TW201915089A - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

The invention relates to a liquid crystal alignment agent and a method for manufacturing the liquid crystal alignment agent. The liquid crystal alignment agent includes a polymer (A), a solvent (B) and an additive (C). The polymer (A) is selected from a group consisting of a polyamide acid polymer and a polyimide polymer. A liquid crystal display element made of the liquid crystal alignment agent of the invention can effectively eliminate charge accumulation even after a light alignment process. The present invention further provides a liquid crystal alignment film formed by the liquid crystal alignment agent, a method for manufacturing the liquid crystal alignment film, and a liquid crystal display element including the liquid crystal alignment film.

Description

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

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element, and more particularly to a liquid crystal alignment agent, which can be used to prepare a liquid crystal display element that has good accumulated charge erasability after photo alignment.

Liquid crystal display elements such as liquid crystal televisions and liquid crystal displays are usually provided with a liquid crystal alignment film that controls the liquid crystal alignment state. At present, the most popular method in the industry is to form a coating film on the electrode substrate by using polyamic acid and / or its imine-imidized polyimide, and then use cotton, nylon, polyester and other cloths for "friction treatment". That is, the coating film on the electrode substrate is wiped in a single direction to prepare the liquid crystal alignment film.

In the alignment process of the liquid crystal alignment film, the rubbing method of the film surface is simple and excellent in productivity, and is an industrially applicable method. However, with the increasing demands for higher performance, higher definition, and larger size of liquid crystal display elements, the effects of scratches, dust, mechanical forces, and static electricity on the surface of the alignment film during friction treatment, as well as the effects on the alignment treatment surface Various problems such as non-uniformity are also more significant.

Known methods that can replace the rubbing treatment include, for example, a photo-alignment method, which imparts alignment energy to a liquid crystal by irradiating polarized ultraviolet rays. For the liquid crystal alignment treatment by the photo-alignment method, as far as the mechanism is concerned, there have been proposed in the literature to use a method such as a photo-isomerization reaction, a photo-crosslinking reaction, or a photo-decomposition reaction. In addition, other literatures have proposed the use of polyfluorene imine films having an alicyclic structure such as a cyclobutane ring in a photo-alignment method. The alignment film for photo-alignment using the polyfluorene imide can have high heat resistance, so its applicability is highly expected.

As a non-friction alignment treatment method, the photo-alignment method not only has the advantage of being easy to produce in a simple process in industry, but also for IPS-driven or FFS-driven liquid crystal display elements, compared to the friction-treated liquid crystal alignment film. The liquid crystal display element of the liquid crystal alignment film obtained by the above-mentioned light alignment method is expected to have improved characteristics such as contrast and viewing angle, as well as performance. Therefore, such a liquid crystal alignment processing method has attracted much attention.

However, when the liquid crystal alignment film prepared by the photo-alignment method is applied to a liquid crystal display element, there is still a problem of poor charge elimination after the photo alignment, that is, in the liquid crystal display element prepared after the liquid crystal alignment film is illuminated. The residual charge accumulated by the AC drive is slowly eliminated, causing the residual charge to be too high, which in turn causes the problem of afterimages. It can be known from the foregoing that in order to meet the requirements of current photo-alignment IPS-type liquid crystal display manufacturers, a liquid crystal alignment agent is provided. The liquid crystal display element produced by the device can still maintain good accumulated charge elimination after photo-alignment. The goal of hard research.

The present invention obtains a liquid crystal alignment agent by providing components such as special polymers, additives, and the like. The liquid crystal display element formed by the liquid crystal alignment agent still has the advantage of good charge storage elimination after photo alignment.

Therefore, the present invention provides a liquid crystal alignment agent, comprising: a polymer (A) selected from the group consisting of a polyamic acid resin and a polyimide resin; a solvent (B); and an additive (C); Object (A) includes a structure represented by the following formula (I): In formula (I), in formula (I), Z _{1 is} each and independently an ether bond or an ester bond; R _{1 is} each and independently a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; each of R _{2 is} And is independently a halogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbon atoms, and a carbon number is An alkoxy group of 1 to 9, a cycloalkyl group having 3 to 12 carbons, or an aryl group having 6 to 12 carbons; m is an integer from 0 to 4; and * ^a represents a bonding point; additive (C) Containing a carboxylic acid compound (c-1) represented by the following formula (III): Formula (III) In formula (III), R ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms; R ² to R ⁶ are each independently a hydrogen atom, a hydroxyl group, -X-COOH, and a carbon number of 1 Alkyl to 6, alkenyl with 2 to 6 carbons, alkynyl with 2 to 6 carbons, cycloalkyl with 3 to 7 carbons, aryl with 6 to 12 carbons, COOR ⁷ , OR ⁸ or two adjacent R ² to R ⁶ groups together form a ring; X is a single bond or an alkylene group having 1 to 6 carbons; and R ⁷ and R ⁸ are each 1 to 20 carbons alkyl.

The present invention further provides a liquid crystal alignment film, which is formed by the aforementioned liquid crystal alignment agent.

The present invention also provides a liquid crystal display device including the aforementioned liquid crystal alignment film.

The present invention also provides a method for manufacturing a liquid crystal alignment agent, comprising: reacting a tetracarboxylic dianhydride component (a) and a diamine component (b) to obtain a polymer (A), wherein the diamine component ( b) containing a diamine compound (b-1) represented by the following formula (I '): Formula (I ') In Formula (I'), Z _{1 is} each and independently an ether bond or an ester bond; R _{1 is} each and independently a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; R ₂ are each independently a halogen atom, an alkyl group having 1 to 4 carbons or an alkoxy group having 1 to 4 carbons; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbons, carbon An alkoxy group of 1 to 9, a cycloalkyl group of 3 to 12 carbons, an aryl group of 6 to 12 carbons; and m is an integer of 0 to 4; providing a solvent (B); providing an additive (C ), Which includes the carboxylic acid compound (c-1) represented by the following formula (III): Formula (III) In formula (III), R ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms; R ² to R ⁶ are each independently a hydrogen atom, a hydroxyl group, -X-COOH, and a carbon number of 1 Alkyl to 6, alkenyl with 2 to 6 carbons, alkynyl with 2 to 6 carbons, cycloalkyl with 3 to 7 carbons, aryl with 6 to 12 carbons, COOR ⁷ , OR ⁸ or two adjacent R ² to R ⁶ groups together form a ring; X is a single bond or an alkylene group having 1 to 6 carbons; and R ⁷ and R ⁸ are each 1 to 20 carbons Alkyl; and mixed polymer (A), solvent (B) and additive (C).

The invention further provides a method for manufacturing a liquid crystal alignment film, comprising forming the liquid crystal alignment film by using the liquid crystal alignment agent prepared by the method for manufacturing a liquid crystal alignment agent.

The present invention also provides a method for manufacturing a liquid crystal display element, including forming a liquid crystal display element using the liquid crystal alignment film obtained by the method for manufacturing a liquid crystal alignment film.

The invention provides a liquid crystal alignment agent, comprising: a polymer (A) selected from the group consisting of a polyamic acid resin and a polyimide resin; a solvent (B); and an additive (C); wherein, the polymer (A) A) contains the structure shown by the following formula (I): In formula (I), in formula (I), Z _{1 is} each and independently an ether bond or an ester bond; R _{1 is} each and independently a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; each of R _{2 is} And is independently a halogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbon atoms, and a carbon number is An alkoxy group of 1 to 9, a cycloalkyl group having 3 to 12 carbon atoms, and an aryl group having 6 to 12 carbon atoms; m is an integer from 0 to 4; and * ^a represents a bond; the additive (C) contains The carboxylic acid compound (c-1) represented by the following formula (III): Formula (III) In formula (III), R ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms; R ² to R ⁶ are each independently a hydrogen atom, a hydroxyl group, -X-COOH, and a carbon number of 1 Alkyl to 6, alkenyl with 2 to 6 carbons, alkynyl with 2 to 6 carbons, cycloalkyl with 3 to 7 carbons, aryl with 6 to 12 carbons, COOR ⁷ , OR OR ⁸ or two adjacent R ² to R ⁶ groups together form a ring; X is a single bond or an alkylene group having 1 to 6 carbons; and R ⁷ and R ⁸ are each 1 to 20 carbons Alkyl.

The invention provides a method for manufacturing a liquid crystal alignment agent, comprising: reacting a tetracarboxylic dianhydride component (a) and a diamine component (b) to obtain a polymer (A), wherein the diamine component (b ) Contains a diamine compound (b-1) represented by the following formula (I '): Formula (I ') In Formula (I'), Z _{1 is} each and independently an ether bond or an ester bond; R _{1 is} each and independently a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; R ₂ are each independently a halogen atom, an alkyl group having 1 to 4 carbons or an alkoxy group having 1 to 4 carbons; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbons, carbon An alkoxy group having a number of 1 to 9, a cycloalkyl group having a carbon number of 3 to 12, or an aryl group having a carbon number of 6 to 12; and m is an integer of 0 to 4; providing a solvent (B); providing an additive ( C) comprising a carboxylic acid compound (c-1) represented by the following formula (III): Formula (III) In formula (III), R ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms; R ² to R ⁶ are each independently a hydrogen atom, a hydroxyl group, -X-COOH, and a carbon number of 1 Alkyl to 6, alkenyl with 2 to 6 carbons, alkynyl with 2 to 6 carbons, cycloalkyl with 3 to 7 carbons, aryl with 6 to 12 carbons, COOR ⁷ , OR OR ⁸ or two adjacent R ² to R ⁶ groups together form a ring; X is a single bond or an alkylene group having 1 to 6 carbons; and R ⁷ and R ⁸ are each 1 to 20 carbons Alkyl group; and mixed polymer (A), solvent (B) and additive (C).

Hereinafter, each component of the liquid crystal alignment agent used in the present invention will be described in detail.

The polymer (A) of the present invention includes a structure represented by the following formula (I): Formula (I) In formula (I), Z _{1 is} each independently an ether bond or an ester bond; R _{1 is} each a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; R ₂ Each and independently a halogen atom, an alkyl group having 1 to 4 carbons or an alkoxy group having 1 to 4 carbons; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbons, and a carbon number Is an alkoxy group of 1 to 9, a cycloalkyl group of 3 to 12 carbons, or an aryl group of 6 to 12 carbons; m is an integer of 0 to 4; and * ^a represents a bond.

Preferably, Z ₁ of the structure represented by formula (I) is an ether bond.

The polymer (A) can be prepared by reacting a tetracarboxylic dianhydride component (a) and a diamine component (b).

Preferable specific examples of the above-mentioned polymer (A) are a polyfluorinated acid polymer, a polyfluorinated imine polymer, a polyfluorinated block copolymer, or a combination thereof. Among them, preferable specific examples of the polyimide-based block copolymer are a polyimide block copolymer, a polyimide block copolymer, and a polyimide-polyimide block copolymer. Polymer, or a combination of them.

The tetracarboxylic dianhydride component (a) includes a tetracarboxylic dianhydride compound (a-1) having a cyclobutane ring represented by the following formula (II): Formula (II) In Formula (II), R ₄ , R ₅ , R _6, and R ₇ are each independently a hydrogen atom, an alkyl group having 2 to 6 carbon atoms, and R ₄ , R ₅ , R _6, and R ₇ can be the same or different.

When R ₄ , R ₅ , R ₆ and R _{7 have} a structure with large steric hindrance, the alignment of the liquid crystal will be poor. Therefore, R ₄ , R ₅ , R _6, and R _{7 are} preferably a hydrogen atom, a methyl group, or an ethyl group, and more preferably a hydrogen atom or a methyl group.

Specific examples of the tetracarboxylic dianhydride compound (a-1) having a cyclobutane ring represented by the above formula (II) include the following formulae (II-1) to (II-5); among them, the liquid crystal alignment is considered The formula (II-1) and formula (II-2) are preferred, and the formula (II-2) is more preferred. Formula (II-1) Formula (II-2) Formula (II-3) Formula (II-4) Formula (II-5)

Based on the total use amount of the tetracarboxylic dianhydride component (a) is 100 mol, and the use amount of the tetracarboxylic dianhydride compound (a-1) is 20 to 100 mol, preferably 30 to 90 mol, Of course, 40 to 80 mol is more preferred.

The tetracarboxylic dianhydride component (a) may further include other tetracarboxylic dianhydride compounds (a-2), and preferred specific examples thereof are (1) an aliphatic tetracarboxylic dianhydride compound, and (2) an alicyclic ring. Group tetracarboxylic dianhydride compounds, (3) aromatic tetracarboxylic dianhydride compounds, (4) tetracarboxylic dianhydride compounds having formulas (a-2-1) to (a-2-6), and the like.

(1) The aliphatic tetracarboxylic dianhydride compound according to the present invention includes, but is not limited to, an aliphatic tetracarboxylic dianhydride compound such as ethanetetracarboxylic dianhydride or butanetetracarboxylic dianhydride.

(2) The alicyclic tetracarboxylic dianhydride compound according to the present invention includes, but is not limited to, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2-dimethyl-1,2,3 , 4-cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,3-dichloro-1,2,3, 4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane Alkanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic dianhydride, cis-3,7-di Butylcycloheptyl-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride or bicyclo [2.2.2]- Alicyclic tetracarboxylic dianhydride compounds such as oct-7-ene-2,3,5,6-tetracarboxylic dianhydride.

Specific examples of the (3) aromatic tetracarboxylic dianhydride compound according to the present invention may include, but are not limited to, 3,4-dicarboxyl-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, benzene Mesoteric acid dianhydride, 2,2 ', 3,3'-benzophenone tetracarboxylic dianhydride, 3,3', 4,4'-benzophenone tetracarboxylic dianhydride, 3,3 ', 4,4'-Biphenylphosphonium tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3' -4,4'-diphenylethane tetracarboxylic dianhydride, 3,3 ', 4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3', 4,4'- Tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride, 2,3,3 ', 4'-diphenyl ether tetracarboxylic dianhydride, 3,3', 4 , 4'-diphenyl ether tetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydride, 2,3,3 ', 4'-diphenylsulfide Ether tetracarboxylic dianhydride, 3,3 ', 4,4'-diphenyl sulfide tetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylarsine dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ', 4,4'-perfluoroisopropylidene diphthalic dianhydride, 2,2 ', 3,3'-Diphenyltetracarboxylic dianhydride, 2,3,3', 4'-diphenyltetracarboxylic dianhydride, 3,3 ', 4,4'-diphenyltetracarboxylic acid Acid dianhydride, bis (phthalic acid) benzene Oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4'-diphenyl ether dianhydride, bis (triphenylphthalic acid) -4,4'-diphenylmethane dianhydride, ethylene glycol-bis (anhydrotrimellitic acid ester), propylene glycol -Bis (dehydrated trimellitate), 1,4-butanediol-bis (dehydrated trimellitate), 1,6-hexanediol-bis (dehydrated trimellitate), 1,8 -Octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis (anhydrotrimellitate), 2,3,4,5-tetrahydrofuran tetracarboxylate 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-5-methyl-5- (tetrahydro-2,5-dioxo-3-furyl)- Naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5-ethyl-5- (tetrahydro-2,5-di Pendantoxy-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-7-methyl-5 -(Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b -Hexahydro-7-ethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1 , 2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo- 3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-ethyl-5- (tetrahydro -2,5-dioxo-3-furyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro- 5,8-dimethyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 5- (2,5-dioxotetrahydrofuranyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride and the like.

The tetracarboxylic dianhydride compounds having the formulae (a-2-1) to (a-2-6) according to (4) of the present invention are detailed as follows: (A-2-1) Formula (a-2-2) (A-2-3) (A-2-4) Formula (a-2-5) In formula (a-2-5), A ₁ represents a divalent group containing an aromatic ring; r represents an integer of 1 to 2; A ₂ and A ₃ may be the same or different, and It may represent a hydrogen atom or an alkyl group, respectively.

Preferably, the tetracarboxylic dianhydride compound represented by the formula (a-2-5) may be selected from the following formulae (a-2-5-1) to (a-2-5-3) Compounds: Formula (a-2-5-1) Formula (a-2-5-2) Formula (a-2-5-3) Formula (a-2-6) In formula (a-2-6), A ₄ represents a divalent group containing an aromatic ring; A ₅ and A ₆ may be the same or different, and each represents a hydrogen atom or an alkyl group. . Preferably, the tetracarboxylic dianhydride compound represented by the formula (a-2-6) may be selected from the compounds represented by the following formula (a-2-6-1): Formula (a-2-6-1)

The other tetracarboxylic dianhydride compounds (a-2) described above may be used alone or in combination.

The total amount of the tetracarboxylic dianhydride component (a) is 100 mol, and the amount of the other tetracarboxylic dianhydride compound (a-2) is 0 to 80 mol, preferably 10 to 70 mol. Of course, 20 to 60 moles is better.

Based on the diamine component (b) used in an amount of 100 moles, the tetracarboxylic dianhydride component (a) used in an amount of 20 to 200 moles; preferably 30 to 120 moles.

The diamine component (b) comprises a diamine compound (b-1) represented by the following formula (I '): Formula (I ') In Formula (I'), Z _{1 is} each and independently an ether bond or an ester bond; R _{1 is} each and independently a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; R _{2 is} each independently a halogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbon atoms, An alkoxy group having 1 to 9 carbons, a cycloalkyl group having 3 to 12 carbons, an aryl group having 6 to 12 carbons; and m is an integer of 0 to 4.

Preferably, Z1 of the structure represented by the formula (I ') is an ether bond.

Specifically, specific examples of the diamine compound (b-1) may include compounds represented by the following formulae (I'-1) to (I'-26): Formula (I'-1) Formula (I'-2) Formula (I'-3) Formula (I'-4) Formula (I'-5) Formula (I'-6) Formula (I'-7) Formula (I'-8) Formula (I'-9) Formula (I'-10) Formula (I'-11) Formula (I'-12) Formula (I'-13) Formula (I'-14) Formula (I'-15) Formula (I'-16) Formula (I'-17) Formula (I'-18) Formula (I'-19) Formula (I'-20) Formula (I'-21) Formula (I'-22) Formula (I'-23) Formula (I'-24) Formula (I'-25) Formula (I'-26)

The above-mentioned diamine compound (b-1) can be synthesized by a standard method using appropriate organic chemistry, and a synthesis method of the diamine compound (b-1) of the present invention is exemplified below. However, it should be particularly noted that the diol compound and the diacid compound used below, and nitrobenzidine chloride and fluoronitrobenzene may be arbitrarily combined, and the present invention is not limited to the following examples.

In one embodiment, the method for synthesizing the diamine compound (b-1) of the above formula (I'-1) to formula (I'-16) is as follows: First, 1 equivalent of a diol compound and 2 equivalents of 4-fluoronitrobenzene (4-fluoronitrobenzene) is reacted to form a dinitro compound. Next, the aforementioned nitro group is reduced to an amine group with an appropriate reducing agent, and the diamine compound (b-1) of the above formula (I'-1) to (I'-16) can be synthesized. For example, by using 1,3-dioxane-5,5-dimethanol as the diol compound, a diamine compound represented by the formula (I'-1) can be obtained. If 1,3-dioxane-5,5-dimethanol is replaced with 2-methyl-1,3-dioxane-5,5-dimethanol, the formula (I'-2) can be obtained. Diamine compound shown. In another example, if 2-butyl-1,3-dioxane-5,5-dimethanol is used as the diol compound, and the aforementioned 4-fluoronitrobenzene is replaced with 3-fluoronitrobenzene , A diamine compound having an amine group represented by formula (I'-4) in the meta position can be prepared.

In one embodiment, the method for synthesizing the diamine compound (b-1) of the formula (I'-17) to the formula (I'-23) is as follows: First, 1 equivalent of a diol compound and 2 equivalents of 4-nitrobenzoyl chloride is reacted to form a dinitro compound. Next, the aforementioned nitro group is reduced to an amine group with an appropriate reducing agent, and the diamine compound (b-1) of the aforementioned formula (I'-17) to (I'-23) can be synthesized. For example, if 2,2-dimethyl-1,3-dioxane-5,5-dimethanol is used as the diol compound, a diamine represented by the formula (I'-17) can be prepared. Compound. If 2,2-dimethyl-1,3-dioxane-5,5-dimethanol is replaced with 2-ethyl-1,3-dioxane-5,5-dimethanol, it can be obtained A diamine compound represented by the formula (I'-18). On the other hand, if 2-benzyl-1,3-dioxane-5,5-dimethanol is used as the diol compound, and 4-nitrobenzidine chloride is replaced with 3-nitrobenzidine Chlorine can be used to prepare a diamine compound with the amine group of formula (I'-22) in the meta position.

In one embodiment, the method for synthesizing the diamine compound (b-1) of the above formula (I'-24) to formula (I'-26) is as follows: First, 1 equivalent of a diacid compound and 2 equivalents of 4-Fluoronitrobenzene reacts to form a dinitro compound. Next, by reducing the aforementioned nitro group to an amine group, the diamine compound (b-1) of the aforementioned formula (I'-24) to (I'-26) can be synthesized. For example, using 2,2 '-(1,3-dioxane-5,5-diyl) diacetic acid as the diacid compound, a diamine represented by the formula (I'-24) can be prepared Compound. If 2,2 '-(1,3-dioxane-5,5-diyl) diacetic acid is replaced with 2-heptyl-1,3-dioxane-5,5-dicarboxylic acid, then A diamine compound represented by the formula (I'-25) was obtained. On the other hand, if 2-methyl-1,3-dioxane-5,5-dicarboxylic acid is used as the diacid compound, and 4-fluoronitrobenzene is replaced with 3-fluoronitrobenzene, then A diamine compound having an amine group represented by formula (I'-26) in the meta position is obtained.

In an embodiment, the aforementioned diol compound may include, but is not limited to, 1,3-dioxane-5,5-dimethanol, 2-methyl-1,3-dioxane-5,5- Dimethyl alcohol, 2-propyl-1,3-dioxane-5,5-dimethanol, 2-butyl-1,3-dioxane-5,5-dimethanol, 2-hexyl-1,3 -Dioxane-5,5-dimethanol, 2-isopropyl-1,3-dioxane-5,5-dimethanol, 2-nonyl-1,3-dioxane-5,5- Dimethyl alcohol, 1,3-dioxane-5-methanol-5-n-propanol, 2-ethoxy-1,3-dioxane-5,5 dimethanol, 2- (chloromethyl) -1 , 3-dioxane-5,5-dimethanol, 2-phenyl-1,3-dioxane-5,5-dimethanol, 2-phenethyl-1,3-dioxane-5, 5-dimethanol, 2- (naphthalene-2-yl) -1,3-dioxane-5,5-dimethanol, 2-([1,1'-bis (cyclohexyl)]-4-yl) -1,3-dioxane-5,5-dimethanol, 2-phenyl-1,3-dioxane-5,5-diol, 2-([1,1'-diphenyl]- 4-yl) -1,3-dioxane-5,5-dimethanol, 2,2-dimethyl-1,3-dioxane-5,5-dimethanol, 2-ethyl-1, 3-dioxane-5,5-dimethanol, 2-pentyl-1,3-dioxane-5,5-dimethanol, 2-methyl-1,3-dioxane-5,5- Diethanol, 2-propoxy-1,3-dioxane-5,5-dimethanol, 2-benzyl-1,3-dioxane-5,5-dimethanol, or 2- (p- Toluene)- 1,3-dioxane-5,5-dimethanol.

In an embodiment, the aforementioned diacid compound may include, but is not limited to, 2,2 '-(1,3-dioxane-5,5-diyl) diacetic acid, 2-heptyl-1,3 -Dioxane-5,5-dicarboxylic acid or 2-methyl-1,3-dioxane-5,5-dicarboxylic acid.

In one embodiment, the aforementioned reducing agents include, but are not limited to, zinc, hydrazine, hydrazine hydrate, hydrazine sulfate, hydrazine carbonate, and hydrazine hydrochloride.

Based on the total usage of the diamine component (b) is 100 mol, and the usage of the diamine compound (b-1) is 2 to 20 mol, preferably 3 to 15 mol, and then 4 to 10 mol. Ears are better. If the diamine compound (b-1) is not used, the formed liquid crystal display element has poor stored charge erasability after photo-alignment.

In particular, for the structure represented by the formula (I) included in the polymer (A) of the present invention, reference may be made to the content of the diamine compound (b-1). In addition, the structure of the formula (I) is that the diamine compound (b-1) of the formula (I ') and the tetracarboxylic dianhydride component (a) are dehydrated and condensed to form a amine bond (that is, ^a Representative of the key junction).

In a preferred example, the structure represented by formula (I) and Z ₁ in the diamine compound (b-1) represented by formula (I ') are ether bonds, so that the obtained liquid crystal display element After photo-alignment, it can have better accumulated charge elimination.

The diamine component (b) may further include other diamine compounds (b-2), which may include, but is not limited to, 1,2-diaminoethane, 1,3-diaminopropane, 1,4- Diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9- Diaminononane, 1,10-diaminodecane, 4,4'-diaminoheptane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamine -2,5-dimethylhexane, 1,7-diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1, 7-diamino-3-methylheptane, 1,9-diamino-5-methylnonane, 2,11-diaminododecane, 1,12-diaminooctadecane, 1,2-bis (3-aminopropyloxy) ethane, 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexyl Amine, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, isophorone diamine, tetrahydrodicyclopentadiene diamine, tricyclic (6.2.1.1. 02,7) -Undecenyldimethyldiamine, 4,4'-methylenebis (cyclohexylamine), 4,4'-diaminodiphenylmethane, 4,4'-diamine Diphenylethane, 4,4'-diaminodiphenylphosphonium, 4,4'-diaminobenzidineaniline, 4,4'- Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 5-amino-1- (4'-aminophenyl) -1,3 , 3-trimethylhydroindene, 6-amino-1- (4'-aminophenyl) -1,3,3-trimethylhydroindene, hexahydro-4,7-methyl bridgedindene Dimethylenediamine, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2 -Bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4 -Aminophenyl) hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] fluorene, 1,4-bis (4-aminophenoxy) cyclohexane, 1,5-bis (4-aminophenoxymethylene) adamantane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) Benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 9,10-bis (4-aminophenyl) Anthracene [9,10-bis (4-aminophenyl) anthracene], 2,7-diaminofluorene, 9,9-bis (4-aminophenyl) fluorene, 4,4'-methylene-bis ( 2-chloroaniline), 4,4 '-(p-phenylene isopropylidene) bisaniline, 4,4'-(m-phenylene isopropylidene) bisaniline, 2,2'-bis [4- (4-Amino-2-trifluoromethylphenoxy) phenyl] hexa Propane, 4,4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octafluorobiphenyl, 5- [4- (4-n-pentylcyclohexyl) cyclohexyl] Phenylmethylene-1,3-diaminobenzene {5- [4- (4-n-pentylcyclohexyl) cyclohexyl] phenylmethylene-1,3-diaminobenzene}, 1,1-bis [4- (4-amine Phenylphenoxy) phenyl] -4- (4-ethylphenyl) cyclohexane {1,1-bis [4- (4-aminophenoxy) phenyl] -4- (4-ethyl phenyl) cyclohexane} or Other diamine compounds represented by the following formulae (b-2-1) to (b-2-29).

Formula (b-2-1) is as follows: Formula (b-2-1) In formula (b-2-1), X ₆ represents , , , , or And X ₇ represents a cyclic structure containing a steroid group, a trifluoromethyl group, a fluoro group, an alkyl group having 2 to 30 carbon atoms or a nitrogen atom-containing cyclic structure derived from pyridine, pyrimidine, triazine, piperidine, and piperazine. Monovalent group.

The other diamine compounds represented by the above formula (b-2-1) may preferably be 2,4-diaminophenyl ethyl formate, 3,5-diaminobenzene 3,5-diaminophenyl ethyl formate, 2,4-diaminophenyl propyl formate, 3,5-diaminophenyl propyl formate, (3 , 5-diaminophenyl propyl formate), 1-dodecoxy-2,4-diamino-benzene, 1-hexadecyloxy-2,4- 1-hexadecoxy-2,4-diaminobenzene, 1-octadecoxy-2,4-diaminobenzene or the following formula (b-2 -1-1) to other diamine compounds represented by formula (b-2-1-6): Formula (b-2-1-1) Formula (b-2-1-2) Formula (b-2-1-3) Formula (b-2-1-4) Formula (b-2-1-5) Formula (b-2-1-6)

Formula (b-2-2) is as follows: Formula (b-2-2) In formula (b-2-2), X ₈ represents , , , , or X ₉ and X ₁₀ represent an aliphatic ring, an aromatic ring or a heterocyclic group, and X ₁₁ represents an alkyl group having 3 to 18 carbon atoms, an alkoxy group having 3 to 18 carbon atoms, and carbon number It is a fluoroalkyl group of 1 to 5, a fluoroalkoxy group of 1 to 5 carbon atoms, a cyano group or a halogen atom.

The other diamine compounds represented by the above formula (b-2-2) may preferably be diamine compounds represented by the following formula (b-2-2-1) to formula (b-2-2-13): (b-2-2-1) (b-2-2-2) (b-2-2-3) (b-2-2-4) (b-2-2-5) (b-2-2-6) (b-2-2-7) (b-2-2-8) (b-2-2-9) (b-2-2-10) (b-2-2-11) (b-2-2-12) (b-2-2-13) In the formulae (b-2-2-10) to (b-2-2-13), s may represent an integer of 3 to 12.

Formula (b-2-3) is as follows: Formula (b-2-3) In formula (b-2-3), X ₁₂ represents a hydrogen atom, a fluorenyl group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, and 1 to 5 carbon atoms. Alkoxy or halogen. X ₁₃ is an integer from 1 to 3. When X _{13 is} greater than 1, the plurality of X ₁₂ may be the same or different.

The diamine compound represented by the formula (b-2-3) is preferably selected from (1) X13 is 1: p-diaminebenzene, m-diaminebenzene, o-diaminebenzene, or 2,5- Diamine toluene, etc .; (2) X13 is 2: 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl -4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamine Biphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 2,2 ', 5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2' -Dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl or 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, etc .; (3) X13 is 3: 1,4-bis (4'-aminophenyl) benzene and the like, more preferably selected from p-diaminebenzene, 2,5-diaminetoluene, 4,4'-di Aminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl or 1,4-bis (4'-aminophenyl) benzene.

Formula (b-2-4) is as follows: Formula (b-2-4) In formula (b-2-4), X ₁₄ represents an integer of 1 to 5. The formula (b-2-4) is preferably selected from 4,4'-diaminodiphenyl sulfide.

Formula (b-2-5) is as follows: Formula (b-2-5) In formula (b-2-5), X ₁₅ and X ₁₇ may be the same or different, and each represents a divalent organic group, and X ₁₆ represents a derivative derived from pyridine, pyrimidine, triazine, A divalent group containing a nitrogen atom ring structure such as piperidine and piperazine.

Formula (b-2-6) is as follows: Formula (b-2-6) In formula (b-2-6), X ₁₈ , X ₁₉ , X ₂₀ and X ₂₁ may be the same or different, and may represent a hydrocarbon group having 1 to 12 carbon atoms. X ₂₂ represents an integer from 1 to 3, and X ₂₃ represents an integer from 1 to 20.

Formula (b-2-7) is as follows: Formula (b-2-7) In formula (b-2-7), X ₂₄ represents Or cyclohexyl, X ₂₅ represents X ₂₆ represents a phenylene or a cyclohexane group, and X ₂₇ represents a hydrogen atom or a heptyl group.

The diamine compound represented by the above formula (b-2-7) is preferably selected from the diamine compounds represented by the following formula (b-2-7-1) and formula (b-2-7-2): Formula (b-2-7-1) Formula (b-2-7-2)

Other diamine compounds represented by formula (b-2-8) to formula (b-2-29) are as follows: Formula (b-2-8) Formula (b-2-9) Formula (b-2-10) Formula (b-2-11) Formula (b-2-12) Formula (b-2-13) Formula (b-2-14) Formula (b-2-15) Formula (b-2-16) Formula (b-2-17) Formula (b-2-18) Formula (b-2-19) Formula (b-2-20) Formula (b-2-21) Formula (b-2-22) Formula (b-2-23) Formula (b-2-24) Formula (b-2-25) Formula (b-2-26) Formula (b-2-27) Formula (b-2-28) Formula (b-2-29) In formulas (b-2-16) to (b-2-19), X ₂₈ is an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms. Is better. In formulae (b-2-20) to (b-2-24), X _{29 is} preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

Other diamine compounds (b-2) may preferably include, but not limited to, 1,2-diaminoethane, 4,4'-diaminodicyclohexylmethane, 4,4'-diaminodiphenyl Methane, 4,4'-diaminodiphenyl ether, 5- [4- (4-n-pentylcyclohexyl) cyclohexyl] phenylmethylene-1,3-diaminobenzene, 1, 1-bis [4- (4-aminophenoxy) phenyl] -4- (4-ethylphenyl) cyclohexane, ethyl 2,4-diaminophenylformate, p-diamine Benzene, m-diamine benzene, o-diamine benzene, formula (b-2-1-1), formula (b-2-1-2), formula (b-2-1-5), formula (b -2-2-1), (b-2-2-11), (b-2-7-1), (b-2-25), or (b-2-28) Compound.

The aforementioned other diamine compounds (b-2) may be used alone or in combination.

Based on the total amount of diamine component (b) used is 100 moles, the amount of other diamine compounds (b-2) used is 80 to 98 moles, preferably 85 to 97 moles, and then 90 to 96 Mor is better.

The preparation of the polyamic acid polymer according to the present invention may be a general method. Preferably, the preparation method of the polyamino acid polymer includes the following steps: the tetracarboxylic dianhydride component (a) and A mixture of the amine component (b) is dissolved in a solvent, and a polycondensation reaction is performed at a temperature of 0 ° C to 100 ° C for 1 hour to 24 hours. Then, the above reaction solution is subjected to reduced pressure distillation by an evaporator. To obtain a polyamine polymer, or to pour the above reaction solution into a large amount of a lean solvent to obtain a precipitate, and then subject the precipitate to drying treatment under a reduced pressure drying method to obtain polyamine Acid polymer.

The solvent used in the polycondensation reaction may be the same as or different from the solvent in the liquid crystal alignment agent described below, and the solvent used in the polycondensation reaction is not particularly limited as long as it can dissolve the reactant and the product. Preferably, the solvent includes, but is not limited to (1) an aprotic polar solvent, for example: N-methyl-2-pyrrolidinone (NMP), N, N-dimethylacetamide , Aprotic polar solvents such as N, N-dimethylformamide, dimethylmethylene sulfoxide, γ-butyrolactone, tetramethylurea or hexamethyl phosphate triamine; (2) phenolic solvents, For example: m-cresol, xylenol, phenol or halogenated phenols. The use amount based on the mixture is 100 parts by weight, and the use amount of the solvent used in the polycondensation reaction is preferably 200 parts by weight to 2000 parts by weight, and more preferably 300 parts by weight to 1800 parts by weight.

In particular, in the polycondensation reaction, an appropriate amount of a lean solvent can be used in combination with the solvent, wherein the lean solvent does not cause precipitation of the polyamine polymer. Lean solvents can be used singly or in combination, and they include but are not limited to (1) alcohols, such as: methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butane Alcohols or alcohols such as triethylene glycol; (2) ketones, such as: ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone; (3) esters, such as: Esters of methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, diethyl malonate, or ethylene glycol ethyl ether acetate; (4) ethers, such as diethyl ether, Ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, or diethylene glycol dimethyl ether Ethers such as alkyl ethers; (5) halogenated hydrocarbons, such as: dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, or o-dichloro Halogenated hydrocarbons such as benzene; (6) hydrocarbons, for example: hydrocarbons such as tetrahydrofuran, hexane, heptane, octane, benzene, toluene or xylene, or any combination of the above solvents. Based on the used amount of the diamine component (b) being 100 parts by weight, the use amount of the lean solvent is preferably 0 to 60 parts by weight, and more preferably 0 to 50 parts by weight.

The preparation of the polyimide polymer according to the present invention may be a general method. Preferably, the preparation method of the polyimide polymer firstly dissolves a mixture in a solution, wherein the mixture includes a tetracarboxylic dianhydride component. (a) and a diamine component (b), and a polymerization reaction is performed to form a polyamino acid polymer. Next, in the presence of a dehydrating agent and a catalyst, further heating is performed, and a dehydration ring-closing reaction is performed, so that the amino acid functional group in the polyfluorinated polymer is converted into a fluorene imine functional group (i.e. Amination) to obtain a polyfluorene imine polymer.

The solvent used in the dehydration ring-closing reaction may be the same as the solvent in the liquid crystal alignment agent described below, so it will not be repeated here. The use amount of the polyamic acid polymer is 100 parts by weight, and the use amount of the solvent used in the dehydration ring-closure reaction is preferably 200 parts by weight to 2000 parts by weight, and more preferably 300 parts by weight to 1800 parts by weight.

In order to obtain a better degree of amidine imidization of the polyamic acid polymer, the operating temperature of the dehydration ring-closing reaction is preferably 40 ° C to 200 ° C, and more preferably 40 ° C to 150 ° C. If the operating temperature of the dehydration ring-closing reaction is lower than 40 ° C, the imidization reaction is not complete, and the degree of imidization of the polyacid polymer is reduced. However, if the operating temperature of the dehydration ring-closing reaction is higher than 200 ° C., the weight average molecular weight of the obtained polyfluorene imine polymer is low.

The dehydrating agent used in the dehydration ring-closure reaction may be selected from acid anhydride compounds, and specific examples thereof include acid anhydride compounds such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride. Based on 1 mole of polyamic acid polymer, the amount of dehydrating agent used is 0.01 to 20 moles. The catalyst used in the dehydration ring-closing reaction can be selected from (1) pyridine compounds, such as: pyridine compounds such as pyridine, trimethylpyridine, or lutidine; (2) tertiary amine compounds, such as: Tertiary amines such as triethylamine. Based on the amount of dehydrating agent used is 1 mole, the amount of catalyst used is 0.5 to 10 moles.

Preferred specific examples of the polyimide-based block copolymer according to the present invention are a polyimide block copolymer, a polyimide block copolymer, and a polyimide-polyimide block copolymer. Block copolymers, or any combination of these.

The preparation of the polyfluorene-based block copolymer according to the present invention may be a general method. Preferably, the preparation method of the polyfluorene-based block copolymer is firstly dissolved in a solvent, and A polycondensation reaction is performed, wherein the starting material includes at least one polyfluorinated acid polymer and / or at least one polyimide polymer described above, and may further include a tetracarboxylic dianhydride component (a ) And diamine component (b).

The tetracarboxylic dianhydride component (a) and the diamine component (b) in the starting material are the same as the tetracarboxylic dianhydride component (a) and The diamine component (b) is the same, and the solvent used in the polycondensation reaction may be the same as the solvent in the liquid crystal alignment agent described below, which is not repeated here.

The amount of the solvent used in the polycondensation reaction is preferably 200 to 2000 parts by weight, and more preferably 300 to 1800 parts by weight based on the use amount of the starting material. The operating temperature of the polycondensation reaction is preferably 0 ° C to 200 ° C, and more preferably 0 ° C to 100 ° C.

Preferably, the starting material includes, but is not limited to, (1) two polyimide polymers having different terminal groups and different structures; (2) two polyimide polymers having different terminal groups and different structures Polymers; (3) polyamic acid polymers and polyimide polymers having different terminal groups and different structures; (4) polyamino acid polymers, tetracarboxylic dianhydride compounds, and diamine compounds, Among them, at least one of the tetracarboxylic dianhydride compound and the diamine compound is different from the structure of the tetracarboxylic dianhydride component (a) and the diamine component (b) used to form the polyamino acid polymer. (5) a polyfluorene imine polymer, a tetracarboxylic dianhydride compound, and a diamine compound, wherein at least one of the tetracarboxylic dianhydride compound and the diamine compound is used to form a polyfluorene imine polymer; The tetracarboxylic dianhydride component (a) and the diamine component (b) have different structures; (6) polyfluorinated acid polymer, polyfluorinated imine polymer, tetracarboxylic dianhydride compound, and diamine A compound in which at least one of a tetracarboxylic dianhydride compound and a diamine and a tetracarboxylic dianhydride component (b) used to form a polyfluorinated polymer or a polyfluorinated imine polymer, and The amine components (b) have different structures; (7) two polyamine polymers, tetracarboxylic dianhydride compounds, and diamine compounds with different structures; (8) two polyamines with different structures Amine polymer, tetracarboxylic dianhydride compound and diamine compound; (9) two polyamino acid polymers and diamine compounds whose terminal groups are acid anhydride groups and different in structure; (10) two terminal groups are amines Polyamine polymers and tetracarboxylic dianhydride compounds with different base groups and structures; (11) two polyamidoimide polymers and diamine compounds with different terminal groups that are acid anhydride groups and different structures; (12) two This kind of polyfluorene imine polymer having a terminal group as an amine group and having a different structure and a tetracarboxylic dianhydride compound.

Within the range that does not affect the efficacy of the present invention, preferably, the polyfluorene acid polymer, the polyfluorene imine polymer, and the polyfluorine-based block copolymer may be the ends after the molecular weight is adjusted first. Modified polymers. By using a terminal-modified polymer, the coating performance of the liquid crystal alignment agent can be improved. The method for preparing the terminal-modified polymer can be obtained by adding a monofunctional compound while the polyamic acid polymer undergoes a polycondensation reaction. The monofunctional compound includes, but is not limited to (1) a monobasic acid anhydride, For example: maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride or n-hexadecylsuccinic anhydride; (2) Monoamine compounds, for example: aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecaneamine, n-deca Monoamine compounds such as dialkylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecanylamine, n-octadecylamine, or n-eicosylamine (3) a monoisocyanate compound, such as a monoisocyanate compound such as phenyl isocyanate or naphthyl isocyanate.

The polymer (A) of the present invention has a polystyrene-equivalent weight average molecular weight measured by a gel permeation chromatography method of 10,000 to 90,000, preferably 12,000 to 75,000, and more preferably 15,000 to 60,000.

The solvent (B) used in the liquid crystal alignment agent of the present invention is not particularly limited, as long as it is a soluble polymer (A) and any other component and does not react therewith, it is preferably the same as the aforementioned synthetic polyfluorene The solvent used in the amino acid may be used in combination with the lean solvent used in the synthesis of the polyamino acid.

Specific examples of the solvent (B) include, but are not limited to, N-methyl-2-pyrrolidone (NMP), γ-butyrolactone, γ-butyrolactam, 4-hydroxy-4- Methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol Ethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetic acid Ester, 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 or N, N-dimethylformamide or N, N-dimethyl acetamide and the like. The solvent (B) may be used alone or in combination.

Based on the use amount of the polymer (A) being 100 parts by weight, the use amount of the solvent (B) is 800 to 4000 parts by weight, preferably 900 to 3500 parts by weight, and more preferably 1000 to 3000 parts by weight.

The additive (C) of the liquid crystal alignment agent of the present invention contains a carboxylic acid compound (c-1), and the carboxylic acid compound (c-1) has a structure represented by the following formula (III): Formula (III) In formula (III), R ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms; R ² to R ⁶ are each independently a hydrogen atom, a hydroxyl group, -X-COOH, and a carbon number of 1 Alkyl to 6, alkenyl with 2 to 6 carbons, alkynyl with 2 to 6 carbons, cycloalkyl with 3 to 7 carbons, aryl with 6 to 12 carbons, COOR ⁷ , OR OR ⁸ or two adjacent R ² to R ⁶ groups together form a ring; X is a single bond or an alkylene group having 1 to 6 carbons; and R ⁷ and R ⁸ are each 1 to 20 carbons Alkyl.

In a preferred example, at least one of R ² to R ⁶ of the carboxylic acid compound (c-1) is a hydroxyl group, so that the obtained liquid crystal display device can have a better accumulation after photo-alignment. Charge elimination.

In another preferred example, based on at least one of R ² to R ⁶ of the carboxylic acid compound (c-1) is a hydroxyl group, at least one of the above-mentioned hydroxyl groups is ortho or para to the carboxylic acid group, In this way, the prepared liquid crystal display element can have better accumulated charge erasability after photo-alignment.

In another preferred example, R ¹ of the carboxylic acid compound (c-1) is a single bond, so that the obtained liquid crystal display device can have better accumulated charge elimination after photo-alignment.

Specifically, the carboxylic acid compound (c-1) may include, but is not limited to, the compounds shown below.

In a preferred example, the carboxylic acid compound (c-1) may include 2-hexyl-6-hydroxybenzoic acid, salicylic acid, 4-hydroxybenzoic acid, 6-methylsalicylic acid, 3-methyl Salicylic acid, o-thymolic acid, 2,3-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 1,4-dihydroxybenzoic acid, 3-methoxysalicylic acid, 4-methoxywater Salicylic acid, vanillic acid, gallic acid, 2,3,4-trihydroxybenzoic acid, 2,3,6-trihydroxybenzoic acid, 2,4,5-trihydroxybenzoic acid, 3-O-methylgalactate Acid or syringic acid.

The carboxylic acid compounds (c-1) listed above can be used alone or in combination.

Based on 100 parts by weight of the polymer (A), the use amount of the carboxylic acid compound (c-1) is 3 to 30 parts by weight, preferably 4 to 25 parts by weight, and 5 parts by weight It is more preferably 20 parts by weight. If the carboxylic acid compound (c-1) is not contained in the liquid crystal alignment agent, the formed liquid crystal display element has poor stored charge erasability after photo alignment.

The additive (C) may further include an epoxy compound or a silane compound having a functional group, etc., within a range not affecting the efficacy of the present invention.

The aforementioned epoxy compound may include but is not limited to 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, glycerin diglycidyl ether, 2,2-dibromoneopentyl Glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-di Toluenediamine, 1,3-bis (N, N-diepoxypropylaminomethyl) cyclohexane, N, N, N ', N'-tetraepoxypropyl-4,4'-di Aminodiphenylmethane, N, N-glycidyl-p-glycidoxyaniline, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N-diepoxypropyl) aminopropyltrimethoxysilane and the like.

Based on the use amount of the polymer (A) being 100 parts by weight, the use amount of the epoxy compound is generally 40 parts by weight or less, preferably 0.1 to 30 parts by weight.

The functional silane compound may include, but is not limited to, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2- Aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyl Dimethoxysilane, 3-ureidopropyltrimethoxy silane, 3-ureidopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethylsilane Oxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylene Ethyltriamine, 10-trimethoxysilyl-1,4,7-triazine, 10-triethoxysilyl-1,4,7-triazine, 9-trimethoxysilyl -3,6-Diazinyl acetate, 9-triethoxysilyl-3,6-diazinyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N -Benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane N- bis (oxyethylene) -3-aminopropyl trimethoxy Silane, N- bis (oxyethylene) -3-aminopropyl triethoxy silane-like.

Based on the use amount of the polymer (A) being 100 parts by weight, the use amount of the silane compound is generally 10 parts by weight or less, preferably 0.5 to 10 parts by weight.

The manufacturing method of the liquid crystal alignment agent of the present invention is not particularly limited, and a general mixing method may be adopted. For example, the tetracarboxylic dianhydride component (a) and the diamine component (b) are first mixed uniformly to form a reaction. Polymer (A). Next, the solvent (B) is added to the polymer (A) at a temperature of 0 ° C to 200 ° C, and the additive (C) is added, and the stirring may be continued until the polymer is dissolved. Preferably, the polymer (A) is added to the solvent (B) and the additive (C) is added at a temperature of 20 ° C to 60 ° C.

The present invention further provides a liquid crystal alignment film, which is formed by the aforementioned liquid crystal alignment agent.

The invention further provides a method for manufacturing a liquid crystal alignment film, comprising forming the liquid crystal alignment film by using the liquid crystal alignment agent prepared by the method for manufacturing a liquid crystal alignment agent.

The liquid crystal alignment film of the present invention can be prepared by coating the liquid crystal alignment agent as described above on a substrate and drying and baking.

The substrate for coating the liquid crystal alignment agent of the present invention is selected from transparent materials. The transparent materials include, but are not limited to, alkali-free glass, soda-lime glass, hard glass (Pales glass), and quartz for liquid crystal display devices. Glass, polyethylene terephthalate, polybutylene terephthalate, polyether fluorene, polycarbonate, etc. In order to simplify the manufacturing process, a substrate having an ITO electrode or the like for liquid crystal driving is preferably used. In addition, in a reflective liquid crystal display element, an opaque material such as a silicon wafer may be used as a substrate on one side, and a reflective material such as aluminum may be used as an electrode at this time. Examples of the method for applying the liquid crystal alignment agent of the present invention include a spin coating method, a printing method, and an inkjet method.

When the liquid crystal alignment agent of the present invention is applied, the temperature and time for drying and baking can be arbitrarily selected. Generally, in order to fully remove the organic solvent contained, it can be dried at 50 to 120 ° C for 1 to 10 minutes, and then baked at 150 to 300 ° C for 5 to 120 minutes. The thickness of the coating film after baking is not particularly limited, but the reliability of an excessively thin liquid crystal display element may be low, so the thickness may be 5 to 300 nm, preferably 10 to 200 nm.

The liquid crystal alignment agent of the present invention can also be used in a conventional rubbing alignment process, but is particularly suitable for a photo alignment process.

Specific examples of the photo-alignment treatment include, for example, a method in which the surface of the coating film is irradiated with directionally polarized radiation, and optionally subjected to a heat treatment at a temperature of 150 to 250 ° C. to give the liquid crystal alignment energy. The wavelength of radiation can be ultraviolet and visible light with a wavelength of 100 to 800 nm. Among them, ultraviolet rays having a wavelength of 100 to 400 nm are preferable, and a wavelength of 200 to 400 nm is more preferable. In addition, in order to improve the alignment of the liquid crystal, the coating film substrate may be heated at 50 to 250 ° C while radiating radiation. The radiation dose is preferably in the range of ¹ to 10,000 mJ / cm ² , and more preferably in the range of 100 to 5,000 mJ / cm ² .

The liquid crystal alignment film prepared as described above can stably align liquid crystal molecules in a certain direction.

The present invention also provides a liquid crystal display device including the aforementioned liquid crystal alignment film.

The present invention also provides a method for manufacturing a liquid crystal display element, including forming a liquid crystal display element using the liquid crystal alignment film obtained by the method for manufacturing a liquid crystal alignment film.

Referring to FIG. 1, in an embodiment, the liquid crystal display element 100 of the present invention includes a first unit 110, a second unit 120, and a liquid crystal unit 130. The second unit 120 is spaced apart from the first unit 110, and the liquid crystal unit 130 is disposed. Between the first unit 110 and the second unit 120.

The first unit 110 includes a first substrate 112, an electrode 114, and a first liquid crystal alignment film 116. The electrode 114 is formed on the surface of the first substrate 112 in a dentate pattern, and the first liquid crystal alignment film 116 is formed on the electrode. 114 surface.

The second unit 120 includes a second substrate 122 and a second liquid crystal alignment film 126. The second liquid crystal alignment film 126 is formed on a surface of the second substrate 122.

The first substrate 112 and the second substrate 122 are selected from transparent materials. The transparent materials include, but are not limited to, alkali-free glass, soda-lime glass, hard glass (Pales glass), and quartz glass used in liquid crystal display devices. , Polyethylene terephthalate, polybutylene terephthalate, polyether fluorene, polycarbonate, etc. The material of the electrode 114 is a transparent electrode selected from tin oxide (SnO2), indium oxide-tin oxide (In2O3-SnO2), or a metal electrode such as chromium.

The first liquid crystal alignment film 116 and the second liquid crystal alignment film 126 are the above-mentioned liquid crystal alignment films, respectively, and their function is to make the liquid crystal cell 130 form a pretilt angle, and the liquid crystal cell 130 can be driven by the parallel electric field generated by the electrode 114.

The liquid crystal used in the liquid crystal cell 130 may be used alone or in combination of a plurality of types. The liquid crystal includes, but is not limited to, a diaminobenzene liquid crystal, a pyridazine liquid crystal, a shiff base liquid crystal, and an azo oxide group. (azoxy) type liquid crystal, biphenyl type liquid crystal, phenylcyclohexane type liquid crystal, biphenyl type liquid crystal, phenylcyclohexane type liquid crystal, ester type liquid crystal, terphenyl , Biphenylcyclohexane type liquid crystal, pyrimidine type liquid crystal, dioxane type liquid crystal, bicyclooctane type liquid crystal, cubane type liquid crystal, etc. Cholesteryl liquid crystals such as cholesterol ester (cholesteryl chloride), cholesterol nonanoate (cholesteryl nonanoate), and cholesterol carbonate (cholesteryl carbonate) are also added, or the trade names are "C-15", "CB-15" Chiral agents (manufactured by Merck), etc., or ferroelectric liquid crystals, such as p-decoxybenzylidene-p-amino-2-methylbutyl cinnamate.

The liquid crystal display element produced by the liquid crystal alignment agent of the present invention is suitable for various types of nematic liquid crystals, such as TN, STN, TFT, VA, IPS and other liquid crystal display elements. In addition, depending on the selected liquid crystal, it can also be used for liquid crystal display elements having different strong electromotive force or anti-strong electromotive force. Among the above-mentioned liquid crystal display elements, it is particularly suitable for an IPS-type liquid crystal display element.

The following examples are used to explain the present invention in detail, but it is not meant to limit the present invention to the contents disclosed in these examples. Synthesis of diamine compound (b-1) Synthesis example b-1-1

0.30 mole (44.45 g) of 1,3-dioxane-5,5-dimethanol, 0.66 mole (31.68 g of suspension) of sodium hydride (NaH; 50% by weight oily suspension), 540 Mix toluene and 360 ml of N, N-dimethylformamide, and stir at 80 ° C for 1 hour. Next, after cooling the above reaction mixture to 20 ° C, 0.63 mole (88.89 g) of 4-fluoronitrobenzene dissolved in 180 ml of N, N-dimethylformamide was added dropwise over 1 hour. The above reaction mixture. After completion of the dropwise addition, the mixture was stirred and reacted at 110 ° C for 64 hours. After the reaction mixture was cooled, distilled water was added and extraction was performed with dichloromethane. The dichloromethane layer was washed with distilled water, dried over magnesium sulfate, and then the solvent was removed under reduced pressure. The obtained solid was recrystallized with ethanol to obtain Compound 1. Under a nitrogen atmosphere, 0.19 mol of compound 1, 3.35 g of a palladium-carbon catalyst (Pd / C), 300 ml of tetrahydrofuran, and 300 ml of ethanol were mixed and stirred at 60 ° C. Next, 47.6 ml of hydrazine hydrate was added dropwise over 1 hour, and then stirred and reacted at 60 ° C for 4 hours. After completion of the reaction, the palladium-carbon catalyst was removed from the reaction mixture by suction filtration. The obtained solid is recrystallized from ethanol to obtain a compound represented by the formula (I'-1). Synthesis Example b-1-2

Synthesis Example b-1-2 was prepared separately by the same procedure as Synthesis Example b-1-1, and the difference was that 0.30 mole of 1,3-dioxane-5,5-dimethanol was replaced. Is 0.30 mole of 2-butyl-1,3-dioxane-5,5-dimethanol (molecular weight: 204.26), and 4-fluoronitrobenzene is replaced with 3-fluoronitrobenzene to obtain, for example, A compound represented by the formula (I'-4). Synthesis Example b-1-3

Synthesis Example b-1-3 was prepared separately by the same procedure as Synthesis Example b-1-1, and the difference was that 0.30 mole of 1,3-dioxane-5,5-dimethanol was replaced. 1,3-dioxane-5-methanol-5-n-propanol (molecular weight: 176.21) of 0.30 mole to obtain a compound represented by the formula (I'-8). Synthesis Example b-1-4

Synthesis Example b-1-4 was prepared separately by the same procedure as Synthesis Example b-1-1, and the difference was that 0.30 mole of 1,3-dioxane-5,5-dimethanol was replaced. It was 0.30 mole of 2- (chloromethyl) -1,3-dioxane-5,5-dimethanol (molecular weight: 196.63) to obtain a compound represented by the formula (I'-10). Synthesis Example b-1-5

Synthesis Example b-1-5 was prepared separately by the same procedure as Synthesis Example b-1-1, and the difference was that 0.30 mole of 1,3-dioxane-5,5-dimethanol was replaced. 0.30 mole of 2-([1,1'-di (cyclohexyl)]-4-yl) -1,3-dioxane-5,5-dimethanol (molecular weight: 312.44) to obtain the formula (I'-14). Synthesis Example b-1-6

Synthesis Example b-1-5 was prepared separately by the same procedure as Synthesis Example b-1-1, and the difference was that 0.30 mole of 1,3-dioxane-5,5-dimethanol was replaced. 0.30 mole of 2-phenyl-1,3-dioxane-5,5-diol (molecular weight: 196.20) to obtain a compound represented by the formula (I'-15). Synthesis Example b-1-7

Mix 0.5 mol (103.12 g) of 2-propoxy-1,3-dioxane-5,5-dimethanol, 1.50 mol (207.9 ml) of triethylamine, and 1200 ml of tetrahydrofuran. Stir under the bath. After 1.05 mol (194.84 g) of 4-nitrobenzidine chloride dissolved in 600 ml of tetrahydrofuran was added dropwise to the aforementioned solution over 2 hours, it was stirred and reacted at 25 ° C for 4 hours. Next, ethyl acetate was added to the reaction mixture, and after washing with distilled water, the solvent was removed under reduced pressure. The obtained solid was recrystallized with ethanol to obtain compound 2. Under a nitrogen atmosphere, 0.39 moles of compound 2, 6.87 g of a palladium-carbon catalyst (Pd / C), 600 ml of tetrahydrofuran, and 600 ml of ethanol were mixed and stirred at 60 ° C. After 97.6 ml of hydrazine hydrate was dropped into the aforementioned solution over 1 hour, it was stirred and reacted at 60 ° C for 4 hours. After completion of the reaction, the palladium-carbon catalyst was removed from the reaction mixture by suction filtration, and the solvent was removed under reduced pressure. The obtained solid is recrystallized from ethanol to obtain a compound represented by the formula (I'-21). Synthesis Example b-1-8

Mix 0.5 mol (95.08 g) of 2-methyl-1,3-dioxane-5,5-dicarboxylic acid, 400 ml of methylene chloride and a small amount of dimethylformamide, and mix at 80 It was stirred and reacted at 1 ° C for 1 hour. The water-flow suction was used for vacuum suction filtration to remove unreacted thionium chloride from the reaction mixture. After that, 680 ml of dichloromethane was added to form a solution. After passing 150 ml of distilled water into the above solution in three portions, water was removed with magnesium sulfate and the solvent was removed under a reduced pressure environment to obtain a solid. The above solid was dissolved with 450 ml of tetrahydrofuran to form a solution (1). 1.05 mole (146.07 g) of 3-nitrophenol, 800 ml of tetrahydrofuran, 1.50 mole (207.9 ml) of triethylamine were mixed and stirred in an ice bath. Next, the solution (1) was dropped into a mixed solution of 3-nitrophenol, tetrahydrofuran, and triethylamine over 1 hour, and then stirred and reacted at 25 ° C for 4 hours. Next, ethyl acetate was added to the reaction mixture, and after washing with distilled water, the solvent was removed under reduced pressure to obtain a solid. Recrystallization of the obtained solid with ethanol gave 0.41 mole of Compound 3. Under a nitrogen atmosphere, 0.41 mol of Compound 3, 8.20 mol (536.20 g) of zinc, 1.64 mol (87.72 g) of ammonium chloride, 1500 ml of ethanol, and 1500 ml of tetrahydrofuran were mixed at 0 ° C. Stir. Thereafter, 200 ml of distilled water was added, and the mixture was stirred and reacted at 25 ° C for 8 hours. The reaction mixture was suction-filtered to remove insoluble catalyst, and the solution obtained by adding ethyl acetate was washed with distilled water. After washing the solution, the solvent is removed under a reduced pressure environment to obtain a solid. The obtained solid was recrystallized with ethanol to obtain a compound represented by the formula (I'-26). Synthetic polymer (A) Synthesis example A-1-1

A 500-ml four-necked conical flask was provided with a nitrogen inlet, a stirrer, a condenser tube, and a thermometer, and nitrogen was introduced. Then, 0.33 g (0.001 mole) of the diamine compound (b-1-1) represented by the formula (I'-1) and 5.30 g (0.049 mole) of p-diaminebenzene (b-2) were added. -1) and 80 g of N-methyl-2-pyrrolidone (hereinafter referred to as NMP), and stirred at room temperature until dissolved. Next, 1.96 g (0.01 mole) of the compound (a-1-1) represented by the formula (II-1) and 8.72 g (0.04 mole) of pyromellitic dianhydride (a-2- 1) and 20 g of NMP, and reacted at room temperature for 2 hours. After the reaction, the reaction solution was poured into 1500 ml of water to precipitate a polymer, the obtained polymer was filtered, and the steps of washing and filtering with methanol were repeated three times. After that, the product was placed in a vacuum oven and dried at a temperature of 60 ° C., thereby obtaining a polymer (A-1-1), and its formula is shown in Table 1. Synthesis Example A-1-2 to A-1-10 and Synthesis Comparative Example A'-1-1

Synthesis Examples A-1-2 to A-1-10 and Synthesis Comparative Example A'-1-1 used the same production method as the method for producing the polymer (A-1-1) of Synthesis Example A-1-1, The difference lies in Synthesis Examples A-1-2 to A-1-10 and Synthesis Comparative Example A'-1-1. The type and amount of raw materials in the polymer were changed. The formula is shown in Table 1. To repeat. Synthesis Example A-1-11

Polymer A-1-11 was prepared by the same steps as in Synthesis Example A-1-1, in which the types of ingredients and the amounts used were the same, except that the tetracarboxylic dianhydride component and diamine group were mixed After serving, 0.49 g of 3-methoxysalicylic acid (referred to as C-1-1 in Table 2-1) was added. Synthesis Example A-2-1

A 500-ml four-necked conical flask was provided with a nitrogen inlet, a stirrer, a heater, a condenser tube, and a thermometer, and nitrogen was introduced. Then, 0.33 g (0.001 mole) of b-1-1, 9.71 g (0.049 mole) of 4,4'-diaminodiphenylmethane (b-2-2), and 80 g of NMP were added, And stirred at room temperature until dissolved. Next, 1.96 grams (0.01 mole) of a-1-1, 8.72 grams (0.04 mole) of a-2-1, and 20 grams of NMP were added. After 6 hours of reaction at room temperature. After the reaction was completed, 97 g of NMP, 2.55 g of acetic anhydride, and 19.75 g of pyridine were added to the aforementioned reaction solution, the temperature was raised to 60 ° C., and stirring was continued for 2 hours to perform the amidine imidization reaction. After the reaction, the reaction solution was poured into 1500 ml of water to precipitate a polymer, the obtained polymer was filtered, and the steps of washing and filtering with methanol were repeated three times. After that, the product was placed in a vacuum oven and dried at a temperature of 60 ° C., thereby obtaining a polymer (A-2-1), and its formula is shown in Table 1. Synthesis Examples A-2-2 to A-2-4 and Synthesis Comparative Example A'-2-1

Synthesis Examples A-2-2 to A-2-4 and Synthesis Comparative Example A'-2-1 used the same preparation method as the polymer (A-2-1) composition of Synthesis Example A-2-1, but different The point is that Synthesis Examples A-2-2 to A-2-7 and Synthesis Comparative Example A'-2-1 change the type and amount of raw materials in the polymer and the reaction temperature and reaction time of the dehydration ring-closing reaction. The formula is as follows It is shown in Table 1 and is not repeated here. Table 1: in FIG. 1: Example 1 Preparation of Liquid Crystal Alignment Agent

100 parts by weight of the polymer (A-1-1) of Synthesis Example A-1-1, 1050 parts by weight of NMP, and 3 parts by weight of 3-methoxysalicylic acid were weighed and stirred at room temperature. Thus, the liquid crystal alignment agent of Example 1 can be obtained. Preparation of liquid crystal alignment film and liquid crystal display element

The prepared liquid crystal alignment agent is spin-coated on a glass substrate, wherein a pixel electrode is formed on the glass substrate, wherein the pixel electrode has a pair of ITO electrodes (electrode width: 10 μm, electrode interval: 10 μm (Electrode height: 50nm) for the IPS driving electrode, the pair of ITO electrodes each have a dentate shape, and the dentate portions of each pair are arranged to be separated and bite. After that, the glass substrate coated with the liquid crystal alignment agent was dried on a hot plate at 80 ° C. for 5 minutes, and then baked in a hot air circulation oven at 250 ° C. for 60 minutes to form a coating film having a film thickness of 100 nm.

A polarizing plate was irradiated with ultraviolet light having a wavelength of 254 nm to the coating film surface to prepare a substrate having a liquid crystal alignment film. Next, similarly, a coating film is formed on the opposite substrate and subjected to an alignment treatment, the opposite substrate being a glass substrate having no electrodes but having a columnar spacer having a height of 4 μm.

The above two substrates are a set, and a sealant is printed on one of them, and the other is bonded to the liquid crystal alignment film in an orientation direction of 0 °, and then the sealant is hardened to obtain an empty one. Unit cell. This empty cell was injected into a liquid crystal MLC-2041 (manufactured by Merck) under a reduced pressure injection method, and the injection port was sealed to obtain a liquid crystal display element of Example 1.

The liquid crystal display element of Example 1 was evaluated by an evaluation method described later, and the results are shown in Table 2-1. Examples 2 to 20 and Comparative Examples 1 to 6

Examples 2 to 20 and Comparative Examples 1 to 6 use the same preparation method as the liquid crystal alignment agent of Example 1, except that Examples 2 to 20 and Comparative Examples 1 to 6 change the type and use of raw materials in the liquid crystal alignment agent. The amounts, their formulations and evaluation results are shown in Table 2-1, Table 2-2 and Table 3, respectively, and are not repeated here. table 2-1: Table 2-2: table 3: The light distribution of the accumulated charge eliminating rearwardly

The liquid crystal display elements prepared by using Examples 1 to 20 and Comparative Examples 1 to 6 and irradiated with ultraviolet rays having a wavelength of 254 nm were each applied with a DC voltage of 3 volts for 30 minutes, and then an electric measuring machine (TOYO Corporation Ltd., model model 6254) measured the liquid crystal display after the element voltage release accumulated voltage (V _R1) and the voltage is released 15 minutes accumulated voltage (V _R2), by the formula (1) to calculate the accumulated charge elimination slope (V _S ) And evaluated based on the following criteria. Among them, the lower the accumulated charge elimination slope after irradiating ultraviolet rays with a wavelength of 254 nm, the better the elimination of the accumulated charge after the optical alignment of the liquid crystal display element: Formula (1) ※: 75% <V _S. ：: 70% <V _S ≦ 75%. ○: 65% <V _S ≦ 70%. △: 60% <V _S ≦ 65%. ×: V _S ≦ 60%.

The above embodiments are only for explaining the principle of the present invention and its effects, but not for limiting the present invention. Modifications and changes made by those skilled in the art to the above embodiments still do not violate the spirit of the present invention. The scope of rights of the present invention should be listed in the scope of patent application described later.

100‧‧‧LCD display element

110‧‧‧ Unit 1

112‧‧‧First substrate

114‧‧‧ electrode

116‧‧‧The first liquid crystal alignment film

120‧‧‧ Unit 2

122‧‧‧Second substrate

126‧‧‧Second LCD alignment film

130‧‧‧LCD unit

FIG. 1 is a schematic structural diagram of a liquid crystal display device according to an embodiment of the present invention.

Claims (17)

A liquid crystal alignment agent, comprising: a polymer (A) selected from the group consisting of a polyamic acid resin and a polyimide resin; a solvent (B); and an additive (C); wherein the polymer (A) contains The structure shown in the following formula (I): In formula (I), in formula (I), Z _{1 is} each and independently an ether bond or an ester bond; R _{1 is} each and independently a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; each of R _{2 is} And is independently a halogen atom, an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbon atoms, and a carbon number is An alkoxy group of 1 to 9, a cycloalkyl group having 3 to 12 carbons, or an aryl group having 6 to 12 carbons; m is an integer from 0 to 4; and * ^a represents a bonding point; additive (C) Containing a carboxylic acid compound (c-1) represented by the following formula (III): Formula (III) In formula (III), R ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms; R ² to R ⁶ are each independently a hydrogen atom, a hydroxyl group, -X-COOH, and a carbon number of 1 Alkyl to 6, alkenyl with 2 to 6 carbons, alkynyl with 2 to 6 carbons, cycloalkyl with 3 to 7 carbons, aryl with 6 to 12 carbons, COOR ⁷ , OR OR ⁸ or two adjacent R ² to R ⁶ groups together form a ring; X is a single bond or an alkylene group having 1 to 6 carbons; and R ⁷ and R ⁸ are each 1 to 20 carbons Alkyl. For example, the liquid crystal alignment agent of claim 1, wherein Z ₁ of the structure represented by formula (I) is an ether bond. The liquid crystal alignment agent according to claim 1, wherein at least one of R ² to R ⁶ of the carboxylic acid compound (c-1) is a hydroxyl group. The liquid crystal alignment agent according to claim 3, wherein at least one of R ² , R ⁴ and R ⁶ of the carboxylic acid compound (c-1) is a hydroxyl group. The liquid crystal alignment agent according to claim 1, wherein the used amount based on the polymer (A) is 100 parts by weight, and the used amount of the carboxylic acid compound (c-1) is 3 to 30 parts by weight. For example, the liquid crystal alignment agent of claim 1, wherein the used amount based on the polymer (A) is 100 parts by weight, the used amount of the solvent (B) is 800 to 4000 parts by weight; and the used amount of the additive (C) is 3 Part by weight to 50 parts by weight. A liquid crystal alignment film is formed of the liquid crystal alignment agent according to any one of claims 1 to 6. A liquid crystal display element comprising the liquid crystal alignment film of claim 7. A method for manufacturing a liquid crystal alignment agent, comprising: reacting a tetracarboxylic dianhydride component (a) and a diamine component (b) to obtain a polymer (A), wherein the diamine component (b) includes the following Diamine compound (b-1) represented by formula (I '): Formula (I ') In Formula (I'), Z _{1 is} each and independently an ether bond or an ester bond; R _{1 is} each and independently a single bond, a methylene group, or an alkylene group having 2 to 6 carbon atoms; R ₂ are each independently a halogen atom, an alkyl group having 1 to 4 carbons or an alkoxy group having 1 to 4 carbons; R ₃ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 9 carbons, carbon An alkoxy group having a number of 1 to 9, a cycloalkyl group having a carbon number of 3 to 12, or an aryl group having a carbon number of 6 to 12; and m is an integer of 0 to 4; providing a solvent (B); providing an additive ( C) comprising a carboxylic acid compound (c-1) represented by the following formula (III): Formula (III) In formula (III), R ¹ is a single bond or an alkylene group having 1 to 6 carbon atoms; R ² to R ⁶ are each independently a hydrogen atom, a hydroxyl group, -X-COOH, and a carbon number of 1 Alkyl to 6, alkenyl with 2 to 6 carbons, alkynyl with 2 to 6 carbons, cycloalkyl with 3 to 7 carbons, aryl with 6 to 12 carbons, COOR ⁷ , OR ⁸ or two adjacent R ² to R ⁶ groups together form a ring; X is a single bond or an alkylene group having 1 to 6 carbons; and R ⁷ and R ⁸ are each 1 to 20 carbons Alkyl; and mixed polymer (A), solvent (B) and additive (C). The method for producing a liquid crystal alignment agent according to claim 9, wherein Z ₁ of the carboxylic acid compound (c-1) of the diamine compound (b-1) represented by the formula (I ') is an ether bond. The method for producing a liquid crystal alignment agent according to claim 9, wherein at least one group of R ² to R ⁶ of the carboxylic acid compound (c-1) is a hydroxyl group. The method for producing a liquid crystal alignment agent according to claim 11, wherein at least one of R ² , R ⁴ and R ⁶ of the carboxylic acid compound (c-1) is a hydroxyl group. For example, the method for producing a liquid crystal alignment agent according to claim 9, wherein the used amount based on the diamine component (b) is 100 moles, and the used amount of the diamine compound (b-1) represented by the formula (I ') is 2 Moore to 20 Moore. The method for manufacturing a liquid crystal alignment agent according to claim 9, wherein the used amount based on the polymer (A) is 100 parts by weight, and the used amount of the carboxylic acid compound (c-1) is 3 to 30 parts by weight. The method for manufacturing a liquid crystal alignment agent according to claim 9, wherein the amount of use based on the polymer (A) is 100 parts by weight, the amount of use of the solvent (B) is 500 to 4,000 parts by weight; and the use of the additive (C) The amount is 3 to 50 parts by weight. A method for manufacturing a liquid crystal alignment film, comprising forming the liquid crystal alignment film by a liquid crystal alignment agent prepared by the method for producing a liquid crystal alignment agent according to any one of claims 9 to 15. A method for manufacturing a liquid crystal display element includes a liquid crystal alignment film formed by the method for manufacturing a liquid crystal alignment film according to claim 16 to form a liquid crystal display element.