JP7325333B2 - optically anisotropic film - Google Patents

Description

An optically anisotropic film used as a front plate of a display device, a polarizing plate having the optically anisotropic film, a long polarizing plate made from the polarizing plate, and the optically anisotropic film or the polarizing plate It relates to a display device comprising

2. Description of the Related Art Conventionally, glass has been used as a material for displays of display devices. However, glass has drawbacks such as being fragile and heavy, and does not always have sufficient material properties for thinning, lightening and flexibility in recent years. Therefore, a laminated film obtained by imparting scratch resistance, flexibility, etc. to a resin containing a polyimide polymer has been studied (for example, Patent Document 1).

WO2017/014279

On the other hand, the display device may be viewed while wearing polarized sunglasses, and in such a case, excellent visibility is required even when the screen is viewed through the polarized sunglasses. As a method for improving visibility, a retardation plate is arranged at a predetermined angle on the viewing side of the polarizing plate in order to convert the linearly polarized light emitted from the polarizing plate placed on the viewing side of the display device into elliptically polarized light. There is a need to.
However, according to the studies of the present inventors, if the retardation plate is separately laminated on the laminated film, the flexibility is not sufficient and the thickness cannot be sufficiently reduced. Furthermore, it has been found that when the display device is viewed while wearing polarized sunglasses, the visibility may not be sufficient depending on the angle of the display device.

Accordingly, an object of the present invention is to provide an optically anisotropic film which is thin and has excellent visibility even when viewed through polarized sunglasses on a display device, a polarizing plate having the optically anisotropic film, and a polarizing plate. An object of the present invention is to provide a long polarizing plate and a display device comprising the optical film or the polarizing plate.

As a result of intensive studies to solve the above problems, the present inventors have found that, as a front plate of a display device, an optically anisotropic film containing a polyimide-based polymer is used, and the in-plane of the optically anisotropic film at 550 nm The inventors have found that the above problems can be solved by setting the phase difference within a predetermined range, and have completed the present invention. That is, the present invention includes the following.
[1] An optically anisotropic film used for a front panel of a display device, comprising a polyimide polymer, and having the following formula (1)
80 nm≦Re(550)≦160 nm (1)
[Wherein, Re (550) represents an in-plane retardation at a wavelength of 550 nm]
An optically anisotropic film that satisfies
[2] A polarizing plate comprising the optically anisotropic film of [1] and a polarizing film.
[3] The angle θ1 formed by the slow axis of the optically anisotropic film and the absorption axis of the polarizing film is expressed by the following formula (2)
30°≤θ1≤60° (2)
The polarizing plate according to [2], which satisfies:
[4] The polarizing plate according to [2] or [3], wherein the polarizing film contains a dichroic dye and is composed of an oriented polymer of a polymerizable liquid crystal compound.
[5] The polarizing plate according to any one of [2] to [4], wherein the polarizing film contains a dichroic dye and is made of an oriented polymer of a polymerizable liquid crystal compound having a smectic phase.
[6] The polarizing plate of any one of [2] to [5], comprising an optically anisotropic film, a polarizing film and a second optically anisotropic film laminated in this order.
[7] The second optically anisotropic film is represented by the following formulas (3), (4) and (5)
100 nm≦Re(550)≦160 nm (3)
Re(450)/Re(550)≤1.0 (4)
1.00≦Re(650)/Re(550) (5)
[Wherein, Re (450), Re (550) and Re (650) represent in-plane retardation at wavelengths of 450 nm, 550 nm and 650 nm, respectively]
The polarizing plate according to [6], which satisfies:
[8] The angle θ2 formed between the slow axis of the second optically anisotropic film and the absorption axis of the polarizing film is expressed by the following formula (6)
30°≤θ2≤60° (6)
The polarizing plate of [6] or [7], which satisfies:
[9] A long polarizing plate obtained by making the polarizing plate according to any one of [6] to [8] into a long shape,
Formulas (7), (8) and (9) below
0° ≤ A ≤ 15° or 75° ≤ A ≤ 90° (7)
30°≦B≦60° (8)
0° ≤ C ≤ 15° or 75° ≤ C ≤ 90° (9)
[In the formula, A is the angle between the slow axis of the optically anisotropic film and the major axis direction of the long polarizing plate, and B is the angle between the absorption axis of the polarizing film and the major axis direction of the long polarizing plate. The angle C represents the angle between the slow axis of the second optically anisotropic film and the long axis direction of the long polarizing plate.]
A long polarizing plate that satisfies
[10] A display device comprising the optically anisotropic film of [1] or the polarizing plate of any one of [2] to [9].

The optically anisotropic film of the present invention is thin and has excellent visibility even when the screen is viewed through polarized sunglasses.

[Optical anisotropic film]
The optically anisotropic film of the present invention contains a polyimide polymer, is a film used for the front panel of a display device, and has anisotropy in three-dimensional refractive index. In the present specification, a polyimide-based polymer means a polyimide and a polymer (referred to as polyamideimide) mainly composed of a structural unit containing an imide group and a structural unit containing an amide group. A polyimide-based polymer can be produced, for example, using a tetracarboxylic acid compound and a diamine compound as main raw materials, and in one embodiment of the present invention, the polyimide-based polymer is represented by the following formula (10) It has a repeating structural unit. In formula (10), G is a tetravalent organic group and A is a divalent organic group. In the present invention, the polyimide-based polymer may contain two or more structures represented by formula (10) in which G and/or A are different.

Further, the polyimide polymer may contain one or more structures selected from the structures represented by the following formulas (11) to (13) within a range that does not impair various physical properties of the resulting transparent resin film. good.

In formulas (10) and (11), G and ^G1 each independently represent a tetravalent organic group, preferably a tetravalent organic group having 4 to 40 carbon atoms. The organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group, in which case the hydrocarbon group and the fluorine-substituted hydrocarbon group preferably have 1 to 8 carbon atoms. As G and ^G1 , formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28 ) or a group represented by the formula (29); a group in which hydrogen atoms in the groups represented by those formulas are substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and a tetravalent carbon number Chain hydrocarbon groups of 6 or less are exemplified.

In the above formula, * represents a bond,
Z is a single bond, -O-, -CH ₂ -, -CH ₂ -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, - Ar—, —SO ₂ —, —CO—, —O—Ar—O—, —Ar—O—Ar—, —Ar—CH ₂ —Ar—, —Ar—C(CH ₃ ) ₂ —Ar—, or —Ar—SO ₂ —Ar—. Ar represents an arylene group having 6 to 20 carbon atoms which may be substituted with a fluorine atom, and specific examples include a phenylene group. In the formula (3), Z is preferably a group represented by the formulas (26), (28) and (29) from the viewpoint of easily improving the elastic modulus of the resulting optical film. Further, from the viewpoint of easily reducing the yellowness of the optical film, in formula (3), Y is represented by formula (20), formula (21), formula (22), formula (23), formula (24), formula ( 25), groups represented by formula (26) or formula (27); and groups in which hydrogen atoms in these groups are substituted with methyl, fluoro, chloro or trifluoromethyl groups are preferred. In addition, Z is each independently a single bond, —O—, —CH ₂ —, —CH ₂ —CH ₂ —, —CH(CH ₃ )—, from the viewpoint of easily suppressing the yellowness of the optical film. , -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -, a single bond, -O-, -CH ₂ -, -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -, more preferably -C(CH ₃ ) ₂ - or -C(CF ₃ ) ₂ -, particularly preferably -C(CF ₃ ) ₂ -.

In formula (12), ^G2 represents a trivalent organic group, preferably an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. As ^G2 , the above formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28) or a group in which one of the bonds of the group represented by formula (29) is replaced with a hydrogen atom, and a trivalent chain hydrocarbon group having 6 or less carbon atoms.

In formula (13), ^G3 represents a divalent organic group, preferably an organic group in which a hydrogen atom in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group. As ^G3 , the above formula (20), formula (21), formula (22), formula (23), formula (24), formula (25), formula (26), formula (27), formula (28) Alternatively, a group in which two non-adjacent bonds of the group represented by the formula (29) are replaced with hydrogen atoms, and a chain hydrocarbon group having 6 or less carbon atoms are exemplified.

In formulas (10) to (13), A, A ¹ , A ² and A ³ each independently represent a divalent organic group, preferably a divalent organic group having 4 to 40 carbon atoms. represent. In the organic group, the hydrogen atoms in the organic group may be substituted with a hydrocarbon group or a fluorine-substituted hydrocarbon group, in which case the number of carbon atoms in the hydrocarbon group and the fluorine-substituted hydrocarbon group is preferably is 1-8. As A, A ¹ , A ² and A ³ , the following formula (30), formula (31), formula (32), formula (33), formula (34), formula (35), formula (36), formula (37) or a group represented by the formula (38); a group in which hydrogen atoms in the groups represented by those formulas are substituted with a methyl group, a fluoro group, a chloro group or a trifluoromethyl group; and 6 carbon atoms The following chain hydrocarbon groups are exemplified.

In formulas (30) to (38), * represents a bond,
Z ¹ , Z ² and Z ³ are each independently a single bond, —O—, —CH ₂ —, —CH ₂ —CH ₂ —, —CH(CH ₃ )—, —C(CH ₃ ) ₂ represents -, -C(CF ₃ ) ₂ -, -SO ₂ - or -CO-. The bonding positions of Z ¹ and Z ² to each ring and the bonding positions of Z ² and Z ³ to each ring are preferably meta-positions or para-positions with respect to each ring.

Polyimide-based polymer, for example, can be obtained by polycondensation of a diamine and a tetracarboxylic acid compound (tetracarboxylic dianhydride, etc.), for example, JP-A-2006-199945 or JP-A-2008-163107 can be synthesized according to the method described in Commercial products of polyimide include Neoprim (registered trademark) manufactured by Mitsubishi Gas Chemical Co., Ltd., KPI-MX300F manufactured by Kawamura Sangyo Co., Ltd., and the like.

Tetracarboxylic acid compounds used in the synthesis of polyimide-based polymers include aromatic tetracarboxylic acid compounds such as aromatic tetracarboxylic acids and their anhydrides, preferably their dianhydrides; aliphatic tetracarboxylic acids and their anhydrides. and preferably aliphatic tetracarboxylic acid compounds such as dianhydrides thereof. The tetracarboxylic acid compound may be an anhydride or a derivative of a tetracarboxylic acid compound such as an acid chloride, and these may be used alone or in combination of two or more.

Specific examples of aromatic tetracarboxylic dianhydrides include non-condensed polycyclic aromatic tetracarboxylic dianhydrides, monocyclic aromatic tetracarboxylic dianhydrides and condensed polycyclic aromatic tetracarboxylic dianhydrides. Carboxylic acid dianhydrides are mentioned. Non-fused polycyclic aromatic tetracarboxylic dianhydrides include 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2' , 3,3′-benzophenonetetracarboxylic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,2′,3,3′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxy Phenyl) propane dianhydride, 2,2-bis(3,4-dicarboxyphenoxyphenyl) propane dianhydride, 4,4'-(hexafluoroisopropylidene) diphthalic dianhydride (also referred to as 6FDA ), 1,2-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,2-bis(3,4 -dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3- dicarboxyphenyl)methane dianhydride, 4,4′-(p-phenylenedioxy)diphthalic dianhydride, 4,4′-(m-phenylenedioxy)diphthalic dianhydride. Further, the monocyclic aromatic tetracarboxylic dianhydride includes 1,2,4,5-benzenetetracarboxylic dianhydride, and the condensed polycyclic aromatic tetracarboxylic dianhydride includes 2,3,6,7-naphthalenetetracarboxylic dianhydride.
Among these, preferably 4,4'-oxydiphthalic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2',3,3'-benzophenonetetracarboxylic dianhydride anhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,2′,3,3′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-diphenyl Sulfonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 2,2- Bis(3,4-dicarboxyphenoxyphenyl)propane dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride, 1,2-bis(2,3-dicarboxyphenyl)ethane dianhydride substance, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,2-bis(3,4-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4- dicarboxyphenyl)ethane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, 4,4'-(p-phenylenedioxy ) diphthalic dianhydride and 4,4′-(m-phenylenedioxy)diphthalic dianhydride, more preferably 4,4′-oxydiphthalic dianhydride, 3,3′,4,4 '-biphenyltetracarboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride, bis(3,4 -dicarboxyphenyl)methane dianhydride and 4,4'-(p-phenylenedioxy)diphthalic dianhydride. These can be used individually or in combination of 2 or more types.

Aliphatic tetracarboxylic dianhydrides include cyclic or acyclic aliphatic tetracarboxylic dianhydrides. The cyclic aliphatic tetracarboxylic dianhydride is a tetracarboxylic dianhydride having an alicyclic hydrocarbon structure, and specific examples thereof include 1,2,4,5-cyclohexanetetracarboxylic dianhydride. 1,2,3,4-cyclobutanetetracarboxylic dianhydride, cycloalkanetetracarboxylic dianhydride such as 1,2,3,4-cyclopentanetetracarboxylic dianhydride, bicyclo[2.2 .2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, dicyclohexyl 3,3′-4,4′-tetracarboxylic dianhydride and positional isomers thereof . These can be used singly or in combination of two or more. Specific examples of the acyclic aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride and 1,2,3,4-pentanetetracarboxylic dianhydride. and these can be used alone or in combination of two or more. A cyclic aliphatic tetracarboxylic dianhydride and an acyclic aliphatic tetracarboxylic dianhydride may also be used in combination.

Among the tetracarboxylic acid compounds, the above alicyclic tetracarboxylic dianhydrides or non-condensed polycyclic aromatic tetracarboxylic dianhydrides are preferred from the viewpoint of high transparency and low colorability. Specific examples include 4,4′-oxydiphthalic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, and 3,3′,4,4′-biphenyltetracarboxylic dianhydride. 2,2′,3,3′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, 2,2-bis(3,4-di Carboxyphenyl)propane dianhydride, 4,4′-(hexafluoroisopropylidene)diphthalic dianhydride and mixtures thereof are preferred, 3,3′,4,4′-biphenyltetracarboxylic dianhydride and 4 ,4'-(hexafluoroisopropylidene)diphthalic dianhydride and mixtures thereof are more preferred, and 4,4'-(hexafluoroisopropylidene)diphthalic dianhydride is even more preferred.

In the present invention, the polyimide-based polymer is a combination of a tricarboxylic acid compound and a dicarboxylic acid compound in addition to the tetracarboxylic acid compound used in the polyimide synthesis, as long as the various physical properties of the resulting transparent resin film are not impaired. may be used as

Examples of tricarboxylic acid compounds include aromatic tricarboxylic acids, aliphatic tricarboxylic acids, and derivatives thereof (e.g., acid chlorides, acid anhydrides, etc.). Specific examples include 1,2,4-benzenetricarboxylic acid. anhydride; 2,3,6-naphthalenetricarboxylic acid-2,3-anhydride; single bond between phthalic anhydride and benzoic acid, —O—, —CH ₂ —, —C(CH ₃ ) ₂ —, Compounds linked by —C(CF ₃ ) ₂ —, —SO ₂ — or phenylene groups can be mentioned. These tricarboxylic acid compounds can be used alone or in combination of two or more.

Examples of dicarboxylic acid compounds include aromatic dicarboxylic acids, aliphatic dicarboxylic acids and derivatives thereof (e.g., acid chlorides, acid anhydrides, etc.). Specific examples include terephthalic acid; isophthalic acid; naphthalenedicarboxylic acid; 4,4'-biphenyldicarboxylic acid; 3,3'-biphenyldicarboxylic acid; a chain hydrocarbon having 8 or less carbon atoms, a dicarboxylic acid compound of and two benzoic acids are single bonds, -O-, -CH ₂ -, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -SO ₂ -, or compounds linked by a phenylene group. These tricarboxylic acid compounds can be used alone or in combination of two or more.

Aliphatic diamines, aromatic diamines, or mixtures thereof may be used as the diamine compound used in synthesizing the polyimide. As used herein, the term "aromatic diamine" refers to a diamine compound in which an amino group is directly bonded to an aromatic ring, and may contain an aliphatic group or other substituents in part of its structure. . The aromatic ring may be a single ring or a condensed ring, and examples include, but are not limited to, benzene ring, naphthalene ring, anthracene ring and fluorene ring. Among these, a benzene ring is preferred. In addition, "aliphatic diamine" represents a diamine compound in which an amino group is directly bonded to an aliphatic group, and may contain an aromatic ring or other substituents in part of its structure.

Aliphatic diamines include, for example, acyclic aliphatic diamines such as hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, norbornanediamine, 4,4'- Cycloaliphatic diamines such as diaminodicyclohexylmethane and the like can be mentioned, and these can be used alone or in combination of two or more.

Specific examples of aromatic diamines include p-phenylenediamine, m-phenylenediamine, 2,4-toluenediamine, m-xylylenediamine, p-xylylenediamine, 1,5-diaminonaphthalene, 2,6-diamino Aromatic diamines having one aromatic ring such as naphthalene; 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3 '-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis (4-aminophenoxy)benzene, 4,4'-diaminodiphenylsulfone, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis [4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2'-dimethylbenzidine, 2,2'-bis(trifluoromethyl) -4,4'-diaminodiphenyl (sometimes referred to as TFMB), 4,4'-bis(4-aminophenoxy)biphenyl, 9,9-bis(4-aminophenyl)fluorene, 9,9-bis (4-amino-3-methylphenyl) fluorene, 9,9-bis(4-amino-3-chlorophenyl) fluorene, 9,9-bis(4-amino-3-fluorophenyl) fluorene, etc., aromatic rings Aromatic diamines having two or more are mentioned. These can be used individually or in combination of 2 or more types.

Among the above diamine compounds, it is preferable to use one or more selected from the group consisting of aromatic diamines having a biphenyl structure from the viewpoint of high transparency and low coloration. from 2,2'-dimethylbenzidine, 2,2'-bis(trifluoromethyl)-4,4'-diaminodiphenyl, 4,4'-bis(4-aminophenoxy)biphenyl and 4,4'-diaminodiphenyl ether More preferably, one or more selected from the group consisting of 2,2′-bis(trifluoromethyl)-4,4′-diaminodiphenyl is used.

The polyimide-based polymer includes a diamine, a tetracarboxylic acid compound (an acid chloride compound, a tetracarboxylic acid compound derivative such as a tetracarboxylic dianhydride), and optionally a tricarboxylic acid compound (an acid chloride compound, a tricarboxylic acid anhydride At least one compound selected from the group consisting of tricarboxylic acid compound derivatives such as (tricarboxylic acid compound derivatives such as acid chloride compounds) and dicarboxylic acid compounds (dicarboxylic acid compound derivatives such as acid chloride compounds). A repeating structural unit represented by formula (11) is usually derived from a diamine and a tetracarboxylic acid compound. A repeating structural unit represented by formula (12) is usually derived from a diamine and a tricarboxylic acid compound. A repeating structural unit represented by formula (13) is usually derived from a diamine and a dicarboxylic acid compound. Specific examples of diamines, tetracarboxylic acid compounds, dicarboxylic acid compounds, and tricarboxylic acid compounds are as described above.

The polyimide-based polymer may be a copolymer containing different types of repeating structural units described above. The polyimide polymer has a standard polystyrene equivalent weight average molecular weight of 50,000 or more, preferably 200,000 or more, more preferably 300,000 or more, still more preferably 350,000 or more, preferably 750,000. Below, more preferably 600,000 or less, still more preferably 500,000 or less. When the weight average molecular weight of the polyimide polymer is at least the above lower limit, the flexibility of the optical film containing the polyimide polymer tends to be improved, and the weight average molecular weight of the polyimide resin is at the above upper limit. When it is below, the viscosity of the polyamide-imide varnish can be kept low, and the optical film can be easily stretched, resulting in good workability. In this specification, the weight average molecular weight can be determined by, for example, GPC measurement and standard polystyrene conversion. Specifically, it can be determined by the method described in Examples.

The polyimide-based polymer may contain halogen atoms such as fluorine atoms that can be introduced by the fluorine-based substituents described above. By including a halogen atom in the polyimide polymer, the elastic modulus of the optically anisotropic film can be improved and the yellowness can be reduced. As a result, scratches, wrinkles, and the like occurring in the optically anisotropic film can be suppressed, and the transparency of the optically anisotropic film can be improved. A halogen atom is preferably a fluorine atom.
The content of halogen atoms in the polyimide polymer is preferably 1 to 40% by mass, more preferably 5 to 35% by mass, based on the mass of the polyimide polymer.

In the present invention, the content of the polyimide polymer contained in the optically anisotropic film is preferably 40% by mass or more, more preferably 60% by mass or more, and still more preferably 80% by mass, relative to the mass of the optical film. or more, and may be 100% by mass. When the content of the polyimide polymer is at least the above lower limit, the optically anisotropic film has good flexibility.

The optically anisotropic film of the present invention has the following formula (1)
80 nm≦Re(550)≦160 nm (1)
[Wherein, Re (550) represents an in-plane retardation at a wavelength of 550 nm]
meet. Since the optically anisotropic film of the present invention has such an in-plane retardation, it has excellent visibility even when a display device including the optically anisotropic film is viewed through polarized sunglasses. For example, even when the angle of the display device is changed while wearing polarized sunglasses, disturbance of display hue is suppressed or prevented, and excellent visibility can be exhibited. Moreover, in the present invention, since the optically anisotropic film used for the front panel of the display device is provided with a predetermined retardation, the film can be made thinner without providing a separate retardation film. Furthermore, since the polyimide polymer is included, the bendability (or flexibility) is good, and coloration or the like during bending is suppressed. In this specification, visibility refers to the degree of ease of viewing display on a display device, and improved visibility means that display on a display device is easier to see. Note that Re(550) can be measured using a phase difference measuring device, for example, by the method described in Examples.

The formula (1) preferably satisfies 100 nm≦Re(550)≦160 nm, more preferably 130 nm≦Re(550)≦150 nm. If the range of the formula (1) is exceeded, a problem may occur that the hue of the front of the display device becomes black, red, or blue.

The optically anisotropic film of the invention can contain an ultraviolet absorber. The ultraviolet absorber can be appropriately selected from commonly used ultraviolet absorbers. The ultraviolet absorber may contain a compound that absorbs light with a wavelength of 400 nm or shorter. Examples of UV absorbers that can be appropriately combined with polyimide-based polymers include at least one compound selected from the group consisting of benzophenone-based compounds, salicylate-based compounds, benzotriazole-based compounds, and triazine-based compounds. . As used herein, a "based compound" refers to a derivative of the compound to which the "based compound" is attached. For example, a "benzophenone-based compound" refers to a compound having benzophenone as a parent skeleton and a substituent attached to the benzophenone.

The content of the ultraviolet absorber is not particularly limited as long as it is an amount that does not impair visibility, transparency, flexibility, etc., and is usually 1% by mass or more relative to the total mass of the optically anisotropic film. , preferably 2% by mass or more, more preferably 3% by mass or more, usually 10% by mass or less, preferably 8% by mass or less, and more preferably 6% by mass or less .

The optically anisotropic film of the invention can contain an inorganic material. The inorganic material is preferably a silicon material containing silicon atoms. When the optically anisotropic film contains an inorganic material such as a silicon material, a particularly excellent effect in terms of flexibility can be obtained. Silicon materials containing silicon atoms include silica particles, quaternary alkoxysilanes such as tetraethyl orthosilicate (TEOS), silicon compounds such as silsesquioxane derivatives, and the like. Among these silicon materials, silica particles are preferred from the viewpoint of transparency and flexibility of the optically anisotropic film.

When the optically anisotropic film of the present invention contains an inorganic material, the compounding ratio of the polyimide-based polymer and the inorganic material is 1:9 to 10:0 in mass ratio, where the total of both is 10. It is preferably from 3:7 to 10:0, even more preferably from 3:7 to 8:2, and particularly preferably from 3:7 to 7:3. The ratio of the inorganic material to the total mass of the polyimide polymer and the inorganic material is usually 20% by mass or more, preferably 30% by mass or more, usually 90% by mass or less, and 70% by mass or less. is preferred. When the compounding ratio of the polyimide-based polymer and the inorganic material is within the above range, the transparency and mechanical strength of the optically anisotropic film tend to be improved.

The optically anisotropic film may further contain other additives as long as they do not significantly impair the transparency and flexibility. Other additives include, for example, antioxidants, release agents, stabilizers, colorants such as bluing agents, flame retardants, lubricants and leveling agents. When the optically anisotropic film contains other additives, the content of the other additives is preferably more than 0% and 20% by mass or less with respect to the mass of the optically anisotropic film. More preferably, it exceeds 0% and is 10% by mass or less.

The thickness of the optically anisotropic film can be appropriately selected according to the display device to which it is applied. More preferably, it is 20 to 100 μm.

At least one surface of the optically anisotropic film may be subjected to surface treatment such as UV ozone treatment, plasma treatment, or corona discharge treatment.

In one embodiment of the present invention, the optically anisotropic film of the present invention is prepared by coating a substrate (sometimes referred to as a support) with a polymer varnish obtained by dissolving a polymer containing the polyimide polymer in a solvent. After forming a coating film with the above method, the coating film is dried to obtain a polymer film with a support (1), the support is peeled from the obtained polymer film with a support to obtain a polymer film (2), and It can be produced by a method including the step (3) of stretching the obtained polymer film.

In step (1), the solvent for dissolving the polymer may be any solvent capable of dissolving the polymer, such as dimethylformacetamide (DMAC), dimethylformamide (DMF), dimethylsulfoxide (DMSO), γ-butyrolactone (GBL ), and mixed solvents thereof. Moreover, the support is not particularly limited, and a polyethylene terephthalate (PET) support, a stainless steel (SUS) belt, a glass substrate, or the like can be preferably used.

Examples of coating methods include known coating methods such as wire bar coating, reverse coating, roll coating such as gravure coating, die coating, comma coating, lip coating, spin coating, screen coating, fountain coating, A dipping method, a spray method, a casting method, and the like can be mentioned. The coating film can be dried by heating, and the heating temperature is usually 50 to 350°C, preferably 50 to 150°C. The solvent can be evaporated and removed by heating the coating film.

In step (3), the polymer film may be uniaxially stretched or biaxially stretched, but uniaxially stretching is preferred. The optically anisotropic film of the present invention can be obtained by stretching the polymer film obtained in steps (1) and (2) so as to satisfy the relationship of formula (1). The draw ratio is preferably 1.005 to 2.0 times, more preferably 1.01 to 1.5 times, still more preferably 1.01 to 1.1 times. The stretching temperature is preferably 100-300°C, more preferably 150-250°C. Examples of the stretching method include a stretching method between rolls and a compression stretching method.

[Polarizer]
The polarizing plate of the present invention has the optically anisotropic film and the polarizing film.

[Polarizing film]
A polarizing film is a film having a polarizing function. The polarizing film may be a stretched film to which a dichroic dye is adsorbed, but from the viewpoint of thinning, a polymerizable liquid crystal compound containing a dichroic dye (hereinafter referred to as a polymerizable liquid crystal compound (B) It is preferable that the film is made of an oriented polymer. The polarizing film can be obtained by polymerizing a polymerizable liquid crystal composition (hereinafter sometimes referred to as polymerizable liquid crystal composition B) containing the polymerizable liquid crystal compound (B) in an aligned state.

The liquid crystal state exhibited by the polymerizable liquid crystal compound (B) is preferably a smectic phase (smectic liquid crystal state). A second smectic liquid crystal state) is more preferred.
High order smectic phase means smectic B phase, smectic D phase, smectic E phase, smectic F phase, smectic G phase, smectic H phase, smectic I phase, smectic J phase, smectic K phase and smectic L phase, Among these, smectic B phase, smectic F phase and smectic I phase are more preferable. A polarizing film with a high degree of orientational order provides a Bragg peak derived from a higher-order structure such as a hexatic phase or a crystal phase in X-ray diffraction measurement. A Bragg peak means a peak derived from a plane periodic structure of molecular orientation, and a polarizing film having a periodic interval of 3.0 to 6.0 Å is preferred.

A polymerizable liquid crystal compound (B) having a smectic phase is called a polymerizable smectic liquid crystal compound. Polymerizable smectic liquid crystal compounds include compounds represented by Formula (B).
U ¹ -V ¹ -W ¹ -X ¹ -Y ¹ -X ² -Y ² -X ³ -W ² -V ² -U ² (B)
[In formula (B),
X ¹ , X ² and X ³ each independently represent an optionally substituted 1,4-phenylene group or an optionally substituted cyclohexane-1,4-diyl group. However, at least one of X ¹ , X ² and X ³ is an optionally substituted 1,4-phenylene group. —CH ₂ — constituting a cyclohexane-1,4-diyl group may be replaced with —O—, —S— or —NR—. R represents an alkyl group having 1 to 6 carbon atoms or a phenyl group.
Y ¹ and Y ² are independently of each other -CH ₂ CH ₂ -, -CH ₂ O-, -COO-, -OCOO-, single bond, -N=N-, -CR ^a =CR ^b -, - represents C≡C— or CR ^a =N—; R ^a and R ^b each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
U ¹ represents a hydrogen atom or a polymerizable group.
^U2 represents a polymerizable group.
W ¹ and W ² each independently represent a single bond, -O-, -S-, -COO- or OCOO-.
V ¹ and V ² each independently represent an optionally substituted alkanediyl group having 1 to 20 carbon atoms, and —CH ₂ — constituting the alkanediyl group is —O—, — It may be substituted with S- or NH-. ]

At least two of X ¹ , X ² and X ³ are preferably optionally substituted 1,4-phenylene groups.

The optionally substituted 1,4-phenylene group is preferably unsubstituted. Optionally substituted cyclohexane-1,4-diyl group is preferably optionally substituted trans-cyclohexane-1,4-diyl group, The trans-cyclohexane-1,4-diyl group which may have is preferably unsubstituted.

The optionally substituted 1,4-phenylene group or optionally substituted cyclohexane-1,4-diyl group may have a methyl group, an ethyl group, Examples include alkyl groups having 1 to 4 carbon atoms such as butyl groups, cyano groups and halogen atoms.

Y ¹ is preferably -CH ₂ CH ₂ -, -COO- or a single bond, and Y ² is preferably -CH ₂ CH ₂ - or CH ₂ O-.

^U2 is a polymerizable group. U ¹ is a hydrogen atom or a polymerizable group, preferably a polymerizable group. Both U ¹ and U ² are preferably polymerizable groups, preferably photopolymerizable groups. A photopolymerizable group means a group that can participate in a polymerization reaction by an active radical or an acid generated from a photopolymerization initiator, which will be described later.

The photopolymerizable group represented by ^U1 and the polymerizable group represented by ^U2 may be different from each other, but are preferably of the same type. Polymerizable groups include vinyl, vinyloxy, 1-chlorovinyl, isopropenyl, 4-vinylphenyl, acryloyloxy, methacryloyloxy, oxiranyl and oxetanyl groups. Among them, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group and an oxetanyl group are preferred, and an acryloyloxy group is more preferred.

The alkanediyl groups represented by V ¹ and V ² include methylene group, ethylene group, propane-1,3-diyl group, butane-1,3-diyl group, butane-1,4-diyl group, pentane- 1,5-diyl group, hexane-1,6-diyl group, heptane-1,7-diyl group, octane-1,8-diyl group, decane-1,10-diyl group, tetradecane-1,14-diyl and icosane-1,20-diyl groups. V ¹ and V ² are preferably alkanediyl groups having 2 to 12 carbon atoms, more preferably alkanediyl groups having 6 to 12 carbon atoms.

Examples of substituents optionally possessed by the alkanediyl group include a cyano group and a halogen atom, but the alkanediyl group is preferably unsubstituted, and is an unsubstituted and linear alkanediyl group. is more preferred.

W ¹ and W ² are each independently preferably a single bond or O—.

Examples of the compound represented by formula (B) include compounds represented by formulas (B-1) to (B-25). When the compound represented by formula (B) above has a cyclohexane-1,4-diyl group, the cyclohexane-1,4-diyl group is preferably in the trans form.

Among these, formula (B-2), formula (B-3), formula (B-4), formula (B-5), formula (B-6), formula (B-7), formula (B- 8), at least one selected from the group consisting of compounds represented by formula (B-13), formula (B-14), formula (B-15), formula (B-16) and formula (B-17) Seeds are preferred.

The exemplified polymerizable liquid crystal compound (B) can be used alone or in combination. When combining two or more polymerizable liquid crystal compounds, at least one is preferably the polymerizable liquid crystal compound (B), and more preferably two or more are the polymerizable liquid crystal compounds (B). By combining them, it may be possible to temporarily maintain the liquid crystallinity even at a temperature below the liquid crystal-crystal phase transition temperature. The mixing ratio when two types of polymerizable liquid crystal compounds are combined is usually 1:99 to 50:50, preferably 5:95 to 50:50, more preferably 10:90 to 50:50. is.

The polymerizable liquid crystal compound (B) is described, for example, in Lub et al. Recl. Trav. Chim. Pays-Bas, 115, 321-328 (1996), or a known method described in Japanese Patent No. 4,719,156.

The content of the polymerizable liquid crystal compound (B) in the polymerizable liquid crystal composition B constituting the polarizing film is preferably 70 to 99.9% by mass, more preferably 80 to 99.9%, based on the solid content of the composition. % by mass is more preferred. If the content of the polymerizable liquid crystal compound (B) is within the above range, the orientation of the polymerizable liquid crystal compound (B) tends to be high. In the present specification, the solid content refers to the total amount of components of the polymerizable liquid phase composition B excluding volatile components such as solvents.

The polymerizable liquid phase composition B that constitutes the polarizing film contains a dichroic dye. A dichroic dye means a dye having a property that the absorbance in the long axis direction and the absorbance in the short axis direction of the molecule are different. The dichroic dye is not limited as long as it has such properties, and may be a dye or a pigment. Two or more dyes may be used in combination, two or more pigments may be used in combination, or a dye and a pigment may be used in combination.

The dichroic dye preferably has a maximum absorption wavelength (λ _MAX ) in the range of 300-700 nm. Examples of such dichroic dyes include acridine dyes, oxazine dyes, cyanine dyes, naphthalene dyes, azo dyes and anthraquinone dyes, with azo dyes being preferred. The azo dyes include monoazo dyes, bisazo dyes, trisazo dyes, tetrakisazo dyes and stilbenazo dyes, with bisazo dyes and trisazo dyes being preferred.

Examples of azo dyes include compounds represented by formula (I) (hereinafter sometimes referred to as "compound (I)").
K ¹ (-N=N-K ² ) _p -N=N-K ³ (I)
[In formula (I), K ¹ and K ³ are each independently a phenyl group optionally having a substituent, a naphthyl group optionally having a substituent, or a represents a good monovalent heterocyclic group. K ² is a p-phenylene group optionally having substituents, a naphthalene-1,4-diyl group optionally having substituents or a divalent heterocyclic ring optionally having substituents represents a group.
p represents an integer of 1 to 4; When p is an integer of 2 or more, multiple ^K2 may be the same or different. ]

Examples of monovalent heterocyclic groups include groups obtained by removing one hydrogen atom from heterocyclic compounds such as quinoline, thiazole, benzothiazole, thienothiazole, imidazole, benzimidazole, oxazole, and benzoxazole. The divalent heterocyclic group includes a group obtained by removing two hydrogen atoms from the above heterocyclic compound.

As a substituent optionally possessed by a phenyl group, a naphthyl group and a monovalent heterocyclic group for K ¹ and K ³ , and a p-phenylene group, a naphthalene-1,4-diyl group and a divalent heterocyclic group for K ² is an alkyl group having 1 to 4 carbon atoms; an alkoxy group having 1 to 4 carbon atoms such as a methoxy group, an ethoxy group and a butoxy group; a fluorinated alkyl group having 1 to 4 carbon atoms such as a trifluoromethyl group; a cyano group; Nitro group; halogen atom; amino group, diethylamino group, substituted or unsubstituted amino group such as pyrrolidino group (substituted amino group is an amino group having one or two alkyl groups having 1 to 6 carbon atoms, or two It means an amino group in which substituted alkyl groups are bonded together to form an alkanediyl group having 2 to 8 carbon atoms, and an unsubstituted amino group is —NH ₂ .).

［式（Ｉ－１）～（Ｉ－６）中、
Ｂ^１～Ｂ^２０は、互いに独立に、水素原子、炭素数１～６のアルキル基、炭素数１～４のアルコキシ基、シアノ基、ニトロ基、置換又は無置換のアミノ基（置換アミノ基及び無置換アミノ基の定義は前記のとおり）、塩素原子又はトリフルオロメチル基を表わす。
ｎ１～ｎ４は、互いに独立に０～３の整数を表わす。
ｎ１が２以上である場合、複数のＢ^２は互いに同一でも異なっていてもよく、
ｎ２が２以上である場合、複数のＢ^６は互いに同一でも異なっていてもよく、
ｎ３が２以上である場合、複数のＢ^９は互いに同一でも異なっていてもよく、
ｎ４が２以上である場合、複数のＢ¹⁴は互いに同一でも異なっていてもよい。］Among compounds (I), compounds represented by any one of the following formulas (I-1) to (I-6) are preferred.

[In the formulas (I-1) to (I-6),
B ¹ to B ²⁰ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a cyano group, a nitro group, a substituted or unsubstituted amino group (substituted amino group and The definition of an unsubstituted amino group is as described above), it represents a chlorine atom or a trifluoromethyl group.
n1 to n4 each independently represents an integer of 0 to 3;
When n1 is 2 or more, the plurality of ^B2 may be the same or different,
When n2 is 2 or more, the plurality of ^B6 may be the same or different,
When n3 is 2 or more, multiple ^B9 may be the same or different,
When n4 is 2 or more, the plurality of B ¹⁴ may be the same or different. ]

［式（Ｉ－７）中、
Ｒ^１～Ｒ^８は、互いに独立に、水素原子、－Ｒ^ｘ、－ＮＨ_２、－ＮＨＲ^ｘ、－ＮＲ^ｘ _２、－ＳＲ^ｘ又はハロゲン原子を表わす。
Ｒ^ｘは、炭素数１～４のアルキル基又は炭素数６～１２のアリール基を表わす。］As the anthraquinone dye, a compound represented by formula (I-7) is preferable.

[In the formula (I-7),
R ¹ to R ⁸ each independently represent a hydrogen atom, —R ^x , —NH ₂ , —NHR ^x , —NR ^x ₂ , —SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

［式（Ｉ－８）中、
Ｒ^９～Ｒ^１５は、互いに独立に、水素原子、－Ｒ^ｘ、－ＮＨ_２、－ＮＨＲ^ｘ、－ＮＲ^ｘ _２、－ＳＲ^ｘ又はハロゲン原子を表わす。
Ｒ^ｘは、炭素数１～４のアルキル基又は炭素数６～１２のアリール基を表わす。］As the oxazone dye, a compound represented by formula (I-8) is preferable.

[In the formula (I-8),
R ⁹ to R ¹⁵ each independently represent a hydrogen atom, —R ^x , —NH ₂ , —NHR ^x , —NR ^x ₂ , —SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]

［式（Ｉ－９）中、
Ｒ^１６～Ｒ^２３は、互いに独立に、水素原子、－Ｒ^ｘ、－ＮＨ_２、－ＮＨＲ^ｘ、－ＮＲ^ｘ _２、－ＳＲ^ｘ又はハロゲン原子を表わす。
Ｒ^ｘは、炭素数１～４のアルキル基又は炭素数６～１２のアリール基を表わす。］
式（Ｉ－７）、式（Ｉ－８）及び式（Ｉ－９）において、Ｒ^ｘの炭素数１～６のアルキル基としては、メチル基、エチル基、プロピル基、ブチル基、ペンチル基及びヘキシル基が挙げられ、炭素数６～１２のアリール基としては、フェニル基、トルイル基、キシリル基及びナフチル基が挙げられる。As the acridine dye, a compound represented by formula (I-9) is preferable.

[In the formula (I-9),
R ¹⁶ to R ²³ each independently represent a hydrogen atom, —R ^x , —NH ₂ , —NHR ^x , —NR ^x ₂ , —SR ^x or a halogen atom.
R ^x represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 12 carbon atoms. ]
In formula (I-7), formula (I-8) and formula (I-9), the alkyl group having 1 to 6 carbon atoms for R ^x includes a methyl group, an ethyl group, a propyl group, a butyl group and a pentyl group. and hexyl groups, and examples of aryl groups having 6 to 12 carbon atoms include phenyl, toluyl, xylyl and naphthyl groups.

［式（Ｉ－１０）中、
Ｄ^１及びＤ^２は、互いに独立に、式（Ｉ－１０ａ）～式（Ｉ－１０ｄ）のいずれかで表される基を表わす。

ｎ５は１～３の整数を表わす。］

［式（Ｉ－１１）中、
Ｄ^３及びＤ^４は、互いに独立に、式（Ｉ－１１ａ）～式（Ｉ－１１ｈ）のいずれかで表される基を表わす。

ｎ６は１～３の整数を表わす。］As the cyanine dye, a compound represented by formula (I-10) and a compound represented by formula (I-11) are preferable.

[In the formula (I-10),
D ¹ and D ² each independently represent a group represented by any one of formulas (I-10a) to (I-10d).

n5 represents an integer of 1-3. ]

[In the formula (I-11),
D ³ and D ⁴ each independently represent a group represented by any one of formulas (I-11a) to (I-11h).

n6 represents an integer of 1-3. ]

The content of the dichroic dye in the polymerizable liquid crystal composition B constituting the polarizing film can be appropriately adjusted according to the type of the dichroic dye, etc. It is preferably 0.1 to 50 parts by mass, more preferably 0.1 to 20 parts by mass, even more preferably 0.1 to 10 parts by mass. If the content of the dichroic dye is within this range, it can be polymerized without disturbing the orientation of the polymerizable liquid crystal compound (B).
If the content of the dichroic dye is too high, the orientation of the polymerizable liquid crystal compound (B) may be inhibited.

The polymerizable liquid crystal composition B constituting the polarizing film can contain one or more leveling agents. The leveling agent has the function of adjusting the fluidity of the polymerizable liquid crystal composition B and making the coating film obtained by coating the polymerizable liquid crystal composition B more flat. agents. The leveling agent is preferably at least one selected from the group consisting of a leveling agent containing a polyacrylate compound as a main component and a leveling agent containing a fluorine atom-containing compound as a main component.

Examples of leveling agents mainly composed of polyacrylate compounds include "BYK-350", "BYK-352", "BYK-353", "BYK-354", "BYK-355", "BYK-358N", BYK-361N", "BYK-380", "BYK-381" and "BYK-392" [BYK Chemie].

Examples of leveling agents mainly composed of fluorine atom-containing compounds include "Megafac (registered trademark) R-08", "R-30", "R-90", "F-410", and "F -411", "F-443", "F-445", "F-470", "F-471", "F-477", "F-479", "F- 482" and "F-483" [DIC Corporation]; "Surflon (registered trademark) S-381", "S-382", "S-383", "S-393", SC-101", "SC-105", "KH-40" and "SA-100" [AGC Seimi Chemical Co., Ltd.]; "E1830", "E5844" [Daikin Fine Chemicals Laboratory]; F-top EF301", "F-top EF303", "F-top EF351" and "F-top EF352" [Mitsubishi Materials Electronics Chemical Co., Ltd.]. A leveling agent can be used individually or in combination of 2 or more types.

When the polymerizable liquid crystal composition B constituting the polarizing film contains a leveling agent, the content thereof is preferably 0.05 to 5 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound (B). 05 to 3 parts by mass is more preferable. When the content of the leveling agent is within the above range, it is easy to horizontally align the polymerizable liquid crystal compound (B), and the obtained polarizing film tends to be smoother. When the content of the leveling agent with respect to the polymerizable liquid crystal compound (B) is within the above range, the polarizing film obtained tends to be less uneven.

The polymerizable liquid crystal composition B constituting the polarizing film preferably contains one or more polymerization initiators. The polymerization initiator is a compound capable of initiating the polymerization reaction of the polymerizable liquid crystal compound (B), and is preferably a photopolymerization initiator because it can initiate the polymerization reaction under lower temperature conditions. Specifically, photopolymerization initiators capable of generating active radicals or acids by the action of light may be mentioned, and among these, photopolymerization initiators capable of generating radicals by the action of light are preferred.

Polymerization initiators include benzoin compounds, benzophenone compounds, alkylphenone compounds, acylphosphine oxide compounds, triazine compounds, iodonium salts and sulfonium salts.

Benzoin compounds include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether.

Benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyldiphenylsulfide, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone. and 2,4,6-trimethylbenzophenone.

Alkylphenone compounds include diethoxyacetophenone, 2-methyl-2-morpholino-1-(4-methylthiophenyl)propan-1-one, 2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butane -1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1,2-diphenyl-2,2-dimethoxyethan-1-one, 2-hydroxy-2-methyl-1-[ 4-(2-hydroxyethoxy)phenyl]propan-1-one, 1-hydroxycyclohexylphenyl ketone and 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propan-1-one oligomers.

Acylphosphine oxide compounds include 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

Triazine compounds include 2,4-bis(trichloromethyl)-6-(4-methoxyphenyl)-1,3,5-triazine and 2,4-bis(trichloromethyl)-6-(4-methoxynaphthyl) -1,3,5-triazine, 2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-triazine, 2,4-bis(trichloromethyl)-6- [2-(5-methylfuran-2-yl)ethenyl]-1,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(furan-2-yl)ethenyl]-1 ,3,5-triazine, 2,4-bis(trichloromethyl)-6-[2-(4-diethylamino-2-methylphenyl)ethenyl]-1,3,5-triazine and 2,4-bis(trichloro methyl)-6-[2-(3,4-dimethoxyphenyl)ethenyl]-1,3,5-triazine.

A commercially available one can be used as the polymerization initiator. Commercially available polymerization initiators include "Irgacure (registered trademark) 907", "Irgacure (registered trademark) 184", "Irgacure (registered trademark) 651", "Irgacure (registered trademark) 819", and "Irgacure (registered trademark) 819". Registered trademark) 250”, “Irgacure (registered trademark) 369” (Ciba Japan Co., Ltd.); Seiko Chemical Co., Ltd.); "Kayacure (registered trademark) BP100" (Nippon Kayaku Co., Ltd.); "Kayacure (registered trademark) UVI-6992" (manufactured by Dow); ", "Adeka Optomer SP-170" (ADEKA Corporation); "TAZ-A", "TAZ-PP" (Nippon SiberHegner); and "TAZ-104" (Sanwa Chemical Co.).

When the polymerizable liquid crystal composition B constituting the polarizing film contains a polymerization initiator, the content thereof is appropriately adjusted according to the type and amount of the polymerizable liquid crystal compound contained in the polymerizable liquid crystal composition B. However, it is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 0.5 to 8 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound. If the content of the polymerizable initiator is within this range, polymerization can be carried out without disturbing the orientation of the polymerizable liquid crystal compound (B).

When the polymerizable liquid crystal composition B constituting the polarizing film contains a photopolymerization initiator, the polymerizable liquid crystal composition B may further contain a photosensitizer. Photosensitizers include xanthone compounds such as xanthone and thioxanthone (e.g., 2,4-diethylthioxanthone, 2-isopropylthioxanthone, etc.); anthracene compounds, such as anthracene and alkoxy group-containing anthracene (e.g., dibutoxyanthracene); Phenothiazines and rubrenes are included. A photosensitizer can be used individually or in combination of 2 or more types.

When the polymerizable liquid crystal composition B constituting the polarizing film contains a photopolymerization initiator and a photosensitizer, the polymerization reaction of the polymerizable liquid phase compound (B) contained in the polymerizable liquid crystal composition B is further accelerated. can be promoted. The amount of the photosensitizer used can be appropriately adjusted according to the type and amount of the photopolymerization initiator and the polymerizable liquid crystal compound. It is preferably 0.5 to 10 parts by mass, even more preferably 0.5 to 8 parts by mass.

In order to allow the polymerization reaction of the polymerizable liquid phase compound (B) to proceed more stably, the polymerizable liquid crystal composition B may contain an appropriate amount of a polymerization inhibitor, whereby the polymerizable liquid crystal compound (B ), the degree of progress of the polymerization reaction can be easily controlled.

Polymerization inhibitors include hydroquinone, alkoxy group-containing hydroquinone, alkoxy group-containing catechol (e.g., butyl catechol), pyrogallol, and radical scavengers such as 2,2,6,6-tetramethyl-1-piperidinyloxy radicals. thiophenols; β-naphthylamines and β-naphthols.

When the polymerizable liquid crystal composition B constituting the polarizing film contains a polymerization inhibitor, the content thereof can be appropriately adjusted according to the type and amount of the polymerizable liquid crystal compound, the amount of the photosensitizer used, and the like. However, it is preferably 0.1 to 30 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 0.5 to 8 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal compound B. If the content of the polymerization inhibitor is within this range, polymerization can be carried out without disturbing the orientation of the polymerizable liquid crystal.

The polymerizable liquid phase composition B constituting the polarizing film may contain additives other than leveling agents, polymerization initiators, photosensitizers, and polymerization inhibitors. Other additives include, for example, antioxidants, release agents, stabilizers, colorants such as bluing agents, flame retardants, and lubricants. When the polymerizable liquid crystal composition contains other additives, the content of the other additives is more than 0% and 20% by mass or less with respect to the mass of the solid content of the polymerizable liquid crystal composition. is preferable, more preferably more than 0% and 10% by mass or less.

The polarizing film is usually prepared by adding a solvent to the polymerizable liquid crystal composition B containing the polymerizable liquid crystal compound (B) and the dichroic dye, and optionally the above additives, and mixing and stirring. The composition for forming a polarizing film is applied onto a substrate, an alignment film described later, an optically anisotropic film, a second optically anisotropic film, etc., and the polymerizable liquid phase compound (B ) is polymerized.

A solvent can be appropriately selected according to the solubility of the polymerizable liquid crystal compound (B) and the dichroic dye. Since smectic liquid crystal compounds generally have high viscosity, adding a solvent to the polymerizable liquid crystal composition B facilitates coating, and as a result, often facilitates the formation of a polarizing film. Specific examples of solvents include alcohol solvents such as water, methanol, ethanol, ethylene glycol, isopropyl alcohol, propylene glycol, methyl cellosolve, butyl cellosolve, propylene glycol monomethyl ether, ethyl acetate, butyl acetate, ethylene glycol methyl ether acetate, γ- ester solvents such as butyrolactone, propylene glycol methyl ether acetate and ethyl lactate; ketone solvents such as acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, methyl amyl ketone and methyl isobutyl ketone; aliphatic hydrocarbon solvents such as pentane, hexane and heptane; Examples include aromatic hydrocarbon solvents such as toluene and xylene, nitrile solvents such as acetonitrile, ether solvents such as tetrahydrofuran and dimethoxyethane, and chlorinated hydrocarbon solvents such as chloroform and chlorobenzene. These solvents can be used alone or in combination of two or more. The content of the solvent is preferably 50 to 500 parts by mass, more preferably 150 to 300 parts by mass with respect to 100 parts by mass of the polymerizable liquid crystal composition B.

The substrate is typically a transparent substrate. In the polarizing plate of the present invention, when the substrate is not installed on the display surface of the display element, for example, when the laminate obtained by removing the substrate from the polarizing plate of the present invention is installed on the display surface of the display element, the substrate does not have to be transparent. A transparent base material means a base material having transparency capable of transmitting light, particularly visible light, and transparency means a characteristic of having a transmittance of 80% or more for light rays having a wavelength of 380 to 780 nm. say. A translucent resin base material is mentioned as a specific transparent base material. Examples of the resin constituting the translucent resin base material include polyolefins such as polyethylene and polypropylene; cyclic olefin resins such as norbornene-based polymers; polyvinyl alcohol; polyethylene terephthalate; Cellulose esters such as diacetyl cellulose, cellulose acetate propionate; polyethylene naphthalate; polycarbonates; polysulfones; polyethersulfones; polyetherketones; Polyethylene terephthalate, polymethacrylic acid ester, cellulose ester, cyclic olefin resin, or polycarbonate are preferred from the viewpoint of availability and transparency. Cellulose ester is obtained by esterifying some or all of the hydroxyl groups contained in cellulose, and can be easily obtained from the market. Cellulose ester base materials are also readily available on the market. Commercially available cellulose ester substrates include, for example, "Fujitac Film" (Fuji Photo Film Co., Ltd.); "KC8UX2M", "KC8UY" and "KC4UY" (Konica Minolta Opto Co., Ltd.).

The properties required for the base material vary depending on the structure of the polarizing plate, but usually a base material with as little retardation as possible is preferred. Substrates having as little retardation as possible include cellulose ester films having no retardation, such as Zero Tack (Konica Minolta Opto Co., Ltd.) and Z Tack (Fuji Film Co., Ltd.). An unstretched cyclic olefin resin substrate is also preferred.

In the case of a polarizing plate in which a polarizing film is laminated on a base material with or without an alignment film, the surface of the base material on which the polarizing film is not laminated is subjected to hard coat treatment, antireflection treatment, antistatic treatment, etc. may be made. In addition, the hard coat layer may contain additives such as ultraviolet absorbers as long as the performance is not affected.

If the thickness of the substrate is too thin, the strength tends to be low and the workability tends to be poor.

A dry film is formed by applying the polymerizable liquid crystal composition B mixed with a solvent and removing the solvent by drying under conditions in which the polymerizable liquid crystal compound (B) contained in the resulting coating film is not polymerized. be. Drying methods include a natural drying method, a ventilation drying method, a heating drying method, and a reduced pressure drying method. When the polymerizable liquid crystal compound (B) is a polymerizable smectic liquid crystal compound, it is preferable to change the liquid crystal state of the polymerizable smectic liquid crystal compound contained in the dry film to a nematic phase (nematic liquid crystal state) and then transition to the smectic phase. . In order to form a smectic phase via a nematic phase, for example, the dry film is heated to a temperature higher than the temperature at which the polymerizable smectic liquid crystal compound contained in the dry film transitions to the liquid crystal state of the nematic phase, and then the polymerizable smectic phase is formed. A method is adopted in which the liquid crystal compound is cooled to a temperature at which it exhibits a smectic phase liquid crystal state.

Next, a method of photopolymerizing the polymerizable liquid crystal compound (B) while maintaining the liquid crystal state of the smectic phase after changing the liquid crystal state of the polymerizable liquid crystal compound (B) in the dry film to the smectic phase will be described. In photopolymerization, the light irradiated to the dry film includes the type of photopolymerization initiator contained in the dry film, the type of the polymerizable liquid crystal compound (B) (in particular, the photopolymerization of the polymerizable liquid crystal compound (B) type of group) and its amount, and specific examples thereof include one selected from the group consisting of visible light, ultraviolet light, infrared light, X-rays, α-rays, β-rays and γ-rays. The above light and active electron beams can be mentioned. Among them, ultraviolet light is preferable in that it is easy to control the progress of the polymerization reaction and that a widely used photopolymerization apparatus in the field can be used. It is preferable to select the types of the polymerizable liquid crystal compound (B) and the photopolymerization initiator contained in the polymerizable liquid crystal composition B in advance. The polymerization temperature can also be controlled by irradiating light while cooling the dry film with an appropriate cooling means during polymerization. By adopting such a cooling means and polymerizing the polymerizable liquid crystal compound (B) at a lower temperature, a polarizing film can be properly formed even if a substrate having relatively low heat resistance is used. A patterned polarizing film can also be obtained by performing masking or development during photopolymerization.

Examples of the light source of the active energy ray include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, halogen lamps, carbon arc lamps, tungsten lamps, gallium lamps, excimer lasers, and wavelength ranges. LED light sources, chemical lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, etc., which emit light in the range of 380 to 440 nm can be used.

The UV irradiation intensity is usually 10 to 3,000 mW/cm ² . The ultraviolet irradiation intensity is preferably in the wavelength range effective for activation of the photopolymerization initiator. The light irradiation time is usually 0.1 seconds to 10 minutes, preferably 0.1 seconds to 5 minutes, more preferably 0.1 seconds to 3 minutes, still more preferably 0.1 seconds to 1 minute. be. When irradiated once or multiple times with such an irradiation intensity of ultraviolet rays, the cumulative amount of light is 10 to 3,000 mJ/cm ² , preferably 50 to 2,000 mJ/cm ² , more preferably 100 to 1,000 mJ/cm. ² .

By performing photopolymerization, the polymerizable liquid crystal compound (B) polymerizes while maintaining the liquid crystal state of a smectic phase, preferably a higher order smectic phase, to form a polarizing film. The polarizing film obtained by polymerizing the polymerizable liquid crystal compound (B) while maintaining the liquid crystal state of the smectic phase is different from the conventional host-guest type polarizing film, that is, the nematic phase, due to the action of the dichroic dye. It has the advantage of high polarizing performance compared to polarizing films in a liquid crystal state. Furthermore, it has the advantage of being superior in strength as compared with the one coated only with a dichroic dye or a lyotropic liquid crystal.

The thickness of the polarizing film can be appropriately selected according to the display device to which it is applied, and is preferably 0.5 to 10 μm, more preferably 1 to 5 μm, still more preferably 1 to 3 μm.

[Alignment film]
A polarizing film is preferably formed on an alignment film. The alignment film has an alignment regulating force that aligns the polymerizable liquid crystal compound in a desired direction. The alignment film has a solvent resistance that does not dissolve when a composition containing a polymerizable liquid crystal compound is applied, etc., and also has heat resistance in heat treatment for removing the solvent and for aligning the polymerizable liquid crystal compound. preferable. Examples of such an alignment film include an alignment film containing an alignment polymer, a photo-alignment film, and a groove alignment film having an uneven pattern or a plurality of grooves on the surface.

Examples of the oriented polymer include polyamides and gelatins having amide bonds in the molecule, polyimides having imide bonds in the molecule and their hydrolysates such as polyamic acid, polyvinyl alcohol, alkyl-modified polyvinyl alcohol, polyacrylamide, polyoxazole, Polyethylenimine, polystyrene, polyvinylpyrrolidone, polyacrylic acid and polyacrylic acid esters can be mentioned. Among them, polyvinyl alcohol is preferred. Orientation polymer can be used individually or in combination of 2 or more types.

An alignment film containing an alignment polymer is usually prepared by applying a composition in which an alignment polymer is dissolved in a solvent (hereinafter sometimes referred to as an alignment polymer composition) to a substrate, removing the solvent, or removing the alignment film. It is obtained by applying the polymer composition to a substrate, removing the solvent, and rubbing (rubbing method). Examples of the solvent include the same solvents as those described in the section [Polarizing film].

The concentration of the oriented polymer in the oriented polymer composition may be within a range in which the oriented polymer material can be completely dissolved in the solvent. 0.1 to 10% is more preferable.

A commercially available alignment film material may be used as it is as the alignment polymer composition. Commercially available alignment film materials include Sanever (registered trademark, manufactured by Nissan Chemical Industries, Ltd.) and Optomer (registered trademark, manufactured by JSR Corporation).

Examples of methods for applying the oriented polymer composition to a substrate include coating methods such as spin coating, extrusion, gravure coating, die coating, bar coating, and applicator methods, and printing methods such as flexography. A known method of

Examples of methods for removing the solvent contained in the oriented polymer composition include natural drying, ventilation drying, heat drying, and vacuum drying.

In order to impart an alignment regulating force to the alignment film, a rubbing treatment can be performed as necessary (rubbing method).

As a method for imparting an alignment regulating force by a rubbing method, a rubbing cloth is wound around a rotating rubbing roll, and an orienting polymer composition is applied to the substrate and then annealed to form an orientation polymer composition on the substrate surface. A method of contacting films of oriented polymers is included.

A photo-alignment film is usually formed by coating a substrate with a composition containing a polymer or monomer having a photoreactive group and a solvent (hereinafter sometimes referred to as a "composition for forming a photo-alignment film"), and applying polarized light ( Preferably, it is obtained by irradiating with polarized UV). The photo-alignment film is more preferable in that the direction of the alignment regulating force can be arbitrarily controlled by selecting the polarization direction of the irradiated polarized light.

A photoreactive group refers to a group that exhibits liquid crystal alignment ability upon irradiation with light. Specific examples thereof include groups involved in photoreactions, such as orientation induction of molecules caused by light irradiation or isomerization reactions, dimerization reactions, photocrosslinking reactions, photodecomposition reactions, and the like, which are the origin of liquid crystal alignment ability. Among them, a group involved in a dimerization reaction or a photocrosslinking reaction is preferable from the viewpoint of excellent orientation. As the photoreactive group, a group having an unsaturated bond, particularly a double bond is preferable, and a carbon-carbon double bond (C=C bond), a carbon-nitrogen double bond (C=N bond), a nitrogen-nitrogen double bond Groups having at least one selected from the group consisting of a heavy bond (N=N bond) and a carbon-oxygen double bond (C=O bond) are particularly preferred.

Photoreactive groups having a C═C bond include vinyl groups, polyene groups, stilbene groups, stilbazole groups, stilbazolium groups, chalcone groups and cinnamoyl groups. Photoreactive groups having a C═N bond include groups having structures such as aromatic Schiff bases and aromatic hydrazones. Photoreactive groups having an N=N bond include azobenzene groups, azonaphthalene groups, aromatic heterocyclic azo groups, bisazo groups, formazan groups, and groups having an azoxybenzene structure. Photoreactive groups having a C=O bond include benzophenone groups, coumarin groups, anthraquinone groups and maleimide groups. These groups may have substituents such as alkyl groups, alkoxy groups, aryl groups, allyloxy groups, cyano groups, alkoxycarbonyl groups, hydroxyl groups, sulfonic acid groups, and halogenated alkyl groups.

Among them, a photoreactive group that participates in a photodimerization reaction is preferable, the amount of polarized light irradiation required for photoalignment is relatively small, and a photoalignment film having excellent thermal stability and stability over time can be easily obtained. Cinnamoyl and chalcone groups are preferred. As the polymer having a photoreactive group, a polymer having a cinnamoyl group having a cinnamic acid structure at the end of the polymer side chain is particularly preferred.

A photo-alignment inducing layer can be formed on a substrate by applying the composition for forming a photo-alignment film onto the substrate. The solvent contained in the composition includes the same solvents as those described in the section [Polarizing film], and can be appropriately selected according to the solubility of the polymer or monomer having a photoreactive group.

The content of the polymer or monomer having a photoreactive group in the composition for forming a photo-alignment film can be appropriately adjusted depending on the type of polymer or monomer and the thickness of the desired photo-alignment film. It is preferably at least 0.2% by mass, more preferably in the range of 0.3 to 10% by mass. The composition for forming a photo-alignment film may contain a polymeric material such as polyvinyl alcohol or polyimide, or a photosensitizer, as long as the properties of the photo-alignment film are not significantly impaired.

Examples of the method of applying the composition for forming a photo-alignment film to the substrate include the same methods as the method of applying the alignment composition to the substrate. Examples of methods for removing the solvent from the coated composition for forming a photo-alignment film include natural drying, ventilation drying, heat drying, and reduced pressure drying.

In order to irradiate polarized light, the composition for forming a photo-alignment film coated on the substrate, from which the solvent has been removed, is directly irradiated with polarized UV light. A format in which the light is irradiated may also be used. Moreover, it is particularly preferable that the polarized light is substantially parallel light. The wavelength of the polarized light to be irradiated is preferably in a wavelength range in which the photoreactive group of the polymer or monomer having a photoreactive group can absorb the light energy. Specifically, UV (ultraviolet rays) with a wavelength in the range of 250 to 400 nm is particularly preferred. Examples of the light source used for the polarized irradiation include a xenon lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, and an ultraviolet light laser such as KrF and ArF. Lamps are more preferred. Among these, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, and a metal halide lamp are preferable because of their high emission intensity of ultraviolet rays having a wavelength of 313 nm. Polarized UV can be emitted by passing the light from the light source through a suitable polarizer. As such a polarizer, a polarizing filter, a polarizing prism such as Glan-Thompson or Glan-Taylor, or a wire grid type polarizer can be used.

A plurality of regions (patterns) having different liquid crystal orientation directions can be formed by masking during rubbing or polarized light irradiation.

A groove alignment film is a film having an uneven pattern or a plurality of grooves on its surface. When a polymerizable liquid crystal compound is applied to a film having a plurality of linear grooves arranged at regular intervals, liquid crystal molecules are aligned along the grooves.

As a method for obtaining a grooved alignment film, after exposure through an exposure mask having pattern-shaped slits on the surface of a photosensitive polyimide film, development and rinsing are performed to form an uneven pattern, and a plate having grooves on the surface. A method of forming a UV curable resin layer before curing on a shaped master, transferring the formed resin layer to a substrate and then curing, and a UV curable resin film before curing formed on the substrate, A method of pressing a roll-shaped master plate having a plurality of grooves to form unevenness and then curing the same may be used.

The thickness of the alignment film (orientation film containing an alignment polymer or photo-alignment film) is usually in the range of 10 to 10000 nm, preferably in the range of 10 to 1000 nm, more preferably 500 nm or less, and still more preferably It ranges from 10 to 200 nm, particularly preferably from 50 to 150 nm.

In the polarizing plate of the present invention, the slow axis of the optically anisotropic film and the absorption axis of the polarizing film are neither parallel nor orthogonal to each other. The angle θ1 between the slow axis of the optically anisotropic film and the absorption axis of the polarizing film is expressed by the following formula (2) from the viewpoint of visibility.
30°≤θ1≤60° (2)
is preferably satisfied. More preferably, the formula (2) satisfies 40°≦θ1≦50°. In particular, θ1 is preferably substantially 45°.

The polarizing plate of the present invention preferably further comprises a second optically anisotropic film. More preferably, the anisotropic films are laminated in this order.

[Second optically anisotropic film]
The second optically anisotropic film is a film having three-dimensional refractive index anisotropy. The second optically anisotropic film may be a film obtained by stretching or shrinking a polymer film. ) is preferably an oriented polymer. The second optically anisotropic film can be obtained by polymerizing a polymerizable liquid crystal composition containing an aligned polymerizable liquid crystal compound (hereinafter sometimes referred to as polymerizable liquid crystal composition A).

The three-dimensional refractive index ellipsoid formed by the second optically anisotropic film may have biaxiality, but preferably has uniaxiality. The second optically anisotropic film is a film made of a polymer (horizontal alignment layer) of a polymerizable liquid phase composition containing a polymerizable liquid crystal compound aligned horizontally with respect to the plane of the film. Alternatively, it may be a film made of a polymer (vertical alignment layer) of a polymerizable liquid phase composition containing a polymerizable liquid crystal compound oriented in a direction perpendicular to the plane of the film, or a hybrid alignment. It may be a oriented film (hybrid orientation layer) or an obliquely oriented film (oblique orientation layer).

The second optically anisotropic film in the present invention is represented by the following formulas (3), (4) and (5)
100 nm≦Re(550)≦160 nm (3)
Re(450)/Re(550)≤1.0 (4)
1.00≦Re(650)/Re(550) (5)
[Wherein, Re (450), Re (550) and Re (650) represent in-plane retardation at wavelengths of 450 nm, 550 nm and 650 nm, respectively]
is preferably satisfied.

When the in-plane retardation ReQ(550) of the second optically anisotropic film is within the range of formula (3), the hue change such as the hue of the display front including the polarizing plate becomes red or blue. can be suppressed. A more preferable range of the in-plane retardation value is 130 nm≦Re1(550)≦150 nm. When ReQ(450)/ReQ(550) of the second optically anisotropic film is 1.00 or less and ReQ(650)/ReQ(550) is 1.00 or more, the second optical anisotropic film A polarizing plate (elliptically polarizing plate) provided with an anisotropic film can be prevented from deteriorating in ellipticity, and the function as an elliptically polarizing plate when viewed from the front is improved. This "ReQ(450)/ReQ(550)" is preferably 0.75 to 0.92, more preferably 0.77 to 0.87, still more preferably 0.79 to 0.85.

The polymerizable liquid crystal compound (A) means a liquid crystal compound having a polymerizable functional group, especially a photopolymerizable functional group. A photopolymerizable functional group is a group that can participate in a polymerization reaction by an active radical generated from a photopolymerization initiator, an acid, or the like. Photopolymerizable functional groups include vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group, oxiranyl group and oxetanyl group.
Among them, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group and an oxetanyl group are preferred, and an acryloyloxy group is more preferred. Liquid crystallinity may be thermotropic liquid crystal or lyotropic liquid crystal, and phase order structure may be nematic liquid crystal or smectic liquid crystal. As the polymerizable liquid crystal compound, only one type may be used, or two or more types may be used in combination.

As the polymerizable liquid phase compound (A), all of the following (6) to (9) are used from the viewpoint of facilitating film formation and imparting retardation properties represented by the formulas (4) and (5). A compound that satisfies the

(6) a compound capable of forming a nematic phase;
(7) The polymerizable liquid crystal compound has π electrons along the major axis direction (a).
(8) It has π electrons in a direction [intersecting direction (b)] that intersects the major axis direction (a).
(9) A polymerizable liquid crystal compound defined by the following formula (i), where N(πa) is the total number of π electrons present in the longitudinal direction (a), and N(Aa) is the total molecular weight present in the longitudinal direction. π electron density in the long axis direction (a) of
D(πa)=N(πa)/N(Aa) (i)
and a polymerizable liquid crystal compound defined by the following formula (ii), where N(πb) is the sum of π electrons present in the cross direction (b), and N(Ab) is the sum of the molecular weights present in the cross direction (b). π electron density in the cross direction (b) of
D(πb)=N(πb)/N(Ab) (ii)
and
0≦[D(πa)/D(πb)]≦1
[that is, the π electron density in the cross direction (b) is higher than the π electron density in the long axis direction (a)].
Incidentally, a polymerizable liquid crystal compound satisfying all of the above (6) to (9) can be applied onto an alignment film formed by rubbing treatment and heated to a phase transition temperature or higher to form a nematic phase. be. In the nematic phase formed by aligning the polymerizable liquid crystal compounds, the long axis directions of the polymerizable liquid crystal compounds are usually oriented parallel to each other, and this long axis direction is the alignment direction of the nematic phase.

で表される化合物が挙げられる。前記式（II）で表される化合物は単独又は二種以上組み合わせて使用できる。Polymerizable liquid crystal compounds having the above properties generally exhibit reverse wavelength dispersion in many cases. Specific examples of the compound satisfying the above properties (6) to (9) include the following formula (II):

The compound represented by is mentioned. The compounds represented by formula (II) can be used singly or in combination of two or more.

In formula (II), Ar represents a divalent aromatic group which may have a substituent. The aromatic group referred to herein is a group having a planar cyclic structure, and the number of π electrons of the cyclic structure is [4n+2] according to Hückel's rule. Here, n represents an integer. In the case where a ring structure is formed by including heteroatoms such as -N= and -S-, the non-covalently bonded electron pairs on these heteroatoms satisfy Hückel's rule and have aromaticity. At least one or more of a nitrogen atom, an oxygen atom and a sulfur atom are preferably contained in the divalent aromatic group.

G ¹ and G ² each independently represent a divalent aromatic group or a divalent alicyclic hydrocarbon group.
Here, the hydrogen atom contained in the divalent aromatic group or divalent alicyclic hydrocarbon group is a halogen atom, an alkyl group having 1 to 4 carbon atoms, a fluoroalkyl group having 1 to 4 carbon atoms, a carbon may be substituted with an alkoxy group, cyano group or nitro group having a number of 1 to 4, and the carbon atoms constituting the divalent aromatic group or divalent alicyclic hydrocarbon group are oxygen atoms, sulfur atoms Alternatively, it may be substituted with a nitrogen atom.

L ¹ , L ² _, B ¹ and B ² are each independently a single bond or a divalent linking group.

k and l each independently represents an integer of 0 to 3 and satisfies the relationship 1≦k+l. Here, when 2≦k+l, B ¹ and B ² and G ¹ and G ² may be the same or different from each other.

E ¹ and E ² each independently represent an alkanediyl group having 1 to 17 carbon atoms, wherein a hydrogen atom contained in the alkanediyl group may be substituted with a halogen atom; —CH ₂ — included may be substituted with —O—, —S—, or —Si—. P ¹ and P ² each independently represent a polymerizable group or a hydrogen atom, at least one of which is a polymerizable group.

G ¹ and G ² are each independently preferably a 1,4-phenylenediyl group optionally substituted with at least one substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms. , a 1,4-cyclohexanediyl group optionally substituted with at least one substituent selected from the group consisting of a halogen atom and an alkyl group having 1 to 4 carbon atoms, more preferably 1 substituted with a methyl group ,4-phenylenediyl group, unsubstituted 1,4-phenylenediyl group, or unsubstituted 1,4-trans-cyclohexanediyl group, particularly preferably unsubstituted 1,4-phenylenediyl group, or unsubstituted It is a substituted 1,4-trans-cyclohexanediyl group. At least one of G ¹ and G ² present in plurality is preferably a divalent alicyclic hydrocarbon group, and at least one of G ¹ and G ² bonded to L ¹ or L ² is more preferably a divalent alicyclic hydrocarbon group.

L ¹ and L ² are each independently preferably a single bond, an alkylene group having 1 to 4 carbon atoms, —O—, —S—, —R ^a1 OR ^a2 —, —R ^a3 COOR ^a4 —, —R ^a5 OCOR ^a6 -, R ^a7 OC=OOR ^a8 -, -N=N-, -CR ^c =CR ^d -, or C≡C-. Here, R ^a1 to R ^a8 each independently represent a single bond or an alkylene group having 1 to 4 carbon atoms, and R ^c and R ^d represent an alkyl group having 1 to 4 carbon atoms or a hydrogen atom. L ¹ and L ² are each independently more preferably a single bond, -OR ^a2-1 -, -CH ₂ -, -CH ₂ CH ₂ -, -COOR ^a4-1 -, or OCOR ^a6-1 - . Here, R ^a2-1 , R ^a4-1 and R ^a6-1 each independently represent a single bond, —CH ₂ — or —CH ₂ CH ₂ —. L ¹ and L ² are each independently more preferably a single bond, -O-, -CH ₂ CH ₂ -, -COO-, -COOCH ₂ CH ₂ -, or OCO-.

In one preferred embodiment of the present invention, at least one of G ¹ and G ² in formula (II) is a divalent alicyclic hydrocarbon group, and the divalent alicyclic hydrocarbon group is , a polymerizable liquid crystal compound in which an optionally substituted divalent aromatic group Ar and L ¹ and/or L ² of —COO— are bonded.

B ¹ and B ² are each independently preferably a single bond, an alkylene group having 1 to 4 carbon atoms, —O—, —S—, —R ^a9 OR ^a10 —, —R ^a11 COOR ^a12 —, —R ^a13 OCOR ^a14 -, or R ^a15 OC=OOR ^a16 -. Here, R ^a9 to R ^a16 each independently represent a single bond or an alkylene group having 1 to 4 carbon atoms. B ¹ and B ² are each independently more preferably a single bond, -OR ^a10-1 -, -CH ₂ -, -CH ₂ CH ₂ -, -COOR ^a12-1 -, or OCOR ^a14-1 - . Here, R ^a10-1 , R ^a12-1 and R ^a14-1 each independently represent a single bond, —CH ₂ — or —CH ₂ CH ₂ —. B ¹ and B ² are each independently more preferably a single bond, -O-, -CH ₂ CH ₂ -, -COO-, -COOCH ₂ CH ₂ -, -OCO-, or OCOCH ₂ CH ₂ - .

k and l are preferably in the range of 2≦k+l≦6, preferably k+l=4, and more preferably k=2 and l=2 from the viewpoint of exhibiting reverse wavelength dispersion. It is more preferable that k=2 and l=2 because the structure is symmetrical.

E ¹ and E ² are each independently preferably an alkanediyl group having 1 to 17 carbon atoms, more preferably an alkanediyl group having 4 to 12 carbon atoms.

Examples of polymerizable groups represented by P ¹ or P ² include epoxy group, vinyl group, vinyloxy group, 1-chlorovinyl group, isopropenyl group, 4-vinylphenyl group, acryloyloxy group, methacryloyloxy group and oxiranyl. group, and oxetanyl group. Among these, an acryloyloxy group, a methacryloyloxy group, a vinyloxy group, an oxiranyl group and an oxetanyl group are preferred, and an acryloyloxy group is more preferred.

Ar preferably has at least one selected from an optionally substituted aromatic hydrocarbon ring, an optionally substituted aromatic heterocycle, and an electron-withdrawing group. Examples of the aromatic hydrocarbon ring include benzene ring, naphthalene ring, anthracene ring and the like, with benzene ring and naphthalene ring being preferred. Examples of the aromatic heterocyclic ring include furan ring, benzofuran ring, pyrrole ring, indole ring, thiophene ring, benzothiophene ring, pyridine ring, pyrazine ring, pyrimidine ring, triazole ring, triazine ring, pyrroline ring, imidazole ring, and pyrazole ring. , thiazole ring, benzothiazole ring, thienothiazole ring, oxazole ring, benzoxazole ring, and phenanthroline ring. Among these, it is preferable to have a thiazole ring, a benzothiazole ring, or a benzofuran ring, and it is more preferable to have a benzothiazole group. Moreover, when a nitrogen atom is contained in Ar, the nitrogen atom preferably has a π electron.

In formula (II), the total number _Nπ of π electrons contained in the divalent aromatic group represented by Ar is preferably 8 or more, more preferably 10 or more, still more preferably 14 or more, and particularly It is preferably 16 or more. Also, it is preferably 30 or less, more preferably 26 or less, and still more preferably 24 or less.

Examples of aromatic groups represented by Ar include the following groups.

In formulas (Ar-1) to (Ar-22), the * mark represents a connecting portion, and Z ⁰ , Z ¹ and Z ² each independently represent a hydrogen atom, a halogen atom, or an alkyl having 1 to 12 carbon atoms. a cyano group, a nitro group, an alkylsulfinyl group having 1 to 12 carbon atoms, an alkylsulfonyl group having 1 to 12 carbon atoms, a carboxyl group, a fluoroalkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an alkylthio group having 1 to 12 carbon atoms, an N-alkylamino group having 1 to 12 carbon atoms, an N,N-dialkylamino group having 2 to 12 carbon atoms, an N-alkylsulfamoyl group having 1 to 12 carbon atoms, or carbon represents an N,N-dialkylsulfamoyl group of numbers 2 to 12;

Q ¹ and Q ² each independently represent -CR ^2' R ^3' -, -S-, -NH-, -NR ^2' -, -CO- or O-, and R ^2' and R ^3' each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

^J1 and ^J2 each independently represent a carbon atom or a nitrogen atom.

Y ¹ , Y ² and Y ³ each independently represent an optionally substituted aromatic hydrocarbon group or aromatic heterocyclic group.

W ¹ and W ² each independently represent a hydrogen atom, a cyano group, a methyl group or a halogen atom, and m represents an integer of 0-6.

Examples of the aromatic hydrocarbon group for Y ¹ , Y ² and Y ³ include aromatic hydrocarbon groups having 6 to 20 carbon atoms such as phenyl group, naphthyl group, anthryl group, phenanthryl group and biphenyl group. , is preferably a naphthyl group, more preferably a phenyl group. The aromatic heterocyclic group includes a C4-20 group containing at least one heteroatom such as a nitrogen atom, an oxygen atom, a sulfur atom such as a furyl group, a pyrrolyl group, a thienyl group, a pyridinyl group, a thiazolyl group and a benzothiazolyl group. An aromatic heterocyclic group can be mentioned, and a furyl group, a thienyl group, a pyridinyl group, a thiazolyl group, and a benzothiazolyl group are preferable.

Y ¹ and Y ² may each independently be an optionally substituted polycyclic aromatic hydrocarbon group or polycyclic aromatic heterocyclic group. A polycyclic aromatic hydrocarbon group refers to a condensed polycyclic aromatic hydrocarbon group or a group derived from an aromatic ring assembly. A polycyclic aromatic heterocyclic group refers to a condensed polycyclic aromatic heterocyclic group or a group derived from an aromatic ring assembly.

Z ⁰ , Z ¹ and Z ² are each independently preferably a hydrogen atom, a halogen atom, an alkyl group having 1 to 12 carbon atoms, a cyano group, a nitro group, an alkoxy group having 1 to 12 carbon atoms, and Z ⁰ is more preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or a cyano group, and Z ¹ and Z ² are more preferably a hydrogen atom, a fluorine atom, a chlorine atom, a methyl group, or a cyano group.

Q ¹ and Q ² are preferably -NH-, -S-, -NR ^2' - and -O-, and R ^2' is preferably a hydrogen atom. Among them, -S-, -O- and -NH- are particularly preferred.

Among formulas (Ar-1) to (Ar-22), formulas (Ar-6) and (Ar-7) are preferable from the viewpoint of molecular stability.

In formulas (Ar-16) to (Ar-22), Y ¹ may form an aromatic heterocyclic group together with the nitrogen atom to which it is attached and Z ⁰ . Examples of the aromatic heterocyclic group include those described above as the aromatic heterocyclic ring that Ar may have, and examples thereof include pyrrole ring, imidazole ring, pyrroline ring, pyridine ring, pyrazine ring, pyrimidine ring, indole ring, quinoline ring, isoquinoline ring, purine ring, pyrrolidine ring and the like. This aromatic heterocyclic group may have a substituent. In addition, Y ¹ , together with the nitrogen atom and Z ⁰ to which it is attached, may be the aforementioned optionally substituted polycyclic aromatic hydrocarbon group or polycyclic aromatic heterocyclic group. Examples include benzofuran ring, benzothiazole ring, benzoxazole ring and the like. The compound represented by formula (II) can be produced, for example, according to the method described in JP-A-2010-31223.

The polymerizable liquid crystal composition A constituting the second optically anisotropic film can contain the additives contained in the polymerizable liquid crystal composition B, which are exemplified.

The content of the polymerizable liquid crystal compound (A) in the polymerizable liquid crystal composition A constituting the second optically anisotropic film is, for example, 70 to 70 parts per 100 parts by mass of the solid content of the polymerizable liquid crystal composition A. 99.5 parts by mass, preferably 80 to 99 parts by mass, more preferably 90 to 98 parts by mass. If the content is within the above range, the orientation of the second optically anisotropic film tends to be high. Here, the solid content refers to the total amount of components of the polymerizable liquid crystal composition A excluding volatile components such as solvents.

The second optically anisotropic film is a second optical film prepared by adding a solvent to a polymerizable liquid crystal composition A containing a polymerizable liquid crystal compound (A) and, if necessary, additives, and mixing and stirring. The composition for forming an anisotropic film is coated on the substrate, the alignment film, the polarizing film, the optically anisotropic film, etc., and then the solvent is removed. It can be obtained by curing the liquid crystal compound (A) with heating and/or active energy rays. Preferably, a second optically anisotropic film is formed on the alignment film.

Examples of the coating method for the second optically anisotropic film include the same methods as those described in the section [Optically anisotropic film], and examples of the solvent include those described in the section [Polarizing film]. A similar example can be given. As the active energy ray and irradiation conditions, the same active energy ray and irradiation conditions as described in the section [Polarizing film] can be exemplified.

The thickness of the second optically anisotropic film can be appropriately selected according to the display device to which it is applied. It is more preferably 1 to 3 μm.

In the polarizing plate of the present invention, from the viewpoint of preventing reflection of external light, the angle θ2 formed by the slow axis of the second optically anisotropic film and the absorption axis of the polarizing film is expressed by the following formula (6)
30°≤θ2≤60° (6)
is preferably satisfied. More preferably, the formula (6) satisfies 40°≦θ2≦50°. In particular, θ2 is preferably substantially 45°.

Since the polarizing plate of the present invention includes the optically anisotropic film and the polarizing film, it has excellent visibility even when a display device including the polarizing plate is viewed through polarized sunglasses. For example, even when the angle of the display device is changed while wearing polarized sunglasses, disturbance of display hue is suppressed or prevented, and excellent visibility can be exhibited. Moreover, in the present invention, since the polarizing plate used for the front plate of the display device is provided with a predetermined retardation, the film can be made thinner without providing a separate retardation film. Furthermore, since the polyimide polymer is included, the bendability (or flexibility) is good, and coloration or the like during bending is suppressed.

The polarizing plate of the present invention may contain one or more of the substrate, the alignment film, the optically anisotropic film, and the second optically anisotropic film, and other layers other than these layers. may contain one or more. Other layers include, for example, an optically anisotropic film other than the optically anisotropic film and the second optically anisotropic film, a protective layer, an adhesive layer, and the like. In the polarizing plate of the present invention, the alignment film, the optically anisotropic film, the second optically anisotropic film, the protective layer, and the like may be directly formed on each layer or substrate, or may be adhesively bonded. You may bond through an adhesive layer.

The protective layer is usually made of polyfunctional acrylate (methacrylate), urethane acrylate, polyester acrylate, epoxy acrylate, acrylic oligomer or polymer, polyvinyl alcohol, ethylene-vinyl alcohol copolymer, polyvinylpyrrolidone, starches, methyl cellulose, carboxy It is preferably formed from a protective layer-forming composition containing a water-soluble polymer such as methylcellulose or sodium alginate and a solvent.

Examples of the solvent contained in the composition for forming a protective layer include the same solvents as described in the section [Polarizing film], and among them, at least one solvent selected from the group consisting of water, alcohol solvents and ether solvents. A solvent is preferable because it does not dissolve the layer forming the protective layer. Alcohol solvents include methanol, ethanol, butanol, ethylene glycol, isopropyl alcohol, propylene glycol, ethylene glycol methyl ether, ethylene glycol butyl ether and propylene glycol monomethyl ether. Ether solvents include ethylene glycol monomethyl ether acetate and propylene glycol monomethyl ether acetate. Among them, ethanol, isopropyl alcohol, propylene glycol monomethyl ether and propylene glycol monomethyl ether acetate are preferred.

The film thickness of the protective layer is 0.1 to 10 μm, preferably 0.3 to 5.0 μm.

Adhesives include pressure-sensitive adhesives, dry-hardening adhesives, and chemically reactive adhesives. Examples of chemically reactive adhesives include active energy ray-curable adhesives.

A pressure-sensitive adhesive usually contains a polymer and may contain a solvent. Polymers include acrylic polymers, silicone polymers, polyesters, polyurethanes, polyethers, and the like. Among them, acrylic pressure-sensitive adhesives containing acrylic polymers have excellent optical transparency, moderate wettability and cohesive strength, excellent adhesiveness, high weather resistance and heat resistance, and are resistant to heat. It is preferable because it is less likely to float or peel off under humidified conditions.

Examples of acrylic polymers include (meth)acrylates in which the alkyl group of the ester moiety is an alkyl group having 1 to 20 carbon atoms such as methyl, ethyl or butyl, (meth)acrylic acid and hydroxyethyl (meth)acrylate. A copolymer with a (meth)acrylic monomer having a functional group such as is preferred.

The pressure-sensitive adhesive containing such a copolymer has excellent adhesiveness, and can be removed relatively easily without causing adhesive residue on the transfer-receiving material even when it is removed after being attached to the transfer-receiving material. It is preferred because it can be removed. The glass transition temperature of the acrylic polymer is preferably 25°C or lower, more preferably 0°C or lower. The weight average molecular weight of such acrylic polymer is preferably 100,000 or more.

Examples of the solvent include the same solvents as those described in the section [Polarizing film]. The pressure-sensitive adhesive may contain a light diffusing agent. The light diffusing agent is an additive that imparts light diffusing properties to the pressure-sensitive adhesive, and may be fine particles having a refractive index different from the refractive index of the polymer contained in the pressure-sensitive adhesive. Light diffusing agents include fine particles made of inorganic compounds and fine particles made of organic compounds (polymers). Since many of the polymers contained as active ingredients in the adhesive, including acrylic polymers, have a refractive index of about 1.4 to 1.6, the light diffusing agent whose refractive index is 1.2 to 1.8 It is preferable to select them appropriately. The refractive index difference between the polymer contained as an active ingredient in the adhesive and the light diffusing agent is usually 0.01 or more, and preferably 0.01 to 0.2 from the viewpoint of the brightness and displayability of the display device. The microparticles used as the light diffusing agent are preferably spherical microparticles, more preferably microparticles close to monodispersion, and more preferably microparticles having an average particle diameter of 2 to 6 μm. The refractive index is measured by the common minimum deviation method or Abbe refractometer.

Fine particles made of inorganic compounds include aluminum oxide (refractive index: 1.76) and silicon oxide (refractive index: 1.45). Examples of fine particles made of an organic compound (polymer) include melamine beads (refractive index 1.57), polymethyl methacrylate beads (refractive index 1.49), methyl methacrylate/styrene copolymer resin beads (refractive index 1.50 ~1.59), polycarbonate beads (refractive index 1.55), polyethylene beads (refractive index 1.53), polystyrene beads (refractive index 1.6), polyvinyl chloride beads (refractive index 1.46), and silicone Resin beads (refractive index 1.46) and the like can be mentioned. The content of the light diffusing agent is usually 3 to 30 parts by mass with respect to 100 parts by mass of the polymer.

The thickness of the pressure-sensitive adhesive is determined according to its adhesive strength and the like, and is not particularly limited, but is usually 1 to 40 μm. The thickness is preferably 3 to 25 μm, more preferably 5 to 20 μm, from the viewpoint of workability, durability, and the like. By setting the thickness of the adhesive layer formed from the adhesive to 5 to 20 μm, brightness is maintained when the display device is viewed from the front or obliquely, and blurring and blurring of the displayed image are suppressed. can be made difficult.

The drying-hardening adhesive may contain a solvent. The drying-hardening adhesive contains, as a main component, a polymer of a monomer having a protic functional group such as a hydroxyl group, a carboxyl group, or an amino group and an ethylenically unsaturated group, or a urethane polymer. Examples include compositions containing cross-linking agents or curing compounds such as aldehydes, epoxy compounds, epoxy resins, melamine compounds, zirconia compounds, and zinc compounds. Polymers of monomers having a protic functional group such as a hydroxyl group, a carboxyl group, or an amino group and an ethylenically unsaturated group include ethylene-maleic acid copolymers, itaconic acid copolymers, acrylic acid copolymers, and acrylamide. Copolymers, saponified products of polyvinyl acetate, polyvinyl alcohol resins, and the like can be mentioned.

Polyvinyl alcohol resins include polyvinyl alcohol, partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, acetoacetyl group-modified polyvinyl alcohol, methylol group-modified polyvinyl alcohol, and amino group-modified polyvinyl alcohol. mentioned. The content of the polyvinyl alcohol-based resin in the water-based adhesive is usually 1 to 10 parts by mass, preferably 1 to 5 parts by mass, per 100 parts by mass of water.

Examples of urethane resins include polyester-based ionomer-type urethane resins.
The polyester-based ionomer-type urethane resin referred to here is a urethane resin having a polyester skeleton, and is a resin into which a small amount of an ionic component (hydrophilic component) has been introduced. Since the ionomer-type urethane resin is emulsified in water to form an emulsion without using an emulsifier, it can be used as a water-based pressure-sensitive adhesive. When using a polyester-based ionomer-type urethane resin, it is effective to blend a water-soluble epoxy compound as a cross-linking agent.

Examples of epoxy resins include polyamide epoxy resins obtained by reacting epichlorohydrin with polyamide polyamines obtained by reacting polyalkylenepolyamines such as diethylenetriamine or triethylenetetramine with dicarboxylic acids such as adipic acid. Commercially available polyamide epoxy resins include "Sumireze Resin (registered trademark) 650" and "Sumireze Resin 675" (manufactured by Sumika Chemtex Co., Ltd.) and "WS-525" (manufactured by Japan PMC Co., Ltd.). etc. When an epoxy resin is blended, the amount added is usually 1 to 100 parts by mass, preferably 1 to 50 parts by mass, per 100 parts by mass of the polyvinyl alcohol resin.

The thickness of the adhesive layer formed from the drying-hardening adhesive is usually 0.001 to 5 μm, preferably 0.01 to 2 μm, more preferably 0.01 to 0.5 μm. be. If the pressure-sensitive adhesive layer formed from the drying-hardening adhesive is too thick, the appearance tends to be poor.

The active energy ray-curable adhesive may contain a solvent. An active energy ray-curable adhesive is an adhesive that is cured by being irradiated with an active energy ray. The active energy ray-curable adhesive includes a cationic polymerizable adhesive containing an epoxy compound and a cationic polymerization initiator, a radically polymerizable adhesive containing an acrylic curing component and a radical polymerization initiator, and an epoxy compound. An adhesive containing both a cationic polymerizable curing component such as an acrylic compound and a radically polymerizable curing component such as an acrylic compound, and further containing a cationic polymerization initiator and a radical polymerization initiator, and these polymerization initiators Examples include an adhesive that is cured by irradiating an electron beam without being exposed.

Among them, a radically polymerizable active energy ray-curable adhesive containing an acrylic curing component and a photoradical polymerization initiator, and a cationically polymerizable active energy ray-curable adhesive containing an epoxy compound and a photocationic polymerization initiator. agents are preferred. Examples of acrylic curing components include (meth)acrylates such as methyl (meth)acrylate and hydroxyethyl (meth)acrylate, and (meth)acrylic acid. The active energy ray-curable adhesive containing an epoxy compound may further contain a compound other than the epoxy compound. Examples of compounds other than epoxy compounds include oxetane compounds and acrylic compounds.

Radical photopolymerization initiators and cationic photopolymerization initiators include those exemplified as the photopolymerization initiators described in the [Polarizing film] section. The content of the photoradical polymerization initiator and the photocationic polymerization initiator is usually 0.5 to 20 parts by mass, preferably 1 to 15 parts by mass, relative to 100 parts by mass of the active energy ray-curable adhesive. is.

Active energy ray-curable adhesives further contain ion trapping agents, antioxidants, chain transfer agents, tackifiers, thermoplastic resins, fillers, flow control agents, plasticizers, antifoaming agents, and the like. may

Examples of the active energy ray and irradiation conditions are the same as the active energy ray and irradiation conditions described in the section [Polarizing film].

Examples of the layer structure of the polarizing plate of the invention are shown below.
Structure (1) Polarizing plate structure consisting of optically anisotropic film/adhesive/substrate/alignment film/polarizing film (2) Optically anisotropic film/adhesive/substrate/alignment film/polarizing film Polarizing plate structure consisting of /protective layer (3) Polarizing plate structure consisting of optically anisotropic film/adhesive/polarizing film/orientation film/substrate (4) Optically anisotropic film/adhesive/protection Polarizing plate structure consisting of layer/polarizing film/alignment film/substrate (5) Optically anisotropic film/adhesive/substrate/alignment film/polarizing film/protective layer/adhesive/second optics Polarizing plate made of anisotropic film

The thickness of the polarizing plate of the present invention is preferably 10 to 300 μm, more preferably 20 to 200 μm, still more preferably 25 to 100 μm, from the viewpoint of flexibility and visibility of the display device.

The present invention includes a long polarizing plate in which the polarizing plate is made into a long shape. The length of the long polarizing plate in the long direction is, for example, 10 to 10,000 m, preferably 50 to 7,500 m, and more preferably 100 to 5,000 m.

The long polarizing plate of the present invention preferably has the following formulas (7), (8) and (9)
0° ≤ A ≤ 15° or 75° ≤ A ≤ 90° (7)
30°≦B≦60° (8)
0° ≤ C ≤ 15° or 75° ≤ C ≤ 90° (9)
[In the formula, A is the angle between the slow axis of the optically anisotropic film and the major axis direction of the long polarizing plate, and B is the angle between the absorption axis of the polarizing film and the major axis direction of the long polarizing plate. The angle C represents the angle between the slow axis of the second optically anisotropic film and the long axis direction of the long polarizing plate.]
meet. Arranging the optically anisotropic film, the polarizing film, and the second optically anisotropic film at such angles is advantageous in terms of visibility, antireflection of external light, and productivity. The formula (7) is more preferably 0 ° ≤ A ≤ 5 ° or 85 ° ≤ A ≤ 90 °, the formula (8) is more preferably 40 ° ≤ B ≤ 50 °, the formula (9) is 0°≦C≦5° or 85°≦C≦90°.

In the long polarizing plate satisfying the above formulas (7) to (8), for example, the angle A' between the slow axis and the major axis direction is the formula (7')
0°≦A′≦15° or 75°≦A′≦90° (7′)
A long optically anisotropic film that satisfies
The angle B' between the absorption axis and the long axis direction is given by formula (8')
30°≦B′≦60° (8′)
A long polarizing film that satisfies the formula (9') and the angle C' between the slow axis and the major axis direction is
0°≦C′≦15° or 75°≦C′≦90° (9′)
Prepare each long second optically anisotropic film that satisfies
It can be manufactured by a method of laminating them so that their long axis directions are aligned while conveying them in their long axis direction.

A long optically anisotropic film that satisfies the formula (7′) is prepared by applying a polymer varnish obtained by dissolving a polymer containing the polyimide polymer in a solvent to a long support to form a coating film. Step (1′) of drying the membrane to obtain a long polymer film with a support, and peeling off the long support from the obtained long polymer film with a support to obtain a long polymer film. A method comprising step (2′) and step (3′) of longitudinally stretching the long polymer film in the long axis direction or transversely stretching it in a direction orthogonal to the long axis direction, can be manufactured. The manufacturing conditions of steps (1') to (3') can be the same as those of steps (1) to (3).

A long optically anisotropic film that satisfies formula (7') can be obtained, for example, by longitudinally or laterally stretching a long polymer film in step (3'). This long polymer film contains a polyimide polymer. A polymer film containing a polyimide-based polymer exhibits the desired in-plane retardation Re (550) at a relatively low draw ratio. Therefore, a long optically anisotropic film obtained by stretching such a polymer film can control the direction of the slow axis and the in-plane retardation Re(550) with high accuracy even at a relatively low stretching ratio. It is preferable to manufacture by a method that can be obtained. Longitudinal stretching and transverse stretching, especially longitudinal stretching, can be manufactured by longitudinal stretching and transverse stretching because it is easy to control the slow axis and in-plane retardation with high accuracy even at a low draw ratio. In the above production method for producing a long polarizing plate using a long optically anisotropic film that satisfies the formula (7′), the slow axis and in-plane retardation Re (550) of the optically anisotropic film are This is advantageous in that a long polarizing plate with high accuracy can be manufactured.

The long polarizing film that satisfies the above formula (8′) may be, for example, a stretched film on which a dichroic dye is adsorbed. , A film comprising a dichroic dye and an oriented polymer of the polymerizable liquid crystal compound (B) can easily satisfy the above formula (8′) by controlling the orientation state of the polymerizable liquid crystal compound (B). , which is preferable because it can be produced without causing wrinkles or the like.

The long second optically anisotropic film that satisfies the above formula (9′) may be a film obtained by stretching or shrinking a polymer film. is preferred.

The present invention includes a laminate obtained by laminating a touch sensor on the polarizing plate of the present invention via an adhesive layer (hereinafter sometimes referred to as a touch sensor integrated polarizing plate). Specifically, the touch-sensor-integrated polarizing plate is attached to the outermost layer on the side opposite to the optically anisotropic film in the polarizing plates of the above configurations (1) to (5) via an adhesive layer. After peeling the base material of the polarizing plate of the above-described configuration (3) or (4), the touch sensor was laminated on the outermost alignment film via the adhesive layer. Configuration, and a configuration in which a touch sensor is laminated via an adhesive layer on the outermost polarizing film after peeling off the base material and the alignment film of the polarizing plate of the configuration (3) or (4) described above. are mentioned. The touch sensor integrated polarizing plate is suitably used for flexible display devices and the like.

[Touch sensor]
There are various types of touch sensors such as a resistive film type, a surface acoustic wave type, an infrared type, an electromagnetic induction type, and a capacitive type, but the capacitive type is preferable.
A capacitive touch sensor is divided into an active area and a non-active area located outside the active area. The active area is an area corresponding to the area (display part) where the screen is displayed on the display panel, and is an area where a user's touch is sensed. display area). The touch sensor comprises a flexible substrate; a sensing pattern formed in an active area of the substrate; and a touch sensor formed in a non-active area of the substrate and connected to an external driving circuit through the sensing pattern and pad portions. can include each sensing line for As the flexible substrate, the same material as the transparent substrate of the window can be used. The substrate of the touch sensor preferably has a toughness of 2,000 MPa % or more from the viewpoint of suppressing cracks in the touch sensor. More preferably, the toughness may be 2,000 MPa% to 30,000 MPa%.

The sensing patterns may include first patterns formed in a first direction and second patterns formed in a second direction. The first pattern and the second pattern are arranged in different directions. The first pattern and the second pattern are formed in the same layer, and each pattern must be electrically connected to sense a touched point. The first pattern has a form in which each unit pattern is connected to each other through a joint, but the second pattern has a structure in which each unit pattern is separated from each other in an island form. A separate bridge electrode is required for connection. A known transparent electrode material can be applied to the sensing pattern. For example, indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), indium zinc tin oxide (IZTO), cadmium tin oxide (CTO), PEDOT (poly(3,4- ethylenedioxythiophene), carbon nanotube (CNT), graphene, metal wire, etc., and these can be used alone or in combination of two or more. Preferably ITO can be used. The metal used for the metal wire is not particularly limited, and examples thereof include silver, gold, aluminum, copper, iron, nickel, titanium, terenium, and chromium. These can be used alone or in combination of two or more.

A bridge electrode may be formed on the insulating layer above the sensing pattern with an insulating layer interposed therebetween, and the bridge electrode may be formed on the substrate, and the insulating layer and the sensing pattern may be formed thereon. The bridge electrodes may be made of the same material as the sensing pattern, such as metals such as molybdenum, silver, aluminum, copper, palladium, gold, platinum, zinc, tin, titanium, or alloys of two or more thereof. You can also Since the first pattern and the second pattern should be electrically insulated, an insulating layer is formed between the sensing pattern and the bridge electrode. The insulating layer may be formed only between the joints and the bridge electrodes of the first pattern, or it may be formed in a structure of layers covering the sensing pattern. In the latter case, the bridge electrode can connect the second pattern through a contact hole formed in the insulating layer. The touch sensor is characterized by the difference in transmittance between patterned areas and non-patterned areas, specifically the difference in optical transmission induced by the difference in refractive index in these areas. An optical adjustment layer may be further included between the substrate and the electrode as a means for appropriately compensating for the difference, and the optical adjustment layer may include an inorganic insulating material or an organic insulating material. The optical adjustment layer may be formed by coating a photocurable composition containing a photocurable organic binder and a solvent on a substrate. The photocurable composition may further include inorganic particles. The inorganic particles may increase the refractive index of the optical adjustment layer.

The photocurable organic binder may include, for example, copolymers of monomers such as acrylate-based monomers, styrene-based monomers, and carboxylic acid-based monomers. The photocurable organic binder may be, for example, a copolymer containing different repeating units such as epoxy group-containing repeating units, acrylate repeating units, and carboxylic acid repeating units. The inorganic particles can include, for example, zirconia particles, titania particles, alumina particles, and the like. The photocurable composition may further include additives such as a photopolymerization initiator, a polymerizable monomer, and a curing aid.

The present invention includes a display device comprising the optically anisotropic film, the polarizing plate, or the touch sensor-integrated polarizing plate. The display device of the present invention comprises an optically anisotropic film having the adhesive layer on its surface, a polarizing plate having the adhesive layer on the surface, or a touch sensor integrated with the adhesive layer on the surface. A polarizing plate can be obtained by bonding it to the surface of a display device via the adhesive layer. A display device is a device having a display mechanism, and includes a light-emitting element or a light-emitting device as a light source. Examples of display devices include liquid crystal displays, organic electroluminescence (EL) displays, inorganic electroluminescence (EL) displays, electron emission displays (field emission displays (FED, etc.), surface field emission displays (SED)). , electronic paper (display device using electronic ink or electrophoretic element), plasma display device, projection type display device (grating light valve (GLV) display device, display device having digital micromirror device (DMD), etc.) and piezoelectric A ceramic display etc. are mentioned. The liquid crystal display device includes any of a transmissive liquid crystal display device, a transflective liquid crystal display device, a reflective liquid crystal display device, a direct view liquid crystal display device, a projection liquid crystal display device, and the like. These display devices may be display devices that display two-dimensional images, or may be stereoscopic display devices that display three-dimensional images. In particular, an organic EL display device is preferable as the display device of the present invention.

[Manufacturing of polyimide film]
Under a nitrogen atmosphere, 1.25 g of isoquinoline was charged to a reaction vessel connected to a vacuum pump fitted with a solvent trap and filter. Next, 375.00 g of γ-butyrolactone (GBL) and 104.12 g of 2,2′-bis(trifluoromethyl)-4,4′-diaminodiphenyl (TFMB) are added to the reaction vessel and the mixture is stirred. to dissolve. Further, 145.88 g of 4,4′-(hexafluoroisopropylidene)diphthalic dianhydride (6FDA) was added to the reaction vessel, and then the mixture was stirred and heated in an oil bath. The molar ratio of TFMB and 6FDA added was 1.00:0.99 and the monomer concentration in the mixture was 40% by weight. When the internal temperature of the reaction vessel reached 80°C, the pressure was reduced to 650 mmHg, and the internal temperature was subsequently raised to 180°C. After the internal temperature reached 180° C., the mixture was heated for another 4 hours while stirring. Thereafter, the pressure was restored to atmospheric pressure, and the internal temperature was cooled to 155° C. to obtain a polyimide solution. GBL was added at 155.degree. GPC measurement of the polyimide in the obtained polyimide varnish revealed that the weight average molecular weight was 360,000. Moreover, the fluorine atom content of the polyimide was 31.3% by mass.

38.31 g of GBL and 11.82 g of N,N-dimethylacetamide (DMAc) were added to 200.00 g of the above polyimide varnish for further dilution. Using the diluted polyimide varnish, a coating film was formed on a PET (polyethylene terephthalate) film by casting. After that, the coating film was dried by heating at 50° C. for 30 minutes and at 140° C. for 10 minutes to obtain a polyimide film with a PET film. The PET film was peeled off from the obtained polyimide film with PET film to obtain a polyimide film.

[Optical Anisotropic Films 1 and 2]
The polyimide film obtained above was uniaxially stretched at a stretching temperature of 200° C. and a stretching ratio of 1.055 to obtain a stretched polyimide film having a thickness of 60 μm. A center portion of the stretched polyimide film was cut out, and the in-plane retardation at a wavelength of 550 nm was measured to be 150 nm. This film was referred to as an optically anisotropic film 1. Moreover, when the edge of the stretched polyimide film was cut out and the in-plane retardation at a wavelength of 550 nm was measured, it was 127 nm. This film was designated as an optically anisotropic film 2 . In the examples, the in-plane retardation at a wavelength of 550 nm was measured using KOBRA-WR manufactured by Oji Scientific Instruments.

[Optical anisotropic film 3]
The polyimide film obtained above was uniaxially stretched at a stretching temperature of 200° C. and a stretching ratio of 1.082 to obtain a stretched polyimide film having a thickness of 60 μm. A center portion of the stretched polyimide film was cut out, and the in-plane retardation at a wavelength of 550 nm was measured to be 284 nm. This film was referred to as an optically anisotropic film 3.

[Optical anisotropic film 4]
The polyimide film obtained above was uniaxially stretched at a stretching temperature of 200° C. and a stretching ratio of 1.050 to obtain a stretched polyimide film having a thickness of 60 μm. A center portion of the stretched polyimide film was cut out, and the in-plane retardation at a wavelength of 550 nm was measured to be 29 nm. This film was designated as an optically anisotropic film 4 .

溶剤（９８部）：o-キシレン[Production of Composition for Forming Photo-Alignment Film]
A composition for forming a photo-alignment film was obtained by mixing the following components in the following proportions and stirring the resulting mixture at 80° C. for 1 hour.
[Photo-orientation material (2 parts)]:

Solvent (98 parts): o-xylene

[Production of composition for forming polarizing film]
The following components were mixed in the following proportions, and the resulting mixture was stirred at 80° C. for 1 hour to obtain a composition for forming a polarizing film. As the dichroic dye, an azo dye described in Examples of JP-A-2015-165302 was used.

〔二色性色素〕

〔他の成分〕
重合開始剤；
２－ジメチルアミノ－２－ベンジル－１－（４－モルホリノフェニル）ブタン－１－オン（イルガキュア３６９；チバスペシャルティケミカルズ社製）
６部
レベリング剤；
ポリアクリレート化合物（「ＢＹＫ－３６１Ｎ」、ＢＹＫ－Ｃｈｅｍｉｅ社製） １．２部
溶剤；o-キシレン ２５０部[Polymerizable liquid crystal compound]

[Dichroic dye]

[Other ingredients]
polymerization initiator;
2-dimethylamino-2-benzyl-1-(4-morpholinophenyl)butan-1-one (Irgacure 369; manufactured by Ciba Specialty Chemicals)
6 parts a leveling agent;
Polyacrylate compound ("BYK-361N", manufactured by BYK-Chemie) 1.2 parts Solvent; o-xylene 250 parts

[Measurement of phase transition temperature]
A 2% by mass aqueous solution of polyvinyl alcohol (“polyvinyl alcohol 1000”, fully saponified type, manufactured by Wako Pure Chemical Industries, Ltd.) (rubbing alignment film forming composition) was applied onto a glass substrate by a spin coating method and dried. After that, a film with a thickness of 100 nm was formed. Subsequently, a rubbed alignment film was formed by performing a rubbing treatment on the surface of the obtained film. The rubbing treatment is performed using a semi-automatic rubbing device (“LQ-008 type”, manufactured by Joyo Engineering Co., Ltd.) with a cloth (“YA-20-RW”, manufactured by Yoshikawa Kako Co., Ltd.) with a pushing amount of 0.15 mm and rotation. It was performed under the conditions of several 500 rpm and 16.7 mm/s. The polarizing film-forming composition (A) was applied on the rubbing alignment film thus prepared by spin coating, dried by heating on a hot plate at 120° C. for 1 minute, and then quickly cooled to room temperature. A dry film was formed on the rubbed alignment film. After the temperature of the dried coating was again raised to 120° C. on a hot plate, the phase transition temperature was measured by observing with a polarizing microscope while the temperature was lowered. As a result, it was confirmed that the phase transitioned to the nematic phase at 115°C, to the smectic A phase at 105°C, and to the smectic B phase at 74°C.

[X-ray diffraction measurement]
The composition for forming a polarizing film is applied onto the rubbed alignment film by a spin coating method, dried by heating on a hot plate at 120° C. for 1 minute, then quickly cooled to room temperature, and dried onto the rubbed alignment film. A coating was formed. Next, using a UV irradiation device (“SPOT CURE SP-7”, manufactured by Ushio Inc.), the dry film is irradiated with ultraviolet light at an exposure amount of 2000 mJ/cm ² (365 nm standard) to remove the impurities contained in the dry film. The polymerizable liquid crystal compound was polymerized while maintaining the liquid crystal state of the polymerizable liquid crystal composition, and a polarizing film was formed from the dried film. When the thickness of the polarizing film at this time was measured with a laser microscope (OLS3000 manufactured by Olympus Corporation), it was 1.7 μm. This polarizing film was similarly subjected to X-ray diffraction measurement using an X-ray diffractometer X'Pert PRO MPD (manufactured by Spectris Co., Ltd.). ) = about 0.312°, a sharp diffraction peak was obtained. Similar results were also obtained with incident light perpendicular to the rubbing direction. The ordered period (d) determined from the peak position was about 4.4 Å, confirming that a structure reflecting a higher-order smectic phase was formed.

[Preparation of polarizing film]
A 40 μm-thick triacetyl cellulose film (TAC) [“KC4UA” manufactured by Konica Minolta Opto Co., Ltd. is used as a base material, and the surface of the base material is treated with a corona treatment device (“AGF-B10”, manufactured by Kasuga Denki Co., Ltd.). The treatment was performed once under the conditions of an output of 0.3 kW and a treatment speed of 3 m/min. A composition for forming a photo-alignment film was applied to the corona-treated surface by a bar coater, dried at 80° C. for 1 minute, and irradiated with a polarized UV irradiation device (“SPOT CURE SP-”, manufactured by Ushio Inc.). , and an integrated light dose of 100 mJ/cm ² , polarized UV exposure was performed at an axial angle of 90°. It was 100 nm when the film thickness of the obtained photo-alignment film was measured with an ellipsometer.
After applying the composition for forming a polarizing film using a bar coater, by drying for 1 minute in a drying oven set to 120 ° C., the polymerizable liquid crystal compound and the dichroic dye were oriented dry coating film was obtained. After naturally cooling this dry coating film to room temperature, a high-pressure mercury lamp ("Unicure VB-15201BY-A", manufactured by Ushio Inc.) is used to irradiate ultraviolet rays (under nitrogen atmosphere, wavelength: 365 nm, integration at wavelength 365 nm Light amount: 1000 mJ/cm ² ) to polymerize the polymerizable liquid crystal compound to produce a polarizing film. It was 3.1 nm when the film thickness of the obtained polarizing film was measured with an ellipsometer. Thus, a laminate A was obtained in which substrate/photo-alignment film/polarizing film were laminated in this order.

[Measurement of single transmittance]
Using the optically anisotropic film and laminate A obtained above, the single transmittance was measured as follows. Using a spectrophotometer (“UV-3150”, manufactured by Shimadzu Corporation) with a polarizer-equipped folder set, measurement was performed in a wavelength range of 380 to 680 nm in 2 nm steps by the double beam method. For the measurement, a polarizing plate having an optically anisotropic film and a laminate A (substrate/photo-alignment film/polarizing film) in this order was placed behind a polarizer set in a folder. The angle between the absorption axis of the polarizer set in the folder and the slow axis of the optically anisotropic film was defined as θa, and the angle between the absorption axis of the polarizer set in the folder and the absorption axis of the polarizing film was defined as θb. Further, luminosity correction was performed using a JIS Z 8701 2-degree field of view (C light source), and luminosity-corrected single transmittance (Ty) was calculated.

[Example 1]
Optically anisotropic film 1 was used as the optically anisotropic film, θa was set to 45°, and θb was set to 0°, 30°, 60°, and 90°, and the single transmittance was measured and visibility was corrected. Visibility-corrected single transmittance (Ty) was calculated. Table 1 shows the results. Even when θb was changed to 0°, 30°, 60°, and 90°, Ty was maintained at 30% or more, and the visibility was good.

[Example 2]
The single transmittance was measured in the same manner as in Example 1 except that the optically anisotropic film 2 was used as the optically anisotropic film. .
Table 1 shows the results. Even when θb was changed to 0°, 30°, 60°, and 90°, Ty was maintained at 30% or more, and the visibility was good.

[Comparative Example 1]
Except for using the optically anisotropic film 3 as the optically anisotropic film, the single transmittance was measured in the same manner as in Example 1, the luminosity correction was performed, and the luminosity corrected single transmittance (Ty) was calculated. .
Table 1 shows the results. When θb was set to 0°, Ty became 3%, and there was a problem with visibility.

[Comparative Example 2]
Except for using the optically anisotropic film 4 as the optically anisotropic film, the single transmittance was measured in the same manner as in Example 1, the luminosity correction was performed, and the luminosity corrected single transmittance (Ty) was calculated. .
Table 1 shows the results. When θb was set to 90°, Ty became 2%, and there was a problem with visibility.

[Comparative Example 3]
As an optically anisotropic film, a laminate obtained by laminating a cyclic polyolefin film (“Zeonor Film ZF35-Film #140”, thickness 28 μm) manufactured by Nippon Zeon Co., Ltd. on the optically anisotropic film 4 of Comparative Example 2 was used. The single transmittance was measured in the same manner as in Example 1 except that it was used, the luminosity correction was performed, and the luminosity corrected single transmittance (Ty) was calculated. Table 1 shows the results.
When θb was set to 0°, 30° and 60°, Ty became 26%, 19% and 26%, respectively, and there was a problem in visibility. In addition, the thickness of the cyclic polyolefin film is increased.

As shown in Table 1, the in-plane retardation of the optically anisotropic film at a wavelength of 550 nm satisfies 100 nm≦Re(550)≦160 nm. Even if there is, the visibility correction single transmittance (Ty) is 30% or more, and it was confirmed that the visibility is excellent. This indicates that, for example, when viewing a display device including the optically anisotropic film or the polarizing plate while wearing polarized sunglasses, visibility is good even when the angle of the display device is changed. On the other hand, in the polarizing plates of Comparative Examples 1 to 3, in which the in-plane retardation at a wavelength of 550 nm of the optically anisotropic film is outside the range of 100 nm≦Re(550)≦160 nm, the angle θb is 0°, Ty was less than 30% at any of 30°, 60° and 90°, and it was confirmed that there was a problem with visibility.

Claims (6)

A polarizing plate obtained by laminating an optically anisotropic film as a front plate of a display device, a polarizing film, and a second optically anisotropic film in this order,
The optically anisotropic film contains a polyimide polymer and has the following formula (1)
80 nm≦Re(550)≦160 nm (1)
[Wherein, Re (550) represents an in-plane retardation at a wavelength of 550 nm]
The filling,
The second optically anisotropic film is represented by the following formulas (3), (4) and (5)
100 nm≦Re(550)≦160 nm (3)
Re(450)/Re(550)≤1.0 (4)
1.00≦Re(650)/Re(550) (5)
[Wherein, Re (450), Re (550) and Re (650) represent in-plane retardation at wavelengths of 450 nm, 550 nm and 650 nm, respectively]
satisfies the
A polarizing plate comprising an oriented polymer of a polymerizable liquid crystal compound having a smectic phase and containing a dichroic dye . The angle θ1 between the slow axis of the optically anisotropic film and the absorption axis of the polarizing film is expressed by the following formula (2)
30°≤θ1≤60° (2)
The polarizing plate according to claim 1, which satisfies: The angle θ2 between the slow axis of the second optically anisotropic film and the absorption axis of the polarizing film is expressed by the following formula (6)
30°≤θ2≤60° (6)
3. The polarizing plate according to claim 1 , which satisfies: A long polarizing plate obtained by making the polarizing plate according to any one of claims 1 to 3 into a long shape,
Formulas (7), (8) and (9) below
0° ≤ A ≤ 15° or 75° ≤ A ≤ 90° (7)
30°≦B≦60° (8)
0° ≤ C ≤ 15° or 75° ≤ C ≤ 90° (9)
[In the formula, A is the angle between the slow axis of the optically anisotropic film and the major axis direction of the long polarizing plate, and B is the angle between the absorption axis of the polarizing film and the major axis direction of the long polarizing plate. The angle C represents the angle between the slow axis of the second optically anisotropic film and the long axis direction of the long polarizing plate.]
A long polarizing plate that satisfies A laminate in which the polarizing plate according to any one of claims 1 to 4 and a touch sensor are laminated via an adhesive layer. A display device comprising the polarizing plate according to any one of claims 1 to 4 or the laminate according to claim 5 .