JPH07120769A - Liquid crystal orienting agent - Google Patents

Abstract

PURPOSE:To obtain a liquid crystal oriented film which is hardly scratched during rubbing by using an liquid crystal orienting agent containing a diazide compd. and a polymer material and/or its imidized polymer obtd. by the reaction of a tetracarboxylic acid dianhydride and a diamine compd. CONSTITUTION:This orienting agent contains the components (a) and (b). (a) A polymer material (specified polymer I) and/or its imidized polymer (specified polymer II) obtd. by the reaction of a tetracarboxylic acid dianhydride (compd. I) and a diamine compd. (comd. II). (b) Diazide compd. As for the compd. I, for example, butane tetracarboxylic acid dianhydride and 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride are used. As for the compd. II, for example, p-phenylene diamine and m-phenylenediamine are used. The proportion of the diazide compd. used to 100 pts.wt. of the specified polymer I and/or specified polymer II is 0.1-20 pts.wt.

Description

Detailed Description of the Invention

The present invention relates to a liquid crystal aligning agent. More specifically, the present invention relates to a liquid crystal aligning agent that can obtain a liquid crystal aligning film that is not easily scratched during rubbing.

[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, STN type display element) having a TN, STN type liquid crystal cell which is continuously twisted. This T
The liquid crystal orientation in the N, STN type display element is formed by a rubbing-treated liquid crystal orientation film, but there is a problem that the liquid crystal orientation film is damaged due to friction during rubbing and affects display characteristics. is doing.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal aligning agent capable of obtaining a liquid crystal aligning film which is less likely to be scratched during rubbing in order to solve the above conventional problems.

[0004]

[Means for Solving the Problems] As a result of extensive studies on the above problems, a polymer obtained by reacting a tetracarboxylic acid dianhydride and a diamine compound and / or its imidized polymer, and a diazide compound are identified. It was found that by using the contained liquid crystal aligning agent, a liquid crystal aligning film that is not easily scratched during rubbing can be obtained.

According to the present invention, the above objects and advantages of the present invention can be achieved by a liquid crystal aligning agent characterized by containing the following components (a) and (b). (A) a polymer (hereinafter referred to as "specific polymer I") obtained by reacting a tetracarboxylic dianhydride (hereinafter referred to as "compound I") and a diamine compound (hereinafter referred to as "compound II") and / or The imidized polymer (hereinafter referred to as "specific polymer II"). (B) A diazide compound (hereinafter referred to as "compound III").

Examples of the compound I used in the present invention include butanetetracarboxylic dianhydride, 1,2,
3,4-cyclobutanetetracarboxylic dianhydride, 1,
2,3,4-Cyclopentanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, tetracyclo [6,2,1,1,0 ^2,7 ] dodecane-4,5,5 9,10-tetracarboxylic dianhydride,
3,5,6-Tricarboxynorbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofuran 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, 5- (2,5-dioxotetrahydrofuranyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid dianhydride, bicyclo [2,2,2] -oct-
Aliphatic and alicyclic tetracarboxylic dianhydrides such as 7-ene-2,3,5,6-tetracarboxylic dianhydride; pyromellitic dianhydride, 3,3 ', 4,4'- Benzophenone tetracarboxylic dianhydride, 3,3 ', 4,4'
-Biphenyl sulfone tetracarboxylic acid dianhydride, 1,
4,5,8-naphthalenetetracarboxylic dianhydride,
2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenylethertetracarboxylic dianhydride, 3,3', 4,4'-dimethyldiphenylsilanetetracarboxylic Acid 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-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ′,
4,4'-perfluoroisopropylidene diphthalic 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 and other aromatic tetracarboxylic dianhydrides. Among these, butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, tetracyclo [6,2,1,
1,0 ^2,7 ] Dodecane-4,5,9,10-tetracarboxylic dianhydride, 5- (2,5-dioxotetrahydrofural) -3-methyl-3-cyclohexene-1,2-
Dicarboxylic acid dianhydride, 1,3,3a, 4,5,9b-
Hexahydro-5-tetrahydro-2,5-dioxo-
3-furanyl) -naphtho [1,2-c] -furan-1,
3-dione, pyromellitic dianhydride, 3,3 ′, 4
4'-benzophenone tetracarboxylic dianhydride, 3,
3 ', 4,4'-biphenylsulfone tetracarboxylic acid dianhydride, 3,3', 4,4'-perfluoroisopropylidene diphthalic acid dianhydride, 3,3 ', 4,4'-
Biphenyltetracarboxylic dianhydride is preferred.

Examples of the compound II used in the present invention 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-phenylenediisopropyl) Redden)
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 Aromatic diamines such as'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl; diaminotetraphenyl Aromatic diamine having a hetero atom such as thiophene; 1,1-metaxylylenediamine, 1,2-ethylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octa Methylenediamine, nonamethylenediamine, 1,4-diaminocyclohexane, isophoronediamine Tetrahydrodicyclopentadiene cyclopentadienylide diamine, hexahydro-4,7
Methanoin danylene dimethylene diamine, tricyclo [6,2,1,0 ^2.7 ] -undecylenedimethyl diamine, 4,4'-methylene bis (cyclohexyl amine)
Aliphatic or alicyclic diamines such as;

[0008]

[Chemical 1]

(In the formula, R represents a hydrocarbon group having 1 to 12 carbon atoms such as an alkyl group such as a methyl group, an ethyl group and a propyl group, a cycloalkyl group such as a cyclohexyl group or an aryl group such as a phenyl group. , P is 1 to 3 and q is an integer of 1 to 20) and the like. Of 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 is preferred.
These can be used alone or in combination of two or more. Further, these diamines may be commercially available products or may be used after re-reduction.

The specific polymer I used in the present invention is obtained by the reaction of compound I and compound II. Such a reaction is generally 0 to 150 ° C., preferably 0 to 10 in an organic solvent.
It is carried out at a temperature of 0 ° C.

The above-mentioned organic solvent used in the reaction includes
Compound I, compound II and specific polymer I formed by the reaction
There is no particular limitation as long as it can dissolve. For example, γ
-Butyrolactone, N-methyl-2-pyrrolidone, N,
Aprotic polar solvents such as N-dimethylformamide, N, N-dimethylacetamide, dimethylsulfoxide, tetramethylurea and hexamethylphosphortriamide; phenolic solvents such as m-cresol, xylenol, phenol and halogenated phenols. be able to. Usually, the amount of the organic solvent used is preferably such that the total amount of compound I and all amine compounds (compound II + monoamine) is 0.1 to 30% by weight based on the total amount of the reaction solution.

The ratio of compound I and diamine compound used is
The acid anhydride group of the tetracarboxylic dianhydride is preferably 0.2 to 2 equivalents, and more preferably 0.3 to 1.4 equivalents, relative to 1 equivalent of the amino group in the diamine compound.

The specific polymer II used in the present invention is obtained by heating or imidizing the specific polymer I described above in the presence of a dehydrating agent and an imidization catalyst. The reaction temperature for imidization by heating is usually 6
It is 0 to 200 ° C, preferably 100 to 170 ° C. If the reaction temperature is less than 60 ° C, the reaction progresses slowly,
If the temperature exceeds ℃, the molecular weight of the soluble polyimide may be significantly reduced. Further, the reaction in the case of imidization in the presence of a dehydrating agent and an imidization catalyst can be carried out in the above-mentioned organic solvent. The reaction temperature is generally 0 to 180 ° C, preferably 60 to 150 ° C. As the dehydrating agent, acid anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used. Further, as the imidization catalyst, for example, tertiary amines such as pyridine, collidine, lutidine, and triethylamine can be used, but the imidization catalyst is not limited thereto. The amount of the dehydrating agent used is 1.6 to 20 with respect to 1 mol of the repeating unit of the specific polymer I.
It is preferably molar. Further, the amount of the imidization catalyst used is preferably 0.5 to 10 mol with respect to 1 mol of the dehydrating agent used.

The intrinsic viscosity of the specific polymer I and / or the specific polymer II thus obtained [η _inh = (ln η
rel / C, C = 0.5 g / dl, 30 ° C., in N-methyl-2-pyrrolidone, the intrinsic viscosity is measured below under the same conditions]
Is usually 0.05 to 10 dl / g, preferably 0.0
It is 5 to 5 dl / g.

The organic solvent may be used in combination to the extent that a poor solvent such as alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbon-forming polymers is not deposited. it can. 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, methyl cellosolve, ethyl cellosolve, ethylene glycol-
n-propyl ether, ethylene glycol-i-propyl ether, butyl cellosolve, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether,
Tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene and the like can be mentioned.

Examples of the compound III used in the present invention include 4,4'-diazidostilbene and 4,4 '.
-Sodium diazidostilbene-2,2'-disulfonate, 1,5-diazidonaphthalene, 1,5-diazidonaphthalene-3,7-disulfonate, 4,
4'-diazidobenzophenone, 4,4'-diazidodiphenylmethane, 4,4'-diazidochalcone, 4,
4'-diazidobenzalacetone, 2,6-di (4-azidobenzal) cyclohexanone, 2,6-di (4-azidobenzal) -4-methylcyclohexanone, 6-azido-2- (4'-azidostyryl) benz Imidazole, 2,6-di (4-azidobenzal) cyclopentanone, 4,4'-diazidobiphenyl, 3,3'-diazidobiphenyl, 4,4'-diazidodiphenylmethane,
3,3'-diazidodiphenylmethane, 4,4'-diazidodiphenylethane, 3,3'-diazidodiphenylethane, 4,4'-diazidodiphenylether, 3,
Diazide compounds such as 3'-diazide diphenyl ether, 4,4'-diazide diphenyl sulfide, 3,3'-diazido diphenyl sulfide, 4,4'-diazide diphenyl sulfone, 3,3'-diazido diphenyl sulfone Can be mentioned. Of these,
2,6-di (4-azidobenzal) cyclohexanone,
2,6-di (4-azidobenzal) -4-methylcyclohexanone is preferred.

The liquid crystal aligning agent of the present invention is prepared by adding compound III to a solution containing specific polymer I and / or specific polymer II.
It is obtained by adding. As the solvent at this time, the above-mentioned solvents can be mentioned.

Specific Polymer I and / or Specific Polymer II
The ratio of compound III to 100 parts by weight is 0.1.
If the proportion of compound III is less than 0.1 part by weight, the effect of preventing rubbing scratches is small, and
If the proportion of compound III exceeds 20 parts by weight, the storage stability of the solution becomes poor.

The liquid crystal aligning agent of the present invention contains the specific polymer I, but monoamine is added at the time of reaction in order to control the molecular weight of these specific polymers and realize the optimum coatability to the substrate. May be.

Examples of the monoamine used in this case 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 -Eicosyl amine etc. can be mentioned.

Further, the liquid crystal aligning agent of the present invention may contain a functional silane-containing compound for the purpose of improving the adhesion between the specific polymer I and the substrate.

Examples of the functional silane-containing compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane and N- (2-amino). Ethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3 -Aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 1
0-trimethoxyisyl-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 (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane and the like can be mentioned.

The liquid crystal display device obtained by using the liquid crystal aligning agent of the present invention can be manufactured, for example, by the following method.

First, the liquid crystal aligning agent of the present invention is applied by printing to the transparent conductive film side of a substrate provided with a transparent conductive film,
The coating film is formed by heating at a temperature of 80 to 200 ° C, preferably 120 to 200 ° C. This coating is usually 0.0
It is from 01 to 1 μm, preferably from 0.005 to 0.5 μm.

The coating film formed as described above is treated as a liquid crystal alignment film by rubbing it with a roll around which a cloth made of synthetic fiber such as nylon is wound.

As the substrate, for example, a transparent substrate made of glass such as float glass or soda glass, plastic film such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone or polycarbonate can be used.

As the transparent conductive film, a NESA film made of SnO ₂ , an ITO film made of In ₂ O ₃ —SnO ₂ or the like can be used. The transparent conductive film is patterned by a photo-etching method, A method using a mask in advance is used.

In applying the liquid crystal aligning agent, in order to further improve the adhesiveness between the substrate and the transparent conductive film and the coating film,
A functional silane-containing compound, titanate or the like can be applied in advance on the substrate and the transparent conductive film.

The substrates having the liquid crystal alignment film formed thereon are made to face each other so that the rubbing directions of the liquid crystal alignment films are orthogonal or antiparallel, and the peripheral portion between the substrates is sealed with a sealant to fill the liquid crystal. Then, the filling hole is sealed to form a liquid crystal cell, and the liquid crystal display element is obtained by laminating the both sides of the liquid crystal cell so that the polarization directions thereof coincide with or are orthogonal to the rubbing direction of the liquid crystal alignment film of the substrate.

As the sealant, for example, a curing agent and an epoxy resin containing aluminum oxide spheres as spacers can be used.

As the above liquid crystal, a nematic type liquid crystal,
Smectic type liquid crystals, among them, those which form nematic type liquid crystals are preferable, for example, Schiff base type liquid crystal, azoxy type liquid crystal, biphenyl type liquid crystal, phenylcyclohexane type liquid crystal, ester type liquid crystal, terphenyl type liquid crystal, biphenylcyclohexane type liquid crystal, pyrimidine type liquid crystal Liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, cubane-based liquid crystals, etc. are used. In addition, these liquid crystals,
For example, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonaate, and cholesteryl carbonate, and trade names C-15 and CB-15 (Merck Lt.
d. It is also possible to add and use a chiral agent such as that sold as). Further, a ferroelectric liquid crystal such as p-decyloxybenzylidene-p-amino-2-methylbutyl cinnamate can also be used.

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

[0033]

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The scratches on the liquid crystal alignment film during rubbing were evaluated by microscopic observation. The orientation of the liquid crystal display device was evaluated by observing the presence or absence of an abnormal domain in the liquid crystal cell when the voltage was turned on and off with a polarizing microscope, and judged that no abnormal domain was found to be good.

Synthetic Example 1 44.8 g of 2,3,5-tricarboxycyclopentylacetic acid dianhydride and 21.6 g of p-phenylenediamine were dissolved in 988 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 to precipitate the reaction product. Then, it was washed with methanol and dried under reduced pressure at 40 ° C. for 15 hours to give a specific polymer Ia60.h having an intrinsic viscosity of 1.44 dl / g.
2 g was obtained.

Synthesis Example 2 30.0 g of the specific polymer Ia obtained in Synthesis Example 1 was added to 570
It was dissolved in g γ-butyrolactone, 21.6 g of pyridine and 16.74 g of acetic anhydride were added, and an imidization reaction was carried out at 120 ° C. for 3 hours. Then, the reaction product solution was precipitated in the same manner as in Synthesis Example 1 to obtain 24.0 g of the specific polymer IIa having an intrinsic viscosity of 1.35 dl / g.

Synthetic Example 3 A specific polymer Ib was obtained in the same manner as in Synthetic Example 1 except that the diamine was changed to 39.6 g of 4,4'-diaminodiphenylmethane.
Was used to carry out an imidization reaction in the same manner as in Synthesis Example 2 to obtain 22.2 g of a specific polymer IIb having an intrinsic viscosity of 1.16 dl / g.
Got

Synthesis Example 4 Intrinsic viscosity 1.26 dl / g in the same manner as in Synthesis Example 1, except that 39.22 g of cyclobutanetetracarboxylic acid dianhydride was used as the tetracarboxylic acid dianhydride.
The specific polymer Ic50.5g was obtained.

Synthesis Example 5 In Synthesis Example 1, tetracarboxylic dianhydride was added to 1,
3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione 60.0 g except that A specific polymer Id was obtained in the same manner as in Synthesis Example 1, and an imidization reaction was performed using this specific polymer Id in the same manner as in Synthesis Example 2 to obtain 22.2 g of a specific polymer IId having an intrinsic viscosity of 1.16 dl / g. Got

Synthesis Example 6 Intrinsic viscosity 1.66 dl / g specific polymer Ie6 in the same manner as in Synthesis Example 1 except that 43.6 g of pyromellitic dianhydride was used as the tetracarboxylic acid dianhydride.
0.5 g was obtained.

Example 1 5 g of the specific polymer Ia obtained in Synthesis Example 1 and 0.5 g (as solid content) of 2,6-di (4-azidobenzal) -4-methylcyclohexanone were dissolved in N-methyl-2-pyrrolidone. A solution having a solid content concentration of 4% by weight was dissolved, and this solution was filtered with a filter having a pore size of 1 μm to prepare a liquid crystal aligning agent solution. This solution was applied on a transparent electrode surface on a glass substrate with a transparent electrode made of an ITO film using a printing machine for applying a liquid crystal alignment film, dried at 200 ° C. for 1 hour, and a dry film thickness of 0.05 μm A film was formed. A rubbing machine having a roll in which a nylon cloth was wound around this coating film was subjected to rubbing treatment at a roll speed of 500 rpm and a stage moving speed of 1 cm / sec.

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 rubbing directions were orthogonal to each other, and they were stacked and pressure-bonded to cure the adhesive. Next, after filling a nematic liquid crystal (ZLI-1565, 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, when the surface of the liquid crystal alignment film was observed with a microscope, almost no rubbing scratches were observed on the surface.

Examples 2 to 9 Examples 2 to 9 were carried out except that a liquid crystal aligning agent was prepared using the specific polymers I and II obtained in Synthesis Examples 2 to 6 and the compound III shown below. A liquid crystal cell was prepared in the same manner as in Example 1. The orientation of the liquid crystal and surface scratches during rubbing were evaluated, and the results are shown in Table 1.

[0043]

[Table 1] A ¹ ; 2,6-di (4-azidobenzal) -4-methylcyclohexanone B ² ; 2,6-di (4-azidobenzal) cyclohexanone

Comparative Example 1 A liquid crystal cell was prepared in the same manner as in Example 1 except that only the specific polymer Ia obtained in Synthesis Example 1 was used. Many rubbing scratches were observed on the surface.

[0045]

According to the liquid crystal aligning agent of the present invention, a liquid crystal aligning film which is not easily scratched during rubbing can be obtained. Further, a liquid crystal display device having a liquid crystal alignment film formed by using the liquid crystal aligning agent of the present invention, SH liquid crystal by selecting the liquid crystal to be used.
(Super Homeotropic), ferroelectric, antiferroelectric liquid crystal display device can also be suitably used. Furthermore, a liquid crystal display device having an alignment film formed by using the liquid crystal aligning agent of the present invention has excellent liquid crystal alignment and reliability, and can be effectively used in various devices. For example, desktop calculators, wrist watches, clocks, and coefficients. It is used for display devices such as display boards, word processors, personal computers, and liquid crystal televisions.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Yusuke Tsuda, 2-11-21 Tsukiji, Chuo-ku, Tokyo Inside Nippon Synthetic Rubber Co., Ltd. (72) Nobuo Bessho 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Nippon Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. A liquid crystal aligning agent comprising 0.1 to 20 parts by weight of the following component (b) with respect to 100 parts by weight of the following component (a). (A) A polymer obtained by reacting a tetracarboxylic acid dianhydride and a diamine compound, and / or an imidized polymer thereof. (B) A diazide compound. [0001]