JP2002062427A - Liquid crystal alignment layer, method for aligning rod- shaped liquid crystalline molecule, optical compensation sheet, polarizing plate and modified polyvinyl alcohol - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystal alignment layer having a function to vertically align rod-shaped liquid crystal molecules with respect to a rubbing direction. SOLUTION: The alignment layer is formed by using a modified polyvinyl alcohol containing a recurring unit corresponding to vinyl alcohol and a recurring unit having a ring structure directly connected to a main chain.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a liquid crystal alignment film. In addition, the present invention relates to a method for aligning rod-like liquid crystalline molecules perpendicular to a rubbing direction using an alignment film. Furthermore, the present invention also relates to an optical compensatory sheet having, in this order, an alignment film and an optically anisotropic layer formed of rod-like liquid crystalline molecules on a transparent support, and a polarizing plate using the same. Furthermore, the present invention also relates to a modified polyvinyl alcohol having an alignment function.

[0002]

2. Description of the Related Art A liquid crystal display device comprises a liquid crystal cell, a polarizing element, and an optical compensation sheet (retardation plate). In a transmission type liquid crystal display device, two polarizing elements are attached to both sides of a liquid crystal cell, and one or two optical compensation sheets are arranged between the liquid crystal cell and the polarizing element. In a reflection type liquid crystal display device, a reflection plate, a liquid crystal cell, one optical compensation sheet, and one polarization element are arranged in this order. The liquid crystal cell includes a rod-like liquid crystal molecule layer, two substrates for enclosing the same, an electrode layer for applying a voltage to the rod-like liquid crystal molecules, and an alignment film layer for controlling the alignment of the rod-like liquid crystal molecules. The liquid crystal cell has a different alignment state of rod-like liquid crystal molecules.
(Twisted Nematic), IPS (In-Plane Switchin)
g), FLC (Ferroelectric Liquid Crystal), OC
B (Optically Compensatory Bend), STN (Supper
Twisted Nematic), VA (Vertically Aligned), E
CB (Electrically Controlled Birefringence), TN and HAN (Hybrid Aligned Nemat)
ic) and various display modes such as GH (Guest-Host).

[0003] Optical compensatory sheets are used in various liquid crystal display devices in order to eliminate coloring of images and to increase the viewing angle. As the optical compensation sheet, a stretched birefringent polymer film has been conventionally used. It has been proposed to use an optical compensatory sheet having an optically anisotropic layer formed of liquid crystal molecules on a transparent support instead of an optical compensatory sheet made of a stretched birefringent film. Since liquid crystal molecules have various alignment forms, it has become possible to realize optical properties that cannot be obtained by a conventional stretched birefringent polymer film by using liquid crystal molecules.

[0004] The optical properties of the optical compensatory sheet are determined according to the optical properties of the liquid crystal cell, specifically, the above-mentioned difference in display mode. When liquid crystal molecules are used, an optical compensation sheet having various optical properties corresponding to various display modes of a liquid crystal cell can be manufactured. Generally, rod-like liquid crystal molecules or discotic liquid crystal molecules are used as the liquid crystal molecules. As the optical compensation sheet using liquid crystal molecules, ones corresponding to various display modes have already been proposed. For example, an optical compensation sheet for a TN mode liquid crystal cell is disclosed in JP-A-6-214116,
It is described in U.S. Pat. Nos. 5,583,679 and 5,646,703 and German Patent Publication No. 391620A1. An optical compensatory sheet for a liquid crystal cell in the IPS mode or the FLC mode is described in JP-A-10-54982. Further, an optical compensatory sheet for a liquid crystal cell of OCB mode or HAN mode is disclosed in US Pat.
No. 3 and International Patent Application WO 96/37804. Further, an optical compensatory sheet for a liquid crystal cell in the STN mode is described in JP-A-9-26572. An optical compensation sheet for a VA mode liquid crystal cell is described in Japanese Patent No. 2866372.

[0005]

SUMMARY OF THE INVENTION An optical compensatory sheet having an optically anisotropic layer formed from rod-like liquid crystalline molecules,
The average direction of the line obtained by projecting the major axis direction of the rod-like liquid crystal molecules onto the surface of the transparent support corresponds to the slow axis of the optical compensation sheet. The average direction of the line obtained by projecting the major axis direction of the rod-like liquid crystal molecules onto the surface of the transparent support generally corresponds to the rubbing direction of the alignment film. The optical compensatory sheet is in the form of a roll in actual production, and the rubbing treatment is most easily performed in the longitudinal direction of the roll-shaped optical compensatory sheet. Therefore, in an optical compensatory sheet having an optically anisotropic layer formed from rod-like liquid crystalline molecules, an embodiment having a slow axis in the longitudinal direction can be most easily produced. The transmission axis of the polarizing film corresponds to a direction perpendicular to the stretching direction of the polymer film forming the polarizing film. The polarizing element is also in a roll shape in actual production, and it is easiest to perform the stretching process in the longitudinal direction of the roll-shaped polarizing film. Accordingly, a polarizing element having a transmission axis in a direction (width direction) perpendicular to the longitudinal direction can be most easily produced.

From the above relationship, when laminating the roll-shaped optical compensation sheet and the roll-shaped polarizing element, the slow axis of the optical compensation sheet and the transmission axis of the polarizing film are arranged so as to be substantially perpendicular to each other. Is the easiest to produce. On the other hand, depending on the display mode of the liquid crystal cell, it may be preferable to arrange the slow axis of the optical compensation sheet and the transmission axis of the polarizing film so as to be substantially parallel. In order for the slow axis of the roll-shaped optical compensatory sheet to be in the width direction of the optical compensatory sheet, it is necessary to align the rod-like liquid crystalline molecules such that the major axis direction is perpendicular to the rubbing direction of the alignment film. is there. In the present specification, "the major axis direction of the rod-shaped liquid crystalline molecules is perpendicular to the rubbing direction of the alignment film" means that the average direction of a line obtained by projecting the major axis direction of the rod-shaped liquid crystalline molecules on the transparent support surface is referred to. ,
It means perpendicular to the rubbing direction. In order to align the rod-like liquid crystal molecules so as to be perpendicular to the rubbing direction, an alignment film having such an alignment function is required. The conventional alignment film has a function of aligning the rod-like liquid crystal molecules in parallel with the rubbing direction.

An object of the present invention is to provide a liquid crystal alignment film having a function of aligning rod-like liquid crystal molecules perpendicular to a rubbing direction. Another object of the present invention is to align rod-like liquid crystal molecules perpendicular to the rubbing direction. Still another object of the present invention is to provide a roll-shaped optical compensation sheet having a slow axis in the width direction. Still another object of the present invention is to provide a polarizing plate that can be easily arranged such that the slow axis of the optical compensation sheet and the transmission axis of the polarizing film are substantially parallel.

[0008]

An object of the present invention is to provide a liquid crystal alignment film of the following (1) to (3), a method of aligning rod-like liquid crystal molecules of the following (4) to (8), and the following (9). And the polarizing plate of the following (10) and the modified polyvinyl alcohol of the following (11). (1) a liquid crystal alignment film provided on a support,
A liquid crystal alignment film comprising a modified polyvinyl alcohol containing a repeating unit represented by the following formula (I) and a repeating unit represented by the following formula (II):

[0009]

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Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms;
Is an aliphatic, aromatic or heterocyclic group; m
Is 10 to 95 mol%; and n is 5 to 90 mol%]. (2) The liquid crystal alignment film according to (1), wherein the modified polyvinyl alcohol further has a polymerizable group. (3) The modified polyvinyl alcohol further has the following formula (II)
The liquid crystal alignment film according to (1), containing the repeating unit represented by I).

[0011]

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[0012] [wherein, R ² represents a hydrogen atom, a halogen atom or a carbon atoms is an alkyl group of 1 to 6; L ¹
Is a single bond or a divalent linking group; Q is a polymerizable group; and l is 0.1 to 20 mol%.

(4) Coating a modified polyvinyl alcohol containing a repeating unit represented by the formula (I) and a repeating unit represented by the formula (II) on a support to form a coating layer; The surface of the layer is rubbed to form an alignment film; and a coating solution containing rod-like liquid crystal molecules is applied on the alignment film and dried, so that the major axis direction of the rod-like liquid crystal molecules is changed to the transparent support surface. A method in which rod-like liquid crystalline molecules are aligned so that the average direction of lines obtained by projection on the substrate and the rubbing direction of the alignment film are substantially orthogonal to each other. (5) The rod-shaped liquid crystal molecules have a polymerizable group, and after the rod-shaped liquid crystal molecules are aligned, the rod-shaped liquid crystal molecules are polymerized to fix the alignment state. (4) The rod-shaped liquid crystal molecules are aligned. How to let.

(6) The support has a roll shape, and the average direction of a line obtained by projecting the major axis direction of the rod-like liquid crystalline molecules onto the support surface is substantially orthogonal to the longitudinal direction of the support. (4) The method for aligning rod-like liquid crystalline molecules according to (4). (7) The method according to (4), wherein the support has a roll shape, and the rubbing direction of the alignment film is substantially parallel to the longitudinal direction of the support. (8) The method according to (4), wherein the rod-like liquid crystal molecules are oriented in a state where the average inclination angle between the major axis direction of the rod-like liquid crystal molecules and the support surface is less than 5 °.

(9) A roll-shaped optical compensation sheet having a transparent support, an alignment film and an optically anisotropic layer formed of rod-like liquid crystalline molecules in this order, wherein the alignment film is of the formula (I) A modified polyvinyl alcohol containing a repeating unit represented by the formula (II) and a repeating unit represented by the formula (II), and the average direction of a line obtained by projecting the major axis direction of the rod-shaped liquid crystalline molecules onto the surface of the transparent support. An optical compensatory sheet characterized in that the rod-like liquid crystalline molecules are oriented so that the rubbing direction of the orientation film is substantially perpendicular to the rubbing direction. (10) A roll-shaped polarizing plate having an optically anisotropic layer formed from rod-shaped liquid crystalline molecules, an alignment film, a transparent support, a polarizing film and a transparent protective film, wherein the alignment film is of the formula (I) ) And a modified polyvinyl alcohol containing a repeating unit represented by the formula (II), wherein the average tilt angle between the major axis direction of the rod-like liquid crystalline molecules and the transparent support surface is 5 °. The rod-like liquid crystal molecules are oriented in a state of less than, and the average direction of the line obtained by projecting the major axis direction of the rod-like liquid crystal molecules on the transparent support surface and the longitudinal direction of the polarizing plate are substantially orthogonal. A polarizing plate, wherein a transmission axis of the polarizing film and an average direction of a line obtained by projecting a major axis direction of the rod-like liquid crystal molecules onto the surface of the transparent support are substantially parallel to each other.

(11) A modified polyvinyl alcohol containing a repeating unit represented by the above formula (I), a repeating unit represented by the above formula (II) and a repeating unit represented by the above formula (III). In addition, in this specification, substantially parallel or substantially orthogonal means that the angle difference between the strict parallel and the strict orthogonal is less than 5 °. Preferably, the angle difference is less than 4 °, more preferably less than 3 °, even more preferably less than 2 °, and most preferably less than 1 °.

[0017]

As a result of the research conducted by the present inventors, when a modified polyvinyl alcohol containing a repeating unit represented by the above formula (I) and a repeating unit represented by the above formula (II) is used for a liquid crystal alignment film, It has been found that the rod-like liquid crystalline molecules can be uniformly aligned so as to be substantially perpendicular to the rubbing direction. Thereby, an optical compensation sheet in which the rod-like liquid crystalline molecules are oriented substantially perpendicular to the rubbing direction can be manufactured. Therefore, it has become possible to easily produce a roll-shaped optical compensation sheet having a slow axis in a direction (width direction) perpendicular to the longitudinal direction. On the other hand, as described above, a roll-shaped polarizing element having a transmission axis in a direction perpendicular to the longitudinal direction (width direction) can be most easily produced. Therefore, by laminating the roll-shaped optical compensation sheet and the roll-shaped polarizing element according to the present invention in a roll state, a polarizing plate having a slow axis of the optical compensation sheet and a transmission axis of the polarizing film substantially parallel to each other. Can be produced. As described above, by using the optical compensation sheet according to the present invention, the optical compensation sheet can be easily arranged such that the slow axis of the optical compensation sheet and the transmission axis of the polarizing film are substantially parallel.

[0018]

FIG. 1 is a schematic diagram showing the basic structure of a transmission type liquid crystal display device. The transmission type liquid crystal display device shown in FIG. 1A includes a transparent protective film (1a), a polarizing film (2a), a transparent support (3a), and an optically anisotropic layer in order from the backlight (BL) side. (4a), lower substrate (5a) of liquid crystal cell, rod-like liquid crystalline molecular layer (6), upper substrate of liquid crystal cell (5b), optically anisotropic layer (4b), transparent support (3
b), a polarizing film (2b), and a transparent protective film (1b). The transparent support and the optically anisotropic layers (3a to 4a and 4b to 3b) constitute an optical compensation sheet. Then, the transparent protective film, the polarizing film, the transparent support, and the optically anisotropic layers (1a to 4a and 4b to 1b) constitute a polarizing plate. The transparent support (3a, 3b) comprises an optically anisotropic layer (4
a) An alignment film is provided on the 4b) side. In addition, the lower substrate (5a) and the upper substrate (5b) of the liquid crystal cell also have an alignment film on the side of the rod-shaped liquid crystalline molecular layer (6).

The transmission type liquid crystal display device shown in FIG. 1B has a transparent protective film (1) in order from the backlight (BL) side.
a), a polarizing film (2a), a transparent support (3a), an optically anisotropic layer (4a), a lower substrate (5a) of a liquid crystal cell, a rod-shaped liquid crystalline molecular layer (6), and an upper substrate of a liquid crystal cell ( 5b), the transparent protective film (1b), the polarizing film (2b), and the transparent protective film (1
c). Transparent support and optically anisotropic layer (3a
4a) constitute an optical compensation sheet. Then, a transparent protective film, a polarizing film, a transparent support and an optically anisotropic layer (1a
To 4a) constitute a polarizing plate. The transparent support (3a)
An alignment film is provided on the optically anisotropic layer (4a) side. In addition, the lower substrate (5a) and the upper substrate (5b) of the liquid crystal cell also have an alignment film on the side of the rod-shaped liquid crystalline molecular layer (6).

The transmission type liquid crystal display device shown in FIG. 1C has a transparent protective film (1) in order from the backlight (BL) side.
a), a polarizing film (2a), a transparent protective film (1b), a lower substrate (5a) of a liquid crystal cell, a rod-like liquid crystalline molecular layer (6), an upper substrate (5b) of a liquid crystal cell, and an optically anisotropic layer ( 4b), a transparent support (3b), a polarizing film (2b), and a transparent protective film (1
c). Transparent support and optically anisotropic layer (4b
3b) constitute an optical compensation sheet. Then, a transparent protective film, a polarizing film, a transparent support, and an optically anisotropic layer (4b
To 1c) constitute a polarizing plate. The transparent support (3b)
An alignment film is provided on the optically anisotropic layer (4b) side. In addition, the lower substrate (5a) and the upper substrate (5b) of the liquid crystal cell also have an alignment film on the side of the rod-shaped liquid crystalline molecular layer (6).

FIG. 2 is a schematic diagram showing a basic configuration of a reflection type liquid crystal display device. The reflection type liquid crystal display device shown in FIG. 2 includes, in order from the bottom, a lower substrate (5a) of a liquid crystal cell, a reflector (RP), a rod-like liquid crystal molecular layer (6), an upper substrate (5b) of the liquid crystal cell, Anisotropic layer (4), transparent support (3),
It comprises a polarizing film (2) and a transparent protective film (1). The transparent support and the optically anisotropic layer (4 to 3) constitute an optical compensation sheet. Then, the transparent protective film, the polarizing film, the transparent support, and the optically anisotropic layer (4-1) constitute a polarizing plate. The transparent support (3) has an alignment film on the optically anisotropic layer (4) side. Further, the reflection plate (RP) and the upper substrate (5b) of the liquid crystal cell also have an alignment film on the rod-like liquid crystal molecular layer (6) side.

FIG. 3 is a schematic view showing a step of bonding a roll-shaped polarizing element and a roll-shaped optical compensation sheet. As shown in FIG. 3, the roll-shaped polarizing element includes a transparent protective film (1) and a polarizing film (2). The roll-shaped optical compensation sheet comprises a transparent support (3) and an optically anisotropic layer (4). The transparent support (3) has an alignment film on the optically anisotropic layer (4) side. The transmission axis of the polarizing film (2) (T
A) is substantially orthogonal to the longitudinal direction (LD) of the roll-shaped polarizing element. The average direction of the line obtained by projecting the major axis direction of the rod-like liquid crystalline molecules of the optically anisotropic layer (4) onto the transparent support surface, that is, the slow axis (SA) is the longitudinal direction of the roll-shaped optical compensation sheet. (LD) is substantially orthogonal. Therefore, as shown in FIG. 3, the transmission axis (TA) of the polarizing film (2) and the retardation of the optically anisotropic layer (4) can be obtained simply by bonding the roll-shaped polarizing element and the roll-shaped optical compensation sheet as they are. It can be arranged such that the phase axis (SA) is substantially parallel. 1 to 3, the order of the transparent support (3) and the optically anisotropic layer (4) may be reversed.

[Alignment Film] The alignment film is composed of a modified polyvinyl alcohol containing a repeating unit represented by the following formula (I) and a repeating unit represented by the following formula (II).

[0024]

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In the formula (I), m is from 10 to 95 mol%. In the formula (II), R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms. R ¹ is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom, methyl or ethyl, and most preferably a hydrogen atom or methyl.

In the formula (II), Cy represents an aliphatic cyclic group,
It is an aromatic group or a heterocyclic group. The aliphatic ring of the aliphatic ring group is preferably a 5- to 7-membered ring, more preferably a 5- or 6-membered ring, and most preferably a 6-membered ring. Examples of the aliphatic ring include a cyclohexane ring, a cyclohexene ring, and a bicyclo [2.2.1] hept-2-ene ring. Another aliphatic ring, aromatic ring or heterocyclic ring may be condensed to the aliphatic ring. Examples of the aromatic ring of the aromatic group include a benzene ring, a naphthalene ring,
Includes anthracene, phenanthrene, pyrene and naphthacene rings. An aliphatic ring or a heterocyclic ring may be fused to the aromatic ring. The heterocyclic ring of the heterocyclic group is preferably a 5- to 7-membered ring, more preferably a 5- or 6-membered ring. The heterocyclic ring preferably has aromaticity. The aromatic heterocycle is generally unsaturated and preferably has the most double bonds. Examples of the heterocyclic ring, furan ring, thiophene ring, pyrrole ring, oxazole ring, isoxazole ring, isothiazole ring, imidazole ring, pyrazole ring, furazane ring, pyran ring,
Includes pyridine, pyridazine, pyrimidine and pyrazine rings. Another heterocyclic ring, aliphatic ring or aromatic ring may be fused to the heterocyclic ring.

An aliphatic ring group, an aromatic group and a heterocyclic group are
It may have a substituent. Examples of the substituent include an alkyl group (eg, methyl, ethyl, t-butyl), a substituted alkyl group (eg, chloromethyl, hydroxymethyl, trimethylammonio chloride), an alkoxy group (eg, methoxy), a halogen atom (eg, F, Cl, Br), carboxyl, acyl group (eg, formyl), amino, sulfo, aryl group (eg, phenyl), aryloxy group (eg, phenoxy) and oxo. In the formula (II), n
Is 5 to 90 mol%. Examples of the repeating unit represented by the formula (II) are shown below.

[0028]

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[0029]

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[0030]

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[0031]

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[0032]

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The modified polyvinyl alcohol preferably further has a polymerizable group. The polymerizable group may be introduced into the modified polyvinyl alcohol as a repeating unit having a polymerizable group in the side chain, or may be added to the aliphatic, aromatic, or heterocyclic group of the repeating unit represented by the formula (II). Introduced as a substituent. The repeating unit having a polymerizable group in the side chain is preferably represented by the following formula (III).

[0034]

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In the formula (III), R ² is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms. R ² is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom, methyl or ethyl, and most preferably a hydrogen atom or methyl.

In the formula (III), L ¹ is a single bond or a divalent linking group. Divalent linking groups are preferred over single bonds. The divalent linking group is -O-, -CO-, -NH
It is preferable to be selected from-, -alkylene group-, -arylene group- and a combination thereof. Examples of the divalent linking group include -O-CO-, -O-CO-NH-, -O
-CO-NH-alkylene group-, -O-CO-NH-alkylene group-O-, -O-CO-NH-alkylene group-
CO-O-, -O-CO-NH-alkylene group -OC
O-, -O-CO-NH-alkylene group -CO-NH
-, -O-CO-alkylene group -O-CO-, -OC
O-arylene group-O-alkylene group-O-CO-,-
O-CO-arylene group-O-alkylene group-O-,-
O-CO-arylene group-O-alkylene group- and-
O-alkylene group -O-CO- is included (the left side is bonded to the main chain, and the right side is bonded to the polymerizable group). The alkylene group may have a branched or cyclic structure. The number of carbon atoms of the alkylene group is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 1.
More preferably, it is 5 and most preferably 1 to 12. The arylene group is preferably phenylene or naphthylene, more preferably phenylene, and most preferably p-phenylene. The arylene group may have a substituent. Examples of the substituent of the arylene group are the same as the examples of the substituent of the aliphatic ring group, the aromatic group, and the heterocyclic group. As a substituent, Q may have another polymerizable group. The repeating unit represented by the formula (III) may have two or more polymerizable groups.

In the formula (III), Q is a polymerizable group. The polymerizable group is a polymerizable group (Q) of a liquid crystal molecule described below.
And the (meth) acrylic acid copolymer and the rod-like liquid crystal molecules are chemically bonded via the interface between the alignment film and the optically anisotropic layer. Therefore, the type of the polymerizable group is determined according to the type of the polymerizable group (Q) of the rod-like liquid crystal molecule described below. The polymerizable group (Q) of the rod-like liquid crystalline molecule is
As described below, an unsaturated polymerizable group (Q1 described below)
To Q7), an epoxy group (Q8) or an aziridinyl group (Q9), more preferably an unsaturated polymerizable group, and more preferably an ethylenically unsaturated polymerizable group (Q
1 to Q6) are most preferred. Similarly, the polymerizable group of the (meth) acrylic acid copolymer is an unsaturated polymerizable group,
It is preferably an epoxy group or an aziridinyl group, more preferably an unsaturated polymerizable group, and most preferably an ethylenically unsaturated polymerizable group.

In the formula (III), 1 is 1 to 20 mol%. Hereinafter, examples of the repeating unit represented by the formula (III) are shown.

[0039]

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[0040]

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[0041]

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[0042]

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[0043]

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[0044]

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When a polymerizable group is introduced as a substituent into the aliphatic ring group, aromatic group and heterocyclic group of the repeating unit represented by the formula (II), the polymerizable group is not directly linked to the cyclic structure,
It is preferable to bond through a divalent linking group. The definition and examples of the divalent linking group are the same as those of L in the formula (III). Examples of the repeating unit (IV) in which a polymerizable group is introduced as a substituent into the aliphatic ring group, aromatic group, and heterocyclic group of the repeating unit represented by the formula (II) are shown.

[0046]

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[0047]

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[0048]

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[0049]

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The polyvinyl alcohol portion of the modified polyvinyl alcohol does not need to have a saponification degree of 100%. In other words, the modified polyvinyl alcohol can include a repeating unit corresponding to vinyl acetate represented by the following formula (V).

[0051]

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In the formula (V), k is 0.01 to 2
0 mol%. Examples of preferred modified polyvinyl alcohol are shown below. I is a repeating unit corresponding to vinyl alcohol represented by the formula (I), and V is a repeating unit corresponding to vinyl acetate represented by the formula (V). The ratio of the repeating unit is mol%.

VA101:-(I) 58- (II-1) 30- (V) 12- VA102:-(I) 48- (II-1) 40- (V) 12- VA103:-(I) 38 -(II-1) 50- (V) 12- VA104 :-( I) 28- (II-1) 60- (V) 12- VA105 :-( I) 48- (II-2) 40- (V ) 12-VA106:-(I) 48- (II-3) 40- (V) 12-VA107:-(I) 48- (II-4) 40- (V) 12-VA108:-(I) 48 -(II-5) 40- (V) 12- VA109:-(I) 28- (II-6) 40- (V) 12- VA110:-(I) 38- (II-7) 50- (V ) 12- VA111:-(I) 58- (II-8) 30- (V) 12-

VA112:-(I) 48- (II-9) 40- (V) 12- VA113:-(I) 48- (II-10) 40- (V) 12- VA114:-(I) 48 -(II-11) 40- (V) 12- VA115 :-( I) 38- (II-12) 50- (V) 12- VA116 :-( I) 38- (II-13) 50- (V ) 12-VA117:-(I) 58- (II-14) 30- (V) 12-VA118:-(I) 38- (II-15) 50- (V) 12-VA119:-(I) 48 -(II-16) 40- (V) 12- VA120 :-( I) 48- (II-17) 40- (V) 12- VA121 :-( I) 48- (II-18) 40- (V ) 12-VA122:-(I) 48- (II-19) 40- (V) 12-

VA123:-(I) 63- (II-20) 25- (V) 12- VA124:-(I) 48- (II-20) 40- (V) 12- VA125:-(I) 58 -(II-21) 30- (V) 12- VA126:-(I) 68- (II-22) 20- (V) 12- VA127:-(I) 58- (II-22) 30- (V ) 12-VA128:-(I) 48- (II-22) 40- (V) 12-VA129:-(I) 58- (II-23) 30- (V) 12-VA130:-(I) 58 -(II-24) 30- (V) 12- VA131:-(I) 68- (II-25) 20- (V) 12- VA132:-(I) 58- (II-25) 30- (V ) 12- VA133:-(I) 48- (II-25) 40- (V) 12-

VA134:-(I) 48- (II-26) 40- (V) 12-VA135:-(I) 58- (II-27) 30- (V) 12-VA136:-(I) 68 -(II-28) 20- (V) 12- VA137:-(I) 58- (II-29) 30- (V) 12- VA138:-(I) 48- (II-30) 40- (V ) 12-VA139:-(I) 58- (II-31) 30- (V) 12-VA140:-(I) 58- (II-32) 30- (V) 12-VA141:-(I) 48 -(II-33) 40- (V) 12- VA142 :-( I) 58- (II-34) 30- (V) 12- VA143 :-( I) 58- (II-35) 30- (V ) 12-

VA201:-(I) 58- (II-1) 25- (III-12) 5- (V) 12- VA202:-(I) 58- (II-1) 25- (III-1) 5- (V) 12-VA203:-(I) 38- (II-1) 40- (III-1) 10- (V) 12-VA204:-(I) 28- (II-1) 55- ( III-1) 5- (V) 12-VA205:-(I) 48- (II-2) 35- (III-1) 5- (V) 12-VA206:-(I) 48- (II-3) ) 35- (III-1) 5- (V) 12-VA207:-(I) 48- (II-4) 35- (III-1) 5- (V) 12-VA208:-(I) 48- (II-5) 35- (III-1) 5- (V) 12-VA209 :-( I) 48- (II-6) 35- (III-1) 5- (V) 12-VA210 :-( I) 38- (II-7) 45- (III- ) 5 - (V) 12- VA211 :-( I) 58- (II-8) 25- (III-1) 5 - (V) 12-

VA212:-(I) 48- (II-9) 35- (III-1) 5- (V) 12- VA213:-(I) 48- (II-10) 35- (III-3) 5- (V) 12-VA214:-(I) 48- (II-11) 35- (III-4) 5- (V) 12-VA215:-(I) 38- (II-12) 47- ( III-8) 3- (V) 12-VA216:-(I) 38- (II-13) 40- (IV-6) 10- (V) 12-VA217:-(I) 58- (II-14) ) 25- (IV-7) 5- (V) 12-VA218 :-( I) 38- (II-15) 45- (III-12) 5- (V) 12-VA219 :-( I) 48- (II-16) 35- (III-12) 5- (V) 12-VA220:-(I) 48- (II-17) 35- (III-12) 5- (V) 12-VA221 :-( I) 48- (II-18) 35- (III-12) 5 (V) 12- VA222 :-( I) 48- (II-19) 35- (III-1) 5 - (V) 12-

VA223:-(I) 58- (II-20) 25- (III-1) 5- (V) 12- VA224:-(I) 38- (II-20) 40- (III-1) 10- (V) 12-VA225:-(I) 58- (II-21) 25- (III-1) 5- (V) 12-VA226:-(I) 63- (II-22) 20- ( III-1) 5- (V) 12-VA227:-(I) 58- (II-22) 25- (III-1) 5- (V) 12-VA228:-(I) 48- (II-22) ) 35- (III-1) 5- (V) 12-VA229:-(I) 58- (II-23) 25- (III-1) 5- (V) 12-VA230:-(I) 58- (II-24) 25- (III-1) 5- (V) 12-VA231 :-( I) 58- (II-25) 25- (III-1) 5- (V) 12-VA232 :-( I) 58- (II-25) 25- (III-12) 5 (V) 12- VA233 :-( I) 48- (II-25) 40- (III-1) 10- (V) 12-

VA234:-(I) 48- (II-26) 35- (III-12) 5- (V) 12- VA235:-(I) 58- (II-27) 25- (III-12) 5- (V) 12-VA236:-(I) 63- (II-28) 20- (III-12) 5- (V) 12-VA237:-(I) 58- (II-29) 25- ( III-1) 5- (V) 12-VA238:-(I) 48- (II-30) 35- (III-2) 5- (V) 12-VA239:-(I) 58- (II-31) ) 25- (III-3) 5- (V) 12-VA240 :-( I) 58- (II-32) 25- (III-4) 5- (V) 12-VA241 :-( I) 48- (II-33) 35- (III-7) 5- (V) 12-VA242 :-( I) 58- (II-34) 25- (III-8) 5- (V) 12-VA243 :-( I) 58- (II-35) 25- (III-9) 5- ( V) 12-

Two or more modified polyvinyl alcohols may be used in combination. The alignment film is obtained by applying a modified polyvinyl alcohol to form a coating layer and rubbing the surface of the coating layer. In the rubbing treatment, the surface of the polymer coating layer is oriented in a certain direction with paper or cloth (usually the longitudinal direction)
And several rubs. The thickness of the alignment film is
The thickness is preferably 0.01 to 5 μm, and more preferably 0.05 to 1 μm. The optically anisotropic layer may be transferred onto a transparent support after the rod-shaped liquid crystalline molecules of the optically anisotropic layer are aligned using an alignment film. The rod-like liquid crystal molecules fixed in the alignment state can maintain the alignment state without the alignment film.

[Optical Anisotropic Layer] The optically anisotropic layer is formed from rod-like liquid crystal molecules. The rod-like liquid crystalline molecules are preferably oriented in a state where the average tilt angle between the major axis direction of the rod-like liquid crystalline molecules and the transparent support surface is less than 5 °. It is preferable to adjust the retardation of the entire optical compensation sheet by providing an optically anisotropic layer. The in-plane retardation (Re) of the entire optical compensation sheet is preferably from 20 to 200 nm, and more preferably from 20 to 100 nm.
Is more preferable, and most preferably 20 to 70 nm. The retardation (Rth) in the thickness direction of the entire optical compensation sheet is preferably from 70 to 500 nm, more preferably from 70 to 400 m, and further preferably from 70 to 300 nm. The in-plane retardation (Re) and the retardation in the thickness direction (Rth) of the optical compensation sheet are respectively defined by the following equations. Re = (nx−ny) × d Rth = [{(nx + ny) / 2} −nz] × d where nx and ny are in-plane refractive indices of the optical compensation sheet, and nz is the thickness of the optical compensation sheet. And d is the thickness of the optical compensatory sheet. By combining an optically anisotropic layer and a transparent support having optical uniaxiality or optical biaxiality, the retardation of the entire optical compensatory sheet can be adjusted. The transparent support having optical uniaxiality or optical biaxiality will be described later.

The rod-like liquid crystalline molecules used in the optically anisotropic layer are preferably fixed in an aligned state. Although the alignment state can be fixed using a polymer binder, it is preferable to fix the alignment state by a polymerization reaction. Depending on the display mode of the liquid crystal cell, the rod-like liquid crystalline molecules may be cholesterically aligned. When the rod-like liquid crystalline molecules are cholesterically aligned, the selective reflection region is preferably outside the visible region. Examples of rod-like liquid crystal molecules include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, and alkoxy-substituted phenylpyrimidines. , Phenyldioxane, tolan and alkenylcyclohexylbenzonitrile are preferably used. The rod-like liquid crystal molecules also include metal complexes. Further, a liquid crystal polymer containing a rod-like liquid crystal molecule in a repeating unit can also be used as the rod-like liquid crystal molecule. In other words, the rod-like liquid crystalline molecules may be bonded to a (liquid crystal) polymer. For rod-like liquid crystal molecules, see Quarterly Chemistry Review Vol. 22, Chapters 4, 7, and 11 of the Chemical Society of Japan (1994), edited by The Chemical Society of Japan, and the Liquid Crystal Device Handbook, edited by the 142nd Committee of the Japan Society for the Promotion of Science There is a description in Chapter 3. The birefringence of the rod-like liquid crystalline molecules is preferably 0.001 to 0.7. The rod-like liquid crystal molecules preferably have a polymerizable group. Examples of the polymerizable group (Q) are shown below.

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The polymerizable group (Q) is an unsaturated polymerizable group (Q1
To Q7), an epoxy group (Q8) or an aziridinyl group (Q9), more preferably an unsaturated polymerizable group, and more preferably an ethylenically unsaturated polymerizable group (Q
1 to Q6) are most preferred. The rod-like liquid crystal molecules preferably have a molecular structure that is substantially symmetric with respect to the minor axis direction. For that purpose, it is preferable to have a polymerizable group at both ends of the rod-shaped molecular structure. Hereinafter, examples of rod-like liquid crystal molecules will be described.

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The optically anisotropic layer is composed of rod-like liquid crystalline molecules or the following polymerizable initiators and optional additives (eg, plasticizer, monomer, surfactant, cellulose ester, 1,3,5
-A liquid crystal composition (coating solution) containing a triazine compound and a chiral agent) is applied on the alignment film.
As the solvent used for preparing the liquid crystal composition, an organic solvent is preferably used. Examples of organic solvents include amides (eg,
N, N-dimethylformamide), sulfoxide (eg,
Dimethyl sulfoxide), heterocyclic compound (eg, pyridine), hydrocarbon (eg, benzene, hexane), alkyl halide (eg, chloroform, dichloromethane), ester (eg, methyl acetate, butyl acetate), ketone (eg, acetone, Methyl ethyl ketone) and ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane). Alkyl halides and ketones are preferred. Two or more organic solvents may be used in combination. The liquid crystal composition can be applied by a known method (eg, a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, a die coating method).

The polymerization reaction of rod-like liquid crystal molecules includes a thermal polymerization reaction using a thermal polymerization initiator and a photopolymerization reaction using a photopolymerization initiator. Photopolymerization reactions are preferred. Examples of photopolymerization initiators include α-carbonyl compounds (U.S. Pat.
No. 661, No. 2367670), acyloin ether (described in US Pat. No. 2,448,828), α-hydrocarbon-substituted aromatic acyloin compound (described in US Pat. No. 2,722,512), polynuclear quinone compound (described in US Pat. Patents 3046127 and 2951758), triarylimidazole dimer and p
-Combination with aminophenyl ketone (US Patent 35
No. 49367), acridine and phenazine compounds (described in JP-A-60-105667, U.S. Pat. No. 4,239,850) and oxadiazole compounds (described in U.S. Pat. No. 4,221,970). The amount of the photopolymerization initiator used is 0.1% of the solid content of the coating solution.
It is preferably from 0.01 to 20% by mass, and more preferably from 0.5 to 5% by mass. Light irradiation for the polymerization of the rod-like liquid crystalline molecules is preferably performed using ultraviolet light. The irradiation energy is 20 mJ / cm ^{2 to} 50 J /
cm ² , preferably 100 to 800 mJ /
cm ² is more preferable. Light irradiation may be performed under heating conditions to promote the photopolymerization reaction. The thickness of the optically anisotropic layer is preferably from 0.1 to 20 μm, more preferably from 0.2 to 15 μm, and most preferably from 0.3 to 10 μm.

[Support] The support is preferably transparent. As the transparent support of the optical compensation sheet, a glass plate or a polymer film, preferably a polymer film is used. The support is transparent when the light transmittance is 8
It means 0% or more. Generally, an optically isotropic polymer film is used as a transparent support. Specifically, the optical isotropy means that the in-plane retardation (Re) is preferably less than 10 nm, and 5n
More preferably, it is less than m. In the case of an optically isotropic transparent support, the retardation in the thickness direction (Rth)
Is also preferably less than 10 nm, more preferably less than 5 nm. The in-plane retardation (Re) of the transparent support and the retardation in the thickness direction (Rt)
h) is each defined by the following equation. Re = (nx−ny) × d Rth = [{(nx + ny) / 2} −nz] × d where nx and ny are in-plane refractive indices of the transparent support, and nz is the thickness of the transparent support. Is the refractive index in the direction, and d is the thickness of the transparent support.

Depending on the type of liquid crystal display mode, an optically anisotropic polymer film may be used as the transparent support. That is, in some cases, the optical anisotropy of the optically anisotropic layer is added to the optical anisotropy of the transparent support to correspond to the optical anisotropy of the liquid crystal cell (optical compensation). In such a case, the transparent support preferably has optical uniaxiality or optical biaxiality. In the case of an optically uniaxial support, even if it is optically positive (the refractive index in the optical axis direction is larger than the refractive index in the direction perpendicular to the optical axis), it is negative (the refractive index in the optical axis direction is (Smaller than the refractive index in the vertical direction).
In the case of an optically biaxial support, the refractive indices nx, ny of the above formula
And nz all have different values (nx ≠ ny ≠ nz). In-plane retardation of optically anisotropic transparent support (R
e) is preferably 0 to 300 nm, more preferably 0 to 200 nm, and 0 to 10 nm.
Most preferably, it is 0 nm. The retardation (Rth) in the thickness direction of the optically anisotropic transparent support is preferably from 10 to 1,000 nm, and from 50 to 400 n.
m, more preferably 100 to 300 nm.

The material for forming the transparent support is determined depending on whether it is an optically isotropic support or an optically anisotropic support. In the case of an optically isotropic support, glass or cellulose ester is generally used. In the case of an optically anisotropic support, a synthetic polymer (eg, polycarbonate, polysulfone, polyethersulfone, polyacrylate, polymethacrylate, norbornene resin) is generally used. However, the use of (1) the use of a retardation increasing agent (a birefringence increasing agent), (2) a decrease in the degree of acetylation of cellulose acetate, or (3) a cooling dissolution method described in EP0911656A2. By producing a film, an optically anisotropic (high retardation) cellulose ester film can also be produced. The transparent support made of a polymer film is preferably formed by a solvent casting method.

In order to obtain an optically anisotropic transparent support, it is preferable to carry out a stretching treatment on the polymer film.
When an optically uniaxial support is produced, ordinary uniaxial stretching or biaxial stretching may be performed. When producing an optically biaxial support, it is preferable to carry out an unbalanced biaxial stretching treatment. In unbalanced biaxial stretching, a polymer film is stretched in a certain direction at a certain magnification (for example, 3
To 100%, preferably 5 to 30%), and a higher magnification (eg, 6 to 200%) in the direction perpendicular thereto.
%, Preferably 10 to 90%). The bidirectional stretching may be performed simultaneously. It is preferable that the stretching direction (the direction of higher stretching ratio in unbalanced biaxial stretching) and the in-plane slow axis of the stretched film be substantially the same. The angle between the stretching direction and the slow axis is preferably less than 10 °, more preferably less than 5 °, and most preferably less than 3 °. When a transparent support having optical uniaxiality or optical biaxiality is used, the average direction of a line obtained by projecting the major axis direction of the rod-like liquid crystalline molecules of the optically anisotropic layer onto the transparent support surface. Are preferably arranged so as to be substantially parallel or orthogonal to the in-plane slow axis of the transparent support.

The thickness of the transparent support is 10 to 500 μm
Is more preferable, and more preferably 50 to 200 μm. In order to improve the adhesion between the transparent support and the layer provided thereon (adhesion layer, alignment film or optically anisotropic layer), the transparent support is subjected to a surface treatment (eg, glow discharge treatment, corona discharge treatment, ultraviolet light). (UV) treatment, flame treatment). An ultraviolet absorber may be added to the transparent support. Adhesion layer (undercoat layer) on transparent support
May be provided. For the adhesion layer, see JP-A-7-333.
No. 433. The thickness of the adhesion layer is preferably from 0.1 to 2 μm, more preferably from 0.2 to 1 μm.

[Polarizing Film] As the polarizing film, an iodine-based polarizing film,
There are a dye-based polarizing film using a dichroic dye and a polyene-based polarizing film. The iodine-based polarizing film and the dye-based polarizing film are generally manufactured using a polyvinyl alcohol-based film. The transmission axis of the polarizing film corresponds to a direction perpendicular to the stretching direction of the film. The transmission axis of the polarizing film is disposed so as to be substantially parallel to the average direction (slow axis) of a line obtained by projecting the major axis direction of the rod-shaped liquid crystal molecules onto the surface of the transparent support.

[Transparent Protective Film] As the transparent protective film, a transparent polymer film is used. That the protective film is transparent means that the light transmittance is 80% or more. As the transparent protective film, a cellulose ester film, preferably a triacetyl cellulose film, is generally used. The cellulose ester film is preferably formed by a solvent casting method. The thickness of the transparent protective film is preferably 20 to 500 μm,
More preferably, it is 0 to 200 μm.

[Liquid Crystal Display Device] The present invention can be applied to liquid crystal cells of various display modes. As described above, the optical compensation sheet using liquid crystal molecules is formed of a TN (Twisted Nemati).
c), IPS (In-Plane Switching), FLC (Ferroel
ectric Liquid Crystal), OCB (Optically Compensa)
tory Bend), STN (Supper Twisted Nematic), V
A (Vertically Aligned), ECB (Electrically Cont
rolled Birefringence) and HAN (Hybrid Aligne)
dNematic) mode liquid crystal cells have already been proposed. The optical compensatory sheet and the polarizing plate of the present invention are preferably arranged such that the slow axis of the optical compensatory sheet and the transmission axis of the polarizing film are substantially parallel to each other, for example, a TN mode or a VA mode. It is preferable to use it for a liquid crystal display device. The present invention is particularly effective in a VA mode liquid crystal display device. The VA mode liquid crystal cell includes (1) a VA mode liquid crystal cell in a narrow sense in which rod-like liquid crystal molecules are aligned substantially vertically when no voltage is applied and substantially horizontally when voltage is applied. 176
625), and (2) a liquid crystal cell (SID97, Digest of tech. Papers) in which the VA mode is multi-domain (in the MVA mode) in order to enlarge the viewing angle.
(Proceedings) 28 (1997) 845), (3) A mode in which rod-like liquid crystalline molecules are substantially vertically aligned when no voltage is applied, and twisted multi-domain alignment is performed when a voltage is applied (n
-ASM mode) liquid crystal cell (described in Proceedings 58-59 (1998) of Japanese Liquid Crystal Symposium) and (4) SURVA
Includes IVAL mode liquid crystal cells (presented at LCD International 98).

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[Example 1] (Formation of alignment film) Modified polyvinyl alcohol (VA23)
1) was dissolved in a mixed solvent of N-methylpyrrolidone / methylethylketone (mass ratio = 1/4) to prepare a 4% by mass solution. This solution was applied to a thickness of 1 μm on a glass support using a bar coater. 120 ° C for coating layer
For 5 minutes and dried. The surface of the coating layer was rubbed to form an alignment film.

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(Formation of Optically Anisotropic Layer) On the alignment film,
Using a bar coater, a coating solution having the following composition was 0.7 μm
To a thickness of

<< Composition of Optically Anisotropic Layer Coating Solution >>棒 100 parts by mass of rod-like liquid crystalline molecule (N71) Photopolymerization initiator (Irgacure 907, manufactured by Nippon Ciba Geigy Co., Ltd.) 3 parts by mass Photopolymerization sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 1 part by mass Methyl ethyl ketone 400 parts by mass ──────────────────────

The coating layer was heated at 100 ° C. for 1 minute to align the rod-like liquid crystalline molecules. At that temperature, ultraviolet rays were irradiated for 4 seconds to polymerize the rod-like liquid crystalline molecules, and the alignment state was fixed. Thus, an optically anisotropic layer was formed to produce an optical compensation sheet. Observation of the orientation of the optically anisotropic layer and the director (long axis direction) of the rod-like liquid crystal molecules using a polarizing microscope revealed that the rod-like liquid crystal molecules were oriented so that the long axis direction was perpendicular to the rubbing direction. I was Further, the retardation in the thickness direction (R
When th) was measured, it was 105 nm.

Example 2 An optical compensatory sheet was prepared and evaluated in the same manner as in Example 1 except that the same amount of the modified polyvinyl alcohol (VA232) was used instead of the modified polyvinyl alcohol (VA231). Observation of the orientation of the optically anisotropic layer and the director (long axis direction) of the rod-like liquid crystal molecules using a polarizing microscope revealed that the rod-like liquid crystal molecules were oriented so that the long axis direction was perpendicular to the rubbing direction. I was When the retardation (Rth) in the thickness direction was measured using an ellipsometer, the retardation was 105 n.
m.

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Example 3 An optical compensatory sheet was prepared and evaluated in the same manner as in Example 1 except that the same amount of the modified polyvinyl alcohol (VA205) was used instead of the modified polyvinyl alcohol (VA231). Observation of the orientation of the optically anisotropic layer and the director (long axis direction) of the rod-like liquid crystal molecules using a polarizing microscope revealed that the rod-like liquid crystal molecules were oriented so that the long axis direction was perpendicular to the rubbing direction. I was When the retardation (Rth) in the thickness direction was measured using an ellipsometer, the retardation was 105 n.
m.

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[Example 4] (Preparation of transparent support) 4.0% by mass of the following birefringence increasing agent was added to cellulose triacetate, and the thickness was 100 µm.
m of cellulose triacetate film was prepared. The obtained cellulose triacetate film,
Used as a transparent support.

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(Formation of Alignment Film) Modified polyvinyl alcohol (VA231) was dissolved in a mixed solvent of N-methylpyrrolidone / methylethylketone (mass ratio = 1/4).
A 4% by weight solution was prepared. This solution was continuously applied onto a roll-shaped transparent support while transporting it using a bar coater. The coating layer was heated at 120 ° C. for 5 minutes and dried to form a layer having a thickness of 1 μm. While transporting the roll-shaped transparent support provided with the coating layer, in the longitudinal direction (transport direction)
The surface of the coating layer was continuously rubbed to form an alignment film.

(Formation of Optically Anisotropic Layer) On the alignment film,
A coating solution having the following composition was continuously applied using a bar coater.

<< Composition of Optically Anisotropic Layer Coating Solution >>棒 100 parts by mass of rod-like liquid crystalline molecule (N71) Photopolymerization initiator (Irgacure 907, manufactured by Nippon Ciba Geigy Co., Ltd.) 3 parts by mass Photopolymerization sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 1 part by mass Methyl ethyl ketone 400 parts by mass ──────────────────────

The coating layer was heated at 100 ° C. for 1 minute to align the rod-like liquid crystalline molecules. 400m for 4 seconds at that temperature
The rod-like liquid crystalline molecules were polymerized by irradiating ultraviolet rays of j / cm ² to fix the alignment state. Thus, an optically anisotropic layer was formed to produce an optical compensation sheet. The rod-like liquid crystal molecules were oriented such that the major axis direction was orthogonal to the longitudinal direction of the optical compensation sheet. The ellipsometer (M-1)
50, manufactured by JASCO Corporation, the retardation of the entire optical compensation sheet at a wavelength of 550 nm was measured. The in-plane retardation (Re) was 25 nm and the retardation in the thickness direction (Rth) was 105 nm. .

(Preparation of Polarizing Plate) A roll-shaped polyvinyl alcohol film having a thickness of 80 μm was continuously stretched 5 times in an aqueous iodine solution and dried to obtain a polarizing film. On one surface of the polarizing film, a saponified rolled cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was provided, and on the other surface, a transparent support of a saponified rolled optical compensation sheet was prepared. By continuously bonding, a polarizing plate was produced. The slow axis of the optical compensation sheet (the major axis direction of the rod-like liquid crystal molecules) was parallel to the transmission axis of the polarizing film.

(Preparation of Liquid Crystal Display) A commercially available MVA liquid crystal display (VL-1530S, manufactured by Fujitsu Ltd.) was used.
The polarizing plate and the optical compensatory sheet on the observer side and the backlight side were deleted, and instead, two sheets of polarizing plates produced were stuck. The viewing angle of the manufactured MVA liquid crystal display device was measured with a viewing angle measuring device (EZContrast 160D, manufactured by ELDIM). As a result, the viewing angle in the transmission axis direction of the polarizing film and the viewing angle in the direction at 45 ° from the transmission axis direction exceeded 80 °.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a basic configuration of a transmission type liquid crystal display device.

FIG. 2 is a schematic diagram showing a basic configuration of a reflection type liquid crystal display device.

FIG. 3 is a schematic view showing a step of bonding a roll-shaped polarizing element and a roll-shaped optical compensation sheet.

[Explanation of symbols]

 BL Backlight LD Longitudinal direction RP Reflector SA Slow axis of optically anisotropic layer TA Transmission axis of polarizing film 1, 1a, 1b, 1c Transparent protective film 2, 2a, 2b Polarizing film 3, 3a, 3b Transparent support Body 4, 4a, 4b Optically anisotropic layer 5a Lower substrate of liquid crystal cell 5b Upper substrate of liquid crystal cell 6 Rod-like liquid crystalline molecular layer

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] March 21, 2001 (2001.3.2)
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

Embedded image Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%].

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 3

[Correction method] Change

[Correction contents]

Embedded image Wherein R ² is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; L ¹ is a single bond or a divalent linking group; and Q is a polymerizable group. And 1 is 0.1 to 20 mol%].

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] Claim 4

[Correction method] Change

[Correction contents]

Embedded image Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%].

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] Claim 9

[Correction method] Change

[Correction contents]

Embedded image Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%].

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] Claim 10

[Correction method] Change

[Correction contents]

Embedded image Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%].

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] Claim 11

[Correction method] Change

[Correction contents]

Embedded image

Embedded image [Wherein, R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; R ² is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group, or a heterocyclic group; L ¹ is a single bond or a divalent linking group; Q is a polymerizable group; M is from 10 to 95 mol%; and
n is 5 to 90 mol%].

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0009

[Correction method] Change

[Correction contents]

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[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction contents]

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[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

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──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08F 216/06 C08F 216/06 4J100 224/00 224/00 226/00 226/00 299/00 299/00 G02F 1/1335 510 G02F 1/1335 510 1/13363 1/13363 1/1337 1/1337 F term (reference) 2H049 BA02 BA06 BA27 BA42 BB03 BB43 BB49 BB51 BC03 BC04 BC22 2H090 HB13Y HC05 LA06 LA09 MA06 MB01 2H091 FA08X FA08Z FB02 GA06 GA16 LA12 4F100 AG00 AK02B AK03B AK21B AK69B AL01B AL06B AS00B AT00A BA02 EG002 EH112 EH462 EJ862 GB41 JA11B JN10 4J027 AA01 AA02 AA05 AA06 AA08 CB10 CC02 CC04 CD08 4J100 AA15Q AA20Q AB00Q AB02Q AB03Q AB04Q AB07Q AB08Q AB09Q AB10Q AC00Q AC59Q AD02P AH02R AH07R AH40R AL74Q AL74R AQ01Q AQ06Q AQ11Q AQ12Q AQ15Q AQ19Q AQ25Q AQ28Q AS15Q BA02Q BA02R BA03Q BA05Q BA11Q BA13Q BA15Q BA15R BA16Q BA29Q BA32Q BA38Q BA 38R BA56Q BB01Q BB01R BB03Q BB03R BB05Q BB05R BB07Q BB07R BC43Q BC43R BC54Q BC54R BC65R CA04 CA05 HA35 JA01 JA32

Claims (11)

[Claims] 1. A liquid crystal alignment film provided on a support, comprising a modified polyvinyl alcohol containing a repeating unit represented by the following formula (I) and a repeating unit represented by the following formula (II): Liquid crystal alignment film characterized by: Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%]. 2. The liquid crystal alignment film according to claim 1, wherein the modified polyvinyl alcohol further has a polymerizable group. 3. The liquid crystal alignment film according to claim 1, wherein the modified polyvinyl alcohol further contains a repeating unit represented by the following formula (III). Embedded image Wherein R ² is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; L ¹ is a single bond or a divalent linking group; and Q is a polymerizable group. And 1 is 0.1 to 20 mol%]. 4. A coating layer is provided on a support by applying a modified polyvinyl alcohol containing a repeating unit represented by the following formula (I) and a repeating unit represented by the following formula (II); Rubbing the surface of to form an alignment film;
Then, a coating liquid containing rod-like liquid crystal molecules is applied on the alignment film and dried, so that the average direction of the line obtained by projecting the major axis direction of the rod-like liquid crystal molecules on the transparent support surface and the alignment film Method for aligning rod-like liquid crystalline molecules so that the rubbing direction is substantially orthogonal to: Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%]. 5. The rod-shaped liquid crystal molecule according to claim 4, wherein the rod-shaped liquid crystal molecule has a polymerizable group, and after the rod-shaped liquid crystal molecule is aligned, the rod-shaped liquid crystal molecule is polymerized to fix the alignment state. A method of orienting. 6. The support has a roll shape, and the average direction of a line obtained by projecting the major axis direction of the rod-shaped liquid crystalline molecules onto the support surface is substantially perpendicular to the longitudinal direction of the support. The method for aligning rod-like liquid crystalline molecules according to claim 4. 7. The method for aligning rod-like liquid crystalline molecules according to claim 4, wherein the support is in a roll shape, and the rubbing direction of the alignment film is substantially parallel to the longitudinal direction of the support. 8. The rod-shaped liquid crystal molecules according to claim 4, wherein the rod-shaped liquid crystal molecules are aligned in a state where the average inclination angle between the major axis direction of the rod-shaped liquid crystal molecules and the support surface is less than 5 °. Method. 9. A roll-shaped optical compensation sheet having a transparent support, an alignment film and an optically anisotropic layer formed of rod-like liquid crystalline molecules in this order, wherein the alignment film is represented by the following formula (I): The average direction and orientation of lines obtained by projecting the major axis direction of rod-like liquid crystalline molecules onto the transparent support surface, comprising a modified polyvinyl alcohol containing a repeating unit represented by the following formula and a repeating unit represented by the following formula (II): An optical compensatory sheet characterized in that rod-like liquid crystalline molecules are oriented so that the rubbing direction of the film is substantially perpendicular to the film. Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%]. 10. A roll-shaped polarizing plate having an optically anisotropic layer formed from rod-shaped liquid crystalline molecules, an alignment film, a transparent support, a polarizing film and a transparent protective film, wherein the alignment film has the following formula: It is composed of a modified polyvinyl alcohol containing a repeating unit represented by the following formula (II) and a repeating unit represented by the following formula (II), and the average tilt angle between the major axis direction of the rod-like liquid crystal molecules and the transparent support surface is The rod-like liquid crystal molecules are oriented in a state of less than 5 °, and the average direction of the line obtained by projecting the major axis direction of the rod-like liquid crystal molecules on the transparent support surface and the longitudinal direction of the polarizing plate are substantially orthogonal. And the transmission axis of the polarizing film and the average direction of a line obtained by projecting the major axis direction of the rod-like liquid crystalline molecules onto the surface of the transparent support are substantially parallel to each other. Formula 5 Wherein R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group or a heterocyclic group; 9
5 mol%; and n is 5 to 90 mol%]. 11. A modified polyvinyl alcohol containing a repeating unit represented by the following formula (I), a repeating unit represented by the following formula (II) and a repeating unit represented by the following formula (III): Embedded image [Wherein, R ¹ is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; R ² is a hydrogen atom, a halogen atom or an alkyl group having 1 to 6 carbon atoms; Cy is an aliphatic ring group, an aromatic group, or a heterocyclic group; L ¹ is a single bond or a divalent linking group; Q is a polymerizable group; M is from 10 to 95 mol%; and
n is 5 to 90 mol%].