TWI621662B - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

The present invention provides a liquid crystal alignment agent that not only has good coatability on a substrate, but also makes it difficult to swell a printing plate and has good continuous printability. The liquid crystal alignment agent of the present invention includes: at least one polymer (A) selected from the group consisting of polyamidic acid, polyamidoimide, polyamidate, and polyorganosiloxane; and a formula including the following formula The solvent of the compound (p1) represented by (1).

(In the formula (1), R ¹ and R ³ are each independently a linear or branched monovalent hydrocarbon group having 1 to 3 carbon atoms, and R ² is a linear or branched carbon number 2 to 5 Alkanediyl.)

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. In particular, the present invention relates to a liquid crystal alignment agent with good printability, and a liquid crystal alignment film and a liquid crystal display element manufactured using the liquid crystal alignment agent. .

In the past, liquid crystal display elements have been developed with various driving methods, such as electrode structure or physical properties of liquid crystal molecules used. For example, Twisted Nematic (TN) or Super Twisted Nematic (Super) Twisted Nematic (STN) type, Vertical Alignment (VA) type, In Plane Switching (IPS) type, Fringe Field Switching (FFS) type, Optically Compensated Bend (OCB) ) Type and other liquid crystal display elements. These liquid crystal display elements have a liquid crystal alignment film for aligning liquid crystal molecules. In terms of various characteristics such as heat resistance, mechanical strength, and affinity with liquid crystals, the materials of the liquid crystal alignment film include polyamic acid, polyimide, and polyorganosiloxane.

In the liquid crystal alignment agent, the polymer component is dissolved in a solvent. A crystal alignment agent is coated on the substrate and heated to form a liquid crystal alignment film. Here, in order to uniformly dissolve the polymer, the solvent of the liquid crystal alignment agent is usually an aprotic polar solvent such as N-methyl-2-pyrrolidone or γ-butyrolactone. In addition, in order to improve the coatability (printability) of the liquid crystal alignment agent when the liquid crystal alignment agent is coated on a substrate, an organic solvent having a relatively low surface tension such as butyl cellosolve is used in combination with the organic solvent ( (For example, refer to patent document 1 or patent document 2).

A method of applying the liquid crystal alignment agent to the substrate is a variety of methods such as a spin coating method, a lithographic method, and an inkjet method. Of these methods, the lithographic printing method is generally performed using a transfer printing device that applies a liquid crystal alignment agent to a printing plate containing a resin such as APR (registered trademark), and uses the printing plate to align the liquid crystal. The agent is transferred onto a substrate (for example, refer to Patent Document 3).

[Prior technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2010-97188

[Patent Document 2] Japanese Patent Laid-Open No. 2010-156934

[Patent Document 3] Japanese Patent Laid-Open No. 2001-343649

However, the butyl cellosolve, which is generally used in order to improve the coatability of the liquid crystal alignment agent, tends to swell the APR resin. Therefore, when a liquid crystal alignment agent containing a butyl cellosolvent is applied to a substrate by lithography, the liquid crystal alignment agent is applied to the printing plate repeatedly, and the printing plate may swell, and there is a concern that the printability may decrease. In addition, the solvent component of the liquid crystal alignment agent requires that it is difficult to precipitate a polymer on a printer even when printing is performed continuously, and printability (continuous printability) is required. good. In view of the above background, in order to improve the printability of the liquid crystal alignment agent, it is required to find an organic solvent that not only has good coatability on the substrate, but also makes it difficult to swell the printing plate, and it is difficult to cause polymerization on the printing machine during continuous printing. Precipitation of organic solvents.

The present invention has been made in view of the above-mentioned problems, and a main object thereof is to provide a liquid crystal alignment agent that has good coatability on a substrate, and is difficult to swell a printing plate, and has good continuous printability.

The inventors of the present invention conducted intensive research in order to achieve the problems of the related art as described above, and found that the above problems can be solved by using a specific compound as at least a part of the solvent, thereby completing the present invention. Specifically, the present invention provides the following liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element.

In a technical solution of the present invention, a liquid crystal alignment agent is provided, which contains at least one polymer selected from the group consisting of polyamidic acid, polyamidoimide, polyamidate, and polyorganosiloxane. (A); and a solvent containing the compound (p1) represented by the following formula (1).

(In the formula (1), R ¹ and R ³ are each independently a linear or branched monovalent hydrocarbon group having 1 to 3 carbon atoms, and R ² is a linear or branched carbon number 2 to 5 Alkanediyl.)

By using the compound (p1) as at least a part of the solvent of the liquid crystal alignment agent, it is possible not only to impart good coatability to the liquid crystal alignment agent when printing on a substrate, but also to make it difficult for the APR plate to swell. In addition, even in the case where the liquid crystal alignment agent is continuously printed, it is difficult to cause precipitation of a polymer on a printer, and printability is good.

According to another aspect of the present invention, there is provided not only the compound (p1) but also a compound selected from the group consisting of 1,3-dimethyl-2-imidazolidinone, and the following formula (2), and At least one compound (p2) in the group consisting of the compound represented by the following formula (3) is used as a liquid crystal alignment agent as a solvent component.

(In formula (2), R ⁴ and R ⁵ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a monovalent group containing "-O-" between carbon-carbon bonds of the hydrocarbon group, R ⁴ and R ⁵ may be bonded to each other to form a ring structure; R ⁶ is an alkyl group having 1 to 6 carbon atoms.)

[Chemical 3]

(In formula (3), R ⁷ is a monovalent hydrocarbon group having 2 to 5 carbon atoms or a monovalent group containing "-O-" between carbon-carbon bonds in the hydrocarbon group.)

In addition, in one aspect of the present invention, a liquid crystal alignment film formed using the liquid crystal alignment agent and a liquid crystal display element including the liquid crystal alignment film are provided. Since the liquid crystal alignment film of the present invention is formed using the above-mentioned liquid crystal alignment agent, a uniform coating film can be formed and the film quality is good. In addition, when a liquid crystal display element is manufactured using such a liquid crystal alignment film, printing defects can be reduced during the manufacturing process, and as a result, the yield of a product can be improved.

The liquid crystal alignment agent of the present invention not only contains at least one polymer (A) selected from the group consisting of polyamidic acid, polyamidoimide, polyamidate, and polyorganosiloxane as a polymer component, The polymer (A) is dissolved in a solvent. The liquid crystal alignment agent will be described below.

<Polyamic acid>

The polyamidic acid of the present invention can be obtained by reacting a tetracarboxylic dianhydride with a diamine.

[Tetracarboxylic dianhydride]

Examples of the tetracarboxylic dianhydride used to synthesize the polyamic acid of the present invention include aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride. Specific examples of these tetracarboxylic dianhydrides include aliphatic tetracarboxylic dianhydrides, such as 1,2,3,4-butane tetracarboxylic dianhydride, and the like; and examples of alicyclic tetracarboxylic dianhydride. : 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (Tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro -8-methyl-5- (tetrahydro-2,5-dioxo-3-furyl) -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 -Furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2: 3,5: 6- Dianhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] Undecane-3,5,8,10-tetraketone, cyclohexanetetracarboxylic dianhydride, etc .; Examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride. In addition, Japan can be used. Patent Tetracarboxylic dianhydride described in Japanese Patent Publication No. 2010-97188. Moreover, the said tetracarboxylic dianhydride can be used individually by 1 type or in combination of 2 or more types.

From the viewpoints of transparency and solubility in a solvent, the tetracarboxylic dianhydride used for the synthesis preferably contains an alicyclic tetracarboxylic dianhydride. The alicyclic tetracarboxylic dianhydride preferably contains a compound selected from the group consisting of 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2-c] furan-1,3- Dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2- c] furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-dianhydride, and 1,2,3,4- At least one of the group consisting of cyclobutanetetracarboxylic dianhydride, particularly preferably, is selected from the group consisting of 2,3,5-tricarboxycyclopentylacetic dianhydride, 2,4,6,8-tetracarboxybicyclo [ 3.3.0] at least one of the group consisting of octane-2: 4,6: 8-dianhydride and 1,2,3,4-cyclobutanetetracarboxylic dianhydride.

In containing a compound selected from the group consisting of 2,3,5-tricarboxycyclopentylacetic dianhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-dianhydride, and In the case where at least one of the groups consisting of 1,2,3,4-cyclobutanetetracarboxylic dianhydride is used as the tetracarboxylic dianhydride, the tetracarboxylic dianhydride is used for synthesizing polyamic acid. The total content of these compounds is preferably 10 mol% or more, and more preferably 20 mol% to 100 mol%.

[Diamine]

Examples of the diamine used for synthesizing the polyamidic acid of the present invention include an aliphatic diamine, an alicyclic diamine, an aromatic diamine, and a diamine organosiloxane. As specific examples of these diamines, examples of the aliphatic diamine include metaxylylene diamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylene. Methyldiamine and the like; Examples of the alicyclic diamine include 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) Group) Cyclohexane and the like; Examples of the aromatic diamine include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 1,5 -Diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl, 2,7-diaminophosphonium, 4,4'-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis ( 4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '-(p-phenylene diisopropylidene) bisaniline, 4,4'-(m-phenylene diisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) ) Benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3 2,6-diaminoacridine, 3,6-diamino Carbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N, N'-bis (4-aminophenyl) -benzidine, N, N'-bis (4-aminophenyl) -N, N'-dimethylbenzidine, 1,4-bis- (4 -Aminophenyl) -piperazine, 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-5-amine, 1- (4 -Aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-indene-6-amine, 3,5-diaminobenzoic acid, cholesteryloxy-3 Cholestanyloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholesteryloxy-2 , 4-diaminobenzene, cholestyloxy-2,4-diaminobenzene, cholestanyl 3,5-diaminobenzoate, 3,5 -Cholestenyl 3,5-diaminobenzoate, lanostanyl 3,5-diaminobenzoate, 3,6-bis (4 -Aminobenzoyloxy) cholestane, 3,6-bis (4-aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 4- (4'- Trifluoromethoxybenzyloxy) cyclohexyl-3,5-diaminobenzyl Acid ester, 4- (4'-trifluoromethylbenzyloxy) cyclohexyl-3,5-diaminobenzoate, 1,1-bis (4-((aminophenyl) formyl) Phenyl) -4-butylcyclohexane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4-heptylcyclohexane, 1,1-bis ( 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 (A- 1-1) ~ Formula (A-1-3)

Respective compounds and the like; Examples of the diaminoorganosiloxane include 1,3-bis (3-aminopropyl) -tetramethyldisilaxane, etc .; in addition, Japanese patent special The diamine described in the 2010-97188 publication. These diamines can be used alone or in combination of two or more.

The diamine used when synthesizing the polyamidic acid of the present invention is preferably an aromatic diamine containing 30 mol% or more with respect to the total diamine, more preferably 50 mol% or more, and particularly preferably 80 mol. Ear%.

In addition, in the case of a liquid crystal alignment agent for a liquid crystal display element of a vertical alignment type, in order to impart good vertical alignment, it is preferable to use a diamine as a pretilt component. Specifically, examples of such a diamine having a pre-tilt component include: Dodecyloxy-2,4-diaminobenzene, tetradecyloxy-2,4-diaminobenzene, pentadecyloxy-2,4-diaminobenzene, hexadecyloxy -2,4-diaminobenzene, octadecyloxy-2,4-diaminobenzene, dodecyloxy-2,5-diaminobenzene, tetradecyloxy-2,5- Diaminobenzene, pentadecyloxy-2,5-diaminobenzene, hexadecyloxy-2,5-diaminobenzene, octadecyloxy-2,5-diaminobenzene, Cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, 3, Cholesteryl 5-diaminobenzoate, Cholesteryl 3,5-diaminobenzoate, Lanostyl 3,5-diaminobenzoate, 3,6-Bis (4 -Aminobenzyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 4- (4'-trifluoromethoxybenzyloxy) cyclohexyl -3,5-diaminobenzoate, 4- (4'-trifluoromethylbenzyloxy) cyclohexyl-3,5-diaminobenzoate, 1,1-bis ( 4-((aminophenyl) methyl) phenyl) -4-butylcyclohexane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4-heptyl Cyclohexane, 1,1-bis (4-((aminophenoxy) methyl) phenyl) -4-heptylcyclohexane, 1 1,1-bis (4-((aminophenyl) methyl) phenyl) -4- (4-heptylcyclohexyl) cyclohexane, a diamine represented by the above formula (A-1), and the like. Moreover, the diamine which has a pretilt component can be used individually by 1 type or in combination of 2 or more types.

The total amount of the diamine having a pretilt component is preferably 5 mol% or more, and more preferably 10 mol% or more with respect to the total diamine.

[Molecular weight regulator]

When synthesizing polyamic acid, a terminal-modified polymer can be synthesized with a tetracarboxylic dianhydride and diamine as described above using an appropriate molecular weight regulator. By forming such a terminal-modified polymer, it is possible to further improve the coatability (printability) of the liquid crystal alignment agent without impairing the effects of the present invention.

Examples of the molecular weight modifier include monoanhydrides, monoamine compounds, and monoisocyanate compounds. Specific examples of these molecular weight regulators include, for example, maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, and n-tetradecyl Succinic anhydride, n-hexadecyl succinic anhydride, etc. Examples of monoamine compounds include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, and the like. Monoisocyanate compounds may be Examples: phenyl isocyanate, naphthyl isocyanate, and the like.

The use ratio of the molecular weight regulator 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 tetracarboxylic dianhydride and diamine used.

<Synthesis of Polyamic Acid>

It is preferable that the use ratio of the tetracarboxylic dianhydride and the diamine used in the synthesis reaction of the polyamic acid of the present invention is that the acid anhydride group of the tetracarboxylic dianhydride is 0.2 equivalent to 2 with respect to 1 equivalent of the amine group of the diamine. The ratio of equivalents is more preferably a ratio of 0.3 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is preferably performed 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. The reaction time is preferably from 0.1 to 24 hours, and more preferably from 0.5 to 12 hours.

Examples of the organic solvent include aprotic polar solvents, phenol-based solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons.

As specific examples of these organic solvents, the above-mentioned examples of aprotic polar solvents Examples include: N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethyl-2-pyrrolidone, N, N-dimethylacetamidamine, N, N -Dimethylformamide, dimethylmethane, γ-butyrolactone, tetramethylurea, hexamethylphosphoric triamide, and the like; examples of the phenol-based solvent include: phenol, m-formyl Phenol, xylenol, halogenated phenol, etc .; examples of the alcohols include methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol Monomethyl ether and the like; examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; examples of the ester include ethyl lactate, butyl lactate, methyl acetate, Ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate, isoamyl propionate, isoamyl isobutyrate Examples of the ether include diethyl ether, diisoamyl ether, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, and ethylene glycol-n-butyl ether. , Ethylene glycol dimethyl ether, ethylene glycol Ether acetate, diethylene glycol 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, and the like; examples of the halogenated hydrocarbon include dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, and o-dichloro Benzene 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-based solvent (organic solvent of the first group), or 1 selected from the organic solvents of the first group is preferably used. More than one species selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons (organic solvents of the second group) to On the mixture. In the latter case, the use ratio of the organic solvent in the second group is preferably 50% by weight or less, and more preferably 40% by weight, with respect to the total amount of the organic solvent in the first group and the organic solvent in the second group. Hereinafter, it is particularly preferably 30% by weight or less.

The used amount of the organic solvent (a) is preferably an amount in which the total amount (b) of tetracarboxylic dianhydride and diamine is 0.1% to 50% by weight relative to the total amount (a + b) of the reaction solution. .

In the manner described above, a reaction solution obtained by dissolving polyamic acid was obtained. The reaction solution may be directly provided to the preparation of the liquid crystal alignment agent, or the polyamidic acid contained in the reaction solution may be isolated and then provided to the preparation of the liquid crystal alignment agent, or the isolated polyamidic acid may be purified and then Provided for preparation of liquid crystal alignment agent. In the case where the polyamidic acid is subjected to dehydration and ring closure to form a polyimide, the above reaction solution may be directly provided to the dehydration ring closure reaction, or the polyamidate contained in the reaction solution may be isolated and then supplied to the The dehydration ring closure reaction, or the isolated polyamidic acid may be purified and then provided to the dehydration ring closure reaction. Isolation and purification of polyamic acid can be performed according to a known method.

〈Polyimide and Synthesis of Polyimide〉

The polyfluorene imide contained in the liquid crystal alignment agent of the present invention can be obtained by dehydrating and closing the polyphosphonic acid synthesized in the above-mentioned manner, and then performing fluorimidization.

The polyfluorene imine may be a complete fluorinated imide obtained by dehydrating and closing all the fluorinated acid structures of the polyfluorinated acid as a precursor thereof, or may be dehydrated by dehydrating only a part of the fluorinated acid structure. Closing the ring makes the amino acid structure Part of the sulfonium imide coexisting with an imine ring structure. The polyimide ratio of the polyimide of the present invention is preferably 30% or more, more preferably 40% to 99%, and particularly preferably 50% to 99%. The fluorene imidization ratio is a percentage expressed as a percentage of the number of fluorene imine ring structures relative to the total number of fluorene acid structures and fluorene imine ring structures of the polyfluorene imine. Here, a part of the fluorene imine ring may be an isoimide ring.

The dehydration ring closure of the polyamic acid is preferably a method of heating the polyamic acid, or by dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring-closing catalyst to the solution, and heating as needed. Method to proceed. Among these, the latter method is preferably used.

In the method of adding a dehydrating agent and a dehydration ring-closing catalyst to the solution of the said polyamic acid, acid anhydrides, such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride, can be used as a dehydrating agent. The usage amount of the dehydrating agent is preferably 0.01 mol to 20 mol relative to 1 mol of the fluoric acid structure of the polyamic acid. Examples of the dehydration ring-closing catalyst include tertiary amines such as pyridine, collidine, lutidine, and triethylamine. The amount of the dehydration ring-closing catalyst used is preferably 0.01 to 10 mol relative to 1 mol of the dehydrating agent used. Examples of the organic solvent used in the dehydration ring-closing reaction include the organic solvents exemplified as the organic solvent for synthesizing polyamic acid. The reaction temperature of the dehydration ring-closing reaction is preferably 0 ° C to 180 ° C, and more preferably 10 ° C to 150 ° C. The reaction time is preferably 1.0 to 120 hours, and more preferably 2.0 to 30 hours.

A reaction solution containing polyfluoreneimine was obtained in the manner described above. The reaction solution can be directly provided to the preparation of the liquid crystal alignment agent, and the dehydration can also be removed from the reaction solution. Agent and dehydration ring-closing catalyst and then provided to the preparation of the liquid crystal alignment agent, the polyfluorene imide may be isolated and then provided to the preparation of the liquid crystal alignment agent, or the isolated polyfluorene imide may be purified and then provided to the liquid crystal alignment agent. Preparation of the agent. These purification operations can be performed according to well-known methods.

<Polyurethane>

The polyfluorinated acid ester contained in the liquid crystal alignment agent of the present invention can be obtained, for example, by the following method: [I] The polyfluorinated acid obtained by the above synthesis reaction and a hydroxyl-containing compound, a halide, an epoxy-containing compound [II] A method of reacting a tetracarboxylic acid diester with a diamine; [III] A method of reacting a tetracarboxylic acid diester dihalide with a diamine.

Here, examples of the hydroxyl-containing compound used in the method [I] include alcohols such as methanol, ethanol, and propanol; and phenols such as phenol and cresol. Examples of the halide include methyl bromide, bromoethane, bromooctadecane, methyl chloride, octadecyl chloride, 1,1,1-trifluoro-2-iodoethane, etc .; Examples of the epoxy-based compound include propylene oxide. The tetracarboxylic acid diester used in the method [II] can be obtained, for example, by using the above-mentioned alcohols and ring-opening the tetracarboxylic dianhydride exemplified in the synthesis of the polyamic acid. The tetracarboxylic acid diester dihalide used in the method [III] can be obtained by reacting the tetracarboxylic acid diester obtained in the above manner with an appropriate chlorinating agent such as thionyl chloride. As the diamine used in the method [II] and the method [III], the diamine and the like exemplified in the synthesis of the above-mentioned polyamic acid can be used. In addition, the polyamidate may have only a pseudoamidate structure, or may be a partially esterified product in which a pseudoamidate structure and a pseudoamidate structure coexist.

<Solution viscosity and weight average molecular weight of polymer>

The polyamidic acid, polyamidoimide, and polyamidate obtained in the above manner preferably have 10 mPa when they are made into a solution having a concentration of 10% by weight. s ~ 800mPa. The compound having a solution viscosity of s is more preferably 15 mPa. s ~ 500mPa. The solution viscosity of the compound. In addition, the solution viscosity (mPa.s) of the polymer is an E-type rotary viscometer. Good solvents (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, 1,3- Dimethyl-2-imidazolidinone, N-ethyl-2-pyrrolidone, etc.), a value obtained by measuring a polymer solution having a concentration of 10% by weight and measuring at 25 ° C. The polystyrene acid, polyimide, and polyamidate contained in the liquid crystal alignment agent of the present invention are measured in terms of polystyrene by gel-permeation chromatography (GPC). The weight average molecular weight is preferably 500 to 100,000, and more preferably 1,000 to 50,000.

<Polyorganosiloxane>

The polyorganosiloxane of the present invention can be hydrolyzed or hydrolyzed by, for example, preferably a hydrolyzable silane compound in the presence of a suitable organic solvent, water, and a catalyst. Obtained by condensation.

Examples of the hydrolyzable silane compound for synthesizing polyorganosiloxane include methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrichlorosilane, and phenyltrimethoxysilane , Phenyltriethoxysilane, methyldichlorosilane, methyldimethoxysilane, methyldiethoxysilane, dimethyldichlorosilane, dimethyldimethoxysilane, dimethyl Diethoxysilane, diphenyldichlorosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, chlorodimethylsilane, methyl Oxydimethylsilane, ethoxydimethylsilane, chlorotrimethylsilane, bromotrimethylsilane, iodotrimethylsilane, methoxytrimethylsilane, ethoxytrimethylsilane, tetramethylsilane Methoxysilane, tetraethoxysilane, octadecyltrichlorosilane, octadecyltrimethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, olefin Propyltrichlorosilane, allyltrimethoxysilane, allyltriethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyldimethylmethoxysilane, 3- Glycidyloxypropyldimethylethoxysilane, 2-glycidyloxyethyltrimethoxysilane, 2-glycidyloxyethyltriethoxysilane, 2-glycidyloxyethylmethyl Dimethoxysilane, 2-glycidyloxyethylmethyldiethoxysilane, 2-glycidyloxyethyldimethylmethoxysilane, 2- Glycidyloxyethyldimethylethoxysilane, 4-glycidyloxybutyltrimethoxysilane, 4-glycidyloxybutyltriethoxysilane, 4-glycidyloxybutylmethyldi Methoxysilane, 4-glycidyloxybutylmethyldiethoxysilane, 4-glycidyloxybutyldimethylmethoxysilane, 4-glycidyloxybutyldimethylethoxysilane , 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (3,4-epoxy ring Hexyl) propyltrimethoxysilane, 3- (3,4-epoxycyclohexyl) propyltriethoxysilane, (3-ethyloxetane-3-yl) methacrylate Ester, (3-methyloxetane-3-yl) methyl (meth) acrylate, 3- (meth) acryloxypropyltrichlorosilane, 3- (meth) acryloxy Propyl Trimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 2- (meth) acryloxyethyltrichlorosilane, 2- (meth) acryloxyethyl Trimethoxysilane, 2- (meth) propenyloxyethyltriethoxysilane, 4- (meth) propenyloxybutyltrichlorosilane, 4- (meth) propenyloxy Butyltrimethoxysilane, 4- (meth) acryloxybutyltriethoxysilane, and the like. In addition, "(meth) acryloxy" means a meaning including "acryloxy" and "methacryloxy".

Examples of organic solvents that can be used in the synthesis of polyorganosiloxanes include hydrocarbons, ketones, esters, ethers, and alcohols. Examples of the hydrocarbon include toluene and xylene. Examples of the ketone include methyl ethyl ketone, methyl isobutyl ketone, methyl n-pentyl ketone, diethyl ketone, and cyclohexanone. Examples of the ester include ethyl acetate, n-butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, and ethyl lactate; examples of the ether include : Ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, dioxane, etc. Examples of the above-mentioned alcohols include 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether, ethyl Glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, and the like. Among these organic solvents, a water-insoluble organic solvent is preferably used. These organic solvents may be used singly or in combination of two or more.

The usage-amount of the organic solvent in the case of synthesizing the said polyorganosiloxane is 100 weight part-10,000 weight part with respect to 100 weight part of total silane compounds, More preferably, it is 50 weight part-1,000 weight part. In addition, the amount of water used in the production of the polyorganosiloxane is preferably 0.5 to 100 times mol, and more preferably 1 to 30 times mol relative to the total silane compound used.

Examples of the catalyst that can be used in the synthesis of the polyorganosiloxane include an acid, an alkali metal compound, an organic base, a titanium compound, and a zirconium compound. Here, examples of the acid include hydrochloric acid, sulfuric acid, nitric acid, formic acid, oxalic acid, acetic acid, trifluoroacetic acid, trifluoromethanesulfonic acid, and phosphoric acid. Examples of the alkali metal compound include sodium hydroxide and hydroxide. Potassium, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, etc .; the organic bases include, for example, primary, secondary, and secondary organic amines such as ethylamine, diethylamine, piperazine, piperidine, pyrrolidine, and pyrrole. Tertiary organic amines such as ethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, 4-dimethylaminopyridine, diazabicycloundecene, and tetramethylammonium hydroxide Class quaternary organic amines and so on.

The catalyst is particularly preferably an organic base. The amount of organic base used varies according to the type of organic base, reaction conditions such as temperature, etc., and should be appropriately set. For example, it is preferably 0.01 to 3 times mole, more preferably 0.05 times mole relative to the total silane compound. Ears ~ 1 mole.

Hydrolysis or hydrolysis when manufacturing the above polyorganosiloxane. The condensation reaction is preferably carried out by dissolving one or two or more types of hydrolyzable silane compounds in an organic solvent, mixing the obtained solution with an organic base and water, and heating the mixture with an oil bath or the like, for example.

hydrolysis. In the condensation reaction, the heating temperature is preferably 130 ° C or lower, more preferably 40 ° C to 100 ° C, preferably 0.5 to 12 hours, and more preferably 1 to 8 hours. During heating, the mixed solution may be stirred or placed under reflux conditions.

After completion of the reaction, the organic solvent layer fractionated from the reaction solution is preferably Washed with water. When performing this washing | cleaning, it is preferable to wash | clean with water containing a small amount of salt, for example, about 0.2 weight% of ammonium nitrate aqueous solution etc. from the point which makes a washing | cleaning operation easy. The washing can be performed until the water layer after the washing becomes neutral, and then the organic solvent layer is dried with a desiccant such as anhydrous calcium sulfate and molecular sieves, if necessary, and then the solvent is removed to obtain the target polyorganic Siloxane. Moreover, you may use a commercial item as the polyorganosiloxane of this invention.

The polyorganosiloxane contained in the liquid crystal alignment agent of the present invention can be reacted with a reactive polyorganosiloxane obtained by the above-mentioned condensation reaction with a reactive compound. A polyorganosiloxane having a structure derived from a reactive compound is introduced into the chain. Examples of the reactive polyorganosiloxane include polyorganosiloxane having an epoxy group, an unsaturated double bond, a mercapto group, and an amine group. Examples of the reactive compound include a compound having a long-chain alkyl group, a compound having a structure in which two or more rings (such as a benzene ring or a cyclohexane ring) are connected, a compound having a steroid skeleton, and a compound having a steroid skeleton. Compounds with saturated double bonds, etc.

In addition, the reaction between the reactive polyorganosiloxane and the reactive compound can be performed according to a common method of organic chemistry. For example, when the reactive polyorganosiloxane has an epoxy group, a structure derived from the reactive compound can be introduced into the side chain of the reactive polyorganosiloxane by using a carboxylic acid as the reactive compound. In addition, in the case where the reactive polyorganosiloxane has an unsaturated double bond, a compound having a mercapto group or an amine group can be used as a reactive compound, and the source can be introduced into the side chain of the reactive polyorganosiloxane. Structure of a reactive compound.

Polystyrene measured by GPC in the polyorganosiloxane of the present invention The converted weight average molecular weight is preferably 500 to 100,000, more preferably 1,000 to 30,000, and particularly preferably 1,000 to 20,000.

<Solvent>

The solvent contained in the liquid crystal alignment agent of the present invention is used to dissolve the polymer component described above or to improve the applicability when the liquid crystal alignment agent is applied to a substrate. In particular, the liquid crystal alignment agent of the present invention contains at least a compound (p1) represented by the following formula (1) as a solvent component. This compound (p1) has properties not only that it has good coatability to a substrate, but also that it is difficult to swell the APR resin on a printing plate of a printing machine generally used for a liquid crystal alignment agent. By using such a compound (p1) as a solvent, it is possible to make it difficult for the solvent to penetrate into the printing plate during printing. In addition, even in the case of continuous printing, it is difficult to precipitate a polymer component on the printing press, and continuous printing properties are also good.

(In the formula (1), R ¹ and R ³ are each independently a linear or branched monovalent hydrocarbon group having 1 to 3 carbon atoms, and R ² is a linear or branched carbon number 2 to 5 Alkanediyl.)

In R ¹ and R ³ in the formula (1), a hydrocarbon group having 1 to 3 carbon atoms may be saturated or unsaturated, and may be linear or branched. Specific examples of R ¹ and R ³ include, for example, alkyl groups having 1 to 3 carbon atoms such as methyl, ethyl, n-propyl, and isopropyl; monovalent groups having 2 or 3 carbon atoms such as vinyl and allyl; Unsaturated hydrocarbyl and the like. Preferably, R ¹ and R ³ are methyl. In formula (1), R ¹ and R ³ may be the same as or different from each other.

The alkanediyl group having 2 to 5 carbon atoms of R ² may be linear or branched. Specific examples thereof include ethylidene, propane-1,2-diyl, and propane-1,3. -Diyl, butane-1,3-diyl, butane-1,4-diyl, pentane-1,5-diyl, and the like.

Preferred specific examples of the compound (p1) include, for example, alkylene glycol diacetate such as ethylene glycol diacetate and propylene glycol diacetate. Among these, propylene glycol diacetate can be preferably used.

From the viewpoint of improving the applicability of the liquid crystal alignment agent when applied to a substrate, the content of the compound (p1) is preferably 5% by weight or more with respect to the total amount of the solvent contained in the liquid crystal alignment agent, and more preferably 10% by weight or more. From the viewpoint of suppressing the precipitation of the polymer, the upper limit of the content of the compound (p1) is preferably 90% by weight or less, and more preferably 70% by weight or less, with respect to the total amount of the solvent contained in the liquid crystal alignment agent. It is preferably 50% by weight or less.

[Compound (p2)]

The solvent contained in the liquid crystal alignment agent of the present invention preferably contains not only the compound (p1) but also a compound selected from the group consisting of 1,3-dimethyl-2-imidazolidinone and the following formula (2) And at least one compound (p2) in the group consisting of the compound represented by the following formula (3). These compounds (p2) can all dissolve the polymer (A), and have a moderately high boiling point. Therefore, by using these organic solvents as the solvent component of the liquid crystal alignment agent, when the liquid crystal alignment agent is printed on the substrate, it is possible to suppress volatilization of the solvent from the printer and to suppress the precipitation of polymer components on the printer. In addition, since the boiling point of the solvent is not too high, pre-heating (pre-baking) is performed after printing. In the case of baking, the amount of solvent remaining in the coating film after preheating can be reduced. Accordingly, it is possible to prevent dust from adhering to the surface of the coating film after the preheating, and it is possible to suppress a decrease in the yield of the product.

(In formula (2), R ⁴ and R ⁵ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a monovalent group containing "-O-" between carbon-carbon bonds of the hydrocarbon group, R ⁴ and R ⁵ may be bonded to each other to form a ring structure; R ⁶ is an alkyl group having 1 to 6 carbon atoms.)

(In formula (3), R ⁷ is a monovalent hydrocarbon group having 2 to 5 carbon atoms or a monovalent group containing "-O-" between carbon-carbon bonds in the hydrocarbon group.)

[Compound represented by the above formula (2)]

The monovalent hydrocarbon group having 1 to 6 carbon atoms of R ⁴ and R ⁵ in the formula (2) may be saturated or unsaturated. R ⁴ and R ⁵ may be a group containing “—O—” between carbon-carbon single bonds in a monovalent hydrocarbon group having 1 to 6 carbon atoms. Specific examples of R ⁴ and R ⁵ include, for example, alkyl groups having 1 to 6 carbon atoms, alicyclic hydrocarbon groups having 3 to 6 carbon atoms, and aromatic hydrocarbon groups having 5 or 6 carbon atoms. The carbon-carbon bond contains a group such as "-O-". In formula (1), R ⁴ and R ⁵ may be the same as or different from each other.

Examples of the alkyl group having 1 to 6 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, second butyl, isobutyl, third butyl, pentyl, and the like. Jiji et al. Examples of the alicyclic hydrocarbon group having 3 to 6 carbon atoms include cyclopentyl and cyclohexyl. Examples of the aromatic hydrocarbon group having 5 or 6 carbon atoms include a phenyl group and the like.

R ⁴ and R ⁵ may be bonded to each other to form a ring with the nitrogen atom to which R ⁴ and R ⁵ are bonded. Examples of the ring formed by bonding R ⁴ and R ^{5 to} each other include a pyrrolidine ring and a piperidine ring. A monovalent chain hydrocarbon group such as a methyl group may be bonded to these rings.

R ⁴ and R ^{5 are} preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group.

The alkyl group having 1 to 6 carbon atoms of R ⁶ may be linear or branched. Specifically, the alkyl group having 1 to 6 carbon atoms of R ⁴ and R ⁵ may be exemplified in the description. Group.

Specific examples of the compound represented by the formula (2) include 3-butoxy-N, N-dimethylpropanamide, 3-methoxy-N, N-dimethylpropanamide, 3-hexyloxy-N, N-dimethylpropionamine, isopropoxy-N-isopropyl-propionamine, n-butoxy-N-isopropyl-propionamine and the like.

[Compound represented by the above formula (3)]

The monovalent hydrocarbon group having 2 to 5 carbon atoms of R ⁷ in the formula (3) may be saturated or unsaturated, and may be linear or branched. R ⁷ may be a monovalent group containing "-O-" between carbon-carbon single bonds of a monovalent hydrocarbon group having 2 to 5 carbon atoms. Specific examples of R ⁷ include, for example, an alkyl group, alkenyl group, and alkynyl group having 2 to 5 carbon atoms, and a group including "-O-" between the carbon-carbon single bonds in these groups ( Hereinafter also referred to as "oxy-containing").

Examples of the alkyl group having 2 to 5 carbon atoms of R ⁷ include ethyl, n-propyl, isopropyl, n-butyl, second butyl, isobutyl, third butyl, n-pentyl, and the like. Isoamyl, etc .; Examples of alkenyl groups having 2 to 5 carbon atoms include vinyl, 1-propenyl, 2-propenyl, 1-methylvinyl, 2-methyl-1-propenyl, etc .; carbon number 2 Examples of the ~ 5 alkynyl group include ethynyl, 2-propynyl, and 2-butynyl.

Examples of the oxygen-containing group include alkoxyalkyl groups having 2 to 5 carbon atoms. Specific examples include methoxymethyl, methoxyethyl, methoxypropyl, and methoxy. Butyl, ethoxymethyl, ethoxyethyl and the like.

R ⁷ is preferably an alkyl or alkoxyalkyl group having 2 to 5 carbon atoms as described above.

Specific examples of the compound represented by the formula (3) include N-ethyl-2-pyrrolidone, N-propyl-2-pyrrolidone, N-butyl-2-pyrrolidone, and N- (third-butyl) ) -2-pyrrolidone, N-pentyl-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone Wait. Among these compounds, N-ethyl-2-pyrrolidone, N-pentyl-2-pyrrolidone, N- (third butyl) -2-pyrrolidone, N-methoxypropyl-2-pyrrolidone can be particularly preferably used. . The compound represented by the formula (3) may be used alone or in combination of two or more of these exemplified compounds.

From the viewpoint of the solubility of the polymer component, with respect to the alignment of the liquid crystal The total amount of the solvent contained in the agent is preferably 5% by weight or more, and more preferably 10% by weight or more. The upper limit of the content is not particularly limited, but is preferably 90% by weight or less with respect to the total amount of the solvent contained in the liquid crystal alignment agent. The compound (p2) may be used alone or in combination of two or more kinds.

[Other solvents]

As the solvent for preparing the liquid crystal alignment agent of the present invention, solvents other than the aforementioned compound (p1) and compound (p2) can also be used. Examples of the other solvents include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, and N, N-dimethylacetamide. , 4-hydroxy-4-methyl-2-pentanone (diacetone alcohol), ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate , Ethylene glycol 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 Alcohol ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol Alcohol monoethyl ether acetate, dipropylene glycol monomethylether (DPM), diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, ethyl carbonate, carbonic acid Propylene ester, 3 butanol, 3 pentanol and so on. In addition, other solvents may be used singly or in combination of two or more kinds.

In addition, the solvent component in the liquid crystal alignment agent of the present invention can further suppress a printing plate by using a tertiary alcohol such as diacetone alcohol, third butanol, and third pentanol with the compound (p1) as the other solvent. (APR version) swelling, Therefore, it is preferable.

From the viewpoint of improving printability, the content of the other solvents is preferably 80% by weight or less, more preferably 50% by weight or less, and particularly preferably 30% by weight, with respect to the total amount of the solvents contained in the liquid crystal alignment agent. the following. When tertiary alcohols are used as other solvents, the content of the other solvents is preferably 1% to 50% by weight, and more preferably 5% to 5% by weight, relative to the total amount of the solvents contained in the liquid crystal alignment agent. 40% by weight.

〈Other additives〉

The liquid crystal alignment agent of the present invention contains the polymer and the solvent as described above, and may contain other components as necessary. Examples of the other components include polymers other than the above-mentioned polymers, compounds having at least one epoxy group in the molecule (hereinafter referred to as "epoxy-containing compounds"), functional silane compounds, and the like.

[Other polymers]

The other polymers mentioned above can be used to improve solution properties or electrical properties. Examples of the other polymers include polyesters, polyamidoamines, cellulose derivatives, polyacetals, polystyrene derivatives, poly (styrene-phenylmaleimide diimines) derivatives, and poly ( (Meth) acrylates and the like. When the other polymer is added to the liquid crystal alignment agent, the blending ratio of the other polymer is preferably 50% by weight or less, and more preferably 0.1 to 40% by weight, relative to the total amount of polymers in the composition. The weight% is particularly preferably 0.1% to 30% by weight.

[Epoxy-containing compound]

Epoxy-containing compounds can be used to improve adhesion of liquid crystal alignment films to substrate surfaces 着 性。 Sex. Examples of the epoxy group-containing compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, 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 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 ring Hexane, N, N-diglycidyl-cyclohexylamine and the like.

When these epoxy compounds are added to the liquid crystal alignment agent, the blending ratio of the epoxy compound is preferably 40 parts by weight or less, more preferably 100 parts by weight with respect to the total amount of the polymer contained in the liquid crystal alignment agent. 0.1 parts by weight to 30 parts by weight.

[Functional silane compound]

The said functional silane compound can be used for the objective of improving the printability of a liquid crystal aligning agent. Examples of such a functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, and 2-aminopropyl Triethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxy Silane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-triethoxy Silylpropyltriethylene triamine, 10-trimethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl Acetate, 9-trimethoxysilyl-3,6-diazanonanoic acid methyl ester, N-benzyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyl Trimethoxysilane, glycidyloxymethyltrimethoxysilane, 2-glycidyloxyethyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, and the like.

When these functional silane compounds are added to a liquid crystal alignment agent, the blending ratio of the functional silane compound is preferably 2 parts by weight or less, and more preferably 0.02 to 0.2 parts by weight, based on 100 parts by weight of the total polymer. Parts by weight.

In addition to the other additives contained in the liquid crystal alignment agent, a compound having at least one oxetanyl group in the molecule, an antioxidant, or the like can be used.

The solid content concentration (the ratio of the total weight of components other than the solvent of the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent) in the liquid crystal alignment agent of the present invention is appropriately selected in consideration of viscosity, volatility, and the like, and is preferably selected. The range is 1% to 10% by weight. That is, the liquid crystal alignment agent of the present invention is applied to the surface of a substrate by a method described later, and it is preferable to form a coating film as a liquid crystal alignment film or a coating film as a liquid crystal alignment film by heating, but at this time, the solid content concentration is less than 1 In the case of% by weight, the film thickness of the coating film becomes too small to obtain a good 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 a good liquid crystal alignment film cannot be obtained. In addition, the viscosity of the liquid crystal alignment agent increases, and the coating characteristics deteriorate.

The range of a particularly preferable solid content concentration differs according to the method used when apply | coating a liquid crystal aligning agent on a board | substrate. For example, when using a spin coating method, the solid content concentration is particularly preferably in a range of 1.5% to 4.5% by weight. Using In the case of the lithographic printing method, it is particularly preferable to set the solid content concentration to a range of 3% to 9% by weight, and thereby set the solution viscosity to 12 mPa. s ~ 50mPa. The range 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% to 5% by weight, and thereby set the solution viscosity to 3 mPa. s ~ 15mPa. The range of s.

The temperature when preparing the liquid crystal alignment agent of the present invention is preferably 10 ° C to 50 ° C, and more preferably 20 ° C to 30 ° C.

<Liquid crystal alignment film and liquid crystal display element>

The liquid crystal alignment film of the present invention is formed using the liquid crystal alignment agent prepared in the above manner. The liquid crystal display element of the present invention includes a liquid crystal alignment film formed using the liquid crystal alignment agent of the present invention. The driving mode of the liquid crystal display element to which the present invention is applied is not particularly limited, and can be applied to various driving modes such as TN type, STN type, IPS type, FFS type, VA type, and MVA type. Hereinafter, the manufacturing method of the liquid crystal display element of this invention is demonstrated, and the manufacturing method of the liquid crystal alignment film of this invention is demonstrated in this description.

The liquid crystal display element of the present invention can be manufactured by the following steps (1) to (3), for example. Step (1) uses different substrates depending on the required driving mode. Steps (2) and (3) are common to each driving mode.

[Step (1): Formation of Coating Film]

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

(1-1) When manufacturing a TN-type, STN-type, or VA-type liquid crystal display element, two substrates provided with a patterned transparent conductive film are used as a pair, and the transparent conductive film formation surfaces Preferably, the liquid crystal alignment agent of the present invention is applied by a lithographic printing method, a spin coating method, a roll coater method, or an inkjet printing method. The coating method of a liquid crystal aligning agent can be preferably applied to the lithographic method among these coating methods. Therefore, for the substrate, for example, glass such as float glass and soda glass can be used. Polyethylene terephthalate, polybutylene terephthalate, polyether fluorene, and polycarbonate can be used. , Poly (alicyclic olefin) and other plastic transparent substrates. As the transparent conductive film provided on one side of the substrate, a NESA film (registered trademark of the United States PPG Corporation) containing tin oxide (SnO ₂ ), an ITO film containing indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), or the like can be used. In order to obtain a patterned transparent conductive film, for example, the following methods can be used: a method of forming a pattern by photo etching after forming a patternless transparent conductive film; using a mask having a desired pattern when forming a transparent conductive film Hood method and so on. When the liquid crystal alignment agent is applied, in order to improve the adhesion between the substrate surface and the transparent conductive film and the coating film, the surface on the substrate surface where the coating film is to be formed may be previously coated with a functional silane compound or a functional titanium compound. deal with.

After the liquid crystal alignment agent is applied, it is preferable to perform preheating (prebaking) for the purpose of preventing sagging of the applied alignment agent. The pre-baking temperature is preferably 30 ° C to 200 ° C, more preferably 40 ° C to 150 ° C, and particularly preferably 40 ° C to 100 ° C. The pre-baking time is preferably 0.25 minutes to 10 minutes, and more preferably 0.5 minutes to 5 minutes. Then, the solvent is completely removed, and if necessary, a calcination (postbake) step is performed for the purpose of subjecting the arsenic acid structure present in the polymer to thermal arsonization. The calcination (post-baking) temperature is preferably 80 ° C to 300 ° C, and more preferably 120 ° C to 250 ° C. The post-baking time is preferably 5 minutes to 200 minutes, and more preferably 10 minutes to 100 minutes. In this way, the film thickness of the formed film 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 formation surface of a substrate provided with an electrode including a transparent conductive film or a metal film patterned in a comb-tooth shape, and a substrate provided with no electrode The liquid crystal aligning agent of the present invention is coated on one side of the electrodes facing the substrate, and then each coated surface is heated to form a coating film. The material, coating method, heating conditions after coating, the method of patterning the transparent conductive film or metal film, the substrate pre-treatment, and the preferred film thickness of the formed coating film used in this case are the same as the above (1 -1) The same. As the metal film, for example, a film containing a metal such as chromium can be used.

In any of the cases (1-1) and (1-2), a coating film to be an alignment film is formed by applying a liquid crystal alignment agent on a substrate and then removing an organic solvent. At this time, the polymer contained in the liquid crystal alignment agent of the present invention is a polyfluorinated acid, or a fluorinated polymer having a fluorinated imine ring structure and a fluorinated acid structure, or a fluorinated acid ester In the case of a polymer having a structure and a phosphine structure, a dehydration ring-closing reaction may be performed by further heating after the coating film is formed to form a coating film which is further imidized.

[Step (2): Alignment Capability Provisioning Process]

Next, the coating film formed on the substrate is subjected to a rubbing treatment or a light irradiation treatment as necessary to give the coating film a liquid crystal alignment ability.

First, regarding the rubbing treatment, in the case of manufacturing a TN, STN, IPS, or FFS liquid crystal display element, the coating film formed in the step (1) is subjected to the following rubbing treatment. Rollers of cloths made of fibers such as nylon, rayon, and cotton are wiped in a certain direction. As a result, the alignment ability of the liquid crystal molecules is imparted to the coating film to become a liquid crystal alignment film. On the other hand, in the case of manufacturing a VA-type liquid crystal display element, the coating film formed in the step (1) may be used as a liquid crystal alignment film directly, but the coating film may be subjected to a rubbing treatment.

In addition, the liquid crystal alignment film after the rubbing treatment may be further subjected to the following processing: a process of changing the pretilt angle of a part of the liquid crystal alignment film by irradiating a part of the liquid crystal alignment film with ultraviolet rays; After the resist film, the rubbing treatment is performed in a direction different from the previous rubbing treatment, and then the resist film is removed; thereby 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.

On the other hand, in the case of using a light irradiation process (light alignment method), the substrate after the coating film is formed is irradiated with polarized or unpolarized radiation to the coating film surface to give the coating film liquid crystal alignment ability. Here, as the radiation, for example, ultraviolet rays or visible rays including light having a wavelength of 150 to 800 nm can be used. Among these, ultraviolet rays including light having a wavelength of 300 nm to 400 nm are preferred. When the radiation used is polarized (linearly polarized or partially polarized), the light irradiation direction may be a direction perpendicular to the coating film surface, or may be an oblique direction in order to give a pretilt angle. On the other hand, when irradiating non-polarized light, it is necessary to The coating film surface is irradiated with light.

The light source may be, for example, a low pressure mercury lamp, a high pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, or a xenon lamp. (xenon lamp), excimer laser, etc. The ultraviolet rays in the above-mentioned preferable 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, and the like. The radiation dose is preferably 1 J / m ² or more and less than 10,000 J / m ² , and more preferably 10 J / m ² to 5,000 J / m ² .

[Step (3): Construction of Liquid Crystal Cell]

A liquid crystal cell is manufactured by preparing two substrates on which the liquid crystal alignment film is formed as described above, and arranging liquid crystal between the two substrates disposed opposite to each other. When manufacturing a liquid crystal cell, the following two methods are mentioned, for example.

The first method is a previously known method. First, two liquid crystal alignment films are opposed to each other, and two substrates are arranged to face each other across a gap (cell gap), and the peripheral portions of the two substrates are bonded using a sealant, and the cells are divided by the substrate surface and the sealant. After the liquid crystal is injected into the gap and the injection hole is sealed, a liquid crystal cell can be manufactured. The second method is a method called a One Drop Fill (ODF) method. A predetermined position on one of the two substrates on which the liquid crystal alignment film is formed may be coated with, for example, a UV-curable sealing material, and the liquid crystal may be added dropwise to predetermined positions on the liquid crystal alignment film surface. Laminate another substrate with the liquid crystal alignment film facing each other, and press the liquid crystal across the entire surface of the substrate, 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 either method, it is desirable that the liquid crystal cell manufactured as described above is further heated to a temperature at which the used liquid crystal becomes an isotropic phase, and then is gradually cooled to room temperature, so that Removes flow alignment during liquid crystal filling.

As the sealant, for example, an epoxy resin containing a hardener and alumina balls as a spacer can be used.

Examples of the liquid crystal include a nematic liquid crystal and a smectic liquid crystal. Among them, a nematic liquid crystal is preferred. For example, a Schiff base liquid crystal and azoxy are used. ) -Based liquid crystal, biphenyl-based liquid crystal, phenylcyclohexane-based liquid crystal, ester-based liquid crystal, terphenyl-based liquid crystal, biphenylcyclohexane-based liquid crystal, pyrimidine-based liquid crystal, dioxane-based liquid crystal, dicyclooctyl Alkane-based liquid crystals, cubane-based liquid crystals, and the like. In addition, the following substances may be added to these liquid crystals and used, for example, cholesterol liquid crystals such as cholesteryl chloride, cholesteryl nonanoate, and cholesteryl carbonate. ; Chiral agents sold as trade names "C-15" and "CB-15" (manufactured by Merck); p-decoxyphenylmethylene-p-amino-2- Ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate and the like.

Next, by attaching a polarizing plate to the outer surface of the liquid crystal cell, The liquid crystal display element of the present invention. Examples of the polarizing plate attached to the outer surface of the liquid crystal cell include a polarizing plate in which a polarizing film called "H film" is supported by a cellulose acetate protective film, and the "H film" is oriented while extending the polyvinyl alcohol. A film that allows one side to absorb iodine; or a polarizing plate containing the H film itself.

In addition, when the coating film is subjected to a rubbing treatment, the two substrates are arranged to face each other such that the rubbing directions in the respective coating films form a predetermined angle with each other, such as orthogonal or antiparallel. In addition, when the coating film is irradiated with light, if the liquid crystal alignment film is horizontally aligned, the angle formed by the polarization direction of the linearly polarized radiation irradiated in the two substrates on which the liquid crystal alignment film is formed, and The angle between each substrate and the polarizing plate can obtain a liquid crystal display element having a TN-type or STN-type liquid crystal cell. On the other hand, when the liquid crystal alignment film is vertically aligned, a unit is configured so that the directions of easy alignment axes of the two substrates on which the liquid crystal alignment film is formed become parallel, and the polarizing plate is formed on the unit. The polarization direction is bonded to the alignment easy axis at a 45 ° angle, and a liquid crystal display element having a vertical alignment type liquid crystal cell can be manufactured.

The liquid crystal display element of the present invention can be effectively applied to a variety of devices, for example, it can be used in clocks, portable video games, word processors, note type personal computers, Car navigation system, camcorder, personal digital assistant (PDA), digital camera, mobile phone, smartphone, various monitors, Display devices such as liquid crystal televisions.

[Example]

Hereinafter, the present invention will be further specifically described using examples, but the present invention is not limited by these examples.

The solution viscosity of each polymer solution in the synthesis example, the fluorene imidization ratio of polyfluorene, the weight average molecular weight, and the epoxy equivalent were measured by the following methods.

[Solution viscosity of polymer solution]

The solution viscosity (mPa.s) of the polymer solution was measured at 25 ° C. using a E-type rotary viscometer, a solution adjusted to a polymer concentration of 10% by weight using a predetermined solvent.

[Perylene imidation rate of polyimide]

A solution of polyfluoreneimide was poured into pure water, and the resulting precipitate was sufficiently dried under reduced pressure at room temperature, and then dissolved in deuterated dimethylsulfine. Tetramethylsilane was used as a reference substance at room temperature. ¹ H- NMR measurement ^{(1 H-Nuclear Magnetic Resonance,} 1 H-NMR). Based on the obtained ¹ H-NMR spectrum, the hydrazone imidization ratio [%] was determined by the following mathematical formula (1).

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

(In Mathematical Formula (1), A ¹ is the peak area of NH-derived protons appearing near the chemical shift of 10 ppm, A ² is the peak area of other protons, and α is the precursor of other protons to the polymer ( Proportion of the number of one proton of the NH group in the polyamidic acid).

[Polymer average molecular weight]

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

Column: Made by Tosoh, TSKgelGRCXLII

Solvent: Tetrahydrofuran

Temperature: 40 ° C

Pressure: 68kgf / cm ²

[Epoxy equivalent]

The epoxy equivalent is measured by the hydrochloric acid-methyl ethyl ketone method described in JIS C 2105.

<Synthesis of Polymer (A)> [Synthesis Example 1: Synthesis of Polyfluorene (PI-1)]

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentylacetic 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 was dissolved in 166 g of N-methyl-2-pyrrolidone (NMP) and reacted at 60 ° C. for 6 hours to obtain 20 weights of polyamino acid %The solution. A small amount of the obtained polyamic acid solution was fractionated, and NMP was added to prepare a solution having a polyamic acid concentration of 10% by weight. The viscosity of the solution obtained by measuring the solution was 90 mPa. s.

Next, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 7% by weight, 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and a dehydration ring-closure reaction was performed at 110 ° C. for 4 hours. After the dehydration closed-loop reaction, NMP solvent-replaces the solvent in the system (by this operation, pyridine and acetic anhydride used in the dehydration ring-closing reaction are removed from the system; the same applies hereinafter), thereby obtaining a polyfluorene containing a fluorene imine rate of about 68% A solution of 26% by weight of imine (PI-1). A small amount of the obtained polyfluorene imine solution was fractionated, and NMP was added to prepare a solution having a polyfluorene imine concentration of 10% by weight. The viscosity of the solution measured by the solution was 45 mPa. s. Next, the reaction solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyimide (PI-1).

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

22.5 g (0.1 mol) of 2,3,5-tricarboxycyclopentylacetic dianhydride as tetracarboxylic dianhydride, 7.6 g (0.07 mol) of p-phenylenediamine as diamine, 3,5- 5.2 g (0.01 mol) of cholesteryl diaminobenzoate and 4.0 g (0.02 mol) of 4,4'-diaminodiphenylmethane were dissolved in 157 g of NMP, and the reaction was performed at 60 ° C for 6 After reacting for hours, a 20% by weight solution containing polyamic acid was obtained. A small amount of the obtained polyamic acid solution was fractionated, and NMP was added to prepare a solution having a polyamic acid concentration of 10% by weight. The solution viscosity obtained by measuring the solution was 110 mPa. s.

Next, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 7% by weight, 16.6 g of pyridine and 21.4 g of acetic anhydride were added, and a dehydration ring-closure reaction was performed at 110 ° C for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with a new NMP to obtain a solution containing 26% by weight of polyfluoreneimine (PI-2) having a fluorinated imidization rate of about 82%. A small amount of the obtained polyimide solution was fractionated, and NMP was added to prepare a solution having a polyimide concentration of 10% by weight. The solution viscosity measured by this solution was 62mPa. s. Next, the reaction solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyimide (PI-2).

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

As a tetracarboxylic dianhydride, 2,4.9,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-dianhydride 24.9 g (0.10 mole), and a diamine pair 8.6 g (0.08 mole) of phenylenediamine and 10.4 g (0.02 mole) of cholestyryl 3,5-diaminobenzoate were dissolved in 176 g of NMP and reacted at 60 ° C for 6 hours to obtain 20% by weight solution of polyamic acid. A small amount of the obtained polyamic acid solution was fractionated, and NMP was added to prepare a solution having a polyamic acid concentration of 10% by weight. The solution viscosity obtained by measuring the solution was 103 mPa. s.

Next, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 7% by weight, 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and a dehydration ring-closure reaction was performed at 110 ° C for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with a new NMP to obtain a solution containing 26% by weight of polyfluorene imine (PI-3) having a fluorene imidization rate of about 71%. A small amount of the obtained polyfluorene imine solution was fractionated, and NMP was added to prepare a solution having a polyfluorene imine concentration of 10% by weight. The viscosity of the solution measured by the solution was 57 mPa. s. Next, the reaction solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyimide (PI-3).

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

110 g of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as a tetracarboxylic dianhydride (0.50 Mol) and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furyl) naphtho [1,2- c) 160 g (0.50 mole) of furan-1,3-dione, 91 g (0.85 mole) of p-phenylenediamine as diamine, 1,3-bis (3-aminopropyl) tetramethyldisilazide 25 g (0.10 mole) of oxane and 25 g (0.040 mole) of 3,6-bis (4-aminobenzyloxy) cholestane, and 1.4 g (0.015 mole) of aniline as a monoamine were dissolved in In 960 g of NMP, a reaction was performed at 60 ° C. for 6 hours to obtain a polyamic acid-containing solution. A small amount of the obtained polyamic acid solution was fractionated, and NMP was added to prepare a solution having a polyamic acid concentration of 10% by weight, and the solution viscosity obtained by measuring the solution was 60 mPa. s.

Next, 2,700 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 410 g of acetic anhydride were added, and a dehydration ring-closure reaction was performed at 110 ° C for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with a new γ-butyrolactone to obtain a solution containing 15% by weight of polyimide (PI-4) with a fluorene imidization rate of about 95%. About 2,500g. A small amount of this solution was fractionated, and NMP was added to prepare a solution having a polyimide concentration of 10% by weight. The solution viscosity obtained by measuring the solution was 70 mPa. s. Next, the reaction solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyimide (PI-4).

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

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

Next, 360 g of NMP was added to the obtained polyamic acid solution, 39.5 g of pyridine and 30.6 g of acetic anhydride were added, and a dehydration ring-closure reaction was performed at 110 ° C for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with a new NMP to obtain a solution containing 10% by weight of polyfluorene imine (PI-5) having a fluorinated imidization rate of about 93%. A small amount of the obtained polyfluorene imine solution was fractionated, and the solution viscosity measured by the solution was 30 mPa. s. Next, the reaction solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyimide (PI-5).

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

The same method as in Synthesis Example 1 was used except that the diamine used was changed to 0.08 moles of 3,5-diaminobenzoic acid and 0.02 moles of cholestyloxy-2,4-diaminobenzene. Methods A polyamic acid solution was obtained. A small amount of the obtained polyamic acid solution was fractionated, and NMP was added to prepare a solution having a polyamic acid concentration of 10% by weight, and the solution viscosity obtained by measuring the solution was 80 mPa. s.

Next, fluorene imidization was performed by the same method as in Synthesis Example 1 above to obtain a solution containing 26% by weight of polyfluorene imine (PI-6) with a fluorene imidization rate of about 65%. A small amount of the obtained polyfluorene imine solution was fractionated, and NMP was added to prepare a solution having a polyfluorene imine concentration of 10% by weight. The solution viscosity obtained by measuring the solution was 40 mPa. s. Next, the reaction solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyimide (PI-6).

[Synthesis Example 7: Synthesis of Polyamidic Acid (PA-1)]

200 g (1.0 mole) of 1,2,3,4-cyclobutane tetracarboxylic dianhydride as tetracarboxylic dianhydride and 2,2'-dimethyl-4,4'-di as diamine 210 g (1.0 mole) of aminobiphenyl was dissolved in a mixed solvent of 370 g of NMP and 3,300 g of γ-butyrolactone, and reacted at 40 ° C for 3 hours to obtain a solid content concentration of 10% by weight and a solution viscosity of 160 mPa ． s polyamine solution. Next, this polyphosphonic acid solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyamic acid (PA-1).

[Synthesis Example 8: Synthesis of polyamidic acid (PA-2)]

Except that the tetracarboxylic dianhydride used was 0.9 mol of pyromellitic dianhydride and 0.1 mol of 1,2,3,4-cyclobutane tetracarboxylic dianhydride, and the diamine was set to p-benzene Except for 0.2 mol of diamine and 4,4'-diamino diphenyl ether, the same method as in Synthesis Example 7 was used to obtain a solid content concentration of 10% by weight and a solution viscosity of 170 mPa. s polyamine solution. Next, this polyphosphonic acid solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyamic acid (PA-2).

[Synthesis Example 9: Synthesis of Polyamic Acid (PA-3)]

7.0 g (0.031 mole) of 2,3,5-tricarboxycyclopentylacetic dianhydride as a tetracarboxylic dianhydride and 13 g of a compound (r1) represented by the following formula (R-1) as a diamine (1 mole with respect to 2,3,5-tricarboxycyclopentylacetic dianhydride, equivalent to 1 mole) Dissolved in 80 g of NMP and reacted at 60 ° C for 4 hours to obtain polyamine 20% by weight solution of acid (PA-3). The solution viscosity of the polyamic acid solution The degree is 2,000mPa. s. The compound (r1) was synthesized in accordance with the description in Japanese Patent Laid-Open No. 2011-100099. Next, this polyphosphonic acid solution was poured into a large amount of excess methanol to precipitate a reaction product. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 40 degreeC for 15 hours, and obtained polyamic acid (PA-3).

[Synthesis Example 10: Synthesis of polyorganosiloxane (APS-1)]

Put a 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (2- (3,4-epoxycyclohexyl) ethyl trimethoxysilane) in a reaction vessel equipped with a stirrer, thermometer, dropping funnel, and reflux cooling tube ECETS) (100.0 g), methyl isobutyl ketone (500 g), and triethylamine (10.0 g) were mixed at room temperature. Next, 100 g of deionized water was added dropwise using a dropping funnel over 30 minutes, and the reaction was performed at 80 ° C. for 6 hours while stirring under reflux. After the reaction, the organic layer was taken out and washed with a 0.2% by weight ammonium nitrate aqueous solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure to obtain a reactive polyorganosiloxane (EPS -1) As a thick transparent liquid. As a result of ¹ H-NMR analysis of this reactive polyorganosiloxane, the chemical shift (δ) = 3.2 ppm was obtained, and an epoxy-based peak was obtained as described in the theoretical strength, and it was confirmed that no epoxy group was generated during the reaction Side effects. The weight average molecular weight Mw of the obtained reactive polyorganosiloxane was 3,500, and the epoxy equivalent was 180 g / mole.

Next, a 200 mL three-necked flask was charged with 10.0 g of reactive polyorganosiloxane (EPS-1), 30.28 g of methyl isobutyl ketone as a solvent, and 4-dodecyloxybenzoic acid as a reactive compound. 3.98 g and 0.10 g of UCAT 18X (trade name, manufactured by San-Apro) was used as a catalyst, and the reaction was carried out by stirring at 100 ° C for 48 hours. After the reaction was completed, ethyl acetate was added to the reaction mixture, and the resulting solution was washed three times with water. The organic layer was dried with magnesium sulfate, and then the solvent was distilled off to obtain a liquid crystal-oriented polyorganosiloxane (APS-1). 9.0g. The weight average molecular weight Mw of the obtained polymer was 9,900.

<Preparation of liquid crystal alignment agent> [Example 1]

To a solution containing polyimide (PI-1) as the polymer (A), NMP and propylene glycol diacetate were added as solvents, and the solvent composition was NMP: PGDAc = 50: 50 (weight ratio), and the solid A solution having a component concentration of 6.5% by weight. This solution was filtered using a filter having a pore size of 1 μm, thereby preparing a liquid crystal alignment agent (S-1). In addition, the liquid crystal alignment agent (S-1) is mainly used for manufacturing a vertical alignment type liquid crystal display element.

<Evaluation of Swellability of Printing Plate>

The swellability (swellability) of the APR plate was evaluated using a solvent for preparing the liquid crystal alignment agent (S-1). The APR plate is a resin plate made of a liquid photosensitive resin that is partially cured by ultraviolet irradiation, and is generally used for a printing plate of a liquid crystal alignment film printer. In the case where the liquid crystal alignment agent is in contact with the APR plate, it is difficult for the APR plate Swelling means that the liquid crystal alignment agent hardly penetrates into the APR plate during printing, and has good printability. The evaluation of the swelling property was performed by immersing the APR plate in a liquid crystal alignment agent for one day, and measuring the weight change of the APR plate before and after immersion. At this time, when the weight increase of the APR plate is less than 4%, the APR plate is difficult to swell and is evaluated as good (○). When the increase amount is 4% or more, the APR plate is easily swelled and evaluated as bad ( ×). The evaluation results are shown in Table 1 below.

<Evaluation of printability>

With respect to the liquid crystal alignment agent prepared as described above, printability (continuous printability) when printing on a substrate was continuously performed was evaluated. Evaluation was performed as follows. First, for the prepared liquid crystal alignment agent (S-1), a liquid crystal alignment film printer (manufactured by Japan Photo Printer (Stock), Angstromer type "S40L-532") was used, and the liquid crystal alignment agent was applied to the anilox roller ( anilox roll) was applied on a transparent electrode surface of a glass substrate with a transparent electrode including an ITO film under a condition of 20 drops (approximately 0.2 g). The application to the substrate was performed 20 times using a new substrate at 1 minute intervals.

Then, the liquid crystal alignment agent was distributed (one way) to the anilox roller at one minute intervals, and the operation of bringing the anilox roller into contact with the printing plate (hereinafter referred to as idling) was performed for a total of 10 minutes. Times (during which no printing is performed on the glass substrate). In addition, this dry operation is an operation performed in order to perform printing of a liquid crystal alignment agent deliberately under severe conditions.

After 10 dry runs, the glass substrate was used for formal printing. In the main printing, after the dry run, 5 substrates are put in at 30 second intervals, and the coating liquid is Each substrate after the crystal alignment agent was heated (pre-baked) at 80 ° C for 1 minute to remove the solvent, and then heated (post-baked) at 200 ° C for 10 minutes to form a coating film having a film thickness of about 80 nm. The printability was evaluated by observing this coating film with a microscope with a magnification of 20 times. The evaluation was performed as follows: the case where no precipitation of the polymer was observed from the first official printing after the dry run was evaluated as excellent (○), and the polymer was observed at the first official print after the dry run. Precipitation, but no polymer precipitation was observed between the five official prints, which was evaluated as good (△), and the polymer precipitation was still observed after five official prints was evaluated as bad ( ×). The evaluation results are shown in Table 1 below. In addition, in the case of a liquid crystal alignment agent having good printability, it has been experimentally found that the precipitation of a polymer is improved (disappeared) between successive substrates. In addition, the number of dry runs was further changed to 15 times, 20 times, and 25 times, and the printability of the liquid crystal alignment agent was evaluated in the same manner as described above. The evaluation results are also shown in Table 1 below.

The symbols of the solvent composition in Table 1 have the following meanings.

a: N-methyl-2-pyrrolidone

b: propylene glycol diacetate

c: γ-butyrolactone

d: N-ethyl-2-pyrrolidone

e: N-pentyl-2-pyrrolidone

f: 1,3-dimethyl-2-imidazolidinone

i: butyl cellosolve

j: propylene glycol ether

k: propylene glycol-n-propyl ether

l: propylene glycol-1-monomethyl ether acetate

m: diacetone alcohol

[Examples 2 to 17 and Comparative Examples 1 to 4]

A liquid crystal alignment agent (S-2) to a liquid crystal were prepared by the same method as in Example 1 except that the type and composition of the polymer (A) and the solvent used were changed to those described in Table 1 above. Alignment agent (S-17) and liquid crystal alignment agent (SR-1) to liquid crystal alignment agent (SR-4). In addition, the swellability and printability of the printing plate were evaluated in the same manner as in Example 1 described above. The results are shown in Table 1 above. In addition, in Table 1, the compounding ratio of a polymer (A) shows the content rate (weight%) of each polymer with respect to 100 weight% of the total amount of the polymers contained in a liquid crystal aligning agent. In addition, the liquid crystal alignment agent (S-2) to the liquid crystal alignment agent (S-14), the liquid crystal alignment agent (SR-1) to the liquid crystal alignment agent (SR-4) are mainly used for manufacturing vertical alignment type liquid crystal display elements, and liquid crystal alignment The agent (S-15) is mainly used for manufacturing TN type liquid crystal display elements, the liquid crystal alignment agent (S-16) is mainly used for manufacturing IPS type liquid crystal display elements, and the liquid crystal alignment agent (S-17) is mainly used for photo-alignment method. Manufacture of a vertical alignment type liquid crystal display element.

As shown in Table 1, compared with the solvents used in the comparative examples, the solvents used in the examples were less likely to swell the APR plate. Therefore, in the liquid crystal alignment agent of the embodiment, In this case, it can be said that the swelling of the printing plate during printing can be suppressed, and the liquid crystal alignment agent can be uniformly applied to the substrate.

In addition, regarding the continuous printability, the liquid crystal alignment agents of the examples were all good. Among them, the compound (p2) was used as a solvent for dissolving the polymer in Examples 3 to 6, and Examples 9 to 17 Medium is particularly good.

Claims (6)

A liquid crystal alignment agent, comprising: a polyamino acid obtained by reacting a tetracarboxylic dianhydride with a diamine; a polyamino acid obtained by subjecting the polyamino acid to dehydration and ring-closing and subjecting it to imidization. At least one polymer (A) in the group consisting of sulfonimine and polyorganosiloxane, wherein the tetracarboxylic dianhydride comprises an alicyclic tetracarboxylic dianhydride; and the compound represented by the following formula (1) Solvent for compound (p1): (In the formula (1), R ¹ and R ³ are each independently a linear or branched monovalent hydrocarbon group having 1 to 3 carbon atoms, and R ² is a linear or branched carbon number 2 to 5 Alkanediyl). The liquid crystal alignment agent according to item 1 of the scope of patent application, wherein the content of the compound (p1) is 5% by weight or more of the total amount of the solvent. The liquid crystal alignment agent according to claim 1 or claim 2, further comprising a compound selected from the group consisting of 1,3-dimethyl-2-imidazolidinone, a compound represented by the following formula (2), and Said at least one compound (p2) in the group consisting of the compound represented by formula (3) as said solvent: (In formula (2), R ⁴ and R ⁵ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a monovalent group containing "-O-" between carbon-carbon bonds of the hydrocarbon group. , R ⁴ and R ⁵ may be bonded to each other to form a ring structure; R ⁶ is an alkyl group having 1 to 6 carbon atoms) (In formula (3), R ⁷ is a monovalent hydrocarbon group having 2 to 5 carbon atoms or a monovalent group containing "-O-" between carbon-carbon bonds in the hydrocarbon group). The liquid crystal alignment agent according to item 3 of the scope of patent application, which comprises at least one selected from the group consisting of polyamic acid and polyimide as the polymer (A), the polyamino acid Is selected from the group consisting of 2,3,5-tricarboxycyclopentylacetic dianhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-dianhydride and Tetracarboxylic dianhydride of at least one of the group consisting of 1,2,3,4-cyclobutane tetracarboxylic dianhydride is obtained by reacting with a diamine. A liquid crystal alignment film is characterized in that it is formed by using the liquid crystal alignment agent according to any one of claims 1 to 4 of the scope of patent application. A liquid crystal display element, comprising the liquid crystal alignment film according to item 5 of the scope of patent application.