an acrylic resin-containing film that satisfies the following requirements.
　〈アクリル樹脂含有フィルム〉
　本発明に係るアクリル樹脂含有フィルムは、ヘイズ値が１％未満であり、張力軟化点が１０５～１４５℃で、かつ延性破壊が起こらず、面内のリターデーションＲｏ（１）が－４０～２０ｎｍの範囲内であり、かつ、厚さ方向のリターデーションＲｔ（１）が－４００～－８０ｎｍの範囲内であることを特徴とする。 <Acrylic resin-containing film>
The acrylic resin-containing film according to the present invention has a haze value of less than 1%, a tension softening point of 105 to 145 ° C., no ductile fracture, and an in-plane retardation Ro (1) of −40 to 20 nm. The retardation Rt (1) in the thickness direction is in the range of −400 to −80 nm.
　これらのリターデーションＲｏ（１）、及びＲｔ（１）は、フィルムを製造するときに、延伸する工程で制御することが好ましい。特に本発明に係る光学異方性層は、延伸によって負の複屈折性を発現する樹脂を用いるので、延伸したフィルムを用いることがＲｏ（１）は、ゼロでない値にすることができる点で優れている。液晶セルのコントラストを改善するために、フィルムの延伸によって微調整が可能になり、Ｒｏがゼロでないことが液晶表示装置の色味を改善できることがある。これは、第２光学異方性層のＲｏ（２）がゼロでないために、本発明の構成１（図２参照）又は構成２（図３参照）に第１光学異方性層を配置するときに、Ｒｏ（１）がゼロでないことと波長分散性が異なるために、第１光学異方性層のＲｏ（１）と第２光学異方性層のＲｏ（２）を複合することで波長分散性を制御することができる点で優れている。第１光学異方性層が、支持体に対して垂直配向性の液晶を用いて常法によって配向を固定化した光学補償フィルムは、フィルムの面内リターデーションであるＲｏが設計上ゼロになる観点と、延伸することで得られる第１光学異方性層及び第２光学異方性層の面内リターデーションを複合する設計とは原理的に異なっていることは明らかである。 These retardations Ro (1) and Rt (1) are preferably controlled in a stretching process when a film is produced. In particular, since the optically anisotropic layer according to the present invention uses a resin that develops negative birefringence by stretching, it is possible to set Ro (1) to a non-zero value by using a stretched film. Are better. In order to improve the contrast of the liquid crystal cell, fine adjustment is possible by stretching the film, and if the Ro is not zero, the color of the liquid crystal display device may be improved. This is because the Ro (2) of the second optically anisotropic layer is not zero, and therefore the first optically anisotropic layer is disposed in Configuration 1 (see FIG. 2) or Configuration 2 (see FIG. 3) of the present invention. Sometimes Ro (1) is not zero and wavelength dispersibility is different, so that Ro (1) of the first optical anisotropic layer and Ro (2) of the second optical anisotropic layer are combined. It is excellent in that the wavelength dispersion can be controlled. The optical compensation film in which the first optically anisotropic layer has an alignment fixed by a normal method using a liquid crystal having a vertical alignment with respect to the support is designed to have an in-plane retardation of Ro of zero. It is obvious that the viewpoint and the design that combines the in-plane retardation of the first optical anisotropic layer and the second optical anisotropic layer obtained by stretching are different in principle.
　本発明に係るアクリル樹脂含有フィルムの面内リターデーションＲｏは、例えば２３℃、５５％ＲＨの環境下で、５９０ｎｍの光源を用いて、アッベ屈折率計－４Ｔで樹脂の平均屈折率を測定し、ＫＯＢＲＡ－２１ＡＤＨ（王子計測機器（株））の測定時に、アッベ屈折率計による平均屈折率を入力して、求めることができる。 The in-plane retardation Ro of the acrylic resin-containing film according to the present invention is obtained by, for example, measuring the average refractive index of the resin with an Abbe refractometer-4T using a light source of 590 nm in an environment of 23 ° C. and 55% RH. , KOBRA-21ADH (Oji Scientific Instruments Co., Ltd.) can be obtained by inputting the average refractive index by an Abbe refractometer.
　本発明における延性破壊とは、ある材料が有する強度よりも、大きな応力が作用することで生じるものであり、最終破断までに材料の著しい伸びや絞りを伴う破壊と定義される。その破面には、ディンプルと呼ばれる窪みが無数に形成される特徴がある。 In the present invention, the ductile fracture is caused by a stress that is greater than the strength of a certain material, and is defined as a fracture accompanied by significant elongation or squeezing of the material before the final fracture. The fracture surface is characterized by numerous indentations called dimples.
　従って「延性破壊が起こらないアクリル樹脂含有フィルム」とは、２３℃、５５％ＲＨにおいて、フィルムを２つに折り曲げるような大きな応力を作用させても破断等の破壊がみられないこと、具体的には、折り曲げてもフィルムが折れないことをいう。 Therefore, “an acrylic resin-containing film that does not cause ductile fracture” means that, at 23 ° C. and 55% RH, even when a large stress that bends the film in two is applied, no fracture or the like is observed. Means that the film does not break even when folded.
　延性破壊の起こらないアクリル樹脂含有フィルムは、用いるアクリル樹脂やセルロースエステル、その他添加剤等の材料構成を後述のように選択することにより得ることができる。 An acrylic resin-containing film in which ductile fracture does not occur can be obtained by selecting the material configuration of the acrylic resin, cellulose ester, and other additives used as described below.
　本発明に係るアクリル樹脂含有フィルムは、ヘイズを低くし、プロジェクターのような高温になる機器や、車載用表示機器のような、高温の環境下での使用を考慮すると、その張力軟化点を、１０５℃～１４５℃とすることが好ましく、１１０℃～１３０℃に制御することがより好ましい。 The acrylic resin-containing film according to the present invention has a low haze, a high temperature device such as a projector, and a use in a high temperature environment such as an in-vehicle display device. The temperature is preferably 105 ° C to 145 ° C, and more preferably controlled to 110 ° C to 130 ° C.
　アクリル樹脂含有フィルムの張力軟化点温度の具体的な測定方法としては、テンシロン試験機（ＯＲＩＥＮＴＥＣ（株）製、ＲＴＣ－１２２５Ａ）を用いて、アクリル樹脂含有フィルムを１２０ｍｍ（縦）×１０ｍｍ（幅）で切り出し、１０Ｎの張力で引っ張りながら３０℃／ｍｉｎの昇温速度で昇温を続け、９Ｎになった時点での温度を３回測定し、その平均値により求めることができる。 As a specific method for measuring the tension softening point temperature of the acrylic resin-containing film, a tensilon tester (ORIENTEC Co., Ltd., RTC-1225A) was used, and the acrylic resin-containing film was 120 mm (length) × 10 mm (width). The temperature is increased at a rate of temperature increase of 30 ° C./min while pulling at a tension of 10 N, and the temperature at the time of 9 N is measured three times, and the average value can be obtained.
　本発明に係るアクリル樹脂含有フィルムは、ガラス転移温度（Ｔｇ）が１１０℃以上であることが好ましい。より好ましくは１２０℃以上である。特に好ましくは１５０℃以上である。 The acrylic resin-containing film according to the present invention preferably has a glass transition temperature (Tg) of 110 ° C. or higher. More preferably, it is 120 ° C. or higher. Especially preferably, it is 150 degreeC or more.
　尚、ここでいうガラス転移温度とは、示差走査熱量測定器（Ｐｅｒｋｉｎ　Ｅｌｍｅｒ（株）製ＤＳＣ－７型）を用いて、昇温速度２０℃／分で測定し、ＪＩＳ　Ｋ７１２１（１９８７）に従い求めた中間点ガラス転移温度（Ｔｍｇ）である。 The glass transition temperature here is measured at a heating rate of 20 ° C./min using a differential scanning calorimeter (DSC-7, manufactured by Perkin Elmer Co., Ltd.), and determined according to JIS K7121 (1987). The intermediate glass transition temperature (Tmg).
　本発明に係るアクリル樹脂含有フィルムは、フィルム面内の直径５μｍ以上の欠点が１個／１０ｃｍ四方以下である。更に好ましくは０．５個／１０ｃｍ四方以下、一層好ましくは０．１個／１０ｃｍ四方以下である。 The acrylic resin-containing film according to the present invention has a defect of 5 μm or more in diameter in the film plane of 1 piece / 10 cm square or less. More preferably, it is 0.5 piece / 10 cm square or less, more preferably 0.1 piece / 10 cm square or less.
　ここで欠点の直径とは、欠点が円形の場合はその直径を示し、円形でない場合は欠点の範囲を下記方法により顕微鏡で観察して決定し、その最大径（外接円の直径）とする。 Here, the diameter of the defect indicates the diameter when the defect is circular, and when it is not circular, the range of the defect is determined by observing with a microscope according to the following method, and the maximum diameter (diameter of circumscribed circle) is determined.
　欠点の範囲は、欠点が気泡や異物の場合は、欠点を微分干渉顕微鏡の透過光で観察したときの影の大きさである。欠点が、ロール傷の転写や擦り傷など、表面形状の変化の場合は、欠点を微分干渉顕微鏡の反射光で観察して大きさを確認する。 The range of the defect is the size of the shadow when the defect is observed with the transmitted light of the differential interference microscope when the defect is a bubble or a foreign object. When the defect is a change in the surface shape, such as transfer of a roll flaw or an abrasion, the size is confirmed by observing the defect with the reflected light of a differential interference microscope.
　なお、反射光で観察する場合に、欠点の大きさが不明瞭であれば、表面にアルミや白金を蒸着して観察する。 In addition, when observing with reflected light, if the size of the defect is not clear, aluminum or platinum is vapor-deposited on the surface for observation.
　かかる欠点頻度にて表される品位に優れたフィルムを生産性よく得るには、ポリマー溶液を流延直前に高精度濾過することや、流延機周辺のクリーン度を高くすること、また、流延後の乾燥条件を段階的に設定し、効率よくかつ発泡を抑えて乾燥させることが有効である。 In order to obtain a film having excellent quality expressed by such a defect frequency with high productivity, it is necessary to filter the polymer solution with high precision immediately before casting, to increase the cleanliness around the casting machine, It is effective to set drying conditions after rolling stepwise and to dry efficiently while suppressing foaming.
　欠点の個数が１個／１０ｃｍ四方より多いと、例えば後工程での加工時などでフィルムに張力がかかると、欠点を基点としてフィルムが破断して生産性が著しく低下する場合がある。また、欠点の直径が５μｍ以上になると、偏光板観察などにより目視で確認でき、光学部材として用いたとき輝点が生じる場合がある。 When the number of defects is more than 1/10 cm square, for example, when a tension is applied to the film during processing in a later process, the film breaks with the defect as a starting point, and the productivity may be significantly reduced. Moreover, when the diameter of a defect becomes 5 micrometers or more, it can confirm visually by polarizing plate observation etc., and when used as an optical member, a bright spot may arise.
　また、目視で確認できない場合でも、該フィルム上にハードコート層などを形成したときに、塗剤が均一に形成できず欠点（塗布抜け）となる場合がある。ここで、欠点とは、溶液製膜の乾燥工程において溶媒の急激な蒸発に起因して発生するフィルム中の空洞（発泡欠点）や、製膜原液中の異物や製膜中に混入する異物に起因するフィルム中の異物（異物欠点）を言う。 Also, even when visual confirmation is not possible, when a hard coat layer or the like is formed on the film, the coating agent may not be formed uniformly, resulting in defects (coating defects). Here, the defect is a void in the film (foaming defect) generated due to the rapid evaporation of the solvent in the drying process of the solution casting, a foreign matter in the film forming stock solution, or a foreign matter mixed in the film forming. This refers to the foreign matter (foreign matter defect) in the film.
　本発明に係るアクリル樹脂含有フィルムは、溶液流延製膜法又は溶融押出製膜法によりフィルムの原反を製造して、乾燥したフィルムを加熱により軟化させて延伸操作を行うか、あるいは溶液流延製膜法で溶媒が残存している状態で延伸操作を行いその後乾燥を行いフィルムを得ることで、延伸に対して光学的に負のリターデーションを発現させることができる。 The acrylic resin-containing film according to the present invention is produced by producing a raw film of a film by a solution casting film forming method or a melt extrusion film forming method, and performing a stretching operation by softening the dried film by heating. By carrying out a stretching operation in a state in which the solvent remains by the film-forming method and then drying to obtain a film, an optically negative retardation can be expressed with respect to stretching.
　このために延伸前のフィルムに欠点が存在すると、リターデーションを発現させるための延伸操作により、欠点の直径が拡大することがある。 For this reason, if there is a defect in the film before stretching, the diameter of the defect may be increased by a stretching operation for developing retardation.
　従って上記のフィルム中の欠点は、リターデーションを発現させるための延伸操作後の直径及び個数として、フィルム面内の直径５μｍ以上の欠点が１個／１０ｃｍ四方以下である。更に好ましくは０．５個／１０ｃｍ四方以下、一層好ましくは０．１個／１０ｃｍ四方以下である。 Therefore, the defects in the above-mentioned film are 1/10 cm square or less of defects having a diameter of 5 μm or more in the film plane as the diameter and number after the stretching operation for developing retardation. More preferably, it is 0.5 piece / 10 cm square or less, more preferably 0.1 piece / 10 cm square or less.
　また、本発明に係るアクリル樹脂含有フィルムは、ＪＩＳ－Ｋ７１２７－１９９９に準拠した測定において、少なくとも一方向の破断伸度が、１０％以上であることが好ましく、より好ましくは２０％以上である。 The acrylic resin-containing film according to the present invention preferably has a breaking elongation in at least one direction of 10% or more, more preferably 20% or more, as measured in accordance with JIS-K7127-1999.
　破断伸度の上限は特に限定されるものではないが、現実的には２５０％程度である。破断伸度を大きくするには異物や発泡に起因するフィルム中の欠点を抑制することが有効である。 The upper limit of the elongation at break is not particularly limited, but is practically about 250%. In order to increase the elongation at break, it is effective to suppress defects in the film caused by foreign matter and foaming.
　本発明に係るアクリル樹脂含有フィルムの膜厚に特に制限はないが、後述する偏光板保護フィルムに使用する場合は２０～２００μｍであることが好ましく、溶液製膜法でフィルム化する場合は、塗布性、発泡、溶媒乾燥などの観点から、２５～１００μｍであることがより好ましく、３０～８０μｍであることが特に好ましい。 The film thickness of the acrylic resin-containing film according to the present invention is not particularly limited, but is preferably 20 to 200 μm when used for a polarizing plate protective film described later. From the viewpoints of properties, foaming, solvent drying, etc., it is more preferably 25 to 100 μm, particularly preferably 30 to 80 μm.
　本発明に係るアクリル樹脂含有フィルムは、その全光線透過率が９０％以上であることが好ましく、より好ましくは９３％以上である。また、現実的な上限としては、９９％程度である。かかる全光線透過率にて表される優れた透明性を達成するには、可視光を吸収する添加剤や共重合成分を導入しないようにすることや、ポリマー中の異物を高精度濾過により除去し、フィルム内部の光の拡散や吸収を低減させることが有効である。 The acrylic resin-containing film according to the present invention preferably has a total light transmittance of 90% or more, more preferably 93% or more. Moreover, as a realistic upper limit, it is about 99%. In order to achieve excellent transparency expressed by such total light transmittance, it is necessary not to introduce additives and copolymerization components that absorb visible light, or to remove foreign substances in the polymer by high-precision filtration. It is effective to reduce the diffusion and absorption of light inside the film.
　また、製膜時のフィルム接触部（冷却ロール、カレンダーロール、ドラム、ベルト、溶液製膜における塗布基材、搬送ロールなど）の表面粗さを小さくしてフィルム表面の表面粗さを小さくすることや、アクリル樹脂の屈折率を小さくすることによりフィルム表面の光の拡散や反射を低減させることが有効である。 Also, reduce the surface roughness of the film surface by reducing the surface roughness of the film contact part (cooling roll, calender roll, drum, belt, coating substrate in solution casting, transport roll, etc.) during film formation. It is also effective to reduce the diffusion and reflection of light on the film surface by reducing the refractive index of the acrylic resin.
　本発明に係るアクリル樹脂含有フィルムは、透明性を表す指標の１つであるヘイズ値（濁度）が１．０％以下であることが特徴であるが、液晶表示装置に組み込んだ際の輝度、コントラストの点から好ましくは０．５％以下である。 The acrylic resin-containing film according to the present invention is characterized in that the haze value (turbidity), which is one of the indices indicating transparency, is 1.0% or less, but the luminance when incorporated in a liquid crystal display device From the viewpoint of contrast, it is preferably 0.5% or less.
　かかるヘイズ値を達成するには、ポリマー中の異物を高精度濾過により除去し、フィルム内部の光の拡散を低減させることが有効である。 In order to achieve such a haze value, it is effective to remove foreign substances in the polymer by high-precision filtration and reduce the diffusion of light inside the film.
　アクリル粒子を使用する場合は、アクリル系樹脂とアクリル粒子との屈折率差を小さくすることも有効である。 When using acrylic particles, it is also effective to reduce the difference in refractive index between the acrylic resin and the acrylic particles.
　また、表面の粗さも表面ヘイズとしてヘイズ値に影響するため、アクリル粒子の粒子径や添加量を前記範囲内に抑えたり、製膜時のフィルム接触部の表面粗さを小さくすることも、有効である。 In addition, since the surface roughness also affects the haze value as surface haze, it is also effective to suppress the particle diameter and addition amount of acrylic particles within the above range, or to reduce the surface roughness of the film contact portion during film formation It is.
　尚、上記アクリル樹脂含有フィルムの全光線透過率及びヘイズ値は、ＪＩＳ－Ｋ７３６１－１－１９９７及びＪＩＳ－Ｋ７１３６－２０００に従い、測定した値である。 The total light transmittance and haze value of the acrylic resin-containing film are values measured according to JIS-K7361-1-1997 and JIS-K7136-2000.
　本発明に係るアクリル樹脂含有フィルムは、上記のような物性を満たしていれば、光学用のアクリル樹脂含有フィルムとして好ましく用いることができるが、以下の組成とすることにより、加工性、耐熱性に優れたフィルムを得ることができる。 The acrylic resin-containing film according to the present invention can be preferably used as an acrylic resin-containing film for optical use as long as it satisfies the physical properties as described above. An excellent film can be obtained.
　すなわち、加工性及び耐熱性を両立させる観点から、前記アクリル樹脂含有フィルムが、アクリル樹脂とセルロースエステル樹脂を９５：５～３０：７０の質量比で含有し、該セルロースエステル樹脂のアシル基の総置換度（Ｔ）が２．００～３．００、アセチル基置換度（ａｃ）が０～１．８９、アセチル基以外のアシル基の炭素数が３～７であり、重量平均分子量（Ｍｗ）が７５０００～２８００００であることを特徴とするアクリル樹脂含有フィルムにより、本発明の優れた効果が得られる。 That is, from the viewpoint of achieving both workability and heat resistance, the acrylic resin-containing film contains an acrylic resin and a cellulose ester resin in a mass ratio of 95: 5 to 30:70, and the total acyl groups of the cellulose ester resin. The degree of substitution (T) is 2.00 to 3.00, the degree of substitution of acetyl group (ac) is 0 to 1.89, the number of carbons of acyl groups other than acetyl groups is 3 to 7, and the weight average molecular weight (Mw) The excellent effect of the present invention can be obtained by an acrylic resin-containing film characterized by having an A of 75,000 to 280000.
　本発明に係るアクリル樹脂含有フィルムにおいて、アクリル樹脂とセルロースエステル樹脂は、９５：５～３０：７０の質量比で含有されるが、好ましくはアクリル樹脂が５０質量％以上である。 In the acrylic resin-containing film according to the present invention, the acrylic resin and the cellulose ester resin are contained in a mass ratio of 95: 5 to 30:70, but the acrylic resin is preferably 50% by mass or more.
　アクリル樹脂成分が多くなると、例えば高温・高湿下での寸法変化が抑制され、偏光板として用いた時の偏光板のカールやパネルの反りを著しく低減することができる。 When the acrylic resin component is increased, for example, the dimensional change under high temperature and high humidity is suppressed, and curling of the polarizing plate and warping of the panel when used as a polarizing plate can be remarkably reduced.
　さらに、アクリル樹脂成分が半分以上の組成においては、上記物性をより長時間維持することが可能となる。 Furthermore, in a composition having more than half of the acrylic resin component, the above physical properties can be maintained for a longer time.
　アクリル樹脂とセルロースエステル樹脂の総質量は、アクリル樹脂含有フィルムの５５～１００質量％であり、好ましくは６０～９９質量％である。 The total mass of the acrylic resin and the cellulose ester resin is 55 to 100% by mass, preferably 60 to 99% by mass of the acrylic resin-containing film.
　〈アクリル樹脂〉
　本発明に用いられるアクリル樹脂には、メタクリル樹脂も含まれる。アクリル樹脂は、固有複屈折が－０．００５以下であることを特徴とする。 <acrylic resin>
The acrylic resin used in the present invention includes a methacrylic resin. The acrylic resin is characterized by having an intrinsic birefringence of −0.005 or less.
　ここで、アクリル樹脂の固有複屈折が－０．００５以下であるとは、アクリル樹脂が一種又は複数のアクリル樹脂からなる場合に、アクリル樹脂全体として固有複屈折が－０．００５以下であることをいう。好ましくは－０．０１以下である。 Here, the intrinsic birefringence of the acrylic resin being −0.005 or less means that the intrinsic birefringence of the entire acrylic resin is −0.005 or less when the acrylic resin is made of one or more acrylic resins. Say. Preferably it is -0.01 or less.
　フィルムの厚さ変動や製膜時の機械変動が要因となって、リターデーションのムラが発生しやすくなることから、アクリルフィルムが良好な位相差フィルムとして機能するためには、負の固有複屈折が好ましい。 Because retardation variations are likely to occur due to film thickness variations and mechanical variations during film formation, negative intrinsic birefringence is necessary for acrylic films to function as good retardation films. Is preferred.
　本発明に係るアクリルフィルムは、偏光板保護フィルムと位相差フィルムの機能を兼ねた性能をもつことに特徴がある。 The acrylic film according to the present invention is characterized in that it has the functions of a polarizing plate protective film and a retardation film.
　アクリル樹脂の固有複屈折を－０．００５以下とするためには、例えば、アクリル系モノマーに、スチレン系モノマー、マレイミド系モノマー等の誘導体の中で、ホモポリマーでは負の固有複屈折を有する樹脂モノマーを共重合させたり、負の固有複屈折の大きい樹脂を混合することがあげられ、ホモポリマーでは負の固有複屈折を有する樹脂モノマー共重合させた樹脂であることが好ましい。 In order to set the intrinsic birefringence of the acrylic resin to -0.005 or less, for example, among acrylic monomers, styrene monomers, maleimide monomers and other derivatives, homopolymers have negative intrinsic birefringence. Monomers are copolymerized or a resin having a large negative intrinsic birefringence is mixed. A homopolymer is preferably a resin obtained by copolymerizing a resin monomer having a negative intrinsic birefringence.
　また、正の固有複屈折を発現させるホモポリマーを、共重合のモノマーとして用いたりブレンドしたりして、複屈折の波長分散性を制御してもよい。 Also, a homopolymer that exhibits positive intrinsic birefringence may be used as a monomer for copolymerization or blended to control the wavelength dispersion of birefringence.
　本発明に係るアクリル樹脂は、アクリル系モノマー５０～９９質量％、及びこれと共重合可能な他のモノマー１～５０質量％からなるものが好ましい。 The acrylic resin according to the present invention is preferably composed of 50 to 99% by mass of an acrylic monomer and 1 to 50% by mass of another monomer copolymerizable therewith.
　本発明に係るアクリル樹脂を形成するアクリル系モノマーとしては、アルキル数の炭素数が１～１８のアルキルメタクリレート、アルキル数の炭素数が１～１８のアルキルアクリレートが挙げられる。 Examples of the acrylic monomer that forms the acrylic resin according to the present invention include alkyl methacrylates having 1 to 18 carbon atoms in the alkyl number and alkyl acrylates having 1 to 18 carbon atoms in the alkyl number.
　本発明に係るアクリル樹脂の共重合モノマーとして好ましいスチレン系モノマーとしては、例えば、スチレン、α－メチルスチレン、ｏ－メチルスチレン、ｐ－メチルスチレン、ｐ－クロロスチレン、ｐ－ニトロスチレン、ｐ－アミノスチレン、ｐ－カルボキシルスチレン、ｐ－フェニルスチレン、２，５－ジクロロスチレン、ｐ－ｔ－ブチルスチレン等が挙げられる。 Styrene monomers preferable as the copolymerization monomer for the acrylic resin according to the present invention include, for example, styrene, α-methylstyrene, o-methylstyrene, p-methylstyrene, p-chlorostyrene, p-nitrostyrene, and p-amino. Examples thereof include styrene, p-carboxyl styrene, p-phenyl styrene, 2,5-dichlorostyrene, pt-butyl styrene and the like.
　本発明に係るアクリル樹脂の共重合モノマーとして、好ましいマレイミド系モノマーとしては、例えば、Ｎ－メチルマレイミド、Ｎ－エチルマレイミド、Ｎ－シクロヘキシルマレイミド、Ｎ－ベンジルマレイミド、Ｎ－フェニルマレイミド、Ｎ－（２－メチルフェニル）マレイミド、Ｎ－（２－エチルフェニル）マレイミド、Ｎ－（２－ｎ－プロピルフェニル）マレイミド、Ｎ－（２－イソプロピルフェニル）マレイミド、Ｎ－（２，６－ジメチルフェニル）マレイミド、Ｎ－（２，６－ジエチルフェニル）マレイミド、Ｎ－（２，６－ジ－イソプロピルフェニル）マレイミド、Ｎ－（２－メチル－６－エチルフェニル）マレイミド、Ｎ－（２－クロロフェニル）マレイミド、Ｎ－（２，６－ジブロモフェニル）マレイミド、Ｎ－（２－ビフェニル）マレイミド、Ｎ－（２－シアノフェニル）マレイミド等が挙げられる。 As a copolymerizable monomer of the acrylic resin according to the present invention, preferable maleimide monomers include, for example, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, N-benzylmaleimide, N-phenylmaleimide, N- (2 -Methylphenyl) maleimide, N- (2-ethylphenyl) maleimide, N- (2-n-propylphenyl) maleimide, N- (2-isopropylphenyl) maleimide, N- (2,6-dimethylphenyl) maleimide, N- (2,6-diethylphenyl) maleimide, N- (2,6-di-isopropylphenyl) maleimide, N- (2-methyl-6-ethylphenyl) maleimide, N- (2-chlorophenyl) maleimide, N -(2,6-dibromophenyl) maleimide, N- (2-bi Eniru) maleimide, N-(2-cyanophenyl) maleimide, and the like.
　上記のマレイミド系モノマーは、例えば、東京化成工業（株）から入手することができる。 The maleimide monomer can be obtained from, for example, Tokyo Chemical Industry Co., Ltd.
　アクリル樹脂は、他のモノマーを共重合させることができる。他のモノマーとしては、例えば、エチレン、プロピレン、１－ブテン、イソブテン、１，３－ブタジエン、２－メチル－１－ブテン、２－メチル－１－ペンテン、２－メチル－２－ペンテン、１－ヘキセン、アクリロニトリル、メタクリロニトリル、アクリル酸、メタクリル酸、無水マレイン酸、酢酸ビニル等が挙げられる。 The acrylic resin can be copolymerized with other monomers. Examples of other monomers include ethylene, propylene, 1-butene, isobutene, 1,3-butadiene, 2-methyl-1-butene, 2-methyl-1-pentene, 2-methyl-2-pentene, 1- Examples include hexene, acrylonitrile, methacrylonitrile, acrylic acid, methacrylic acid, maleic anhydride, and vinyl acetate.
　本発明に係るアクリル樹脂が、スチレン系モノマー、マレイミド系モノマー以外の他のモノマーを含む場合、他のモノマーの含有率は、アクリル系モノマー以外の成分の内の、１質量％以上９０質量％以下であり、好ましくは５～４０質量％であり、特に好ましくは１０～３０質量％である。 When the acrylic resin according to the present invention contains a monomer other than the styrene monomer and the maleimide monomer, the content of the other monomer is 1% by mass or more and 90% by mass or less of the components other than the acrylic monomer. It is preferably 5 to 40% by mass, particularly preferably 10 to 30% by mass.
　本発明に係るアクリル樹脂として最も好ましくは、メチルメタクリレート・スチレン共重合体、メチルメタクリレート・スチレン・無水マレイン酸共重合体、メチルメタクリレート・スチレン・（メタ）アクリロニトリル共重合体、スチレン・メチルアクリレート共重合体、メチルアクリレート・スチレン・マレイミド共重合体、メチルメタクリレート・ビニルエステル・マレイミド共重合体、又はアクリル・オレフィン・マレイミド共重合体である。 Most preferably, the acrylic resin according to the present invention is methyl methacrylate / styrene copolymer, methyl methacrylate / styrene / maleic anhydride copolymer, methyl methacrylate / styrene / (meth) acrylonitrile copolymer, styrene / methyl acrylate copolymer. A polymer, a methyl acrylate / styrene / maleimide copolymer, a methyl methacrylate / vinyl ester / maleimide copolymer, or an acrylic / olefin / maleimide copolymer.
　アクリル樹脂として構成する樹脂を二種以上ブレンドして用いる場合は、相溶化のために、極性基を導入した樹脂を選択すること、又は相溶化剤を用いることが好ましい。この場合、光学フィルムとしての耐熱性や機械物性を著しく乱さない範囲で用いることが求められる。 When blending two or more resins constituting an acrylic resin, it is preferable to select a resin into which a polar group has been introduced or to use a compatibilizing agent for compatibilization. In this case, it is required to be used within a range that does not significantly disturb the heat resistance and mechanical properties of the optical film.
　本発明に係るアクリル樹脂の固有複屈折は、日本化学会編：「透明ポリマーの屈折率制御（季刊化学総説Ｎｏ３９）」，（１９８８）学会出版センター，ｐ．１０７．や「フィルム製膜・延伸の最適化とトラブル対策」（技術情報協会　２００７．１１．３０　第一版）を参考にして、求めることができる。 The intrinsic birefringence of the acrylic resin according to the present invention is described in the Chemical Society of Japan: “Refractive Index Control of Transparent Polymers (Quarterly Chemical Review No. 39)”, (1988) Academic Publishing Center, p. 107. Or “Optimization of film formation / stretching and troubleshooting” (Technical Information Association, 2007.11.30, 1st edition).
　一般にポリマーの配向複屈折と固有複屈折とは次の関係式によって表される。 Generally, the orientation birefringence and intrinsic birefringence of a polymer are expressed by the following relational expression.
　Δｎ＝ｆΔｎ０
　ここでΔｎは配向複屈折、ｆは配向関数、Δｎ０はポリマーの固有複屈折をそれぞれ表す。 Δn = fΔn0
Here, Δn represents orientation birefringence, f represents an orientation function, and Δn0 represents intrinsic birefringence of the polymer.
　固有複屈折の測定は、この配向複屈折と配向関数を測定することにより実験的に求められ、本発明に係るアクリル樹脂含有フィルム材料の固有複屈折は、この関係式を用いて求められる。 The measurement of intrinsic birefringence is obtained experimentally by measuring the orientation birefringence and the orientation function, and the intrinsic birefringence of the acrylic resin-containing film material according to the present invention is obtained using this relational expression.
　延伸方向に対して屈折率が低下する材料は、負の複屈折性をもつ材料と定義され、固有複屈折の符号は負となる。本発明に係るアクリル樹脂含有フィルムの固有複屈折は負であることが特徴である。 The material whose refractive index decreases with respect to the stretching direction is defined as a material having negative birefringence, and the sign of intrinsic birefringence is negative. The acrylic resin-containing film according to the present invention is characterized in that the intrinsic birefringence is negative.
　長尺のフィルムを製造するときに、幅方向の延伸と製膜方向の延伸を同時に、又は逐次に延伸工程を組み合わせてフィルムの面を平滑にすることと同時に、フィルムのリターデーションを目的の範囲に制御することができる。 When manufacturing a long film, stretching in the width direction and stretching in the film forming direction are performed simultaneously, or by combining the stretching steps sequentially to smooth the surface of the film, and at the same time, the retardation of the film is the target range. Can be controlled.
　本発明に係るアクリル樹脂含有フィルムに用いられるアクリル樹脂は、重量平均分子量（Ｍｗ）が８００００～１００００００であることが好ましい。 The acrylic resin used in the acrylic resin-containing film according to the present invention preferably has a weight average molecular weight (Mw) of 80000 to 1000000.
　本発明に係るアクリル樹脂の重量平均分子量は、ゲルパーミエーションクロマトグラフィー（ＧＰＣ法）により測定することができる。測定条件は以下の通りである。 The weight average molecular weight of the acrylic resin according to the present invention can be measured by gel permeation chromatography (GPC method). The measurement conditions are as follows.
　溶媒：　　　メチレンクロライド
　カラム：　　Ｓｈｏｄｅｘ　Ｋ８０６、Ｋ８０５、Ｋ８０３Ｇ（昭和電工（株）製を３本接続して使用した）
　カラム温度：２５℃
　試料濃度：　０．１質量％
　検出器：　　ＲＩ　Ｍｏｄｅｌ　５０４（ＧＬサイエンス（株）製）
　ポンプ：　　Ｌ６０００（日立製作所（株）製）
　流量：　　　１．０ｍｌ／ｍｉｎ
　校正曲線：　標準ポリスチレンＳＴＫ　ｓｔａｎｄａｒｄ　ポリスチレン（東ソー（株）製）Ｍｗ＝２，８００，０００～５００迄の１３サンプルによる校正曲線を使用した。１３サンプルは、ほぼ等間隔に用いることが好ましい。 Solvent: Methylene chloride Column: Shodex K806, K805, K803G (Used by connecting three Showa Denko Co., Ltd.)
Column temperature: 25 ° C
Sample concentration: 0.1% by mass
Detector: RI Model 504 (GL Science Co., Ltd.)
Pump: L6000 (manufactured by Hitachi, Ltd.)
Flow rate: 1.0ml / min
Calibration curve: Standard polystyrene STK standard polystyrene (manufactured by Tosoh Corp.) Mw = 2,800,000-500 calibration curves with 13 samples were used. The 13 samples are preferably used at approximately equal intervals.
　本発明におけるアクリル樹脂の製造方法としては、特に制限は無く、懸濁重合、乳化重合、塊状重合、あるいは溶液重合等の公知の方法のいずれを用いても良い。 The production method of the acrylic resin in the present invention is not particularly limited, and any known method such as suspension polymerization, emulsion polymerization, bulk polymerization, or solution polymerization may be used.
　ここで、重合開始剤としては、通常のパーオキサイド系及びアゾ系のものを用いることができ、また、レドックス系とすることもできる。重合温度については、懸濁又は乳化重合では３０～１００℃、塊状又は溶液重合では８０～１６０℃で実施しうる。 Here, as the polymerization initiator, a normal peroxide type or azo type can be used, and a redox type can also be used. The polymerization temperature may be 30 to 100 ° C. for suspension or emulsion polymerization, and 80 to 160 ° C. for bulk or solution polymerization.
　さらに、生成共重合体の還元粘度を制御するために、アルキルメルカプタン等を連鎖移動剤として用いて重合を実施することもできる。 Furthermore, in order to control the reduced viscosity of the produced copolymer, polymerization can be carried out using alkyl mercaptan or the like as a chain transfer agent.
　アクリル樹脂を上記分子量とすることで、耐熱性と脆性の両立を図ることができる。 By making the acrylic resin have the above molecular weight, both heat resistance and brittleness can be achieved.
　〈第１光学異方性層に用いるセルロースエステル樹脂〉
　本発明に係るアクリル樹脂含有フィルムを構成する材料において、セルロースエステル樹脂をアクリル樹脂にブレンドする場合は、アクリル樹脂から見て耐熱性を向上させることと脆性を改良する目的で用いることができる。セルロース樹脂は脂肪族のアシル基、芳香族のアシル基のいずれで置換されていても良いが、少なくともアセチル基で置換されていることが耐熱性を高くする観点で好ましい。光学フィルムへの適用の観点では、単なるブレンド以上にアクリル樹脂とセルロースエステル樹脂の両者が相溶することで画像表示装置に適した透明性をもつことができる。また、アクリル樹脂から見て、セルロースエステル樹脂を相溶させることで、フィルムに適度な透湿度を付与することができ、セルロースエステル樹脂は透湿度向上剤として機能して、本発明の偏光板に用いる第１光学異方性層としてのフィルムを得ることができる。 <Cellulose ester resin used for the first optically anisotropic layer>
In the material which comprises the acrylic resin containing film which concerns on this invention, when blending cellulose ester resin with an acrylic resin, it can use for the purpose of improving heat resistance seeing from an acrylic resin, and improving brittleness. The cellulose resin may be substituted with either an aliphatic acyl group or an aromatic acyl group, but is preferably substituted with at least an acetyl group from the viewpoint of increasing heat resistance. From the viewpoint of application to an optical film, transparency suitable for an image display device can be obtained by compatibility of both an acrylic resin and a cellulose ester resin more than a simple blend. In addition, as seen from the acrylic resin, the cellulose ester resin can be dissolved to give an appropriate moisture permeability to the film. The cellulose ester resin functions as a moisture permeability improver and is used in the polarizing plate of the present invention. A film as the first optically anisotropic layer to be used can be obtained.
　本発明に係るセルロースエステル樹脂が、脂肪族アシル基とのエステルであるとき、脂肪族アシル基は炭素原子数が２～２０で具体的にはアセチル、プロピオニル、ブチリル、イソブチリル、バレリル、ピバロイル、ヘキサノイル、オクタノイル、ラウロイル、ステアロイル等が挙げられる。アセチル基と他の脂肪族アシル基をもつ混合エステルを用いることは、アクリル樹脂の改質のために相溶させる観点で好ましく、セルロースアセテートプロピオネートやセルロースアセテートブチレートを用いることが特に好ましい。 When the cellulose ester resin according to the present invention is an ester with an aliphatic acyl group, the aliphatic acyl group has 2 to 20 carbon atoms, specifically acetyl, propionyl, butyryl, isobutyryl, valeryl, pivaloyl, hexanoyl , Octanoyl, lauroyl, stearoyl and the like. The use of a mixed ester having an acetyl group and another aliphatic acyl group is preferable from the viewpoint of compatibility for modification of the acrylic resin, and it is particularly preferable to use cellulose acetate propionate or cellulose acetate butyrate.
　本発明において前記脂肪族アシル基とはさらに置換基を有するものも包含する意味であり、置換基としては上述の芳香族アシル基において、芳香族環がベンゼン環であるとき、ベンゼン環の置換基として例示したものが挙げられる。 In the present invention, the aliphatic acyl group is meant to include those further having a substituent. When the aromatic ring is a benzene ring in the above-described aromatic acyl group, the substituent of the benzene ring Are exemplified.
　上記セルロースエステル樹脂が、芳香族アシル基とのエステルであるとき、芳香族環に置換する置換基の数は０又は１～５個であり、好ましくは１～３個で、特に好ましいのは１又は２個である。本願において、セルロースエステル樹脂に芳香族環を導入することは、負の複屈折を発現させる観点で好ましく選択できる。 When the cellulose ester resin is an ester with an aromatic acyl group, the number of substituents substituted on the aromatic ring is 0 or 1 to 5, preferably 1 to 3, particularly preferably 1 Or two. In the present application, introduction of an aromatic ring into the cellulose ester resin can be preferably selected from the viewpoint of developing negative birefringence.
　更に、芳香族環に置換する置換基の数が２個以上の時、互いに同じでも異なっていてもよいが、また、互いに連結して縮合多環化合物（例えばナフタレン、インデン、インダン、フェナントレン、キノリン、イソキノリン、クロメン、クロマン、フタラジン、アクリジン、インドール、インドリンなど）を形成してもよい。 Further, when the number of substituents substituted on the aromatic ring is 2 or more, they may be the same or different from each other, but they may be linked together to form a condensed polycyclic compound (for example, naphthalene, indene, indane, phenanthrene, quinoline). , Isoquinoline, chromene, chroman, phthalazine, acridine, indole, indoline, etc.).
　上記セルロースエステル樹脂において置換もしくは無置換の脂肪族アシル基、置換もしくは無置換の芳香族アシル基の少なくともいずれか１種選択された構造を有することが本発明に係るセルロース樹脂に用いる構造として用いられ、これらは、セルロースの単独又は混合酸エステルでもよい。 The cellulose ester resin has a structure selected from at least one of a substituted or unsubstituted aliphatic acyl group and a substituted or unsubstituted aromatic acyl group, and is used as a structure used in the cellulose resin according to the present invention. These may be cellulose alone or mixed acid esters.
　本発明に係るセルロースエステル樹脂の置換度は、アシル基の総置換度（Ｔ）が２．００～３．００であり、アセチル基は必ずしも必要ではなく、アセチル基置換度（ａｃ）が０～１．８９である。より好ましくはアセチル基以外のアシル基置換度（ｒ）が２．００～２．８９である。 The substitution degree of the cellulose ester resin according to the present invention is such that the total substitution degree (T) of the acyl group is 2.00 to 3.00, the acetyl group is not necessarily required, and the substitution degree of acetyl group (ac) is 0 to 1.89. More preferably, the acyl group substitution degree (r) other than the acetyl group is 2.00 to 2.89.
　アセチル基以外のアシル基は炭素数が３～７であることが好ましい。 The acyl group other than the acetyl group preferably has 3 to 7 carbon atoms.
　本発明に係るセルロースエステル樹脂において、炭素原子数２～７のアシル基を置換基として有するもの、即ちセルロースアセテート、セルロースプロピオネート、セルロースブチレート、セルロースアセテートプロピオネート、セルロースアセテートブチレート、セルロースアセテートベンゾエート、及びセルロースベンゾエートから選ばれる少なくとも一種であることが好ましい。 In the cellulose ester resin according to the present invention, those having an acyl group having 2 to 7 carbon atoms as a substituent, that is, cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, cellulose It is preferably at least one selected from acetate benzoate and cellulose benzoate.
　これらの中で、特に好ましいセルロースエステル樹脂は、セルロースアセテート、セルロースプロピオネート、セルロースブチレート、セルロースアセテートプロピオネートやセルロースアセテートブチレートが挙げられる。 Among these, particularly preferable cellulose ester resins include cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.
　混合脂肪酸として、さらに好ましくは、セルロースアセテートプロピオネートやセルロースアセテートブチレートの低級脂肪酸エステルであり、炭素原子数２～４のアシル基を置換基として有するものが好ましい。 More preferably, the mixed fatty acid is a lower fatty acid ester of cellulose acetate propionate or cellulose acetate butyrate having an acyl group having 2 to 4 carbon atoms as a substituent.
　アシル基で置換されていない部分は通常ヒドロキシル基（水酸基）として存在しているものである。これらは公知の方法で合成することができる。 The portion not substituted with an acyl group is usually present as a hydroxyl group (hydroxyl group). These can be synthesized by known methods.
　なお、アセチル基の置換度や他のアシル基の置換度は、ＡＳＴＭ－Ｄ８１７－９６に規定の方法により求めたものである。 Incidentally, the substitution degree of the acetyl group and the substitution degree of other acyl groups were determined by the method prescribed in ASTM-D817-96.
　本発明に係るセルロースエステル樹脂の重量平均分子量（Ｍｗ）は、７５０００以上であれば、１００００００程度のものであっても本発明に係る目的を達成することができるが、生産性を考慮すると７５０００～２８００００のものが好ましく、１０００００～２４００００のものが更に好ましい。この重量平均分子量の測定は、前述のＧＰＣ法によってすることができる。 If the weight average molecular weight (Mw) of the cellulose ester resin according to the present invention is 75,000 or more, the object according to the present invention can be achieved even if the weight average molecular weight (Mw) is about 1,000,000. Those having 280000 are preferred, and those having 100,000 to 240,000 are more preferred. This weight average molecular weight can be measured by the GPC method described above.
　〈アクリル粒子〉
　本発明においては、アクリル樹脂含有フィルムにアクリル粒子を含有させてもよい。 <Acrylic particles>
In the present invention, the acrylic resin-containing film may contain acrylic particles.
　本発明に係るアクリル粒子は、前記アクリル樹脂及びセルロースエステル樹脂とアクリル樹脂含有フィルム中で粒子の状態で存在すること（非相溶状態ともいう）が特徴である。 The acrylic particles according to the present invention are characterized by being present in the state of particles in the acrylic resin, cellulose ester resin and acrylic resin-containing film (also referred to as incompatible state).
　上記アクリル粒子は、例えば、作製したアクリル樹脂含有フィルムを所定量採取し、溶媒に溶解させて攪拌し、充分に溶解・分散させたところで、アクリル粒子の平均粒子径未満の孔径を有するＰＴＦＥ製のメンブレンフィルターを用いて濾過し、濾過捕集された不溶物の重さが、アクリル樹脂含有フィルムに添加したアクリル粒子の９０質量％以上あることが好ましい。 The acrylic particles are obtained by, for example, collecting a predetermined amount of the prepared acrylic resin-containing film, dissolving in a solvent, stirring, and sufficiently dissolving and dispersing the PTFE film having a pore diameter less than the average particle diameter of the acrylic particles. It is preferable that the weight of the insoluble matter filtered and collected using the membrane filter is 90% by mass or more of the acrylic particles added to the acrylic resin-containing film.
　本発明に用いられるアクリル粒子は特に限定されるものではないが、２層以上の層構造を有するアクリル粒子であることが好ましく、特に下記多層構造アクリル系粒状複合体であることが好ましい。 The acrylic particles used in the present invention are not particularly limited, but are preferably acrylic particles having a layer structure of two or more layers, and particularly preferably the following multilayer structure acrylic granular composite.
　多層構造アクリル系粒状複合体とは、中心部から外周部に向かって最内硬質層重合体、ゴム弾性を示す架橋軟質層重合体、及び最外硬質層重合体が、層状に重ね合わされてなる構造を有する粒子状のアクリル系重合体を言う。 The multilayer structure acrylic granular composite is formed by laminating the innermost hard layer polymer, the cross-linked soft layer polymer exhibiting rubber elasticity, and the outermost hard layer polymer from the central portion toward the outer peripheral portion. This refers to a particulate acrylic polymer having a structure.
　本発明に係るアクリル系樹脂組成物に用いられる多層構造アクリル系粒状複合体の好ましい態様としては、以下の様なものが挙げられる。
（ａ）メチルメタクリレート８０～９８．９質量％、アルキル基の炭素数が１～８のアルキルアクリレート１～２０質量％、及び多官能性グラフト剤０．０１～０．３質量％からなる単量体混合物を重合して得られる最内硬質層重合体、
（ｂ）上記最内硬質層重合体の存在下に、アルキル基の炭素数が４～８のアルキルアクリレート７５～９８．５質量％、多官能性架橋剤０．０１～５質量％及び多官能性グラフト剤０．５～５質量％からなる単量体混合物を重合して得られる架橋軟質層重合体、
（ｃ）上記最内硬質層及び架橋軟質層からなる重合体の存在下に、メチルメタクリレート８０～９９質量％とアルキル基の炭素数が１～８であるアルキルアクリレート１～２０質量％とからなる単量体混合物を重合して得られる最外硬層重合体、
よりなる３層構造を有し、かつ得られた３層構造重合体が最内硬質層重合体（ａ）５～４０質量％、軟質層重合体（ｂ）３０～６０質量％、及び最外硬質層重合体（ｃ）２０～５０質量％からなり、アセトンで分別したときに不溶部があり、その不溶部のメチルエチルケトン膨潤度が１．５～４．０であるアクリル系粒状複合体、が挙げられる。 Preferred embodiments of the multilayer structure acrylic granular composite used in the acrylic resin composition according to the present invention include the following.
(A) Monomer comprising 80 to 98.9% by mass of methyl methacrylate, 1 to 20% by mass of alkyl acrylate having 1 to 8 carbon atoms in the alkyl group, and 0.01 to 0.3% by mass of polyfunctional grafting agent Innermost hard layer polymer obtained by polymerizing the body mixture,
(B) In the presence of the innermost hard layer polymer, 75 to 98.5% by mass of an alkyl acrylate having 4 to 8 carbon atoms in the alkyl group, 0.01 to 5% by mass of a polyfunctional crosslinking agent, and polyfunctional Cross-linked soft layer polymer obtained by polymerizing a monomer mixture comprising 0.5 to 5% by weight of a grafting agent,
(C) In the presence of the polymer composed of the innermost hard layer and the crosslinked soft layer, it is composed of 80 to 99% by mass of methyl methacrylate and 1 to 20% by mass of alkyl acrylate in which the alkyl group has 1 to 8 carbon atoms. Outermost hard layer polymer obtained by polymerizing the monomer mixture,
And the obtained three-layer structure polymer has an innermost hard layer polymer (a) of 5 to 40% by mass, a soft layer polymer (b) of 30 to 60% by mass, and an outermost layer polymer. A hard layer polymer (c) comprising 20 to 50% by mass, having an insoluble part when fractionated with acetone, and an acrylic granular composite having a methyl ethyl ketone swelling degree of 1.5 to 4.0 in the insoluble part, Can be mentioned.
　なお、特公昭６０－１７４０６号あるいは特公平３－３９０９５号において開示されている様に、多層構造アクリル系粒状複合体の各層の組成や粒子径を規定しただけでなく、多層構造アクリル系粒状複合体の引張り弾性率やアセトン不溶部のメチルエチルケトン膨潤度を特定範囲内に設定することにより、さらに充分な耐衝撃性と耐応力白化性のバランスを実現することが可能となる。 As disclosed in Japanese Patent Publication No. 60-17406 or Japanese Patent Publication No. 3-39095, not only the composition and particle diameter of each layer of the multilayered acrylic granular composite are defined, but also the multilayered acrylic granular composite. By setting the tensile modulus of the body and the degree of swelling of methyl ethyl ketone in the acetone-insoluble part within a specific range, it is possible to realize a further sufficient balance between impact resistance and stress whitening resistance.
　ここで、多層構造アクリル系粒状複合体を構成する最内硬質層重合体（ａ）は、メチルメタクリレート８０～９８．９質量％、アルキル基の炭素数が１～８のアルキルアクリレート１～２０質量％及び多官能性グラフト剤０．０１～０．３質量％からなる単量体混合物を重合して得られるものが好ましい。 Here, the innermost hard layer polymer (a) constituting the multilayer structure acrylic granular composite is 80 to 98.9% by mass of methyl methacrylate and 1 to 20 mass of alkyl acrylate having 1 to 8 carbon atoms in the alkyl group. % And a monomer mixture consisting of 0.01 to 0.3% by mass of a polyfunctional grafting agent is preferred.
　ここで、アルキル基の炭素数が１～８のアルキルアクリレートとしては、メチルアクリレート、エチルアクリレート、ｎ－プロピルアクリレート、ｎ－ブチルアクリレート、ｓ－ブチルアクリレート、２－エチルヘキシルアクリレート等が挙げられ、メチルアクリレートやｎ－ブチルアクリレートが好ましく用いられる。 Here, examples of the alkyl acrylate having 1 to 8 carbon atoms in the alkyl group include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, s-butyl acrylate, 2-ethylhexyl acrylate, and the like. And n-butyl acrylate are preferably used.
　最内硬質層重合体（ａ）におけるアルキルアクリレート単位の割合は１～２０質量％であり、該単位が１質量％未満では、重合体の熱分解性が大きくなり、一方、該単位が２０質量％を越えると、最内硬質層重合体（ｃ）のガラス転移温度が低くなり、３層構造アクリル系粒状複合体の耐衝撃性付与効果が低下するので、いずれも好ましくない。 The proportion of the alkyl acrylate unit in the innermost hard layer polymer (a) is 1 to 20% by mass. When the unit is less than 1% by mass, the thermal decomposability of the polymer is increased, while the unit is 20% by mass. If it exceeds 50%, the glass transition temperature of the innermost hard layer polymer (c) is lowered, and the impact resistance imparting effect of the three-layer structure acrylic granular composite is lowered.
　多官能性グラフト剤としては、異なる重合可能な官能基を有する多官能性単量体、例えば、アクリル酸、メタクリル酸、マレイン酸、フマル酸のアリルエステル等が挙げられ、アリルメタクリレートが好ましく用いられる。 Examples of the polyfunctional grafting agent include polyfunctional monomers having different polymerizable functional groups, such as allyl esters of acrylic acid, methacrylic acid, maleic acid, and fumaric acid, and allyl methacrylate is preferably used. .
　多官能性グラフト剤は、最内硬質層重合体と軟質層重合体を化学的に結合するために用いられ、その最内硬質層重合時に用いる割合は０．０１～０．３質量％である。 The polyfunctional grafting agent is used to chemically bond the innermost hard layer polymer and the soft layer polymer, and the ratio used during the innermost hard layer polymerization is 0.01 to 0.3% by mass. .
　アクリル系粒状複合体を構成する架橋軟質層重合体（ｂ）は、上記最内硬質層重合体（ａ）の存在下に、アルキル基の炭素数が１～８のアルキルアクリレート７５～９８．５質量％、多官能性架橋剤０．０１～５質量％及び多官能性グラフト剤０．５～５質量％からなる単量体混合物を重合して得られるものが好ましい。 The crosslinked soft layer polymer (b) constituting the acrylic granular composite is an alkyl acrylate having from 9 to 8 carbon atoms having an alkyl group of 1 to 8 in the presence of the innermost hard layer polymer (a). What is obtained by polymerizing a monomer mixture consisting of 10% by mass, 0.01 to 5% by mass of a polyfunctional crosslinking agent and 0.5 to 5% by mass of a polyfunctional grafting agent is preferred.
　ここで、アルキル基の炭素数が４～８のアルキルアクリレートとしては、ｎ－ブチルアクリレートや２－エチルヘキシルアクリレートが好ましく用いられる。 Here, n-butyl acrylate or 2-ethylhexyl acrylate is preferably used as the alkyl acrylate having 4 to 8 carbon atoms in the alkyl group.
　また、これらの重合性単量体と共に、２５質量％以下の共重合可能な他の単官能性単量体を共重合させることも可能である。 In addition to these polymerizable monomers, it is possible to copolymerize 25% by mass or less of other monofunctional monomers capable of copolymerization.
　共重合可能な他の単官能性単量体としては、スチレン及び置換スチレン誘導体が挙げられる。アルキル基の炭素数が４～８のアルキルアクリレートとスチレンとの比率は、前者が多いほど生成重合体（ｂ）のガラス転移温度が低下し、即ち軟質化できるのである。 Examples of other monofunctional monomers that can be copolymerized include styrene and substituted styrene derivatives. As the ratio of the alkyl acrylate having 4 to 8 carbon atoms in the alkyl group and styrene increases, the glass transition temperature of the produced polymer (b) decreases as the former increases, that is, it can be softened.
　一方、樹脂組生物の透明性の観点からは、軟質層重合体（ｂ）の常温での屈折率を最内硬質層重合体（ａ）、最外硬質層重合体（ｃ）、及び硬質熱可塑性アクリル樹脂に近づけるほうが有利であり、これらを勘案して両者の比率を選定する。 On the other hand, from the viewpoint of the transparency of the resin assembly, the refractive index of the soft layer polymer (b) at room temperature is set to the innermost hard layer polymer (a), the outermost hard layer polymer (c), and the hard heat. It is more advantageous to make it closer to the plastic acrylic resin, and the ratio between them is selected in consideration of these.
　例えば、被覆層厚さの小さな用途においては、必ずしもスチレンを共重合しなくとも良い。 For example, in applications where the coating layer thickness is small, it is not always necessary to copolymerize styrene.
　多官能性グラフト剤としては、前記の最内層硬質重合体（ａ）の項で挙げたものを用いることができる。ここで用いる多官能性グラフト剤は、軟質層重合体（ｂ）と最外硬質層重合体（ｃ）を化学的に結合するために用いられ、その最内硬質層重合時に用いる割合は耐衝撃性付与効果の観点から０．５～５質量％が好ましい。 As the polyfunctional grafting agent, those mentioned in the section of the innermost layer hard polymer (a) can be used. The polyfunctional grafting agent used here is used to chemically bond the soft layer polymer (b) and the outermost hard layer polymer (c), and the proportion used during the innermost hard layer polymerization is impact resistance. From the viewpoint of the effect of imparting properties, 0.5 to 5% by mass is preferable.
　多官能性架橋剤としては、ジビニル化合物、ジアリル化合物、ジアクリル化合物、ジメタクリル化合物などの一般に知られている架橋剤が使用できるが、ポリエチレングリコールジアクリレート（分子量２００～６００）が好ましく用いられる。 As the polyfunctional crosslinking agent, generally known crosslinking agents such as divinyl compounds, diallyl compounds, diacrylic compounds, dimethacrylic compounds and the like can be used, but polyethylene glycol diacrylate (molecular weight 200 to 600) is preferably used.
　ここで用いる多官能性架橋剤は、軟質層（ｂ）の重合時に架橋構造を生成し、耐衝撃性付与の効果を発現させるために用いられる。ただし、先の多官能性グラフト剤を軟質層の重合時に用いれば、ある程度は軟質層（ｂ）の架橋構造を生成するので、多官能性架橋剤は必須成分ではないが、多官能性架橋剤を軟質層重合時に用いる割合は耐衝撃性付与効果の観点から０．０１～５質量％が好ましい。 The polyfunctional cross-linking agent used here is used to generate a cross-linked structure during the polymerization of the soft layer (b) and to exhibit the effect of imparting impact resistance. However, if the above-mentioned polyfunctional grafting agent is used during the polymerization of the soft layer, the polyfunctional crosslinking agent is not an essential component because the crosslinked structure of the soft layer (b) is generated to some extent. Is preferably 0.01 to 5% by weight from the viewpoint of imparting impact resistance.
　多層構造アクリル系粒状複合体を構成する最外硬質層重合体（ｃ）は、上記最内硬質層重合体（ａ）及び軟質層重合体（ｂ）の存在下に、メチルメタクリレート８０～９９質量％及びアルキル基の炭素数が１～８であるアルキルアクリレート１～２０質量％からなる単量体混合物を重合して得られるものが好ましい。 The outermost hard layer polymer (c) constituting the multilayer structure acrylic granular composite is 80 to 99 mass% of methyl methacrylate in the presence of the innermost hard layer polymer (a) and the soft layer polymer (b). % And a monomer mixture comprising 1 to 20% by mass of an alkyl acrylate having 1 to 8 carbon atoms in the alkyl group is preferred.
　ここで、アルキルアクリレートとしては、前述したものが用いられるが、メチルアクリレートやエチルアクリレートが好ましく用いられる。 Here, as the alkyl acrylate, those described above are used, but methyl acrylate and ethyl acrylate are preferably used.
　最外硬質層（ｃ）におけるアルキルアクリレート単位の割合は、１～２０質量％が好ましい。 The proportion of alkyl acrylate units in the outermost hard layer (c) is preferably 1 to 20% by mass.
　また、最外硬質層（ｃ）の重合時に、アクリル樹脂との相溶性向上を目的として、分子量を調節するためアルキルメルカプタン等を連鎖移動剤として用い、実施することも可能である。 Also, during the polymerization of the outermost hard layer (c), an alkyl mercaptan or the like can be used as a chain transfer agent to adjust the molecular weight for the purpose of improving compatibility with the acrylic resin.
　とりわけ、最外硬質層に、分子量が内側から外側へ向かって次第に小さくなるような勾配を設けることは、伸びと耐衝撃性のバランスを改良するうえで好ましい。具体的な方法としては、最外硬質層を形成するための単量体混合物を２つ以上に分割し、各回ごとに添加する連鎖移動剤量を順次増加するような手法によって、分子量を内側から外側へ向かって小さくすることが可能である。 In particular, it is preferable to provide the outermost hard layer with a gradient such that the molecular weight gradually decreases from the inside toward the outside in order to improve the balance between elongation and impact resistance. As a specific method, the monomer mixture for forming the outermost hard layer is divided into two or more, and the molecular weight is increased from the inside by a method of sequentially increasing the amount of chain transfer agent added each time. It is possible to make it smaller toward the outside.
　この際に形成される分子量は、各回に用いられる単量体混合物をそれ単独で同条件にて重合し、得られた重合体の分子量を測定することによって調べることもできる。 The molecular weight formed at this time can also be examined by polymerizing the monomer mixture used each time under the same conditions, and measuring the molecular weight of the obtained polymer.
　本発明に好ましく用いられる多層構造重合体であるアクリル系粒状複合体の粒子径については、特に限定されるものではないが、１０ｎｍ以上、１０００ｎｍ以下であることが好ましく、さらに、２０ｎｍ以上、５００ｎｍ以下であることがより好ましく、特に５０ｎｍ以上、４００ｎｍ以下であることが最も好ましい。 The particle diameter of the acrylic granular composite which is a multilayer structure polymer preferably used in the present invention is not particularly limited, but is preferably 10 nm or more and 1000 nm or less, and more preferably 20 nm or more and 500 nm or less. More preferably, it is most preferably 50 nm or more and 400 nm or less.
　本発明に好ましく用いられる多層構造重合体であるアクリル系粒状複合体において、コアとシェルの質量比は、特に限定されるものではないが、多層構造重合体全体を１００質量部としたときに、コア層が５０質量部以上、９０質量部以下であることが好ましく、さらに、６０質量部以上、８０質量部以下であることがより好ましい。 In the acrylic granular composite that is a multilayer structure polymer preferably used in the present invention, the mass ratio of the core and the shell is not particularly limited, but when the entire multilayer structure polymer is 100 parts by mass, The core layer is preferably 50 parts by mass or more and 90 parts by mass or less, and more preferably 60 parts by mass or more and 80 parts by mass or less.
　このような多層構造アクリル系粒状複合体の市販品の例としては、例えば、三菱レイヨン（株）製“メタブレン”、鐘淵化学工業（株）製“カネエース”、呉羽化学工業（株）製“パラロイド”、ロームアンドハース（株）製“アクリロイド”、ガンツ化成工業（株）製“スタフィロイド”及びクラレ（株）製“パラペットＳＡ”などが挙げられ、これらは、単独ないし２種以上を用いることができる。 Examples of such a commercial product of a multilayer structure acrylic granular composite include, for example, “Metablene” manufactured by Mitsubishi Rayon Co., Ltd., “Kaneace” manufactured by Kaneka Chemical Co., Ltd., “Kaneha Chemical Co., Ltd.” Paraloid ”,“ Acryloid ”manufactured by Rohm and Haas Co., Ltd.,“ Staffyroid ”manufactured by Ganz Kasei Kogyo Co., Ltd.,“ Parapet SA ”manufactured by Kuraray Co., Ltd. and the like are used alone or in combination of two or more. be able to.
　また、本発明に好ましく用いられるアクリル粒子として好適に使用されるグラフト共重合体であるアクリル粒子（ｃ－１）の具体例としては、ゴム質重合体の存在下に、不飽和カルボン酸エステル系単量体、不飽和カルボン酸系単量体、芳香族ビニル系単量体、及び必要に応じてこれらと共重合可能な他のビニル系単量体からなる単量体混合物を共重合せしめたグラフト共重合体が挙げられる。 Further, specific examples of the acrylic particles (c-1) which are graft copolymers preferably used as the acrylic particles preferably used in the present invention include unsaturated carboxylic acid ester series in the presence of a rubbery polymer. A monomer mixture comprising a monomer, an unsaturated carboxylic acid monomer, an aromatic vinyl monomer, and, if necessary, other vinyl monomers copolymerizable therewith was copolymerized. A graft copolymer is mentioned.
　グラフト共重合体であるアクリル粒子（ｃ－１）に用いられるゴム質重合体には特に制限はないが、ジエン系ゴム、アクリル系ゴム及びエチレン系ゴムなどが使用できる。 The rubbery polymer used for the acrylic particles (c-1) as the graft copolymer is not particularly limited, but diene rubber, acrylic rubber, ethylene rubber, and the like can be used.
　具体例としては、ポリブタジエン、スチレン－ブタジエン共重合体、スチレン－ブタジエンのブロック共重合体、アクリロニトリル－ブタジエン共重合体、アクリル酸ブチル－ブタジエン共重合体、ポリイソプレン、ブタジエン－メタクリル酸メチル共重合体、アクリル酸ブチル－メタクリル酸メチル共重合体、ブタジエン－アクリル酸エチル共重合体、エチレン－プロピレン共重合体、エチレン－プロピレン－ジエン系共重合体、エチレン－イソプレン共重合体、及びエチレン－アクリル酸メチル共重合体などが挙げられる。 Specific examples include polybutadiene, styrene-butadiene copolymer, block copolymer of styrene-butadiene, acrylonitrile-butadiene copolymer, butyl acrylate-butadiene copolymer, polyisoprene, butadiene-methyl methacrylate copolymer. Butyl acrylate-methyl methacrylate copolymer, butadiene-ethyl acrylate copolymer, ethylene-propylene copolymer, ethylene-propylene-diene copolymer, ethylene-isoprene copolymer, and ethylene-acrylic acid Examples thereof include a methyl copolymer.
　これらのゴム質重合体は、１種又は２種以上の混合物で使用することが可能である。 These rubbery polymers can be used alone or in a mixture of two or more.
　また、アクリル樹脂及びアクリル粒子のそれぞれの屈折率が近似している場合、本発明に係るアクリル樹脂含有フィルムの透明性を得ることができるため、好ましい。 Further, it is preferable that the refractive indexes of the acrylic resin and the acrylic particles are close to each other because the transparency of the acrylic resin-containing film according to the present invention can be obtained.
　具体的には、アクリル粒子とアクリル樹脂の屈折率差が０．０５以下であることが好ましく、より好ましくは０．０２以下、とりわけ０．０１以下であることが好ましい。 Specifically, the refractive index difference between the acrylic particles and the acrylic resin is preferably 0.05 or less, more preferably 0.02 or less, and particularly preferably 0.01 or less.
　このような屈折率条件を満たすためには、アクリル樹脂の各単量体単位組成比を調整する方法、及び／又はアクリル粒子に使用されるゴム質重合体あるいは単量体の組成比を調製する方法などにより、屈折率差を小さくすることができ、透明性に優れたアクリル樹脂含有フィルムを得ることができる。 In order to satisfy such a refractive index condition, a method for adjusting the composition ratio of each monomer unit of the acrylic resin and / or a composition ratio of the rubbery polymer or monomer used for the acrylic particles is prepared. Depending on the method, the difference in refractive index can be reduced, and an acrylic resin-containing film excellent in transparency can be obtained.
　尚、ここでいう屈折率差とは、アクリル樹脂が可溶な溶媒に、本発明に係るアクリル樹脂含有フィルムを適当な条件で十分に溶解させ白濁溶液とし、これを遠心分離等の操作により、溶媒可溶部分と不溶部分に分離し、この可溶部分（アクリル樹脂）と不溶部分（アクリル粒子）をそれぞれ精製した後、測定した屈折率（２３℃、測定波長：５５０ｎｍ）の差を示す。 In addition, the refractive index difference here is a solution in which the acrylic resin-containing film according to the present invention is sufficiently dissolved in an appropriate condition in a solvent in which the acrylic resin is soluble to obtain a cloudy solution, which is subjected to an operation such as centrifugation. The solvent is separated into a soluble part and an insoluble part, and after the soluble part (acrylic resin) and the insoluble part (acrylic particles) are purified, the difference in measured refractive index (23 ° C., measurement wavelength: 550 nm) is shown.
　本発明においてアクリル樹脂）に、アクリル粒子を配合する方法には、特に制限はなく、アクリル樹脂とその他の任意成分を予めブレンドした後、通常２００～３５０℃において、アクリル粒子を添加しながら一軸又は二軸押出機により均一に溶融混練する方法が、複数のアクリル粒子の凝集を回避して透明性に優れる観点で好ましく用いられる。 The method of blending the acrylic particles with the acrylic resin in the present invention is not particularly limited, and after blending the acrylic resin and other optional components in advance, usually at 200 to 350 ° C. while adding the acrylic particles, the uniaxial or A method of uniformly melt-kneading with a twin-screw extruder is preferably used from the viewpoint of excellent transparency by avoiding aggregation of a plurality of acrylic particles.
　また、アクリル粒子を予め分散した溶液を、アクリル樹脂、及びセルロースエステル樹脂を溶解した溶液（ドープ液）に添加して混合する方法や、アクリル粒子及びその他の任意の添加剤を溶解、混合した溶液をインライン添加する等の方法を用いることができる。 In addition, a method in which a solution in which acrylic particles are dispersed in advance is added to and mixed with a solution (dope solution) in which an acrylic resin and a cellulose ester resin are dissolved, and a solution in which acrylic particles and other optional additives are dissolved and mixed. A method such as in-line addition can be used.
　本発明に係るアクリル粒子としては、市販のものも使用することができる。例えば、メタブレンＷ－３４１（Ｃ２）（三菱レイヨン（株）製）を、ケミスノーＭＲ－２Ｇ（Ｃ３）、ＭＳ－３００Ｘ（Ｃ４）（綜研化学（株）製）等を挙げることができる。 Commercially available acrylic particles can also be used as the acrylic particles according to the present invention. For example, metabrene W-341 (C2) (manufactured by Mitsubishi Rayon Co., Ltd.), Chemisnow MR-2G (C3), MS-300X (C4) (manufactured by Soken Chemical Co., Ltd.) and the like can be mentioned.
　本発明に係るアクリル樹脂含有フィルムにおいて、該フィルムを構成する樹脂の総質量に対して、０．５～４５質量％のアクリル粒子を含有することが好ましい。 The acrylic resin-containing film according to the present invention preferably contains 0.5 to 45% by mass of acrylic particles with respect to the total mass of the resin constituting the film.
　〈第１光学異方性層のその他の添加剤〉
　本発明に係るアクリル樹脂含有フィルムにおいては、組成物の流動性や柔軟性を向上することに加えて、透湿度を制御する目的で、透湿度抑制剤を併用することも可能である。 <Other additives for the first optically anisotropic layer>
In the acrylic resin containing film which concerns on this invention, in addition to improving the fluidity | liquidity and softness | flexibility of a composition, it is also possible to use a moisture permeability inhibitor together in order to control moisture permeability.
　透湿度抑制剤としては、フタル酸エステル系、脂肪酸エステル系、トリメリット酸エステル系、リン酸エステル系、ポリエステル系、あるいはエポキシ系等が挙げられる。 Examples of the moisture permeability inhibitor include phthalate ester, fatty acid ester, trimellitic ester, phosphoric ester, polyester, and epoxy.
　この中で、ポリエステル系とフタル酸エステル系の透湿度抑制剤が好ましく用いられる。ポリエステル系透湿度抑制剤は、フタル酸ジオクチルなどのフタル酸エステル系の透湿度抑制剤に比べて非移行性や耐抽出性に優れる。　従って、用途に応じてこれらの透湿度抑制剤を選択、あるいは併用することによって、広範囲の用途に適用できる。 Of these, polyester and phthalate ester moisture permeability inhibitors are preferably used. Polyester moisture permeability inhibitors are superior in non-migration and extraction resistance compared to phthalate ester moisture permeability inhibitors such as dioctyl phthalate. Therefore, it is applicable to a wide range of uses by selecting or using these moisture permeability inhibitors according to the use.
　ポリエステル系透湿度抑制剤は、一価ないし四価のカルボン酸と一価ないし六価のアルコールとの反応物であるが、主に二価カルボン酸とグリコールとを反応させて得られたものが用いられる。 The polyester-based moisture permeability inhibitor is a reaction product of a monovalent or tetravalent carboxylic acid and a monovalent or hexavalent alcohol, and is mainly obtained by reacting a divalent carboxylic acid with a glycol. Used.
　代表的な二価カルボン酸としては、グルタル酸、イタコン酸、アジピン酸、フタル酸、アゼライン酸、セバシン酸などが挙げられる。 Representative divalent carboxylic acids include glutaric acid, itaconic acid, adipic acid, phthalic acid, azelaic acid, sebacic acid and the like.
　特に、アジピン酸、フタル酸などを用いると可塑化特性に優れたものが得られる。グリコールとしてはエチレン、プロピレン、１，３－ブチレン、１，４－ブチレン、１，６－ヘキサメチレン、ネオペンチレン、ジエチレン、トリエチレン、ジプロピレンなどのグリコールが挙げられる。これらの二価カルボン酸及びグリコールはそれぞれ単独で、あるいは混合して使用してもよい。 In particular, when adipic acid, phthalic acid, or the like is used, those having excellent plasticizing properties can be obtained. Examples of the glycol include glycols such as ethylene, propylene, 1,3-butylene, 1,4-butylene, 1,6-hexamethylene, neopentylene, diethylene, triethylene, and dipropylene. These divalent carboxylic acids and glycols may be used alone or in combination.
　このエステル系の透湿度抑制剤はエステル、オリゴエステル、ポリエステルの型のいずれでもよく、分子量は１００～１００００の範囲が良いが、好ましくは６００～３０００の範囲が、より可塑化効果が大きい。 The ester-based moisture permeation suppressor may be any of ester, oligoester, and polyester types, and the molecular weight is preferably in the range of 100 to 10,000, and more preferably in the range of 600 to 3000, which has a greater plasticizing effect.
　また、透湿度抑制剤の粘度は分子構造や分子量と相関があるが、アジピン酸系透湿度抑制剤の場合相溶性、可塑化効率の関係から２００～５０００ｍＰａ・ｓ（２５℃）の範囲が良い。さらに、いくつかのポリエステル系透湿度抑制剤を併用してもかまわない。 In addition, the viscosity of the moisture permeability inhibitor has a correlation with the molecular structure and molecular weight, but in the case of an adipic acid moisture permeability inhibitor, a range of 200 to 5000 mPa · s (25 ° C.) is preferable in view of compatibility and plasticization efficiency. . Further, some polyester moisture permeability inhibitors may be used in combination.
　透湿度抑制剤はアクリル樹脂を含有する組成物１００質量部に対して、０．５～３０質量部を添加するのが好ましい。透湿度抑制剤の添加量が３０質量部を越えると、表面がべとつくので、実用上好ましくない。 The moisture permeability inhibitor is preferably added in an amount of 0.5 to 30 parts by mass with respect to 100 parts by mass of the composition containing an acrylic resin. If the amount of the moisture permeability inhibitor exceeds 30 parts by mass, the surface becomes sticky, which is not preferable for practical use.
　本願の目的を満たす意味で、第１光学異方性層を構成するフィルムの６０℃、９５％ＲＨにおける透湿度は２０～６００ｇ／ｍ２・２４ｈの範囲であることを要する。このとき、透湿度抑制剤を上記範囲で添加すること、アクリル樹脂に対して、アクリル樹脂の透湿度を増加させる目的で、セルロースエステル樹脂を透湿度向上剤として選択して上述の組成の範囲で調節して相溶させることで、フィルムの透湿度を調節することができる。 In order to satisfy the object of the present application, the moisture permeability at 60 ° C. and 95% RH of the film constituting the first optically anisotropic layer needs to be in the range of 20 to 600 g / m 2 · 24 h. At this time, for the purpose of increasing the moisture permeability of the acrylic resin relative to the acrylic resin by adding the moisture permeability inhibitor in the above range, the cellulose ester resin is selected as the moisture permeability improving agent within the above composition range. By adjusting and making it compatible, the water vapor transmission rate of a film can be adjusted.
　本発明の第２光学異方性層に用いるセルロースエステル樹脂と第１光学異方性層に用いるセルロースエステル樹脂は、第２光学異方性層及び第１光学異方性層の各々の目的を満たす範囲で選択することができ、これらは同じであっても異なっていてもよい。 The cellulose ester resin used for the second optically anisotropic layer and the cellulose ester resin used for the first optically anisotropic layer of the present invention have the respective purposes of the second optically anisotropic layer and the first optically anisotropic layer. They can be selected within the range to be satisfied, and these may be the same or different.
　本発明に係るアクリル樹脂を含有する組成物は紫外線吸収剤を含有することも好ましく、用いられる紫外線吸収剤としては、ベンゾトリアゾール系、２－ヒドロキシベンゾフェノン系又はサリチル酸フェニルエステル系のもの等が挙げられる。 The composition containing the acrylic resin according to the present invention preferably contains an ultraviolet absorber, and examples of the ultraviolet absorber used include benzotriazole, 2-hydroxybenzophenone, or salicylic acid phenyl ester. .
　例えば、２－（５－メチル－２－ヒドロキシフェニル）ベンゾトリアゾール、２－［２－ヒドロキシ－３，５－ビス（α，α－ジメチルベンジル）フェニル］－２Ｈ－ベンゾトリアゾール、２－（３，５－ジ－ｔ－ブチル－２－ヒドロキシフェニル）ベンゾトリアゾール等のトリアゾール類、２－ヒドロキシ－４－メトキシベンゾフェノン、２－ヒドロキシ－４－オクトキシベンゾフェノン、２，２’－ジヒドロキシ－４－メトキシベンゾフェノン等のベンゾフェノン類を例示することができる。 For example, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3 Triazoles such as 5-di-t-butyl-2-hydroxyphenyl) benzotriazole, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone And benzophenones.
　ここで、紫外線吸収剤のうちでも、分子量が４００以上の紫外線吸収剤は、高沸点で揮発しにくく、高温成形時にも飛散しにくいため、比較的少量の添加で効果的に耐候性を改良することができる。 Here, among ultraviolet absorbers, ultraviolet absorbers having a molecular weight of 400 or more are less likely to volatilize at a high boiling point and are difficult to disperse even during high-temperature molding, so that the weather resistance is effectively improved with a relatively small amount of addition. be able to.
　また、特に薄い被覆層から基板層への移行性も小さく、積層板の表面にも析出しにくいため、含有された紫外線吸収剤量が長時間維持され、耐候性改良効果の持続性に優れるなどの点から好ましい。 In addition, since the transition from the thin coating layer to the substrate layer is particularly small and hardly precipitates on the surface of the laminate, the amount of contained UV absorber is maintained for a long time, and the durability of the weather resistance improvement effect is excellent. From the point of view, it is preferable.
　分子量が４００以上の紫外線吸収剤としては、２－［２－ヒドロキシ－３，５－ビス（α，α－ジメチルベンジル）フェニル］－２－ベンゾトリアゾール、２，２－メチレンビス［４－（１，１，３，３－テトラブチル）－６－（２Ｈ－ベンゾトリアゾール－２－イル）フェノール］等のベンゾトリアゾール系、ビス（２，２，６，６－テトラメチル－４－ピペリジル）セバケート、ビス（１，２，２，６，６－ペンタメチル－４－ピペリジル）セバケート等のヒンダードアミン系、さらには２－（３，５－ジ－ｔ－ブチル－４－ヒドロキシベンジル）－２－ｎ－ブチルマロン酸ビス（１，２，２，６，６－ペンタメチル－４－ピペリジル）、１－［２－［３－（３，５－ジ－ｔ－ブチル－４－ヒドロキシフェニル）プロピオニルオキシ］エチル］－４－［３－（３，５－ジ－ｔ－ブチル－４－ヒドロキシフェニル）プロピオニルオキシ］－２，２，６，６－テトラメチルピペリジン等の分子内にヒンダードフェノールとヒンダードアミンの構造を共に有するハイブリッド系のものが挙げられる。 Examples of the ultraviolet absorber having a molecular weight of 400 or more include 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2-benzotriazole, 2,2-methylenebis [4- (1, 1,3,3-tetrabutyl) -6- (2H-benzotriazol-2-yl) phenol], bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis ( Hindered amines such as 1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and 2- (3,5-di-t-butyl-4-hydroxybenzyl) -2-n-butylmalonic acid Bis (1,2,2,6,6-pentamethyl-4-piperidyl), 1- [2- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] Such as til] -4- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine A hybrid system having both structures is exemplified.
　これらは単独で、あるいは２種以上を併用して使用することができる。これらのうちでも、２－［２－ヒドロキシ－３，５－ビス（α，α－ジメチルベンジル）フェニル］－２－ベンゾトリアゾールや２，２－メチレンビス［４－（１，１，３，３－テトラブチル）－６－（２Ｈ－ベンゾトリアゾール－２－イル）フェノール］が特に好ましい。 These can be used alone or in combination of two or more. Among these, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2-benzotriazole and 2,2-methylenebis [4- (1,1,3,3- Tetrabutyl) -6- (2H-benzotriazol-2-yl) phenol] is particularly preferred.
　さらに、本発明に係るアクリル樹脂含有フィルムに用いられるアクリル樹脂には成形加工時の熱分解性や熱着色性を改良するために各種の酸化防止剤を添加することもできる。 Furthermore, various antioxidants may be added to the acrylic resin used in the acrylic resin-containing film according to the present invention in order to improve the thermal decomposability and thermal colorability during molding.
　また帯電防止剤を加えて、アクリル樹脂含有フィルムに帯電防止性能を与えることも可能である。 It is also possible to add an antistatic agent to impart antistatic performance to the acrylic resin-containing film.
　本発明に係るアクリル樹脂組成物として、リン系難燃剤を配合した難燃アクリル系樹脂組成物を用いても良い。 As the acrylic resin composition according to the present invention, a flame retardant acrylic resin composition containing a phosphorus flame retardant may be used.
　ここで用いられるリン系難燃剤としては、赤リン、トリアリールリン酸エステル、ジアリールリン酸エステル、モノアリールリン酸エステル、アリールホスホン酸化合物、アリールホスフィンオキシド化合物、縮合アリールリン酸エステル、ハロゲン化アルキルリン酸エステル、含ハロゲン縮合リン酸エステル、含ハロゲン縮合ホスホン酸エステル、含ハロゲン亜リン酸エステル等から選ばれる１種、あるいは２種以上の混合物を挙げることができる。 Phosphorus flame retardants used here include red phosphorus, triaryl phosphate ester, diaryl phosphate ester, monoaryl phosphate ester, aryl phosphonate compound, aryl phosphine oxide compound, condensed aryl phosphate ester, halogenated alkyl phosphorus. Examples thereof include one or a mixture of two or more selected from acid esters, halogen-containing condensed phosphates, halogen-containing condensed phosphonates, halogen-containing phosphites, and the like.
　具体的な例としては、トリフェニルホスフェート、９，１０－ジヒドロ－９－オキサ－１０－ホスファフェナンスレン－１０－オキシド、フェニルホスホン酸、トリス（β－クロロエチル）ホスフェート、トリス（ジクロロプロピル）ホスフェート、トリス（トリブロモネオペンチル）ホスフェート等が挙げられる。 Specific examples include triphenyl phosphate, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, phenylphosphonic acid, tris (β-chloroethyl) phosphate, tris (dichloropropyl) Examples thereof include phosphate and tris (tribromoneopentyl) phosphate.
　〈アクリル樹脂含有フィルムの製膜〉
　アクリル樹脂含有フィルムの製膜方法の例を説明するが、本発明はこれに限定されるものではない。 <Formation of acrylic resin-containing film>
Although the example of the film forming method of an acrylic resin containing film is demonstrated, this invention is not limited to this.
　本発明に係るアクリル樹脂含有フィルムの製膜方法としては、インフレーション法、Ｔ－ダイ法、カレンダー法、切削法、流延法、エマルジョン法、ホットプレス法等の製造法が使用できるが、着色抑制、異物欠点の抑制、ダイラインなどの光学欠点の抑制などの観点から流延法による溶液製膜が好ましい。セルロース樹脂をアクリル樹脂にブレンドして用いることは、フィルムを製造する工程が溶液流延であるとき、溶媒の乾燥性を向上させる観点で好ましい。またできあがったフィルムは、適度な透湿度をもつために本発明の目的が効果的に発現できる。 As a method for producing an acrylic resin-containing film according to the present invention, production methods such as an inflation method, a T-die method, a calendar method, a cutting method, a casting method, an emulsion method, and a hot press method can be used. From the viewpoints of suppressing foreign matter defects and optical defects such as die lines, solution casting by casting is preferred. Using a cellulose resin blended with an acrylic resin is preferable from the viewpoint of improving the drying property of the solvent when the step of producing a film is solution casting. Further, since the completed film has an appropriate moisture permeability, the object of the present invention can be effectively expressed.
　（有機溶媒）
　本発明に係るアクリル樹脂含有フィルムを溶液流延法で製造する場合のドープを形成するのに有用な有機溶媒は、アクリル樹脂、セルロースエステル樹脂、その他の添加剤を同時に溶解するものであれば制限なく用いることができる。 (Organic solvent)
The organic solvent useful for forming the dope when the acrylic resin-containing film according to the present invention is produced by the solution casting method is limited as long as it dissolves acrylic resin, cellulose ester resin, and other additives simultaneously. Can be used.
　例えば、塩素系有機溶媒としては、塩化メチレン、非塩素系有機溶媒としては、酢酸メチル、酢酸エチル、酢酸アミル、アセトン、テトラヒドロフラン、１，３－ジオキソラン、１，４－ジオキサン、シクロヘキサノン、ギ酸エチル、２，２，２－トリフルオロエタノール、２，２，３，３－ヘキサフルオロ－１－プロパノール、１，３－ジフルオロ－２－プロパノール、１，１，１，３，３，３－ヘキサフルオロ－２－メチル－２－プロパノール、１，１，１，３，３，３－ヘキサフルオロ－２－プロパノール、２，２，３，３，３－ペンタフルオロ－１－プロパノール、ニトロエタン等を挙げることができ、塩化メチレン、酢酸メチル、酢酸エチル、アセトンを好ましく使用し得る。 For example, as a chlorinated organic solvent, methylene chloride, as a non-chlorinated organic solvent, methyl acetate, ethyl acetate, amyl acetate, acetone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3-hexafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro- 2-methyl-2-propanol, 1,1,1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, etc. Methylene chloride, methyl acetate, ethyl acetate and acetone can be preferably used.
　ドープには、上記有機溶媒の他に、１～４０質量％の炭素原子数１～４の直鎖又は分岐鎖状の脂肪族アルコールを含有させることが好ましい。 In addition to the organic solvent, the dope preferably contains 1 to 40% by mass of a linear or branched aliphatic alcohol having 1 to 4 carbon atoms.
　ドープ中のアルコールの比率が高くなるとウェブがゲル化し、金属支持体からの剥離が容易になり、また、アルコールの割合が少ない時は非塩素系有機溶媒系でのアクリル樹脂、セルロースエステル樹脂の溶解を促進する役割もある。 When the proportion of alcohol in the dope increases, the web gels and peeling from the metal support becomes easy, and when the proportion of alcohol is small, the acrylic resin and cellulose ester resin dissolve in a non-chlorine organic solvent system. There is also a role to promote.
　特に、メチレンクロライド、及び炭素数１～４の直鎖又は分岐鎖状の脂肪族アルコールを含有する溶媒に、アクリル樹脂と、セルロースエステル樹脂と、アクリル粒子の３種を、少なくとも計１５～４５質量％溶解させたドープ組成物であることが好ましい。 In particular, in a solvent containing methylene chloride and a linear or branched aliphatic alcohol having 1 to 4 carbon atoms, at least 15 to 45 mass in total of at least three kinds of acrylic resin, cellulose ester resin, and acrylic particles. It is preferable that the dope composition is dissolved in%.
　炭素原子数１～４の直鎖又は分岐鎖状の脂肪族アルコールとしては、メタノール、エタノール、ｎ－プロパノール、ｉｓｏ－プロパノール、ｎ－ブタノール、ｓｅｃ－ブタノール、ｔｅｒｔ－ブタノールを挙げることができる。これらの内ドープの安定性、沸点も比較的低く、乾燥性もよいこと等からエタノールが好ましい。 Examples of the linear or branched aliphatic alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol, iso-propanol, n-butanol, sec-butanol, and tert-butanol. Ethanol is preferred because of the stability of these dopes, the relatively low boiling point, and good drying properties.
　以下、本発明に係るアクリル樹脂含有フィルムの好ましい製膜方法について説明する。 Hereinafter, a preferable method for forming an acrylic resin-containing film according to the present invention will be described.
　１）溶解工程
　アクリル樹脂、セルロースエステル樹脂に対する良溶媒を主とする有機溶に、溶解釜中で該アクリル樹脂、セルロースエステル樹脂、場合によってアクリル粒子、その他の添加剤を攪拌しながら溶解しドープを形成する工程、或いは該アクリル樹脂、セルロースエステル樹脂溶液に、場合によってアクリル粒子溶液、その他の添加剤溶液を混合して主溶解液であるドープを形成する工程である。 1) Dissolution process In an organic solution mainly composed of a good solvent for acrylic resin and cellulose ester resin, the acrylic resin, cellulose ester resin, and in some cases acrylic particles, and other additives are dissolved in a dissolution vessel while stirring. The step of forming, or the step of forming a dope which is a main solution by mixing the acrylic resin or cellulose ester resin solution with an acrylic particle solution or other additive solution as the case may be.
　アクリル樹脂、セルロースエステル樹脂の溶解には、常圧で行う方法、主溶媒の沸点以下で行う方法、主溶媒の沸点以上で加圧して行う方法、特開平９－９５５４４号公報、特開平９－９５５５７号公報、又は特開平９－９５５３８号公報に記載の如き冷却溶解法で行う方法、特開平１１－２１３７９号公報に記載の如き高圧で行う方法等種々の溶解方法を用いることができるが、特に主溶媒の沸点以上で加圧して行う方法が好ましい。 For dissolution of acrylic resin and cellulose ester resin, a method carried out at normal pressure, a method carried out below the boiling point of the main solvent, a method carried out under pressure above the boiling point of the main solvent, JP-A-9-95544 and JP-A-9- Various dissolution methods can be used such as a method performed by a cooling dissolution method as described in JP-A-95557 or JP-A-9-95538, a method performed at high pressure as described in JP-A No. 11-21379, In particular, a method of pressurizing at a temperature equal to or higher than the boiling point of the main solvent is preferable.
　ドープ中のアクリル樹脂と、セルロースエステル樹脂は、計１５～４５質量％の範囲であることが好ましい。溶解中又は後のドープに添加剤を加えて溶解及び分散した後、濾材で濾過し、脱泡して送液ポンプで次工程に送る。 The total amount of acrylic resin and cellulose ester resin in the dope is preferably 15 to 45% by mass. An additive is added to the dope during or after dissolution to dissolve and disperse, then filtered through a filter medium, defoamed, and sent to the next step with a liquid feed pump.
　濾過は捕集粒子径０．５～５μｍでかつ濾水時間１０～２５ｓｅｃ／１００ｍｌの濾材を用いることが好ましい。 For the filtration, it is preferable to use a filter medium having a collected particle diameter of 0.5 to 5 μm and a drainage time of 10 to 25 sec / 100 ml.
　この方法では、粒子分散時に残存する凝集物や主ドープ添加時発生する凝集物を、捕集粒子径０．５～５μｍでかつ濾水時間１０～２５ｓｅｃ／１００ｍｌの濾材を用いることで凝集物だけ除去できる。 In this method, agglomerates remaining at the time of particle dispersion and agglomerates generated upon addition of the main dope are only aggregated by using a filter medium having a collected particle diameter of 0.5 to 5 μm and a drainage time of 10 to 25 sec / 100 ml. Can be removed.
　主ドープでは粒子の濃度も添加液に比べ十分に薄いため、濾過時に凝集物同士がくっついて急激な濾圧上昇することもない。 In the main dope, the concentration of particles is sufficiently thinner than that of the additive solution, so that the aggregates do not stick together during filtration and the filtration pressure does not increase suddenly.
　図１は本発明に好ましい溶液流延製膜方法のドープ調製工程、流延工程及び乾燥工程を模式的に示した図である。 FIG. 1 is a diagram schematically showing a dope preparation step, a casting step, and a drying step of a solution casting film forming method preferable for the present invention.
　必要な場合は、アクリル粒子仕込釜４１より濾過器４４で大きな凝集物を除去し、ストック釜４２へ送液する。その後、ストック釜４２より主ドープ溶解釜１へアクリル粒子添加液を添加する。 If necessary, large aggregates are removed with a filter 44 from the acrylic particle charging vessel 41 and fed to the stock vessel 42. Thereafter, the acrylic particle additive solution is added from the stock kettle 42 to the main dope dissolving kettle 1.
　その後主ドープ液は主濾過器３にて濾過され、これに紫外線吸収剤添加液が１６よりインライン添加される。 Thereafter, the main dope solution is filtered by the main filter 3, and an ultraviolet absorbent additive solution is added in-line from 16 to this.
　多くの場合、主ドープには返材が１０～５０質量％程度含まれることがある。返材にはアクリル粒子が含まれることがある、その場合には返材の添加量に合わせてアクリル粒子添加液の添加量をコントロールすることが好ましい。 In many cases, the main dope may contain about 10 to 50% by weight of recycled material. The return material may contain acrylic particles. In that case, it is preferable to control the addition amount of the acrylic particle addition liquid in accordance with the addition amount of the return material.
　アクリル粒子を含有する添加液には、アクリル粒子を０．５～１０質量％含有していることが好ましく、１～１０質量％含有していることが更に好ましく、１～５質量％含有していることが最も好ましい。 The additive solution containing acrylic particles preferably contains 0.5 to 10% by mass of acrylic particles, more preferably 1 to 10% by mass, and more preferably 1 to 5% by mass. Most preferably.
　アクリル粒子の含有量の少ない方が、低粘度で取り扱い易く、アクリル粒子の含有量の多い方が、添加量が少なく、主ドープへの添加が容易になるため、上記の範囲が好ましい。 The lower the acrylic particle content, the easier it is to handle with a low viscosity, and the higher the acrylic particle content, the smaller the addition amount and the easier the addition to the main dope.
　返材とは、アクリル樹脂含有フィルムを細かく粉砕した物で、アクリル樹脂含有フィルムを製膜するときに発生する、フィルムの両サイド部分を切り落とした物や、擦り傷などでスペックアウトしたアクリル樹脂含有フィルム原反が使用される。 Recycled material is a finely pulverized acrylic resin-containing film that is generated when an acrylic resin-containing film is formed. The original fabric is used.
　また、予めアクリル樹脂、セルロースエステル樹脂、場合によってアクリル粒子を混練してペレット化したものも、好ましく用いることができる。 Also, an acrylic resin, a cellulose ester resin, and in some cases, acrylic particles kneaded into pellets can be preferably used.
　２）流延工程
　ドープを送液ポンプ（例えば、加圧型定量ギヤポンプ）を通して加圧ダイ３０に送液し、無限に移送する無端の金属ベルト３１、例えばステンレスベルト、或いは回転する金属ドラム等の金属支持体上の流延位置に、加圧ダイスリットからドープを流延する工程である。 2) Casting process An endless metal belt 31, such as a stainless steel belt or a rotating metal drum, which feeds the dope through a liquid feed pump (for example, a pressurized metering gear pump) to the pressure die 30 and transfers it infinitely. This is a step of casting the dope from the pressure die slit to the casting position on the support.
　ダイの口金部分のスリット形状を調整でき、膜厚を均一にし易い加圧ダイが好ましい。加圧ダイには、コートハンガーダイやＴダイ等があり、何れも好ましく用いられる。金属支持体の表面は鏡面となっている。製膜速度を上げるために加圧ダイを金属支持体上に２基以上設け、ドープ量を分割して重層してもよい。或いは複数のドープを同時に流延する共流延法によって積層構造のフィルムを得ることも好ましい。 ¡Pressure dies that can adjust the slit shape of the die base and make the film thickness uniform are preferred. The pressure die includes a coat hanger die and a T die, and any of them is preferably used. The surface of the metal support is a mirror surface. In order to increase the film forming speed, two or more pressure dies may be provided on the metal support, and the dope amount may be divided and stacked. Or it is also preferable to obtain the film of a laminated structure by the co-casting method which casts several dope simultaneously.
　３）溶媒蒸発工程
　ウェブ（流延用支持体上にドープを流延し、形成されたドープ膜をウェブと呼ぶ）を流延用支持体上で加熱し、溶媒を蒸発させる工程である。 3) Solvent evaporation step In this step, the web (the dope is cast on the casting support and the formed dope film is called a web) is heated on the casting support to evaporate the solvent.
　溶媒を蒸発させるには、ウェブ側から風を吹かせる方法及び／又は支持体の裏面から液体により伝熱させる方法、輻射熱により表裏から伝熱する方法等があるが、裏面液体伝熱方法が乾燥効率が良く好ましい。 To evaporate the solvent, there are a method of blowing air from the web side and / or a method of transferring heat from the back side of the support by a liquid, a method of transferring heat from the front and back by radiant heat, and the like. High efficiency and preferable.
　また、それらを組み合わせる方法も好ましく用いられる。流延後の支持体上のウェブを４０～１００℃の雰囲気下、支持体上で乾燥させることが好ましい。 Also, a method of combining them is preferably used. The web on the support after casting is preferably dried on the support in an atmosphere of 40 to 100 ° C.
　４０～１００℃の雰囲気下に維持するには、この温度の温風をウェブ上面に当てるか赤外線等の手段により加熱することが好ましい。 In order to maintain the atmosphere at 40 to 100 ° C., it is preferable to apply hot air at this temperature to the upper surface of the web or heat by means of infrared rays or the like.
　面品質、透湿性、剥離性の観点から、３０～１２０秒以内で該ウェブを支持体から剥離することが好ましい。 From the viewpoint of surface quality, moisture permeability, and peelability, it is preferable to peel the web from the support within 30 to 120 seconds.
　４）剥離工程
　金属支持体上で溶媒が蒸発したウェブを、剥離位置で剥離する工程である。剥離されたウェブは次工程に送られる。 4) Peeling process It is the process of peeling the web which the solvent evaporated on the metal support body in a peeling position. The peeled web is sent to the next process.
　金属支持体上の剥離位置における温度は好ましくは１０～４０℃であり、更に好ましくは１１～３０℃である。 The temperature at the peeling position on the metal support is preferably 10 to 40 ° C., more preferably 11 to 30 ° C.
　尚、剥離する時点での金属支持体上でのウェブの剥離時残留溶媒量は、乾燥の条件の強弱、金属支持体の長さ等により５０～１２０質量％の範囲で剥離することが好ましいが、残留溶媒量がより多い時点で剥離する場合、ウェブが柔らか過ぎると剥離時平面性を損なったり、剥離張力によるツレや縦スジが発生し易いため、経済速度と品質との兼ね合いで剥離時の残留溶媒量が決められる。 The residual solvent amount at the time of peeling of the web on the metal support at the time of peeling is preferably peeled in the range of 50 to 120% by mass depending on the strength of drying conditions, the length of the metal support, and the like. When peeling off at a time when the amount of residual solvent is larger, if the web is too soft, the flatness at the time of peeling will be impaired, and slippage and vertical stripes are likely to occur due to peeling tension, so the balance between economic speed and quality The amount of residual solvent is determined.
　ウェブの残留溶媒量は下記式で定義される。 The amount of residual solvent in the web is defined by the following formula.
　残留溶媒量（％）＝（ウェブの加熱処理前質量－ウェブの加熱処理後質量）／（ウェブの加熱処理後質量）×１００
　尚、残留溶媒量を測定する際の加熱処理とは、１１５℃で１時間の加熱処理を行うことを表す。 Residual solvent amount (%) = (mass before web heat treatment−mass after web heat treatment) / (mass after web heat treatment) × 100
Note that the heat treatment for measuring the residual solvent amount represents performing heat treatment at 115 ° C. for 1 hour.
　金属支持体とフィルムを剥離する際の剥離張力は、通常、１９６～２４５Ｎ／ｍであるが、剥離の際に皺が入り易い場合、１９０Ｎ／ｍ以下の張力で剥離することが好ましく、更には、剥離できる最低張力～１６６．６Ｎ／ｍ、次いで、最低張力～１３７．２Ｎ／ｍで剥離することが好ましいが、特に好ましくは最低張力～１００Ｎ／ｍで剥離することである。 The peeling tension at the time of peeling the metal support from the film is usually 196 to 245 N / m. However, if wrinkles easily occur at the time of peeling, it is preferable to peel with a tension of 190 N / m or less. It is preferable to peel at a minimum tension of ˜166.6 N / m, and then peel at a minimum tension of ˜137.2 N / m, and particularly preferable to peel at a minimum tension of ˜100 N / m.
　本発明においては、該金属支持体上の剥離位置における温度を－５０～４０℃とするのが好ましく、１０～４０℃がより好ましく、１５～３０℃とするのが最も好ましい。 In the present invention, the temperature at the peeling position on the metal support is preferably −50 to 40 ° C., more preferably 10 to 40 ° C., and most preferably 15 to 30 ° C.
　５）乾燥及び延伸工程
　剥離後、ウェブを乾燥装置内に複数配置したロールに交互に通して搬送する乾燥装置３５、及び／又はクリップでウェブの両端をクリップして搬送するテンター延伸装置３４を用いて、ウェブを乾燥する。 5) Drying and stretching step After peeling, a drying device 35 that transports the web alternately through rolls arranged in the drying device and / or a tenter stretching device 34 that clips and transports both ends of the web with clips. And dry the web.
　乾燥手段はウェブの両面に熱風を吹かせるのが一般的であるが、風の代わりにマイクロウェーブを当てて加熱する手段もある。余り急激な乾燥はでき上がりのフィルムの平面性を損ね易い。高温による乾燥は残留溶媒が８質量％以下くらいから行うのがよい。全体を通し、乾燥は概ね４０～２５０℃で行われる。特に４０～１６０℃で乾燥させることが好ましい。 The drying means is generally to blow hot air on both sides of the web, but there is also a means to heat by applying microwaves instead of wind. Too rapid drying tends to impair the flatness of the finished film. Drying at a high temperature is preferably performed from about 8% by mass or less of residual solvent. Throughout, drying is generally performed at 40-250 ° C. In particular, drying at 40 to 160 ° C. is preferable.
　テンター延伸装置を用いる場合は、テンターの左右把持手段によってフィルムの把持長（把持開始から把持終了までの距離）を左右で独立に制御できる装置を用いることが好ましい。また、テンター工程において、平面性を改善するため意図的に異なる温度を持つ区画を作ることも好ましい。 When using a tenter stretching apparatus, it is preferable to use an apparatus that can independently control the film gripping length (distance from the start of gripping to the end of gripping) left and right by the left and right gripping means of the tenter. In the tenter process, it is also preferable to intentionally create sections having different temperatures in order to improve planarity.
　また、異なる温度区画の間にそれぞれの区画が干渉を起こさないように、ニュートラルゾーンを設けることも好ましい。 It is also preferable to provide a neutral zone between different temperature zones so that each zone does not cause interference.
　尚、延伸操作は多段階に分割して実施してもよく、流延方向、幅手方向に二軸延伸を実施することも好ましい。また、二軸延伸を行う場合には同時二軸延伸を行ってもよいし、段階的に実施してもよい。 The stretching operation may be performed in multiple stages, and it is also preferable to perform biaxial stretching in the casting direction and the width direction. When biaxial stretching is performed, simultaneous biaxial stretching may be performed or may be performed stepwise.
　この場合、段階的とは、例えば、延伸方向の異なる延伸を順次行うことも可能であるし、同一方向の延伸を多段階に分割し、かつ異なる方向の延伸をそのいずれかの段階に加えることも可能である。即ち、例えば、次のような延伸ステップも可能である。 In this case, stepwise means that, for example, stretching in different stretching directions can be sequentially performed, stretching in the same direction is divided into multiple stages, and stretching in different directions is added to any one of the stages. Is also possible. That is, for example, the following stretching steps are possible.
　・流延方向に延伸－幅手方向に延伸－流延方向に延伸－流延方向に延伸
　・幅手方向に延伸－幅手方向に延伸－流延方向に延伸－流延方向に延伸
　また、同時２軸延伸には、一方向に延伸し、もう一方を張力を緩和して収縮させる場合も含まれる。同時２軸延伸の好ましい延伸倍率は幅手方向、長手方向ともに×１．０１倍～×１．５倍の範囲でとることができる。 -Stretch in the casting direction-Stretch in the width direction-Stretch in the casting direction-Stretch in the casting direction-Stretch in the width direction-Stretch in the width direction-Stretch in the casting direction-Stretch in the casting direction Simultaneous biaxial stretching includes stretching in one direction and contracting the other while relaxing the tension. The preferred draw ratio for simultaneous biaxial stretching can be in the range of x1.01 to x1.5 in both the width direction and the longitudinal direction.
　テンターを行う場合のウェブの残留溶媒量は、テンター開始時に２０～１００質量％であるのが好ましく、かつウェブの残留溶媒量が１０質量％以下になる迄テンターを掛けながら乾燥を行うことが好ましく、更に好ましくは５質量％以下である。 When the tenter is used, the amount of residual solvent in the web is preferably 20 to 100% by mass at the start of the tenter, and drying is preferably performed while the tenter is applied until the amount of residual solvent in the web is 10% by mass or less. More preferably, it is 5% by mass or less.
　テンターを行う場合の乾燥温度は、３０～１５０℃が好ましく、５０～１２０℃が更に好ましく、７０～１００℃が最も好ましい。 When performing the tenter, the drying temperature is preferably 30 to 150 ° C, more preferably 50 to 120 ° C, and most preferably 70 to 100 ° C.
　テンター工程において、雰囲気の幅手方向の温度分布が少ないことが、フィルムの均一性を高める観点から好ましく、テンター工程での幅手方向の温度分布は、±５℃以内が好ましく、±２℃以内がより好ましく、±１℃以内が最も好ましい。 In the tenter process, it is preferable that the temperature distribution in the width direction of the atmosphere is small from the viewpoint of improving the uniformity of the film. The temperature distribution in the width direction in the tenter process is preferably within ± 5 ° C, and within ± 2 ° C. Is more preferable, and within ± 1 ° C. is most preferable.
　６）巻き取り工程
　ウェブ中の残留溶媒量が２質量％以下となってからアクリル樹脂含有フィルムとして巻き取り機３７により巻き取る工程であり、残留溶媒量を０．４質量％以下にすることにより寸法安定性の良好なフィルムを得ることができる。 6) Winding step This is a step of winding up the acrylic resin-containing film by the winder 37 after the residual solvent amount in the web is 2% by mass or less, and by setting the residual solvent amount to 0.4% by mass or less. A film having good dimensional stability can be obtained.
　巻き取り方法は、一般に使用されているものを用いればよく、定トルク法、定テンション法、テーパーテンション法、内部応力一定のプログラムテンションコントロール法等があり、それらを使いわければよい。 As a winding method, a generally used one may be used, and there are a constant torque method, a constant tension method, a taper tension method, a program tension control method with a constant internal stress, etc., and these may be used properly.
　本発明に係るアクリル樹脂含有フィルムは、長尺フィルムであることが好ましく、具体的には、１００ｍ～５０００ｍ程度のものを示し、通常、ロール状で提供される形態のものである。また、フィルムの幅は１．３～４ｍであることが好ましく、１．４～２ｍであることがより好ましい。 The acrylic resin-containing film according to the present invention is preferably a long film. Specifically, the acrylic resin-containing film has a thickness of about 100 m to 5000 m and is usually provided in a roll shape. The film width is preferably 1.3 to 4 m, more preferably 1.4 to 2 m.
　本発明においては、長尺フィルムの製造時にフィルムの面が平滑になる観点でテンターを活用した延伸が好ましく、幅方向の延伸倍率が製膜方向の延伸倍率よりも大きくすることで延伸ムラのないフィルムが得られる点で優れている。 In the present invention, stretching using a tenter is preferable from the viewpoint of smoothing the surface of the film during the production of a long film, and there is no unevenness of stretching by making the stretching ratio in the width direction larger than the stretching ratio in the film forming direction. It is excellent in that a film can be obtained.
　この製造工程で得た長尺フィルムの面内屈折率は、幅方向が最小となり、進相軸は幅方向に一致し遅相軸は製膜方向に一致する。 The in-plane refractive index of the long film obtained in this production process is minimized in the width direction, the fast axis coincides with the width direction, and the slow axis coincides with the film forming direction.
　〈接着性付与層、接着層〉
　本発明においては、本発明の偏光板及び液晶表示装置の各構成要素を各々貼合するため、必要に応じて、接着性付与層を設けることを要する。 <Adhesive layer, adhesive layer>
In this invention, in order to paste each component of the polarizing plate of this invention, and a liquid crystal display device, it is required to provide an adhesive provision layer as needed.
　なお、本発明の偏光板は、当該接着層を第２光学異方性層と第１光学異方性層の間に設けることを特徴とする。ここで、「接着層」とは、接着性付与層のうち、特に第２光学異方性層と第１光学異方性層を各々貼合するための接着性付与層をいう。 The polarizing plate of the present invention is characterized in that the adhesive layer is provided between the second optical anisotropic layer and the first optical anisotropic layer. Here, the “adhesion layer” refers to an adhesion imparting layer for bonding the second optical anisotropic layer and the first optical anisotropic layer, respectively, among the adhesion imparting layers.
　本発明における接着性付与層として用いる材料は、セルローストリアセテート、セルロースジアセテート、セルロースアセテートプロピオネート、セルロースアセテートブチレートなどのセルロースエステル、親水性セルロース誘導体（例えば、メチルセルロース、カルボキシメチルセルロース、ヒドロキシセルロース等）、ポリビニルアルコール誘導体（例えば、ポリビニルアルコール、酢酸ビニル－ビニルアルコール共重合体、ポリビニルアセタール、ポリビニルホルマール、ポリビニルベンザール等）、天然高分子化合物（例えば、ゼラチン、カゼイン、アラビアゴム等）、親水性ポリエステル誘導体（例えば、部分的にスルホン化されたポリエチレンテレフタレート等）、親水性ポリビニル誘導体（例えば、ポリ－Ｎ－ビニルピロリドン、ポリアクリルアミド、ポリビニルインダゾール、ポリビニルピラゾール等）が挙げられ、中でも、セルロースジアセテートが好ましく用いられる。 Materials used as the adhesion-imparting layer in the present invention are cellulose esters such as cellulose triacetate, cellulose diacetate, cellulose acetate propionate, and cellulose acetate butyrate, and hydrophilic cellulose derivatives (for example, methylcellulose, carboxymethylcellulose, hydroxycellulose, etc.) , Polyvinyl alcohol derivatives (eg, polyvinyl alcohol, vinyl acetate-vinyl alcohol copolymer, polyvinyl acetal, polyvinyl formal, polyvinyl benzal, etc.), natural polymer compounds (eg, gelatin, casein, gum arabic, etc.), hydrophilic polyester Derivatives (eg, partially sulfonated polyethylene terephthalate), hydrophilic polyvinyl derivatives (eg, poly-N-vinylpyrrole) Pyrrolidone, polyacrylamide, polyvinyl indazole, polyvinyl pyrazole, etc.). Among them, a cellulose diacetate is preferably used.
　本発明において、接着性付与層の塗設に用いる溶媒としては、溶解させる溶媒もしくは膨潤させる溶媒の混合比率を大きくし、溶解させない溶媒の比率を小さくするのが効果的である。この混合比率は好ましくは（溶解させる溶媒もしくは膨潤させる溶媒）：（溶解させない溶媒）＝１０：０～１：９で用いられる。このような混合組成物に含まれる、偏光板用保護フィルムを溶解又は膨潤させる溶媒としては、例えば、ジオキサン、アセトン、メチルエチルケトン、Ｎ，Ｎ－ジメチルホルムアミド、酢酸メチル、酢酸エチル、トリクロロエチレン、メチレンクロライド、エチレンクロライド、テトラクロロエタン、トリクロロエタン、クロロホルムなどがある。溶解させない溶媒としては、例えば、メタノール、エタノール、ｎ－プロピルアルコール、ｉ－プロピルアルコール、ｎ－ブタノール或いは炭化水素類（トルエン、キシレン、シクロヘキサノール）などがある。 In the present invention, as the solvent used for coating the adhesion-imparting layer, it is effective to increase the mixing ratio of the solvent to be dissolved or the solvent to be swollen and to decrease the ratio of the solvent that is not dissolved. This mixing ratio is preferably (solvent to be dissolved or solvent to be swollen) :( solvent not to be dissolved) = 10: 0 to 1: 9. Examples of the solvent for dissolving or swelling the protective film for polarizing plate contained in such a mixed composition include dioxane, acetone, methyl ethyl ketone, N, N-dimethylformamide, methyl acetate, ethyl acetate, trichloroethylene, methylene chloride, Examples include ethylene chloride, tetrachloroethane, trichloroethane, and chloroform. Examples of the solvent that does not dissolve include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butanol, and hydrocarbons (toluene, xylene, cyclohexanol).
　これらの塗布組成物をグラビアコーター、ディップコーター、リバースコーター、ワイヤーバーコーター、ダイコーター等を用いて偏光板用保護フィルムの表面に乾燥後の膜厚が０．１～２μｍになるように塗布するのが好ましいく、特に膜厚が０．１～１．０μｍであることが好ましい。偏光板に加工する際、フィルムの表面の濡れ性を改良する目的でアルカリ水溶液で処理する場合、接着性付与層がアルカリ水溶液中に流出することがある。これらの抑制するために接着性付与層に架橋剤を用いてもよく、イソシアネート系架橋剤が好ましく用いられる。本発明に用いるフィルム自身をアルカリ水溶液を用いて加水分解する場合は、フィルムの表面が加水分解されるので、これを接着性付与層とすることができる。偏光子と偏光板保護フィルムの接着においては、接着性付与層が該フィルムの表面に存在することが重要である。 These coating compositions are applied to the surface of the protective film for a polarizing plate using a gravure coater, dip coater, reverse coater, wire bar coater, die coater or the like so that the film thickness after drying is 0.1 to 2 μm. In particular, the film thickness is preferably 0.1 to 1.0 μm. When processing into a polarizing plate, when processing with the aqueous alkali solution for the purpose of improving the wettability of the film surface, the adhesion-imparting layer may flow out into the aqueous alkaline solution. In order to suppress these, a crosslinking agent may be used in the adhesion-imparting layer, and an isocyanate-based crosslinking agent is preferably used. When the film itself used in the present invention is hydrolyzed using an alkaline aqueous solution, the surface of the film is hydrolyzed, and this can be used as an adhesion-imparting layer. In the adhesion between the polarizer and the polarizing plate protective film, it is important that the adhesion providing layer is present on the surface of the film.
　また、上記塗布液を乾燥させる温度としては、８０～１２０℃が好ましく、１００～１１０℃であることがより好ましい。 The temperature for drying the coating solution is preferably 80 to 120 ° C., more preferably 100 to 110 ° C.
　本発明において、偏光子と偏光板保護フィルム、偏光子と第２光学異方性層、第２光学異方性層と第１光学異方性層を各々貼合するためには接着剤を用いる。接着剤を塗設した層の２５℃での貯蔵弾性率は１．０×１０４Ｐａ～１．０×１０９Ｐａの範囲であることが好ましく、接着剤を偏光子と偏光板保護フィルム、偏光子と第２光学異方性層、第２光学異方性層と第１光学異方性層の各々の接着面の少なくともいずれかに接着剤を含む塗布液を塗布して接着により貼合することができる。接着剤の塗布液を均一に塗設するために、上述のように、偏光板保護フィルム、第２光学異方性層であるフィルム、第１光学異方性層の少なくともいずれかの面に、接着性付与層を設置、又は処理を行うことが好ましい。また、コロナ処理を行って、接着剤の含む塗布液を均一に塗設することができる。 In the present invention, an adhesive is used to bond the polarizer and the polarizing plate protective film, the polarizer and the second optical anisotropic layer, and the second optical anisotropic layer and the first optical anisotropic layer, respectively. . The storage elastic modulus at 25 ° C. of the layer coated with the adhesive is preferably in the range of 1.0 × 10 4 Pa to 1.0 × 10 9 Pa. The adhesive is a polarizer and a polarizing plate protective film, A coating solution containing an adhesive is applied to at least one of the bonding surfaces of the polarizer and the second optical anisotropic layer, and the second optical anisotropic layer and the first optical anisotropic layer, and bonded by adhesion. can do. In order to uniformly apply the adhesive coating solution, as described above, the polarizing plate protective film, the film that is the second optical anisotropic layer, and at least one surface of the first optical anisotropic layer, It is preferable to install or treat an adhesion-imparting layer. Moreover, it can corona-treat and can apply | coat the coating liquid containing an adhesive agent uniformly.
　偏光板の製造工程で、接着剤を塗設するときに用いた溶媒が水の場合、偏光子の偏光ムラを発生させない観点から、乾燥温度は７０℃以下であることが好ましく、６５℃以下であることが好ましい。一方乾燥温度が低いと、乾燥速度が遅くなり、低い生産性の要因となってしまうことがある。従って乾燥温度は、３０℃以上が好ましく、３５℃以上、より好ましくは４０℃以上であることが好ましい。 In the production process of the polarizing plate, when the solvent used when applying the adhesive is water, the drying temperature is preferably 70 ° C. or less, and 65 ° C. or less from the viewpoint of not causing uneven polarization of the polarizer. Preferably there is. On the other hand, when the drying temperature is low, the drying speed is slow, which may cause low productivity. Therefore, the drying temperature is preferably 30 ° C. or higher, preferably 35 ° C. or higher, more preferably 40 ° C. or higher.
　また接着剤は、貼り合わせた後に種々の化学反応により高分子量体又は架橋構造を形成する硬化型粘着剤も用いてもよい。 Further, as the adhesive, a curable pressure-sensitive adhesive that forms a high molecular weight body or a crosslinked structure by various chemical reactions after being bonded may also be used.
　具体例としては、例えば、ウレタン系接着剤、エポキシ系接着剤、水性高分子－イソシアネート系接着剤、熱硬化型アクリル接着剤等の硬化型接着剤、湿気硬化ウレタン接着剤、ポリエーテルメタクリレート型、エステル系メタクリレート型、酸化型ポリエーテルメタクリレート等の嫌気性接着剤、シアノアクリレート系の瞬間接着剤、アクリレートとペルオキシド系の２液型瞬間接着剤等が挙げられる。 Specific examples include, for example, urethane adhesives, epoxy adhesives, aqueous polymer-isocyanate adhesives, curable adhesives such as thermosetting acrylic adhesives, moisture curable urethane adhesives, polyether methacrylate types, Examples include anaerobic adhesives such as ester-based methacrylate type and oxidized polyether methacrylate, cyanoacrylate-based instant adhesives, acrylate-peroxide-based two-component instant adhesives, and the like.
　上記接着剤としては１液型であっても良いし、使用前に２液以上を混合して使用する型であっても良い。 The adhesive may be a one-component type, or a type in which two or more components are mixed before use.
　偏光子を含むフィルムの接着においては、高い偏光度を維持するために、接着剤溶液は水を主体とした溶媒であること、あるいは接着剤の分散液の溶媒が水を主体とすることが特に好ましい。 In the adhesion of a film containing a polarizer, in order to maintain a high degree of polarization, it is particularly preferable that the adhesive solution is a solvent mainly composed of water, or the solvent of the adhesive dispersion is mainly composed of water. preferable.
　溶媒が水を主成分とする接着剤は、エマルジョン型、コロイド分散液型、水溶液型などの水系であることが好ましい。 The adhesive whose solvent is mainly water is preferably an aqueous type such as an emulsion type, a colloidal dispersion type, or an aqueous solution type.
　ポリビニルアルコール誘導体の水溶液、あるいは、水分散性のウレタン系接着剤と架橋剤を併用して用いる接着剤であることが本発明においては特に好ましい。 In the present invention, an aqueous solution of a polyvinyl alcohol derivative or an adhesive using a water-dispersible urethane adhesive and a crosslinking agent in combination is particularly preferred.
　上記接着剤を含む液の濃度は、接着層の膜厚、塗布方法、塗布条件等により適宜決定されれば良く、通常は０．１～５０質量％である。接着層の膜厚は、５ｎｍ～１０μｍ、さらに１０ｎｍ～５μｍであることが好ましく、接着層からみて隣接するフィルムの界面と接着層との屈折率は同一、あるいは屈折率差が０．０１以下であることが、光透過の観点から好ましい。上記屈折率の差が大きく、かつ接着層の膜厚が大きいと反射により光の透過率は低下することになる。 The concentration of the liquid containing the adhesive may be appropriately determined depending on the film thickness of the adhesive layer, the application method, the application conditions, and the like, and is usually 0.1 to 50% by mass. The film thickness of the adhesive layer is preferably 5 nm to 10 μm, more preferably 10 nm to 5 μm, and the refractive index of the adhesive layer between the interface of the adjacent film as viewed from the adhesive layer is the same, or the refractive index difference is 0.01 or less. It is preferable from the viewpoint of light transmission. When the difference in refractive index is large and the film thickness of the adhesive layer is large, the light transmittance decreases due to reflection.
　〈粘着層〉
　本発明の偏光板は、液晶セルのガラス基板に粘着層を介して貼り付けることを特徴とする。 <Adhesive layer>
The polarizing plate of the present invention is characterized by being attached to a glass substrate of a liquid crystal cell via an adhesive layer.
　当該粘着層の厚さは、５μｍ～５０μｍ、さらに１０μｍ～３０μｍであることが好ましい。このとき粘着層は偏光板にあらかじめ設置しておいて、液晶セルに偏光板を貼合することができる。 The thickness of the adhesive layer is preferably 5 μm to 50 μm, more preferably 10 μm to 30 μm. At this time, the pressure-sensitive adhesive layer can be previously installed on the polarizing plate, and the polarizing plate can be bonded to the liquid crystal cell.
　該粘着層は、水分散型粘着剤を用いることが偏光度の保持の観点から好ましく、水分散性粘着剤を偏光板に塗設して乾燥によって偏光板上に粘着層を設置するか、他の剥離できるフィルムに粘着層を設置してから、本発明の偏光板に粘着層を転写してもよい。偏光板の製造工程において、粘着層に残存する若干の溶媒が存在するとき、有機溶媒よりも水であることが偏光子の偏光度を維持することができるためである。 The pressure-sensitive adhesive layer is preferably a water-dispersed pressure-sensitive adhesive from the viewpoint of maintaining the degree of polarization. A water-dispersible pressure-sensitive adhesive is coated on the polarizing plate, and the pressure-sensitive adhesive layer is placed on the polarizing plate by drying. After the adhesive layer is placed on the peelable film, the adhesive layer may be transferred to the polarizing plate of the present invention. This is because in the production process of the polarizing plate, when there is some solvent remaining in the pressure-sensitive adhesive layer, the degree of polarization of the polarizer can be maintained by using water rather than the organic solvent.
　水分散型粘着剤としては、ゴム系粘着剤、アクリル系粘着剤、シリコーン系粘着剤等の各種の水分散型粘着剤を使用できるが、無色透明で、液晶セル（ガラス基板）との接着性の良好なアクリル系粘着剤が好ましい。 Various water-dispersed pressure-sensitive adhesives such as rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, and silicone-based pressure-sensitive adhesives can be used as water-dispersible pressure-sensitive adhesives, but they are colorless and transparent, and have adhesion to liquid crystal cells (glass substrates). A preferable acrylic pressure-sensitive adhesive is preferable.
　＜偏光板＞
　本発明の偏光板は、少なくとも第１光学異方性層及び第２光学異方性層を有する偏光板であって、粘着層／第１光学異方性層／接着層／第２光学異方性層／偏光子の順で構成されることを特徴とする。 <Polarizing plate>
The polarizing plate of the present invention is a polarizing plate having at least a first optical anisotropic layer and a second optical anisotropic layer, and is an adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic. It is characterized by comprising in the order of a functional layer / a polarizer.
　偏光子には、ヨウ素系偏光子、二色性染料を用いる染料系偏光子やポリエン系偏光子を用いることができる。 As the polarizer, an iodine-based polarizer, a dye-based polarizer using a dichroic dye, or a polyene-based polarizer can be used.
　ヨウ素系偏光子及び染料系偏光子は、一般にポリビニルアルコール系フィルムを用いて製造する。偏光子の吸収軸は、フィルムの延伸方向に相当する。従って、縦方向（搬送方向）に延伸された偏光子は長手方向に対して平行に吸収軸を有し、横方向（搬送方向と垂直方向）に延伸された偏光子は長手方向に対して垂直に吸収軸を有す。 Iodine polarizer and dye polarizer are generally produced using a polyvinyl alcohol film. The absorption axis of the polarizer corresponds to the stretching direction of the film. Accordingly, a polarizer stretched in the longitudinal direction (transport direction) has an absorption axis parallel to the longitudinal direction, and a polarizer stretched in the lateral direction (perpendicular to the transport direction) is perpendicular to the longitudinal direction. Has an absorption axis.
　本発明の偏光板の好ましい製造方法は、偏光子と位相差フィルムとをそれぞれ長尺の状態で連続的に積層される工程を含む。該長尺の偏光板は用いられる液晶表示装置の画面の大きさに合わせて裁断される。 A preferred method for producing the polarizing plate of the present invention includes a step of successively laminating a polarizer and a retardation film in a long state. The long polarizing plate is cut according to the screen size of the liquid crystal display device used.
　偏光子は、一般に双方の表面に保護膜を有する。本発明に係る位相差フィルム中に含まれるセルロースエステルフィルムを、偏光子の保護膜として機能させることができ、かかる場合は、前記位相差フィルム側の偏光子の表面には別途保護膜を貼り合わせる必要はない。 A polarizer generally has a protective film on both surfaces. The cellulose ester film contained in the retardation film according to the present invention can function as a protective film for the polarizer. In such a case, a protective film is separately attached to the surface of the polarizer on the retardation film side. There is no need.
　本発明の偏光板において、観察側と光源側の各々の偏光子に挟まれた偏光板保護フィルムは本発明を構成するフィルム以外に光学的に等方的な接着層、及び／又は光学的に等方的な透明保護フィルムが含まれているのが好ましい。 In the polarizing plate of the present invention, the polarizing plate protective film sandwiched between the polarizers on the observation side and the light source side is an optically isotropic adhesive layer and / or optically other than the film constituting the present invention. It is preferable that an isotropic transparent protective film is included.
　光学的に等方的な透明保護フィルムとしては、具体的には、面内のリターデーションＲｏが－１０～０～１０ｎｍ、厚さ方向のリターデーションＲｔが－２０～２０ｎｍであるフィルムである。セルロースエステル又は環状ポリオレフィンを含むフィルム、あるいはアクリル樹脂を含むフィルムが好ましい。 The optically isotropic transparent protective film is specifically a film having an in-plane retardation Ro of -10 to 0 to 10 nm and a thickness direction retardation Rt of -20 to 20 nm. A film containing cellulose ester or cyclic polyolefin, or a film containing acrylic resin is preferred.
　本発明の偏光板は、前記第１光学異方性層、前記第２光学異方性層、及び前記偏光子が、この順で積層されており、且つ、前記第２光学異方性層の遅相軸の方向と前記偏光子の吸収軸の方向とが、実質的に直交している偏光板である。 In the polarizing plate of the present invention, the first optical anisotropic layer, the second optical anisotropic layer, and the polarizer are laminated in this order, and the second optical anisotropic layer of the second optical anisotropic layer In the polarizing plate, the direction of the slow axis and the direction of the absorption axis of the polarizer are substantially orthogonal.
　特定のセルロースエステルフィルムからなる第２光学異方性層の遅相軸の方向は、セルロースエステルフィルムを作製する際の延伸方向等によって調整することができる。 The direction of the slow axis of the second optically anisotropic layer made of a specific cellulose ester film can be adjusted by the stretching direction when the cellulose ester film is produced.
　本発明において、６０℃、９５％ＲＨにおける、第１光学異方性層を構成するフィルムの透湿度が２０～６００ｇ／ｍ２・２４ｈの範囲内であり、第２光学異方性層を構成するフィルムの透湿度が６００～１５００ｇ／ｍ２・２４ｈの関係であることは、以下の観点で優れている。 In the present invention, the moisture permeability of the film constituting the first optical anisotropic layer at 60 ° C. and 95% RH is in the range of 20 to 600 g / m 2 · 24 h, and constitutes the second optical anisotropic layer. It is excellent from the following viewpoint that the moisture permeability of the film is 600 to 1500 g / m 2 · 24 h.
　上記粘着層／第１光学異方性層／接着層／第２光学異方性層／偏光子の構成で本発明の偏光板を用いる。このとき、第１光学異方性層／接着層／第２光学異方性層／偏光子／セルロース系偏光板保護フィルムの構成をもつ偏光板は、第２光学異方性層／偏光子／セルロース系偏光板保護フィルムの構成で一次偏光板を作製し、その後、第１光学異方性層／接着層／第２光学異方性層／偏光子／セルロース系偏光板保護フィルムとなるように接着層を介して第１光学異方性層のフィルムが配置された偏光板を作製することが好ましい。 The polarizing plate of the present invention is used in the configuration of the pressure-sensitive adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic layer / polarizer. At this time, the polarizing plate having the configuration of the first optically anisotropic layer / adhesive layer / second optically anisotropic layer / polarizer / cellulose-based polarizing plate protective film is the second optically anisotropic layer / polarizer / A primary polarizing plate is prepared with the structure of a cellulose-based polarizing plate protective film, and then, the first optical anisotropic layer / adhesive layer / second optical anisotropic layer / polarizer / cellulose-based polarizing plate protective film is formed. It is preferable to produce a polarizing plate in which a film of the first optical anisotropic layer is disposed via an adhesive layer.
　第２光学異方性層／偏光子／セルロース系偏光板保護フィルムを製造するときに、第２光学異方性層の透湿度は、６０℃、９５％ＲＨにおいて、６００～１５００ｇ／ｍ２・２４ｈであることが、偏光板の製造工程の乾燥性の観点から必要である。 When the second optically anisotropic layer / polarizer / cellulose polarizing plate protective film is produced, the moisture permeability of the second optically anisotropic layer is 600 to 1500 g / m 2 · at 60 ° C. and 95% RH. It is necessary from a viewpoint of the drying property of the manufacturing process of a polarizing plate that it is 24h.
　接着層は、水や有機溶媒、あるいは水と有機溶媒を併用して接着剤を塗設することができ、このときに接着層塗設に用いた水あるいは有機溶媒を乾燥する必要がある。 The adhesive layer can be coated with an adhesive using water or an organic solvent, or a combination of water and an organic solvent. At this time, it is necessary to dry the water or the organic solvent used for coating the adhesive layer.
　＜液晶表示装置＞
　本発明の液晶表示装置は、本発明の偏光板を少なくとも含む。本発明の液晶表示装置は、反射型、半透過型、透過型液晶表示装置等のいずれであってもよい。 <Liquid crystal display device>
The liquid crystal display device of the present invention includes at least the polarizing plate of the present invention. The liquid crystal display device of the present invention may be any of a reflection type, a semi-transmission type, a transmission type liquid crystal display device and the like.
　液晶表示装置は、一般的に、偏光板、液晶セル、及び必要に応じて位相差板、反射層、光拡散層、バックライト、フロントライト、光制御フィルム、導光板、プリズムシート、カラーフィルター等の部材から構成されるが、本発明においては本発明の偏光板を使用することを必須とする点を除いて特に制限はない。 A liquid crystal display device generally includes a polarizing plate, a liquid crystal cell, and, if necessary, a retardation plate, a reflective layer, a light diffusion layer, a backlight, a front light, a light control film, a light guide plate, a prism sheet, a color filter, etc. In the present invention, there is no particular limitation except that it is essential to use the polarizing plate of the present invention.
　液晶セルとしては、特に制限されず、電極を備える一対の透明基板で液晶層を狭持したもの等の一般的な液晶セルが使用できる。液晶セルを構成する前記透明基板としては、液晶層を構成する液晶性を示す材料を特定の配向方向に配向させるものであれば特に制限はない。 The liquid crystal cell is not particularly limited, and a general liquid crystal cell such as a liquid crystal layer sandwiched between a pair of transparent substrates provided with electrodes can be used. The transparent substrate constituting the liquid crystal cell is not particularly limited as long as the liquid crystal material constituting the liquid crystal layer is aligned in a specific alignment direction.
　具体的には、基板自体が液晶を配向させる性質を有していている透明基板、基板自体は配向能に欠けるが、液晶を配向させる性質を有する配向膜等をこれに設けた透明基板等がいずれも使用できる。 Specifically, a transparent substrate in which the substrate itself has a property of orienting liquid crystals, a transparent substrate in which an alignment film having the property of orienting liquid crystals is provided, but the substrate itself lacks the alignment ability. Either can be used.
　また、液晶セルの電極は、公知のものが使用できる。通常、液晶層が接する透明基板の面上に設けることができ、配向膜を有する基板を使用する場合は、基板と配向膜との間に設けることができる。 Also, known electrodes can be used for the electrodes of the liquid crystal cell. Usually, it can be provided on the surface of the transparent substrate in contact with the liquid crystal layer, and when a substrate having an alignment film is used, it can be provided between the substrate and the alignment film.
　前記液晶層を形成する液晶性を示す材料としては、特に制限されず、各種の液晶セルを構成し得る通常の各種低分子液晶性化合物、高分子液晶性化合物及びこれらの混合物が挙げられる。また、これらに液晶性を損なわない範囲で色素やカイラル剤、非液晶性化合物等を添加することもできる。 The material exhibiting liquid crystallinity for forming the liquid crystal layer is not particularly limited, and examples thereof include various ordinary low-molecular liquid crystalline compounds, high-molecular liquid crystalline compounds, and mixtures thereof that can constitute various liquid crystal cells. Moreover, a pigment | dye, a chiral agent, a non-liquid crystalline compound, etc. can also be added to these in the range which does not impair liquid crystallinity.
　前記液晶セルは、前記電極基板及び液晶層の他に、後述する各種の方式の液晶セルとするのに必要な各種の構成要素を備えていてもよい。 In addition to the electrode substrate and the liquid crystal layer, the liquid crystal cell may include various components necessary for forming various types of liquid crystal cells described later.
　前記液晶セルの方式としては、ＴＮ（Ｔｗｉｓｔｅｄ　Ｎｅｍａｔｉｃ）方式、ＳＴＮ（Ｓｕｐｅｒ　Ｔｗｉｓｔｅｄ　Ｎｅｍａｔｉｃ）方式、ＥＣＢ（Ｅｌｅｃｔｒｉｃａｌｌｙ　Ｃｏｎｔｒｏｌｌｅｄ　Ｂｉｒｅｆｒｉｎｇｅｎｃｅ）方式、ＩＰＳ（Ｉｎ－Ｐｌａｎｅ　Ｓｗｉｔｃｈｉｎｇ）方式、ＶＡ（Ｖｅｒｔｉｃａｌ　Ａｌｉｇｎｍｅｎｔ）方式、ＭＶＡ（Ｍｕｌｔｉｄｏｍａｉｎ　Ｖｅｒｔｉｃａｌ　Ａｌｉｇｎｍｅｎｔ）方式、ＰＶＡ（Ｐａｔｔｅｒｎｅｄ　Ｖｅｒｔｉｃａｌ　Ａｌｉｇｎｍｅｎｔ）方式、ＯＣＢ（Ｏｐｔｉｃａｌｌｙ　Ｃｏｍｐｅｎｓａｔｅｄ　Ｂｅｎｄ）方式、ＨＡＮ（Ｈｙｂｒｉｄ　Ａｌｉｇｎｅｄ　Ｎｅｍａｔｉｃ）方式、ＡＳＭ（Ａｘｉａｌｌｙ　Ｓｙｍｍｅｔｒｉｃ　Ａｌｉｇｎｅｄ　Ｍｉｃｒｏｃｅｌｌ）方式、ハーフトーングレイスケール方式、ドメイン分割方式、あるいは強誘電性液晶、反強誘電性液晶を利用した表示方式等の各種の方式が挙げられる。 As the liquid crystal cell method, a TN (Twisted Nematic) method, a STN (Super Twisted Nematic) method, an ECB (Electrically Controlled Birefringence) method, an IPS (In-Plane Switching) method, a VA (In-Plane Switching) method, a VA (In-Plane Switching) method, a VA (In-Plane Switching) method, and a VA (In-Plane Switching) method. Vertical Alignment (PVA), PVA (Patterned Vertical Alignment), OCB (Optically Compensated Bend), HAN (Hybrid Aligned Nematic), ASM Ocell) method, a halftone gray scale method, the domain division method or a ferroelectric liquid crystal, various methods such as a display system using an antiferroelectric liquid crystal and the like.
　また、液晶セルの駆動方式も特に制限はなく、ＳＴＮ－ＬＣＤ等に用いられるパッシブマトリクス方式、並びにＴＦＴ（Ｔｈｉｎ　Ｆｉｌｍ　Ｔｒａｎｓｉｓｔｏｒ）電極、ＴＦＤ（Ｔｈｉｎ　Ｆｉｌｍ　Ｄｉｏｄｅ）電極等の能動電極を用いるアクティブマトリクス方式、プラズマアドレス方式等のいずれの駆動方式であってもよい。カラーフィルターを使用しないフィールドシーケンシャル方式であってもよい。 In addition, the liquid crystal cell driving method is not particularly limited, and a passive matrix method used for STN-LCD and the like, and an active matrix method using an active electrode such as a TFT (Thin Film Transistor) electrode and a TFD (Thin Film Diode) electrode, Any driving method such as a plasma addressing method may be used. A field sequential method that does not use a color filter may be used.
　本発明の偏光板は、反射型、半透過型、及び透過型液晶表示装置に好ましく用いられる。反射型液晶表示装置は、通常、反射板、液晶セル及び偏光板を、この順に積層した構成を有する。位相差板は、反射板と偏光子との間（反射板と液晶セルとの間又は液晶セルと偏光子との間）に配置される。 The polarizing plate of the present invention is preferably used for reflective, transflective, and transmissive liquid crystal display devices. A reflective liquid crystal display device usually has a configuration in which a reflector, a liquid crystal cell, and a polarizing plate are laminated in this order. The retardation plate is disposed between the reflector and the polarizer (between the reflector and the liquid crystal cell or between the liquid crystal cell and the polarizer).
　反射板は、液晶セルと基板を共有していてもよい。前記偏光板として、本発明の偏光板を用いることができ、かかる場合は、位相差板を別途配置しなくてもよい。 The reflective plate may share the liquid crystal cell and the substrate. As the polarizing plate, the polarizing plate of the present invention can be used. In such a case, the retardation plate may not be separately provided.
　また、半透過反射型液晶表示装置は、液晶セルと、該液晶セルより観察者側に配置された偏光板と、前記偏光板と前記液晶セルの間に配置される少なくとも１枚の位相差板と、観察者から見て前記液晶層よりも後方に設置された半透過反射層を少なくとも備え、さらに観察者から見て前記半透過反射層よりも後方に少なくとも１枚の位相差板と偏光板とを有す。 The transflective liquid crystal display device includes a liquid crystal cell, a polarizing plate disposed on the viewer side of the liquid crystal cell, and at least one retardation plate disposed between the polarizing plate and the liquid crystal cell. And at least one transflective layer disposed behind the liquid crystal layer as viewed from the viewer, and at least one retardation plate and polarizing plate behind the transflective layer as viewed from the viewer And have.
　このタイプの液晶表示装置では、バックライトを設置することで反射モードと透過モード両方の使用が可能となる。双方の偏光板が本発明の偏光板であってもよいし、一方のみが本発明の偏光板であってもよい。 This type of liquid crystal display device can be used in both reflection mode and transmission mode by installing a backlight. Both polarizing plates may be the polarizing plate of the present invention, or only one of them may be the polarizing plate of the present invention.
　本発明の偏光板を配置する場合は、液晶セルと本発明の偏光板との間には、位相差板を別途配置しなくてもよい。 When the polarizing plate of the present invention is disposed, a retardation plate may not be separately disposed between the liquid crystal cell and the polarizing plate of the present invention.
　液晶セルのモードは、特に限定されないが、ＩＰＳモード又はＦＦＳモードであることが好ましい。 The mode of the liquid crystal cell is not particularly limited, but is preferably an IPS mode or an FFS mode.
　ＩＰＳモードの液晶セルは、棒状液晶分子が基板に対して実質的に平行に配向しており、基板面に平行な電界が印加することで液晶分子が平面的に応答する。 In the IPS mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially parallel to the substrate, and the liquid crystal molecules respond in a planar manner when an electric field parallel to the substrate surface is applied.
　ＩＰＳモードは電界無印加状態で黒表示となり、上下一対の偏光板の透過軸は直交している。位相差フィルムを用いて、斜め方向での黒表示時の漏れ光を低減させ、視野角を改良する方法が、特開平１０－５４９８２号公報、特開平１１－２０２３２３号公報、特開平９－２９２５２２号公報、特開平１１－１３３４０８号公報、特開平１１－３０５２１７号公報、特開平１０－３０７２９１号公報などに開示されている。 IPS mode is black when no electric field is applied, and the transmission axes of a pair of upper and lower polarizing plates are orthogonal. JP-A-10-54982, JP-A-11-202323, and JP-A-9-292522 are methods for reducing leakage light during black display in an oblique direction and improving a viewing angle using a retardation film. No. 11-133408, No. 11-305217, No. 10-307291, and the like.
　例えば、前記第１の態様の偏光板を、一対の基板と、該一対の基板に狭持された液晶分子が黒表示時に基板に対して実質的に平行に配向する液晶層とを有する液晶セル（例えば、ＩＰＳモードの液晶セル）を有する液晶表示装置に用いる場合は、前記一対の基板の一方の基板の外側に該基板側から、第１光学異方性層、第２光学異方性層、及び偏光子がこの順となり、且つ該第２光学異方性層の遅相軸と黒表示時の液晶分子の長軸方向とが実質的に平行になるように前記偏光板を配置し、及び他方の基板の外側にさらに第２偏光子を配置することができる。この場合、双方の偏光子の吸収軸を互いに直交させて配置する。 For example, the polarizing plate according to the first aspect includes a pair of substrates and a liquid crystal cell in which liquid crystal molecules sandwiched between the pair of substrates are aligned substantially parallel to the substrate during black display. When used in a liquid crystal display device having a liquid crystal cell (for example, an IPS mode liquid crystal cell), the first optical anisotropic layer and the second optical anisotropic layer are formed on the outer side of one of the pair of substrates from the substrate side. And the polarizer is arranged in this order, and the polarizing plate is arranged so that the slow axis of the second optically anisotropic layer and the major axis direction of the liquid crystal molecules during black display are substantially parallel, In addition, a second polarizer can be further disposed outside the other substrate. In this case, the absorption axes of both polarizers are arranged so as to be orthogonal to each other.
　また、前記第２の態様の偏光板を、一対の基板と、該一対の基板に狭持された液晶分子が黒表示時に基板に対して実質的に平行に配向する液晶層とを有する液晶セル（例えば、ＩＰＳモードの液晶セル）を有する液晶表示装置に用いる場合は、前記一対の基板の一方の基板の外側に該基板側から、第２光学異方性層、第１光学異方性層、及び偏光子がこの順となり、且つ該第２光学異方性層の遅相軸と黒表示時の液晶分子の長軸方向とが実質的に直交するように前記偏光板を配置し、及び他方の基板の外側にさらに第２偏光子を配置することができる。 The polarizing plate of the second aspect includes a pair of substrates and a liquid crystal layer in which liquid crystal molecules sandwiched between the pair of substrates are aligned substantially parallel to the substrate during black display. When used in a liquid crystal display device having an IPS mode liquid crystal cell (for example, an IPS mode liquid crystal cell), the second optical anisotropic layer and the first optical anisotropic layer are formed on the outside of one of the pair of substrates from the substrate side. And the polarizer is arranged in this order, and the polarizing plate is arranged so that the slow axis of the second optically anisotropic layer and the major axis direction of the liquid crystal molecules at the time of black display are substantially perpendicular to each other, and A second polarizer can be further arranged outside the other substrate.
　この場合、双方の偏光子の吸収軸が互いに直交させて配置する。この場合も、双方の偏光子の吸収軸を互いに直交させて配置する。 In this case, the polarizers are arranged so that the absorption axes of both polarizers are orthogonal to each other. Also in this case, both polarizers are arranged so that the absorption axes thereof are orthogonal to each other.
　前記いずれの態様においても、前記第２偏光子と前記基板との間には実質的に等方的な接着層、及び／又は実質的に等方的な透明保護フィルムのみが含まれているのが好ましい。 In any of the aspects, only a substantially isotropic adhesive layer and / or a substantially isotropic transparent protective film is included between the second polarizer and the substrate. Is preferred.
　以下に実施例と比較例を挙げて本発明の特徴をさらに具体的に説明する。以下の実施例に示す材料、使用量、割合、処理内容、処理手順等は、本発明の趣旨を逸脱しない限り適宜変更することができる。 Hereinafter, the features of the present invention will be described more specifically with reference to examples and comparative examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention.
　実施例１
　＜第２光学異方性層としてのフィルム（Ｂ１）～（Ｂ４）の作製＞
　（第２光学異方性層（Ｂ１））
　第２光学異方性層（Ｂ１）に対応するセルロースエステルフィルムを以下のように作製した。 Example 1
<Production of Films (B1) to (B4) as Second Optically Anisotropic Layer>
(Second optically anisotropic layer (B1))
A cellulose ester film corresponding to the second optically anisotropic layer (B1) was produced as follows.
　まず、以下の組成のドープ（セルロースエステル溶液）を調製した。 First, a dope (cellulose ester solution) having the following composition was prepared.
　（セルロースエステルドープ組成物）
　セルロースアセテートプロピオネートＣＥ１　　　　　　１００質量部
（アセチル基置換度（Ａ）１．９５、プロピオニル基置換度（Ｂ）０．７）
　トリフェニルフォスフェート　　　　　　　　　　　　　　１０質量部
　エチルフタリルエチルグリコレート　　　　　　　　　　　　２質量部
　チヌビン３２６（チバ・ジャパン（株）製）　　　　　　　　１質量部
　ＡＥＲＯＳＩＬ　２００Ｖ（日本アエロジル（株）製）　０．１質量部
　メチレンクロライド　　　　　　　　　　　　　　　　　３００質量部
　エタノール　　　　　　　　　　　　　　　　　　　　　　４０質量部
　上記組成物を、加熱しながら十分に溶解し、ドープ液を作製した。 (Cellulose ester dope composition)
Cellulose acetate propionate CE1 100 parts by mass (acetyl group substitution degree (A) 1.95, propionyl group substitution degree (B) 0.7)
Triphenyl phosphate 10 parts by weight Ethylphthalylethyl glycolate 2 parts by weight Tinuvin 326 (manufactured by Ciba Japan) 1 part by weight AEROSIL 200V (manufactured by Nippon Aerosil Co., Ltd.) 0.1 part by weight Methylene chloride 300 parts by weight Ethanol 40 parts by mass The above composition was sufficiently dissolved while heating to prepare a dope solution.
　このドープ液を、ベルト流延装置を用い、温度２２℃、２ｍ幅でステンレスバンド支持体に均一に流延した。ステンレスバンド支持体で、残留溶剤量が１００％になるまで溶媒を蒸発させ、剥離張力１６２Ｎ／ｍでステンレスバンド支持体上から剥離した。 The dope solution was uniformly cast on a stainless steel band support at a temperature of 22 ° C. and a width of 2 m using a belt casting apparatus. With the stainless steel band support, the solvent was evaporated until the amount of residual solvent reached 100%, and peeling was performed from the stainless steel band support with a peeling tension of 162 N / m.
　剥離したフィルム材料のウェブを３５℃で溶媒を蒸発させ、１．６ｍ幅にスリットし、その後、テンターで幅方向（ＴＤ）に１．４倍に延伸しながら、１６５℃の乾燥温度で乾燥させた。 The web of the peeled film material was evaporated at 35 ° C., slit to 1.6 m width, and then dried at a drying temperature of 165 ° C. while being stretched 1.4 times in the width direction (TD) with a tenter. It was.
　このときテンターで延伸を始めたときの残留溶剤量は１０％であった。 At this time, the residual solvent amount when starting stretching with a tenter was 10%.
　テンターで延伸後、１５０℃で５分間緩和を行った後、１４０℃、１３５℃の乾燥ゾーンを多数のロールで搬送させながら乾燥を終了させ、１．５ｍ幅にスリットし、フィルム両端に幅１０ｍｍ高さ５μｍのナーリング加工を施し、初期張力２２０Ｎ／ｍ、終張力１１５Ｎ／ｍで内径６インチコアに巻き取り、光学異方性層としてのフィルムＣＥ１を得た。 After stretching with a tenter, relaxation was performed at 150 ° C. for 5 minutes, and then drying was completed while conveying a drying zone of 140 ° C. and 135 ° C. with many rolls, slitting to a width of 1.5 m, and a width of 10 mm at both ends of the film A knurling process having a height of 5 μm was performed, and the film was wound around a 6-inch inner diameter core with an initial tension of 220 N / m and a final tension of 115 N / m to obtain a film CE1 as an optically anisotropic layer.
　ステンレスバンド支持体の回転速度とテンターの運転速度から算出される製膜方向（ＭＤ）の延伸倍率は１．０２倍であった。 The draw ratio in the film forming direction (MD) calculated from the rotational speed of the stainless steel band support and the operating speed of the tenter was 1.02.
　表２記載の光学異方性層としてのフィルムＣＥ１の残留溶剤量は０．１％であり、膜厚は６０μｍ、であった。 The residual solvent amount of the film CE1 as an optically anisotropic layer described in Table 2 was 0.1%, and the film thickness was 60 μm.
　フィルムＢ１を作製するときの延伸倍率、延伸温度を代えて、表１記載のようにして、その他は同様にして、フィルムＢ２、フィルムＢ３を作製した。 A film B2 and a film B3 were prepared in the same manner as described in Table 1, except that the draw ratio and the draw temperature when producing the film B1 were changed.
　＜第２光学異方性層（Ｂ４）の作製＞
　　（溶解（ドープの調製））
　ＣＥ１のセルロースアセテートプロピオネート樹脂を代えて、アセチル基の置換度２．８５のセルロースアセテート樹脂であるＣＥ２に変更して、下記構成の材料を加熱しながら十分に溶解し、ドープ液を作製した。 <Production of Second Optically Anisotropic Layer (B4)>
(Dissolution (preparation of dope))
The cellulose acetate propionate resin of CE1 was replaced with CE2 which is a cellulose acetate resin having a substitution degree of acetyl group of 2.85, and the materials having the following constitution were sufficiently dissolved while heating to prepare a dope solution. .
　セルロースアセテートＣＥ２　　　　　　　　　　　　　１００質量部
（アセチル基置換度２．８５）
　トリフェニルフォスフェート（ＴＰＰ）　　　　　　　　７．８質量部
　ビフェニルジフェニルホスフェート（ＢＤＰ）　　　　　３．９質量部
　下記リターデーション上昇剤　　　　　　　　　　　　　５．０質量部
　チヌビン３２６（チバ・ジャパン（株）製）　　　　　　１．０質量部
　マット剤（二酸化ケイ素（一次粒子径２０ｎｍ）、モース硬度　約７）
　　　　　　　　　　　　　　　　　　　　　　　　　　０．０５質量部
　メチレンクロライド　　　　　　　　　　　　　　　　　３００質量部
　メタノール　　　　　　　　　　　　　　　　　　　　　　５４質量部
　１－ブタノール　　　　　　　　　　　　　　　　　　　　１１質量部
　フィルムの製膜は、フィルムＢ１～３と同様に、表１記載の延伸倍率、延伸温度を代えて、その他は同様にして本発明に用いるフィルムＢ４～フィルムＢ６、及び比較のフィルムＢ７を作製した。また、その他比較として市販のコニカミノルタオプト（株）製ＫＣ８ＵＸ、同４ＵＹを準備した。 Cellulose acetate CE2 100 parts by mass (acetyl group substitution degree 2.85)
Triphenyl phosphate (TPP) 7.8 parts by mass Biphenyl diphenyl phosphate (BDP) 3.9 parts by mass The following retardation increasing agent 5.0 parts by mass Tinuvin 326 (manufactured by Ciba Japan Co., Ltd.) 1.0 part by mass Matt Agent (silicon dioxide (primary particle diameter 20 nm), Mohs hardness about 7)
0.05 parts by weight Methylene chloride 300 parts by weight Methanol 54 parts by weight 1-butanol 11 parts by weight The film was formed in the same manner as the films B1 to 3, except that the draw ratios and stretch temperatures shown in Table 1 were changed. Thus, films B4 to B6 used in the present invention and comparative film B7 were produced. As other comparisons, commercially available Konica Minolta Opto KC8UX and 4UY were prepared.
　別の比較フィルムであるゼオノアフィルムは、脂環式オレフィン樹脂（ガラス転移温度１３６℃）からなる厚さ２００μｍのフィルム（オプテス社製、ゼオノアフィルムＺＦ－１４）を、同時二軸延伸機を使用して、オーブン温度（予熱温度、延伸温度、熱固定温度）１３８℃、フィルムの繰り出し速度１ｍ／分、縦延伸倍率１．６倍、横延伸倍率１．７倍で同時二軸延伸を行い、厚さ６５μｍの脂環式オレフィン樹脂フィルムのゼオノア１を延伸して作製し、同様に表１記載のように変更してゼオノア２を作製した。 Another comparative film, ZEONOR film, is a 200 μm thick ZEONOR film ZF-14 made of alicyclic olefin resin (glass transition temperature 136 ° C.) using a simultaneous biaxial stretching machine. The film is simultaneously biaxially stretched at an oven temperature (preheating temperature, stretching temperature, heat setting temperature) of 138 ° C., a film feeding speed of 1 m / min, a longitudinal stretching ratio of 1.6 times, and a transverse stretching ratio of 1.7 times. A 65 μm alicyclic olefin resin film of ZEONOR 1 was drawn and produced, and similarly changed as shown in TABLE 1 to produce ZEONOR 2.
Figure JPOXMLDOC01-appb-C000015
Figure JPOXMLDOC01-appb-C000015
Figure JPOXMLDOC01-appb-T000016
Figure JPOXMLDOC01-appb-T000016
　実施例２
　＜第１光学異方性層としてのフィルム（Ｐ１）～（Ｐ４）の作製＞
　（第１光学異方性層（Ｐ１））
　以下のアクリル樹脂Ａ１－Ａ３を公知の方法によって作製した。 Example 2
<Production of Films (P1) to (P4) as First Optical Anisotropic Layer>
(First optical anisotropic layer (P1))
The following acrylic resins A1-A3 were prepared by a known method.
　Ａ１：ポリ（ＭＭＡ－Ｓｔ）質量比６０：４０　Ｍｗ３０００００
　Ａ２：ポリ（ＭＭＡ－Ｓｔ－ＡＮ）質量比５５：３５：１０　Ｍｗ３０００００
　Ａ３：ポリ（ＭＭＡ－ＣＨＭＩ－Ｓｔ－ＡＮ）
　質量比９０：５：５：５　Ｍｗ１４００００
　ＭＭＡ：メチルメタクリレート
　Ｓｔ：スチレン
　ＡＮ：アクリロニトリル
　ＣＨＭＩ：シクロヘキシルマレイミド
　〈光学フィルムＰ１の作製〉
　（ドープ液組成）
　アクリル樹脂Ａ２　　　　　　　　　　　　　　　　　　　７９質量部
　ＣＡＰ４８２－２０（アシル基総置換度２．７５、アセチル基置換度０．１９、プロピオニル基置換度２．５６、Ｍｗ＝２０００００　イーストマンケミカル（株）製）　　　　　　　　　　　　　　　　　　　２０質量部
下記で調製したアクリル粒子（Ｃ１）　　　　　　　　　　　　１質量部
　メチレンクロライド　　　　　　　　　　　　　　　　　３００質量部
　エタノール　　　　　　　　　　　　　　　　　　　　　　４０質量部
　上記組成物を、加熱しながら十分に溶解し、ドープ液を作製した。 A1: Poly (MMA-St) mass ratio 60:40 Mw 300000
A2: Poly (MMA-St-AN) mass ratio 55:35:10 Mw 300000
A3: Poly (MMA-CHMI-St-AN)
Mass ratio 90: 5: 5: 5 Mw 140000
MMA: Methyl methacrylate St: Styrene AN: Acrylonitrile CHMI: Cyclohexylmaleimide <Production of optical film P1>
(Dope solution composition)
Acrylic resin A2 79 parts by mass CAP482-20 (acyl group total substitution degree 2.75, acetyl group substitution degree 0.19, propionyl group substitution degree 2.56, Mw = 200000 manufactured by Eastman Chemical Co., Ltd.) 20 parts by mass Acrylic particles (C1) prepared in 1 part by weight Methylene chloride 300 parts by weight Ethanol 40 parts by weight The above composition was sufficiently dissolved while heating to prepare a dope solution.
　〈アクリル粒子（Ｃ１）の調製〉
　内容積６０リットルの還流冷却器付反応器に、イオン交換水３８．２リットル、ジオクチルスルホコハク酸ナトリウム１１１．６ｇを投入し、２５０ｒｐｍの回転数で攪拌しながら、窒素雰囲気下７５℃に昇温し、酸素の影響が事実上無い状態にした。ＡＰＳ０．３６ｇを投入し、５分間攪拌後にＭＭＡ１６５７ｇ、ＢＡ２１．６ｇ、及びＡＬＭＡ１．６８ｇからなる単量体混合物を一括添加し、発熱ピークの検出後さらに２０分間保持して最内硬質層の重合を完結させた。 <Preparation of acrylic particles (C1)>
A reactor with a reflux condenser with an internal volume of 60 liters was charged with 38.2 liters of ion-exchanged water and 111.6 g of sodium dioctylsulfosuccinate, and the temperature was raised to 75 ° C. in a nitrogen atmosphere while stirring at 250 rpm. The effect of oxygen was virtually eliminated. 0.36 g of APS was added, and after stirring for 5 minutes, a monomer mixture consisting of MMA 1657 g, BA 21.6 g, and ALMA 1.68 g was added all at once, and after the detection of the exothermic peak, it was held for another 20 minutes to polymerize the innermost hard layer. Completed.
　次に、ＡＰＳ３．４８ｇを投入し、５分間攪拌後にＢＡ８１０５ｇ、ＰＥＧＤＡ（２００）３１．９ｇ、及びＡＬＭＡ２６４．０ｇからなる単量体混合物を１２０分間かけて連続的に添加し、添加終了後さらに１２０分間保持して，軟質層の重合を完結させた。 Next, 3.48 g of APS was added, and after stirring for 5 minutes, a monomer mixture composed of 8105 g of BA, 31.9 g of PEGDA (200) and 264.0 g of ALMA was continuously added over 120 minutes. Hold for a minute to complete the soft layer polymerization.
　次に、ＡＰＳ１．３２ｇを投入し、５分間攪拌後にＭＭＡ２１０６ｇ、ＢＡ２０１．６ｇからなる単量体混合物を２０分間かけて連続的に添加し、添加終了後さらに２０分間保持して最外硬質層１の重合を完結した。 Next, 1.32 g of APS was added, and after stirring for 5 minutes, a monomer mixture consisting of 2106 g of MMA and 201.6 g of BA was continuously added over 20 minutes. The polymerization of was completed.
　次いで、ＡＰＳ１．３２ｇを投入し、５分後にＭＭＡ３１４８ｇ、ＢＡ２０１．６ｇ、及びｎ－ＯＭ１０．１ｇからなる単量体混合物を２０分間かけて連続的に添加し、添加終了後にさらに２０分間保持した。ついで９５℃に昇温し６０分間保持して、最外硬質層２の重合を完結させた。 Next, 1.32 g of APS was added, and after 5 minutes, a monomer mixture consisting of 3148 g of MMA, 201.6 g of BA, and 10.1 g of n-OM was continuously added over 20 minutes, and the mixture was held for another 20 minutes after the addition was completed. Next, the temperature was raised to 95 ° C. and held for 60 minutes to complete the polymerization of the outermost hard layer 2.
　このようにして得られた重合体ラテックスを少量採取し、吸光度法により平粒子径を求めたところ０．１０μｍであった。残りのラテックスを３質量％硫酸ナトリウム温水溶液中へ投入して、塩析・凝固させ、次いで、脱水・洗浄を繰り返したのち乾燥し、３層構造のアクリル粒子（Ｃ１）を得た。 A small amount of the polymer latex thus obtained was collected, and the flat particle size was determined by the absorbance method, which was 0.10 μm. The remaining latex was put into a 3% by mass sodium sulfate warm aqueous solution, salted out and coagulated, and then dried after repeated dehydration and washing to obtain acrylic particles (C1) having a three-layer structure.
　上記の略号は各々下記材料である。 The above abbreviations are the following materials.
　ＭＭＡ；メチルメタクリレート
　ＭＡ；メチルアクリレート
　ＢＡ；ｎ－ブチルアクリレート
　ＡＬＭＡ；アリルメタクリレート
　ＰＥＧＤＡ；ポリエチレングリコールジアクリレート（分子量２００）
　ｎ－ＯＭ；ｎ－オクチルメルカプタン
　ＡＰＳ；過硫酸アンモニウム
　（光学フィルムＰ１の製膜）
　上記作製したドープ液を、ベルト流延装置を用い、温度２２℃、２ｍ幅でステンレスバンド支持体に均一に流延した。ステンレスバンド支持体で、残留溶剤量が１００％になるまで溶媒を蒸発させ、剥離張力１６２Ｎ／ｍでステンレスバンド支持体上から剥離した。 MMA; methyl methacrylate MA; methyl acrylate BA; n-butyl acrylate ALMA; allyl methacrylate PEGDA; polyethylene glycol diacrylate (molecular weight 200)
n-OM; n-octyl mercaptan APS; ammonium persulfate (formation of optical film P1)
The produced dope liquid was uniformly cast on a stainless steel band support at a temperature of 22 ° C. and a width of 2 m using a belt casting apparatus. With the stainless steel band support, the solvent was evaporated until the residual solvent amount reached 100%, and the film was peeled off from the stainless steel band support with a peeling tension of 162 N / m.
　剥離したアクリル樹脂のウェブを３５℃で溶媒を蒸発させ、１．６ｍ幅にスリットし、その後、テンターで幅方向（ＴＤ方向）に１．３５倍に延伸しながら、１３５℃の乾燥温度で乾燥させた。 The peeled acrylic resin web was evaporated at 35 ° C., slit to 1.6 m width, and then dried at a drying temperature of 135 ° C. while being stretched 1.35 times in the width direction (TD direction) with a tenter. I let you.
　このときテンターで延伸を始めたときの残留溶剤量は１０％であった。 At this time, the residual solvent amount when starting stretching with a tenter was 10%.
　テンターで延伸後１４０℃で５分間緩和を行った後、１３０℃、１２０℃の乾燥ゾーンを多数のロールで搬送させながら乾燥を終了させ、１．５ｍ幅にスリットし、フィルム両端に幅１０ｍｍ高さ５μｍのナーリング加工を施し、初期張力２２０Ｎ／ｍ、終張力１１５Ｎ／ｍで内径６インチコアに巻き取り、光学フィルムＰ１を得た。 After stretching with a tenter, relaxation was performed at 140 ° C for 5 minutes, and then drying was completed while transporting the 130 ° C and 120 ° C drying zones with a number of rolls, slitting to a width of 1.5 m, and 10 mm wide at both ends of the film. A 5 μm knurling process was performed, and the film was wound around a 6-inch inner diameter core with an initial tension of 220 N / m and a final tension of 115 N / m to obtain an optical film P1.
　ステンレスバンド支持体の回転速度とテンターの運転速度から算出される製膜方向（ＭＤ）の延伸倍率は１．３倍であった。 The draw ratio in the film forming direction (MD) calculated from the rotational speed of the stainless steel band support and the operating speed of the tenter was 1.3 times.
　表２記載の光学フィルムＰ１の残留溶剤量は０．１％であり、膜厚は４０μｍであった。 The residual solvent amount of the optical film P1 described in Table 2 was 0.1%, and the film thickness was 40 μm.
　以下、アクリル樹脂（Ａ１～Ａ３）、セルロースエステル樹脂（「セルロース樹脂」と略記する。）、アクリル粒子Ｃ１の組成比を表２記載のように変えた以外は、光学フィルムＰ１と同様にして、光学フィルムＰ２～Ｐ５を作製した。 Hereinafter, except for changing the composition ratio of the acrylic resins (A1 to A3), cellulose ester resin (abbreviated as “cellulose resin”), and acrylic particles C1 as shown in Table 2, the same as the optical film P1, Optical films P2 to P5 were produced.
Figure JPOXMLDOC01-appb-T000017
Figure JPOXMLDOC01-appb-T000017
　（リターデーションＲｏ（１）及びＲｔ（１）の測定）
　上記作製した各々のフィルム試料を、２３℃、５５％ＲＨの空調室で２４時間調湿した後、同条件下において、位相差測定装置ＫＯＢＲＡ－２１ＡＤＨ（王子計測機器（株））を用いて測定し、アッベ屈折率計で同環境かつ５９０ｎｍで測定した平均屈折率及びノギスで測定したフィルムの膜厚を入力して、波長５９０ｎｍのリターデーションを求めた。 (Measurement of retardation Ro (1) and Rt (1))
Each film sample prepared above was conditioned for 24 hours in an air-conditioned room at 23 ° C. and 55% RH, and measured under the same conditions using a phase difference measuring device KOBRA-21ADH (Oji Scientific Instruments). Then, the average refractive index measured with the Abbe refractometer in the same environment and 590 nm and the film thickness of the film measured with calipers were input to obtain retardation at a wavelength of 590 nm.
　実施例３
　＜偏光板（ＰＬ１～ＰＬ１３）の作製＞
　厚さ１２０μｍの長尺ロールポリビニルアルコールフイルムを沃素１質量部、ホウ酸４質量部を含む水溶液１００質量部に浸漬し、５０℃で５倍に搬送方向に延伸して乾燥して偏光子を作った。 Example 3
<Production of polarizing plates (PL1 to PL13)>
A 120-μm long roll of polyvinyl alcohol film is immersed in 100 parts by mass of an aqueous solution containing 1 part by mass of iodine and 4 parts by mass of boric acid, stretched in the transport direction 5 times at 50 ° C., and dried to make a polarizer. It was.
　この片面に下記ウレタン樹脂系の水性エマルションを接着剤として、第２光学異方性層であるフィルムＢ３の片面にコロナ処理を施して同水性エマルションを偏光子と貼合するために接着剤として用いる。 The following urethane resin-based aqueous emulsion is used as an adhesive on one side, and one side of film B3, which is the second optically anisotropic layer, is subjected to corona treatment and used as an adhesive to bond the aqueous emulsion with a polarizer. .
　ウレタン樹脂の水性エマルジョン
（大日本インキ化学工業（株）製ハイドランＡＰ－２０）　１００質量部
　多官能グリシジルエーテル（大日本インキ化学工業（株）製ＣＲ－５Ｌ）　　　　　　　　　　　　　　　　　　　　　　　　　　　　　５質量部
　更に偏光子のもう一方の面にアルカリケン化処理したＴＡＣフィルムであるコニカミノルタオプト（株）製ＫＣ４ＵＹをポリビニルアルコール系接着剤を用いて、偏光子の対向側にはフィルムＢ３を配置し、コロナ処理した面に上記エマルションが塗設できるように配置し、常法に従って、両フィルムを同時に貼り合わせ、乾燥して偏光板ＰＬ１を作製した。 Aqueous emulsion of urethane resin (Hydran AP-20, manufactured by Dainippon Ink & Chemicals, Inc.) 100 parts by mass Polyfunctional glycidyl ether (CR-5L, manufactured by Dainippon Ink & Chemicals, Inc.) 5 parts by mass The other side of the polarizer KAC4UY made by Konica Minolta Opto Co., Ltd., which is a TAC film subjected to alkali saponification treatment on the surface of the film, a film B3 is disposed on the opposite side of the polarizer using the polyvinyl alcohol adhesive, and the emulsion is applied on the surface subjected to corona treatment. The two films were bonded together and dried according to a conventional method to prepare polarizing plate PL1.
　このとき、貼り合わせにおいては、ローラーで偏光子と両面に各々１枚ずつの偏光板保護フィルムである光学フィルムＢとＴＡＣフィルムである４ＵＹとの積層物の端から過剰の接着剤と水を主体とした溶媒及び気泡を取り除き貼り合わせた。ローラーの圧力は２０～３０Ｎ／ｃｍ２、スピードは約２ｍ／分で貼合した。次いで、８０℃の乾燥機中に前記貼り合わせた試料を７分間乾燥して、偏光板ＰＬ１の土台を作製した。続いて、光学フィルムＰ１をＰＬ１の土台に接着するために、光学フィルムＢ３側にコロナ処理を施したのち、次いで光学フィルムＰ１をＰＬ１の土台に接着する面にコロナ処理を行い、構成１が成り立つように、上記ウレタン樹脂の水性エマルジョンを接着剤として用いて上述と同様に貼合して乾燥することで、光学フィルムＰ１がＰＬ１の土台に接着されたロール状偏光板ＰＬ１を作製した。 At this time, in bonding, an adhesive and water are mainly formed from the end of the laminate of the polarizer and the optical film B which is a polarizing plate protective film on each side and 4UY which is a TAC film. The solvent and bubbles were removed and pasted together. Bonding was performed at a roller pressure of 20 to 30 N / cm 2 and a speed of about 2 m / min. Next, the bonded sample was dried for 7 minutes in a dryer at 80 ° C. to prepare the base of the polarizing plate PL1. Subsequently, in order to bond the optical film P1 to the base of PL1, the optical film B3 side is subjected to a corona treatment, and then the surface of the optical film P1 to be bonded to the base of PL1 is subjected to a corona treatment. Thus, the roll-shaped polarizing plate PL1 by which the optical film P1 was adhere | attached on the base of PL1 was produced by bonding and drying similarly to the above using the aqueous | water-based emulsion of the said urethane resin as an adhesive agent.
　第２光学異方性層であるフィルムＢ３を表３記載のフィルムに代えて、また第１光学異方性層であるフィルムＰ１に代えて表３記載のフィルムに代えることで、偏光板ＰＬ２～偏光板ＰＬ１３を同様に作製した。 By replacing the film B3 which is the second optically anisotropic layer with the film described in Table 3, or by replacing the film B3 which is the first optically anisotropic layer with the film described in Table 3, A polarizing plate PL13 was produced in the same manner.
　このとき、偏光子の吸収軸は長手方向に対して平行であり、且つ、偏光子の吸収軸と第２光学異方性層（セルロースエステルフィルム）の遅相軸とがなす角は９０°であった。 At this time, the absorption axis of the polarizer is parallel to the longitudinal direction, and the angle formed by the absorption axis of the polarizer and the slow axis of the second optical anisotropic layer (cellulose ester film) is 90 °. there were.
　＜セルロースアセテートフィルム（Ｔ０）の作製＞
　下記の組成物をミキシングタンクに投入し、攪拌して各成分を溶解し、セルローストリアセテート溶液Ｕを調製した。
（セルローストリアセテート溶液Ｕの調製）
　アセチル置換度２．９４のセルローストリアセテート　　１００質量部
　メチレンクロライド（第１溶媒）　　　　　　　　　　　４０２質量部
　メタノール（第２溶媒）　　　　　　　　　　　　　　　　６０質量部
　（マット剤溶液の調製）
　平均粒径１６ｎｍのシリカ粒子（ＡＥＲＯＳＩＬ　Ｒ９７２、日本アエロジル（株）製）を２０質量部、メタノール８０質量部を３０分間よく攪拌混合してシリカ粒子分散液とした。 <Production of cellulose acetate film (T0)>
The following composition was put into a mixing tank and stirred to dissolve each component to prepare a cellulose triacetate solution U.
(Preparation of cellulose triacetate solution U)
Cellulose triacetate having a degree of acetyl substitution of 2.94 100 parts by mass Methylene chloride (first solvent) 402 parts by mass Methanol (second solvent) 60 parts by mass (Preparation of matting agent solution)
20 parts by mass of silica particles having an average particle diameter of 16 nm (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) and 80 parts by mass of methanol were mixed well for 30 minutes to obtain a silica particle dispersion.
　この分散液を下記の組成物とともに分散機に投入し、さらに３０分以上攪拌して各成分を溶解し、マット剤溶液を調製した。 This dispersion was charged into a disperser together with the following composition, and further stirred for 30 minutes or more to dissolve each component to prepare a matting agent solution.
　平均粒径１６ｎｍのシリカ粒子分散液　　　　　　　　１０．０質量部
　メチレンクロライド（第１溶媒）　　　　　　　　　　７６．３質量部
　メタノール（第２溶媒）　　　　　　　　　　　　　　　３．４質量部
　セルロースアセテート溶液Ｕ　　　　　　　　　　　　１０．３質量部
　（添加剤溶液の調製）
　下記の組成物をミキシングタンクに投入し、加熱しながら攪拌して、各成分を溶解し、セルロースアセテート溶液を調製した。 Silica particle dispersion liquid having an average particle diameter of 16 nm 10.0 parts by mass Methylene chloride (first solvent) 76.3 parts by mass Methanol (second solvent) 3.4 parts by mass Cellulose acetate solution U 10.3 parts by mass (additive solution) Preparation)
The following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution.
　下記の光学的異方性低下剤　　　　　　　　　　　　　４９．３質量部
　下記の波長分散調整剤　　　　　　　　　　　　　　　　４．９質量部
　メチレンクロライド（第１溶媒）　　　　　　　　　　５８．４質量部
　メタノール（第２溶媒）　　　　　　　　　　　　　　　８．７質量部
　セルローストリアセテート溶液Ｕ　　　　　　　　　　１２．８質量部 The following optical anisotropy reducing agent 49.3 parts by mass The following wavelength dispersion adjusting agent 4.9 parts by mass Methylene chloride (first solvent) 58.4 parts by mass Methanol (second solvent) 8.7 parts by mass Cellulose triacetate Solution U 12.8 parts by mass
Figure JPOXMLDOC01-appb-C000018
Figure JPOXMLDOC01-appb-C000018
　（セルローストリアセテートフィルムの作製）
　上記セルローストリアセテート溶液Ｕを９４．６質量部、マット剤溶液を１．３質量部、添加剤溶液４．１質量部それぞれを濾過後に混合し、バンド流延機を用いて流延した。 (Production of cellulose triacetate film)
94.6 parts by mass of the cellulose triacetate solution U, 1.3 parts by mass of the matting agent solution, and 4.1 parts by mass of the additive solution were mixed after filtration, and cast using a band casting machine.
　上記組成で光学的異方性を低下する化合物及び波長分散調整剤のセルロースアセテートに対する質量比はそれぞれ１２％、１．２％であった。 The mass ratio of the compound that reduces optical anisotropy in the above composition and the wavelength dispersion adjusting agent to cellulose acetate was 12% and 1.2%, respectively.
　残留溶剤量３０％でフィルムをバンドから剥離し、１４０℃で４０分間乾燥させ、厚さ８０μｍの長尺状のセルロースアセテートフィルムＴ０を製造した。得られたフィルムの面内リターデーション（Ｒｏ）は１ｎｍ（遅相軸はフィルム長手方向と垂直な方向）、厚さ方向のリターデーション（Ｒｔ）は－１ｎｍであった。 The film was peeled from the band with a residual solvent amount of 30% and dried at 140 ° C. for 40 minutes to produce a long cellulose acetate film T0 having a thickness of 80 μm. The in-plane retardation (Ro) of the obtained film was 1 nm (the slow axis was a direction perpendicular to the longitudinal direction of the film), and the retardation (Rt) in the thickness direction was −1 nm.
　＜偏光板（Ｐ０）の作製＞
　ヨウ素水溶液中で連続して染色した上記と同様のロール状ポリビニルアルコールフィルムを搬送方向に５倍延伸し、乾燥して接着することで長尺の偏光子を得た。 <Production of Polarizing Plate (P0)>
A roll-shaped polyvinyl alcohol film similar to the above dyed continuously in an aqueous iodine solution was stretched 5 times in the transport direction, dried and bonded to obtain a long polarizer.
　この偏光子の一方の面に鹸化処理した上記のセルロースアセテートフィルムＴ０を、他方の面に鹸化処理した市販のセルローストリアセテートフィルム（コニカミノルタタックＫＣ４ＵＹ、コニカミノルタオプト（株）製）を、ポリビニルアルコール系接着剤を用いて連続して貼り合わせ、乾燥してセルローストリアセテートフィルムが偏光子に接着された偏光板Ｐ０を作製した。 The cellulose acetate film T0 saponified on one side of this polarizer and the commercially available cellulose triacetate film (Konica Minolta Tack KC4UY, manufactured by Konica Minolta Opto) on the other side were polyvinyl alcohol-based. A polarizing plate P0 in which a cellulose triacetate film was bonded to a polarizer was prepared by continuously laminating using an adhesive and drying.
　実施例４
　＜液晶表示装置（Ｌ１）～（Ｌ４）の作製＞
　液晶テレビＴＨ－３２ＬＸ５００（松下電器産業（株）社製）から、液晶セルを取り出し、視認者側及びバックライト側に貼られてあった偏光板及び光学フィルムを剥した。この液晶セルは、電圧無印加状態及び黒表示時では液晶分子はガラス基板間で実質的に平行配向しており、その遅相軸方向は画面に対して水平方向であった。 Example 4
<Production of liquid crystal display devices (L1) to (L4)>
A liquid crystal cell was taken out from the liquid crystal television TH-32LX500 (manufactured by Matsushita Electric Industrial Co., Ltd.), and the polarizing plate and the optical film attached to the viewer side and the backlight side were peeled off. In this liquid crystal cell, when no voltage was applied and during black display, the liquid crystal molecules were aligned substantially in parallel between the glass substrates, and the slow axis direction was horizontal to the screen.
　上記の平行配向セルの上下のガラス基板に、上記作製した偏光板（ＰＬ１及びＰ０）を画面サイズの合うように断裁し、２０μｍの厚さとしたアクリル系粘着剤を偏光板上に設置して、後述の構成になるように粘着剤を介して液晶セルに貼り合わせた。このとき、バックライト側の偏光板にＰ０を配置し、視認者側にＰＬ１を配置し、偏光板ＰＬ１に含まれる第１光学異方性層が液晶セル側のガラス基板に接するように、また、偏光板Ｐ０に含まれるセルロースアセテートフィルムＴ０が液晶セル側のガラス基板に接するように貼り合わせた。 On the glass substrate above and below the parallel alignment cell, the produced polarizing plate (PL1 and P0) was cut so as to match the screen size, and an acrylic adhesive having a thickness of 20 μm was installed on the polarizing plate, It was bonded to the liquid crystal cell via an adhesive so as to have the configuration described later. At this time, P0 is disposed on the polarizing plate on the backlight side, PL1 is disposed on the viewer side, and the first optical anisotropic layer included in the polarizing plate PL1 is in contact with the glass substrate on the liquid crystal cell side. The cellulose acetate film T0 contained in the polarizing plate P0 was bonded so as to be in contact with the glass substrate on the liquid crystal cell side.
　このとき、偏光板ＰＬ１の吸収軸と液晶セルの遅相軸が直交し、かつ偏光板ＰＬ１と偏光板Ｐ０の吸収軸は直交した、構成１を満たす配置とした。 At this time, the absorption axis of the polarizing plate PL1 and the slow axis of the liquid crystal cell were orthogonal to each other, and the absorption axes of the polarizing plate PL1 and the polarizing plate P0 were orthogonal to satisfy the constitution 1.
　このようにして偏光板を貼り合せた液晶セルを、再度、液晶テレビＴＨ－３２ＬＸ５００に組み込みこんだ。このようにして液晶表示装置ＬＣＤ－１を作製した。 The liquid crystal cell with the polarizing plate attached in this way was incorporated into the liquid crystal television TH-32LX500 again. In this way, a liquid crystal display device LCD-1 was produced.
　上記の偏光板ＰＬ１を、それぞれ偏光板ＰＬ２～ＰＬ１３に変更し液晶表示装置ＬＣＤ２～ＬＣＤ１３を作製した。 The above polarizing plates PL1 were changed to polarizing plates PL2 to PL13, respectively, to prepare liquid crystal display devices LCD2 to LCD13.
　なお、上記の液晶表示装置ＬＣＤ２～ＬＣＤ４では液晶セル、第１光学異方性層、第２光学異方性層、偏光板層がこの順であり、第２光学異方性層の遅相軸と黒表示時の液晶分子の長軸方向とが実質的に平行であった。 In the above liquid crystal display devices LCD2 to LCD4, the liquid crystal cell, the first optical anisotropic layer, the second optical anisotropic layer, and the polarizing plate layer are in this order, and the slow axis of the second optical anisotropic layer. And the major axis direction of the liquid crystal molecules during black display were substantially parallel.
　＜液晶表示装置の評価＞
　（正面コントラスト）
　液晶表示装置を２３℃、５５％ＲＨで２４時間の環境で静置した、ＥＬＤＩＭ社製ＥＺ－Ｃｏｎｔｒａｓｔ１６０Ｄを用いて液晶表示装置の視野角測定を行った。 <Evaluation of liquid crystal display device>
(Front contrast)
The viewing angle of the liquid crystal display device was measured using EZ-Contrast 160D manufactured by ELDIM, in which the liquid crystal display device was allowed to stand at 23 ° C. and 55% RH for 24 hours.
　評価基準：
○：６００以上
△：５００以上
×：５００未満
△と○は実用上問題のないレベルである。 Evaluation criteria:
◯: 600 or more Δ: 500 or more ×: less than 500 Δ and ◯ are levels having no practical problem.
　〔コントラストムラ〕
　上記液晶表示パネルを４０℃８０％の条件下で強制劣化（耐久試験）を行い、それぞれの液晶表示パネルについて、５００時間処理した。 [Contrast unevenness]
The liquid crystal display panel was subjected to forced deterioration (durability test) under conditions of 40 ° C. and 80%, and each liquid crystal display panel was treated for 500 hours.
　液晶表示装置の視野角特性の評価をＥＬＤＩＭ社製ＥＺ－ｃｏｎｔｒａｓｔを用い黒表示及び白表示時の出射光量を測定した。視野角の評価はコントラスト＝（白表示時の透過光量）／（黒表示時の透過光量）を算出し下記基準にて評価を行った。 The evaluation of the viewing angle characteristics of the liquid crystal display device was performed by measuring the amount of emitted light during black display and white display using EZ-contrast manufactured by ELDIM. The viewing angle was evaluated by calculating contrast = (transmitted light amount during white display) / (transmitted light amount during black display) and evaluated according to the following criteria.
　視野角の評価は、コントラスト１０の視野角を示す角度を指標に評価を行った。 The viewing angle was evaluated using the angle indicating the viewing angle of contrast 10 as an index.
　上記液晶表示パネルを強制劣化（耐久試験）していない視野角と比較して、視野角の差を、液晶表示装置のコントラストムラとした。 The difference in viewing angle compared to the viewing angle where the liquid crystal display panel was not subjected to forced deterioration (endurance test) was defined as the contrast unevenness of the liquid crystal display device.
　評価基準：
◎：強制劣化前後のコントラストムラが全方位に対して５°以下である。
○：強制劣化前後のコントラストムラが方位に対して５°以上１０°未満となった部分が存在するが実用上問題ない。
△：強制劣化前後のコントラストムラが一部の方位に対して１０°以上１５°未満となった部分が存在し、表示画像にムラがある。
×：強制劣化前後のコントラストムラが一部の方位に対して１５°以上であり、かつ黒表示時の画像にムラがある。 Evaluation criteria:
A: Contrast unevenness before and after forced deterioration is 5 ° or less with respect to all directions.
○: There is a portion where the contrast unevenness before and after the forced deterioration is 5 ° or more and less than 10 ° with respect to the orientation, but there is no problem in practice.
Δ: There is a portion where the unevenness of contrast before and after the forced deterioration is 10 ° or more and less than 15 ° with respect to some orientations, and the display image is uneven.
X: Contrast unevenness before and after forced deterioration is 15 ° or more with respect to a part of the azimuth, and the image in black display is uneven.
　〈偏光子密着性〉
　作製した偏光板の密着性を以下の基準にて評価した。 <Polarizer adhesion>
The adhesion of the produced polarizing plate was evaluated according to the following criteria.
　各偏光板を各々５ｃｍ×７ｃｍのサイズに切断した。得られた切断片を各々６ｃｍ×８ｃｍのガラス板の中央部に２０μｍの厚さとしたアクリル系粘着剤で仮粘着し、次いでこれらを押圧して偏光板の切断片とガラス板の間の粘着層にある気泡を完全に除去するようにして偏光板の切断片を各々ガラス板に貼合した。 Each polarizing plate was cut into a size of 5 cm × 7 cm. The obtained cut pieces are temporarily adhered to the central part of each 6 cm × 8 cm glass plate with an acrylic adhesive having a thickness of 20 μm, and then pressed to be in an adhesive layer between the cut piece of the polarizing plate and the glass plate. Each piece of the polarizing plate was bonded to a glass plate so as to completely remove the bubbles.
　こうして作製した試験片を８０℃、９５％ＲＨにセットした恒温恒湿オーブン内に互いに重ならないように垂直に配して支持枠に１０００時間固定した後、各片について偏光子と保護フィルムの接着性の測定を行った。 The test pieces thus prepared were placed vertically in a constant temperature and humidity oven set at 80 ° C. and 95% RH so as not to overlap each other and fixed to the support frame for 1000 hours, and then the polarizer and the protective film were bonded to each piece. The sex was measured.
　偏光子と保護フィルムの接着性の評価：高温高湿処理後目視により観察を行い偏光子と保護フィルムの間の剥離状態を評価した。 Evaluation of adhesion between polarizer and protective film: After high-temperature and high-humidity treatment, visual observation was performed to evaluate the peeled state between the polarizer and the protective film.
　評価基準：
○：膜の浮き上がりの部分がまったく見当たらない
△：膜の浮き上がりの部分が周辺１～５ｍｍの範囲
×：膜の浮き上がりの部分が周辺５ｍｍ以上 Evaluation criteria:
○: The film lifted portion is not found at all. Δ: The film lifted portion is in the range of 1 to 5 mm in the periphery. ×: The film lifted portion is in the periphery of 5 mm or more.
Figure JPOXMLDOC01-appb-T000019
Figure JPOXMLDOC01-appb-T000019
Figure JPOXMLDOC01-appb-T000020
Figure JPOXMLDOC01-appb-T000020
　上記構成１の配置を構成２に変更しても、本発明の効果が同様に得られた。 The effect of the present invention was obtained in the same manner even when the arrangement of the configuration 1 was changed to the configuration 2.
　本発明の構成とリターデーションの範囲を満たすことで、液晶表示装置は高いコントラストが実現できると同時に、強制劣化試験を行ったときにコントラストムラの問題がなく、高い表示品質を与える。また、本発明に係る前記透湿度範囲内の透湿度をもつフィルムを偏光板として用いることで、偏光子の密着性に優れ、環境変動に安定な液晶表示装置が提供できる。 By satisfying the configuration and retardation range of the present invention, the liquid crystal display device can realize high contrast, and at the same time, there is no problem of unevenness of contrast when a forced deterioration test is performed, and high display quality is provided. Further, by using a film having a moisture permeability within the moisture permeability range according to the present invention as a polarizing plate, a liquid crystal display device having excellent polarizer adhesion and stable against environmental fluctuations can be provided.
　リターデーションが本発明の範囲から外れると、正面コントラストが低くなり表示品質が低くなる。第１光学異方性層と第２光学異方性層が接着剤によって貼合された偏光板であるので、透湿度が本発明に係る前記透湿度範囲を満たさないと各々のフィルムの環境変動性が異なるために、画面の場所によってコントラストムラが発生して表示品質が劣化し、環境変動によって偏光子と第２光学異方性層間の接着が低くなり、画像表示に悪影響を与えた。 If the retardation is out of the range of the present invention, the front contrast is lowered and the display quality is lowered. Since the first optically anisotropic layer and the second optically anisotropic layer are polarizing plates bonded with an adhesive, the environmental variation of each film unless the moisture permeability satisfies the moisture permeability range according to the present invention. Due to the difference in properties, contrast unevenness occurs depending on the location of the screen and the display quality deteriorates. Due to environmental changes, the adhesion between the polarizer and the second optically anisotropic layer is lowered, which adversely affects image display.
　本発明は、正面コントラスト、コントラストムラ、偏光子の密着性のすべての観点の品質を満たすために優れていることは明白である。 It is clear that the present invention is excellent in satisfying the quality of all aspects of front contrast, contrast unevenness, and polarizer adhesion.
　１　溶解釜
　３、６、１２、１５　濾過器
　４、１３　ストックタンク
　５、１４　送液ポンプ
　８、１６　導管
　１０　紫外線吸収剤仕込釜
　２０　合流管
　２１　混合機
　３０　ダイ
　３１　金属支持体
　３２　ウェブ
　３３　剥離位置
　３４　テンター装置
　３５　ロール乾燥装置
　４１　粒子仕込釜
　４２　ストックタンク
　４３　ポンプ
　４４　濾過器
　５０　液晶表示装置
　６０Ａ、６０Ｂ　偏光板
　６１Ａ、６１Ｂ　偏光板保護フィルム
　６２Ａ　第１偏光子
　６２Ｂ　第２偏光子
　６３Ａ　第２光学異方性層
　６４Ａ　接着層
　６５Ａ　第１光学異方性層
　６５Ｂ　等方性フィルム
　６６Ａ、６６Ｂ　粘着層
　７０　液晶セル
　８０　バックライト
　ａ　吸収軸
　ｂ　面内遅相軸
　ｃ　ラビング軸 DESCRIPTION OF SYMBOLS 1 Melting pot 3, 6, 12, 15 Filter 4, 13 Stock tank 5, 14 Liquid feed pump 8, 16 Conduit 10 Ultraviolet absorber charging pot 20 Merge pipe 21 Mixer 30 Die 31 Metal support 32 Web 33 Peeling position 34 Tenter Device 35 Roll Dryer 41 Particle Charger 42 Stock Tank 43 Pump 44 Filter 50 Liquid Crystal Display Device 60A, 60B Polarizer 61A, 61B Polarizer Protective Film 62A First Polarizer 62B Second Polarizer 63A Second Optical Diffuser Isotropic layer 64A Adhesive layer 65A First optical anisotropic layer 65B Isotropic film 66A, 66B Adhesive layer 70 Liquid crystal cell 80 Backlight a Absorption axis b In-plane slow axis c Rubbing axis

Claims (2)

  1. 　少なくとも第１光学異方性層及び第２光学異方性層を有する偏光板であって、粘着層／第１光学異方性層／接着層／第２光学異方性層／偏光子の順で構成され、かつ下記要件（ｉ）～（iii）を満たすことを特徴とする偏光板。
    （ｉ）第１光学異方性層が、アクリル樹脂含有フィルムであって、面内のリターデーションＲｏ（１）が－４０～２０ｎｍの範囲内であり、かつ、厚さ方向のリターデーションＲｔ（１）が－４００～－８０ｎｍの範囲内である。
    （ii）第２光学異方性層が、セルロースエステル樹脂で構成されたフィルムであって、屈折率がｎｘ＞ｎｙ＞ｎｚの関係にあり、面内のリターデーションＲｏ（２）が２０～１５０ｎｍの範囲内であり、かつ、厚さ方向のリターデーションＲｔ（２）が１００～３００ｎｍの範囲内である。
    〔但し、第１光学異方性層及び第２光学異方性層の屈折率は、以下のｎｘ、ｎｙ、ｎｚで定義され、
    Ｒｏ（１）＝（ｎｘ－ｎｙ）×ｄ
    Ｒｔ（１）＝（（ｎｘ＋ｎｙ）／２－ｎｚ）×ｄ、
    及び
    Ｒｏ（２）＝（ｎｘ－ｎｙ）×ｄ
    Ｒｔ（２）＝（（ｎｘ＋ｎｙ）／２－ｎｚ）×ｄ
    で示される。
    （iii）第１光学異方性層を構成するフィルムの透湿度が２０～６００ｇ／ｍ２・２４ｈの範囲内であり、第２光学異方性層を構成するフィルムの透湿度が６００～１５００ｇ／ｍ２・２４ｈである。
    （式中、ｎｘは光学異方性層の面内の幅手方向の屈折率を、ｎｙは光学異方性層の面内で製膜又は搬送方向でありｎｘと面内で直交する方向の屈折率を、ｎｚは光学異方性層の厚さ方向の屈折率を、ｄは光学異方性層の厚さ（ｎｍ）をそれぞれ表す。屈折率の測定波長は５９０ｎｍである。）〕     A polarizing plate having at least a first optical anisotropic layer and a second optical anisotropic layer, in the order of adhesive layer / first optical anisotropic layer / adhesive layer / second optical anisotropic layer / polarizer And a polarizing plate characterized by satisfying the following requirements (i) to (iii):
    (I) The first optically anisotropic layer is an acrylic resin-containing film, the in-plane retardation Ro (1) is in the range of −40 to 20 nm, and the thickness direction retardation Rt ( 1) is in the range of −400 to −80 nm.
    (Ii) The second optically anisotropic layer is a film composed of a cellulose ester resin and has a refractive index of nx>ny> nz, and an in-plane retardation Ro (2) of 20 to 150 nm. And retardation Rt (2) in the thickness direction is in the range of 100 to 300 nm.
    [However, the refractive indexes of the first optical anisotropic layer and the second optical anisotropic layer are defined by the following nx, ny, and nz,
    Ro (1) = (nx−ny) × d
    Rt (1) = ((nx + ny) / 2−nz) × d,
    And Ro (2) = (nx−ny) × d
    Rt (2) = ((nx + ny) / 2−nz) × d
    Indicated by
    (Iii) The moisture permeability of the film constituting the first optical anisotropic layer is in the range of 20 to 600 g / m 2 · 24 h, and the moisture permeability of the film constituting the second optical anisotropic layer is 600 to 1500 g. / M 2 · 24h.
    (Where nx is the refractive index in the width direction in the plane of the optically anisotropic layer, ny is the film forming or conveying direction in the plane of the optically anisotropic layer, and is in the direction perpendicular to nx in the plane) The refractive index, nz represents the refractive index in the thickness direction of the optically anisotropic layer, d represents the thickness (nm) of the optically anisotropic layer, and the measurement wavelength of the refractive index is 590 nm.)]
  2. 　請求項１に記載の偏光板を用いたことを特徴とする液晶表示装置。 A liquid crystal display device using the polarizing plate according to claim 1.
PCT/JP2009/069774 2008-12-10 2009-11-24 Polarizing plate and liquid crystal display device using same WO2010067700A1 (en)

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