JP2012123291A - Polarizing plate and liquid-crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polarizing plate and liquid-crystal display having a cellulose acylate-based protective film which is a thin film with low haze and has sufficient ultraviolet absorbability to prevent panel deterioration.SOLUTION: The polarizing plate is formed by sandwiching a polarizer between a protective film A and a protective film B. The protective film A is a cellulose acylate film which: at least contains cellulose acylate with the total degree of acyl substitution 2.0-2.5 and an ultraviolet absorber represented by the general formula (Ab) with the maximum absorption wavelength 380 nm or less; and has a phase difference with in-plane retardation Ro in the range of 30-90 nm and thickness retardation Rth in the range of 70-300 nm.

Description

  The present invention relates to a polarizing plate and a liquid crystal display device, and more specifically, a cellulose acylate having a specific total acyl substitution degree, and a polarized light having a cellulose acylate-based protective film containing a specific ultraviolet absorber and having a phase difference The present invention relates to a plate and a liquid crystal display device.

  Conventionally, liquid crystal display devices have been used in desktop calculators, electronic timepieces, and the like, but their use has been rapidly expanding in recent years. That is, liquid crystal display devices have been used from mobile devices such as mobile phones to large televisions regardless of screen size.

  A polarizing plate widely used in a liquid crystal display device is represented by a triacetyl cellulose film via a liquid adhesive on both sides of a polarizer in which a dichroic dye is adsorbed and oriented on a polyvinyl alcohol resin film. It is manufactured with the structure which laminated | stacked the cellulose acylate type | system | group protective film. In this state, or if necessary, in a form in which various optical layers such as a retardation film and an optical compensation film having optical properties are bonded via an adhesive or an adhesive, and bonded to an image display element such as a liquid crystal cell. Used.

  In recent years, liquid crystal display devices for mobile use such as mobile phones are becoming thinner and slimmer from the viewpoint of design and portability. As a matter of course, there is a demand for further reduction in thickness and weight of the polarizing plate used there.

  On the other hand, an ultraviolet absorber is used for the protective film of the polarizing plate for the purpose of protecting the liquid crystal panel from ultraviolet rays. In particular, the ultraviolet absorber has been added to the protective film on the surface of the viewing side polarizing plate of the liquid crystal panel and the protective film on the surface of the backlight side polarizing plate.

  However, if the surface-side protective film of the polarizing plate is simply made thinner, the content of the ultraviolet absorber added to protect the panel from ultraviolet rays decreases, and the durability of the panel, particularly the contrast, deteriorates. Therefore, when the thin film was formed by including an ultraviolet absorber in an amount capable of having sufficient UV absorption performance even in a thin film, an increase in haze due to bleeding out of the ultraviolet absorber was observed. Since the protective film on the surface side was exposed to the outside air and heat, the tendency was remarkable.

  Although the technique of the ultraviolet absorber with which precipitation of the ultraviolet absorber accompanying the said thin film formation or the bleed-out by high temperature and high humidity does not produce is disclosed (for example, refer patent document 1), this ultraviolet absorber is contained. It has been found that the cellulose acylate protective film having a reduced thickness still has the above problems.

  Therefore, in the field of mobile-use polarizing plates, which are designed to be thinner and lighter by reducing the number of components, a cellulose acylate film-based protective film with a thin film, low haze, and sufficient UV absorption performance to prevent panel deterioration There is a demand for the development of polarizing plates having the following characteristics.

JP 2009-96971 A

  Accordingly, an object of the present invention is to provide a polarizing plate and a liquid crystal display device having a cellulose acylate protective film having a thin film, low haze, and sufficient ultraviolet absorption performance for preventing panel deterioration.

  The above object of the present invention is achieved by the following configurations.

  1. In the polarizing plate in which both surfaces of the polarizer are sandwiched between the protective film A and the protective film B, the protective film A has a cellulose acylate with a total acyl substitution degree of 2.0 to 2.5 and a maximum absorption wavelength below 380 nm. It is a cellulose acylate film containing at least an ultraviolet absorber represented by the general formula (Ab), having an in-plane retardation Ro of 30 to 90 nm and a retardation Rth in the thickness direction of 70 to 300 nm. A polarizing plate characterized by that.

(R _{1 to} R ₆ represent a hydrogen atom, a halogen atom, and a substituent, and X and Y are substituents bonded to the benzene ring by a hydrogen atom, a halogen atom, or a hetero atom, and either X or Y Is a substituent bonded to the benzene ring by a heteroatom)
2. 2. The polarizing plate according to 1 above, wherein the protective film A and the protective film B have a width of 1.9 to 2.5 m and a film thickness of 10 to 65 μm.

  3. 3. The polarizing plate as described in 1 or 2 above, wherein the protective film A contains a retardation adjusting agent and a plasticizer.

  4). The polarizing plate according to any one of 1 to 3, wherein the protective film A is stretched.

  5). 5. The polarizing plate according to any one of 1 to 4, wherein the protective film B is a cellulose acylate film containing no ultraviolet absorber.

  6). It is a liquid crystal display device which has a polarizing plate of any one of said 1-5, Comprising: The said protective film A is bonded by the liquid crystal cell surface, The liquid crystal display device characterized by the above-mentioned.

  ADVANTAGE OF THE INVENTION According to this invention, the polarizing plate and liquid crystal display device which have a cellulose acylate type | system | group protective film with a low haze, a low haze, and sufficient ultraviolet absorption performance for prevention of panel deterioration can be provided.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail, but the present invention is not limited thereto.

  As a result of intensive studies in view of the above problems, the present inventors have found that the protective film A has a total acyl substitution degree of 2.0 to 2 in the polarizing plate in which both surfaces of the polarizer are sandwiched between the protective film A and the protective film B. 5 and a UV absorber represented by the above general formula (Ab) having a maximum absorption wavelength at 380 nm or less, an in-plane retardation Ro of 30 to 90 nm, and a thickness direction retardation Rth of 70. It has been found that a polarizing plate characterized by being a cellulose acylate film having a retardation in a range of ˜300 nm can provide a polarizing plate having a thin film with low haze and sufficient ultraviolet absorption performance to prevent panel deterioration. It is a thing.

  The ultraviolet absorber represented by the general formula (Ab) has a certain degree of compatibility with triacetylcellulose having a total acyl group substitution degree of 2.7 to 3.0, which is used as a conventional polarizing plate protective film. Although excellent, it was difficult to achieve both a bleed-out property by thinning and maintaining a sufficient UV absorption ability.

  In the process of studying the combination of the ultraviolet absorber represented by the general formula (Ab) and various cellulose acylates, the present inventors have obtained a cellulose acylate having a total acyl substitution degree of 2.0 to 2.5. It has been found that when combined, the compatibility is extremely excellent, and an amount capable of imparting sufficient ultraviolet absorbing performance can be contained even when the film is thinned.

  A cellulose acylate film using cellulose acylate having a total acyl substitution degree of 2.0 to 2.5 has many hydrophilic groups due to a low total acyl substitution degree. It is estimated that the compatibility with the absorbent is a significant improvement. It was also found that the cellulose acylate film using the cellulose acylate has a better influence on the compatibility when the cellulose molecules are stretched by the stretching treatment. By this stretching treatment, the cellulose acylate film has a retardation, and can be used as an optical compensation film.

  In addition, since the cellulose acylate film using the cellulose acylate is inherently rich in hydrophilicity, when used as a polarizing plate protective film, it is more than used on the surface side where the heat of the outside air or the backlight directly affects. From the viewpoint of imparting an optical compensation function to the polarizing plate, use as a protective film A having a phase difference is a preferable embodiment of the present invention.

  Furthermore, in the case of this embodiment, the protective film A according to the present invention, which is bonded to the opposite surface across the polarizer, does not need to contain an ultraviolet absorber, and is influenced by the outside air and heat. It is preferable not to contain an ultraviolet absorber from the viewpoint of being easy to receive and preventing bleeding out and haze rise, and also from the viewpoint of thinning.

  The present invention will be described in detail below.

<Ultraviolet absorber represented by general formula (Ab)>
The protective film A according to the present invention is characterized by containing an ultraviolet absorber represented by the following general formula (Ab), and the ultraviolet absorber has a total acyl substitution degree of 2.0 to 2.5. Excellent compatibility with rate.

(R _{1 to} R ₆ represent a hydrogen atom, a halogen atom, and a substituent, and X and Y are substituents bonded to the benzene ring by a hydrogen atom, a halogen atom, or a hetero atom, and either X or Y Is a substituent bonded to the benzene ring by a heteroatom)
Examples of the substituent include an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, an alkoxy group, an aryloxy group, a heterocyclic oxy group, an acyloxy group, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoyl group, and an amino group. Group, alkylamino group, anilino group, acylamino group, hydroxyl group, cyano group, nitro group, sulfonamido group, sulfamoylamino group, sulfonyl group, sulfamoyl group, sulfonylamino group, ureido group, imide group, silyl group, An alkylthio group etc. are mentioned.

  Moreover, it is preferable that the number of heteroatoms of either X or Y is 2 or more.

  The compound of the general formula (Ab) preferably has 3 or more hydroxyl groups. Further, it is preferable that the substituent does not contain halogen.

  Specific examples of the ultraviolet absorber represented by the general formula (Ab) are shown below, but the present invention is not limited thereto.

  The content of the ultraviolet absorbent according to the present invention in the protective film A is preferably added at a rate of 0.1 to 40% by mass, and preferably 0.5 to 10% by mass.

<Cellulose acylate>
The protective film A according to the present invention is a cellulose acylate film, which is excellent in compatibility with the ultraviolet absorber represented by the general formula (Ab), has a high retardation, and has a high retardation. A film made of cellulose acylate having a total acyl substitution degree of 2.0 to 2.5 is used from the viewpoint of being able to reduce the thickness even if it is a film. Preferably, the cellulose acylate is diacetyl cellulose.

  The total acyl substitution degree can be measured in accordance with ASTM D-817-91, and the preferred total acyl substitution degree is 2.2 to 2.45.

  When the total acyl substitution degree of cellulose acylate is less than 2.0, deterioration of film surface quality due to an increase in dope viscosity, haze increase due to an increase in stretching tension, and the like may occur. Further, when the total acyl substitution degree is larger than 2.5, it is difficult to obtain a necessary phase difference.

  The number average molecular weight (Mn) of the cellulose acylate is preferable because the mechanical strength of the film from which a range of 30000 to 300000 is obtained is strong. Furthermore, the thing of 50000-200000 is used preferably.

  The value of the ratio Mw / Mn of the weight average molecular weight (Mw) and the number average molecular weight (Mn) of the cellulose acylate is preferably 1.4 to 3.0.

  The number average molecular weight (Mn) and weight average molecular weight (Mw) of the cellulose acylate were measured using gel permeation chromatography (GPC).

  The measurement conditions are as follows.

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 (manufactured by GL Sciences)
Pump: L6000 (manufactured by Hitachi, Ltd.)
Flow rate: 1.0ml / min
Calibration curve: Standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) Mw = 100000 to 500 calibration curves with 13 samples were used. Thirteen samples are used at approximately equal intervals.

  The cellulose acylate used in the present invention can be synthesized by a known method.

  Cellulose as a raw material for cellulose acylate is not particularly limited, and examples thereof include cotton linter, wood pulp (derived from conifers and hardwoods), kenaf and the like. Moreover, the cellulose acylate obtained from them can be mixed and used at an arbitrary ratio.

  The cellulose acylate according to the present invention can be produced by a known method. Specifically, it can be synthesized with reference to the method described in JP-A-10-45804.

  Examples of commercially available products include Daicel Corporation L20, L30, L40, and L50, and Eastman Chemical's Ca398-3, Ca398-6, Ca398-10, Ca398-30, and Ca394-60S.

  Although the protective film B which concerns on this invention is not specifically limited, It is preferable that it is a cellulose acylate film, and a total acyl substitution degree is 2.7-3.0 from a viewpoint of durability to external air and a heat | fever. It is preferable that the cellulose acylate film is a triacetyl cellulose film.

  Hereinafter, the cellulose acylate film according to the present invention means the protective film A and the protective film B according to the present invention.

<Other additives>
The cellulose acylate film according to the present invention includes, as additives other than the ultraviolet absorber according to the present invention, a retardation adjusting agent, a plasticizer, a deterioration (oxidation) inhibitor, a peeling aid, a surfactant, a dye, and fine particles. Etc. are preferably contained.

  The protective film A according to the present invention preferably contains a retardation adjusting agent, a plasticizer imparting heat and humidity resistance, and a deterioration (oxidation) inhibitor, and the protective film B according to the present invention contains the above additives. It is preferable to contain as needed.

  In the present invention, additives other than fine particles may be added when preparing the cellulose acylate solution, or may be added when preparing the fine particle dispersion.

<Retardation adjuster>
The retardation adjusting agent according to the present invention refers to both a retardation reducing agent and a retardation developing agent.

(Retardation reducing agent)
The high molecular weight additive used as a retardation reducing agent for the cellulose acylate film according to the present invention has a repeating unit in the compound, and preferably has a number average molecular weight of 700 to 10,000. The high molecular weight additive also has a function of increasing the volatilization rate of the solvent and reducing the amount of residual solvent in the solution casting method. Furthermore, it exhibits useful effects from the viewpoint of film modification such as improvement in mechanical properties, imparting flexibility, imparting water absorption resistance, and reducing moisture permeability.

  Here, the number average molecular weight of the high molecular weight additive in the present invention is more preferably a number average molecular weight of 700 to 8000, still more preferably a number average molecular weight of 700 to 5000, and particularly preferably a number average molecular weight of 1000 to 5000. is there.

  Hereinafter, although the high molecular weight additive used for this invention is demonstrated in detail, giving the specific example, it cannot be overemphasized that the high molecular weight additive used by this invention is not necessarily limited to these.

  The polymer additive is selected from polyester polymers, styrene polymers, acrylic polymers and copolymers thereof, and aliphatic polyesters, acrylic polymers and styrene polymers are preferred. Moreover, it is preferable that at least one polymer having negative intrinsic birefringence, such as a styrene polymer and an acrylic polymer, is included.

  The polyester polymer is a reaction of an aliphatic dicarboxylic acid having 2 to 20 carbon atoms with at least one diol selected from an aliphatic diol having 2 to 12 carbon atoms and an alkyl ether diol having 4 to 20 carbon atoms. The both ends of the reaction product may be left as the reaction product, or a so-called end-capping may be carried out by further reacting monocarboxylic acids, monoalcohols or phenols. It is effective in terms of storage stability that the end capping is performed in particular so as not to contain free carboxylic acids. The dicarboxylic acid used in the polyester polymer according to the present invention is preferably an aliphatic dicarboxylic acid residue having 4 to 20 carbon atoms or an aromatic dicarboxylic acid residue having 8 to 20 carbon atoms.

  Examples of the aliphatic dicarboxylic acid having 2 to 20 carbon atoms preferably used in the present invention include oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, pimelic acid, suberic acid, and azelaic acid. , Sebacic acid, dodecanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid.

  Among these, preferable aliphatic dicarboxylic acids are malonic acid, succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, azelaic acid, and 1,4-cyclohexanedicarboxylic acid. Particularly preferably, the aliphatic dicarboxylic acid component is succinic acid, glutaric acid, or adipic acid.

  The diol utilized for the high molecular weight additive is selected from, for example, an aliphatic diol having 2 to 20 carbon atoms and an alkyl ether diol having 4 to 20 carbon atoms.

  Examples of the aliphatic diol having 2 to 20 carbon atoms include alkyl diols and alicyclic diols, such as ethane diol, 1,2-propanediol, 1,3-propanediol, and 1,2-butane. Diol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol) ), 2,2-diethyl-1,3-propanediol (3,3-dimethylolpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolheptane), 3 -Methyl-1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl 1,3-hexanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-octadecanediol, and the like. Used as a mixture of two or more.

  Preferred aliphatic diols include ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1 , 4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, particularly preferred Is ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6- Hexanediol, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol.

  Preferred examples of the alkyl ether diol having 4 to 20 carbon atoms include polytetramethylene ether glycol, polyethylene ether glycol and polypropylene ether glycol, and combinations thereof. The average degree of polymerization is not particularly limited, but is preferably 2 to 20, more preferably 2 to 10, further 2 to 5, and particularly preferably 2 to 4. As examples of these, commercially useful polyether glycols typically include Carbowax, Pluronics and Niax resins.

  In the present invention, a high molecular weight additive whose end is sealed with an alkyl group or an aromatic group is particularly preferable. This is because the terminal is protected with a hydrophobic functional group, which is effective against deterioration with time at high temperature and high humidity, and is due to the role of delaying hydrolysis of the ester group.

  It is preferable to protect with a monoalcohol residue or a monocarboxylic acid residue so that both ends of the polyester additive used in the present invention do not become a carboxylic acid or an OH group.

  In this case, the monoalcohol is preferably a substituted or unsubstituted monoalcohol having 1 to 30 carbon atoms, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, isopentanol, hexanol, isohexanol, cyclohexyl alcohol. , Octanol, isooctanol, 2-ethylhexyl alcohol, nonyl alcohol, isononyl alcohol, tert-nonyl alcohol, decanol, dodecanol, dodecahexanol, aliphatic alcohol such as dodecaoctanol, allyl alcohol, oleyl alcohol, benzyl alcohol, 3-phenyl Examples thereof include substituted alcohols such as propanol.

  End-capping alcohols that can be preferably used are methanol, ethanol, propanol, isopropanol, butanol, isobutanol, isopentanol, hexanol, isohexanol, cyclohexyl alcohol, isooctanol, 2-ethylhexyl alcohol, isononyl alcohol, oleyl alcohol Benzyl alcohol, in particular methanol, ethanol, propanol, isobutanol, cyclohexyl alcohol, 2-ethylhexyl alcohol, isononyl alcohol, benzyl alcohol.

  Moreover, when sealing with a monocarboxylic acid residue, the monocarboxylic acid used as a monocarboxylic acid residue is preferably a substituted or unsubstituted monocarboxylic acid having 1 to 30 carbon atoms. These may be aliphatic monocarboxylic acids or aromatic ring-containing carboxylic acids. Preferred aliphatic monocarboxylic acids are described, for example, acetic acid, propionic acid, butanoic acid, caprylic acid, caproic acid, decanoic acid, dodecanoic acid, stearic acid, oleic acid, and examples of the aromatic ring-containing monocarboxylic acid include Benzoic acid, p-tert-butylbenzoic acid, p-tert-amylbenzoic acid, orthotoluic acid, metatoluic acid, p-toluic acid, dimethylbenzoic acid, ethylbenzoic acid, normal propylbenzoic acid, aminobenzoic acid, acetoxybenzoic acid, etc. Yes, these can be used alone or in combination of two or more.

  The high molecular weight additive used in the present invention is synthesized by hot melt shrinkage by a polyesterification reaction or a transesterification reaction between the dicarboxylic acid and a diol and / or a monocarboxylic acid or monoalcohol for end-capping. The compound can be easily synthesized by any of the methods of interfacial condensation between acid chlorides of these acids and glycols. These polyester-based additives are described in detail in Koichi Murai, “Additives, Theory and Application” (Kokaibo Co., Ltd., first edition published on March 1, 1973). In addition, Japanese Patent Laid-Open Nos. 05-155809, 05-155810, Japanese Patent Laid-Open Nos. 05-97073, 2006-259494, 07-330670, 2006-342227, 2007-003679. The materials described in each publication can also be used.

  The styrenic polymer is preferably a structural unit obtained from an aromatic vinyl monomer represented by the general formula (1).

In the formula, each of R ^{101 to} R ¹⁰⁴ independently represents a substituted or unsubstituted carbon atom which may have a linking group containing a hydrogen atom, a halogen atom, an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom. R ¹⁰⁴ represents a hydrocarbon group of 1 to 30 or a polar group, and R ¹⁰⁴ may be the same atom or group or different atoms or groups, and may be bonded to each other to form a carbocyclic or heterocyclic ring ( These carbocycles and heterocycles may form a monocyclic structure, or other rings may be condensed to form a polycyclic structure.

  Specific examples of the aromatic vinyl monomer include styrene; alkyl-substituted styrenes such as α-methylstyrene, β-methylstyrene, and p-methylstyrene; halogen-substituted styrenes such as 4-chlorostyrene and 4-bromostyrene. Hydroxystyrenes such as p-hydroxystyrene, α-methyl-p-hydroxystyrene, 2-methyl-4-hydroxystyrene, 3,4-dihydroxystyrene; vinyl benzyl alcohols; p-methoxystyrene, p-tert Alkoxy-substituted styrenes such as butoxystyrene and m-tert-butoxystyrene; vinyl benzoic acids such as 3-vinylbenzoic acid and 4-vinylbenzoic acid; vinyl such as methyl-4-vinylbenzoate and ethyl-4-vinylbenzoate Benzoic acid esters; 4-vinyl vinyl 4-acetoxystyrene; amidostyrenes such as 2-butylamidostyrene, 4-methylamidostyrene, p-sulfonamidostyrene; 3-aminostyrene, 4-aminostyrene, 2-isopropenylaniline, vinylbenzyldimethyl Aminostyrenes such as amines; nitrostyrenes such as 3-nitrostyrene and 4-nitrostyrene; cyanostyrenes such as 3-cyanostyrene and 4-cyanostyrene; vinylphenylacetonitrile; arylstyrenes such as phenylstyrene, indene The present invention is not limited to these specific examples. Two or more of these monomers may be used as a copolymerization component. Of these, styrene and α-methylstyrene are preferred because they are easily available industrially and are inexpensive.

  The acrylic polymer is preferably a structural unit obtained from an acrylate ester monomer represented by the general formula (2).

In the formula, each of R ^{105 to} R ¹⁰⁸ independently represents a substituted or unsubstituted carbon atom which may have a linking group containing a hydrogen atom, a halogen atom, an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom. This represents a hydrocarbon group having 1 to 30 or a polar group.

  Examples of the acrylate monomer include, for example, methyl acrylate, ethyl acrylate, propyl acrylate (i-, n-), butyl acrylate (n-, i-, s-, tert-). , Pentyl acrylate (n-, i-, s-), hexyl acrylate (n-, i-), heptyl acrylate (n-, i-), octyl acrylate (n-, i-), acrylic acid Nonyl (n-, i-), myristyl acrylate (n-, i-), acrylic acid (2-ethylhexyl), acrylic acid (ε-caprolactone), acrylic acid (2-hydroxyethyl), acrylic acid (2- Hydroxypropyl), acrylic acid (3-hydroxypropyl), acrylic acid (4-hydroxybutyl), acrylic acid (2-hydroxybutyl), acrylic acid (2-methoxyethyl) Acrylic acid (2-ethoxyethyl) phenyl acrylate, phenyl methacrylate, acrylic acid (2 or 4-chlorophenyl), methacrylic acid (2 or 4-chlorophenyl), acrylic acid (2 or 3 or 4-ethoxycarbonylphenyl), Methacrylic acid (2 or 3 or 4-ethoxycarbonylphenyl), acrylic acid (o or m or p-tolyl), methacrylic acid (o or m or p-tolyl), benzyl acrylate, benzyl methacrylate, phenethyl acrylate, Phenethyl methacrylate, acrylic acid (2-naphthyl), cyclohexyl acrylate, cyclohexyl methacrylate, acrylic acid (4-methylcyclohexyl), methacrylic acid (4-methylcyclohexyl), acrylic acid (4-ethylcyclohexyl), Examples thereof include tacrylic acid (4-ethylcyclohexyl) and the like, or those obtained by replacing the acrylic ester with a methacrylic ester, but the present invention is not limited to these specific examples. Two or more of these monomers may be used as a copolymerization component. Of these, methyl acrylate, ethyl acrylate, propyl acrylate (i-, n-), butyl acrylate (n-, i-, s-, tert-), pentyl acrylate (n-, i-, s-), hexyl acrylate (n-, i-), or those obtained by replacing the acrylate ester with a methacrylate ester are preferred.

  The copolymer contains at least one structural unit obtained from an aromatic vinyl monomer represented by the general formula (1) and an acrylate ester monomer represented by the general formula (2). Is preferred.

In the formula, each of R ^{101 to} R ¹⁰⁴ independently represents a substituted or unsubstituted carbon atom which may have a linking group containing a hydrogen atom, a halogen atom, an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom. R ¹⁰⁴ represents a hydrocarbon group of 1 to 30 or a polar group, and R ¹⁰⁴ may be the same atom or group or different atoms or groups, and may be bonded to each other to form a carbocyclic or heterocyclic ring ( These carbocycles and heterocycles may form a monocyclic structure, or other rings may be condensed to form a polycyclic structure.

In the formula, R ^{105 to} R ¹⁰⁸ each independently have a linking group containing a hydrogen atom, a halogen atom, an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom, and the number of substituted or unsubstituted carbon atoms 1-30 hydrocarbon groups or a polar group is represented. Further, the structure other than the above constituting the copolymer composition is preferably excellent in copolymerizability with the monomer, and examples thereof include maleic anhydride, citraconic anhydride, cis-1-cyclohexene-1 , 2-dicarboxylic anhydride, 3-methyl-cis-1-cyclohexene-1,2-dicarboxylic anhydride, 4-methyl-cis-1-cyclohexene-1,2-dicarboxylic anhydride and the like, acrylonitrile, Nitrile group-containing radical polymerizable monomers such as methacrylonitrile; amide bond-containing radical polymerizable monomers such as acrylamide, methacrylamide, trifluoromethanesulfonylaminoethyl (meth) acrylate; fatty acid vinyls such as vinyl acetate; Chlorine-containing radical polymerizable monomers such as vinyl and vinylidene chloride; 1,3-butadiene; Isoprene, 1,4-dimethyl butadiene and the like can be mentioned conjugated diolefins but the present invention is not limited thereto. Of these, styrene-acrylic acid copolymers, styrene-maleic anhydride copolymers, and styrene-acrylonitrile copolymers are particularly preferred.

(Low molecular weight additive)
Examples of the low molecular weight additive include the following. These may be solid or oily. That is, the melting point and boiling point are not particularly limited. For example, mixing of an ultraviolet absorbing material at 20 ° C. or lower and 20 ° C. or higher, and a mixture of deterioration preventing agents are also possible. Furthermore, infrared absorbing dyes are described, for example, in JP-A No. 2001-194522. Moreover, the addition time may be added at any time in the cellulose acylate solution (dope) preparation step, but it may be added by adding a preparation step to the final preparation step of the dope preparation step. Furthermore, the amount of each material added is not particularly limited as long as the function is manifested.

  Although it does not specifically limit as a low molecular weight additive, The compound represented by General formula (3)-(7) described below is mentioned.

(In the formula, R ¹ represents an alkyl group or an aryl group, and R ² and R ³ each independently represents a hydrogen atom, an alkyl group, or an aryl group. The number of carbon atoms of R ¹ , R ^2, and R ³ is The sum is 10 or more.)

(In the formula, R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group. The total number of carbon atoms of R ⁴ and R ⁵ is 10 or more.)
In General Formula (3), R ¹ represents an alkyl group or an aryl group, and R ² and R ³ each independently represent a hydrogen atom, an alkyl group, or an aryl group. Moreover, it is especially preferable that the total number of carbon atoms of R ¹ , R ² and R ³ is 10 or more. In the general formula (4), R ⁴ and R ⁵ each independently represents an alkyl group or an aryl group. The total number of carbon atoms of R ⁴ and R ⁵ is 10 or more, and each of the alkyl group and aryl group may have a substituent. As the substituent, a fluorine atom, an alkyl group, an aryl group, an alkoxy group, a sulfone group, and a sulfonamide group are preferable, and an alkyl group, an aryl group, an alkoxy group, a sulfone group, and a sulfonamide group are particularly preferable. The alkyl group may be linear, branched, or cyclic, and preferably has 1 to 25 carbon atoms, more preferably 6 to 25, and 6 to 20 ( For example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert-butyl group, amyl group, isoamyl group, tert-amyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, bicyclooctyl Group, nonyl group, adamantyl group, decyl group, tert-octyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, didecyl group). As the aryl group, those having 6 to 30 carbon atoms are preferable, and those having 6 to 24 carbon atoms (for example, phenyl group, biphenyl group, terphenyl group, naphthyl group, binaphthyl group, triphenylphenyl group) are particularly preferable. Although the preferable example of a compound represented by General formula (3) or General formula (4) is shown below, this invention is not limited to these specific examples.

  The compound represented by the general formula (3) or the general formula (4) can be prepared by the following method.

  The compound of the general formula (3) can be obtained by a condensation reaction between a sulfonyl chloride derivative and an amine derivative. The compound of the general formula (4) can be obtained by oxidation reaction of sulfide or Friedel-Crafts reaction of aromatic compound and sulfonic acid chloride.

  Next, the compound represented by the general formula (5) will be described in detail.

In the general formula (5), R ¹¹ represents an aryl group. R ¹² and R ¹³ each independently represents an alkyl group or an aryl group, and at least one of them is an aryl group. When R ¹² is an aryl group, R ¹³ may be an alkyl group or an aryl group, but is more preferably an alkyl group. Here, the alkyl group may be linear, branched or cyclic, and preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and 1 to 12 carbon atoms. Is most preferred. The aryl group preferably has 6 to 36 carbon atoms, and more preferably 6 to 24 carbon atoms.

  Next, the compound represented by the general formula (6) will be described in detail.

In the general formula (6), R ²¹ , R ²² and R ²³ each independently represents an alkyl group. Here, the alkyl group may be linear, branched or cyclic. R ²¹ is preferably a cyclic alkyl group, and more preferably at least one of R ²² and R ²³ is a cyclic alkyl group. The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and most preferably 1 to 12 carbon atoms. As the cyclic alkyl group, a cyclohexyl group is particularly preferable.

  The alkyl group and aryl group in the general formulas (5) and (6) may each have a substituent. Substituents include halogen atoms (for example, chlorine, bromine, fluorine and iodine), alkyl groups, aryl groups, alkoxy groups, aryloxy groups, acyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, acyloxy groups, sulfonylamino groups, A hydroxy group, a cyano group, an amino group and an acylamino group are preferred, more preferably a halogen atom, an alkyl group, an aryl group, an alkoxy group, an aryloxy group, a sulfonylamino group and an acylamino group, and particularly preferably an alkyl group and an aryl group. A sulfonylamino group and an acylamino group.

  Next, although the preferable example of a compound represented by General formula (5) and (6) is shown below, this invention is not limited to these specific examples.

  Next, the compound represented by the general formula (7) will be described.

In the general formula (7), R ³¹ , R ³² , R ³³ and R ³⁴ each represent a hydrogen atom, a substituted or unsubstituted aliphatic group, or a substituted or unsubstituted aromatic group, and an aliphatic group Is preferred. The aliphatic group may be linear, branched or cyclic, and more preferably cyclic. Examples of the substituent that the aliphatic group and the aromatic group may have include the substituent T described later, but an unsubstituted one is preferable.

X ³¹ , X ³² , X ³³ and X ³⁴ are each a single bond, —CO— and NR ³⁵ — (R ³⁵ represents a substituted or unsubstituted aliphatic group, or a substituted or unsubstituted aromatic group; It represents a divalent linking group formed from one or more groups selected from the group consisting of unsubstituted and / or aliphatic groups. The combination of X ³¹ , X ³² , X ³³ and X ³⁴ is not particularly limited, but is more preferably selected from —CO— and —NR ³⁵ —. a, b, c and d are integers of 0 or more, preferably 0 or 1, a + b + c + d is 2 or more, preferably 2 to 8, more preferably 2 to 6, still more preferably 2-4. Z ³¹ represents an (a + b + c + d) -valent organic group (excluding a cyclic group). Valence of Z ³¹ is preferably 2 to 8, more preferably 2 to 6, preferably 2 to 4 further 2 or 3 being most preferred. An organic group refers to a group composed of an organic compound.

  The general formula (7) is preferably a compound represented by the following general formula (7-1).

Formula (7-1)
R ³¹¹ -X ³¹¹ -Z ³¹¹ -X ³¹² -R ³¹²
In the general formula (7-1), R ³¹¹ and R ³¹² each represent a substituted or unsubstituted aliphatic group or a substituted or unsubstituted aromatic group, and an aliphatic group is preferable. The aliphatic group may be linear, branched or cyclic, and more preferably cyclic. Examples of the substituent that the aliphatic group and the aromatic group may have include the substituent T described later, but an unsubstituted one is preferable. X ³¹¹ and X ³¹² each independently represent —CONR ³¹³ — or NR ³¹⁴ CO—, and R ³¹³ and R ^{314 each} represents a substituted or unsubstituted aliphatic group, or a substituted or unsubstituted aromatic group. More preferred are unsubstituted and / or aliphatic groups. Z ³¹¹ is —O—, —S—, —SO—, —SO ₂ —, —CO—, —NR ³¹⁵ — (R ³¹⁵ is a substituted or unsubstituted aliphatic group, or a substituted or unsubstituted aromatic group. Represents an unsubstituted group and / or an aliphatic group, and a divalent organic group (excluding a cyclic group) formed from one or more groups selected from an alkylene group and an arylene group. . The combination of Z ³¹¹ is not particularly limited, but is preferably selected from —O—, —S—, —NR ³¹⁵ —, and an alkylene group, and more preferably selected from —O—, —S—, and an alkylene group. Most preferably, it is selected from, -O-, -S- and an alkylene group.

  The general formula (7-1) is preferably a compound represented by the following general formulas (7-2) to (7-4).

In the general formulas (7-2) to (7-4), R ³²¹ , R ³²² , R ³²³ and R ³²⁴ each represents a substituted or unsubstituted aliphatic group or a substituted or unsubstituted aromatic group. An aliphatic group is preferred. The aliphatic group may be linear, branched or cyclic, and more preferably cyclic. Examples of the substituent that the aliphatic group and the aromatic group may have include the substituent T described later, but an unsubstituted one is preferable. Z ³²¹ is —O—, —S—, —SO—, —SO ₂ —, —CO—, —NR ³²⁵ — (R ³²⁵ is a substituted or unsubstituted aliphatic group, or a substituted or unsubstituted aromatic group. Represents an unsubstituted group and / or an aliphatic group, and a divalent linking group formed from one or more groups selected from an alkylene group and an arylene group. The combination of Z ³²¹ is not particularly limited, but is preferably selected from —O—, —S—, —NR ³²⁵ —, and an alkylene group, and more preferably selected from —O—, —S—, and an alkylene group. Most preferably, it is selected from, -O-, -S- and an alkylene group.

  Hereinafter, the substituted or unsubstituted aliphatic group will be described. The aliphatic group may be linear, branched or cyclic, preferably having 1 to 25 carbon atoms, more preferably having 6 to 25 carbon atoms, particularly preferably having 6 to 20 carbon atoms. preferable. Specific examples of the aliphatic group include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, cyclopropyl group, n-butyl group, isobutyl group, tert-butyl group, amyl group, isoamyl group, tert- Amyl group, n-hexyl group, cyclohexyl group, n-heptyl group, n-octyl group, bicyclooctyl group, adamantyl group, n-decyl group, tert-octyl group, dodecyl group, hexadecyl group, octadecyl group, didecyl group, etc. Is mentioned.

  Below, said aromatic group is demonstrated.

  The aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group, and more preferably an aromatic hydrocarbon group. The aromatic hydrocarbon group preferably has 6 to 24 carbon atoms, and more preferably 6 to 12 carbon atoms. Specific examples of the aromatic hydrocarbon group include benzene, naphthalene, anthracene, biphenyl, terphenyl, and the like. As the aromatic hydrocarbon group, benzene, naphthalene, and biphenyl are particularly preferable. As the aromatic heterocyclic group, those containing at least one of an oxygen atom, a nitrogen atom or a sulfur atom are preferable. Specific examples of the heterocyclic ring include, for example, furan, pyrrole, thiophene, imidazole, pyrazole, pyridine, pyrazine, pyridazine, triazole, triazine, indole, indazole, purine, thiazoline, thiadiazole, oxazoline, oxazole, oxadiazole, quinoline, Examples include isoquinoline, phthalazine, naphthyridine, quinoxaline, quinazoline, cinnoline, pteridine, acridine, phenanthroline, phenazine, tetrazole, benzimidazole, benzoxazole, benzthiazole, benzotriazole, and tetrazaindene. As the aromatic heterocyclic group, pyridine, triazine, and quinoline are particularly preferable.

  Moreover, the said substituent T is demonstrated in detail below.

  Examples of the substituent T include alkyl groups (preferably those having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as methyl group, ethyl group, isopropyl group, and tert-butyl group. , N-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2). For example, vinyl group, allyl group, 2-butenyl group, 3-pentenyl group, etc.), alkynyl group (preferably having 2-20 carbon atoms, more preferably 2-12 carbon atoms, particularly preferably 2-8 carbon atoms). Yes, for example, propargyl group, 3-pentynyl group, etc., aryl group (preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, particularly preferably -12, for example, phenyl group, biphenyl group, naphthyl group, etc., amino group (preferably 0-20 carbon atoms, more preferably 0-10, particularly preferably 0-6, for example amino group, methylamino Group, dimethylamino group, diethylamino group, dibenzylamino group, etc.), alkoxy group (preferably having 1 to 20 carbon atoms, more preferably 1 to 12, particularly preferably 1 to 8, such as methoxy group, ethoxy group, Butoxy group, etc.), aryloxy group (preferably 6-20, more preferably 6-16, particularly preferably 6-12, such as phenyloxy group, 2-naphthyloxy group, etc.), acyl group (preferably Has 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms such as acetyl, benzoyl, Group, pivaloyl group, etc.), alkoxycarbonyl group (preferably having 2-20 carbon atoms, more preferably 2-16, particularly preferably 2-12, such as methoxycarbonyl group, ethoxycarbonyl group, etc.), aryloxycarbonyl group (Preferably 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 10 carbon atoms such as phenyloxycarbonyl group), acyloxy groups (preferably 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms). And particularly preferably 2 to 10, for example, an acetoxy group, a benzoyloxy group, etc.), an acylamino group (preferably 2 to 20, more preferably 2 to 16, particularly preferably 2 to 10, such as acetylamino) Group, benzoylamino group, etc.), alkoxycarbonylamino group (preferably carbon number) 2 to 20, more preferably 2 to 16, particularly preferably 2 to 12, for example, methoxycarbonylamino group, etc., aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably 7 to 16, particularly Preferably it is 7-12, for example, phenyloxycarbonylamino group, etc., sulfonylamino group (preferably 1-20 carbon atoms, more preferably 1-16, particularly preferably 1-12, for example, methanesulfonylamino group , Benzenesulfonylamino group, etc.), sulfamoyl group (preferably having 0 to 20 carbon atoms, more preferably 0 to 16, particularly preferably 0 to 12, such as sulfamoyl group, methylsulfamoyl group, dimethylsulfamoyl group) , Phenylsulfamoyl group, etc.), carbamoyl group (preferably carbon number) -20, more preferably 1-16, particularly preferably 1-12. For example, carbamoyl group, methylcarbamoyl group, diethylcarbamoyl group, phenylcarbamoyl group, etc., alkylthio group (preferably having 1-20 carbon atoms, more preferably Is 1 to 16, particularly preferably 1 to 12, for example, methylthio group, ethylthio group, etc.), arylthio group (preferably 6 to 20, more preferably 6 to 16, particularly preferably 6 to 12, For example, a phenylthio group, etc.), a sulfonyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms such as a mesyl group and a tosyl group). ), A sulfinyl group (preferably having a carbon number of 1 to 20, more preferably 1 to 16, particularly preferably 1 to 12, such as a methanesulfinyl group, a benzenesulfinyl group, etc.), a ureido group (preferably having a carbon number of 1 to 20). More preferably, it is 1-16, Most preferably, it is 1-12, for example, a ureido group, a methylureido group, a phenylureido group etc., a phosphoric acid amide group (preferably C1-C20, more preferably 1-16) , Particularly preferably 1 to 12, such as diethyl phosphoric acid amide and phenyl phosphoric acid amide), a hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), a cyano group, Sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, Rocyclic group (preferably having 1 to 30 carbon atoms, more preferably 1 to 12 carbon atoms, and examples of the hetero atom include a nitrogen atom, an oxygen atom and a sulfur atom, specifically, for example, an imidazolyl group, a pyridyl group and a quinolyl group. , Furyl group, piperidyl group, morpholino group, benzoxazolyl group, benzimidazolyl group, benzthiazolyl group, etc.), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms). And examples thereof include trimethylsilyl group and triphenylsilyl group. These substituents may be further substituted. Moreover, 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.

  Preferred examples of the compound represented by the general formula (7) are shown below, but the present invention is not limited to these specific examples.

  Compounds of general formula (5), general formula (6), and general formula (7) are obtained by dehydration condensation reaction of carboxylic acids with amines using a condensing agent (for example, dicyclohexylcarbodiimide (DCC)), or carboxylic acid It can be obtained by a substitution reaction between a chloride derivative and an amine derivative.

  As the retardation reducing agent used in the present invention, many compounds known as cellulose acylate plasticizers can be usefully used. As the plasticizer, phosphoric acid ester or carboxylic acid ester is used. Examples of phosphate esters include triphenyl phosphate (TPP) and tricresyl phosphate (TCP). Representative examples of the carboxylic acid ester include phthalic acid esters and citric acid esters. Examples of phthalic acid esters include dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), dioctyl phthalate (DOP), diphenyl phthalate (DPP) and diethyl hexyl phthalate (DEHP). Examples of citrate esters include triethyl O-acetylcitrate (OACTE) and tributyl O-acetylcitrate (OACTB). Examples of other carboxylic acid esters include butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, and various trimellitic acid esters. Phthalate plasticizers (DMP, DEP, DBP, DOP, DPP, DEHP) are preferably used. DEP and DPP are particularly preferred.

  The retardation reducing agent used in the present invention is preferably an Rth reducing agent. Among the retardation reducing agents, examples of the Rth reducing agent include aliphatic polyesters, acrylic polymers and styrene polymers, and low molecular compounds represented by the general formulas (3) to (7). Aliphatic polyesters, acrylic polymers and styrenic polymers are preferred, and aliphatic polyesters and acrylic polymers are more preferred.

  The retardation reducing agent is preferably added in a proportion of 0.01 to 30% by mass, more preferably 0.1 to 20% by mass, more preferably 0.1 to 10%, based on cellulose acylate. It is particularly preferable to add at a ratio of mass%.

  By making the said addition amount 30 mass% or less, compatibility with a cellulose acylate can be improved and whitening can be suppressed. When using two or more types of retardation reducing agents, the total amount is preferably within the above range.

(Retardation expression agent)
In the present invention, in order to develop retardation, those composed of rod-like or discotic compounds can be mentioned. As the rod-like or discotic compound, a compound having at least two aromatic rings can be preferably used as a retardation developer.

  The addition amount of the retardation enhancer composed of the rod-shaped compound is preferably 0.1 to 30 parts by mass, and preferably 0.5 to 20 parts by mass with respect to 100 parts by mass of the polymer component containing cellulose acylate. Further preferred. The discotic retardation enhancer is preferably used in a range of 0.05 to 20 parts by mass, and in a range of 1.0 to 15 parts by mass with respect to 100 parts by mass of the polymer component containing the cellulose acylate. It is more preferable to use, and it is still more preferable to use in the range of 3.0-10 mass parts.

  Since the discotic compound is superior to the rod-shaped compound in Rth retardation expression, it is preferably used when a particularly large Rth retardation is required. Two or more retardation developers may be used in combination.

  The retardation developer preferably has a 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. 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.

  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. As the hetero atom, a nitrogen atom, an oxygen atom and a sulfur atom are preferable, and a nitrogen atom is particularly preferable. 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.

  As the aromatic ring, a benzene ring, a condensed benzene ring, and biphenyls are preferable. In particular, a 1,3,5-triazine ring is preferably used. Specifically, for example, compounds disclosed in JP-A No. 2001-166144 are preferably used.

  The number of carbon atoms of the aromatic ring in the retardation enhancer is preferably 2-20, more preferably 2-12, still more preferably 2-8, and 2-6. Most preferred.

  The bonding relationship between two aromatic rings can be classified into (a) when a condensed ring is formed, (b) when directly linked by a single bond, and (c) when linked via a linking group (for aromatic rings). , Spiro bonds cannot be formed). The connection relationship may be any of (a) to (c).

  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 thiant It includes emissions ring. 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 with 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.

  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.

  It is preferable that the alkyl group has 1 to 8 carbon atoms. 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 (for example, a hydroxy group, a carboxy group, an alkoxy group, an alkyl-substituted amino group). Examples of alkyl groups (including substituted alkyl groups) include methyl, ethyl, n-butyl, n-hexyl, 2-hydroxyethyl, 4-carboxybutyl, 2-methoxyethyl, and 2- Each group of 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 alkynyl group preferably has 2 to 8 carbon atoms. 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 (for example, an 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 2-10. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group.

  The number of carbon atoms of the alkoxycarbonylamino group is preferably 2-10. Examples of the alkoxycarbonylamino group include a methoxycarbonylamino group and an ethoxycarbonylamino group.

  The alkylthio group preferably has 1 to 12 carbon atoms. Examples of the alkylthio group include a methylthio group, an ethylthio group, and an octylthio group.

  The alkylsulfonyl group preferably has 1 to 8 carbon atoms. 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 acetamide.

  The number of carbon atoms of 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 2-10. Examples of the aliphatic substituted carbamoyl group include a methylcarbamoyl group and a diethylcarbamoyl group.

  The number of carbon atoms in 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 in the aliphatic substituted ureido group is preferably 2-10. Examples of the aliphatic substituted ureido group include a methylureido group.

  Examples of the non-aromatic heterocyclic group include a piperidino group and a morpholino group.

  The molecular weight of the retardation developer is preferably 300 to 800.

  As the discotic compound, a triazine compound represented by the following general formula (I) is preferably used.

In the above general formula (I):
R ²⁰¹ each independently represents an aromatic ring or a heterocyclic ring having a substituent in at least one of the ortho, meta and para positions.

X ²⁰¹ each independently represents a single bond or —NR ²⁰² —. Here, each R ²⁰² independently represents a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, an aryl group, or a heterocyclic group.

The aromatic ring represented by R ²⁰¹ is preferably phenyl or naphthyl, and particularly preferably phenyl. The aromatic ring represented by R ²⁰¹ may have at least one substituent at any substitution position. Examples of the substituent include a halogen atom, hydroxyl group, cyano group, nitro group, carboxyl group, alkyl group, alkenyl group, aryl group, alkoxy group, alkenyloxy group, aryloxy group, acyloxy group, alkoxycarbonyl group, Alkenyloxycarbonyl group, aryloxycarbonyl group, sulfamoyl group, alkyl-substituted sulfamoyl group, alkenyl-substituted sulfamoyl group, aryl-substituted sulfamoyl group, sulfonamide group, carbamoyl, alkyl-substituted carbamoyl group, alkenyl-substituted carbamoyl group, aryl-substituted carbamoyl group, amide Groups, alkylthio groups, alkenylthio groups, arylthio groups and acyl groups.

The heterocyclic group represented by R ²⁰¹ preferably has aromaticity. The heterocycle having aromaticity is generally an unsaturated heterocycle, preferably a heterocycle having the largest number of double bonds. The heterocyclic ring is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring, and most preferably a 6-membered ring. The hetero atom of the heterocyclic ring is preferably a nitrogen atom, a sulfur atom or an oxygen atom, and particularly preferably a nitrogen atom. As the heterocyclic ring having aromaticity, a pyridine ring (2-pyridyl or 4-pyridyl as the heterocyclic group) is particularly preferable. The heterocyclic group may have a substituent. Examples of the substituent of the heterocyclic group are the same as the examples of the substituent of the aryl moiety.

When X ²⁰¹ is a single bond, the heterocyclic group is preferably a heterocyclic group having a free valence on the nitrogen atom. The heterocyclic group having a free valence on the nitrogen atom is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring, and a 5-membered ring. Is most preferred. The heterocyclic group may have a plurality of nitrogen atoms. Further, the heterocyclic group may have a hetero atom other than the nitrogen atom (for example, O, S). Examples of heterocyclic groups having free valences on nitrogen atoms are shown below. Here, _-C 4 _{H 9} n represents a _n-C 4 _{H 9.}

The alkyl group represented by R ²⁰² may be a cyclic alkyl group or a chain alkyl group, but a chain alkyl group is preferable, and a linear alkyl group is more preferable than a branched chain alkyl group. preferable. The number of carbon atoms in the alkyl group is preferably 1-30, more preferably 1-20, further preferably 1-10, still more preferably 1-8, and 1-6. Most preferred. The alkyl group may have a substituent. Examples of the substituent include a halogen atom, an alkoxy group (for example, methoxy group, ethoxy group) and an acyloxy group (for example, acryloyloxy group, methacryloyloxy group).

The alkenyl group represented by R ²⁰² may be a cyclic alkenyl group or a chain alkenyl group, but is preferably a chain alkenyl group, and is a straight chain alkenyl group rather than a branched chain alkenyl group. More preferably it represents a group. The number of carbon atoms in the alkenyl group is preferably 2 to 30, more preferably 2 to 20, still more preferably 2 to 10, still more preferably 2 to 8, 6 is most preferred. The alkenyl group may have a substituent. Examples of the substituent are the same as those of the alkyl group described above.

The aromatic ring group and heterocyclic group represented by R ²⁰² are the same as the aromatic ring and heterocyclic ring represented by R ²⁰¹ , and the preferred range is also the same. The aromatic ring group and the heterocyclic group may further have a substituent, and examples of the substituent are the same as those of the aromatic ring and heterocyclic ring of ^R201 .

  Although the specific example of a compound represented by general formula (I) below is given, it is not limited to this.

  As the discotic compound, a triphenylene compound represented by the following general formula (II) can also be preferably used.

In the general formula (II), R ^{203 to} R ²⁰⁸ each independently represent a hydrogen atom or a substituent.

Examples of the substituent represented by each of R ^{203 to} R ²⁰⁸ include an alkyl group (preferably an alkyl group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and particularly preferably 1 to 20 carbon atoms. Group, ethyl group, isopropyl group, tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (preferably carbon An alkenyl group having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, particularly preferably 2 to 20 carbon atoms, and examples thereof include a vinyl group, an allyl group, a 2-butenyl group, and a 3-pentenyl group. An alkynyl group (preferably an alkynyl group having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, and particularly preferably 2 to 20 carbon atoms. For example, a propargyl group, 3-pentynyl group, etc.), an aryl group (preferably an aryl group having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 12 carbon atoms). A phenyl group, a p-methylphenyl group, a naphthyl group, etc.), a substituted or unsubstituted amino group (preferably having 0 to 40 carbon atoms, more preferably 0 to 30 carbon atoms, and particularly preferably carbon number). An amino group having 0-20, for example, an unsubstituted amino group, a methylamino group, a dimethylamino group, a diethylamino group, an anilino group, etc., an alkoxy group (preferably having 1 to 40 carbon atoms, more preferably carbon An alkoxy group having 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, such as a methoxy group, an ethoxy group, and a butoxy group. An aryloxy group (preferably an aryloxy group having 6 to 40 carbon atoms, more preferably 6 to 30 carbon atoms, and particularly preferably 6 to 20 carbon atoms, such as a phenyloxy group and a 2-naphthyloxy group. Etc.), an acyl group (preferably an acyl group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, for example, an acetyl group, a benzoyl group, a formyl group And a pivaloyl group), an alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 40 carbon atoms, more preferably 2 to 30 carbon atoms, particularly preferably 2 to 20 carbon atoms, such as a methoxycarbonyl group. , An ethoxycarbonyl group, etc.), an aryloxycarbonyl group (preferably having 7 to 40 carbon atoms, more preferably Is an aryloxycarbonyl group having 7 to 30 carbon atoms, particularly preferably 7 to 20 carbon atoms, such as a phenyloxycarbonyl group, and an acyloxy group (preferably having 2 to 40 carbon atoms, more preferably carbon. An acyloxy group having 2 to 30 carbon atoms, particularly preferably 2 to 20 carbon atoms, and examples thereof include an acetoxy group and a benzoyloxy group), an acylamino group (preferably 2 to 40 carbon atoms, more preferably 2 carbon atoms). To 30 and particularly preferably an acylamino group having 2 to 20 carbon atoms, such as an acetylamino group and a benzoylamino group, and an alkoxycarbonylamino group (preferably having 2 to 40 carbon atoms, more preferably 2 carbon atoms). To 30 and particularly preferably an alkoxycarbonylamino group having 2 to 20 carbon atoms, for example, Toxylcarbonylamino group), aryloxycarbonylamino group (preferably 7 to 40 carbon atoms, more preferably 7 to 30 carbon atoms, particularly preferably 7 to 20 carbon atoms aryloxycarbonylamino group, Examples thereof include a phenyloxycarbonylamino group), a sulfonylamino group (preferably a sulfonylamino group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and particularly preferably 1 to 20 carbon atoms. , A methanesulfonylamino group, a benzenesulfonylamino group and the like), a sulfamoyl group (preferably a sulfamoyl group having 0 to 40 carbon atoms, more preferably 0 to 30 carbon atoms, particularly preferably 0 to 20 carbon atoms, For example, sulfamoyl group, methylsulfamoyl group, dimethyls And a carbamoyl group (preferably a carbamoyl group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and particularly preferably 1 to 20 carbon atoms). An unsubstituted carbamoyl group, a methylcarbamoyl group, a diethylcarbamoyl group, a phenylcarbamoyl group, and the like, an alkylthio group (preferably having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, and particularly preferably 1 to carbon atoms). 20, for example, methylthio group, ethylthio group, propylthio group, butylthio group, pentylthio group, hexylthio group, heptylthio group, octylthio group, etc.), arylthio group (preferably having 6 to 40 carbon atoms, more preferably 6 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, for example A phenylthio group), a sulfonyl group (preferably a sulfonyl group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, such as mesyl group, tosyl A sulfinyl group (preferably a sulfinyl group having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, such as a methanesulfinyl group and a benzenesulfinyl group). Ureido groups (preferably having 1 to 40 carbon atoms, more preferably 1 to 30 carbon atoms, particularly preferably 1 to 20 carbon atoms, and examples thereof include unsubstituted ureido groups and methylureido groups. Groups, phenylureido groups, etc.), phosphoric acid amide groups (preferably having 1 to 40 carbon atoms, more preferably 1 to 1 carbon atoms). 0, particularly preferably a phosphoric acid amide group having 1 to 20 carbon atoms, such as a diethylphosphoric acid amide group and a phenylphosphoric acid amide group, a hydroxy group, a mercapto group, a halogen atom (for example, a 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 heterocyclic groups, for example, a heterocyclic group having a heteroatom such as nitrogen atom, oxygen atom, sulfur atom, etc., for example, imidazolyl group, pyridyl group, quinolyl group, furyl group, piperidyl group, morpholino Group, benzoxazolyl group, benzimidazolyl group, benzthiazolyl group, 1,3,5-triazyl group, etc. A silyl group (preferably a silyl group having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms, such as a trimethylsilyl group and a triphenylsilyl group). Included). These substituents may be further substituted with these substituents. Moreover, when it has two or more substituents, they may be the same or different. If possible, they may be bonded to each other to form a ring.

The substituent represented by each of R ^{203 to} R ²⁰⁸ is preferably an alkyl group, an aryl group, a substituted or unsubstituted amino group, an alkoxy group, an alkylthio group, or a halogen atom.

  Although the specific example of a compound represented by general formula (II) below is given, it is not limited to this.

  The compound represented by the general formula (I) is, for example, a method described in JP-A No. 2003-344655, and the compound represented by the general formula (II) is, for example, a method described in JP-A-2005-134484. Can be synthesized by a known method.

  In the present invention, rod-like compounds having a linear molecular structure can be preferably used in addition to the above-mentioned discotic compounds. 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. For example, molecular orbital calculation is performed using molecular orbital calculation software (for example, WinMOPAC2000, manufactured by Fujitsu Limited), and a molecular structure that minimizes the heat of formation of a compound can be obtained. The molecular structure being linear means that in the thermodynamically most stable structure obtained by calculation as described above, the angle of the main chain constituting the molecular structure is 140 degrees or more.

  As the rod-shaped compound having at least two aromatic rings, a compound represented by the following general formula (11) is preferable.

Formula (11): Ar ¹ -L ¹ -Ar ²
In the general formula (11), Ar ¹ and Ar ² are each independently an aromatic group.

  In the present specification, the aromatic group includes an aryl group (aromatic hydrocarbon group), a substituted aryl group, an aromatic heterocyclic group, and 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 heterocyclic ring 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 heterocycles 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. 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. .

  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 (for example, methyl Amino group, ethylamino group, butylamino group, dimethylamino group), nitro group, sulfo group, carbamoyl group, alkylcarbamoyl group (for example, 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 (for example, N-methylureido group, N, N-dimethylureido group, N, N, N′-tri group) Each group of tilureido group), alkyl group (for example, methyl group, ethyl group, propyl group, butyl group, pentyl group, heptyl group, octyl group, isopropyl group, s-butyl group, tert-amyl group, cyclohexyl group, cyclopentyl) Group), alkenyl group (for example, vinyl group, allyl group, hexenyl group), alkynyl group (for example, ethynyl group, butynyl group), acyl group (for example, formyl group, acetyl group, butyryl group, Hexanoyl group, lauryl group), acyloxy group (for example, acetoxy group, butyryloxy group, hexanoyloxy group, lauryloxy group), alkoxy group (for example, methoxy group, ethoxy group, propoxy group, butoxy group) , Pentyloxy group, heptyloxy group, octyloxy group), aryl Xy group (for example, phenoxy group), alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, propoxycarbonyl group, butoxycarbonyl group, pentyloxycarbonyl group, heptyloxycarbonyl group), aryloxycarbonyl group ( For example, phenoxycarbonyl group), alkoxycarbonylamino group (for example, butoxycarbonylamino group, hexyloxycarbonylamino group), alkylthio group (for example, methylthio group, ethylthio group, propylthio group, butylthio group, pentylthio group, heptylthio group, octylthio group) Each group), arylthio group (for example, phenylthio group), alkylsulfonyl group (for example, methylsulfonyl group, ethylsulfonyl group, propylsulfonyl group, butylsulfo group) Nyl group, pentylsulfonyl group, heptylsulfonyl group, octylsulfonyl group), amide group (for example, acetamido group, butyramide group, hexylamide group, laurylamide group) and non-aromatic heterocyclic group ( For example, a morpholyl group and a pyrazinyl group) are included.

  Among these, preferred substituents include halogen atoms, cyano groups, carboxyl groups, hydroxyl groups, amino groups, alkylamino groups, acyl groups, acyloxy groups, amide groups, alkoxycarbonyl groups, alkoxy groups, alkylthio groups, and alkyl groups. Can be mentioned.

  The alkyl part and alkyl group of the alkylamino group, alkoxycarbonyl group, alkoxy group and alkylthio group may further have a substituent. Examples of the alkyl moiety and the substituent of the alkyl group include halogen atom, hydroxyl group, carboxyl group, cyano group, amino group, alkylamino group, nitro group, sulfo group, carbamoyl group, alkylcarbamoyl group, sulfamoyl group, alkylsulfur group. Famoyl group, ureido group, alkylureido group, alkenyl group, alkynyl group, acyl group, acyloxy group, alkoxy group, aryloxy group, alkoxycarbonyl group, aryloxycarbonyl group, alkoxycarbonylamino group, alkylthio group, arylthio group, An alkylsulfonyl group, an amide group and a non-aromatic heterocyclic group are included. As the substituent for the alkyl moiety and the alkyl group, a halogen atom, a hydroxyl group, an amino group, an alkylamino group, an acyl group, an acyloxy group, an acylamino group, an alkoxycarbonyl group, and an alkoxy group are preferable.

In the general formula (11), 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. 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.

  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 alkenylene group and the alkynylene group preferably have 2 to 10 carbon atoms, more preferably 2 to 8, more preferably 2 to 6, still more preferably 2 to 4, and most preferably 2. (Vinylene group or ethynylene group).

  The arylene group preferably has 6 to 20 carbon atoms, more preferably 6 to 16, and still more preferably 6 to 12.

In the molecular structure of the general formula (11), the angle formed by Ar ¹ and Ar ² across L ¹ is preferably 140 degrees or more.

  As the rod-like compound, a compound represented by the following formula (12) is more preferable.

Formula ^{(12): Ar 1 -L 2} -X-L 3 -Ar 2
In the general formula (12), Ar ¹ and Ar ² are each independently an aromatic group. The definition and examples of the aromatic group are the same as those of Ar ¹ and Ar ^{2 in} the general formula (12).

In General Formula (12), L ² and L ³ are each independently a divalent linking group selected from an alkylene group, —O—, —CO—, and a group consisting of a combination thereof.

  The alkylene group preferably has a chain structure rather than a cyclic structure, and more preferably has a linear structure rather than a branched chain structure.

  The alkylene group preferably has 1 to 10 carbon atoms, more preferably 1 to 8, more preferably 1 to 6, still more preferably 1 to 4, and 1 or 2 (methylene group). Or ethylene group).

L ² and L ³ are particularly preferably —O—CO— or —CO—O—.

  In the general formula (12), X is a 1,4-cyclohexylene group, a vinylene group or an ethynylene group.

  Specific examples of the compound represented by the general formula (11) or (12) include compounds described in [Chemical Formula 1] to [Chemical Formula 11] of JP-A No. 2004-109657.

  Two or more rod-shaped compounds whose maximum absorption wavelength (λmax) is longer than 250 nm in the ultraviolet absorption spectrum of the solution may be used in combination.

  The rod-like compound can be synthesized with reference to methods described in literature. As literature, Mol. Cryst. Liq. Cryst. 53, 229 pages (1979), 89, 93 pages (1982), 145, 111 pages (1987), 170 pages, 43 pages (1989), J. Am. Am. Chem. Soc. 113, p. 1349 (1991), p. 118, p. 5346 (1996), p. 92, p. 1582 (1970). Org. Chem. , 40, 420 (1975), Tetrahedron, 48, 16, 3437 (1992).

  Moreover, you may use the rod-shaped aromatic compound of pages 11-14 of Unexamined-Japanese-Patent No. 2004-50516 as said Re expression agent.

  In addition, as the retardation developer, one kind of compound can be used alone, or two or more kinds of compounds can be mixed and used. It is preferable to use two or more different compounds as the retardation enhancer because the adjustment range of retardation is widened and can be easily adjusted to a desired range.

  When the cellulose acylate film is produced by a solvent cast method, the retardation developer may be added to the dope. The addition may be performed at any timing, for example, the retardation developer may be dissolved in an organic solvent such as alcohol, methylene chloride, dioxolane, and then added to the cellulose acylate solution (dope), or You may add directly in dope composition.

  In addition, specific examples of preferable compounds of rod-like compounds other than those described in the above-mentioned publications are shown below.

  The specific examples (1) to (34), (41), and (42) have two asymmetric carbon atoms at the 1-position and the 4-position of the cyclohexane ring. However, since the specific examples (1), (4) to (34), (41), and (42) have a symmetrical meso type molecular structure, there are no optical isomers (optical activity), and geometric isomers (trans Type and cis type). The trans type (1-trans) and cis type (1-cis) of specific example (1) are shown below.

  As described above, the rod-like compound preferably has a linear molecular structure. Therefore, the trans type is preferable to the cis type.

  Specific examples (2) and (3) have optical isomers (a total of four isomers) in addition to geometric isomers. As for geometric isomers, the trans type is similarly preferable to the cis type. The optical isomer is not particularly superior or inferior, and may be D, L, or a racemate.

  In specific examples (43) to (45), the central vinylene bond includes a trans type and a cis type. For the same reason as above, the trans type is preferable to the cis type.

<Plasticizers useful in the present invention>
The cellulose acylate film according to the present invention preferably contains the following sugar ester compound and ester compound as a plasticizer. In particular, the protective film A is preferably contained.

<Compound represented by formula (FA)>
It is preferable that the cellulose acylate film which concerns on this invention contains the compound whose total average substitution degree represented by the following general formula (FA) is 3.0-6.0.

  A compound represented by the general formula (FA) according to the present invention (also referred to as a sugar ester compound in the present invention) and a reference compound are described below, but the present invention is not limited thereto.

  The average substitution degree of the compound represented by the general formula (FA) according to the present invention is 3.0 to 6.0 in order to prevent an increase in haze in the stretching treatment.

In the present invention, the degree of substitution of the compound represented by the general formula (FA) represents the number substituted with a substituent other than hydrogen among the eight hydroxyl groups contained in the general formula (FA). among _R 1 to R ₈ of general formula (FA), it represents a number that contains a group other than hydrogen. Therefore, when all of R _{1 to} R ₈ are substituted with a substituent other than hydrogen, the degree of substitution is 8.0, which is the maximum value, and when R _{1 to} R ₈ are all hydrogen atoms, 0.0 It becomes.

  The compound having the structure represented by the general formula (FA) is difficult to synthesize a single kind of compound in which the number of hydroxyl groups and the number of OR groups are fixed. Since it is known that it becomes a compound in which several different components are mixed, it is appropriate to use the average substitution degree as the substitution degree of the general formula (FA) in the present invention. The average substitution degree can be measured from the area ratio of the chart showing the substitution degree distribution.

In General Formula (FA), R _{1 to} R ₈ represent a substituted or unsubstituted alkylcarbonyl group or a substituted or unsubstituted allylcarbonyl group, and R _{1 to} R ₈ may be the same or different. It may be.

  Examples of the sugar as a raw material for synthesizing the sugar ester compound according to the present invention include the following, but the present invention is not limited thereto.

  Glucose, galactose, mannose, fructose, xylose or arabinose, lactose, sucrose, nystose, 1F-fructosyl nystose, stachyose, maltitol, lactitol, lactulose, cellobiose, maltose, cellotriose, maltotriose, raffinose or kestose .

  In addition, gentiobiose, gentiotriose, gentiotetraose, xylotriose, galactosyl sucrose, and the like are also included.

  There is no restriction | limiting in particular as monocarboxylic acid used at the time of the synthesis | combination of the sugar ester compound based on this invention, Well-known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, aromatic monocarboxylic acid, etc. can be used. The carboxylic acid used may be one type or a mixture of two or more types.

  Examples of preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanecarboxylic acid, undecylic acid, Saturation of lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, mellicic acid, and laxaric acid Examples thereof include unsaturated fatty acids such as fatty acids, undecylenic acid, oleic acid, sorbic acid, linoleic acid, linolenic acid, arachidonic acid and octenoic acid.

  Examples of preferred alicyclic monocarboxylic acids include cyclopentane carboxylic acid, cyclohexane carboxylic acid, cyclooctane carboxylic acid, or derivatives thereof.

  Examples of preferable aromatic monocarboxylic acids include aromatic monocarboxylic acids having 1 to 5 alkyl groups or alkoxy groups introduced into the benzene ring of benzoic acid such as benzoic acid and toluic acid, cinnamic acid, benzylic acid, An aromatic monocarboxylic acid having two or more benzene rings such as biphenyl carboxylic acid, naphthalene carboxylic acid, tetralin carboxylic acid, or a derivative thereof can be exemplified, and benzoic acid is particularly preferable.

  Some specific examples are shown below, but the present invention is not limited thereto.

  (Synthesis Example: Synthesis of Compound According to the Present Invention)

A four-headed colben equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen gas inlet tube was mixed with 34.2 g (0.1 mol) of sucrose, 180.8 g (0.8 mol) of benzoic anhydride, 379. 7 g (4.8 mol) was charged, the temperature was raised while bubbling nitrogen gas from a nitrogen gas introduction tube with stirring, and an esterification reaction was carried out at 70 ° C. for 5 hours. Next, the inside of the Kolben was depressurized to 4 × 10 ² Pa or less, and after excess pyridine was distilled off at 60 ° C., the inside of the Kolben was depressurized to 1.3 × 10 Pa or less and the temperature was raised to 120 ° C. Most of the acid and benzoic acid formed were distilled off. Then, 1 L of toluene and 300 g of a 0.5% by mass aqueous sodium carbonate solution were added, and the mixture was stirred at 50 ° C. for 30 minutes and then allowed to stand to separate a toluene layer. Finally, 100 g of water is added to the collected toluene layer, and after washing with water at room temperature for 30 minutes, the toluene layer is separated, and toluene is distilled off at 60 ° C. under reduced pressure (4 × 10 ² Pa or less). A mixture of A-1, A-2, A-3, A-4 and A-5 was obtained. When the obtained mixture was analyzed by HPLC and LC-MASS, A-1 was 7% by mass, A-2 was 58% by mass, A-3 was 23% by mass, A-4 was 9% by mass, A-5. Was 3% by mass. A part of the obtained mixture was purified by column chromatography using silica gel to obtain A-1, A-2, A-3, A-4 and A-5 having a purity of 100%, respectively. .

  Then, when average substitution degree was measured from the area ratio of the chart which shows substitution degree distribution by a high performance liquid chromatography by a conventional method, it is 1.3%, 13.4%, and 13.1% from A-1 to A-5, respectively. 31.7% and 40.5% in mass ratio, and the average degree of substitution was 5.5.

  The average degree of substitution of the compound represented by the general formula (1) added to the retardation film in the present invention is preferably 4.5 to 6.0, and the distribution range of the degree of substitution is 4.0 to 8. 0.0 is preferred. Furthermore, it is preferable that the content ratio of the component having a substitution degree of 8.0 is 2% or less.

  The distribution of the degree of substitution is made by adjusting the esterification reaction time, but may be adjusted to the target average degree of substitution by mixing compounds having different degrees of substitution.

<Ester compound represented by formula (FB)>
The cellulose acylate film according to the present invention preferably contains an ester compound represented by the following general formula (FB) as a plasticizer.

Formula (FB) B- (GA) n-GB
(Wherein B is a hydroxy group or carboxylic acid residue, G is an alkylene glycol residue having 2 to 12 carbon atoms, an aryl glycol residue having 6 to 12 carbon atoms, or an oxyalkylene glycol residue having 4 to 12 carbon atoms) , A represents an alkylene dicarboxylic acid residue having 4 to 12 carbon atoms or an aryl dicarboxylic acid residue having 6 to 12 carbon atoms, and n represents an integer of 1 or more.)
In the general formula (FB), as the alkylene glycol component having 2 to 12 carbon atoms, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,2-propanediol, 2-methyl 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2 , 2-diethyl-1,3-propanediol (3,3-dimethylolpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolheptane), 3-methyl- 1,5-pentanediol 1,6-hexanediol, 2,2,4-trimethyl 1,3-pentanediol, 2-ethyl 1 There are 3-hexanediol, 2-methyl 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,12-octadecanediol, etc., and these glycols are one kind or two or more kinds Used as a mixture.

  In particular, an alkylene glycol having 2 to 12 carbon atoms is particularly preferable because of excellent compatibility with cellulose acetate.

  Examples of the aryl glycol component having 6 to 12 carbon atoms include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol and the like, and these glycols can be used as one kind or a mixture of two or more kinds.

  Examples of the oxyalkylene glycol component having 4 to 12 carbon atoms include diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, and tripropylene glycol. These glycols may be used alone or in combination of two or more. Can be used as a mixture.

  Examples of the alkylene dicarboxylic acid component having 4 to 12 carbon atoms include succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, and the like. Used as a mixture of two or more. Examples of the arylene dicarboxylic acid component having 6 to 12 carbon atoms include phthalic acid, terephthalic acid, isophthalic acid, 1,5 naphthalene dicarboxylic acid, 1,4 naphthalene dicarboxylic acid, and 2,6-naphthalene dicarboxylic acid.

  Although the specific compound of the ester compound represented by general formula (FB) used for this invention below is shown, this invention is not limited to this.

<Other additives>
(Other plasticizers)
The protective film A or the protective film B according to the present invention can contain a plasticizer other than the above-described plasticizer as necessary for obtaining the effects of the present invention.

  The plasticizer is not particularly limited, but is preferably a polycarboxylic acid ester plasticizer, a glycolate plasticizer, a phthalate ester plasticizer, a fatty acid ester plasticizer, a polyhydric alcohol ester plasticizer, or an ester plasticizer. Agent, acrylic plasticizer and the like.

  Of these, when two or more plasticizers are used, at least one plasticizer is preferably a polyhydric alcohol ester plasticizer.

  The polyhydric alcohol ester plasticizer is a plasticizer comprising an ester of a dihydric or higher aliphatic polyhydric alcohol and a monocarboxylic acid, and preferably has an aromatic ring or a cycloalkyl ring in the molecule. Preferably it is a 2-20 valent aliphatic polyhydric alcohol ester.

  The polyhydric alcohol preferably used in the present invention is represented by the following general formula (a).

Formula _{(a) R 11 - (OH} ) n
However, R ₁₁ represents an n-valent organic group, n represents a positive integer of 2 or more, and the OH group represents an alcoholic and / or phenolic hydroxyl group.

  Examples of preferred polyhydric alcohols include the following, but the present invention is not limited to these.

  Adonitol, arabitol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, 1,3- Butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol, 1,6-hexanediol, hexanetriol, galactitol, mannitol, 3-methylpentane- Examples include 1,3,5-triol, pinacol, sorbitol, trimethylolpropane, trimethylolethane, xylitol and the like.

  In particular, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane, and xylitol are preferable.

  There is no restriction | limiting in particular as monocarboxylic acid used for polyhydric alcohol ester, Well-known aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, aromatic monocarboxylic acid, etc. can be used. Use of an alicyclic monocarboxylic acid or aromatic monocarboxylic acid is preferred in terms of improving moisture permeability and retention.

  Examples of preferred monocarboxylic acids include the following, but the present invention is not limited thereto.

  As the aliphatic monocarboxylic acid, a fatty acid having a straight chain or side chain having 1 to 32 carbon atoms can be preferably used. The number of carbon atoms is more preferably 1-20, and particularly preferably 1-10. When acetic acid is contained, the compatibility with cellulose acylate is increased, and it is also preferable to use a mixture of acetic acid and another monocarboxylic acid.

  Preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanoic acid, undecylic acid, lauric acid, tridecylic acid, Saturated fatty acids such as myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, melicic acid, laccelic acid, undecylenic acid, olein Examples thereof include unsaturated fatty acids such as acid, sorbic acid, linoleic acid, linolenic acid, and arachidonic acid.

  Examples of preferred alicyclic monocarboxylic acids include cyclopentane carboxylic acid, cyclohexane carboxylic acid, cyclooctane carboxylic acid, or derivatives thereof.

  Examples of preferred aromatic monocarboxylic acids include those in which 1 to 3 alkoxy groups such as an alkyl group, a methoxy group or an ethoxy group are introduced into the benzene ring of benzoic acid such as benzoic acid or toluic acid, biphenylcarboxylic acid, Examples thereof include aromatic monocarboxylic acids having two or more benzene rings such as naphthalenecarboxylic acid and tetralincarboxylic acid, or derivatives thereof. Benzoic acid is particularly preferable.

  The molecular weight of the polyhydric alcohol ester is not particularly limited, but is preferably 300 to 1500, and more preferably 350 to 750. A higher molecular weight is preferable because it is less likely to volatilize, and a lower molecular weight is preferable in terms of moisture permeability and compatibility with cellulose acylate.

  The carboxylic acid used for the polyhydric alcohol ester may be one kind or a mixture of two or more kinds. Moreover, all the OH groups in the polyhydric alcohol may be esterified, or a part of the OH groups may be left as they are.

  Below, the specific compound of a polyhydric alcohol ester is illustrated.

  The glycolate plasticizer is not particularly limited, but alkylphthalylalkyl glycolates can be preferably used.

  Examples of alkyl phthalyl alkyl glycolates include methyl phthalyl methyl glycolate, ethyl phthalyl ethyl glycolate, propyl phthalyl propyl glycolate, butyl phthalyl butyl glycolate, octyl phthalyl octyl glycolate, methyl phthalyl ethyl Glycolate, ethyl phthalyl methyl glycolate, ethyl phthalyl propyl glycolate, methyl phthalyl butyl glycolate, ethyl phthalyl butyl glycolate, butyl phthalyl methyl glycolate, butyl phthalyl ethyl glycolate, propyl phthalyl butyl glycol Butyl phthalyl propyl glycolate, methyl phthalyl octyl glycolate, ethyl phthalyl octyl glycolate, octyl phthalyl methyl glycolate, octyl phthalate Ethyl glycolate, and the like.

  Examples of the phthalate ester plasticizer include diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, and dicyclohexyl terephthalate.

  Examples of the citrate plasticizer include acetyl trimethyl citrate, acetyl triethyl citrate, and acetyl tributyl citrate.

  Examples of fatty acid ester plasticizers include butyl oleate, methylacetyl ricinoleate, and dibutyl sebacate.

  Examples of the phosphate ester plasticizer include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate and the like.

  The polyvalent carboxylic acid ester compound is composed of an ester of divalent or higher, preferably divalent to 20 valent polyvalent carboxylic acid and alcohol. The aliphatic polyvalent carboxylic acid is preferably 2 to 20 valent, and in the case of an aromatic polyvalent carboxylic acid or an alicyclic polyvalent carboxylic acid, it is preferably 3 to 20 valent.

  The polyvalent carboxylic acid is represented by the following general formula (b).

Formula (b) R ₁₂ (COOH) _m1 (OH) _n1
In the formula, R ₁₂ represents an (m1 + n1) -valent organic group, m1 represents a positive integer of 2 or more, n1 represents an integer of 0 or more, a COOH group represents a carboxyl group, and an OH group represents an alcoholic or phenolic hydroxyl group.

  Examples of preferred polyvalent carboxylic acids include the following, but the present invention is not limited to these.

  Trivalent or higher aromatic polyvalent carboxylic acids such as trimellitic acid, trimesic acid, pyromellitic acid or derivatives thereof, succinic acid, adipic acid, azelaic acid, sebacic acid, oxalic acid, fumaric acid, maleic acid, tetrahydrophthal An aliphatic polyvalent carboxylic acid such as an acid, an oxypolyvalent carboxylic acid such as tartaric acid, tartronic acid, malic acid and citric acid can be preferably used. In particular, it is preferable to use an oxypolycarboxylic acid from the viewpoint of improving retention.

  There is no restriction | limiting in particular as alcohol used for the polyhydric carboxylic acid ester compound which can be used for this invention, Well-known alcohol and phenols can be used.

  For example, an aliphatic saturated alcohol or aliphatic unsaturated alcohol having a straight chain or a side chain having 1 to 32 carbon atoms can be preferably used. It is more preferable that it is C1-C20, and it is especially preferable that it is C1-C10.

  In addition, alicyclic alcohols such as cyclopentanol and cyclohexanol or derivatives thereof, aromatic alcohols such as benzyl alcohol and cinnamyl alcohol, or derivatives thereof can also be preferably used.

  When an oxypolycarboxylic acid is used as the polycarboxylic acid, the alcoholic or phenolic hydroxyl group of the oxypolycarboxylic acid may be esterified with a monocarboxylic acid. Examples of preferred monocarboxylic acids include the following, but the present invention is not limited thereto.

  As the aliphatic monocarboxylic acid, a fatty acid having a straight chain or a side chain having 1 to 32 carbon atoms can be preferably used. It is more preferable that it is C1-C20, and it is especially preferable that it is C1-C10.

  Preferred aliphatic monocarboxylic acids include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethyl-hexanecarboxylic acid, undecylic acid, lauric acid, tridecylic acid, Saturated fatty acids such as myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, melicic acid, and laccelic acid, undecylenic acid, olein Examples thereof include unsaturated fatty acids such as acid, sorbic acid, linoleic acid, linolenic acid, and arachidonic acid.

  Examples of preferred alicyclic monocarboxylic acids include cyclopentane carboxylic acid, cyclohexane carboxylic acid, cyclooctane carboxylic acid, or derivatives thereof.

  Examples of preferred aromatic monocarboxylic acids include those in which an alkyl group is introduced into the benzene ring of benzoic acid such as benzoic acid and toluic acid, and two or more benzene rings such as biphenyl carboxylic acid, naphthalene carboxylic acid, and tetralin carboxylic acid. The aromatic monocarboxylic acid which has, or those derivatives can be mentioned. Particularly preferred are acetic acid, propionic acid, and benzoic acid.

  The molecular weight of the polyvalent carboxylic acid ester compound is not particularly limited, but is preferably in the range of 300 to 1000, and more preferably in the range of 350 to 750. The larger one is preferable in terms of improvement in retention, and the smaller one is preferable in terms of moisture permeability and compatibility with cellulose acylate.

  The alcohol used for the polyvalent carboxylic acid ester that can be used in the present invention may be one kind or a mixture of two or more kinds.

  The acid value of the polyvalent carboxylic acid ester compound that can be used in the present invention is preferably 1 mgKOH / g or less, and more preferably 0.2 mgKOH / g or less. Setting the acid value in the above range is preferable because the environmental fluctuation of retardation is also suppressed.

  In addition, an acid value means the milligram number of potassium hydroxide required in order to neutralize the acid (carboxyl group which exists in a sample) contained in 1g of samples. The acid value is measured according to JIS K0070.

  Examples of particularly preferred polyvalent carboxylic acid ester compounds are shown below, but the present invention is not limited thereto.

  For example, triethyl citrate, tributyl citrate, acetyl triethyl citrate (ATEC), acetyl tributyl citrate (ATBC), benzoyl tributyl citrate, acetyl triphenyl citrate, acetyl tribenzyl citrate, dibutyl tartrate, diacetyl dibutyl tartrate, Examples include tributyl trimellitic acid and tetrabutyl pyromellitic acid.

  In the present invention, a deterioration inhibitor, a peeling accelerator, a matting agent, a lubricant and the like can be appropriately used as necessary.

(Deterioration inhibitor)
In the present invention, a known deterioration (oxidation) inhibitor such as 2,6-di-tert-butyl-4-methylphenol, 4,4'-thiobis- (6-tert-butyl-3) is added to the cellulose acylate solution. -Methylphenol), 1,1'-bis (4-hydroxyphenyl) cyclohexane, 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 2,5-di-tert-butylhydroquinone, pentaerythris A phenolic or hydroquinone antioxidant such as lithyl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] can be added. Further, tris (4-methoxy-3,5-diphenyl) phosphite, tris (nonylphenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, bis (2,6-di-tert) It is preferable to use a phosphorus-based antioxidant such as -butyl-4-methylphenyl) pentaerythritol diphosphite and bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite. The addition amount of the deterioration inhibitor is 0.05 to 5.0 parts by mass with respect to 100 parts by mass of the cellulose acylate.

(Peeling accelerator)
The cellulose acylate film according to the present invention preferably contains a release accelerator from the viewpoint of improving releasability. The peeling accelerator can be included at a ratio of 0.001 to 1% by mass, for example, and the addition of 0.5% by mass or less is preferable because separation of the release agent from the film hardly occurs. 005% by mass or more is preferable because a desired peeling reduction effect can be obtained. Therefore, it is preferably included at a rate of 0.005 to 0.5% by mass, and at a rate of 0.01 to 0.3% by mass. More preferably. As the peeling accelerator, known ones can be adopted, and organic and inorganic acidic compounds, surfactants, chelating agents and the like can be used. Among them, polyvalent carboxylic acids and esters thereof are effective, and in particular, ethyl esters of citric acid can be used effectively.

(Matting agent)
In particular, the cellulose acylate film according to the present invention is generally added with fine particles in order to prevent scratching or deterioration of transportability when handled. They are called matting agents, anti-blocking agents or anti-scratching agents and have been used conventionally. They are not particularly limited as long as they have the above-described functions, and may be an inorganic compound matting agent or an organic compound matting agent.

  Specific examples of the inorganic compound matting agent include silicon-containing inorganic compounds (for example, silicon dioxide, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, etc.), titanium oxide, and zinc oxide. , Aluminum oxide, barium oxide, zirconium oxide, strongtium oxide, antimony oxide, tin oxide, tin oxide / antimony, calcium carbonate, talc, clay, calcined kaolin, calcium phosphate, etc., more preferably silicon-containing inorganic compounds and oxides Although it is zirconium, since the turbidity of a cellulose acylate film can be reduced, silicon dioxide is particularly preferably used. As the silicon dioxide fine particles, for example, commercially available products having trade names such as Aerosil R972, R974, R812, 200, 300, R202, OX50, TT600 (manufactured by Nippon Aerosil Co., Ltd.) can be used. As the zirconium oxide fine particles, for example, those commercially available under trade names such as Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) can be used.

  Preferable specific examples of the organic compound matting agent include, for example, polymers such as silicone resin, fluorine resin and acrylic resin, and among them, silicone resin is preferably used. Of the silicone resins, those having a three-dimensional network structure are particularly preferable. A commercial product having a trade name can be used.

  When these matting agents are added to the cellulose acylate solution, the method is not particularly limited, and there is no problem as long as a desired cellulose acylate solution can be obtained by any method. For example, an additive may be contained at the stage of mixing cellulose acylate and a solvent, or an additive may be added after preparing a mixed solution with cellulose acylate and a solvent. Further, it may be added and mixed immediately before casting the dope, which is a so-called immediately preceding addition method, and the mixing is used by installing screw-type kneading online. Specifically, a static mixer such as an in-line mixer is preferable, and the in-line mixer is, for example, a static mixer SWJ (Toray static type in-pipe mixer Hi-Mixer) (manufactured by Toray Engineering). Is preferred. As for in-line addition, in order to eliminate density unevenness, particle aggregation, etc., Japanese Patent Application Laid-Open No. 2003-053752 adds an additive solution having a different composition to the main raw material dope in a method for producing a cellulose acylate film. There is described an invention in which the distance L between the nozzle tip and the starting end portion of the in-line mixer is 5 times or less of the main raw material pipe inner diameter d, thereby eliminating concentration unevenness, matting particles and the like. As a more preferred embodiment, the distance (L) between the tip opening of the additive liquid supply nozzle having a composition different from that of the main raw material dope and the starting end of the in-line mixer is 10 times or less the inner diameter (d) of the supply nozzle tip opening. And that the in-line mixer is a static unstirred in-tube mixer or a dynamic agitated in-tube mixer. More specifically, it is disclosed that the flow rate ratio of the cellulose acylate film main raw material dope / in-line additive solution is 10/1 to 500/1, preferably 50/1 to 200/1. Furthermore, the additive is also used in Japanese Patent Application Laid-Open No. 2003-014933, which aims at a retardation film with little additive bleed-out, no delamination phenomenon between layers, and excellent slipperiness and excellent transparency. As a method of addition, it may be added in a melting pot, or a solution in which additives or additives are dissolved or dispersed between the melting pot and a co-casting die may be added to the dope being fed. However, in the latter case, it is described that it is preferable to provide a mixing means such as a static mixer in order to improve the mixing property.

  The cellulose acylate film according to the present invention contains a matting agent to prevent scratching by reducing the coefficient of friction of the film surface, to prevent creaking that occurs when a wide film is wound long, and to prevent film breakage. It is preferable from the viewpoint.

  In the cellulose acylate film according to the present invention, if the matting agent is not added in a large amount, the haze of the film does not increase. When actually used in an LCD, inconveniences such as a decrease in contrast and generation of bright spots occur. Hateful. From these viewpoints, it is preferably included at a ratio of 0.01 to 5.0 mass%, more preferably included at a ratio of 0.03 to 3.0 mass%, and a ratio of 0.05 to 1.0 mass% It is particularly preferable to include

<Method for producing cellulose acylate film>
Next, a method for producing a cellulose acylate film according to the present invention will be described.

  The cellulose acylate film according to the present invention can be preferably used regardless of whether it is a film produced by a solution casting method or a film produced by a melt casting method.

  The cellulose acylate film according to the present invention is produced by the solution casting method, and at least the cellulose acylate according to the present invention, the ultraviolet absorber represented by the general formula (Ab), and, if necessary, a solvent as a solvent. Preparing a dope by dissolving it in a process, casting a dope onto an endless metal support that moves indefinitely, drying the cast dope as a web, peeling from the metal support, stretching or width It is performed by a holding step, a drying step, and a step of winding the finished film.

  The process for preparing the dope will be described. The concentration of cellulose acylate in the dope is preferably higher because the drying load after casting on the metal support can be reduced, but if the concentration of cellulose acylate is too high, the load during filtration increases and the filtration accuracy Becomes worse. As a density | concentration which makes these compatible, 10-35 mass% is preferable, More preferably, it is 15-25 mass%.

  It is preferable to add a specified amount of the compound represented by the general formula (I) to the dope preparation kettle.

  The solvent used in the dope may be used alone or in combination of two or more. However, it is preferable in terms of production efficiency that a good solvent and a poor solvent of cellulose acylate are mixed and used. A larger amount is preferable from the viewpoint of the solubility of cellulose acylate.

  The preferable range of the mixing ratio of the good solvent and the poor solvent is 70 to 98% by mass for the good solvent and 2 to 30% by mass for the poor solvent. With a good solvent and a poor solvent, what dissolve | melts the cellulose acylate to be used independently is defined as a good solvent, and what poorly swells or does not melt | dissolve is defined as a poor solvent.

  Therefore, the good solvent and the poor solvent change depending on the degree of acetyl substitution of cellulose acylate.

  Although the good solvent used for this invention is not specifically limited, Organic halogen compounds, such as a methylene chloride, dioxolanes, acetone, methyl acetate, methyl acetoacetate, etc. are mentioned. Particularly preferred is methylene chloride or methyl acetate.

  Moreover, although the poor solvent used for this invention is not specifically limited, For example, methanol, ethanol, n-butanol, cyclohexane, cyclohexanone, etc. are used preferably. Moreover, it is preferable that 0.01-2 mass% of water contains in dope.

  Moreover, the solvent used for melt | dissolution of a cellulose acylate collect | recovers the solvent removed from the film by drying at the film-forming process, and uses this again.

  The recovered solvent may contain trace amounts of additives added to cellulose acylate, such as plasticizers, UV absorbers, polymers, and monomer components. Can be purified and reused if necessary.

  As a method for dissolving cellulose acylate when preparing the dope described above, a general method can be used. When heating and pressurization are combined, it is possible to heat above the boiling point at normal pressure.

  It is preferable to stir and dissolve while heating at a temperature that is equal to or higher than the boiling point of the solvent at normal pressure and that the solvent does not boil under pressure, in order to prevent the generation of massive undissolved materials called gels and mamaco.

  Further, a method in which cellulose acylate is mixed with a poor solvent and wetted or swollen, and then a good solvent is added and dissolved is also preferably used.

  The pressurization may be performed by a method of injecting an inert gas such as nitrogen gas or a method of increasing the vapor pressure of the solvent by heating. Heating is preferably performed from the outside. For example, a jacket type is preferable because temperature control is easy.

  A higher heating temperature with the addition of a solvent is preferable from the viewpoint of the solubility of cellulose acylate, but if the heating temperature is too high, the required pressure increases and the productivity deteriorates.

  A preferable heating temperature is 45 to 120 ° C, more preferably 60 to 110 ° C, and still more preferably 70 ° C to 105 ° C. The pressure is adjusted so that the solvent does not boil at the set temperature.

  Alternatively, a cooling dissolution method is also preferably used, whereby cellulose acylate can be dissolved in a solvent such as methyl acetate.

  Next, this cellulose acylate solution is filtered using a suitable filter medium such as filter paper. As the filter medium, it is preferable that the absolute filtration accuracy is small in order to remove insoluble matters and the like, but there is a problem that the filter medium is easily clogged if the absolute filtration accuracy is too small.

  For this reason, a filter medium with an absolute filtration accuracy of 0.008 mm or less is preferable, a filter medium with 0.001 to 0.008 mm is more preferable, and a filter medium with 0.003 to 0.006 mm is still more preferable.

  There are no particular restrictions on the material of the filter medium, and ordinary filter media can be used. However, plastic filter media such as polypropylene and Teflon (registered trademark), and metal filter media such as stainless steel do not drop off fibers. preferable.

  It is preferable to remove and reduce impurities, particularly bright spot foreign matter, contained in the raw material cellulose acylate by filtration.

Bright spot foreign matter means that when two polarizing plates are placed in a crossed Nicol state, an optical film or the like is placed between them, light is applied from one polarizing plate side, and observation is performed from the other polarizing plate side. It is a point (foreign matter) where light from the opposite side appears to leak, and the number of bright spots having a diameter of 0.01 mm or more is preferably 200 / cm ² or less.

More preferably, it is 100 pieces / cm < ² > or less, More preferably, it is 50 pieces / m < ² > or less, More preferably, it is 0-10 pieces / cm < ² > or less. Further, it is preferable that the number of bright spots of 0.01 mm or less is small.

  The dope can be filtered by a normal method, but the method of filtering while heating at a temperature not lower than the boiling point of the solvent at normal pressure and in a range where the solvent does not boil under pressure is the filtration pressure before and after filtration. The increase in the difference (referred to as differential pressure) is small and preferable.

  A preferred temperature is 45 to 120 ° C, more preferably 45 to 70 ° C, and still more preferably 45 to 55 ° C.

  A smaller filtration pressure is preferred. The filtration pressure is preferably 1.6 MPa or less, more preferably 1.2 MPa or less, and further preferably 1.0 MPa or less.

  Here, the dope casting will be described.

  The metal support in the casting (casting) step preferably has a mirror-finished surface. As the metal support, a stainless steel belt or a drum whose surface is plated with a casting is preferably used.

  The cast width can be 1 to 4 m. The surface temperature of the metal support in the casting step is −50 ° C. to a temperature lower than the boiling point of the solvent, and a higher temperature is preferable because the web can be dried faster. May deteriorate.

  A preferable support temperature is 0 to 55 ° C, and more preferably 25 to 50 ° C. Alternatively, it is also a preferable method that the web is gelled by cooling and peeled from the drum in a state containing a large amount of residual solvent.

  The method for controlling the temperature of the metal support is not particularly limited, and there are a method of blowing hot air or cold air, and a method of contacting hot water with the back side of the metal support. It is preferable to use warm water because heat transfer is performed efficiently, so that the time until the temperature of the metal support becomes constant is short. When warm air is used, wind at a temperature higher than the target temperature may be used.

  In order for the cellulose acylate film to exhibit good flatness, the amount of residual solvent when peeling the web from the metal support is preferably 10 to 150% by mass, more preferably 20 to 40% by mass or 60 to 130% by mass. %, Particularly preferably 20 to 30% by mass or 70 to 120% by mass.

  In the present invention, the amount of residual solvent is defined by the following formula.

Residual solvent amount (% by mass) = {(MN) / N} × 100
M is the mass of a sample collected during or after the production of the web or film, and N is the mass after heating M at 115 ° C. for 1 hour.

  In the drying step of the cellulose acylate film, the web is peeled off from the metal support, and further dried, so that the residual solvent amount is preferably 1% by mass or less, more preferably 0.1% by mass or less. Particularly preferably, it is 0 to 0.01% by mass or less.

  In the film drying step, generally, a roll drying method (a method in which webs are alternately passed through a plurality of rolls arranged above and below) and a method in which the web is dried while being conveyed by a tenter method are employed.

  In order to produce the cellulose acylate film according to the present invention, it is particularly preferable to stretch in the width direction (lateral direction) by a tenter method in which both ends of the web are gripped with clips or the like. Peeling is preferably performed at a peeling tension of 300 N / m or less.

  The means for drying the web is not particularly limited, and can be generally performed with hot air, infrared rays, a heating roll, microwave, or the like, but it is preferably performed with hot air in terms of simplicity.

  The drying temperature in the web drying step is preferably increased stepwise from 40 to 200 ° C.

  The film thickness of the cellulose acylate film according to the present invention is preferably a thin film, a range of 10 to 100 μm is used, preferably 10 to 80 μm, more preferably 10 to 65 μm, and particularly preferably. 20-60 μm.

  The cellulose acylate film according to the present invention has a width of 1 to 4 m. In particular, those having a width of 1.5 to 3 m are preferably used, and particularly preferably 1.9 to 2.5 m. If it exceeds 4 m, conveyance becomes difficult.

  The cellulose acylate film according to the present invention has a retardation defined by the formula (i) in the in-plane direction from the viewpoint of taking advantage of high retardation development, although the required retardation is different depending on the required optical compensation effect. Ro is preferably 30 nm or more, more preferably in the range of 30 to 90 nm, and the thickness direction retardation Rth defined by formula (ii) is preferably 70 nm or more, and in the range of 70 to 300 nm. It is more preferable that

Formula (i) Ro = (nx−ny) × d
Formula (ii) Rth = {(nx + ny) / 2−nz} × d
(Where nx is the refractive index in the slow axis direction in the film plane, ny is the refractive index in the fast axis direction in the film plane, nz is the refractive index in the thickness direction of the film, and d is (The thickness of the film (nm).)
<Measurement of retardation Ro and Rth>
A 35 mm × 35 mm sample was cut out from the obtained film, conditioned at 25 ° C. and 55% RH for 2 hours, and measured with an automatic birefringence meter (KOBRA21DH, Oji Scientific Co., Ltd.) from the vertical direction at 590 nm and the film. It is calculated from the extrapolated value of the retardation value measured in the same manner while tilting the surface.

  A method for adjusting the phase difference is not particularly limited, but a method of adjusting by a stretching process is common.

  In order to obtain the target retardations Ro and Rth in the present invention, it is preferable that the cellulose acylate film has the structure of the present invention, and further the refractive index is controlled by controlling the transport tension and stretching.

  For example, the retardation can be changed by lowering or increasing the tension in the longitudinal direction.

  In addition, the retardation can be changed by biaxially or uniaxially stretching sequentially or simultaneously with respect to the longitudinal direction (film forming direction) of the film and the direction orthogonal to the film plane, that is, the width direction. .

  The draw ratios in the biaxial directions perpendicular to each other are preferably in the range of 0.8 to 1.5 times in the casting direction and 1.1 to 2.0 times in the width direction, respectively. More preferably, it is performed in the range of 0.8 to 1.1 times in the direction and 1.3 to 1.7 times in the width direction, and particularly preferably in the range of 1.3 to 1.5 times in the width direction. .

  The cellulose acylate film according to the present invention is easy to stretch and may easily develop retardation, and is highly resistant to process failures such as fracture.

  The stretching temperature is preferably 120 ° C. to 200 ° C., more preferably 150 ° C. to 200 ° C., and more preferably 150 ° C. to 190 ° C. or less.

  The residual solvent in the film is preferably 20 to 0%, more preferably 15 to 0%.

  Specifically, it is preferable that the residual solvent is stretched by 11% at 155 ° C., or the residual solvent is stretched by 2% at 155 ° C. Alternatively, it is preferable that the residual solvent is stretched at 11% at 160 ° C, or the residual solvent is stretched at less than 1% at 160 ° C.

  There is no particular limitation on the method of stretching the web. For example, a method in which a difference in peripheral speed is applied to a plurality of rolls, and the roll peripheral speed difference is used to stretch in the longitudinal direction, the both ends of the web are fixed with clips and pins, and the interval between the clips and pins is increased in the traveling direction. And a method of stretching in the vertical direction, a method of stretching in the horizontal direction and stretching in the horizontal direction, a method of stretching in the vertical and horizontal directions and stretching in both the vertical and horizontal directions. Of course, these methods may be used in combination.

  In the case of the so-called tenter method, driving the clip portion by the linear drive method is preferable because smooth stretching can be performed and the risk of breakage and the like can be reduced.

  These width maintenance or lateral stretching in the film forming step is preferably performed by a tenter, and may be a pin tenter or a clip tenter.

  When the slow axis or the fast axis of the cellulose acylate film according to the present invention is present in the film plane and the angle formed with the film forming direction is θ1, θ1 is preferably −1 ° or more and + 1 ° or less, It is more preferably −0.5 ° or more and + 0.5 ° or less.

  This θ1 can be defined as an orientation angle, and θ1 can be measured using an automatic birefringence meter KOBRA-21ADH (Oji Scientific Instruments). Each of θ1 satisfying the above relationship can contribute to obtaining high luminance in a display image, suppressing or preventing light leakage, and contributing to obtaining faithful color reproduction in a color liquid crystal display device.

<Physical properties of cellulose acylate film>
Moisture permeability of the cellulose acylate film according to the present invention, 40 ° C., preferably 300~1800g ^/ m 2 · 24h at 90% RH, preferably more ^{400~1500g / m 2 · 24h, 40~1300g} / m 2 · 24h is particularly preferred. The moisture permeability can be measured according to the method described in JIS Z 0208.

  The breaking elongation of the cellulose acylate film according to the present invention is preferably 10 to 80%, more preferably 20 to 50%.

  The visible light transmittance of the cellulose acylate film according to the present invention is preferably 90% or more, and more preferably 93% or more.

  The haze of the cellulose acylate film according to the invention is preferably less than 1%, particularly preferably 0 to 0.1%.

<Polarizing plate>
The protective film A according to the present invention can be used as an optical compensation film (also referred to as a retardation film) in a polarizing plate and a liquid crystal display device using the same.

  The polarizing plate is characterized in that it is a polarizing plate in which the protective film A according to the present invention is bonded to one surface of a polarizer. The liquid crystal display device of the present invention is characterized in that the polarizing plate according to the present invention is bonded to at least one liquid crystal cell surface via an adhesive layer.

  The polarizing plate can be produced by a general method. The polarizer side of the protective film A according to the present invention is subjected to alkali saponification treatment, and is bonded to at least one surface of a polarizer produced by immersing and stretching in an iodine solution using a completely saponified polyvinyl alcohol aqueous solution. Is preferred.

  The protective film B according to the present invention is bonded to the other surface. As the protective film B according to the present invention, a commercially available cellulose acylate film can also be used.

  For example, commercially available cellulose ester films (for example, Konica Minoltack KC8UX, KC5UX, KC8UCR3, KC8UCR4, KC8UCR5, KC8UY, KC4UY, KC4UE, KC8UE, KC8UY-HA, KC8UX-RWA, KC8UX-RHA, KC8UX-RHA, KC8UX KC4UXW-RHA-NC, manufactured by Konica Minolta Opto Co., Ltd.) is preferably used.

  In addition to the antiglare layer or the clear hard coat layer, the protective film B preferably used for the surface side or the backlight side of the display device includes an antireflection layer, an antistatic layer, an antifouling layer, a backcoat layer, and a light scattering layer. Etc. are preferable.

  A polarizer, which is a main component of a polarizing plate, is an element that allows only light of a plane of polarization in a certain direction to pass. A typical polarizer currently known is a polyvinyl alcohol-based polarizing film, which is polyvinyl alcohol. There are one in which iodine is dyed on a system film and one in which dichroic dye is dyed.

  For the polarizer, a polyvinyl alcohol aqueous solution is formed into a film and dyed by uniaxial stretching or dyed or uniaxially stretched and then preferably subjected to a durability treatment with a boron compound. The film thickness of the polarizer is preferably 5 to 30 μm, particularly preferably 10 to 20 μm.

  Further, the ethylene unit content described in JP-A-2003-248123, JP-A-2003-342322, etc. is 1 to 4 mol%, the degree of polymerization is 2000 to 4000, and the degree of saponification is 99.0 to 99.99 mol%. Ethylene-modified polyvinyl alcohol is also preferably used.

  Among them, an ethylene-modified polyvinyl alcohol film having a hot water cutting temperature of 66 to 73 ° C. is preferably used.

  A polarizer using this ethylene-modified polyvinyl alcohol film is excellent in polarization performance and durability, and has few color spots, and is preferably used for a large liquid crystal display device. In particular, the polarizing plate of the present invention in which the protective film B that does not contain an ultraviolet absorber is bonded to the polarizer can provide a polarizing plate having excellent overall durability because the polarizer itself is excellent in weather resistance and light resistance. It is done.

  The polarizer obtained as described above is usually used as a polarizing plate with a protective film bonded to both sides or one side thereof. Examples of the adhesive used for pasting include a PVA-based adhesive and a urethane-based adhesive. Among them, a PVA-based adhesive is preferably used.

<Liquid crystal display device>
By using the polarizing plate on which the protective film A and the protective film B according to the present invention are bonded to a liquid crystal display device, the liquid crystal display device of the present invention having various visibility can be manufactured.

  Since the protective film A according to the present invention has an optical compensation function, the protective film A side of the polarizing plate according to the present invention is bonded to at least one surface of the liquid crystal cell, and STN, TN, OCB, HAN, VA It is preferable to manufacture liquid crystal display devices of various driving methods such as (MVA, PVA), IPS, and OCB.

  A VA (MVA, PVA) type liquid crystal display device is preferable.

  By using the polarizing plate of the present invention, it is possible to obtain a liquid crystal display device having excellent visibility such as uneven coloring and front contrast, even with a large-screen liquid crystal display device having a size of 30 or more. It was.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

<Synthesis of cellulose acylate>
The cellulose acylates shown in Table 1 were synthesized by the methods described in JP-A-10-45804 and 08-231761, and the degree of substitution was measured. Specifically, sulfuric acid (7.8 parts by mass with respect to 100 parts by mass of cellulose) was added as a catalyst, and carvone as a raw material for the acyl substituent was added, and an acylation reaction was performed at 40 ° C. At this time, the kind and substitution degree of the acyl group were adjusted by adjusting the kind and amount of the carboxylic acid. In addition, aging was performed at 40 ° C. after acylation. Further, the low molecular weight component of the cellulose acylate was removed by washing with acetone.

  The degree of substitution was determined by the method specified in ASTM-D817-96.

<Ultraviolet absorber represented by general formula (Ab)>
As the ultraviolet absorber represented by the general formula (Ab), exemplary compounds were used as shown in Tables 2, 3, and 4, respectively.

<Preparation of protective film A101>
<Composition of main dope solution>
Methylene chloride 340 parts by mass Ethanol 64 parts by mass Cellulose acylate C (acetyl substitution degree 2.4) 100 parts by mass Ultraviolet absorber (UV agent 1-7) described in Table 2 4 parts by mass Retardation adjusting agent (Exemplary Compound I- 5) 4 parts by mass Plasticizer (Exemplary Compound B-3) 2.5 parts by mass The above was put into a closed container and dissolved while stirring to prepare a dope solution. Next, an endless belt casting apparatus was used to uniformly cast the dope solution on a stainless steel belt support at a temperature of 33 ° C. and a width of 1.5 m. The temperature of the stainless steel belt was controlled at 30 ° C.

  On the stainless steel belt support, the solvent was evaporated until the residual solvent amount in the cast (cast) film was 75%, and then peeled off from the stainless steel belt support with a peeling tension of 130 N / m.

  The peeled cellulose acylate film was stretched 1.5 times in the width direction using a tenter while applying heat at 160 ° C. The residual solvent at the start of stretching was 10%.

  Next, drying was terminated while the drying zone was conveyed by a number of rolls. The drying temperature was 130 ° C. and the transport tension was 100 N / m. Unnecessary parts on both sides of the film were cut.

  As described above, a protective film A101 having a dry film thickness of 40 μm, a width of 2.2 m, and a length of 3000 m was obtained.

<Production of protective films A102 to 159>
Protective films A102 to 159 were produced in the same manner as the protective film A101 except that the dope composition and production conditions were changed as shown in Tables 2, 3, and 4.

  In addition, when using the ultraviolet absorber together, both were mixed by 1: 1 by mass ratio.

  Moreover, the addition amount of an additive is described as "amount" in a table | surface, and each represents a mass part. In the (Remarks) column, (present invention) represents a sample according to the present invention, and the other samples were denoted as (comparative example).

<Preparation of protective film B101>
<Fine particle dispersion 1>
Fine particles (Aerosil R972V manufactured by Nippon Aerosil Co., Ltd.) 11 parts by weight Ethanol 89 parts by weight The above was stirred and mixed with a dissolver for 50 minutes, and then dispersed with Manton Gorin.

<Fine particle addition liquid 1>
The fine particle dispersion 1 was slowly added to the dissolution tank containing methylene chloride with sufficient stirring. Further, the particles were dispersed by an attritor so that the secondary particles had a predetermined particle size. This was filtered through Finemet NF manufactured by Nippon Seisen Co., Ltd. to prepare a fine particle additive solution 1.

Methylene chloride 99 parts by mass Fine particle dispersion 1 5 parts by mass A main dope solution having the following composition was prepared. First, methylene chloride and ethanol were added to the pressure dissolution tank. Triacetyl cellulose (acetyl substitution degree: 2.85, Mw 180000) was added to a pressurized dissolution tank containing a solvent while stirring. This is completely dissolved with heating and stirring. This was designated as Azumi Filter Paper No. The main dope solution was prepared by filtration using 244.

<Composition of main dope solution>
Methylene chloride 340 parts by mass Ethanol 64 parts by mass Triacetyl cellulose (acetyl substitution degree 2.85, Mw 180000)
100 parts by weight Plasticizer trimethylolpropane tribenzoate 5.5 parts by weight Plasticizer ethylphthalylethyl glycolate 5.5 parts by weight Particulate additive solution 1 1 part by weight A liquid was prepared. Next, an endless belt casting apparatus was used to uniformly cast the dope solution on a stainless steel belt support at a temperature of 33 ° C. and a width of 1.8 mm. The temperature of the stainless steel belt was controlled at 30 ° C.

  On the stainless steel belt support, the solvent was evaporated until the residual solvent amount in the cast (cast) film was 75%, and then peeled off from the stainless steel belt support with a peeling tension of 130 N / m.

  The peeled cellulose acetate film was stretched 1.15 times in the width direction using a tenter while applying heat at 160 ° C. The residual solvent at the start of stretching was 10%.

  Next, drying was terminated while the drying zone was conveyed by a number of rolls. The drying temperature was 130 ° C. and the transport tension was 100 N / m.

  As described above, a protective film B101 having a dry film thickness of 40 μm, a width of 2.2 m, and a length of 3000 m was obtained.

<Preparation of protective film B102>
A protective film B102 having a dry film thickness of 40 μm, a width of 2.2 m, and a length of 3000 m was obtained in the same manner except that 4 parts by mass of the ultraviolet absorber (UV agent 1-7) was added to the main dope liquid of the protective film B101. .

<Preparation of Polarizing Plate 101>
An ethylene-modified polyvinyl alcohol film having a hot water cutting temperature of 66 to 73 ° C. is uniaxially stretched (temperature 110 ° C., stretch ratio 5 times) in accordance with JP-A-2003-248123 to obtain a long roll film. It was.

  This was immersed in an aqueous solution composed of 0.075 g of iodine, 5 g of potassium iodide and 100 g of water for 60 seconds, and then immersed in an aqueous solution of 68 ° C. composed of 6 g of potassium iodide, 7.5 g of boric acid and 100 g of water. This was washed with water and dried to obtain a long roll-shaped polarizer.

  Subsequently, according to the following processes 1-5, the polarizing film 101 was produced by bonding the long roll-shaped polarizer, the protective film A101, and the protective film B101 on the back surface side.

  Step 1: The film was immersed in a 2 mol / L sodium hydroxide solution at 60 ° C. for 90 seconds, then washed with water and dried to obtain a protective film A101 and a protective film B101 saponified on the side to be bonded to the polarizer.

  Process 2: The said polarizer was immersed in the polyvinyl alcohol adhesive tank of 2 mass% of solid content for 1-2 seconds.

  Step 3: Excess adhesive adhered to the polarizer in Step 2 was gently wiped off, and this was placed between the protective film A101 and the protective film B101 treated in Step 1.

Step 4: The protective film A101 / polarizer / protective film B101 laminated in Step 3 was bonded at a pressure of 20 to 30 N / cm ² and a conveyance speed of about 2 m / min.

  Step 5: A sample obtained by bonding the protective film A101 / polarizer / protective film B101 produced in Step 4 in a drier at 80 ° C. by roll-to-roll was dried for 2 minutes to produce a polarizing plate 101.

<Preparation of Polarizing Plates 102 to 161>
Polarizing plates 102 to 161 were produced using combinations of the protective films shown in Tables 9 and 10 instead of the protective film A101 and the protective film B101.

<Production of liquid crystal display devices 101-161>
A liquid crystal panel for viewing angle measurement was produced as follows, and the characteristics as a liquid crystal display device were evaluated.

  Remove the polarizing plates on both sides of the VA mode type liquid crystal display device (Sony BRAVIAV1, 40-inch type) in advance, and the protective film A side of the polarizing plates 101 to 161 produced above is on the glass surface of the liquid crystal cell. It was pasted on both sides.

  In that case, it performed so that an absorption axis might turn to the same direction as the polarizing plate previously bonded, and produced the liquid crystal display devices 101-161, respectively.

<Evaluation>
(Measurement of retardation)
The prepared protective films A101 to 159 and the protective films B101 and 102 were conditioned for 5 hours or more in an environment of 23 ° C. and 55% RH, and then retardation values Ro and Rth were determined by the following formulas.

Ro = (nx−ny) × d
Rth = ((nx + ny) / 2−nz) × d
Here, d is the film thickness (nm), refractive index nx (refractive index in the slow axis direction), ny (refractive index in the direction perpendicular to the slow axis in the film plane), nz (in the thickness direction). The refractive index of the film).

  Retardation values (Ro) and (Rth) were determined using an automatic birefringence meter KOBRA-21ADH (Oji Scientific Instruments) at a wavelength of 590 nm in an environment of 23 ° C. and 55% RH.

  The results are shown in Tables 5, 6, and 7.

(Haze of wet heat durability test)
About the produced protective films A101 to 159, protective films B101 and 102, and polarizing plates 101 to 161, a difference in value from (total haze after exposure for 1000 hours at 60 ° C. and 90%) to (total haze before exposure) Was measured as the haze evaluation of the wet heat durability test. The haze was measured according to JIS K-7136 using a haze meter (NDH2000 type, manufactured by Nippon Denshoku Industries Co., Ltd.).
A: Difference is 0.1 or less B: Difference is 0.1-0.2
Δ: Difference is 0.2 to 0.5
X: Difference is 0.5 or more The results are shown in Tables 5, 6, 7, 8, and 9.

(Evaluation of front contrast after wet heat durability test)
The measurement was performed after the backlight of each liquid crystal display device was lit continuously for 1000 hours at 60 ° C. and 90%. For the measurement, EZ-Contrast 160D manufactured by ELDIM was used to measure the luminance in the normal direction of the display screen of white display and black display with a liquid crystal display device, and the ratio was defined as the front contrast. The evaluation of the front contrast before starting this test was ◎.
A: Front contrast is 5000 or more B: Front contrast is 4500 or more and less than 5000 Δ: Front contrast is 4000 or more and less than 4500 ×: Front contrast is less than 4000 The results are shown in Tables 8 and 9.

  As a result of the above evaluation, it was found that the polarizing plates 101 to 144 of the present invention were excellent in the haze of the wet heat durability test, and the liquid crystal display devices 101 to 144 of the present invention were excellent in the front contrast after the wet heat durability test.

  Moreover, the protective films A101 to 144 according to the present invention sufficiently exhibited retardation, and were excellent in visibility such as a viewing angle of the liquid crystal display device.

Claims (6)

In the polarizing plate in which both surfaces of the polarizer are sandwiched between the protective film A and the protective film B, the protective film A has a cellulose acylate with a total acyl substitution degree of 2.0 to 2.5 and a maximum absorption wavelength below 380 nm. It is a cellulose acylate film containing at least an ultraviolet absorber represented by the general formula (Ab), having an in-plane retardation Ro of 30 to 90 nm and a retardation Rth in the thickness direction of 70 to 300 nm. A polarizing plate characterized by that.

(R _{1 to} R ₆ represent a hydrogen atom, a halogen atom, and a substituent, and X and Y are substituents bonded to the benzene ring by a hydrogen atom, a halogen atom, or a hetero atom, and either X or Y Is a substituent bonded to the benzene ring by a heteroatom)   The polarizing plate according to claim 1, wherein the protective film A and the protective film B have a width of 1.9 to 2.5 m and a thickness of 10 to 65 μm.   The polarizing plate according to claim 1, wherein the protective film A contains a retardation adjusting agent and a plasticizer.   The polarizing plate according to any one of 1 to 3, wherein the protective film A is stretched.   The polarizing plate according to claim 1, wherein the protective film B is a cellulose acylate film that does not contain an ultraviolet absorber.   It is a liquid crystal display device which has the polarizing plate of any one of Claims 1-5, Comprising: The said protective film A is bonded by the liquid crystal cell surface, The liquid crystal display device characterized by the above-mentioned.