JP5186151B2 - Liquid crystalline composition, optically anisotropic film, optical film, and polarizing plate and liquid crystal display device using the same - Google Patents

Description

  The present invention relates to a liquid crystal composition containing a liquid crystal compound, an optical anisotropic film formed from the liquid crystal composition, an optical film having an optical anisotropic layer formed from the liquid crystal composition, and the optical The present invention relates to a polarizing plate having a film and a liquid crystal display device.

  In recent years, it has been proposed to use an optical compensation sheet having an optically anisotropic layer made of a discotic liquid crystalline compound on a transparent support instead of a stretched birefringent film. This optically anisotropic layer is usually formed by applying a liquid crystal composition containing a liquid crystal compound such as a discotic liquid crystal compound on an alignment film, and heating the liquid crystal compound molecules at a temperature higher than the alignment temperature. It is formed by aligning and fixing the alignment state. In order to produce such an optical compensation sheet, it is required to control liquid crystal molecules to a desired alignment state. As an example of a method for controlling the alignment of a liquid crystal compound, a method using an alignment film (interface treatment) is known. However, it is difficult to uniformly align the liquid crystalline compound from the alignment film interface to the air interface (monodomain alignment) only with the regulating force of the alignment film, and defects such as schlieren are likely to remain. In particular, when the aging time is shortened in order to improve productivity, the occurrence of schlieren defects becomes significant. When a schlieren defect occurs in the optically anisotropic layer, there is a problem that light scattering occurs and optical properties are impaired.

There has also been proposed a method for controlling the alignment of a liquid crystalline compound by using an alignment film (or instead of it) and adding a predetermined additive to the optically anisotropic layer containing the liquid crystalline compound. For example, there is a method in which a compound having a fluorine-substituted alkyl group and a hydrophilic group (a sulfo group is bonded to a benzene ring through a linking group) is added to the optically anisotropic layer to control the tilt angle of the discotic liquid crystalline compound. It has been proposed (see, for example, Patent Document 1). In addition, a method has been proposed in which a hydrophobic excluded volume effect compound is added to the optically anisotropic layer to control the alignment of the liquid crystalline compound (see, for example, Patent Document 2). In addition, a fluoroaliphatic group-containing copolymer has been proposed as an additive that can promote the hybrid alignment of the liquid crystal compound and contribute to an improvement in coating properties (see, for example, Patent Documents 3 and 4). .
JP 2001-330725 A JP 2002-20363 A JP 2004-198511 A JP 2005-164628 A

  By the way, when forming an optically anisotropic layer or the like from a liquid crystal composition, the liquid crystal composition is prepared as a coating liquid, and the coating liquid is dried to bring the molecules of the liquid crystalline compound into a desired alignment state. The present inventor studied the course of drying after the coating solution was applied to the surface. As a result, unevenness occurred during initial drying immediately after coating, and the fluoroaliphatic group-containing copolymer described in Patent Documents 3 and 4 above was used. Even when a polymer is used, it has been found that such unevenness is not sufficiently reduced, and in order to meet the demand for higher brightness and larger screen, it is further necessary to reduce unevenness that occurs during initial drying.

An object of the present invention is to produce an optical film such as an optical compensation film that contributes to high-quality image display without causing unevenness or causing unevenness even when applied to a large-sized liquid crystal display device, and such an optical film. Another object of the present invention is to provide a useful liquid crystalline composition.
Another object of the present invention is to provide a polarizing plate that contributes to high-quality image display without causing unevenness due to the optical film or with little unevenness, and a liquid crystal display capable of displaying such high-quality image. To provide an apparatus.

一般式（１）中、ｉ及びｊはそれぞれ１以上の整数を表し、各繰り返し単位がそれぞれｉ及びｊ種類含まれることを意味し；Ｍはエチレン性不飽和モノマーより誘導され、且つｋ（ｋは１以上の整数）種類含まれる繰り返し単位であり；ａ、ｂ及びｃは重合比を表す質量百分率で、Σａｉは１〜９８質量％の数値を表し、Σｂｊは１〜９８質量％の数値を表し、Σｃｋは１〜９８質量％の数値を表し；Ｒ¹¹及びＲ¹²はそれぞれ、水素原子又はメチル基を表し；Ｘ¹及びＸ²はそれぞれ、酸素原子、イオウ原子又は−Ｎ（Ｒ¹³）−を表し、Ｒ¹³は水素原子又は炭素数１〜４のアルキル基を表し；ｍ１及びｍ２はそれぞれ１〜６の整数を表し、ｎ１は０〜３の整数を表す。 Means for solving the above-mentioned problems are as follows.
[1] A liquid crystal composition containing at least one liquid crystal compound and at least one fluoroaliphatic group-containing polymer represented by the following general formula (1):

In the general formula (1), i and j each represent an integer of 1 or more, meaning that each repeating unit includes i and j types, respectively; M is derived from an ethylenically unsaturated monomer, and k (k Is an integer greater than or equal to 1) types of repeating units; a, b and c are mass percentages representing a polymerization ratio, Σai represents a numerical value of 1 to 98% by mass, and Σbj represents a numerical value of 1 to 98% by mass. Σck represents a numerical value of 1 to 98% by mass; R ¹¹ and R ¹² each represent a hydrogen atom or a methyl group; X ¹ and X ² each represent an oxygen atom, a sulfur atom, or —N (R ¹³ ) -, R ¹³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; m1 and m2 each represent an integer of 1 to 6; and n1 represents an integer of 0 to 3.

[2] The liquid crystalline composition according to [1], wherein Σai / (Σai + Σbj) is 0.2 to 0.8.
[3] The liquid crystalline composition according to [1] or [2], wherein Σai + Σbj is 20 to 50% by mass.
[4] The liquid crystalline composition according to any one of [1] to [3], wherein n1 is 0 in the general formula (1).
[5] A liquid crystalline composition containing at least one liquid crystal compound and at least one fluoroaliphatic group-containing polymer, wherein the fluoroaliphatic group-containing polymer has a viscosity of 200 Pa · s to 10,000 Pa at 25 ° C. -Liquid crystalline composition characterized by being s.
[6] The liquid crystalline composition according to [5], wherein the fluoroaliphatic group-containing polymer is a fluoroaliphatic group-containing polymer represented by the general formula (1) according to claim 1.
[7] The liquid crystalline composition according to any one of [1] to [6], wherein the content of the fluoroaliphatic group-containing polymer is 0.02 to 0.50 mass%.
[8] The surface tension ratio (10 ms / 1000 ms) between 10 ms and 1000 ms measured by the maximum bubble pressure method is 1.00 to 1.20 [1] to [7] Any one of the liquid crystalline compositions.
[9] A product C × F of a concentration C% by mass of the fluoroaliphatic group-containing polymer and a fluorine content F% in the fluoroaliphatic group-containing polymer is 0.05 to 0.12. The liquid crystalline composition according to any one of [1] to [8].
[10] The liquid crystal composition according to any one of [1] to [9], wherein the liquid crystal compound is a discotic compound.
[11] An optically anisotropic film formed from the composition according to any one of [1] to [10].
[12] When the fluorine atom abundance ratio (ESCA: F / C) at the air interface is 100, the fluorine atom abundance ratio (ESCA: F / C) at a position of 10 nm from the air interface is 2-10. [11] The optically anisotropic film according to [11].
[13] An optical film having an optically anisotropic layer formed from the liquid crystalline composition according to any one of [1] to [10].
[14] A polarizing plate comprising the optical film of [13] and a polarizer.
[15] A liquid crystal display device comprising the optical film of [13] and / or the polarizing plate of [13].

ADVANTAGE OF THE INVENTION According to this invention, even when it applies to a large sized liquid crystal display device, it is useful for preparation of the optical film which contributes to displaying an image with high display quality, without producing nonuniformity or few nonuniformity, and such an optical film Liquid crystalline composition can be provided.
In addition, according to the present invention, there is provided a polarizing plate that contributes to high-quality image display without causing non-uniformity due to the optical film or less, and a liquid crystal display device capable of displaying such high-quality image. Can be provided.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail. In the present specification, “to” is used to mean that the numerical values described before and after it are included as a lower limit value and an upper limit value.
[Liquid crystal composition]
The liquid crystalline composition of the present invention contains at least one liquid crystalline compound and at least one predetermined fluoroaliphatic group-containing polymer.
-Fluoroaliphatic group containing polymer The fluoroaliphatic group containing polymer used for this invention is represented by following General formula (1).

In the general formula (1), i and j each represent an integer of 1 or more, meaning that each repeating unit includes i and j types, respectively; M is derived from an ethylenically unsaturated monomer, and k (k Is an integer greater than or equal to 1) types of repeating units; a, b and c are mass percentages representing a polymerization ratio, Σai represents a numerical value of 1 to 98% by mass, and Σbj represents a numerical value of 1 to 98% by mass. Σck represents a numerical value of 1 to 98% by mass; R ¹¹ and R ¹² each represent a hydrogen atom or a methyl group; X ¹ and X ² each represent an oxygen atom, a sulfur atom, or —N (R ¹³ ) - it represents, R ¹³ represents an alkyl group having 1 to 4 carbon hydrogen atom or a carbon; m1 and m2 represents an integer of 1 to 6; n1 represents an integer of 0 to 3.

In the above formula (1), the following repeating units A and B are respectively a fluoroaliphatic group-containing monomer A having a terminal of-(CF ₂ CF ₂ ) ₃ F and a terminal of-(CF ₂ CF ₂ ) ₂ F. It is a repeating unit derived from the fluoroaliphatic group-containing monomer B.

In the repeating units A and B, X ¹ and X ² are each preferably O. That is, the repeating units A and B are each preferably a repeating unit derived from a (meth) acrylic monomer.
m1 and m2 are each preferably 1 to 4, and more preferably 1 to 2.
n1 is preferably 0 to 2, more preferably 0 or 1, and most preferably 0.

  Examples of the fluoroaliphatic group-containing monomer for deriving the repeating unit A are listed below, but are not limited thereto. Especially, exemplary compound A1-1-6 and A2-1-6 which are (meth) acrylic-type monomers are preferable. In addition, although the following exemplary compounds enumerate the compound of n1 = 0 in Formula (1), the compound whose n1 is 1-3, of course, the fluoro aliphatic group containing monomer which derives the said repeating unit A Is included in the example.

  Examples of the fluoroaliphatic group-containing monomer for deriving the repeating unit B are listed below, but are not limited thereto. Especially, exemplary compound B1-1-6 and B2-1-6 which are (meth) acrylic-type monomers are preferable.

  The fluoroaliphatic group-containing monomer can be produced by a telomerization method (also referred to as a telomer method) or an oligomerization method (also referred to as an oligomer method). Regarding the production method of these fluoroaliphatic compounds, for example, “Synthesis and function of fluorine compounds” (supervision: Nobuo Ishikawa, published by CMC Co., 1987), “Chemistry of Organic Fluorine Compounds” II "(Monograph 187, Ed by Milos Hudlicky and Attila E. Pavlath, American Chemical Society 1995), pages 747-752. The telomerization method is a method of synthesizing a telomer by radical polymerization of a fluorine-containing vinyl compound such as tetrafluoroethylene using an alkyl halide having a large chain transfer constant such as iodide as a telogen (example in Scheme-1). showed that).

  The obtained terminal iodinated telomer is usually subjected to appropriate terminal chemical modification such as [Scheme2], and led to a fluoroaliphatic compound.

In the formula (1), M is a repeating unit derived from an ethylenically unsaturated monomer. M is not particularly limited, but is preferably a repeating unit having a polar group having hydrogen bonding in the side chain. M is preferably a repeating unit represented by the following general formula (2).

In the general formula (2), R ¹ , R ² , and R ³ each independently represent a hydrogen atom, an alkyl group, a halogen atom, or a group represented by -LQ. L represents a divalent linking group, and Q represents a polar group having hydrogen bonding properties.

L is preferably an arbitrary group selected from the following linking group group, or a divalent linking group formed by combining two or more thereof.
(Linked group group)
Single bond, —O—, —CO—, —NR ₄ —, —S—, —SO ₂ —, —P (═O) (OR ₅ ) —, alkylene group, arylene group (R ⁴ is a hydrogen atom, alkyl A group, an aryl group, or an aralkyl group, and R ⁵ represents an alkyl group, an aryl group, or an aralkyl group.)

More specifically, in general formula (2), R ¹ , R ² and R ³ are each independently a hydrogen atom, an alkyl group, a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.) ) Or a group represented by -LQ described later, preferably a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a chlorine atom, or a group represented by -LQ, more preferably hydrogen. An atom and an alkyl group having 1 to 4 carbon atoms are preferable, and a hydrogen atom and an alkyl group having 1 to 2 carbon atoms are particularly preferable. Specific examples of the alkyl group that R ¹ , R ^2, and R ³ can take include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, a sec-butyl group, and the like. The alkyl group may have one or more substituents. Examples of the substituent include a halogen atom, aryl group, heterocyclic group, alkoxyl group, aryloxy group, alkylthio group, arylthio group, acyl group, hydroxyl group, acyloxy group, amino group, alkoxycarbonyl group, acylamino group, oxycarbonyl Group, carbamoyl group, sulfonyl group, sulfamoyl group, sulfonamido group, sulfolyl group, carboxyl group and the like.

  The carbon number of the alkyl group does not include the carbon atom of the substituent. The same applies to the carbon number of other groups.

L is a single bond, —O—, —CO—, —NR ⁴ —, —S—, —SO ₂ —, —PO (OR ⁵ ) —, an alkylene group, an arylene group, or a combination thereof. Represents a valent linking group. Here, R ⁴ represents a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group. R ⁵ represents an alkyl group, an aryl group, or an aralkyl group.
L preferably includes a single bond, —O—, —CO—, —NR ⁴ —, —S—, —SO ₂ —, an alkylene group, or an arylene group, and includes —CO—, —O—, and —NR. ⁴ - it is particularly preferred that contain an alkylene group or an arylene group. Further, it preferably contains an alkyleneoxy group containing both —O— and an alkylene group, and preferably contains a polyalkyleneoxy group containing a repeating alkyleneoxy group.
When L contains an alkylene group, the alkylene group preferably has 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, and particularly preferably 1 to 6 carbon atoms. Specific examples of particularly preferable alkylene groups include a methylene group, an ethylene group, a trimethylene group, a tetrabutylene group, and a hexamethylene group. Moreover, the alkylene group (meaning also including the alkylene group contained in an alkyleneoxy group) may have a branched structure, and it is preferable that carbon number of the alkylene chain of a branched part is 1-3.

When L contains an arylene group, the carbon number of the arylene group is preferably 6 to 24, more preferably 6 to 18, and particularly preferably 6 to 12. Specific examples of particularly preferred arylene groups include phenylene groups and naphthalene groups.
When L contains a divalent linking group (that is, an aralkylene group) obtained by combining an alkylene group and an arylene group, the carbon number of the aralkylene group is preferably 7 to 34, more preferably 7 to 26, and particularly preferably. 7-16. Specific examples of particularly preferred aralkylene groups include a phenylenemethylene group, a phenyleneethylene group, and a methylenephenylene group.
The group listed as L may have an appropriate substituent. Examples of such a substituent include those similar to the substituents exemplified above as the substituents for R ^{1 to} R ³ .
Although the specific structure of L is illustrated below, this invention is not limited to these specific examples.

However, in L-28, R ^{51 to} R ⁵⁸ are each a hydrogen atom or an alkyl group (preferably having 1 to 4 carbon atoms, more preferably 1 to 2 carbon atoms), and n is 1 to 12 (preferably 2). An integer of 10 to 10. One of R ⁵³ and R ⁵⁴ , R ⁵⁵ and R ⁵⁶ , and R ⁵⁷ and R ⁵⁸ is preferably a hydrogen atom and the other is an alkyl group.

Q is not particularly limited as long as it is a polar group having hydrogen bonding properties. Preferably, hydroxyl group, carboxyl group, salt of carboxyl group (for example, lithium salt, sodium salt, potassium salt, ammonium salt (for example, ammonium, tetramethylammonium, trimethyl-2-hydroxyethylammonium, tetrabutylammonium, trimethylbenzylammonium, dimethylphenyl) Ammonium, etc.), pyridinium salts, etc.), amides of carboxylic acids (N unsubstituted or N-mono lower alkyl substituted, such as —CONH ₂ , —CONHCH ₃ etc.) sulfo groups, sulfo group salts (cations forming salts) examples of are the same as those described in the above carboxyl group), a sulfonamido group (N unsubstituted, or N- mono-lower-alkyl substituents, -SO ₂ NH _2, such as -SO ₂ NHCH _3), phospho group, phospho group Salt of the cation forming the salt Examples are the same as those described in the above carboxyl group), phosphonamides (N unsubstituted, or N- mono-lower-alkyl substituents, for example, _{-OP (= O) (NH 2} ) 2, -OP (= O) (NHCH ₃ ) ₂ ), a ureido group (—NHCONH ₂ ), an amino group (—NH ₂ , —NHCH ₃ ) which is unsubstituted or monosubstituted at the N-position (wherein the lower alkyl group is a methyl group or an ethyl group) Represents).
A hydroxyl group, a carboxyl group, a sulfo group and a phospho group are more preferred, a hydroxyl group or a carboxyl group is more preferred, and a hydroxyl group is particularly preferred.

The repeating unit represented by the general formula (2) is preferably a repeating unit derived from a (meth) acrylic monomer.
Specific examples of the ethylenically unsaturated monomer for deriving the repeating unit M are shown below, but are not limited thereto.

The fluoroaliphatic group polymer represented by the general formula (1) includes at least one repeating unit A, B and M, respectively. That is, in the above formula (1), i, j and k, which mean the number of types of each repeating unit, are each an integer of 1 or more. The fluoroaliphatic group polymer represented by the general formula (1) may contain two or more kinds of each repeating unit, and may contain repeating units other than the repeating units A, B and M. .
For example, the fluoroaliphatic group-containing polymer may contain one type of repeating unit derived from a monomer selected from the following monomer group, or may contain two or more types.
Monomer group (1) Alkenes Ethylene, propylene, 1-butene, isobutene, 1-hexene, 1-dodecene, 1-octadecene, 1-eicocene, hexafluoropropene, vinylidene fluoride, chlorotrifluoroethylene, 3, 3, 3-trifluoropropylene, tetrafluoroethylene, vinyl chloride, vinylidene chloride, etc .;
(2) Dienes 1,3-butadiene, isoprene, 1,3-pentadiene, 2-ethyl-1,3-butadiene, 2-n-propyl-1,3-butadiene, 2,3-dimethyl-1,3 -Butadiene, 2-methyl-1,3-pentadiene, 1-phenyl-1,3-butadiene, 1-α-naphthyl-1,3-butadiene, 1-β-naphthyl-1,3-butadiene, 2-chloro -1,3-butadiene, 1-bromo-1,3-butadiene, 1-chlorobutadiene, 2-fluoro-1,3-butadiene, 2,3-dichloro-1,3-butadiene, 1,1,2- Trichloro-1,3-butadiene and 2-cyano-1,3-butadiene, 1,4-divinylcyclohexane and the like;

(3) Derivatives of α, β-unsaturated carboxylic acid (3a) Alkyl acrylates Methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate , Amyl acrylate, n-hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, tert-octyl acrylate, dodecyl acrylate, phenyl acrylate, benzyl acrylate, 2-chloroethyl acrylate, 2-bromoethyl acrylate, 4-chlorobutyl acrylate, 2-cyanoethyl acrylate, 2-acetoxyethyl acrylate, methoxybenzyl Chryrate, 2-chlorocyclohexyl acrylate, furfuryl acrylate, tetrahydrofurfuryl acrylate, 2-methoxyethyl acrylate, ω-methoxypolyethylene glycol acrylate (number of added polyoxyethylene: n = 2 to 100), 3-methoxy Butyl acrylate, 2-ethoxyethyl acrylate, 2-butoxyethyl acrylate, 2- (2-butoxyethoxy) ethyl acrylate, 1-bromo-2-methoxyethyl acrylate, 1,1-dichloro-2-ethoxyethyl acrylate, glycidyl acrylate Such);
(3b) Alkyl methacrylates Methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, amyl methacrylate, n-hexyl methacrylate, cyclohexyl methacrylate, 2 -Ethylhexyl methacrylate, n-octyl methacrylate, stearyl methacrylate, benzyl methacrylate, phenyl methacrylate, allyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, cresyl methacrylate, naphthyl methacrylate, 2-methoxyethyl methacrylate, 3-methoxybutyl methacrylate, ω Methoxypolyethylene glycol methacrylate (number of added polyoxyethylene: n = 2 to 100), 2-acetoxyethyl methacrylate, 2-ethoxyethyl methacrylate, 2-butoxyethyl methacrylate, 2- (2-butoxyethoxy) ethyl methacrylate Glycidyl methacrylate, 3-trimethoxysilylpropyl methacrylate, allyl methacrylate, 2-isocyanatoethyl methacrylate, etc .;
(3c) Diesters of unsaturated polycarboxylic acids Dimethyl maleate, dibutyl maleate, dimethyl itaconate, dibutyl taconate, dibutyl crotonate, dihexyl crotonate, diethyl fumarate, dimethyl fumarate, etc .;
(3d) Amides of α, β-unsaturated carboxylic acids N, N-dimethylacrylamide, N, N-diethylacrylamide, Nn-propylacrylamide, N-tertbutylacrylamide, N-tertoctylmethacrylamide, N- Cyclohexylacrylamide, N-phenylacrylamide, N- (2-acetoacetoxyethyl) acrylamide, N-benzylacrylamide, N-acryloylmorpholine, diacetone acrylamide, N-methylmaleimide and the like;

(4) Unsaturated nitriles Acrylonitrile, methacrylonitrile, etc .;
(5) Styrene and its derivatives Styrene, vinyl toluene, ethyl styrene, p-tert butyl styrene, methyl p-vinyl benzoate, α-methyl styrene, p-chloromethyl styrene, vinyl naphthalene, p-methoxy styrene, p-hydroxy Methyl styrene, p-acetoxy styrene, etc .;
(6) Vinyl esters Vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl benzoate, vinyl salicylate, vinyl chloroacetate, vinyl methoxyacetate, vinyl vinyl acetate, etc .;
(7) Vinyl ethers Methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, n-pentyl vinyl ether, n-hexyl vinyl ether, n-octyl vinyl ether, n-dodecyl Vinyl ether, n-eicosyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, fluorobutyl vinyl ether, fluorobutoxyethyl vinyl ether, etc .; and (8) other polymerizable monomers N-vinyl pyrrolidone, methyl vinyl ketone, phenyl vinyl ketone, Methoxyethyl vinyl ketone, 2-vinyl oxazoline, 2-isopropenyl oxazoline .

In the general formula (1), a, b and c are mass percentages representing the polymerization ratio of the monomer for deriving each repeating unit, Σai represents a numerical value of 1 to 98% by mass, and Σbj represents 1 to 98% by mass. Σck represents a numerical value of 1 to 98% by mass. Σai is 5 to 40% by mass, Σbj is 5 to 40% by mass, Σck is preferably 20 to 90% by mass, Σai is 10 to 35% by mass, and Σbj is 10 to 35% by mass. And Σck is more preferably 30 to 80% by mass. The fluoroaliphatic group-containing polymer represented by the general formula (1) may contain a repeating unit other than the repeating units A, B and M, that is, Σai + Σbj + Σck <100% by mass. The repeating units other than the repeating units A, B and M are preferably not included, that is, Σai + Σbj + Σck = 100% by mass.

In addition, it is preferable that the ratio of the repeating units A and B derived from the fluoroaliphatic group-containing monomer contained in the fluoroaliphatic group-containing polymer is within a predetermined range, since unevenness in the initial stage of drying can be further reduced. Specifically, the sum (Σai + Σbj) of the total mass Σai of the i-type repeating unit A and the total mass of the j-type repeating unit B (Σai + Σbj) is preferably 20 to 50% by mass, and 25 to 45% by mass. More preferably, it is more preferably 25 to 40% by mass. When (Σai + Σbj) is less than 20% by mass, the control of the liquid crystal compound at the air interface is not sufficient, and the effect of the present invention to reduce the unevenness of the optical film may be weak, and when it exceeds 50% by mass, When the liquid crystalline composition is applied to the surface (for example, the surface of a transparent support such as a polymer film), the applicability is not sufficient and repelling failure may occur. When (Σai + Σbj) is in the above range, there is no such problem, and unevenness during initial drying can be further reduced.
From the same viewpoint, the ratio of Σai to Σai + Σbj (Σai / (Σai + Σbj)) is preferably 0.2 to 0.8, more preferably 0.3 to 0.6, More preferably, it is 35-0.55. When the ratio (Σai / (Σai + Σbj)) is less than 0.2, the liquid crystal compound is not sufficiently controlled at the air interface, and the effect of the present invention for reducing unevenness of the optical film may be weak. If it exceeds .8, the coating property when the liquid crystalline composition is applied to the surface (for example, the surface of a transparent support such as a polymer film) is not sufficient, and repelling failure may occur. It is preferable that Σai / (Σai + Σbj)) be in the above range because there is no such problem and unevenness during initial drying can be further reduced.

  Specific examples of fluoroaliphatic group-containing polymers that can be used in the present invention are summarized in the following table, but are not limited to the following specific examples. In the table below, repeating units A, B, and M are monomeric compound Nos. Derived from the respective repeating units. It is specified by.

  The liquid crystalline composition of the present invention may contain at least one kind of the above-described fluoroaliphatic group-containing polymer, and of course may contain two or more kinds. In the composition, the addition amount of the fluoroaliphatic group-containing polymer is preferably 0.01 to 20% by mass, preferably 0.05 to 10% by mass, based on the mass of the liquid crystal compound (preferably discotic liquid crystal compound). Is more preferable, and 0.1-5 mass% is further more preferable.

  In addition, the preferred range of the concentration C mass% of the fluoroaliphatic group-containing polymer in the composition (in the case where the composition is prepared as a coating solution or the like, solid content) is within the fluoroaliphatic group-containing polymer. It varies depending on the fluorine content F%. In order to further reduce unevenness in the initial stage of drying, the product of the concentration C% by mass of the fluoroaliphatic group-containing polymer and the fluorine content F% in the fluoroaliphatic group-containing polymer is 0.05 to 0.12. It is preferable that it is 0.06-0.09, and it is further more preferable that it is 0.06-0.08. When C × F is less than 0.05, the liquid crystal compound is not sufficiently controlled at the air interface, and the appearance characteristics (the degree of unevenness) of the optical film may be deteriorated. When the composition is applied to the surface (for example, the surface of a transparent support such as a polymer film), the coating properties may not be sufficient, and the appearance characteristics of the optical film (repel failure may occur) may deteriorate. When C × F is within the above range, there is no such problem, and unevenness during initial drying can be further reduced.

Second fluoroaliphatic group-containing polymer The liquid crystalline composition of the present invention contains a fluorofatty outside the scope of the fluoroaliphatic group-containing polymer (hereinafter referred to as “first fluoroaliphatic group-containing polymer”). One or more group group-containing polymers (hereinafter sometimes referred to as “second fluoroaliphatic group-containing polymer”) may be added. The second fluoroaliphatic group-containing polymer includes at least one repeating unit derived from a monomer having a fluoroaliphatic group, a carboxyl group (—COOH) or a salt thereof, a sulfo group (—SO ₃ H) or the It preferably contains a salt, or at least one repeating unit derived from a monomer having an acidic group such as phosphonoxy {—OP (═O) (OH) ₂ } or a salt thereof.

  Preferred examples of the second fluoroaliphatic group-containing polymer include the following polymer A (represented by a repeating unit derived from a fluoroaliphatic group-containing monomer and the following general formula (1a) described in WO2006 / 001504. And a copolymer containing a repeating unit).

（式中、Ｒ^1a、Ｒ^2aおよびＲ^3aはそれぞれ、水素原子または置換基を表し；Ｌ^aは下記の連結基群から選ばれる２価の連結基または下記の連結基群から選ばれる２つ以上を組み合わせて形成される２価の連結基を表し、
（連結基群）
単結合、−Ｏ−、−ＣＯ−、−ＮＲ^4a−（Ｒ^4aは水素原子、アルキル基、アリール基、またはアラルキル基を表す）、−Ｓ−、−ＳＯ₂−、−Ｐ（＝Ｏ）（ＯＲ^5a）−（Ｒ^5aはアルキル基、アリール基、またはアラルキル基を表す）、アルキレン基およびアリーレン基；
Ｑ^aはカルボキシル基（−ＣＯＯＨ）もしくはその塩、スルホ基（−ＳＯ₃Ｈ）もしくはその塩、またはホスホノキシ｛−ＯＰ（＝Ｏ）（ＯＨ）₂｝もしくはその塩を表す。）

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

^{Wherein, R 1a, R 2a, R} 3a, and L ^a are each, in the general formula (2), respectively as the preferred ranges of R ^1, R ^2, R ³ and L synonymous.

  The repeating unit derived from the fluoroaliphatic group-containing monomer of the second fluoroaliphatic group-containing polymer may be any one of the repeating units A and B. A repeating unit derived from a fluoroaliphatic group-containing monomer represented by the following formula (3) is also preferable.

一般式（３）中、Ｒ⁵は水素原子またはメチル基を表し、Ｘ⁵は酸素原子、イオウ原子または−Ｎ（Ｒ¹⁵）−を表し、Ｒ¹⁵は水素原子または炭素数１〜４のアルキル基を表す。Ｚは水素原子又はフッ素原子を表し、ｍ⁵は１〜６の整数を表し、ｎ⁵は２〜４の整数を表す。

In general formula (3), R ⁵ represents a hydrogen atom or a methyl group, X ⁵ represents an oxygen atom, a sulfur atom or —N (R ¹⁵ ) —, and R ¹⁵ represents a hydrogen atom or an alkyl having 1 to 4 carbon atoms. Represents a group. Z represents a hydrogen atom or a fluorine atom, m ⁵ represents an integer of 1 to 6, and n ⁵ represents an integer of 2 to 4.

  The second fluoroaliphatic group-containing polymer may contain a repeating unit having a hydrogen bonding group represented by the general formula (2), or the monomer groups (1) to (7). It may contain a repeating unit derived from at least one monomer selected from: Hereinafter, exemplary compounds of polymers that can be used as the second fluoroaliphatic-containing polymer in the liquid crystalline composition of the present invention will be listed, but the present invention is not limited to the following specific examples.

  In the embodiment in which the second fluoroaliphatic group-containing polymer is added, the addition amount (% by mass) of the second fluoroaliphatic group-containing polymer is the addition amount (% by mass) of the first fluoroaliphatic group-containing polymer. It is preferable that:

The weight average molecular weight of the first fluoroaliphatic group-containing polymer (and optionally added second fluoroaliphatic group-containing polymer) is preferably 1,000,000 or less. More preferred is a weight average molecular weight of 500,000 or less, and particularly preferred is a weight average molecular weight of 100,000 or less.
The weight average molecular weight can be measured as a value in terms of polyethylene oxide (PEO) using gel permeation chromatography (GPC).

  There are no particular restrictions on the method for producing the first fluoroaliphatic group-containing polymer (and the second fluoroaliphatic group-containing polymer that is optionally added). For example, it can be produced by a polymerization method such as cationic polymerization using a vinyl group, radical polymerization, or anionic polymerization, and among these, the radical polymerization method is particularly preferred because it can be used for general purposes.

  As the polymerization initiator for radical polymerization, known compounds such as radical thermal polymerization initiators and radical photopolymerization initiators can be used, and it is particularly preferable to use radical thermal polymerization initiators. Here, the radical thermal polymerization initiator is a compound that generates radicals by heating to a decomposition temperature or higher. Examples of such radical thermal polymerization initiators include diacyl peroxide (acetyl peroxide, benzoyl peroxide, etc.), ketone peroxide (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), hydroperoxide (hydrogen peroxide, tert. -Butyl hydroxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyesters (tert-butyl peroxyacetate, tert) -Butyl peroxypivalate, etc.), azo compounds (azobisisobutyronitrile, azobisisovaleronitrile, etc.), persulfates (ammonium persulfate, sodium persulfate) And potassium persulfate) and the like. Such radical thermal polymerization initiators can be used singly or in combination of two or more.

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

  An organic solvent is used for solution polymerization. These organic solvents can be arbitrarily selected as long as the objects and effects of the present invention are not impaired. These organic solvents are usually organic compounds having boiling points under atmospheric pressure in the range of 50 to 200 ° C., and organic compounds that uniformly dissolve each component are preferred. Examples of preferable organic solvents include alcohols such as isopropanol and butanol, ethers such as dibutyl ether, ethylene glycol dimethyl ether, tetrahydrofuran and dioxane, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, ethyl acetate and acetic acid. Examples thereof include esters such as butyl, amyl acetate and γ-butyrolactone, and aromatic hydrocarbons such as benzene, toluene and xylene. These organic solvents can be used alone or in combination of two or more. Furthermore, a water-mixed organic solvent in which water is used in combination with the above organic solvent is also applicable from the viewpoint of the solubility of the monomer and the polymer to be produced.

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

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

-Liquid crystalline composition Next, the liquid crystalline compound used for the liquid crystalline composition of this invention is demonstrated. Examples of liquid crystal compounds that can be used in the present invention include rod-like liquid crystal compounds and discotic liquid crystal compounds. The rod-like liquid crystal compound and the discotic liquid crystal compound may be a high-molecular liquid crystal or a low-molecular liquid crystal, and further include those in which the low-molecular liquid crystal is cross-linked and no longer exhibits liquid crystallinity.

(Bar-shaped liquid crystalline compound)
Examples of rod-like liquid crystalline compounds include azomethines, azoxys, cyanobiphenyls, cyanophenyl esters, benzoic acid esters, cyclohexanecarboxylic acid phenyl esters, cyanophenylcyclohexanes, cyano-substituted phenylpyrimidines, alkoxy-substituted phenylpyrimidines. , Phenyldioxanes, tolanes and alkenylcyclohexylbenzonitriles are preferably used.

The rod-like liquid crystalline compound includes a metal complex. In addition, a liquid crystal polymer containing a rod-like liquid crystalline molecule in a repeating unit can also be used as the rod-like liquid crystalline molecule. In other words, the rod-like liquid crystal molecule may be bonded to a (liquid crystal) polymer.
For rod-like liquid crystalline compounds, see Chapter 4, Chapter 7 and Chapter 11 of the Chemistry of the Quarterly Chemical Review Vol. 22 Liquid Crystal Chemistry (1994) edited by the Chemical Society of Japan, and the 142nd Committee of the Japan Society for the Promotion of Science. Described in Chapter 3.

  The birefringence of the rod-like liquid crystalline compound is preferably in the range of 0.001 to 0.7.

  The rod-like liquid crystalline compound preferably has a polymerizable group in order to fix its alignment state. The polymerizable group is preferably an unsaturated polymerizable group or an epoxy group, more preferably an unsaturated polymerizable group, and most preferably an ethylenically unsaturated polymerizable group.

(Discotic liquid crystalline compounds)
Examples of discotic liquid crystalline compounds include C.I. Benzene derivatives described in a research report of Destrade et al. (Mol. Cryst. 71, 111 (1981)), C.I. Destrode et al. (Mol. Cryst. 122, 141 (1985), Physics lett, A, 78, 82 (1990)) described in The cyclohexane derivatives described in the research report of Kohne et al. (Angew. Chem. 96, 70 (1984)) and M.M. Lehn et al. (J. Chem. Commun., 1794 (1985)), J. Chem. Azacrown-type and phenylacetylene-type macrocycles described in the research report of Zhang et al. (J. Am. Chem. Soc. 116, 2655 (1994)) are included.

  As a discotic liquid crystalline compound, a compound having liquid crystallinity in which a linear alkyl group, an alkoxy group, and a substituted benzoyloxy group are radially substituted as a side chain of the mother nucleus with respect to the mother nucleus at the center of the molecule Is also included. The molecule or the assembly of molecules is preferably a compound having rotational symmetry and imparting a certain orientation. In the optically anisotropic layer formed from discotic liquid crystalline molecules, the compound finally contained in the optically anisotropic layer does not need to be a discotic liquid crystalline molecule. Also included are compounds having a group that reacts with heat or light and, as a result, polymerized or cross-linked by reaction with heat or light, resulting in a high molecular weight and loss of liquid crystallinity. Preferred examples of the discotic liquid crystalline compound are described in JP-A-8-50206. The polymerization of discotic liquid crystalline compounds 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 formula (5).
General formula (5)
D (-L ¹ Q ¹ ) _n
In formula (5), D is a discotic core; L ¹ is a divalent linking group, Q ¹ is a polymerizable group, and n is an integer of 4-12.

An example of the disk-shaped core (D) is shown below. In each of the following examples, LQ (or QL) means a combination of a divalent linking group (L ¹ ) and a polymerizable group (Q ¹ ).

Other additives Examples of the additive used together with the discotic liquid crystalline compound include a plasticizer, a surfactant, a polymerizable monomer and a polymer. The degree of change in the orientation direction of the long axis can be adjusted by selecting the liquid crystalline molecule and the additive as described above.
The plasticizer, surfactant and polymerizable monomer used together with the discotic liquid crystalline compound are compatible with the discotic liquid crystalline compound, and can change the tilt angle of the discotic liquid crystalline compound or change the orientation. It is preferable not to inhibit. Among the additive components, addition of a polymerizable monomer (eg, a compound having a vinyl group, a vinyloxy group, an acryloyl group and a methacryloyl group) is preferable. The amount of the compound added is generally in the range of 1 to 50% by weight and preferably in the range of 5 to 30% by weight with respect to the discotic liquid crystalline compound. In addition, when a monomer having 4 or more polymerizable reactive functional groups is mixed and used, the adhesion between the alignment film and the optically anisotropic layer can be improved.

It is preferable to add a cellulose ester as the additive because it can suppress the occurrence of repelling when the composition is applied. Suitable cellulose esters include cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, hydroxypropylcellulose, methylcellulose and carboxymethylcellulose. Among them, cellulose acetate butyrate is preferable, and cellulose acetate butyrate having a degree of butyrylation of 40% or more is more preferable.
The amount of addition is preferably 0.01 to 20%, more preferably 0.05 to 10%, and particularly preferably 0.05 to 5% by weight percentage with respect to the total amount of the liquid crystal compound.

Organic solvent The liquid crystalline composition of the present invention may be prepared as a coating solution. As a solvent used for preparing the coating solution, an organic solvent is preferably used. 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.

When producing a highly uniform optically anisotropic film or optical film, the surface tension of the coating solution is preferably 25 mN / m or less, and more preferably 22 mN / m or less.
Further, in order to further reduce the unevenness at the time of initial drying, the surface tension ratio (10 ms / 1000 ms) between 10 ms and 1000 ms measured by the maximum bubble pressure method of the liquid crystal composition coating solution, It is preferably 1.00 to 1.20, more preferably 1.00 to 1.15, and even more preferably 1.00 to 1.10. When the surface tension ratio exceeds 1.20, the moving speed to the air interface immediately after coating is slow, the stability of the coating film surface at the air interface is inferior, and the effect of reducing unevenness during initial drying may not be sufficient. is there. When the surface tension ratio is within the above range, there is no such problem, and unevenness during initial drying can be further reduced.
The measurement of surface tension by the maximum bubble pressure method is described in detail in “Chemical Handbook 5th edition”, Chapter 8, Interfaces and Colloids, page 90, 8.2 Surface tension and wetting, “ASTM D3825-90”, etc. Therefore, the surface tension of the liquid crystalline composition of the present invention can also be measured with reference to the method described in the publication. Further, in order to continuously measure the surface tension with time, a surface tension meter such as “MPT2” manufactured by LAUDA can be used.

  The present invention also provides a liquid crystalline composition containing at least one liquid crystal compound and at least one fluoroaliphatic group-containing polymer, wherein the fluoroaliphatic group-containing polymer has a viscosity of 200 Pa · at 25 ° C. The present invention also relates to a liquid crystalline composition characterized by being s to 10000 Pa · s. When the fluoroaliphatic group-containing polymer has a viscosity at 25 ° C. of 200 Pa · s to 10000 Pa · s, an optically anisotropic film can be formed without causing unevenness, and a so-called blocking phenomenon is less likely to occur. . The blocking phenomenon means that, for example, an excessive pressure is applied before the coating solution dries, so that the overlapped films adhere to each other, or additives are unevenly distributed on the film surface even after curing after drying. It means that the films adhere to each other when they come into contact with each other. When a long film is produced and wound up and stored or transported in a roll form, the film surface and the film back surface are laminated and stored for a long time in a pressurized state. As a result of the blocking caused by the pressurization, not only the transparency of the film is impaired, but also disadvantages such as adhesion of the film surface and the film back surface occur. Therefore, it is preferable that blocking is less likely because handling after production becomes easier and total productivity is improved. From the viewpoint that blocking is less likely to occur, the fluoroaliphatic group-containing polymer preferably has a viscosity of 250 to 5000 Pa · s, and more preferably 300 to 1000 Pa · s. In this specification, the “viscosity” of the fluoroaliphatic group-containing polymer is determined by using a VAR-100 rheometer manufactured by Rheology, a distance between gaps of 1.5 mm, a frequency of 1 Hz, a strain of 0.005, and a heating rate of 5 ° C./min. The value measured by the oscillation mode under the condition of nitrogen atmosphere.

In this embodiment, the fluoroaliphatic group-containing polymer is preferably selected from the fluoroaliphatic group-containing polymer represented by the general formula (1). In particular, in the general formula (1), a fluoroaliphatic group-containing polymer in which both R ¹¹ and R ¹² are methyl groups is preferable. In the liquid crystalline composition of the present embodiment, the content of the fluoroaliphatic group-containing polymer is 0.02 to 0.00 with respect to the total mass of the liquid crystalline composition (solid content when prepared as a coating liquid). When it is 50% by mass, blocking is less likely to occur, and from the same viewpoint, 0.03 to 0.30% by mass is more preferable, and 0.05 to 0.20% by mass is even more preferable. .
Other preferred examples of the second fluoroaliphatic-containing polymer to be added as desired, examples of other additives to be added as desired, preferred examples of the liquid crystalline compound, and a method for preparing the composition, etc. Same as above.

[Optically anisotropic film and optical film]
The present invention also relates to an optical film having an optically anisotropic film formed from the liquid crystalline composition and an optically anisotropic layer formed from the liquid crystalline composition. An optically anisotropic film or the like is prepared by using the liquid crystalline composition as a coating liquid, and coating the coating liquid on the surface (the surface of a polymer film or the like serving as a support or the surface of an alignment film). It is preferable that the film is formed in a desired alignment state, and then the alignment state is fixed. The coating liquid can be applied by a known method (eg, wire bar coating method, extrusion coating method, direct gravure coating method, reverse gravure coating method, die coating method).

  After application, the solvent is removed by drying, and the temperature of the liquid crystal compound is controlled as necessary to bring the molecules of the liquid crystal compound into a desired alignment state. Any of horizontal alignment, vertical alignment, hybrid alignment, tilted alignment, and the like may be used. When the discotic liquid crystal compound is hybrid-aligned, the angle between the major axis (disk surface) of the discotic liquid crystal compound molecule and the layer surface, that is, the tilt angle, is increased or decreased in the depth direction of the optically anisotropic film, etc. Let The angle preferably decreases with increasing distance from the applied surface (eg, the alignment film interface). 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.

  The average direction of the major axis (disk surface) of the discotic liquid crystalline compound (average of the major axis direction of each molecule) is generally selected by selecting the discotic liquid crystalline compound or the material of the alignment film, or selecting the rubbing treatment method. By doing so, it can be adjusted. In addition, the major axis (disk surface) direction of the discotic liquid crystalline compound on the surface side (air side) is generally determined depending on the type of the above-described additives used together with the discotic liquid crystalline compound or the discotic liquid crystalline compound, and the fluoroaliphatic It can be adjusted by selecting a group-containing polymer.

  Next, the orientation state is fixed. The alignment state is preferably fixed 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. A photopolymerization reaction is preferred. The coating solution preferably contains a polymerizable monomer or a polymerization initiator that contributes to the fixation of the liquid crystalline compound. As the polymerizable monomer, for example, a compound having a vinyl group, a vinyloxy group, an acryloyl group, and a methacryloyl group is preferable. The amount of the compound added is generally 1 to 50% by weight, preferably 5 to 30% by weight, based on the liquid crystal compound. In addition, when a monomer having 3 or more polymerizable reactive functional groups is mixed and used, adhesion between the alignment film and the optically anisotropic layer can be improved.

  Examples of photopolymerization initiators include α-carbonyl compounds (described in US Pat. Nos. 2,367,661 and 2,367,670), acyloin ethers (described in US Pat. No. 2,448,828), α-hydrocarbon substituted aromatic acyloin compounds ( U.S. Pat. No. 2,722,512), a polynuclear quinone compound (described in U.S. Pat. Nos. 3,046,127 and 2,951,758), a combination of triarylimidazole dimer and p-aminophenyl ketone (described in U.S. 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 (described in US Pat. No. 4,221,970) are included.

  The amount of the photopolymerization initiator used is preferably 0.01 to 20% by weight, more preferably 0.5 to 5% by weight, based on the solid content of the coating solution.

It is preferable to use ultraviolet rays for light irradiation for polymerization of liquid crystalline molecules. The irradiation energy is preferably in the range of ^{20mJ / cm 2 ~50J / cm 2} , more preferably in the range of ^{20mJ / cm 2 ~5000mJ / cm 2} , a range of 100mJ / cm ² ~800mJ / cm ² More preferably. In order to accelerate the photopolymerization reaction, light irradiation may be performed under heating conditions.

  The thickness of the optically anisotropic film and the optically anisotropic layer thus formed is preferably 0.1 to 20 μm, more preferably 0.5 to 15 μm, and 1 to 10 μm. Even more preferably.

  Since the optically anisotropic film and the optically anisotropic layer are formed by coating on the surface, there is an interface with the surface and an air interface on the opposite side. Since fluorine atoms present in the fluoroaliphatic group-containing polymer contribute to the reduction of unevenness, it is preferable that the fluorine atoms are unevenly distributed at the air interface. The presence of fluorine atoms to some extent in the direction up to 10 nm is also important for reducing unevenness. From this viewpoint, when the fluorine atom abundance ratio (ESCA: F / C) at the air interface is 100, the fluorine atom abundance ratio (ESCA: F / C) at a position of 10 nm from the air interface is 2 to 10. Is preferred.

  In producing the optically anisotropic film and the optically anisotropic layer, it is preferable to use an alignment film. The alignment film has a function of defining the alignment direction of the liquid crystalline molecules. As the alignment film, those prepared by subjecting the surface of a film made of modified polyvinyl alcohol to a rubbing treatment are preferable.

  The optical film of the present invention preferably has a substrate for supporting the optically anisotropic layer (hereinafter sometimes referred to as “support”). The substrate is preferably glass or a transparent polymer film. The substrate preferably has a light transmittance (400 to 700 nm) of 80% or more and a haze of 2.0% or less. More preferably, the light transmittance is 86% or more and the haze is 1.0% or less. Examples of the polymer constituting the polymer film include cellulose esters (eg, mono-, di- or triacylate of cellulose), norbornene-based polymers, and polymethyl methacrylate. A commercially available polymer (for norbornene polymers, Arton and Zeonex (both are trade names)) may be used. Moreover, even if it is a conventionally known polymer such as polycarbonate or polysulfone that easily develops birefringence, it is possible to develop birefringence by modifying the molecule as described in International Publication No. 00/26705 pamphlet. Can be used for the optical film of the present invention.

[Polarizer]
The present invention relates to a polarizing plate having the optical film and a polarizer. The polarizing plate can be used for an elliptical polarizing plate in combination with a polarizer which is a linear polarizing film.
An elliptically polarizing plate can be produced by laminating the optical film of the present invention and a polarizing film. Examples of the polarizing film include an iodine polarizing film, a dye polarizing film using a dichroic dye, and a polyene polarizing film. The iodine polarizing film and the dye polarizing film are generally produced using a polyvinyl alcohol film. The polarization axis of the polarizing film corresponds to a direction perpendicular to the stretching direction of the film.

  It is preferable that the optical film is laminated on one surface of the polarizing film and a protective film is laminated on the other surface. The protective film is preferably a transparent protective film having a light transmittance of 80% or more. As the transparent protective film, generally a cellulose ester film, preferably a triacetyl cellulose film is used. The cellulose ester film is preferably formed by a solvent cast method. The thickness of the protective film is preferably 20 to 500 μm, and more preferably 50 to 200 μm.

[Liquid Crystal Display]
The present invention may be used in a liquid crystal display device using the optical film of the present invention as an optical compensation sheet and / or the polarizing plate of the present invention as an elliptically polarizing plate. TN (Twisted Nematic), IPS (In-PDane Switching), FDC (FerroElectric Dicted CrydD), OCB (OpticaDy Compensatory Bend), STN (SuperTweetDV) The liquid crystal display device can be used in various display modes.

  The present invention will be described more specifically with reference to the following examples. The materials, reagents, amounts and ratios of substances, operations, and the like shown in the following examples can be appropriately changed without departing from the gist of the present invention. Therefore, the scope of the present invention is not limited to the following specific examples. In the following, all parts and% are based on mass unless otherwise specified.

[Example 1]
A cellulose triacetate film (TAC film) was immersed in a 2.0N potassium hydroxide solution (25 ° C.) for 2 minutes, neutralized with sulfuric acid, washed with pure water, and dried. On the TAC film, an alignment film coating solution having the following composition was coated at a coating amount of 28 ml / m ² with a # 16 wire bar coater. Drying was performed with warm air of 60 ° C. for 60 seconds, and further with warm air of 90 ° C. for 150 seconds.
(Orientation film coating solution composition)
The following modified polyvinyl alcohol 10 parts by weight Water 371 parts by weight Methanol 119 parts by weight Glutaraldehyde (crosslinking agent) 0.5 parts by weight

  The alignment film was rubbed in a direction parallel to the slow axis of the TAC film.

(Formation of optically anisotropic layer)
A coating solution 1 having the following composition was prepared.
27.46% by mass of the following discotic liquid crystalline compound
Ethylene oxide modified trimethylolpropane triacrylate (V # 360, manufactured by Osaka Organic Chemical Co., Ltd.) 2.72% by mass
Cellulose acetate butyrate (CAB551-0.2, manufactured by Eastman Chemical Co.) 0.23% by mass
Cellulose acetate butyrate (CAB531-1, manufactured by Eastman Chemical Co.) 0.07% by mass
Exemplary polymer P-1 (MW = 15000) 0.07 mass%
(First fluoroaliphatic group-containing polymer of the general formula (1))
The following polymer P-0 (MW = MW = 13000) 0.07 mass%
(Second fluoroaliphatic group-containing polymer)
Photopolymerization initiator (Irgacure 907, manufactured by Ciba Geigy) 0.90% by mass
Sensitizer (Kayacure DETX, manufactured by Nippon Kayaku Co., Ltd.) 0.30% by mass

  The above components are mixed and dissolved in methyl ethyl ketone (68.31% by mass) to prepare a coating solution 1, which is continuously coated on the alignment film with a # 3.6 wire bar at 130 ° C. For 2 minutes to orient the discotic liquid crystalline compound. Next, UV irradiation was performed for 1 minute using a 120 W / cm high-pressure mercury lamp at 100 ° C. to polymerize the discotic liquid crystalline compound. Then, it stood to cool to room temperature. Thus, the optical film 1 was produced.

  As shown in Table 1 below, the fluoroaliphatic group-containing polymer P-1 was changed to various polymers, and the coating solutions 2 to 5 were prepared in the same manner as the coating solution 1 except that the addition amount was changed. Each of them was used in the same manner as the optical film 1 to produce optical films 2 to 5.

(Appearance evaluation)
About the produced optical films 1-5, the presence or absence of the nonuniformity was observed with the following method, and the external appearance was evaluated on the following references | standards.
(Preparation of polarizing plate)
The produced optical film was affixed on one side of the polarizer on the polymer substrate (TAC film) surface using a polyvinyl alcohol-based adhesive. Moreover, the saponification process was performed to the 80-micrometer-thick triacetyl-cellulose film (TD-80U: Fujifilm Corporation make), and it affixed on the other side of the polarizer using the polyvinyl alcohol-type adhesive agent. The transmission axis of the polarizer and the slow axis of the polymer substrate were arranged in parallel. The transmission axis of the polarizer and the slow axis of the triacetyl cellulose film were arranged so as to be orthogonal to each other. In this way, a polarizing plate was produced.
(Evaluation of unevenness on a flat high-intensity light source)
The polarizing plate was bonded to a planar high-intensity light source (FP901 high-intensity planar light source manufactured by Gunma Ushio Electric Co., Ltd.) and compared with a level sample serving as a judgment standard, and unevenness was evaluated with the naked eye.

  From the results described in Table 1 above, it is understood that the optical films 1 and 2 in which the optically anisotropic layer is formed using the fluoroaliphatic group-containing polymer represented by the general formula (1) have no unevenness. It was.

(Optical film blocking evaluation)
About the optical films 1-3 produced above, blocking evaluation was performed with the following method. The viscosity of P-1 and P-2 at 25 ° C. is about 30 Pa · s, while the viscosity of P-18 at the same temperature is 309 Pa · s.
(Production of evaluation film)
The produced optical film is cut into a size of 5 cm × 5 cm and two sheets are overlapped. A rubber plate having an area of 4 cm × 1 cm is placed thereon, and a weight of 10 kg load is further placed thereon and left for 3 hours. The sample for blocking evaluation was produced by removing the weight and the rubber plate.
(Evaluation of blocking)
The coating surface of the produced blocking evaluation film was observed with a high-intensity light source, and compared with a level sample serving as a judgment criterion, unevenness was evaluated with the naked eye.
As a result, in optical films 1 and 2, blocking that caused adhesion marks on the film surface occurred, but in optical film 3, no blocking phenomenon was observed.

[Example 2]
About Example monomer A2-2, Example monomer B2-2, and Example monomer C-27, it superposed | polymerized by changing various preparation amounts, and a, b, and c (mass% which respectively show polymerization ratio) of a following formula are Various values of fluoroaliphatic group-containing methacrylic polymers (polymers of formula (1)) PM-1 to 10 were synthesized.
In addition, with respect to the exemplified monomer A1-2, the exemplified monomer B1-2, and the exemplified monomer C-26, polymerization was carried out with various amounts of charge, and a, b, and c in the following formulas are various values of fluoroaliphatic Group-containing acrylic polymers (polymers of formula (1)) PA-1 to 10 were synthesized.

Optical films 10 to 20 were produced in the same manner except that each of the synthesized polymers was used in place of the polymer P-1, and the appearance (presence / absence of unevenness) of the optical film was evaluated in the same manner as described above. However, more detailed evaluation was performed according to the following criteria.
(Preparation of polarizing plate)
The produced optical film was affixed on one side of the polarizer on the polymer substrate (TAC film) surface using a polyvinyl alcohol-based adhesive. Moreover, the saponification process was performed to the 80-micrometer-thick triacetyl-cellulose film (TD-80U: Fujifilm Corporation make), and it affixed on the other side of the polarizer using the polyvinyl alcohol-type adhesive agent. The transmission axis of the polarizer and the slow axis of the polymer substrate were arranged in parallel. The transmission axis of the polarizer and the slow axis of the triacetyl cellulose film were arranged so as to be orthogonal to each other. In this way, a polarizing plate was produced.
(Evaluation with TN liquid crystal cell)
A pair of polarizing plates provided in a liquid crystal display device (V260B1, manufactured by Chimei Electronics Co., Ltd.) using a TN type liquid crystal cell is peeled off, and instead of the polarizing plate produced in Example 1, the optical film is a liquid crystal A single sheet was attached to the observer side and the backlight side through an adhesive so as to be on the cell side. The transmission axis of the polarizing plate on the viewer side and the transmission axis of the polarizing plate on the backlight side were arranged to be in the O mode.
(Evaluation of unevenness on LCD panel)
The display panel of the liquid crystal display device was adjusted to a halftone on the entire surface, and compared with a level sample serving as a judgment criterion, unevenness was evaluated with the naked eye.
Table 2 below shows the values of a / (a + b), (a + b), and unevenness evaluation results of the polymers used. The numerical value of the evaluation result in the table is the unevenness evaluation score determined by comparison with the sample. The smaller the numerical value, the more the unevenness is.

  From the results shown in Table 2 above, among the fluoroaliphatic group polymers represented by the general formula (1), the value of a / (a + b) is 0.2 to 0.8 and / or (a + b) It was found that when a fluoroaliphatic group polymer having a / (a + b + c) of 20 to 50% by mass is used, an optical film having particularly small unevenness and excellent appearance characteristics can be produced.

[Example 3]
About the coating liquids 1-4 used for preparation of each optical film 1-4 produced in the said Example 1, the surface tension was continuously measured for the predetermined time by the maximum bubble pressure method. For measurement, a surface tension meter “MPT2” manufactured by LAUDA was used.
Furthermore, for the coating liquid 1, the coating liquids 1a and 1b prepared in the same manner except that the concentration of each component was changed, and for the coating liquid 2, the coating liquid 2a prepared in the same manner except that the concentration of each component was changed. And 2b are prepared, and the surface tension is continuously measured in the same manner. Furthermore, optical films 1a and 1b and optical films 2a and 2b were produced using the respective coating solutions in the same manner as in Example 1.
About the optical films 1 and 2 produced in Example 1, and the optical films 1a, 1b, 2a, and 2b, the appearance (presence of unevenness) was evaluated in the same manner as described above. However, more detailed evaluation was performed according to the following criteria.
The measured values of the surface tension of each coating solution and the appearance evaluation results of each optical film are shown in Table 3 below.

  From the results shown in Table 3 above, it is considered that the coating liquid containing the fluoroaliphatic group polymer represented by the general formula (1) has a low surface tension at the initial stage of drying, and as a result, unevenness is reduced. . In particular, it was found that when a coating solution having a surface tension ratio (10 milliseconds / 1000 milliseconds) of 1.0 to 1.20 was used, unevenness was further reduced and an optical film having an excellent appearance was obtained.

[Example 4]
Various coating liquids were similarly applied to the coating liquid 1 used in the production of the optical film 1 in Example 1, except that the concentration of the exemplified polymer P-1 (the fluoroaliphatic group-containing polymer of the formula (1)) was changed. And various optical films were prepared using the coating solution. The appearance of these optical films was evaluated in the same manner as described above. For each optical film, the solid content concentration C of the polymer P-1 and the fluorine content F of the polymer P-1 (F = 0.08% in the example polymer P-1) in the coating solution used for the production thereof The product C × F is taken on the horizontal axis, and the score of the appearance evaluation result of the optical film is plotted on the vertical axis, which are summarized in the graph of FIG. The appearance tolerance level is 3 or less.
From the result shown in the graph of FIG. 1, the value of C × F of the polymer P-1 in the coating solution has an influence on the appearance characteristics of the optical film, and C × F is 0.05 to 0.12. It was found that in the range, in particular, unevenness was reduced and an optical film excellent in appearance was obtained.

[Example 5]
For the optical films 1, 3 and 4 produced in Example 1, the distribution of fluorine atoms in each optically anisotropic layer was examined by measuring ESCA. The results are shown in Table 4 below. The ratio of fluorine atoms in Table 4 is that the fluorine atom concentration at the air interface (0 nm) of the optically anisotropic layer of the optical film 1 is 100, and the fluorine atoms at the 5 nm position and 10 nm position in the depth direction. The atomic concentration is shown as a relative value. Also in the optical films 3 and 4, the fluorine atom concentration at the air interface (0 nm) of the optically anisotropic layer of the optical film 1 was 100, and the fluorine atom concentration at each depth was shown as a relative value.

  From the results shown in Table 4 above, the optical film 1 of the present invention has fluorine atoms unevenly distributed at the air interface and is distributed to some extent in the depth direction (100 at the air interface at a position 10 nm from the air interface). It can be understood that there are about 2 to 10). By using the fluoroaliphatic group-containing polymer represented by the formula (1), the distribution of such fluorine atoms is possible, and as a result, the appearance of the optical film is considered to be improved.

It is a graph which shows the result plotted about the optical film produced in Example 4 on the horizontal axis | shaft and the score of the external appearance evaluation of each optical film on the vertical axis | shaft of the coating liquid used for preparation of each optical film. .

Claims (14)

Liquid crystalline composition containing at least one liquid crystal compound and at least one fluoroaliphatic group-containing polymer represented by the following general formula (1):

In the general formula (1), i and j each represent an integer of 1 or more, meaning that each repeating unit includes i and j types, respectively; M is derived from an ethylenically unsaturated monomer, and k (k Is an integer greater than or equal to 1) types of repeating units; a, b and c are mass percentages representing a polymerization ratio, Σai represents a numerical value of 1 to 98% by mass, and Σbj represents a numerical value of 1 to 98% by mass. Σck represents a numerical value of 1 to 98% by mass; R ¹¹ and R ¹² each represent a hydrogen atom or a methyl group; X ¹ and X ² each represent an oxygen atom, a sulfur atom, or —N (R ¹³ ) -, R ¹³ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; m1 and m2 each represent an integer of 1 to 6; and n1 represents an integer of 0 to 3. The liquid crystalline composition according to claim 1, wherein Σai / (Σai + Σbj) is 0.2 to 0.8. The liquid crystalline composition according to claim 1 or 2, wherein Σai + Σbj is 20 to 50% by mass. 4. The liquid crystalline composition according to claim 1, wherein n1 is 0 in the general formula (1). 5. The liquid crystalline composition according to claim 1, wherein the fluoroaliphatic group-containing polymer has a viscosity at 25 ° C. of 200 Pa · s to 10,000 Pa · s. Content of the said fluoro aliphatic group containing polymer is 0.02-0.50 mass%, The liquid crystalline composition of any one of Claims 1-5 characterized by the above-mentioned. Surface tension ratio of the 10m sec and 1000m seconds measured at the maximum bubble pressure method (10m sec / 1000m sec) is, any one of claims 1 to 6, characterized in that a 1.00 to 1.20 The liquid crystalline composition described in 1. A product C × F of a concentration C% by mass of the fluoroaliphatic group-containing polymer and a fluorine content F% in the fluoroaliphatic group-containing polymer is 0.05 to 0.12. Item 8. The liquid crystalline composition according to any one of items 1 to 7 . The liquid crystal compound, liquid crystal composition according to any one of claims 1-8, characterized in that the discotic compound. An optically anisotropic film formed from the composition according to any one of claims 1 to 9 . When the fluorine atom abundance ratio (ESCA: F / C) at the air interface is 100, the fluorine atom abundance ratio (ESCA: F / C) at a position of 10 nm from the air interface is 2-10. The optically anisotropic film according to claim 10 . The optical film having an optical anisotropic layer formed from liquid crystal composition according to any one of claims 1-9. A polarizing plate comprising the optical film according to claim 12 and a polarizer. A liquid crystal display device comprising the optical film according to claim 12 and / or the polarizing plate according to claim 13 .

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