JP2009193046A - Optical compensation film, polarizing plate and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical compensation film having no fine concavo-convex pattern on the surface. <P>SOLUTION: The optical compensation film includes an optical anisotropy layer having a liquid crystal composition fixed in an aligned state, wherein the optical anisotropy layer has a surface energy of not more than 27 mN/m and average surface roughness (Ra) of not more than 1.0 nm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an optical compensation film, a polarizing plate using the optical compensation film, and a liquid crystal display device having the polarizing plate.

As an optical compensation film for a liquid crystal display (LCD), an optical compensation film having an optically anisotropic layer containing a liquid crystalline compound has been proposed (for example, see Patent Documents 1 to 4).
The optically anisotropic layer containing a liquid crystal compound is generally formed by applying a liquid crystal composition on a support made of a polymer film or the like. In order to apply uniformly, it is known to add a fluoroaliphatic group-containing polymer that reduces the surface energy (see, for example, Patent Document 5). However, in the conventional fluoroaliphatic group-containing polymer having a great effect of improving the film thickness uniformity, a depression having a diameter of submicron to micron order and a depth of nanometer order is generated on the surface of the optically anisotropic layer. The dent causes depolarization and scattering of the transmitted light, which is a cause of a decrease in contrast of the liquid crystal display device. On the other hand, there are fluoroaliphatic group-containing polymers that do not generate dents in the above order, but the effect of improving the film thickness uniformity is insufficient, and film thickness unevenness occurs when the solvent of the coating solution is dried.
JP-A-6-214116 US Pat. No. 5,583,679 US Pat. No. 5,646,703 German Patent Application Publication No. 3911620 JP 2004-198511 A

An object of the present invention is to solve the above-mentioned problems in the prior art, and to provide an optical compensation film having no or little fine unevenness on the surface and no film thickness unevenness, and a polarizing plate using the same.
Another object of the present invention is to provide a liquid crystal display device that has high contrast, excellent viewing angle characteristics, and can display a high-quality image without unevenness.

一般式（Ａ）中、Ｍｐはポリマー主鎖の一部を構成する３価の基を表し、Ｌは単結合又は２価の連結基を表し、Ｘは置換もしくは無置換の芳香族縮合環官能基を表す。
［３］ 前記一般式（Ａ）中のＸが、炭素原子数５〜３０の無置換もしくは置換の芳香族縮合環官能基である［２］の光学補償フィルム。
［４］前記一般式（Ａ）中のＸが、炭素原子数１０〜２０の無置換もしくは置換のナフチル基である［２］又は［３］の光学補償フィルム。
［５］ 前記一般式（Ａ）において、前記Ｍｐが下記Ｍｐ−１又はＭｐ−２を表し、前記Ｌが、−Ｏ−、−ＮＲ^a11−（Ｒ^a11は、水素原子、炭素原子数１〜１０の脂肪族炭化水素基を表す。）、−Ｓ−、−Ｃ（＝Ｏ）−、−Ｓ（＝Ｏ）₂−、及び、炭素原子数１〜２０の置換もしくは無置換のアルキレン基、ならびに、これらの２個以上を連結して形成される基から選択される２価の連結基を表す［２］〜［４］のいずれかの光学補償フィルム：

＊は、Ｌとの連結位置を示す。
［６］ 前記フルオロ脂肪族基含有モノマーより誘導される構成単位が、下記一般式（Ｂ）で表される構成単位である［２］〜［５］のいずれかの光学補償フィルム：

一般式（Ｂ）中、Ｍｐ'はポリマー主鎖の一部を構成する３価の基を表し、Ｌ'は単結合又は２価の連結基を表し、Ｒｆは少なくとも一つのフッ素原子を含有する置換基を表す。［７］ 前記光学異方性層の、波長４５０ｎｍの面内レターデーション値Ｒｅ（４５０ｎｍ）及び波長６５０ｎｍの面内レターデーション値Ｒｅ（６５０ｎｍ）が、下記式を満たす［１］〜［６］のいずれかの光学補償フィルム。
Ｒｅ（４５０ｎｍ）／Ｒｅ（６５０ｎｍ）＜１．２５
［８］ 偏光子と［１］〜［７］のいずれかの光学補償フィルムを含む偏光板。
［９］ ［１］〜［７］のいずれかの光学補償フィルム、又は［８］の偏光板を含む液晶表示装置。 Means for solving the above-mentioned problems are as follows.
[1] An optical compensation film including an optically anisotropic layer formed by fixing a liquid crystal composition in an alignment state, wherein the surface energy of the optically anisotropic layer is 27 mN / m or less, and the surface average roughness ( An optical compensation film in which Ra) is 1.0 nm or less.
[2] The liquid crystal composition includes at least one liquid crystalline compound and at least one polymer including a structural unit represented by the following general formula (A) and a structural unit derived from a fluoroaliphatic group-containing monomer. Containing [1] optical compensation film:

In general formula (A), Mp represents a trivalent group constituting a part of the polymer main chain, L represents a single bond or a divalent linking group, and X represents a substituted or unsubstituted aromatic condensed ring function. Represents a group.
[3] The optical compensation film according to [2], wherein X in the general formula (A) is an unsubstituted or substituted aromatic condensed ring functional group having 5 to 30 carbon atoms.
[4] The optical compensation film according to [2] or [3], wherein X in the general formula (A) is an unsubstituted or substituted naphthyl group having 10 to 20 carbon atoms.
[5] In the general formula (A), the Mp represents the following Mp-1 or Mp-2, and the L represents —O—, —NR ^a11 — (R ^a11 represents a hydrogen atom, a carbon atom number of 1 to 10 represents an aliphatic hydrocarbon group), -S-, -C (= O)-, -S (= O) _2- , and a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, In addition, the optical compensation film according to any one of [2] to [4], which represents a divalent linking group selected from a group formed by linking two or more of these:

* Indicates a connection position with L.
[6] The optical compensation film according to any one of [2] to [5], wherein the structural unit derived from the fluoroaliphatic group-containing monomer is a structural unit represented by the following general formula (B):

In general formula (B), Mp ′ represents a trivalent group constituting a part of the polymer main chain, L ′ represents a single bond or a divalent linking group, and Rf contains at least one fluorine atom. Represents a substituent. [7] The in-plane retardation value Re (450 nm) at a wavelength of 450 nm and the in-plane retardation value Re (650 nm) at a wavelength of 650 nm of the optically anisotropic layer satisfy the following formulas [1] to [6] Any optical compensation film.
Re (450 nm) / Re (650 nm) <1.25
[8] A polarizing plate comprising a polarizer and the optical compensation film of any one of [1] to [7].
[9] A liquid crystal display device comprising the optical compensation film of any one of [1] to [7] or the polarizing plate of [8].

Hereinafter, the optical compensation film, the polarizing plate, and the liquid crystal display device according to the present invention will be described in detail.
In the description of the present embodiment, “45 °”, “parallel”, and “orthogonal” include errors of less than ± 5 ° with respect to objects such as a reference surface, axis, and direction. This error is preferably less than 4 °, more preferably less than 3 °.
Regarding the angle, “+” means the clockwise direction, and “−” means the counterclockwise direction.
The “slow axis” means the direction in which the refractive index is maximum, and the “visible light region” means the wavelength of light of 380 to 780 nm.
Further, the refractive index measurement wavelength is a value in the visible light region (λ = 550 nm) unless otherwise specified.

In the description of this embodiment, the term “polarizing plate” is used to include both a long polarizing plate and a polarizing plate cut into a size incorporated in a liquid crystal display device unless otherwise specified. ing. Here, “cutting” includes “punching” and “cutting out”.
In the description of the present embodiment, “polarizing film” and “polarizing plate” are distinguished from each other. However, “polarizing plate” is a laminate having a transparent protective film that protects the polarizing film on at least one side of “polarizing film”. It shall mean the body.

In the description of the present embodiment, the “molecular symmetry axis” refers to a symmetry axis when the molecule has a rotational symmetry axis, but strictly requires that the molecule is rotationally symmetric. is not.
In general, in a discotic liquid crystalline compound, the molecular symmetry axis coincides with an axis perpendicular to the disc surface passing through the center of the disc surface, and in a rod-like liquid crystalline compound, the molecular symmetry axis is the long axis of the molecule. Match.

In this specification, Re (λ) and Rth (λ) represent in-plane retardation (nm) and retardation in the thickness direction (nm), respectively, at a wavelength λ. Re (λ) is measured by making light having a wavelength of λ nm incident in the normal direction of the film in KOBRA 21ADH or WR (manufactured by Oji Scientific Instruments).
When the film to be measured is represented by a uniaxial or biaxial refractive index ellipsoid, Rth (λ) is calculated by the following method.
Rth (λ) is the Re (λ), and the in-plane slow axis (determined by KOBRA 21ADH or WR) is the tilt axis (rotation axis). The light of wavelength λ nm is incident from each of the inclined directions in steps of 10 ° from the normal direction to 50 ° on one side with respect to the normal direction of the film (with the direction of the rotation axis as the rotation axis), and a total of 6 points are measured. KOBRA 21ADH or WR calculates based on the measured retardation value, the assumed value of the average refractive index, and the input film thickness value.
In the above case, in the case of a film having a direction in which the retardation value is zero at a certain tilt angle with the in-plane slow axis from the normal direction as the rotation axis, retardation at a tilt angle larger than the tilt angle. The value is calculated by KOBRA 21ADH or WR after changing its sign to negative.
The retardation value is measured from two inclined directions with the slow axis as the tilt axis (rotation axis) (if there is no slow axis, the arbitrary direction in the film plane is the rotation axis). Based on the value, the assumed value of the average refractive index, and the input film thickness value, Rth can also be calculated from the following equations (A) and (B).

ただし、上記のＲｅ（θ）は法線方向から角度θ傾斜した方向におけるレターデーション値をあらわす。
また、式（Ａ）におけるｎｘは、面内における遅相軸方向の屈折率を表し、ｎｙは面内においてｎｘに直交する方向の屈折率を表し、ｎｚはｎｘ及びｎｙに直交する方向の屈折率を表す。ｄは膜厚である。

However, Re (θ) represents the retardation value in the direction inclined by the angle θ from the normal direction.
Further, nx in the formula (A) represents the refractive index in the slow axis direction in the plane, ny represents the refractive index in the direction orthogonal to nx in the plane, and nz represents the refraction in the direction orthogonal to nx and ny. Represents a rate. d is the film thickness.

When the film to be measured is a film that cannot be expressed by a uniaxial or biaxial refractive index ellipsoid, that is, a film without a so-called optical axis, Rth (λ) is calculated by the following method.
Rth (λ) is the above-mentioned Re (λ), and the in-plane slow axis (determined by KOBRA 21ADH or WR) is the tilt axis (rotary axis). 11 points of light having a wavelength of λ nm are incident from each tilted direction in 10 ° steps, and based on the measured retardation value, assumed average refractive index, and input film thickness value. KOBRA 21ADH or WR is calculated.
In the above measurement, as the assumed value of the average refractive index, the values in the polymer handbook (John Wiley & Sons, Inc.) and catalogs of various optical films can be used.
Moreover, about the thing whose average refractive index value is not known, it can measure with an Abbe refractometer. The average refractive index values of main optical films are exemplified below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), Polystyrene (1.59).
The KOBRA 21ADH or WR calculates nx, ny, and nz by inputting the assumed average refractive index and the film thickness. Nz = (nx−nz) / (nx−ny) is further calculated from the calculated nx, ny, and nz.

[Optical compensation film]
The optical compensation film of the present invention includes at least an optically anisotropic layer formed by fixing the liquid crystal composition in an aligned state. The optically anisotropic layer has a surface energy of 27 mN / m or less and a surface average roughness (Ra) of 1.0 nm or less. The surface energy of the optically anisotropic layer is preferably 26 mN / m or less, and more preferably 25 mN / m or less. In order to reduce film thickness unevenness, the lower the surface energy, the better. On the other hand, if the surface energy is too low, repelling occurs when the optically anisotropic layer is formed, or adhesion to the optically anisotropic layer occurs. Problems such as difficulty in attaching the agent occur. Therefore, in general, the surface energy of the optically anisotropic layer is preferably about 15 mN / m or more. The surface energy of the optically anisotropic layer is determined by the contact angle method (dropping a droplet having a known surface tension on the solid surface, measuring the contact angle with the solid surface, and using the Owens and Wendt equation, etc.) (Calculation).
In addition, the surface average roughness (Ra) of the optically anisotropic layer is preferably 0.9 nm or less, and more preferably 0.7 nm or less. The smaller the average surface roughness, the better. On the other hand, if the surface is too smooth, problems such as poor slipping and adhesion to the back surface occur when a long optical compensation film is rolled up. . Therefore, in general, the surface average roughness is preferably about 0.2 nm or more. The surface average roughness in the above range can be measured by AFM or the like.

The optical compensation film of the present invention highly compensates the liquid crystal display device by having a laminated structure of two or more layers including an optically anisotropic layer obtained by fixing the alignment of a liquid crystal compound and another optically anisotropic layer. This is preferable.
In an embodiment composed of two or more optically anisotropic layers, in this specification, an optically anisotropic layer obtained by fixing the alignment of a liquid crystal compound is referred to as a first optically anisotropic layer. The first optical anisotropic layer can be provided on the support via an alignment film. At this time, the support can also function as a second optically anisotropic layer.

<First optically anisotropic layer (liquid crystalline compound layer)>
The first optically anisotropic layer (liquid crystalline compound layer) used in the present invention contains a liquid crystalline compound. The first optically anisotropic layer (liquid crystalline compound layer) may be directly formed on the surface of the support, or may be formed on an alignment film formed on the support.
The liquid crystalline compound used for the first optically anisotropic layer (liquid crystalline compound layer) is preferably a discotic liquid crystalline compound.
Further, the in-plane retardation Re measured from the film normal direction of the first optically anisotropic layer is preferably 10 to 100 nm, and more preferably 20 to 80 nm.
The first optically anisotropic layer is preferably designed so as to compensate for the liquid crystalline compound in the liquid crystal cell in the black display of the liquid crystal display device. Regarding the alignment state of the liquid crystal compound in the liquid crystal cell, IDW'00, FMC7-2, p. 411-414.
In this specification, in the production of the first optically anisotropic layer, it is referred to as “liquid crystalline compound layer” until the orientation of the contained liquid crystalline compound is fixed, and the orientation of the liquid crystalline compound is fixed. After this, it will be expressed as “optically anisotropic layer”.

<< Discotic Liquid Crystalline Compound >>
The discotic liquid crystalline compound in the present invention may be a polymer liquid crystal or a low molecular liquid crystal, and further includes those in which the low molecular liquid crystal is cross-linked and no longer exhibits liquid crystallinity.
Examples of discotic liquid crystalline compounds include benzene derivatives (reported in C. Destrade et al., Mol. Cryst. 71, 111 (1981)), truxene derivatives (C. Destrade et al., Mol. Cryst et al., Mol. Cryst et al. 122, 141 (1985), Physics lett, A, 78, 82 (1990)), cyclohexane derivatives (Research report of B. Kohne et al., Angew. Chem. 96, 70 (1984). And azacrown- or phenylacetylene-based macrocycles (JM Lehn et al., J. Chem. Commun., P. 1794 (1985), J. Zhang et al., J. Am. Chem. Soc., 116, 2655 (1994)) included.

The discotic liquid crystalline compound has a liquid crystallinity having a structure in which a linear alkyl group, an alkoxy group, or a substituted benzoyloxy group is radially substituted as a side chain of the mother nucleus with respect to the mother nucleus at the center of the molecule. The compounds shown are also included. The molecule or the assembly of molecules is preferably a compound having rotational symmetry and imparting a certain orientation.
When an optically anisotropic layer is formed from a discotic liquid crystalline compound, the compound finally contained in the optically anisotropic layer no longer needs to exhibit liquid crystallinity.
For example, a low-molecular discotic liquid crystalline compound has a group that reacts with heat or light, and the group reacts with heat or light to polymerize or crosslink to increase the molecular weight. When a layer is formed, the compound contained in the optically anisotropic layer may no longer have liquid crystallinity.
Preferred examples of the discotic liquid crystalline compound are described in JP-A-8-50206, and the polymerization of the discotic liquid crystalline compound is described in JP-A-8-27284.

In order to fix the discotic liquid crystalline compound by polymerization, it is necessary to bond a polymerizable group as a substituent to the discotic core of the discotic liquid crystalline compound.
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.
Therefore, the discotic liquid crystalline compound having a polymerizable group is preferably a compound represented by the following general formula (DI).
Examples of the liquid crystalline compound used in the present invention include those represented by the general formula (DI).

[Compound represented by formula (DI)]
The compound represented by the general formula (DI) used in the present invention preferably exhibits discotic liquid crystallinity, and particularly preferably exhibits a discotic nematic phase.

In the general formula (DI), Y ¹¹ , Y ¹² and Y ¹³ each independently represent a methine or a nitrogen atom. L ¹ , L ² and L ³ each independently represents a single bond or a divalent linking group. H ^1, the H ^2, H ³ are each independently, represent the general formula (DI-A) or the following formula (DI-B). R ¹ , R ² and R ³ each independently represents the following general formula (DI-R).

In the general formula (DI), Y ¹¹ , Y ¹² and Y ¹³ each independently represent a methine or nitrogen atom. When Y ¹¹ , Y ¹² and Y ¹³ are each methine, the hydrogen atom of methine may be substituted with a substituent. Examples of the substituent that methine may have include, for example, alkyl group, alkoxy group, aryloxy group, acyl group, alkoxycarbonyl group, acyloxy group, acylamino group, alkoxycarbonylamino group, alkylthio group, arylthio group, halogen Mention may be made of atoms and cyano groups. Among these, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an acyloxy group, a halogen atom, and a cyano group are more preferable. The same applies to the substituents which may be substituted) 1-12 alkyl groups, C1-12 alkoxy groups, C2-12 alkoxycarbonyl groups, C2-12 acyloxy groups, halogen atoms and cyano Groups are more preferred.

Y ¹¹ , Y ¹² and Y ¹³ are preferably all methine, and methine is preferably unsubstituted.

In the general formula (DI), L ¹ , L ² and L ³ are each independently a single bond or a divalent linking group. The divalent linking group includes —O—, —S—, —C (═O) —, —NR ⁷ —, —CH═CH—, —C≡C—, a divalent cyclic group, and combinations thereof. A divalent linking group selected from the group consisting of R ⁷ is an alkyl group having 1 to 7 carbon atoms or a hydrogen atom, more preferably an alkyl group having 1 to 4 carbon atoms or a hydrogen atom, and a methyl group, ethyl group or hydrogen atom. Is more preferable, and a hydrogen atom is particularly preferable.

The divalent cyclic group represented by L ¹ , L ² and L ³ is preferably a 5-membered ring, 6-membered ring or 7-membered ring, more preferably a 5-membered ring or 6-membered ring, More preferably, it is 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. Further, 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. The cyclic group preferably contains an aromatic ring and a heterocyclic ring.

  Of the divalent cyclic group, the cyclic group having a benzene ring is preferably a 1,4-phenylene group. As the cyclic group having a naphthalene ring, a naphthalene-1,5-diyl group and a naphthalene-2,6-diyl group are preferable. The cyclic group having a cyclohexane ring is preferably a 1,4-cyclohexylene group. The cyclic group having a pyridine ring is preferably a pyridine-2,5-diyl group. The cyclic group having a pyrimidine ring is preferably a pyrimidine-2,5-diyl group.

The divalent cyclic group represented by L ¹ , L ² or L ³ may have a substituent. Examples of the substituent include a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 16 carbon atoms, an alkenyl group having 2 to 16 carbon atoms, an alkynyl group having 2 to 16 carbon atoms, and 1 carbon atom. An alkyl group substituted with -16 halogen atoms, an alkoxy group having 1 to 16 carbon atoms, an acyl group having 2 to 16 carbon atoms, an alkylthio group having 1 to 16 carbon atoms, and 2 carbon atoms -16 acyloxy groups, alkoxycarbonyl groups having 2 to 16 carbon atoms, carbamoyl groups, carbamoyl groups substituted with alkyl groups having 2 to 16 carbon atoms, and acylamino groups having 2 to 16 carbon atoms It is.

L ¹ , L ² and L ³ include a single bond, * —O—CO—, * —CO—O—, * —CH═CH—, * —C≡C—, * -2 valent cyclic group— * -O-CO-2 valent cyclic group-, * -CO-O-2 valent cyclic group-, * -CH = CH-2 valent cyclic group-, * -C≡C-2 valent cyclic. Group-, * -2 valent cyclic group-O-CO-, * -2 valent cyclic group-CO-O-, * -2 valent cyclic group-CH = CH-, or * -2 valent cyclic group- C≡C— is preferred. In particular, a single bond, * -CH = CH-, * -C≡C-, * -CH = CH-2 valent cyclic group- or * -C≡C-2 valent cyclic group- is more preferable, Is more preferable. Here, * represents a position bonded to a 6-membered ring including Y ¹¹ , Y ¹² and Y ¹³ in the general formula (I).

In the general formula (DI), H ¹ , H ² and H ³ each independently represent the following general formula (DI-A) or the following general formula (DI-B).

In the general formula (DI-A), YA ¹ and YA ² each independently represents a methine or a nitrogen atom. At least one of YA ¹ and YA ² is preferably a nitrogen atom, and more preferably both are nitrogen atoms. XA represents an oxygen atom, a sulfur atom, methylene or imino. XA is preferably an oxygen atom. * Represents a position where L ^{1 to} L ³ are bonded, and ** represents a position where R ^{1 to} R ³ are bonded.

In the general formula (DI-B), YB ¹ and YB ² each independently represent a methine or a nitrogen atom. At least one of YB ¹ and YB ² is preferably a nitrogen atom, and more preferably both are nitrogen atoms. XB represents an oxygen atom, a sulfur atom, methylene or imino. XB is preferably an oxygen atom. * Represents a position where L ^{1 to} L ³ are bonded, and ** represents a position where R ^{1 to} R ³ are bonded.

R ¹ , R ² and R ³ each independently represents the following general formula (DI-R).
General formula (DI-R)
*-(-L ²¹ -F ¹ ) _n1 -L ²² -L ²³ -Q ¹

In the general formula (DI-R), * represents a position bonded to H ¹ , H ² or H ³ in the general formula (DI). F ¹ represents a divalent linking group having at least one cyclic structure. L ²¹ represents a single bond or a divalent linking group. When L ²¹ is a divalent linking group, it consists of —O—, —S—, —C (═O) —, —NR ⁷ —, —CH═CH—, —C≡C—, and combinations thereof. A divalent linking group selected from the group is preferable. R ⁷ is an alkyl group having 1 to 7 carbon atoms or a hydrogen atom, more preferably an alkyl group having 1 to 4 carbon atoms or a hydrogen atom, and a methyl group, ethyl group or hydrogen atom. Is more preferable, and a hydrogen atom is particularly preferable.

L ²¹ represents a single bond, ** — O—CO—, ** — CO—O—, ** — CH═CH— or ** — C≡C— (where ** represents a general formula (DI-R Represents the left side of L ^{21 in} the formula (A). A single bond is particularly preferable.

F ¹ in the general formula (DI-R) represents a divalent cyclic linking group having at least one cyclic structure. The cyclic structure 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 even more preferably a 6-membered ring. The cyclic structure may be a condensed ring. However, it is more preferably a monocycle than a condensed ring. Further, 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, a naphthalene ring, an anthracene ring, and a phenanthrene ring. Examples of the aliphatic ring include a cyclohexane ring. Examples of the heterocyclic ring include a pyridine ring and a pyrimidine ring.

Of F ¹ , those having a benzene ring are preferably a 1,4-phenylene group or a 1,3-phenylene group. Those having a naphthalene ring include naphthalene-1,4-diyl group, naphthalene-1,5-diyl group, naphthalene-1,6-diyl group, naphthalene-2,5-diyl group, naphthalene-2,6- A diylnaphthalene-2,7-diyl group is preferred. Those having a cyclohexane ring are preferably 1,4-cyclohexylene groups. Pyridine-2,5-diyl groups are preferred as those having a pyridine ring. As a compound having a pyrimidine ring, a pyrimidine-2,5-diyl group is preferable. F ¹ is particularly preferably a 1,4-phenylene group, a 1,3-phenylenenaphthalene-2,6-diyl group and a 1,4-cyclohexylene group.

F ¹ may have a substituent. Examples of the substituent include a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, nitro group, alkyl group having 1 to 16 carbon atoms, alkenyl group having 1 to 16 carbon atoms, carbon An alkynyl group having 2 to 16 atoms, an alkyl group substituted with a halogen atom having 1 to 16 carbon atoms, an alkoxy group having 1 to 16 carbon atoms, an acyl group having 2 to 16 carbon atoms, and 1 to 1 carbon atoms 16 alkylthio groups, acyloxy groups having 2 to 16 carbon atoms, alkoxycarbonyl groups having 2 to 16 carbon atoms, carbamoyl groups, carbamoyl groups substituted with alkyl groups having 2 to 16 carbon atoms, and 2 to 2 carbon atoms 16 acylamino groups are included. The substituent is preferably a halogen atom, a cyano group, an alkyl group having 1 to 6 carbon atoms, or an alkyl group substituted with a halogen atom having 1 to 6 carbon atoms, and a halogen atom or an alkyl having 1 to 4 carbon atoms. Group, an alkyl group substituted with a halogen atom having 1 to 4 carbon atoms is more preferable, and a halogen atom, an alkyl group having 1 to 3 carbon atoms, and a trifluoromethyl group are particularly preferable.

n1 represents an integer of 0 to 4. As n1, the integer of 1-3 is preferable and 1 or 2 is preferable. When n1 is 0, L ²² in the formula (DI-R) is directly bonded to H ^{1 to} H ³ in the general formula (D1). When n1 is 2 or more, each -L ²¹ -F ¹ may be the same or different.

L ²² represents —O—, —O—CO—, —CO—O—, —O—CO—O—, —S—, —NH—, —SO ₂ —, —CH ₂ —, —CH═CH. -Or -C≡C- is represented. Preferably, -O -, - O-CO -, - CO-O -, - O-CO-O -, - CH 2 -, - CH = CH- or a -C≡C-, more preferably, —O—, —O—CO—, —CO—O—, —O—CO—O— or —CH ₂ —.
Here, when it is a group containing a hydrogen atom among the above, the hydrogen atom may be replaced by a substituent. Examples of other substituents include a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 6 carbon atoms, an alkyl group substituted with a halogen atom having 1 to 6 carbon atoms, and 1 to 6 carbon atoms. Alkoxy groups having 2 to 6 carbon atoms, alkylthio groups having 1 to 6 carbon atoms, acyloxy groups having 2 to 6 carbon atoms, alkoxycarbonyl groups having 2 to 6 carbon atoms, carbamoyl groups, carbon atoms The carbamoyl group substituted by the C2-C6 alkyl group and the C2-C6 acylamino group are contained. In particular, a halogen atom and an alkyl group having 1 to 6 carbon atoms are preferable.

L ²³ represents —O—, —S—, —C (═O) —, —SO ₂ —, —NH—, —CH ₂ —, —CH═CH—, —C≡C—, and two of these. A divalent linking group selected from the groups formed by linking the above. Here, the hydrogen atoms of —NH—, —CH ₂ —, and —CH═CH— may be replaced with other substituents. Examples of other substituents include a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 6 carbon atoms, an alkyl group substituted with a halogen atom having 1 to 6 carbon atoms, and 1 to 6 carbon atoms. Alkoxy group having 2 to 6 carbon atoms, alkylthio group having 1 to 6 carbon atoms, acyloxy group having 2 to 6 carbon atoms, alkoxycarbonyl group having 2 to 6 carbon atoms, carbamoyl group, carbon atom A carbamoyl group substituted with an alkyl group having 2 to 6 carbon atoms and an acylamino group having 2 to 6 carbon atoms are included. In particular, a halogen atom and an alkyl group having 1 to 6 carbon atoms are preferable. By being substituted with these substituents, the solubility of the compound represented by the general formula (DI) in the solvent can be improved, and the liquid crystal composition can be easily prepared as a coating solution.

L ²³ is preferably a linking group selected from the group consisting of —O—, —C (═O) —, —CH ₂ —, —CH═CH—, —C≡C—, and combinations thereof. L ²³ preferably contains 1 to 20 carbon atoms, more preferably 2 to 14 carbon atoms. Furthermore, L ²³ is -CH ₂ - preferably contains 1 to 16 a, -CH ₂ - and more preferably a containing 2-12.

Q ¹ is a polymerizable group or a hydrogen atom. When the compound represented by the general formula (DI) is used for producing an optical film or the like that requires that the phase difference does not change due to heat, such as an optical compensation film, Q ¹ represents a polymerizable group. It is preferable that The polymerization reaction 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.

  Furthermore, the polymerizable group is particularly preferably a functional group capable of addition polymerization reaction. Such a polymerizable group is preferably a polymerizable ethylenically unsaturated group or a ring-opening polymerizable group.

  Examples of the polymerizable ethylenically unsaturated group include the following formulas (M-1) to (M-6).

  In formula (M-3) and formula (M-4), R represents a hydrogen atom or an alkyl group. R is preferably a hydrogen atom or a methyl group. Among the above (M-1) to (M-6), (M-1) or (M-2) is preferable, and (M-1) is more preferable.

  The ring-opening polymerizable group is preferably a cyclic ether group, and more preferably an epoxy group or an oxetanyl group, and most preferably an epoxy group.

  In the present invention, it is also preferable to use a compound represented by the following general formula (DII) or a compound represented by the following general formula (DIII) as the discotic liquid crystalline compound.

（一般式（ＤＩＩ）中、Ｙ³¹、Ｙ³²、Ｙ³³はそれぞれ独立にメチン又は窒素原子を表す。Ｒ³¹、Ｒ³²、Ｒ³³はそれぞれ独立に下記一般式（ＤＩＩ−Ｒ）で表される。）

(In the general formula (DII), Y ³¹ , Y ³² and Y ³³ each independently represent a methine or nitrogen atom. R ³¹ , R ³² and R ³³ are each independently represented by the following general formula (DII-R). )

In the general formula (DII), Y ³¹ , Y ³² and Y ³³ each independently represent a methine or a nitrogen atom. Y ³¹ , Y ³² and Y ³³ are the same as the definitions of Y ¹¹ , Y ¹² and Y ^{13 in} the general formula (DI), respectively, and preferred ranges are also synonymous.

R ³¹ , R ³² and R ³³ are each independently represented by the general formula (DII-R).

In the general formula (DII-R), A ³¹ and A ³² each independently represents a methine or a nitrogen atom. As A ³¹ and A ³² , at least one is preferably a nitrogen atom, and more preferably both are nitrogen atoms.
X ³ represents an oxygen atom, a sulfur atom, methylene, or imino. X ³ is preferably an oxygen atom.

In General Formula (DII-R), F ² represents a divalent cyclic linking group having a 6-membered cyclic structure. The 6-membered ring contained in F ² may be a condensed ring. However, it is more preferably a monocycle than a condensed ring. The 6-membered ring contained in F ² may be any of an aromatic ring, an aliphatic ring, and a heterocyclic ring.
Examples of the aromatic ring include a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthrene ring. Examples of the aliphatic ring include a cyclohexane ring. Examples of the heterocyclic ring include a pyridine ring and a pyrimidine ring.

  Among the divalent cyclic groups, the cyclic group having a benzene ring is preferably a 1,4-phenylene group or a 1,3-phenylene group. As a cyclic group having a naphthalene ring, naphthalene-1,4-diyl group, naphthalene-1,5-diyl group, naphthalene-1,6-diyl group, naphthalene-2,5-diyl group, naphthalene-2,6 -Diyl groups and naphthalene-2,7-diyl groups are preferred. The cyclic group having a cyclohexane ring is preferably a 1,4-cyclohexylene group. The cyclic group having a pyridine ring is preferably a pyridine-2,5-diyl group. The cyclic group having a pyrimidine ring is preferably a pyrimidine-2,5-diyl group. As the divalent cyclic group, 1,4-phenylene group, 1,3-phenylene group, naphthalene-2,6-diyl group and 1,4-cyclohexylene group are particularly preferable.

F ² may have a substituent. Examples of the substituent include a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, nitro group, alkyl group having 1 to 16 carbon atoms, alkenyl group having 2 to 16 carbon atoms, carbon An alkynyl group having 2 to 16 atoms, an alkyl group substituted with a halogen atom having 1 to 16 carbon atoms, an alkoxy group having 1 to 16 carbon atoms, an acyl group having 2 to 16 carbon atoms, and 1 to 1 carbon atoms 16 alkylthio groups, acyloxy groups having 2 to 16 carbon atoms, alkoxycarbonyl groups having 2 to 16 carbon atoms, carbamoyl groups, carbamoyl groups substituted with alkyl groups having 2 to 16 carbon atoms, and 2 to 2 carbon atoms 16 acylamino groups are included. As the substituent of the divalent cyclic group, a halogen atom, a cyano group, an alkyl group having 1 to 6 carbon atoms, and an alkyl group substituted with a halogen atom having 1 to 6 carbon atoms are preferable. An alkyl group having 1 to 4 carbon atoms and an alkyl group substituted with a halogen atom having 1 to 4 carbon atoms are preferable, and a halogen atom, an alkyl group having 1 to 3 carbon atoms, and a trifluoromethyl group are more preferable.

n3 represents an integer of 1 to 3. n3 is preferably 1 or 2. When n3 is 2 or more, each F ² may be the same or different.

L ³¹ is —O—, —O—CO—, —CO—O—, —O—CO—O—, —S—, —NH—, —SO ₂ —, —CH ₂ —, —CH═CH—. , -C≡C-, and when the above group is a group containing a hydrogen atom, the hydrogen atom may be replaced by a substituent. A preferred range for L ³¹ is the same as L ^{22 in} formula (DI-R).

L ³² represents —O—, —S—, —C (═O) —, —SO ₂ —, —NH—, —CH ₂ —, —CH═CH—, —C≡C—, or two or more thereof. Represents a divalent linking group selected from the group formed by linking and when the above group is a group containing a hydrogen atom, the hydrogen atom may be replaced by a substituent. A preferred range for L ³² is the same as L ^{23 in} formula (DI-R).

Q ³ represents a polymerizable group or a hydrogen atom, and a preferred range is the same as Q ¹ in the general formula (DI-R).

  Next, the detail of the compound represented by general formula (DIII) is described.

In the general formula (DIII), Y ⁴¹ , Y ⁴² and Y ⁴³ each independently represents a methine or nitrogen atom. When Y ⁴¹ , Y ⁴² and Y ⁴³ are each methine, the hydrogen atom of the methine is a substituent. May be substituted. Examples of the substituent that methine may have include an alkyl group, an alkoxy group, an aryloxy group, an acyl group, an alkoxycarbonyl group, an acyloxy group, an acylamino group, an alkoxycarbonylamino group, an alkylthio group, an arylthio group, a halogen atom, and A cyano group can be mentioned as a preferred example. Among these substituents, an alkyl group, an alkoxy group, an alkoxycarbonyl group, an acyloxy group, a halogen atom and a cyano group are more preferable, an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, Particularly preferred are an alkoxycarbonyl group having 2 to 12 carbon atoms, an acyloxy group having 2 to 12 carbon atoms, a halogen atom and a cyano group.
Y ⁴¹ , Y ⁴² and Y ⁴³ are all preferably methine, and methine is more preferably unsubstituted.

R ⁴¹ , R ⁴² and R ⁴³ each independently represent the following general formula (DIII-A), the following general formula (DIII-B), or the following general formula (DIII-C).
In the case of producing a retardation plate or the like having a small wavelength dispersion, R ⁴¹ , R ⁴² and R ⁴³ are each preferably represented by general formula (DIII-A) or general formula (DIII-C), What is represented by general formula (DIII-A) is more preferable.

In the general formula (DIII-A), A ⁴¹ , A ⁴² , A ⁴³ , A ⁴⁴ , A ⁴⁵ and A ⁴⁶ each independently represents a methine or nitrogen atom. At least one of A ⁴¹ and A ⁴² is preferably a nitrogen atom, and more preferably both are nitrogen atoms. At least three of A ⁴³ , A ⁴⁴ , A ⁴⁵ and A ⁴⁶ are preferably methine, more preferably methine. When A ⁴³ , A ⁴⁴ , A ⁴⁵ and A ⁴⁶ are each methine, the hydrogen atom of methine may be substituted with a substituent. Examples of substituents possessed by methine include halogen atoms (fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, nitro group, alkyl group having 1 to 16 carbon atoms, and alkenyl group having 2 to 16 carbon atoms. Group, an alkynyl group having 2 to 16 carbon atoms, an alkyl group substituted with a halogen atom having 1 to 16 carbon atoms, an alkoxy group having 1 to 16 carbon atoms, an acyl group having 2 to 16 carbon atoms, a carbon atom An alkylthio group having 1 to 16 carbon atoms, an acyloxy group having 2 to 16 carbon atoms, an alkoxycarbonyl group having 2 to 16 carbon atoms, a carbamoyl group, a carbamoyl group and a carbon atom substituted with an alkyl group having 2 to 16 carbon atoms The acylamino group of several 2-16 is contained. Among these, a halogen atom, a cyano group, an alkyl group having 1 to 6 carbon atoms, and an alkyl group substituted with a halogen having 1 to 6 carbon atoms are preferable, a halogen atom, an alkyl group having 1 to 4 carbon atoms, An alkyl group substituted with a halogen having 1 to 4 carbon atoms is more preferable, and a halogen atom, an alkyl group having 1 to 3 carbon atoms, and a trifluoromethyl group are more preferable.
X ⁴¹ represents an oxygen atom, a sulfur atom, methylene or imino, and preferably an oxygen atom.

In the general formula (DIII-B), A ⁵¹ , A ⁵² , A ⁵³ , A ⁵⁴ , A ⁵⁵ and A ⁵⁶ each independently represents a methine or nitrogen atom. At least one of A ⁵¹ and A ⁵² is preferably a nitrogen atom, and more preferably both are nitrogen atoms. At least three of A ⁵³ , A ⁵⁴ , A ⁵⁵ and A ⁵⁶ are preferably methine, more preferably methine. When A ⁵³ , A ⁵⁴ , A ⁵⁵ and A ⁵⁶ are each methine, the hydrogen atom of methine may be substituted with a substituent. Examples of the substituent that methine may have include a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, nitro group, alkyl group having 1 to 16 carbon atoms, and 2 to 2 carbon atoms. 16 alkenyl groups, an alkynyl group having 2 to 16 carbon atoms, an alkyl group substituted with a halogen having 1 to 16 carbon atoms, an alkoxy group having 1 to 16 carbon atoms, an acyl group having 2 to 16 carbon atoms, An alkylthio group having 1 to 16 carbon atoms, an acyloxy group having 2 to 16 carbon atoms, an alkoxycarbonyl group having 2 to 16 carbon atoms, a carbamoyl group, a carbamoyl group substituted with an alkyl group having 2 to 16 carbon atoms, and An acylamino group having 2 to 16 carbon atoms is included. Among these, a halogen atom, a cyano group, an alkyl group having 1 to 6 carbon atoms, and an alkyl group substituted with a halogen atom having 1 to 6 carbon atoms are preferable, and a halogen atom and an alkyl group having 1 to 4 carbon atoms. An alkyl group substituted with a halogen atom having 1 to 4 carbon atoms is more preferable, and a halogen atom, an alkyl group having 1 to 3 carbon atoms, or a trifluoromethyl group is more preferable.
X ⁵² represents an oxygen atom, a sulfur atom, methylene or imino, and preferably an oxygen atom.

In the general formula (DIII-C), A ⁶¹ , A ⁶² , A ⁶³ , A ⁶⁴ , A ⁶⁵ and A ⁶⁶ each independently represents a methine or nitrogen atom. At least one of A ⁶¹ and A ⁶² is preferably a nitrogen atom, and more preferably both are nitrogen atoms. At least three of A ⁶³ , A ⁶⁴ , A ⁶⁵ and A ⁶⁶ are preferably methine, more preferably methine. When A ⁶³ , A ⁶⁴ , A ⁶⁵ and A ³⁶ are each methine, the hydrogen atom of the methine may be substituted with a substituent. Examples of the substituent that methine may have include a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), cyano group, nitro group, alkyl group having 1 to 16 carbon atoms, carbon atom number An alkenyl group having 2 to 16 carbon atoms, an alkynyl group having 2 to 16 carbon atoms, an alkyl group substituted with a halogen having 1 to 16 carbon atoms, an alkoxy group having 1 to 16 carbon atoms, and an acyl having 2 to 16 carbon atoms Group, an alkylthio group having 1 to 16 carbon atoms, an acyloxy group having 2 to 16 carbon atoms, an alkoxycarbonyl group having 2 to 16 carbon atoms, a carbamoyl group, and a carbamoyl substituted with an alkyl group having 2 to 16 carbon atoms Groups and acylamino groups of 2 to 16 carbon atoms are included. Among these, a halogen atom, a cyano group, an alkyl group having 1 to 6 carbon atoms, and an alkyl group substituted with a halogen having 1 to 6 carbon atoms are preferable, a halogen atom, an alkyl group having 1 to 4 carbon atoms, An alkyl group substituted with a halogen having 1 to 4 carbon atoms is more preferable, and a halogen atom, an alkyl group having 1 to 3 carbon atoms, and a trifluoromethyl group are more preferable.
X ⁶³ represents an oxygen atom, a sulfur atom, methylene or imino, preferably an oxygen atom.

L ^{41 in} the general formula (DIII-A), L ^{51 in} the general formula (DIII-B), and L ⁶¹ in the general formula (DIII-C) are each independently —O— or —O—CO—. , —CO—O—, —O—CO—O—, —S—, —NH—, —SO ₂ —, —CH ₂ —, —CH═CH— or —C≡C—. Preferably, -O -, - O-CO -, - CO-O -, - O-CO-O -, - CH 2 -, - CH = CH -, - it is C≡C-, more preferably, —O—, —O—CO—, —CO—O—, —O—CO—O— or —CH ₂ —. When the above group is a group containing a hydrogen atom, the hydrogen atom may be replaced with a substituent.
Examples of such a substituent include a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 6 carbon atoms, an alkyl group substituted with a halogen atom having 1 to 6 carbon atoms, and an alkoxy having 1 to 6 carbon atoms. Group, an acyl group having 2 to 6 carbon atoms, an alkylthio group having 1 to 6 carbon atoms, an acyloxy group having 2 to 6 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, a carbamoyl group, and 2 carbon atoms Preferred examples include a carbamoyl group substituted with ~ 6 alkyl and an acylamino group having 2 to 6 carbon atoms, and a halogen atom and an alkyl group having 1 to 6 carbon atoms are more preferred.

L ^{42 in} the general formula (DIII-A), L ^{52 in} the general formula (DIII-B), and L ⁶² in the general formula (DIII-C) are each independently —O—, —S—, — Selected from C (═O) —, —SO ₂ —, —NH—, —CH ₂ —, —CH═CH— and —C≡C— and groups formed by linking two or more thereof. Represents a divalent linking group. Here, the hydrogen atoms of —NH—, —CH ₂ —, and —CH═CH— may be substituted with a substituent. Examples of such a substituent include a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 6 carbon atoms, an alkyl group substituted with a halogen atom having 1 to 6 carbon atoms, and an alkoxy having 1 to 6 carbon atoms. Group, an acyl group having 2 to 6 carbon atoms, an alkylthio group having 1 to 6 carbon atoms, an acyloxy group having 2 to 6 carbon atoms, an alkoxycarbonyl group having 2 to 6 carbon atoms, a carbamoyl group, and 2 carbon atoms Preferred examples include a carbamoyl group substituted with ~ 6 alkyl and an acylamino group having 2 to 6 carbon atoms, and a halogen atom and an alkyl group having 1 to 6 carbon atoms are more preferred.

L ⁴² , L ⁵² and L ⁶² each independently connect —O—, —C (═O) —, —CH ₂ —, —CH═CH— and —C≡C— and two or more thereof. It is preferable that it is a bivalent coupling group selected from the group formed in this way. L ⁴² , L ⁵² and L ⁶² each independently preferably contain 1 to 20 carbon atoms, more preferably 2 to 14 carbon atoms. Further, L ⁴² , L ⁵² and L ⁶² each independently preferably contain 1 to 16 —CH ₂ —, and more preferably ₂ to 12 —CH ₂ —.

Formula (DIII-A) in Q ^4, the general formula (DIII-B) Q ⁵ and formula in (DIII-C) Q ⁶ in each independently represents a polymerizable group or a hydrogen atom . These preferable ranges are the same as Q < ¹ > in general formula (DI-R).

  Although the specific example of a compound represented by general formula (DI), general formula (DII), and general formula (DIII) below is shown, this invention is not limited to these.

  The compounds represented by formula (DIII) are shown below.

  The compounds represented by the above general formula (DI), general formula (DII) and general formula (DIII) used in the present invention can be synthesized by applying known methods.

  In the present invention, as the liquid crystalline compound, only one of the compounds represented by the above general formula (DI), general formula (DII) and general formula (DIII) may be used, or two or more kinds thereof may be used. Also good. The compounds represented by the general formulas (DI) to (DIII) are characterized by low birefringence wavelength dispersion when they exhibit birefringence due to their orientation. Therefore, for example, when an optically anisotropic film or the like is produced using the compound, if the optical characteristics of G light that is an intermediate wavelength in the visible light region are optimized, R light and B light can also be obtained. Since the optical characteristics are optimized in substantially the same manner, by using such a liquid crystal compound, an optical anisotropic film or the like that exhibits desired optical characteristics over the entire visible light range can be easily manufactured. Further, the compounds represented by the general formulas (DI) to (DIII) are compounds that are difficult to be hybrid-aligned at a low average tilt angle (for example, an average tilt angle of 40 ° or less), but in the presence of the polymer. In this way, a hybrid alignment state with a low average tilt angle and no alignment defects (or reduced) is obtained.

  Furthermore, you may use together the rod-shaped liquid crystalline compound or discotic liquid crystalline compound which has a structure different from the compound represented by general formula (DI), general formula (DII), and general formula (DIII) with at least 1 type or more. The combined use with the discotic liquid crystalline compound which does not belong to the general formula (DI), the general formula (DII) and the general formula (DIII) is particularly preferable, and the combined use with the liquid crystalline compound represented by the following general formula (T) Is more preferable. By using two or more types of discotic liquid crystal compounds in combination, the tilt angle at the air interface can be further reduced, and the temperature dependency of the average tilt angle can be easily relaxed.

In general formula (T), M is a bivalent coupling group, and may be the same or different. Q ⁷ represents a polymerizable group or a hydrogen atom, and may be the same or different.

  In the above formula, the divalent linking group (M) is a divalent group selected from the group consisting of an alkylene group, an alkenylene group, an arylene group, —CO—, —NH—, —O—, —S—, and combinations thereof. The linking group is preferably. The divalent linking group (M) is a combination of 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—. More preferably, it is a group. 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 number of carbon atoms of the alkylene group is preferably 1 to 12, more preferably 2 to 12, and still more preferably 6 to 10. The alkylene group, alkenylene group and arylene group may have a substituent (for example, an alkyl group, a halogen atom, a cyano, an alkoxy group, an acyloxy group). Examples of the divalent linking group (M) are shown below. The left side is bonded to the triphenylene disc core (TD), and the right side is bonded to the polymerizable group (Q). 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-OC
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-

Q ⁷ represents a polymerizable group or a hydrogen atom, and a preferred range is synonymous with Q ¹ in the general formula (DI-R), and a preferred range is also synonymous.

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

  The compound represented by formula (T) used in the present invention can be synthesized using a known method.

  As for the liquid crystalline compound used in the present invention, the addition range of the compound represented by the general formula (T) is as compared with the compounds represented by the general formula (DI), the general formula (DII) and the general formula (DIII). , Preferably it is 1-20 mass%, More preferably, it is 3-20 mass%, More preferably, it is 5-15 mass%.

  The liquid crystal compound used in the present invention desirably exhibits a liquid crystal phase exhibiting good monodomain properties. By making the monodomain property favorable, it is possible to effectively prevent the resulting structure from becoming a polydomain, causing an alignment defect at the boundary between domains, and scattering light. Furthermore, it is preferable to exhibit good monodomain properties because the retardation plate has a higher light transmittance.

  Examples of the liquid crystal phase exhibited by the liquid crystalline compound used in the present invention include a columnar phase and a discotic nematic phase (ND phase). Among these liquid crystal phases, a discotic nematic phase (ND phase) that exhibits good monodomain properties and can be hybrid-aligned is particularly preferable.

  The liquid crystalline compound used in the present invention is better as the anisotropic wavelength dispersion is smaller. Specifically, Re (450) / Re (650) is 1.25, where Re (λ) is the retardation (in-plane retardation value (nm) of the liquid crystal layer at wavelength λ) that the liquid crystalline compound develops. Is preferably less than 1.20, more preferably 1.20 or less, and particularly preferably 1.15 or less.

In order to align the liquid crystal compound used in the present invention on an alignment film provided on a support, the isotropic phase transition temperature T _iso (° C.) is preferably 100 <T _iso <180, and 100 < T _iso ≦ 165 ° C. is more preferable, and 100 <T _iso ≦ 150 ° C. is particularly preferable.
Further, the liquid crystal compound used in the present invention preferably satisfies 0 <| Re ( _Tiso- 50) -Re ( _Tiso- 30) | <10.
Here, the isotropic phase transition temperature of a liquid crystal compound is a state in which there is no alignment order from a temperature at which single or mixture of liquid crystal molecules exhibiting liquid crystallinity is aligned in a certain direction (so-called liquid crystal state). The temperature at which switching to a so-called isotropic state is shown.
This isotropic phase transition temperature can be determined by texture observation with a polarizing microscope. For example, a liquid crystal compound is placed on a glass plate and observed with a polarizing microscope while heating. From a liquid crystal state in which the visual field is bright to a liquid state (a state that is optically isotropic) that appears to be dark. The temperature at the time of transition was taken.

In the hybrid alignment, the angle between the physical symmetry axis of the liquid crystalline compound of the present invention and the surface of the second optically anisotropic layer, which will be described later, that is, the tilt angle is the depth of the second optically anisotropic layer. It increases or decreases with increasing (that is, the direction perpendicular to the second optical anisotropic layer and the distance from the surface of the polarizing film).
Preferably, the tilt angle decreases with increasing distance. Further, the change in the tilt angle can be continuous increase, continuous decrease, intermittent increase, intermittent decrease, change including continuous increase and continuous decrease, or intermittent change including increase and decrease. . The intermittent change includes a region where the inclination angle does not change in the middle of the thickness direction. Even if a region where the angle does not change is included, it may be increased or decreased as a whole. However, it is preferred that the tilt angle changes continuously.

In general, the average direction of the physical symmetry axis of a discotic liquid crystalline compound can be adjusted by selecting the type of discotic liquid crystalline compound or alignment film, or by selecting a rubbing treatment method. it can. Also, the physical symmetry axis direction of the surface side (air side) discotic liquid crystalline compound is generally adjusted by selecting the discotic liquid crystalline compound or the type of additive used together with the discotic liquid crystalline compound. Can do.
Examples of the additive used together with the discotic liquid crystalline compound include a plasticizer, a surfactant, a polymerizable monomer, a polymer, and a low molecular compound. The degree of change in the orientation direction of the long axis can be adjusted by selecting the liquid crystalline compound and the additive as described above.

  The plasticizer and polymerizable monomer used together with the liquid crystalline compound of the present invention are compatible with the liquid crystalline compound of the present invention and can change the tilt angle of the discotic liquid crystalline compound or do not inhibit the alignment. Things are adopted.

一般式（Ａ）中、Ｍｐはポリマー主鎖の一部を構成する３価の基を表し、Ｌは単結合又は２価の連結基を表し、Ｘは置換もしくは無置換の芳香族縮合環官能基を表す。 [polymer]
The optically anisotropic layer includes at least one liquid crystalline compound, a polymer including a structural unit represented by the following general formula (A) and a structural unit derived from a fluoroaliphatic group-containing monomer (hereinafter referred to as “the present invention”). It is preferably formed from a liquid crystal composition containing at least one kind of “polymer used in”. The polymer used in the present invention contributes to a liquid crystal molecule, particularly a discotic liquid crystal molecule, in a hybrid alignment state at a low tilt angle. Further, the tilt angle is unlikely to change due to temperature fluctuations. Therefore, by using the polymer, an optically anisotropic film or the like exhibiting desired optical characteristics can be stably produced. Moreover, by containing the polymer in the liquid crystal composition, it is possible to suppress the occurrence of fine irregularities having a diameter of submicron to micron order and a depth of nanometer order on the film surface formed by coating, Since the coating properties of the coating liquid are improved, visible irregularities (such as film thickness irregularities that occur when the coating liquid is dried) that are larger than the fine irregularities (for example, centimeter to metric order) are generated. It can also be reduced.
Below, the polymer used by this invention is demonstrated.
(1) Structural unit represented by general formula (A)

In general formula (A), Mp represents a trivalent group constituting a part of the polymer main chain, L represents a single bond or a divalent linking group, and X represents a substituted or unsubstituted aromatic condensed ring function. Represents a group.

  In general formula (A), Mp is a trivalent group and constitutes a part of the main chain of the polymer. Mp is preferably a substituted or unsubstituted long chain or branched alkylene group having 2 to 20 carbon atoms (not including the number of carbon atoms in the substituent, hereinafter the same for those in Mp) (for example, an ethylene group). , Propylene group, methylethylene group, butylene group, hexylene group, etc.), substituted or unsubstituted cyclic alkylene group having 3 to 10 carbon atoms (for example, cyclopropylene group, cyclobutylene group, cyclohexylene group, etc.), substituted or An unsubstituted vinylene group, a substituted or unsubstituted cyclic vinylene group, a substituted or unsubstituted phenylene group, a group containing an oxygen atom (for example, a group containing an ether group, an acetal group, an ester group, a carbonate group, etc.), a nitrogen atom (For example, amino group, imino group, amide group, urethane group, ureido group, imide group, imidazole group, oxy group) A group containing a sol group, a pyrrole group, an anilide group, a maleimide group, etc.), a group containing a sulfur atom (eg, a group containing a sulfide group, a sulfone group, a thiophene group, etc.), a group containing a phosphorus atom (eg, a phosphine group) A group containing a phosphoric acid ester group), a group containing a silicon atom (for example, a group containing a siloxane group, etc.), and a group formed by linking two or more of these groups, Is preferably a group in which one of the hydrogen atoms contained in is substituted by an -L-X group, more preferably a substituted or unsubstituted ethylene group, a substituted or unsubstituted methylethylene group, a substituted or unsubstituted cyclohexylene. A group, a substituted or unsubstituted vinylene group in which one of the hydrogen atoms contained in the group is substituted by an -L-X group, and more preferably a substituted or unsubstituted vinylene group; An unsubstituted ethylene group, a substituted or unsubstituted methylethylene group, a substituted or unsubstituted vinylene group, wherein one of the hydrogen atoms contained in the group is substituted by an -LX group; Particularly preferably, it is a substituted or unsubstituted ethylene group, a substituted or unsubstituted methylethylene group, wherein one of the hydrogen atoms contained in the group is substituted by an -L-X group, Mp-1 and Mp-2 described later are preferable.

  Although the preferable specific example of Mp is shown below, Mp is not limited to this. Moreover, the site | part represented by * in Mp represents the site | part connected with L. FIG.

The divalent linking group represented by L in the general formula (A) is preferably a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms (for example, methylene group, ethylene group, propylene group, butylene). Group, isopropylene group, etc.), alkenylene group having 2 to 20 carbon atoms (for example, vinylene group, butene group, etc.), -O-, -NR ^a1- , -S-, ^{-PR a2-} , -Si (R ^a3 ) (R ^a4 )-, -C (= O)-, -C (= O) O-, -C (= O) NR ^a5- , -OC (= O) O-, -OC (= O) NR ^a6 —, —NR ^a7 C (═O) NR ^a8 —, — (— O) ₂ CH— and a divalent linking group selected from a group formed by linking two or more thereof.
Here, R ^{a1 to} R ^a8 represent a substitutable substituent, for example, a hydrogen atom, a halogen atom, an alkyl group (a cycloalkyl group such as a monocycloalkyl group or a bicycloalkyl group containing one or more ring structures). Alkenyl group (including cycloalkenyl group and bicycloalkenyl group), alkynyl group, cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, silyloxy group, acyloxy group, alkoxycarbonyloxy group, amino group (anilino) Group), acylamino group, aminocarbonylamino group, alkoxycarbonylamino group, mercapto group, alkylthio group, sulfamoyl group, sulfo group, alkylsulfinyl group, alkylsulfonyl group, acyl group, alkoxycarbonyl group, imido group, phosphino group Phosphinyl group Examples thereof include phosphinyloxy group, phosphinylamino group and silyl group, and a hydrogen atom and an alkyl group are preferable.

More preferably, L in the general formula (A) is —O—, —NR ^a11 — (wherein R ^a11 represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 10 carbon atoms), —S—, Selected from —C (═O) —, —S (═O) ₂ —, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and a group formed by linking two or more thereof. In particular, —C (═O) O—, —OC (═O) —, —O—, —OC (═O) O—, —C (═O) NH—. , —NHC (═O) —, —C (═O) O (CH ₂ ) _m O—, — (CH ₂ ) m—, and a group formed by linking two or more thereof. A divalent linking group is preferred.
Here, m represents an integer of 1 to 20. m is preferably 1 to 16, more preferably 2 to 12, and further preferably 2 to 6, in order to appropriately adjust the degree of freedom of X. By appropriately adjusting the degree of freedom of X, the interaction with the liquid crystal to be aligned increases, the X direction can be more controlled, and the average tilt angle can be controlled more effectively.
In addition, the following linking groups formed by linking two or more of the above linking groups are also preferable. Moreover, the site | part represented by * in L represents the site | part connected with Mp. In the following formula, m represents an integer of 1 to 20, has the same meaning as the above “m”, and the preferred range is also the same.

Further, when Mp in the general formula (A) represents Mp-1 or Mp-2, L represents —O—, —NR ^a11 — (R ^a11 represents a hydrogen atom, a carbon atom number of 1 to 10 Aliphatic hydrocarbon group), -S-, -C (= O)-, -S (= O) _2- , and a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and these It is preferably a divalent linking group selected from a group formed by linking two or more, -O-, -C (= O) O-, and -C (= O) NH-, In addition, a group selected from divalent linking groups composed of a combination of one or more of these and an alkylene group is more preferable. For example, the L-1, L-2, L-3, L-6 and the like.

  Although there is no restriction | limiting in particular about the ring number of the substituted or unsubstituted aromatic condensed ring functional group represented by X in General formula (A), It is preferable that it is the group which 2-5 rings condensed. Not only a hydrocarbon aromatic condensed ring in which the atoms constituting the ring are only carbon atoms, but also an aromatic condensed ring in which a hetero ring having a hetero atom as a ring constituent atom is condensed. X is a substituted or unsubstituted indenyl group having 5 to 30 carbon atoms (methylindenyl group, medoxyindenyl group, or indenyl group substituted with a heteroatom, for example, benzofuranyl group, thionaphthenyl group, indolenyl group , Indazolenyl group, benzimidazolyl group, benzotriazolenyl group, 1-pyrazolepyrazinyl group, etc.), substituted or unsubstituted naphthyl group having 6 to 30 carbon atoms (methylnaphthyl group, cyanonaphthyl group, fluoronaphthyl group) Group, bromonaphthyl group, or naphthyl group substituted with a hetero atom, for example, quinolyl group, isoquinolyl group, quinazolyl group, quinoxalyl group, 6,7-pyridopyridazinyl group, benzotetrazinyl group, pteryl group Etc.), substituted or unsubstituted fluorenyl group having 12 to 30 carbon atoms 2,7-dimethylfluorenyl group, or a fluorenyl group substituted with a heteroatom, such as carbazolyl group, dibenzofuryl group, dibenzothiophenyl group, etc.), anthryl group (5-methylanthryl group, or heteroatom) Anthryl group substituted with, for example, xanthenyl group, acridinyl group, phenazinyl group, etc.), pyrenyl group, perylenyl group, phenanthrenyl group, and the like.

  In general formula (A), X is more preferably a substituted or unsubstituted indenyl group having 5 to 30 carbon atoms, or a substituted or unsubstituted naphthyl group having 6 to 30 carbon atoms, and more preferably A substituted or unsubstituted naphthyl group having 10 to 30 carbon atoms, particularly preferably a substituted or unsubstituted naphthyl group having 10 to 20 carbon atoms.

In particular, L is a single bond, or —O—, —NR ^a11 — (where R ^a11 is a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms), —S—, —C (═O) —. , And —S (═O) ₂ — and a divalent linking group selected from a group formed by linking two or more of these, X is a substituted or unsubstituted naphthyl group Is preferably represented.

  Specific examples of preferred structural units as general formula (A) are shown below, but the present invention is not limited thereto.

(2) Structural unit derived from fluoroaliphatic group-containing monomer The polymer used in the present invention has a structural unit derived from a fluoroaliphatic group-containing monomer together with the structural unit represented by the general formula (A). . The structural unit is preferably a structural unit represented by the following general formula (B). The detail about group represented by general formula (B) below is described.

  In general formula (B), Mp ′ represents a trivalent group constituting the main chain of the polymer, L ′ represents a single bond or a divalent linking group, and Rf represents a substituent containing at least one fluorine atom. Represents.

Mp ′ is synonymous with Mp in the general formula (A), and a preferred range is also synonymous.
L ′ is preferably —O—, —NR ^a11 — (wherein R ^a11 represents a hydrogen atom, an aliphatic hydrocarbon group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms). , —S—, —C (═O) —, —S (═O) ₂ —, a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and a combination of two or more thereof. It is a divalent linking group selected from the following groups.
Examples of the divalent linking group formed by linking two or more include -C (= O) O-, -OC (= O)-, -OC (= O) O-, -C (= O) NH. -, - NHC (= O) -, - C (= O) O (CH 2) ma O- ( where, ma is an integer of 1 to 20), and the like.

Further, when Mp ′ in the general formula (B) represents Mp-1 or Mp-2, L ′ represents —O—, —NR ^a11 — (R ^a11 represents a hydrogen atom, 1 carbon atom. -S-, -C (= O)-, -S (= O) _2- , and a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms. And a divalent linking group selected from a group formed by linking two or more of these, -O-, -C (= O) O-, and -C (= O) NH— and a divalent linking group selected from a group consisting of one or more of these and an alkylene group (for example, L-1, L-2, L-3 and the like) are more preferable.

Rf represents an aliphatic hydrocarbon group having 1 to 30 carbon atoms substituted with at least one fluorine atom (for example, trifluoroethyl group, perfluorohexylethyl group, perfluorohexylpropyl group, perfluorobutylethyl group, perfluorobutyl group, Preferred examples include a fluorooctylethyl group and the like. Rf preferably has a CF ₃ group or a CF ₂ H group at the terminal, and more preferably has a CF ₃ group.

Rf is more preferably an alkyl group having a CF ₃ group at the terminal or an alkyl group having a CF ₂ H group at the terminal. The alkyl group having a CF ₃ 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. An alkyl group in which 50% or more of the hydrogen atoms in the alkyl group having a CF ₃ group at the terminal are substituted with fluorine atoms is preferred, an alkyl group in which 60% or more is substituted is more preferred, and 70% or more is substituted. Particularly preferred are alkyl groups. 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 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 the hydrogen atoms in the alkyl group having a CF ₂ H group at the terminal are preferably substituted with fluorine atoms, more preferably 60% or more are substituted, and 70% or more are substituted. It is particularly preferable. The remaining hydrogen atoms may be further substituted with the substituents exemplified as the substituent group D described later.

Substituent group D
An alkyl group (preferably having 1 to 20 carbon atoms (referring to the substituent group D hereinafter), more preferably 1 to 12 carbon atoms, particularly preferably 1 carbon atom. ~ 8 alkyl groups, for example, 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. An alkenyl group (preferably an alkenyl group having 2 to 20 carbon atoms, more preferably 2 to 12 carbon atoms, and particularly preferably 2 to 8 carbon atoms, such as a vinyl group or a 2-butenyl group). , 3-pentenyl groups, etc.), alkynyl groups (preferably 2-20 carbon atoms, more preferably 2-12 carbon atoms, particularly preferred) Is an alkynyl group having 2 to 8 carbon atoms, and examples thereof include a propargyl group and 3-pentynyl group, and a substituted or unsubstituted amino group (preferably having 0 to 20 carbon atoms, more preferably carbon atoms). An amino group having 0 to 10, particularly preferably 0 to 6 carbon atoms, and examples thereof include an unsubstituted amino group, a methylamino group, a dimethylamino group, and a diethylamino group).

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 acyl group (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as an acetyl group, a formyl group, a pivaloyl group, etc. An alkoxycarbonyl group (preferably an alkoxycarbonyl group having 2 to 20 carbon atoms, more preferably 2 to 16 carbon atoms, particularly preferably 2 to 12 carbon atoms, such as a methoxycarbonyl group, An ethoxycarbonyl group), an acyloxy group (preferably having 2 to 20 carbon atoms, more preferably a carbon atom) Number 2 to 16, particularly preferably an acyloxy group having 2 to 10 carbon atoms, such as acetoxy 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), alkoxycarbonylamino A 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), A sulfonylamino group (preferably a sulfonylamino group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, such as a methanesulfonylamino group and an ethanesulfonylamino group. ), A sulfamoyl group (preferably having 0 to 20 carbon atoms, Ri preferably 0 to 16 carbon atoms, particularly preferably a sulfamoyl group having 0 to 12 carbon atoms, e.g., sulfamoyl group, methylsulfamoyl group, dimethylsulfamoyl group).

  An alkylthio group (preferably an alkylthio group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include a methylthio group and an ethylthio group). A sulfonyl group (preferably a sulfonyl group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include a mesyl group and a tosyl group). A sulfinyl group (preferably a sulfinyl group having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, particularly preferably 1 to 12 carbon atoms, and examples thereof include a methanesulfinyl group and an ethanesulfinyl group. ), Ureido groups (preferably having 1 to 20 carbon atoms, more preferably 1 to 16 carbon atoms, and particularly preferably carbon A ureido group having 1 to 12 atoms, such as an unsubstituted ureido group and a methylureido group, and a phosphoric acid amide group (preferably having 1 to 20 carbon atoms, more preferably 1 to 1 carbon atom). 16, particularly preferably a phosphoric acid amide group having 1 to 12 carbon atoms, such as a diethylphosphoric acid amide group, a hydroxy group, a mercapto group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, iodine) Atom), cyano group, sulfo group, carboxyl group, nitro group, hydroxamic acid group, sulfino group, hydrazino group, imino group, silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms). And particularly preferably a silyl group having 3 to 24 carbon atoms, such as a trimethylsilyl 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.

Examples of an alkyl group having a CF ₃ group at the terminal 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) 3 -
_{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) 2 -
R11: H— (CF ₂ ) ₆ — (CH ₂ ) ₃ —
R12: H— (CF ₂ ) ₄ — (CH ₂ ) ₂ —
_{R13: n-C 7 F 15} - (CH 2) 2 -
_{R14: n-C 6 F 13} - (CH 2) 3 -
_{R15: n-C 4 F 9} - (CH 2) 2 -

  Specific examples of structural units derived from the fluoroaliphatic group-containing monomer used in the present invention are shown below, but the present invention is not limited thereto.

The polymer used in the present invention forms these structural units in addition to the structural unit containing the structure represented by the general formula (A) and the structural unit derived from the fluoroaliphatic group-containing monomer. You may contain the structural unit induced | guided | derived from the monomer copolymerizable with a monomer.
The copolymerizable monomer is not particularly limited as long as it does not depart from the spirit of the present invention. Preferred monomers include, for example, hydrocarbon polymers (for example, polyethylene, polypropylene, polystyrene, polymaleimide, polyacrylic acid, polyacrylic acid ester, polyacrylamide, polyacrylanilide, etc.), polyether, polyester, polycarbonate Monomers constituting polyamide, polyamic acid, polyimide, polyurethane and polyureide can be preferably used from the viewpoint of improving solubility in a solvent or preventing aggregation of the polymer.
Furthermore, the structural unit whose main chain structure becomes the same as what the group represented by general formula (A) comprises is preferable.

  Specific examples of the copolymerizable structural unit are shown below, but the present invention is not limited to the following specific examples. In particular, C-2, C-3, C-10, C-11, C-12, and C-19 are preferable, and C-11 and C-19 are more preferable.

As content rate of group represented by general formula (A) in the polymer used by this invention, 1-90 mass% is preferable, and 3-80 mass% is more preferable.
The content of the repeating unit derived from the fluoroaliphatic group-containing monomer in the polymer used in the present invention (preferably a group represented by the general formula (B)) is preferably 5 to 90% by mass, and 10 to 80%. % Is more preferable.
As a content rate of structural units other than said 2 types, 60 mass% or less is preferable, and 50 mass% or less is more preferable.
For example, when the group represented by the general formula (B) contained in the polymer is (B-3), the content is preferably 20 to 50% by mass, and preferably 25 to 40% by mass. Is more preferable, and it is most preferable that it is 27-38 mass%.

These copolymers may be random copolymers in which each constituent unit is introduced irregularly, or may be block copolymers introduced regularly. Each structural unit in a certain case may be synthesized in any order of introduction, and the same structural component may be used twice or more.
Moreover, the group represented by general formula (A), the group represented by general formula (B), etc. may be only one type, and may be two or more types. When two or more structural units of the general formula (A) are contained, X is preferably the same fused ring skeleton (a combination of substituted and unsubstituted). In the case of two or more types, the content is a total content.
For example, you may have two types of (B-1) and (B-3) as group represented by general formula (B) contained in a polymer. The total content is preferably 20 to 60% by mass, more preferably 25 to 55% by mass, and still more preferably 30 to 50% by mass.

  Furthermore, the molecular weight range of the polymer used by this invention is a number average molecular weight (Mn), Preferably it is 1000-1 million, More preferably, it is 3000-200000, More preferably, it is 5000-100,000. Further, the molecular weight distribution (Mw / Mn, Mw is the weight average molecular weight) of the polymer used in the present invention is preferably 1 to 4, and more preferably 1.5 to 4.

  The addition amount range of the polymer used in the present invention is preferably 0.01 to 10% by mass, more preferably 0.1 to 5.0% by mass, and still more preferably, with respect to the liquid crystal compound. 0.5 to 2.5% by mass.

  Specific examples preferable as the polymer of the present invention are shown in Table 1 below.

  Only one type of polymer may be used, or two or more types may be used. When two or more types are used, it is preferable that one or both of the groups represented by the general formula (A) and the general formula (B) are included in common as a structural unit. For example, since the compounds in Table 1 all contain A-6 in common, two or more types can be preferably used in combination. AD-1 and AD-5, or AD-8 and AD-9 are the most preferable combination because they contain A-6 and B-3 in common and the composition ratio of B-3 is the same. .

  The synthesis of the polymer used in the present invention can be performed by applying a known method. The polymer used in the present invention can be synthesized by any combination of addition, condensation, and substitution reactions. Although there is no particular limitation, when the polymer used in the present invention contains an ethylenic repeating unit, it is convenient and preferable to synthesize using a radical polymerization reaction of an ethylenically unsaturated compound corresponding to the repeating unit.

The first optically anisotropic layer is formed by applying a coating liquid containing a discotic liquid crystalline compound, the polymer, and, if necessary, a polymerizable initiator and an optional component described later on the alignment film. it can.
The solvent used for preparing the coating solution is preferably an organic solvent. Examples of organic solvents include amides (eg N, N-dimethylformamide), sulfoxides (eg dimethyl sulfoxide), heterocyclic compounds (eg pyridine), hydrocarbons (eg benzene, hexane), alkyl halides (eg , Chloroform, dichloromethane, tetrachloroethane), esters (eg, methyl acetate, butyl acetate), ketones (eg, acetone, methyl ethyl ketone), ethers (eg, tetrahydrofuran, 1,2-dimethoxyethane). 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 (for example, a wire bar coating method, an extrusion coating method, a direct gravure coating method, a reverse gravure coating method, or a die coating method).

  The thickness of the first optically anisotropic layer is preferably 0.1 to 20 μm, more preferably 0.3 to 10 μm, and still more preferably 0.5 to 5 μm.

The aligned discotic liquid crystalline compound can be fixed while maintaining the alignment state. The immobilization is preferably performed by a polymerization reaction. The polymerization reaction includes a thermal polymerization reaction using a thermal polymerization initiator and a photopolymerization reaction using a photopolymerization initiator. Of these, the photopolymerization reaction is preferred.
Examples of the photopolymerization initiator 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 A hydrocarbon-substituted aromatic acyloin compound (described in US Pat. No. 2,722,512), a polynuclear quinone compound (described in US Pat. Nos. 3,046,127 and 2,951,758), a triarylimidazole dimer, p- Combinations with aminophenyl ketones (described in US Pat. No. 3,549,367), acridine and phenazine compounds (described in JP-A-60-105667, and US Pat. No. 4,239,850), and oxadiazole compounds ( U.S. Pat. No. 4,221,970).

The amount of the photopolymerization initiator used is preferably in the range of 0.01 to 20% by mass, more preferably in the range of 0.5 to 5% by mass, based on the solid content of the coating solution.
Light irradiation for the polymerization of the liquid crystalline compound is preferably performed using ultraviolet rays.
The irradiation energy is preferably 20~50J / cm ^2, more preferably 20~5,000mJ / cm ^2, more preferably 100 to 800 mJ / cm ^2. In order to accelerate the photopolymerization reaction, light irradiation may be performed under heating conditions.
A protective layer may be provided on the first optical anisotropic layer.

<Second optically anisotropic layer>
The optical compensation film of the present invention preferably has a second optical anisotropic layer exhibiting optical anisotropy in addition to the first optical anisotropic layer.
The second optically anisotropic layer functions as a support for the first optically anisotropic layer, and expands the control range of the optical characteristics as an optical compensation film, thereby improving the display characteristics of the liquid crystal display device. Have That is, the second optically anisotropic layer can be regarded as the above-mentioned “support” having optical anisotropy.
The second optically anisotropic layer in the present invention is composed of at least one polymer film. Here, the term “consisting of a polymer film” may include other substances in a range not departing from the gist of the present invention, in addition to those composed only of a polymer. That is, it is intended to include a film mainly composed of a polymer.
Specifically, the second optically anisotropic layer preferably has an Rth value measured with light having a wavelength of 550 nm in the range of 40 to 300 nm, and more preferably 60 to 200 nm.
The Re value of the second optically anisotropic layer is preferably 0 to 200 nm, more preferably 3 to 100 nm. By adopting such Rth value and Re value, there is an advantage that display characteristics such as viewing angle characteristics as a liquid crystal display device are improved.
The polymer film constituting the second optical anisotropic layer may be one sheet or two or more sheets. However, the Re value and the Rth value can be realized by a single polymer film. Therefore, the second optically anisotropic layer is preferably composed of one polymer film.

The polymer employed in the second optical anisotropic layer is preferably a cellulose polymer, more preferably a cellulose ester, and more preferably cellulose acylate. By employing cellulose acylate, there is an advantage that the optical characteristics as described above can be controlled.
In particular, a lower fatty acid ester of cellulose is preferable. Lower fatty acid means a fatty acid having 6 or less carbon atoms. A cellulose acylate having 2 to 4 carbon atoms is preferred, and cellulose acetate is more preferred. Mixed fatty acid esters such as cellulose acetate propionate and cellulose acetate butyrate may be used.

  The viscosity average degree of polymerization (DP) of cellulose acetate is preferably 250 or more, and more preferably 290 or more. Cellulose acetate preferably has a narrow molecular weight distribution of Mw / Mn (Mw is a mass average molecular weight, Mn is a number average molecular weight) by gel permeation chromatography. The specific value of Mw / Mn is preferably 1.00 to 1.70, more preferably 1.30 to 1.65, and particularly preferably 1.40 to 1.60. .

The acetylation degree of cellulose acetate is preferably 55.0 to 62.5%, more preferably 57.0 to 62.0%. The degree of acetylation means the amount of bound acetic acid per unit mass of cellulose. The degree of acetylation is determined by measurement and calculation of the degree of acetylation in ASTM: D-817-91 (test method for cellulose acetate and the like).
In cellulose acetate, the hydroxyl groups at the 2-position, 3-position and 6-position of cellulose are not evenly substituted, but the substitution degree at the 6-position tends to be small. In the cellulose acetate in the second optically anisotropic layer, it is preferable that the degree of substitution at the 6-position of cellulose is the same or greater than that at the 2- and 3-positions.
The ratio of the substitution degree at the 6-position to the total substitution degree at the 2-position, the 3-position, and the 6-position is preferably 30 to 40%, more preferably 31 to 40%, and more preferably 32 to 40%. More preferably it is. The substitution degree at the 6-position is preferably 0.88 or more.
As the cellulose acylate and the synthesis method thereof, for example, the method described in JIII Journal of Technical Disclosure (Publication No. 2001-1745, page 9, published on March 15, 2001, Japan Society of Invention) can be adopted.

In order to adjust the retardation of cellulose acetate, a method of applying an external force such as stretching can be given as an example. A retardation increasing agent may be added to adjust the optical anisotropy. The retardation increasing agent is preferably an aromatic compound having at least two aromatic rings. The aromatic compound is preferably used in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of the polymer. Two or more aromatic compounds may be used in combination. The aromatic ring of the aromatic compound includes an aromatic hetero ring in addition to the aromatic hydrocarbon ring.
Regarding the retardation increasing agent, the retardation increasing agents described in European Patent Application No. 0911656, JP-A 2000-1111914, and JP-A 2000-275434 can be preferably used.

The hygroscopic expansion coefficient of the cellulose acetate film is preferably 30 × 10 ⁻⁵ /% RH or less, more preferably 15 × 10 ⁻⁵ /% RH or less, and still more preferably 10 × 10 ⁻⁵ /% RH or less.
A smaller hygroscopic expansion coefficient is preferable, but usually a value of 1.0 × 10 ⁻⁵ /% RH or more is obtained. The hygroscopic expansion coefficient indicates the amount of change in the length of the sample when the relative humidity is changed at a constant temperature. By adjusting the hygroscopic expansion coefficient, it is possible to prevent a frame-like transmittance increase (light leakage due to distortion) while maintaining the optical compensation function of the optical compensation film.
In measuring the hygroscopic expansion coefficient, first, a sample having a width of 5 mm and a length of 20 mm is cut out from the polymer film, one end is fixed, and the sample is hung in an atmosphere of 25 ° C. and 20% RH (R ₀ ).
A weight of 0.5 g is hung on the other end, left for 10 minutes, and the length (L ₀ ) is measured. Next, with the temperature kept at 25 ° C., the humidity is set to 80% RH (R ₁ ), and the length (L ₁ ) is measured. The hygroscopic expansion coefficient is calculated by the following formula. The measurement is performed with 10 samples for the same sample, and an average value is adopted.
[Formula] Hygroscopic expansion coefficient [/% RH] = {(L ₁ −L ₀ ) / L ₀ } / (R ₁ −R ₀ )

In order to reduce the dimensional change due to moisture absorption of the cellulose acetate film, it is preferable to add a hydrophobic compound. The hydrophobic compound may be in the form of fine particles.
The hydrophobic compound is preferably selected from a plasticizer or a deterioration inhibitor. The hydrophobic compound preferably has a hydrocarbon group (aliphatic group or aromatic group) as a hydrophobic group.
The addition amount of the hydrophobic compound is preferably 0.01 to 10% by mass of the polymer solution (dope) to be prepared.
In order to reduce the dimensional change due to moisture absorption of the polymer film, a method of reducing the free volume in the polymer film is also effective. For example, if the amount of residual solvent in the solvent casting method described later is reduced, the free volume is reduced. It is preferable to dry the polymer film under the condition that the residual solvent amount with respect to the polymer film is 0.01 to 1.00% by mass.

Examples of polymer film additives include UV inhibitors, release agents, antistatic agents, degradation inhibitors (eg, antioxidants, peroxide decomposers, radical inhibitors, metal deactivators, acid scavengers). , Amine), and an infrared absorber.
When the polymer film is formed from multiple layers, the type and amount of additive in each layer may be different. About an additive, it is described in an invention association public technical bulletin (public technical number 2001-1745, 16-22 pages, March 15, 2001 issue, invention association). The amount of additive used is generally in the range of 0.001 to 25% by weight of the polymer film.

The cellulose acetate film is preferably produced by a solvent cast method. In the solvent cast method, a film is produced using a solution (dope) in which a polymer material is dissolved in an organic solvent.
The organic solvent is a solvent selected from ethers having 3 to 12 carbon atoms, ketones having 3 to 12 carbon atoms, esters having 3 to 12 carbon atoms, and halogenated hydrocarbons having 1 to 6 carbon atoms. It is preferable to contain. The ether, ketone and ester may have a cyclic structure. A compound having two or more functional groups of ether, ketone, and ester (that is, —O—, —CO—, and COO—) can also be used as the organic solvent.
The organic solvent may have another functional group such as an alcoholic hydroxyl group. In the case of an organic solvent having two or more types of functional groups, the number of carbon atoms may be within the specified range of the compound having any functional group.

Examples of the ether having 3 to 12 carbon atoms include diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, tetrahydrofuran, anisole, and phenetole. Examples of ketones having 3 to 12 carbon atoms include acetone, methyl ethyl ketone, diethyl ketone, diisobutyl ketone, cyclohexanone and methylcyclohexanone. Examples of the esters having 3 to 12 carbon atoms include ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate and pentyl acetate.
Examples of the organic solvent having two or more kinds of functional groups include 2-ethoxyethyl acetate, 2-methoxyethanol, and 2-butoxyethanol. The number of carbon atoms of the halogenated hydrocarbon is preferably 1 or 2, and more preferably 1. The halogen of the halogenated hydrocarbon is preferably chlorine. The proportion of halogen atoms in the halogenated hydrocarbon substituted with halogen is preferably 25 to 75 mol%, more preferably 30 to 70 mol%, still more preferably 35 to 65 mol%, It is especially preferable that it is 40-60 mol%. Methylene chloride is a typical halogenated hydrocarbon. Two or more organic solvents may be mixed and used.

A cellulose acetate solution can be prepared by a general method. In a general method, for example, the processing temperature is 0 ° C. or higher (ordinary temperature or high temperature). The solution can be prepared by using a dope preparation method and apparatus in a normal solvent cast method.
In the case of a general method, it is preferable to use a halogenated hydrocarbon (particularly, methylene chloride) as the organic solvent. The amount of cellulose acetate is adjusted so as to be contained in the obtained solution in an amount of 10 to 40% by mass. The amount of cellulose acetate is more preferably 10 to 30% by mass.
Arbitrary additives described later may be added to the organic solvent (main solvent). The solution can be prepared by stirring cellulose acetate and an organic solvent at room temperature (for example, 0 to 40 ° C.). The high concentration solution may be stirred under pressure and heating conditions.
Specifically, cellulose acetate and an organic solvent are placed in a pressure vessel and sealed, and stirred while heating to a temperature not lower than the boiling point of the solvent at normal temperature and in a range where the solvent does not boil. Heating temperature is 40 degreeC or more, for example, Preferably it is 60-200 degreeC, More preferably, it is 80-110 degreeC.

  Each component may be coarsely mixed in advance and then placed in a container. Moreover, you may put into a container sequentially. The container needs to be configured so that it can be stirred. The container can be pressurized by injecting an inert gas such as nitrogen gas. Moreover, you may utilize the raise of the vapor pressure of the solvent by heating. Further, after sealing the container, each component may be added under pressure. When heating, it is preferable to heat from the outside of the container. For example, a jacket type heating device can be used. The entire container can also be heated by providing a plate heater outside the container and piping to circulate the liquid. It is preferable to provide a stirring blade inside the container and stir using this. The stirring blade preferably has a length that reaches the vicinity of the wall of the container. A scraping blade is preferably provided at the end of the stirring blade in order to renew the liquid film on the vessel wall. Instruments such as a pressure gauge and a thermometer may be installed in the container. Each component is dissolved in a solvent in the container. The prepared dope is taken out of the container after cooling, or taken out and then cooled using a heat exchanger or the like.

A solution can also be prepared by a cooling dissolution method. In the cooling dissolution method, cellulose acetate can be dissolved in an organic solvent that is difficult to dissolve by a normal dissolution method.
In addition, even if it is a solvent which can melt | dissolve a cellulose acetate with a normal melt | dissolution method, there exists an advantage that a uniform solution can be obtained rapidly according to a cooling melt | dissolution method.
In the cooling dissolution method, first, cellulose acetate is gradually added to an organic solvent with stirring at room temperature. The amount of cellulose acetate is preferably adjusted to be 10 to 40% by mass in the mixture, and more preferably 10 to 30% by mass. Furthermore, you may add the arbitrary additive mentioned later in a mixture.

Next, the mixture is cooled to, for example, -100 to -10 ° C (preferably -80 to -10 ° C, more preferably -50 to -20 ° C, still more preferably -50 to -30 ° C).
The cooling can be performed, for example, in a dry ice / methanol bath (−75 ° C.) or a cooled diethylene glycol solution (−30 to −20 ° C.).
When cooled in this way, the mixture of cellulose acetate and organic solvent solidifies. The cooling rate is preferably 4 ° C./min or more, more preferably 8 ° C./min or more, and further preferably 12 ° C./min or more.
The higher the cooling rate, the better. However, 10,000 ° C / second is the theoretical upper limit, 1,000 ° C / second is the technical upper limit, and 100 ° C / second is the practical upper limit. .
The cooling rate is a value obtained by dividing the difference between the temperature at the start of cooling and the final cooling temperature by the time from the start of cooling to the final cooling temperature.

Furthermore, when the mixture is heated to, for example, 0 to 200 ° C. (preferably 0 to 150 ° C., more preferably 0 to 120 ° C., still more preferably 0 to 50 ° C.), cellulose acetate dissolves in the organic solvent. . The temperature may be increased by simply leaving it at room temperature or in a warm bath. The heating rate is preferably 4 ° C./min or more, more preferably 8 ° C./min or more, and further preferably 12 ° C./min or more.
On the other hand, the heating rate is preferably as high as possible, but 10,000 ° C./sec is a theoretical upper limit, 1,000 ° C./sec is a technical upper limit, and 100 ° C./sec is a practical upper limit. It is.
The heating rate is the value obtained by dividing the difference between the temperature at the start of heating and the final heating temperature by the time from the start of heating until the final heating temperature is reached. is there.
A uniform solution is obtained as described above. If the dissolution is insufficient, the cooling and heating operations may be repeated. Whether the dissolution is sufficient or not can be judged by observing the appearance of the solution by visual observation.

In the cooling dissolution method, it is desirable to use a sealed container in order to avoid moisture mixing due to condensation during cooling. In the cooling and heating operation, when the pressure is applied during cooling and the pressure is reduced during heating, the dissolution time can be shortened.
In order to perform pressurization and decompression, it is desirable to use a pressure-resistant container. In addition, according to differential scanning calorimetry (DSC), a 20 mass% solution obtained by dissolving cellulose acetate (acetylation degree: 60.9%, viscosity average polymerization degree: 299) in methyl acetate by the cooling dissolution method is 33 There exists a quasi-phase transition point between a sol state and a gel state in the vicinity of ° C., and a uniform gel state is obtained below this temperature.
Therefore, this solution needs to be kept at a temperature equal to or higher than the pseudo phase transition temperature, preferably about the gel phase transition temperature plus 10 ° C., for example.
However, this pseudo phase transition temperature varies depending on the degree of acetylation of cellulose acetate, the degree of viscosity average polymerization, the concentration of the solution, and the organic solvent used.

A cellulose acetate film is produced from the prepared cellulose acetate solution (dope) by a solvent cast method.
The dope is cast on a drum or band, and the solvent is evaporated to form a film. The concentration of the dope before casting is preferably adjusted so that the solid content is 18 to 35%. The surface of the drum or band is preferably finished in a mirror state.
Regarding the casting and drying methods in the solvent casting method, for example, US Pat. No. 2,336,310, US Pat. No. 2,367,603, US Pat. No. 2,429,078, US Pat. No. 2,429,297, US Pat. No. 2, U.S. Pat. No. 2,607,704, U.S. Pat. No. 2,73,069, U.S. Pat. No. 2,739,070, British Patent No. 6,407,731, British Patent No. The ones described in JP-A No. 49-5614, JP-A No. 60-176834, JP-A No. 60-203430, and JP-A No. 62-1115035 can be employed.
The dope is preferably cast on a drum or a band having a surface temperature of 10 ° C. or less, and is preferably dried by being exposed to wind for 2 seconds or more after casting.
Further, the obtained film can be peeled off from the drum or band and further dried with high-temperature air whose temperature is successively changed from 100 to 160 ° C. to evaporate the residual solvent.
The above method can be performed, for example, according to the method described in Japanese Patent Publication No. 5-17844. According to this method, it is possible to shorten the time from casting to stripping. In order to carry out this method, it is necessary for the dope to gel at the surface temperature of the drum or band during casting.

  Using the prepared cellulose acylate solution (dope), a film can be formed by casting two or more layers. In this case, it is preferable to produce a cellulose acylate film by a solvent cast method. The dope is cast on a drum or band and the solvent is evaporated to form a film. The dope before casting is preferably adjusted in concentration so that the solid content is 10 to 40%. The surface of the drum or band is preferably finished in a mirror state.

When casting a plurality of cellulose acylate liquids of two or more layers, it is possible to cast a plurality of cellulose acylate solutions, and cellulose is supplied from a plurality of casting openings provided at intervals in the traveling direction of the support. A film may be produced while casting and laminating a solution containing an acylate, for example, in JP-A Nos. 61-158414, 1-122419, and 11-198285. The described method is applicable.
Further, it may be formed into a film by casting a cellulose acylate solution from two casting ports. For example, JP-B-60-27562, JP-A-61-94724, JP-A-61- No. 947245, JP-A 61-104413, JP-A 61-158413, and JP-A 6-134933.
In addition, for example, a cellulose acylate solution in which a flow of a high-viscosity cellulose acylate solution described in JP-A-56-162617 is wrapped with a low-viscosity cellulose acylate solution, and the high-low viscosity cellulose acylate solution is simultaneously extruded. A rate film casting method may be employed.

Also, using two casting ports, the film cast on the support is peeled off by the first casting port, and the second casting is performed on the side that has been in contact with the support surface, so that the film is removed. For example, the method described in Japanese Patent Publication No. 44-20235 is available.
The cellulose acylate solution to be cast may be the same solution or different cellulose acylate solutions, and is not particularly limited. In order to give a function to a plurality of cellulose acylate layers, a cellulose acylate solution corresponding to the function may be extruded from each casting port.
Furthermore, the cellulose acylate solution can be cast simultaneously with other functional layers (for example, an adhesive layer, a dye layer, an antistatic layer, an antihalation layer, a UV absorbing layer, a polarizing layer).

In the conventional single-layer liquid, it is necessary to extrude a cellulose acylate solution having a high concentration and a high viscosity in order to obtain a required film thickness. In many cases, a problem occurred due to the occurrence of an object, a fault, or poor flatness.
As a solution for this, for example, by casting a plurality of cellulose acylate solutions from a casting port, a highly viscous solution can be extruded onto a support at the same time. Not only can the film be produced, but also the use of a concentrated cellulose acylate solution can achieve a reduction in drying load and increase the production speed of the film.

A plasticizer can be added to the cellulose acetate film in order to improve mechanical properties or increase the drying speed.
As the plasticizer, phosphoric acid ester or carboxylic acid ester is used.
Examples of the phosphate ester include triphenyl phosphate (TPP) and tricresyl phosphate (TCP). Representative examples of the carboxylic acid ester include phthalic acid esters and citric acid esters.
Examples of phthalic acid esters include dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), dioctyl phthalate (DOP), diphenyl phthalate (DPP) and diethyl hexyl phthalate (DEHP).
Examples of citrate esters include triethyl O-acetylcitrate (OACTE) and tributyl O-acetylcitrate (OACTB).
Examples of other carboxylic acid esters include butyl oleate, methylacetyl ricinoleate, dibutyl sebacate, and various trimellitic acid esters.
Among these, phthalate ester plasticizers (for example, DMP, DEP, DBP, DOP, DPP, DEHP) are preferable, and DEP and DPP are more preferable.
The amount of the plasticizer added is preferably 0.1 to 25% by mass of the cellulose ester, more preferably 1 to 20% by mass, and further preferably 3 to 15% by mass.

The cellulose acetate film is preferably subjected to a surface treatment.
Examples of the surface treatment include corona discharge treatment, glow discharge treatment, flame treatment, acid treatment, saponification treatment (preferably alkali saponification treatment) and ultraviolet irradiation treatment.
The surface treatment can employ, for example, a method described in JIII Journal of Technical Disclosure (Public Technical No. 2001-1745, pages 30 to 32, published on March 15, 2001, Invention Association).

The alkali saponification treatment is carried out by immersing the cellulose acetate film in a saponification solution or applying the saponification solution to the cellulose acetate film. Among these, the method by application is preferable.
Application methods include dip coating, curtain coating, extrusion coating, bar coating, and E-type application.
The alkali is preferably a hydroxide of an alkali metal (for example, potassium or sodium). That is, the alkali treatment liquid is preferably an alkali metal hydroxide solution. The specified concentration of hydroxide ions in the solution is preferably 0.1 to 3.0N.
The alkali treatment liquid is dissolved in a solvent having good wettability with respect to the film, or a surfactant or a wetting agent (for example, diol or glycerin) is added to the second optical anisotropy of the alkali treatment liquid. The wettability to the layer and the stability of the treatment liquid can be improved.
Examples of the solvent having good wettability with respect to the film include alcohols (for example, isopropyl alcohol, n-butanol, methanol, ethanol).
As the additive for the alkali treatment liquid, for example, the methods described in JP-A-2002-82226 and International Publication WO02 / 46809 can be employed.

An undercoat layer may be provided instead of or in addition to the surface treatment.
The undercoat layer can be provided, for example, by the method described in JP-A-7-333433.
The undercoat layer may be a plurality of layers. For example, a polymer layer containing both a hydrophobic group and a hydrophilic group can be provided as the first undercoat layer, and a hydrophilic polymer layer that adheres well to the alignment film can be provided thereon as the second undercoat layer. In this case, for example, a method described in JP-A-11-248940 can be employed.

<Alignment film>
The optical compensation film of the present invention may have an alignment film used for forming the first optical anisotropic layer. As the alignment film, a polyvinyl alcohol film, a polyimide film, or the like can be used, and a film whose surface is rubbed as desired can be used.
For the rubbing treatment, a rubbing treatment method widely adopted as a liquid crystal alignment treatment process of the liquid crystal display device can be applied. That is, orientation is obtained by rubbing the surface of the film in a certain direction using paper, gauze, felt, rubber, nylon, or polyester fiber. Generally, it is carried out by rubbing several times using a cloth in which fibers having a uniform length and thickness are planted on average.

(Polarizer)
The present invention also relates to a polarizing plate having the optical compensation film of the present invention and a polarizer (polarizing film). In the polarizing plate of the present invention, the optical compensation film can also be used as a protective film for a polarizing film. The second optically anisotropic layer is preferably bonded with the back surface (the surface on which the first optically anisotropic layer is not formed) facing the polarizing film.
Various polarizing films can be used. For example, a polymer film such as a polyvinyl alcohol film dyed with iodine or a dichroic dye can be used.

It is preferable to dispose protective films on both surfaces of the polarizing film, and it is preferable to use the optical compensation film of the present invention as the protective film on one surface. For example, protective film / polarizing film / second optical anisotropic layer / first optical anisotropic layer, or protective film / polarizing film / second optical anisotropic layer / alignment film / first optical difference The laminated body laminated | stacked in order of the anisotropic layer is preferable. The polarizing film and the surface side of the first optical anisotropic layer may be bonded together. An adhesive can be used for bonding, and examples of the adhesive include polyvinyl alcohol resins (including modified polyvinyl alcohols with acetoacetyl groups, sulfonic acid groups, carboxyl groups, and oxyalkylene groups) and boron compound aqueous solutions. It is done. Among these, polyvinyl alcohol resin is preferable.
The thickness of the adhesive layer is preferably 0.01 to 10 μm after drying, and more preferably 0.05 to 5 μm.
A light diffusion film or an antiglare film may be bonded to the surface of the polarizing plate.

When the polarizing film is used in a liquid crystal display device, it is preferable to provide an antireflection layer on the viewing side surface. The antireflection layer may also be used as a protective layer on the viewing side of the polarizing film.
From the viewpoint of suppressing color change due to the viewing angle of the liquid crystal display device, the internal haze of the antireflection layer is preferably 50% or more. As the antireflection layer, for example, those described in JP-A-2001-33783, JP-A-2001-343646, and JP-A-2002-328228 can be employed.

(Liquid crystal display device)
The present invention also relates to a liquid crystal display device having the optical compensation film or the polarizing plate. The optical compensation film and the polarizing plate can be preferably used in a TN mode, OCB mode, VA mode, IPS mode, or other liquid crystal display device, and are particularly suitable for a TN mode or OCB mode liquid crystal display device.

Examples of the present invention will be described below, but the present invention is not limited to the following examples.
(Example 1)
(Production of optical compensation film)
<Production of second optically anisotropic layer (support)>
<< Preparation of cellulose acetate solution >>
The composition shown in the following Table 1 was put into a mixing tank and stirred while heating to 30 ° C. to dissolve each component to prepare cellulose acetate solutions (dope) for inner layer and outer layer.

  The obtained inner layer dope and outer layer dope were cast on a drum cooled to 0 ° C. using a three-layer co-casting die. The film having a residual solvent amount of 70% by mass was peeled off from the drum, both ends were fixed with a pin tenter, and the film was dried at 80 ° C. while transporting at a draw ratio of 110% in the transport direction, resulting in a residual solvent amount of 10%. By the way, it was dried at 110 ° C. Thereafter, it was dried at 140 ° C. for 30 minutes to produce a cellulose acetate film (outer layer: 3 μm, inner layer: 74 μm, outer layer: 3 μm) having a residual solvent of 0.3 mass%. Optical characteristics of the produced cellulose acetate film were measured.

  The width of the obtained cellulose acetate was 1,340 mm, and the thickness was 80 μm. The retardation value (Re) at a wavelength of 550 nm was measured using KOBRA 21ADH, and it was 6 nm. Moreover, it was 90 nm when the retardation value (Rth) in wavelength 550nm was measured.

<Saponification treatment of second optically anisotropic layer>
One side of the prepared second optically anisotropic layer was coated with 25 mL / m ^{2 of} 1.5N potassium hydroxide in isopropyl alcohol, left at 25 ° C. for 5 seconds, and then washed with running water for 10 seconds. The surface of the film was dried by blowing air at 25 ° C. In this way, only one surface of the second optically anisotropic layer was saponified.

<< Formation of alignment film >>
On the saponified surface of the second optically anisotropic layer, an alignment film coating solution having the following composition was applied at 31 mL / m ² with a # 18 wire bar coater. It was dried for 120 seconds with 100 ° C. warm air.
Subsequently, the formed alignment film was rubbed in a direction of 0 ° with respect to the longitudinal direction of the cellulose acetate film.

[Alignment film coating solution composition]
-Modified polyvinyl alcohol shown in the following general formula (B) 10 parts by mass-Water 371 parts by mass-Methanol 119 parts by mass-Glutaraldehyde (crosslinking agent) 0.5 parts by mass

<Formation of first optically anisotropic layer>
To 284 parts by mass of methyl ethyl ketone, 90 parts by mass of the following discotic liquid crystalline compound (D-1), 10 parts by mass of the discotic liquid crystalline compound (D-2), and a fluoroaliphatic group-containing polymer (F- 1) 0.9 parts by mass, 3 parts by mass of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy), and 1 part by mass of a sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) are dissolved in a coating solution ( 1) was prepared.

The coating liquid (1) was rubbed on the roll film transported at 36 m / min by rotating the # 2.5 wire bar at 1,860 revolutions in the same direction as the film transport direction. It applied continuously to the alignment film surface. In the step of continuously heating from room temperature to 100 ° C., the solvent is dried, and then the film surface wind speed corresponding to the discotic liquid crystalline compound layer is 1.5 m / sec in parallel with the film transport direction in the 115 ° C. drying zone. Then, the discotic liquid crystalline compound was aligned by heating for about 90 seconds.
Next, ultraviolet rays with an illuminance of 600 mW were irradiated for 4 seconds with a high-pressure mercury lamp (ultraviolet lamp: output 160 W / cm, emission length 1.6 m), the crosslinking reaction was advanced, and the discotic liquid crystalline compound was fixed in the orientation. Then, it stood to cool to room temperature, wound up in the shape of a cylinder and made it into a roll form, and produced the optical compensation film (1).
The thickness of the first optical anisotropic layer was 830 m. Re (550) was measured at a wavelength of 550 nm using KOBRA 21ADH, and it was 48.2 nm. Further, when retardation was measured at wavelengths of 450 nm and 650 nm, Re (450) / Re (650) was 1.17.

  The surface of the first optical anisotropic layer of the optical compensation film (1) was observed using AFM (SPA400, manufactured by SII), and the surface average surface roughness (Ra) in the range of 10 μm × 10 μm was determined. Further, after the film was placed in an environment of temperature 25 ° C. and humidity 60% RH for one night or longer, the contact angles of water and diiodomethane were measured, and the surface energy was determined using the Owens and Wendt equation. The results are shown in Table 3.

(Preparation of polarizing plate)
A polyvinyl alcohol (PVA) film having a thickness of 80 μm is dyed by immersing it in an aqueous iodine solution having an iodine concentration of 0.05% by mass at 30 ° C. for 60 seconds, and then in an aqueous boric acid solution having a boric acid concentration of 4% by mass. The film was vertically stretched to 5 times the original length while being immersed for 2 seconds, and then dried at 50 ° C. for 4 minutes to obtain a polarizing film having a thickness of 20 μm.
The optical compensation film (1) was immersed in an aqueous sodium hydroxide solution at 55 ° C. at 1.5 mol / L, and then the sodium hydroxide was sufficiently washed away with water. Then, after being immersed in a diluted sulfuric acid aqueous solution at 35 ° C. for 1 minute at 0.005 mol / L, the diluted sulfuric acid aqueous solution was sufficiently washed away by immersion in water. Finally, the sample was thoroughly dried at 120 ° C.
The optical compensation film (1) subjected to the saponification treatment as described above is combined with a commercially available cellulose acetate film subjected to the same saponification treatment, and bonded with a polyvinyl alcohol adhesive so as to sandwich the polarizing film. I got a plate.
Here, Fujitac TF80UL (manufactured by FUJIFILM Corporation) was used as a commercially available cellulose acetate film. At this time, since the polarizing film and the protective films on both sides of the polarizing film are produced in a roll form, the longitudinal directions of the roll films are parallel to each other and are continuously bonded.
Therefore, the longitudinal direction of the optical compensation film roll (the casting direction of the cellulose acetate film) and the polarizer absorption axis were parallel to each other.

(Production of TN liquid crystal display device)
A pair of polarizing plates provided in a liquid crystal display device (AL2216W, manufactured by Nippon Acer Co., Ltd.) using a TN type liquid crystal cell is peeled off, and the optical compensation film (1) is a liquid crystal instead of the above prepared polarizing plate. One sheet was attached to the observer side and the backlight side through an adhesive so as to be on the cell side. At this time, the transmission axis of the polarizing plate on the observer side and the transmission axis of the polarizing plate on the backlight side were arranged so as to be orthogonal to each other.
Using a measuring device (EZ-CONTRAST, manufactured by ELDIM), the front luminance, luminance, and viewing angle dependency of the color and tint of black display (L0) and white display (L7) were measured. The measurement results are shown in Table 2. In addition, the unevenness derived from the surface shape of the first optically anisotropic layer was visually evaluated.

(Example 2)
(Production of optical compensation film)
In Example 1, the fluoroaliphatic group-containing polymer (F-1) of the coating liquid (1) used when forming the first optically anisotropic layer is replaced with the following fluoroaliphatic group-containing polymer (F- An optical compensation film (2) was produced in the same manner as in Example 1 except that 2).

(Production of polarizing plate and liquid crystal display device)
Using this optical compensation film, a polarizing plate was produced in the same manner as in Example 1, and then a TN liquid crystal display device was produced. Further, the surface energy and surface average surface roughness of the optically anisotropic layer were measured in the same manner as in Example 1, and the front contrast, viewing angle dependence, color, surface, etc. of the manufactured liquid crystal display device were measured. The state (presence / absence of unevenness) was measured and evaluated. The results are shown in Table 3.

(Example 3)
(Production of optical compensation film)
In Example 1 above, instead of 1 part by mass of the fluoroaliphatic group-containing polymer (F-1) in the coating liquid (1) used for forming the first optically anisotropic layer, a fluoroaliphatic group-containing polymer An optical compensation film (3) was produced in the same manner as in Example 1 except that 0.45 parts by mass of (F-1) and 0.45 parts by mass of the following fluoroaliphatic group-containing polymer (F-3) were used.

(Production of polarizing plate and liquid crystal display device)
Using this optical compensation film, a polarizing plate was produced in the same manner as in Example 1, and then a TN liquid crystal display device was produced. Further, the surface energy and surface average roughness of the optically anisotropic layer were measured in the same manner as in Example 1, and the front contrast, viewing angle dependency, color, surface shape (unevenness) of the manufactured liquid crystal display device were measured. The presence or absence) was measured and evaluated. The results are shown in Table 3.

(Comparative Example 1)
(Production of optical compensation film)
<Formation of first optically anisotropic layer>
In 215 parts by mass of methyl ethyl ketone, 91 parts by mass of the discotic liquid crystalline compound (D-2), 9 parts by mass of ethylene oxide-modified trimethylolpropane triacrylate (V # 360, manufactured by Osaka Organic Chemical Co., Ltd.), cellulose acetate butyrate 0.75 parts by mass of a rate (CAB551-0.2, manufactured by Eastman Chemical Co.), 0.25 parts by mass of cellulose acetate butyrate (CAB531-1, manufactured by Eastman Chemical Co.), a fluoroaliphatic group-containing polymer shown below (F-H1) 0.5 part by mass, fluoroaliphatic group-containing polymer (F-H2) 0.05 part by mass shown below, photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) 3 parts by mass, sensitization 1 part by weight of the agent (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) is dissolved to prepare a coating solution (H1). .

In the same manner as in Example 3, a second optically anisotropic layer and an alignment film are formed in this order. On the alignment film, the coating liquid (H1) is added to the wire bar # 3.2. The film was rotated at 860 rpm in the same direction as the film conveyance direction, and continuously applied to the alignment film surface of the roll film conveyed at 36 m / min.
Thereafter, in the step of continuously heating from room temperature to 100 ° C., the solvent is dried, and then in the drying zone at 135 ° C., the film surface wind speed corresponding to the discotic liquid crystalline compound layer is 1.5 m parallel to the film conveying direction. / Sec and heated for about 120 seconds to align the discotic liquid crystalline compound.
Next, ultraviolet rays with an illuminance of 600 mW were irradiated for 4 seconds with a high-pressure mercury lamp (ultraviolet lamp: output 160 W / cm, emission length 1.6 m), the crosslinking reaction was advanced, and the discotic liquid crystalline compound was fixed in the orientation. Then, it stood to cool to room temperature, wound up in the shape of a cylinder, and made it into the shape of a roll, and produced the optical compensation film (H1) of comparative example 1.

<< Measurement of optical properties >>
An alignment film is formed on a glass plate by the same method as described above, a first optical anisotropic layer is formed on the alignment film by the same method as described above, and Re (at a wavelength of 550 nm using KOBRA 21ADH. 550) was 50.3 nm. Further, when retardation was measured at wavelengths of 450 nm and 650 nm, Re (450) / Re (650) was 1.27.

(Production of polarizing plate and liquid crystal display device)
Using this optical compensation film, a polarizing plate was produced in the same manner as in Example 1, and then a TN liquid crystal display device was produced. In addition, the surface energy and average surface roughness of the optically anisotropic layer were measured in the same manner as in Example 1, and the front contrast, viewing angle dependency, color, surface condition (presence or absence of unevenness) of the liquid crystal display device ) Was measured and evaluated. The results are shown in Table 3.

(Comparative Example 2)
(Production of optical compensation film)
In Comparative Example 1 described above, instead of the fluoroaliphatic group-containing polymers (F-H1) and (F-H2) in the coating liquid (H1) used for forming the first optically anisotropic layer, the following fluoro An optical compensation film (H2) was produced in the same manner as in Comparative Example 1 except that the aliphatic group-containing polymer (F-H3) was 0.3 parts by mass.

(Production of polarizing plate and liquid crystal display device)
Using this optical compensation film, a polarizing plate was produced in the same manner as in Example 1, and then a TN liquid crystal display device was produced. In addition, the surface energy and average surface roughness of the optically anisotropic layer were measured in the same manner as in Example 1, and the front contrast, viewing angle dependency, color, surface condition (presence or absence of unevenness) of the liquid crystal display device ) Was measured and evaluated. The results are shown in Table 3.

(Examples 4 to 9)
A second optically anisotropic layer (support) was produced in the same manner as in Example 1, and similarly, a saponification treatment and an alignment film were formed on the surface thereof.

<Formation of first optically anisotropic layer>
In 284 parts by mass of methyl ethyl ketone, 90 parts by mass of discotic liquid crystalline compound A shown in Table 4 below, 10 parts by mass of discotic liquid crystalline compound B, and the fluoroaliphatic group-containing polymer (F-1) used in Example 1 ) 0.9 parts by mass, 3 parts by mass of a photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) and 1 part by mass of a sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 4) to (9) were prepared.

(Production of optical compensation film)
A first optical anisotropic layer is formed in the same manner as in Example 1 except that each of the coating liquids (4) to (9) is used in place of the coating liquid (1), and an optical compensation film ( 4) to (9) were prepared.

(Production of polarizing plate and liquid crystal display device)
Using this optical compensation film, a polarizing plate was produced in the same manner as in Example 1, and then a TN liquid crystal display device was produced. Further, the surface energy and surface average surface roughness of the optically anisotropic layer were measured in the same manner as in Example 1, and the front contrast, viewing angle dependence, color, surface, etc. of the manufactured liquid crystal display device were measured. The state (presence / absence of unevenness) was measured and evaluated. The results are shown in Table 5.

  From the results shown in Tables 3 and 5, the liquid crystal display devices (Examples 1 to 9) using the optical compensation films (1) to (9), which are examples of the present invention, all have a high front contrast and are oblique. It can be understood that the color change in the direction was small and no unevenness was observed.

Claims (9)

An optical compensation film comprising an optically anisotropic layer formed by fixing a liquid crystal composition in an aligned state, wherein the surface energy of the optically anisotropic layer is 27 mN / m or less, and the surface average roughness (Ra) is An optical compensation film having a thickness of 1.0 nm or less. The liquid crystal composition contains at least one liquid crystalline compound and at least one polymer including a structural unit represented by the following general formula (A) and a structural unit derived from a fluoroaliphatic group-containing monomer. Item 1. Optical compensation film according to item 1:

In general formula (A), Mp represents a trivalent group constituting a part of the polymer main chain, L represents a single bond or a divalent linking group, and X represents a substituted or unsubstituted aromatic condensed ring function. Represents a group. The optical compensation film according to claim 2, wherein X in the general formula (A) is an unsubstituted or substituted aromatic condensed ring functional group having 5 to 30 carbon atoms. The optical compensation film according to claim 2 or 3, wherein X in the general formula (A) is an unsubstituted or substituted naphthyl group having 10 to 20 carbon atoms. In the general formula (A), the Mp represents the following Mp-1 or Mp-2, and the L represents —O—, —NR ^a11 — (R ^a11 represents a hydrogen atom, a C 1-10 fat. -S-, -C (= O)-, -S (= O) _2- , and a substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, and these The optical compensation film according to any one of claims 2 to 4, which represents a divalent linking group selected from groups formed by linking two or more of:

* Indicates a connection position with L. The optical compensation film according to claim 2, wherein the structural unit derived from the fluoroaliphatic group-containing monomer is a structural unit represented by the following general formula (B):

In general formula (B), Mp ′ represents a trivalent group constituting a part of the polymer main chain, L ′ represents a single bond or a divalent linking group, and Rf contains at least one fluorine atom. Represents a substituent. The optically anisotropic layer according to any one of claims 1 to 6, wherein an in-plane retardation value Re (450 nm) at a wavelength of 450 nm and an in-plane retardation value Re (650 nm) at a wavelength of 650 nm satisfy the following formula: The optical compensation film described.
Re (450 nm) / Re (650 nm) <1.25 The polarizing plate containing a polarizer and the optical compensation film of any one of Claims 1-7. A liquid crystal display device comprising the optical compensation film according to claim 1, or the polarizing plate according to claim 8.