TW201441306A - Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal display device - Google Patents

Abstract

A liquid crystal alignment agent is provided, which manufactures a liquid crystal display device having high reliability. The liquid crystal alignment agent includes at least one polymer (A) selected from a group consisting of polyamic acid, polyamic acid ester and polyimide, and a blocked isocyanate (B-1) which is polyfunctional and has aromatic ring.

Description

Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element, and more particularly to a technique for improving the reliability of a liquid crystal display element.

Conventionally, liquid crystal display elements have developed various driving methods in which electrode structures or physical properties of liquid crystal molecules used are different, and for example, Twisted Nematic (TN) type or Super Twisted Nematic (STN) is known. Vertical Alignment (VA), Multi-domain Vertical Alignment (MVA), In-Plane Switching (IPS), Fringe Field Switching (FFS) Various types of liquid crystal display elements such as an optically compensated bend type (Optically Compensated Bend, OCB type). These liquid crystal display elements have a liquid crystal alignment film for aligning liquid crystal molecules. The material of the liquid crystal alignment film is a polymer such as polyacrylamide, polyimine, polyphthalate, polyester, or polyorganosiloxane, in which various properties such as heat resistance, mechanical strength, and affinity for liquid crystal are used. In a good aspect, polylysine or polyimine is usually used.

In recent years, liquid crystal display elements have not only been used for display devices such as personal computers as before, but also used in, for example, liquid crystal televisions or car navigation systems, mobile phones, smart phones, information displays, and the like. use. In addition, a liquid crystal display element is required to be able to withstand high-reliability and long-term use, and various liquid crystal alignment agents which satisfy the above-mentioned requirements have been proposed (for example, refer to Patent Document 1 and Patent Document 2). Patent Document 1 and Patent Document 2 disclose a liquid crystal alignment agent containing not only a polyimine having a carboxyl group as a polymer component but also a first-order amine group and a nitrogen-containing aromatic heterocyclic ring and a first-order amine bond. A primary amine compound attached to an aliphatic hydrocarbon group is used as an additive component.

[Prior Art Literature]

[Patent Literature]

[Patent Document 1] International Publication No. 2008/013285

[Patent Document 2] International Publication No. 2009/084665

Further, the demand for higher performance of the liquid crystal display element is further improved, and the liquid crystal alignment film is required to have deterioration and deterioration after use for a long period of time, and it is preferable to exhibit a highly reliable liquid crystal alignment film which is a performance of the liquid crystal alignment film. .

The present invention has been made in view of the above problems, and a main object thereof is to provide a liquid crystal alignment agent which can improve the reliability of a liquid crystal display element. In addition, another object is to provide a highly reliable liquid crystal display element.

In order to solve the problems of the prior art as described above, the present inventors have found that the above-mentioned problems can be solved by including a specific compound as an additive component in a liquid crystal alignment agent, and the present invention has been completed. Specifically, the present invention provides the following liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element.

An aspect of the present invention provides a liquid crystal alignment agent comprising: at least one polymer (A) selected from the group consisting of polylysine, polyphthalate, and polyamidene; And a polyfunctional blocked isocyanate compound (B-1) having an aromatic ring.

One aspect of the present invention provides a liquid crystal alignment film formed using the liquid crystal alignment agent described above. Then, another aspect of the present invention provides a liquid crystal display element including the liquid crystal alignment film.

According to the liquid crystal alignment agent of the present invention, by containing the compound (B-1) as an additive component, it is possible to form a liquid crystal display element which can obtain a low voltage holding ratio after long-term use and has high reliability. Liquid crystal alignment film.

Hereinafter, each component contained in the liquid crystal alignment agent of the present invention and other components arbitrarily formulated as needed will be described.

<Polymer (A)>

The liquid crystal alignment agent of the present invention contains at least one polymer (A) selected from the group consisting of polylysine, polyphthalate, and polyimine as a polymer component.

[polyglycolic acid]

Polylysine which is the polymer (A) of the present invention (hereinafter also referred to as "polyproline (A)") can be obtained, for example, by reacting a tetracarboxylic dianhydride with a diamine.

(tetracarboxylic dianhydride)

Examples of the tetracarboxylic dianhydride used for the synthesis of the polyamic acid (A) of the present invention include aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride. Specific examples of the tetracarboxylic dianhydride include aliphatic monocarboxylic dianhydride: 1,2,3,4-butanetetracarboxylic dianhydride; and alicyclic tetracarboxylic dianhydride. : 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a,4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro 8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, 3-oxabicyclo[ 3.2.1] Octane-2,4-dione-6-spiro-3'-(tetrahydrofuran-2',5'-dione), 5-(2,5-dioxotetrahydro-3- Furyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2:3,5:6- Anhydride, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, 4,9-dioxatricyclo[5.3.1.0 ^2,6 ] Monoalkane-3,5,8,10-tetraketone, cyclohexanetetracarboxylic dianhydride, cyclopentane tetracarboxylic dianhydride, etc.; aromatic tetracarboxylic dianhydride, for example, pyromellitic dianhydride In addition, the tetracarboxylic dianhydride etc. which are described in Unexamined-Japanese-Patent No. 2010-97188 can be used. Further, the tetracarboxylic dianhydride may be used alone or in combination of two or more.

The tetracarboxylic dianhydride for synthesizing the polyamic acid (A) preferably contains an alicyclic tetracarboxylic dianhydride in terms of solubility in a solvent or transparency. Among them, it is more preferable to contain at least one selected from the group consisting of the following tetracarboxylic dianhydrides (hereinafter also referred to as "specific tetracarboxylic dianhydride"): 2,3,5-tricarboxycyclopentyl acetic acid Dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1 ,3-dione, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1] ,2-c]furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, 1,2,4, 5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, and 1,2,3,4-cyclobutanetetracarboxylic dianhydride; especially preferably comprising At least one of the group consisting of the following tetracarboxylic dianhydrides (hereinafter also referred to as "specific tetracarboxylic dianhydride"): 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 2, 4, 6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, 1,2,3,4-cyclobutane IV A carboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, and 1,2,3,4-cyclopentane tetracarboxylic dianhydride.

The tetracarboxylic dianhydride for synthesizing polyamic acid preferably contains 20 mol% or more of the specific tetracarboxylic dianhydride, more preferably, based on the total amount of the tetracarboxylic dianhydride used for the synthesis. It is contained in an amount of 50 mol% or more, and particularly preferably 80 mol% or more.

(diamine)

Examples of the diamine for synthesizing the polyamic acid (A) of the present invention include an aliphatic diamine, an alicyclic diamine, an aromatic diamine, a diamine organic decane, and the like. Specific examples of the diamine include aliphatic m-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine. And the alicyclic diamine may, for example, be 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), 1,3-bis(aminomethyl)cyclohexane Examples of the aromatic diamine include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, and 1,5-diamino group. Naphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 2,7- Diamino hydrazine, 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 9,9-bis(4-amino group Phenyl) guanidine, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4' -(p-phenylenediphenylene)diphenylamine, 4,4'-(meta-phenyldiisopropylidene)diphenylamine, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-di Amino acridine, 3,6-diaminocarbazole, N-methyl-3 ,6-Diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N,N'-bis(4-amino Phenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, 1,4-bis-(4-aminophenyl)-pyridazine , 1-(4-Aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indole-5-amine, 1-(4-aminophenyl)-2, 3-dihydro-1,3,3-trimethyl-1H-indol-6-amine, 3,5-diaminobenzoic acid, cholesteryloxy-3,5-diaminobenzene, gall Decenyloxy-3,5- Diaminobenzene, cholestyloxy-2,4-diaminobenzene, cholestyloxy-2,4-diaminobenzene, 3,5-diaminobenzoic acid cholesteryl Ester, cholesteryl 3,5-diaminobenzoic acid, lanosteryl 3,5-diaminobenzoic acid, 3,6-bis(4-aminobenzimidyloxy) cholate Decane, 3,6-bis(4-aminophenoxy)cholestane, 4-(4'-trifluoromethoxybenzylideneoxy)cyclohexyl-3,5-diaminobenzoic acid Acid ester, 4-(4'-trifluoromethyl benzhydryloxy)cyclohexyl-3,5-diaminobenzoate, 1,1-bis(4-((aminophenyl)) Phenyl)-4-butylcyclohexane, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-heptylcyclohexane, 1,1-double ( 4-((Aminophenoxy)methyl)phenyl)-4-heptylcyclohexane, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-( 4-heptylcyclohexyl)cyclohexane, 2,4-diamino-N,N-diallylaniline, 4-aminobenzylamine, 3-aminobenzylamine, and the following formula ( D-1)

(In the formula (D-1), X ^I and X ^II are each independently a single bond, -O-, -COO- or -OCO-, and R ^I and R ^II are each independently an alkane having 1 to 3 carbon atoms. Base, a is 0 or 1, b is an integer from 0 to 2, c is an integer from 1 to 20, and n is 0 or 1; where a and b are not 0 at the same time.)

Examples of the compound to be represented, and examples of the diamine-based organooxane include 1,3-bis(3-aminopropyl)-tetramethyl and decane, and the like, and other patents can be used. The diamine described in Japanese Laid-Open Patent Publication No. 2010-97188. As for the other diamine, one type of these diamines may be used alone or two or more types may be used in combination.

The divalent group represented by "-X ^I -(R ^I -X ^II ) _n -" in the formula (D-1) is preferably an alkanediyl group having a carbon number of 1 to 3, *-O-, * -COO- or *-OC ₂ H ₄ -O- (wherein the bond labeled "*" is bonded to the diaminophenyl group). Specific examples of the group "-C _c H _2c+1 " include, for example, methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-decyl , n-decyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nine Alkyl, n-icosyl, and the like. The two amine groups in the diaminophenyl group are preferably located at the 2,4-position or the 3,5-position relative to other groups.

Specific examples of the compound represented by the formula (D-1) include a compound represented by the following formula (D-1-1) to the formula (D-1-5), and the like.

[Molecular weight regulator]

In the case of synthesizing polyamic acid, a terminal-modified polymer can be synthesized using an appropriate molecular weight modifier while using the tetracarboxylic dianhydride and the diamine as described above. By forming the terminal-modified polymer, the coating property (printability) of the liquid crystal alignment agent can be further improved without impairing the effects of the present invention.

Examples of the molecular weight modifier include an acid monoanhydride, a monoamine compound, and a monoisocyanate compound. Specific examples of the compound include, for example, maleic anhydride, and the acid monoanhydride. Phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl succinic anhydride, n-hexadecyl succinic anhydride, etc.; monoamine compounds such as Examples thereof include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, and n-octylamine; and examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

The use ratio of the molecular weight modifier is preferably 20 parts by weight or less, and more preferably 10 parts by weight or less, based on 100 parts by weight of the total of the tetracarboxylic dianhydride and the diamine to be used.

[Synthesis of polyglycine]

The ratio of the tetracarboxylic dianhydride to the diamine to be used in the synthesis reaction of the polyaminic acid of the present invention is preferably 1 equivalent to the amine group of the diamine, and the acid anhydride group of the tetracarboxylic dianhydride is 0.2 equivalent to 2 equivalents. The ratio is more preferably 0.3 to 1.2 equivalents.

The synthesis reaction of polylysine is preferably carried out in an organic solvent. The reaction temperature at this time is preferably -20 ° C to 150 ° C, and more preferably 0 ° C to 100 ° C. Further, the reaction time is preferably from 0.1 to 24 hours, more preferably from 0.5 to 12 hours.

Here, examples of the organic solvent include an aprotic polar solvent, a phenol solvent, an alcohol, a ketone, an ester, an ether, a halogenated hydrocarbon, and a hydrocarbon. Specific examples of the organic solvent include, for example, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, and N-ethyl-2-pyrrolidone. , N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl hydrazine, γ-butyrolactone, tetramethylurea, hexamethylphosphonium triamine, etc.; Examples of the phenol-based solvent include phenol, m-cresol, xylenol, and halogenated phenol; and examples of the alcohol include methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, and propylene glycol, and 1,4. - butanediol, triethylene glycol, ethylene glycol monomethyl ether, etc.; the ketone may, for example, be acetone or methyl Ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.; examples of the ester include ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, and methyl methoxypropionate. And ethyl ethoxy propionate, diethyl oxalate, diethyl malonate, isoamyl propionate, isoamyl isobutyrate, etc.; the ether is, for example, diethyl ether or ethylene glycol. Methyl ether, ethylene glycol ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol-n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethyl ether Alcohol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, Diisoamyl ether or the like; examples of the halogenated hydrocarbon include dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene, and the like; Examples of the hydrocarbon include hexane, heptane, octane, benzene, toluene, xylene, and the like.

Among these organic solvents, one or more selected from the group consisting of an aprotic polar solvent and a phenol solvent (the organic solvent of the first group), or an organic solvent selected from the first group is preferably used. One or more kinds of one or more kinds selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons (organic solvents of the second group). In the latter case, the use ratio of the organic solvent of the second group is preferably 50% by weight or less, more preferably 40% by weight, based on the total amount of the organic solvent of the first group and the organic solvent of the second group. Hereinafter, it is especially preferably 30% by weight or less. The amount (a) of the organic solvent to be used is preferably an amount of the total amount (a+b) of the reaction solution, and the total amount (b) of the tetracarboxylic dianhydride and the diamine is 0.1% by weight to 50% by weight.

A reaction solution obtained by dissolving polyamic acid (A) was obtained in the above manner. The reaction solution may be directly supplied to the preparation of the liquid crystal alignment agent, or the polyamic acid (A) contained in the reaction solution may be isolated and then supplied to the liquid crystal alignment agent, or the isolated polyamine may be used. The acid (A) is purified and then supplied to the preparation of the liquid crystal alignment agent. In the closed loop of polylysine (A) In the case of the polyimine, the reaction solution may be directly supplied to the dehydration ring closure reaction, or the polylysine (A) contained in the reaction solution may be isolated and then supplied to the dehydration ring closure reaction, or The isolated polylysine (A) can also be purified and then supplied to a dehydration ring closure reaction. The isolation and purification of polyamic acid (A) can be carried out according to a known method.

[polyamidomate]

The polyglycolate (hereinafter also referred to as polyphthalate (A)) as the polymer (A) can be obtained, for example, by the following method: [I] by the polymerization obtained by the synthesis reaction a method for synthesizing proline (A) with a hydroxyl group-containing compound, a halide, an epoxy group-containing compound, or the like; [II] a method of reacting a tetracarboxylic acid diester with a diamine; and [III] A method of reacting a tetracarboxylic acid diester dihalide with a diamine.

Here, examples of the hydroxyl group-containing compound used in the method [I] include alcohols such as methanol, ethanol, and propanol; and phenols such as phenol and cresol. Further, examples of the halide include methyl bromide, ethyl bromide, octadecyl octadecyl, methyl chloride, chlorooctadecane, 1,1,1-trifluoro-2-iodoethane, and the like. Examples of the compound include propylene oxide and the like. The tetracarboxylic acid diester used in the method [II] can be obtained, for example, by subjecting the tetracarboxylic dianhydride to ring opening using the alcohol. Further, the tetracarboxylic acid diester dihalide used in the method [III] can be obtained by reacting a tetracarboxylic acid diester obtained in the above manner with a suitable chlorinating agent such as sulfinium chloride. The diamine used in the method [II] and the method [III] may, for example, be a diamine or the like used in the synthesis of the polyamic acid (A). Further, the polyphthalate (A) may have only a phthalate structure, or may be a partial ester compound in which a valeric acid structure and a phthalate structure coexist.

[polyimine]

Polyimine as the polymer (A) (hereinafter also referred to as "polyimine (A)") can be subjected to dehydration ring closure by the poly (proline) acid (A) synthesized in the above manner. Obtained by amination.

The polyimine (A) may be a fully ruthenium imine compound obtained by dehydration ring closure of the proline structure of the polyamic acid (A) as a precursor thereof, or may be only ruthenium. A part of the structure of the amine acid undergoes a dehydration ring closure to form a partial quinone imide of the proline structure and the quinone ring structure. The polyimine (A) preferably has a sulfhydrylation ratio of 30% or more, more preferably 50% to 99%, and particularly preferably 60% to 99%. The ruthenium imidation ratio is a total of the number of the guanidine structure of the polyimine and the number of the quinone ring structure, and the ratio of the number of the quinone ring structure is expressed as a percentage. Here, a part of the quinone ring may be an isoindole ring.

The dehydration ring closure of polyamic acid (A) is preferably carried out by a method of heating poly-proline (A) or dissolving poly-proline (A) in an organic solvent in which the solution is dissolved. A method of adding a dehydrating agent and a dehydration ring-closing catalyst, if necessary, heating. Among them, it is preferred to use the latter method.

In the method of adding a dehydrating agent and a dehydration ring-closure catalyst to the solution of the polyamic acid (A), an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent used is preferably from 0.01 mol to 20 mol based on 1 mol of the proline structure of the polyamic acid (A). As the dehydration ring-closing catalyst, for example, a tertiary amine such as pyridine, trimethylpyridine, dimethylpyridine or triethylamine can be used. The amount of the dehydration ring-closure catalyst used is preferably set to 0.01 mol to 10 mol with respect to 1 mol of the dehydrating agent to be used. The organic solvent used in the dehydration ring-closure reaction is exemplified as an organic solvent exemplified as an organic solvent for synthesizing polyglycolic acid (A). The reaction temperature of the dehydration ring closure reaction is preferably from 0 ° C to 180 ° C, more preferably from 10 ° C to 150 ° C. The reaction time is preferably from 1.0 to 120 hours, more preferably from 2.0 to 30 hours.

The reaction solution containing the polyimine (A) was obtained in the above manner. The reaction solution can be It can be directly supplied to the preparation of the liquid crystal alignment agent, and can also be used for preparing the liquid crystal alignment agent after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, or can be provided to the liquid crystal alignment agent after isolating the polyimine (A). The preparation, or the isolated polyimine (A) can also be purified and then supplied to the preparation of the liquid crystal alignment agent. These purification operations can be carried out in accordance with a known method. Further, the method for synthesizing the polyimine (A) is not limited to the above method, and may be carried out, for example, by hydrazylation of the polyphthalate (A).

The polyamic acid, polyphthalate, and polyimine as the polymer (A) obtained in the above manner are preferably 10 mPa when it is made into a solution having a concentration of 10% by weight. s~800mPa. The solution viscosity of s is more preferably 15 mPa. s~500mPa. s solution viscosity of the compound. Further, the solution viscosity (mPa.s) of the polymer (A) means preparation for a good solvent (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) using the polymer (A). The polymer solution having a concentration of 10% by weight was measured at 25 ° C using an E-type rotational viscometer (trade name).

In addition, the polystyrene acid, polyphthalate, and polyimine which are the polymer (A) are preferably a polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography of 500~. 100,000, more preferably 1,000 to 50,000.

<Block isocyanate compound (B)>

The polyfunctional block isocyanate compound (B) (hereinafter also simply referred to as "compound (B)") is exemplified as the additive component. Here, the "block isocyanate compound" means that a compound having an isocyanato group (-NCO) (isocyanate compound) is reacted with a compound such as a compound having active hydrogen or an active methylene compound at room temperature. Become an inert compound. Further, the term "active hydrogen" means a hydrogen atom bonded to an atom other than a carbon atom, and preferably means a bonding energy. A hydrogen atom lower than the carbon-hydrogen bond of the polymethylene group.

The compound (B) may be a low molecular compound obtained by a reaction of a polyfunctional isocyanate compound and a block agent, or may be a polyisocyanate and a block agent obtained by polymerizing a polyfunctional isocyanate compound. A polymer compound obtained by the reaction. The compound (B) is preferably a low molecular compound, and examples thereof include a compound represented by the following formula (b-1).

(In the formula (b-1), R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms; X ¹ is an n-valent organic group having 1 to 30 carbon atoms; and X ² is a monovalent number of 1 to 30 carbon atoms. The organic group; n is an integer of 2-6; wherein a plurality of R ¹ in the formula may be the same or different, and a plurality of X ² may be the same or different.

The compound (B) is preferably a polyfunctional block isocyanate compound (B-1) having an aromatic ring, from the viewpoint of appropriately obtaining an effect of being less likely to cause deterioration in performance of the liquid crystal alignment film accompanying long-term use. Specifically, a compound represented by the following formula (b1-1) is preferable.

(In the formula (b1-1), X ¹¹ is an n-valent organic group having an aromatic ring; and R ¹ , X ² and n have the same meanings as the above formula (b-1).)

Examples of the monovalent hydrocarbon group having 1 to 6 carbon atoms in R ¹ in the above formula include a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. Here, the "chain hydrocarbon group" as used herein means a hydrocarbon group which does not contain a cyclic structure in the main chain but is composed only of a chain structure. Among them, the chain structure may be linear or branched. The "alicyclic hydrocarbon group" means a hydrocarbon group containing only an alicyclic hydrocarbon structure and containing no aromatic ring structure. Among them, it is not necessarily required to be composed only of the structure of the alicyclic hydrocarbon, and also includes a hydrocarbon group having a chain structure in a part thereof. In addition, the "aromatic hydrocarbon group" means a hydrocarbon group containing an aromatic ring structure as a ring structure. Among them, it is not necessarily required to be composed only of an aromatic ring structure, and a structure of a chain structure or an alicyclic hydrocarbon may be contained in a part thereof.

Specific examples of the R ¹ include a carbon number of 1 to 6 such as a methyl group, an ethyl group, a propyl group, a butyl group or a pentyl group; and a carbon number such as a vinyl group, a propenyl group or a butenyl group; An alkenyl group of 1 to 6; an alkynyl group having 1 to 6 carbon atoms such as an ethynyl group or a propynyl group; and these chain hydrocarbon groups may be linear or branched. Further, examples of the alicyclic hydrocarbon group include a cyclopentyl group and a cyclohexyl group; and examples of the aromatic hydrocarbon group include a phenyl group and the like.

In the chain hydrocarbon group, R ¹ is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. In particular, when R ¹ is a hydrogen atom, it is preferable that X ^{2 is} easily removed from the compound by heat treatment, and the isocyanate group is easily regenerated.

Examples of the n-valent organic group having 1 to 30 carbon atoms in X ¹ include a hydrocarbon group such as a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group, or -O-, - between the carbon-carbon bonds in the hydrocarbon group. A group having a functional group such as COO-, -CO-, -NHCO-, -S-, or -NH-, a heterocyclic group or the like. Further, each of these groups may have a substituent such as a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom or an iodine atom) or an alkoxy group.

Here, examples of the n-valent chain hydrocarbon group include, for example, methane, ethane, propane, butane, pentane, hexane, heptane, octane, decane, decane, dodecane, tetradecane, and a group in which n hydrogen atoms are removed from an alkane having 1 to 30 carbon atoms such as a decane; and a group in which n hydrogen atoms are removed from an olefin having 1 to 30 carbon atoms such as ethylene, propylene, butene or pentene; A group in which n hydrogen atoms are removed from an alkyne having 1 to 30 carbon atoms such as acetylene or methylacetylene, and these groups may be linear or branched. In addition, examples of the n-valent alicyclic hydrocarbon group include a group in which n hydrogen atoms are removed from an alicyclic hydrocarbon having 3 to 30 carbon atoms such as cyclopropane, cyclopentane, cyclohexane or methylcyclohexane; Examples of the n-valent aromatic hydrocarbon group include aromatic groups having 5 to 30 carbon atoms such as benzene, toluene, xylene, mesitylene, ethylbenzene, biphenyl, diphenylmethane, diphenylethane, naphthalene or anthracene. a group in which n hydrogen atoms are removed from a hydrocarbon; and the n-valent group having a hetero ring, for example, an n-valent group from which n hydrogen atoms are removed from a hetero ring, a structure including a chain structure or an alicyclic hydrocarbon, and a heterocyclic ring The n-valent group of the structure and the like.

In terms of the reactivity with the carboxyl group of the polymer (A), X ¹ is preferably an n-valent aromatic hydrocarbon group having 5 to 30 carbon atoms or an n-valent group having a heterocyclic ring. , of formula (b-1) in the group ^{"* -NR 1 -CO-X 2} ( wherein, * represents a bond to X is ^1)" is preferably bonded to an aromatic ring or a heterocyclic ring. The aromatic ring is particularly preferably a benzene ring.

In terms of improving the reactivity with the carboxyl group of the polymer (A), X ¹ is preferably an n-valent organic group having an aromatic ring, that is, X ¹¹ , and more specifically, a carbon number of 5 to 30. An n-valent aromatic hydrocarbon group or an n-valent group having an aromatic heterocyclic ring. X ¹¹ is a carbon number of 30 or less, preferably a carbon number of 3 to 20, and more preferably a carbon number of 3 to 15.

The n-valent aromatic hydrocarbon group having 5 to 30 carbon atoms in X ¹ and X ¹¹ is preferably an n-valent group from which n hydrogen atoms are removed from a ring portion of an aromatic hydrocarbon having 5 to 30 carbon atoms. In this case, a group in which n hydrogen atoms are removed from the same ring may be used, or a group in which n hydrogen atoms are removed from a plurality of rings in total may be used.

Further, among the n-valent groups having an aromatic hetero ring in X ¹ and X ¹¹ , the aromatic heterocyclic ring is preferably a nitrogen-containing aromatic heterocyclic ring having a nitrogen atom in the ring portion. Specific examples thereof include a pyridine ring, a pyrimidine ring, a pyrazine ring, a pyridazine ring, and a triazine ring, and more preferably a pyridine ring, a pyrimidine ring or a triazine ring. The number of the aromatic heterocyclic rings which X ¹ and X ¹¹ have is not particularly limited, and may be one or two or more. The n-valent group having an aromatic heterocyclic ring is preferably an n-valent group from which n hydrogen atoms are removed from the ring portion of the aromatic heterocyclic ring. Further, in this case, a group in which n hydrogen atoms are removed from the same hetero ring may be used, or a group in which n hydrogen atoms are removed from a plurality of heterocycles in total may be used.

n is preferably an integer of 2 to 4, more preferably 2 or 3, and particularly preferably 2 in terms of the aspect of crosslinking which is moderately produced and the ease of obtaining the polymer (A).

Examples of the monovalent organic group having 1 to 30 carbon atoms in X ² include a hydrocarbon group such as a chain hydrocarbon group, an alicyclic hydrocarbon group or an aromatic hydrocarbon group, or a carbon-carbon bond in the hydrocarbon group or a formula (b) a group in which a functional group such as -O-, -COO-, -CO-, -NHCO-, -S- or -NH- is introduced at a position adjacent to the carbonyl group in -1). Further, each of these groups may have a substituent such as a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom or an iodine atom) or an alkoxy group. Specific examples of the monovalent hydrocarbon group in X ² include, for example, the groups exemplified in the description of R ¹ and the like.

In view of the fact that the amount of "HX ² " which is generated by the regeneration of the isocyanate group by heating is reduced in the reaction system, X ² is preferably a carbon number of 1 to 6, more preferably a carbon number of 1 to 2. 4.

Examples of X ² include a group represented by the following formula (x2-1) to formula (x2-7), and the like.

[Chemical 5]

(In the formula (x2-1) to the formula (x2-7), R ² , R ⁵ , R ⁶ , R ⁷ and R ⁹ are each independently a monovalent hydrocarbon group; and R ³ and R ⁴ are each independently a monovalent hydrocarbon group; Or the group "-OR ¹⁰ " (wherein R ¹⁰ represents a monovalent hydrocarbon group); R ⁸ is a monovalent aromatic hydrocarbon group; m is an integer of 2 to 11; "*" represents a bond to a carbonyl group.

Specific examples of the monovalent hydrocarbon group of R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ include a group exemplified as the monovalent hydrocarbon group of R ¹ . R ² to R ¹⁰ are each preferably a carbon number of 1 to 30.

m is preferably an integer of from 3 to 8, more preferably an integer of from 4 to 6.

In the above group, X ² is preferably a group represented by the above formula (x2-1) in terms of a small influence of the detached X ² on the film properties. R ² X ² is preferably a monovalent hydrocarbon group having a carbon number of 1 to 30 carbon atoms and more preferably a monovalent hydrocarbon group having 1 to 30. The divalent chain hydrocarbon group of R ² preferably has a carbon number of 1 to 10, more preferably 1 to 1 in terms of reducing the residual amount in the reaction system of "HX ² " which is generated by regeneration of an isocyanate group. 6, particularly preferably 1 to 4, particularly preferably an alkyl group having 1 to 4 carbon atoms.

Preferable examples of X ² include a group represented by the following formula (x2-1-1) to formula (x2-7-1), and the like.

[Chemical 6]

(wherein "*" represents a bond to a carbonyl group.)

Specific examples of the compound (B) include, for example, the compounds represented by the following formulas (b-1-1) to (b-1-11). Further, the compound (B) may be used alone or in combination of two or more.

[化8]

The compounding ratio of the compound (B) is preferably 0.1 parts by weight to 50 parts by weight, and more preferably 0.5 parts by weight to 30 parts by weight based on 100 parts by weight of the total amount of the polymer component contained in the liquid crystal alignment agent. The part by weight is particularly preferably from 1 part by weight to 20 parts by weight.

Further, in the case of using the liquid crystal alignment agent of the present invention to form a film, X ² is dissociated from the compound (B) to form an isocyanate group due to heating (post-baking) at the time of film formation, and The regenerated isocyanate group reacts with a carboxyl group of the polymer (A) to form a crosslinked structure.

The content ratio of the blocked isocyanato group (-NR ¹ -CO-X ² ) in the liquid crystal alignment agent is preferably 0.01 equivalent to 1.0 based on 1 equivalent of the carboxyl group of the polymer (A) in the liquid crystal alignment agent. The ratio of the equivalent is more preferably a ratio of 0.1 equivalent to 1.0 equivalent.

The compounding ratio of the compound (B-1) is preferably 0.1 parts by weight to 50 parts by weight, and more preferably 0.5 parts by weight, based on 100 parts by weight of the total amount of the polymer component contained in the liquid crystal alignment agent. It is preferably 30 parts by weight, and particularly preferably 1 part by weight to 20 parts by weight.

<Other ingredients>

The liquid crystal alignment agent of the present invention may contain the polymer (A) and other components other than the compound (B) as needed. Examples of the other component include a polymer other than the polymer (A), a compound having at least one epoxy group in the molecule (hereinafter referred to as "epoxy group-containing compound"), a functional decane compound, and the like. .

[Other polymers]

The other polymers can be used to improve solution properties or electrical properties. Examples of the other polymer include polyorganosiloxane, polyester, polyamine, cellulose derivative, polyacetal, polystyrene derivative, and poly(styrene-phenylbutylene). Amine derivatives, poly(meth)acrylates, and the like.

In the case where other polymer is added to the liquid crystal alignment agent, the compounding ratio of the other polymer is preferably 50% by weight or less, more preferably 0.1% by weight to 40% by weight based on the total amount of the polymer in the composition. % is particularly preferably from 0.1% by weight to 30% by weight.

[epoxy group-containing compound]

The epoxy group-containing compound can be used to improve the adhesion or electrical properties of the liquid crystal alignment film to the surface of the substrate. Here, examples of the epoxy group-containing compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether. Neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, trimethylolpropane triglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl Ether, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N, N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N-diglycidyl-benzylamine, N,N-diglycidyl-aminomethyl As a preferred compound, cyclohexane, N,N-diglycidyl-cyclohexylamine or the like is used. In addition to the above, an epoxy group-containing polyorganosiloxane such as described in International Publication No. 2009/096598 may be used as an example of the epoxy group-containing compound.

When the epoxy compound is added to the liquid crystal alignment agent, the compounding ratio of the epoxy compound is preferably 40 parts by weight or less, more preferably 100 parts by weight based on 100 parts by total of the polymer contained in the liquid crystal alignment agent. It is from 0.1 part by weight to 30 parts by weight.

[functional decane compound]

The functional decane compound can be used for the purpose of improving the printability of the liquid crystal alignment agent. use. Examples of such a functional decane compound include 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, and 2-aminopropyl group. Triethoxy decane, N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxy Baseline, 3-ureidopropyltrimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-triethoxy矽alkylpropyltriethylamine, 10-trimethoxydecyl-1,4,7-triazadecane, 9-trimethoxydecyl-3,6-diazepineacetic acid Ester, methyl 9-trimethoxydecyl-3,6-diazadecanoate, N-benzyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltrimethyl Oxaloxane, glycidoxymethyltrimethoxydecane, 2-glycidoxyethyltrimethoxydecane, 3-glycidoxypropyltrimethoxydecane, and the like.

In the case where the functional decane compound is added to the liquid crystal alignment agent, the compounding ratio of the functional decane compound is preferably 2 parts by weight or less, more preferably 0.02 parts by weight, based on 100 parts by total of the total of the polymer. 0.2 parts by weight.

Further, in addition to the compound, a compound having at least one oxetanyl group in the molecule, an antioxidant or the like may be used as the other component.

[solvent]

The liquid crystal alignment agent of the present invention is preferably prepared by dispersing or dissolving the polymer (A), the blocked isocyanate compound (B) as an additive component, and other components as necessary, in a suitable organic solvent. Composition.

Examples of the organic solvent to be used include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butylidene, N,N-dimethylformamide, and N,N-dimethyl B. Indoleamine, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene Alcohol methyl ether, ethylene glycol ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol - n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethyl Glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, Ethylene carbonate, propylene carbonate, and the like. These solvents may be used singly or in combination of two or more.

The solid content concentration in the liquid crystal alignment agent of the present invention (the ratio of the total weight of the components other than the solvent of the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, and the like, and is preferably selected. It is in the range of 1% by weight to 10% by weight. In other words, the liquid crystal alignment agent of the present invention is applied to the surface of the substrate in the form described later, and is preferably heated to form a coating film as a liquid crystal alignment film or a coating film to be a liquid crystal alignment film. At this time, when the solid content concentration is less than 1% by weight, the film thickness of the coating film is too small, and it is difficult to obtain a favorable liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, the film thickness of the coating film becomes too large, and it is difficult to obtain a favorable liquid crystal alignment film, and the viscosity of the liquid crystal alignment agent increases, and the coating property is lowered. tendency.

The range of the particularly preferable solid content concentration differs depending on the method used when the liquid crystal alignment agent is applied onto the substrate. For example, in the case of the rotator method, the solid content concentration (the ratio of the total weight of all the components other than the solvent in the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent) is particularly preferably 1.5% by weight to 4.5% by weight. The scope. In the case of using the printing method, it is particularly preferable to set the solid content concentration to a range of 3% by weight to 9% by weight, thereby setting the solution viscosity to 12 mPa. s~50mPa. The scope of s. In the case of using the inkjet method, it is particularly preferable to set the solid content concentration to a range of 1% by weight to 5% by weight, thereby setting the solution viscosity to 3 mPa. s~15mPa. The scope of s. The temperature at which the liquid crystal alignment agent of the present invention is prepared is preferably 10 ° C ~50 ° C, more preferably 20 ° C ~ 30 ° C.

<Liquid alignment film and liquid crystal display element>

The liquid crystal alignment film of the present invention is formed by using a liquid crystal alignment agent prepared in the above manner. Further, the liquid crystal display element of the present invention comprises a liquid crystal alignment film formed using the liquid crystal alignment agent. The driving mode of the liquid crystal display element is not particularly limited, and can be applied to various driving modes such as TN type, STN type, IPS type, FFS type, VA type, MVA type, and Polymer Sustained Alignment (PSA) type.

The liquid crystal display element of the present invention can be produced, for example, by a method including the following steps (1) to (3). Step (1) uses different substrates depending on the desired driving mode. Step (2) and step (3) are common to each drive mode.

[Step (1): Formation of coating film]

First, the liquid crystal alignment agent of the present invention is applied onto a substrate, and then the coated surface is heated to form a coating film on the substrate.

(1-1) In the case of manufacturing a TN type, STN type, VA type, MVA type or PSA type liquid crystal display element, two substrates provided with a patterned transparent conductive film are used as a pair, in each substrate The surface of the transparent conductive film is preferably coated with the liquid crystal alignment agent of the present invention by an offset printing method, a spin coating method, a roll coater method or an inkjet printing method. Here, as the substrate, for example, glass such as float glass or soda glass may be used; and polyethylene terephthalate, polybutylene terephthalate, polyether oxime, polycarbonate, poly(alicyclic olefin) may be used. ) A transparent substrate such as plastic. The transparent conductive film disposed on one side of the substrate may use a NESA film containing tin oxide (SnO ₂ ) (registered trademark of PPE), and contains indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ). Indium tin oxide (ITO) film or the like. In order to obtain a patterned transparent conductive film, for example, a method of forming a pattern by light or etching after forming a transparent conductive film without a pattern, a method of using a mask having a desired pattern when forming a transparent conductive film, or the like can be used. When the liquid crystal alignment agent is applied, in order to improve the adhesion between the surface of the substrate and the transparent conductive film and the coating film, the surface on which the coating film is formed on the surface of the substrate may be coated with a functional decane compound or a functional titanium compound. Pre-processing.

After the liquid crystal alignment agent is applied, it is preferable to perform preheating (prebaking) for the purpose of preventing sag of the applied alignment agent. The prebaking temperature is preferably from 30 ° C to 200 ° C, more preferably from 40 ° C to 150 ° C, and particularly preferably from 40 ° C to 100 ° C. The prebaking time is preferably from 0.25 minutes to 10 minutes, more preferably from 0.5 minutes to 5 minutes. Then, for the purpose of completely removing the solvent, a calcination (post-baking) step is additionally carried out for the purpose of thermally imidating the proline structure present in the polymer as needed. The calcination temperature (post-baking temperature) at this time is preferably 80 ° C to 300 ° C, and more preferably 120 ° C to 250 ° C. The post-baking time is preferably from 5 minutes to 200 minutes, more preferably from 10 minutes to 100 minutes. The film thickness of the film formed as described above is preferably 0.001 μm to 1 μm, and more preferably 0.005 μm to 0.5 μm.

(1-2) In the case of manufacturing an IPS type or FFS type liquid crystal display element, an electrode forming surface is provided on a substrate provided with an electrode including a transparent conductive film or a metal film patterned into a comb shape, and is not provided The liquid crystal alignment agent of the present invention is applied to one surface of the opposite substrate of the electrode, and then each coated surface is heated to form a coating film. The material of the substrate and the transparent conductive film used at this time, the coating method, the heating conditions after coating, the patterning method of the transparent conductive film or the metal film, the pretreatment of the substrate, and the preferred film thickness of the formed coating film , the same as the above (1-1). As the metal film, for example, a film containing a metal such as chromium can be used.

In any of the above (1-1) and (1-2), the coating film to be an alignment film is formed by applying a liquid crystal alignment agent onto the substrate and then removing the organic solvent. At this time, the polymer contained in the liquid crystal alignment agent of the present invention is polyamic acid or polyglycolate, or In the case of a ruthenium iodide polymer having a ruthenium ring structure and a valine structure, the dehydration ring-closure reaction may be carried out by further heating after the formation of the coating film to form a more imidized coating film.

[Step (2): Friction treatment]

In the case of manufacturing a TN type, STN type, IPS type or FFS type liquid crystal display element, the following rubbing treatment is carried out: the step is carried out by using a roll wound with a cloth such as nylon, rayon, cotton or the like (for example) The coating film formed in 1) is rubbed in a fixed direction. Thereby, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film. On the other hand, in the case of manufacturing a VA liquid crystal display element, the coating film formed in the above step (1) can be directly used as a liquid crystal alignment film, and the coating film can be subjected to a rubbing treatment. Further, the liquid crystal alignment film after the rubbing treatment may be further subjected to a treatment of changing a pretilt angle of a partial region of the liquid crystal alignment film by irradiating a part of the liquid crystal alignment film with ultraviolet rays, or forming a resistance on a part of the surface of the liquid crystal alignment film. After the etchant film, the rubbing treatment is performed in a direction different from the previous rubbing treatment, and then the treatment of the resist film is removed; thus, the liquid crystal alignment film has different liquid crystal alignment capabilities in each region. In this case, the visual field characteristics of the obtained liquid crystal display element can be improved.

In the case of manufacturing a PSA type liquid crystal display element, the following step (3) may be carried out by directly using the coating film formed in the above step (1), or may be carried out by a simple method for controlling collapse of liquid crystal molecules. A weak rubbing treatment is performed for the purpose of the method of the splitting.

[Step (3): Construction of liquid crystal cell]

(3-1) A liquid crystal cell is manufactured by preparing two substrates in which a liquid crystal alignment film is formed as described above, and disposing liquid crystal between two substrates arranged in the opposite direction. For the production of the liquid crystal cell, for example, the following two methods are exemplified. First, the first method is a previously known method. In this method, first, the two substrates are opposed to each other via a gap (cell gap) so that the respective liquid crystal alignment films face each other, and the peripheral portions of the two substrates are bonded together using a sealant, and the surface of the substrate and the sealant are drawn. After filling the liquid crystal into the cell gap, the injection hole is sealed, whereby the liquid crystal cell can be manufactured. In addition, the second method is a method called a One Drop Fill (ODF) method. In this method, a predetermined portion on one of the two substrates on which the liquid crystal alignment film is formed is applied with, for example, an ultraviolet curable sealant, and further added to a predetermined number of portions on the liquid crystal alignment film surface. After the liquid crystal, another substrate is bonded in such a manner that the liquid crystal alignment film faces each other. Then, the liquid crystal is spread over the entire surface of the substrate, and then the entire surface of the substrate is irradiated with ultraviolet light to harden the sealant, thereby manufacturing a liquid crystal cell. In the case of using any of the methods, it is preferred to remove the liquid crystal cell by heating the liquid crystal cell produced in the above manner to a temperature at which the liquid crystal used becomes an isotropic phase, and then slowly cooling to room temperature. The flow alignment at the time.

As the sealant, for example, an epoxy resin containing a hardener and an alumina ball as a spacer can be used. Further, examples of the liquid crystal include nematic liquid crystals and smectic liquid crystals. Among them, nematic liquid crystals are preferable, and for example, Schiff base liquid crystals and oxidized couples can be used. Azoxy liquid crystal, biphenyl liquid crystal, phenylcyclohexane liquid crystal, ester liquid crystal, terphenyl liquid crystal, biphenyl cyclohexane liquid crystal, pyrimidine liquid crystal, dioxane liquid crystal, bicyclooctane A liquid crystal, a cubane liquid crystal, or the like. Further, it is also possible to use a liquid crystal (cholesteric liquid crystal) such as cholesteryl chloride, cholesteryl nonanoate, or cholesteryl carbonate. a chiral agent sold under the trade names "C-15", "CB-15" (manufactured by Merck); p-methoxybenzylidene-p-amino-2-methylbutyl A ferroelectric liquid crystal such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate.

(3-2) In the case of producing a PSA type liquid crystal display device, a liquid crystal cell is constructed in the same manner as in the above (3-1) except that the photopolymerizable compound is injected or dropped together with the liquid crystal. Then, the liquid crystal cell is irradiated with light in a state where a voltage is applied between the conductive films of the pair of substrates. The voltage applied here can be, for example, a direct current voltage of 5 V to 50 V or an alternating current voltage. Further, as the light to be irradiated, for example, ultraviolet light and visible light including light having a wavelength of 150 nm to 800 nm can be used, and ultraviolet light containing light having a wavelength of 300 nm to 400 nm is preferable. As the light source for illuminating light, for example, a low pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser or the like can be used. Further, the ultraviolet light of the preferred wavelength region can be obtained by a method in which a light source is used in combination with, for example, a filter, a diffraction grating, or the like. The irradiation amount of light is preferably 1,000 J/m ² or more and less than 200,000 J/m ² , and more preferably 1,000 J/m ² to 100,000 J/m ² .

Then, the liquid crystal display element of the present invention can be obtained by laminating a polarizing plate on the outer surface of the liquid crystal cell. The polarizing plate to be bonded to the outer surface of the liquid crystal cell may be a polarizing plate in which a polarizing film called "H film" is sandwiched by a cellulose acetate protective film or a polarizing plate including the H film itself. The H film is a polarizing film obtained by absorbing iodine while extending the polyvinyl alcohol to the side. Further, in the case where the coating film is subjected to the rubbing treatment, the two substrates are arranged at a predetermined angle with each other in the rubbing direction of each of the coating films, for example, orthogonally or anti-parallel.

The liquid crystal display element of the present invention can be effectively applied to various devices, for example, can be used for: a clock, a portable game console, a word processor, a note type personal computer, a car navigation system. (car navigation system), camcorder, personal digital assistant (PDA), digital camera, mobile phone, smart phone, various monitors, LCD TVs and other display devices.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples.

In the following examples and comparative examples, the oxime imidization ratio of the polyimine in the polymer solution, the solution viscosity of the polymer solution, the weight average molecular weight of the polymer, and the epoxy equivalent were measured by the following methods.

[醯Iminization rate of polyimine]

The solution of the polyimine is put into pure water, and the obtained precipitate is sufficiently dried under reduced pressure at room temperature, and then dissolved in deuterated dimethyl hydrazine, using tetramethyl decane as a reference substance at room temperature. ¹ H- NMR measurement ^{(1 H-Nuclear magnetic resonance,} 1 H-NMR). From the obtained ¹ H-NMR spectrum, the oxime imidization ratio [%] was determined by the following formula (1).

醯imination rate [%]=(1-A ¹ /A ² ×α)×100...(1)

(In the formula (1), A ¹ is the peak area of the proton derived from the NH group appearing near the chemical shift of 10 ppm, A ² is the peak area derived from other protons, and α is the precursor of the other proton relative to the polymer The ratio of the number of protons of the NH group in (polyglycine).)

[Solid viscosity of polymer solution]

Using a prescribed solvent, for a solution prepared to have a polymer concentration of 10% by weight, the solution viscosity of the polymer solution was measured at 25 ° C using an E-type rotational viscometer [mPa. s].

[weight average molecular weight of polymer]

The weight average molecular weight is a polystyrene equivalent value measured by gel permeation chromatography under the following conditions.

Pipe column: manufactured by Tosoh (stock), TSKgelGRCXLII (trade name)

Solvent: tetrahydrofuran

Temperature: 40 ° C

Pressure: 68kgf/cm ²

[epoxy equivalent]

The epoxy equivalent was measured by the hydrochloric acid-methyl ethyl ketone method described in Japanese Industrial Standard C 2105 (JIS C 2105).

<Synthesis of Polymer (A)>

[Synthesis Example 1: Synthesis of Polyimine (PI-1)]

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 8.6 g (0.08 mol) of p-phenylenediamine as diamine, and 3,5- 10.5 g (0.02 mol) of cholesteryl diaminobenzoate, dissolved in 166 g of N-methyl-2-pyrrolidone (NMP), and reacted at 60 ° C for 6 hours to obtain polyglycine 20 % by weight solution. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the obtained solution viscosity was 90 mPa. s.

Then, NMP was added to the obtained polyaminic acid solution to prepare a solution having a polyglycine concentration of 7 wt%, and 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system is subjected to solvent replacement by a new NMP (by this operation, the pyridine and acetic anhydride used in the dehydration ring-closure reaction are removed to the outside of the system; the same applies hereinafter), thereby obtaining a ruthenium-containing imidization. A solution of about 26% polyethylenimine (PI-1) 26% by weight. A small amount of the obtained polyimine solution was added, and NMP was added to prepare a solution having a polyimine concentration of 10% by weight, and the obtained solution viscosity was 45 mPa. s.

[Synthesis Example 2: Synthesis of Polyimine (PI-2)]

22.5 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 10.7 g (0.07 mol) of 3,5-diaminobenzoic acid as diamine Cholesteryloxy-2,4-diamine 7.35 g (0.015 mol) of a base benzene and 6.94 g (0.015 mol) of the compound represented by the formula (D-1-5) were dissolved in 190 g of NMP, and reacted at 60 ° C for 6 hours to obtain a content. A 20% by weight solution of polyamidamine. A small amount of the obtained polyamic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the obtained solution viscosity was 80 mPa. s.

Then, NMP was added to the obtained polyaminic acid solution to prepare a solution having a polyglycine concentration of 7 wt%, and 15.7 g of pyridine and 20.3 g of acetic anhydride were added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was subjected to solvent replacement using a new NMP, thereby obtaining a solution containing 26% by weight of polyimine (PI-2) having a ruthenium iodide ratio of about 80%. A small amount of the obtained polyimine solution was added, and NMP was added to prepare a solution having a polyimine concentration of 10% by weight, and the obtained solution viscosity was 40 mPa. s.

[Synthesis Example 3: Synthesis of Polyimine (PI-3)]

2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride as tetracarboxylic dianhydride 18.7 g (0.075 mol) and 1,2,3 4-cyclobutane tetracarboxylic dianhydride 4.90 g (0.025 mol), 3,5-diaminobenzoic acid as diamine 10.7 g (0.07 mol) and 1,3-diamino-4- {4-[trans-4-(trans-4-n-pentylcyclohexyl)cyclohexyl]phenoxy}benzene (the compound represented by the formula (D-1-2)) 13.1 g (0.03 Mo The ear was dissolved in 190 g of NMP, and reacted at 60 ° C for 6 hours to obtain a solution containing 20% by weight of polyglycine. A small amount of the obtained poly-proline solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the viscosity of the solution was determined to be 85 mPa. s.

Then, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyglycine concentration of 7 wt%, and 9.5 g of pyridine and 12.3 g of acetic anhydride were added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was subjected to solvent replacement using a new NMP, whereby a solution containing 26% by weight of polyamidolimine (PI-3) having a ruthenium iodide ratio of about 65% was obtained. A small amount of the obtained polyimine solution was added, and NMP was added to prepare a polyimine concentration of 10% by weight. % solution, the measured solution viscosity is 45mPa. s.

[Synthesis Example 4: Synthesis of Polyimine (PI-4)]

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5 -(tetrahydro-2,5-dioxo-3-furanyl)naphtho[1,2-c]furan-1,3-dione 160g (0.50 mol), p-phenylenediamine as diamine 91 g (0.85 mol), 1,3-bis(3-aminopropyl)tetramethyldioxane 25 g (0.10 mol) and 3,6-bis(4-aminobenzimidyloxy) Cholesterane 25 g (0.040 mol), and 1.4 g (0.015 mol) of aniline as a monoamine, dissolved in 960 g of NMP, and reacted at 60 ° C for 6 hours, thereby obtaining a polyglycine-containing Solution. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the obtained solution viscosity was 60 mPa. s.

Then, 2,700 g of NMP was added to the obtained polyamic acid solution, and 390 g of pyridine and 410 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring-closure reaction, the solvent in the system is subjected to solvent replacement using a new γ-butyrolactone, thereby obtaining a solution containing 15% by weight of polyimine (PI-4) having a ruthenium iodide ratio of about 95%. About 2,500g. A small amount of this solution was added, and NMP was added to prepare a solution having a concentration of 10% by weight of polyimine. The viscosity of the solution was determined to be 70 mPa. s.

[Synthesis Example 5: Synthesis of Polyimine (PI-5)]

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 8.6 g (0.08 mol), 4,4' of p-phenylenediamine as a diamine. -diaminodiphenylmethane 2.0 g (0.01 mol) and 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl 3.2 g (0.01 mol), dissolved in 324 g In the NMP, the reaction was carried out at 60 ° C for 4 hours to obtain a solution containing 10% by weight of polyglycine.

Then, 360 g of NMP was added to the obtained polyamic acid solution, and 39.5 g of pyridine and 30.6 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, The solvent in the system was subjected to solvent replacement using a new NMP to obtain a solution containing 10% by weight of polyimine (PI-5) having a ruthenium iodide ratio of about 93%. A small amount of the obtained polyimine solution was obtained, and the viscosity of the solution was determined to be 30 mPa. s.

[Synthesis Example 6: Synthesis of Polyimine (PI-6)]

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 12.2 g (0.08 mol) of 3,5-diaminobenzoic acid as diamine And 9.80 g (0.02 mol) of cholestyloxy-2,4-diaminobenzene, dissolved in 178 g of NMP, and reacted at 60 ° C for 6 hours to obtain 20% by weight of polyglycine. Solution. A small amount of the obtained polyamic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the obtained solution viscosity was 80 mPa. s.

Then, NMP was added to the obtained polyaminic acid solution to prepare a solution having a polyglycine concentration of 7 wt%, and 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was subjected to solvent replacement using a new NMP, thereby obtaining a solution containing 26% by weight of polyimine (PI-6) having a ruthenium iodide ratio of about 65%. A small amount of the obtained polyimine solution was added, and NMP was added to prepare a solution having a polyimine concentration of 10% by weight, and the obtained solution viscosity was 40 mPa. s.

[Synthesis Example 7: Synthesis of polyorganosiloxane (APS-1)]

In a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, and a reflux cooling tube, 100.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, 500 g of methyl isobutyl ketone, and three to three were charged. The base amine was 10.0 g and mixed at room temperature. Then, 100 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and the reaction was carried out at 80 ° C for 6 hours while stirring under reflux. After completion of the reaction, the organic layer was taken out and washed with a 0.2% by weight aqueous solution of ammonium nitrate until the water after washing became neutral, and then the solvent and water were distilled off under reduced pressure to obtain a viscous transparent liquid. Epoxy-based polyorganosiloxane (EPS-1). ¹ H-NMR analysis of the epoxy group-containing polyorganosiloxane (EPS-1) gave a peak based on the theoretical strength, and the epoxy group-based peak was obtained in the vicinity of the chemical shift (δ) = 3.2 ppm. A side reaction in which no epoxy group is produced. The obtained epoxy group-containing polyorganosiloxane had a weight average molecular weight Mw of 3,500 and an epoxy equivalent of 180 g/mole.

Then, 10.0 g of an epoxy group-containing polyorganosiloxane (EPS-1), 30.28 g of methyl isobutyl ketone as a solvent, and 4-dodecyloxybenzoic acid were placed in a 200 mL three-necked flask. 3.98 g and 0.10 g of UCAT 18X (trade name, manufactured by San-Apro Co., Ltd.) as a catalyst were reacted at 100 ° C for 48 hours while stirring. After completion of the reaction, the solution obtained by adding ethyl acetate to the reaction mixture was washed with water three times, and the organic layer was dried over magnesium sulfate, and the solvent was distilled off to obtain a liquid crystal-aligned polyorganosiloxane (APS-1). 9.0g. The weight average molecular weight Mw of the obtained polymer was 9,900.

<Example 1>

[Preparation of Liquid Crystal Aligning Agent]

In a solution containing polyimine (PI-1) as the polymer (A), 5 parts by weight of the compound represented by the formula (b-1-1) is added to 100 parts by weight of the polymer. The NMP solution was used as a blocked isocyanate compound (B) to prepare a solution having a solution composition of NMP:BC (butyl cellosolve) = 50:50 (weight ratio) and a solid concentration of 6.0% by weight. This solution was filtered using a filter having a pore size of 1 μm, thereby preparing a liquid crystal alignment agent (S1).

[Manufacture of liquid crystal cell]

The prepared liquid crystal alignment agent (S1) was applied onto a transparent electrode surface of a glass substrate with a transparent electrode containing an ITO film at a temperature of 80 ° C using a liquid crystal alignment film printer (manufactured by Japan Photo Printing Co., Ltd.). The hot plate was preheated (prebaked) for 1 minute to remove the solvent, and then heated (post-baked) on a hot plate at 210 ° C for 30 minutes to form a coating film having an average film thickness of 80 nm.

For the coating film, a friction machine having a roller wound with a rayon cloth was used, and the roller rotation speed was 500. The rpm, the platform moving speed of 3 cm/sec, and the hair pressing length of 0.4 mm were subjected to rubbing treatment to impart liquid crystal alignment energy. Then, ultrasonic cleaning was performed for 1 minute in ultrapure water, followed by drying in a 100 ° C clean oven for 10 minutes, thereby obtaining a substrate having a liquid crystal alignment film. This operation was repeated to obtain a pair of (two pieces) substrates having a liquid crystal alignment film.

Next, an epoxy resin adhesive having an alumina ball having a diameter of 5.5 μm is applied to the outer edges of the pair of substrates on the surface of the liquid crystal alignment film, and then the liquid crystal alignment film faces are opposed to each other. Crimp to harden the adhesive. Then, a nematic liquid crystal (manufactured by Merck & Co., MLC-6221 (trade name)) is filled between the pair of substrates from the liquid crystal injection port, and then the liquid crystal injection port is sealed with an acrylic photocurable adhesive to produce a liquid crystal. unit.

[Evaluation of Reliability of Liquid Crystal Alignment Film]

With respect to the obtained liquid crystal cell, after applying a voltage of 5 V with an application time of 60 microseconds and a span of 167 milliseconds, the voltage holding ratio (VHR1) after 167 milliseconds from the application release was measured. Then, the liquid crystal cell was allowed to stand in an 80 ° C oven irradiated with a light-emitting diode (LED) lamp for 200 hours, and then allowed to stand at room temperature to be naturally cooled to room temperature. After cooling, a voltage of 5 V was applied to the liquid crystal cell at a time of application of 60 microseconds and a span of 167 milliseconds, and then the voltage holding ratio (VHR2) after 167 milliseconds from the release of the application was measured. Further, the measuring device used "VHR-1" (trade name) manufactured by Toyo Technica Co., Ltd. The rate of change (ΔVHR) of the voltage holding ratio (VHR) at this time was calculated by the following formula (2), and the reliability of the liquid crystal alignment film was evaluated based on ΔVHR.

△VHR[%]=(VHR1-VHR2)/(VHR1)×100...(2)

The evaluation was carried out in such a manner that the case where ΔVHR was 0% or more and less than 0.4% was evaluated as "especially good (?)", and the case where 0.4% or more and less than 1.5% was evaluated as reliability. "Good (○)", the case of 1.5% or more and 2.0% or less was evaluated as the reliability "may (?)", and the case of more than 2.0% was evaluated as the reliability "poor (x)". As a result, ΔVHR of the liquid crystal cell was 0.5 [%], and the reliability was good.

<Example 2 to Example 9 and Comparative Example 1>

A liquid crystal alignment agent (S2) to a liquid crystal alignment agent (S9) and a liquid crystal were prepared in the same manner as in Example 1 except that the type and amount of the polymer component and the additive component to be used were changed as described in Table 1 below. Orienting agent (R1). Further, in the same manner as in the above-described Example 1, the reliability of the liquid crystal cell was evaluated for each of the prepared liquid crystal alignment agents. These results are shown in Table 1 below.

In Table 1, the "amount" of the polymer component column indicates each compounding ratio (parts by weight) based on 100 parts by weight of the total amount of the polymer component contained in the liquid crystal alignment agent. In addition, the "addition amount" of the additive column means a compounding ratio (parts by weight) based on 100 parts by weight of the total amount of the polymer component in the liquid crystal alignment agent. The abbreviations of the additives in Table 1 are respectively the following meanings.

Add-1: the compound represented by the formula (b-1-1)

Add-2: the compound represented by the formula (b-1-2)

Add-3: a compound represented by the following formula (m-1)

As shown in Table 1, in Examples 1 to 9, the ΔVHR was as small as less than 1.0%, and the reliability of the liquid crystal display element was "good". On the other hand, in Comparative Example 1, ΔVHR was as large as 2.9%, and the reliability was "poor".

<Example 10 to Example 13 and Comparative Example 2>

A liquid crystal alignment agent (S10) to a liquid crystal alignment agent (S13) and a liquid crystal were prepared in the same manner as in Example 1 except that the type and amount of the polymer component and the additive component to be used were changed as described in Table 2 below. Orienting agent (R2). Further, in the same manner as in the above-described Example 1, the reliability of the liquid crystal cell was evaluated for each of the prepared liquid crystal alignment agents. These results are shown in Table 2 below.

In Table 2, the "amount" of the polymer component column and the "addition amount" of the additive column are indicated. The values are the same as in Table 1. The abbreviations of the additives in Table 2 are respectively the following meanings.

Add-4: the compound represented by the formula (b-1-9)

Add-5: the compound represented by the formula (b-1-10)

Add-6: a compound represented by the following formula (m-2)

Add-7: the compound represented by the formula (b-1-11)

As shown in Table 2, in Examples 10 to 12, ΔVHR was as small as 0.2% or less, and the reliability of the liquid crystal display element was evaluated as "particularly good". Further, in Example 13, ΔVHR was 1.8%, which was an evaluation of the reliability "may". On the other hand, in Comparative Example 2, ΔVHR was as large as 2.5%, and the reliability was "poor".

Claims (13)

A liquid crystal alignment agent comprising: at least one polymer (A) selected from the group consisting of polylysine, polyphthalate, and polyamidene; and polyfunctional intercalation having an aromatic ring Segment isocyanate compound (B-1). The liquid crystal alignment agent according to claim 1, wherein the blocked isocyanate compound (B-1) is a compound represented by the following formula (b1-1). (In the formula (b1-1), R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms; X ¹¹ is an n-valent organic group having an aromatic ring; and X ² is a monovalent organic group having 1 to 30 carbon atoms. n is an integer from 2 to 6; wherein a plurality of R ¹ in the formula may be the same or different, and a plurality of X ² may be the same or different). The liquid crystal alignment agent according to claim 2, wherein the X ¹¹ is an n-valent aromatic hydrocarbon group having 5 to 30 carbon atoms or an n-valent group having an aromatic hetero ring. The liquid crystal alignment agent according to claim 2, wherein the X ¹¹ is an n-valent group from which n hydrogen atoms are removed from a ring portion of an aromatic hydrocarbon having 5 to 30 carbon atoms. The liquid crystal alignment agent according to Item 2 or 3, wherein the X ¹¹ is an n-valent organic group having an aromatic hetero ring. The liquid crystal alignment agent according to claim 5, wherein the X ¹¹ is an n-valent group from which n hydrogen atoms are removed from a ring portion of the aromatic heterocyclic ring. The liquid crystal alignment agent according to Item 2 or 3, wherein the X ² is a group "*-OR ² " (wherein R ² is a monovalent hydrocarbon group having 1 to 30 carbon atoms, "* "Expresss a bond to a carbonyl group." The liquid crystal alignment agent according to claim 7, wherein the R ² is a monovalent chain hydrocarbon group having 1 to 30 carbon atoms. The liquid crystal alignment agent according to claim 2, wherein the X ¹¹ is an n-valent organic group having a carbon number of 3 to 15 having an aromatic ring. The liquid crystal alignment agent according to any one of claims 1 to 3, wherein the blocked isocyanate compound is 100 parts by weight based on the total amount of the polymer component contained in the liquid crystal alignment agent. The content of (B-1) is from 0.1 part by weight to 50 parts by weight. The liquid crystal alignment agent according to any one of claims 1 to 3, wherein at least at least one of a polyamic acid obtained by reacting a tetracarboxylic dianhydride with a diamine and a polyimine is contained. As the polymer (A), the tetracarboxylic dianhydride comprises a solvent selected from 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 2,4,6,8-tetracarboxybicyclo[3.3.0 Octane-2:4,6:8-dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride and 1 At least one of the group consisting of 2,3,4-cyclopentanetetracarboxylic dianhydride. A liquid crystal alignment film which is formed using the liquid crystal alignment agent according to any one of the first to eleventh aspects of the invention. A liquid crystal display element comprising the liquid crystal alignment film according to claim 12 of the patent application.