JP2008134624A - Polarizing plate protective film, polarizing plate and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polarizing plate protective film which not only avoids causing light leakage under conditions of high humidity or low humidity in a liquid crystal display device but also has excellent abrasion resistance and good adhesion of a hard coating layer, a polarizing plate and a liquid crystal display device each using the same. <P>SOLUTION: The polarizing plate protective film has a transparent substrate that is insoluble in a solvent having a dielectric constant of ≥10, a first easily-adhesive layer and the hard coating layer in this order. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polarizing plate protective film, a polarizing plate using the same, and a liquid crystal display device.

  As the polarizing plate protective film, triacetyl cellulose (TAC) is preferably used. A polarizing plate usually has a polarizer between two protective films. Since TAC permeates moisture to some extent, exposure to light for a long period of time, such as light leakage, cannot maintain display quality, and may be particularly noticeable in the TN mode.

  In recent years, when the TAC film is thinned in response to the demand for thinning the polarizing plate, moisture permeability may deteriorate or dimensional stability may deteriorate. In particular, with a TAC film of less than 40 μm, it is difficult to impart sufficient durability to the polarizing plate.

  An object of the present invention is to provide a polarizing plate protective film that does not cause light leakage at high or low humidity and has excellent scratch resistance in a liquid crystal display device, and a polarizing plate and a liquid crystal display device using the same. There is.

  The inventors of the present invention can form an adhesive layer between a protective film using a material that does not dissolve in a solvent having a dielectric constant of 10 or more and a hard coat layer in order to improve the adhesion. It has been found that the adhesion is particularly good when acrylic ester latex, methacrylic acid latex, and styrene latex are used for the easy-adhesion layer, leading to the present invention.

The present invention provides the following configurations.
1. A polarizing plate protective film having a transparent support having no solubility in a solvent having a dielectric constant of 10 or more, a first easy-adhesion layer, and a hard coat layer in this order.
2. 2. The polarizing plate protective film according to 1, wherein the transparent support is a cycloolefin-based film.
3. 3. The polarizing plate protective film according to 1 or 2, wherein the easy-adhesion layer contains at least one selected from acrylic ester latex, methacrylic latex, and styrene latex.
4). The polarizing plate protective film in any one of 1-3 in which the said hard-coat layer and / or the said easily bonding layer contain a ultraviolet absorber.
5. The polarizing plate protective film in any one of 1-4 in which the 2nd easily bonding layer is provided in the transparent support body surface on the opposite side to the surface which has a hard-coat layer.
6). The polarizing plate protective film according to any one of 1 to 5, further comprising an undercoat layer containing a hydrophilic polymer on the easy adhesion layer.
7). 6. The polarizing plate protective film according to 6, wherein the undercoat layer contains an ultraviolet absorber.
8). The polarizing plate which has a polarizer and the polarizing plate protective film in any one of 1-7.
9. 9. A liquid crystal display device, wherein at least one of the polarizing plates sandwiching the liquid crystal cell is the polarizing plate according to 8.

Specifically, the present invention provides the following configurations.
1. A polarizing plate protective film having a transparent support having no solubility in a solvent having a dielectric constant of 10 or more, a first easy-adhesion layer, and a hard coat layer in this order.
2. 2. The polarizing plate protective film according to 1, wherein the transparent support is a cycloolefin-based film.
3. 3. The polarizing plate protective film according to 1 or 2, wherein the easy-adhesion layer contains at least one selected from acrylic ester latex, methacrylic latex, and styrene latex.
4). The polarizing plate protective film in any one of 1-3 whose total haze is 10 to 80%.
5. The polarizing plate protective film in any one of 1-4 whose surface haze is 0.3 to 70%.
6). The polarizing plate protective film in any one of 1-5 whose internal haze is 10 to 80%.
7). The polarizing plate protective film according to any one of 1 to 6, wherein the polarizing plate protective film has a transmittance of 380 nm of 0 to 50% and a transmittance of 600 nm of 80 to 100%.
8). The polarizing plate protective film in any one of 1-7 whose moisture content of the said transparent support body is 1% or less.
9. The polarizing plate protective film in any one of 1-8 whose film thickness of the said transparent support body is 5-200 micrometers.
10. The polarizing plate protective film in any one of 1-9 whose glass transition temperature of the said transparent support body is 80 degreeC or more.
11. The polarizing plate protective film according to any one of 1 to 10, wherein at least one surface of the transparent support is subjected to corona discharge treatment.
12 The polarizing plate protective film according to any one of 1 to 11, wherein at least one surface of the transparent support is subjected to glow discharge treatment.
13. The polarizing plate protective film in any one of 1-12 with which the 2nd easily bonding layer is provided in the transparent support body surface on the opposite side to the surface which has a hard-coat layer.
14 The polarizing plate protective film in any one of 1-13 whose thickness of the said easily bonding layer is 50-1000 nm thickness.
15. The polarizing plate protective film in any one of 1-14 in which the said easily bonding layer contains a ultraviolet absorber.
16. The polarizing plate protective film according to any one of 1 to 15, wherein an undercoat layer containing a hydrophilic polymer is further formed on the easy adhesion layer.
17. 17. The polarizing plate protective film according to 16, wherein the undercoat layer has a thickness of 50 to 1000 nm.
18. The polarizing plate protective film according to 16 or 17, wherein the undercoat layer contains an ultraviolet absorber.
19. The polarizing plate protective film in any one of 1-18 in which the said easily bonding layer contains a conductive metal oxide.
20. The polarizing plate which has a polarizer and the polarizing plate protective film in any one of 1-19.
21. 21. The polarizing plate according to 20, wherein the other polarizing plate protective film sandwiching the polarizer has a film composed mainly of a cellulose ester film.
22. The polarizing plate according to 20 or 21, wherein the other polarizing plate protective film sandwiching the polarizer has a viewing angle compensation function.
23. The polarizing plate according to any one of 20 to 22, wherein the other polarizing plate protective film sandwiching the polarizer has an optically anisotropic layer.
24. 24. A liquid crystal display device, wherein at least one of the polarizing plates sandwiching the liquid crystal cell is a polarizing plate according to any one of 20 to 23.
25. The liquid crystal display device according to 24, further comprising a brightness enhancement film.
26. The liquid crystal display device according to 24 or 25, wherein the polarizing plate according to any one of 20 to 23 is installed only on the viewing side.
27. 27. The liquid crystal display device according to 26, wherein the brightness enhancement film and an adjacent polarizing plate protective film are in close contact.
28. 28. The liquid crystal display device according to any one of 24-27, wherein the display mode is a TN mode.

  The polarizing plate protective film of the present invention is such that in a liquid crystal display device having a polarizing plate using the same, light leakage at high or low humidity does not occur, scratch resistance is good, and adhesion is also good. It is something that can be done. The reason why such an excellent effect is achieved in the present invention is not clear, but by using a transparent support having a specific solubility, the moisture permeability of the polarizing plate is low and hardly affected by humidity change. And it is thought that it is because the adhesiveness of a transparent support body and a hard-coat layer improves remarkably by applying an easily bonding layer.

  Further, when the easy-adhesion layer is formed using an acrylate latex, a methacrylic acid latex, or a styrene latex, the easy-adhesion layer and / or the hard coat layer may contain an ultraviolet absorber. Since the ultraviolet absorber does not bleed out, durability is further improved. Bleed-out of the UV absorber occurs at the hard coat layer / support interface or the hard coat layer / air interface, and is improved by placing the above latex-based easy adhesion layer between the hard coat layer and the support. It was. The reason why such an effect can be obtained is not clear, but it is thought to be due to the good compatibility between the easily adhesive layer and the ultraviolet absorber.

Hereinafter, the present invention will be described in more detail.
The polarizing plate protective film of the present invention has an easy-adhesion layer and a hard coat on at least one surface of a transparent support that does not have solubility in a solvent having a dielectric constant of 10 or more (hereinafter sometimes simply referred to as “support”). Layers are provided in this order.
In the present invention, as described later, it is preferable that the hard coat layer and / or the easy adhesion layer contains an ultraviolet absorber.

[Overall configuration]
First, the layer structure of the polarizing plate protective film of the present invention will be described.
The polarizing plate protective film of the present invention is provided with an easy-adhesion layer and a hard coat layer on at least one of the transparent support.
Moreover, the aspect with which the easily bonding layer is provided in both surfaces of the said transparent support body is also preferable, and it is also preferable to provide a primer layer on an easily bonding agent layer.
Moreover, the other layer mentioned later can be provided suitably on or under the hard coat layer.

(Transparent support)
The support used in the present invention is a transparent support having no solubility in a solvent having a dielectric constant of 10 or more.
Here, the “dielectric constant” is measured by an impedance measurement method, and “does not have solubility in a solvent having a dielectric constant of 10 or more, preferably 10 to 80” means that the support is swollen by the solvent. It means not dissolving.
Examples of the solvent having a dielectric constant of 10 or more include methyl ethyl ketone, acetone, methyl isobutyl ketone, methyl acetate, ethyl acetate, butyl acetate, methanol, ethanol, isopropanol and the like.

  Examples of the transparent support as described above include a cycloolefin polymer support, a cycloolefin copolymer support, and a polynorbornene support.

Specifically, the transparent support is preferably a cycloolefin film. Examples of the cycloolefin-based film include a film produced from a polymer having an alicyclic structure.
A polymer containing an alicyclic structure has an alicyclic structure in the repeating unit of the polymer, a polymer containing an alicyclic structure in the main chain, and an alicyclic structure in the measurement chain. Any of the polymers containing can be used.
Examples of the alicyclic structure include a cycloalkane structure and a cycloalkene structure, and a cycloalkane structure is preferable from the viewpoint of thermal stability and the like. Although carbon number which comprises an alicyclic structure does not have a restriction | limiting in particular, Usually, 4-30 pieces, Preferably it is 5-20 pieces, More preferably, it is 5-15 pieces. When the number of carbon atoms constituting the alicyclic structure is in this range, heat resistance and flexibility are excellent.

  The proportion of the repeating unit having an alicyclic structure in the alicyclic structure-containing polymer may be appropriately selected within the range satisfying the above-mentioned solubility, but is usually 50% by mass or more, preferably 70% by mass or more, More preferably, it is 90 mass% or more. If the repeating unit having an alicyclic structure is 50% by mass or more, the heat resistance is preferably not lowered. In addition, repeating units other than the repeating unit which has an alicyclic structure in an alicyclic structure containing polymer are suitably selected according to the intended purpose.

  Specific examples of the alicyclic structure-containing polymer include (i) a norbornene polymer, (ii) a monocyclic olefin polymer, (iii) a cyclic conjugated diene polymer, and (iv) a vinyl alicyclic polymer. Examples include hydrocarbon polymers and their hydrides. Among these, norbornene-based polymers are preferable from the viewpoints of transparency and moldability.

Specific examples of the norbornene-based polymer include ring-opening polymers of norbornene-based monomers, ring-opening copolymers of norbornene-based monomers and other monomers capable of ring-opening polymerization, and these Examples thereof include hydrides, addition polymers of norbornene monomers, addition polymers with other monomers copolymerizable with norbornene monomers, and the like. Among these, from the viewpoint of transparency, a hydride of a ring-opening (co) polymer of a norbornene-based monomer is particularly preferable.
Examples of the norbornene-based monomer include bicyclo [2.2.1] hept-2-ene (common name: norbornene), tricyclo [4.3.0.1 ^2.5 ] deca-3,7-diene (conventional Name: cyclopentadiene), 7,8-benzotricyclo [4,3.0.1 ^2.5 ] dec-3-ene (common name: methanotetrahydrofluorene), tetracyclo [4.4.0.1 ^2.5 . 1 ^7.10 ] dodec-3-ene (common name: tetracyclododecene), and derivatives of these compounds, for example, those in which a substituent is introduced into the ring. Examples of the substituent include an alkyl group, an alkenyl group, an alkoxycarbonyl group, and a carboxyl group. In addition, these substituents may be the same or different and a plurality may be bonded to the ring. Norbornene monomers can be used alone or in combination of two or more.

  Other monomers capable of ring-opening polymerization with norbornene monomers include, for example, monocyclic olefins such as cyclohexene, cycloheptene, and cyclooctene and derivatives thereof; cyclic conjugated dienes such as cyclohexadiene and cycloheptadiene and the like. Derivatives; and the like.

  Ring-opening polymers of norbornene monomers and ring-opening copolymers of norbornene monomers and other monomers copolymerizable therewith are polymerized in the presence of a ring-opening polymerization catalyst. Can be obtained. Known ring-opening polymerization catalysts can be used.

  Other monomers that can be addition copolymerized with norbornene monomers include, for example, α-olefins having 2 to 20 carbon atoms such as ethylene and propylene, and derivatives thereof; cycloolefins such as cyclobutene and cyclopentene, and derivatives thereof. A non-conjugated diene such as 1,4-hexadiene; These monomers can be used alone or in combination of two or more. Among these, α-olefin is preferable, and ethylene is more preferable.

  The addition polymer of norbornene monomer and the addition copolymer of norbornene monomer and other monomer copolymerizable with it must be polymerized in the presence of an addition polymerization catalyst. Can be obtained. As the addition polymerization catalyst, a known catalyst can be used.

  A ring-opening polymer of a norbornene-based monomer, a hydride of a ring-opening copolymer of a norbornene-based monomer and another monomer capable of ring-opening polymerization, carbon-carbon using a known hydrogenation catalyst It is obtained by hydrogenating unsaturated bonds, preferably 90% or more.

  Examples of the norbornene-based polymer include, for example, trade names “ZEONOR” and “ZEONEX” manufactured by Nippon Zeon Co., Ltd .; trade names “ARTON” manufactured by JSR Corporation; trade names “OPTOREZ” manufactured by Hitachi Chemical Co., Ltd .; A commercial product such as a product name “APEL” can also be used.

(Ii) Examples of the monocyclic olefin polymer include addition polymers such as cyclohexene, cycloheptene, and cyclooctene.
Examples of (iii) cyclic conjugated diene polymers include polymers obtained by 1,2-addition polymerization or 1,4-addition polymerization of cyclic conjugated diene monomers such as cyclopentadiene and cyclohexadiene. be able to.

(Iv) The vinyl alicyclic hydrocarbon polymer is a polymer having a repeating unit derived from vinylcycloalkane or vinylcycloalkene. Examples of the vinyl alicyclic hydrocarbon polymer include a polymer of a vinyl alicyclic hydrocarbon compound such as vinyl cyclohexane; a polymer of a vinyl aromatic hydrocarbon compound such as styrene and α-methyl styrene. A hydride etc. are mentioned. The vinyl alicyclic hydrocarbon polymer is a random copolymer of a vinyl alicyclic hydrocarbon compound or a vinyl aromatic hydrocarbon compound and another monomer copolymerizable with these monomers, A copolymer such as a block copolymer may be used.
Examples of the hydride of (i) norbornene polymer, (ii) monocyclic olefin polymer, (iii) cyclic conjugated diene polymer, and (iv) vinyl alicyclic hydrocarbon polymer are described above. Examples include polymers in which hydrogen is added to unsaturated groups in each polymer.

  Preferred polymers for the present invention are addition (co) polymer cyclic polyolefins containing at least one repeating unit represented by the following general formula (II) and, if necessary, at least one repeating unit represented by the general formula (I) An addition (co) polymer cyclic polyolefin further comprising one. Further, a ring-opening (co) polymer containing at least one cyclic repeating unit represented by the general formula (III) can also be suitably used.

Formula (I)

Formula (II)

Formula (III)

In general formula (I), (II), and (III), m represents the integer of 0-4. R ¹ to R ⁶ represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, X ¹ to X ³ and Y ¹ to Y ³ represents a hydrogen atom, a hydrocarbon group having 1 to 10 carbon atoms, a halogen atom, a halogen substituted hydrocarbon group having 1 to 10 carbon atoms in the ^{_{atoms, - (CH 2) nCOOR 11}} , - (CH 2) nOCOR 12, - (CH 2) nNCO, - (CH 2) nNO 2, - (CH 2 _{) nCN, - (CH 2)} nCONR 13 R 14, - (CH 2) nNR 13 R 14, - (CH 2) nOZ, - (CH 2) nW or X ¹ and Y ^1, X ² and Y ^2,, Alternatively, it represents (—CO) ₂ O or (—CO) ₂ NR ¹⁵ composed of X ³ and Y ³ . R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , and R ¹⁵ represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, Z represents a hydrocarbon group or a hydrocarbon group substituted with a halogen, W represents SiR ¹⁶ pD _3-p , (R ¹⁶ represents a hydrocarbon group having 1 to 10 carbon atoms, D represents a halogen atom, —OCOR ¹⁶ or —OR ¹⁶ , and p represents an integer of 0 to 3; N) represents an integer of 0 to 10.

  The molecular weight of the polymer having the alicyclic structure is a polyisoprene or polystyrene equivalent weight average molecular weight measured by gel permeation chromatography using cyclohexane (toluene when the polymer resin is not dissolved) as a solvent. Is usually in the range of 10,000 to 300,000, preferably 20,000 to 200,000. When the molecular weight is in such a range, the mechanical strength and molding processability of the transparent support are highly balanced and suitable.

  The glass transition temperature of the polymer having the alicyclic structure may be appropriately selected depending on the purpose of use, but is preferably 80 ° C or higher, more preferably in the range of 100 ° C to 250 ° C. When the glass transition temperature is in such a range, the transparent support is excellent in durability without causing deformation or stress in use at high temperatures.

The support produced using the polymer having the alicyclic structure can be obtained by molding the polymer into a film by a known molding method.
Examples of the method for forming into a film include a solution casting method and a melt extrusion method. Among these, the melt extrusion molding method is preferable from the viewpoint of reducing the content of volatile components and the thickness unevenness in the film and the productivity. Further, examples of the melt extrusion molding method include a method using a die such as a T die and an inflation method, but a method using a T die is preferable in terms of excellent thickness accuracy.
When a method using a T die is employed as a method for forming a film, the melting temperature in an extruder having a T die is preferably 80 to 180 ° C. higher than the glass transition temperature of the polymer used. It is more preferable to set the temperature to be higher by 150 ° C. If the melting temperature in the extruder is excessively low, the fluidity of the polymer is lowered. Conversely, if the melting temperature is excessively high, the polymer may be deteriorated.

  Furthermore, it is preferable to pre-dry the polymer to be used before forming into a film. For example, the preliminary drying is performed using a hot air dryer in the form of pellets. The drying temperature is preferably 100 ° C. or more, and the drying time is preferably 2 hours or more. By performing preliminary drying, the amount of volatile components in the film can be reduced. Furthermore, foaming of the extruded polymer can be prevented.

  The polymer to be used preferably has a saturated water absorption of less than 0.05%. By using a material having a saturated water absorption of less than 0.05%, moisture is released when forming a laminate on a film, so that quality is not deteriorated and productivity is not lowered. Further, the film does not expand and contract due to moisture absorption, and the laminated layer does not peel from the transparent plastic film. In particular, when used in a large-screen liquid crystal display device, it is possible to eliminate image quality deterioration caused by dimensional changes due to moisture absorption.

  In the present invention, the polymer having an alicyclic structure used for a cycloolefin-based film preferably has a glass transition temperature (Tg) of 80 ° C. or higher, more preferably 90 ° C. or higher. If it is less than 80 degreeC, the dimensional stability of the obtained film under high temperature and high humidity may be inferior. Tg was determined from the tan δ peak measured by dynamic viscoelasticity.

  The above-mentioned cycloolefin-based film can be provided with slipperiness as required. The slipperiness imparting means is not particularly limited, but is an external particle addition method in which inert inorganic particles are added to cycloolefin, an internal particle precipitation method in which a catalyst to be added at the time of cycloolefin synthesis, or a surfactant, etc. Generally, a method of coating the film surface is used.

  In the production of the film, functional layers such as an antistatic layer, a slippery layer, an adhesive layer, and a barrier layer may be coated before and / or after stretching. At this time, various surface treatments such as corona discharge treatment, atmospheric pressure plasma treatment, and chemical treatment can be performed as necessary.

  Hereinafter, the physical properties of the transparent support used in the present invention will be described.

(Film thickness)
The thickness of the transparent support is 5 to 200 μm, preferably 5 to 100 μm, and more preferably 40 to 100 μm.

(Moisture permeability)
The moisture permeability of the transparent support is preferably 700 g / m ² · day or less, more preferably 300 g / m ² · day or less, and most preferably 100 g / m ² · day or less.
Due to the low moisture permeability, when processed into a polarizing plate and used in a liquid crystal display device, problems such as light leakage and a decrease in the degree of polarization hardly occur even in a high and low humidity environment.

(Elastic modulus)
The elastic modulus of the transparent support is preferably 3 to 7 GPa.
When the elastic modulus is within this range, when processed into a polarizing plate and used in a liquid crystal display device, problems such as light leakage and a decrease in the degree of polarization hardly occur even in a high and low humidity environment.

(Moisture content)
The water content of the transparent support is preferably 1% or less.
When the moisture content is within this range, when processed into a polarizing plate and used in a liquid crystal display device, problems such as light leakage and a decrease in the degree of polarization hardly occur even in a high humidity and low humidity environment.

  The transparent support may be a single (single layer) film made of the cycloolefin film, but includes at least one layer made of the cycloolefin film as long as the effects of the present invention are not impaired. It is good also as a multilayer film which consists of these resin layers. When the cycloolefin layer is A and the other resin layers are B and C, for example, A / B, A / B / A, B / A / B, and B / A / C can be configured. Of course, it is possible to have a structure of four or more layers. By adopting such a multilayer structure, for example, a plurality of functions can be simultaneously imparted by laminating a film having high strength and water barrier properties on the core layer and the outer layer.

  In addition, when adding fine particles such as a matting agent in order to impart slipperiness, an effect can be obtained if it is added only to the outermost layer, so that a function can be imparted without degrading transparency and the like.

(Fine particles that can be added)
The fine particles that can be added are not particularly limited, and examples thereof include inorganic compound fine particles and organic compound fine particles.

  Inorganic compounds include silicon-containing compounds, silicon dioxide, aluminum oxide, zirconium oxide, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate, etc. More preferred are inorganic compounds containing silicon and zirconium oxide, with silicon dioxide being particularly preferred.

  As the silicon dioxide fine particles, for example, commercially available products such as Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600 (manufactured by Nippon Aerosil Co., Ltd.) can be used.

  As the fine particles of zirconium oxide, for example, commercially available products such as Aerosil R976 and R811 (manufactured by Nippon Aerosil Co., Ltd.) can be used.

  As the organic compound, for example, polymers such as silicone resin, fluorine resin and acrylic resin are preferable, and among them, silicone resin is preferably used.

  Among the above-described silicone resins, those having a three-dimensional network structure are particularly preferable. For example, Tospearl 103, 105, 108, 120, 145, 3120 and 240 (manufactured by Toshiba Silicone) are used. A commercial product having the trade name of can be used.

In the polarizing plate protective film of the present invention, the adhesion can be improved by performing corona discharge treatment or glow discharge treatment on at least one surface of the transparent support. It is preferable to laminate the following easy-adhesion layer after performing corona discharge treatment and glow discharge treatment, since the adhesion between the hard coat layer and the transparent support is further improved.
As the corona discharge treatment and the glow discharge treatment, generally known methods can be used without particular limitation.

[Easily adhesive layer]
The easy-adhesion layer is provided between the transparent support and the hard coat layer in at least one of the transparent supports.
The easy adhesion layer is a layer provided to improve the adhesion between the transparent support and the hard coat layer. The material for forming the easy adhesion layer is not particularly limited as long as it improves the adhesion between the hard coat layer and a transparent support formed of a cycloolefin film or the like.
As the easily adhesive layer, a layer containing a urethane polymer, a silicone layer containing a silicone compound having a reactive functional group, a layer containing an olefin resin, a layer made of an ester latex, a methacrylic acid latex, a styrene latex, or the like is preferable. . Furthermore, it is preferable to form an easy-adhesion layer composed of a layer containing an olefin resin, an ester latex, a methacrylic acid latex, and a styrene latex. In particular, the easy-adhesion layer is preferably a layer formed using at least one selected from acrylic ester latex, methacrylic acid latex, and styrene latex.

  First, olefin-based resins, silicone-based and latex-based materials that can be preferably used for the material for forming the easy-adhesion layer will be described.

<Olefin resin>
An olefin resin can be suitably used as a material for forming the easy adhesion layer. The olefin resin is not particularly limited, and may be a polymer made of a compound having an olefin double bond including carbon, hydrogen, oxygen, and nitrogen. For example, ethylene, propylene, butene, butadiene, styrene and the like can be mentioned. These may be homopolymerized or two or more types of copolymers. In particular, when a compound having a high polarity such as a hydroxyl group, a carboxyl group, an amino group, an isocyanate group, a nitro group, or a carbonyl group is used for the side chain or terminal, the substrate and the hard coat layer exhibit high adhesion. The easy-adhesion layer comprising the olefin resin of the present invention can be prepared by dissolving in an appropriate solvent using an appropriate mixing device such as a homomixer.

  The solvent is not particularly limited, and ketones such as methyl ethyl ketone, acetone and methyl isobutyl ketone, esters such as methyl acetate, ethyl acetate and butyl acetate, aromatic compounds such as toluene and xylene, diethyl ether, tetrahydrofuran and the like Examples include ethers, alcohols such as methanol, ethanol, and isopropanol. Cycloolefin films such as aromatic solvents such as toluene and xylene, chlorine solvents such as dichloromethane and carbon tetrachloride, hydrocarbon solvents such as n-hexane and cyclohexane, ketone solvents such as cyclohexanone and methyl isobutyl ketone When a solvent that dissolves and swells is used, the interaction with the cycloolefin-based film becomes stronger, so that higher adhesion can be obtained, and further, the interlayer boundary becomes ambiguous, so that interference fringes are likely to disappear. The concentration is, for example, about 5 to 70% with respect to the solid content.

  In the present invention, the easy-adhesion layer made of an olefin-based resin can be applied to a cycloolefin-based film by, for example, a conventional coating method such as slot coater, spin coater, roll coater, curtain coater, or screen printing. it can.

  The film thickness of the easy-adhesion layer made of an olefin resin in the present invention is preferably 0.05 to 10 μm, and if it is less than 0.05 μm, sufficient adhesion cannot be obtained, and if it exceeds 10 μm, the hard coat function is remarkably deteriorated. This is to make it happen. More preferably, it is 0.1-5 micrometers, More preferably, it is 0.5-2.0 micrometers. At this time, high adhesion and surface hardness can be obtained.

<Silicone type>
Another preferred example of the easy adhesion layer is an easy adhesion layer containing a silicone compound having a reactive functional group. Examples of the silicone compound having a reactive functional group preferably used for the easy-adhesion layer include, for example, an isocyanate group-containing alkoxysilanol compound, an amino group-containing alkoxysilanol compound, a mercapto group-containing alkoxysilanol compound, a carboxy group-containing alkoxysilanol compound, and an epoxy. Examples thereof include a group-containing alkoxysilanol compound, a vinyl type unsaturated group-containing alkoxysilanol compound, and a halogen group-containing alkoxysilanol compound. Of these various alkoxysilanol compounds, amino group-containing alkoxysilanol compounds are preferred.

Moreover, the other additive may be added to the silicone compound which has the said reactive functional group. Examples of the additive include tackifiers such as terpene resin, phenol resin, terpene-phenol resin, rosin resin, and xylene resin, and stabilizers such as antioxidant and heat stabilizer.
In addition, the surface of the film containing a cycloolefin resin includes a silicone resin having a reactive functional group and a film containing a cycloolefin resin by performing surface treatment such as corona treatment, plasma treatment, and low UV treatment in advance. Adhesion with the silicone layer is improved.

Furthermore, a titanium-based or tin-based catalyst for increasing the reactivity of the silicone compound having the reactive functional group may be added to the silicone compound having the reactive functional group.
By adding the catalyst, adhesion between the hard coat layer and the film containing the cycloolefin resin can be strengthened.

The silicone compound having the reactive functional group is coated and dried on the surface of a film containing a cycloolefin resin by a known method to form a silicone layer.
In coating, the silicone compound having the reactive functional group can be diluted with a solvent and used. The solvent is not particularly limited, and examples of the solvent include alcohol solvents such as isopropyl alcohol, ethanol, methanol, and butanol.

  When the silicone compound is included, the thickness of the easy-adhesion layer is usually 1 to 100 nm after drying, and preferably 10 to 50 nm. If the thickness of the silicone layer is in the range of 1 to 100 nm, the transparency of the polarizing plate protective film is not lowered while maintaining good adhesion, and therefore it is preferably within this range.

<Latex system>
As another preferred example of the easy-adhesion layer, an easy-adhesion layer composed of at least one of acrylic ester latex, methacrylic acid latex, and styrene latex can be formed. That is, in this invention, an easily bonding layer can be formed using these (co) polymer latex. When a latex-based easy-adhesion layer is used, when an ultraviolet absorber is used for the hard coat layer and / or the easy-adhesion layer, bleeding out of the ultraviolet absorber hardly occurs, which is preferable.
In addition, these latexes include (a) diolefin monomers, (b) vinyl monomers, (c) two or more vinyl groups, acryloyl groups, methacryloyl or allyl groups in one or more molecules. (D) an α-methylstyrene dimer and another polymerization chain transfer agent, and obtained by emulsion polymerization in an aqueous medium in the presence of the polymerization chain transfer agent. Copolymer latex may be used.

  Examples of the (a) diolefin monomer as one monomer forming the copolymer include conjugated dienes such as butadiene, isoprene and chloroprene, and butadiene is particularly preferably used.

  As the vinyl monomer (b) which is the second component of the copolymer used in the present invention, any monomer inherent to a vinyl group may be used, but preferably the following, styrene, acrylonitrile, Methyl methacrylate, vinyl chloride, vinyl acetate and their derivatives, alkyl esters of acrylic acid, acrylamide, methacrylamide, acrolein, methacrolein, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, allyl acrylate , Allyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, vinyl isocyanate, allyl isocyanate, and the like. Among them, acrylic acid is used in the present invention. Ester, methacrylic acid ester, or preferably contains styrene or a styrene derivative as a main component.

  Examples of the styrene derivatives include methyl styrene, dimethyl styrene, ethyl styrene, diethyl styrene, isopropyl styrene, butyl styrene, hexyl styrene, cyclohexyl styrene, decyl styrene, benzyl styrene, chloromel styrene, trifluoromethyl styrene, and ethoxymethyl. Styrene, acetoxymethylstyrene, methoxystyrene, 4-methoxy-3-methylstyrene, dimethoxystyrene, chlorostyrene, dichlorostyrene, trichlorostyrene, tetrachlorostyrene, pentachlorostyrene, bromostyrene, dibromostyrene, iodostyrene, fluoro Styrene, trifluorostyrene, 2-bromo-4-trifluoromethylstyrene, 4-fluoro-3-trifluoromethylstyrene, It can be exemplified sulfonyl benzoic acid methyl ester.

  Among the acrylic esters, preferred are alkyl acrylates, glycidyl (meth) acrylate, and 2-hydroxyethyl (meth) acrylate.

  The monomer (c), which is the third component of the copolymer used in the present invention, has two or more vinyl groups, acryloyl groups, methacryloyl groups, and allyl groups in the molecule. When polymerizing ordinary vinyl monomers such as 5-hexadiene-3-yne, hexatriene, divinyl ether, divinyl sulfone, diallyl phthalate, diallyl carbinol, diethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane dimethacrylate The so-called cross-linking agent added to can be mentioned.

  It is preferable that the content of the (a) diolephine monomer in the copolymer of the present invention is 10 to 60% by mass, particularly 15 to 40% by mass, based on the entire copolymer. (B) Although it is 90-40 mass% of the whole as a vinyl monomer, it is preferable that the said vinyl monomer is especially 70-40 mass% of the whole copolymerization. (C) The monomer having two or more vinyl groups, acryloyl groups, methacryloyl groups, and allyl groups in the molecule is 0 with respect to the total of (a) diolephine monomer and (b) vinyl monomer. 0.01 to 10% by mass, particularly 0.1 to 5% by mass is preferable.

  (D) The α-methylstyrene dimer in the polymerization chain transfer agent includes (a) 2--4-diphenyl-4-methyl-1-pentene and (b) 2-4-diphenyl-4-methyl as isomers. 2-pentene, (c) 1-1-3-trimethyl-3-phenylindane. The composition preferred as the α-methylstyrene dimer is that (a) component is 40% by mass or more, (b) component and / or (c) component is 60% by mass or less, more preferably (b) component is 50% by mass or more, The component (b) and / or the component (c) is 50% by mass or less, particularly preferably the component (a) is 70% by mass or more, and the component (b) and / or the component (c) is 30% by mass or less. (I) The chain transfer effect is excellent as the composition ratio of the component increases.

  The α-methylstyrene dimer is an impurity such as unreacted α-methylstyrene, α-methylstyrene oligomers other than the components (a), (b), and (c), as long as the object of the present invention is not impaired. An α-methylstyrene polymer may be included. When α-methylstyrene dimer is used, it can be used in an unpurified state after synthesizing α-methylstyrene dimer as long as the purpose is not impaired.

  (D) The ratio of α-methylstyrene dimer in the polymerization chain transfer agent is 2 to 100% by mass, preferably 3 to 100% by mass, and more preferably 5 to 95% by mass of the entire polymerization chain transfer agent. When the proportion of this α-methylstyrene dimer is 2% by mass or more, a copolymer latex excellent in adhesive strength and blocking resistance can be obtained. Moreover, the reactivity at the time of superposition | polymerization can be improved by combined use with (alpha) -methylstyrene dimer and another polymerization chain transfer agent.

  (D) The usage-amount of a polymerization chain transfer agent is 0.3-10 mass parts per 100 mass parts of monomer mixtures, Preferably it is 0.5-7 mass parts. When the amount of the (d) polymerization chain transfer agent used is 0.3 parts by mass or more, the blocking resistance is not inferior. On the other hand, when it is 10 parts by mass or less, the adhesive strength does not decrease, which is preferable. In addition, about the usage-amount of (alpha) -methylstyrene dimer, it is preferable to use in the range of 0.1-5 mass parts per 100 mass parts of monomer mixtures.

  Next, as the other chain transfer agent used in combination with the α-methylstyrene dimer in (d) the polymerization chain transfer agent, a known polymerization chain transfer agent used in general emulsion polymerization can be used. Specifically, for example, mercaptans such as octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan, t-tetradecyl mercaptan; dimethylxanthogen disulfide, diethylxanthogen disulfide, Xanthogen disulfides such as diisopropylxanthogen disulfide; thiuram disulfides such as tetramethylthiuram disulfide, tetraethylthiuram disulfide and tetrabutylthiuram disulfide; halogenated hydrocarbons such as carbon tetrachloride and ethylene bromide; hydrocarbons such as pentaphenylethane Acrolein, methacrolein, allyl alcohol, 2-ethylhexyl thioglycolate, terpinole , Α- terpinene, γ- terpinene, and the like can be given dipentene. These may be used alone or in combination of two or more. Of these, mercaptans, xanthogen disulfides, thiuram disulfides, carbon tetrachloride and the like are preferably used.

  The copolymer latex in the present invention can be produced by a conventionally known emulsion polymerization method except that the monomer mixture and the polymerization chain transfer agent are used. That is, it can be obtained by carrying out emulsion polymerization by adding a monomer mixture, a polymerization initiator, an emulsifier, a polymerization chain transfer agent and the like to an aqueous medium such as water. The solid content of the latex is preferably 3% by mass to 15% by mass.

  50-1000 nm is preferable, as for the thickness of the easily bonding layer formed by apply | coating said copolymer latex, 50-300 nm is more preferable, More preferably, it is 50 nm-200 nm.

  In the present invention, it is preferable to use a chloro-s-triazine-based crosslinking agent in combination with the copolymer latex. The combined use of dichloro-s-triazine-based cross-linking agent significantly improves the adhesive force under normal humidity conditions, high humidity conditions, and low humidity conditions, and no cracks occur under low humidity conditions. In addition, excellent effects such as antistatic properties, scratch resistance, water resistance, and solvent resistance can be imparted.

  In the present invention, as the dichloro-s-triazine-based crosslinking agent, it is preferable to use a compound represented by the following general formula (2) and / or a compound represented by the following general formula (3).

General formula (2)

  (In general formula (2), A represents an alkyl group, a cyclic alkyl group, an aryl group, an aralkyl group, a metal atom, or a hydrogen atom.)

General formula (3)

(In the general formula (3), R ¹ and R ² are each independently hydrogen, alkyl group, cyclic alkyl group, aryl group, aralkyl group, —NHR ³ (R ³ is alkyl group, acyl group), R ¹ and R ² may be bonded to each other and may form a 5- to 6-membered ring containing O, S, and N—R ⁴ (R ⁴ is an alkyl group).

  These dichloro-s-triazine crosslinking agents can be added in an amount of 0.1 to 100 parts by mass with respect to the monomer mixture. If the addition amount of the dichloro-s-triazine-based crosslinking agent is 0.1 parts by mass or more, in terms of improving the adhesive strength, the crack prevention effect, antistatic property, scratch resistance and water resistance under low humidity conditions are also included. There is no problem in terms of effects such as solvent resistance. On the other hand, if the addition amount of the dichloro-s-triazine-based crosslinking agent is 100 parts by mass or less, the emulsion or back is caused by a large amount of unreacted crosslinking agent remaining and moving to the upper gelatin layer to form a hardened film. It is preferable because the adhesiveness with the layer does not deteriorate.

  Specific examples of these dichloro-s-triazine-based crosslinking agents include the following.

The easy-adhesion layer can further contain an ultraviolet absorber.
From the viewpoint of excellent UV absorption and good liquid crystal display properties, the UV absorber has a transmittance of 0 to 50 nm at a wavelength of 380 nm in the entire polarizing plate protective film after the UV absorber is added to each layer. %, Preferably 0 to 30%, more preferably 0 to 10%, and the transmittance at 600 nm is 80 to 100%, preferably 85 to 100%, more preferably 90 to 100%. Specifically, it is the same as the ultraviolet absorber that can be used for the hard coat layer described later. Further, the amount used is preferably 1% by mass to 20% by mass in the solid content of the easy-adhesion layer, and more preferably 3% by mass to 15% by mass.

The easy-adhesion layer can contain a conductive metal oxide. Specifically, it is preferable to use conductive metal oxide particles that can be used for an antistatic layer described later.
The surface resistance of the adhesive layer is preferably from 10 ⁵ ~10 ¹² Ω / sq, more preferably from 10 ⁵ ~10 ⁹ Ω / sq, it is 10 ⁵ ~10 ⁸ Ω / sq Most preferred. The surface resistance of the antistatic layer can be measured by a four probe method.

  Moreover, an easily bonding layer can also be provided on both surfaces of the said transparent support body. That is, an easy-adhesion layer can be provided on the opposite side of the transparent support from which the hard coat layer is provided.

[Hard coat layer]
The hard coat layer is formed for the purpose of reducing the weak scratch resistance of the transparent support. Preferably, when antiglare property is imparted to the hard coat layer, reflection of the liquid crystal display device can be reduced.

  The refractive index of the hard coat layer in the present invention is preferably in the range of 1.48 to 2.00, more preferably 1.52 to 1, from the optical design for obtaining an antireflection film. .90, more preferably 1.55 to 1.80.

  For the purpose of controlling the refractive index of the hard coat layer, a high refractive index monomer, inorganic particles, or both can be added to the binder of the hard coat layer. In addition to the effect of controlling the refractive index, the inorganic particles also have the effect of suppressing cure shrinkage due to the crosslinking reaction. In the present invention, a polymer formed by polymerizing the polyfunctional monomer and / or the high refractive index monomer after the hard coat layer is formed, and the inorganic particles dispersed therein are referred to as a binder.

The hard coat layer is preferably formed using a resin formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound as a binder. For example, a coating composition containing an ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer is applied onto an easy-adhesion layer formed on a transparent support, and the polyfunctional monomer or polyfunctional oligomer is crosslinked or polymerized. It can be formed by reacting.
The functional group of the ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable.
Examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable.

The film thickness of the hard coat layer is usually about 0.5 μm to 50 μm, preferably 1 μm to 20 μm, more preferably 2 μm to 18 μm, most preferably 3 μm, from the viewpoint of imparting sufficient durability and impact resistance to the film. ~ 15 μm.
Further, the strength of the hard coat layer is preferably H or more, more preferably 2H or more, and most preferably 3H or more in a pencil hardness test.
Furthermore, in the Taber test according to JIS K5400, the smaller the wear amount of the test piece before and after the test, the better.

The haze of the hard coat layer varies depending on the function imparted to the polarizing plate protective film.
In the case where the sharpness of the image is maintained and the light scattering function is not imparted inside and on the surface of the hard coat layer, the haze value is preferably as low as possible, specifically 10% or less, more preferably 5% or less. Yes, most preferably 2% or less.

On the other hand, when the antiglare function is imparted by surface scattering of the hard coat layer, the total haze of the polarizing plate protective film of the present invention is preferably 3% to 80%, and more preferably 5% to 70%. . Moreover, it is preferable that the surface haze of the polarizing plate protective film of this invention is 0.3%-70%, and it is more preferable that it is 0.3%-20%. The internal haze (the value obtained by subtracting the surface haze value from the total haze value) of the polarizing plate protective film of the present invention is preferably 0% to 80%, more preferably 0% to 70%, and most preferably 0. % To 60%.
The film of the present invention can freely set surface haze and internal haze according to the purpose.

  In order to maintain the sharpness of the image, it is preferable to adjust the clarity of the transmitted image in addition to adjusting the uneven shape of the surface. The transparency of the polarizing plate protective film having no antiglare function is preferably 60% or more. The transmitted image clarity is generally an index indicating the degree of blurring of an image reflected through a film, and the larger this value, the clearer and better the image viewed through the film. The transmitted image definition is preferably 70% or more, and more preferably 80% or more.

<Granting antiglare properties>
As a method for forming anti-glare properties, a method of laminating and forming a mat-shaped shaping film having fine irregularities on the surface as described in JP-A-6-16851, described in JP-A-2000-206317. A method of forming by curing shrinkage of an ionizing radiation curable resin due to a difference in ionizing radiation dose, as described in JP 2000-338310 A, and a mass ratio of a good solvent to a translucent resin is reduced by drying. A method of forming unevenness on the surface of the coating film by solidifying the light-transmitting fine particles and the light-transmitting resin while gelling, and providing surface unevenness by external pressure as described in JP-A-2000-275404 The method of doing is known.

In the case of imparting antiglare properties to the hard coat layer, the composition containing a binder capable of imparting hard coat properties, translucent particles for imparting antiglare properties, and a solvent provides translucency. It is preferable that surface irregularities be formed by protrusions of the particles themselves or protrusions formed of an aggregate of a plurality of particles.
The hard coat layer having an antiglare function formed by dispersing the matte particles contains a binder and translucent particles dispersed in the binder. The antiglare layer having antiglare properties preferably has both antiglare properties and hard coat properties.
The polarizing plate protective film of this invention should just have either the hard-coat layer which has anti-glare property, and the hard-coat layer which does not have the above-mentioned anti-glare property, and may have both. Hereinafter, the hard coat layer having antiglare property may be referred to as “antiglare layer”.

[binder]
The antiglare layer can be formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound. That is, a coating composition containing an ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer as a binder is coated on a transparent support, and the polyfunctional monomer or polyfunctional oligomer is formed by a crosslinking reaction or a polymerization reaction. be able to.
The functional group of the ionizing radiation-curable polyfunctional monomer or polyfunctional oligomer is preferably a light, electron beam, or radiation polymerizable group, and among them, a photopolymerizable functional group is preferable.

Examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. Among them, a (meth) acryloyl group is preferable.
Specific examples of the photopolymerizable polyfunctional monomer having a photopolymerizable functional group include (meth) alkylene glycols such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, and propylene glycol di (meth) acrylate. Acrylic acid diesters; (Meth) acrylic acid of polyoxyalkylene glycols such as triethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate Diesters; (meth) acrylic acid diesters of polyhydric alcohols such as pentaerythritol di (meth) acrylate; 2,2-bis {4- (acryloxy-diethoxy) phenyl} propane, 2--2-bi {4- (acryloxy · polypropoxy) phenyl} ethylene or propylene oxide adduct (meth) acrylic acid diesters such as propane; and the like.
Furthermore, epoxy (meth) acrylates, urethane (meth) acrylates, and polyester (meth) acrylates are also preferably used as the photopolymerizable polyfunctional monomer.
Among these, esters of polyhydric alcohol and (meth) acrylic acid are preferable. More preferably, a polyfunctional monomer having 3 or more (meth) acryloyl groups in one molecule is preferable. Specifically, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, 1,2,4-cyclohexanetetra (meth) acrylate, pentaglycerol triacrylate, pentaerythritol tetra (meth) acrylate, penta Erythritol tri (meth) acrylate, (di) pentaerythritol triacrylate, (di) pentaerythritol pentaacrylate, (di) pentaerythritol tetra (meth) acrylate, (di) pentaerythritol hexa (meth) acrylate, tripentaerythritol triacrylate , Tripentaerythritol hexatriacrylate and the like.
In the present specification, “(meth) acrylate”, “(meth) acrylic acid”, and “(meth) acryloyl” represent “acrylate or methacrylate”, “acrylic acid or methacrylic acid”, and “acryloyl or methacryloyl”, respectively. .
As the monomer binder, monomers having different refractive indexes can be used in order to control the refractive index. Examples of particularly high refractive index monomers include bis (4-methacryloylthiophenyl) sulfide, vinyl naphthalene, vinyl phenyl sulfide, 4-methacryloxyphenyl-4′-methoxyphenyl thioether, and the like.
Further, for example, dendrimers described in JP-A-2005-76005 and JP-A-2005-36105, and norbornene ring-containing monomers as described in JP-A-2005-60425 can also be used.

Two or more polyfunctional monomers may be used in combination.
Polymerization of the monomer having an ethylenically unsaturated group can be performed by irradiation with ionizing radiation or heating in the presence of a photo radical initiator or a thermal radical initiator.
It is preferable to use a photopolymerization initiator for the polymerization reaction of the photopolymerizable polyfunctional monomer. As the photopolymerization initiator, a photoradical polymerization initiator and a photocationic polymerization initiator are preferable, and a photoradical polymerization initiator is particularly preferable.

<Photoinitiator>
Examples of photo radical polymerization initiators include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, anthraquinones, thioxanthones, azo compounds, peroxides (JP-A No. 2001-139663, etc.), 2, 3 -Dialkyldione compounds, disulfide compounds, fluoroamine compounds, aromatic sulfoniums, lophine dimers, onium salts, borate salts, active esters, active halogens, inorganic complexes, coumarins and the like.
Examples of acetophenones include 2,2-dimethoxyacetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxy-dimethylphenylketone, 1-hydroxy-dimethyl-p-isopropylphenylketone, 1-hydroxy Cyclohexyl phenyl ketone, 2-methyl-4-methylthio-2-morpholinopropiophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone, 4-phenoxydichloroacetophenone, 4-t- Butyl-dichloroacetophenone is included.
Examples of benzoins include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl dimethyl ketal, benzoin benzene sulfonate, benzoin toluene sulfonate, benzoin methyl ether, benzoin ethyl ether and benzoin isopropyl ether It is.
Examples of benzophenones include benzophenone, hydroxybenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, 2,4-dichlorobenzophenone, 4,4-dichlorobenzophenone and p-chlorobenzophenone, 4,4′-dimethylaminobenzophenone (Michler ketone), 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone and the like are included.
Examples of the borate salt are described in Japanese Patent Nos. 2764769 and 2002-116539, and in Kunz, Martin “Rad Tech '98. Proceeding April 19-22, 1998, Chicago”. And the organic borate compounds described. For example, the compounds described in JP-A-2002-116539, paragraph numbers [0022] to [0027] can be mentioned. Examples of other organic boron compounds include JP-A-6-348011, JP-A-7-128785, JP-A-7-140589, JP-A-7-306527, and JP-A-7-292014. Specific examples include organoboron transition metal coordination complexes and the like, and specific examples include ion complexes with cationic dyes.
Examples of phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide.
Examples of active esters include IRGACURE OXE01 (1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime)] manufactured by Ciba Specialty Chemicals), sulfonate esters, cyclic Active ester compounds and the like are included.
Specifically, Examples 1 to 21 described in JP-A 2000-80068 are particularly preferable.
Examples of the onium salts include aromatic diazonium salts, aromatic iodonium salts, and aromatic sulfonium salts.
Specific examples of the active halogens include Wakabayashi et al., “Bull Chem. Soc Japan” 42, 2924 (1969), US Pat. No. 3,905,815, JP-A-5-27830, M.M. P. Examples include compounds described in Hutt “Journal of Heterocyclic Chemistry”, Vol. 1 (No. 3), (1970), and in particular, oxazole compounds substituted with a trihalomethyl group: s-triazine compounds. More preferred are s-triazine derivatives in which at least one mono-, di- or trihalogen-substituted methyl group is bonded to the s-triazine ring. Specific examples include S-triazine and oxathiazole compounds, such as 2- (p-methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (p-methoxyphenyl). -4,6-bis (trichloromethyl) -s-triazine, 2- (p-styrylphenyl) -4,6-bis (trichloromethyl) -s-triazine, 2- (3-Br-4-di (ethyl) Acetate) amino) phenyl) -4,6-bis (trichloromethyl) -s-triazine, 2-trihalomethyl-5- (p-methoxyphenyl) -1,3,4-oxadiazole. Specifically, p.14 to p30 in JP-A-58-15503, p6-p10 in JP-A-55-77742, and p287 in JP-B-60-27673. 1-No. 8, p443-p444 No. of JP-A-60-239736. 1-No. 17, No. 4,701,399. Compounds such as 1-19 are particularly preferred.
Examples of inorganic complexes include bis (η5-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) titanium.
Examples of coumarins include 3-ketocoumarin.

These initiators may be used alone or in combination.
“Latest UV Curing Technology”, Technical Information Association, 1991, p. 159, and “UV curing system” written by Kayo Kiyomi, 1989, General Technology Center, p. Various examples are also described in 65-148 and are useful in the present invention.
Commercially available photo radical polymerization initiators include KAYACURE (DETX-S, BP-100, BDKM, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, ITX, QTX, BTC, manufactured by Nippon Kayaku Co., Ltd. MCA, etc.), Irgacure (651, 184, 500, 819, 907, 369, 1173, 1870, 2959, 4265, 4263, etc.) manufactured by Ciba Specialty Chemicals, Ltd., Esacure (KIP100F, KB1, manufactured by Sartomer) EB3, BP, X33, KT046, KT37, KIP150, TZT) and the like and combinations thereof are preferred examples.
It is preferable to use a photoinitiator in the range of 0.1-15 mass parts with respect to 100 mass parts of polyfunctional monomers, More preferably, it is the range of 1-10 mass parts.

<Photosensitizer>
In addition to the photopolymerization initiator, a photosensitizer may be used. Specific examples of the photosensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone and thioxanthone.
Further, one or more auxiliary agents such as an azide compound, a thiourea compound, and a mercapto compound may be used in combination.
Examples of commercially available photosensitizers include KAYACURE (DMBI, EPA) manufactured by Nippon Kayaku Co., Ltd.

<Thermal initiator>
As the thermal radical initiator, organic or inorganic peroxides, organic azo, diazo compounds, and the like can be used.
Specifically, benzoyl peroxide, halogen benzoyl peroxide, lauroyl peroxide, acetyl peroxide, dibutyl peroxide, cumene hydroperoxide, butyl hydroperoxide as organic peroxides, hydrogen peroxide, peroxides as inorganic peroxides. Diazo compounds such as 2,2′-azobis (isobutyronitrile), 2,2′-azobis (propionitrile), 1,1′-azobis (cyclohexanecarbonitrile) as azo compounds such as ammonium sulfate and potassium persulfate And diazoaminobenzene, p-nitrobenzenediazonium and the like.

[Translucent particles]
The translucent particles may be organic particles or inorganic particles. As the translucent particles, plastic beads are preferable, and those having particularly high transparency and a refractive index difference from the binder of 0.01 to 0.3 are preferable.
As organic particles, polymethyl methacrylate particles (refractive index 1.49), crosslinked poly (acryl-styrene) copolymer particles (refractive index 1.54), melamine resin particles (refractive index 1.57), polycarbonate particles ( Refractive index 1.57), polystyrene particles (refractive index 1.60), crosslinked polystyrene particles (refractive index 1.61), polyvinyl chloride particles (refractive index 1.60), benzoguanamine-melamine formaldehyde particles (refractive index 1. 68) etc. are used.
Examples of the inorganic particles include silica particles (refractive index: 1.44), alumina particles (refractive index: 1.63), zirconia particles, titania particles, and inorganic particles having hollows and pores.
Of these, cross-linked polystyrene particles, cross-linked poly ((meth) acrylate) particles, and cross-linked poly (acryl-styrene) particles are preferably used, and a binder is selected according to the refractive index of each light-transmitting particle selected from these particles. By adjusting the refractive index, the internal haze, surface haze, and centerline average roughness of the present invention can be achieved.

The refractive index of the binder (translucent resin) and translucent particles in the present invention is preferably 1.45 to 1.70, more preferably 1.48 to 1.65. In order to make the refractive index within the above range, the type and amount ratio of the binder and translucent particles may be appropriately selected. How to select can be easily known experimentally in advance.
Here, the refractive index of the binder can be quantitatively evaluated by directly measuring it with an Abbe refractometer or by measuring a spectral reflection spectrum or a spectral ellipsometry. The refractive index of the translucent particles is measured by measuring the turbidity by dispersing an equal amount of the translucent particles in the solvent in which the refractive index is changed by changing the mixing ratio of two types of solvents having different refractive indexes. It is measured by measuring the refractive index of the solvent when the turbidity is minimized with an Abbe refractometer.
In the case of the above translucent particles, the translucent particles easily settle in the binder, and therefore an inorganic filler such as silica may be added to prevent sedimentation. In addition, although an inorganic filler is effective in preventing sedimentation of translucent particles as the addition amount increases, it adversely affects the transparency of the coating film. Therefore, preferably, an inorganic filler having a particle size of 0.5 μm or less is contained in an amount of less than 0.1% by mass so as not to impair the transparency of the coating film with respect to the binder.
The average particle diameter of the translucent particles is preferably 0.5 to 10 μm, more preferably 2.0 to 8.0 μm. An average particle size of 0.5 μm or more and 10 μm or less is preferable because it does not cause display character blur and does not cause problems such as curling and cost increase.
Moreover, you may use together and use 2 or more types of translucent particle | grains from which a particle diameter differs. It is possible to impart an antiglare property with light-transmitting particles having a larger particle diameter, and to reduce surface roughness with light-transmitting particles having a smaller particle diameter.
The said translucent particle | grain is mix | blended so that 3-30 mass% may be contained in the addition layer total solid. More preferably, it is 5-20 mass%. If it is less than 3% by mass, the effect of addition is insufficient, and if it exceeds 30% by mass, problems such as image blur, surface turbidity and glare occur.
Moreover, the density of the translucent particles is preferably 10 to 1000 mg / m ² , more preferably 100 to 700 mg / m ² .

<Translucent particle preparation, classification method>
Examples of the method for producing the translucent particles include a suspension polymerization method, an emulsion polymerization method, a soap-free emulsion polymerization method, a dispersion polymerization method, a seed polymerization method, and the like, and any method may be used. These production methods are described in, for example, “Experimental Methods for Polymer Synthesis” (Takayuki Otsu and Masaaki Kinoshita, Chemical Dojinsha), pages 130 and 146 to 147, “Synthetic Polymers”, Vol. 246-290, 3rd volume, p. 1 to 108, etc., and Japanese Patent Nos. 2543503, 3508304, 2746275, 3521560, 3580320, and Japanese Patent Laid-Open No. 10-1561. Reference can be made to methods described in JP-A No. 7-2908, JP-A No. 5-297506, JP-A No. 2002-145919, and the like.
The particle size distribution of the translucent particles is preferably monodisperse particles in terms of haze value and diffusibility control, and uniformity of the coated surface. For example, when particles having a particle size of 20% or more than the average particle size are defined as coarse particles, the proportion of coarse particles is preferably 1% or less, more preferably 0.1% or less of the total number of particles. Yes, more preferably 0.01% or less. Particles having such a particle size distribution are also effective means of classification after preparation or synthesis reaction, and particles having a desired distribution can be obtained by increasing the number of classifications or increasing the degree of classification. .
It is preferable to use a method such as an air classification method, a centrifugal classification method, a sedimentation classification method, a filtration classification method, or an electrostatic classification method for classification.

  Two or more kinds of mat particles having different particle diameters may be used in combination. It is possible to impart anti-glare properties with mat particles having a larger particle size and to impart other optical characteristics with mat particles having a smaller particle size. For example, when an anti-glare antireflection film is attached to a high-definition display of 133 ppi or higher, a problem in display image quality called “glare” may occur. “Glitter” is derived from the fact that the pixels are enlarged or reduced due to the unevenness present on the surface of the antiglare and antireflection film, resulting in loss of brightness uniformity, but the particle size is smaller than the matte particles that impart antiglare properties. Thus, the use of mat particles different from the refractive index of the binder can greatly improve the performance.

As an example of a technique for producing an antiglare layer, a technique for producing an antiglare layer by spinodal decomposition of a plurality of polymers can be given as an example of a technique other than the use of translucent particles to exhibit antiglare properties.
The antiglare layer prepared by spinodal decomposition is composed of a plurality of polymers having different refractive indexes, and usually has a phase having at least a co-continuous phase structure in an operating atmosphere (particularly at room temperature of about 10 to 30 ° C.). A separation structure is formed. The co-continuous phase structure is formed by spinodal decomposition from a liquid phase containing a plurality of polymers (liquid phase at room temperature, for example, a mixed liquid or a solution). The bicontinuous phase structure is usually formed by spinodal decomposition through evaporation of a solvent using a composition (for example, a mixed solution or a solution) containing a plurality of polymers and forming a liquid phase at room temperature. Since such an antiglare layer is formed from a liquid phase, it has a uniform and fine co-continuous phase structure. When such a transmission type antiglare layer is used, incident light is scattered substantially isotropically, and directivity can be imparted to the transmitted scattered light. Therefore, both high light scattering and directivity can be achieved.
In order to enhance light scattering properties, a plurality of polymers can be used in combination so that the difference in refractive index is, for example, about 0.01 to 0.2, and preferably about 0.1 to 0.15. If the refractive index difference is 0.01 or more, the intensity of the transmitted scattered light does not decrease, and if the refractive index difference is 0.2 or less, high directivity can be imparted to the transmitted scattered light.
The plurality of polymers include, for example, styrene resins, (meth) acrylic resins, vinyl ester resins, vinyl ether resins, halogen-containing resins, olefin resins (including alicyclic olefin resins), polycarbonate resins, and polyesters. Resin, polyamide resin, thermoplastic polyurethane resin, polysulfone resin (polyethersulfone, polysulfone, etc.), polyphenylene ether resin (2,6-xylenol polymer, etc.), cellulose derivatives (cellulose esters, cellulose carbamates) , Cellulose ethers, etc.), silicone resins (polydimethylsiloxane, polymethylphenylsiloxane, etc.), rubbers or elastomers (diene rubbers such as polybutadiene, polyisoprene, styrene-butadiene copolymers, Acrylonitrile - butadiene copolymer, acrylic rubber, urethane rubber, silicone rubber, etc.) can be chosen a suitable combination and the like.
Preferred polymers include, for example, styrene resins, (meth) acrylic resins, vinyl ester resins, vinyl ether resins, halogen-containing resins, alicyclic olefin resins, polycarbonate resins, polyester resins, polyamide resins, Cellulose derivatives, silicone resins, rubbers or elastomers are included. As the plurality of polymers, a resin that is non-crystalline and is soluble in an organic solvent (in particular, a common solvent capable of dissolving the plurality of polymers) is usually used. In particular, resins with high moldability or film formability, transparency and weather resistance, such as styrene resins, (meth) acrylic resins, alicyclic olefin resins, polyester resins, cellulose derivatives (cellulose esters, etc.) Etc. are preferable.
These plural polymers can be used in appropriate combinations. For example, in a combination of polymers, at least one polymer is selected from cellulose derivatives, particularly cellulose esters (eg, cellulose C _2-4 alkyls such as cellulose diacetate, cellulose triacetate, cellulose acetate propionate, cellulose acetate butyrate, etc. Carboxylic acid esters) and may be combined with other polymers.
The glass transition temperature of the polymer can be selected from the range of, for example, −100 ° C. to 250 ° C., preferably −50 to 230 ° C., more preferably about 0 to 200 ° C. (for example, about 50 to 180 ° C.). From the viewpoint of sheet strength and rigidity, the glass transition temperature of at least one of the constituent polymers is 50 ° C. or higher (for example, about 70 to 200 ° C.), preferably 100 ° C. or higher (for example, 100 to 170 ° C.). It is advantageous that The weight average molecular weight of the polymer can be selected from the range of, for example, 1,000,000 or less (about 10,000 to 1,000,000), preferably about 10,000 to 700,000.

Since the present invention employs a wet method in which a solvent is evaporated from a liquid phase containing a plurality of polymers and spinodal decomposition is performed, in principle, a substantially isotropic common is used regardless of the compatibility of the plurality of polymers. An antiglare layer having a continuous phase structure can be formed. For this reason, it may be configured by combining a plurality of mutually compatible polymers. However, in order to easily control the phase separation structure by spinodal decomposition and to form a co-continuous phase structure efficiently, incompatible (phase separation) In many cases, a plurality of polymers are combined.
The plurality of polymers can be constituted by a combination of the first polymer and the second polymer, and each of the first polymer and the second polymer may be constituted by a single resin or a plurality of resins. Also good. The combination of the first polymer and the second polymer is not particularly limited. For example, when the first polymer is a cellulose derivative (for example, cellulose esters such as cellulose acetate propionate), the second polymer is a styrene resin (polystyrene, styrene-acrylonitrile copolymer, etc.), (meta ) Acrylic resins (such as polymethyl methacrylate), alicyclic olefin resins (such as polymers containing norbornene), polycarbonate resins, polyester resins (the poly C _2-4 alkylene arylate copolyester) Etc.).
The ratio of the first polymer to the second polymer is, for example, the former / the latter = about 10/90 to 90/10 (mass ratio), preferably about 20/80 to 80/20 (mass ratio), and more preferably Is about 30/70 to 70/30 (mass ratio), particularly about 40/60 to 60/40 (mass ratio). When the ratio of one polymer is too large, the volume ratio between the separated phases is biased, so that the intensity of scattered light decreases. In addition, when forming a sheet | seat with a 3 or more some polymer, content of each polymer is 1-90 mass% normally (for example, 1-70 mass%, Preferably 5-70 mass%, More preferably, it is 10 Can be selected from a range of about 70 mass%.
The antiglare layer has at least a co-continuous phase structure. The co-continuous phase structure is sometimes referred to as a co-continuous structure or a three-dimensional continuous or connected structure, and means a structure in which at least two constituent polymer phases are continuous (for example, a network structure). . The antiglare layer only needs to have at least a co-continuous phase structure, and may have a structure in which a co-continuous phase structure and a droplet phase structure (independent or isolated phase structure) are mixed. In spinodal decomposition, a co-continuous phase structure is formed as the phase separation progresses, and when the phase separation is further advanced, the continuous phase becomes discontinuous due to its surface tension, and the droplet phase structure (spherical, true spherical) Sea island structure of independent phase). Therefore, depending on the degree of phase separation, an intermediate structure between the co-continuous phase structure and the droplet phase structure, that is, a phase structure in the process of shifting from the co-continuous phase to the droplet phase can be formed. In the present invention, the intermediate structure is also referred to as a co-continuous phase structure. When the phase separation structure is a mixed structure of a co-continuous phase structure and a droplet structure, the ratio of the droplet phase (independent polymer phase) is, for example, 30% or less (volume ratio), preferably 10% or less ( Volume ratio). The shape of the co-continuous phase structure is not particularly limited, and may be a network shape, particularly a random network shape.
The bicontinuous phase structure is generally isotropic with reduced anisotropy in the layer or sheet plane. Note that isotropic means that the average interphase distance of the co-continuous phase structure is substantially equal in any direction in the sheet plane.
The bicontinuous phase structure usually has regularity in the interphase distance (distance between the same phases). For this reason, the light scattered on the sheet is directed to a specific direction by Bragg reflection. Therefore, even when mounted on a reflective liquid crystal display device, the transmitted scattered light can be directed in a certain direction, the display screen can be made highly bright, and a conventional particle-dispersed transmissive antiglare layer The problem that cannot be solved, that is, the reflection of a light source (for example, a fluorescent lamp) on the panel can be avoided.
In the antiglare layer, the average interphase distance of the co-continuous phase is, for example, about 0.5 to 20 μm (for example, 1 to 20 μm), preferably about 1 to 15 μm (for example, 1 to 10 μm). If the average interphase distance is too small, it is difficult to obtain high scattered light intensity, and if the average interphase distance is too large, the directivity of transmitted scattered light decreases.
In addition, the average interphase distance of the co-continuous layer can be calculated from a micrograph (such as a transmission microscope, a phase contrast microscope, or a confocal laser microscope) of the antiglare layer. In addition, the scattering angle θ at which the scattered light intensity is maximized is measured by a method similar to the scattered light directivity evaluation method described later, and the average interphase distance d of the co-continuous phase is calculated from the following Bragg reflection condition equation. May be.

2d · sin (θ / 2) = λ
(Where d is the average interphase distance of co-continuous phases, θ is the scattering angle, and λ is the wavelength of light)

As an example of a method for producing an antiglare layer, a method for producing an antiglare layer by an embossing method may be given as an example of a method other than the use of translucent particles to exhibit antiglare properties.
The antiglare layer produced by the embossing method is an ionizing radiation curable resin composition or a thermosetting resin composition formed on a transparent substrate with a mat-like shaped film having fine irregularities on the surface. A light diffusion layer consisting essentially of is formed.
When the resin is an ionizing radiation curable resin composition, the antiglare layer is produced by coating the ionizing radiation curable resin composition on a transparent substrate and then applying the ionizing radiation curable resin. By laminating a mat-shaped shaped film having fine irregularities on the surface of the uncured coating film of the composition, and then irradiating ionizing radiation on the coated film on which the shaped film is laminated, It is preferable to manufacture the coating film of the ionizing radiation curable resin composition by a manufacturing method in which the shaped film is peeled from the cured coating film of the ionizing radiation curable resin.
When the resin is a thermosetting resin composition, the thermosetting resin composition is applied on a transparent substrate, and then the uncured coating film of the applied thermosetting resin composition is applied. A mat-like shaped film having fine irregularities on the surface is laminated, and then the coating film laminated with the shaped film is heated and cured, and then the cured thermosetting resin composition is applied. It is preferable to manufacture by the manufacturing method which peels a shaping film from a film | membrane.
When laminating the shaping film on the coating film of the uncured ionizing radiation curable resin composition, if the coated resin is of a solvent dilution type, the solvent is dried and then laminating, If the applied resin is solventless, lamination is performed as it is.
The film forming component of the ionizing radiation curable resin composition used for the light diffusing layer of the embossing method is preferably one having an acrylate functional group, such as a polyester resin, polyether resin, acrylic resin having a relatively low molecular weight. , Epoxy or urethane resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, oligomers or prepolymers of polyfunctional compounds such as polyhydric alcohols and prepolymers, and ethyl (meth) as a reactive diluent Monofunctional monomers such as acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone and polyfunctional monomers such as trimethylolpropane tri (meth) acrylate, hexanediol (meth) acrylate, tri Lopylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) ) Those containing a relatively large amount of acrylate or the like can be used.
Particularly preferably, a mixture of polyester acrylate and polyurethane acrylate is used. The reason is that polyester acrylate is very hard and suitable for obtaining a hard coat, but polyester acrylate alone has low impact and is brittle. In order to give the properties, polyurethane acrylate is used in combination. The blending ratio of polyurethane acrylate to 100 parts by mass of polyester acrylate is 30 parts by mass or less. If this value is exceeded, the coating film is too soft and the hardness is lost.
Further, in order to make the ionizing radiation curable resin composition into an ultraviolet curable resin composition, acetophenones, benzophenones, Michler benzoyl benzoate, α-amyloxime ester, tetra Methyl thiuram monosulfide, thioxanthones, and n-butylamine, triethylamine, tri-n-butylphosphine and the like can be used as a photosensitizer. Particularly in the present invention, it is preferable to mix urethane acrylate as an oligomer and dipentaerythritol hexa (meth) acrylate as a monomer.
The paint for forming a light-diffusing and hard coat (scratch-resistant) coating film contains 10 parts by mass or more and 100 parts by mass or less of solvent-drying resin with respect to 100 parts by mass of ionizing radiation curable resin Also good. As the solvent-drying resin, a thermoplastic resin is mainly used. The types of solvent-drying thermoplastic resins added to the ionizing radiation curable resin are usually used, but especially when a mixture of polyester acrylate and polyurethane acrylate is used for the ionizing radiation curable resin. In the solvent drying type resin, polymethyl methacrylate acrylate or polybutyl methacrylate acrylate can keep the hardness of the coating film high. In addition, in this case, since the refractive index is close to that of the main ionizing radiation curable resin, the transparency of the coating film is not impaired, and it is advantageous in terms of transparency, particularly low haze value, high transmittance and compatibility.
Further, when a cellulose resin such as triacetyl cellulose is used as the transparent substrate, the solvent-drying resin to be included in the ionizing radiation curable resin includes nitrocellulose, acetyl cellulose, cellulose acetate propionate, ethyl hydroxyethyl cellulose, etc. The cellulosic resin is advantageous in terms of adhesion and transparency of the coating film.

The film thickness of the antiglare layer is preferably 1 to 25 μm, and more preferably 2 to 15 μm. If it is too thin, the hard property is insufficient, and if it is too thick, curling and brittleness may be deteriorated and workability may be lowered.

  The center line average roughness (Ra) of the antiglare layer is preferably in the range of 0.01 to 0.40 μm, and more preferably in the range of 0.05 to 0.20 μm. If it exceeds 0.40 μm, problems such as glare and whitening of the surface when external light is reflected occur. Further, it is preferable that the value of the transmitted image definition is 5 to 60%.

  The strength of the antiglare layer is preferably 3H or more, more preferably 4H or more, and most preferably 5H or more in the pencil hardness test.

<Ultraviolet absorber>
An ultraviolet absorber can be added to the hard coat layer. Since the polarizer is easily deteriorated by ultraviolet rays, it is preferable that the polarizing plate protective film has an ultraviolet absorption capability.
From the viewpoint of excellent UV absorption and good liquid crystal display properties, the UV absorber has a transmittance of 0 to 50 nm at a wavelength of 380 nm in the entire polarizing plate protective film after the UV absorber is added to each layer. %, Preferably 0 to 30%, more preferably 0 to 10%, and the transmittance at 600 nm is 80 to 100%, preferably 85 to 100%, more preferably 90 to 100%.

A well-known thing can be used as a ultraviolet absorber. Examples thereof include benzotriazole-based, benzophenone-based, salicylic acid phenyl ester-based, and triazine-based ultraviolet absorbers.
Examples of the benzotriazole ultraviolet absorber include 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- (2H-benzotriazol-2-yl) -p-cresol, and 2- (2H-benzotriazole-2). -Yl) -4,6-di-tert-pentylphenol, 2- (2′-hydroxy-5 ′ methacryloxyethylphenyl) -2H-benzotriazole and the like.
Examples of benzophenone-based ultraviolet absorbers include 2-hydroxy-4-octoxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxy-4′-chlorobenzophenone, 2,2-dihydroxy-4-methoxybenzophenone, 2,2-dihydroxy-4,4′-dimethoxybenzophenone and the like can be mentioned.
Examples of salicylic acid phenyl ester ultraviolet absorbers include pt-butylphenyl salicylic acid ester.
Examples of triazine ultraviolet absorbers include 2,4-diphenyl-6- (2-hydroxy-4-methoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-). Ethoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-4-propoxyphenyl) -1,3,5-triazine, 2,4-diphenyl- (2-hydroxy-4-) Butoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-butoxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2- Hydroxy-4-hexyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-octyloxyphenyl) -1,3,5-triazi 2,4-diphenyl-6- (2-hydroxy-4-dodecyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-benzyloxyphenyl) -1 , 3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-butoxyethoxyphenyl) -1,3,5-triazine, and the like.

Among these UV absorbers, the use of a compound having a functional group polymerizable with the polymerizable monomer of the hard coat layer is effective in increasing the hardness of the hard coat layer, suppressing bleed out, and improving durability. preferable.
Examples of the compound having such a polysynthetic functional group include 2-hydroxybenzophenone derivatives and 2-hydroxyphenylbenzotriazole derivatives.
Specific examples of 2-hydroxybenzophenone derivatives include 2-hydroxy-4-acryloyloxybenzophenone, 2-hydroxy-4-methacryloyloxybenzophenone, 2-hydroxy-4- (2-acryloyloxy) ethoxybenzophenone, 2-hydroxy- Examples include 4- (2-methacryloyloxy) ethoxybenzophenone and 2-hydroxy-4- (2-methyl-2-acryloyloxy) ethoxybenzophenone.
Specific examples of 2-hydroxyphenylbenzotriazole derivatives include 2- [2'-hydroxy-5 '-(methacryloyloxy) ethylphenyl] -2H-benzotriazole, 2- [2'-hydroxy-5'-(methacryloyl). Oxy) phenyl] benzotriazole, 2- [2'-hydroxy-5 '-(acryloyloxy) phenyl] benzotriazole, 2- [2'-hydroxy-3'-t-butyl-5'-(methacryloyloxy) phenyl Benzotriazole, 2- [2'-hydroxy-3'-methyl-5 '-(acryloyloxy) phenyl] benzotriazole, 2- [2'-hydroxy-5'-(methacryloyloxypropyl) phenyl] -5 Chlorobenzotritriazole, 2- [2'-hydroxy-5 '-(me Acryloyloxyethyl) phenyl] benzotriazole, 2- [2'-hydroxy-5 '-(acryloyloxyethyl) phenyl] benzotriazole, 2- [2'-hydroxy-3'-t-butyl-5'-( Methacryloyloxyethyl) phenyl] benzotriazole, 2- [2'-hydroxy-3'-methyl-5 '-(acryloyloxyethyl) phenyl] benzotriazole, 2- [2'-hydroxy-5'-(methacryloyloxypropyl) ) Phenyl] -5-chlorobenzotriazole, 2- [2'-hydroxy-5 '-(acryloyloxybutyl) phenyl] -5-methylbenzotriazole, [2-hydroxy-3-tert-butyl-5- ( Acryloyloxyethoxycarbonylethyl) phenyl] benzotriazol And the like.
Two or more kinds of ultraviolet absorbers having these polymerizable functional groups can be used. Further, when used in combination with an ultraviolet absorber having no polymerizable functional group, bleeding out of the ultraviolet absorber can be suppressed, and the content of the ultraviolet absorber in the hard coat layer can be increased.

  The light transmittance in the wavelength region of 200 to 340 nm follows the generally known Beer-Lambert law. Therefore, the amount of added UV absorber and the thickness of the hard coat layer required to achieve the light transmittance target are as follows. Can be determined by calculation.

  When the hard coat layer is an ultraviolet curable resin, it is preferable that the transmittance at a wavelength longer than 340 nm is as high as possible in order to improve the ultraviolet absorption of the ultraviolet sensitive radical polymerizable initiator. This object can be achieved by selecting an ultraviolet absorber having an absorption peak at a wavelength lower than 340 nm. For example, in a benzotriazole type ultraviolet absorber, 2- (2′-hydroxy-5 ′ methacryloxyethylphenyl) -2H-benzotriazole, 2- (2H-benzotriazol-2-yl) -p-cresol; In the ultraviolet absorber, 2,4-diphenyl-6- (2-hydroxy-4-dodecyloxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-benzyl) Oxyphenyl) -1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-butoxyethoxyphenyl) -1,3,5-triazine is preferably used.

[Undercoat layer]
In the present invention, an undercoat layer further containing a hydrophilic polymer can be provided on the easy-adhesion layer. The undercoat layer is preferably provided on an easy-adhesion layer provided on the opposite side of the transparent support from which the hard coat layer is provided. The adhesion with the polarizer can be further improved.

<Hydrophilic polymer>
Examples of hydrophilic polymers include acylated gelatin such as gelatin, phthalated gelatin, maleated gelatin, cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, grafted gelatin obtained by grafting acrylic acid, methacrylic acid, amide or the like onto gelatin, Polyvinyl alcohol, polyhydroxyalkyl acrylate, polyvinyl pyrrolidone, copoly-vinyl pyrrolidone-vinyl acetate, casein, agarose, albumin, sodium alginate, polysaccharide, agar, starch, grafted starch, polyacrylamide, N-substituted acrylamide, N-substituted methacrylic Synthetic or natural hydrophilic polymer compounds such as homo- or copolymers such as amides, or partial hydrolysates thereof are used. These are used alone or in combination. A preferred hydrophilic polymer is gelatin or a derivative thereof.

  The undercoat layer can be formed by applying a coating composition containing the hydrophilic polymer onto the easy-adhesion layer. The coating composition is composed of the hydrophilic polymer and a solvent. Examples of the solvent include water and alcohols. The coating method is a generally known coating method such as dip coating, air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, or US Pat. No. 2,681,294. It can apply | coat by the extrusion method etc. which use a hopper.

  The thickness of the undercoat layer is preferably in the range of 0.05 to 1.0 μm. If it is thinner than 0.05 μm, it is difficult to obtain sufficient adhesiveness, and if it is thicker than 1.0 μm, the adhesive effect is saturated.

An ultraviolet absorber may be added to the undercoat layer as necessary.
From the viewpoint of excellent UV absorption and good liquid crystal display properties, the UV absorber has a transmittance of 0 to 50 nm at a wavelength of 380 nm in the entire polarizing plate protective film after the UV absorber is added to each layer. %, Preferably 0 to 30%, more preferably 0 to 10%, and the transmittance at 600 nm is 80 to 100%, preferably 85 to 100%, more preferably 90 to 100%. Specifically, the same thing as the ultraviolet absorber used for the above-mentioned hard-coat layer can be mentioned.
Further, the amount used is preferably 0.1 to 10% by mass, more preferably 0.5 to 5% by mass in the solid content of the undercoat layer.

[Other layers]
In the present invention, other layers such as a high refractive index layer, a medium refractive index layer, a low refractive index layer, and an antistatic layer can be provided. Hereinafter, these layers will be described.

[High refractive index layer, medium refractive index layer]
The film of the present invention can be provided with a high refractive index layer and a medium refractive index layer to enhance antireflection properties.
In the following specification, the high refractive index layer and the medium refractive index layer may be collectively referred to as a high refractive index layer. In the present invention, “high”, “medium”, and “low” in the high refractive index layer, medium refractive index layer, and low refractive index layer represent the relative refractive index relationship between the layers. In terms of the relationship with the transparent support, the refractive index preferably satisfies the relationship of transparent support> low refractive index layer, high refractive index layer> transparent support.
In the present specification, the high refractive index layer, the middle refractive index layer, and the low refractive index layer may be collectively referred to as an antireflection layer.

  In order to construct a low refractive index layer on a high refractive index layer to form an antireflection layer, the refractive index of the high refractive index layer is preferably 1.55 to 2.40, more preferably It is 1.60 to 2.20, more preferably 1.65 to 2.10, and most preferably 1.80 to 2.00.

  When an antireflective layer is formed by coating a medium refractive index layer, a high refractive index layer, and a low refractive index layer in order from the support, the refractive index of the high refractive index layer is 1.65 to 2.40. Preferably, it is 1.70-2.20. The refractive index of the middle refractive index layer is adjusted to be a value between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. The refractive index of the middle refractive index layer is preferably 1.55-1.80.

The inorganic particles mainly composed of TiO ₂ used for the high refractive index layer and the medium refractive index layer are used for forming the high refractive index layer and the medium refractive index layer in the state of dispersion.
In the dispersion of the inorganic particles, the inorganic particles are dispersed in the dispersion medium in the presence of a dispersant.

  The high refractive index layer and the medium refractive index layer used in the present invention are preferably used in a dispersion liquid in which inorganic particles are dispersed in a dispersion medium, preferably a binder precursor (for example, an ionizing radiation curable multifunctional material) necessary for matrix formation. Monomers, polyfunctional oligomers, etc.), a photopolymerization initiator, etc., to form a coating composition for forming a high refractive index layer and a medium refractive index layer, and for forming a high refractive index layer and a medium refractive index layer on a transparent support. The coating composition is preferably applied and cured by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound (for example, a polyfunctional monomer or a polyfunctional oligomer).

Furthermore, it is preferable to cause the binder of the high refractive index layer and the medium refractive index layer to undergo a crosslinking reaction or a polymerization reaction with the dispersant simultaneously with or after the coating of the layer.
The binder of the high refractive index layer and the medium refractive index layer produced in this way is, for example, the above-mentioned preferred dispersant and ionizing radiation curable polyfunctional monomer or polyfunctional oligomer are crosslinked or polymerized to form a binder. The anionic group of the dispersant is incorporated. Furthermore, the binder of the high refractive index layer and the medium refractive index layer has a function in which the anionic group maintains the dispersion state of the inorganic particles, and the crosslinked or polymerized structure imparts a film forming ability to the binder and contains inorganic particles. To improve the physical strength, chemical resistance and weather resistance of the high refractive index layer and medium refractive index layer.

  The binder of the high refractive index layer is added in an amount of 5 to 80% by mass based on the solid content of the coating composition of the layer.

The content of the inorganic particles in the high refractive index layer is preferably 10 to 90% by mass, more preferably 15 to 80% by mass, and particularly preferably 15 to 75% by mass with respect to the mass of the high refractive index layer. . Two or more kinds of inorganic particles may be used in combination in the high refractive index layer.
When the low refractive index layer is provided on the high refractive index layer, the refractive index of the high refractive index layer is preferably higher than the refractive index of the transparent support.
The high refractive index layer contains an ionizing radiation curable compound containing an aromatic ring, an ionizing radiation curable compound containing a halogenated element other than fluorine (for example, Br, I, Cl, etc.), and atoms such as S, N, P, etc. A binder obtained by a crosslinking or polymerization reaction such as an ionizing radiation curable compound can also be preferably used.

  The film thickness of the high refractive index layer can be appropriately designed depending on the application. When using a high refractive index layer as an optical interference layer, 30-200 nm is preferable, More preferably, it is 50-170 nm, Most preferably, it is 60-150 nm.

The haze of the high refractive index layer is preferably as low as possible when it does not contain particles that impart an antiglare function. It is preferably 5% or less, more preferably 3% or less, and particularly preferably 1% or less.
The high refractive index layer is preferably constructed directly on the hard coat layer or via another layer.

(Low refractive index layer)
When reducing the reflectance of the film of the present invention, it is preferable to provide a low refractive index layer.
The refractive index of the low refractive index layer is preferably 1.20 to 1.46, more preferably 1.25 to 1.46, and particularly preferably 1.30 to 1.46.
The thickness of the low refractive index layer is preferably 50 to 200 nm, and more preferably 70 to 100 nm. The haze of the low refractive index layer is preferably 3% or less, more preferably 2% or less, and most preferably 1% or less. The specific strength of the low refractive index layer is preferably H or higher, more preferably 2H or higher, and most preferably 3H or higher in a pencil hardness test under a 500 g load.
Further, in order to improve the antifouling performance of the optical film, it is preferable that the contact angle of water on the surface is 90 degrees or more. More preferably, it is 95 degrees or more, and particularly preferably 100 degrees or more.

  The curable composition for forming the low refractive index layer preferably contains (A) a fluorine-containing polymer, (B) inorganic particles, and (C) an organosilane compound.

  In the low refractive index layer, a binder is used to disperse and fix the particles. As the binder, the binder described in the hard coat layer can be used, but it is preferable to use a fluorine-containing polymer having a low refractive index or a fluorine-containing sol-gel material. The fluorine-containing polymer or fluorine-containing sol-gel is a material that has a dynamic friction coefficient of 0.03 to 0.30 on the surface of the low refractive index layer formed by crosslinking by heat or ionizing radiation and a contact angle of 85 to 120 ° with water. Is preferred.

[Anti-fouling layer]
An antifouling layer can be provided on the outermost surface of the present invention. The antifouling layer lowers the surface energy of the antireflection layer and makes it difficult to attach hydrophilic or lipophilic stains.
The antifouling layer can be formed using a fluorine-containing polymer or an antifouling agent.
The thickness of the antifouling layer is preferably 2 to 100 nm, and more preferably 5 to 30 nm.

(Antistatic layer)
It is also effective to provide an antistatic layer, in which case it is formed as follows.
In the antistatic layer of the present invention, the haze of the low chargeable support obtained by providing the antistatic layer is 3% or less, and the surface electrical resistance of the surface layer of the resulting polarizing plate protective film is 1 × 10 ^6. Conductivity is imparted so as to be in the range of ˜1 × 10 ¹¹ Ω. By providing the antistatic layer, it is possible to suppress the occurrence of trouble with dust caused by static electricity that occurs in the manufacturing process of handling the plastic support.

The antistatic layer is a layer containing conductive metal oxide particles, and generally further contains a binder. The conductive metal oxide particles are preferably acicular particles having a major axis to minor axis ratio (major axis / minor axis) in the range of 3 to 50. In particular, those having a major axis / minor axis in the range of 10 to 50 are preferable. The minor axis of such acicular particles is preferably in the range of 0.001 to 0.1 μm, and particularly preferably in the range of 0.01 to 0.02 μm. The major axis is preferably in the range of 0.1 to 5.0 μm, and particularly preferably in the range of 0.1 to 2.0 μm.
Examples of the conductive metal oxide particles include ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , MgO, BaO and MoO _3, and composite oxides thereof, and further to these metal oxides. Mention may be made of metal oxides containing different atoms. As the metal oxide, SnO ₂ , ZnO, Al ₂ O ₃ , TiO ₂ , In ₂ O ₃ and MgO are preferable, SnO ₂ , ZnO, In ₂ O ₂ and TiO ₂ are preferable, and SnO ₂ is particularly preferable. . Examples of containing a small amount of different atoms include Zn or Al, In, TiO ₂ Nb or Ta, In ₂ O ₃ Sn, and SnO ₂ Sb, Nb or halogen elements. An element doped with 0.01 to 30 mol% (preferably 0.1 to 10 mol%) of the element can be used. If the amount of the different element added is 0.01 mol% or more, sufficient conductivity can be imparted to the oxide or composite oxide, and if it is 30 mol% or less, the degree of blackening of the particles increases. No blackening of the antistatic layer occurs. Therefore, in the present invention, the material of the conductive metal oxide particles is preferably one containing a small amount of a different element with respect to the metal oxide or the composite metal oxide. Also preferred are those containing an oxygen defect in the crystal structure. As the conductive metal oxide particles containing a small amount of the dissimilar atom, SnO ₂ particles are preferred antimony-doped, SnO ₂ particles are preferred which are particularly doped antimony 0.2-2.0 mol%. Therefore, in the present invention, it is advantageous to use a metal oxide particle such as antimony-doped SnO ₂ having the dimensions of the short axis and the long axis in order to form an antistatic layer that is transparent and has good conductivity. is there.
About the reason why an antistatic layer which is transparent and has good conductivity can be advantageously formed by using acicular metal oxide particles having the dimensions of the short axis and the long axis (eg, antimony-doped SnO ₂ ). Is considered as follows. In the antistatic layer, the needle-like metal oxide particles extend long in the major axis direction parallel to the surface of the antistatic layer, but the length of the minor axis in the thickness direction of the layer. It only occupies. Since such acicular metal oxide particles are long in the major axis direction as described above, they are easier to contact with each other than ordinary spherical particles, and high conductivity can be obtained even in a small amount. Accordingly, the surface electrical resistance can be reduced without impairing the transparency. Further, in the needle-like metal oxide particles, the minor axis diameter is usually smaller than or substantially the same as the thickness of the antistatic layer and rarely protrudes on the surface. Therefore, it is almost completely covered by the surface layer provided on the antistatic layer.

The antistatic layer of the present invention generally contains a binder that disperses and supports conductive metal oxide particles. As a material for the binder, various polymers such as an acrylic resin, a vinyl resin, a polyurethane resin, and a polyester resin can be used. From the viewpoint of preventing powder falling, a cured product of a polymer (preferably an acrylic resin, a vinyl resin, a polyurethane resin, or a polyester resin) and a carbodiimide compound is preferable. In the present invention, from the viewpoint of maintaining a good working environment and preventing air pollution, it is preferable to use either a water-soluble polymer or a carbodiimide compound, or an aqueous dispersion such as an emulsion. Further, the polymer has any group of a methylol group, a hydroxyl group, a carboxyl group, and an amino group so that a crosslinking reaction with the carbodiimide compound is possible. A hydroxyl group and a carboxyl group are preferred, and a carboxyl group is particularly preferred. The content of hydroxyl group or carboxyl group in the polymer is preferably 0.0001 to 1 equivalent / 1 kg, particularly preferably 0.001 to 1 equivalent / 1 kg.
Acrylic resins include acrylic acid esters such as acrylic acid and alkyl acrylate, acrylamide, acrylonitrile, methacrylic acid esters such as methacrylic acid and alkyl methacrylate, and homopolymers of any monomer of methacrylamide and methacrylonitrile. Or the copolymer obtained by superposition | polymerization of 2 or more types of these monomers can be mentioned. Among these, homopolymers of monomers of acrylic acid esters such as alkyl acrylates and methacrylic acid esters such as alkyl methacrylates, or copolymers obtained by polymerization of two or more of these monomers preferable. For example, mention may be made of homopolymers of monomers of acrylic acid esters and methacrylic acid esters having an alkyl group having 1 to 6 carbon atoms, or copolymers obtained by polymerization of two or more of these monomers. it can. The acrylic resin has the above composition as a main component and, for example, partially uses a monomer having any group of a methylol group, a hydroxyl group, a carboxyl group, and an amino group so that a crosslinking reaction with a carbodiimide compound is possible. The resulting polymer.
Examples of the vinyl resin include polyvinyl alcohol, acid-modified polyvinyl alcohol, polyvinyl formal, polyvinyl butyral, polyvinyl methyl ether, polyolefin, ethylene / butadiene copolymer, polyvinyl acetate, vinyl chloride / vinyl acetate copolymer, vinyl chloride / ( A meth) acrylic acid ester copolymer and an ethylene / vinyl acetate copolymer (preferably ethylene / vinyl acetate / (meth) acrylic acid ester copolymer) can be mentioned. Among these, polyvinyl alcohol, acid-modified polyvinyl alcohol, polyvinyl polymer, polyolefin, ethylene / butadiene copolymer and ethylene / vinyl acetate copolymer (preferably ethylene / vinyl acetate / acrylic acid ester copolymer). Is preferred. In the case of polyvinyl alcohol, acid-modified polyvinyl alcohol, polyvinyl formal, polyvinyl butyral, polyvinyl methyl ether, and polyvinyl acetate, for example, a vinyl alcohol unit is left in the polymer so that the vinyl resin can undergo a crosslinking reaction with a carbodiimide compound. Thus, the polymer having a hydroxyl group is used, and the other polymer is, for example, a crosslinkable polymer by partially using a monomer having any of a methylol group, a hydroxyl group, a carboxyl group, and an amino group.
Examples of the polyurethane resin include polyhydroxy compounds (eg, ethylene glycol, propylene glycol, glycerin, trimethylolpropane), aliphatic polyester polyols obtained by reaction of polyhydroxy compounds and polybasic acids, polyether polyols (eg, Polyurethane derived from poly (oxypropylene ether) polyol, poly (oxyethylene-propylene ether) polyol), polycarbonate-based polyol, and polyethylene terephthalate polyol, or a mixture thereof and polyisocyanate can be given. In the polyurethane resin, for example, the hydroxyl group remaining unreacted after the reaction between polyol and polyisocyanate can be used as a functional group capable of crosslinking reaction with a carbodiimide compound.
As the polyester resin, generally used is a polymer obtained by reacting a polyhydroxy compound (eg, ethylene glycol, propylene glycol, glycerin, trimethylolpropane) with a polybasic acid. In the above-mentioned polyester resin, for example, the hydroxyl group and carboxyl group remaining unreacted after the reaction between the polyol and the polybasic acid can be used as a functional group capable of crosslinking reaction with the carbodiimide compound. Of course, a third component having a functional group such as a hydroxyl group may be added.
Among the above polymers, acrylic resins and polyurethane resins are preferable, and acrylic resins are particularly preferable.
As the carbodiimide compound used in the present invention, it is preferable to use a compound part having a plurality of carbodiimide structures in the molecule.
Polycarbodiimide is usually synthesized by a condensation reaction of organic diisocyanate. Here, the organic group of the organic diisocyanate used for the synthesis of the compound having a plurality of carbodiimide structures in the molecule is not particularly limited, and either aromatic or aliphatic, or a mixed system thereof can be used. An aliphatic system is particularly preferred from the viewpoint of reactivity.
As the synthetic raw material, organic isocyanate, organic diisocyanate, organic triisocyanate and the like are used.
As examples of organic isocyanates, aromatic isocyanates, aliphatic isocyanates, and mixtures thereof can be used.
Specifically, 4,4′-diphenylmethane diisocyanate, 4,4-diphenyldimethylmethane diisocyanate, 1,4-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, cyclohexane Diisocyanate, xylylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, 1,3-phenylene diisocyanate, etc. are used. As organic monoisocyanates, isophorone isocyanate, phenyl isocyanate are used. Cyclohexyl isocyanate, butyl isocyanate, naphthyl isocyanate and the like are used.
Moreover, the carbodiimide type compound that can be used in the present invention is also available as a commercial product such as Carbodilite V-02-L2 (trade name: manufactured by Nisshinbo Co., Ltd.).
The carbodiimide compound of the present invention is preferably added in an amount of 1 to 200% by mass, more preferably 5 to 100% by mass, based on the binder.

In order to form the antistatic layer of the present invention, first, for example, a dispersion liquid in which the conductive metal oxide particles are dispersed as they are or in a solvent such as water (including a dispersant and a binder as required) is used. A coating solution for forming an antistatic layer is prepared by adding and mixing (dispersing as required) an aqueous dispersion or an aqueous solution containing the binder (eg, polymer, carbodiimide compound and appropriate additive). The antistatic layer is formed by applying a coating solution for forming the antistatic layer on the surface of a plastic film, such as a dip coating method, an air knife coating method, a curtain coating method, a wire bar coating method, or a gravure coating method. It can be applied by an extrusion coating method or the like.
The layer thickness of the antistatic layer of the present invention is preferably in the range of 0.01 to 1 μm, more preferably in the range of 0.01 to 0.2 μm. If the coating agent is less than 0.01 μm, it is difficult to uniformly apply the coating agent, and uneven coating tends to occur on the product. If it exceeds 1 μm, the antistatic performance and scratch resistance may be inferior. The conductive metal oxide particles are preferably contained in the antistatic layer in the range of 10 to 1000% by mass with respect to the binder (for example, the total of the polymer and the carbodiimide compound), and more preferably 100 to 500%. A range of mass% is preferred. If it is less than 10% by mass, sufficient antistatic properties cannot be obtained, and if it exceeds 1000% by mass, the haze becomes too high.

The antistatic layer of the present invention and the following surface layer can be used in combination with additives such as surfactants and slip agents, if necessary. Examples of the surfactant include known anionic surfactants, cationic surfactants, amphoteric surfactants and nonionic surfactants. Examples of slip agents include natural waxes such as carnauba wax, phosphate esters of higher alcohols having 8 to 22 carbon atoms or amino salts thereof; palmitic acid, stearic acid, behenic acid and esters thereof; and silicone compounds. Can do.
In the present invention, a surface layer is provided on the antistatic layer. The surface layer is provided mainly to assist the adhesion imparting with the adhesive layer and the anti-detachment function of the conductive metal oxide particles of the antistatic layer. As the material for the surface layer, various polymers such as acrylic resin, vinyl resin, polyurethane resin, and polyester resin can be generally used, and polymers described as the binder in the antistatic layer are preferable.
The crosslinking agent used for the surface layer is preferably an epoxy compound. Examples of the epoxy compound include 1,4-bis (2 ′, 3′-epoxypropyloxy) butane, 1,3,5-triglycidyl isocyanurate, 1,3-diglycidyl-5- (γ-acetoxy-β-oxy Propyl) isosinurate, sorbitol polyglycidyl ethers, polyglycerol polyglycidyl ethers, pentaerythritol polyglycidyl ethers, diglycerol polyglycidyl ether, 1,3,5-triglycidyl (2-hydroxyethyl) isocyanurate, glycerol poly Epoxy compounds such as glycerol ethers and trimethylolpropane polyglycidyl ethers are preferred, and specific examples of commercially available products include Denacol EX-521 and EX-614B (manufactured by Nagase Chemical Industries). Although it is not intended to be limited thereto.
In order to form the surface layer of the present invention, first, the above polymer, epoxy compound, and appropriate additives are added to and mixed with a solvent such as water (including a dispersant and a binder as necessary). Disperse accordingly) to prepare a surface layer coating solution.
The surface layer is formed by a coating method generally well known on the antistatic layer of the present invention, such as dip coating, air knife coating, curtain coating, wire bar coating, gravure coating, and extrusion coating. It can form by apply | coating the said surface layer coating liquid. The thickness of the surface layer is preferably in the range of 0.01 to 1 μm, more preferably in the range of 0.01 to 0.2 μm. If it is less than 0.01 μm, the anti-detachment function of the conductive metal oxide particles of the antistatic layer is insufficient, and if it exceeds 1 μm, it is difficult to uniformly apply the coating agent, and uneven coating tends to occur on the product.

[Anti-curl layer]
The film of the present invention can be anti-curled. Anti-curl processing gives the function of trying to curl with the surface to which it is applied inside, but by applying this processing, some surface processing is performed on one side of the transparent resin film, It works to prevent curling with the surface facing inward when different degrees and types of surface treatment are applied.
The anti-curl layer may be provided on the side opposite to the side having the anti-glare layer or anti-reflection layer of the base material, or for example, an easy-adhesion layer may be coated on one side of the transparent resin film, and the anti-curl processing is performed on the opposite side. The mode which coats is mentioned.

[Primer layer / Inorganic thin film layer]
In the film of the present invention, gas barrier properties can be enhanced by installing a known primer layer or inorganic thin film layer between the support and the laminate.
As the primer layer, for example, an acrylic resin, an epoxy resin, a urethane resin, a silicone resin, or the like can be used. In the present invention, an organic-inorganic hybrid layer is used as the primer layer, an inorganic vapor deposition layer or a sol-gel is used as the inorganic thin film layer. A dense inorganic coating thin film by the method is preferred. As an inorganic vapor deposition layer, vapor deposition layers, such as a silica, a zirconia, an alumina, are preferable. The inorganic vapor deposition layer can be formed by a vacuum vapor deposition method, a sputtering method, or the like.

[Curing]
After drying the solvent, the film of the present invention can be passed through a zone where the coating film is cured by ionizing radiation and / or heat on the web to cure the coating film.

The ionizing radiation species in the present invention is not particularly limited, and is appropriately selected from ultraviolet rays, electron beams, near ultraviolet rays, visible light, near infrared rays, infrared rays, X-rays and the like according to the type of curable composition forming the film. Although it can be selected, ultraviolet rays and electron beams are preferred, and ultraviolet rays are particularly preferred because they are easy to handle and high energy can be easily obtained.
As the ultraviolet light source for photopolymerizing the ultraviolet reactive compound, any light source that generates ultraviolet light can be used. For example, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, or the like can be used. An ArF excimer laser, a KrF excimer laser, an excimer lamp, synchrotron radiation, or the like can also be used. Among these, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a xenon arc, and a metal halide lamp can be preferably used.

  Moreover, an electron beam can be used similarly. As an electron beam, 50 to 1000 keV, preferably 100 to 100, emitted from various electron beam accelerators such as a cockroft Walton type, a bandegraph type, a resonance transformation type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type. An electron beam having an energy of 300 keV can be given.

Irradiation conditions vary depending on each lamp, but the irradiation light quantity is preferably 10 mJ / cm ² or more, more preferably 50 mJ / cm ^{2 to} 10000 mJ / cm ² , and particularly preferably 50 mJ / cm ^{2 to} 2000 mJ / cm ^2. It is. At that time, the irradiation distribution in the width direction of the web is preferably 50 to 100%, more preferably 80 to 100%, including both ends with respect to the central maximum irradiation.

In the present invention, at least one layer laminated on the support is irradiated with ionizing radiation and heated to a film surface temperature of 60 ° C. or more for 0.5 seconds or more from the start of irradiation with ionizing radiation, with an oxygen concentration of 10 volumes. It is preferable to cure by the step of irradiating ionizing radiation in an atmosphere of less than or equal to%.
It is also preferable to heat in an atmosphere having an oxygen concentration of 3% by volume or less simultaneously and / or continuously with ionizing radiation irradiation.
In particular, it is preferable that the low refractive index layer which is the outermost layer and has a small film thickness is cured by this method. The curing reaction is accelerated by heat, and a film having excellent physical strength and chemical resistance can be formed.

  The time for irradiating with ionizing radiation is preferably from 0.7 seconds to 60 seconds, more preferably from 0.7 seconds to 10 seconds. If it is in said range, hardening reaction can be completed and sufficient hardening can be performed. Further, maintaining the low oxygen condition for a long time is preferable to be within the above range because the equipment becomes large and a large amount of inert gas is required.

  The oxygen concentration is preferably formed by a crosslinking reaction or a polymerization reaction of an ionizing radiation curable compound in an atmosphere of 6% by volume or less, more preferably 4% by volume or less, particularly preferably 2% by volume of oxygen. Hereinafter, it is most preferably 1% by volume or less. Within the above range, the oxygen concentration is not reduced more than necessary, and a large amount of inert gas such as nitrogen is not required, which is preferable from the viewpoint of production cost.

  As a method of reducing the oxygen concentration to 10% by volume or less, it is preferable to replace the atmosphere (nitrogen concentration of about 79% by volume, oxygen concentration of about 21% by volume) with another gas, particularly preferably replacement with nitrogen (nitrogen purge). It is to be.

  In curing, the film surface is preferably heated at 60 ° C. or higher and 170 ° C. or lower. At 60 ° C. or lower, there is little curing by heating, and at 170 ° C. or higher, problems such as deformation of the substrate occur. Furthermore, this preferable temperature is 60 degreeC-100 degreeC. The film surface refers to the film surface temperature of the layer to be cured. The time for the film to reach the temperature is preferably 0.1 second or more and 300 seconds or less from the start of UV irradiation, and more preferably 10 seconds or less. If the time for maintaining the temperature of the film surface in the above temperature range is not less than the above lower limit, the reaction of the curable composition forming the film can be promoted, and if it is not more than the above upper limit, the optical performance of the film does not deteriorate, In addition, production problems such as an increase in equipment do not occur.

  There is no particular limitation on the heating method, but a method of heating a roll to contact the film, a method of spraying heated nitrogen, irradiation with far infrared rays or infrared rays is preferable. A method of heating a rotating metal roll described in Japanese Patent No. 2523574 by flowing a medium such as hot water, steam or oil can also be used. As a heating means, a dielectric heating roll or the like may be used.

  The ultraviolet irradiation may be performed every time one layer is provided for each of a plurality of constituent layers, or may be performed after lamination. Or you may irradiate combining these. From the viewpoint of productivity, it is preferable to irradiate ultraviolet rays after laminating multiple layers.

  In the present invention, when the hard coat layer contains an ultraviolet absorber, ultraviolet irradiation from the side where the hard coat layer is applied reduces the amount of ultraviolet light on the side close to the support due to light absorption by the ultraviolet absorber. As a result, sufficient film strength may not be obtained, or adhesion to the support may not be sufficient. In that case, the adhesiveness with the support can be improved by irradiating light from the support side, which is preferable.

In the present invention, at least one layer laminated on the support can be cured by multiple times of ionizing radiation. In this case, it is preferable that at least two ionizing radiations are performed in a continuous reaction chamber in which the oxygen concentration does not exceed 3% by volume. By performing multiple times of ionizing radiation irradiation in the same low oxygen concentration reaction chamber, the reaction time required for curing can be effectively ensured.
In particular, when the production rate is increased for high productivity, ionizing radiation irradiation is required multiple times to ensure the energy of ionizing radiation necessary for the curing reaction.

  Further, when the curing rate (100-residual functional group content) is a certain value of less than 100%, the lower layer has a curing rate of the upper layer when a layer is provided thereon and cured by ionizing radiation and / or heat. When the height is higher than before, the adhesion between the lower layer and the upper layer is improved, which is preferable.

〔handling〕
In order to continuously produce the film of the present invention, a process of continuously feeding a roll-shaped support film, a process of applying and drying a coating liquid, a process of curing a coating film, and a support film having a cured layer The step of winding is performed.
The film support is continuously sent out from the roll-shaped film support to the clean room. In the clean room, the static electricity charged on the film support is removed by an electrostatic charge-off device, and then the film support adheres on the film support. Remove the foreign material that has been removed with a dust remover. Subsequently, the coating liquid is applied onto the film support in the application section installed in the clean room, and the applied film support is sent to the drying chamber and dried.
The film support having the dried coating layer is fed from the drying chamber to the curing chamber, and the monomer contained in the coating layer is polymerized and cured. Further, the film support having the cured layer is sent to the curing unit to complete the curing, and the film support having the layer having been completely cured is wound up into a roll shape.

The above steps may be performed every time each layer is formed, or a plurality of coating parts-drying chambers-curing parts may be provided to continuously form each layer.
In order to produce the film of the present invention, the coating process in the coating unit and the drying process performed in the drying chamber are performed in a highly clean air atmosphere simultaneously with the microfiltration operation of the coating liquid, and the coating is performed. It is preferable that dust and dust on the film are sufficiently removed before. The air cleanliness of the coating process and the drying process is desirably class 10 (353 particles / 0.5 m or more / (cubic meter) or less) based on the standard of air cleanliness in the US Federal Standard 209E. Preferably, it is preferably class 1 (particles of 0.5 μm or more are 35.5 particles / (cubic meter) or less) or more. Moreover, it is more preferable that the degree of air cleanliness is high also in the feeding and winding parts other than the coating-drying process.

〔Polarizer〕
The polarizing plate of this invention has a polarizer and said polarizing plate protective film of this invention.
Further, it is preferable that the polarizer is sandwiched between the polarizing plate protective film of the present invention and another protective film other than that, and the other protective film has a film mainly composed of a cellulose ester film. .
The other protective film preferably has a viewing angle compensation function. The other protective film preferably has an optically anisotropic layer.
The polarizing plate protective film (optical film) of the present invention constitutes a polarizing plate by being bonded to at least one surface of a polarizer.
The other surface of the polarizer is preferably bonded with another protective film having a moisture permeability of 700 to 3000 g / m ² · day for polarizing plate protection, more preferably 1000 to 1700 g / m ² · day. It is. Ordinarily used triacetyl cellulose (TAC) is preferably used.
A normal cellulose acetate film may be used, but a cellulose acetate film manufactured by a solution casting method and stretched in the width direction in the form of a roll film at a stretching ratio of 10 to 100% may be used.
Furthermore, in the polarizing plate of the present invention, one side may be the polarizing plate protective film of the present invention, while the other protective film may be an optical compensation film having an optically anisotropic layer made of a liquid crystalline compound. .
Further, in the polarizing plate of the present invention, one side is the polarizing plate protective film of the present invention, whereas the other protective film is a film having Re of 0 to 10 nm and Rth of -20 to 20 nm (for example, Japanese Patent Application Laid-Open No. 2005-2005). -301227 (see paragraph number [0095]).

  Examples of the polarizing film include an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine polarizing film and the dye polarizing film are generally produced using a polyvinyl alcohol film.

Of the two protective films of the polarizer, the other protective film is preferably an optical compensation film having an optical compensation layer comprising an optically anisotropic layer. The optical compensation film (retardation film) can improve the viewing angle characteristics of the liquid crystal display screen.
A known film can be used as the optical compensation film, but the optical compensation film described in JP-A-2001-100042 is preferable in terms of widening the viewing angle.

  When the polarizing plate protective film of the present invention is used together with a liquid crystal display device or the like, it is preferably disposed on the viewing side opposite to the liquid crystal cell.

[Liquid Crystal Display]
In the liquid crystal display device of the present invention, at least one of the polarizing plates sandwiching the liquid crystal cell is the polarizing plate of the present invention.
The liquid crystal display device of the present invention preferably further has a brightness enhancement film, and the polarizing plate protective film adjacent to the brightness enhancement film is preferably in close contact.
That is, the film and polarizing plate of the present invention can be advantageously used for an image display device such as a liquid crystal display device, and is preferably used for the outermost layer of the display.
The liquid crystal display device has a liquid crystal cell and two polarizing plates arranged on both sides thereof, and the liquid crystal cell carries a liquid crystal between two electrode substrates. Furthermore, one optically anisotropic layer may be disposed between the liquid crystal cell and one polarizing plate, or two optically anisotropic layers may be disposed between the liquid crystal cell and both polarizing plates. Here, it is preferable that the polarizing plate of this invention is installed only in the visual recognition side.

  The liquid crystal cell is preferably in TN mode, VA mode, OCB mode, IPS mode or ECB mode.

<TN mode>
In the TN mode liquid crystal cell, rod-like liquid crystal molecules are substantially horizontally aligned when no voltage is applied, and are twisted and aligned at 60 to 120 °.
The TN mode liquid crystal cell is most frequently used as a color TFT liquid crystal display device, and is described in many documents.

<VA mode>
In a VA mode liquid crystal cell, rod-like liquid crystal molecules are aligned substantially vertically when no voltage is applied.
The VA mode liquid crystal cell includes (1) a narrowly defined VA mode liquid crystal cell in which rod-like liquid crystalline molecules are aligned substantially vertically when no voltage is applied, and substantially horizontally when a voltage is applied (Japanese Patent Laid-Open No. Hei 2-). 176625) (2) Liquid crystal cell (SID97, Digest of Tech. Papers (Proceedings) 28 (1997) 845 in which the VA mode is converted into a multi-domain (for MVA mode) in order to enlarge the viewing angle. ), (3) A liquid crystal cell in a mode (n-ASM mode) in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied and twisted multi-domain alignment is applied when a voltage is applied (Preliminary collections 58-59 of the Japan Liquid Crystal Society) (1998)) and (4) SURVAVAL mode liquid crystal cells (announced at LCD International 98).

<OCB mode>
The OCB mode liquid crystal cell is a bend alignment mode liquid crystal cell in which rod-like liquid crystal molecules are aligned in substantially opposite directions (symmetrically) at the upper and lower portions of the liquid crystal cell. US Pat. No. 4,583,825, No. 5,410,422. Since the rod-like liquid crystal molecules are symmetrically aligned at the upper and lower portions of the liquid crystal cell, the bend alignment mode liquid crystal cell has a self-optical compensation function. Therefore, this liquid crystal mode is called an OCB (Optically Compensatory Bend) liquid crystal mode. The bend alignment mode liquid crystal display device has an advantage of high response speed.

<IPS mode>
The IPS mode liquid crystal cell is a type in which a nematic liquid crystal is switched by applying a lateral electric field. IDRC (Asia Display '95), p. 577-580 and p. 707-710.

<ECB mode>
In the ECB mode liquid crystal cell, rod-like liquid crystalline molecules are substantially horizontally aligned when no voltage is applied. The ECB mode is one of the liquid crystal display modes having the simplest structure, and is described in detail in, for example, Japanese Patent Application Laid-Open No. 5-203946.

<Brightness enhancement film>
As the brightness enhancement film, a polarization conversion element having a function of separating outgoing light from a light source (backlight) into transmitted polarized light, reflected polarized light, or scattered polarized light is used. Such a brightness enhancement film can improve the output efficiency of linearly polarized light by using retroreflected light from a reflected or scattered polarized backlight.
An example is an anisotropic reflective polarizer. An example of the anisotropic reflective polarizer is an anisotropic multiple thin film that transmits linearly polarized light in one vibration direction and reflects linearly polarized light in the other vibration direction. An example of the anisotropic multi-thin film is DBM manufactured by 3M (see, for example, JP-A-4-268505). An example of the anisotropic reflective polarizer is a composite of a cholesteric liquid crystal layer and a λ / 4 plate. An example of such a composite is PCF manufactured by Nitto Denko (see JP-A-11-231130, etc.). An example of the anisotropic reflective polarizer is a reflective grid polarizer. As a reflective grid polarizer, a metal grid reflective polarizer (see US Pat. No. 6,288,840, etc.) that finely processes metal to produce reflected polarized light even in the visible light region, and metal fine particles in a polymer matrix. And a stretched one (see JP-A-8-184701, etc.).
Moreover, an anisotropic scattering polarizer is mentioned. An example of the anisotropic scattering polarizer is DRP manufactured by 3M (see US Pat. No. 5,825,543).
Furthermore, there is a polarizing element that can perform polarization conversion in one pass. For example, one using a smectic C * can be cited (see JP 2001-201635 A). An anisotropic diffraction grating can be used.
In the case of a liquid crystal display device using a brightness enhancement film, the polarizing plate using the polarizing plate protective film of the present invention is used only for the polarizing plate on the viewing side and is in contact with the brightness enhancement film on the backlight side. The side film is preferably a polarizing plate using a film having both Re and Rth of 300 nm or less. As a result, birefringence interference is suppressed, and rainbow unevenness and color change are greatly improved.
Furthermore, it is more preferable to use a film having Re of 0 to 10 nm and Rth of -30 to 25 nm.
For example, TAC (manufactured by Fujifilm) is preferable as a preferable material, and Z-TAC (manufactured by Fujifilm), O-PET (manufactured by Kanebo), artester film (manufactured by Mitsubishi Gas Chemical) and the like are preferable.
Moreover, when using a brightness enhancement film, it is preferable to adhere the polarizing plate and the brightness enhancement film in order to prevent moisture from entering the polarizing plate and suppress light leakage. The adhesive for bonding the polarizing plate and the brightness enhancement film is not particularly limited. For example, acrylic polymer, silicone polymer, polyester, polyurethane, polyamide, polyvinyl ether, vinyl acetate / vinyl chloride copolymer, modified polyolefin, epoxy-based, fluorine-based, natural rubber, synthetic rubber and other rubber-based polymers Can be appropriately selected and used. In particular, those excellent in optical transparency, exhibiting appropriate wettability, cohesiveness, and adhesive pressure-sensitive adhesive properties and excellent in weather resistance, heat resistance and the like can be preferably used.

<Touch panel>
The film of the present invention can be applied to touch panels described in JP-A-5-127822 and JP-A-2002-48913.

<Organic EL device>
The film of the present invention can be used as a substrate (base film) such as an organic EL element or a protective film.
When the film of the present invention is used for an organic EL device or the like, JP-A-11-335661, JP-A-11-335368, JP-A-2001-192651, JP-A-2001-192652, JP-A-2001-192653, JP-A-2001-335776, JP-A-2001-247859, JP-A-2001-181616, JP-A-2001-181617, JP-A-2002-181816, JP-A-2002-181617, JP-A-2002-056776, etc. The contents described in each publication can be applied. Moreover, it is preferable to use together with the content of each gazette of Unexamined-Japanese-Patent No. 2001-148291, Unexamined-Japanese-Patent No. 2001-221916, and Unexamined-Japanese-Patent No. 2001-231443.

<Measurement method>
Hereinafter, a method for measuring various amounts described in this specification will be described.

[Moisture permeability]
The measurement method of moisture permeability is “Polymer Physical Properties II” (Polymer Experiment Course 4, Kyoritsu Shuppan), pages 285-294: Measurement of vapor permeation amount (mass method, thermometer method, vapor pressure method, adsorption amount method) The film sample of 70 mmφ according to the present invention is conditioned at 60 ° C. and 95% RH for 24 hours, and according to JIS Z-0208, moisture permeability = mass after humidity adjustment−before humidity adjustment The amount of water per unit area (g / m ² ) was calculated by mass.

[Haze]
The total haze (H), internal haze (Hi), and surface haze (Hs) of the obtained film were measured by the following measurements.
[1] The total haze value (H) of the film obtained according to JIS-K7136 was measured.
[2] A few drops of silicone oil are added to the front and back surfaces of the obtained optical film, and two glass plates having a thickness of 1 mm (micro slide glass product number S9111, manufactured by MATSUNAMI) are sandwiched from the front and back to completely Two glass plates and the obtained film were optically adhered, and the haze was measured with the surface haze removed, and the haze measured by sandwiching only silicone oil between two separately measured glass plates. The subtracted value was calculated as the internal haze (Hi) of the film.
[3] A value obtained by subtracting the internal haze (Hi) calculated in the above [2] from the total haze (H) measured in the above [1] was calculated as the surface haze (Hs) of the film.

〔hardness〕
<Pencil hardness>
The strength of the film of the present invention can be evaluated by a pencil hardness test according to JIS-K5400.
The pencil hardness was 2H or higher.

[Adhesion evaluation]
The adhesion between the layers of the film or between the support and the coating layer can be evaluated by the following method.
Nitto Denko Co., Ltd. Polyester adhesive tape with 11 squares and 11 horizontal cuts at 1 mm intervals and a total of 100 squares on the surface of the coated layer. (NO.31B) was pressure-bonded, and the test for peeling off after leaving for 24 hours was repeated three times at the same place, and the presence or absence of peeling was visually observed.
○: peeling is 2 mm or less △: peeling is 2 mm or more and 10 mm or less ×: peeling is 10 mm or more

[Spectral characteristics]
A sample 13 mm × 40 mm was measured for transmittance at a wavelength of 300 to 450 nm with a spectrophotometer (U-3210, Hitachi, Ltd.) at 25 ° C. and 60% RH.
The b value was measured with a SZ-Σ90 color difference meter manufactured by Nippon Denshoku Industries Co., Ltd.

[Reflection]
The liquid crystal display device in which a polarizing plate with an optical film pasted on the surface on the viewing side was subjected to a sensory evaluation of the sense of reflection. The evaluation method is a method in which a plurality of displays are arranged in parallel and relatively compared at the same time. From the front, when the power is turned off and the power is turned on, the blackness (black image) is compared for each film. The level of ○ or higher was regarded as acceptable.
◎: Reflection is not an issue.
○: Reflection can be recognized, but it is hardly anxious.
Δ: Reflection is recognizable and slightly annoying.
×: Reflection is quite worrisome.

[Light resistance]
The prepared polarizing plate is set in an eye super UV tester (metal halide lamp, manufactured by Iwasaki Electric Co., Ltd.), and irradiated with UV light having an intensity of 70 mW / cm ² from the antireflection laminate side for 200 hours. Observed.
○: No color change △: Slightly yellow ×: Yellow

[Evaluation of light leakage after high and low humidity treatment (peripheral unevenness evaluation)]
After the liquid crystal display device is treated at 60 ° C. for 90% for 50 hours or 70 ° C. for 10% for 50 hours and left in an environment of 25 ° C. and 60% for 2 hours, the liquid crystal display device is displayed in black and multiple light leaks from the front Visual evaluation by an observer. ○ The above level was accepted.
◎: No light leakage was observed. ○: Light leakage was hardly noticeable. X: Light leakage was clearly observed.

Hereinafter, the present invention will be described more specifically by way of examples. However, embodiments of the present invention are not limited to these examples.
In the following description, the unit “part” in the description of the amount is “part by mass” unless otherwise specified.

Example 1
[Preparation of polarizing plate protective film]
<Creation of cycloolefin film with easy adhesion layer>
Application to one side of the cycloolefin film 1 (Zeonor film ZF14-100, manufactured by Nippon Zeon Co., Ltd., having a thickness of 100 μm, no solubility in a solvent having a dielectric constant of 10 or more) (the surface serving as an adhesive interface with the easy adhesion layer) Immediately before, a corona discharge treatment was performed, and the following coating solution of S-1 was applied so that the dry film thickness was 90 nm, thereby preparing an easy-adhesion layer (S1). Moreover, the easily bonding layer (S2, S3) was created like S1. However, the dry film thickness of S2 was 0.5 μm, and the dry film thickness of S3 was 30 nm.

――――――――――――――――――――――――――――――――――――――――
Composition of coating liquid S-1 for easy adhesion layer ―――――――――――――――――――――――――――――――――――――――― -
Styrene butadiene latex (solid content 43%) 300 parts by weight 2,4-dichloro-6hydroxy-s-triazine sodium salt (8%) 49 parts by weight Distilled water 1600 parts by weight ――――――――――― ――――――――――――――――――――――――――――

――――――――――――――――――――――――――――――――――――――――
Composition of coating solution S-2 for easy adhesion layer ―――――――――――――――――――――――――――――――――――――――― -
Polytail H 10 parts by mass Toluene 90 parts by mass ―――――――――――――――――――――――――――――――――――――――

――――――――――――――――――――――――――――――――――――――――
Composition of coating solution S-3 for easy adhesion layer ―――――――――――――――――――――――――――――――――――――――― -
APZ6601 100 parts by weight Isopropyl alcohol 67 parts by weight ――――――――――――――――――――――――――――――――――――――――――

The compounds used are shown below.
-Polytail H: Mitsubishi Chemical Corp., terminal hydroxyl polyolefin resin-APZ6601: Nihon Unicar, amino group-containing silicone compound

<Hard coat layer formation>
(Preparation of sol liquid a-1)
A stirrer, a reactor equipped with a reflux condenser, 120 parts of methyl ethyl ketone, 100 parts of acryloxypropyltrimethoxysilane (KBM-5103, manufactured by Shin-Etsu Chemical Co., Ltd.), 3 parts of diisopropoxyaluminum ethyl acetoacetate were added and mixed. After that, 30 parts of ion-exchanged water was added and reacted at 60 ° C. for 4 hours, and then cooled to room temperature to obtain sol liquid a-1.
The mass average molecular weight was 1800, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 100%. From the gas chromatographic analysis, no raw material acryloxypropyltrimethoxysilane remained.

(Preparation of sol liquid a-2)
In a 1,000 ml reaction vessel equipped with a thermometer, a nitrogen inlet tube and a dropping funnel, 187 g (0.80 mol) of acryloxyoxypropyltrimethoxysilane, 27.2 g (0.20 mol) of methyltrimethoxysilane, 320 g of methanol ( 10 mol) and 0.06 g (0.001 mol) of KF were added, and 15.1 g (0.86 mol) of water was slowly added dropwise at room temperature with stirring. After completion of the dropwise addition, the mixture was stirred at room temperature for 3 hours, and then heated and stirred for 2 hours under methanol reflux. Then, 120 g of sol liquid a-2 was obtained by depressurizingly distilling a low boiling point component and further filtering. As a result of GPC measurement of the substance thus obtained, the mass average molecular weight was 1500, and among the components higher than the oligomer component, the component having a molecular weight of 1000 to 20000 was 30%.
Moreover, from the measurement result of 1H-NMR, the structure of the obtained substance was a structure represented by the following formula.

Furthermore, the condensation rate α as measured by 29Si-NMR was 0.56. From this analysis result, it was found that the silane coupling agent sol was mostly composed of a linear structure.
From the gas chromatography analysis, the raw material acryloxypropyltrimethoxysilane had a residual rate of 5% or less.

(Preparation of hollow silica fine particle sol dispersion a)
Hollow silica fine particle sol (Isopropyl alcohol silica sol, average particle diameter 60 nm, shell thickness 10 nm, silica concentration 20% by mass, silica particle refractive index 1.31, created by changing the size according to Preparation Example 4 of JP-A-2002-79616 ) After adding 30 parts of acryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) and 1.5 parts of diisopropoxyaluminum ethyl acetate to 500 parts, 9 parts of ion-exchanged water were added. After reacting at 60 ° C. for 8 hours, the mixture was cooled to room temperature, and 1.8 parts of acetylacetone was added. While adding cyclohexanone to 500 g of this dispersion so that the silica content was almost constant, solvent substitution was performed by distillation under reduced pressure at a pressure of 20 kPa. There was no generation of foreign matter in the dispersion, and the viscosity when the solid content concentration was adjusted to 20% by mass with cyclohexanone was 5 mPa · s at 25 ° C. When the residual amount of isopropyl alcohol in the obtained dispersion a was analyzed by gas chromatography, it was 1.5%.

(1) Preparation of hard coat layer coating solution ───────────────────────────────────
Composition of coating liquid A-1 for hard coat layer ───────────────────────────────────
PET-30 46.0 parts by mass Irgacure 184 1.7 parts by mass P-2 0.06 parts by mass Sol solution a-2 6.0 parts by mass MiBK (methyl isobutyl ketone) 14.0 parts by mass MEK (methyl ethyl ketone) 0 parts by mass ───────────────────────────────────

─――───────────────────────────────────
Composition of coating liquid A-2 for hard coat layer ───――──────────────────────────────────
PET-30 50.0 parts by mass Irgacure 184 2.0 parts by mass SX-350 (30%) 1.5 parts by mass Crosslinked acrylic-styrene particles (30%) 13.0 parts by mass P-2 0.75 parts by mass Sol Liquid a-2 9.5 parts by mass Toluene 38.5 parts by mass ─────――──────────────────────────── ───

───────────────────────────────────
Composition of coating liquid A-3 for hard coat layer ───────────────────────────────────
PET-30 50.0 parts by weight Irgacure 184 2.0 parts by weight Cohesive silica (30%) 15.0 parts by weight P-2 0.06 parts by weight Sol solution a-2 10.0 parts by weight Toluene 38.5 parts by weight ───────────────────────────────────

───────────────────────────────────
Composition of coating solution A-4 for hard coat layer ───────────────────────────────────
Cellulose acetate propionate 3.6 parts by weight Copolyester 2.4 parts by weight Tetrahydrofuran 94 parts by weight ───────────────────────────── ──────

───────────────────────────────────
Composition of coating liquid A-5 for hard coat layer ───────────────────────────────────
Acrylic urethane 36 parts by weight PET-30 24.7 parts by weight DPHA 17.7 parts by weight Methacrylic polymer 21.3 parts by weight Butyl acetate 53.8 parts by weight PMMA fine particles 30 parts by weight Irgacure 907 5 parts by weight F407 0.5 parts by weight n -Butanol 142.13 parts by mass ────────────────────────────────────

───────────────────────────────────
Composition of coating liquid A-6 for hard coat layer ───────────────────────────────────
PET-30 46.0 parts by mass Irgacure 184 1.7 parts by mass P-2 0.06 parts by mass Sol liquid a-2 6.0 parts by mass TINUVIN 328 10.0 parts by mass MiBK (methyl isobutyl ketone) 14.0 parts by mass MEK (methyl ethyl ketone) 5.0 parts by mass───────────────────────────────────

───────────────────────────────────
Composition of coating liquid A-7 for hard coat layer ────────────────────────────――─────
PET-30 50.0 parts by weight Irgacure 184 2.0 parts by weight SX-350 (30%) 1.5 parts by weight Crosslinked acrylic-styrene particles (30%) 13.0 parts by weight P-2 0.75 parts by weight Sol Liquid a-2 9.5 parts by mass TINUVIN327 10.0 parts by mass Toluene 38.5 parts by mass ───────────────────────────── ─ ────

───────────────────────────────────
Composition of coating liquid A-8 for hard coat layer ───────────────────────────────────
PET-30 50.0 parts by weight Irgacure 184 2.0 parts by weight Cohesive silica (30%) 15.0 parts by weight P-2 0.06 parts by weight Sol solution a-2 10.0 parts by weight TINUVIN320 10.0 parts by weight Toluene 38.5 parts by mass───────────────────────────────────

───────────────────────────────────
Composition of coating liquid A-9 for hard coat layer ───────────────────────────────────
Cellulose acetate propionate 3.6 parts by weight Copolyester 2.4 parts by weight TINUVIN 329 1.0 part by weight Tetrahydrofuran 94 parts by weight ─────────────────────── ────────────

───────────────────────────────────
Composition of coating solution A-10 for hard coat layer ───────────────────────────────────
Acrylic urethane 36 parts by weight PET-30 24.7 parts by weight DPHA 17.7 parts by weight Methacrylic polymer 21.3 parts by weight Butyl acetate 53.8 parts by weight PMMA fine particles 30 parts by weight Irgacure 907 5 parts by weight F407 0.5 parts by weight TINUVIN 326 10.0 parts by weight n-butanol 142.13 parts by weight ───────────────────────────────────

  The coating solution was filtered through a polypropylene filter having a pore size of 30 μm to prepare hard coat layer coating solutions A-1 to A-10.

The compounds used are shown below.
PET-30: A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate [manufactured by Nippon Kayaku Co., Ltd.]
・ Irgacure 184: Polymerization initiator [Ciba Specialty Chemicals Co., Ltd.]
SX-350: Cross-linked polystyrene particles having an average particle size of 3.5 μm [refractive index 1.60, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion, used after dispersion at 10,000 rpm for 20 minutes in a Polytron disperser]
Cross-linked acrylic-styrene particles: average particle size 3.5 μm [refractive index 1.55, manufactured by Soken Chemical Co., Ltd., 30% toluene dispersion, used after dispersion at 10,000 rpm for 20 minutes in a Polytron disperser]
P-2: P-2 described in [Chemical Formula 21] of JP-A-2006-206712
-Agglomerated silica: Nippon Silica, agglomerated silica with a secondary particle size of 1.0 μm-Cellulose acetate propionate: Degree of acetylation = 2.5%, Degree of propylation = 46%, polystyrene equivalent number average molecular weight 75000; Eastman, CAP-482-20
-Copolyester: fluorene-modified polyester, OPET; manufactured by Kanebo Co., Ltd., OP7-40
・ THF: Tetrahydrofuran ・ Acrylic urethane: Obtained by reacting the isocyanate group of hydrogenated xylylene diisocyanate with the hydroxyl group of acrylic ester of pentaerythritol ・ DPHA: Mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (Nippon Kayaku Co., Ltd.)
-Methacrylic polymer: Hydroxyethyl group and 2,3-dihydroxypropyl group in the side chain-PMMA fine particles: Average particle size 8.0 μm, refractive index 1.49)
・ Irgacure 907: Polymerization initiator [Ciba Specialty Chemicals Co., Ltd.]
F407: Leveling agent, manufactured by Dainippon Ink and Chemicals, Inc. TINUVIN 320: 2- (3,5-di-t-butyl-2-hydroxyphenyl) benzotriazole, manufactured by Ciba Specialty Chemicals, Inc. TINUVIN 326: 2- ( 3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, manufactured by Ciba Specialty Chemicals, Inc. TINUVIN 327: 2,4-di-t-butyl-6- (5-chlorobenzotriazole) -2-yl-) phenol, manufactured by Ciba Specialty Chemicals, Inc. TINUVIN 328: 2- (3,5-di-t-amyl-2-hydroxyphenyl) benzotriazole, manufactured by Ciba Specialty Chemicals Inc., TINUVIN 329: 2 -(5-t-octyl 2-hydroxyphenyl) benzotriazole, Ciba Specialty Chemicals Inc.

(2) Preparation of coating solution for low refractive index layer ───────────────────────────────────
Preparation of coating solution for low refractive index layer (LL-1) ───────────────────────────────────
Thermally crosslinkable fluorine-containing polymer 3.00 parts by weight Cymel 303 0.75 parts by weight Catalyst 4050 0.07 parts by weight MEK-ST-L 6.4 parts by weight Sol solution a-1 5.8 parts by weight MEK 79.2 Parts by weight cyclohexanone 2.9 parts by weight ────────────────────────────────────

  The refractive index of the layer formed by this coating solution was 1.44.

───────────────────────────────────
Preparation of coating solution for low refractive index layer (LL-2) ───────────────────────────────────
Thermally crosslinkable fluorine-containing polymer 3.44 parts by weight Cymel 303 0.86 parts by weight Catalyst 4050 0.08 parts by weight Hollow silica fine particle sol a 19.5 parts by weight Sol solution a-1 3.4 parts by weight MEK 116.1 Parts by weight cyclohexanone 2.9 parts by weight ───────────────────────────────────

  The refractive index of the layer formed with this coating solution was 1.39.

Each of the above components is as follows.
“Heat-crosslinkable fluorine-containing polymer”: Fluorine-containing silicone-containing thermosetting polymer described in Example 1 of JP-A-11-189621 “Cymel 303”: Curing agent (manufactured by Nippon Cytec Industries, Ltd.)
“Catalyst 4050”: Curing catalyst (manufactured by Nippon Cytec Industries, Ltd.)
“MEK-ST-L”: Colloidal silica dispersion (average particle size 45 nm, solid content 30%, manufactured by Nissan Chemical Co., Ltd.)
"MEK": Methyl ethyl ketone

(2) Coating of hard coat layer The cycloolefin-based film coated with the easy-adhesion layer S1 is unwound in a roll form, and the hard coat layer coating solution A-1 is directly applied to the surface coated with S1. The coating method described in Example 1 of 122889 was applied under the condition of a conveyance speed of 30 m / min, dried at 80 ° C. for 90 seconds, and further under a nitrogen purge, an air-cooled metal halide lamp (Igraphics) Co., Ltd.) was used to cure and wind up the coating layer by irradiating with ultraviolet rays having an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ² . In the application of the hard coat layer coating liquid A-1, the gap G _L between the downstream lip land 18b and the web W was changed to 80 μm, and the degree of vacuum in the vacuum chamber was set to 0.3 kPa. The coating amount was adjusted so that the film thickness of the hard coat layer after curing was the value shown in Table 1.

(3) Coating of low refractive index layer and creation of polarizing plate protective film Cycloolefin film coated with easy-adhesion layer S1 and hard coat layer A-1 is unrolled in roll form and coated with a hard coat layer. The low refractive index layer coating liquid LL-1 was directly applied to the surface using the coating method described in Example 1 of Japanese Patent Application Laid-Open No. 2006-122889 at a conveyance speed of 30 m / min, and dried at 90 ° C. for 120 seconds. Thereafter, it was cured by heating at 120 ° C. for 10 minutes. Further, using a 160 W / cm air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) under a nitrogen purge, the low refractive index layer is cured by irradiating ultraviolet rays with an illuminance of 400 mW / cm ² and an irradiation amount of 250 mJ / cm ^2. The film was wound up to prepare a polarizing plate protective film H1. In the application of the low refractive index layer coating liquid LL-1, the gap G _L between the downstream lip land 18b and the web W was changed to 50 μm, and the degree of vacuum in the vacuum chamber was set to 0.5 kPa. The coating amount was adjusted so that the film thickness of the low refractive index layer after curing was 100 nm.

<Undercoat for polarizer>
Undercoating of the following formulation was performed on the adhesive surface with the polarizer (the surface opposite to the hard coat layer coating surface) to form an easy-adhesion layer and an undercoat layer.

  The opposite surface of the cycloolefin-based film 1 to which S1 was applied was subjected to corona discharge treatment, and the following coating solution was applied (SS1) to a dry film thickness of 90 nm to form an easy adhesion layer.

――――――――――――――――――――――――――――――――――――――――
Composition of coating liquid SS1 for easy adhesion layer ――――――――――――――――――――――――――――――――――――――――
Styrene butadiene latex (solid content 43%) 300 parts by weight 2,4-dichloro-6hydroxy-s-triazine sodium salt (8%) 49 parts by weight Distilled water 1600 parts by weight ――――――――――― ――――――――――――――――――――――――――――

  Further, after coating and drying SS1, a corona discharge treatment is performed on the SS1 coating layer, and the next hydrophilic polymer layer is coated (SS2) to a dry film thickness of 100 nm to form an undercoat layer. As a result, a polarizing plate protective film H1 was obtained. The characteristic was evaluated about the obtained polarizing plate protective film H1. The results are shown in Table 1.

―――――――――――――――――――――――――――――――――――――――
Composition of coating solution SS2 for undercoat layer ――――――――――――――――――――――――――――――――――――――――
Gelatin 30 parts by weight Acetic acid (20%) 20 parts by weight Distilled water 1900 parts by weight ――――――――――――――――――――――――――――――――― ――――――

(Production of polarizer)
A 120 μm-thick polyvinyl alcohol film was immersed in an aqueous solution containing 1 part by mass of iodine, 2 parts by mass of potassium iodide, and 4 parts by mass of boric acid, and stretched 4 times at 50 ° C. to produce a polarizer.

(Other polarizing plate protective film)
In addition, a WV film coated with an optically anisotropic layer (manufactured by FUJIFILM Corporation) was immersed in an aqueous 1.5 mol / L sodium hydroxide solution at 55 ° C. for 120 seconds, and then washed with water and dried.

[Preparation of polarizing plate]
The surface of the polarizing plate protective film H1 on which the SS2 is applied and the surface of the saponified WV film on which the optically anisotropic layer is not applied are combined with 5% of fully saponified polyvinyl alcohol. The aqueous solution was pasted as an adhesive to produce a polarizing plate 1. Further, a polarizing plate T (HT) using a polarizing plate protective film T, that is, a normal TAC (TD80 manufactured by Fuji Film Co., Ltd.) was also prepared instead of the polarizing plate protective film H1. The protective film on the opposite side is a WV film.

[Performance of LCDs]
The polarizing plate provided on the display surface side of the liquid crystal display device (MRT-191S, manufactured by Mitsubishi Electric Corp.) using a TN type liquid crystal cell is peeled off, and the polarizing plate 1 of the present invention is replaced with the cycloolefin-based film surface outside. It was affixed via an adhesive so that the transmission axis of the polarizing plate coincides with the polarizing plate affixed to the product (on the air interface side). Further, the polarizing plate on the backlight side was peeled off, and instead, the polarizing plate T was attached via an adhesive so that the transmission axis of the polarizing plate coincided with the polarizing plate attached to the product. The liquid crystal display device was displayed in a dark room, and the characteristics were evaluated visually from various viewing angles. The results are shown in Table 2.

Examples 2-19, Comparative Examples 1-3
[Preparation of polarizing plate protective film]
(Polarizing plate protective film H2-19)
As shown in Table 1, in place of the polarizing plate protective film H1 of Example 1, the polarizing plate protective films H2 and H3 in which the easy-adhesion layer coating solution was changed to S-2 and S-3, and the hard coat layer coating solution were used. Polarizing plate protective films H4 to H7, H9 to H13 changed to A-2 to A-10, and a polarizing plate protective film H4 coated with a hard coat layer coating solution A-1 in the same manner Polarizing plate protective film H14 obtained by further applying coating solution A-6 for hard coat layer to film H8 and polarizing plate protective film H10 in the same manner, H15 obtained by changing low refractive index layer to LL-2, and coating for hard coat layer H16 prepared in the same manner as H1 except that the liquid was changed to A-4 and no low refractive index layer was provided, H17 prepared in the same manner as H1 except that the easy adhesion layer S1 was not applied, and cycloolefin as a support Film Cellulose triacetate film instead (TD80, Fuji Film Co., Ltd., thickness 80 [mu] m) but using was prepared in the same manner as H1 H18, adhesion layer, creating the H19 not including the hard coat layer and a low refractive index layer. The cellulose triacetate film is soluble in methyl ethyl ketone (relative dielectric constant 18.5), and is soluble in a solvent having a dielectric constant of 10 or more.

The polarizing plate protective films 1 to 16 are polarizing plate protective films of the present invention. On the other hand, the polarizing plate protective films 17 to 19 are polarizing plate protective films as comparative examples.
Table 1 shows the results of the easy adhesion layer, hard coat layer, low refractive index layer, moisture permeability, total haze, surface haze, internal haze, adhesion, and pencil hardness of each polarizing plate protective film 1-19.

[Preparation of polarizing plate]
(Polarizing plate 2-18, Polarizing plate T)
In the same manner as the polarizing plate 1, polarizing plates 2 to 19 were produced using the polarizing plate protective films 2 to 19 instead of the polarizing plate protective film 1.
Further, instead of the polarizing plate protective film 1, a polarizing plate protective film T, that is, a polarizing plate T (HT) using a normal TAC (TD80 manufactured by Fuji Film Co., Ltd.) was also prepared. The protective film on the opposite side is a WV film.

(Polarizing plate WV)
A polarizing plate WV (HWV) was prepared in exactly the same manner as the polarizing plate 1 except that the WV film was a normal TAC (TD80 manufactured by Fuji Film Co., Ltd.).

(Polarizing plate Z)
Polarizing plate Z (HZ) was prepared in exactly the same manner as polarizing plate 1 except that the WV film was low retardation TAC (Z-TAC manufactured by Fuji Film Co., Ltd. Re = 1 nm, Rth = -3 nm).

[Performance of LCDs]
In the same manner as in Example 1, for those using polarizing plates 2 to 19 instead of polarizing plate 1, reflection, light leakage at high and low humidity and light resistance of the viewing side polarizing plate were evaluated (implementation) Examples 1 to 16 and Comparative Examples 1 to 3. See Table 2.)

Further, the polarizing plate provided in the VA type liquid crystal display device (LC-26GD3 manufactured by Sharp) is peeled off while leaving the retardation film, and instead the polarizing plate WV of the present invention has the cycloolefin resin film surface outside ( It was attached to the air interface side) so that the transmission axis of the polarizing plate coincided with the polarizing plate attached to the product.
The polarizing plate provided in the IPS liquid crystal display device (Th-26LX300, manufactured by Matsushita) is peeled off. Instead, the polarizing plate Z of the present invention is placed on the outer side (air interface side) of the cycloolefin-based resin film and the polarizing plate Affixed so that the transmission axis coincided with the polarizing plate affixed to the product.
The polarizing plate provided in the IPS liquid crystal display device (32LC100 manufactured by Toshiba) leaves the retardation film on the front side, peels off the retardation film on the back side, and instead uses the polarizing plate Z of the present invention with the cycloolefin resin film surface. It stuck on the outer side (air interface side) and the transmission axis of the polarizing plate coincided with the polarizing plate stuck on the product.
These were also evaluated for reflection, light leakage at high and low humidity, and light resistance of the viewing side polarizing plate. (Examples 17 to 19. See Table 2.)
In Table 2, for convenience, the polarizing plate 1 using the polarizing plate protective film H1 is indicated as H1. H2 to H19 are also shown in the same manner.

In each Example using polarizing plate 1-16 using polarizing plate protective film 1-16 which is a polarizing plate protective film of this invention, the light leak by high humidity or low humidity does not generate | occur | produce, and a hard-coat layer Thus, it was possible to obtain a polarizing plate protective film, a polarizing plate and a liquid crystal display device having good performance and good surface hardness and good performance.
The polarizing plate protective film H17 obtained by applying the hard coat layer without installing the easy-adhesion layer has poor adhesion, and the polarizing plate 17 using the polarizing plate protective film H17 is of the comparative example 1 using the viewing side. In the liquid crystal display device, the hard coat layer on the viewing side was easily peeled off.
In Comparative Example 2 where the polarizing plate 18 using the polarizing plate protective film H18, which is a polarizing plate protective film having a high moisture permeability and having a solubility in a solvent having a dielectric constant of 10 or more, is used on the viewing side, high humidity or low humidity conditions A light leak occurred.
The polarizing plate protective film H3 obtained without the hard coat layer has a low surface hardness, and the liquid crystal display device of Comparative Example 3 using the polarizing plate 3 using the polarizing plate protective film H3 on the viewing side has a surface hardness. Since it was weak, the display surface of the liquid crystal display device was easily damaged.
In Examples 9 to 14 using polarizing plates 9 to 14 using polarizing plate protective films H9 to H14 obtained by adding an ultraviolet absorber to the hard coat layer, the light resistance of the polarizing plate uses another polarizing plate. It was higher than what I did.
In Example 15 using the polarizing plate 15 using the polarizing plate protective film H15 obtained by installing the low refractive index layer having a refractive index of 1.39, the reflection is lower than the other polarizing plates, so that the reflection is higher. It was good.
In Example 16 using the polarizing plate 16 using the polarizing plate protective film 16 obtained without installing the low refractive index layer, since the reflectance is high, a low refractive index layer having a refractive index of 1.44 is installed. From the results of Examples 1 to 14 obtained in this way, the reflection was slightly visible.
The polarizing plate protective film H1 provided with the easy-adhesive layer S1 has better adhesion than the H2 and H3 provided with the easy-adhesive layers S2 and S3, and the polarizing plate 1 using the polarizing plate protective film H1 is used on the viewing side. In the liquid crystal display device in Example 1, the hard coat layer on the viewing side is more difficult to peel off than the liquid crystal display devices in Examples 2 and 3 in which the polarizing plates 2 and 3 using the polarizing plate protective films H2 and H3 are used on the viewing side. It was.

Examples 20-29, Comparative Examples 4-9
(1) Preparation of hard coat layer coating solution ───────────────────────────────────
Composition of coating solution A-11 for hard coat layer ───────────────────────────────────
PET-30 46.0 parts by mass Irgacure 369 1.7 parts by mass P-2 0.06 parts by mass TINUVIN320 2.5 parts by mass MiBK (methyl isobutyl ketone) 35.0 parts by mass MEK (methyl ethyl ketone) 7.5 parts by mass ──────────────────────────────────

───────────────────────────────────
Composition of coating liquid A-12 for hard coat layer ───────────────────────────────────
PET-30 46.0 parts by mass Irgacure 369 1.7 parts by mass P-2 0.06 parts by mass TINUVIN 328 2.5 parts by mass MiBK (methyl isobutyl ketone) 35.0 parts by mass MEK (methyl ethyl ketone) 7.5 parts by mass ──────────────────────────────────

───────────────────────────────────
Composition of coating solution A-13 for hard coat layer ───────────────────────────────────
PET-30 46.0 parts by mass Irgacure 369 1.7 parts by mass P-2 0.06 parts by mass RUVA-93 2.5 parts by mass MiBK (methyl isobutyl ketone) 35.0 parts by mass MEK (methyl ethyl ketone) 7.5 parts by mass ───────────────────────────────────

───────────────────────────────────
Composition of coating liquid A-14 for hard coat layer ───────────────────────────────────
PET-30 43.5 parts by mass Irgacure 369 1.7 parts by mass P-2 0.06 parts by mass RUVA-93 2.5 parts by mass TINUVIN328 2.5 parts by mass MiBK (methyl isobutyl ketone) 35.0 parts by mass MEK ( Methyl ethyl ketone) 7.5 parts by mass ───────────────────────────────────

───────────────────────────────────
Composition of coating liquid A-15 for hard coat layer ───────────────────────────────────
PET-30 48.5 parts by mass Irgacure 369 1.7 parts by weight P-2 0.06 parts by weight MiBK (methyl isobutyl ketone) 35.0 parts by weight MEK (methyl ethyl ketone) 7.5 parts by weight ─────── ────────────────────────────

  The coating solution was filtered through a polypropylene filter having a pore size of 30 μm to prepare hard coating layer coating solutions A-11 to A-15.

The compounds used are shown below.
RUVA-93: 2- [2′-hydroxy-5 ′-(methacryloyloxy) ethylphenyl] -2H-benzotriazole (trade name, manufactured by Otsuka Chemical Co., Ltd.)

(2) Preparation of coating solution for low refractive index layer ───────────────────────────────────
Preparation of coating solution for low refractive index layer (LL-3) ───────────────────────────────────
Ethylenically unsaturated group-containing fluorine-containing polymer (A-1) 3.9 parts by mass Silica dispersion A (22%) 25.0 parts by mass Irgacure 127 0.2 parts by mass DPHA 0.4 parts by mass MEK 100.0 parts by mass Department MIBK 45.5 parts by mass ────────────────────────────────────

  The coating solution for low refractive index layer was filtered through a polypropylene filter having a pore size of 1 μm to prepare a coating solution. The refractive index after curing of the low refractive index layer obtained by coating and curing the coating solution was 1.36.

The compounds used are shown below.
Ethylenically unsaturated group-containing fluoropolymer (A-1): fluoropolymer (A-1) described in Production Example 3 of JP-A-2005-89536

(Silica dispersion A)
Hollow silica fine particle sol (Isopropyl alcohol silica sol, average particle diameter 60 nm, shell thickness 10 nm, silica concentration 20% by mass, silica particle refractive index 1.31, prepared by changing the size according to Preparation Example 4 of JP-A-2002-79616 ) 10 g of acryloyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) and 1.0 g of diisopropoxyaluminum ethyl acetate were added to and mixed with 500 g, and then 3 g of ion-exchanged water was added. After making it react at 60 degreeC for 8 hours, it cooled to room temperature and added 1.0 g of acetylacetone. While adding cyclohexanone to 500 g of this dispersion so that the content of silica was almost constant, solvent substitution by vacuum distillation was performed. There was no generation of foreign matter in the dispersion, and the viscosity when the solid content concentration was adjusted to 22% by mass with cyclohexanone was 5 mPa · s at 25 ° C. When the residual amount of isopropyl alcohol in the obtained dispersion A was analyzed by gas chromatography, it was 1.0%.

[Preparation of polarizing plate protective film]
As shown in Table 3, in the polarizing plate protective film H1 of Example 1, a sample was prepared by changing the type and thickness of the easy-adhesion layer coating solution, the type and thickness of the hard coat layer, and the type of the low refractive index layer. did. For curing the hard coat layer, in addition to the ultraviolet irradiation from the hard coat layer application surface side in Example 1, irradiation with 250 mJ / cm ² of ultraviolet light was performed from the support surface side under nitrogen purge. The low refractive index layer was cured by omitting the heat curing step at 120 ° C. for 10 minutes under the curing conditions of Example 1.

[Preparation of polarizing plate]
(Polarizing plate 2-18, Polarizing plate T)
A polarizing plate was produced in the same manner as in the production of the polarizing plate 1 except that the polarizing plate protective film 1 shown in Table 4 was used instead of the polarizing plate protective film 1. The obtained polarizing plate was evaluated according to Example 1. In addition to the evaluation of Example 1, the polarizing plate protective film was subjected to the following durability evaluation.

[Haze evaluation after high and low humidity cycle thermoses (cycle thermo evaluation)]
The process of storing the polarizing plate protective film at 90 ° C. for 10 hours, then at 25 ° C. and 55% for 2 hours, then at 70 ° C. and at 10% for 10 hours, and then at 25 ° C. and 55% for 2 hours as one cycle Was repeated four times. The total haze of the polarizing plate protective film was measured before and after passing through this cycle thermo, and the value obtained by subtracting the haze value before thermo from the haze value after thermo (ΔH) was calculated. This ΔH indicates that the closer to zero, the better the durability, and it is preferably 2.0 or less when used in applications requiring durability with large environmental changes during use. More preferably, it is 0 or less.
The evaluation results are shown in Table 4.
In Table 4, the polarizing plate 20 using the polarizing plate protective film H20 is indicated as H20 for convenience. H21 to H35 are also shown in the same manner.

  According to Table 4, it turns out that the polarizing plate protective film which has an easily bonding layer of this invention is excellent in adhesiveness when a hard-coat layer is laminated | stacked. Moreover, it turns out that the polarizing plate of this invention is excellent in a periphery nonuniformity and light resistance, when a hard-coat layer is made to contain a ultraviolet absorber. In addition, if an ultraviolet absorber is added to the hard coat layer, the durability of the polarizing plate protective film when cycle thermo is applied deteriorates. However, when the easy-adhesion layer contains a specific latex or has an polymerizable functional group. It can be seen that this is improved when an absorbent is used.

Claims (9)

  A polarizing plate protective film having a transparent support having no solubility in a solvent having a dielectric constant of 10 or more, a first easy-adhesion layer, and a hard coat layer in this order.   The polarizing plate protective film according to claim 1, wherein the transparent support is a cycloolefin-based film.   The polarizing plate protective film according to claim 1 or 2, wherein the easy-adhesion layer contains at least one selected from acrylic ester latex, methacrylic latex, and styrene latex.   The polarizing plate protective film in any one of Claims 1-3 in which the said hard-coat layer and / or the said easily bonding layer contain a ultraviolet absorber.   The polarizing plate protective film according to any one of claims 1 to 4, wherein the second easy-adhesion layer is provided on the surface of the transparent support opposite to the surface having the hard coat layer.   The polarizing plate protective film according to any one of claims 1 to 5, further comprising an undercoat layer containing a hydrophilic polymer on the easy adhesion layer.   The polarizing plate protective film according to claim 6, wherein the undercoat layer contains an ultraviolet absorber.   The polarizing plate which has a polarizer and the polarizing plate protective film in any one of Claims 1-7.   A liquid crystal display device, wherein at least one of the polarizing plates sandwiching the liquid crystal cell is the polarizing plate according to claim 8.