JPH09194725A - Film-forming agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a film-forming agent containing a polyamic acid produced by reacting a specific tetracarboxylic acid dianhydride with a diamine compound, forming a film having high imidation ratio even by a low-temperature baking and useful e.g. as an agent for forming a liquid crystal orientation film. SOLUTION: This agent contains a polyamic acid produced by reacting (A) a tetracarboxylic acid dianhydride of the formula (R<1> is a tetravalent organic group) with (B) a diamine compound of the formula H2 N-R<2> -NH2 (R<2> is a bivalent organic group containing basic nitrogen atom). A liquid crystal display element having a liquid crystal orientation film formed by using the film-forming agent is preferably a TN or STN liquid crystal display element and is also preferable as an SH-type, a ferroelectric or an antiferroelectric liquid crystal display element, etc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thin film forming agent. More specifically, the present invention relates to a film forming agent which forms a film having a high imidization rate even at low temperature firing and is particularly suitable as a crystal orientation film forming agent.

[0002]

2. Description of the Related Art Conventionally, a nematic liquid crystal having a positive dielectric anisotropy is sandwiched by a substrate with a transparent electrode having a liquid crystal alignment film made of polyimide or the like, and the long axis of liquid crystal molecules is 90 to 270 between the substrates. There is known a liquid crystal display element (TN type or STN type liquid crystal display element) having a TN type or STN type liquid crystal cell that is twisted continuously. The liquid crystal alignment in the TN type or STN type display element is exhibited by a liquid crystal alignment film made of a resin film subjected to an alignment treatment such as a rubbing treatment. Polyimide is preferably used as the resin forming the liquid crystal alignment film. The resin film forming the liquid crystal alignment film made of polyimide, for example, using a solution of polyamic acid as a liquid crystal alignment film forming agent, this is applied to the substrate surface, the coating film is baked, dried, thermal imidization is performed. It is formed by a method of obtaining a resin film. However, if the baking temperature of the liquid crystal alignment film is low, the thermal imidization of the polyamic acid is insufficient, and there is a problem in that the liquid crystal display element may have poor alignment. Further, when the liquid crystal alignment film is treated at a high baking temperature of, for example, 250 ° C. or more in order to sufficiently advance the thermal imidization, there is a problem that the color filter necessary for colorizing the liquid crystal display element is deteriorated.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a film forming agent containing a polyamic acid capable of forming a film having a high imidization ratio even at low temperature firing in order to solve the above-mentioned conventional problems.

[0004]

According to the present invention, the above objects and advantages of the present invention are achieved by the following general formula (1):

[0005]

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A tetracarboxylic acid dianhydride represented by the following formula (wherein R ¹ is a tetravalent organic group) (hereinafter referred to as "compound I") and the following general formula (2) H ₂ N—R ² —NH ₂ (2) (In the formula (2), R ² is a divalent organic group having a basic nitrogen atom) A diamine compound (hereinafter, referred to as “compound II”) It can be achieved by a film forming agent characterized by containing a polyamic acid (hereinafter referred to as “polymer I”) produced by reacting with.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described, by which the purpose, constitution, advantages and effects of the present invention will become apparent.

The film forming agent of the present invention contains polymer I.

<Compound (I)> The compound (I) used for producing the polyamic acid constituting the polymer I is a tetracarboxylic dianhydride, for example, butanetetracarboxylic dianhydride, 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-cyclopentanetetracarboxylic dianhydride, 1,2 , 4,5-Cyclohexanetetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride 3,5,6 -Tricarboxynorbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dianhydride, 5-
(2,5-dioxotetrahydrofural) -3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, bicyclo [2,2,2] -oct-7-ene-2,3,
5,6-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, 1,3,3a, 4,5,9b-hexahydro-7-ethyl-5- (tetrahydro-2,5-dioxo-3- Furanyl) -naphtho [1,2-c] furan-1,3-dione,
1,3,3a, 4,5,9b-hexahydro-8-methyl-
5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione;
1,3,3a, 4,5,9b-hexahydro-8-ethyl-
5- (tetrahydro-2,5-dioxo-3-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- Alicyclic or aliphatic tetracarboxylic dianhydride such as dione;

Pyromellitic dianhydride 3,3 ', 4,4'
-Benzophenone tetracarboxylic acid 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 acid dianhydride, 3,3 ', 4,4'-dimethyldiphenylsilane tetracarboxylic acid dianhydride, 3,3', 4,4'-tetraphenylsilane tetracarboxylic acid Acid dianhydride, 1,2,
3,4-furantetracarboxylic dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenyl sulfide dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenyl sulfone Dianhydride, 4,4'-bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ', 4,4'-perfluoroisopropylidene diphthalic acid dianhydride, 3,3' , 4,4'-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'-diphenylether dianhydride, bis (triphenylphthalic acid) ) -4,4'-Diphenylmethane dianhydride, ethylene glycol-bis (anhydrotrimellitate), propylene glycol-bis (anhydrotrimellitate), 1,4-butanediol-bis (anhydrotrimellitate) ) 1,6-hexanediol-bis (anhydrotrimellitate),
1,8-Octanediol-bis (anhydrotrimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis (anhydrotrimellitate), 3,6-
Mention may be made of aromatic tetracarboxylic dianhydrides such as bis (anhydrotrimellitate) cholestane.

When the film forming agent of the present invention is used as a liquid crystal alignment film forming agent, among 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 acid dianhydride Things, 5- (2,
5-dioxotetrahydrofural) -3-methyl-3-
Cyclohexene-1,2-dicarboxylic dianhydride, bicyclo [2,2,2] -oct-7-ene-2,3,5,6-
Tetracarboxylic acid 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, pyromellitic dianhydride, 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4 '
-Biphenylsulfone tetracarboxylic acid dianhydride and 1,4,5,8-naphthalene tetracarboxylic acid dianhydride are preferable because they exhibit particularly good liquid crystal alignment. The ratio of these preferred tetracarboxylic dianhydrides used is
Usually 20 to 10 based on all tetracarboxylic dianhydrides
0 mol%. These can be used alone or in combination of two or more.

<Compound (II)> The compound (II) used for producing the polymer I is a diamine compound having two amino groups and a basic nitrogen atom other than these amino groups in the molecule, For example, 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-diaminopurine, 5,6
-Diamino-1,3-dimethyluracil, 3,5-diamino-1,2,4-triazole, 6,9-diamino-2-
Ethoxyacridine lactate, 3,8-diamino-6
-Phenylphenanthridine, 1,4-diaminopiperazine, 3,6-diaminoacridine, bis (4-aminophenyl) phenylamine and the like can be mentioned.

When the thin film forming agent of the present invention is used as a liquid crystal alignment film forming agent, among these, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine and 1,4- Bis (3-aminopropyl) piperazine, 1,4-diaminopiperazine and 3,6-diaminoacridine are preferable because they show particularly good liquid crystal alignment. These can be used alone or in combination of two or more.

In the present invention, a part of the compound (II) may be replaced with another diamine compound to the extent that the effects of the present invention are not lost.

Examples of such other diamine compounds include p-phenylenediamine, m-phenylenediamine,
4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 4,
4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, 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, bis [4- (4-aminophenoxy) phenyl] sulfone, 1,4- Bis (4-
Aminophenoxy) benzene, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4,4'-
(M-phenylenediisopropylidene) bisaniline,
1,3-bis (4-aminophenoxy) benzene, 1,3
-Bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 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, 5-amino-1- (4 '
-Aminophenyl) -1,3,3-trimethylindane,
6-amino-1- (4′-aminophenyl) -1,3,3
-Trimethylindane, aromatic diamine such as 2,7-diaminofluorene; Aromatic diamine having hetero atom such as diaminotetraphenylthiophene; 1,1-
Metaxylylenediamine, 1,2-ethylenediamine,
1,3-propanediamine, tetramethylenediamine,
Pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 1,4-diaminocyclohexane,
Isophorone diamine, tetrahydrodicyclopentadienylenediamine, hexahydro-4,7-methanoindanylene methylene diamine, tricyclo [6,2,1,0
2.7] -aliphatic or alicyclic diamine such as undecylenedimethyldiamine, 4,4'-methylenebis (cyclohexylamine);

H ₂ N- (CH ₂ ) _p- (Si (R) ₂ -O) _q -Si (R) _2- (CH ₂ ) _p -NH ₂ (wherein R is a methyl group, an ethyl group, An alkyl group such as a propyl group, a cycloalkyl group such as a cyclohexyl group, or an aryl group such as a phenyl group having 1 to 1 carbon atoms
2 is a hydrocarbon group, p is 1 to 3 and q is an integer of 1 to 20); and diaminoorganosiloxanes represented by the following formulas (3) to (9).

[0017]

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[0018]

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Examples thereof include diamines containing a steroid skeleton represented by Among these, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 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
-Phenylenediisopropylidene) bisaniline, 4,
4 '-(m-phenylenediisopropylidene) bisaniline and diamines represented by the above formulas (3) to (9) are preferable. These can be used alone or in combination of two or more. These diamines may be used as they are, or may be used after being reduced again. The use ratio of these other diamine compounds, with respect to all diamine compounds,
It is usually 0 to 90 mol%.

<Synthesis of Polymer I> The polymer I constituting the film-forming agent comprises a tetracarboxylic dianhydride of the above compound (I) and a diamine compound having a basic nitrogen atom of the above compound (II). It is synthesized by the reaction. The ratio of the total tetracarboxylic dianhydride and the total diamine compound used for the synthesis reaction of the polymer I is such that the acid anhydride group of the tetracarboxylic dianhydride is 0.2 to 2 per 1 equivalent of the amino group. It is preferably an equivalent amount, more preferably 0.3 to 1.2 equivalents.

The tetracarboxylic dianhydride and the diamine compound are 1 to 48 at a reaction temperature of 0 to 100 ° C. in an organic solvent.
It is preferable to react for a time. At this time, a part of the obtained polyamic acid may be imidized depending on the reaction conditions, but as long as it is soluble in a solvent, it can be used as the polyamic acid in the present invention.

The organic solvent is not particularly limited as long as it can dissolve the polyamic acid produced in the reaction. For example, aprotic polar solvent such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide; m-cresol Examples thereof include phenolic solvents such as xylenol, phenol, and halogenated phenols.

It should be noted that poor organic solvents such as alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons are used in combination with the above organic solvent to such an extent that the polymer produced does not precipitate. be able to. Examples of the poor solvent include methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, acetic acid. Ethyl, butyl acetate, 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-n-hexyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl Ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, ethylene glycol methyl ether acetate, ethylene glycol ethyl ether acetate, ethylene glycol -N-propyl ether acetate, ethylene glycol-i-propyl ether acetate, ethylene glycol-n-butyl ether acetate, ethylene glycol-n-hexyl ether acetate, 4-hydroxy-4-methyl-2-pentanone, 2-hydroxy Ethyl propionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxy. Ethyl propionate, methyl 3-ethoxypropionate,
3-methyl-3-methoxybutanol, 3-ethyl-3
-Methoxybutanol, 2-methyl-2-methoxybutanol, 2-ethyl-2-methoxybutanol, 3-methyl-3-ethoxybutanol, 3-ethyl-3-ethoxybutanol, 2-methyl-2-methoxybutanol, 2 -Ethyl-2-ethoxybutanol, tetrahydrofuran, dichloromethane, 1,2-dichloroethane,
1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane,
Octane, benzene, toluene, xylene and the like can be mentioned. These can be used alone or in combination of two or more.

The amount of the organic solvent used is preferably such that the total amount of the tetracarboxylic dianhydride and all the diamine compounds is 0.1 to 30% by weight based on the total amount of the reaction solution.

A terminal-modified heavy polymer prepared by adding an acid anhydride having only one anhydride group or a monoamine compound for the purpose of controlling the molecular weight and improving the coatability on a substrate during the synthesis of Polymer I. Combined I can also be used in the present invention without any problems.

Examples of the acid anhydrides include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, and n-tetradecylsuccinic anhydride. , N-hexadecylsuccinic anhydride, n-octadecylsuccinic anhydride, and the like.

Examples of the above monoamines include 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- Examples thereof include eicosylamine.

<Intrinsic Viscosity of Polymer I> Intrinsic viscosity of polymer I thus obtained [ηinh = ln (t / t ₀ ).
/ C, where C = 0.5 g / dl, t is the flow rate of the polymer solution, and t ₀ is the flow rate of N-methyl-2-pyrrolidone. Measured at 30 ° C. in N-methyl-2-pyrrolidone, and then measured intrinsic viscosity under the same conditions] is usually 0.0
It is 5 to 10 dl / g, preferably 0.05 to 5 dl / g.

<Film Forming Agent> The film forming agent of the present invention is used as a solution prepared by dissolving the polymer I described above in an organic solvent.

Examples of the organic solvent include the aprotic solvents and phenolic solvents that can be used in the production of the polymer I, or these solvents and the alcohols, ketones, esters, ethers and halogenated hydrocarbons. And a mixed solvent with a poor solvent such as hydrocarbons to the extent that the polymer does not precipitate.

The concentration of the polymer I in the solution is usually
It is 0.1 to 20% by weight, preferably 0.5 to 10% by weight.

The film forming agent of the present invention may contain a functional silane-containing compound shown below for the purpose of further improving the adhesion between the polymer I and the substrate.

Examples of the functional silane-containing compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane and N- (2- Aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-
Aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, 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- Examples thereof include aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane and N-bis (oxyethylene) -3-aminopropyltriethoxysilane.

<Production of Liquid Crystal Display Element> When the film forming agent of the present invention is used as a liquid crystal alignment film forming agent, the liquid crystal display element can be produced by the following method, for example.

(1) A thin film forming agent is applied to the transparent conductive film side of a substrate provided with a patterned transparent conductive film by a roll coater method, a spinner method, a printing method or the like,
The coating is formed by heating at a temperature of 250 ° C, preferably 120-200 ° C. The thickness of this coating is usually 0.00
It is 1 to 1 μm, preferably 0.005 to 0.5 μm.

As the above-mentioned substrate, for example, glass such as float glass and soda glass; transparent substrates made of plastic films such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone and polycarbonate can be used. Further, as the transparent conductive film provided on one surface of the substrate, tin oxide (Sn
O ₂ ) NESA film (registered trademark of PPG Company, USA),
An ITO film made of indium oxide-tin oxide (In ₂ O ₃ —SnO ₂ ) can be used, and a photo-etching method or a method using a mask in advance is used for patterning these transparent conductive films. In applying the liquid crystal aligning agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the liquid crystal aligning agent film, a functional silane-containing compound, a functional titanium-containing compound, etc. Can be applied in advance.

(2) The formed film has a rubbing treatment in which a cloth made of a synthetic fiber such as nylon or rayon is rubbed in a certain direction with a roll, or a polarized ultraviolet ray irradiation is performed to improve the alignment ability of liquid crystal molecules. It is applied to the film to form a liquid crystal alignment film. In addition, uniaxial stretching method, Langmuir
The liquid crystal alignment film can also be formed by a method of obtaining a film by a blow jet method or the like.

Further, the formed liquid crystal alignment film may be applied to, for example, JP-A-6-222366 and JP-A-6-281937.
As described in JP-A-5-107544, or a resist on the surface of a liquid crystal alignment film subjected to a rubbing treatment as disclosed in JP-A-5-107544. By partially forming the film and performing a rubbing treatment in a direction different from the previous rubbing treatment, the resist film is removed and a treatment for changing the alignment ability of the liquid crystal alignment film is performed. It is possible to improve the visibility characteristics.

(3) Two substrates having the liquid crystal alignment film formed as described above are prepared, and the two substrates are separated by a gap (cell gap) so that the alignment treatment directions in the respective liquid crystal alignment films are orthogonal or antiparallel. ), The peripheral portion of the substrate is sealed with a sealant, liquid crystal is filled, and the filling hole is sealed to form a liquid crystal cell. A liquid crystal display device is obtained by laminating a polarizing plate on the outer surface of the liquid crystal cell such that the polarization direction is the same as or orthogonal to the alignment treatment direction of the liquid crystal alignment film on the substrate.

As the sealant, for example, a curing agent and an epoxy resin containing aluminum oxide spheres as a spacer can be used. Examples of the liquid crystal include a nematic liquid crystal and a smectic liquid crystal. Among them, a liquid crystal that forms a nematic liquid crystal is preferable.
Azoxy liquid crystal, biphenyl liquid crystal, phenylcyclohexane liquid crystal, ester liquid crystal, terphenyl liquid crystal,
Biphenylcyclohexane liquid crystal, pyrimidine liquid crystal,
Dioxane-based liquid crystals, bicyclooctane-based liquid crystals, cubane-based liquid crystals, and the like are used. In addition to these liquid crystals, for example, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonaate, and cholesteryl carbonate, and chiral agents such as those sold under the trade names C-15 and CB-15 (Merck Ltd.) are added. It can also be used. Furthermore, p-decyloxybenzylidene-p-
Ferroelectric liquid crystals such as amino-2-methylbutyl cinnamate can also be used.

The polarizing plate used on the outer surface of the liquid crystal cell is a polarizing plate in which a polarizing film called an H film absorbing iodine while sandwiching and aligning polyvinyl alcohol is sandwiched between cellulose acetate protective films, or an H film. Examples thereof include a polarizing plate made of itself.

[0042]

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 liquid crystal alignment of each liquid crystal display element and the imidization ratio of the polymer I were evaluated for each liquid crystal display element produced in the following examples and comparative examples.
The evaluation method is as follows.

[Liquid Crystal Alignment of Liquid Crystal Display Element] The presence or absence of an abnormal domain in the liquid crystal display element when a voltage was turned on and off was observed with a polarizing microscope, and when there was no abnormal domain, it was judged as good. .

[Imidization Ratio of Polymer I] Polymer I
A silicon wafer coated with a thickness of 00A is
Baking is carried out at ℃, 170 ℃, 350 ℃ each for 1 hour. F
The ratio of the absorption of the imide C—N group and the absorption of the imide carbonyl group of polymer I was measured using T-IR. The imidization rate at 100 ° C. was defined as 0% and the imidization rate at 350 ° C. was defined as 100%, and the imidization rate at 170 ° C. was calculated.

Synthesis Example 1 21.81 g (0.10 mol) of pyromellitic dianhydride,
32.84 g (0.08 mol) of 2,2-bis [4- (4-aminophenoxy) phenyl] propane and 2.6
2.18 g (0.02 mol) of diaminopyridine was dissolved in 500 g of N-methyl-2-pyrrolidone and reacted at room temperature for 6 hours. The reaction mixture was then poured into a large excess of methanol, causing the reaction product to precipitate. Then, it was washed with methanol and dried under reduced pressure at 40 ° C. for 15 hours to obtain 52.28 g of a polymer Ia having an intrinsic viscosity of 1.61 dl / g.

Synthesis Example 2 In Synthesis Example 1, the diamine compound was replaced with 2,2-bis [4
-(4-Aminophenoxy) phenyl] propane 20.
Polymer Ib 43. having an intrinsic viscosity of 1.34 dl / g was prepared in the same manner as in Synthesis Example 1 except that 53 g (0.05 mol) and 2,6-diaminopyridine of 5.46 g (0.05 mol) were used.
98 g were obtained.

Synthetic Example 3 In the same manner as in Synthetic Example 1, except that the diamine compound was changed to 10.91 g (0.10 mol) of 2,6-diaminopyridine, an intrinsic viscosity of 1.07 dl / g was obtained. 29.78 g of polymer Ic was obtained.

Synthesis Example 4 Synthesis Example 4 except that the diamine compound was changed to 8.65 g (0.08 mol) of p-phenylenediamine and 2.18 g (0.02 mol) of 2,6-diaminopyridine. In the same manner as in 1 above, 30.02 g of a polymer Id having an intrinsic viscosity of 1.71 dl / g was obtained.

Synthesis Example 5 Except that in Synthesis Example 1, the diamine compound was replaced by 15.86 g (0.08 mol) of 4,4'-diaminodiphenylmethane and 2.18 g (0.02 mol) of 2,6-diaminopyridine. , An intrinsic viscosity of 1.41 in the same manner as in Synthesis Example 1.
36.26 g of polymer Ie with dl / g was obtained.

Synthesis Example 6 In Synthesis Example 1, the diamine compound was replaced with 2,2-bis [4].
-(4-Aminophenoxy) phenyl] propane 14.
37 g (0.035 mol), 4,4'-diaminodiphenylmethane 6.94 g (0.035 mol), a compound of the formula (7) 6.43 g (0.01 mol) and 2,6-diaminopyridine Intrinsic viscosity was 1.41 dl / g in the same manner as in Synthesis Example 1 except that 2.18 g (0.02 mol) was used.
47.59 g of a polymer If was obtained.

Synthesis Example 7 In Synthesis Example 1, the diamine compound was replaced with 2,2-bis [4].
-(4-Aminophenoxy) phenyl] propane 14.
37 g (0.035 mol), 4,4'-diaminodiphenylmethane 6.94 g (0.035 mol), a compound of the formula (7) 6.43 g (0.01 mol) and 2,4-diaminopyrimidine Intrinsic viscosity 1.39 dl / g in the same manner as in Synthesis Example 1 except that 2.20 g (0.02 mol) was used.
47.58 g of a polymer Ig of

Synthesis Example 8 In Synthesis Example 1, the diamine compound was replaced with 2,2-bis [4].
-(4-Aminophenoxy) phenyl] propane 14.
37 g (0.035 mol), 4,4'-diaminodiphenylmethane 6.94 g (0.035 mol), a compound of the formula (7) 6.43 g (0.01 mol) and 1,4-bis ( 3-aminopropyl) piperazine 4.07 g (0.0
(2 mol), except that in the same manner as in Synthesis Example 1, 47.70 g of a polymer Ih having an intrinsic viscosity of 1.21 dl / g was obtained.

Synthesis Example 9 In Synthesis Example 1, the diamine compound was replaced with 2,2-bis [4].
-(4-Aminophenoxy) phenyl] propane 14.
37 g (0.035 mol), 4,4'-diaminodiphenylmethane 6.94 g (0.035 mol), a compound of the formula (7) 6.43 g (0.01 mol) and 1,4-diaminopiperazine Intrinsic viscosity was 1.32 dl / g in the same manner as in Synthesis Example 1 except that the amount was 2.32 g (0.02 mol).
47.49 g of a polymer Ii of

Synthesis Example 10 In Synthesis Example 1, the diamine compound was replaced with 2,2-bis [4]
-(4-Aminophenoxy) phenyl] propane 14.
37 g (0.035 mol), 4,4'-diaminodiphenylmethane 6.94 g (0.035 mol), a compound of the formula (7) 6.43 g (0.01 mol) and 3,6-diaminoacridine Intrinsic viscosity was 1.44 dl / g in the same manner as in Synthesis Example 1 except that 4.19 g (0.02 mol) was used.
48.59 g of a polymer Ij of

Synthesis Example 11 In Synthesis Example 6, tetracarboxylic acid dianhydride was added to 1,3
-Dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride 22.42 g (0.10 mol) except that the intrinsic viscosity was 1.21 dl / g in the same manner as in Synthesis Example 6.
47.69 g of a polymer Ik of

Synthesis Example 12 In Synthesis Example 6, tetracarboxylic acid dianhydride was added to 3,
3 ', 4,4'-biphenyltetracarboxylic dianhydride 2
A polymer Il54. Having an intrinsic viscosity of 1.49 dl / g was prepared in the same manner as in Synthesis Example 6 except that the amount was 9.22 g (0.10 mol).
69 g were obtained.

Synthesis Example 13 In Synthesis Example 6, tetracarboxylic dianhydride was added to 1,3,
3a, 4,5,9b-hexahydro-8-methyl-5-
(Tetrahydro-2,5-dioxo-3-furanyl)-
Naft [1,2-c] furan-1,3-dione 31.43
55.32 g of a polymer Im having an intrinsic viscosity of 1.49 dl / g in the same manner as in Synthesis Example 6 except that the amount was changed to g (0.10 mol).
I got

Synthesis Example 14 In Synthesis Example 6, tetracarboxylic dianhydride was added to 2,3,
5-tricarboxycyclopentyl acetic acid dianhydride 22.
A polymer In45.3 having an intrinsic viscosity of 1.49 dl / g was prepared in the same manner as in Synthesis Example 6 except that the amount was 42 g (0.10 mol).
0 g was obtained.

Synthesis Example 15 (Comparative Synthesis Example) In Synthesis Example 1, the diamine compound was replaced with 2,2-bis [4].
-(4-Aminophenoxy) phenyl] propane 41.
Polymer Io 58.6 having an intrinsic viscosity of 1.69 dl / g was prepared in the same manner as in Synthesis Example 1 except that the amount was changed to 06 g (0.10 mol).
5 g were obtained.

Example 1 5 g of the polymer Ia obtained in Synthesis Example 1 was mixed with N-methyl-2.
-Pyrrolidone was dissolved to obtain a solution having a solid content concentration of 4% by weight, and the solution was filtered through a filter having a pore size of 1 µm to prepare a film forming agent. This film forming agent was applied to the transparent electrode surface on a glass substrate with a transparent electrode made of an ITO film by using a printing machine for applying a liquid crystal alignment film, dried at 170 ° C. for 1 hour and baked to give a dry film thickness of 0. A film having a thickness of 0.05 μm was formed.
With a rubbing machine having a roll in which a rayon cloth is wrapped around this coating, the rotation speed of the roll is 500 rp.
m, the moving speed of the stage was 1 cm / sec, and the length of pushing in the hair was 0.4 mm.

Next, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 17 μm was applied by screen printing to the outer edges of the pair of rubbing-treated substrates having the liquid crystal alignment film, and then the pair of substrates was placed on the liquid crystal alignment film surface. And the orientation treatment direction, that is, the rubbing direction are orthogonal to each other, and the layers are pressure-bonded to cure the adhesive. Next, after filling a nematic liquid crystal (MLC-6419, manufactured by Merck & Co., Inc.) between the pair of substrates through the liquid crystal inlet, the liquid crystal inlet is sealed with an epoxy adhesive, and a polarizing plate is provided on both sides of the substrate. Were laminated so that the polarization direction of the polarizing plate coincided with the rubbing direction of the liquid crystal alignment film of each substrate to produce a liquid crystal display element, and the alignment of the liquid crystal was good. Further, the imidation ratio of this coating was measured and it was a high value of 76%. Table 1 shows the results.

Examples 2 to 14 Polymer I obtained in Synthesis Example 2 to 14 in Example 1
A liquid crystal cell was prepared in the same manner as in Example 1 except that the film forming agent was prepared using. The liquid crystal orientation and imidization ratio were evaluated, and the results are shown in Table 1.

Comparative Example 1 A liquid crystal cell was prepared in the same manner as in Example 1 except that the polymer Io obtained in Synthesis Example 15 was used to prepare a film forming agent. The liquid crystal orientation and imidization ratio were evaluated, and the results are shown in Table 1.

[0064]

[Table 1]

[0065]

According to the film forming agent of the present invention, a thin film having a high imidization rate can be formed even at low temperature firing, and it can be particularly preferably used as a liquid crystal alignment film forming agent. The liquid crystal display device having a liquid crystal alignment film formed by using the film forming agent of the present invention can be suitably used for a TN type or STN type liquid crystal display device, and by selecting a liquid crystal to be used, S
It can also be suitably used for H (Super Homeotropic) type, ferroelectric and antiferroelectric liquid crystal display devices and the like. Furthermore, a liquid crystal display device having a liquid crystal alignment film formed by using the film forming agent of the present invention can be effectively used in various devices, for example, desktop calculators, wrist watches, table clocks, coefficient display plates, word processors, personal computers, liquid crystals. Used for display devices such as televisions. The film forming agent of the present invention can be suitably used not only as a liquid crystal alignment film forming agent, but also as a protective film for electronic materials, various coating materials for building materials, offices and the like.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yasuaki Rokka 2--11-24 Tsukiji, Chuo-ku, Tokyo Inside Nippon Gosei Rubber Co., Ltd. (72) Inventor Yasuo Matsuki 2--11 Tsukiji, Chuo-ku, Tokyo No. 24 Nippon Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. The following general formula (1): (In formula (1), R ¹ is a tetravalent organic group) and a tetracarboxylic dianhydride represented by the following general formula (2) H ₂ N—R ² —NH ₂ (2) (formula ( In 2), R ² contains a polyamic acid produced by reacting with a diamine compound represented by the formula (2), which is a divalent organic group having a basic nitrogen atom).