KR20080011118A - Liquid crystal aligning agent, liquid crystal aligning film and liquid crystal display device - Google Patents

Abstract

A liquid crystal aligning agent, a liquid crystal alignment layer formed from the liquid crystal aligning agent, and an LCD device containing the alignment layer are provided to improve voltage holding ratio and baking characteristics. A liquid crystal aligning agent comprises a poly(amic acid) and/or its imidized polymer; and a compound represented by the formula 1, wherein X is -C(R5)(R6)-, -N(R7)-, -O-, -S-, -S(O)- or -SO2-; R1 to R4 are independently H or a monovalent aliphatic group; and R5 to R7 are independently H or a monovalent organic group. Preferably the compound represented by the formula 1 is represented by the formula 1b.

Description

Liquid crystal aligning agent, liquid crystal aligning film, and liquid crystal display element {LIQUID CRYSTAL ALIGNING AGENT, LIQUID CRYSTAL ALIGNING FILM AND LIQUID CRYSTAL DISPLAY DEVICE}

This invention relates to a liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element. More specifically, it is related with the liquid crystal aligning agent which is favorable for baking characteristic, the liquid crystal aligning film obtained from this liquid crystal aligning agent, and the liquid crystal display element provided with this film, regardless of the electrode type which comprises a liquid crystal display element.

Conventionally, a layer of a nematic liquid crystal having positive dielectric anisotropy is formed between two substrates on which a liquid crystal alignment film is formed on the surface through a transparent conductive film to form a sandwich cell, and the long axis of the liquid crystal molecules is from one substrate to the other. TN type liquid crystal display elements having a TN (Twisted Nematic) type liquid crystal cell which is continuously twisted 90 degrees toward the substrate are known.

In addition, the addition of the chiral agent achieves a state in which the long axis of the liquid crystal molecules are continuously twisted over 180 degrees between the substrates, and STN (Super Twisted Nematic) type using the birefringence effect thus produced. Liquid crystal display elements also exist. Moreover, recently, the nematic liquid crystal layer and the spiral axis of a homeotropic alignment state which have negative dielectric anisotropy between opposing board | substrates form the cholesteric liquid crystal layer in parallel with a board | substrate normal, and pigment | dye in these liquid crystal layers Also, a guest-host type reflective liquid crystal display device having been added has been developed. Orientation of the liquid crystal in these liquid crystal display elements is normally expressed by the liquid crystal aligning film in which the rubbing process was performed. Here, as a material of the liquid crystal aligning film which comprises a liquid crystal display element, polyimide, polyamide, polyester, etc. are known conventionally. In particular, since polyimide is excellent in heat resistance, affinity with a liquid crystal, mechanical strength, etc., it is used for many liquid crystal display elements.

Until now, studies on improvement of display quality, low power consumption, and the like, including high-precision miniaturization of liquid crystal display devices have been conducted, resulting in remarkable developments as high-performance display devices, and having high voltage retention and high reliability as disclosed in Patent Document 1. Liquid crystal display devices have been developed. However, in recent years, in addition to the conventional transmission type, the use range of the liquid crystal display element like the reflection type and the transflective type is also expanding. Accordingly, the performance required for the liquid crystal alignment film is also becoming more and more stringent. In particular, in the low voltage drive type liquid crystal display element for the purpose of low power consumption, the request | requirement for baking characteristics became strict, and the performance which the conventional liquid crystal display element has is not enough. In the liquid crystal aligning film containing the polyamic acid which is a precursor of the polyimide so far, and the imide type polymer which has a structure obtained by dehydrating and ring-closing it, etc., when the liquid crystal display element was manufactured using this liquid crystal aligning film, although the liquid crystal aligning ability is excellent, While sufficient voltage retention was obtained, there were many problems with baking characteristics.

[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2001-228481

The objective of this invention is providing the liquid crystal aligning agent which can express high voltage retention and provides the liquid crystal aligning film with favorable baking characteristic.

Another object of the present invention is to provide a liquid crystal aligning film obtained from the liquid crystal aligning agent and having excellent performance as described above.

Another object of the present invention is to provide a liquid crystal display device comprising the liquid crystal alignment film of the present invention.

Still other objects and advantages of the present invention will become apparent from the following description.

The object and advantages of the present invention, firstly, according to the present invention,

It is achieved by the liquid crystal aligning agent characterized by containing a polyamic acid and / or its imidation polymer, and the compound represented by following formula (1).

또는

이고, R₁ 내지 R₄는 서로 독립적으로 수소 원자 또는 1가의 지방족기이고, R₅ 내지 R₇은 서로 독립적으로 수소 원자 또는 1가의 유기기이다.Where X is

or

R ₁ to R ₄ are each independently a hydrogen atom or a monovalent aliphatic group, and R ₅ to R ₇ are each independently a hydrogen atom or a monovalent organic group.

The above objects and advantages of the present invention are second,

It is achieved by the liquid crystal aligning film formed from the liquid crystal aligning agent of this invention.

Thirdly, the object and advantages of the present invention are:

It is achieved by the liquid crystal display element provided with the liquid crystal aligning film of this invention.

The liquid crystal aligning film formed by the liquid crystal aligning agent of this invention is excellent in baking characteristics compared with the conventional alignment film, and various liquid crystals, such as a TN type liquid crystal display element, an STN type liquid crystal display element, a reflective liquid crystal display element, and a semi-transmissive liquid crystal display element, It can use suitably in order to comprise a display element.

The liquid crystal display element of this invention can be effectively used for various apparatuses, For example, it is preferable as display apparatuses, such as a table calculator, a wristwatch, a table clock, a mobile telephone, a coefficient display board, a word processor, a personal computer, and a liquid crystal television. Can be used.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The liquid crystal aligning agent in this invention contains the compound represented by the said General formula (hereinafter may be called a specific compound hereafter), and polyamic acid and / or its imidation polymer in the organic solvent preferably, and contains it.

[Specific Compounds]

또는

이다. X가

일 때, 화학식 1은 하기 화학식 1a로 표시된다. 또한, X가

일 때, 화학식 1은 하기 화학식 1b로 표시된다.Certain compounds are represented by Formula 1 above. In Formula 1, X is

or

to be. X

When, Formula 1 is represented by the formula (1a). Also, X

When, Formula 1 is represented by the following formula (1b).

R ₅ , R ₆ and R ₇ are each independently a hydrogen atom or a monovalent organic group. As monovalent organic group, a C1-C12 alkyl group, an alkoxy group, a phenyl group etc. are mentioned, for example. These may be substituted, for example, may be an alkyl group having an epoxy group in R ₇ .

R ₁ to R ₄ are each independently a hydrogen atom or a monovalent aliphatic group. As a monovalent aliphatic group, a C1-C12 alkyl group, a cyclohexyl group, a C1-C12 alkoxy group, a vinyl group, an allyl group, glycidyl group, etc. are mentioned, for example.

As a specific compound, the compound represented by following formula (1a) or (1b) is preferable.

Here, the definitions of R ₁ to R ₆ are the same as in the general formula (1).

Here, the definitions of R ₁ to R ₄ , R ₇ are the same as in the general formula (1).

A specific compound can be used individually or in combination of 2 or more types.

A specific compound can be synthesize | combined using the diamine compound mentioned below as a starting material.

Examples of the diamine compound include 2,8-diaminodibenzofuran, 2,8-diaminodibenzothiophene, 2,8-diaminodibenzothiophene, 3,7-diamino-dibenzothiophene, 3, 7-diamino-2,8-dimethyl-dibenzothiophene, 9,9-dimethyl-2,7-diaminofluorene, 2,7-diaminofluorene, 9,9-diphenyl-2,7 -Diaminofluorene, 3,6-diaminocarbazole, 9-methyl-3,6-diaminocarbazole, 9-ethyl-3,6-diaminocarbazole, 9-phenyl-3,6-dia Minocarbazole etc. are mentioned.

Specific examples of the specific compound include N, N, N, N-tetrapropyl-2,7-diaminofluorene, N, N, N, N-tetracyclohexyl-2,7-diaminofluorene, N, N , N, N-tetraallyl-2,7-diaminofluorene, N, N, N, N-methoxymethyl-2,7-diaminofluorene, N, N, N, N-tetraglycidyl -2,7-diaminofluorene, N, N, N, N-tetrapropyl-3,6-diaminocarbazole, N, N, N, N-tetracyclohexyl-3,6-diaminocarbazole , N, N, N, N-tetraallyl-3,6-diaminocarbazole, N, N, N, N-N-methoxymethyl-3,6-diaminocarbazole, N, N, N, N- Tetraglycidyl-3,6-diaminocarbazole and the like.

In addition, certain compounds may include 1 to 3 substituents thereof.

The blending ratio of these specific compounds is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight with respect to 100 parts by weight of the polyamic acid or the polyimide polymer.

polymer

The polyamic acid and imidation polymer thereof used for this invention, Preferably it has a repeating unit represented by the following general formula (I-1), the repeating unit represented by the following general formula (I-2), or these both repeating units. For example, the imidation polymer which has a structure obtained by carrying out dehydration ring closure (imidization) of a polyamic acid and / or the said polyamic acid is mentioned. In addition, the "imidized polymer" in this invention includes the thing in which all the repeating units are imidated, and the part imidated partially. In addition, a part of the imide ring may be an isimide ring.

Wherein, P ¹ is a tetracarboxylic acid dianhydride, and the tetravalent organic group removing two anhydride from the water, and Q ¹ is a divalent organic group removing two amino groups from a diamine compound.

Here, P ² is a tetracarboxylic acid anhydride tetravalent removing group 2 from a dianhydride and an organic group, and Q ² is a divalent organic group removing two amino groups from a diamine compound.

Preferred polymers in the present invention are polymers having a repeating unit represented by the general formula (I-1) and a repeating unit represented by the general formula (I-2). As a liquid crystal aligning agent which has such a polymer, the polymer of following (1)-(3) is mentioned, for example.

(1) A liquid crystal aligning agent containing both a polyamic acid and an imidation polymer.

(2) The liquid crystal aligning agent containing the prepolymer which has an amic-acid structure, and the block copolymer obtained from the prepolymer which has an imide structure.

(3) The liquid crystal aligning agent containing the imidation polymer obtained by partially dehydrating and ring-closing a polyamic acid.

Among these, (1) and (2) are preferable and (1) is especially preferable.

Polyamic acid

The polyamic acid used for this invention is obtained by making tetracarboxylic dianhydride and diamine react.

Tetracarboxylic dianhydride

As tetracarboxylic dianhydride used for the synthesis | combination of the said polyamic acid, butane tetracarboxylic dianhydride, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2-dimethyl, for example. -1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2 , 3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4- Cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3, 5-tricarboxycyclopentylacetic dianhydride, 3,5,6-tricarboxynorbornane-2-acetic dianhydride, 2,3,4,5-tetrahydrofuranthratecarboxylic dianhydride, 1,3, 3a, 4,5,9b-hexahydro-5 (tetrahydro-2,5-dioxo-3- Furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5-methyl-5 (tetrahydro-2,5- Dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5-ethyl-5 (tetrahydro -2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-7-methyl -5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexa Hydro-7-ethyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4, 5,9b-hexahydro-8-methyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3 , 3a, 4,5,9b-hexahydro-8-ethyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3- Dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5 (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] Furan-1,3-dione, 5- (2,5-dioxotetrahydrofural) -3-methyl-3-cyclohexene-1,2-dicarboxy Acid dianhydrides, bicyclo [2,2,2] -oct-7-ene-2,3,5,6-tetracarboxylic dianhydrides, compounds represented by the following formulas (I) and (II) Aliphatic and alicyclic tetracarboxylic dianhydrides such as;

(In formula, R <^1> and R <^3> represents the divalent organic group which has an aromatic ring, R <^2> and R <^4> represents a hydrogen atom or an alkyl group, and ^two or more R <^2> and R <^4> may be same or different, respectively.)

Pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylsulfontetracarboxylic dianhydride, 1,4,5 , 8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenylethertetracarboxylic dianhydride, 3,3 ', 4,4'-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3', 4,4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic Acid dianhydrides, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfide dianhydrides, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydrides, 4 , 4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ', 4,4'-perfluoroisopropylidenediphthalic dianhydride, 3,3', 4,4 '-Biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphineoxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4'-diphenyl ether dianhydride, bis (triphenylphthalic acid) -4,4'-diphenylmethane dianhydride, Ethylene glycol bis (anhydrotrimelitate), propylene glycol bis (anhydro trimellitate), 1,4-butanediol-bis (anhydro trimellitate), 1,6-hexanediol-bis (anhydro Trimellitate), 1,8-octanediol-bis (anhydro trimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis (anhydro trimellitate), the following formulas (1) to Aromatic tetracarboxylic dianhydrides, such as a compound represented by each of (4), are mentioned. These are used individually by 1 type or in combination of 2 or more types.

Among them, butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride , 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 5- (2,5-dioxotetrahydrofural) -3-methyl- 3-cyclohexene-1,2-dicarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl)- Naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3 -Furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5- (tetrahydro-2 , 5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, bicyclo [2,2,2] -oct-7-ene-2,3,5 , 6-tetracarboxylic dianhydride, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenylsulfone Tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, a compound represented by the following formulas (5) to (7) among the compounds represented by the formula (I) and the formula ( The compound represented by following General formula (8) among the compound represented by II) is preferable at the point which can express favorable liquid-crystal orientation. As particularly preferred, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5,9b-hexahydro- 5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro -8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, pyromellitic dianhydride and the formula The compound represented by each of 5) is mentioned.

[Diamine]

As a diamine used for the synthesis | combination of the said polyamic acid, p-phenylenediamine, m-phenylenediamine, 4,4'- diamino diphenylmethane, 4,4'- diamino diphenyl ethane, 4, 4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, 4, 4'-diaminodiphenylether, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl , 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 3,3'-ditrifluoromethyl-4,4'-diaminobiphenyl, 5-amino-1- ( 4'-aminophenyl) -1,3,3-trimethylindane, 6-amino-1- (4'-aminophenyl) -1,3,3-trimethylindane, 3,4'-diaminodiphenylether, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] sulfone, 1,4-bis (4-aminophenoxy) benzene, 1 , 3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 2,7-diamino Fluorene, 9,9-bis (4-aminophenyl) fluorene, 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, 1, 4,4 '-(p-phenyleneisopropylidene) bisaniline, 4,4'-(m-phenyleneisopropylidene) bisaniline, 2,2'-bis [4- (4-amino-2- Trifluoromethylphenoxy) phenyl] hexafluoropropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-bis [(4-amino-2 Aromatic diamines such as -trifluoromethyl) phenoxy] -octafluorobiphenyl;

1,1-methacrylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 4,4-diaminoheptamethylenediamine , 1,4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindenylenedimethylenediamine, tricyclo [6.2.1.0 ^2,7 ] -undecylene Aliphatic and alicyclic diamines such as dimethyldiamine and 4,4'-methylenebis (cyclohexylamine);

2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 5,6-diamino-2,3-dicyanopyrazine, 5, 6-diamino-2,4-dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-triazine, 1,4-bis (3-aminopropyl) piperazine, 2,4-diamino-6-isopropoxy-1,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4-diamino- 6-phenyl-1,3,5-triazine, 2,4-diamino-6-methyl-s-triazine, 2,4-diamino-1,3,5-triazine, 4,6-dia Mino-2-vinyl-s-triazine, 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-phenylphenanthtridine, 1,4-diaminopiperazine, 3,6-diaminoacridine, bis (4-aminophenyl) phenylamine and compounds represented by the following general formulas (III) to (VI) Diamines having two primary amino groups and a nitrogen atom other than the primary amino group in the molecule;

(Wherein R ⁵ represents a monovalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and X represents a divalent organic group)

(Wherein X represents a divalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, R ⁶ represents a divalent organic group, and a plurality of X can be the same or different)

Mono substituted phenylenediamine represented by the following formula (V);

(Wherein R ⁷ represents a divalent organic group selected from -O-, -COO-, -OCO-, -NHCO-, -CONH- and -CO-, R ⁸ represents a steroid skeleton, a trifluoromethyl group and Monovalent organic group or group having 6 to 30 carbon atoms having a group selected from fluoro groups)

Diaminoorganosiloxane represented by the following general formula (VI);

(In formula, R <^9> represents a C1-C12 hydrocarbon group, two or more R <^9> may be same or different, p is an integer of 1-3, q is an integer of 1-20.)

The compound etc. which are represented by each of following formula (9)-(13) are mentioned. These diamines can be used individually or in combination of 2 or more types.

(Wherein y is an integer from 2 to 12 and z is an integer from 1 to 5)

Among them, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4 '-Diaminobiphenyl, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 2,7-diaminofluorene, 4,4'-diaminodiphenylether, 2, 2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluor Lopropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4,4'-(m-phenylenediisopropylidene) Bisaniline, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy C) biphenyl, a compound represented by each of formulas (9) to (13), 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6- Diaminoacridine Of the compounds represented by the formula (III), the compound represented by the following formula (14), the compound represented by the formula (15) among the compounds represented by the formula (IV) and the compound represented by the formula (V) Dodecaneoxy-2,4-diaminobenzene, pentadecaneoxy-2,4-diaminobenzene, hexadecaneoxy-2,4-diaminobenzene, octadecaneoxy-2,5-diaminobenzene, Dodecaneoxy-2,5-diaminobenzene, pentadecaneoxy-2,5-diaminobenzene, hexadecaneoxy-2,5-diaminobenzene, octadecaneoxy-2,5-diaminobenzene, The compound represented by each of (16)-(23) is preferable.

[Synthesis of Polyamic Acid]

The use ratio of the tetracarboxylic dianhydride and the diamine compound provided in the polyamic acid synthesis reaction is preferably such that the acid anhydride group of the tetracarboxylic dianhydride is 0.2 to 2 equivalents to 1 equivalent of the amino group contained in the diamine compound. More preferably, it is the ratio which becomes 0.3 to 1.2 equivalent.

Synthesis reaction of polyamic acid is performed in organic solvent, Preferably it is -20-150 degreeC, More preferably, it is performed on the temperature conditions of 0-100 degreeC. The organic solvent is not particularly limited as long as it can dissolve the polyamic acid synthesized. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl Aprotic polar solvents such as sulfoxide, γ-butyrolactone, tetramethylurea and hexamethylphosphortriamide; Phenol solvents, such as m-cresol, xylenol, a phenol, and a halogenated phenol, are mentioned. Moreover, it is preferable that the usage-amount (a) of an organic solvent is an amount which will be 0.1-30 weight% with respect to the total amount (a + b) of the total reaction solution (a) of tetracarboxylic dianhydride and a diamine compound.

In the organic solvent, alcohol, ketone, ester, ether, halogenated hydrocarbon, hydrocarbon, and the like, which are poor solvents of polyamic acid, can be used in combination without causing precipitation of the resulting polyamic acid. As a specific example of such a poor solvent, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, ethyl lactate, lactic acid Butyl, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate, diethyl oxalate, diethyl malonate, diethyl Ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol Dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol Noethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o- Dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, etc. are mentioned.

The reaction solution which melt | dissolves a polyamic acid as mentioned above is obtained. The reaction solution is poured into a large amount of poor solvent to obtain a precipitate, and polyamic acid can be obtained by drying the precipitate under reduced pressure. In addition, the polyamic acid can be purified by dissolving the polyamic acid again in an organic solvent and then precipitating with a poor solvent once or several times.

Imidization  polymer

The imidation polymer used for this invention is obtained by dehydrating and ring-closing the polyamic acid obtained by making tetracarboxylic dianhydride and diamine react.

Tetracarboxylic dianhydride

As tetracarboxylic dianhydride used for the synthesis | combination of the said imidation polymer, the compound similar to tetracarboxylic dianhydride used for the synthesis | combination of the polyamic acid mentioned above is mentioned.

As tetracarboxylic dianhydride used for the synthesis | combination of the imidation polymer of this invention, alicyclic tetracarboxylic dianhydride is preferable. As a particularly preferred embodiment, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-fura Nil) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-di Oxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione. Moreover, alicyclic tetracarboxylic dianhydride and other tetracarboxylic dianhydride can be used together.

[Diamine]

As diamine used for the synthesis | combination of the said imidation polymer, the diamine same as the diamine used for the synthesis | combination of the polyamic acid mentioned above is mentioned.

As a diamine used for the synthesis | combination of the imidation polymer of this invention, the diamine represented by the said general formula (V) is preferable. Preferred specific examples include dodecaneoxy-2,4-diaminobenzene, pentadecaneoxy-2,4-diaminobenzene, hexadecaneoxy-2,4-diaminobenzene, octadecaneoxy-2,5-diamino Benzene, dodecaneoxy-2,5-diaminobenzene, pentadecaneoxy-2,5-diaminobenzene, hexadecaneoxy-2,5-diaminobenzene, octadecaneoxy-2,5-diaminobenzene, The compound represented by the said General formula (16)-(23) is mentioned.

Moreover, in the imidation polymer of this invention, the diamine represented by the said general formula (V), and another diamine can be used together. Preferred among other diamines are p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 1,5-diaminonaphthalene, 2,2'- Dimethyl-4,4'-diaminobiphenyl, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 2,7-diaminofluorene, 4,4'-diaminodi Phenylether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy ) Phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4,4'-(m-phenyl Rendiisopropylidene) bisaniline, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexylamine), 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis ( 4-aminophenoxy) biphenyl, a compound represented by each of the formulas (9) to (13), 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopy Midine, 3,6-diaminoacridine, the compound represented by the formula (14) among the compounds represented by the formula (III), the compound represented by the formula (15) among the compounds represented by the formula (IV) Etc. can be mentioned.

In the imidation polymer of this invention, the diamine represented by the said general formula (V) is preferably 0.5 weight% or more, especially preferably 1 weight% or more of all the diamines.

[Synthesis of imidized polymer]

The imidation polymer which comprises the liquid crystal aligning agent of this invention is obtained by dehydrating and ring-closing the said polyamic acid. The dehydration ring closure of the polyamic acid may be achieved by (i) heating the polyamic acid, or (ii) dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring closure catalyst to the solution, and heating it as necessary. Is done.

Preferably the reaction temperature in the method of heating the polyamic acid of said (i) is 50-200 degreeC, More preferably, it is 60-170 degreeC. When reaction temperature is less than 50 degreeC, dehydration ring-closure reaction does not fully advance and when reaction temperature exceeds 200 degreeC, the molecular weight of the imidation polymer obtained may fall.

On the other hand, in the method of adding a dehydrating agent and a dehydration ring-closure catalyst to the solution of the polyamic acid of said (ii), acid anhydrides, such as acetic anhydride, a propionic anhydride, a trifluoroacetic anhydride, can be used as a dehydrating agent, for example. It is preferable that the usage-amount of a dehydrating agent shall be 0.01-20 mol with respect to 1 mol of repeating units of a polyamic acid. As the dehydration ring closure catalyst, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used, for example. However, it is not limited to these. It is preferable that the usage-amount of a dehydration ring-closure catalyst shall be 0.01-10 mol with respect to 1 mol of dehydrating agents used. On the other hand, the same solvent as the organic solvent used for the dehydration ring-closure reaction includes the same solvent as the organic solvent exemplified as being used for the synthesis of the polyamic acid. And the reaction temperature of a dehydration ring-closure reaction becomes like this. Preferably it is 0-180 degreeC, More preferably, it is 10-150 degreeC. Moreover, the imidation polymer can be refine | purified by performing the same operation as the purification method of a polyamic acid with respect to the reaction solution obtained in this way.

The imidized polymer used in the present invention may be one having a low imidization rate, partially dehydrated. The imidation ratio in the imidation polymer used for this invention becomes like this. Preferably it is 80% or more, More preferably, it is 85% or more. Here, "imidation ratio" shall represent the ratio of the number of repeating units which form an imide ring with respect to the total number of repeating units in a polymer in%. At this time, a part of the imide ring may be an isoimide ring.

Terminally modified polymers

The polyamic acid and the imidized polymer may be terminally modified with molecular weight. Such terminal-modified ones can be synthesized by adding an acid anhydride, a monoamine compound, a monoisocyanate compound and the like to the reaction system when synthesizing the polyamic acid. Here, as an acid anhydride, maleic anhydride, a phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n- tetradecyl succinic anhydride, n-hexadecyl succinic anhydride etc. are mentioned, for example. Can be. As the monoamine compound, for example, aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine , n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n -Eicosylamine, etc. are mentioned. Moreover, as a monoisocyanate compound, phenyl isocyanate, naphthyl isocyanate, etc. are mentioned, for example.

Logarithmic viscosity of the polymer

As for the polyamic acid and imidation polymer obtained by making it above, the value of the logarithmic viscosity ((eta) _ln ) becomes like this. Preferably it is 0.05-10 dl / g, More preferably, it is 0.05-5 dl / g.

The value of the logarithmic viscosity (η _ln ) in the present invention uses N-methyl-2-pyrrolidone as a solvent, the viscosity is measured at 30 ° C with respect to a solution having a concentration of 0.5 g / 100 milliliter, and the following equation It is obtained by 1.

LCD Alignment agent

The said (A) polymer and (B) epoxy containing compound melt | dissolve and contain normally the liquid crystal aligning agent of this invention, and are comprised.

The temperature at the time of manufacturing the liquid crystal aligning agent of this invention becomes like this. Preferably it is 0 degreeC-200 degreeC, More preferably, it is 20 degreeC-60 degreeC.

As an organic solvent which comprises the liquid crystal aligning agent of this invention, the solvent similar to the solvent illustrated as what is used for the synthesis reaction of polyamic acid is mentioned. Moreover, the poor solvent illustrated as what can be used together at the time of the synthesis reaction of polyamic acid can also be selected suitably, and can be used together.

Solid content concentration in the liquid crystal aligning agent of this invention is selected in consideration of viscosity, volatility, etc. Preferably it is 1 to 10 weight% of range. That is, although the liquid crystal aligning agent of this invention is apply | coated to the surface of a board | substrate, and the coating film used as a liquid crystal aligning film is formed, when solid content concentration is less than 1 weight%, the film thickness of this coating film becomes too small and it is difficult to obtain a favorable liquid crystal aligning film, solid content concentration When the content exceeds 10% by weight, the film thickness of the coating film is too large to obtain a good liquid crystal aligning film, and the viscosity of the liquid crystal aligning agent is increased, resulting in poor coating properties.

The liquid crystal aligning agent of the present invention may contain an epoxy group-containing compound in terms of improving adhesion to the substrate surface. Examples of such epoxy group-containing compounds include propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, and 1,6-hexanediol. Diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N , N, N ', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N', N'-tetra Glycidyl-4,4'- diamino diphenylmethane etc. are mentioned as a preferable thing. The compounding ratio of these and an epoxy group containing compound becomes like this. Preferably it is 40 weight part or less, More preferably, it is 30 weight part or less with respect to 100 weight part of polymers.

Liquid crystal display element

The liquid crystal display element of this invention can be manufactured by the following method, for example.

(1) The liquid crystal aligning agent of this invention is apply | coated to one surface of the board | substrate with which the patterned transparent conductive film is provided preferably by methods, such as a printing method, and then a coating film is formed by heating a coating surface. Here, as a board | substrate, For example, glass, such as float glass and a soda glass; A transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone and polycarbonate can be used. Examples of the transparent conductive film provided on one surface of the substrate include an NESA film containing tin oxide (SnO ₂ ) (registered trademark of PPG Co., Ltd.), an ITO film containing indium tin oxide (In ₂ O ₃ -SnO ₂ ), and the like. Can be used. The photoetching method and the method using a preliminary mask are used for patterning these transparent conductive films. In application | coating of a liquid crystal aligning agent, in order to make adhesiveness of a board | substrate surface, a transparent conductive film, and a coating film more favorable, you may apply | coat a functional silane containing compound, a functional titanium containing compound, etc. previously on the said surface of a board | substrate. . The heating temperature after liquid crystal aligning agent application becomes like this. Preferably it is 80-300 degreeC, More preferably, it is 120-250 degreeC. In addition, although the liquid crystal aligning agent of this invention containing a polyamic acid forms the coating film used as an oriented film by removing an organic solvent after application | coating, it can also be made into a more imidized coating film by advancing dehydration ring closure by further heating. The film thickness of the coating film formed becomes like this. Preferably it is 0.001-1 micrometer, More preferably, it is 0.005-0.5 micrometer.

(2) The rubbing treatment which rubs the formed coating film surface in the fixed direction with the roll which rolled up the cloth which consists of fibers, such as nylon, rayon, and cotton, for example, is performed. Thereby, the orientation ability of a liquid crystal molecule is provided to a coating film, and it becomes a liquid crystal aligning film.

In addition, ultraviolet rays as disclosed in, for example, Japanese Patent Laid-Open No. 6-222366 or Japanese Patent Laid-Open No. 6-281937 are applied to a liquid crystal alignment film formed by the liquid crystal aligning agent of the present invention. By partially irradiating, a resist film is partially formed on the surface of the liquid crystal aligning film subjected to the treatment such as changing the pretilt angle or the rubbing treatment as disclosed in Japanese Patent Laid-Open No. Hei 5-107544. After the rubbing treatment is performed in a direction different from the rubbing treatment, the resist film is removed to perform the processing such as changing the liquid crystal alignment ability of the liquid crystal alignment film, thereby improving the display characteristics of the liquid crystal display element.

(3) Two board | substrates with a liquid crystal aligning film were manufactured as mentioned above, and two board | substrates were opposingly arranged through a clearance gap (cell spacing) so that the rubbing direction in each liquid crystal aligning film might be orthogonal or antiparallel, The periphery of the substrate is bonded using a sealant, the liquid crystal is injected and filled into the cell gap partitioned by the substrate surface and the sealant, and the injection hole is sealed to form a liquid crystal cell. And a polarizing plate is bonded to the outer surface of the liquid crystal cell, ie, the other surface side of each board | substrate which comprises a liquid crystal cell, by bonding so that the polarization direction may coincide or orthogonally cross with the rubbing direction of the liquid crystal aligning film formed in one surface of the said board | substrate, a liquid crystal display element Is obtained.

Here, as the sealing agent, for example, an epoxy resin containing aluminum oxide spheres as a curing agent and a spacer can be used.

Examples of the liquid crystals include nematic liquid crystals and smectic liquid crystals. Among them, nematic liquid crystals are preferred, and for example, Schiff base liquid crystals, subfamily clock liquid crystals, biphenyl liquid crystals, phenylcyclohexane liquid crystals, ester liquid crystals, A terphenyl type liquid crystal, a biphenyl cyclohexane type liquid crystal, a pyrimidine type liquid crystal, a dioxane type liquid crystal, a bicyclooctane type liquid crystal, a cuban type liquid crystal, etc. can be used. In addition, these liquid crystals are sold, for example, as cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonate and cholesteryl carbonate, and trade names "C-15" and "CB-15" (manufactured by Merck). A chiral agent etc. can also be added and used. Ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate can also be used.

Moreover, as a polarizing plate bonded to the outer surface of a liquid crystal cell, the polarizing plate which sandwiched the polarizing film called H film | membrane which absorbed iodine, and extended | stretched polyvinyl alcohol between the cellulose acetate protective films, or the polarizing plate which consists of H film itself is mentioned. .

<Example>

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not restrict | limited to these Examples. The voltage retention in the Example and the comparative example was evaluated by the following method.

[Voltage retention rate]

After applying a voltage of 5 V to the liquid crystal display element with an application time of 60 microseconds and a spun of 167 milliseconds, the voltage retention after 167 milliseconds from the release of the application was measured. The measurement apparatus used VHR-1 by Toyo Technica. It was judged that the case where the voltage retention was 90% or more was good, and the other cases were defective.

[Bake Test]

A cell having an ITO electrode as shown in FIG. 1 was prepared. DC voltage 6.0V was applied to electrode A and DC voltage 0.5V to electrode B at room temperature for 24 hours. After the stress was released, DC voltages of 0.1 to 5.0 V were applied to the electrodes A and B at 0.1 V intervals. The baking characteristics were judged by the luminance difference between the electrodes A and B at the respective voltages. When the luminance difference was large, it was determined that the baking characteristic was poor.

Synthesis Example 1

112.09 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetra 157.15 g (0.50 mol) of hydro-2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione, 93.54 g (0.865 mol) of p-phenylenediamine as a diamine compound ), 24.85 g (0.10 mol) of 3,3 '-(tetramethyldisiloxane-1,3-diyl) bis (propylamine), and 12.86 g (0.02) of 3,6-bis (4-aminobenzoyloxy) cholestane Mole) and 8.09 g (0.03 mole) of n-octadecylamine were dissolved in 4500 g of N-methyl-2-pyrrolidone as monoamine, and it was made to react at 60 degreeC for 6 hours. The reaction solution was then poured into excess methyl alcohol to precipitate the reaction product. Thereafter, the resultant was washed with methyl alcohol and dried at 40 ° C. for 15 hours under reduced pressure to obtain 380 g of a polyamic acid having a logarithmic viscosity of 0.80 dl / g. 30 g of the obtained polyamic acid was dissolved in 570 g of N-methyl-2-pyrrolidone, and 23.4 g of pyridine and 18.1 g of acetic anhydride were added thereto, followed by dehydration and ring closure at 110 ° C. for 4 hours. Decompression was carried out to obtain 18.6 g of a polyimide having a logarithmic viscosity of 0.78 dl / g (referred to as "polyimide (A-1)").

Synthesis Example 2

1,2,3,4-cyclobutanetetracarboxylic dianhydride 196.12 g (1.0 mole) as tetracarboxylic dianhydride, 2,2'-dimethyl-4,4'-diaminobiphenyl 212.3 as a diamine compound g (1.0 mol) was dissolved in 4500 g of N-methyl-2-pyrrolidone and reacted at 40 ° C for 3 hours. The reaction solution was then poured into a large excess of methyl alcohol to precipitate the reaction product. Thereafter, the resultant was washed with methyl alcohol and dried at 40 ° C. under reduced pressure for 15 hours to obtain 390 g of a polyamic acid having a logarithmic viscosity of 0.91 dl / g (this is referred to as “polyamic acid (B-1)”).

Synthesis Example 3

10 g (0.051 mol) of 2,7-diaminofluorene, 3.8 g (0.041 mol) of epichlorohydrin, 100 ml of tetrahydrofuran and 4.5 ml of water were mixed and stirred at 80 ° C. for 4 hours. After the reaction temperature was lowered to 60 ° C, 10 g of a 50% aqueous NaOH solution was added dropwise. After heating and stirring for 4 hours, unreacted epichlorohydrin was distilled off under reduced pressure. The residue was separated and washed with toluene / water, and the solvent was distilled off to obtain 13.9 g of the desired epoxy (C-1).

Synthesis Example 4

In the synthesis example 3, 12.9 g of the target epoxy bodies (C-2) were obtained by using 10.06 g (0.051 mol) of 3,6-diaminocarbazoles instead of 2,7-diaminofluorene.

Example 1

(Gamma) -butyrolactone / N-methyl so that the polyimide (A-1) obtained by the synthesis example 1 and the polyamic acid (B-1) obtained by the synthesis example 2 become polyimide: polyamic acid = 20: 80 (weight ratio). It dissolved in the 2-pyrrolidone / butyl cellosolve mixed solvent (weight ratio 71/17 / l2). The epoxy substance (C-1) was melt | dissolved in this solution so that it might be 15 weight part with respect to 100 weight part of polymers, and it was set as the solution of 3.5 weight% of solid content concentration. After sufficient stirring, the solution was filtered using a filter having a pore diameter of 1 m to prepare a liquid crystal aligning agent of the present invention. The liquid crystal aligning agent was applied (spinning speed: 2,500 rpm, coating time: 1 minute) using a spinner on a transparent conductive film made of an ITO film provided on one surface of a glass substrate having a thickness of 1 mm, and then used at 200 ° C for 1 hour. By drying, a film having a dry film thickness of 0.08 mu m was formed. By the rubbing machine which has the roll which wound the cloth made from rayon on this film, the rubbing process was performed by roll rotation speed 400rpm, stage movement speed | rate 3cm / sec, hairpin indentation length 0.4mm. The liquid crystal aligning film coated substrate was immersed in isopropyl alcohol for 1 minute, and then dried for 5 minutes on a hot plate at 100 ° C. Next, after apply | coating the aluminum oxide sphere containing epoxy resin adhesive of diameter 5.5micrometer to each outer edge which has a liquid crystal aligning film of the said liquid crystal aligning film application board | substrate of a pair of transparent electrode / transparent electrode board | substrate, so that a liquid crystal aligning film surface may mutually face each other. It was overlapped and pressed, and the adhesive was hardened. Subsequently, after filling a nematic liquid crystal (MLC-6221 made by Merck Co., Ltd.) between a liquid crystal injection hole and a board | substrate, the liquid crystal injection hole is sealed with an acryl-type photocuring adhesive agent, a polarizing plate is bonded to the outer both sides of a board | substrate, and a liquid crystal display element is manufactured. It was. The voltage retention of the obtained liquid crystal display element was evaluated. The liquid crystal aligning agent obtained by this invention showed the high voltage retention of 99% or more. Moreover, as a result of the baking test, favorable results were shown.

Example 2

It carried out similarly to Example 1 except having used the epoxy body (C-2) instead of the epoxy body (C-1). The results are shown in Table 1.

Comparative Example 1

It carried out similarly to Example 1 except having produced the liquid crystal display element without using an epoxy body. And voltage retention and baking characteristics were evaluated. The results are shown in Table 1.

1 is an explanatory diagram of a cell used in the baking test.

Claims (5)

A polyamic acid and / or its imidation polymer, and the compound represented by following formula (1) are contained, The liquid crystal aligning agent characterized by the above-mentioned. <Formula 1>

Where X is

or

R ₁ to R ₄ are each independently a hydrogen atom or a monovalent aliphatic group, and R ₅ to R ₇ are each independently a hydrogen atom or a monovalent organic group. The liquid crystal aligning agent of claim 1, wherein the compound represented by Chemical Formula 1 is represented by the following Chemical Formula 1a. <Formula 1a>

Here, the definitions of R ₁ to R ₆ are the same as in the general formula (1). The liquid crystal aligning agent of claim 1, wherein the compound represented by Chemical Formula 1 is represented by the following Chemical Formula 1b. <Formula 1b>

Here, the definitions of R ₁ to R ₄ and R ₇ are the same as in the general formula (1). The liquid crystal aligning film formed from the liquid crystal aligning agent of any one of Claims 1-3. The liquid crystal display element provided with the liquid crystal aligning film of Claim 4.

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