TWI460210B - Liquid crystal alignment agent and liquid crystal display element - Google Patents

Description

Liquid crystal alignment agent and liquid crystal display element

The present invention relates to a liquid crystal alignment agent and a liquid crystal display element. More specifically, it relates to a liquid crystal alignment agent capable of forming a liquid crystal alignment film which exhibits excellent heat resistance and a liquid crystal display element which does not deteriorate display quality for a long period of time.

At present, as a liquid crystal display element, a TN type liquid crystal display element having a so-called TN type (twisted nematic) liquid crystal cell is widely known, and a liquid crystal alignment film is formed on a surface of a substrate on which a transparent conductive film is provided, as a substrate for a liquid crystal display element. Two substrates are disposed opposite to each other, and a nematic liquid crystal layer having positive dielectric anisotropy is formed in the gap to form a cell of the sandwich structure, and the long axis of the liquid crystal molecules is continuously twisted from one substrate to the other substrate. degree. In addition, an STN (Super Twisted Nematic) type liquid crystal display element capable of achieving higher contrast than a TN type liquid crystal display element, an IPS (in-plane switching) type liquid crystal display element having a small viewing angle dependency, and an IPS type change have been developed. OCB (Optical Compensated Bend) type liquid crystal with excellent electrode structure to increase the aperture ratio of the display element portion to improve the brightness, FFS (Fringe Field Conversion) type liquid crystal display element, and low viewing angle dependence while high-speed response of the video picture A display element and a VA (Vertical Alignment) type liquid crystal display element or the like using a nematic liquid crystal having negative dielectric anisotropy.

As a material of the liquid crystal alignment film in these liquid crystal display elements, a resin material such as polyacrylic acid, polyamidiamine, polyamine, or polyester, particularly a liquid crystal made of polyamic acid or polyimine, is known. Orientation film, heat resistance, machine Since it is excellent in mechanical strength, affinity with liquid crystal, and the like, it is used in many liquid crystal display elements (see, for example, Patent Documents 1 to 3).

The liquid crystal display element as described above requires a longer driving than before. For example, in recent years, a liquid crystal television set is required to maintain a good display state for a long period of time (for example, 10 years or more), and in particular, it is required to maintain a high voltage holding ratio even if thermal stress is applied due to long-term display driving. Performance (hereinafter also referred to as "heat resistance").

The resin material for a liquid crystal alignment film which has been known in the past has been used for the purpose of improving heat resistance by using polyiminoimine or by using p-phenylenediamine as a monomer used in the preparation thereof. However, the use of this strategy has a limited improvement in heat resistance, and the resin material for a liquid crystal alignment film which has been known in the past has been unable to satisfy the heat resistance required in an environment in which an increasingly severe liquid crystal display element is used.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. Hei 9-197411

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2003-149648

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2003-107486

[Patent Document 4] Japanese Patent Laid-Open No. Hei 6-222366

[Patent Document 5] Japanese Patent Laid-Open No. Hei 6-281937

[Patent Document 6] Japanese Patent Laid-Open No. Hei 5-170044

The present invention has been made in view of the above circumstances, and an object thereof is to provide a method capable of forming a voltage holding ratio which does not decrease even when a thermal stress is applied for a long period of time. A liquid crystal alignment agent having a high heat-resistant liquid crystal alignment film and a liquid crystal display element which does not deteriorate even if the display quality is driven for a long period of time.

Other objects and advantages of the invention will be apparent from the description which follows.

According to the present invention, the above objects and advantages of the present invention, first, are achieved by a liquid crystal alignment agent comprising at least one polymer selected from the group consisting of polylysine and polyimine, wherein the polymer At least a part of the molecules have a structure represented by the following formula (A).

The above objects and advantages of the present invention are, in the second, achieved by a liquid crystal display element having a liquid crystal alignment film formed of the above liquid crystal alignment agent.

The liquid crystal alignment agent of the present invention can form a liquid crystal alignment film which does not decrease even if a thermal stress voltage holding ratio is applied for a long period of time.

The liquid crystal display element of the present invention having such a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention does not deteriorate in display quality even when driven for a long period of time. Therefore, the liquid crystal display element of the present invention can be effectively applied to various devices, such as a clock, a portable game machine, a word processor, a notebook computer, a car navigation system, a video camera, a PDA (personal digital assistant), Display devices for digital cameras, mobile phones, various monitors, LCD TVs, etc.

detailed description

Hereinafter, the present invention will be described in detail.

The liquid crystal alignment agent of the present invention contains a selected from the group consisting of polylysine and polyimine At least one polymer in the group, wherein at least a part of the molecules of the above polymer have the structure represented by the above formula (A). Hereinafter, in the present specification, such a polymer is referred to as a "specific polymer." In the specific polymer, the structure represented by the above formula (A) may be present in the main chain of the polymer, or may be present in the side chain of the polymer, or in both the main chain and the side chain of the polymer. presence.

The structure represented by the above formula (A) is preferably at least one selected from the group consisting of structural configurations represented by the following formulas (A-1) to (A-3).

(R ^a in the formula (A-1) is ^a halogen atom, a cyano group, an isocyano group, -OCN, -NCO, -SCN, -NCS or an azide group, and n is an integer of 0 to 3,"*" are each represented as a linkage; R ^b and R ^c in the formulae (A-2) and (A-3) are each independently a hydrogen atom, a halogen atom, a cyano group, an isocyano group, -OCN, -NCO, -SCN, -NCS or azide, "*" are each represented as a linkage).

The content ratio of the structure represented by the above formula (A) in the polymer is preferably 2.0 × 10 ^-5 mol/g or more, more preferably 1.0 × 10 ^-4 to 3.0 × 10 ^-3 mol/g, which is particularly preferable. It is 2.0 × 10 ^-4 ~ 1.0 × 10 ^-3 mol / g.

The polyamic acid having at least a part of the molecule having the structure represented by the above formula (A) can be obtained, for example, by reacting the following, that is, containing the structure represented by the above formula (A) and two carboxylic anhydrides. The tetracarboxylic dianhydride of the compound of the group is reacted with a diamine or a tetracarboxylic dianhydride is reacted with a diamine containing a compound having the structure represented by the above formula (A) and two amine groups. The polyimine having at least a part of the molecule having the structure represented by the above formula (A) can be obtained, for example, by subjecting the polylysine obtained as described above to dehydration ring closure.

The specific polymer contained in the liquid crystal alignment agent of the present invention is preferably selected from the group consisting of reacting a tetracarboxylic dianhydride with a diamine containing a compound having the structure represented by the above formula (A) and two amine groups. At least one polymer selected from the group consisting of polylysine and polyamidene obtained by dehydration of the polyamic acid.

<tetracarboxylic dianhydride>

As the tetracarboxylic dianhydride for synthesizing a preferred polyphthalic acid in the liquid crystal alignment agent of the present invention, an alicyclic tetracarboxylic dianhydride, an aliphatic tetracarboxylic dianhydride, and an aromatic tetracarboxylic acid can be cited. anhydride.

Specific examples of the alicyclic tetracarboxylic dianhydride include 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,2-dimethyl-1,2,3,4-. Cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-ring Butane tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic 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 Cyclooctane-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 5-(2,5-di-side oxygen four Hydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2:3,5:6 - dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-di-oxo-3- Furyl)-naphthalene [1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5-methyl-5-(tetrahydro-2, 5-tertiary oxy-3-furanyl)-naphthalene [1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5-ethyl- 5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene [1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b- Hexahydro-7- 5-(4-hydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione, 1,3,3a,4,5, 9b-hexahydro-7-ethyl-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione, 1, 3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1 , 3-dione, 1,3,3a,4,5,9b-hexahydro-8-ethyl-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene [1, 2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5,8-dimethyl-5-(tetrahydro-2,5-di-oxo 3-furyl)-naphthalene [1,2-c]-furan-1,3-dione, 5-(2,5-di-oxo-tetrahydrofuranyl)-3-methyl-3-cyclohexene- 1,2-dicarboxylic anhydride, bicyclo[2.2.2]-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 3-oxabicyclo[3.2.1]octane-2, 4-dione-6-spiro-3'-(tetrahydrofuran-2',5'-dione), a compound represented by the following formula (TI) and (T-II), and the like;

(In the formulae (TI) and (T-II), R ¹ and R ³ are each a divalent organic group having an aromatic ring, and each of R ² and R ⁴ is a hydrogen atom or an alkyl group, and a plurality of R ² and R ⁴ may each be the same or different).

Specific examples of the aliphatic tetracarboxylic dianhydride include butane tetracarboxylic dianhydride and the like.

Specific examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3', 4,4'-benzophenonetetracarboxylic dianhydride, and 3,3', 4, and 4 '-Diphenylphosphonium tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4 '-Diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-dimethyldiphenylnonane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylnonane IV Carboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 4,4'- Bis(3,4-dicarboxyphenoxy)diphenylphosphonium dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4, 4'-perfluoroisopropylidene diphthalic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, pair Phenylene-bis(triphenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4' -diphenyl ether dianhydride, bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride, ethylene glycol-bis(hydroper trimellitate), propylene glycol-double ( Water trimellitate), 1,4-butanediol - bis (anhydrotrimellitate Triglyceride), 1,6-hexanediol-bis(anhydrotrimellitic acid ester), 1,8-octanediol-bis(anhydrotrimellitic acid ester), 2,2-di(4- Hydroxyphenyl)propane-bis(hydrogen trimellitate), a compound represented by the following formula (T-1) to (T-4), and the like.

These tetracarboxylic dianhydrides may be used alone or in combination of two or more.

The preferred polyamic acid tetracarboxylic dianhydride for use in the synthesis of the liquid crystal alignment agent of the present invention preferably contains an alicyclic tetracarboxylic dianhydride, pyromellitic dianhydride and 2,2'. A tetracarboxylic dianhydride of at least one of the group consisting of 3,3'-biphenyltetracarboxylic dianhydride (hereinafter referred to as "specific tetracarboxylic dianhydride"). The specific tetracarboxylic dianhydride is preferably selected from the group consisting of 1,2,3,4-cyclobutane tetracarboxylic dianhydride and 1,3-dimethyl group from the viewpoint of exhibiting good liquid crystal alignment. 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2, 3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 5-(2,5-di-tertiary tetrahydro-3-furanyl)-3-methyl 3-cyclohexene-1,2-dicarboxylic anhydride, 5-(2,5-di-oxo-tetrahydrofuranyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, cis 3-,7-Dibutylcyclooctane-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2 :3,5:6-dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene [1,2 -c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-di-oxo-3-furan -Naphthalene [1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5,8-dimethyl-5-(tetrahydro- 2,5-dioxaxy-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione, bicyclo[2.2.2]-oct-7-ene-2,3,5 ,6-tetracarboxylic dianhydride, 3-oxabicyclo[3.2.1]octane-2,4-dione-6-spiro-3'-(tetrahydrofuran-2',5'-di In the compound represented by the above formula (TI), the compound represented by the following formula (T-5) to (T-7) and the compound represented by the above formula (T-II) have the following formula (T-8). At least one of the group consisting of a compound, pyromellitic dianhydride, and 2,2',3,3'-biphenyltetracarboxylic dianhydride,

More preferably, it contains a compound selected from 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2, 3,5-tricarboxycyclopentyl acetic acid dianhydride, 5-(2,5-di-oxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3 -dione, cis-3,7-dibutylcyclooctane-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 3,5,6-tricarboxy-2-carboxyl Norbornane-2:3,5:6-dianhydride, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-di-oxo-3 -furyl)-naphthalene [1,2-c]-furan-1,3-dione, 3-oxabicyclo[3.2.1]octane-2,4-dione-6-spiro-3'- (tetrahydrofuran-2',5'-dione), a compound represented by the above formula (T-5), pyromellitic dianhydride, and 2,2',3,3'-biphenyltetracarboxylic dianhydride At least one of the group of tetracarboxylic dianhydrides is particularly preferably selected from the group consisting of 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 2,3,5-tricarboxycyclopentyl acetic acid dianhydride. 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan a group consisting of -1,3-diketone and pyromellitic dianhydride At least one of the groups.

Preferred other tetracarboxylic dianhydrides which can be used in combination with a specific tetracarboxylic dianhydride include, for example, butane tetracarboxylic dianhydride and 3,3',4,4'-benzophenonetetracarboxylic acid. Anhydride, 3,3',4,4'-diphenylphosphonium tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, and the like.

The tetracarboxylic dianhydride used for synthesizing the polyamic acid in the liquid crystal alignment agent of the present invention preferably contains 60 mol% or more of the specific tetracarboxylic dianhydride as described above with respect to all of the tetracarboxylic dianhydride. It preferably contains 80 mol% or more.

<Diamine>

A preferred polyamine of a poly-proline which is used in the synthesis of the liquid crystal alignment agent of the present invention is a compound having a structure represented by the above formula (A) and two amine groups (hereinafter referred to as "compound (A)"). Diamine.

The compound (A) is preferably a compound selected from the group consisting of the structure represented by the above formula (A-1) and two amine groups (hereinafter referred to as "compound (A-1)"), and has the above formula (A-2). a compound represented by the structure and two amine groups (hereinafter referred to as "compound (A-2)") and a compound having the structure represented by the above formula (A-3) and two amine groups (hereinafter referred to as "compound ( A-3)") at least one of the group consisting of. R ^a in the above formula (A-1) is preferably a halogen atom, more preferably a fluorine atom. n is 0 or 1. R ^b and R ^c in the above formulae (A-2) and (A-3) are each preferably a hydrogen atom or a halogen atom, more preferably a hydrogen atom or a fluorine atom.

The compound (A-1) is, for example, a compound represented by the following formula (A-1-1), and the like.

(In the formula (A-1-1), R ^a and n are the same as defined in the above formula (A-1), and Y ^a is a single bond or an extended aryl group having 6 to 10 carbon atoms). Examples of the extended aryl group having 6 to 10 carbon atoms of Y ^a in the above formula (A-1-1) include a 1,4-phenylene group and a 1,5-naphthylene group. Specific examples of the compound represented by the above formula (A-1-1) include, for example, 2,6-diaminobenzothiazole, 2,7-diaminobenzothiazole, and 2-(4-aminobenzene). 6-aminobenzothiazole, 2-(4-aminophenyl)-7-aminobenzothiazole, and the like.

Examples of the compounds (A-2) and (A-3) include compounds represented by the following formulas (A-2-1) and (A-3-1), and the like.

(In the formulae (A-2-1) and (A-3-1), R ^b and R ^c are the same as defined in the above formula (A-2) or (A-3), respectively, and Y ^b and Y ^c are each Independently a single bond or an extended aryl group having 6 to 10 carbon atoms). Examples of the aryl group having 6 to 10 carbon atoms of Y ^b and Y ^c in the above formulae (A-2-1) and (A-3-1) include, for example, 1,4-phenylene group, 1,5-naphthyl and the like. Specific examples of the compound represented by the above formula (A-2-1) include, for example, 2,6-diaminobenzo[1,2-d:4,5-d']dithiazole, 2,6- Bis(4-aminophenyl)benzo[1,2-d:4,5-d']dithiazole or the like; as a specific example of the compound represented by the above formula (A-3-1), for example, 2 ,6-Diaminobenzo[1,2-d:5,4-d']dithiazole, 2,6-bis(4-aminophenyl)benzo[1,2-d:5,4 -d'] Dithiazole and the like.

As the diamine for synthesizing the preferred polyglycolic acid in the liquid crystal alignment agent of the present invention, only the compound (A) as described above may be used, or the compound (A) may be used in combination with other diamines.

Examples of the other diamine which can be used herein include an aromatic diamine, an aliphatic diamine, an alicyclic diamine, a diamine having two primary amino groups in the molecule, and a nitrogen atom other than the primary amino group. Substituted phenylenediamine, diamine-based organodecane, and the like.

Examples of the aromatic diamine include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, and 4,4. '-Diaminodiphenyl sulfide, 4,4'-diaminodiphenylanthracene, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-di Aminobenzamide, 4,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 5- Amino-1-(4'-aminophenyl)-1,3,3-trimethylindan, 6-amino-1-(4'-aminophenyl)-1,3,3- Trimethylindan, 3,4'-diaminodiphenyl ether, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diamine Dibenzophenone, 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]anthracene, 1,4-bis(4-amino Phenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 9,9-bis(4-aminophenyl) )-10-hydroquinone, 2,7-diaminopurine, 9,9-bis(4-aminophenyl)anthracene, 4,4'-methylene-bis(2-chloroaniline), 2, 2',5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-Dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 4,4'-(p-phenylene diisopropylidene)diphenylamine, 4,4'-(m-phenylene diisopropylidene)diphenylamine, 2,2'-bis[4-(4- Amino-2-trifluoromethylphenoxy)phenyl]hexafluoropropane, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 4,4'-double [(4-Amino-2-trifluoromethyl)phenoxy]-octafluorobiphenyl, bis(4-aminophenyl)benzidine, the following formula (D-1)~(D-5) Compounds represented by each, etc.

(y in the formula (D-4) is an integer of 2 to 12, and z in the formula (D-5) is an integer of 1 to 5); as the above aliphatic diamine, for example, 1,1-m-benzene Dimethylamine, 1,3-propanediamine, butanediamine, pentanediamine, hexamethylenediamine, heptanediamine, octanediamine, decanediamine, etc.; as the alicyclic diamine, for example, 4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadiene diamine, tricyclo[6.2.1.0 ^2,7 ]undecyldimethyldiamine, 4,4 '-methylenebis(cyclohexylamine), 1,3-bis(aminomethyl)cyclohexane, etc.; as a diamine having two primary amino groups in the molecule and a nitrogen atom other than the primary amine group For example, 2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 5,6-diamino-2, 3-dicyanopyridine ,5,6-diamino-2,4-dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-three 1,4-bis(3-aminopropyl)per 2,4-Diamino-6-isopropoxy-1,3,5-three 2,4-diamino-6-methoxy-1,3,5-three 2,4-diamino-6-phenyl-1,3,5-three 2,4-diamino-6-methyl-s-three 2,4-diamino-1,3,5-three 4,6-Diamino-2-vinyl-s-three , 2,4-Diamino-5-phenylthiazole, 2,6-diaminopurine, 5,6-diamino-1,3-dimethyluracil, 3,5-diamino- 1,2,4-triazole, 6,9-diamino-2-ethoxyacridine lactate, 3,8-diamino-6-phenylphenanthridine, 1,4-diamine Piper , 3,6-diaminoacridine, bis(4-aminophenyl)phenylamine, 1-(3,5-diaminophenyl)-3-indolyl succinylamine, 1-(3 , 5-diaminophenyl)-3-octadecyl succinylamine, a compound represented by the following formula (DI),

(In the formula (DI), R ⁵ is selected from the group consisting of pyridine, pyrimidine, and tri Piperidine and piperazine a monovalent organic group having a nitrogen atom-containing cyclic structure of the group, X ¹ is a divalent organic group, R ⁶ is an alkyl group having 1 to 4 carbon atoms, and a1 is an integer of 0 to 3) a compound represented by the following formula (D-II), etc.

(In the formula (D-II), R ⁷ is selected from the group consisting of pyridine, pyrimidine, and tri Piperidine and piperazine a divalent organic group having a nitrogen atom-containing cyclic structure of the group, wherein each of X ² is a divalent organic group, and a plurality of X ² groups may be the same or different, and each of R ⁸ is a carbon atom. The alkyl group of 1 to 4, each of a2 is an integer of 0 to 3), and examples of the monosubstituted phenylenediamine include a compound represented by the following formula (D-III).

(In the formula (D-III), R ⁹ is -O-, -COO-*, -OCO-*, -NHCO-*, -CONH-* (wherein, among the above, a connection key with "*") Linked to R ¹⁰ ) or -CO-, R ¹⁰ is a monovalent organic group having a skeleton or group selected from the group consisting of an anthracene skeleton, a trifluoromethylphenyl group, a trifluoromethoxyphenyl group, and a fluorophenyl group Or an alkyl group having 6 to 30 carbon atoms, R ¹¹ is an alkyl group having 1 to 4 carbon atoms, and a3 is an integer of 0 to 3); as the above-mentioned diaminoorganomethoxy alkane, for example, a compound represented by the formula (D-IV), etc.

(In the formula (D-IV), each of R ¹² is a hydrocarbon group having 1 to 12 carbon atoms, and a plurality of R ¹² groups may be the same or different, and p is an integer of 1 to 3, and q is 1 to 2; An integer of 20). These diamines may be used alone or in combination of two or more.

The benzene ring of the above aromatic diamine may be optionally substituted by one or two or more alkyl groups (preferably methyl groups) having 1 to 4 carbon atoms. R ⁶ , R ⁸ and R ^{11 in the} above formulae (DI), (D-II) and (D-III) are each preferably a methyl group, and each of a1, a2 and a3 is preferably 0 or 1, more preferably 0.

The anthracene skeleton in R ¹⁰ of the above formula (D-III) means a skeleton composed of a cyclopentane-perhydrophenanthrene nucleus or a skeleton in which one or two or more of the carbon-carbon bonds are changed to a double bond. The monovalent organic group of R ¹⁰ having such an anthracene skeleton is preferably a group having 17 to 51 carbon atoms, more preferably a group having 17 to 29 carbon atoms.

Specific examples of R ¹⁰ having such a steroid skeleton include, for example, cholestyl-3-yl, cholest-5-en-3-yl, cholest-24-en-3-yl, cholesteric- 5,24-dien-3-yl, lanostan-3-yl and the like.

Specific examples of the compound represented by the above formula (DI) include a compound represented by the following formula (D-6);

Specific examples of the compound represented by the above formula (D-II) include a compound represented by the following formula (D-7);

Specific examples of the compound represented by the above formula (D-III) include compounds represented by the following formulas (D-8) to (D-16), and the like.

As the other diamine for synthesizing the preferred polylysine in the liquid crystal alignment agent of the present invention, among the above, it is preferably selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4, 4 '-Diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,7-diaminostilbene, 4,4'-diaminodiphenyl ether, 2,2-bis[4-( 4-aminophenoxy)phenyl]propane, 9,9-bis(4-aminophenyl)anthracene, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoro Propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-(pair Phenylenediisopropylidene)diphenylamine, 4,4'-(m-phenylene diisopropylidene)diphenylamine, 1,4-cyclohexanediamine, 4,4'-methylene (cyclohexylamine), 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, the above formula (D-1)~(D -5) each represented by a compound, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, the above formula (D- 6) a compound represented by the above formula (D-7), a compound represented by the above formula (D-III), and 1,3-bis(3-diaminopropyl)-tetramethyldioxane At least one of the group formed.

As the compound represented by the above formula (D-III), it is preferred that R ^{9 in the} above formula (D-III) is -O- or -COO-* (wherein the bond having "*" is bonded to R ¹⁰ ), R ¹⁰ is a compound having a monovalent organic group of an anthracene skeleton, and particularly preferably a compound represented by each of the above formulas (D-8) to (D-13).

As the other diamine, it preferably contains a compound selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, and bis[4-(4-amine). a diamine of at least one of the group consisting of a compound represented by the above formula (D-III), particularly preferably selected from the group consisting of p-phenylenediamine and 4,4'-diamine. At least one of the group consisting of diphenylmethane, 4,4'-diaminodiphenyl ether and bis[4-(4-aminophenoxy)phenyl]anthracene and the above formula (D-III) ) a diamine of the compound represented.

The preferred polyamine of the polyglycolic acid used in the synthesis of the liquid crystal alignment agent of the present invention preferably contains 1 mol% or more, more preferably 5 to 90 mol%, and even more preferably 10% based on the entire diamine. ~80 mol%, particularly preferably contains 15-30 mol% of compound (A).

Preferred for the synthesis of the poly-proline in the liquid crystal alignment agent of the present invention The amine preferably contains 1 to 50 mol%, more preferably 5 to 30 mol% of the compound represented by the above formula (D-III), based on the entire diamine.

The preferred polyamine of the polyglycolic acid used in the synthesis of the liquid crystal alignment agent of the present invention preferably contains 30 to 90 mol%, more preferably 40 to 80 mol%, based on the entire diamine. a group of phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether and bis[4-(4-aminophenoxy)phenyl]anthracene At least one of the groups.

<Synthesis of polylysine>

The preferred polylysine in the liquid crystal alignment agent of the present invention can be obtained by reacting the tetracarboxylic dianhydride as described above with the diamine containing the compound (A).

The ratio of use of the tetracarboxylic dianhydride to the diamine supplied to the polyaminic acid synthesis reaction is preferably 0.2 to 2 equivalents based on 1 equivalent of the amine group in the diamine, and the anhydride group of the tetracarboxylic dianhydride is 0.2 to 2 equivalents. More preferably, it is a ratio of 0.7 to 1.2 equivalents.

The synthesis reaction of polylysine is preferably carried out in an organic solvent, preferably at -20 to 150 ° C, more preferably at 0 to 100 ° C, preferably for 1 to 72 hours, more preferably 3 to 48. hour. Here, the organic solvent is not particularly limited as long as it is a solvent capable of dissolving the produced polyamic acid, and examples thereof include 1-methyl-2-pyrrolidone and N,N-dimethylacetamide. N,N-dimethylformamide, 3-butoxy-N,N-dimethylpropanamide, 3-methoxy-N,N-dimethylpropanamide, 3-hexyloxy - aprotic compounds such as guanamine compounds such as N,N-dimethylpropionamide, dimethyl hydrazine, γ -butyrolactone, tetramethyl urea, hexamethylphosphonium triamine; m-methylphenol a phenolic compound such as xylenol, phenol or halogenated phenol. The amount (α) of the organic solvent is usually such that the total amount (β) of the tetracarboxylic dianhydride and the diamine is 0.1 to 30% by weight based on the total amount (α + β) of the reaction solution. Further, when the organic solvent is used in combination with the poor solvent described below, the amount (α) of the above organic solvent is understood to mean the total amount of the organic solvent and the poor solvent.

In the above organic solvent, alcohols, ketones, esters, ethers, halogenated hydrocarbons which are generally considered to be poor solvents of polyaminic acid may be used in combination in a range in which the produced polyaminic acid is not precipitated. , hydrocarbons, etc. Specific examples of such a poor solvent include methanol, ethanol, isopropanol, cyclohexanol, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol, propylene glycol, and 1,4-butane. Alcohol, triethylene glycol, ethylene glycol monomethyl ether, ethyl lactate, butyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, acetic acid Ester, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate, diethyl ether, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol n-propyl ether, B Glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diglyme, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, digan Alcohol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane Alkane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, etc. .

When the organic solvent is used in combination with the above-described poor solvent, the use ratio of the poor solvent can be appropriately set within a range in which the produced polyamine acid is not precipitated, and the total amount of the organic solvent and the poor solvent is It is preferably 30% by weight or less, more preferably 20% by weight or less.

As described above, a reaction solution in which polylysine was dissolved was obtained.

The reaction solution may be directly supplied to a liquid crystal alignment agent to be prepared, or the polyamic acid contained in the reaction solution may be separated and supplied to a liquid crystal alignment agent for preparation, or the separated polyamic acid may be purified. The liquid crystal alignment agent is then supplied for preparation.

When the poly (proline) is dehydrated and closed to form a polyimine, the reaction solution may be directly supplied to the dehydration ring-closure reaction, or the poly-proline contained in the reaction solution may be separated and supplied to the dehydration ring closure reaction, or The separated polyamic acid can be purified and then supplied to a dehydration ring closure reaction.

The separation of the polyamic acid can be carried out by adding the above reaction solution to a large amount of a poor solvent to obtain a precipitate, and then drying the precipitate under reduced pressure, or decompressing the organic solvent in the reaction solution with an evaporator. The distillation method is carried out. Further, the polylysine can be purified by dissolving the polylysine in an organic solvent, then precipitating it with a poor solvent, or performing a step of distilling off one or several times with an evaporator under reduced pressure. .

<polyimine]

The preferred polyimine in the liquid crystal alignment agent of the present invention can be obtained by dehydrating and ring-closing polylysine as described above.

The polyimine in the liquid crystal alignment agent of the present invention may be a complete ruthenium imide of a protonic acid structure in which the precursor polyamic acid has a dehydration ring closure, or a partial dehydration ring closure of only the proline structure. a partial ruthenium imide of a valeric acid structure and a quinone ring structure.

The polyamidene contained in the liquid crystal alignment agent of the present invention has a ruthenium imidization ratio It is preferably 40 mol% or more, more preferably 80 mol% or more. By using a polyimine having a ruthenium iodide ratio of 40 mol% or more, a liquid crystal alignment agent capable of forming a liquid crystal alignment film having better charge leakage property can be obtained.

The ruthenium iodide ratio is a total amount of the guanidine structure and the number of the quinone ring structure of the polyimine, and the ratio of the number of the quinone ring structure is expressed by a percentage. At this time, a part of the quinone ring may also be an isoindole ring. The ruthenium imidization rate can be determined by dissolving the polyimine in a suitable deuterated solvent (for example, deuterated dimethyl hydrazine) and using tetramethyl decane as a reference substance at room temperature (for example, 25 ° C). ¹ H-NMR was determined from the measurement results according to the following formula (1).

Ruthenium amination rate (%) = (1-A ¹ /A ² × α ) × 100 (1)

(In formula (1), A ¹ is the peak area derived from the NH proton present near the chemical shift of 10 ppm, A ² is the peak area derived from other protons, and α is the precursor relative to the polyimine (poly Proton of one NH group in the amino acid), the ratio of the number of other protons).

Dehydration ring closure of polylysine, preferably (i) by heating poly-proline, or (ii) by dissolving poly-proline in an organic solvent, adding a dehydrating agent and a dehydration ring-closing catalyst to the solution It is carried out according to the method of heating required.

The reaction temperature in the method for heating poly-proline in the above (i) is preferably 50 to 200 ° C, more preferably 60 to 170 ° C. The reaction time is preferably from 1 to 8 hours, more preferably from 3 to 5 hours. When the reaction temperature is less than 50 ° C, the dehydration ring-closure reaction may not proceed sufficiently. When the reaction temperature exceeds 200 ° C, the molecular weight of the obtained polyimine may decrease.

On the other hand, in the method of adding the dehydrating agent and the dehydration ring-closure catalyst to the polyamic acid solution of the above (ii), as the dehydrating agent, an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used. The amount of the dehydrating agent is determined according to the desired hydrazine imidization ratio, and is preferably 0.01 to 20 moles per mole of the 1 molar acid structure of the polyglycolic acid. Further, as the dehydration ring-closure catalyst, for example, a tertiary amine such as pyridine, trimethylpyridine, dimethylpyridine or triethylamine can be used. However, it is not limited to these. The amount of the dehydration ring-closing catalyst is preferably 0.01 to 10 moles relative to the dehydrating agent used for 1 mole. The more the amount of the above dehydrating agent and the dehydration ring-closing agent, the higher the yield of ruthenium. The organic solvent used for the dehydration ring-closure reaction may, for example, be an organic solvent exemplified as an organic solvent used in the synthesis of polyglycine. The reaction temperature of the dehydration ring closure reaction is preferably from 0 to 180 ° C, more preferably from 10 to 150 ° C. The reaction time is preferably from 1 to 8 hours, more preferably from 3 to 5 hours.

The polyimine obtained in the above method (i) may be directly supplied to a liquid crystal alignment agent for preparation, or may be prepared by refining the obtained polyimine and then supplying it to a liquid crystal alignment agent. Further, in the above method (ii), a reaction solution containing polyienimine is obtained. The reaction solution may be directly supplied to a liquid crystal alignment agent for preparation, or may be prepared by supplying a liquid crystal alignment agent after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, or may be separated from the polyimine and then supplied to the liquid crystal alignment agent. The preparation may be carried out, or the separated polyimine may be purified and then supplied to a liquid crystal alignment agent for preparation. The dehydrating agent and the dehydration ring-closure catalyst are removed from the reaction solution, and a method such as solvent replacement can be employed. The separation and purification of polyimine can be carried out in the same manner as described above for the separation and purification of polylysine. The operation proceeds.

- terminal modified polymer -

Each of the polyamic acid and the polyimine contained in the liquid crystal alignment agent of the present invention may be a terminal modified polymer having a molecular weight adjusted. By using the terminal-modified polymer, the coating performance and the like of the liquid crystal alignment agent can be further improved without impairing the effects of the present invention. Such a terminal-modified polymer can be carried out by adding a molecular weight modifier to a polymerization reaction system during the synthesis of poly-proline. Examples of the molecular weight modifier include a monoanhydride, a monoamine compound, and a monoisocyanate compound.

As the above monoanhydride, for example, maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl succinic anhydride, n-hexadecyl amber may be mentioned. Anhydride, etc. Examples of the above monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-decylamine, n-decylamine, n-undecylamine, and positive ten. Dialkylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecaneamine, n-octadecylamine, n-icosylamine, and the like. The monoisocyanate compound may, for example, be phenyl isocyanate or naphthyl isocyanate.

The use ratio of the molecular weight modifier is preferably 20 parts by weight or less, more preferably 10 parts by weight or less based on the total amount of the tetracarboxylic dianhydride and the diamine used in the synthesis of the polyglycolic acid.

- solution viscosity -

Polylysine and polyimine prepared as above, each preferably having a concentration of 10% by weight of a solution having a concentration of 20 to 800 mPa. s solution viscosity, More preferably with 30~500mPa. s solution viscosity.

The solution viscosity (mPa.s) of the above polymer is a value measured at 25 ° C using an E-type rotational viscometer at a concentration of 10% by weight of a polymer solution prepared using a good solvent of the polymer.

<Other additives>

The liquid crystal alignment agent of the present invention contains a specific polymer as described above as an essential component, and may further contain other components as needed. Examples of such other components include other polymers, adhesion enhancers, and the like.

The above other polymers can be used for the purpose of improving solution properties and electrical properties. The other polymer is a polymer other than the specific polymer, and for example, a polyglycine prepared by reacting a tetracarboxylic dianhydride with a diamine containing no compound (A) (hereinafter referred to as "other poly" "Proline" "), a polyimine (hereinafter referred to as "other polyimine") obtained by dehydration of the poly-proline, a polyphthalamide, a polyester, a polyamide, a polypeptone Oxylkane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-phenylmaleimide) derivative, poly(meth)acrylate, and the like. Among them, other polyamines or other polyimines are preferred.

The use ratio of the other polymer is preferably 90% by weight or less, and more preferably 85% by weight or less based on the total amount of the polymer (refer to the total amount of the specific polymer and the other polymer, the same applies hereinafter).

The above-mentioned adhesiveness enhancer can be used for the purpose of improving the adhesion of the formed liquid crystal alignment film to the surface of the substrate. Examples of such a binder enhancer include a compound having at least one epoxy group in the molecule (hereinafter referred to as "epoxy compound"), a functional decane compound, and the like.

Examples of the epoxy group compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and neopentyl Alcohol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl ether, N, N, N', N'-four Glycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-4, 4'-Diaminodiphenylmethane, 3-(N-allyl-N-glycidyl)aminopropyltrimethoxydecane, 3-(N,N-diglycidyl)aminopropyl Trimethoxy decane and the like.

The use ratio of the epoxy group as described above is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight, based on 100 parts by total of the total amount of the polymer.

The functional decane compound may, for example, be 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane or 2-aminopropyl. Triethoxy decane, N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxy Baseline, 3-ureidopropyltrimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-ethoxycarbonyl-3 -Aminopropyltriethoxydecane, N-triethoxydecylpropyltriethylenetriamine, N-trimethoxydecylpropyltriethylenetriamine, 10-trimethoxydecane-1 ,4,7-triazadecane, 10-triethoxydecyl-1,4,7-triazadecane, 9-trimethoxydecyl-3,6-diazaindole Acid ester, 9-triethoxydecyl-3,6-diazadecyl acetate, N-benzyl-3-aminopropyltrimethoxydecane, N-benzyl-3-amino Propyl triethoxy Baseline, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltriethoxydecane, N-bis(oxyvinyl)-3-aminopropyl Trimethoxy decane, N-bis(oxyvinyl)-3-aminopropyltriethoxydecane, and the like.

The use ratio of the functional decane compound as described above is preferably 2 parts by weight or less, more preferably 0.01 to 0.2 parts by weight, per 100 parts by weight of the total amount of the polymer.

The liquid crystal alignment agent of the present invention is preferably prepared by dissolving a specific polymer as described above and other additives optionally blended as needed in an organic solvent.

Examples of the organic solvent which can be used in the liquid crystal alignment agent of the present invention include N-methyl-2-pyrrolidone, γ -butyrolactone, γ -butyrolactam, N,N-dimethylformamide, and N. , N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethoxylate Ethyl propionate, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene Alcohol ether acetate, diglyme, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate , 3-butoxy-N,N-dimethylpropanamide, 3-methoxy-N,N-dimethylpropanamide, 3-hexyloxy-N,N-dimethylpropionamidine Amines, etc.

The solid content concentration in the liquid crystal alignment agent of the present invention (the ratio of the total weight of the components other than the solvent in the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, etc., preferably 1 to 10 parts by weight. The range of %. That is, the liquid crystal alignment agent of the present invention is coated as follows On the surface of the substrate, a coating film as a liquid crystal alignment film is preferably formed by heating. When the solid content concentration is less than 1% by weight, the thickness of the coating film is too small to obtain a good liquid crystal alignment film; on the other hand, when solid When the content concentration exceeds 10% by weight, the thickness of the coating film is too thick to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal alignment agent increases, resulting in deterioration of coating properties.

The particularly preferable solid content concentration range differs depending on the method used to apply the liquid crystal alignment agent to the substrate. For example, when the spin coating method is employed, the particularly preferable solid content concentration is in the range of 1.5 to 4.5% by weight. When using the printing method, the solid content concentration is in the range of 3 to 9 wt%, so that the solution viscosity can be reduced to 12 to 50 mPa. The scope of s. When using the inkjet method, it is particularly preferable to make the solid content concentration in the range of 1 to 5% by weight, so that the solution viscosity can be reduced to 3 to 15 mPa. The scope of s.

The temperature at which the liquid crystal alignment agent of the present invention is prepared is preferably 0 ° C to 200 ° C, more preferably 20 ° C to 60 ° C.

The liquid crystal display element of the present invention has a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention as described above.

As a preferable operation mode of the liquid crystal display element of the present invention, a TN type, a VA type, and an IPS type can be cited.

The liquid crystal display element of the present invention can be produced, for example, by the following steps (1) to (3). For step (1), the substrates used differ depending on the desired mode of operation. Steps (2) and (3) are common to various modes of operation.

(1) First, a coating film is formed on a substrate by applying the liquid crystal alignment agent of the present invention on a substrate and then heating the coated surface.

(1-1) When manufacturing a TN type or VA type liquid crystal display element, two substrates each having a patterned transparent conductive film are used as a pair, preferably by offset printing, roll coating, spin coating or spraying In the ink printing method, the liquid crystal alignment agent of the present invention is applied to each of the surfaces on which the transparent conductive film is formed to form a coating film. Here, as the substrate, for example, glass such as float glass or soda lime glass; polyethylene terephthalate, polybutylene terephthalate, polyether oxime, polycarbonate, poly (aliphatic ring) can be used. Plastic transparent substrate such as olefin). As the transparent conductive film provided on one surface of the substrate, a NESA film made of tin oxide (SnO ₂ ) (registered trademark of PPG, USA), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), or the like can be used. The pattern-forming transparent conductive film can be obtained, for example, a method of forming a pattern by photolithography after forming a transparent conductive film without a pattern, a method of using a mask having a desired pattern when a transparent conductive film is formed, or the like. In the application of the liquid crystal alignment agent, in order to further improve the adhesion between the surface of the substrate and the transparent conductive film and the coating film, a functional decane compound or a functional titanium may be preliminarily coated on the surface of the substrate on which the coating film is to be formed. Pretreatment of compounds and the like.

After the liquid crystal alignment agent is applied onto such a substrate, preheating (prebaking) is preferably performed for the purpose of preventing liquid sagging or the like. The prebaking temperature is preferably from 30 to 200 ° C, more preferably from 40 to 150 ° C, and particularly preferably from 40 to 100 ° C. The prebaking time is preferably from 0.25 to 10 minutes, more preferably from 0.5 to 5 minutes. After the prebaking, in order to completely remove the solvent in the film and when the polymer contained in the liquid crystal alignment agent has a proline structure, it is subjected to a retanning (post-baking) step for the purpose of thermally imidating it. The post-baking temperature is preferably from 80 to 300 ° C, more preferably from 120 to 250 ° C. The post-baking time is preferably 5 to 200 minutes. More preferably 10 to 100 minutes.

The thickness of the coating film thus formed is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

(1-2) On the other hand, when manufacturing an IPS type liquid crystal display element, it is preferable to employ an offset printing method, a roll coating method, a spin coating method, or an inkjet printing method, and a transparent conductive film having a comb-tooth pattern is provided. The liquid crystal alignment agent of the present invention is applied to the conductive film formation surface of the substrate and the surface of the opposite substrate on which the conductive film is not provided, and then each of the coated surfaces (prebaking and post-baking) is preferably heated to form a coating film.

At this time, the material of the substrate and the transparent conductive film to be used, the method of forming the transparent conductive film pattern, the pre-treatment of the substrate, the pre-baking and post-baking conditions after coating, the film thickness of the formed coating film, and the above ( 1-1) Same.

In any of the above (1-1) and (1-2), the liquid crystal alignment agent of the present invention forms a coating film as a liquid crystal alignment film by removing an organic solvent after coating, when the liquid crystal alignment agent of the present invention contains When the polymer is a poly-proline or a polyimine having a quinone ring structure and a proline structure, it can also be subjected to a dehydration ring-closure reaction by further heating after forming a coating film to form a further quinone imine. Coating film.

(2) The coating film formed as described above may be used as a liquid crystal alignment film for a VA liquid crystal display element as it is, or the coating film surface may be optionally subjected to the following polishing treatment.

When the coating film formed as described above is used as a liquid crystal alignment film for a TN type or IPS type liquid crystal display element, the coating film surface is subjected to a rubbing treatment to coat the coating film. A liquid crystal alignment film is produced by generating alignment energy of liquid crystal molecules on the film.

The sanding treatment can be carried out by rubbing the coating film surface in a certain direction by a roll wrapped with a cloth made of a fiber such as nylon, rayon, or cotton.

In the liquid crystal alignment film, the liquid crystal alignment film is formed in the above-described liquid crystal alignment film, which is disclosed in Japanese Laid-Open Patent Publication No. Hei 6-222366, or Japanese Patent Publication No. Hei 6-281937. When a part of the surface of the liquid crystal alignment film is formed on the surface of the liquid crystal alignment film, a part of the surface of the liquid crystal alignment film is formed by the irradiation of the ultraviolet ray, and the pre-tilt angle is changed in a part of the liquid crystal alignment film, as described in Japanese Laid-Open Patent Publication No. Hei 5-105044. The treatment for removing the resist film after the rubbing treatment is performed in a direction different from the previous rubbing treatment, so that each region of the liquid crystal alignment film has a different liquid crystal alignment energy, and the field of view performance of the obtained liquid crystal display element can be improved.

(3) A pair of substrates on which the liquid crystal alignment film is formed as described above is fabricated, and the two substrates are opposed to each other through a gap (cell gap) such that the rubbing directions of the liquid crystal alignment films are perpendicular or antiparallel to each other. The peripheral portions of the two substrates are bonded together with a sealant, and liquid crystal is injected into the interstitial space surrounded by the surface of the substrate and the sealant, and the injection holes are closed to constitute a liquid crystal cell. Then, a polarizing plate is bonded to the outer surface of the liquid crystal cell so that the polarizing direction thereof coincides with or perpendicular to the rubbing direction of the liquid crystal alignment film formed on each of the substrates, whereby a liquid crystal display element can be obtained. Here, as the sealant, for example, an epoxy resin containing an alumina ball as a curing agent and a separator, or the like can be used. Examples of the liquid crystal include nematic liquid crystal and dish-shaped liquid crystal. Among them, a nematic liquid crystal is preferable, and for example, a Schiff base liquid crystal, an azo azo liquid crystal, a biphenyl liquid crystal, or a phenylcyclohexane can be used. Liquid crystal, ester liquid crystal, terphenyl liquid crystal, biphenyl cyclohexane liquid crystal, pyrimidine Liquid crystal, dioxane liquid crystal, bicyclooctane liquid crystal, cubic liquid crystal, and the like. Further, in these liquid crystals, a cholesteric liquid crystal such as cholesteryl cholesteryl, cholesteryl phthalate or cholesteryl carbonate may be added under the trade names "C-15" and "CB-15" (manufactured by Merck). A chiral agent for sale, a ferroelectric liquid crystal such as a nonyloxybenzylidene-p-amino-2-methylbutyl cinnamate, or the like is used.

The polarizer to be bonded to the outer surface of the liquid crystal may be a polarizer formed by sandwiching a polarizing film called "H film" obtained by stretching a polyvinyl alcohol and simultaneously absorbing iodine, in a protective film of acetate, or H. A polarizer made of the film itself.

The liquid crystal display element of the present invention produced as described above has an advantage that the display performance does not deteriorate even if it is continuously driven for a long period of time as compared with the conventionally known liquid crystal display element. Specifically, for example, liquid crystal alignment does not occur. The film thermal deterioration causes backlight leakage or the like which causes a poor alignment of the liquid crystal.

[Examples]

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

Further, the solution viscosity of the polymer in the synthesis example was a value measured at 25 ° C using an E-type viscometer.

<Synthesis of Compound (A)> Synthesis Example 1 (Synthesis of 2,6-Diaminobenzothiazole)

The synthetic raw material 2-amino-6-nitrobenzothiazole was directly used as a product of Tokyo Chemical Industry Co., Ltd. 97.6 g (0.50 mol) of 2-amino-6-nitrobenzothiazole was dissolved in 3000 ml of ethanol, and 5 wt% of palladium/carbon 90 g was added in nitrogen. Stir at 70 ° C for 1 hour under the environment. Then, 153 ml of hydrazine monohydrate was added, and the mixture was stirred under reflux for 6 hours under a nitrogen stream to carry out a reaction. After completion of the reaction, palladium on carbon was removed by filtration through Celite, and the solvent was removed from the filtrate. The obtained solid was sufficiently washed with distilled water and dried to obtain 44.8 g (54.0%) of the desired compound 2,6-diaminobenzothiazole.

This synthesis operation was repeated in accordance with the above synthetic scheme to ensure the amount of 2,6-diaminobenzothiazole necessary for the synthesis of the following polymer.

<Synthesis of specific polymers> Synthesis Example 2 (Synthesis of Polyimine 1)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5 -(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione 160g (0.50 mol), p-phenylene as diamine Amine 84g (0.78 moles), 2,6-diaminobenzothiazole 16.5g (0.1 mole), 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl 32g (0.10 Mohr) and 3,6-bis(4-aminobenzylideneoxy)cholestane 6.4 g (0.010 mol), and 2.8 g (0.03 mol) of aniline as a monoamine are dissolved in 1200 g of N-A In the base-2-pyrrolidone (NMP), the reaction was carried out at 60 ° C for 9 hours to obtain a polyglycine-containing solution. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the viscosity of the solution was determined to be 58 mPa. s.

Then, 2400 g of NMP was added to the polylysine solution prepared above, and 400 g of pyridine and 410 g of acetic anhydride were further added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system is replaced with a new γ-butyrolactone solvent (by the solvent replacement operation, The pyridine and acetic anhydride used in the dehydration ring closure reaction were removed to the outside of the system. The same applies hereinafter, and then concentrated to obtain about 3700 g of a solution containing 10% by weight of polyimine (PI-1) having a ruthenium iodide ratio of about 95%. The solution viscosity of the polyimine solution is 69 mPa. s.

Synthesis Example 3 (Synthesis of Polyimine 2)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5 -(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione 160g (0.50 mol), p-phenylene as diamine Amine 94g (0.87 moles), 2,6-diaminobenzothiazole 16.5g (0.1 mole), 1,3-bis(3-aminopropyl)tetramethyldioxane 25g (0.10 Mo Ear) and 9.6 g (0.015 mol) of 3,6-bis(4-aminobenzylideneoxy)cholane, and 2.8 g (0.030 mol) of aniline as a monoamine dissolved in 960 g of NMP. The reaction was carried out for 6 hours at 60 ° C to obtain a polyglycine-containing solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the viscosity of the solution is determined to be 60 mPa. s.

Then, 2700 g of NMP was added to the obtained polyamic acid solution, and 400 g of pyridine and 410 g of acetic anhydride were further added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 3800 g of polyimine (PI-containing 10% by weight of ruthenium iodide ratio of about 88%). 2) solution. The solution viscosity of the polyimine solution is 55 mPa. s.

Synthesis Example 4 (Synthesis of Polyimine 3)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene [1 , 2-c]-furan-1,3-dione 160g (0.50 mol), p-phenylenediamine as diamine 94g (0.87 mol), 2,6-diaminobenzothiazole 16.5 g (0.1 Mohr), 1,3-bis(3-aminopropyl)tetramethyldioxane 25g (0.10 mole) and 4-(4'-trifluoromethoxybenzylideneoxy)cyclohexyl -3,5-diaminobenzoic acid ester 35g (0.080 mol), and 2.8 g (0.030 mol) of aniline as a monoamine were dissolved in 1271 g of NMP, and reacted at 60 ° C for 6 hours to obtain a polycondensation. A solution of proline. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the viscosity of the solution is determined to be 60 mPa. s.

Then, 2500 g of NMP was added to the obtained polyamic acid solution, and 400 g of pyridine and 410 g of acetic anhydride were further added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 3800 g of a polyimine (PI-containing 10% by weight of a ruthenium iodide ratio of about 96%). 3) solution. The solution viscosity of the polyimine solution is 55 mPa. s.

Synthesis Example 5 (Synthesis of Polyimine 4)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol), p-phenylenediamine as diamine 43 g (0.40 mol), 2,6-diamine Benzothiazole 16.5 g (0.1 mol) and 3-(3,5-diaminobenzylideneoxy) cholestane 52 g (0.10 mol) were dissolved in 830 g of NMP and allowed to stand at 60 ° C for 6 hours. The reaction was carried out to obtain a solution containing poly-proline. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 20% by weight, and the viscosity of the solution is determined to be 2200 mPa. s.

Then, 1500 g of NMP was added to the obtained polyamic acid solution, and 40 g of pyridine and 51 g of acetic anhydride were further added thereto, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system is replaced with a new NMP solvent, and then concentrated to obtain about 2700 g of a solution containing 7 wt% of a polyamidimide (PI-4) having a ruthenium iodide ratio of about 50%. . The solution viscosity of the polyimine solution is 30 mPa. s.

Synthesis Example 6 (Synthesis of Polyimine 5)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride 110 g (0.50 mol) as tetracarboxylic dianhydride, p-phenylenediamine 49 g (0.45 mol), 2,6-diamine as diamine Benzothiazole 16.5 g (0.1 mol) and 3-(3,5-diaminobenzylideneoxy) cholestane 26 g (0.05 mol) were dissolved in 750 g of NMP and allowed to stand at 60 ° C for 6 hours. The reaction was carried out to obtain a solution containing poly-proline. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 20% by weight, and the viscosity of the solution is determined to be 2200 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 40 g of pyridine and 51 g of acetic anhydride were further added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, a solvent of the system was replaced with a new NMP to obtain about 2500 g of a solution containing 7 wt% of a polyamidimide (PI-5) having a ruthenium iodide ratio of about 50%. The solution viscosity of the polyimine solution is 50 mPa. s.

Synthesis Example 7 (Synthesis of Polyimine 6)

110 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, p-phenylenediamine as a diamine 38 g (0.35 mol), 2,6-diamine Benzothiazole 16.5g (0.1m), 4,4'-diaminodiphenylmethane 20 g (0.1 mol) and 3-(3,5-diaminobenzylideneoxy)cholestane 26 g (0.05 mol) were dissolved in 810 g of NMP, and reacted at 60 ° C for 6 hours to obtain a polycondensation. A solution of proline. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a concentration of polyglycine of 7% by weight, and the viscosity of the solution is determined to be 65 mPa. s.

Then, 1900 g of NMP was added to the obtained polyaminic acid solution, and 80 g of pyridine and 100 g of acetic anhydride were further added thereto, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new NMP solvent to obtain about 1400 g of a solution containing 15% by weight of polyimine (PI-6) having a ruthenium iodide ratio of about 80%. Take a small amount of the polyimine solution, add NMP, and prepare a solution with a concentration of 10% by weight of polyimine, and the viscosity of the solution is determined to be 90 mPa. s.

Synthesis Example 8 (Synthesis of Polyimine 7)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride 110 g (0.50 mol) as tetracarboxylic dianhydride, p-phenylenediamine 43 g (0.40 mol) and 2,6-diamine as diamine The benzothiazole 16.5 g (0.1 mol) was dissolved in 1800 g of NMP, and reacted at 60 ° C for 6 hours to obtain a polyglycine-containing solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the viscosity of the solution is determined to be 70 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 80 g of pyridine and 100 g of acetic anhydride were further added thereto, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 1200 g of a polyimine (15-containing 15% by weight of ruthenium iodide). 7) solution. Take less The polyimine solution was added, and γ-butyrolactone was added to prepare a solution having a polyamidene concentration of 10% by weight, and the measured solution viscosity was 150 mPa. s.

Synthesis Example 9 (Synthesis of Polyimine 8)

165 g (0.75 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a,4,5,9b-hexahydro-8-methyl-5 -(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene [1,2-c]-furan-1,3-dione 78 g (0.25 mol), p-phenylene as diamine Amine 32g (0,30 moles), 2,6-diaminobenzothiazole 16.5g (0.1 mole), 4,4'-diaminodiphenyl ether 80g (0.4 moles) and two {4 -(4-Aminophenoxy)phenyl}hydrazine 85 g (0.20 mol) was dissolved in 2600 g of NMP, and reacted at 60 ° C for 6 hours to obtain a polyglycine-containing solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the measured solution viscosity is 400 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 395 g of pyridine and 310 g of acetic anhydride were further added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system is replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 1350 g of a polyimine (15-containing 15% by weight of ruthenium iodide). 8) solution. Take a small amount of the polyimine solution, add γ-butyrolactone, and prepare a solution with a concentration of 10% by weight of polyimine, and the viscosity of the solution is determined to be 90 mPa. s.

Synthesis Example 10 (Synthesis of Polyimine 9)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol), as a diamine 2,6-diaminobenzothiazole 82.5 g (0.5 mol) Dissolved in 1800g NMP and carried out at 60 ° C for 6 hours The reaction was carried out to obtain a solution containing poly-proline. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the viscosity of the solution was determined to be 65 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 80 g of pyridine and 100 g of acetic anhydride were further added thereto, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 1100 g of a polyimine (PI-containing 15% by weight of ruthenium iodide ratio of about 83%). 9) solution. Take a small amount of the polyimine solution, add γ-butyrolactone, and prepare a solution with a concentration of 10% by weight of polyimine, and the viscosity of the solution is 70mPa. s.

Synthesis Example 11 (Synthesis of Polyimine 10)

110 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, p-phenylenediamine 32 g (0.30 mol), 2,6-diamine as diamine Benzothiazole 16.5 g (0.1 mol), 2,2'-bis(trifluoromethyl)benzene 16 g (0.050 mol) and 4,4'-diaminodiphenylmethane 11 g (0.050 mol) Dissolved in 2000 g of NMP and reacted at 60 ° C for 6 hours to obtain a polyglycine-containing solution. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the viscosity of the solution was determined to be 480 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 126 g of pyridine and 163 g of acetic anhydride were further added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 1300 g of a polyamidene (PI-) containing 15% by weight of a ruthenium iodide ratio of about 88%. 10) solution. take A small amount of the polyimine solution was added with γ-butyrolactone to form a solution having a concentration of 10% by weight of polyimine, and the viscosity of the solution was determined to be 35 mPa. s.

<Synthesis of other polymers> Synthesis Example 12 (Synthesis of Other Polylysine 1)

110 g (0.50 mol) of pyromellitic dianhydride as tetracarboxylic dianhydride and 98 g (0.50 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as 4 of diamine. 4-diaminodiphenyl ether 200 g (1.0 mol) was dissolved in a mixed solvent consisting of 230 g of NMP and 2010 g of γ-butyrolactone, and after reacting at 40 ° C for 3 hours, 1350 g of γ-butyrolactone was added. A solution of about 3500 g of 10% by weight poly-proline (PA-1) was obtained. The solution viscosity of the polyaminic acid solution is 200 mPa. s.

Synthesis Example 13 (Synthesis of Other Polylysine 2)

98 g (0.50 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 110 g (0.50 mol) of pyromellitic dianhydride as 4 of diamine. 4'-Diaminodiphenylmethane 200g (1.0 mol) was dissolved in a mixed solvent consisting of 230 g of NMP and 2100 g of γ-butyrolactone, and after reacting at 40 ° C for 3 hours, 1350 g of γ-butane was added. The ester gave about 3500 g of a solution containing 10% by weight of polyglycine (PA-2). The solution viscosity of the polyaminic acid solution is 125 mPa. s.

Synthesis Example 14 (Synthesis of Other Polylysine 3)

200 g (1.0 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride as 2,2'-dimethyl-4,4'-di of diamine Aminobiphenyl 210 g (1.0 mol) was dissolved in a mixed solvent composed of 370 g of NMP and 3300 g of γ-butyrolactone, and reacted at 40 ° C for 3 hours to obtain about 3500 g of a There is a solution of 10% by weight polyglycolic acid (PA-3). The solution viscosity of the polyaminic acid solution is 160 mPa. s.

Synthesis Example 15 (Synthesis of other polylysine 4)

196 g (0.9 mol) of pyromellitic dianhydride as tetracarboxylic dianhydride and 19.6 g (0.1 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as a diamine pair 21.6 g (0.20 mol) of phenylenediamine and 180 g (0.8 mol) of 4,4'-diaminodiphenyl ether were dissolved in 2400 g of NMP, and reacted at 60 ° C for 4 hours to obtain about 2400 g containing 10 weight. A solution of % polyaminic acid (PA-4). The solution viscosity of the polyaminic acid solution is 200 mPa. s.

Synthesis Example 16 (Synthesis of Other Polyimine 1)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5 -(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione 160g (0.50 mol), p-phenylene as diamine Amine 95g (0.88 moles), 2,2-bis(trifluoromethyl)-4,4-diaminobiphenyl 32g (0.10 moles) and 3,6-bis(4-aminobenzonitrile) 6.4 g (0.010 mol) of choline, and 2.8 g (0.03 mol) of aniline as a monoamine were dissolved in 1200 g of NMP, and reacted at 60 ° C for 9 hours to obtain a polyglycine-containing solution. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the viscosity of the solution was determined to be 58 mPa. s.

Then, 2400 g of NMP was added to the obtained polyaminic acid solution, and 400 g of pyridine and 410 g of acetic anhydride were further added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system is replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 3700 g containing 10 A solution of polyamidolimine (PI-11) having a weight % oxime imidization rate of about 95%. The solution viscosity of the polyimine solution is 69 mPa. s.

Synthesis Example 17 (Synthesis of Other Polyimine 2)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5 -(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione 160g (0.50 mol), p-phenylene as diamine Amine 94g (0.87 moles), 1,3-bis(3-aminopropyl)tetramethyldioxane 25g (0.10 moles) and 3,6-bis(4-aminobenzylideneoxy) Cholesterane 9.6 g (0.015 mol), and octadecylamine 8.1 g (0.030 mol) as a monoamine were dissolved in 960 g of NMP, and reacted at 60 ° C for 6 hours to obtain polyglycine. The solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the viscosity of the solution is determined to be 60 mPa. s.

Then, 2700 g of NMP was added to the obtained polyamic acid solution, and 400 g of pyridine and 410 g of acetic anhydride were further added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone to obtain about 2300 g of polyimine (PI-12) containing 15% by weight of a ruthenium iodide ratio of about 95%. Solution. Take a small amount of the polyimine solution, add γ-butyrolactone, and prepare a solution with a concentration of 10% by weight of polyimine, and the viscosity of the solution is 70mPa. s.

Synthesis Example 18 (Synthesis of Other Polyimine 3)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 110 g (0.50 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5 -(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene[1,2-c]-furan-1,3-dione 160g (0.50 Mo Ear), p-phenylenediamine as a diamine 88g (0.82 mol), 1,3-bis(3-aminopropyl)tetramethyldioxane 25g (0.10 mol) and 4-(4' -trifluoromethoxybenzylideneoxy)cyclohexyl-3,5-diaminobenzoic acid ester 35g (0.080 mol), and 2.8 g (0.030 mol) of aniline as a monoamine dissolved in 1200 g of NMP The reaction was carried out at 60 ° C for 6 hours to obtain a polyglycine-containing solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the viscosity of the solution is determined to be 60 mPa. s.

Then, 2500 g of NMP was added to the obtained polyaminic acid solution, and 400 g of pyridine and 410 g of acetic anhydride were further added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 3600 g of a polyimine (PI-containing 10% by weight of a ruthenium iodide ratio of about 96%). 13) solution. The solution viscosity of the polyimine solution is 55 mPa. s.

Synthesis Example 19 (Synthesis of Other Polyimine 4)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride 110 g (0.50 mol) as tetracarboxylic dianhydride, p-phenylenediamine 43 g (0.40 mol) and 3-(3,5) as diamine -Diaminobenzylideneoxy)cholesterane 52 g (0.10 mol) was dissolved in 830 g of NMP, and reacted at 60 ° C for 6 hours to obtain a polyglycine-containing solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the viscosity of the solution is determined to be 60 mPa. s.

Then, 1900 g of NMP was added to the obtained polyamic acid solution, and 40 g of pyridine and 51 g of acetic anhydride were further added thereto, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system is replaced with a new NMP solvent to obtain about 1100 g containing 15% by weight of ruthenium amide. A solution of 50% polyimine (PI-14). A small amount of the polyimine solution was added, NMP was added, and a solution having a concentration of 10% by weight of polyimine was prepared, and the viscosity of the solution was determined to be 47 mPa. s.

Synthesis Example 20 (Synthesis of Other Polyimine 5)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride 110 g (0.50 mol) as tetracarboxylic dianhydride, p-phenylenediamine 49 g (0.45 mol) and 3-(3,5) as diamine -Diaminobenzimidyloxy)cholestane 26 g (0.05 mol) was dissolved in 750 g of NMP, and reacted at 60 ° C for 6 hours to obtain a polyglycine-containing solution. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the viscosity of the solution was determined to be 58 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 40 g of pyridine and 51 g of acetic anhydride were further added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new NMP solvent to obtain about 1000 g of a solution containing 15% by weight of polyimine (PI-15) having a ruthenium iodide ratio of about 50%. Take a small amount of the polyimine solution, add NMP, and prepare a solution with a concentration of 10% by weight of polyimine, and the viscosity of the solution is determined to be 85 mPa. s.

Synthesis Example 21 (Synthesis of Other Polyimine 6)

110 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 38 g (0.35 mol), 4,4'-di of p-phenylenediamine as diamine Aminodiphenylmethane 20g (0.1 mole) and 3-(3,5-diaminobenzylideneoxy)cholestane 26g (0.05 mole) were dissolved in 800g of NMP and carried out at 60 ° C The reaction was carried out in an hour to obtain a solution containing poly-proline. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a polyglycine concentration of 10% by weight. Liquid, the measured solution viscosity is 60mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 80 g of pyridine and 100 g of acetic anhydride were further added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, a solvent of the system was replaced with a new NMP to obtain about 1050 g of a solution containing 15% by weight of polyimine (PI-16) having a ruthenium iodide ratio of about 80%. Take a small amount of the polyimine solution, add NMP, and prepare a solution with a concentration of 10% by weight of polyimine, and the viscosity of the solution is determined to be 87 mPa. s.

Synthesis Example 22 (Synthesis of Other Polyimine 7)

110 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, and 54 g (0.50 mol) of p-phenylenediamine as diamine were dissolved in 1800 g of NMP. The reaction was carried out for 6 hours at 60 ° C to obtain a polyglycine-containing solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a concentration of polyglycine of 10% by weight, and the viscosity of the solution is determined to be 75 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 80 g of pyridine and 100 g of acetic anhydride were further added, and a dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 1400 g of a polyimine (PI-containing 15% by weight of ruthenium iodide ratio of about 91%). 17) solution. Take a small amount of the polyimine solution, add γ-butyrolactone, and prepare a solution with a concentration of 10% by weight of polyimine. The viscosity of the solution is 150mPa. s.

Synthesis Example 23 (Synthesis of Other Polyimine 8)

2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride 165 g (0.75 mol) and 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene [1 , 2-c]-furan-1,3-dione 78g (0.25 mol), p-phenylenediamine as diamine 43 g (0.40 mol), 4,4'-diaminodiphenyl ether 80 g ( 0.4 mol) and bis{4-(4-aminophenoxy)phenyl}hydrazine 85 g (0.20 mol) were dissolved in 2600 g of NMP, and reacted at 60 ° C for 6 hours to obtain poly-proline-containing Solution. Take a small amount of the obtained polyaminic acid solution, add NMP, and prepare a solution with a polyglycine concentration of 10% by weight, and the viscosity of the solution is determined to be 100 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and 80 g of pyridine and 100 g of acetic anhydride were further added, and the dehydration ring-closure reaction was carried out at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 2700 g of a polyimine (PI-containing 15% by weight of a ruthenium iodide ratio of about 81%). 18) solution. A small amount of the polyimine solution was added, and γ-butyrolactone was added to prepare a solution having a concentration of 10% by weight of polyimine, and the viscosity of the solution was determined to be 95 mPa. s.

Synthesis Example 24 (Synthesis of Other Polyimine 9)

110 g (0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, p-phenylenediamine as a diamine 43 g (0.40 mol), 2,2'-double 16 g (0.050 mol) of (trifluoromethyl)benzene and 11 g (0.050 mol) of 4,4'-diaminodiphenylmethane were dissolved in 2600 g of NMP, and reacted at 60 ° C for 6 hours to obtain a polycondensation. A solution of proline. A small amount of the obtained polyaminic acid solution was added, and NMP was added to prepare a solution having a polyglycine concentration of 10% by weight, and the viscosity of the solution was determined to be 480 mPa. s.

Then, 1800 g of NMP was added to the obtained polyamic acid solution, and then added. 80 g of pyridine and 100 g of acetic anhydride were subjected to a dehydration ring-closure reaction at 110 ° C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a new γ-butyrolactone solvent, and then concentrated to obtain about 2500 g of a polyimine (PI-containing 15% by weight of ruthenium iodide ratio of about 88%). 19) solution. Take a small amount of the polyimine solution, add γ-butyrolactone, and prepare a solution with a concentration of 10% by weight of polyimine, and the viscosity of the solution is determined to be 90 mPa. s.

Example 1 <Modulation of liquid crystal alignment agent>

The polyiminoimine (PI-2)-containing solution prepared in the above Synthesis Example 3 in an amount equivalent to 20 parts by weight of polyethylenimine (PI-2) is converted into poly-proline (PA- 1) A solution containing poly-proline (PA-1) prepared in the above Synthesis Example 12 in an amount equivalent to 80 parts by weight is mixed with γ-butyrolactone: N-methyl-2-pyrrolidone: butyl The ratio of the fine agent is 71:17:12 by weight, and γ-butyrolactone, N-methyl-2-pyrrolidone and butyl cellosolve are added thereto, and 2 parts by weight of an epoxy group as an adhesion enhancer is further added. The compound N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane was formulated into a solution having a solid content concentration of 3.5% by weight. After the solution was thoroughly stirred, it was filtered through a filter having a pore size of 1 μm to prepare a liquid crystal alignment agent.

The liquid crystal alignment agent was used for evaluation as follows.

<Manufacture and evaluation of liquid crystal display elements> [Manufacture of liquid crystal display elements] (1) Coating of liquid crystal alignment agent and formation of liquid crystal alignment film

The above-prepared liquid crystal alignment agent was coated to a thickness of 1 mm by a spin coater at a rotation speed of 2000 rpm and a rotation time of 20 seconds. The transparent conductive film made of an ITO film provided on one surface of the glass substrate was prebaked on a hot plate at 80 ° C for 1 minute, and then post-baked at 200 ° C for 1 hour to form a coating film having a film thickness of 0.08 μm.

(2) Grinding treatment

The coating film was sanded at a roller rotation speed of 400 rpm, a table moving speed of 3 cm/sec, and a fluffing length of 0.4 mm, using a sanding machine equipped with a roller of rayon cloth. A liquid crystal alignment energy is generated thereon to form a liquid crystal alignment film.

(3) Washing and drying of a substrate coated with a liquid crystal alignment film

The substrate having the liquid crystal alignment film prepared above was ultrasonically washed in ultrapure water for 1 minute, and then dried in a clean oven at 100 ° C for 10 minutes. The same operation was repeated to produce two (a pair of) substrates having a liquid crystal alignment film.

(4) Liquid crystal injection step, bonding and bonding of polarizers

Then, on each of the outer edges of the pair of liquid crystal alignment films having the liquid crystal alignment film, an epoxy resin adhesive having an alumina ball having a diameter of 5.5 μm is applied, and the liquid crystal alignment film faces are relatively overlapped. And press to cure the adhesive. Next, a nematic liquid crystal (manufactured by Merck, MLC-6221) having a positive dielectric anisotropy is filled between the substrates by a liquid crystal injection port, and then the liquid crystal injection port is closed with an acrylic photocurable adhesive. A polarizing plate was bonded to both surfaces of the outer side of the substrate to produce a liquid crystal display element.

[Evaluation of liquid crystal display elements] (1) Evaluation of liquid crystal alignment

Observation of liquid crystal display elements fabricated above using an optical microscope At this time, when there was no light leakage, the liquid crystal alignment property was evaluated as "good", and it was confirmed that there was light leakage, and the liquid crystal alignment property was evaluated as "poor". The liquid crystal alignment property of the liquid crystal display element was "good".

(2) Evaluation of heat resistance (heat stress test)

For the liquid crystal display element manufactured above, first, a voltage of 5 V was applied for a time span of 167 msec, the application time was 60 μsec, and then the voltage holding ratio from the voltage release to 167 msec was measured. The value at this time is taken as the initial voltage holding ratio (VHR _BF ). After the VHR _BF was measured, the liquid crystal display element was placed in an oven at 100 ° C, and thermal stress was applied for 1000 hours. Then, after the liquid crystal display element was allowed to stand at room temperature and cooled to room temperature, the voltage holding ratio VHR _AF after the application of the thermal stress was measured. The rate of change of the voltage holding ratio before and after the application of the thermal stress was determined. When the rate of change was less than 5%, the heat resistance was evaluated as "good", and the heat resistance was evaluated as "poor". The heat resistance of the liquid crystal display element was "good".

Example 2~5

The liquid crystal alignment element was prepared and evaluated in the same manner as in Example 1 except that the polymer of the type shown in Table 1 shown in Table 1 was used in each of the polymers. The results are shown in Table 2.

Example 6 <Modulation of liquid crystal alignment agent>

The polyiminoimine (PI-4)-containing solution prepared in the above Synthesis Example 5 in an amount equivalent to 100 parts by weight of polybenrene (PI-4) is used, and N-methyl-2 is added thereto. - pyrrolidone: butyl cellosolve ratio of 50:50 by weight ratio of N-methyl-2-pyrrolidone and butyl cellosolve, and then added 2 parts by weight The epoxy compound N, N, N', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, which is an adhesion enhancer, was formulated into a solution having a solid content concentration of 3.5% by weight. After the solution was thoroughly stirred, it was filtered through a filter having a pore size of 1 μm to prepare a liquid crystal alignment agent.

<Manufacture and evaluation of liquid crystal display elements>

As the liquid crystal, a nematic liquid crystal (manufactured by Merck, MLC-2038) whose dielectric anisotropy is negative is used, and in the production step of the liquid crystal display element, (2) polishing treatment is not performed, except In the same manner as in Example 1, a liquid crystal display device was produced, and liquid crystal alignment properties and heat resistance were evaluated. The results are shown in Table 2.

Examples 7 and 8

The liquid crystal alignment element was prepared and evaluated in the same manner as in Example 6 except that the polymer of the type shown in Table 1 shown in Table 1 was used in each of the polymers. The results are shown in Table 2.

Example 9 <Modulation of liquid crystal alignment agent>

A polyiminoimine (PI-7)-containing solution prepared in Synthesis Example 8 in an amount equivalent to 100 parts by weight, which is converted into polyiminoimine (PI-7), to which 10 as an adhesion enhancer was added Parts by weight of epoxy compound N, N, N', N'-tetraglycidyl-4,4'-diaminodiphenylmethane and 0.75 parts by weight of functional decane compound 3-[2-(3-trimethyl)矽-butyrolactone and butyl cellosolve are added in a weight ratio of γ-butyrolactone:butyl cellosolve of 80:20, A solution having a solid content concentration of 3.5% by weight was prepared. The solution was filtered with a filter having a pore size of 1 μm to prepare Liquid crystal alignment agent.

<Manufacture and evaluation of liquid crystal display elements>

A liquid crystal display element was produced and liquid crystal alignment was performed in the same manner as in Example 1 except that a nematic liquid crystal (manufactured by Merck & Co., MLC-2019) having a positive dielectric anisotropy was used as the liquid crystal. The evaluation of properties and heat resistance is shown in Table 2.

Examples 10 and 11

The liquid crystal alignment element was prepared and evaluated in the same manner as in Example 9 except that the polymer of the type shown in Table 1 shown in Table 1 was used in each of the polymers. The results are shown in Table 2.

Example 12 <Modulation of liquid crystal alignment agent>

The polyiminoimine (PI-10)-containing solution prepared in the above Synthesis Example 11 in an amount equivalent to 40 parts by weight of polyethylenimine (PI-10) is converted into poly-proline (PA- 4) A solution containing poly-proline (PA-4) prepared in the above Synthesis Example 15 in an amount equivalent to 60 parts by weight is mixed with γ-butyrolactone: N-methyl-2-pyrrolidone: butyl The ratio of the granules is 40:40:20 by weight, and γ-butyrolactone, N-methyl-2-pyrrolidone and butyl cellosolve are added thereto, and 10 parts by weight of an epoxy group as an adhesion enhancer is further added. The compound N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane was formulated into a solution having a solid content concentration of 3.5% by weight. After the solution was thoroughly stirred, it was filtered through a filter having a pore size of 1 μm to prepare a liquid crystal alignment agent.

The liquid crystal alignment agent was used for evaluation as follows.

<Manufacture and evaluation of liquid crystal display elements>

A liquid crystal display element was produced and liquid crystal alignment was performed in the same manner as in Example 1 except that a nematic liquid crystal (manufactured by Merck & Co., MLC-2019) having a positive dielectric anisotropy was used as the liquid crystal. The evaluation of properties and heat resistance is shown in Table 2.

Comparative example 1~5

The liquid crystal alignment element was prepared and evaluated in the same manner as in Example 1 except that the polymer of the type shown in Table 1 shown in Table 1 was used. The results are shown in Table 2.

Comparative Example 6~8

The liquid crystal alignment element was prepared and evaluated in the same manner as in Example 6 except that the polymer of the type shown in Table 1 shown in Table 1 was used in each of the polymers. The results are shown in Table 2.

Comparative Examples 9 and 10

The liquid crystal alignment element was prepared and evaluated in the same manner as in Example 9 except that the polymer of the type shown in Table 1 shown in Table 1 was used in each of the polymers. The results are shown in Table 2.

Comparative Example 11

The liquid crystal alignment element was prepared and evaluated in the same manner as in Example 12 except that the polymer of the type shown in Table 1 shown in Table 1 was used in each of the polymers. The results are shown in Table 2.

In addition, the "type" column of the adhesiveness enhancer in Table 1 and the abbreviation in the solvent composition have the following meanings, respectively.

<Adhesion enhancer>

Epoxy compound

GAPM: N, N, N', N'-tetraglycidyl-4,4'-diaminodiphenyltoluene

Functional decane compound

MSPP: 3-[2-(3-Trimethoxydecylpropylamino)ethylamino]propyl propionate

<solvent composition>

BL: γ-butyrolactone

NMP: N-methyl-2-pyrrolidone

BC: butyl cellosolve

In addition, the content described in the column of "liquid crystal name" in Table 2 has the following meanings.

6221: MLC-6221 (trade name, produced by Merck)

2038: MLC-2038 (trade name, produced by Merck)

2019: MLC-2019 (trade name, produced by Merck)

Claims (7)

A liquid crystal alignment agent comprising a group selected from the group consisting of polylysine obtained by reacting tetracarboxylic dianhydride with a diamine, and polyamidene obtained by dehydrating and ring-closing the polyaminic acid At least one polymer, wherein the diamine contains a compound having a structure represented by the following formula (A) and two amine groups, and a compound represented by the following formula (D-III), In the formula (D-III), R ⁹ is -O-, -COO-*, -OCO-*, -NHCO-*, -CONH-* or -CO-, wherein, among the above, with "*" a linkage to R ¹⁰ ; R ¹⁰ is a monovalent organic group having a skeleton or group selected from the group consisting of an anthracene skeleton, a trifluoromethylphenyl group, a trifluoromethoxyphenyl group, and a fluorophenyl group, or An alkyl group having 6 to 30 carbon atoms; R ¹¹ is an alkyl group having 1 to 4 carbon atoms; and a3 is an integer of 0 to 3, wherein two of the polyamines are used for synthesizing the polyamic acid. The amine contains 5 to 90 mol% of a compound having the structure represented by the above formula (A) and two amine groups, and 1 to 50 mol% of the compound represented by the above formula (D-III). The liquid crystal alignment agent of the first aspect of the invention, wherein the structure represented by the above formula (A) is at least one selected from the group consisting of structural structures represented by the following formulas (A-1) to (A-3). structure, R ^a in the formula (A-1) is ^a halogen atom, a cyano group, an isocyano group, -OCN, -NCO, -SCN, -NCS or an azide group, and n is an integer of 0 to 3, and "*" represents each Is a linkage; R ^b and R ^c in the formulae (A-2) and (A-3) are each independently a hydrogen atom, a halogen atom, a cyano group, an isocyano group, -OCN, -NCO, -SCN, - NCS or azide group, "*" are each represented as a linkage. The liquid crystal alignment agent of the second aspect of the invention, wherein the compound having the structure represented by the above formula (A) and two amine groups is selected from the following formulas (A-1-1) and (A-2-1). And at least one of the groups consisting of the compounds represented by (A-3-1), R ^a and n in the formula (A-1-1) are the same as defined in the above formula (A-1), and Y ^a is a single bond or an extended aryl group having 6 to 10 carbon atoms; R ^b and R ^{c in} 2-1) and (A-3-1) are the same as defined in the above formula (A-2) or (A-3), respectively, and Y ^b and Y ^c are each independently a single bond. Or an extended aryl group having 6 to 10 carbon atoms. The liquid crystal alignment agent of claim 1, wherein R ⁹ in the above formula (D-III) is -O- or -COO-*, wherein a bond having a "*" is bonded to R ¹⁰ , R ¹⁰ It is a monovalent organic group having a steroid skeleton. The liquid crystal alignment agent according to any one of claims 1 to 4, wherein the diamine further contains a selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, and 4,4'-diamine. At least one of the group consisting of bisphenyl ether and bis[4-(4-aminophenoxy)phenyl]anthracene. A liquid crystal alignment agent according to any one of claims 1 to 4, Wherein the tetracarboxylic dianhydride comprises a 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4,5 , 9b-hexahydro-8-methyl-5-(tetrahydro-2,5-di-oxo-3-furanyl)-naphthalene [1,2-c]-furan-1,3-dione and benzene At least one of the group consisting of tetracarboxylic acid dianhydride. A liquid crystal display element comprising a liquid crystal alignment film formed of the liquid crystal alignment agent according to any one of claims 1 to 6.