JP2009294281A - Liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal aligning agent which provides a liquid crystal alignment film having excellent liquid crystal alignment capability and seize resistance, and further which has an excellent coating property. <P>SOLUTION: The liquid crystal aligning agent includes an imidized polymer produced by dehydration ring-closing of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride with a diamine containing at least one selected from a group comprising 1,3-bis(4-aminophenoxy) benzene, 1,3-bis(3-aminophenoxy) benzene, 1,4-bis(4-aminophenoxy) benzene, bis[4-(4-aminophenoxy) phenyl] ether, and 4,4'-bis(4-aminophenoxy) biphenyl, of 3-30 mol% with respect to the total diamine. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, and a liquid crystal display element.

Currently, as a liquid crystal display element, a liquid crystal alignment film is formed on the surface of a substrate on which a transparent conductive film is provided to form a substrate for a liquid crystal display element. A so-called TN type (twisted nematic) in which the long axis of liquid crystal molecules is continuously twisted by 90 ° from one substrate to the other substrate. ) TN type liquid crystal display element having a liquid crystal cell, STN (Super Twisted Nematic) type liquid crystal display element capable of realizing a high contrast ratio as compared with TN type liquid crystal display element, and IPS (In-Plane Switching) type having less viewing angle dependency Optical compensation bend (Optical) with low viewing angle dependency and excellent high-speed response of video screen y Compensated Birefringence = OCB) type liquid crystal display device, such as a VA (Vertical Alignment) type liquid crystal display device using a nematic liquid crystal is known to have a negative dielectric anisotropy (Patent Documents 1 to 5).
As materials for the liquid crystal alignment film in these liquid crystal display elements, polyimide, polyamide, polyester, and the like are conventionally known, but in particular, polyimide has excellent heat resistance, affinity with liquid crystals, mechanical strength, It is used in many liquid crystal display elements (Patent Document 6).
Such a liquid crystal alignment film is required to have good liquid crystal alignment performance (pretilt angle developability) and performance such that image sticking does not occur even after long-time driving.

By the way, in recent years, liquid crystal display elements have been increasing in aperture ratio and resolution in order to obtain brighter and more beautiful images. Further, with the development of larger screens and moving image fixing technology, liquid crystal display elements have been required to have finer and more beautiful displays. For this reason, the liquid crystal alignment film is required to have a high degree of uniformity over the entire surface of the film as well as the above-mentioned various performances. In particular, a high degree of applicability (printability) in offset printing, which is widely adopted in the liquid crystal alignment film forming process, is required.
However, a material satisfying a high degree of applicability without impairing the various performances conventionally required for the liquid crystal alignment film has not yet been known. In addition, due to the increase in the substrate area accompanying the recent increase in the size of liquid crystal panels, the demand for coating properties has become even stronger. In particular, the tact time specific to large lines (after applying the liquid crystal aligning agent, proceed to the pre-baking process. It is required to minimize the impact of extending the time until
In particular, in the case of polyimide, it is believed that good liquid crystal alignment performance and image sticking properties and high coating properties are in a trade-off relationship, and materials that satisfy both of these demands are eagerly desired.
JP-A-4-153622 JP 60-107020 A Japanese Patent Laid-Open No. 7-261181 Japanese Patent Laid-Open No. 11-258605 JP 2007-9031 A Japanese Patent Laid-Open No. 62-165628 JP 2002-327058 A JP-A-6-222366 JP-A-6-281937 JP-A-5-107544

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a liquid crystal aligning agent that can provide a liquid crystal aligning film having good liquid crystal aligning performance and image sticking characteristics and that has a high degree of applicability. There is.
Another object of the present invention is to provide a liquid crystal alignment film having good liquid crystal alignment performance and image sticking characteristics.
Still another object of the present invention is to provide a liquid crystal display element excellent in display quality capable of high-definition display.
Further objects and advantages of the present invention will become apparent from the following description.

In accordance with the present invention, the above objects and advantages of the present invention are primarily as follows:
Tetracarboxylic dianhydride;
1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl The polyamic acid obtained by reacting a diamine containing 3 to 30 mol% of at least one selected from the group consisting of ether and 4,4′-bis (4-aminophenoxy) biphenyl with respect to the total diamine is dehydrated and cyclized. This is achieved by a liquid crystal aligning agent containing an imidized polymer.
The above objects and advantages of the present invention are, secondly,
Achieved by a liquid crystal alignment film formed from the above liquid crystal aligning agent,
This is achieved by a liquid crystal display device comprising the liquid crystal alignment film.

The liquid crystal aligning agent of this invention is excellent in applicability | paintability, and can give the liquid crystal aligning film which has the high degree of uniformity over the whole film surface.
The liquid crystal alignment film of the present invention formed from the liquid crystal aligning agent of the present invention has excellent liquid crystal alignment properties, and has a characteristic that image sticking is rapidly relieved as stress and stress are released by voltage and heat. It can be suitably applied.
The liquid crystal display element of the present invention having such a liquid crystal alignment film of the present invention is capable of high-definition display and is excellent in display quality. Therefore, the display device of the present invention can be suitably used for various devices such as a display device such as a desk calculator, a wristwatch, a table clock, a counting display board, a word processor, a personal computer, and a liquid crystal television.

Hereinafter, the present invention will be described in detail.
The liquid crystal aligning agent of the present invention comprises tetracarboxylic dianhydride,
1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl The polyamic acid obtained by reacting a diamine containing 3 to 30 mol% of at least one selected from the group consisting of ether and 4,4′-bis (4-aminophenoxy) biphenyl with respect to the total diamine is dehydrated and cyclized. Containing an imidized polymer.
<Imidized polymer>
[Tetracarboxylic dianhydride]
Examples of the tetracarboxylic dianhydride used for synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention include, for example, butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic Acid dianhydride, 1,2-dimethyl-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-tri-carboxy-norbornane-2-acetic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic 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, , 3,3a, 4,5,9b-Hexahydro-7-ethyl-5- (teto Hydro-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-dioxotetrahydrofuranyl) -3- Methyl-3-cyclohexene-1,2-dicarboxylic anhydride, bi Chlo [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), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride 3,5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3 , 5, 8, 10-tetraone, the following formulas (TI) and (T-II)

(In the formulas (T-I) and (T-II), R ¹ and R ³ are each a divalent organic group having an aromatic ring, and R ² and R ⁴ are each a hydrogen atom or an alkyl group. And a plurality of R ² and R ⁴ may be the same or different.)
An aliphatic or alicyclic tetracarboxylic dianhydride such as a compound represented by each of the following:
Pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfone tetracarboxylic dianhydride, 1,4,5, 8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyl ether tetracarboxylic dianhydride, 3,3 ′, 4,4′-dimethyldiphenylsilanetetracarboxylic dianhydride, 3,3 ′, 4,4′-tetraphenylsilanetetracarboxylic dianhydride, 1,2,3,4-furantetracarboxylic dianhydride 4,4′-bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 4,4′-bis (3,4-dicarboxyphenoxy) diphenylsulfone dianhydride, 4,4′-bis ( 3,4-dicar Boxyphenoxy) diphenylpropane dianhydride, 3,3 ′, 4,4′-perfluoroisopropylidene diphthalic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2 , 2 ′, 3,3′-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis ( Triphenylphthalic acid) dianhydride, bis (triphenylphthalic acid) -4,4′-diphenyl ether dianhydride, bis (triphenylphthalic acid) -4,4′-diphenylmethane dianhydride, ethylene glycol-bis ( Anhydrotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4-butanediol-bis (anhydrotrimellitate) Retate), 1,6-hexanediol-bis (anhydrotrimellitate), 1,8-octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis ( Anhydrotrimellitate), the following formulas (T-1) to (T-4)

An aromatic tetracarboxylic dianhydride such as a compound represented by each of the above can be exemplified. These can be used individually by 1 type or in combination of 2 or more types.
Specific examples of the compound represented by the above formula (TI) include, for example, the following formulas (T-5) to (T-7):

Specific examples of the compound represented by the above formula (T-II) include, for example, the following formula (T-8):

Can be mentioned respectively. Of these, alicyclic tetracarboxylic dianhydrides are preferred.
The tetracarboxylic dianhydride used for synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention is, in particular, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a. , 4,5,9b-Hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [ 3.2.1] Octane-2,4-dione-6-spiro-3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3 -Methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride and 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] preferably includes at least one selected from the group consisting of undecane-3,5,8,10-tetraone (hereinafter referred to as “specific tetracarboxylic dianhydride (1)”). , 3,5-tricarboxycyclopentylacetic acid dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1 , 2-c] -furan-1,3-dione, more preferably at least one selected from the group consisting of 2,3,5-tricarboxycyclopentylacetic dianhydride and 1,3,3a, 4,5,9b-Hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3- It preferably contains both diones.
The tetracarboxylic dianhydride used to synthesize the polyamic acid contains 30 mol% or more of the specific tetracarboxylic dianhydride (1) as described above with respect to the total tetracarboxylic dianhydride. It is preferable that 50 mol% or more is included, and 80 mol% or more is more preferable.

[Diamine]
The diamine used for synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention is 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, At least one selected from the group consisting of 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] ether and 4,4′-bis (4-aminophenoxy) biphenyl 3-30 mol% with respect to diamine, Preferably it contains 5-20 mol%.
When synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4- Other diamines used together with at least one selected from the group consisting of bis (4-aminophenoxy) benzene and bis [4- (4-aminophenoxy) phenyl] ether, 4,4′-bis (4-aminophenoxy) biphenyl For example, p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylethane, 4,4′-diaminodiphenyl sulfide, 4,4′-diaminodiphenylsulfone, 3 , 3′-dimethyl-4,4′-diaminobiphenyl, 4,4′-diaminodiphenyl ether, 1, -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 ′ -Diaminodiphenyl ether, 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, 4,4′-bis (4-aminophenoxy) biphenyl, 1,3-bis (4-amino) Enoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 2,7-diaminofluorene, 9,9-dimethyl-2,7 -Diaminofluorene, 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-trifluoromethylpheno) C) phenyl] hexafluoropropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octa Fluorobibiphenyl, the following formulas (D-1) and (D-2)

(Y in formula (D-1) is an integer of 2 to 12, and z in formula (D-2) is an integer of 1 to 5.)
An aromatic diamine such as a compound represented by each of the following:

1,1-metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 4,4-diaminoheptamethylenediamine, 1 , 4-diaminocyclohexane, isophoronediamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindanylene methylenediamine, tricyclo [6.2.1.0 ^2,7 ] -undecylenedimethyldiamine, 4 Aliphatic or cycloaliphatic diamines such as 1,4′-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane;
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-diamino-2-vinyl-s-triazine, 2,4-diamino-5-phenylthiazole, 2,6- Aminopurine, 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-diaminopiperazine, 3,6-diaminoacridine, bis (4-aminophenyl) phenylamine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl -3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N, N'-bis (4-aminophenyl) -benzidine, N, N'-bis (4-aminophenyl) -N, N '-Dimethyl-benzidine and the following formula (DI)

(In the formula (DI), R ⁵ is a monovalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and 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 formula (D-II):

(In formula (D-II), R ⁷ is a divalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and X ² is a divalent organic group, respectively. A plurality of X ² may be the same or different, R ⁸ is an alkyl group having 1 to 4 carbon atoms, and a2 is an integer of 0 to 3 respectively. is there.)
A diamine having two primary amino groups and a nitrogen atom other than the primary amino group in the molecule, such as a compound represented by:
The following formula (D-III)

(In the formula (D-III), R ⁹ is a divalent linking group selected from —O—, —COO—, —OCO—, —NHCO—, —CONH— and —CO—, and R ¹⁰ is a steroid. R ¹¹ is a monovalent organic group having a skeleton or a group selected from a skeleton, a trifluoromethylphenyl group, a trifluoromethoxyphenyl group and a fluorophenyl group, or an alkyl group having 6 to 30 carbon atoms, and R ¹¹ has 1 to 4 carbon atoms A3 is an integer of 0 to 3.)
Monosubstituted phenylenediamines such as compounds represented by:
The following formula (D-IV)

(In Formula (D-IV), X ³ is a divalent linking group selected from —O—, —COO—, —OCO—, —NHCO—, —CONH—, and —CO—, respectively. ¹² is a divalent organic group having a steroid skeleton, R ¹³ is an alkyl group having 1 to 4 carbon atoms, and a4 is an integer of 0 to 3 respectively.
A compound represented by:
Following formula (D-V)

(In the formula (D-V), each R ¹⁴ is a hydrocarbon group having 1 to 12 carbon atoms, and a plurality of R ¹⁴ may be the same or different, and p is each 1 is an integer of 1 to 3, and q is an integer of 1 to 20.)
And diaminoorganosiloxanes such as compounds represented by the formula:
The benzene ring of the aromatic diamine may be substituted with one or two or more alkyl groups having 1 to 4 carbon atoms (preferably a methyl group). R ⁶ , R ⁸ , R ¹¹ and R ¹³ in the above formulas (D-I), (D-II), (D-III) and (D-IV) are each preferably a methyl group, and a1 , A2, a3 and a4 are each preferably 0 or 1, and more preferably 0.
The steroid skeleton in R ¹⁰ and R ¹² in the above formulas (D-III) and (D-IV) is a structure composed of a cyclopentano-perhydrophenanthrene nucleus or one or more of its carbon-carbon bonds are doubled. A skeleton that is connected. As the monovalent organic group of R ^{10 and} the divalent organic group of R ¹² having such a steroid skeleton, those having 17 to 40 carbon atoms are preferable, and those having 17 to 29 carbon atoms are more preferable.
Specific examples of R ¹⁰ include cholestan-3-yl group, cholesta-5-en-3-yl group, cholesta-24-en-3-yl group, and cholesta-5,24-dien-3-yl group. Specific examples of R ¹² include, for example, cholestane-3,6-diyl group, cholestane-5-ene-3,6-diyl group, cholesta-24-ene-3,6-diyl group, and cholesta-5. , 24-diene-3,6-diyl group, 4,4-dimethylcholestane-2,6-diyl group, cholestane-3,3-diyl group and the like.
Specific examples of the compound represented by the above formula (DI) include, for example, the following formula (D-3):

A compound represented by:
Specific examples of the compound represented by the formula (D-II) include, for example, the following formula (D-4)

A compound represented by:
Specific examples of the compound represented by the above formula (D-III) include dodecanoxy-2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecanoxy-2,4-diaminobenzene, octadecanoxy-2, 4-diaminobenzene, dodecanoxy-2,5-diaminobenzene, pentadecanoxy-2,5-diaminobenzene, hexadecanoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, the following formulas (D-5) to ( D-13)

A compound represented by each of the above;
Specific examples of the compound represented by the above formula (D-IV) include, for example, the following formulas (D-14) to (D-16):

A compound represented by each of the above;
Specific examples of the compound represented by the formula (D-V) include, for example, 1,3-bis (3-aminopropyl) -tetramethyldisiloxane.
Other diamines used for synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention are p-phenylenediamine, 4,4′-diaminodiphenylmethane, and 4,4′-diaminodiphenyl. Sulfide, 1,5-diaminonaphthalene, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-ditrifluoromethyl-4,4′-diaminobiphenyl, 2,7-diaminofluorene, 4, 4′-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) ) Phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 ′-(p-phenylenedi) Propylidene) bisaniline, 4,4 ′-(m-phenylenediisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl, 1,4- Diaminocyclohexane, 4,4′-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane, compounds represented by the above formulas (D-1) and (D-2), 2,6- Diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6- Diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N, N′-bis (4-aminophenyl) Benzidine, N, N′-bis (4-aminophenyl) -N, N′-dimethylbenzidine, a compound represented by the above formula (D-3), a compound represented by the above formula (D-4), the above At least one selected from the group consisting of a compound represented by the formula (D-III), a compound represented by the above formula (D-IV), and 1,3-bis (3-aminopropyl) -tetramethyldisiloxane (Hereinafter referred to as “other specific diamine”).

The other specific diamine is preferably at least one selected from the group consisting of p-phenylenediamine, a compound represented by the above formula (D-III), and a compound represented by the above formula (D-IV). .
The diamine used for synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention preferably contains 20 to 97 mol% of the other specific diamine as described above with respect to the total diamine. The content is preferably 50 to 97 mol%, and more preferably 70 to 97 mol%.
Most preferably, the diamine used for synthesizing the imidized polymer contained in the liquid crystal aligning agent of the present invention,
1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl At least one selected from the group consisting of ether and 4,4′-bis (4-aminophenoxy) biphenyl, based on the total diamine,
40 to 94 mol% of p-phenylenediamine with respect to the total diamine, and at least selected from the group consisting of the compound represented by the above formula (D-III) and the compound represented by the above formula (D-IV) One to 20 mol% of all diamines
Is included.

[Synthesis of imidized polymer]
The imidized polymer contained in the liquid crystal aligning agent of the present invention can be obtained by dehydrating and ring-closing the polyamic acid (intermediate product) obtained by reacting the tetracarboxylic dianhydride and diamine as described above. it can.
The ratio of the tetracarboxylic dianhydride and the diamine compound used in the polyamic acid synthesis reaction is such that the acid anhydride group of the tetracarboxylic dianhydride is 0.001 with respect to 1 equivalent of the amino group contained in the diamine compound. A ratio of 5 to 2 equivalents is preferable, and a ratio of 0.7 to 1.2 equivalents is more preferable.
The polyamic acid synthesis reaction is preferably carried out in an organic solvent under a temperature condition of preferably -20 to 150 ° C, more preferably 0 to 100 ° C. The reaction time is preferably 1 to 30 hours, more preferably 1 to 20 hours. The organic solvent that can be used here is not particularly limited as long as it can dissolve the synthesized polyamic acid. For example, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethyl is used. Examples include aprotic polar solvents such as formamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea and hexamethylphosphortriamide; and phenolic solvents such as m-cresol, xylenol, phenol and halogenated phenol. The amount (a) of the organic solvent used is such that the total amount (b) of the tetracarboxylic dianhydride and the diamine compound is 0.1 to 30% by weight with respect to the total amount (a + b) of the reaction solution. It is preferable. In addition, when using an organic solvent together with the poor solvent demonstrated below, the usage-amount (a) of the said organic solvent should be understood as a total usage-amount of an organic solvent and a poor solvent.

For the organic solvent, alcohol, ketone, ester, ether, halogenated hydrocarbon, hydrocarbon and the like, which are poor solvents for polyamic acid, can be used in combination as long as the polyamic acid to be produced does not precipitate. Specific examples of such poor solvents include methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, ethyl lactate, butyl lactate, acetone, and methyl ethyl ketone. , Methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, 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, Lenglycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4 -Dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, isoamylpropionate, isoamylisobutyrate, diisopentyl ether and the like.
When the organic solvent is used in combination with the poor solvent, the proportion of the poor solvent used is preferably 50% by weight or less, more preferably 30% by weight or less based on the total of the organic solvent and the poor solvent. It is preferably 20% by weight or less.

As described above, a reaction solution obtained by dissolving polyamic acid is obtained. This polyamic acid solution may be used for the dehydration ring-closing reaction in the next step as it is, may be subjected to the dehydration ring-closing reaction after isolating the polyamic acid contained in the reaction solution, or the isolated polyamic acid May be subjected to a dehydration ring closure reaction after purification. The polyamic acid is isolated by pouring the above polyamic acid solution into a large amount of poor solvent to obtain a precipitate, and drying this precipitate under reduced pressure, or by distilling the polyamic acid solution under reduced pressure with an evaporator. It can be carried out. Also, the polyamic acid is purified by a method in which the polyamic acid thus obtained is dissolved again in an organic solvent and then precipitated in a poor solvent, or a method in which the step of distilling off with an evaporator under reduced pressure is performed once or several times. be able to.
The polyamic acid dehydration ring-closing reaction can be obtained by dehydrating and ring-closing the polyamic acid. At this time, all of the amic acid structure may be dehydrated and closed to completely imidize, or only a part of the amic acid structure may be dehydrated and closed to form a partially imidized product in which the amic acid structure and the imide structure coexist. Also good. The imidization rate of the imidized polymer contained in the liquid crystal aligning agent of the present invention is preferably 40% or more, more preferably 80% or more. Here, the “imidation rate” refers to a numerical value representing the ratio of the number of imide ring structures to the total number of amic acid structures and the number of imide ring structures in the imidized polymer as a percentage. At this time, a part of the imide ring may be an isoimide ring.
The polyamic acid is dehydrated and closed by (i) a method of heating the polyamic acid, or (ii) dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring-closing catalyst to this solution, and heating as necessary. It can be done by a method.
The reaction temperature in the method (i) of heating the polyamic acid is preferably 50 to 200 ° C, more preferably 60 to 170 ° C. When the reaction temperature is less than 50 ° C., the dehydration ring-closing reaction does not proceed sufficiently, and when the reaction temperature exceeds 200 ° C., the molecular weight of the imidized polymer obtained may decrease. The reaction time is preferably 1 to 50 hours, more preferably 1 to 30 hours.
On the other hand, in the method (ii) of adding a dehydrating agent and a dehydrating ring-closing catalyst to the polyamic acid solution, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride is used as the dehydrating agent. Can do. The amount of the dehydrating agent used is preferably 0.01 to 20 mol relative to 1 mol of the polyamic acid repeating unit. Moreover, as a dehydration ring closure catalyst, tertiary amines, such as a pyridine, a collidine, a lutidine, a triethylamine, can be used, for example. However, it is not limited to these. The amount of the dehydration ring-closing catalyst used is preferably 0.01 to 10 mol with respect to 1 mol of the dehydrating agent used. In addition, as an organic solvent used for dehydration ring closure reaction, the organic solvent illustrated as what is used for the synthesis | combination of a polyamic acid can be mentioned. And the reaction temperature of dehydration ring closure reaction becomes like this. Preferably it is 0-180 degreeC, More preferably, it is 10-150 degreeC. The reaction time is preferably 1 to 20 hours, more preferably 1 to 10 hours.

  The imidized polymer obtained in the above method (i) may be used for the preparation of a liquid crystal aligning agent as it is, or may be used for the preparation of a liquid crystal aligning agent after purifying the obtained imidized polymer. . On the other hand, in the method (ii), a reaction solution containing an imidized polymer is obtained. This reaction solution may be directly used for the preparation of the liquid crystal aligning agent, or may be used for the preparation of the liquid crystal aligning agent after removing the dehydrating agent and the dehydrating ring-closing catalyst from the reaction solution. After separating, it may be used for preparing a liquid crystal aligning agent, or the isolated imidized polymer may be purified and then used for preparing a liquid crystal aligning agent. In order to remove the dehydrating agent and the dehydrating ring-closing catalyst from the reaction solution, for example, a method such as solvent replacement can be applied. Isolation and purification of the imidized polymer can be performed in the same manner as in the isolation and purification of the polyamic acid, respectively.

[Terminal-modified imidized polymer]
The imidized polymer contained in the liquid crystal aligning agent of the present invention may be a terminal modified type having a molecular weight adjusted. Such a terminal-modified polymer can be synthesized by adding an appropriate molecular weight regulator such as acid monoanhydride, monoamine compound, monoisocyanate compound to the reaction system when synthesizing the polyamic acid. . Here, as the acid monoanhydride, for example, maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl succinic anhydride , N-hexadecyl succinic anhydride and the like. Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, Examples include n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, and n-eicosylamine. it can. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate. The use ratio of the molecular weight regulator as described above is preferably 10 parts by weight or less, more preferably 100 parts by weight or less, more preferably 100 parts by weight of the total of tetracarboxylic dianhydride and diamine used when synthesizing the polyamic acid. 5 parts by weight or less.

[Solution viscosity of imidized polymer]
The imidized polymer contained in the liquid crystal aligning agent of the present invention preferably has a solution viscosity of 20 to 800 mPa · s, preferably 30 to 500 mPa · s, when this is a 10% by weight solution. It is more preferable. The solution viscosity (mPa · s) of the imidized polymer was measured at 25 ° C. using an E-type viscometer for a polymer solution having a concentration of 10% by weight prepared using a good solvent for the imidized polymer. It is the value.

<Other ingredients>
The vertically aligned liquid crystal alignment film of the present invention contains the imidized polymer as described above as an essential component, but may contain other components as necessary. Examples of such other components include polyamic acid, a compound having at least one, preferably two or more epoxy groups in the molecule (hereinafter referred to as “epoxy compound”), a functional silane compound, and the like. it can.
[Polyamic acid]
The polyamic acid can be obtained by reacting tetracarboxylic dianhydride and diamine.
Examples of the tetracarboxylic dianhydride used for synthesizing the polyamic acid include the same ones as exemplified above as the tetracarboxylic dianhydride used for obtaining the imidized polymer. . Of these, 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, 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-dio So-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, bicyclo [2.2.2] -oct-7-ene-2,3,5,6-tetracarboxylic acid Anhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxo Tetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxynorbornane-2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenone Tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenylsulfur Tetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, the above formula (T-5) ˜ At least one selected from the group consisting of a compound represented by each of (T-7) and a compound represented by the above formula (T-8) (hereinafter referred to as “specific tetracarboxylic dianhydride (2)”) .) Is preferable from the viewpoint that the formed liquid crystal alignment film can exhibit better liquid crystal alignment.

  The tetracarboxylic dianhydride used to synthesize the polyamic acid contains 70 mol% or more of the specific tetracarboxylic dianhydride (2) as described above with respect to the total tetracarboxylic dianhydride. It is preferable that 80 mol% or more is contained, and 90 mol% or more is particularly preferable.

Examples of the diamine used for synthesizing the polyamic acid include the same ones exemplified above as the diamine used for obtaining the imidized polymer.
Among these, the diamine used for synthesizing the polyamic acid includes at least one selected from the group consisting of the compounds exemplified above as other diamines (hereinafter referred to as “specific diamine”). Preferably, the specific diamine is more preferably contained in an amount of 10 mol% or more, more preferably 30 mol% or more, and particularly preferably 50 mol% or more with respect to the total diamine.
The synthesis of the polyamic acid can be performed in the same manner as the synthesis of the polyamic acid as an intermediate product for synthesizing the imidized polymer as an essential component of the liquid crystal aligning agent of the present invention.
The reaction solution obtained by dissolving the polyamic acid thus obtained may be used for the preparation of the liquid crystal aligning agent as it is, and after the polyamic acid contained in the reaction solution is isolated, it is used for the preparation of the liquid crystal aligning agent. Alternatively, the isolated polyamic acid may be purified and then used for the preparation of the liquid crystal aligning agent. Isolation and purification of the polyamic acid can be carried out in the same manner as in the isolation and purification of the polyamic acid which is an intermediate product of the imidized polymer, respectively.
When the liquid crystal aligning agent of the present invention contains a polyamic acid, the use ratio is an imide with respect to the total number of amic acid structures possessed by the polyamic acid and the number of amic acid structures possessed by the imidized polymer and the number of imide ring structures. The ratio of the number of imide ring structures of the polymerized polymer (hereinafter referred to as “average imidization ratio”) is preferably 10 to 50%. The average imidation ratio is more preferably 10 to 40%.
The liquid crystal aligning agent of the present invention preferably contains a polyamic acid together with the imidized polymer. Further, by setting the average imidization ratio in the above range, a liquid crystal having good liquid crystal alignment performance and image sticking characteristics. An alignment film can be provided, and the advantage of exhibiting a high degree of coating property can be obtained.

[Epoxy compound]
The said epoxy compound can be contained in the liquid crystal aligning agent of this invention from a viewpoint of improving the adhesiveness with respect to the substrate surface of the liquid crystal aligning film formed.
Examples of such epoxy compounds include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, and 1,6-hexane. Diol 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′-tetraglycidyl-4,4′-dia Bruno diphenylmethane, N, N-diglycidyl - benzylamine, N, N-diglycidyl - aminomethyl cyclohexane, etc., it may be mentioned as being preferred. The use ratio of these epoxy compounds is the total of the polymers (the total of the imidized polymer and polyamic acid contained in the liquid crystal aligning agent of the present invention. The liquid crystal aligning agent of the present invention is an imidized polymer as a polymer. In the case of containing only the union, it means the amount of the imidized polymer. The same shall apply hereinafter.) The amount is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight with respect to 100 parts by weight. .

[Functional silane compounds]
Examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl)- 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4 7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N- Benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis ( Examples thereof include oxyethylene) -3-aminopropyltrimethoxysilane and N-bis (oxyethylene) -3-aminopropyltriethoxysilane.
The blending ratio of these functional silane compounds is preferably 2 parts by weight or less, more preferably 0.2 parts by weight or less, with respect to 100 parts by weight of the total polymer.

<Liquid crystal aligning agent>
The liquid crystal aligning agent of the present invention is constituted by dissolving the imidized polymer as described above and other components optionally added, preferably in an organic solvent.
As an organic solvent which can be used for the liquid crystal aligning agent of this invention, the solvent illustrated above as what is used for the synthesis | combination reaction of polyamic acid (intermediate product of an imidation polymer) can be mentioned. At this time, the poor solvent illustrated as what can be used together in the synthesis reaction of a polyamic acid can also be selected suitably, and can be used together.
Preferable organic solvents that can be used in the liquid crystal aligning agent of the present invention include, for example, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4 -Hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n -Propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene Examples include glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, isoamyl propionate, isoamyl isobutyrate, and diisopentyl ether. These can be used alone or in admixture of two or more.

A particularly preferable organic solvent is a mixed solvent obtained by combining the above-mentioned organic solvents, each component does not precipitate in the liquid crystal aligning agent, and the surface tension of the liquid crystal aligning agent is in the range of 25 to 40 mN / m. It is such a composition.
The solid content concentration in the liquid crystal aligning agent of the present invention (the ratio of the total weight of components other than the organic solvent in the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is selected in consideration of viscosity, volatility, etc. However, it is preferably in the range of 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention is applied to the substrate surface to form a coating film that becomes a liquid crystal alignment film. When the solid content concentration is less than 1% by weight, the coating film thickness is On the other hand, if the solid content concentration exceeds 10% by weight, the film thickness of the coating film becomes excessive and it is difficult to obtain a good liquid crystal alignment film. In addition, the viscosity of the liquid crystal aligning agent may increase, resulting in poor coating characteristics.
The particularly preferable range of the solid content concentration varies depending on the method employed when the liquid crystal aligning agent is applied to the substrate. For example, when coating is performed by a spinner method, the range of 1.5 to 4.5% by weight is particularly preferable. In the case of the printing method, it is particularly preferable that the solid content concentration is in the range of 3 to 9% by weight, and thereby the solution viscosity is in the range of 12 to 50 mPa · s. In the case of the ink jet method, it is particularly preferable that the solid content concentration is in the range of 1 to 5% by weight, and thereby the solution viscosity is in the range of 3 to 15 mPa · s.
The temperature at which the liquid crystal aligning agent of the present invention is prepared is preferably 0 ° C to 100 ° C, more preferably 20 ° C to 60 ° C.

<Liquid crystal display element>
The liquid crystal display element of the present invention comprises a liquid crystal alignment film formed from the liquid crystal aligning agent of the present invention as described above.
The liquid crystal display element of the present invention can be produced, for example, by the following method.
(1) First, the liquid crystal alignment film of the present invention is applied onto a pair of substrates, and the solvent is removed to form a coating film. Here, when the display mode of the liquid crystal display element to be manufactured is a vertical electric field system such as a TN type, an STN type, or a VA type, two substrates on which a transparent conductive film patterned on one side is provided. Are used as a pair of substrates. On the other hand, when the display mode of the liquid crystal display element to be manufactured is a horizontal electric field method, a pair of a substrate provided with a transparent conductive film having a comb-like pattern and a substrate not having a transparent conductive film is used. Used as a substrate.
In any of the above cases, the liquid crystal aligning agent is applied onto the substrate (on the surface having the transparent conductive film of the substrate when the substrate has a transparent conductive film). As the substrate, for example, glass such as float glass or soda glass; a transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, poly (cycloaliphatic olefin) can be used. Examples of the transparent conductive film provided on one surface of the substrate include an NESA film (registered trademark of PPG, USA) made of tin oxide (SnO ₂ ), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ —SnO ₂ ), and the like. Can be used. In addition, in order to obtain these patterned transparent conductive films, a method of forming a pattern by a photo-etching method after forming a transparent conductive film without a pattern, and a mask having a desired pattern when forming the transparent conductive film. For example, a method of directly forming a patterned transparent conductive film can be employed.
The liquid crystal aligning agent can be applied onto the substrate by an appropriate application method such as a roll coater method, a spinner method, a printing method, or an ink jet method. The liquid crystal aligning agent of this invention has the advantage which can exhibit especially favorable applicability | paintability (printability), when an offset printing method is employ | adopted as an application | coating method.
When applying the liquid crystal aligning agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film, a functional silane compound, a functional titanium compound, or the like is applied in advance to the coated surface of the substrate. You may keep it.

After the application, preheating (pre-baking) is preferably performed for the purpose of preventing dripping of the applied alignment agent. The pre-bake temperature is preferably 30 to 200 ° C, more preferably 40 to 150 ° C, and particularly preferably 40 to 100 ° C. The pre-bake time is preferably 10 seconds to 20 minutes, more preferably 10 seconds to 10 minutes. Thereafter, a baking (post-baking) step is performed for the purpose of completely removing the solvent. The purpose of this post-baking is to completely remove the solvent from the coating film, and when the imidized polymer contained in the liquid crystal aligning agent of the present invention has an amic acid structure or the liquid crystal aligning agent of the present invention is used. In the case of containing a polyamic acid or both of them, the dehydration cyclization of the amic acid structure of the polymer contained in the liquid crystal aligning agent of the present invention is further advanced by heating, and the average imidation ratio of the coating film is increased. It can also be carried out for the purpose of raising it. The post-baking temperature is preferably 80 to 300 ° C, more preferably 120 to 250 ° C. The post-bake time is preferably 5 to 60 minutes, more preferably 5 to 30 minutes.
Thus, the coating film used as a liquid crystal aligning film can be formed. The film thickness of the formed coating film is preferably 0.001-1 μm, more preferably 0.005-0.5 μm.
When the liquid crystal display element to which the liquid crystal aligning agent of the present invention is applied is a VA type liquid crystal display element, a projecting building as described in, for example, Patent Document 7 (Japanese Patent Laid-Open No. 2002-327058) is used. After forming on a substrate, a liquid crystal aligning agent may be applied to improve viewing angle characteristics.

(2) When the display mode of the liquid crystal display element to be manufactured is the VA type, the coating film formed as described above can be used as a liquid crystal alignment film as it is. The rubbing process described may be performed. On the other hand, when the display mode of the liquid crystal display element to be manufactured is a vertical electric field method other than the VA type or a horizontal electric field method, a rubbing process is performed on the formed coating film surface.
The rubbing treatment can be performed by a method of rubbing in a certain direction with a roll around which a cloth made of fibers such as nylon, rayon, and cotton is wound. Thereby, the orientation ability of a liquid crystal molecule is provided to a coating film, and it becomes a liquid crystal aligning film. Furthermore, a part of the liquid crystal alignment film as shown in, for example, Patent Document 8 (Japanese Patent Laid-Open No. 6-222366) or Patent Document 9 (Japanese Patent Laid-Open No. 6-281937) is applied to the coating film after the rubbing treatment. Or a part of the surface of the liquid crystal alignment film as disclosed in Patent Document 10 (Japanese Patent Laid-Open No. 5-107544) By forming a resist film on the top and performing a rubbing treatment in a direction different from the previous rubbing treatment, and then removing the resist film so that the liquid crystal alignment film has different liquid crystal alignment capabilities for each region, It is possible to improve the visibility characteristics of the obtained liquid crystal display element.

(3) A liquid crystal cell is manufactured by preparing two substrates on which a liquid crystal alignment film is formed as described above, and disposing a liquid crystal between the two substrates facing each other. Here, when the rubbing process is performed on the coating film, the two substrates are disposed to face each other so that the rubbing directions in the respective coating films are at a predetermined angle, for example, orthogonal or antiparallel.
In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example.
The first method is a conventionally known method. First, two substrates are arranged to face each other through a gap (cell gap) so that the respective liquid crystal alignment films are opposed to each other, and the peripheral portions of the two substrates are bonded using a sealant, and the substrate surface and the sealant are bonded. A liquid crystal cell can be manufactured by injecting and filling liquid crystal into the cell gap partitioned by the step, and then sealing the injection hole.
The second method is a method called an ODF (One Drop Fill) method. For example, an ultraviolet light curable sealing material is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and liquid crystal is dropped on the liquid crystal alignment film surface. The other substrate is bonded so as to face each other, and then the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant, whereby a liquid crystal cell can be manufactured.
Regardless of which method is used, the liquid crystal cell produced as described above is further heated to a temperature at which the liquid crystal used takes an isotropic phase, and then gradually cooled to room temperature, so that the flow alignment during liquid crystal injection is achieved. It is desirable to remove.
And the liquid crystal display element of this invention can be obtained by bonding a polarizing plate on the outer surface of a liquid crystal cell.

Here, as the sealing agent, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as a spacer can be used.
As the liquid crystal, for example, a nematic liquid crystal, a smectic liquid crystal, or the like can be used, and among these, a nematic liquid crystal is preferable. In the case of a VA liquid crystal cell, a nematic liquid crystal having negative dielectric anisotropy is preferable. For example, a dicyanobenzene liquid crystal, a pyridazine liquid crystal, a Schiff base liquid crystal, an azoxy liquid crystal, a biphenyl liquid crystal, or a phenylcyclohexane liquid crystal is used. It is done. In the case of a TN type liquid crystal cell or an STN type liquid crystal cell, a nematic type liquid crystal having positive dielectric anisotropy is preferable. For example, biphenyl type liquid crystal, phenyl cyclohexane type liquid crystal, ester type liquid crystal, terphenyl type liquid crystal, biphenyl cyclohexane type A liquid crystal, a pyrimidine liquid crystal, a dioxane liquid crystal, a bicyclooctane liquid crystal, a cubane liquid crystal, or the like is used. Examples of these liquid crystals include cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonate, and cholesteryl carbonate; chiral agents such as those sold under the trade names C-15 and CB-15 (Merck); p-decyloxybenzylidene Ferroelectric liquid crystals such as -p-amino-2-methylbutyl cinnamate may be further added and used.
As a polarizing plate bonded to the outer surface of the liquid crystal cell, a polarizing film or an H film in which a polarizing film called an “H film” that absorbs iodine while stretching and aligning polyvinyl alcohol is sandwiched between protective films of cellulose acetate The polarizing plate which consists of itself can be mentioned.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
The polymer solution viscosity in the following synthesis examples is a value measured at 25 ° C. using an E-type viscometer for the heavy duty solution pointed out in each synthesis example.
The imidation rate of the imidized polymer was calculated by the following formula from ¹ H-NMR measured at room temperature using tetramethylsilane as a reference substance after the imidized polymer was dried under reduced pressure at room temperature and then dissolved in deuterated dimethyl sulfoxide. Obtained by (1).

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

(In Formula (1), A ¹ is a peak area derived from protons of NH groups appearing in the vicinity of 10 ppm, A ² is a peak area derived from other protons, and α is a precursor of an imidized polymer (polyamic acid). The number ratio of other protons to one proton of NH group in)

<Synthesis of imidized polymer>
Synthesis example 1
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), 29 g of 1,4-bis (4-aminophenoxy) benzene as the diamine 0.10 mol), 80 g (0.75 mol) of p-phenylenediamine, 24 g (0.10 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 3,6-bis (4-amino) 25 g (0.040 mol) of benzoyloxy) cholestane and 1.4 g (0.015 mol) of aniline as monoamine were added to N-methyl-2-pyrrolidone (N Dissolved in P) 990 g, by performing the reaction for 6 hours at 60 ° C., to obtain a solution containing a polyamic acid. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 61 mPa · s.
Next, 2,800 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 400 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with new γ-butyrolactone (by this solvent replacement operation, pyridine and acetic anhydride used in the dehydration ring closure reaction were removed from the system. The same applies hereinafter). About 2,600 g of a solution containing 15% by weight of an imidized polymer (A-1) having an imidation ratio of about 95% was obtained. A small amount of this solution was collected, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 73 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 16.5 mPa · s.

Synthesis example 2
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), 29 g of 1,3-bis (4-aminophenoxy) benzene as diamine ( 0.10 mol), 80 g (0.75 mol) of p-phenylenediamine, 24 g (0.10 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 3,6-bis (4-amino) 25 g (0.040 mol) of benzoyloxy) cholestane and 1.4 g (0.015 mol) of aniline as monoamine were added to N-methyl-2-pyrrolidone (NM P) A solution containing polyamic acid was obtained by dissolving in 990 g and reacting at 60 ° C. for 6 hours. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 55 mPa · s.
Next, 2,800 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 400 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration and cyclization reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,600 g of a solution containing 15% by weight of an imidized polymer (A-2) having an imidization ratio of about 95%. Obtained. A small amount of this solution was collected, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 70 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 15.0 mPa · s.

Synthesis example 3
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), 1,3-bis (3-aminophenoxy) benzene 29 g as diamine ( 0.10 mol), 80 g (0.75 mol) of p-phenylenediamine, 24 g (0.10 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 3,6-bis (4-amino) 25 g (0.040 mol) of benzoyloxy) cholestane and 1.4 g (0.015 mol) of aniline as monoamine were added to N-methyl-2-pyrrolidone (NM P) A solution containing polyamic acid was obtained by dissolving in 990 g and reacting at 60 ° C. for 6 hours. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 40 mPa · s.
Next, 2,800 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 400 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,600 g of a solution containing 15% by weight of an imidized polymer (A-3) having an imidization ratio of about 95%. Obtained. A small amount of this solution was collected, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 68 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 14.0 mPa · s.

Synthesis example 4
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), 36 g of 4,4'-bis (4-aminophenoxy) biphenyl as diamine (0.10 mol), 80 g (0.75 mol) of p-phenylenediamine, 24 g (0.10 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 3,6-bis (4- 25 g (0.040 mol) of aminobenzoyloxy) cholestane and 1.4 g (0.015 mol) of aniline as monoamine were added to N-methyl-2-pyrrolidone ( NMP) was dissolved in 990 g and reacted at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 60 mPa · s.
Next, 2,800 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 400 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,600 g of a solution containing 15% by weight of an imidized polymer (A-4) having an imidization ratio of about 95%. Obtained. A small amount of this solution was collected, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 73 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 16.1 mPa · s.

Synthesis example 5
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), 38 g of bis [4- (4-aminophenoxy) phenyl] ether as diamine (0.10 mol), 80 g (0.75 mol) of p-phenylenediamine, 24 g (0.10 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 3,6-bis (4- 25 g (0.040 mol) of aminobenzoyloxy) cholestane and 1.4 g (0.015 mol) of aniline as monoamine were added to N-methyl-2-pyrrole. It was dissolved in emissions (NMP) 1,000 g, by performing the reaction for 6 hours at 60 ° C., to obtain a solution containing a polyamic acid. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 60 mPa · s.
Next, 2,900 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 400 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,700 g of a solution containing 15% by weight of an imidized polymer (A-5) having an imidization ratio of about 95%. Obtained. A small amount of this solution was collected, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 70 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 16.0 mPa · s.
Synthesis Example 6
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione, 160 g (0.50 mol), 57 g of 1,4-bis (4-aminophenoxy) benzene as the diamine 0.20 mol), 69 g (0.65 mol) of p-phenylenediamine, 24 g (0.10 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 3,6-bis (4-amino) 25 g (0.040 mol) of benzoyloxy) cholestane and 1.4 g (0.015 mol) of aniline as monoamine were added to N-methyl-2-pyrrolidone (N Dissolved in P) 1,000 g, by performing the reaction for 6 hours at 60 ° C., to obtain a solution containing a polyamic acid. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 59 mPa · s.
Next, 3,000 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 400 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with new γ-butyrolactone (by this solvent replacement operation, pyridine and acetic anhydride used in the dehydration ring closure reaction were removed from the system. The same applies hereinafter). About 2,800 g of a solution containing 15% by weight of an imidized polymer (A-6) having an imidization ratio of about 95% was obtained. A small amount of this solution was collected, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 73 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 16.0 mPa · s.

<Synthesis of polyamic acid>
Synthesis example 7
200 g (1.0 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 210 g of 2,2′-dimethyl-4,4′-diaminobiphenyl as diamine (1. 0 mol) is dissolved in 370 g of N-methyl-2-pyrrolidone and 3,300 g of γ-butyrolactone, and reacted at 40 ° C. for 3 hours to obtain a solution containing about 10% by weight of polyamic acid (B-1). , 000 g was obtained. The solution viscosity of this polyamic acid solution was 160 mPa · s.
Synthesis example 8
1,2,3,4-Cyclobutanetetracarboxylic dianhydride 98 g (0.50 mol) and pyromellitic dianhydride 110 g (0.50 mol) as tetracarboxylic dianhydride and 4,4 ′ as diamine -By dissolving 200 g (1.0 mol) of diaminodiphenylmethane in 230 g of N-methyl-2-pyrrolidone and 2100 g of γ-butyrolactone, reacting at 40 ° C. for 3 hours, and then adding 1,350 g of γ-butyrolactone About 4,000 g of a solution containing 10% by weight of polyamic acid (B-2) was obtained. The solution viscosity of this polyamic acid solution was 125 mPa · s.

<Comparative synthesis example of imidized polymer>
Synthesis Example 9
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), p-phenylenediamine 91 g (0.85 mol) as diamine, 1, 25 g (0.10 mol) of 3-bis (3-aminopropyl) tetramethyldisiloxane and 25 g (0.040 mol) of 3,6-bis (4-aminobenzoyloxy) cholestane and 1.4 g of aniline as monoamine (0 .015 mol) is dissolved in 960 g of N-methyl-2-pyrrolidone (NMP) and reacted at 60 ° C. for 6 hours, To obtain a solution containing click acid. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 60 mPa · s.
Next, 2,700 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 410 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 2,500 g of a solution containing 15% by weight of an imidized polymer (A-7) having an imidization ratio of about 95%. Obtained. A small amount of this solution was collected, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 70 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 16.0 mPa · s.

Synthesis Example 10
110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1,3-dione 160 g (0.50 mol), 140 g of 1,4-bis (4-aminophenoxy) benzene as diamine ( 0.50 mol), 38 g (0.35 mol) of p-phenylenediamine, 25 g (0.10 mol) of 1,3-bis (3-aminopropyl) tetramethyldisiloxane and 3,6-bis (4-amino) 25 g (0.040 mol) of benzoyloxy) cholestane and 1.4 g (0.015 mol) of aniline as monoamine were added to N-methyl-2-pyrrolidone (N MP) Dissolved in 1,200 g and reacted at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was collected, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 55 mPa · s.
Next, 3,300 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 400 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system was replaced with new γ-butyrolactone to obtain about 3,100 g of a solution containing 15% by weight of an imidized polymer (A-8) having an imidization ratio of about 93%. Obtained. A small amount of this solution was taken, NMP was added, and the solution viscosity measured as a solution having an imidized polymer concentration of 10% by weight was 65 mPa · s, and the solution was measured as a solution having an imidized polymer concentration of 6.0% by weight. The viscosity was 15.6 mPa · s.

Example 1
<Preparation of liquid crystal aligning agent>
The quantity which converted the solution containing the polyimide (A-1) obtained by the said synthesis example 1 and the solution containing the polyamic acid (B-1) obtained by the said synthesis example 6 into the polymer which each contains is each. (A-1) = 20 parts by weight and (B-1) = 80 parts by weight, where γ-butyrolactone (BL), N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) are mixed. 2 parts by weight of N, N, N ′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane as an epoxy compound was added, and the solvent composition was BL: NMP: BC = 68: 17: 15 (weight ratio) ), A solution having a solid content concentration of 6% by weight. A liquid crystal aligning agent was prepared by filtering this solution using a filter having a pore size of 0.2 μm.
Evaluation was performed as follows using this liquid crystal aligning agent. The evaluation results are shown in Table 1.
<Evaluation of coatability>
On the transparent electrode surface of the glass substrate with a transparent electrode made of an ITO film, the liquid crystal aligning agent prepared above is aligned using an offset printing machine (manufactured by Nissha Printing Co., Ltd., model “Angstromer”). Application was performed under the conditions of a drop amount of 0.1 g / sec and a printing tact time of 90 seconds. The orientation agent-coated substrate was pre-baked at 80 ° C. for 1 minute, and further post-baked at 210 ° C. for 10 minutes to form a coating film having an average film thickness of 60 nm.
The repellency and coating unevenness of this coating film were visually observed, and the case where no coating repellency and coating unevenness were observed was determined as “good”, and the other cases were determined as “bad”.

<Manufacture of liquid crystal cells>
A coating film with an average film thickness of 60 nm was formed on the transparent electrode surface of the glass substrate with a transparent electrode made of an ITO film in the same manner as in the evaluation of the coating property. The coating film was rubbed using a rubbing machine having a roll wrapped with a rayon cloth under the conditions of a roll rotation speed of 400 rpm, a stage moving speed of 3 cm / second, and a hair foot indentation length of 0.4 mm. Next, the substrate having the coating film after the rubbing treatment is subjected to ultrasonic cleaning in ultrapure water for 1 minute and dried in a clean oven at 100 ° C. for 10 minutes to form a liquid crystal alignment film on the transparent electrode surface of the glass substrate. did. This operation was repeated to produce a pair (two) of glass substrates having a liquid crystal alignment film on the transparent electrode surface.
After applying an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 μm to the outer edge of the surface having the liquid crystal alignment film of each of the pair of substrates, the liquid crystal alignment film surfaces face each other and the liquid crystal alignment film of both substrates has The adhesive was cured by overlapping and pressing so that the rubbing direction was perpendicular. Next, after filling nematic liquid crystal (MLC-6221 manufactured by Merck & Co., Inc.) between a pair of substrates from the liquid crystal injection port, the liquid crystal injection port is sealed with an acrylic photo-curing adhesive to produce a liquid crystal cell. did.
<Evaluation of pretilt angle>
About the liquid crystal cell manufactured above, the pretilt angle at room temperature was measured by the Senarmon method. When this value is 3 to 6 °, it can be evaluated that the pretilt angle is good, and in other cases, the pretilt angle is evaluated as poor.
<Evaluation of seizure characteristics>
A DC voltage of 17 V was applied to the liquid crystal cell produced above at 100 ° C. for 20 hours. Thereafter, the voltage application was canceled and the mixture was allowed to stand at room temperature for 15 minutes, and then the accumulated charge amount was measured by the flicker elimination method. When the accumulated charge amount is 500 mV or less, it can be evaluated that the image sticking property is good, and when it exceeds 500 mV, the image sticking property is evaluated as poor.

Examples 2 to 13 and Comparative Examples 1 to 4
Example 1 except that the solution containing the polymer shown in Table 1 was used as the polymer-containing solution in such an amount that the weight converted to the polymer contained would be the value shown in Table 1, respectively. In the same manner as above, liquid crystal aligning agents were prepared and evaluated. The evaluation results are shown in Table 1.

Claims (7)

Tetracarboxylic dianhydride;
1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl The polyamic acid obtained by reacting a diamine containing 3 to 30 mol% of at least one selected from the group consisting of ether and 4,4′-bis (4-aminophenoxy) biphenyl with respect to the total diamine is dehydrated and cyclized. A liquid crystal aligning agent characterized by containing an imidized polymer.   The tetracarboxylic dianhydride is 2,3,5-tricarboxycyclopentylacetic dianhydride and 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5- The liquid crystal aligning agent of Claim 1 which contains at least 1 sort (s) chosen from the group which consists of dioxo-3-furanyl) -naphtho [1,2-c] -furan-1,3-dione. In addition to the above polymers,
The liquid crystal aligning agent of Claim 1 or 2 which further contains the polyamic acid obtained by making tetracarboxylic dianhydride and diamine react.   The number of amic acid structures of polyamic acid contained in the liquid crystal aligning agent and the ratio of the number of amic acid structures of imidized polymer and the number of imide ring structures of imidized polymer to the total number of imide ring structures The liquid crystal aligning agent of Claim 3 whose is 10 to 50%.   The compound which has at least 1 epoxy group in a molecule | numerator is further contained 0.1-30 weight part with respect to a total of 100 weight part of a polyamic acid and an imidation polymer, The any one of Claims 1-4 further containing. Liquid crystal aligning agent as described in.   The liquid crystal aligning film formed from the liquid crystal aligning agent as described in any one of Claims 1-4.   A liquid crystal display element comprising the liquid crystal alignment film according to claim 6.