JP2006124639A - Polymer film, liquid crystal alignment layer, retardation plate and liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a new polymer film that quickly orients a liquid crystal compound in a reduced state of defects such as schlieren defect, etc., in the case of use as a liquid crystal alignment layer. <P>SOLUTION: The polymer film comprises a compound represented by general formula (I) (R<SP>1</SP>and R<SP>2</SP>are each independently a hydrogen atom or a substituted or nonsubstituted aliphatic hydrocarbon group, aryl group or a heteroaryl group; X is a bifunctional connecting group or a substituted or nonsubstituted aliphatic hydrocarbon group, aryl group or heteroaryl group; Z is a polymerizable group-containing substituent group; R<SP>1</SP>and R<SP>2</SP>may be bonded through an alkylene connecting group, an aryl connecting group or a connecting group composed of a combination of these connecting groups; Z may be not contained in the molecule) and a polymer. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a polymer film used for a liquid crystal alignment film or the like. The present invention also relates to a retardation plate in which a liquid crystal alignment film polymer and a liquid crystalline compound in an optically anisotropic layer are in close contact by an interaction at an interface, and a liquid crystal display device having the retardation plate. The present invention also provides a retardation film that can be suitably used for an in-plane switching mode liquid crystal display device that performs display by applying a horizontal electric field to liquid crystal molecules that are aligned in the horizontal direction. The present invention relates to a liquid crystal display device.

  Conventionally, boric acid-crosslinked polyvinyl alcohol has been applied to a liquid crystal alignment film or a polarizing film. A retardation plate having an optically anisotropic layer formed by using such polyvinyl alcohol as a liquid crystal alignment film has also been proposed. The phase difference plate is used in various liquid crystal display devices for eliminating image coloring and widening the viewing angle. Conventionally, a stretched birefringent film has been used as a retardation plate, but in recent years, a retardation plate having an optically anisotropic layer made of discotic liquid crystalline molecules on a transparent support instead of a stretched birefringent film. It has been proposed to use For this optically anisotropic layer, a composition containing discotic liquid crystal molecules is usually applied on the alignment film, heated to a temperature higher than the alignment temperature to align the discotic liquid crystalline molecules, and the alignment state is fixed. It is formed by doing.

Various alignment films that define the alignment direction of the discotic liquid crystal compound are known. Inorganic oblique vapor deposition films using metal oxides or fluorides such as SiO, TiO ₂ , and MgF ₂ as vapor deposition materials, And a thin film in which isomerization is caused by light and molecules are uniformly arranged with directionality, such as an LB film made of an azobenzene derivative. Among them, a polymer layer whose surface is rubbed is preferable from the viewpoint of productivity. Various polyimides are used as the polymer for the alignment film. In addition, the polyamide described in Patent Document 1, the polyvinyl alcohol described in Patent Document 2, 3, 4 or 5, etc., polystyrene, polyvinylcarbazole and the like are also used.

Among them, the optical compensation sheet described in Patent Document 3 using a modified polyvinyl alcohol in which a part of the hydroxyl group is substituted with a crosslinkable group as an alignment film greatly increases the viewing angle in all directions. is there. This optical compensation sheet comprises a transparent support, an alignment film made of polyvinyl alcohol subjected to rubbing treatment provided thereon, and an optically anisotropic layer of a discotic liquid crystalline compound formed on the alignment film. Have. This optical compensation sheet contributes to the expansion of the viewing angle by utilizing the optical anisotropy expressed by the orientation of the discotic liquid crystalline compound. Furthermore, since a crosslinkable group is introduced into the alignment film, the polymer of the alignment film and the optically anisotropic layer are chemically bonded via the interface between these layers, so that it can be stored for a long time. Even when used, the optically anisotropic layer does not peel off.
However, even if the alignment film described in Patent Document 3 is used, it is difficult to say that uniform alignment without alignment defects is obtained, and there is still a problem that a long aging time is required to align the liquid crystal compound. .

  By the way, as a liquid crystal display device, a so-called TN mode in which a liquid crystal layer in which nematic liquid crystal is twisted and arranged between two orthogonal polarizing plates is sandwiched and an electric field is applied in a direction perpendicular to the substrate is widely used. Yes. In this method, since liquid crystal molecules rise with respect to the substrate during black display (liquid crystal molecules are aligned perpendicular to the substrate), birefringence due to the liquid crystal molecules occurs when viewed from an oblique direction, and light leakage occurs. In order to solve this problem, a system in which a liquid crystal cell is optically compensated by using a film in which liquid crystal molecules are hybrid-aligned and this light leakage is prevented has been put into practical use. However, even if liquid crystal molecules are used, it is very difficult to completely optically compensate the liquid crystal cell without any problem, resulting in a problem that gradation reversal in the lower direction of the screen cannot be suppressed.

  In order to solve such a problem, a liquid crystal display device using a so-called in-plane switching (IPS) mode in which a lateral electric field is applied to the liquid crystal, or a liquid crystal having a negative dielectric anisotropy is vertically aligned and formed in the panel. A vertical alignment (VA) mode in which alignment is divided by protrusions and slit electrodes has been proposed and put into practical use. In recent years, these panels have been developed not only for monitor applications but also for TV applications, and screen brightness has been greatly improved accordingly. For this reason, a slight light leakage in the diagonally oblique incident direction during black display, which has not been considered as a problem in these operation modes, has become apparent as a cause of a decrease in display quality.

As one means for improving the color tone and the viewing angle of black display, the arrangement of an optical compensation material having birefringence characteristics between the liquid crystal layer and the polarizing plate is also studied in the IPS mode.
For example, by arranging a birefringent medium with optical axes orthogonal to each other to compensate for increase / decrease in retardation of the liquid crystal layer during tilting, the white display or halftone display is obliquely arranged between the substrate and the polarizing plate. It is disclosed that coloring can be improved when viewing directly from (see, for example, Patent Document 6). In addition, a method using an optical compensation film made of a styrene polymer having a negative intrinsic birefringence or a discotic liquid crystalline compound (see, for example, Patent Documents 7 to 9), or an optical axis having a positive birefringence as an optical compensation film. Is a method of combining a film in the plane of the film with a film having a positive birefringence and an optical axis in the normal direction of the film (see, for example, Patent Document 10), and the retardation is biaxial with a half wavelength A method of using an optical compensation sheet (for example, see Patent Document 11), a method of using a film having negative retardation as a protective film of a polarizing plate, and providing an optical compensation layer having positive retardation on this surface (for example, Patent Document 12) has been proposed.

  On the other hand, a method of achieving optical compensation of IPS by combining a retardation film having a positive birefringence and an optical axis in the normal direction has been studied. In order to realize such a retardation film, a liquid crystal material is used. There is known a method of vertically aligning and fixing the alignment state (see, for example, Patent Documents 13 to 15).

  As a method for vertically aligning the rod-like liquid crystalline compound, a method using a vertical alignment film as the alignment film, or a vertical alignment agent (for example, a quaternary ammonium-substituted silane coupling agent) is formed on the substrate. In addition, a method for forming a layer of a liquid crystal compound has been proposed (for example, Non-Patent Documents 1 and 2). However, in recent years, demands for display characteristics of monitors have become stricter, and anisotropic materials fixed by a conventionally known vertical alignment method do not have sufficient micro-uniformity, and improvements have been demanded. In addition, using a special alignment film or the like is not suitable for manufacturing on an industrial level.

Japanese Patent Laid-Open No. 3-9326 JP-A-3-291601 JP 9-152509 A Japanese Patent Laid-Open No. 14-268068 Japanese Patent Laid-Open No. 14-350859 Japanese Patent Laid-Open No. 9-80424 Japanese Patent Laid-Open No. 10-54982 JP-A-11-202323 Japanese Patent Laid-Open No. 9-292522 JP 11-133408 A JP-A-11-305217 JP-A-10-307291 Special Table 2000-514202 Japanese Patent Laid-Open No. 10-319408 JP-A-6-331826 Mitsuharu Okano et al., “Liquid Crystal”, Application, Bafukan, 1985, 61 pages Shohei Naemura, Appl. Phys. Lett. 33, No. 1, 1978, 1-3

The problem to be solved by the present invention is to provide a novel polymer film that, when used as a liquid crystal alignment film, can rapidly align a liquid crystal compound with few defects such as schlieren defects. That is. Another object of the present invention is to provide a retardation plate that has excellent durability and contributes to an increase in the viewing angle of the liquid crystal display device, and a liquid crystal display device having the retardation plate.
Another object of the present invention is to provide a retardation film in which molecules of a rod-like liquid crystal compound are vertically aligned uniformly without defects, and further, with a simple configuration, not only display quality but also a field of view. It is to provide a liquid crystal display device (in particular, an IPS liquid crystal display device) with improved corners.

The above problems have been achieved by the following means.
[1] A polymer film comprising a composition containing a compound represented by the following general formula (I) and a polymer:

一般式（Ｉ）中、Ｒ¹及びＲ²はそれぞれ独立に、水素原子、或いは、置換もしくは無置換の、脂肪族炭化水素基、アリール基又はヘテロアリール基を表し、Ｘは二価の連結基または置換もしくは無置換の、脂肪族炭化水素基、アリール基又はヘテロ環基を表し、Ｚは重合性基を有する置換基を表し、また、Ｒ¹とＲ²は、アルキレン連結基、アリール連結基、又はこれらの組み合わせからなる連結基を介して連結してもよく、分子中にＺを有しなくてもよい
［２］ 前記一般式（Ｉ）中、Ｒ¹及びＲ²がそれぞれ水素原子を表し、Ｚが下記一般式（II）で表される基、又はオキシラニル部分もしくはオキセタン部分を有する基である［１］の高分子膜：

In general formula (I), R ¹ and R ² each independently represent a hydrogen atom or a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heteroaryl group, and X represents a divalent linking group. Or a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heterocyclic group, Z represents a substituent having a polymerizable group, and R ¹ and R ² represent an alkylene linking group or an aryl linking group. Or may be linked via a linking group consisting of a combination thereof, and may not have Z in the molecule. [2] In the general formula (I), R ¹ and R ² each represent a hydrogen atom. The polymer film of [1], wherein Z is a group represented by the following general formula (II), or a group having an oxiranyl moiety or an oxetane moiety:

一般式（II）中、Ｒ³は水素原子又はメチル基であり、Ｌは、−Ｏ−、−ＣＯ−、−ＮＨ−、−ＣＯ−ＮＨ−、−ＣＯＯ−、−Ｏ−ＣＯＯ−、アルキレン基、アリーレン基、ヘテロ環基、及びそれらの組み合わせから選ばれる二価の連結基である。
［３］ 前記一般式（Ｉ）で表される化合物と、ポリマーとが化学的に結合している［１］又は［２］の高分子膜。
［４］ 前記ポリマーが、ポリビニルアルコールである［１］〜［３］のいずれかの高分子膜。

In the general formula (II), R ³ is a hydrogen atom or a methyl group, and L is —O—, —CO—, —NH—, —CO—NH—, —COO—, —O—COO—, alkylene. A divalent linking group selected from a group, an arylene group, a heterocyclic group, and combinations thereof.
[3] The polymer film according to [1] or [2], wherein the compound represented by the general formula (I) and the polymer are chemically bonded.
[4] The polymer film according to any one of [1] to [3], wherein the polymer is polyvinyl alcohol.

[5] A polymer film comprising a polymer represented by the following general formula (III):

一般式（III）中、ｌ＋ｍ＋ｎ＝１００の条件にて、ｌは１０〜９９．９モル％、ｍは０〜７０モル％、ｎは０．０１〜８０モル％であり、Ｘ及びＺは一般式（Ｉ）中のＸ及びＺと同義である。

In the general formula (III), l is 10 to 99.9 mol%, m is 0 to 70 mol%, n is 0.01 to 80 mol%, and X and Z are general in the condition of l + m + n = 100 It is synonymous with X and Z in Formula (I).

[6] A liquid crystal alignment film comprising the polymer film according to any one of [1] to [5].
[7] A retardation plate comprising a transparent support, the liquid crystal alignment film according to claim 6, and an optically anisotropic layer containing at least one liquid crystalline compound.
[8] A liquid crystal display device having the retardation plate of [7].

In the present specification, the retardation value in the in-plane direction (Re; hereinafter simply referred to as “Re”) and the retardation value in the film thickness direction (Rth; hereinafter referred to simply as “Rth”). .) Is calculated based on the following.
Re (λ) and Rth (λ) respectively represent in-plane direction retardation and thickness direction retardation at wavelength λ.
The Re (λ) is measured by making light having a wavelength of λ nm incident in the normal direction of the film in “KOBRA 21ADH” (manufactured by Oji Scientific Instruments). Rth (λ) is a wavelength of λ nm from the direction inclined by + 40 ° with respect to the normal direction of the film, with Re (λ) and the slow axis (determined by KOBRA 21ADH) as the tilt axis (rotation axis). Retardation value measured by incidence of light and retardation value measured by incidence of light having a wavelength of λ nm from a direction inclined by -40 ° with respect to the film normal direction with the in-plane slow axis as the tilt axis Based on the retardation values measured in a total of three directions, the above-mentioned “KOBRA 21ADH” can be used. At this time, it is necessary to input an assumed value of average refractive index and a film thickness. “KOBRA 21ADH” can calculate nx, ny, and nz in addition to Rth (λ). Here, nx is the refractive index in the slow axis (x) direction in the film plane, ny is the refractive index in the fast axis (y) direction in the film plane, and nz is the film thickness direction (film Refractive index in the direction perpendicular to the surface.

  As for the above “average refractive index”, 1.48 is used for cellulose acetate, but values of polymer films for typical optical applications other than cellulose acetate include cycloolefin polymer (1.52), polycarbonate (1.59). ), Polymethyl methacrylate (1.49), polystyrene (1.59), and the like. As the average refractive index value of other existing polymer materials, a polymer handbook (John Wiley & Sons, Inc.) or a catalog value of a polymer film can be used. In addition, in the case of a material whose average refractive index is unknown, it can be measured using an Abbe refractometer. Further, Nz = (nx−nz) / (nx−ny) is further calculated from the calculated nx, ny, and nz.

  Further, in the present specification, “parallel” and “orthogonal” mean that the angle is within a range of strictly less than ± 10 °. In this range, an error from a strict angle is preferably less than ± 5 °, and more preferably less than ± 2 °. Further, “substantially vertical” means within a range of less than ± 20 ° from a strict vertical angle. In this range, an error from a strict angle is preferably less than ± 15 °, and more preferably less than ± 10 °. The “slow axis direction” means a direction in which the refractive index is maximized. Further, the measurement wavelength of the refractive index is a value at λ = 550 nm in the visible light region unless otherwise specified.

  In this specification, unless otherwise specified, the term “polarizing plate” is cut into a size to be incorporated into a long polarizing plate and a liquid crystal device (in this specification, “cutting” includes “punching” and “cutting out”. It is used in the meaning including both of the polarizing plates. In this specification, “polarizing film” and “polarizing plate” are distinguished from each other, but “polarizing plate” means a laminate having a transparent protective film for protecting the polarizing film on at least one surface of the “polarizing film”. It shall be.

In the present invention, a polymer film is formed from a boronic acid compound represented by the formula (I) and a polymer. Since the boronic acid compound can be chemically bonded to the compound in the layer formed on the surface of the polymer film of the present invention, peeling or the like hardly occurs even when used and stored for a long time. For example, when polyvinyl alcohol is used as the polymer, a polymerizable boronic acid compound can be bonded to the main chain of polyvinyl alcohol via an ether bond or the like, and the polymer film made of the polyvinyl alcohol derivative is a liquid crystal It is useful as an alignment film. By using such a polymer film made of a polyvinyl alcohol derivative as the liquid crystal alignment film, the liquid crystal compound can be rapidly aligned with few defects such as schlieren defects. Therefore, according to the present invention, it is possible to provide a retardation plate that has excellent durability and contributes to an increase in the viewing angle of the liquid crystal display device, and a liquid crystal display device having the retardation plate.
In addition, according to the present invention, it is possible to provide a retardation film in which a rod-like liquid crystalline compound is vertically aligned uniformly without defects or with few defects. Furthermore, according to the present invention, it is possible to provide a liquid crystal display device with a simple configuration and an improved viewing angle as well as display quality.

BEST MODE FOR CARRYING OUT THE INVENTION

  The contents of the present invention will be reported in detail below. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.

Hereinafter, the present invention will be described in detail.
[Polymer film]
The present invention relates to a polymer film comprising a composition containing a compound represented by the following general formula (I) and a polymer. The compound of the general formula (I) and the polymer are preferably chemically bonded.

In general formula (I), R ¹ and R ² each independently represent a hydrogen atom or a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heteroaryl group, and X represents a divalent linking group. Or a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heterocyclic group, Z represents a substituent having a polymerizable group, and R ¹ and R ² represent an alkylene linking group or an aryl linking group. Or may be linked via a linking group consisting of a combination thereof, and Z may not be present in the molecule.

In general formula (I), the substituted or unsubstituted aliphatic hydrocarbon group represented by R ¹ and R ² includes a substituted or unsubstituted alkyl group, an alkenyl group, and an alkynyl group.
Specific examples of the alkyl group include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, hexadecyl, Octadecyl group, eicosyl group, isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-methylhexyl group, cyclopentyl group, cyclohexyl group, 1- Examples include a linear, branched, or cyclic alkyl group such as an adamantyl group and a 2-norbornyl group. Specific examples of the alkenyl group include linear, branched, such as vinyl group, 1-propenyl group, 1-butenyl group, 1-methyl-1-propenyl group, 1-cyclopentenyl group and 1-cyclohexenyl group. Or a cyclic alkenyl group. Specific examples of the alkynyl group include ethynyl group, 1-propynyl group, 1-butynyl group, 1-octynyl group and the like. Specific examples of the aryl group include those in which 1 to 4 benzene rings form a condensed ring, and those in which a benzene ring and an unsaturated five-membered ring form a condensed ring. Specific examples include Examples include a phenyl group, a naphthyl group, an anthryl group, a phenanthryl group, an indenyl group, an acenaphthenyl group, a fluorenyl group, and a pyrenyl group.

Specific examples of the substituted or unsubstituted aryl group represented by R ¹ and R ² include a phenyl group and a naphthyl group. Examples of the substituted or unsubstituted heteroaryl group represented by each of R ¹ and R ² include hydrogen on a heteroaromatic ring containing one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom. Including those in which one atom is removed to form a heteroaryl group. Specific examples of the heterocyclic ring contained in the heteroaryl group are the same as the specific examples of the heterocyclic ring contained in the heteroarylene group represented by X described later.

R ¹ and R ^{2 in} formula (I) are preferably each independently a hydrogen atom, an aliphatic hydrocarbon group (the number of carbon atoms is preferably 1 or 2, and more preferably 1), or R ¹ and R ² Are bonded to form a ring (a 5-membered ring is most preferable), and a hydrogen atom is most preferable.

In general formula (I), X represents a divalent linking group or a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heterocyclic group. When Z is present, X represents a divalent linking group.
Examples of the linking group include a single bond, —O—, —CO—, —NH—, —CO—NH—, —COO—, —O—COO—, an alkylene group, an arylene group, a heteroarylene group, and combinations thereof. Preferred linking groups are selected.

  The heteroarylene group contains one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom. Examples include a heteroarylene group obtained by removing two hydrogen atoms on a heteroaromatic ring containing one or more heteroatoms selected from the group consisting of a nitrogen atom, an oxygen atom and a sulfur atom. Specific examples of the heteroaromatic ring containing one or more heteroatoms selected from the group consisting of nitrogen atom, oxygen atom and sulfur atom include pyrrole, furan, thiophene, pyrazole, imidazole, triazole, oxazole, isoxazole and oxadiazole. , Thiazole, thiadiazole, indole, carbazole, benzofuran, dibenzofuran, thianaphthene, dibenzothiophene, indazolebenzimidazole, anthranyl, benzisoxazole, benzoxazole, benzothiazole, purine, pyridine, pyridazine, pyrimidine, pyrazine, triazine, quinoline, acridine, Examples thereof include isoquinoline, phthalazine, quinazoline, quinoxaline, naphthyridine, phenanthroline, and pteridine.

  In the general formula (I), the substituted or unsubstituted aliphatic hydrocarbon group represented by X is a substituted or unsubstituted linear or branched alkyl group having 1 to 30 carbon atoms (for example, methyl group, ethyl group). , Iso-propyl group, n-propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, hexadecyl group, octadecyl group, eicosyl group, Isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, neopentyl group, 1-methylbutyl group, isohexyl group, 2-methylhexyl group, etc.), substituted or unsubstituted cyclic group having 3 to 20 carbon atoms Alkyl groups (for example, cyclopentyl group, cyclohexyl group, 1-adamantyl group, 2-norbornyl group, etc.) , An alkenyl group having 2 to 20 carbon atoms (for example, vinyl group bi, 1-propenyl group, 1-butenyl group, 1-methyl-1-propenyl group, etc.), A substituted or unsubstituted phenyl group having 6 to 50 carbon atoms (for example, phenyl group, tolyl group, styryl group, 4-benzoyloxyphenyl group, 4-phenoxycarbonylphenyl group, 4-biphenyl group, 4- (4-octyl group) Oxybenzoyloxy) phenoxycarbonylphenyl group, etc.), substituted or unsubstituted naphthyl groups having 10 to 50 carbon atoms (for example, unsubstituted naphthyl group, etc.), and examples of substituted or unsubstituted heterocyclic groups include: Substituted or unsubstituted 5-membered containing at least one heteroatom (eg, nitrogen, oxygen, sulfur, etc.) Or a 6-membered ring group such as pyrrole, furan, thiophene, pyrazole, imidazole, triazole, oxazole, isoxazole, oxadiazole, thiazole, thiadiazole, indole, carbazole, benzofuran, dibenzofuran, thianaphthene, dibenzothiophene, Indazole benzimidazole, anthranyl, benzisoxazole, benzoxazole, benzothiazole, purine, pyridine, pyridazine, pyrimidine, pyrazine, triazine, quinoline, acridine, isoquinoline, phthalazine, quinazoline, quinoxaline, naphthyridine, phenanthroline, pteridine, morpholine, piperidine, etc. The group of is mentioned.

  In general formula (I), X is preferably a single bond or a substituted or unsubstituted arylene group, more preferably a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, still more preferably a substituted or unsubstituted group. A substituted phenyl group.

R ¹ , R ² and X may be further substituted with one or more substituents if possible. Examples of the substituent include monovalent non-metallic atomic groups excluding hydrogen, halogen atoms (—F, —Br, —Cl, —I), hydroxyl groups, alkoxy groups, aryloxy groups, mercapto groups, alkylthio groups. , Arylthio group, alkyldithio group, aryldithio group, amino group, N-alkylamino group, N, N-dialkylamino group, N-arylamino group, N, N-diarylamino group, N-alkyl-N-aryl Amino group, acyloxy group, carbamoyloxy group, N-alkylcarbamoyloxy group, N-arylcarbamoyloxy group, N, N-dialkylcarbamoyloxy group, N, N-diarylcarbamoyloxy group, N-alkyl-N-arylcarbamoyl Oxy, alkylsulfoxy, arylsulfoxy, acylthio Group, acylamino group, N-alkylacylamino group, N-arylacylamino group, ureido group, N′-alkylureido group, N ′, N′-dialkylureido group, N′-arylureido group, N ′, N '-Diarylureido group, N'-alkyl-N'-arylureido group, N-alkylureido group, N-arylureido group, N'-alkyl-N-alkylureido group, N'-alkyl-N-arylureido Group, N ′, N′-dialkyl-N-alkylureido group, N ′, N′-dialkyl-N-arylureido group, N′-aryl-N-alkylureido group, N′-aryl-N-arylureido Group, N ′, N′-diaryl-N-alkylureido group, N ′, N′-diaryl-N-arylureido group, N′-alkyl-N′-aryl-N-alkyl Raid group, N′-alkyl-N′-aryl-N-arylureido group, alkoxycarbonylamino group, aryloxycarbonylamino group, N-alkyl-N-alkoxycarbonylamino group, N-alkyl-N-aryloxycarbonyl Amino group, N-aryl-N-alkoxycarbonylamino group, N-aryl-N-aryloxycarbonylamino group, formyl group, acyl group, carboxyl group and its conjugate base group, alkoxycarbonyl group, aryloxycarbonyl group, carbamoyl Group, N-alkylcarbamoyl group, N, N-dialkylcarbamoyl group, N-arylcarbamoyl group, N, N-diarylcarbamoyl group, N-alkyl-N-arylcarbamoyl group, alkylsulfinyl group, arylsulfinyl group, alkyl Sulfonyl group, arylsulfonyl group, sulfo group (—SO ₃ H) and its conjugate base group, alkoxysulfonyl group, aryloxysulfonyl group, sulfinamoyl group, N-alkylsulfinamoyl group, N, N-dialkylsulfinamoyl group N-arylsulfinamoyl group, N, N-diarylsulfinamoyl group, N-alkyl-N-arylsulfinamoyl group, sulfamoyl group, N-alkylsulfamoyl group, N, N-dialkylsulfamoyl group Group, N-arylsulfamoyl group, N, N-diarylsulfamoyl group, N-alkyl-N-arylsulfamoyl group, N-acylsulfamoyl group and its conjugate base group, N-alkylsulfonylsulfur group Famoiru group _{(-SO 2 NHSO 2 (alkyl)} ) and its conjugated base group N- aryl acylsulfamoyl group _{(-SO 2 NHSO 2 (aryl)} ) and its conjugated base group, N- alkylsulfonylcarbamoyl group (-CONHSO ₂ (alkyl)) and its conjugated base group, N- aryl sulfonyl carbamoyl group (—CONHSO ₂ (aryl)) and its conjugate base group, alkoxysilyl group (—Si (Oalkyl) ₃ ), aryloxysilyl group (—Si (Oaryl) ₃ ), hydroxysilyl group (—Si (OH) ₃ ) And its conjugate base group, phosphono group (—PO ₃ H ₂ ) and its conjugate base group, dialkylphosphono group (—PO ₃ (alkyl) ₂ ), diarylphosphono group (—PO ₃ (aryl) ₂ ), alkyl Arylphosphono group (—PO ₃ (alkyl) (aryl)), monoalkylphosphono group (—PO ₃ H (alkyl)) and its conjugate base group, monoarylphosphono group (—PO ₃ H (aryl)) and its conjugate base group, phosphonooxy group (—OPO ₃ H ₂ ) and its conjugate base group, dialkylphosphonooxy Group (—OPO ₃ (alkyl) ₂ ), diarylphosphonooxy group (—OPO ₃ (aryl) ₂ ), alkylarylphosphonooxy group (—OPO ₃ (alkyl) (aryl)), monoalkylphosphonooxy group (—OPO ₃ H (alkyl)) and its conjugate base group, monoarylphosphonooxy group (—OPO ₃ H (aryl)) and its conjugate base group, cyano group, nitro group, aryl group, alkenyl group, alkynyl group Is mentioned. Further, these substituents may combine with each other or with a substituted hydrocarbon group to form a ring, if possible.

  In the general formula (I), Z represents a substituent having a polymerizable group, and specifically includes an acrylate group, a methacrylate group, a styryl group, a vinyl ketone group, a butadiene group, a vinyl ether group, an oxiranyl group, an aziridinyl group, and an oxetane. Substituents containing groups and the like can be mentioned. Preferred are substituents containing (meth) acrylate groups, styryl groups, oxiranyl groups or oxetane groups, and most preferred are substituents containing (meth) acrylate groups and styryl groups.

In one preferred embodiment of the compound represented by the general formula (I), R ¹ and R ² each represent a hydrogen atom, Z represents a group represented by the following general formula (II), or an oxiranyl moiety or an oxetane moiety. It is the aspect which is group which has.

一般式（II）中、Ｒ³は水素原子又はメチル基であり、Ｌは、−Ｏ−、−ＣＯ−、−ＮＨ−、−ＣＯ−ＮＨ−、−ＣＯＯ−、−Ｏ−ＣＯＯ−、アルキレン基、アリーレン基、ヘテロ環基、及びそれらの組み合わせから選ばれる二価の連結基である。

In the general formula (II), R ³ is a hydrogen atom or a methyl group, and L is —O—, —CO—, —NH—, —CO—NH—, —COO—, —O—COO—, alkylene. A divalent linking group selected from a group, an arylene group, a heterocyclic group, and combinations thereof.

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

The polymer used together with the compound represented by the general formula (I) is not particularly limited, but a polymer that can be chemically bonded to the compound represented by the general formula (I) is preferable.
Polyvinyl alcohol is preferred as the polymer that can be chemically bonded to boron in the general formula (I). The compound represented by the general formula (I) can be indirectly bonded to the polymerizable main chain carbon of polyvinyl alcohol via an ether bond. That is, the polymer film of the present invention is preferably a polyvinyl alcohol derivative represented by the following general formula (III). A polymer film made of a polyvinyl alcohol derivative represented by the following general formula (III) is particularly useful as a liquid crystal alignment film.

However, in general formula (III), l is 10 to 99.9 mol%, m is 0 to 70 mol%, n is 0.01 to 80 mol%, and l is 20 to 20 in the condition of l + m + n = 100. ~ 99 mol%, m is preferably 0 to 50 mol%, n is preferably 0.1 to 50 mol%, l is 50 to 99 mol%, m is 0 to 30 mol%, and n is 0.1 to 30 mol% Is more preferable.
About X and Z in Formula (III), it is synonymous with each in Formula (I), and its preferable range is also the same.

  The molecular weight range of the polymer represented by the general formula (III) is preferably 1000 to 500,000 in terms of weight average molecular weight, more preferably 2000 to 300,000, and further preferably 3000 to 200,000. preferable.

  Examples of the polymer represented by the general formula (III) are shown below, but the present invention is not limited by the following specific examples.

  In the general formula (III-1), examples of l, m, n and molecular weight are shown below.

In the general formula (III-2), examples of l, m, n and molecular weight are shown below.

In the general formula (III-3), examples of l, m, n and molecular weight are shown below.

In the general formula (III-4), examples of l, m, n and molecular weight are shown below.

  In the general formula (II-1), examples of l, m, n and molecular weight are shown below.

  In the general formula (II-2), examples of l, m, n and molecular weight are shown below.

  In the general formula (II-3), examples of l, m, n and molecular weight are shown below.

  In the general formula (II-4), examples of l, m, n and molecular weight are shown below.

  In the general formula (II-5), examples of l, m, n and molecular weight are shown below.

  The polymer film of the present invention is prepared by preparing a composition containing the compound represented by the general formula (I) and a polymer, for example, a coating solution, and applying and drying the coating solution on the surface of a plastic film or the like. Can be formed. In the case of producing a polymer film composed of a polymer formed by chemically combining a compound represented by the general formula (I) and a polymer, the compound of the general formula (I) and the polymer are included. After coating the coating liquid on the surface of a support or the like, the reaction may be allowed to proceed simultaneously with or after drying to form a film. Further, after the compound of the general formula (I) and the polymer are reacted to obtain a chemically bonded polymer, a coating solution containing the polymer is prepared, and the coating solution is applied to the surface of a support or the like. It is also possible to form a polymer film made of the polymer by coating and drying.

  The polyvinyl alcohol derivative represented by the general formula (III) can be produced by reacting boron in the general formula (I) with polyvinyl alcohol. As a solvent (reaction solvent) for dissolving polyvinyl alcohol and the boronic acid compound represented by the general formula (I), various solvents from polar solvents to nonpolar solvents can be used. Examples thereof include polar solvents such as N, N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N, N-dimethylacetamide and pyridine, ethers such as tetrahydrofuran and 1,2-dimethoxyethane, dichloromethane, chloroform. And non-polar solvents such as benzene and hexane. These may be used alone or in combination. DMSO and ethers are particularly preferable.

  The reaction temperature when reacting the compound represented by the general formula (I) with polyvinyl alcohol is generally in the range of −80 to 150 ° C., preferably in the range of −20 to 120 ° C., particularly −5 to A range of 90 ° C. is preferred. In the reaction, the ratio (preparation ratio) between the compound having the specific group and the repeating unit of polyvinyl alcohol is preferably 1/100 to 1/1 (compound / repeating unit), particularly 1/50 to 1 in terms of molar ratio. / 5 is preferred. In order to obtain the desired polymer from the reaction mixture, the polymer is usually purified by reprecipitation by adding a poor solvent to the reaction mixture, dialysis, or freeze-drying. These operations can be repeated as appropriate and / or combined appropriately.

The polymer film of the present invention can be used for various applications. Since the polymer film of the present invention contains a polymerizable boron compound, when it is used for the lower layer or intermediate layer of a laminate having a plurality of layers, the compound and boron in the layer formed on the surface are strong. By the interaction, the adhesion between the layers is improved, and even when stored or used for a long period of time, peeling or the like hardly occurs. Further, when the boron compound has a polymerizable group, the layers can be chemically bonded by ultraviolet irradiation or the like, and the adhesion can be further improved.
Further, a polymer film composed of a polymer in which a polymerizable compound represented by the general formula (I) and polyvinyl alcohol are chemically bonded, particularly a high molecular weight composed of a polyvinyl alcohol derivative represented by the general formula (III). The molecular film is useful as a liquid crystal alignment film. Hereinafter, a retardation plate produced using the polymer film of the present invention as a liquid crystal alignment film will be described.

[Phase difference plate]
One embodiment of the present invention relates to a retardation plate in which a transparent support, an alignment film that is the polymer film, and an optically anisotropic layer made of a liquid crystalline compound are provided in this order. The polymer of the alignment film and the liquid crystalline compound of the optically anisotropic layer are preferably chemically bonded at the interface. The preferable form of the retardation film of this aspect is as follows.
1) The polymer of the alignment film is substituted with at least two hydroxyl groups by boron in the boronic acid compound represented by the general formula (I) being indirectly bonded to the main chain via an ether bond. Formed from polyvinyl alcohol.
2) The liquid crystalline compound used for forming the optically anisotropic layer is a discotic liquid crystalline compound having a group having a vinyl part, an oxiranyl part or an aziridinyl part.

Below, the phase difference plate of this aspect is demonstrated in detail.
One embodiment of the retardation plate of this aspect includes an alignment film comprising as a main component the boronic acid-modified polyvinyl alcohol on a support, and a liquid crystal compound that is alignment-controlled by the alignment film and fixed in the alignment state. An optically anisotropic layer containing FIG. 1 is a schematic cross-sectional view of an embodiment of the retardation plate of this aspect. The retardation plate (05) shown in FIG. 1 has an alignment film (02) made of a polymer and an optically anisotropic layer (03) on a transparent support (01). The alignment film (02) can be formed on the surface of the transparent support (01) such as a plastic film by coating or vapor deposition. After rubbing the surface of the alignment film (02), when a composition (coating liquid) containing the liquid crystal compound (04) is applied to the rubbing surface, the molecules of the liquid crystal compound are controlled in alignment by the rubbing direction, and the desired Oriented at an orientation angle. Thereafter, liquid crystal molecules are fixed in the alignment state to form an optically anisotropic layer (03), and a retardation plate (05) is obtained.

  Further, as shown in FIG. 2, the polarizing film (07) is sandwiched between the optically anisotropic layer (05) and the transparent support (01) side and the other transparent support (06). Thus, a polarizing plate (08) can be produced.

  Furthermore, a liquid crystal display device can be manufactured by disposing the polarizing plate (08) on both sides of a liquid crystal cell made of twisted-aligned nematic liquid crystal. However, the polarizing axes of both polarizing plates are arranged to be orthogonal to each other.

(1) Alignment film In the retardation plate of this embodiment, the polymer film of the present invention is used as the alignment film. Among them, it is preferable to consist of a polymer in which the boron compound represented by the general formula (I) and polyvinyl alcohol are chemically bonded, and it is more preferable to consist of a polyvinyl alcohol derivative represented by the general formula (III). .

  The alignment film can be formed by applying a coating liquid containing a polymer for alignment film on the surface of the support and then drying. The surface is preferably subjected to a rubbing treatment. The rubbing treatment can be carried out by rubbing the surface of the polymer coating layer several times with paper or cloth in a certain direction (usually the longitudinal direction). As a method other than rubbing, liquid crystal alignment can be imparted by applying an electric field, applying a magnetic field, or irradiating light. As a method for imparting liquid crystal alignment, an alignment film formed by a rubbing treatment of a polymer is particularly preferable.

(2) Optically anisotropic layer The optically anisotropic layer included in the retardation plate of this embodiment is composed of a liquid crystal compound, preferably a discotic liquid crystal compound, and other compounds such as a polymerizable compound and a polymerizable initiator as desired. It can be formed from a composition containing additives. The composition is prepared, for example, as a coating solution. The coating liquid can be formed, for example, by coating the surface of the alignment film of this embodiment formed on a support and aligning and fixing the liquid crystalline compound. After aligning and fixing the liquid crystalline compound, the support may be peeled off.

(2) -1 Formation Method of Optically Anisotropic Layer The optically anisotropic layer is formed on a support as described above by applying a coating solution prepared by dissolving a liquid crystalline compound in a solvent capable of being dissolved. And it can produce by apply | coating on the orientation film | membrane of this aspect to which orientation was provided. Moreover, although it may be formed by vapor deposition if possible, it is preferably formed by coating. Known coating methods include curtain coating, dip coating, spin coating, print coating, spray coating, slot coating, roll coating, slide coating, blade coating, gravure coating, and wire bar method. The coating method is mentioned. Next, the solvent used at 25 ° C. to 130 ° C. is dried, and at the same time, the liquid crystalline compound is oriented, and further fixed by ultraviolet irradiation or the like as required, thereby forming an optically anisotropic layer of the liquid crystalline compound. . It is preferable to use ultraviolet rays for light irradiation for polymerization. The irradiation energy is preferably 20 mJ / cm ^{2 to} 50 J / cm ² , and more preferably 100 mJ / cm ^{2 to} 800 mJ / cm ² . In order to accelerate the photopolymerization reaction, light irradiation may be performed under heating conditions. The thickness of the optically anisotropic layer formed in this way varies depending on the use, for example, the preferred range depending on the optimum retardation value, but is generally 0.1 to 10 μm. It is preferable that it is 0.5-5 micrometers.

(2) -2 Material used for forming optically anisotropic layer The optically anisotropic layer contains a liquid crystalline compound fixed in an aligned state. For example, when the liquid crystalline compound has a polymerizable group, it can be easily fixed by a polymerization reaction, and when a polymerizable group is present in the alignment film, the alignment film layer and the optically anisotropic layer are interfaced. It is preferable because it can be chemically bonded to improve the adhesion between both layers. As the liquid crystal compound, a discotic liquid crystal compound having a discotic molecular shape is preferable.
(2) -2-1 Discotic liquid crystalline compounds Discotic liquid crystalline compounds are disclosed in various literatures (C. Destrade et al., Mol. Crysr. Liq. Cryst., Vol. 71, page 111 (1981); Japan). Chemistry Association, Quarterly Review, No. 22, Liquid Crystal Chemistry, Chapter 5, Chapter 10 Section 2 (1994); B. Kohne et al., Angew. Chem. Soc. Chem. Comm., Page 1794. (1985); J. Zhang et al., J. Am. Chem. Soc., Vol. 116, page 2655 (1994)). The polymerization of discotic liquid crystalline molecules is described in JP-A-8-27284. In order to fix the discotic liquid crystalline molecules by polymerization, it is necessary to bond a polymerizable group as a substituent to the discotic core of the discotic liquid crystalline molecules. However, when the polymerizable group is directly connected to the disc-shaped core, it becomes difficult to maintain the orientation state in the polymerization reaction. Therefore, a linking group is introduced between the discotic core and the polymerizable group. Accordingly, the discotic liquid crystalline molecule having a polymerizable group is preferably a compound represented by the following general formula (IV).

Formula (IV)
D (-MP) _n
(In the general formula, D is a discotic core, M is a divalent linking group, P is a polymerizable group, and n is an integer of 4 to 12.)

  Examples of the disk-shaped core (D) of the general formula (IV) are shown below. In each of the following examples, MP (or PM) means a combination of a divalent linking group (M) and a polymerizable group (P).

  In the general formula (IV), the divalent linking group (M) is selected from the group consisting of an alkylene group, an alkenylene group, an arylene group, —CO—, —NH—, —O—, —S—, and combinations thereof. It is preferable that it is a bivalent coupling group. The divalent linking group (M) is a group in which at least two divalent groups selected from the group consisting of an alkylene group, an alkenylene group, an arylene group, -CO-, -NH-, -O-, and S- are combined. More preferably. The divalent linking group (M) is most preferably a group obtained by combining at least two divalent groups selected from the group consisting of an alkylene group, an alkenylene group, an arylene group, -CO- and O-. The alkylene group preferably has 1 to 12 carbon atoms. The alkenylene group preferably has 2 to 12 carbon atoms. The number of carbon atoms in the arylene group is preferably 6-10. The alkylene group, alkenylene group and arylene group may have a substituent (eg, alkyl group, halogen atom, cyano, alkoxy group, acyloxy group).

Examples of the divalent linking group (M) are shown below. The left side is bonded to the discotic core (D), and the right side is bonded to the polymerizable group (P). AL represents an alkylene group or an alkenylene group, and AR represents an arylene group.
M1: -AL-CO-O-AL-
M2: -AL-CO-O-AL-O-
M3: -AL-CO-O-AL-O-AL-
M4: -AL-CO-O-AL-O-CO-
M5: -CO-AR-O-AL-
M6: -CO-AR-O-AL-O-
M7: -CO-AR-O-AL-O-CO-
M8: -CO-NH-AL-
M9: -NH-AL-O-
M10: —NH—AL—O—CO—

M11: -O-AL-
M12: -O-AL-O-
M13: -O-AL-O-CO-
M14: -O-AL-O-CO-NH-AL-
M15: -O-AL-S-AL-
M16: -O-CO-AL-AR-O-AL-O-CO-
M17: -O-CO-AR-O-AL-CO-
M18: -O-CO-AR-O-AL-O-CO-
M19: -O-CO-AR-O-AL-O-AL-O-CO-
M20: -O-CO-AR-O-AL-O-AL-O-AL-O-CO-
M21: -S-AL-
M22: -S-AL-O-
M23: -S-AL-O-CO-
M24: -S-AL-S-AL-
M25: -S-AR-AL-

  The polymerizable group (P) of the general formula (IV) is determined according to the type of polymerization reaction. Examples of the polymerizable group (P) are shown below.

  The polymerizable group (P) is preferably an unsaturated polymerizable group (P1, P2, P3, P7, P8, P15, P16, P17) or an epoxy group (P6, P18). More preferably, it is most preferably an ethylenically unsaturated polymerizable group (P1, P7, P8, P15, P16, P17). In general formula (IV), n is an integer of 4-12. A specific number is determined according to the type of discotic core (D). In addition, although the combination of several M and P may differ, it is preferable that it is the same. Two or more kinds of discotic liquid crystalline molecules (for example, a molecule having an asymmetric carbon atom in a divalent linking group and a molecule not having it) may be used in combination.

  The liquid crystalline molecule is preferably fixed while maintaining the alignment state, and the fixing is performed by a polymerization reaction of a polymerizable group (P represented by the general formula (IV)) introduced into the liquid crystalline molecule. preferable. The purpose of fixation is to develop and stabilize the desired optical anisotropy, and as a result, the liquid crystallinity may be lost. For that purpose, it is preferable to contain a polymerization initiator in the coating solution. The polymerization reaction includes a thermal polymerization reaction using a thermal polymerization initiator, a photopolymerization reaction using a photopolymerization initiator, and EB curing using an electron beam. Among these, photopolymerization reaction (photocuring) and EB curing are preferable. Examples of polymerization initiators that generate radicals by the action of light include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (described in US Pat. No. 2,448,828), α -Combination of hydrocarbon-substituted aromatic acyloin compound (described in US Pat. No. 2,722,512), polynuclear quinone compound (described in US Pat. Nos. 3,046,127 and 2,951,758), triarylimidazole dimer and p-aminophenyl ketone (Described in US Pat. No. 3,549,367), acridine and phenazine compounds (JP-A-60-105667, US Pat. No. 4,239,850) and oxadiazole compounds (described in US Pat. No. 4,212,970), acetophenone compounds , Benzoy Preferred are ether ether compounds, benzyl compounds, benzophenone compounds, thioxanthone compounds, and the like. Examples of the acetophenone compound include 2,2-diethoxyacetophenone, 2-hydroxymethyl-1-phenylpropan-1-one, 4′-isopropyl-2-hydroxy-2-methyl-propiophenone, 2-hydroxy -2-methyl-propiophenone, p-dimethylaminoacetone, p-tert-butyldichloroacetophenone, p-tert-butyltrichloroacetophenone, p-azidobenzalacetophenone and the like. Examples of the benzyl compound include benzyl, benzyl dimethyl ketal, benzyl-β-methoxyethyl acetal, 1-hydroxycyclohexyl phenyl ketone and the like. Examples of the benzoin ether compounds include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin-n-propyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, and benzoin isobutyl ether. Examples of the benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, Michler's ketone, 4,4'-bisdiethylaminobenzophenone, 4,4'-dichlorobenzophenone, and the like. Examples of the thioxanthone compound include thioxanthone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, and the like. Among such photosensitive radical polymerization initiators composed of aromatic ketones, acetophenone compounds and benzyl compounds are particularly preferable in terms of curing characteristics, storage stability, odor, and the like. One or more photosensitive radical polymerization initiators composed of these aromatic ketones can be used in combination according to the desired performance. In addition to a polymerization initiator, a sensitizer may be used for the purpose of increasing sensitivity. Examples of the sensitizer include n-butylamine, triethylamine, tri-n-butylphosphine, thioxanthone and the like.

  Multiple photopolymerization initiators may be combined, and the amount used is preferably 0.01 to 20% by mass, more preferably 0.5 to 5% by mass, based on the solid content of the coating solution. The amount of the photopolymerization initiator used is preferably 0.01 to 20% by mass, more preferably 0.05 to 5% by mass, based on the solid content of the coating solution. It is preferable to use ultraviolet rays for light irradiation for polymerization of liquid crystalline molecules.

(2) -2-3 Other Additives Additives other than those described above can also be added to the coating liquid for forming an optically anisotropic layer. For example, a plasticizer, a monomer, a surfactant, a cellulose ester, an alignment control agent, a chiral agent, and the like can be given. The orientation control agent will be described in detail below. The alignment control agent in the present invention is added to the liquid crystal compound coating solution, and after coating, the liquid crystal compound layer is unevenly distributed on the surface of the liquid crystal compound layer, that is, on the air interface side, thereby aligning the liquid crystal compound on the air interface side. Means a compound that contributes to controlling Depending on the structure of this alignment control agent, the liquid crystalline compound can be aligned substantially vertically on the air interface side, or conversely horizontally aligned, but when using a discotic liquid crystalline compound in the present invention, Additives that are oriented substantially perpendicularly on the air interface side are preferred. For example, in the case of a discotic liquid crystalline compound, a compound represented by the following general formula (VI) described in JP-A No. 2000-344734 is exemplified.

General formula (VI)
(Hb−) _m L (−Bu) _n
In general formula (V), Hb is a fluorine-substituted alkyl group having 1 to 40 carbon atoms, a fluorine-substituted aryl group having 6 to 40 carbon atoms, an alkyl group having 6 to 60 carbon atoms, and the number of carbon atoms. Is a hydrophobic group selected from the group consisting of 1 to 60 alkyl-substituted oligosiloxanoxy groups, Bu is a group having an excluded volume effect containing at least two cyclic structures, and L is a (m + n) -valent linkage And m and n are each independently an integer of 1 to 12.

  Preferred examples of the orientation control agent represented by the general formula (VI) include low-molecular orientation control agents in which a trihydroxybenzene skeleton and a triazine skeleton are substituted with a fluorine alkyl group, a long-chain alkyl group, or an aryl group. Specific examples of the alignment control agent for vertically aligning the discotic liquid crystal on the air interface side include, for example, the following D-1 and the like, and D-2 and the like as the alignment control agent for horizontally aligning. Can be mentioned.

  In addition, the alignment controller may be a polymer compound as shown below. The polymer alignment control agent added may be a polymer that can be dissolved in the liquid crystal layer coating solution. An example of a preferred polymer alignment controller is shown below.

Polypropylene oxide polytetramethylene oxide poly-ε-caprolactone poly-ε-caprolactone diol poly-ε-caprolactone triol polyvinyl acetate polymelamine poly (ethylene adipate)
Poly (1,4-butylene adipate)
Poly (1,4-butylene glutarate)
Poly (1,2-butylene glycol)
Poly (1,4-butylene succinate)
Poly (1,4-butylene terephthalate)
polyethylene terephthalate)
Poly (2-methyl-1,3-propylene adipate)
Poly (2-methyl-1,3-propylene glutarate)
Poly (neopentyl glycol adipate)
Poly (neopentyl glycol sebacate)
Poly (1,3-propylene adipate)
Poly (1,3-propylene glutarate)
Polyvinyl butyral polyvinyl formal polyvinyl acetal polyvinyl propanal polyvinyl hexanal polyvinyl pyrrolidone polyacrylic acid ester polymethacrylic acid ester poly (3-hydroxybutyric acid)

  Further, a polymer containing a structural unit composed of a monomer having at least one fluorinated alkyl group is more preferably used. For example, the following polymer D-3 is preferably used.

  The addition amount of the alignment control agent is preferably 0.05% by mass to 10% by mass with respect to the liquid crystal compound in the liquid crystal composition to which the control agent is added. More preferably, it is 0.1 mass%-5 mass%.

  As the solvent used for preparing the coating liquid for forming the optically anisotropic layer, an organic solvent is preferable. Examples of organic solvents include amides (eg, N, N-dimethylformamide), sulfoxides (eg, dimethyl sulfoxide), heterocyclic compounds (eg, pyridine), hydrocarbons (eg, toluene, hexane) alkyl halides (eg, Chloroform (dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, 2-butanone, methyl isobutyl ketone, cyclohexanone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane) and the like. . Of these, alkyl halides and ketones are preferred. Two or more organic solvents may be used in combination.

  The solid content concentration of the liquid crystal compound and other additives in the coating solution is preferably 0.1% by mass to 60% by mass, more preferably 0.5% by mass to 50% by mass, and 2% by mass to 40% by mass. % Is more preferable. The viscosity of the coating solution is preferably 0.01 cp to 100 cp, and more preferably 0.1 cp to 50 cp.

(3) Support The retardation plate of this aspect has a support. The support is not necessarily the same as the support used at the time of production, and after the optically anisotropic layer is produced, it may be transferred from the temporary support used at the production to another support. It is preferable to use a polymer film that is transparent and has small optical anisotropy and small wavelength dispersion as the support. Here, that the support is transparent means that the light transmittance is 80% or more. Specifically, the small chromatic dispersion means that the ratio of Re400 / Re700 is preferably less than 1.2. Specifically, the small optical anisotropy means that in-plane retardation (Re) is preferably 20 nm or less, and more preferably 10 nm or less. The transparent support preferably has a roll-like or rectangular sheet-like shape, and the optically anisotropic layer can be laminated using the roll-like transparent support and then cut into a required size. preferable. Examples of the polymer include cellulose ester, polycarbonate, polysulfone, polyethersulfone, polyacrylate and polymethacrylate. Cellulose esters are preferred, acetyl cellulose is more preferred, and triacetyl cellulose is most preferred. The polymer film is preferably formed by a solvent cast method. The thickness of the transparent support is preferably 20 to 500 μm, and more preferably 50 to 200 μm. In order to improve the adhesion between the transparent support and the layer (adhesive layer, alignment film or optically anisotropic layer) provided on the transparent support, surface treatment (eg, glow discharge treatment, corona discharge treatment, ultraviolet light ( UV) treatment, flame treatment). An adhesive layer (undercoat layer) may be provided on the transparent support.

(4) Polarizing plate After a linearly polarizing film or a transparent protective film is bonded to the retardation plate of this embodiment to form a polarizing plate, it may be used for a liquid crystal display element. The polarizing film and the transparent protective film will be described below.

(4) -1 Polarizing film Examples of the polarizing film include an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine polarizing film and the dye polarizing film are generally produced using a polyvinyl alcohol film. The transmission axis of the polarizing film corresponds to a direction perpendicular to the stretching direction of the film. When the discotic liquid crystalline compound is used for the optically anisotropic layer, the transmission axis of the polarizing film is arranged so as to be substantially parallel to the surface of the discotic liquid crystalline molecule on the alignment film side. . When a rod-like liquid crystal compound is used, the transmission axis of the polarizing film is arranged so as to be substantially parallel to the major axis direction (slow axis) of the rod-like liquid crystal molecule. Usually, it is preferable to bond to the support side of the retardation plate, but if necessary, it may be bonded to the optically anisotropic layer side.

(4) -2 Transparent protective film It is preferable that a transparent polymer film is used as a transparent protective film on the optically anisotropic layer side of the retardation plate. That the protective film is transparent means that the light transmittance is 80% or more. As the transparent protective film, generally a cellulose ester film, preferably a triacetyl cellulose film is used. The cellulose ester film is preferably formed by a solvent cast method. The thickness of the transparent protective film is preferably 20 to 500 μm, and more preferably 50 to 200 μm.

(5) Liquid crystal display device The phase difference plate of this aspect can be used for a liquid crystal display device having liquid crystal cells of various display modes. As described above, the retardation plate of this embodiment is useful as an optical compensation sheet for liquid crystal cells. As for the optical compensation sheet having an optically anisotropic layer made of liquid crystalline molecules, TN (Twisted Nematic), IPS (In-Plane Switching), FLC (Ferroelectric Liquid Crystal Bend), OCB (Optically Compensatory Bend) Super Twisted Nematic), VA (Vertically Aligned), ECB (Electrically Controlled Birefringence), reflection type is TN, HAN (Hybrid Aligned Nematic), G . The retardation plate and polarizing plate obtained by the present invention can be applied to various liquid crystal display modes depending on the alignment state, but the optically anisotropic layer and polarizing plate obtained by the present invention are suitably applied to a TN mode liquid crystal cell. it can.

[Optically anisotropic layer (for in-plane switching mode (IPS))]
Next, an optically anisotropic layer that can be suitably used in an in-plane switching mode display device will be described. In this embodiment, the optically anisotropic layer comprises a liquid crystal composition containing at least one rod-like liquid crystalline compound. The rod-like liquid crystal compound may be a low molecular compound or a high molecular compound, but is preferably a low molecular compound in order to quickly form a desired alignment state. Moreover, in order to fix the orientation state and obtain a film, it is preferable to have a polymerizable group. The rod-like liquid crystal compound having polymerizability may be used alone or in a mixture using some of the polymerizable or non-polymerizable rod-like liquid crystal compounds. Individual liquid crystalline compounds used alone or in combination may form a nematic liquid crystal phase, a smectic liquid crystal phase, or a cholesteric liquid crystal phase. In addition, as described later, when applying the liquid crystal composition, a composition containing an additive such as a solvent or a polymerization initiator is applied, but as a liquid crystal composition in a state where the solvent is volatilized in the process of heating and drying. Those having a smectic liquid crystal phase in a temperature range in which the orientation is fixed are preferably used.

(Bar-shaped liquid crystalline compound)
The retardation film of this embodiment is formed from a composition containing a rod-like liquid crystalline compound. Examples of the rod-like liquid crystalline compound include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines. , Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used. In addition to the low-molecular liquid crystals as described above, polymer liquid crystals can also be used. As the rod-like liquid crystalline compound, those having a partial structure capable of causing polymerization or a crosslinking reaction by actinic rays, electron beams, heat, or the like are suitably used. The number of the partial structures is 1 to 6, preferably 1 to 3. As described above, the rod-like liquid crystalline molecules that can be used in the present invention preferably have a polymerizable group in order to fix the alignment state. The polymerizable group is preferably a radically polymerizable unsaturated group, and specific examples thereof include a polymerizable group and a polymerizable liquid crystal compound described in JP-T-2000-514202 or JP-A-2002-62427. In the retardation film of the present invention, the rod-like liquid crystal compound is preferably oriented perpendicular to the substrate or support, that is, perpendicular to the film surface of the retardation film.

  As described above, it is more preferable to fix the alignment of the rod-like liquid crystalline molecules by polymerization. Chem. 190, 2255 (1989), Advanced Materials 5, 107 (1993), U.S. Pat. Nos. 4,683,327, 5,622,648, 5,770,107, WO 95/22586, 95/24455, 97/97. No. 0600, No. 98/23580, No. 98/52905, JP-A-1-272551, JP-A-6-16616, JP-A-7-110469, JP-A-11-80081, and Japanese Patent Application No. 2001-64627 These compounds can be used. More preferably, it is a compound represented by the following general formula (V).

^{(IV) Q 1 -L 1 -Cy} 1 -L 2 - (Cy 2 -L 3) n -Cy 3 -L 4 -Q 2
In the formula, Q ¹ and Q ² are each independently a polymerizable group, L ¹ and L ⁴ are each independently a divalent linking group, and L ² and L ³ are each independently a single bond or a divalent group. It is a linking group, Cy ¹ , Cy ² and Cy ³ are divalent cyclic groups, and n is 0, 1 or 2.

Q ¹ and Q ² are each independently a polymerizable group. The polymerization reaction of the polymerizable group is preferably addition polymerization (including ring-opening polymerization) or condensation polymerization. In other words, the polymerizable group is preferably a functional group capable of addition polymerization reaction or condensation polymerization reaction. Examples of polymerizable groups are shown below.

L ¹ and L ⁴ are each independently a divalent linking group. L ¹ and L ⁴ are each independently selected from the group consisting of —O—, —S—, —CO—, —NR ² —, a divalent chain group, a divalent cyclic group, and combinations thereof. A valent linking group is preferred. R ² is an alkyl group having 1 to 7 carbon atoms or a hydrogen atom. R ² is preferably an alkyl group having 1 to 4 carbon atoms or a hydrogen atom, more preferably a methyl group, an ethyl group or a hydrogen atom, and most preferably a hydrogen atom. The example of the bivalent coupling group which consists of a combination is shown below. Here, the left side is coupled to Q (Q ¹ or Q ² ), and the right side is coupled to Cy (Cy ¹ or Cy ³ ).

L-1: —CO—O—divalent chain group—O—
L-2: —CO—O—divalent chain group —O—CO—
L-3: —CO—O—divalent chain group —O—CO—O—
L-4: -CO-O-divalent chain group -O-divalent cyclic group-
L-5: —CO—O—divalent chain group—O—divalent cyclic group—CO—O—
L-6: -CO-O-divalent chain group -O-divalent cyclic group -O-CO-
L-7: -CO-O-divalent chain group-O-divalent cyclic group-divalent chain group-
L-8: -CO-O-divalent chain group-O-divalent cyclic group-divalent chain group-CO-O-
L-9: -CO-O-divalent chain group-O-divalent cyclic group-divalent chain group-O-CO-
L-10: —CO—O—divalent chain group—O—CO—divalent cyclic group—
L-11: -CO-O-divalent chain group-O-CO-divalent cyclic group-CO-O-
L-12: -CO-O-divalent chain group -O-CO-divalent cyclic group -O-CO-
L-13: —CO—O—Divalent chain group—O—CO—Divalent cyclic group—Divalent chain group—L-14: —CO—O—Divalent chain group—O -CO-divalent cyclic group-divalent chain group-CO-O-
L-15: -CO-O-divalent chain group-O-CO-divalent cyclic group-divalent chain group-O-CO-
L-16: —CO—O—divalent chain group—O—CO—O—divalent cyclic group—
L-17: -CO-O-divalent chain group -O-CO-O-divalent cyclic group -CO-O-
L-18: -CO-O-divalent chain group -O-CO-O-divalent cyclic group -O-CO-
L-19: —CO—O—divalent chain group—O—CO—O—divalent cyclic group—divalent chain group—
L-20: -CO-O-divalent chain group-O-CO-O-divalent cyclic group-divalent chain group-CO-O-
L-21: -CO-O-divalent chain group-O-CO-O-divalent cyclic group-divalent chain group-O-CO-

  The divalent chain group means an alkylene group, a substituted alkylene group, an alkenylene group, a substituted alkenylene group, an alkynylene group, or a substituted alkynylene group. An alkylene group, a substituted alkylene group, an alkenylene group and a substituted alkenylene group are preferred, and an alkylene group and an alkenylene group are more preferred. The alkylene group may have a branch. The alkylene group preferably has 1 to 12 carbon atoms, more preferably 2 to 10 carbon atoms, and most preferably 2 to 8 carbon atoms. The alkylene part of the substituted alkylene group is the same as the above alkylene group. Examples of the substituent include a halogen atom. The alkenylene group may have a branch. The alkenylene group preferably has 2 to 12 carbon atoms, more preferably 2 to 10 carbon atoms, and most preferably 2 to 8 carbon atoms. The alkenylene part of the substituted alkenylene group is the same as the above alkenylene group. Examples of the substituent include a halogen atom. The alkynylene group may have a branch. The alkynylene group preferably has 2 to 12 carbon atoms, more preferably 2 to 10 carbon atoms, and most preferably 2 to 8 carbon atoms. The alkynylene part of the substituted alkynylene group is the same as the above alkynylene group. Examples of the substituent include a halogen atom.

  Specific examples of the divalent chain group include ethylene, propylene, tetramethylene, 2-methyl-1,4-butylene, pentamethylene, hexamethylene, octamethylene, 2-butenylene, 2-butynylene and the like.

The definition and examples of the divalent cyclic group are the same as those of Cy ¹ , Cy ² and Cy ³ described later.

L ^{2 and} L ³ are each independently a single bond or a divalent linking group. L ² and L ³ are each independently two selected from the group consisting of —O—, —S—, —CO—, —NR ² —, a divalent chain group, a divalent cyclic group, and combinations thereof. A valent linking group or a single bond is preferred. R ² is an alkyl group having 1 to 7 carbon atoms or a hydrogen atom, preferably an alkyl group having 1 to 4 carbon atoms or a hydrogen atom, and is a methyl group, an ethyl group or a hydrogen atom. Is more preferable, and a hydrogen atom is most preferable. The divalent chain group and the divalent cyclic group have the same definitions as L ¹ and L ⁴ .

In the formula (IV), n is 0, 1 or 2. When n is 2, two L ³ may be the same or different, and two Cy ² may be the same or different. n is preferably 1 or 2, and more preferably 1.

In formula (IV), Cy ¹ , Cy ² and Cy ³ are each independently a divalent cyclic group. The ring contained in the cyclic group is preferably a 5-membered ring, a 6-membered ring, or a 7-membered ring, more preferably a 5-membered ring or a 6-membered ring, and most preferably a 6-membered ring. The ring contained in the cyclic group may be a condensed ring. However, it is more preferably a monocycle than a condensed ring. The ring contained in the cyclic group may be any of an aromatic ring, an aliphatic ring, and a heterocyclic ring. Examples of the aromatic ring include a benzene ring and a naphthalene ring. Examples of the aliphatic ring include a cyclohexane ring. Examples of the heterocyclic ring include a pyridine ring and a pyrimidine ring. As the cyclic group having a benzene ring, 1,4-phenylene is preferable. As the cyclic group having a naphthalene ring, naphthalene-1,5-diyl and naphthalene-2,6-diyl are preferable. The cyclic group having a cyclohexane ring is preferably 1,4-cyclohexylene. As the cyclic group having a pyridine ring, pyridine-2,5-diyl is preferable. The cyclic group having a pyrimidine ring is preferably pyrimidine-2,5-diyl.

  The cyclic group may have a substituent. Examples of the substituent include a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 5 carbon atoms, a halogen-substituted alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. , An alkylthio group having 1 to 5 carbon atoms, an acyloxy group having 2 to 6 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, a carbamoyl group, and an alkyl-substituted carbamoyl group having 2 to 6 carbon atoms And an acylamino group having 2 to 6 carbon atoms.

  Examples of the polymerizable liquid crystal compound represented by the formula (IV) are shown below. The present invention is not limited to these.

(Other additives)
In addition to the rod-like liquid crystalline compound, the retardation film of this embodiment formed from the liquid crystal composition may optionally include a boronic acid compound represented by the general formula (I), a polymerizable initiator shown below, and an air interface vertical It is formed by applying a coating liquid (liquid crystal composition) containing other additives such as an alignment agent on an alignment film formed on a support, vertically aligning, and fixing the alignment state. be able to. When the retardation film of this embodiment is formed on a temporary support, it can also be produced by transferring the retardation film onto the support. Furthermore, not only the single-phase retardation film of the present aspect but also a plurality of retardation films can be laminated to form the second retardation film exhibiting the above-mentioned optical characteristics. In addition, the second retardation film may be configured so that the entire laminated body of the support and the retardation film of this aspect satisfies the above optical characteristics.

  In the retardation film of this embodiment, the vertically aligned rod-like liquid crystal compound is preferably fixed while maintaining the alignment state. The immobilization is preferably performed by a polymerization reaction of the polymerizable group (P) introduced into the rod-like liquid crystal compound. The polymerization reaction includes a thermal polymerization reaction using a thermal polymerization initiator and a photopolymerization reaction using a photopolymerization initiator, and a photopolymerization reaction is preferred. Examples of the photopolymerization initiator include α-carbonyl compounds (described in the specifications of US Pat. Nos. 2,367,661 and 2,367,670), acyloin ether (US Pat. No. 2,448,828). Description), α-hydrocarbon substituted aromatic acyloin compound (described in US Pat. No. 2,722,512), polynuclear quinone compound (US Pat. Nos. 3,046,127 and 2,951,758) Description), a combination of triarylimidazole dimer and p-aminophenyl ketone (described in US Pat. No. 3,549,367), acridine and phenazine compound (Japanese Patent Laid-Open No. 60-105667, US Pat. 239,850 description) and oxadiazole compounds (described in US Pat. No. 4,212,970).

The amount of the photopolymerization initiator used is preferably 0.01 to 20% by mass, more preferably 0.5 to 5% by mass, based on the solid content of the coating solution. Moreover, it is preferable to use ultraviolet rays for light irradiation for polymerization of the rod-like liquid crystalline molecules. The irradiation energy is preferably 20 mJ / cm ^{2 to} 50 J / cm ² , and more preferably 100 mJ / cm ^{2 to} 800 mJ / cm ² . Furthermore, in order to accelerate the photopolymerization reaction, light irradiation may be performed under heating conditions. The thickness of the retardation film of this embodiment including the optically anisotropic layer is preferably 0.1 to 10 μm, more preferably 0.5 to 5 μm, and most preferably 1 to 5 μm. preferable.

  Usually, since the liquid crystalline compound has a property of being inclined and aligned on the air interface side, it is necessary to control the alignment of the liquid crystalline compound vertically on the air interface side in order to obtain a uniformly vertically aligned state. . For this purpose, the liquid crystal composition contains a compound (air interface alignment agent) that is unevenly distributed on the air interface side and acts to vertically align the liquid crystalline compound by its excluded volume effect or electrostatic effect. The retardation film of this embodiment is preferably formed.

  As the air interface alignment agent, compounds described in JP-A Nos. 2002-20363 and 2002-129162 can be used. Also, paragraph numbers [0072] to [0075] of Japanese Patent Application Laid-Open No. 2004-053981, paragraph numbers [0071] to [0078] of Japanese Patent Application Laid-Open No. 2004-004688, and paragraph number [0052] of Japanese Patent Application Laid-Open No. 2004-139015. ] To [0054], [0065] to [0066], and [0092] to [0094] can be appropriately applied to the present invention. Furthermore, the following compounds can also be used.

  Moreover, the compound which has a fluoro aliphatic group and a hydrophilic group can also be used as an air interface side vertical alignment agent. Specifically, it is preferably a fluoropolymer having a fluoroaliphatic group and one or more hydrophilic groups, or a fluorine-containing compound represented by the following general formula (2).

<< Fluoropolymer >>
The fluoropolymer is selected from the group consisting of a fluoroaliphatic group, a carboxyl group (—COOH), a sulfo group (—SO ₃ H), a phosphonoxy group {—OP (═O) (OH) ₂ }, and salts thereof. A fluorine-based polymer having one or more hydrophilic groups can be used. The types of polymers are described in “Revised Chemistry of Polymer Synthesis” (Takayuki Otsu, published by Kagaku Dojin Co., 1968), pages 1-4, for example, polyolefins, polyesters, polyamides, polyimides. , Polyurethanes, polycarbonates, polysulfones, polycarbonates, polyethers, polyacetals, polyketones, polyphenylene oxides, polyphenylene sulfides, polyarylates, PTFEs, polyvinylidene fluorides, cellulose derivatives, etc. It is done. The fluoropolymer is preferably a polyolefin.

  The fluorine-based polymer is a polymer having a fluoroaliphatic group in the side chain. The fluoroaliphatic group preferably has 1 to 12 carbon atoms, and more preferably 6 to 10 carbon atoms. The aliphatic group may be linear or cyclic, and when it is linear, it may be linear or branched. Of these, a linear fluoroaliphatic group having 6 to 10 carbon atoms is preferable. The degree of substitution with fluorine atoms is not particularly limited, but 50% or more of hydrogen atoms in the aliphatic group are preferably substituted with fluorine atoms, and more preferably 60% or more are substituted. The fluoroaliphatic group is contained in a side chain bonded to the polymer main chain via an ester bond, an amide bond, an imide bond, a urethane bond, a urea bond, an ether bond, a thioether bond, an aromatic ring, or the like. One of the fluoroaliphatic groups is derived from a fluoroaliphatic compound produced by a telomerization method (also referred to as a telomer method) or an oligomerization method (also referred to as an oligomer method). Regarding the production method of these fluoroaliphatic compounds, for example, “Synthesis and Function of Fluorine Compounds” (Supervision: Nobuo Ishikawa, Issue: CMC Co., 1987), “Chemistry of Organic Fluorines Compounds”. II "(Monograph 187, Ed by Milos Hudricky and Attila E. Pavlath, American Chemical Society 1995). The telomerization method is a method of synthesizing a telomer by radical polymerization of a fluorine-containing vinyl compound such as tetrafluoroethylene using an alkyl halide having a large chain transfer constant such as iodide as a telogen (an example is shown in Scheme 1). )

  The obtained terminal iodinated telomer is usually subjected to appropriate terminal chemical modification such as [Scheme 2], and led to a fluoroaliphatic compound. These compounds are further converted into a desired monomer structure as necessary, and used for the production of a fluoroaliphatic group-containing polymer.

  Specific examples of the fluoroaliphatic group-containing monomer that can be used in the production of the fluoropolymer that can be used in the present invention are listed below, but the compounds that can be used in the present invention are not limited in any way by the following specific examples. Absent.

  One aspect of the fluoropolymer usable in the present invention is a copolymer having a repeating unit derived from a fluoroaliphatic group-containing monomer and a repeating unit containing a hydrophilic group represented by the following general formula (1). It is a polymer.

In the general formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent. Q represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a phosphonoxy group {—OP (═O) (OH) ₂ } or a salt thereof. L represents an arbitrary group selected from the following linking group group, or a divalent linking group formed by combining two or more thereof.
(Linked group group)
Single bond, —O—, —CO—, —NR ⁴ — (R ⁴ represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group), —S—, —SO ₂ —, —P (═O) (OR ⁵ ) — (R ⁵ represents an alkyl group, an aryl group, or an aralkyl group), an alkylene group, and an arylene group.

In general formula (1), R ¹ , R ² and R ³ each independently represent a hydrogen atom or a substituent selected from the following substituent group Y.
(Substituent group Y)
An alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, such as a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group and the like, alkenyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, Particularly preferred is an alkenyl group having 2 to 8 carbon atoms, such as vinyl group, allyl group, 2-butenyl group, 3-pentenyl group and the like, and alkynyl group (preferably having 2 to 20 carbon atoms, more preferably Is an alkynyl group having 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, and examples thereof include a propargyl group and a 3-pentynyl group. An aryl group (preferably an aryl group having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 12 carbon atoms, such as a phenyl group, a p-methylphenyl group, and a naphthyl group. Aralkyl groups (preferably 7 to 30 carbon atoms, more preferably 7 to 20 carbon atoms, particularly preferably 7 to 12 carbon atoms, such as benzyl group, phenethyl group, 3- Phenylpropyl group and the like), a substituted or unsubstituted amino group (preferably an amino group having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, particularly preferably 0 to 6 carbon atoms, Unsubstituted amino group, methylamino group, dimethylamino group, diethylamino group, anilino group, etc.),

An alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 10 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a butoxy group). An alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms such as a methoxycarbonyl group and an ethoxycarbonyl group), acyloxy A group (preferably an acyloxy group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms such as an acetoxy group and a benzoyloxy group), an acylamino group (preferably 2-20 carbon atoms, more preferably 2-16 carbon atoms, particularly preferably 2-10 carbon atoms. A silamino group, for example, an acetylamino group, a benzoylamino group, and the like, an alkoxycarbonylamino group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, and particularly preferably 2 to 12 carbon atoms). An alkoxycarbonylamino group, for example, a methoxycarbonylamino group), an aryloxycarbonylamino group (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, and particularly preferably 7 to 12 carbon atoms). Aryloxycarbonylamino group, for example, phenyloxycarbonylamino group and the like, sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 1 carbon atoms). 12 sulfonylamino groups such as methanesulfonyl And sulfamoyl groups (preferably having 0 to 20 carbon atoms, more preferably 0 to 16 carbon atoms, and particularly preferably 0 to 12 carbon atoms, such as sulfamoyl group). Group, methylsulfamoyl group, dimethylsulfamoyl group, phenylsulfamoyl group and the like), carbamoyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably carbon number). 1 to 12 carbamoyl groups, for example, unsubstituted carbamoyl group, methylcarbamoyl group, diethylcarbamoyl group, phenylcarbamoyl group and the like),

An alkylthio group (preferably an alkylthio group having 1 to 20 carbon atoms, more preferably an alkylthio group having 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as a methylthio group and an ethylthio group), an arylthio group ( Preferably it is C6-C20, More preferably, it is C6-C16, Most preferably, it is C6-C12 arylthio group, for example, a phenylthio group etc. are mentioned, A sulfonyl group (preferably C1-C1). 20, more preferably a sulfonyl group having 1 to 16 carbon atoms, particularly preferably a sulfonyl group having 1 to 12 carbon atoms, such as a mesyl group and a tosyl group, and a sulfinyl group (preferably having a carbon number of 1 to 20, more A sulfinyl group having 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms is preferable. Zensulfinyl group and the like), ureido group (preferably a ureido group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, for example, an unsubstituted ureido group , Methylureido group, phenylureido group, etc.), phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 16 carbon atoms, particularly preferably having 1 to 12 carbon atoms). Yes, for example, diethyl phosphoric acid amide group, phenyl phosphoric acid amide group, etc.), hydroxy group, mercapto group, halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, Carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, heterocyclic group (preferably having a carbon number of 1 to 0, more preferably a heterocyclic group of 1 to 12, for example, a heterocyclic group having a heteroatom such as a nitrogen atom, an oxygen atom, a sulfur atom, such as an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group , Piperidyl group, morpholino group, benzoxazolyl group, benzimidazolyl group, benzthiazolyl group and the like), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably A silyl group having 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group and a triphenylsilyl group). These substituents may be further substituted with these substituents. Moreover, when it has two or more substituents, they may be the same or different. If possible, they may be bonded to each other to form a ring.

R ¹ , R ² and R ³ are each independently a hydrogen atom, an alkyl group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), or a group represented by -LQ described later. It is preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a chlorine atom, or a group represented by -LQ, more preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Particularly preferred are a hydrogen atom and an alkyl group having 1 to 2 carbon atoms. Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group, n-butyl group, sec-butyl group and the like. The alkyl group may have a suitable substituent. Examples of the substituent include a halogen atom, aryl group, heterocyclic group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, acyl group, hydroxyl group, acyloxy group, amino group, alkoxycarbonyl group, acylamino group, oxycarbonyl Group, carbamoyl group, sulfonyl group, sulfamoyl group, sulfonamido group, sulfolyl group, carboxyl group and the like. The carbon number of the alkyl group does not include the carbon atom of the substituent. The same applies to the carbon number of other groups.

L represents a divalent linking group selected from the above linking group group, or a divalent linking group formed by combining two or more thereof. In the linking group group, R ^{4 in} —NR ⁴ — represents a hydrogen atom, an alkyl group, an aryl group or an aralkyl group, preferably a hydrogen atom or an alkyl group. R ⁵ in —PO (OR ⁵ ) — represents an alkyl group, an aryl group or an aralkyl group, and preferably an alkyl group. When R ⁴ and R ⁵ represent an alkyl group, an aryl group or an aralkyl group, the preferred range of the carbon number is the same as that described in “Substituent group Y”. L preferably contains a single bond, —O—, —CO—, —NR ⁴ —, —S—, —SO ₂ —, an alkylene group or an arylene group, and —CO—, —O—, —NR ⁴ -, and more preferably contains an alkylene group or an arylene group. When L contains an alkylene group, the alkylene group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 6 carbon atoms.
Specific examples of particularly preferred alkylene groups include methylene, ethylene, trimethylene, tetrabutylene, hexamethylene groups and the like. When L contains an arylene group, the carbon number of the arylene group is preferably 6 to 24, more preferably 6 to 18, and particularly preferably 6 to 12. Specific examples of particularly preferred arylene groups include phenylene and naphthalene groups. When L contains a divalent linking group (that is, an aralkylene group) obtained by combining an alkylene group and an arylene group, the carbon number of the aralkylene group is preferably 7 to 34, more preferably 7 to 26, and particularly preferably. 7-16. Specific examples of particularly preferred aralkylene groups include a phenylenemethylene group, a phenyleneethylene group, and a methylenephenylene group. The group listed as L may have a suitable substituent. Examples of such a substituent include those similar to the substituents exemplified above as the substituents for R ^{1 to} R ³ .

  Specific examples of L are shown below, but L that can be employed in the present invention is not limited to these specific examples.

  In the formula (1), Q is a carboxyl group, a salt of a carboxyl group (for example, lithium salt, sodium salt, potassium salt, ammonium salt (for example, ammonium, tetramethylammonium, trimethyl-2-hydroxyethylammonium, tetrabutylammonium, trimethyl). Benzylammonium, dimethylphenylammonium, etc.), pyridinium salts, etc.), sulfo groups, salts of sulfo groups (examples of cations forming salts are the same as those described above for carboxyl groups), phosphonoxy groups, salts of phosphonoxy groups (salts) Examples of the cation that forms are the same as those described above for the carboxyl group). A carboxyl group, a sulfo group, and a phospho group are more preferable, and a carboxyl group or a sulfo group is particularly preferable.

  The fluoropolymer may contain one type of repeating unit represented by the general formula (1) or two or more types. Moreover, the said fluorine-type polymer may have 1 type (s) or 2 or more types of repeating units other than said each repeating unit. The other repeating units are not particularly limited, and preferred examples thereof include repeating units derived from ordinary radical polymerizable monomers. Hereinafter, specific examples of monomers for deriving other repeating units will be given. The fluoropolymer may contain a repeating unit derived from one or more monomers selected from the following monomer group.

Monomer group (1) Alkenes ethylene, propylene, 1-butene, isobutene, 1-hexene, 1-dodecene, 1-octadecene, 1-eicosene, hexafluoropropene, vinylidene fluoride, chlorotrifluoroethylene, 3, 3, 3-trifluoropropylene, tetrafluoroethylene, vinyl chloride, vinylidene chloride, etc .;
(2) Dienes 1,3-butadiene, isoprene, 1,3-pentadiene, 2-ethyl-1,3-butadiene, 2-n-propyl-1,3-butadiene, 2,3-dimethyl-1,3 -Butadiene, 2-methyl-1,3-pentadiene, 1-phenyl-1,3-butadiene, 1-α-naphthyl-1,3-butadiene, 1-β-naphthyl-1,3-butadiene, 2-chloro -1,3-butadiene, 1-bromo-1,3-butadiene, 1-chlorobutadiene, 2-fluoro-1,3-butadiene, 2,3-dichloro-1,3-butadiene, 1,1,2- Trichloro-1,3-butadiene and 2-cyano-1,3-butadiene, 1,4-divinylcyclohexane and the like;

(3) Derivatives of α, β-unsaturated carboxylic acid (3a) Alkyl acrylates Methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate , Amyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, tert-octyl acrylate, dodecyl acrylate, phenyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, 2-bromoethyl acrylate, 4-chlorobutyl acrylate, 2-cyanoethyl acrylate, 2-acetoxyethyl acrylate, methoxybenzyl Chryrate, 2-chlorocyclohexyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, 2-methoxyethyl acrylate, ω-methoxypolyethylene glycol acrylate (number of added polyoxyethylene: n = 2 to 100), 3-methoxy Butyl acrylate, 2-ethoxyethyl acrylate, 2-butoxyethyl acrylate, 2- (2-butoxyethoxy) ethyl acrylate, 1-bromo-2-methoxyethyl acrylate, 1,1-dichloro-2-ethoxyethyl acrylate, glycidyl acrylate Such);

(3b) Alkyl methacrylates Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, amyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2 -Ethylhexyl methacrylate, n-octyl methacrylate, stearyl methacrylate, benzyl methacrylate, phenyl methacrylate, allyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, cresyl methacrylate, naphthyl methacrylate, 2-methoxyethyl methacrylate, 3-methoxybutyl methacrylate, ω Methoxypolyethylene glycol methacrylate (number of added polyoxyethylene: n = 2 to 100), 2-acetoxyethyl methacrylate, 2-ethoxyethyl methacrylate, 2-butoxyethyl methacrylate, 2- (2-butoxyethoxy) ethyl methacrylate Glycidyl methacrylate, 3-trimethoxysilylpropyl methacrylate, allyl methacrylate, 2-isocyanatoethyl methacrylate, etc .;

(3c) Diesters of unsaturated polycarboxylic acids Dimethyl maleate, dibutyl maleate, dimethyl itaconate, dibutyl taconate, dibutyl crotonate, dihexyl crotonate, diethyl fumarate, dimethyl fumarate, etc .;

(3d) Amides of α, β-unsaturated carboxylic acids N, N-dimethylacrylamide, N, N-diethylacrylamide, Nn-propylacrylamide, N-tertbutylacrylamide, N-tertoctylmethacrylamide, N- Cyclohexylacrylamide, N-phenylacrylamide, N- (2-acetoacetoxyethyl) acrylamide, N-benzylacrylamide, N-acryloylmorpholine, diacetone acrylamide, N-methylmaleimide and the like;

(4) Unsaturated nitriles Acrylonitrile, methacrylonitrile, etc .;
(5) Styrene and its derivatives Styrene, vinyl toluene, ethyl styrene, p-tert butyl styrene, methyl p-vinyl benzoate, α-methyl styrene, p-chloromethyl styrene, vinyl naphthalene, p-methoxy styrene, p-hydroxy Methyl styrene, p-acetoxy styrene, etc .;
(6) Vinyl esters Vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl benzoate, vinyl salicylate, vinyl chloroacetate, vinyl methoxyacetate, vinyl vinyl acetate, etc .;

(7) Vinyl ethers Methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-octyl vinyl ether, n-dodecyl Vinyl ether, n-eicosyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, fluorobutyl vinyl ether, fluorobutoxyethyl vinyl ether, etc .; and (8) other polymerizable monomers N-vinyl pyrrolidone, methyl vinyl ketone, phenyl vinyl ketone, Methoxyethyl vinyl ketone, 2-vinyl oxazoline, 2-isopropenyl oxazoline, etc.

  In the fluoropolymer, the amount of the fluoroaliphatic group-containing monomer is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 30% by mass or more of the total amount of constituent monomers of the polymer. Is more preferable. In the fluoropolymer, the amount of the repeating unit represented by the general formula (1) is preferably 0.5% by mass or more, and 1 to 20% by mass of the total amount of the constituent monomers of the fluoropolymer. Is more preferable, and it is further more preferable that it is 1-10 mass%. Since the above-mentioned mass percentage easily varies in a preferable range depending on the molecular weight of the monomer used, the content of the repeating unit represented by the general formula (1) is expressed by the number of moles of the functional group per unit mass of the polymer. Can be accurately defined. When this notation is used, the preferable amount of the hydrophilic group (Q in the formula (1)) contained in the fluoropolymer is 0.1 mmol / g to 10 mmol / g, and the more preferable amount is 0. .2 mmol / g to 8 mmol / g.

  The fluorine-based polymer used in the present invention preferably has a mass average molecular weight of 1,000,000 or less, more preferably 500,000 or less, and even more preferably 100,000 or less. The mass average molecular weight can be measured as a value in terms of polystyrene (PS) using gel permeation chromatography (GPC).

  The manufacturing method of the said fluorine-type polymer is not specifically limited, It can manufacture by a well-known and usual method. For example, it can be produced by adding a general-purpose radical polymerization initiator to an organic solvent containing the above-described monomer having a fluoroaliphatic group, a monomer having a hydrogen bonding group, and the like, and polymerizing the mixture. Further, in some cases, other addition-polymerizable unsaturated compounds can be further added and produced by the same method as described above. Depending on the polymerizability of each monomer, a dropping polymerization method in which a monomer and an initiator are added dropwise to a reaction vessel is also effective for obtaining a polymer having a uniform composition. For example, a polymerization method such as cationic polymerization, radical polymerization, or anionic polymerization using a vinyl group can be employed, and among these, radical polymerization is particularly preferable because it can be used for general purposes. As the polymerization initiator for radical polymerization, known compounds such as radical thermal polymerization initiators and radical photopolymerization initiators can be used, and it is particularly preferable to use radical thermal polymerization initiators. Here, the radical thermal polymerization initiator is a compound that generates radicals by heating to a decomposition temperature or higher. Examples of such radical thermal polymerization initiators include diacyl peroxide (acetyl peroxide, benzoyl peroxide, etc.), ketone peroxide (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), hydroperoxide (hydrogen peroxide, tert. -Butyl hydroxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyesters (tert-butyl peroxyacetate, tert) -Butyl peroxypivalate, etc.), azo compounds (azobisisobutyronitrile, azobisisovaleronitrile, etc.), persulfates (ammonium persulfate, sodium persulfate) And potassium persulfate) and the like. Such radical thermal polymerization initiators can be used singly or in combination of two or more.

  The radical polymerization method is not particularly limited, and an emulsion polymerization method, a suspension polymerization method, a bulk polymerization method, a solution polymerization method, and the like can be adopted. The solution polymerization, which is a typical radical polymerization method, will be described more specifically. The outlines of other polymerization methods are the same, and details thereof are described, for example, in “Polymer Science Experimental Method” edited by Polymer Society (Tokyo Kagaku Dojin, 1981).

  An organic solvent is used for solution polymerization. These organic solvents can be arbitrarily selected within a range that does not impair the purpose and effect of this embodiment. These organic solvents are usually organic compounds having boiling points under atmospheric pressure in the range of 50 to 200 ° C., and organic compounds that uniformly dissolve each component are preferred. Examples of preferred organic solvents include alcohols such as isopropanol and butanol; ethers such as dibutyl ether, ethylene glycol dimethyl ether, tetrahydrofuran and dioxane; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ethyl acetate and acetic acid And esters such as butyl, amyl acetate, and γ-butyrolactone; and aromatic hydrocarbons such as benzene, toluene, and xylene. In addition, these organic solvents can be used individually by 1 type or in combination of 2 or more types. Furthermore, a water-mixed organic solvent in which water is used in combination with the above organic solvent is also applicable from the viewpoint of the solubility of the monomer and the polymer to be produced.

  Also, the solution polymerization conditions are not particularly limited, but for example, it is preferable to heat within a temperature range of 50 to 200 ° C. for 10 minutes to 30 hours. Furthermore, in order not to deactivate the generated radicals, it is preferable to perform an inert gas purge not only during solution polymerization but also before the start of solution polymerization. Usually, nitrogen gas is suitably used as the inert gas.

  In order to obtain the fluoropolymer in a preferable molecular weight range, a radical polymerization method using a chain transfer agent is particularly effective. As chain transfer agents, mercaptans (for example, octyl mercaptan, decyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, octadecyl mercaptan, thiophenol, p-nonylthiophenol, etc.), polyhalogenated alkyls (for example, carbon tetrachloride, chloroform, etc.) , 1,1,1-trichloroethane, 1,1,1-tribromooctane, etc.) and low-activity monomers (α-methylstyrene, α-methylstyrene dimer, etc.) can be used, preferably carbon These are mercaptans of 4-16. The amount of these chain transfer agents used is remarkably influenced by the activity of the chain transfer agent, the combination of the monomers, the polymerization conditions and the like, and must be precisely controlled. It is about 01 mol% to 50 mol%, preferably 0.05 mol% to 30 mol%, particularly preferably 0.08 mol% to 25 mol%. These chain transfer agents may be present in the system simultaneously with the target monomer whose degree of polymerization is to be controlled in the polymerization process, and the addition method is not particularly limited. It may be added after being dissolved in the monomer, or may be added separately from the monomer.

  As described above, the fluorine-based polymer preferably has a polymerizable group as a substituent in order to fix the alignment state of molecules of a liquid crystal compound, particularly a discotic liquid crystal compound.

  Specific examples of the fluoroaliphatic group-containing copolymer preferably used in the present invention as the fluorine-based polymer are shown below, but the present invention is not limited to these specific examples. Here, the numerical values (numerical values such as a, b, c, and d) in the formula are mass percentages indicating the composition ratio of each monomer, and Mw is a mass average molecular weight in terms of PS measured by GPC.

  The preferred range of the content of the fluoropolymer in the composition varies depending on the application, but when used for forming the optically anisotropic layer, the composition (a composition excluding the solvent in the case of a coating solution) Among these, 0.005 to 8% by mass is preferable, 0.01 to 5% by mass is more preferable, and 0.05 to 1% by mass is even more preferable. If the addition amount of the fluorine-based polymer is less than 0.005% by mass, the effect is insufficient, and if it exceeds 8% by mass, the coating film cannot be sufficiently dried, or the performance as an optical film (for example, letter The uniformity of the foundation).

<< Fluorine-containing compound represented by formula (2) >>
Next, the fluorine-containing compound represented by the general formula (2) will be described.
General formula (2)
(R ⁰ ) _m −L ⁰ − (W) _n
In the formula, R ⁰ represents an alkyl group, an alkyl group having a CF ₃ group at the terminal, or an alkyl group having a CF ₂ H group at the terminal, and m represents an integer of 1 or more. A plurality of R ⁰ may be the same or different, but at least one represents an alkyl group having a CF ₃ group or a CF ₂ H group at the terminal.
L ⁰ represents an (m + n) -valent linking group, W represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or a salt thereof, or A phosphonoxy group {—OP (═O) (OH) ₂ } or a salt thereof is represented, and n represents an integer of 1 or more.

In Formula (2), R ⁰ functions as a hydrophobic group of the fluorine-containing compound. The alkyl group represented by R ⁰ is a substituted or unsubstituted alkyl group, which may be linear or branched, preferably an alkyl group having 1 to 20 carbon atoms, more preferably Is an alkyl group of 4 to 16, particularly preferably an alkyl group of 6 to 16. As the substituent, any of the substituents exemplified as the substituent group D described later can be applied.

The alkyl group having a CF ₃ group at the terminal represented by R ⁰ preferably has 1 to 20 carbon atoms, more preferably 4 to 16 and particularly preferably 4 to 8. The alkyl group having a CF ₃ group at the terminal is an alkyl group in which part or all of the hydrogen atoms contained in the alkyl group are substituted with fluorine atoms. 50% or more of the hydrogen atoms in the alkyl group are preferably substituted with fluorine atoms, more preferably 60% or more are substituted, and particularly preferably 70% or more are substituted. The remaining hydrogen atoms may be further substituted with the substituents exemplified as the substituent group D described later. The alkyl group having a CF ₂ H group at the terminal represented by R ⁰ preferably has 1 to 20 carbon atoms, more preferably 4 to 16 and particularly preferably 4 to 8. The alkyl group having a CF ₂ H group at the terminal is an alkyl group in which some or all of the hydrogen atoms contained in the alkyl group are substituted with fluorine atoms. 50% or more of hydrogen atoms in the alkyl group are preferably substituted with fluorine atoms, more preferably 60% or more are substituted, and particularly preferably 70% or more are substituted. The remaining hydrogen atoms may be further substituted with the substituents exemplified as the substituent group D described later. Examples of an alkyl group having a CF ₃ group at the terminal represented by R ⁰ or an alkyl group having a CF ₂ H group at the terminal are shown below.

R1: n-C ₈ F _{17-
R2: n-C 6 F 13} -
_{R3: n-C 4 F 9} -
_{R4: n-C 8 F 17} - (CH 2) 2 -
_{R5: n-C 6 F 13} - (CH 2) 2 -
_{R6: n-C 4 F 9} - (CH 2) 2 -
_{R7: H- (CF 2) 8} -
_{R8: H- (CF 2) 6} -
_{R9: H- (CF 2) 4} -
_{R10: H- (CF 2) 8} - (CH 2) -
R11: H— (CF ₂ ) ₆ — (CH ₂ ) —
_{R12: H- (CF 2) 4} - (CH 2) -

In the formula (2), the (m + n) -valent linking group represented by L ⁰ is an alkylene group, an alkenylene group, an aromatic group, a heterocyclic group, —CO—, or —NR— (R has 1 carbon atom. A linking group in which at least two groups selected from the group consisting of —O—, —S—, —SO—, and —SO ₂ — are combined.

In the formula (2), W represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or a salt thereof, or a phosphonoxy group {—OP (= O) (OH) ₂ } or a salt thereof. The preferable range of W is the same as Q in the general formula (1).

  Among the fluorine-containing compounds represented by the general formula (2), a compound represented by the following general formula (2a) or a general formula (2b) described later is preferable.

In formula (2a), R ⁵ and R ⁶ each represents an alkyl group, an alkyl group having a CF ₃ group at the terminal, or an alkyl group having a CF ₂ H group at the terminal, wherein R ⁵ and R ⁶ are simultaneously an alkyl group. Never. W ¹ and W ² are each a hydrogen atom, a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or a salt thereof, a phosphonoxy group {—OP ( ═O) (OH) ₂ } or a salt thereof, or an alkyl group, an alkoxy group or an alkylamino group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent, wherein W ¹ and W ² are simultaneously It is not a hydrogen atom.

R ⁵ and R ⁶ have the same meaning as R ⁰ in the general formula (2), and their preferred ranges are also the same. Carboxyl group (—COOH) or a salt thereof represented by W ¹ and W ² , sulfo group (—SO ₃ H) or a salt thereof, sulfato group (—OSO ₃ H) or a salt thereof, phosphonoxy group {—OP (= O) (OH) ₂ } or a salt thereof is synonymous with W in the general formula (2), and its preferred range is also the same. The alkyl group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent represented by W ¹ and W ² may be linear or branched, and preferably has 1 carbon atom. -20 alkyl groups, more preferably 1-8 alkyl groups, and particularly preferably 1-3 alkyl groups. The alkyl group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group as the substituent may have at least one carboxyl group, sulfo group, sulfato group, or phosphonoxy group. The group and the phosphonoxy group are synonymous with the carboxyl group, the sulfo group, the sulfato group, and the phosphonoxy group represented by W in the general formula (2), and the preferred range is also the same. The alkyl group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as the substituent may be substituted with a substituent other than this, and the substituent is exemplified as the substituent group D described later. Either of these can be applied. The alkoxy group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent represented by W ¹ and W ² may be linear or branched, and preferably has 1 carbon atom. -20 alkoxy groups, more preferably 1-8 alkoxy groups, and particularly preferably 1-4 alkoxy groups. The alkoxy group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as the substituent may have at least one carboxyl group, sulfo group, sulfato group or phosphonoxy group. The group and the phosphonoxy group are synonymous with the carboxyl group, the sulfo group, the sulfato group, and the phosphonoxy group represented by W in the general formula (2), and the preferred range is also the same. The alkoxy group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group may be substituted with a substituent other than this, and the substituent is any of the substituents exemplified as Substituent Group D described later. Can be applied. The alkylamino group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent represented by W ¹ and W ² may be linear or branched, and preferably has a carbon number. 1 to 20 alkylamino groups, more preferably 1 to 8 alkylamino groups, and particularly preferably 1 to 4 alkylamino groups. The alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group may have at least one carboxyl group, sulfo group, sulfato group, or phosphonoxy group, such as a carboxyl group, a sulfo group, a sulfato group, and The phosphonoxy group is synonymous with the carboxyl group, sulfo group, sulfato group and phosphonoxy group represented by W in the general formula (2), and the preferred range is also the same. The alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group may be substituted with other substituents, and any of the substituents exemplified as Substituent Group D described later can be used as the substituent. Can apply.

W ¹ and W ² are particularly preferably each a hydrogen atom or (CH ₂ ) _n SO ₃ M (n represents 0 or 1). M represents a cation, but M may not be present when the charge is 0 in the molecule. As cations represented by M, for example, protonium ions, alkali metal ions (lithium ions, sodium ions, potassium ions, etc.), alkaline earth metal ions (barium ions, calcium ions, etc.), ammonium ions and the like are preferably applied. . Of these, proton ions, lithium ions, sodium ions, potassium ions, and ammonium ions are particularly preferable.

Next, the following general formula (2b) will be described.
General formula (2b)
(R ⁷ -L ^1- ) _m2 (Ar ¹ ) -W ³
In the formula (2b), R ⁷ represents an alkyl group, an alkyl group having a CF ₃ group at the terminal, or an alkyl group having a CF ₂ H group at the terminal, m2 represents an integer of 1 or more, and a plurality of R ⁷ May be the same or different, but at least one represents an alkyl group having a CF ₃ group or a CF ₂ H group at the terminal. L ¹ is an alkylene group, an aromatic group, —CO—, —NR— (R is an alkyl group having 1 to 5 carbon atoms or a hydrogen atom), —O—, —S—, —SO—, —SO. _2- represents a divalent linking group selected from the group consisting of a combination thereof, and a plurality of L ¹ may be the same or different. Ar ¹ represents an aromatic hydrocarbon ring or an aromatic heterocycle, W ³ represents a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, a sulfato group (—OSO ₃ H) or A salt thereof, a phosphonoxy group {—OP (═O) (OH) ₂ } or a salt thereof, or an alkyl group, an alkoxy group, or an alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group as a substituent. .

R ⁷ has the same meaning as R ⁰ in formula (2), and its preferred range is also the same. L ¹ is preferably an alkylene group having 1 to 12 carbon atoms, an aromatic group having 6 to 12 carbon atoms, —CO—, —NR—, —O—, —S—, —SO—, —SO ₂ — and Represents a linking group having a total carbon number of 0 to 40 consisting of a combination thereof, particularly preferably an alkylene group having 1 to 8 carbon atoms, a phenyl group, —CO—, —NR—, —O—, —S—, —SO. ₂ represents a linking group having 0 to 20 carbon atoms and a combination thereof. Ar ¹ preferably represents an aromatic hydrocarbon ring having 6 to 12 carbon atoms, particularly preferably a benzene ring or a naphthalene ring. Carboxyl group represented by W ³ (—COOH) or a salt thereof, sulfo group (—SO ₃ H) or a salt thereof, sulfato group (—OSO ₃ H) or a salt thereof, phosphonoxy group {—OP (═O) ( OH) ₂ } or a salt thereof, or an alkyl group, an alkoxy group, or an alkylamino group having a carboxyl group, a sulfo group, a sulfato group, or a phosphonoxy group as a substituent, as W ¹ and W ² in the general formula (2a). Carboxyl group (—COOH) or a salt thereof, sulfo group (—SO ₃ H) or a salt thereof, sulfato group (—OSO ₃ H) or a salt thereof, phosphonoxy group {—OP (═O) (OH) ₂ } Or a salt thereof, an alkyl group having a carboxyl group, a sulfo group, a sulfato group or a phosphonoxy group as a substituent, an alkoxy group Group, or has the same meaning as the alkylamino group and the preferable ranges thereof are the same.

W ³ is preferably a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or a salt thereof, or a carboxyl group (—COOH) or a salt thereof or a sulfo group (—SO ₃ H) as a substituent. Alternatively, it is an alkylamino group having a salt thereof, and particularly preferably SO ₃ M or CO ₂ M. M represents a cation, but M may not be present when the charge is 0 in the molecule. As cations represented by M, for example, protonium ions, alkali metal ions (lithium ions, sodium ions, potassium ions, etc.), alkaline earth metal ions (barium ions, calcium ions, etc.), ammonium ions and the like are preferably applied. . Of these, proton ions, lithium ions, sodium ions, potassium ions, and ammonium ions are particularly preferable.

  In the present specification, the substituent group D includes an alkyl group (preferably an alkyl group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, and particularly preferably 1 to 8 carbon atoms, such as a methyl group. , Ethyl group, isopropyl group, tert-butyl group, n-octyl group, n-decyl group, n-hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (preferably having 2 carbon atoms) -20, more preferably an alkenyl group having 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, and examples thereof include a vinyl group, an allyl group, a 2-butenyl group, and a 3-pentenyl group), alkynyl A group (preferably an alkynyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, particularly preferably 2 to 8 carbon atoms, And aryl groups (preferably having 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, and particularly preferably 6 to 12 carbon atoms). For example, phenyl Group, p-methylphenyl group, naphthyl group and the like), substituted or unsubstituted amino group (preferably having 0 to 20 carbon atoms, more preferably 0 to 10 carbon atoms, and particularly preferably 0 to 6 carbon atoms). An amino group, for example, an unsubstituted amino group, a methylamino group, a dimethylamino group, a diethylamino group, a dibenzylamino group and the like),

An alkoxy group (preferably an alkoxy group having 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, particularly preferably 1 to 8 carbon atoms, and examples thereof include a methoxy group, an ethoxy group, and a butoxy group). An aryloxy group (preferably an aryloxy group having 6 to 20 carbon atoms, more preferably 6 to 16 carbon atoms, particularly preferably 6 to 12 carbon atoms, and examples thereof include a phenyloxy group and a 2-naphthyloxy group. An acyl group (preferably having a carbon number of 1-20, more preferably a carbon number of 1-16, particularly preferably a carbon number of 1-12, such as an acetyl group, a benzoyl group, a formyl group, a pivaloyl group, etc. An alkoxycarbonyl group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, and particularly preferably 2 to 2 carbon atoms). 2 alkoxycarbonyl groups, for example, methoxycarbonyl group, ethoxycarbonyl group and the like, and aryloxycarbonyl groups (preferably having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, and particularly preferably carbon numbers). An aryloxycarbonyl group having 7 to 10 carbon atoms, such as a phenyloxycarbonyl group, an acyloxy group (preferably having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, and particularly preferably 2 to 2 carbon atoms). 10 acyloxy groups such as an acetoxy group and a benzoyloxy group)

An acylamino group (preferably an acylamino group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 10 carbon atoms, such as an acetylamino group and a benzoylamino group), alkoxycarbonyl An amino group (preferably an alkoxycarbonylamino group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as a methoxycarbonylamino group), aryloxy Carbonylamino group (preferably an aryloxycarbonylamino group having 7 to 20 carbon atoms, more preferably 7 to 16 carbon atoms, particularly preferably 7 to 12 carbon atoms, such as a phenyloxycarbonylamino group) Sulfonylamino group (preferably having 1 to 20 carbon atoms, more preferred Or a sulfonylamino group having 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include a methanesulfonylamino group and a benzenesulfonylamino group, and a sulfamoyl group (preferably having a carbon number of 0 to 20). More preferably, it is a sulfamoyl group having 0 to 16 carbon atoms, particularly preferably 0 to 12 carbon atoms, and examples thereof include a sulfamoyl group, a methylsulfamoyl group, a dimethylsulfamoyl group, and a phenylsulfamoyl group. ), A carbamoyl group (preferably a carbamoyl group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably 1 to 12 carbon atoms. For example, an unsubstituted carbamoyl group, a methylcarbamoyl group, diethylcarbamoyl group Group, phenylcarbamoyl group, etc.),

An alkylthio group (preferably an alkylthio group having 1 to 20 carbon atoms, more preferably an alkylthio group having 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as a methylthio group and an ethylthio group), an arylthio group ( Preferably it is C6-C20, More preferably, it is C6-C16, Most preferably, it is C6-C12 arylthio group, for example, a phenylthio group etc. are mentioned, A sulfonyl group (preferably C1-C1). 20, more preferably a sulfonyl group having 1 to 16 carbon atoms, particularly preferably a sulfonyl group having 1 to 12 carbon atoms, such as a mesyl group and a tosyl group, and a sulfinyl group (preferably having a carbon number of 1 to 20, more A sulfinyl group having 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms is preferable. Zensulfinyl group and the like), ureido group (preferably a ureido group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, for example, an unsubstituted ureido group , Methylureido group, phenylureido group, etc.), phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably having 1 to 16 carbon atoms, particularly preferably having 1 to 12 carbon atoms). Yes, for example, diethyl phosphoric acid amide group, phenyl phosphoric acid amide group, etc.), hydroxy group, mercapto group, halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, sulfo group, Carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, heterocyclic group (preferably having a carbon number of 1 to 0, more preferably a heterocyclic group of 1 to 12, for example, a heterocyclic group having a heteroatom such as a nitrogen atom, an oxygen atom, a sulfur atom, such as an imidazolyl group, a pyridyl group, a quinolyl group, a furyl group , Piperidyl group, morpholino group, benzoxazolyl group, benzimidazolyl group, benzthiazolyl group and the like), silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably A silyl group having 3 to 24 carbon atoms, and examples thereof include a trimethylsilyl group and a triphenylsilyl group). These substituents may be further substituted with these substituents. Further, when two or more substituents are present, they may be the same or different. If possible, they may be bonded to each other to form a ring.

  In addition, the said fluorine-containing compound has a polymeric group as a substituent in order to fix the orientation state of the molecule | numerator of a liquid crystalline compound, especially a discotic liquid crystalline compound.

  Specific examples of the fluorine-containing compound represented by the general formula (2) that can be used in the present invention are shown below, but the fluorine-containing compound used in the present invention is not limited thereto. In the following specific examples, no. IV-1 to 42 are general formula (2a), No. IV-43 to 66 are examples of the compound represented by the general formula (2b).

[Preparation of retardation film]
The retardation film of this embodiment can be prepared, for example, by applying a coating solution and drying it.
(solvent)
An organic solvent is preferably used as a solvent used for preparing the coating liquid such as the liquid crystal composition. Examples of the organic solvent include amide (eg, N, N-dimethylformamide), sulfoxide (eg, dimethyl sulfoxide), heterocyclic compound (eg, pyridine), hydrocarbon (eg, benzene, hexane), alkyl halide ( Examples, chloroform, dichloromethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane) are included. Alkyl halides and ketones are preferred. Two or more organic solvents may be used in combination. The coating liquid can be applied by a known method (eg, extrusion coating method, direct gravure coating method, reverse gravure coating method, die coating method).

(Other materials)
Along with the rod-like liquid crystalline compound, a plasticizer, a surfactant, a polymerizable monomer, etc. can be used in combination to improve the uniformity of the coating film, the strength of the film, the orientation of the rod-like liquid crystalline compound, and the like. These materials are preferably compatible with the rod-like liquid crystalline compound and do not inhibit the alignment.

  Examples of the polymerizable monomer include radically polymerizable or cationically polymerizable compounds. Preferably, it is a polyfunctional radically polymerizable monomer and is preferably copolymerizable with the above-mentioned polymerizable group-containing rod-like liquid crystal compound. Examples thereof include those described in paragraph numbers [0018] to [0020] in JP-A No. 2002-296423. The amount of the compound added is generally in the range of 1 to 50% by mass and preferably in the range of 5 to 30% by mass with respect to the discotic liquid crystalline molecules.

  Examples of the surfactant include conventionally known compounds, and fluorine compounds are particularly preferable. Specific examples include compounds described in paragraph numbers [0028] to [0056] in JP-A-2001-330725.

[Support]
The retardation film of this embodiment may be formed on a support. The support is preferably transparent. Specifically, the support is preferably a transparent support having a light transmittance of 80% or more.
The support preferably has a small wavelength dispersion, and specifically, the ratio of Re (400) / Re (700) is preferably less than 1.2. Among these, a polymer film is preferable as the transparent support. The transparent support can also serve as the first retardation film, the second retardation film, or the polarizing plate protective film. The entire transparent support and the retardation film may constitute the first retardation film or the second retardation film. The support preferably has a small optical anisotropy, and the in-plane retardation (Re) is preferably 20 nm or less, more preferably 10 nm or less, and most preferably 5 nm or less. When the transparent support also serves as the first retardation film, the retardation (Re) is 20 nm to 150 nm, more preferably 40 nm to 115 nm, and further preferably 60 nm to 95 nm. Similarly, Nz is 1.5-7, more preferably 2.0-5.5, and even more preferably 2.5-4.5.

  Examples of the polymer film as the support include cellulose ester, polycarbonate, polysulfone, polyethersulfone, polyacrylate, and polymethacrylate films. Among these, a cellulose ester film is preferable, an acetyl cellulose film is more preferable, and a triacetyl cellulose film is most preferable. The polymer film is preferably formed by a solvent cast method. In general, the thickness of the transparent support is preferably 20 to 500 μm, and more preferably 40 to 200 μm. In addition, in order to improve the adhesion between the transparent support and the layer (adhesive layer, vertical alignment film or retardation layer) provided thereon, surface treatment (eg, glow discharge treatment, corona discharge treatment, ultraviolet ray) is applied to the transparent support. (UV) treatment, flame treatment) may be performed. Further, an adhesive layer (undercoat layer) may be provided on the transparent support. In addition, the transparent support or the long transparent support has an average particle size of 10 to 10 in order to give slippage in the transport process or to prevent sticking between the back surface and the surface after winding. It is preferable to use a polymer layer in which inorganic particles of about 100 nm are mixed at a solid content mass ratio of 5% to 40% and formed on one side of the support by coating or co-casting with the support.

[Polarizing film and protective film for polarizing film]
The retardation film of this aspect is preferably used for the production of an actual liquid crystal display element after a linear polarizing film or a protective film for a polarizing film is bonded. The polarizing film and the protective film for the polarizing film will be described below.
Examples of the polarizing film include an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine polarizing film and the dye polarizing film are generally produced using a polyvinyl alcohol film. The transmission axis of the polarizing film corresponds to a direction perpendicular to the stretching direction of the film. In this embodiment, since the phase film is formed using the rod-like liquid crystalline compound, the transmission axis of the polarizing film is substantially parallel to the major axis direction (slow axis) of the rod-like liquid crystalline molecule. Deploy. Usually, it is preferably bonded to the support side on which the retardation film is formed, but may be bonded to the retardation film side if necessary.

  A transparent protective film may be formed on the surface of the retardation film (surface opposite to the support interface). A transparent polymer film is preferably used as the transparent protective film. That the protective film is transparent means that the light transmittance is 80% or more. As the transparent protective film, generally a cellulose ester film, preferably a triacetyl cellulose film is used. The cellulose ester film is preferably formed by a solvent cast method. The thickness of the transparent protective film is preferably 20 to 500 μm, and more preferably 50 to 200 μm. The protective film preferably has a small retardation based on birefringence. Specifically, the in-plane retardation (Re) is preferably 0 to 30 nm, more preferably 0 to 15 nm, and most preferably 0 to 5 nm. Further, the thickness direction retardation (Rth) is preferably 0 to 40 nm, more preferably 0 to 20 nm, and most preferably 0 to 10 nm. A film having this property can be suitably used as a transparent protective film, but a cellulose acylate or norbornene film is more preferable from the viewpoint of durability of the polarizing film. As a method for reducing the Rth of the cellulose acylate film, a method described in JP-A-11-246704, JP-A-2001-247717, JP-A-2003-379975 (Japanese Patent Application No. 2003-379975). Etc. Rth can also be reduced by reducing the thickness of the cellulose acylate film.

  The retardation film of this embodiment is suitable for use in a liquid crystal display device, particularly an IPS mode liquid crystal display device. By incorporating the retardation film of this embodiment into a liquid crystal display device as a second retardation film described later, two polarizing plates when viewed from an oblique azimuth angle direction without changing any characteristics in the front direction It is possible to improve the contrast reduction caused by the shift of the absorption axis from 90 °, particularly the contrast reduction from an oblique direction of 45 °. Furthermore, the contrast can be further improved by setting the Rth of the protective film in the polarizing film to 40 nm or less. Further, the retardation film of this embodiment can be produced without using a special vertical alignment film, and a second retardation film suitable for the IPS mode can be easily produced.

Hereinafter, an embodiment of a liquid crystal display device having the retardation film of this aspect as a second phase region will be described in detail with reference to the drawings. FIG. 3 is a schematic diagram illustrating an example of a pixel region of a liquid crystal display device having the retardation film of this embodiment. 4 and 5 are schematic views of an embodiment of a liquid crystal display device having the retardation film of this aspect.
Not.

<Liquid crystal display device>
[Configuration of liquid crystal display device]
The liquid crystal display device shown in FIG. 4 has polarizing films 8 and 20, a first retardation film 10, a second retardation film 12, substrates 13 and 17, and a liquid crystal layer 15 sandwiched between the substrates. . The polarizing films 8 and 20 are sandwiched between the protective films 7a and 7b and 19a and 19b, respectively.

  In the liquid crystal display device of FIG. 4, the liquid crystal cell includes substrates 13 and 17 and a liquid crystal layer 15 sandwiched between them. The product Δn · d of the thickness d (μm) of the liquid crystal layer and the refractive index anisotropy Δn is optimal in the range of 0.2 to 0.4 μm for the IPS type having no twisted structure in the transmission mode. In this range, the white display luminance is high and the black display luminance is small, so that a bright and high-contrast display device can be obtained. An alignment film (not shown in FIG. 4) is formed on the surfaces of the substrates 13 and 17 that are in contact with the liquid crystal layer 15, and the liquid crystal molecules are aligned substantially parallel to the surface of the substrate and applied to the alignment film. The orientation direction of the liquid crystal molecules in the no-voltage application state or the low application state is controlled by the rubbing treatment direction (arrows 14 and 18). Further, an electrode (not shown in FIG. 4) capable of applying a voltage to the liquid crystal molecules is formed on the inner surface of the substrate 13 or 17.

  FIG. 3 schematically shows the orientation of liquid crystal molecules in one pixel region (liquid crystal element pixel region 1) of the liquid crystal layer 15. In FIG. 1, the alignment of the liquid crystal molecules in a region of an extremely small area corresponding to one pixel of the liquid crystal layer 15 is set to the rubbing direction 4 of the alignment film formed on the inner surfaces of the substrates 13 and 17, and the substrate 13 and 17 are shown together with electrodes 2 and 3 capable of applying a voltage to liquid crystal molecules formed on the inner surface of 17. In addition, when active driving is performed using a nematic liquid crystal having positive dielectric anisotropy as a field effect type liquid crystal, the liquid crystal molecule alignment direction in a no-voltage applied state or a low applied state is that of the liquid crystal molecules 5a and 5b. Thus, the direction is substantially parallel to the substrate, and black display is obtained at this time. When a voltage is applied between the electrodes 2 and 3, the liquid crystal molecules are aligned in a direction like the liquid crystal molecules 6a and 6b according to the voltage. Usually, bright display is performed in this state.

In FIG. 4 again, the transmission axis 9 of the polarizing film 8 and the transmission axis 21 of the polarizing film 20 are arranged orthogonally. The slow axis 11 of the first retardation film 10 is parallel to the transmission axis 9 of the polarizing film 8 and the slow axis direction 16 of the liquid crystal molecules in the liquid crystal layer 15 during black display.
The liquid crystal display device shown in FIG. 4 shows a configuration in which the polarizing film 8 is sandwiched between two protective films 7a and 7b. However, the protective film 7b is an arbitrary configuration and may not be provided. The polarizing film 20 is also sandwiched between the two protective films 19a and 19b, but the protective film 19a on the side close to the liquid crystal layer 15 may not be provided. In the embodiment of FIG. 4, the first retardation film and the second retardation film may be disposed between the liquid crystal cell and the viewing-side polarizing film with reference to the position of the liquid crystal cell. You may arrange | position between the liquid crystal cell and the polarizing film of the back side. In this embodiment, in any configuration, the second retardation film is disposed so as to be closer to the liquid crystal cell.
The protective films 7a, 7b, 19a and 19b are preferably made of a polymer film having a small optical anisotropy such as a cellulose acylate film. The thickness of the cellulose acylate film used as the transparent protective film is preferably 10 to 100 μm, more preferably 10 to 60 μm, and still more preferably 20 to 45 μm.

  Another embodiment is shown in FIG. The same members as those in FIG. 4 are denoted by the same reference numerals, and detailed description thereof is omitted. In the liquid crystal display device of FIG. 5, the second retardation film 12 is disposed between the polarizing film 8 and the first retardation film 10. Also in the liquid crystal display device of FIG. 5, the protective film 7b or the protective film 19a has an arbitrary configuration and may not be provided. In the embodiment shown in FIG. 5, the first retardation film 10 has a slow axis 11 perpendicular to the transmission axis 9 of the polarizing film 8 and the slow axis direction 16 of the liquid crystal molecules in the liquid crystal layer 15 during black display. It is arranged to become. In the aspect of FIG. 5, the first retardation film and the second retardation film may be disposed between the liquid crystal cell and the polarizing film on the viewing side with reference to the position of the liquid crystal cell. You may arrange | position between the liquid crystal cell and the polarizing film of the back side. In this embodiment, in any configuration, the first retardation film is disposed closer to the liquid crystal cell.

  4 and 5 show a mode of a transmission mode display device including an upper polarizing plate (film) and a lower polarizing plate (film), the present invention is a reflection including only one polarizing plate. It may be a mode mode. In such a case, since the optical path in the liquid crystal cell is doubled, the optimum value Δn · d is about ½ of the above value. In addition, the liquid crystal cell used in the present invention is not limited to the IPS mode, and any liquid crystal display device in which liquid crystal molecules are aligned substantially parallel to the surfaces of the pair of substrates during black display can be used. It can be used suitably. Examples of such a liquid crystal display device include a ferroelectric liquid crystal display device, an antiferroelectric liquid crystal display device, and an ECB type liquid crystal display device.

  In addition, the liquid crystal display device to which the retardation film of this aspect can be applied is not limited to the configuration shown in FIGS. 3 to 5, and may include other members. For example, when a full-color liquid crystal display device is configured, a color filter may be disposed between the liquid crystal layer and the polarizing film. Further, an antireflection treatment or a hard coat may be applied to the surface of the protective film in the polarizing film. Moreover, you may use what gave electroconductivity to the structural member. Further, when used as a transmission type, a cold cathode or a hot cathode fluorescent tube, or a backlight having a light emitting diode, a field emission element or an electroluminescent element as a light source can be disposed on the back side. In this case, the arrangement of the backlight may be on the upper side or the lower side in FIGS.

  In addition, a reflective polarizing plate, a diffusion plate, a prism sheet, or a light guide plate can be disposed between the liquid crystal layer and the backlight. Furthermore, as described above, the liquid crystal display device of the present invention may be of a reflective type. In such a case, only one polarizing plate may be disposed on the observation side, and the back side of the liquid crystal cell or the lower side of the liquid crystal cell. A reflective film is disposed on the inner surface of the substrate. Of course, it is also possible to provide a front light using the light source on the liquid crystal cell observation side.

  Liquid crystal display devices to which the retardation film of this aspect can be applied include an image direct view type, an image projection type, and a light modulation type. Further, an embodiment applied to an active matrix liquid crystal display device using a three-terminal or two-terminal semiconductor element such as TFT or MIM is particularly effective. Of course, an embodiment applied to a passive matrix liquid crystal display device called time-division driving is also effective.

  Hereinafter, preferable optical characteristics, materials, manufacturing methods, and the like of the retardation film used in the first retardation region and the second retardation region will be described in detail.

[First retardation film]
The first retardation film used in the liquid crystal display device has an in-plane retardation (Re) of 20 nm to 150 nm, and from the viewpoint of effectively reducing light leakage in an oblique direction, Re is more preferably 40 nm to 115 nm, and particularly preferably 60 nm to 95 nm. Further, Nz of the first retardation film is 1.5 to 7, and from the viewpoint of effectively reducing light leakage in the oblique direction, Nz of the first retardation film is 2.0 to 5.5. Is more preferable, and 2.5 to 4.5 is particularly preferable.

  Basically, the material and form of the first retardation film are not particularly limited as long as it has the optical characteristics described above. Examples of the first retardation film include a retardation film made of a birefringent polymer film, a film heated after applying a polymer compound on a transparent support, and a low molecular or high-molecular liquid crystalline compound on the transparent support. Any one of a retardation film having a retardation layer formed by coating or transferring can be used. Moreover, each can also be laminated | stacked and used. When the first retardation film is made of a polymer film, it can function as a support for the optically anisotropic layer of the second retardation film described later.

  The birefringent polymer film is preferably one having excellent controllability of birefringence characteristics, transparency and heat resistance. In this case, the polymer material used for the birefringent polymer film is not particularly limited as long as it is a polymer that can achieve uniform biaxial orientation. Preferred are, for example, norbornene polymers, polycarbonate polymers, polyarylate polymers, polyester polymers, aromatic polymers such as polysulfone, cellulose acylate, or two or three of these polymers The polymer etc. which mixed the above are mentioned.

  The biaxial orientation of the film is a film made of the thermoplastic resin produced by an appropriate method such as an extrusion molding method or a casting film forming method, for example, a longitudinal stretching method using a roll, a transverse stretching method using a tenter, or a biaxial stretching method. For example, it can be achieved by performing a stretching treatment. In the above-described longitudinal stretching method using a roll, an appropriate heating method such as a method using a heating roll, a method of heating an atmosphere, or a method of using them together can be employed. In the biaxial stretching method using a tenter, an appropriate method such as a simultaneous biaxial stretching method using an all tenter method or a sequential biaxial stretching method using a roll tenter method can be employed. Moreover, as said birefringent polymer film, a thing with little orientation nonuniformity and phase difference nonuniformity is preferable. The thickness can be appropriately determined depending on the phase difference or the like, but is generally preferably 1 to 300 μm, more preferably 10 to 200 μm, and particularly preferably 20 to 150 μm from the viewpoint of thinning. preferable.

  The norbornene-based polymer is a polymer of monomers mainly composed of norbornene-based monomers such as norbornene and its derivatives, tetracyclododecene and its derivatives, dicyclopentadiene and its derivatives, methanotetrahydrofluorene and its derivatives, Ring-opening polymer of norbornene monomer, ring-opening copolymer of norbornene monomer and other monomer capable of ring-opening copolymerization, addition polymer of norbornene monomer, copolymerizable with norbornene monomer Examples include addition copolymers with other monomers and hydrogenated products thereof. Among these, from the viewpoints of heat resistance, mechanical strength, and the like, a ring-opening polymer hydride of a norbornene monomer is most preferable. The molecular weight of the norbornene-based polymer is appropriately selected according to the purpose of use. However, the polyisoprene or polystyrene equivalent measured by gel permeation chromatography of a cyclohexane solution (or a toluene solution when the polymer resin is not dissolved) is used. The weight average molecular weight is usually about 5,000 to 500,000, preferably 8,000 to 200,000, and more preferably 10,000 to 100,000. When it is in the above-mentioned range, the mechanical strength of the first retardation film and the molding processability are highly balanced and suitable.

  The acyl group of the cellulose acylate is not particularly limited and may be an aliphatic group or an allyl group. Examples of the cellulose acylate include cellulose alkylcarbonyl esters, alkenylcarbonyl esters, aromatic carbonyl esters, aromatic alkylcarbonyl esters, and the like, each of which may further have a substituent. As the substituent, an ester group having a total carbon number of 22 or less is preferable. Preferred cellulose acylates include, for example, acyl groups having an ester part with a total carbon number of 22 or less (for example, acetyl, propionyl, butyroyl, barrel, heptanoyl, octanoyl, decanoyl, dodecanoyl, tridecanoyl, hexadecanoyl, octadecanoyl, etc. ), Arylcarbonyl groups (such as acrylic and methacrylic), allylcarbonyloxy (such as benzoyl and naphthaloyl), and cinnamoyl groups. Among these, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate stearate, cellulose acetate benzoate and the like are preferable. In the case of mixed ester, the ratio is not particularly limited, but acetate is 30 mol of total ester. % Or more is preferable.

Among these, as the polymer material used for the birefringent polymer film, cellulose acylate is preferable, and photographic grade cellulose acylate is particularly preferable. The commercially available photographic grade cellulose acylate has good quality such as viscosity average degree of polymerization and degree of substitution.
Examples of the photographic grade cellulose triacetate include Daicel Chemical Industries, Ltd. (for example, LT-20, 30, 40, 50, 70, 35, 55, 105, etc.) and Eastman Kodak Company (for example, CAB-551). -0.01, CAB-551-0.02, CAB-500-5, CAB-381-0.5, CAB-381-02, CAB-381-20, CAB-321-0.2, CAP-504 -0.2, CAP-482-20, CA-398-3, etc.), those manufactured by Courtles Co., Ltd., Hoechst Co., etc. are preferred, and any of photographic grade cellulose acylates can be used. Further, for the purpose of controlling the mechanical properties and optical properties of the film, as described in JP 2002-277632 A, JP 2002-182215 A, etc., a plasticizer, a surfactant, a letter It is possible to mix a foundation regulator, UV absorber, etc.

  As a method for forming the transparent resin into a sheet or film, for example, either a hot melt molding method or a solution casting method can be used. The heat-melt molding method can be further classified into an extrusion molding method, a press molding method, an inflation molding method, an injection molding method, a blow molding method, a stretch molding method, etc. Among these methods, mechanical strength, surface In order to obtain a film excellent in accuracy and the like, the extrusion molding method, the inflation molding method, and the press molding method are preferable, and the extrusion molding method is most preferable. The molding conditions are appropriately selected depending on the purpose of use and the molding method. In the case of the heat-melt molding method, the cylinder temperature is preferably set in the range of preferably 100 to 200 ° C, more preferably 150 to 350 ° C. The thickness of the sheet or film is preferably 1 to 300 μm, preferably 10 to 200 μm, more preferably 20 to 150 μm.

  When the glass transition temperature of the transparent resin is Tg, the stretching of the sheet or film is preferably in a temperature range of Tg-30 ° C to Tg + 60 ° C, more preferably in a temperature range of Tg-10 ° C to Tg + 50 ° C. In at least one direction, the stretching ratio is preferably 1.01 to 2 times. The stretching direction may be at least one direction, but when the sheet is obtained by extrusion, the direction is preferably the mechanical flow direction (extrusion direction) of the resin. A free shrink uniaxial stretching method, a fixed width uniaxial stretching method, a biaxial stretching method, and the like are preferable. The optical characteristics can be controlled by controlling the draw ratio and the heating temperature.

[Second retardation film]
The retardation film of the present invention is used for the second retardation film of the liquid crystal display device. The in-plane refractive indexes of the second retardation film are substantially equal, and the thickness direction retardation (Rth) is −80 nm to −400 nm. “The in-plane refractive index is substantially equal” means that the in-plane retardation is substantially in the vicinity of 0, and the range is specifically 0 to 20 nm. The more preferable range of Rth of the second retardation film varies depending on the optical characteristics of the other optical members, and in particular, the Rth of the protective film (for example, triacetylcellulose film) of the polarizing film located closer to the optical film. Depending on the situation, it varies greatly. In order to effectively reduce the light leakage in the oblique direction, the Rth of the second retardation film is more preferably −100 nm to −340 nm, and further preferably −120 nm to −270 nm. On the other hand, Re of the second retardation film is substantially a value near zero. Specifically, Re is preferably 0 to 20 nm.

The second retardation film is a film having at least one layer formed by fixing a rod-like liquid crystal compound or composition having a positive refractive index anisotropy substantially perpendicularly to a substrate and then fixing it. Further, the second retardation film can be formed by laminating not only one retardation layer but also a plurality of retardation layers to form the second retardation film exhibiting the above optical characteristics. In addition, the second retardation film may be configured so that the entire laminated body of the support and the retardation layer satisfies the optical characteristics. The second retardation film includes at least the retardation film of the present invention described later.
The term “substantially perpendicular” means that the angle formed between the film surface and the director of the rod-like liquid crystal compound is in the range of 70 ° to 90 °. These liquid crystalline compounds may be aligned obliquely or may be changed so that the inclination angle gradually changes (hybrid alignment). Even in the case of oblique alignment or hybrid alignment, the average inclination angle is preferably 70 ° to 90 °, more preferably 80 ° to 90 °, and most preferably 85 ° to 90 °.

[Liquid Crystal Cell]
The retardation film of the present invention can be used for a liquid crystal display device having liquid crystal cells of various display modes. As described above, the retardation film of the present invention is useful as an optical compensation sheet for liquid crystal cells. As for the optical compensation sheet having an optically anisotropic layer made of liquid crystalline molecules, the transmission type includes TN (Twisted Nematic), IPS (In-Plane Switching), FLC (Ferroelectric Liquid Crystal), OCB (Optically Compensatory STN Bend). (Super Twisted Nematic), VA (Vertically Aligned), ECB (Electrically Controlled Birefringence), and reflection type are TN, HAN (Hybrid Aligned Nematic), G Yes. The retardation film of the present invention can be applied to various liquid crystal display modes depending on the alignment state, but can be suitably used for a transmissive IPS mode.

  The features of the present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, processing details, processing procedures, and the like shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

[Example 1]
(Synthesis example of the above compound (I-1))
3-Aminophenylboronic acid (10 g) was dissolved in tetrahydrofuran (80 ml), and acrylic acid chloride (6.8 ml) was added dropwise with stirring at 0 ° C. After the addition, the mixture was stirred at 0 ° C. for 1 hour, heated to 25 ° C. and stirred for 1 hour. Brine was added and extracted from the aqueous layer with ethyl acetate. After drying overnight with sodium sulfate, the solvent was distilled off under reduced pressure to obtain white brown crystals. The crystals were washed with a mixed solution of 400 ml of ethyl acetate and 100 ml of hexane and filtered to obtain white brown crystals I-1 (12.4 g, yield 89%).
Below, the measurement result of < ¹ > H-NMR is shown.
¹ H-NMR (DMSO-d6) of compound (I-1): δ (ppm) = 5.70 (d, 1H), 6.25 (d, 1H), 6.45 (dd, 1H), 7 .30 (t, 1H), 7.50 (d, 1H), 7.80 (d, 1H), 7.90 (s, 1H), 8.00 (s, 2H), 10.10 (s, 1H).

[Example 2]
(Synthesis example of the polymer (III-1-1))
40 g of dehydrated dimethyl sulfoxide and 0.1 ml of nitrobenzene were added to 10 g of polyvinyl alcohol having a saponification degree of 88 mol% (trade name: PVA-203, manufactured by Kuraray Co., Ltd.) and dissolved by stirring at 50 ° C. 0.78 g of the boric acid compound (I-1) and 0.05 ml of nitrobenzene were added, and stirring was continued at 50 ° C. for 2 hours. 20 ml of methanol was added to the reaction solution, and the resulting mixture was added dropwise to a mixed solution of 320 ml of ethyl acetate and 80 ml of methanol with stirring to precipitate the polymer. The precipitate (polymer) was collected by filtration, soaked in 200 ml of methanol, washed with stirring, and then collected again by filtration and dried to obtain 9.1 g (91% yield) of a bulk polymer (III-1-1). .

When ¹ H-NMR was measured for the obtained polymer (III-1-1), in addition to the main chain proton, hydroxyl proton, and acetyl group proton, the following protons that are not recognized in the raw material PVA-203 are weak in strength. Admitted.
δ (ppm) = 5.7, 6.2, 6.45: Assigned to acryloyl group proton.
δ (ppm) = 7.3, 7.4, 7.8: Assigned to phenyl group proton.
δ (ppm) = 10.1: Assigned to amide group proton.

[Example 3]
1. Formation of Alignment Film Layer An optically isotropic triacetyl cellulose film having a thickness of 100 μm, a width of 150 mm, and a length of 200 mm was used as a transparent support. The alignment film polymer (III-1-1, the structure is shown below) produced above was diluted to 4% by mass in a water / methanol mixed solution to obtain an alignment film coating solution. This coating solution was continuously applied to one side of the transparent support, and the coating layer was heated at 100 ° C. for 2 minutes and dried to form an alignment film having a thickness of 1 μm. Next, a rubbing treatment was continuously performed in the longitudinal direction (conveying direction) of the transparent support to form a liquid crystal alignment film.

Alignment film coating solution composition Alignment film polymer (III-1-1) 1 part by weight Water 18 parts by weight Methanol 6 parts by weight

2. Formation of Liquid Crystalline Compound Layer A coating liquid containing a discotic liquid crystal having the following composition and a polymerizable compound was applied on the alignment film that had been subjected to the rubbing treatment.
Coating liquid composition of liquid crystal compound layer The following discotic liquid crystal compound 100 parts by mass Ethylene oxide modified trimethylolpropane triacrylate (V # 360, manufactured by Osaka Organic Chemical Co., Ltd.) 9.9 parts by mass Photopolymerization initiator (Irgacure 907, Nippon Ciba-Geigy Co., Ltd.) 3.3 parts by mass Sensitizer (Kayacure DETX, Nippon Kayaku Co., Ltd.) 1.1 parts by mass Methyl ethyl ketone 300 parts by mass

3. Evaluation of orientation defect of optically anisotropic layer The optically anisotropic layer produced as described above was observed under a polarizing microscope to evaluate the orientation defect. For the alignment defect, the number of point defects (average value in the range of 1.0 mm ² ) was evaluated.

4). Evaluation of Adhesiveness After the optically anisotropic layer was prepared, the surface was scratched with a metal fitting and then a cellophane tape was attached, and the tape was peeled off in parallel with the optically anisotropic layer to evaluate the adhesiveness. The evaluation criteria were three stages: A: not peeled off at all, B: peeled off slightly, and C: easy to peel off.

5. Measurement of orientation speed (monodomain formation time) The optically anisotropic layer produced as described above is heated to 125 ° C., and the temperature of the optically anisotropic layer is maintained while observing with a polarizing microscope (OPTIPHOTO2, manufactured by Nikon Corporation). The time required for the orientation defect to disappear and the monodomain orientation to be obtained from the start of heating was measured.

6). Production of Polarizing Plate A rolled 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. A transparent support of a saponified roll-shaped cellulose triacetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) on one surface of the polarizing film, and a saponified roll-shaped optically anisotropic layer on the other surface Were laminated together to produce a polarizing plate.

7). Production of Liquid Crystal Display Device A liquid crystal display device was produced by arranging the polarizing plates produced as described above on both sides of a liquid crystal cell and further arranging a backlight.

8). Measurement of leakage light and evaluation of color unevenness of manufactured liquid crystal display device The viewing angle dependence of the transmittance of the manufactured liquid crystal display device was measured by the above method. The suppression angle was measured from the front to the diagonal direction up to 80 ° every 10 °, and the azimuth angle was measured up to 360 ° every 10 ° on the basis of the horizontal right direction (0 °). It was found that the luminance at the time of black display increased as the angle of suppression increased from the front direction, and the leaked light transmittance also increased and took the maximum value near the angle of suppression of 60 °. It was also found that the contrast, which is the ratio between the white display transmittance and the black display transmittance, deteriorates as the black display transmittance increases. Therefore, it was decided to evaluate the viewing angle characteristics with the maximum values of the black display transmittance at the front and the leaked light transmittance at an angle of 60 °.
In this example, the front transmittance was 0.001%, and the maximum value of the leaked light transmittance at a suppression angle of 60 ° was 0.005% at an azimuth angle of 30 °. That is, the contrast ratio at the front was 10000: 1, and the contrast ratio at an angle of 60 ° was 2000: 1.
In addition, the color unevenness of the liquid crystal display device was evaluated visually, and it was very good with no unevenness.

[Example 4]
In the method for producing an optically anisotropic layer shown in Example 3, instead of the alignment film polymer (III-1-1), III-2-1 and III-3- shown in Table 1 below were used. 1, III-5, III-8, III-9, III-14, III-16, III-18 and III-19, respectively, and further changed to A-1 and A-2, respectively, as comparative examples. Except for this, an optically anisotropic layer was prepared in the same manner as in Example 2.

From the results in Table 1, it was found that the liquid crystal display device having the retardation plate of the present invention can display a high-quality image with improved viewing angle and no color unevenness.
Further, the optically anisotropic layer included in the retardation plate as an example of the present invention had few alignment defects even though the alignment time was shortened. From this result, by using the polymer film of the present invention as an alignment film, it is possible to quickly align a liquid crystal compound (particularly a discotic liquid crystal compound) without causing alignment defects such as schlieren defects. I knew it was possible.
Furthermore, the retardation plate as an example of the present invention showed high adhesion between the alignment film and the optically anisotropic layer. This is presumably because the polymer for the polymer film of the present invention and the liquid crystal compound in the optically anisotropic layer are chemically bonded at the interface between these layers. Therefore, the retardation plate of the present invention contributes to the expansion of the viewing angle of the liquid crystal display device and also has excellent durability.

[Example 5]
<Preparation of IPS mode liquid crystal cell 1>
As shown in FIG. 3, electrodes (4 and 5 in FIG. 1) are arranged on a single glass substrate so that the distance between adjacent electrodes is 20 μm, and a polyimide film is used as an alignment film thereon. A rubbing process was performed. The rubbing process was performed in the direction 4 shown in FIG. A polyimide film was provided on one surface of a separately prepared glass substrate, and a rubbing treatment was performed to obtain an alignment film. The two glass substrates are stacked and bonded so that the alignment films face each other, the distance between the substrates (gap; d) is 3.9 μm, and the rubbing directions of the two glass substrates are parallel. A nematic liquid crystal composition having a refractive index anisotropy (Δn) of 0.0769 and a dielectric anisotropy (Δε) of 4.5 was enclosed. The value of d · Δn of the liquid crystal layer was 300 nm.

<Preparation of the first retardation film 1>
A cellulose acetate solution having the following composition was put into a mixing tank and stirred while heating to dissolve each component to prepare a cellulose acetate solution. The solution was filtered at 5 kg / cm ² or less using a filter paper (No. 63, manufactured by Advantech) having a retained particle diameter of 4 μm and a drainage time of 35 seconds.

[Cellulose acetate solution composition]
-100 parts by weight of cellulose acetate having an acetylation degree of 60.9% (polymerization degree 300, Mn / Mw = 1.5)
-Triphenyl phosphate (plasticizer) 7.8 parts by mass-Biphenyl diphenyl phosphate (plasticizer) 3.9 parts by mass-Methylene chloride (first solvent) 300 parts by mass-Methanol (second solvent) 54 parts by mass-1- 11 parts by weight of butanol (third solvent)

  In another mixing tank, 8 parts by mass of the following retardation increasing agent A, 10 parts by mass of the following retardation increasing agent B, 0.28 parts by mass of silicon dioxide fine particles (average particle size: 0.1 μm), 80 parts by mass of methylene chloride and 20 parts by mass of methanol was added and stirred while heating to prepare a retardation increasing agent solution (also serving as a fine particle dispersion). The dope was prepared by mixing 474 parts by mass of the cellulose acetate solution with 40 parts by mass of the retardation increasing agent solution and stirring sufficiently.

  The obtained dope was cast using a band casting machine. A film having a residual solvent amount of 15% by mass was stretched transversely at a stretch ratio of 20% using a tenter under the conditions of 130 ° C., held at 50 ° C. for 30 seconds with the stretched width, and then clipped to remove cellulose. An acetate film was prepared. The residual solvent amount at the end of stretching was 5% by mass, and further dried to prepare a film with the residual solvent amount being less than 0.1% by mass.

  The film thus obtained (first retardation film 1) had a thickness of 80 μm. About the produced 1st phase difference film 1, Re is 70 nm by measuring the light incident angle dependence of Re using an automatic birefringence meter (KOBRA-21ADH, Oji Scientific Instruments Co., Ltd. product). It was found that Rth was 175 nm and Nz was 3.0.

(Synthesis example of the polymer (II-1-1))
40 g of dehydrated dimethyl sulfoxide was added to 10 g of polyvinyl alcohol having a saponification degree of 88 mol% (trade name: PVA-203, manufactured by Kuraray Co., Ltd.) and dissolved by stirring at 50 ° C. 1.02 g of the boronic acid compound (II-17) was added and stirring was continued at 50 ° C. for 2 hours. 20 ml of methanol was added to the reaction solution, and the resulting mixture was added dropwise to a mixed solution of 320 ml of ethyl acetate and 80 ml of methanol with stirring to precipitate the polymer. The precipitate (polymer) was collected by filtration, immersed in 200 ml of methanol, washed with stirring, then collected again by filtration, and dried to obtain 8.5 g (yield 88%) of a bulk polymer (XII-1-1). .

  In the obtained polymer (II-1-1), in addition to main chain protons, hydroxyl protons, and acetyl group protons, phenyl group protons (δ (ppm) = 7.3, not found in the raw material PVA-203, 7.4 and 7.8) were observed with weak intensity.

[Production of Second Retardation Film 1]
The surface of the manufactured first retardation film 1 was subjected to saponification treatment, and the alignment film polymer (II-1-1) coating solution was coated on the film with a wire bar coater so as to be 20 ml / m ² . The film was formed by drying with warm air of 60 ° C. for 60 seconds and further with warm air of 100 ° C. for 120 seconds. Next, the formed film was rubbed in a direction parallel to the slow axis direction of the film to obtain an alignment film.

[Composition of alignment film coating solution]
-Alignment film polymer (II-1-1) 10 parts by mass-Water 371 parts by mass-Methanol 119 parts by mass-Glutaraldehyde 0.5 parts by mass

  Next, the following rod-shaped liquid crystal compound A 3.8 g, photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) 0.06 g, sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 0.02 g, the following air interface A solution was prepared by dissolving 0.002 g of the side vertical alignment agent in 9.2 g of methyl ethyl ketone. This solution was applied to the alignment film side of the film on which the alignment film was formed with a # 4.5 wire bar. This was affixed to a metal frame and heated in a constant temperature bath at 100 ° C. for 2 minutes to align the rod-like liquid crystal compound. Next, UV irradiation is performed at 80 ° C. with a 120 W / cm high-pressure mercury lamp for 20 seconds to crosslink the rod-like liquid crystal compound, and then it is allowed to cool to room temperature to form an optically anisotropic layer on the first retardation film. A retardation film 1 on which a second retardation film was formed was obtained.

Using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments Co., Ltd.), measuring the light incident angle dependency of Re of the manufactured film, and subtracting the pre-measured contribution of the support When the optical properties of only the second retardation film were calculated, it was confirmed that the second retardation film 1 had Re of 0 nm and Rth of −220 nm, and the rod-like liquid crystal was aligned substantially vertically.
The second retardation film 1 thus produced is observed under a polarizing microscope, the alignment state and alignment defects are evaluated, and the number of alignment defects generated in the optically anisotropic layer is observed with an optical microscope. After analysis, (average of 1.0 mm ² range) number of point defects was three in 1.0 mm ² range.
Furthermore, as an evaluation of adhesion, a commercially available tape (PET) was attached to the surface, and the state after peeling off after 30 seconds was observed. As evaluation criteria,
A: Not peeled at all B: 1-10% peeled C: 10-30% peeled D: 30-50% peeled E: 50% or more peeled, as a result of evaluation, the adhesion of the second retardation film 1 was D level.

<Production of Polarizing Plate Protective Film 1>
The following composition was put into a mixing tank, stirred while heating to dissolve each component, and a cellulose acetate solution A was prepared.

[Composition of cellulose acetate solution A]
Cellulose acetate with a substitution degree of 2.86 100 parts by mass Triphenyl phosphate (plasticizer) 7.8 parts by mass Biphenyldiphenyl phosphate (plasticizer) 3.9 parts by mass Methylene chloride (first solvent) 300 parts by mass Methanol (second solvent) 54 parts by mass 1-butanol 11 parts by mass

  The following composition was charged into another mixing tank, stirred while heating to dissolve each component, and an additive solution B-1 was prepared.

[Composition of additive solution B-1]
・ Methylene chloride 80 parts by mass ・ Methanol 20 parts by mass ・ The following optical anisotropy reducing agent 40 parts by mass

40 parts by mass of additive solution B-1 was added to 477 parts by mass of cellulose acetate solution A, and the dope was prepared by sufficiently stirring. The dope was cast from a casting port onto a drum cooled to 0 ° C. The film is peeled off in a state where the solvent content is 70% by mass, both ends in the width direction of the film are fixed with a pin tenter (the pin tenter described in FIG. 3 of JP-A-4-1009), and the solvent content is 3-5% by mass. In this state, the film was dried while maintaining an interval at which the stretching ratio in the transverse direction (direction perpendicular to the machine direction) was 3%. Then, it further dried by conveying between the rolls of the heat processing apparatus, and produced the polarizing plate protective film 1 with a thickness of 80 μm.
Using an automatic birefringence meter (KOBRA-21ADH, manufactured by Oji Scientific Instruments Co., Ltd.), the light incident angle dependence of Re was measured, and the optical characteristics were calculated. Re was 1 nm and Rth was 6 nm. This was confirmed (measurement wavelength λ: 589 nm).

<Preparation of polarizing plate A>
Next, iodine is adsorbed on the stretched polyvinyl alcohol film to produce a polarizing film, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd., Re = 3 nm, Rth = 45 nm) is subjected to saponification treatment. A polarizing plate A was formed on one surface of the polarizing film using a polyvinyl alcohol adhesive.

<Preparation of polarizing plate B>
A polarizing film was produced in the same manner, and a commercially available cellulose acetate film (Fujitac TD80UF, manufactured by Fuji Photo Film Co., Ltd.) was saponified and attached to one side of the polarizing film using a polyvinyl alcohol-based adhesive. . In the same manner, the polarizing plate protective film 1 produced as described above was attached to the other surface of the polarizing film to form a polarizing plate B.

<Production of liquid crystal display device>
Using the polyvinyl alcohol-based adhesive for the polarizing plate A, the retardation film 1 of the present invention was prepared so that the first retardation film 1 side was the polarizing film side and the transmission axis of the polarizing film and the first retardation film A polarizing plate 1 was formed on the side of the polarizing film where the cellulose acetate film was not bonded so that the slow axis of the film 1 was parallel.

This is applied to one of the IPS mode liquid crystal cells 1 produced above so that the slow axis of the first retardation film 1 is parallel to the rubbing direction of the liquid crystal cell (that is, the slow phase of the first retardation film 1). The polarizing plate 1 was attached so that the axis is parallel to the slow axis of the liquid crystal molecules of the liquid crystal cell during black display) and the second retardation film 1 side is on the liquid crystal cell side.
Subsequently, the polarizing plate B is pasted on the other side of the IPS mode liquid crystal cell 1 so that the polarizing plate protective film 1 side is on the liquid crystal cell side and in a crossed Nicol arrangement with the polarizing plate 1. A liquid crystal display device was produced. The leakage light of the liquid crystal display device thus manufactured was measured. The leakage light when observed from the left oblique direction of 60 ° was 0.08%. In addition, the leak light in this specification is measured as follows.
First, the liquid crystal cell 1 is placed on the Schaukasten installed in the dark room without attaching the polarizing plate, and the orientation is 45 degrees to the left with respect to the rubbing direction of the liquid crystal cell and from the normal direction of the liquid crystal cell. A luminance of 1 was measured with a luminance meter installed at a distance of 1 m in the direction of 60 °. Next, the liquid crystal display panel of Example 1 is similarly arranged on the same Schaukasten as described above, and the luminance 2 is similarly measured in the dark display state. It was.

[Example 6]
<Production of second retardation films 2 to 7>
In the production of the second retardation film 1, the alignment film polymer (the above-described specific example (II-1-1)) in the present invention is used as the above-described specific examples (II-4-1) and (II-5), respectively. -1), (II-9), and 2nd phase difference films 2-5 were produced by the same method except having changed into the alignment film polymer represented by (II-12). Further, as a comparative example, a second retardation film 6 was manufactured in the same manner except that PVA-203 was used as the alignment film. Further, a second retardation film 7 was produced which was produced in the same manner as the second retardation film 6 except that the following vertical alignment film (AL-1) was used as the orientation film. The alignment direction of the rod-like liquid crystal of the retardation film thus prepared and the alignment defects were evaluated in the same manner as the second retardation film 1 described above. Further, in Example 5, a polarizing plate was obtained in the same manner as in Example 3, except that the retardation film 1 was replaced with the second retardation films 2 to 5 and the comparative retardation films 6 and 7 in Example 6. 2-7 were produced. Furthermore, a liquid crystal display device was similarly produced using this, and the leakage light observed from the left oblique direction 60 ° was measured. The above results are shown in the following table.

  From the above results, in the embodiment of the present invention, it is possible to produce a retardation film in which rod-like liquid crystals are uniformly and vertically aligned with few defects, and a liquid crystal display device with little light leakage from an oblique direction can be produced. it can. In addition, when an alignment film having a polymerizable group is used, adhesion can be improved.

It is a cross-sectional schematic diagram of one Embodiment of the phase difference plate of this invention. It is a cross-sectional schematic diagram of an example of the polarizing plate using the phase difference plate of this invention. It is the schematic which shows the pixel area example of an example of the liquid crystal display device of this invention. It is the schematic which shows the example of 1 structure of the liquid crystal display device of this invention. It is the schematic which shows the other structural example of the liquid crystal display device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 01 Support body 02 Alignment film 03 Optically anisotropic layer 04 Liquid crystalline compound 05 Phase difference plate 06 Transparent protective film 07 Linear polarizing film 08 Polarizing plate 1 Liquid crystal element pixel area 2 Pixel electrode 3 Display electrode 4 Rubbing direction 5a, 5b Black display Director of liquid crystal compound at the time 6a, 6b Director of liquid crystal compound at white display 7a, 7b, 19a, 19b Protective film for polarizing film 8, 20 Polarizing film 9, 21 Polarization transmission axis 10 of polarizing film First phase difference Film 11 Slow axis 12 of first retardation film Second retardation film 13, 17 Cell substrate 14, 18 Cell substrate rubbing direction 15 Liquid crystal layer 16 Slow axis direction of liquid crystal layer

Claims (8)

A polymer film comprising a compound represented by the following general formula (I) and a polymer:

In general formula (I), R ¹ and R ² each independently represent a hydrogen atom or a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heteroaryl group, and X represents a divalent linking group. Or a substituted or unsubstituted aliphatic hydrocarbon group, aryl group or heterocyclic group, Z represents a substituent having a polymerizable group, and R ¹ and R ² represent an alkylene linking group or an aryl linking group. Or may be linked via a linking group consisting of a combination thereof, and Z may not be present in the molecule. 2. The general formula (I), wherein R ¹ and R ² each represent a hydrogen atom, and Z is a group represented by the following general formula (II), or a group having an oxiranyl moiety or an oxetane moiety. Polymer membrane:

In the general formula (II), R ³ is a hydrogen atom or a methyl group, and L is —O—, —CO—, —NH—, —CO—NH—, —COO—, —O—COO—, alkylene. A divalent linking group selected from a group, an arylene group, a heterocyclic group, and combinations thereof. The polymer film according to claim 1 or 2, wherein the compound represented by the general formula (I) and the polymer are chemically bonded. The polymer film according to claim 1, wherein the polymer is polyvinyl alcohol. A polymer film comprising a polymer represented by the following general formula (III):

In the general formula (III), l is 10 to 99.9 mol%, m is 0 to 70 mol%, n is 0.01 to 80 mol%, and X and Z are general in the condition of l + m + n = 100 It is synonymous with X and Z in Formula (I). A liquid crystal alignment film comprising the polymer film according to claim 1. A retardation plate comprising a transparent support, the liquid crystal alignment film according to claim 6, and an optically anisotropic layer containing at least one liquid crystalline compound. A liquid crystal display device comprising the retardation plate according to claim 7.

Images