TW201930468A - 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 polysiloxane (B) and a solvent (C). The polymer (A) is formed by reacting a first mixture including a tetracarboxylic acid dianhydride component (a1) and a diamine component (a2), and is selected from a polyamide acid polymer, a polyimide polymer, a polyimide-based block copolymer or a combination thereof. The liquid crystal alignment agent of the invention has the advantages of favorable environmental resistance and adhesion strength. Furthermore, the invention also provides a liquid crystal alignment film made by the aforementioned liquid crystal alignment agent, 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 invention relates to a liquid crystal alignment agent and a method for manufacturing the same, a liquid crystal alignment film and a method for manufacturing the same, and a liquid crystal display element, and more particularly to a liquid crystal alignment agent with excellent environmental resistance and adhesion, a method for manufacturing the same, and the liquid crystal alignment Liquid crystal alignment film formed by an agent, a method for manufacturing the same, and a liquid crystal display element having the liquid crystal alignment film.

Generally, in liquid crystal display elements, various driving methods have been developed according to the structure of the electrodes or the physical properties of the liquid crystal molecules used. Currently known driving methods of liquid crystal display elements are, for example, TN type or STN type, VA type, lateral electric field effect display technology type (IPS type), and the like. The liquid crystal display element includes a liquid crystal alignment film for aligning liquid crystal molecules. The material of the liquid crystal alignment film may be, for example, known materials such as polyamic acid, polyimide, polyester, polyorganosiloxane, and the like.

In recent years, in order to control the alignment of liquid crystal molecules of liquid crystal display elements, new technologies such as Polymer Sustained Alignment (PSA) have been proposed, for example, Japanese Publication No. JP 2003-149647. The photopolymerizable component is added to the liquid crystal layer of the liquid crystal cell, and the liquid crystal molecules are tilted under a voltage applied state, and then the liquid crystal cell is irradiated with light, thereby polymerizing the photopolymerizable component, thereby controlling the alignment of the liquid crystal molecules. .

However, when using polymer stabilized alignment technology to control the alignment of liquid crystal molecules, a relatively high light exposure is required, which causes defects such as decomposition of liquid crystal molecules and deterioration of the properties of the liquid crystal alignment film, thereby causing display unevenness of the liquid crystal display element. And panel durability is degraded. On the other hand, if the amount of light irradiation is reduced, the reaction rate of liquid crystal molecules in the formed liquid crystal display element to a voltage change becomes slow. In order to make the liquid crystal alignment agent for forming the coating film achieve the predetermined pretilt angle characteristic with a small amount of light irradiation as much as possible, and the liquid crystal molecules in the formed liquid crystal display element have a fast response speed to voltage, Japanese Patent Publication No. 2011 is currently proposed. -118358 patent technology, which discloses the use of a liquid crystal alignment agent containing a polyorganosiloxane such as (meth) acrylfluorenyl group and a photopolymerizable component of polyimide acid or polyimide on a substrate A liquid crystal alignment film is formed thereon. Next, the substrate is formed into a liquid crystal cell, and when a voltage is applied between the substrates, the liquid crystal cell is irradiated with light to produce a liquid crystal display element.

However, the liquid crystal alignment film and the liquid crystal display element prepared with the liquid crystal alignment agent described above still need to be improved in environmental resistance and adhesion. Therefore, there is an urgent need to propose a liquid crystal alignment agent which can produce a liquid crystal alignment film and a liquid crystal display element having better environmental resistance and adhesion.

The invention provides a liquid crystal alignment agent by providing a special composition. The liquid crystal alignment film and the liquid crystal display element formed by the liquid crystal alignment agent have the advantages of good environmental resistance and adhesion.

Therefore, the present invention relates to a liquid crystal alignment agent comprising: a polymer (A), which is prepared by reacting a first mixture including a tetracarboxylic dianhydride component (a1) and a diamine component (a2); And the polymer (A) is selected from the group consisting of a polyacrylic acid polymer, a polyimide polymer, a polyimide-based block copolymer, or any combination thereof; polysiloxane (B) And solvent (C); wherein the diamine component (a2) includes at least one first diamine compound (a2-1) represented by formula (1): H ₂ N-R _a -NH ₂ formula (1) In formula (1), R _a is _a bivalent unit represented by formula (1-1) to formula (1-11): In formulas (1-1) to (1-11), * is a bonding point; and the polysiloxane (B) includes an epoxy-containing polysiloxane (b1) and a side chain compound (b2) ), And the epoxy-containing polysiloxane (b1) comprises a copolymer obtained by hydrolyzing and partially condensing a second mixture.

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 invention provides a liquid crystal alignment agent, comprising: a polymer (A), which is prepared by reacting a first mixture including a tetracarboxylic dianhydride component (a1) and a diamine component (a2), and the The polymer (A) is selected from the group consisting of a polyamic acid polymer, a polyimide polymer, a polyimide-based block copolymer, or any combination thereof; a polysiloxane (B); and a solvent (C); wherein the diamine component (a1) includes at least one first diamine compound (a2-1) represented by formula (1): H ₂ N-R _a -NH ₂ formula (1) formula (1) ), R _a is _a bivalent unit represented by formula (1-1) to formula (1-11): In formulas (1-1) to (1-11), * is a bonding point; and the polysiloxane (B) includes an epoxy-containing polysiloxane (b1) and a side chain compound (b2) ), And the epoxy-containing polysiloxane (b1) comprises a copolymer obtained by hydrolyzing and partially condensing a second mixture.

The polymer (A) according to the present invention is obtained by reacting a first mixture including a tetracarboxylic dianhydride component (a1) and a diamine component (a2).

Specifically, the polymer (A) is selected from the group consisting of a polyamidopolymer, a polyamidopolymer, a polyamidoblock copolymer, and any combination of the aforementioned polymers. Preferably, the polymer (A) is a combination of a polyamidic acid polymer (A1) and a polyamidoimine polymer (A2).

In a specific example of the present invention, based on the used amount of the polymer (A) being 100 parts by weight, the used amount of the polyamino acid polymer (A1) is 20 to 60 parts by weight, preferably 25 parts by weight. Parts to 60 parts by weight, more preferably 25 parts by weight to 55 parts by weight; and the amount of the polyfluorene imine polymer (A2) used is 40 parts by weight to 80 parts by weight, preferably 40 parts by weight to 75 parts by weight , More preferably from 45 parts by weight to 75 parts by weight. If the amount of the polyfluorinated polymer (A1) and the polyfluorinated imine polymer (A2) falls within the above range, the obtained liquid crystal alignment agent has the best environmental resistance and adhesion. .

The tetracarboxylic dianhydride compound (a1) includes an aliphatic tetracarboxylic dianhydride compound, an alicyclic tetracarboxylic dianhydride compound, an aromatic tetracarboxylic dianhydride compound, and from formula (I-1) to formula (I) -6) At least one of the tetracarboxylic dianhydride compounds represented by the above, or a combination thereof.

Specific examples of the aliphatic tetracarboxylic dianhydride compound, the alicyclic tetracarboxylic dianhydride compound, and the aromatic tetracarboxylic dianhydride compound are listed below, but the present invention is not limited to these specific examples.

Specific examples of the aliphatic tetracarboxylic dianhydride compound may include, but are not limited to, ethane tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, or a combination thereof.

Specific examples of the alicyclic tetracarboxylic dianhydride compound may include, but are not limited to, 1,2,3,4-cyclobutanetetracarboxylic 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-cyclo Butane tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic acid Acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic dianhydride, cis-3,7-dibutyl Cyclopeptyl-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, or a combination of the foregoing compounds.

Specific examples of the aromatic tetracarboxylic dianhydride compound may include, but are not limited to, 3,4-dicarboxyl-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylpyrenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic acid Acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-diphenylethanetetracarboxylic dianhydride, 3,3', 4,4'- Dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3 ', 4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride, 4, 4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylarsine dianhydride, 4,4'- Bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride (4,4'-bis (3,4-dicarboxy phenoxy) diphenylpropane dianhydride), 3,3 ', 4,4'-perfluoroisoprene Propyldiphthalic dianhydride, 3,3 ', 4,4'-diphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (tris) Phenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4'-diphenyl ether dianhydride, bis (Triphenylphthalic acid) -4,4'- Phenylmethane dianhydride, ethylene glycol-bis (anhydrotrimellitate), propylene glycol-bis (anhydromellitate), 1,4-butanediol-bis (anhydromellitate), 1,6-hexanediol-bis (anhydrotrimellitate), 1,8-octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane- Bis (anhydrotrimellitic acid ester), 2,3,4,5-tetrahydrofurantetracarboxylic 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- (tetrahydro- 2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione)}, 1,3,3a, 4,5,9b-hexahydro-5-methyl-5- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b- Hexahydro-5-ethyl-5- (tetrahydro-2,5-dioxo-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) -naphthalene Benzo [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dione (Oxy-3-furyl) -naphthalene [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-ethyl-5- (tetrahydro-2,5-dioxo Yl-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-dioxo Tetrahydrofuranyl) aromatic tetracarboxylic dianhydride compounds such as 3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride or a combination of the foregoing compounds.

The tetracarboxylic dianhydride compounds represented by formula (I-1) to formula (I-6) are shown below. Formula (I-1) Formula (I-2) Formula (I-3) Formula (I-4) Formula (I-5)

In Formula (I-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 each may independently represent a hydrogen atom or an alkyl group. Specific examples of the tetracarboxylic dianhydride compound represented by the formula (I-5) include at least one of compounds represented by the formula (I-5-1) to the formula (I-5-3). Formula (I-5-1) Formula (I-5-2) Formula (I-5-3) Formula (I-6)

In Formula (I-6), A ⁴ represents a divalent group containing an aromatic ring; A ⁵ and A ⁶ may be the same or different, and each independently represents a hydrogen atom or an alkyl group. The tetracarboxylic dianhydride compound represented by the formula (I-6) is preferably a compound represented by the formula (I-6-1). Formula (I-6-1)

The tetracarboxylic dianhydride compound (a1) can be used alone or in combination.

Specific examples of the tetracarboxylic dianhydride compound (a1) preferably include 1,2,3,4-cyclobutane tetracarboxylic dianhydride (1,2,3,4-cyclobutane tetracarboxylic dianhydride), 1,2, 3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,2,4,5-cyclohexane tetra Carboxylic dianhydride, 3,4-dicarboxyl-1,2,3,4-tetrahydronaphthalene-1-succinic dianhydride, pyromellitic dianhydride, 3,3 ', 4, 4'-benzophenone tetracarboxylic dianhydride, 3,3 ', 4,4'-biphenylhydrazone tetracarboxylic dianhydride, a compound represented by the formula (I-1), or a combination of the foregoing compounds.

Based on the total moles of the diamine component (a2) is 100 moles, and the usage amount of the tetracarboxylic dianhydride component (a1) is preferably from 80 moles to 120 moles, more preferably from 85 moles to 115 mol.

The diamine component (a2) according to the present invention includes at least one first diamine compound (a2-1) represented by formula (1): H ₂ N-R _a -NH _{2 in} formula (1) in formula (1) R _a is _a bivalent unit represented by formula (1-1) to formula (1-11): In formulas (1-1) to (1-11), * is a bond; and

In a specific example of the present invention, based on the total used amount of the diamine component (a2) is 100 moles, the used amount of the first diamine compound (a2-1) represented by the formula (1) is 3 to 60 mol, preferably 5 to 50 mol, more preferably 8 to 40 mol. If the first diamine compound (a2-1) is not used, the obtained liquid crystal alignment agent has poor environmental resistance and poor adhesion.

Preferably, the diamine component (a2) of the present invention may further include a second diamine compound (a2-2) represented by formula (2): In formula (2), in formula (2), R ¹⁵ is selected from , , , , and The group consisting of; and R ¹⁶ is an organic group represented by formula (2-1): Formula (2-1) In formula (2-1): R ¹⁷ is hydrogen, fluorine or methyl; R ¹⁸ , R ¹⁹ and R ²⁰ each independently represent a single bond, , , , , , Or C ₁ to C ₃ alkylene; R ²¹ is selected from and A group consisting of: wherein: R ²³ and R ²⁴ each independently represent hydrogen, fluorine or methyl; R ²² is selected from hydrogen, fluorine, C ₁ to C ₁₂ alkyl, and C ₁ to C ₁₂ fluoroalkyl , A group consisting of C ₁ to C ₁₂ alkoxy, -OCH ₂ F, -OCHF ₂ and -OCF ₃ ; a represents an integer of 1 or 2; g, m and i each independently represent an integer of 0 to 4 ; Y, h, and x each independently represent an integer from 0 to 3, and y + h + x ≧ 3; and z1 and z2 each independently represent 1 or 2; when R ¹⁷ , R ¹⁸ , R ¹⁹ , R ²⁰ , When there is a plurality of R ²¹ , R ²³ or R ²⁴ , they are each the same or different.

Specific examples of the second diamine compound (a2-2) include at least one of the diamine compounds represented by the formula (2-2) to the formula (2-9), or a combination thereof. Formula (2-2) Formula (2-3) Formula (2-4) Formula (2-5) Formula (2-6) (2-7) (2-8) Formula (2-9) In Formulas (2-2) to (2-9), B ¹¹ is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

The diamine compound represented by the formula (2-2) to the formula (2-9) is preferably at least one of the diamine compounds represented by the formula (2-10) to the formula (2-15), or combination. Formula (2-10) (2-11) (2-12) (2-13) (2-14) (2-15)

The above-mentioned second diamine compound (a2-2) may be used singly or in combination of two or more kinds.

In a specific example of the present invention, based on the total used amount of the diamine component (a2) is 100 moles, the used amount of the second diamine compound (a2-2) represented by the formula (2) is 5 to 60 mol, preferably 8 to 50 mol, and more preferably 10 to 40 mol.

Preferably, the diamine component (a2) of the present invention may further include a third diamine compound (a2-3) represented by formula (3): Formula (3) In Formula (3), X is an organic group containing a C ₆ to C ₃₀ aromatic ring; and n is an integer of 1 to 4.

The third diamine compound (a2-3) is not limited as long as it has a carboxylic acid group, and the third diamine compound (a2-3) may include, but is not limited to, an aliphatic diamine and an alicyclic ring. Group diamine, aromatic diamine or diamine organosiloxane. The third diamine compound (a2-3) is preferably an alicyclic diamine or an aromatic diamine, and more preferably an aromatic diamine.

The third diamine compound (a2-3) preferably has 1 to 4 carboxylic acid groups, and more preferably has 1 or 2 carboxylic acid groups.

The third diamine compound (a2-3) is selected from the group consisting of formulae (3-1) to (3-5); Equation (3-1) Formula (3-2) Equation (3-3) Formula (3-4) Formula (3-5) In formulas (3-1) to (3-5), X ₁ and X ₃ independently represent a single bond, -CH _2- , -C ₂ H _4- , -C (CH ₃ ) _2- , -CF _2- , -C (CF ₃ ) _2- , -O-, -CO-, -NH-, -N (CH ₃ )-, -CONH-, -NHCO-, -CH ₂ O- _{, -OCH 2 -, - COO -} , - OCO -, - CON (CH 3) - or _{-N (CH 3) CO-; X} 2 represents a C ₁ to C straight chain alkyl group or the C ₅ to C _{5 1} N1 and n7 independently represent integers from 1 to 4; n2 and n3 independently represent integers from 0 to 4; and n2 + n3 is an integer from 1 to 4; and n4, n5, and n6 independently represent 1 to 4 An integer of 5.

Preferably, in formula (3-1), n1 may represent 1 or 2; in formula (3-2), X ₁ represents a single bond, -CH _2- , -C ₂ H _4- , -C ( CH ₃ ) _2- , -O-, -CO-, -NH-, -N (CH ₃ )-, -CONH-, -NHCO-, -COO-, or -OCO-, and n2 and n3 represent 1 at the same time; In formula (3-5), X ₃ represents a single bond, -CH _2- , -O-, -CO-, -NH-, -CONH-, -NHCO-, -CH ₂ O-, -OCH _2- , -COO- or -OCO-, and n7 represents 1 or 2.

Specific examples of the third diamine compound (a2-3) are diamine compounds represented by the following formulae (3-6) to (3-16): In formulas (3-14) and (3-15), X ₅ may represent a single bond, -CH _2- , -O-, -CO-, -NH-, -CONH-, -NHCO-, -CH ₂ O-, -OCH _2- , -COO- or -OCO-.

The third diamine compound (a2-3) may be used alone or in combination.

In a specific example of the present invention, based on the total used amount of the diamine component (a2) is 100 moles, the used amount of the third diamine compound (a2-3) represented by the formula (3) is 3 to 97 mol, preferably 5 to 90 mol, and more preferably 10 to 80 mol. When the second diamine compound (a2-2) or the third diamine compound (a2-3) is used, the environmental resistance of the obtained liquid crystal alignment agent is better.

Preferably, the diamine component (a2) of the present invention may further include other diamine compounds (a2-4).

The other diamine compound (a2-4) may include, but is not limited to, 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diamine Pentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diamine Decane, 4,4'-diaminoheptane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-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-aminopropoxy Ethane), 4,4'-diaminodicyclohexylmethane, 4,4'-diamino-3,3'-dimethyldicyclohexylamine, 1,3-diaminocyclohexane , 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienediamine, tricyclic (6.2.1.0, ^2,7 ) -undecenedimethylene Diamine, 4,4'-methylenebis (cyclohexylamine), 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4 ' -Diaminodiphenylphosphonium, 4,4'-diaminobenzidineaniline, 4,4'-diaminodiphenyl ether, 3,4'- Amino diphenyl ether, 1,5-diamino naphthalene, 5-amino-1- (4'-aminophenyl) -1,3,3-trimethylhydroindene, 6-amino- 1- (4'-aminophenyl) -1,3,3-trimethylhydroindene, hexahydro-4,7-methyl bridged indenyldimethylene diamine, 3,3'-di Aminobenzophenone, 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) 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] hexafluoropropane, 4,4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octa Fluorobiphenyl, 5- [4- (4-n-pentylcyclohexyl) cyclohexyl] benzene Methylene-1,3-diaminobenzene {5- [4- (4-n-pentylcyclohexyl) cyclohexyl] phenylmethylene-1,3-diaminobenzene}, 1,1-bis [4- (4-aminophenylbenzene (Oxy) phenyl] -4- (4-ethylphenyl) cyclohexane {1,1-bis [4- (4-aminophenoxy) phenyl] -4- (4-ethylphenyl) cyclohexane} or the following formula ( 4-1) to other diamine compounds represented by formula (4-25).

The diamine compound represented by the formula (4-1) is shown below: Formula (4-1) In formula (4-1), 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 compound (a2-4) represented by the above formula (4-1) is preferably 2,4-diaminophenyl ethyl formate, 3,5-diamine 3,5-diaminophenyl ethyl formate, 2,4-diaminophenyl propyl formate, 3,5-diaminophenyl propyl formate (3,5-diaminophenyl propyl formate), 1-dodecoxy-2,4-diaminobenzene, 1-hexadecyloxy-2,4- 1-hexadecoxy-2,4-diaminobenzene, 1-octadecoxy-2,4-diaminobenzene, or the following formula (4-1 -1) to other diamine compounds represented by formula (4-1-6): Formula (4-1-1) Formula (4-1-2) Formula (4-1-3) Formula (4-1-4) Formula (4-1-5) Formula (4-1-6)

The diamine compound represented by the formula (4-2) is shown below: Formula (4-2) In formula (4-2), 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 compound (a2-4) represented by the above formula (4-2) is preferably a diamine compound represented by the following formula (4-2-1) to (4-2-13): Formula (4-2-1) Formula (4-2-2) Formula (4-2-9) Formula (4-2-10) Formula (4-2-11) Formula (4-2-12) Formula (4-2-13) In formulas (4-2-10) to (4-2-13), s may represent an integer of 3 to 12.

The diamine compound represented by the formula (4-3) is shown below: Formula (4-3) In formula (4-3), 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 an alkoxy group having 1 to 5 carbon atoms Radical or halogen, and X ₁₂ in each repeating unit may be the same or different. X ₁₃ is an integer from 1 to 3.

The diamine compound represented by the formula (4-3) is preferably selected from (1) X ₁₃ is 1: p-diaminebenzene, m-diaminebenzene, o-diaminebenzene or 2,5-diamine. Amine toluene, etc .; (2) X ₁₃ 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) X ₁₃ is 3: 1,4-bis (4'-aminophenyl) benzene, etc., and is more preferably selected from p-diaminebenzene, 2,5-diaminetoluene, 4,4'- Diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl or 1,4-bis (4'-aminophenyl) benzene.

The diamine compound represented by the formula (4-4) is shown below: Formula (4-4) In Formula (4-4), X ₁₄ represents an integer of 2 to 12.

The diamine compound represented by the formula (4-5) is shown below: Formula (4-5) In Formula (4-5), X ₁₅ represents an integer of 1 to 5. The formula (4-5) is preferably selected from 4,4'-diaminodiphenyl sulfide.

The diamine compound represented by the formula (4-6) is as follows: Formula (4-6) In formula (4-6), X ₁₆ and X ₁₈ may be the same or different, and each represents a divalent organic group, and X ₁₇ represents a derivative derived from pyridine, pyrimidine, triazine, piperidine, and Divalent groups such as piperazine having a nitrogen atom ring structure.

The diamine compound represented by the formula (4-7) is shown below: Formula (4-7) In formula (4-7), X ₁₉ , X ₂₀ , X _21, and X ₂₂ may be the same or different, and may represent a hydrocarbon group having 1 to 12 carbon atoms. X ₂₃ represents an integer from 1 to 3, and X ₂₄ represents an integer from 1 to 20.

The diamine compound represented by the formula (4-8) is as follows: Formula (4-8) In formula (4-8), X ₂₅ represents Or cyclohexyl, X ₂₆ represents -CH _2- , X ₂₇ represents phenyl or cyclohexane, and X ₂₈ represents a hydrogen atom or heptyl.

The diamine compound represented by the formula (4-8) is preferably selected from the diamine compounds represented by the following formulae (4-8-1) to (4-8-2): (4-8-1) (4-8-2)

The other diamine compounds represented by formula (4-9) to formula (4-25) are as follows: (4-9) (4-10) (4-11) (4-12) (4-13) (4-14) (4-15) (4-16) (4-21) (4-22) (4-23) (4-24) Formula (4-25) In formulas (4-17) to (4-25), X ₂₉ is preferably an alkyl group having 1 to 10 carbon atoms or an alkoxy group having 1 to 10 carbon atoms. X _{30 is} preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

The other diamine compound (a2-4) may preferably include, but is 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, formula (4 -1-1), formula (4-1-2), formula (4-1-5), formula (4-1-6), formula (4-2-1), formula (4-2-11) , P-diaminebenzene, m-diaminebenzene, o-diaminebenzene, and a compound represented by formula (4-8-1).

The aforementioned other diamine compounds (a2-4) can be used alone or in combination.

In a specific example of the present invention, the total amount of the diamine component (a2) used is 100 moles, and the amount of the other diamine compound (a2-4) is 0 to 97 moles, preferably 0 to 97 moles. 90 moles, more preferably 0 to 80 moles. [ Preparation method of polymer (A) ]

The polymer (A) may include at least one of a polyamidopolymer (A1) and a polyamidoimine polymer (A2). The polymer (A) may further include a polyfluorene-based block copolymer. The methods for preparing the various polymers described above are further described below. <Preparation method of polyamic acid polymer (A1)>

The method for preparing the polyamic acid polymer (A1) is firstly dissolving a first mixture in a solvent, wherein the first mixture includes a tetracarboxylic dianhydride component (a1) and a diamine component (a2), and The polycondensation reaction is performed at a temperature of 0 ° C to 100 ° C. After reacting for 1 hour to 24 hours, the reaction solution is distilled under reduced pressure using an evaporator to obtain polyamic acid. Alternatively, the reaction solution is poured into a large amount of a lean solvent to obtain a precipitate. Then, the precipitate is dried under reduced pressure to obtain polyamic acid.

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. The solvent preferably includes, but is not limited to (1) an aprotic polar solvent, such as: N-methyl-2-pyrrolidinone (NMP), N, N-dimethylacetamide, Aprotic polar solvents such as N, N-dimethylformamide, dimethylmethylene sulfonate, γ-butyrolactone, tetramethylurea or hexamethyl phosphate triamine; or (2) phenolic solvents, For example: m-cresol, xylenol, phenol or halogenated phenols. 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 based on the total use amount of the first mixture.

It is worth noting that 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 the polyamic acid to precipitate. The lean solvent can be used singly or in combination, and it includes but is 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 such as 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; or (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 use amount of the diamine component (a2) 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 weight average molecular weight of the polyamino acid polymer (A1) is 30,000 to 200,000; preferably 30,000 to 180,000; more preferably 30,000 to 150,000. <Preparation method of polyfluorene imine polymer (A2)>

The method for preparing the polyfluorene imine polymer (A2) is obtained by heating the polyphosphonic acid prepared by the method for preparing a polyphosphonium acid in the presence of a dehydrating agent and a catalyst. During the heating process, the arsenic acid functional group in the polyarsenic acid can be converted into the arsonimine functional group (ie, arsonimation) via a dehydration ring-closure reaction.

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

In order to obtain a better degree of polyimidation of the polyimide, 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 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 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, the amount of dehydrating agent used is 0.01 to 20 moles. The catalyst used in the dehydration ring-closing reaction may be selected from (1) pyridine compounds, such as pyridine, trimethylpyridine, or dimethylpyridine; and (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 can be 0.5 to 10 moles.

The polyfluorene imine polymer (A2) has a weight average molecular weight of 30,000 to 200,000; preferably 30,000 to 180,000; more preferably 30,000 to 150,000.

The fluorene imidization rate of the polymer (A) may be 30% to 80%, preferably 35% to 80%, and more preferably 35% to 75%. If the fluorenimidization ratio of the polymer (A) is within the above range, the adhesiveness of the liquid crystal alignment agent obtained is better. <Preparation method of polyfluorene-based block copolymers>

The polyimide-based block copolymer is selected from the group consisting of a polyimide block copolymer, a polyimide block copolymer, a polyimide-polyimide block copolymer, or the above-mentioned polymerization. Any combination of things.

The method for preparing a polyfluorene-based block copolymer is preferably firstly dissolving a starting material in a solvent and carrying out a polycondensation reaction, wherein the starting material includes at least one polyamic acid and / or at least one polyfluorene Imine, and may further include a carboxylic anhydride component and a diamine component.

The carboxylic acid anhydride component and the diamine component in the starting material may be the same as the tetracarboxylic dianhydride component (a1) and the diamine component (a2) used in the method for preparing a polyamic acid, and are used for The solvent in the polycondensation reaction may be the same as the solvent (C) in the liquid crystal alignment agent described below, and details are not described herein again.

The used 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 used 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.

The starting material preferably includes, but is not limited to, (1) two polyamido acids with different terminal groups and different structures; (2) two polyimines with different terminal groups and different structures; (3 ) Polyamidic acid and polyimide having different terminal groups and different structures; (4) Polyamidic acid, a carboxylic acid anhydride component, and a diamine component, among which the carboxylic acid anhydride component and the diamine component At least one of them is different from the structure of the carboxylic acid anhydride component and the diamine component used to form the polyamine acid; (5) the polyfluorene imine, the carboxylic acid anhydride component, and the diamine component, wherein the carboxylic acid anhydride group At least one of the component and the diamine component is different from the structure of the carboxylic acid anhydride component and the diamine component used to form the polyimide; (6) the polyamidic acid, the polyimide, and the carboxylic anhydride component And a diamine component, wherein at least one of the carboxylic acid anhydride component and the diamine component is different from the structure of the carboxylic acid anhydride component and the diamine component used to form the polyamic acid or polyimide; ( 7) Two kinds of polyfluorinated acid, carboxylic anhydride and diamine components with different structures; (8) Two kinds of polyfluorinated imine, carboxylic anhydride and diamine components with different structures; (9) Two terminal groups are acid anhydride groups and have structures Heteropolyamino acids and diamine components; (10) two kinds of polyamino acids and carboxylic anhydride components whose terminal groups are amine groups and different in structure; (11) two kinds of terminal groups are acid anhydride groups and structural phases Different polyimide and diamine components; or (12) two polyimide and carboxylic anhydride components whose terminal groups are amine groups and have different structures.

As long as the efficacy of the present invention is not affected, the polyamidic acid, polyamidoimide, and polyamidoimide block copolymer are preferably terminally modified polymers after molecular weight adjustment. 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 prepared by adding a polyfunctional compound while the polyamic acid is undergoing a polycondensation reaction.

Specific examples of monofunctional compounds include, but are not limited to (1) monobasic anhydrides, such as: maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecyl Monobasic anhydrides such as alkyl succinic anhydride or n-hexadecyl succinic anhydride; (2) monoamine compounds, such as: aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, N-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecanylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecanylamine, Monoamine compounds such as n-octadecylamine or n- eicosylamine; or (3) monoisocyanate compounds, such as monoisocyanate compounds such as phenyl isocyanate or naphthyl isocyanate.

The polysiloxane (B) includes an epoxy group-containing polysiloxane (b1) and a side chain compound (b2), and the epoxy group-containing polysiloxane (b1) includes A copolymer obtained by hydrolyzing and partially condensing a second mixture.

Wherein the epoxy group-containing polysiloxane (b1) contains at least one of the group represented by formula (III-1), the group represented by formula (III-2), and the group represented by formula (III-3) One.

Specifically, the group represented by formula (III-1) is shown below. Formula (III-1)

In formula (III-1), B represents an oxygen atom or a single bond; c represents an integer of 1 to 3; d represents an integer of 0 to 6; wherein when d represents 0, B is a single bond.

The group represented by formula (III-2) is shown below. Formula (III-2)

In Formula (III-2), e represents an integer of 0 to 6.

The radical represented by the formula (III-3) is shown below. Formula (III-3)

In formula (III-3), D represents a C ₂ to C ₆ alkylene group; E represents a hydrogen atom or a C ₁ to C ₆ alkyl group.

The epoxy group-containing group preferably includes a group represented by the formula (III-1-1), a group represented by the formula (III-2-1), and a group represented by the formula (III-3-1) At least one of them. Formula (III-1-1) Formula (III-2-1) Formula (III-3-1)

The epoxy group-containing polysiloxane (b1) of the present invention includes a copolymer obtained by subjecting a second mixture to hydrolysis and partial condensation, the second mixture including a silane monomer represented by formula (III-4) Body (b1-1); Si (R _f ) _b (OR _g ) _4-b Formula (III-4) In formula (III-4), R _f is a hydrogen atom, a C ₁ to C ₁₀ alkyl group, C ₂ to C ₁₀ alkenyl, C ₆ to C ₁₅ aryl, epoxy-containing alkyl group or epoxy-containing alkoxy group, and at least one R _f is epoxy-containing alkyl group or ring-containing the alkoxy group; when b is plural, R _f are each the same or different; R _g is a hydrogen atom, C ₁ to C ₆ alkyl group of, C ₁ to C ₆ acyl of C ₆ to C ₁₅ or An aryl group; when 4-b is plural, each R _g is the same or different; and b is an integer of 1 to 3.

In more detail, when R _f in the formula (III-4) represents an alkyl group of C ₁ to C ₁₀ , specifically, R _f is, for example, methyl, ethyl, n-propyl, isopropyl, n- Butyl, third butyl, n-hexyl or n-decyl. R _f may be an alkyl group having another substituent on the alkyl group. Specifically, R _{f is,} for example, trifluoromethyl, 3,3,3-trifluoropropyl, 3-aminopropyl, 3- Thiopropyl or 3-isocyanatopropyl.

When R _f in the formula (III-4) represents an alkenyl group of C ₂ to C ₁₀ , specifically, R _{f is,} for example, a vinyl group. R _f may be an alkenyl group having another substituent on the alkenyl group. Specifically, R _{f is,} for example, 3-propenyloxypropyl or 3-methacryloxypropyl.

When R _f in the formula (III-4) represents an aryl group of C ₆ to C ₁₅ , specifically, R _f is, for example, a phenyl group, a tolyl group, or a naphthyl group. R _f may be an aryl group having another substituent on the aryl group. Specifically, R _f is, for example, p-hydroxyphenyl, 1- (p-hydroxyphenyl) ethyl (1 -(o-hydroxyphenyl) ethyl), 2- (p-hydroxyphenyl) ethyl (2- (o-hydroxyphenyl) ethyl) or 4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyl ( 4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyl).

When R _f in formula (III-4) represents an epoxy-containing alkyl group or an epoxy-containing alkoxy group, a specific example of R _f is the aforementioned epoxy-containing polysiloxane ( b1) contains epoxy groups, which will not be repeated here.

In addition, when R _{g of the} formula (III-4) represents a C ₁ to C ₆ alkyl group, specifically, R _g is, for example, methyl, ethyl, n-propyl, isopropyl, or n-butyl. When R _g in the formula (III-4) represents a fluorenyl group of C ₁ to C ₆ , specifically, R _{g is,} for example, an ethenyl group. When R _g in the formula (III-4) represents an aryl group of C ₆ to C ₁₅ , specifically, R _{g is,} for example, a phenyl group.

Specific examples of the silane monomer (b1-1) include 3- (N, N-diglycidyl) aminopropyltrimethoxysilane, and 3- (N-allyl-N-glycidyl) amino group. Propyltrimethoxysilane, 3-glycidyletherpropyltrimethoxysilane, 3-glycidyletherpropyltriethoxysilane, 3-glycidyletherpropylmethyldimethoxysilane, 3-glycidyl ether propylmethyldiethoxysilane, 3-glycidyl ether propyldimethylmethoxysilane, 3-glycidyl ether propyldimethylethoxysilane, 2- Glycidyl ether ethyltrimethoxysilane, 2-glycidyl ether ethyltriethoxysilane, 2-glycidyl ether ethylmethyldimethoxysilane, 2-glycidyl ether ethylmethyl Didiethoxysilane, 2-glycidyl ether ethyl dimethylmethoxysilane, 2-glycidyl ether ethyl dimethyl ethoxysilane, 4-glycidyl ether butyl trimethoxy Silane, 4-glycidyl ether butyl triethoxy silane, 4-glycidyl ether butyl methyl dimethoxy silane, 4-glycidyl ether butyl methyl diethoxy silane, 4-glycidyl ether Butyl Methylmethoxysilane, 4-glycidyl ether butyl dimethylethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-cyclo Oxycyclohexyl) ethyltriethoxysilane, 3- (3,4-epoxycyclohexyl) propyltrimethoxysilane, 3- (3,4-epoxycyclohexyl) propyltriethoxysilane ((3-ethyl-3-glycidyl) methoxy) propyltrimethoxysilane, ((3-ethyl-3-glycidyl) methoxy) propyltriethoxy Silane, ((3-ethyl-3-glycidyloxy) methoxy) propylmethyldimethoxysilane or ((3-ethyl-3-glycidyl) methoxy) propanedi Methylmethoxysilane, commercially available products such as DMS-E01, DMS-E12, DMS-E21, EMS-32 (manufactured by JNC), or a combination of the aforementioned compounds.

Specific examples of the silane monomer (b1-1) represented by the formula (III-4) include 3-glycidyl ether propyltrimethoxysilane, 2-glycidyl ether ethyltrimethoxysilane, 4 -Glycidyl ether butyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane ((3-ethyl-3-glycidyl) methoxy) propyltrimethoxysilane, ((3-ethyl-3-glycidyl) methoxy) propyltriethoxy Silane, DMS-E01, DMS-E12, or a combination of these compounds.

Based on the total amount of monomers in the second mixture being 1 mole, the amount of the silane monomer (b1-1) used is 0.6 to 1 mole, preferably 0.65 to 1 mole, more It is preferably 0.7 to 1 mole.

The second mixture for reacting to form the epoxy-containing polysiloxane (b1) preferably further contains another silane monomer (b1-2) represented by formula (III-5): Si (R _h ) and _f (OR _{i) 4-f} of formula (III-5) of formula (III-5), R _h is a hydrogen atom, C ₁ to C ₁₀ alkyl group of, C ₂ to C ₁₀ alkenyl group of, C ₆ to C ₁₅ aryl group or alkyl group containing acid anhydride group; when f is plural, R _h are each the same or different; R _i is hydrogen atom, C ₁ to C ₆ alkyl group, C ₁ to C ₆ alkyl group Or C ₆ to C ₁₅ aryl; when 4-f is plural, each R _i is the same or different; and f is an integer from 1 to 3.

When R _h in formula (III-5) represents a C ₁ to C ₁₀ alkyl group, a C ₂ to C ₁₀ alkenyl group, and a C ₆ to C ₁₅ aryl group, specific examples and preferred examples thereof include the aforementioned R _f As shown, it will not be repeated here.

When _Rh in the formula (III-5) represents an alkyl group containing an acid anhydride group, the alkyl group is preferably a C ₁ to C ₁₀ alkyl group. Specifically, the acid-anhydride-containing alkyl group is, for example, ethylsuccinic anhydride represented by formula (III-5-1), propylsuccinic anhydride represented by formula (III-5-2), or formula ( III-5-3). It is worth mentioning that the acid anhydride group is a group formed by dicarboxylic acid by intramolecular dehydration. The dicarboxylic acid is, for example, succinic acid or glutaric acid. Formula (III-5-1) Formula (III-5-2) Formula (III-5-3)

When R _i in formula (III-5) represents a C ₁ to C ₆ alkyl group, a C ₁ to C ₆ fluorenyl group, or a C ₆ to C ₁₅ aryl group, specific examples and preferred examples thereof include the aforementioned R _g As shown, it will not be repeated here.

The other silane monomer (b1-2) represented by the formula (III-5) may be used alone or in combination, and the other silane monomer (b1-2) represented by the formula (III-5) contains one having a silicon atom. Compound. The compound having one silicon atom includes a silane compound having four hydrolyzable groups, a silane compound having three hydrolyzable groups, a silane compound having two hydrolyzable groups, and a silane having one hydrolyzable group. Compound, or a combination thereof.

Specific examples of the silane compound having four hydrolyzable groups include tetrachlorosilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, and tetra-n-butoxysilane , Tetra-second butoxysilane, or a combination thereof.

Specific examples of the silane compound having three hydrolyzable groups include methyltrimethoxysilane (MTMS for short), methyltriethoxysilane, methyltriisopropoxysilane, methyltriisosilane Methyltri-n-butoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, ethyltriisopropoxysilane, ethyl Tri-n-butoxysilane (n-propyltrimethoxysilane), n-propyltrimethoxysilane, n-propyltriethoxysilane, n-butyltriethoxysilane (n -butyltrimethoxysilane), n-butyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, decyltrimethoxysilane decyltrimethoxysilane), vinyltrimethoxysilane, vinyltriethoxysilane, 3-propenyloxypropyl 3-acryoyloxypropyltrimethoxysilane, 3-methylacryloyloxypropyltrimethoxysilane (MPTMS), 3-methylacryloyloxypropyltrimethoxysilane (3-methylacryloyloxypropyltrimethoxysilane) methylacryloyloxypropyltriethoxysilane), phenyltrimethoxysilane (PTMS), phenyltriethoxysilane (PTES), p-hydroxyphenyltrimethoxysilane, 1- (p-hydroxybenzene (1- (p-hydroxyphenyl) ethyltrimethoxysilane), 2- (p-hydroxyphenyl) ethyltrimethoxysilane, 4-hydroxy-5 -(P-hydroxyphenylcarbonyloxy) pentyltrimethoxysilane (4-hydroxy-5- (p-hydroxyphenylcarbonyloxy) pentyltrimethoxysilane), trifluoromethyltrimethoxysilane, trifluoromethyltrimethoxysilane Trifluoromethyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3-aminopropyltrimethoxysilane methoxysilane), 3-aminopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3- (triphenoxysilyl) propylsuccinic anhydride ( 3-triphenoxysilyl propyl succinic anhydride), a commercially available product manufactured by Shin-Etsu Chemical Co., Ltd .: 3- (trimethoxysilyl propyl succinic anhydride) (trade name X-12-967), Commercial products manufactured by WACKER: 3- (triethoxysilyl) propyl succinic anhydride (trade name: GF-20), 3- (trimethoxysilyl) (3- (trimethoxysilyl) propyl glutaric anhydride (TMSG), 3- (triethoxysilyl) propyl glutaric anhydride), 3- (trimethoxysilyl) 3- (triphenoxysilyl) propyl glutaric anhydride) or a combination thereof.

Specific examples of the silane compound having two hydrolyzable groups include methyldimethoxysilane, methyldiethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, methyl [2- (perfluoro-n-octyl) ethyl] dimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, diphenyldimethoxysilane, dimethyldiethoxysilane , Di-n-butyldimethoxysilane, or a combination thereof.

Specific examples of the silane compound having one hydrolyzable group include methoxydimethylsilane, methoxytrimethylsilane, methoxymethyldiphenylsilane, tri-n-butylethoxysilane, or A combination of the above compounds.

The other silane monomer (b1-2) of the structure represented by the formula (III-5) is preferably tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, Phenyltrimethoxysilane, phenyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, thiomethyltrimethoxysilane, thiomethyltriethoxy Silane, dimethyldimethoxysilane, dimethyldiethoxysilane, or a combination of these compounds.

Based on the total amount of the monomers in the second mixture being 1 mole, the usage amount of the silane monomer (b1-2) is 0 to 0.7 moles, preferably 0 to 0.6 moles, more It is preferably 0 to 0.5 mole.

The second mixture may further include a commercially available silane monomer, and specific examples thereof include KC-89, KC-89S, X-21-3153, X-21-5841, X-21-5842, and X-21-5843. , X-21-5844, X-21-5845, X-21-5846, X-21-5847, X-21-5848, X-22-160AS, X-22-170B, X-22-170BX, X -22-170D, X-22-170DX, X-22-176B, X-22-176D, X-22-176DX, X-22-176F, X-40-2308, X-40-2651, X-40 -2655A, X-40-2671, X-40-2672, X-40-9220, X-40-9225, X-40-9227, X-40-9246, X-40-9247, X-40-9250 , X-40-9323, X-41-1053, X-41-1056, X-41-1805, X-41-1810, KF6001, KF6002, KF6003, KR212, KR-213, KR-217, KR220L, KR242A KR271, KR282, KR300, KR311, KR401N, KR500, KR510, KR5206, KR5230, KR5235, KR9218, KR9706 (made by Shin-Etsu Chemical); glass resin (GLASS RESIN, manufactured by Showa Denko); SH804, SH805, SH806A, SH840, SR2400 , SR2402, SR2405, SR2406, SR2410, SR2411, SR2416, SR2420 (made by Toray Dow Corning); FZ3711, FZ3722 (made by NUC); DMS-S12, DMS-S15, DMS-S21, DMS-S27, DMS-S31, DMS -S32, DMS-S33, DMS-S35, DMS-S38, DMS-S42 , DMS-S45, DMS-S51, DMS-227, PSD-0332, PDS-1615, PDS-9931, XMS-5025 (made by JNC); MS51, MS56 (made by Mitsubishi Chemical); and GR100, GR650, GR908, GR950 (Manufactured by Showa Denko) and other condensates.

The epoxy group-containing polysiloxane (b1) contains an epoxy group such as a glycidyl group, a glycidyloxy group, an epoxycyclohexyl group, or propylene oxide Radical (oxetanyl group). [ Preparation method of epoxy group-containing polysiloxane (b1) ]

The polycondensation reaction of the epoxy group-containing polysiloxane compound can be formed by a general method. For example, an organic solvent, water, or a catalyst is optionally further added to the silane compound or a mixture thereof, and then an oil bath is used. The heating is performed at 50 ° C to 150 ° C, and the heating time is preferably 0.5 hours to 120 hours. During heating, the mixed solution may be stirred or placed under reflux conditions.

The organic solvent is not particularly limited, and may be the same as or different from the solvent (C) contained in the liquid crystal alignment agent of the present invention.

Specific examples of the organic solvent include hydrocarbon compounds such as toluene and xylene; methyl ethyl ketone, methyl isobutyl ketone, methyl n-pentyl ketone, diethyl ketone, cyclohexanone, and 2-butanone , 2-hexanone and other ketone solvents; ethyl acetate, n-butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, ethyl lactate and other esters Solvents; Ether solvents such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, dioxane (dioxane); 1-hexanol, 4-methyl 2-pentanol, ethylene glycol mono Methyl ether, ethylene 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, etc. Alcohol solvents; N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, trimethylamine hexamethyl phosphate, 1,3-dimethyl Amidamine-based solvents such as 2-imidazolidinone, or a combination of the above organic solvents.

These organic solvents may be used alone or in combination.

The use amount of the organic solvent is preferably 10 to 1200 parts by weight, and more preferably 30 to 1000 parts by weight, based on 100 parts by weight of all the silane compounds.

The hydrolyzable group is 1 mol based on all the silane compounds, and the amount of water used is preferably 0.5 mol to 2 mol.

The catalyst is not particularly limited. Preferably, the catalyst is selected from the group consisting of an acid, an alkali metal compound, an organic base, a titanium compound, a zirconium compound, or a combination thereof.

Specific examples of the acid include hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, trifluoroacetic acid, formic acid, polycarboxylic acid, polybasic acid anhydride, or a combination thereof.

Specific examples of the alkali metal compound include sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, or a combination thereof.

Specific examples of the organic base include primary or secondary organic amines such as ethylamine, diethylamine, piperazine, piperidine, pyrrolidine, and pyrrole; triethylamine, triethylamine Tertiary organic amines such as n-propylamine, tri-n-butylamine, pyridine, 4-dimethylaminopyridine, diazabicycloundecene, and other tertiary organic amines such as tetramethylammonium hydroxide Amines, etc., or a combination of the above.

The amount of catalyst used varies depending on the reaction conditions such as type, temperature, etc., and can be appropriately set. For example, based on 1 mol of all silane compounds, the addition amount of the catalyst is 0.01 mol to 5 mol, preferably 0.03 to 3 mol, more preferably 0.05 to 1 mol.

From the viewpoint of stability, after the completion of the polycondensation reaction, the organic solvent layer fractionated from the reaction liquid 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. 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 organic solvent is removed to obtain an epoxy group-containing Polysiloxane (b1).

When the polysiloxane (B) is not used with an epoxy-containing polysiloxane (b1) or the used polysiloxane (b1) does not contain an epoxy group, then the Poor environmental resistance and poor adhesion.

The side chain compound (b2) of the present invention includes a structure represented by formula (IV): E ¹ -L ⁰ -L ¹ -Z Formula (IV) In formula (IV), E ¹ is a C ₁ to C ₃₀ alkane A C ₁ to C ₂₀ alkyl or alkoxy group, or a C ₃ to C ₁₀ cycloalkyl group, or a C ₁₇ to C ₅₁ hydrocarbon group containing a steroid skeleton, the E ¹ alkyl group And part of the alkoxy group is substituted or unsubstituted; L ⁰ is a single bond, * -O- *, * -COO- * or * -OCO- *; L ¹ is a single bond, C ₁ to C ₂₀ Alkylene, phenylene, phenylene, cyclohexyl, dicyclohexyl or a group represented by the following formula (IV-1) or (IV-2): Formula (IV-1) Formula (IV-2) When L ¹ is a single bond, L ⁰ is a single bond; * is a bond; and Z is a monovalent organic group that reacts with an epoxy group to form a bonding group.

The linear or branched C ₁ to C ₃₀ alkyl group described by E ^{1 in} the above formula (IV) may be, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, second butyl, third butyl, n-pentyl, 3-methylbutyl, 2-methylbutyl, 1-methylbutyl, 2,2-dimethylpropyl , N-hexyl, 4-methylpentyl, 3-methylpentyl, 2-methylpentyl, 1-methylpentyl, 3,3-dimethylbutyl, 2,3-dimethyl Butyl, 1,3-dimethylbutyl, 2,2-dimethylbutyl, 1,2-dimethylbutyl, 1,1-dimethylbutyl, n-heptyl, 5 -Methylhexyl, 4-methylhexyl, 3-methylhexyl, 2-methylhexyl, 1-methylhexyl, 4,4-dimethylpentyl, 3,4-dimethylpentyl, 2 , 4-dimethylpentyl, 1,4-dimethylpentyl, 3,3-dimethylpentyl, 2,3-dimethylpentyl, 1,3-dimethylpentyl, 2 2,2-dimethylpentyl, 1,2-dimethylpentyl, 1,1-dimethylpentyl, 2,3,3-trimethylbutyl, 1,3,3-trimethyl Butyl, 1,2,3-trimethylbutyl, n-octyl, 6-methylheptyl, 5-methylheptyl, 4-methylheptyl, 3-methylheptyl, 2- Methylheptyl, 1-methylheptyl, 2-ethylhexyl, n-nonyl , N-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-hexadecyl, n- Eighteen bases, n-nineteen bases, etc.

The C ₃ to C ₁₀ cycloalkyl group described by E ^{1 in} the above formula (IV) may be, for example, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl Wait. These cycloalkyl groups described above may be substituted with or without C ₁ to C ₂₀ alkoxy groups. For specific examples of the C ₁ to C ₂₀ alkoxy group, reference may be made to the specific examples given in the description of the C ₁ to C ₃₀ alkyl group described above. For specific examples of the C ₁ to C ₂₀ alkoxy group, reference may be made to the specific examples of the alkyl group mentioned in the description of the C ₁ to C ₃₀ alkyl group, and the group obtained by bonding with an oxygen atom. The alkyl group and the alkoxy group described in E ¹ may have at least a part of hydrogen atoms substituted, and examples of the group for replacing a hydrogen atom include a nitrile group, a fluorine atom, and a trifluoromethyl group.

The hydrocarbon group of C ₁₇ to C ₅₁ containing a steroid skeleton as described in E ^{1 in} the above formula (IV) may be, for example, a group represented by the following formulae (S-1) to (S-3), wherein * 5 represents a bond between the above group and L ⁰ of formula (IV). Formula (S-1) Formula (S-2) Formula (S-3)

Preferably, E ¹ may be selected from C ₁ to C ₂₀ alkyl groups, C ₁ to C ₂₀ fluoroalkyl groups, groups of the above formula (S-1), and groups of the above formula (S-3) A group of people. Z is preferably a carboxyl group. The alkylene group of C ₁ to C ₂₀ described in L ^{1 in} the above formula (IV) may be, for example, removing one hydrogen atom from each of the groups mentioned in the aforementioned alkyl group of C ₁ to C ₃₀ And the resulting group.

The compound represented by the above formula (IV) is preferably a compound represented by the following formulae (IV-1) to (IV-8). Formula (IV-1) Formula (IV-2) Formula (IV-3) Formula (IV-4) Formula (IV-5) Formula (IV-6) Formula (IV-7) Formula (IV-8)

In formulae (IV-1) to (IV-8), u is an integer from 1 to 5, v is an integer from 1 to 18, w is an integer from 1 to 20, k is an integer from 1 to 5, and p is 0 or 1. q is an integer from 1 to 18, r is an integer from 0 to 18, and j is an integer from 1 to 18. s and t are each independently an integer of 0 to 2. However, s and t are not 0 at the same time.

Preferably, v in the above formula (IV-1) is an integer of 1 to 18, but an integer of 1 to 12 is more preferable. W of the above formula (IV-2) is preferably an integer of 5 to 20, and more preferably 10 to 18. W of the above formula (IV-3) may be an integer of 1 to 17, but an integer of 3 to 12 is more preferable. W of the above formula (IV-4) is preferably an integer of 1 to 15, but an integer of 1 to 8 is more preferable. W of the above formula (IV-8) is preferably an integer of 1 to 15, but an integer of 1 to 8 is more preferable. In the above formulae (IV-5) and (IV-6), r is preferably an integer of 0 to 15, but an integer of 0 to 8 is more preferable. In the above formula (IV-6), q may be an integer of 1 to 12, but an integer of 1 to 5 is more preferable. J in the above formula (IV-8) is preferably an integer of 1 to 15, but an integer of 1 to 8 is more preferable.

Among the above compounds, at least one of the above formulae (IV-2) to (IV-5), (IV-7), and (IV-8) is preferable. Specifically, the following formulae (IV-1 ') to (IV-8') are preferred. Formula (IV-1 ') Formula (IV-2 ') Formula (IV-3 ') Formula (IV-4 ') Formula (IV-5 ') Formula (IV-6 ') Formula (IV-7 ') Formula (IV-8 ')

When the polysiloxane (B) is not used with the side chain compound (b2), the obtained liquid crystal alignment agent has poor environmental resistance and poor adhesion.

Based on the total amount of monomers in the second mixture being 1 mole, the amount of the side chain compound (b2) used is 0.05 to 0.5 mole, preferably 0.1 to 0.45 mole, and 0.2 mole Ears to 0.4 moles are more preferred. If the use amount of the side chain compound (b2) is within the above range, the obtained liquid crystal alignment agent has better environmental resistance.

Based on 100 parts by weight of the polymer (A) and 1 to 30 parts by weight of the polysiloxane (B), preferably 1 to 28 parts by weight, and 1 part by weight It is more preferably 25 parts by weight. [ Preparation method of polysiloxane (B) ]

The polysiloxane (B) used in the present invention can be synthesized by reacting the epoxy group-containing polysiloxane (b1) and a side chain compound (b2) in the presence of a catalyst.

As the catalyst, an organic salt or a known compound such as a hardening accelerator that can accelerate the reaction between the epoxy compound and the acid anhydride can be used.

Examples of the organic salt include primary or secondary organic amines such as ethylamine, diethylamine, piperazine, piperidine, pyrrolidine, and pyrrole; triethylamine, tri-n-propylamine, and tri-n-butylamine. Tertiary organic amines such as amines, pyridine, 4-dimethylaminopyridine, diazabicycloundecene, and tertiary organic amines such as tetramethylammonium hydroxide. Among these organic amines, tertiary organic amines such as triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, and 4-dimethylaminopyridine, or tetramethylammonium hydroxide, etc. are preferred. Grade organic amine.

Specific examples of the hardening accelerator include tertiary amines such as benzyldimethylamine, 2,4,6-tris (dimethylaminomethyl) phenol, cyclohexyldimethylamine, and triethanolamine; Imidazole, 2-n-heptylimidazole, 2-n-alkylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl- 2-phenylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1- (2-cyanoethyl) -2-methylimidazole, 1- (2-cyano (Ethyl) -2-5-n-undecylimidazole, 1- (2-cyanoethyl) -2-phenylimidazole, 1- (2-cyanoethyl) -2-ethyl-4- Methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-bis (hydroxymethyl) imidazole, 1- (2-cyanoethyl) -2 -Phenyl-4,5-bis [(2'-cyanoethoxy) methyl] imidazole, l- (2-cyanoethyl-2-n-undecylimidazolium trimellitate , 1- (2-cyanoethyl) -2-phenylimidazolium trimellitate, 1- (2-cyanoethyl) -2-ethyl-4-methylimidazolium trimellitic acid Salt, 2, 4-diamino-6- [2'-methylimidazolyl- (1 ')] ethyl-S-triazine, 2,4-diamino-6- (2'-n-deca Monoalkylimidazole) ethyl-S-triazine, 2,4-diamino-6- [2'- -4'-methylimidazolyl- (1 ')] ethyl-S-triazine, trimeric isocyanate adduct of 2-methylimidazole, triphenyl isocyanate addition of 2-phenylimidazole Imidazole compounds such as trimeric isocyanate adducts of 2,4-diamino-6- [2'-methylimidazolyl- (1 ')] ethyl-S-triazine; diphenyl Organophosphorus compounds such as phosphine, triphenylphosphine, and triphenyl phosphite; benzyl triphenylphosphonium chloride, tetra-n-butylphosphonium bromide, methyltriphenylphosphonium bromide, Ethyltriphenylphosphonium bromide, n-butyltriphenylphosphonium bromide, tetraphenylphosphonium bromide, ethyltriphenylphosphonium iodide, ethyltriphenylphosphonium acetate, tetra-n-butylphosphonium acetate- O, O-diethyl phosphorodithiosulfate (tetra-n-butyl phosphonium-O, O-diethyl phosphorodithionate), tetra-n-butylphosphonium benzotriazole salt (tetra-n-butylphosphonium benzotriazolate), tetra Tertiary phosphonium salts such as n-butylphosphonium tetrafluoroborate, tetra-n-butylphosphonium tetraphenylborate, tetraphenylphosphonium tetraphenylborate, etc .; 1,8-diazabicyclo [5.4.0] Diazabicyclic olefins such as monoene-7 or its organic acid salts; zinc octoate, tin octoate, acetamidine Organometallic compounds such as aluminum acetylacetone complex; tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride, tetra-n-butylammonium chloride, etc. Grade ammonium salts; boron compounds such as boron trifluoride and triphenyl borate; metal halogen compounds such as zinc chloride and tin tetrachloride; dicyandiamide or the addition of amines and epoxy resins Latent hardening accelerators with high melting point dispersion, such as amine addition molding accelerators such as products; microcapsules that cover the surface of the hardening accelerators such as imidazole compounds, organic phosphorus compounds, or quaternary phosphonium salts with polymers Latent Hardening Accelerator; Amine Salt Latent Hardening Accelerator; Lactoacid, Bronsted Acid Salt, and other high-temperature dissociation-type thermal cationic polymerization latent hardening accelerator, etc. Wait.

Specific examples of the hardening accelerator are preferably quaternary ammonium salts such as tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride, and tetra-n-butylammonium chloride.

Specific examples of the hardening accelerator are preferably quaternary ammonium salts such as tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride, and tetra-n-butylammonium chloride.

The reaction temperature is preferably 0 ° C to 200 ° C, and more preferably 50 ° C to 150 ° C. The reaction time is preferably from 0.1 to 50 hours, and more preferably from 0.5 to 20 hours.

The synthesis reaction of polysiloxane (B) can be performed in the presence of an organic solvent as needed. The organic solvent is not particularly limited, and may be the same as or different from the organic solvent used in the preparation of the epoxy-containing polysiloxane (b1) and the solvent (C) contained in the liquid crystal alignment agent of the present invention. the same. Specific examples of the organic solvent are preferably 2-butanone, 2-hexanone, methyl isobutyl ketone, n-butyl acetate, or a combination thereof.

The polysiloxane (B) of the present invention has a weight average molecular weight of 2,000 to 20,000; preferably 3,000 to 18,000; more preferably 5,000 to 15,000.

The solvent used in the liquid crystal alignment agent of the present invention is not particularly limited, as long as it dissolves the polymer (A), the polysiloxane (B) and other arbitrary components and does not react therewith, it is preferably The same solvents as those used in the synthesis of the polyamic acid may be used together with the lean solvents used in the synthesis of the polyamino acid.

Specific examples of the solvent (C) include, but are not limited to, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, 4-hydroxy-4-methyl-2-pentanone, and 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 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 Or N, N-dimethylformamide or N, N-dimethyl acetamide. The solvent (C) may be used alone or in combination.

Based on 100 parts by weight of the polymer (A), 500 to 3000 parts by weight of the solvent (C) is used, preferably 800 to 3000 parts by weight, and more preferably 800 to 2500 parts by weight.

To the extent that the efficacy of the present invention is not affected, the liquid crystal alignment agent may optionally add an additive (D), wherein the additive (D) includes a compound having at least two epoxy groups, a silane compound having a functional group, Or a combination.

Compounds having at least two epoxy groups include, but are 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, glycerol diglycidyl ether, 2,2-di Bromo neopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl- M-xylylenediamine, 1,3-bis (N, N-glycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4 '-Diaminodiphenylmethane, 3- (N, N-diepoxypropyl) aminopropyltrimethoxysilane, or a combination of the above compounds.

The compound having at least two epoxy groups may be used alone or in combination.

The use amount of the compound having at least two epoxy groups may be 0 to 40 parts by weight, and preferably 0.1 to 30 parts by weight based on the use amount of the polymer (A).

Specific examples of the silane compound having a functional group include, but are not limited to, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2 -Aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyl Dimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxy Silyl, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylene Triamine, 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 N-phenyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis ( Ethylene) -3-aminopropyl trimethoxy Silane, N- bis (oxyethylene) -3-aminopropyl triethoxysilane Silane, or combinations of the above compounds.

The silane compound having a functional group 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 silane compound having a functional group may be 0 to 10 parts by weight, and preferably 0.5 to 10 parts by weight.

The use amount of the additive (D) is preferably 0.5 to 50 parts by weight, and more preferably 1 to 45 parts by weight based on the total use amount of the polymer (A). [ Manufacturing method of liquid crystal alignment agent ]

The method for preparing the liquid crystal alignment agent of the present invention is not particularly limited, and it can be prepared by a general mixing method. For example, the polymer (A) and the polysiloxane (B) prepared in the above manner are first mixed uniformly to form a mixture. Next, the solvent (C) is added under the condition of a temperature of 0 ° C. to 200 ° C., and the additive (D) is optionally added. Finally, the stirring is continued with a stirring device until dissolved. In addition, it is preferable to add the solvent (C) at a temperature of 20 ° C to 60 ° C.

At 25 ° C, the viscosity of the liquid crystal alignment agent of the present invention is usually 15 cps to 35 cps, preferably 17 cps to 33 cps, and more preferably 20 cps to 30 cps. [ Manufacturing method of liquid crystal alignment film and liquid crystal display element ]

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 liquid crystal alignment film of the present invention is formed by using the liquid crystal alignment agent prepared as described above. The liquid crystal display element of the present invention includes a liquid crystal alignment film formed of the liquid crystal alignment agent. The operation mode of the liquid crystal display element is not particularly limited, and it may be a vertical alignment type.

The liquid crystal alignment film and the method for manufacturing a liquid crystal display element of the present invention may include: coating the liquid crystal alignment agent of the present invention on a pair of conductive films of a substrate having a conductive film, and heating the substrate to form a coating film The first step; the second step of arranging the pair of substrates with the coating film formed thereon to construct a liquid crystal cell; and arranging the pair of substrates with a conductive film with light when the voltage is applied to the liquid crystal cell The third step. [First Step: Formation of Coating Film]

In this step, two substrates provided with a patterned transparent conductive film are used as a pair, and the liquid crystal alignment agent of the present invention is coated on the surface of the substrate on which the transparent conductive film is formed, preferably a lithographic plate The liquid crystal alignment agent is applied by a printing method, a spin coating printing method, a roll coating method, or an inkjet method. The substrate referred to here may be, for example, glass such as float glass, soda glass; polyethylene terephthalate, polybutylene terephthalate, polyether, polycarbonate, poly (alicyclic olefin) And other plastic transparent substrates. The transparent conductive film provided on the surface of the substrate can be a NESA film (registered trademark of PPG, USA) formed of tin oxide (SnO ₂ ), or an indium oxide and tin oxide (In ₂ O ₃ -SnO ₂ ). ITO film. The patterned transparent conductive film can be formed by, for example, first forming an unpatterned transparent conductive film, then photo-etching a pattern forming method, and using a mask having a predetermined pattern when the transparent conductive film is formed. Reached. When applying the liquid crystal alignment agent, in order to provide good adhesion between the substrate surface and the transparent conductive film and the coating film, the surface of the substrate on which the coating film is formed may be previously coated with a functional silane compound and a functional titanium compound. Wait before processing.

After the liquid crystal alignment agent is applied, in order to prevent the applied liquid crystal alignment agent from dripping, it is preferable to perform prebake. The pre-baking temperature may be 30 ° C to 200 ° C, preferably 40 ° C to 150 ° C, and more preferably 40 ° C to 100 ° C. The pre-baking time may be from 0.25 to 10 minutes, preferably from 0.5 to 5 minutes. After that, the solvent is completely removed, and the substrate is subjected to a step of sintering (post-baking) in order to form the necessary polymer and the structure of the amino acid to be thermally imidized. The post-baking temperature may be 80 ° C to 300 ° C, preferably 120 ° C to 250 ° C. The post-baking time may be 5 minutes to 200 minutes, preferably 10 minutes to 100 minutes. Therefore, the thickness of the formed film may be 0.001 μm to 1 μm, and preferably 0.005 μm to 0.5 μm.

The heating step after the liquid crystal alignment agent is applied can remove the organic solvent, thereby forming a coating film of the liquid crystal alignment film. At this time, the polymer contained in the liquid crystal alignment agent of the present invention includes a polyfluorene acid or a fluorene imine polymer having a fluorene imine structure and a fluorin acid structure. Thereafter, the formed coating film is further heated, and the polymer undergoes a dehydration ring-closing reaction to form a fluorinated coating film. The coating film formed by the above method can be directly used as a liquid crystal alignment film, but a predetermined rubbing treatment can also be performed. [Second step: construction of liquid crystal cells]

In this step, two substrates on which the above-mentioned liquid crystal alignment film is formed are provided, and a liquid crystal layer containing a liquid crystal compound and a photopolymerizable compound is disposed between the two substrates disposed oppositely to form a liquid crystal cell. Examples of the method for manufacturing the liquid crystal cell include the following two methods.

The first method is a conventional method (vacuum injection method). First, two substrates are arranged opposite to each other so that a gap (cell gap; Cell Gap) is formed between the oppositely arranged liquid crystal alignment films. The two substrates are bonded together with an adhesive, and a liquid crystal compound and a photopolymerizable compound are injected and filled in a cell gap defined by the substrate surface and the adhesive, and then the injection holes are sealed to obtain a liquid crystal. Cell.

The second method is called One Drop Filling (ODF). For example, a UV-curable adhesive is applied to a predetermined place on one of the two substrates on which the liquid crystal alignment film is formed. Next, after a mixture of a liquid crystal compound and a photopolymerizable compound is dropped at a predetermined position of the liquid crystal alignment film, the liquid crystal alignment film and the liquid crystal alignment film of the other substrate are disposed opposite to each other, and the two substrates are bonded together so that the liquid crystal is on the substrate. Diffuses over the entire surface, and then irradiates the entire substrate with ultraviolet light to harden the adhesive to produce liquid crystal cells. Regardless of which method is used, after the liquid crystal cell is formed, the substrate is heated to a temperature at which the liquid crystal compound used is converted to an isotropic temperature, and then slowly cooled to room temperature to remove the flow alignment during liquid crystal filling.

As the above-mentioned adhesive, an epoxy resin as a hardener and a spacer can be used, which contains alumina balls. The liquid crystal compound is preferably a nematic liquid crystal having negative dielectric anisotropy. For example, dicyanophenyl liquid crystal, pyridazine liquid crystal, Schiff base liquid crystal, azo oxide liquid crystal, and biphenyl liquid crystal can be used. , Phenylcyclohexyl liquid crystal, terphenyl liquid crystal and the like. In addition, in order to make the response speed of the liquid crystal display device of the PSA mode faster, it is preferable to use an alkenyl liquid crystal in combination, which is a monofunctional liquid crystal compound having one alkenyl or fluoroalkenyl group. As the alkenyl liquid crystal, a conventional alkenyl liquid crystal can be used, for example, a compound represented by the following formula (L1-1) to formula (L1-9).

As the photopolymerizable compound, a compound having a functional group capable of performing a radical polymerization reaction, such as an acryl group, a methacryl group, or a vinyl group, can be used. Among these, from the viewpoint of reactivity, a compound having a functional group of at least two of an acrylamide group and a methacryl group is preferably used. In addition, from the viewpoint of maintaining the alignment stability of the liquid crystal molecules, the photopolymerizable compound is a liquid crystal skeleton, and a compound having at least two of a cyclohexane ring and a benzene ring is preferably used. As the photopolymerizable compound, a conventional photopolymerizable compound can be used. The photopolymerizable compound is preferably used in an amount of 0.1% to 0.5% by weight based on the entire weight of the liquid crystal compound. The thickness of the liquid crystal layer is preferably 1 μm to 5 μm. [Third step: exposure step]

After the liquid crystal cell is constructed, a voltage is applied between the conductive films of the pair of substrates, and at the same time, light is irradiated. The voltage applied here can be, for example, 5V to 50V DC or AC. In addition, the irradiated light may be, for example, ultraviolet light and visible light including light having a wavelength of 150 nm to 800 nm, but ultraviolet light including light having a wavelength of 300 nm to 400 nm is more preferable. As a light source for irradiating light, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, and the like can be used. In addition, a light source can be used in combination with a filter, a diffraction grating, and the like to obtain the above-mentioned ultraviolet light in the preferred wavelength range.

The irradiation amount of light may be 1,000 J / m ² or more and less than 100,000 J / m ² , and preferably 1000 J / m ² to 50,000 J / m ² . For example, it is known that when manufacturing a liquid crystal display element in the PSA mode, a light irradiation amount of 100,000 J / m ² is required. However, the liquid crystal display element of the present invention can use an irradiation light amount of less than 100,000 J / m ² or even less than 50,000 J / m ² To obtain a liquid crystal display element having a predetermined pretilt angle characteristic, and reduce the manufacturing cost of the liquid crystal display element. Furthermore, it is possible to suppress deterioration of electrical properties and deterioration of reactivity of liquid crystal molecules due to strong light irradiation.

Then, the polarizing plate is bonded to the outer surface of the liquid crystal cell, so that the liquid crystal display element of the present invention can be manufactured. The above polarizing plate can be exemplified by a polarizing film of polyvinyl alcohol extending alignment and absorbing iodine liquid, called "H film", and a polarizing film formed by sandwiching the above polarizing film with a cellulose acetate protective film. board.

The liquid crystal display element of the present invention can be applied to various devices, such as: watches, portable game consoles, word processors, notebook computers, navigation systems, video cameras, PDAs, digital cameras, mobile phones, smart phones, and various screens. , LCD TV, electronic signage and other display devices.

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. [ Preparation of Polymer (A) ] <Synthesis Example A1-1>

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, in a four-necked conical flask, add 0.005 moles of a2-1-1 shown in Table 1-1, 0.02 moles of a2-2-1, 0.025 moles of a2-3-2, and 80 grams of N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone, abbreviated as NMP), and stirred at room temperature until dissolved. Next, 0.05 mol of a1-1 shown in Table 1 and 20 g of NMP were added and reacted at room temperature for 2 hours. After the reaction is completed, the reaction solution is poured into 1500 ml of water to precipitate a polymer. Then, the obtained polymer was filtered, and repeatedly washed with methanol and filtered three times, put into a vacuum oven, and dried at a temperature of 60 ° C to obtain a polymer (A1-1). <Synthesis Examples A1-2 to A1-13 and Comparative Synthesis Examples A1-14 to A1-16>

Synthesis Examples A1-2 to A1-13 and Comparative Synthesis Examples A1-14 to A1-16 were prepared by the same procedures as in Synthesis Example A1-1, except that the tetracarboxylic dianhydride compound or the The types and amounts of diamine compounds are shown in Table 1-1 and Table 1-2. ＜ Synthesis example A2-1 ＞

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, in a four-necked conical flask, add 0.005 moles of a2-1-1 shown in Table 2-1, 0.02 moles of a2-2-1, 0.025 moles of a2-3-2, and 80 grams of NMP and stir at room temperature until dissolved. Next, 0.05 mol of a1-1 shown in Table 1 and 20 g of NMP were added. After 6 hours of reaction at room temperature, 97 g of NMP, 0.05 mole of acetic anhydride and 0.1 mole of pyridine were added, the temperature was raised to 120 ° C., and stirring was continued for 2 hours to carry out the imidization reaction. After the reaction is completed, the reaction solution is poured into 1500 ml of water to precipitate a polymer. Then, the obtained polymer was filtered, and repeatedly washed with methanol and filtered three times, put into a vacuum oven, and dried at a temperature of 60 ° C. to obtain a polymer (A2-1). <Synthesis Examples A2-2 to A2-13 and Comparative Synthesis Examples A2-14 to A2-16>

Synthesis Examples A2-2 to A2-13 and Comparative Synthesis Examples A2-14 to A2-16 were prepared by the same procedure as Synthesis Example A2-1, except that the tetracarboxylic dianhydride compound was changed or The types of diamine compounds and their usage amounts are shown in Table 2-1 and Table 2-2; and the usage amounts of the dehydrating agent and the catalyst for the closed-loop reaction of dehydration are changed. Table 1-1: Table 1-2: table 2-1: Table 2-2: In Table 1-1, Table 1-2, Table 2-1 and Table 2-2: [ Preparation of polysiloxane (B)] <Synthesis example B-1>

A 500 ml three-necked flask was equipped with a stirrer, a condenser, and a thermometer. Then, in a three-necked flask, 1.00 mole of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (hereinafter referred to as ECETS) and 600 g of propylene glycol monomethyl ether (hereinafter referred to as PGME), and triethylamine (hereinafter referred to as TEA) aqueous solution (20 g TEA / 200 g H ₂ O) was added within 30 minutes while stirring at room temperature. Next, the three-necked flask was immersed in an oil bath at 30 ° C. and stirred for 30 minutes, and then the oil bath was heated to 90 ° C. within 30 minutes. When the internal temperature of the solution reached 75 ° C., the mixture was continuously heated and stirred for 6 hours . After the reaction is completed, the organic layer is taken out and washed with a 0.2 wt% ammonium nitrate aqueous solution to obtain a solution of an epoxy-containing polysiloxane compound.

Next, 0.50 mole of the ethylenically unsaturated compound b-2-1 and 0.2 g of a hardening accelerator UCAT 18X (manufactured by San-Apro) were added to a solution of the epoxy group-containing polysiloxane compound. Then, the three-necked flask was immersed in an oil bath at 30 ° C. and stirred for 10 minutes, and then the oil bath was heated to 115 ° C. within 30 minutes. When the internal temperature of the solution reached 100 ° C., heating and stirring were continued for 24 hours. After the reaction is completed, the organic layer is taken out, washed with water, dried with magnesium sulfate, and the solvent is removed to obtain polysiloxane (B-1). <Synthesis Example B-2 to Synthesis Example B-8 and Comparative Synthesis Example B'-1 to Comparative Synthesis Example B'-3>

Synthesis Example B-2 to Synthesis Example B-8 and Comparative Synthesis Example B'-1 to Comparative Synthesis Example B'-3 In the same procedure as in Synthesis Example B-1, the photoreactive group-containing polysiloxane was prepared. And the difference lies in that: the type of the reactant of polysiloxane (B) and its use amount, the type of catalyst and solvent and its use amount, reaction temperature and polycondensation time (see Table 3-1, Table 3-2). Table 3-1: Table 3-2: In Table 3-1 and Table 3-2: [ Preparation of liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element ] <Example 1>

Weigh 100 parts by weight of polymer (A1-1), 1 part by weight of polysiloxane (B-1), and 500 parts by weight of N-methyl-2-pyrrolidone (referred to as C-1). The liquid crystal alignment agent of Example 1 can be formed by continuously stirring until dissolved at a temperature with a stirring device.

The liquid crystal alignment agent was evaluated for each detection item, and the results are shown in Table 4. <Examples 2 to 39 and Comparative Examples 1 to 12>

Examples 2 to 39 and Comparative Examples 1 to 12 were used to prepare the liquid crystal alignment agent in the same steps as in Example 1. The difference was that the types and amounts of polymer composition, solvent, and additives were changed as shown in the table 4-1, Table 4-2, Table 4-3 and Table 5. These liquid crystal alignment agents were evaluated for each detection item, and the results obtained are shown in Table 4-1, Table 4-2, Table 4-3, and Table 5. Table 4-1: Table 4-2: Table 4-3: table 5: In Table 4-1, Table 4-2, Table 4-3 and Table 5: [ Evaluation method ] < Imidization rate >

The fluorene imidization ratio refers to the total number of fluorene imine functional groups and the number of fluorene imine rings in the polymer, and the ratio of the number of fluorene imine rings is calculated as a percentage.

The detection method is to separately dry the polymer composition of the synthesis example under reduced pressure, and then dissolve it in an appropriate deuteration solvent (for example, deuterated dimethyl sulfene), and use tetramethyl silane as a reference substance. From the results of measuring ¹ H-Nuclear magnetic resonance ( ¹ H-NMR) at room temperature (for example, 25 ° C.), the imidization ratio (%) can be obtained from the following formula. Δ1: Peak area generated by chemical shift of NH matrix protons around 10 ppm; Δ2: Peak area of other protons; α: NH in precursor (polyamine) of polymer composition Proportion of the number of one proton of the base relative to the number of other protons. ＜ Environmental resistance ＞

Using the liquid crystal alignment agents of Examples 1 to 39 and Comparative Examples 1 to 12, the liquid crystal display elements were prepared according to the method described above, and the prepared liquid crystal display elements were respectively placed at a temperature of 65 ° C and a relative humidity of 85%. In an environment, after 120 hours, the ion density was measured using an electric measuring machine (manufactured by Toyo Co., Ltd. Model 6254). The test condition is that a triangle wave of 1.7 volts and 0.01 Hz is applied at a temperature of 60 ° C. The ion density (pC) can be measured by calculating the peak area in the range of 0 to 1 volts in the current-voltage waveform. The measurement area is 3 cm × 4 cm . The lower the ion density, the better the environmental resistance. The evaluation criteria of ion density are shown below. ◎: Ion density <20 pC ○: 20 pC ≦ ion density <40 pC △: 40 pC ≦ ion density <50 pC ╳: 50 pC ≦ ion density < adhesion >

The above-mentioned liquid crystal alignment agent was spin-coated on a glass substrate, and preheated at a temperature of 80 ° C. using a heating plate. Continue heating in a nitrogen-exchanged oven at 80 ° C for 1 hour (post-baking) to form a coating film with an average film thickness of 0.08 μm. The same steps described above were repeated to obtain two glass substrates having a coating film. Take one of the glass substrates with a coating film, apply an ODF sealant (S-WB42, manufactured by Sekisui Chemical) with a diameter of about 5 mm to the coating film, and contact the ODF sealant with the coating film of the other glass substrate. Two glass substrates are bonded together. Then, after the metal halide lamp was irradiated with light of 100,000 J / m ² (365 nm conversion), it was heated in an oven at 120 ° C. for 1 hour. Then, continue to measure the adhesion with the tensile compression tester (model: SDWS-0201-100SL) of Ida Seisakusho to evaluate the adhesion of the coating film. The evaluation criteria are as follows: ◎: Adhesion ≧ 300 gf / mm ² ○ ： 300 gf / mm ² ＞ Adhesion force ≧ 200 gf / mm ² △: 200 gf / mm ² ＞ Adhesion force ≧ 100 gf / mm ² ╳: Adhesion force <100 gf / mm ² .

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.

Claims (18)

A liquid crystal alignment agent includes: a polymer (A), which is prepared by reacting a first mixture including a tetracarboxylic dianhydride component (a1) and a diamine component (a2), and the polymer (A ) Is selected from the group consisting of a polyfluorinated acid polymer, a polyfluorinated imine polymer, a polyfluorinated block copolymer, or any combination thereof; a polysiloxane (B); and a solvent (C); The diamine component (a2) includes at least one first diamine compound (a2-1) represented by the formula (1): H ₂ N-R _a -NH ₂ Formula (1) In the formula (1), R _a is _a bivalent unit represented by formula (1-1) to formula (1-11): In formulas (1-1) to (1-11), * is a bonding point; and the polysiloxane (B) includes an epoxy-containing polysiloxane (b1) and a side chain compound (b2) ), And the epoxy-containing polysiloxane (b1) comprises a copolymer obtained by hydrolyzing and partially condensing a second mixture. The liquid crystal alignment agent according to claim 1, wherein the epoxy group-containing polysiloxane (b1) includes a group represented by formula (III-1), a group represented by formula (III-2), and a group represented by formula (III -3) at least one of the bases represented: Formula (III-1) In Formula (III-1), B is an oxygen atom or a single bond; c is an integer of 1 to 3; and d is an integer of 0 to 6; when d is 0, B is a single bond; Formula (III-2) In Formula (III-2), e is an integer of 0 to 6; Formula (III-3) In formula (III-3), D is an alkylene group of C ₂ to C ₆ ; and E is a hydrogen atom or an alkyl group of C ₁ to C ₆ . The liquid crystal alignment agent according to claim 1, wherein the second mixture includes a silane monomer (b1-1) as shown in formula (III-4): Si (R _f ) _b (OR _g ) _4-b formula (III in -4) formula (III-4), R _f is a hydrogen atom, C ₁ to C ₁₀ alkyl group, the C ₂ to C ₁₀ alkenyl group of, C ₆ to C ₁₅ aryl group, the alkyl-containing epoxy groups Or an alkoxy group containing an epoxy group, and at least one R _f is an alkyl group containing an epoxy group or an alkoxy group containing an epoxy group; when b is plural, R _{f is} each the same or different; R _g is a hydrogen atom, C ₁ to C ₆ alkyl group of, C acyl or C ₁ to C ₆ aryl group of ₆ to ₁₅ of the C; 4-b when a is plural, R _g are each the same or different; and b An integer from 1 to 3. According to the liquid crystal alignment agent of claim 1, the side chain compound (b2) contains a structure represented by formula (IV): E ^1- L ^0- L ^1- Z (IV) In formula (IV), E ¹ is C ₁ to C ₃₀ alkyl, C ₃ to C ₁₀ cycloalkyl substituted or unsubstituted by C ₁ to C ₂₀ alkyl or alkoxy, or C ₁₇ to C ₅₁ hydrocarbon group containing steroid skeleton, Part of the hydrogen atoms of the alkyl and alkoxy groups of E ¹ are substituted or unsubstituted; L ⁰ is a single bond, * -O- *, * -COO- *, or * -OCO- *; L ¹ is a single bond , C ₁ to C ₂₀ alkylene, phenylene, biphenylene, cyclohexyl, dicyclohexyl or a group represented by the following formula (IV-1) or (IV-2): Formula (IV-1) Formula (IV-2) When L ¹ is a single bond, L ⁰ is a single bond; * is a bond; and Z is a monovalent organic group that reacts with an epoxy group to form a bonding group. The liquid crystal alignment agent according to claim 1, wherein the diamine component (a2) further comprises a second diamine compound (a2-2) represented by formula (2): In formula (2), in formula (2), R ¹⁵ is selected from , , , , and The group consisting of; and R ¹⁶ is an organic group represented by formula (2-1): Formula (2-1) In formula (2-1): R ¹⁷ is hydrogen, fluorine or methyl; R ¹⁸ , R ¹⁹ and R ²⁰ each independently represent a single bond, , , , , , Or C ₁ to C ₃ alkylene; R ²¹ is selected from and A group consisting of: wherein: R ²³ and R ²⁴ each independently represent hydrogen, fluorine or methyl; R ²² is selected from hydrogen, fluorine, C ₁ to C ₁₂ alkyl, and C ₁ to C ₁₂ fluoroalkyl , A group consisting of C ₁ to C ₁₂ alkoxy, -OCH ₂ F, -OCHF ₂ and -OCF ₃ ; a represents an integer of 1 or 2; g, m and i each independently represent an integer of 0 to 4 ; Y, h, and x each independently represent an integer from 0 to 3, and y + h + x ≧ 3; and z1 and z2 each independently represent 1 or 2; when R ¹⁷ , R ¹⁸ , R ¹⁹ , R ²⁰ , When there is a plurality of R ²¹ , R ²³ or R ²⁴ , they are each the same or different. The liquid crystal alignment agent according to claim 1, wherein the diamine component (a2) further comprises a third diamine compound (a2-3) represented by formula (3): Formula (3) In Formula (3), X is an organic group containing a C ₆ to C ₃₀ aromatic ring; and n is an integer of 1 to 4. According to the liquid crystal alignment agent of claim 6, the third diamine compound (a2-3) is selected from the group consisting of formulas (3-1) to (3-5): Equation (3-1) Formula (3-2) Equation (3-3) Formula (3-4) Formula (3-5) In formulas (3-1) to (3-5), X ₁ and X ₃ independently represent a single bond, -CH _2- , -C ₂ H _4- , -C (CH ₃ ) _2- , -CF _2- , -C (CF ₃ ) _2- , -O-, -CO-, -NH-, -N (CH ₃ )-, -CONH-, -NHCO-, -CH ₂ O- _{, -OCH 2 -, - COO -} , - OCO -, - CON (CH 3) - or _{-N (CH 3) CO-; X} 2 represents a C ₁ to C straight chain alkyl group or the C ₅ to C _{5 1} N1 and n7 independently represent integers from 1 to 4; n2 and n3 independently represent integers from 0 to 4; and n2 + n3 is an integer from 1 to 4; and n4, n5, and n6 independently represent 1 to 4 An integer of 5. The liquid crystal alignment agent according to claim 1, wherein the total amount of the diamine component (a2) used is 100 moles, and the amount of the first diamine compound (a2-1) represented by the formula (1) is used. For 3 to 60 moles. The liquid crystal alignment agent according to claim 5, wherein the use of the second diamine compound (a2-2) represented by formula (2) is based on a total amount of 100 moles of the diamine component (a2). The amount is 5 to 60 moles. The liquid crystal alignment agent according to claim 6, wherein the use of the third diamine compound (a2-3) represented by the formula (3) is based on the total amount of the diamine component (a2) being 100 mol. The amount is 3 to 97 moles. The liquid crystal alignment agent according to claim 3, wherein the amount of the silane monomer (b1-1) used is 0.6 mol to 1 mol based on the total amount of the monomers in the second mixture. The liquid crystal alignment agent according to claim 4, wherein the amount of the side chain compound (b2) used is 0.05 mol to 0.5 mol based on the total amount of the monomers in the second mixture. The liquid crystal alignment agent according to claim 1, wherein based on the used amount of the polymer (A) is 100 parts by weight, the used amount of the polysiloxane (B) is 1 to 30 parts by weight, and the solvent ( C) is used in an amount of 500 to 3000 parts by weight. The liquid crystal alignment agent according to claim 1, wherein the polymer (A) is a combination of a polyamidopolymer (A1) and a polyamidopolymer (A2). The liquid crystal alignment agent according to claim 14, wherein the used amount of the polyamic acid polymer (A1) is 20 to 60 parts by weight based on the used amount of the polymer (A), and the The polyfluorene imine polymer (A2) is used in an amount of 40 to 80 parts by weight. The liquid crystal alignment agent according to claim 1, wherein the fluorenimidization rate of the polymer (A) is 30% to 80%. A liquid crystal alignment film is formed of the liquid crystal alignment agent according to any one of claims 1 to 16. A liquid crystal display element includes the liquid crystal alignment film as claimed in claim 17.