TW200530376A - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

The present invention provides a excellent liquid crystal display element with high reliability, high liquid crystal alignment property and high rubbing resistance, and a alignment film which could be easily peeled off when substrate reborn. The resolving method of the present invention provides a liquid crystal alignment film made of a polymer or its mixture, which comprises at least one binding unit selected from group consisting of the imide binding unit reacted from tetracarboxylic acid dianhydride and diamine and the amidic acid binding unit. The said tetracarboxylic acid dianhydride comprises at least three which selected from the group consisting of 1, 2, 3, 4-cyclobutane tetracarboxylic acid dianhydride, 3, 3', 4, 4'-dicyclohexyl tetracarboxylic acid dianhydride, 2, 3, 5- tricarboxylic cyclopentyl acetic acid dianhydride, 3, 5, 6-tricarboxylic norbornane-2-acetic acid dianhydride, 2, 3, 4, 5-tetrahydrofuranyl tetracarboxylic acid dianhydride, biscyclo [2. 2. 2]-octa-7diene-2, 3, 5, 6- tetracarboxylic acid dianhydride, 1, 3, 3a, 4, 5, 9b-hexahydro-8-methyl-5-(tetrahydro-2, 5-dioxo-3-furanyl)naphtha[1, 2-c] furan-1, 3-dione and pyromellitic acid dianhydride; and the said diamine comprises at least three which selected from the group consisting of p-phenylene diamine, bis-amino propyl tetramethyl disiloxane. 4, 4-diamino diphenyl methanem, 2, 2-dimethyl-4, 4-diamino biphenyl and 3, 6-bis(4-amino benzoyloxy)cholestane.

Description

200530376 IX. Description of the invention: [Technical field to which the invention belongs] The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element. In more detail, a liquid crystal alignment agent, which can obtain the following liquid crystal alignment film, and the liquid crystal alignment film and the liquid crystal display element using the alignment film, are described. The liquid crystal alignment film has reliability, low afterimage, abrasion resistance, and liquid crystal. It is particularly excellent in alignment, and can be applied to a large substrate. In order to recover the substrate, it can be easily peeled off by any of a commercially available liquid-based or organic-based liquid crystal alignment film peeling solution. [Prior art] In the past, it is known that a TN type liquid crystal display element having a TN (Twisted Nematic) type liquid crystal cell. This TN type liquid crystal display element has a transparent conductive film inserted into two and a liquid crystal is formed on the surface. A nematic liquid crystal layer with positive dielectric anisotropy is formed between the substrates of the alignment film to form a laminated structure. The long axis of the liquid crystal molecules is continuously twisted from one substrate to the other substrate by 90 degrees.

In addition, there are STN (Super Twisted Nematic) type liquid crystal display elements. In the STN type liquid crystal display element, the long axis of the liquid crystal molecules is added between the substrates at 180 degrees or The state of continuous twisting above 180 degrees makes use of the resulting birefringence effect. Furthermore, recently, a nematic liquid crystal layer having a homeotropic alignment state with a negative dielectric anisotropy, or a cholesteric liquid crystal layer having a spiral axis parallel to the substrate normal line has been developed between the opposing substrates. A guest-host reflective liquid crystal display element with a pigment added to the liquid crystal layer. Here, as a liquid crystal alignment film material constituting a liquid crystal display element, it is known to use polyimide, polyimide, polyester, and the like in the past. In particular, polyimide has excellent heat resistance, affinity with liquid crystals, mechanical strength, and the like, and is therefore used in most liquid crystal display elements. However, recently, liquid crystal display elements have gradually developed from high-performance display elements from the aspects of large size, light weight, and low power consumption. Along with this, the required performance of liquid crystal alignment films has become increasingly strict. In particular, the requirements for process improvement and cost reduction associated with the increase in the size of substrates have become stricter. However, in order to achieve high reliability and high alignment quantitative force, an alignment film formed from a polyimide precursor known as polyfluorene imine or a fluorene imine polymer having a structure obtained by dehydrating and closing the ring has been obtained. And high abrasion resistance imparts high adhesion and coating properties to the substrate. As a result, in order to reduce the cost of recycling large substrates, even if the alignment film is peeled off with a commercially available aqueous and organic liquid crystal alignment film peeling liquid, it cannot be peeled off sufficiently. On the other hand, an alignment film that can be easily peeled off using a commercially available liquid crystal alignment film peeling solution has problems of reliability, alignment force, and reduced abrasion resistance. [Summary of the Invention] The object of the present invention is to provide a liquid crystal alignment that can obtain a liquid crystal alignment film that can achieve good reliability, alignment characteristics, abrasion resistance, and can be easily peeled off with commercially available aqueous and organic stripping solutions. Agent. Another object of the present invention is to provide a liquid crystal alignment film having various excellent properties as described above. Still another object of the present invention is to provide a liquid crystal display element having the liquid crystal alignment film of the present invention 200530376 Further objects and advantages of the present invention will be made clear from the following description. According to the present invention, the above-mentioned objects and advantages of the present invention can be achieved by a liquid crystal alignment agent. The liquid crystal alignment agent has a sulfonium imine bond unit and a sulfamic acid formed by the reaction of a tetracarboxylic dianhydride with a diamine. The polymer or a mixture thereof is composed of at least one kind of a bond unit. The polymer or a mixture thereof is characterized in that the tetracarboxylic acid dianhydride contains a compound selected from 1,2,3,4-cyclobutane tetra Carboxylic dianhydride, 3,3,, 4,4, _dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 3,5,6-tricarboxynorbornyl Φ Alkan-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, bicyclic [2 · 2 · 2] -oct-7 · ene-2,3,5,6 · tetracarboxylic acid di Anhydride, 1,3,3 &, 4,5,91) -hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furyl) naphtho [12-c] Furan-1,3 · dione and pyromellitic dianhydride, and the diamine contains at least three selected from p-phenylenediamine, bisaminopropyltetramethyldisilazane, 4,4, _Diaminodiphenylmethane, 2,2'-dimethyl-4,4'-diaminobiphenyl and 3,6-bis (4-amino Benzamidine) at least three of cholestanes. According to the present invention, the above-mentioned objects and advantages of the present invention are secondly achieved by a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention. According to the present invention, the above-mentioned objects and advantages of the present invention are thirdly achieved by a liquid crystal display element having a liquid crystal alignment film of the present invention. Further objects and advantages of the present invention will be apparent from the following description. According to the present invention, a liquid crystal display element having high reliability, high liquid crystal alignment, and high abrasion resistance can be provided, and the alignment film can be easily peeled for recycling the substrate. The liquid crystal display 200530376 display element having a liquid crystal alignment film formed by the liquid crystal alignment agent of the present invention can be applied to TN type and S TN type liquid crystal display elements. By selecting the liquid crystal used, it can also be applied to SH (Super Vertical, Super Homeotropic). ) Type, IPS (ln-piane Switching) type, ferroelectric and antiferroelectric liquid crystal display elements, etc. Furthermore, the liquid crystal display element of the present invention can be effectively used in various devices, such as display devices such as desktop computers, watches, timers, parameter display boards, word processors, personal computers, and liquid crystal televisions. detailed description

Hereinafter, the present invention will be described in detail. The liquid crystal alignment film of the present invention can be generally formed by applying the liquid crystal alignment agent of the present invention to a transparent electrode plate, drying (normally, heating and drying), and performing rubbing or other alignment treatment on the surface of the film. The liquid crystal alignment agent of the present invention is composed of a polymer or a mixture thereof having at least one of a fluorenimine-bonded unit and a fluorinated acid-bonded unit formed by a reaction of a tetracarboxylic dianhydride and a diamine. . When the liquid crystal alignment agent contains both bonding units, it may contain a mixture of polyimide and polyamidic acid, or may contain a polymer having a fluorenimine bonding unit and a fluorene% amine bonding unit. In this polymer, the fluorenimine-bonded unit and the fluorenimine-bonded unit may be contained in either a random state or a block state. In the liquid crystal alignment film of the present invention, during the process of applying the liquid crystal alignment agent to a substrate for drying, the liquid crystal alignment film can be heated and dried to dehydrate and close the fluorene-amine bonding unit of the liquid crystal alignment agent to become the fluorene-imine bonding unit. < Polyamine acid > The polyamino acid used in the present invention can be obtained by addition of ring-opening polymerization of a tetracarboxylic acid dianhydride and a diamine compound. 200530376 [Tetracarboxylic acid anhydride] As the tetracarboxylic acid anhydride, 1,2,3,4-cyclobutanetetracarboxylic acid anhydride, 3,3 ', 4,4'-dicyclohexyltetracarboxylic acid can be used Diacid anhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 3,5,6-tricarboxynorbornane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride , Bicyclo [2.2.2] _oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 1,3,3 &, 4,5,91) -hexahydro-8-methyl- 5- (tetrahydro_2,5-dioxo-3_furanyl) naphtho [1,2-o] furan-1,3-dione and pyromellitic dianhydride.

As the tetracarboxylic dianhydride, it is necessary to use a combination of three or more of the above eight compounds. By using three or more types in combination, the peeling liquid for liquid crystal alignment film can be easily peeled from the substrate as necessary. A combination of three or more kinds preferably contains pyromellitic dianhydride, and especially pyromellitic dianhydride is particularly preferably contained at least 30%. As the polycarboxylic acid anhydride used in the present invention, as a tetracarboxylic acid dianhydride, other tetracarboxylic acid dianhydrides may be contained as necessary in addition to the above-mentioned eight compounds. Examples of the other tetracarboxylic acid dianhydride include butanetetracarboxylic acid dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, and 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-cyclo Hexanetetracarboxylic dianhydride, 1,3,3 &, 4,5,91) -hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1, 2-〇Bufuran-1,3-dione, 1,3,3 &, 4,5,913-hexahydro-5-methyl-5 (tetrahydro-2,5-dioxo-3-furyl) -Naphtho [l, 2-c] -furan_1,3-dione, 1,3,3 &, 4,5,91 > -hexaki-5-ethyl-5 (tetrahydro-2,5 -Dioxo-3-furyl) -naphthalene-10-200530376 benzo [l, 2-c] -furan-1,3-dione, 1,3,3 &, 4,5,91 > -hexahydro -7-methyl-5 (tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2, < bufuran-1,3-dione, 1,3,3 &, 4 , 5,913-hexahydro-7-ethyl-5 (tetrahydro-2,5-dioxo-3-furyl) -naphtho [l, 2-c] -furan-1,3-dione, l , 3 , 3a, 4,5,9b- /, hydrogen-8-ethyl-5 (tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2, <]-furan-1, 3-dione, 1,3,3 &, 4,5,91) -hexahydro-5,8-dimethyl-5 (tetrahydro_2,5-dioxo-3-furyl) -naphthalene [[1,2, c] · furan-1,3 · diketone, 5- (2,5-dioxotetrahydrofurfuryl) -3-methyl-3-cyclohexane-1,2-di Carboxylic acid anhydrides' aliphatic and alicyclic tetracarboxylic acid anhydrides such as compounds represented by the following formulae (1) and (Π);

[Chemical 1]

(In the formula, R1 and R4 represent a divalent organic group having an aromatic ring, R2 and R3 represent a hydrogen atom and an alkyl group, and the plural R2 and R3 may be the same or different, respectively.) 3,3 ', 4,4 '-Benzophenone tetracarboxylic dianhydride, 3,3', 4,4, -biphenylphosphonium tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3 , 6,7-naphthalenetetracarboxylic dianhydride, 3,3 ', 4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3,, 4,4'-dimethyldiphenylsilane Carboxylic acid anhydride, 3,3 ', 4,4'-tetraphenylsilane tetracarboxylic acid di-11- 200530376 • Acid anhydride, 1,2,3,4-furantetracarboxylic acid anhydride, 4,4'- Bis (3,4-dicarboxyphenoxy) diphenylsulfide diacid anhydride, 4,4'_bis (3,4_dicarboxyphenoxy) diphenylsulfide diacid anhydride, 4,4'- Bis (3,4-dicarboxyphenoxy) diphenylpropane dianhydride, 3,3 ', 4,4'-perfluoroisopropylidene diphthalic anhydride, 3,3', 4, 4'-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis (triphenylphthalic acid) dianhydride, m-phenylene-bis (Triphenylphthalate Acid) diacid anhydride, bis (triphenylphthalic acid) -4,4'-diphenylether diacid anhydride, bis (triphenylphthalic acid) -4,4'-diphenylmethanedianhydride , Ethylene φdiol-bis (anhydrotrimellitic acid ester), propylene glycol-bis (anhydrotrimellitic acid ester), 1,4-butanediol-bis (anhydrotrimellitic acid ester), 1,6- Hexanediol-bis (dehydrated trimellitate), 1,8-octanediol-bis (dehydrated trimellitate), 2,2-bis (4-hydroxyphenyl) propane-bis (dehydrated trimellitate) Aromatic tricarboxylic acid anhydride compounds such as a trimellitic acid ester), compounds represented by the following formulae (1) to (4). These can be used individually by 1 type or in combination of at least 2 types.

(1) -12- 200530376

These other tetracarboxylic dianhydrides are preferably 50 to 0.1 mol%, and more preferably 30 to 0.1 mol of the above-mentioned polymer or a mixture thereof used in the present invention with respect to all the tetracarboxylic dianhydrides. %, Particularly preferably used in an amount of 25 to 0.1 mole%. [Diamine compound] As the diamine compound, p-phenylenediamine, bisaminopropyltetramethyl-13-200530376 • dibissiloxane, 4,4'-diaminodiphenylmethane, 2, 2'-dimethyl-4,4, -diaminobiphenyl and 3,6-bis (4-aminobenzyloxy) cholestane. As the diamine, it is necessary to use at least three of these five diamines in combination. By using at least three types in combination, the liquid crystal alignment film can be easily peeled from the substrate with a peeling liquid, if necessary. The polyamidic acid used in the present invention may contain other diamine compounds as a diamine compound in addition to the five compounds described above. Examples of the other diamine compounds include m-phenylenediamine, 4,4'-diamine Φ-based diphenylethane, 4,4, diaminodiphenyl sulfide, and 4,4'-diamine. Diphenyl maple, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzidine aniline, 4,4'-diaminodiphenyl ether , 1,5-Diaminonaphthalene, 3,3'-dimethyl-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-aminobenzene ) Hexafluoropropane, 2,2'-bis [4- (4-aminophenoxy) phenyl] fluorene, 1,4-bis (4-aminophenoxy) benzene, I, 3-bis (4-Aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 2,7- Diaminofluorene, 9,9-bis (4-aminophenyl) fluorene, 4,4'-methylene -Bis (2-chloroaniline), 2,2'-xylylfluoromethyl-4,4'-diaminodiphenyl, 2,2 ', 5,5'-tetrachloro-4,4'- Diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl, 3,3, dimethoxy_4,4'_di Amino benzidine, 1,4,4 '-(p-phenylene isopropylidene) benzidine, 4,4'-(m-phenylene isopropylidene) benzidine, 2,2'-bis [ 4- (4-amino-2-trifluoro-14- 200530376 methylphenoxy) phenyl] hexafluoropropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) Aromatic diamines such as biphenyl, 4,4'-bis [(4-amino-2-trifluoromethyl) phenoxy] -octafluorobiphenyl; p-xylylenediamine, 1,3- Propylene diamine, butanediamine, pentanediamine, hexamethylenediamine, heptanediamine, octanediamine, nonanediamine, heptanediamine, 1,4-diaminocyclohexane, isophoronediamine, Tetrahydrodicyclopentadiene diamine, hexahydro-4,7-methylindene dimethylene diamine, tricyclic [6,2,1,02 · 7] -undecene dimethyl diamine , 4,4'-methylenebis (cyclohexylamine) and other aliphatic and cycloaliphatic diamines;

Mono-substituted phenylene diamines represented by the following formula (III); diamine organosiloxanes represented by the following formula (IV) (except for bisaminopropyltetramethyldisilanes) [化 3]

(III)

(IV) (In the formula, X represents a divalent organic group selected from -0-, -COO-, -OCO-, -NHCO-, -CONH-, and -CO-, and R5 represents a nestol-like skeleton or trifluoro A monovalent organic group of a methyl group. R9 represents a hydrocarbon group having 1 to 12 carbon atoms. The plural R9 may be the same or different. P is an integer of 1 to 3, and q is an integer of 1 to 2005. 200530376 The following formula ( 5) to the compounds represented by (8), etc. These diamine compounds may be used alone or in combination of at least two kinds.

⑹ (wherein y is an integer of 2 to 12, and Z is an integer of 1 to 5) These other diamine compounds are preferably the above-mentioned polymer or a mixture thereof used in the present invention with respect to all the diamine compounds. It is used at 80 to 0.1 mol%, more preferably at 60 to 0.1 mol%, and particularly preferably at 50 to mol.%. -16-200530376 'Use ratio of tetracarboxylic dianhydride and diamine compound for polyamine synthesis reaction, relative to 1 equivalent of amine group contained in diamine compound, acid anhydride group contained in tetracarboxylic dianhydride The ratio is preferably 0.2 to 2 equivalents, and more preferably 0.3 to 1.4 equivalents. In the case where the ratio of the acid anhydride group contained in the tetracarboxylic acid dianhydride is less than 0.2 equivalent and the case where the ratio is more than 2 equivalent, the molecular weight of the obtained polymer becomes too small, and the coating property of the liquid crystal alignment agent is deteriorated. Happening. The polyamidic acid constituting the liquid crystal alignment agent of the present invention is synthesized by reacting the above-mentioned tetracarboxylic acid anhydride and the above-mentioned diamine compound. The synthesis reaction of polyamic acid is generally performed in an organic solvent at a temperature of 0 to 150 ° C, and more preferably at a temperature of 0 to 100 ° C. If the reaction temperature is below o ° C, the solubility of the compound in the solvent may be deteriorated. If it exceeds 150 ° C, the molecular weight of the obtained polymer may be reduced. The organic solvent used in the synthesis of polyamic acid is not particularly limited as long as it can dissolve polycarboxylic acid produced by the reaction of a tetracarboxylic dianhydride and a diamine compound. For example, γ-butyrolactone, N- Methyl-2-pyrrolidone, Ν, Ν-dimethylformamide, Ν, Ν-dimethylacetamide, dimethylarsine, tetramethyl% urea, hexamethylphosphonium triamine, 1, Aprotic polar solvents such as 3-dimethyl-2-imidazolidinone; phenol solvents such as m-cresol, xylenol, phenol, and halogenated phenol. The amount (A) of the organic solvent is preferably such that the total amount (B) of the tetracarboxylic dianhydride and the diamine compound as the reaction raw material is 0 to 30% by weight relative to the total amount of the reaction solution (A + B). The amount. In addition, in the above organic solvent, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons of a weak solvent of polyamino acid can be used in combination within a range in which the generated polyamino acid does not precipitate. Class, etc. As specific examples of the weak solvent, -17-200530376 propane, propane, ketone, butyl alcohol diisoethylethyl di, formic acid alcohol, hexamone, cycloethyl ethyl, methyl butanol, acetone ethyl isopropyl acetate, Ethyl alcohol, ethylene glycol glycol, triethanol, methanol esters, dimethyl T acid, 4-ethylcoe, 1 ,, ,, ketones such as alcohols, dicycloether, ethyl ether monoethylene glycol glycol diethylene glycol Ethyl, diether, methyl ether methyl monomethylene diglycol ethylene glycol, diethyl ether,, ether ester methylglycolate diethylene glycol diether diethylene glycol diethyl ether diethyl ether monomethyl ether Diethylene glycol dimethyl 'alcohol ether dipropylene glycol, diester alkyd diethyl ether, i ether methyl 3 alcohol ethyl di, propyl ester, acid ether ethyl ether ethyl alcohol monodiol propylene diethylene glycol Ethyl ether ether methylol diethylene glycol propylene glycol diethylene glycol dipropyl propyl acid ether ethyl alcohol diethylene propylene glutarate 2-, methyl ether methyl 4-methyl-diyl alcohol lactic acid ethyl lactate, ethyl Ethyl Glycolic Acid, Keto Ester, Ethyl 2-Ethyl Acetate Sour butyrate, methyl ester 4 methyl 3 acid lactate ester propyl 3 oxy methyl ester

Acid propyloxymethyl I alcohol butyloxymethyl 3 I ethyl ethyl, ethyl ester oxy ethyl methyl formate propyl oxyethanol methyl methyl butyl oxy methyl I 2-butyl ethyl I 2 alcohol butyl oxy alcohol butyl oxy ethyl 3 I methyl 3-ethyl-3-ethoxybutanol, 2-methyl-2-ethoxybutanol, 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. They can be used alone or in combination of at least two kinds. By the above synthesis reaction, a polymer solution obtained by dissolving polyamidic acid can be obtained. Then, the reaction solution is poured into a large amount of a weak solvent to obtain a precipitate, and the precipitate is dried under reduced pressure to obtain a polyamic acid. In addition, the polyamic acid can be purified by performing a process of dissolving the polyamic acid once or several times in an organic solvent and then precipitating it in a weak solvent. -18- 200530376 < Polyimine > The polyimide constituting the liquid crystal alignment agent of the present invention can be prepared by the following methods (1) to (2). In addition, a polymer having a so-called fluorene imidization ratio of less than 100% by dehydrating and closing a part of the repeating units of polyamic acid is also suitable for the liquid crystal alignment agent of the present invention. Method (1): A method for heating and dehydrating the polyamidic acid to close the ring. The reaction temperature of this method is preferably 60 to 300 ° C, and more preferably 120 to 250 ° C. The reaction temperature is lower than 60 ° C, and the fluorene imidization reaction cannot proceed sufficiently. When the reaction temperature exceeds 250 ° C, the molecular weight of the resulting polyfluorene imine will decrease. Method (2): A method of dissolving polyamidonic acid in an organic solvent, adding a dehydrating agent and amidine imidization catalyst to the solvent, and heating as required. In this method, as the dehydrating agent, for example, acid anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used. The amount of the dehydrating agent to be used is preferably 1.6 to 20 moles relative to 1 mole of the polyamine repeating unit. In addition, as the hydrazone imidation catalyst, for example, tertiary amines such as pyridine, trimethylpyridine, dimethylpyridine, and triethylamine can be used. However, it is not limited to these. The amount of fluorene imidization catalyst used is preferably 0.5 to 10 moles relative to 1 dehydration agent used. Examples of the organic solvent used in the amidation reaction include the same organic solvents as those exemplified as the solvent used in the synthesis of a polyamic acid. The reaction temperature of the fluorene imidization reaction is preferably 0 to 180 ° C, and more preferably 60 to 150 ° C. < Intrinsic viscosity of polyamidic acid and polyimide > The intrinsic viscosity of polyamidic acid and polyimide obtained as above (3 (rc, measured in N-methyl-2_pyrrolidone. The same applies hereinafter ), Preferably -19- 200530376 0.05 to 10 dl / g, more preferably 0.05 to 5 dl / g. ≪ Terminal-modified polymer> Polyamino acid used in liquid crystal alignment agent forming liquid crystal alignment film of the present invention And polyimide, which can be a terminally modified polymer. The molecular weight of the terminally modified polymer can be adjusted without impairing the effects of the present invention, and the coating characteristics of the liquid crystal alignment agent can be improved. When synthesizing polyamic acid, it is synthesized by adding an acid anhydride, a monoamine compound, or a monoisocyanate compound, etc. to the reaction system. ^ As an acid anhydride added to the reaction system when synthesizing polyamino acid in order to obtain a terminal-modified polymer, Examples include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride, n-hexadecylsuccinic anhydride, etc. In addition, as Examples of the monoamine added to the reaction system include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, Alkylamines such as n-dodecylamine, n-tetradecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n-eicosylamine; 3-aminopropyl Methylmethyldiethoxy sand, 3- [N -anhydropropyl-N- (2-aminoethyl)] trimethylpropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N-[(3-trimethoxysilyl) propyl] diethylenetriamine, etc. Examples of the monoisocyanate compound include isocyanate. Phenyl ester, naphthalate isocyanate, etc. < Liquid crystal alignment agent > The liquid crystal alignment film of the present invention is usually a liquid crystal alignment agent composed of the above-mentioned polyimide and / or polyamic acid dissolved in an organic solvent. -20-200530376 As the organic solvent 5 constituting the liquid crystal alignment agent of the present invention, the same solvents as those exemplified for the solvents used in the polyamine synthesis reaction can be mentioned. In addition, the weak solvent exemplified by the solvent used in combination in the synthesis reaction of polyamic acid can also be appropriately selected and used in combination. The solid content concentration in the liquid crystal alignment agent forming the liquid crystal alignment film of the present invention can be considered in terms of viscosity and volatility. The liquid crystal alignment agent of the present invention is coated on the substrate surface to form a coating film that becomes a liquid crystal alignment film, but the solid content concentration is less than 1% by weight. In the case, the film thickness of the coating film is too small to obtain a good liquid crystal alignment film. When the solid content concentration exceeds 10% by weight, the film thickness of the coating film is too large to obtain a good liquid crystal alignment film. In addition, the liquid crystal alignment The viscosity of the agent increases, and the coating characteristics tend to deteriorate. In addition, the temperature when preparing the liquid crystal alignment agent of the present invention is preferably 0 ° C to 200 ° c, and more preferably 20 ° c to 60 ° c. < Epoxy-containing compound > The liquid crystal alignment agent forming the liquid crystal alignment film of the present invention may optionally include a compound having at least one epoxy group in the molecule. Examples of the compound having at least one epoxy group in the molecule include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol diglycidyl. Glyceryl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2, -dibromo neopentyl glycol diglycidyl ether, 1, 3 ^ Tetraglycidyl-2,4-hexanediol 5 N, N5N, 5N, -tetraglycidyl-m-xylylenediamine 5 1,3-bis (N5N-diglycidylaminomethyl) cyclohexyl Alkane, glycidyl Φ-4; 4 \ diaminodiphenyl parent alkane, etc. as the preferred 5 痄 is the mixing ratio of the epoxy-containing compound 200530376-relative to 100 parts by weight of the polymer, preferably It is not higher than 40 parts by weight, and more preferably 0.1 to 30 parts by weight. The liquid crystal alignment agent forming the liquid crystal alignment film of the present invention may further contain a functional silane-containing compound from the viewpoint of improving the adhesion to the substrate surface. Examples of the functional silane-containing compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, and 2-amino group. Propyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldi , Methoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethyl Oxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethylamine Oxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6- Diazanonylacetate, 9-triethoxysilyl-3,6-diazanonylacetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl 3-Aminopropyltriethoxysilane, N- ^ phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N- double Oxyethylene) -3-aminopropyl trimethoxy Silane, N- bis (oxyethylene) -3-aminopropyl triethoxy silane-like. The mixing ratio of these functional silane-containing compounds is preferably not more than 40 parts by weight, and more preferably 0. 30 parts by weight relative to 100 parts by weight of the polymer. < Liquid crystal display element > A liquid crystal display element obtained using the liquid crystal alignment film of the present invention can be produced by, for example, the following method. -22- 200530376 * (1) Applying a liquid crystal alignment agent for forming a liquid crystal alignment film of the present invention on one side of a substrate provided with a patterned transparent conductive film by a method such as a roll coating method, a rotation method, a printing method, etc., and then, A coating film is formed by heating the coating surface. Here, as the substrate, for example, glass such as float glass and soda glass can be used. The substrate is made of plastics such as polyethylene terephthalate, polybutylene terephthalate, polyether fluorene, and polycarbonate. Transparent substrate. As the transparent conductive film provided on one side of the substrate, a NESA film (registered trademark of the United States PPG Corporation) formed of tin oxide (Sn02), an ITO film formed of indium oxide-tin oxide (In203-Sn02), or the like can be used. The pattern of these transparent conductive films can be a photo-etching method or a pre-mask method. In the application of the liquid crystal alignment agent, in order to improve the adhesion between the substrate surface and the transparent conductive film and the coating film, a functional silane-containing compound, a functional titanium-containing compound, or the like may be coated on the surface of the substrate in advance. The heating temperature after the liquid crystal alignment agent is applied is preferably 80 to 300 ° C, and more preferably 120 to 250 ° C. In addition, the liquid crystal alignment agent of the present invention containing polyamidic acid can be formed into a coating film that becomes an alignment film by removing an organic solvent after coating, and then dehydrating and closing the film by heating. The film thickness of the coating film ^ is preferably 0.001 to 1 μηι, and more preferably 0.005 to 0.5 μηι. (2) The formed coating film surface is subjected to a rubbing treatment in a certain direction by a roller wound with a cloth wound with, for example, nylon, rayon, cotton, or the like. In this way, the liquid crystal alignment film is formed by providing the liquid crystal molecule alignment ability on the coating film. In addition, the liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention can be subjected to a process of changing the pre-tilt angle by locally irradiating ultraviolet rays as shown in Japanese Patent Application Laid-Open No. 6-222366 or Japanese Patent Application Laid-Open No. 6-281937, or 23 · 200530376 * As shown in Japanese Patent Application Laid-Open No. 5- 1 07544, a protective film is locally formed on the surface of the liquid crystal alignment film subjected to rubbing treatment, and the protective film is removed after rubbing treatment in a direction different from the previous rubbing treatment direction. The process of changing the liquid crystal alignment ability of the liquid crystal alignment film can improve the visual field characteristics of the liquid crystal display element. (3) Create two substrates forming a liquid crystal alignment film as described above, and place the two substrates in a gap (cell interval) to face each other. Adhere the surrounding parts of the two substrates with a sealant, and distinguish between the substrate surface and the sealant. The liquid crystal is injected into the cell gap ^, and the injection hole is sealed to form a liquid crystal cell. Furthermore, the outer surface of the liquid crystal cell, that is, the other side of the transparent substrate constituting the liquid crystal cell, was pasted with a polarizing plate to obtain a liquid crystal display element. Here, as the sealant, for example, a curing agent and an epoxy resin containing alumina balls as a gasket can be used. Examples of the liquid crystal include a nematic liquid crystal. For example, Schiff city type liquid crystal, azo oxide type liquid crystal, biphenyl type liquid crystal, phenylcyclohexane type liquid crystal, ester type liquid crystal, bitriphenyl type liquid crystal, biphenylcyclohexane type liquid crystal, and pyrimidine type liquid can be used. ^ Crystalline 'dioxane-based liquid crystal, bicyclooctane-based liquid crystal, cubic alkane-based liquid crystal, etc. In addition, "Cholesterol chloride, cholesterol nonanoate", and cholesterol type liquid crystals such as cholesterol carbonate can be added to these liquid crystals, or those sold under the trade names "C-15" and "CB-15" (manufactured by Merck) can be added. Agents and the like. Examples of the polarizing film adhered to the outer surface of the liquid crystal cell include, for example, a cellulose acetate protective film for polarizing films called a rubidium film that absorbs iodine while orienting polyvinyl alcohol while aligning it, and sandwiching A polarizer or a polarizer formed by the fluorene film itself. -24- 200530376 < Liquid crystal alignment film peeling liquid > Examples of the peeling liquid used for peeling the liquid crystal alignment film of the present invention from a substrate include a glycol-based solvent and a basic compound and / or a nonionic Aqueous surfactant-based stripping solution or organic solvent-based stripping solution containing N-methylpyrrolidone or γ-butyrolactone. Examples of the glycol-based solvent contained in the aqueous solution-based stripping solution include ethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monoisopropyl ether, and diethylene glycol monobutyl ether acetate. Wait.

Examples of the basic compound include lithium hydroxide, sodium hydroxide, potassium hydroxide, sodium hydrogen phosphate, diammonium hydrogen phosphate, dipotassium hydrogen phosphate, disodium hydrogen phosphate, ammonium dihydrogen phosphate, and potassium dihydrogen phosphate. , Sodium dihydrogen phosphate, lithium silicate, sodium silicate, potassium silicate, lithium carbonate, sodium carbonate, potassium carbonate, lithium borate, sodium borate, potassium borate, ammonia, tetramethylammonium hydroxide, dihydroxyethyl hydroxide Trimethylammonium, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, ethanolamine, N-methyl Piperidine, trimethylhydroxyethylammonium hydroxide and the like. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene allyl ether, polyoxyethylene alkyl allyl ether, polyoxyethylene derivatives, and ethylene oxide-propylene oxide block copolymers. Products, sorbitol fatty acid esters, polyoxyethylene sorbitol fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, and the like. In addition, examples of the organic solvent-based stripping solution include those formed from N-methylpyrrolidone or γ-butyrolactone or those containing not less than 20% of the above-mentioned solvent-25-200530376, and 0 to 20% of the above-mentioned basic compound. Peeling fluid, etc. [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 releasability of the liquid crystal alignment films in the examples and comparative examples of this specification was determined by visual observation to determine whether a film was present before and after the coating film on the glass substrate was dipped in the peeling solution. In addition, the abrasion resistance was determined by confirming the presence or absence of scratches after rubbing the coating film formed on the glass substrate 10 times. # Moreover, the alignment and reliability tests of a liquid crystal display element produced using an alignment film were evaluated by the following methods. (Alignment test) A liquid crystal cell was produced on the substrate coated with the alignment film, and the alignment was evaluated by confirming whether a flow alignment was generated when the liquid crystal was vacuum-injected into the cell. (Reliability test) After placing the liquid crystal display element in a 70 ° C thermostatic bath and continuously driving the function waveform generator "Function / arbitrary waveform generator" (manufactured by Hewlett ^ Packard) for 24 hours, the contrast spots and display were confirmed. The presence of defects. Synthesis Example 1 As a tetracarboxylic dianhydride, 224.1 7 g (0.5 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 157.14 g (0.5 mol) of 1,3,3 &, 4,5, 91) -hexahydro-5-methyl · 5- (tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2-(:]-furan-1,3-dione As a diamine compound, 94.62g (0.875 mole) of p-phenylenediamine, 3 2.02g (0.1 mole) of 2,2'-ditrifluoromethyl_4,4, -diaminobiphenyl, -26 -200530376 • 6.43g (0.01 mole) of 3,6-bis (4-aminobenzyloxy) cholestane, 4.04g (0.03 mole) of 4-aminophenyloctadecyl ether dissolved in In 4,500 g of N-methyl-2-pyrrolidone, react at 60 ° C for 6 hours. Then, the reaction solution was poured into a large amount of excess methanol to precipitate the reaction product. Then, it was washed with methanol and dried at 40 ° C under reduced pressure for 15 Hours, 410 g of polyamidic acid having a log viscosity of 0.87 dl / g and an imidization rate of 0% were obtained. 30 g of the obtained polyamidic acid was dissolved in 570 g of N-methyl-2-pyrrolidone, and 23.4 g was added thereto. Pyridine and 18.1 g of acetic anhydride were dehydrated and closed at 4 ° C for 4 hours at 110 ° C. Precipitation was performed in the same manner as above, washed, and dried under reduced pressure. Dry to obtain 17.5 g of polyfluorene imine with a logarithmic viscosity of 0.80 dl / g and a fluorene imidization rate of 100% (referred to as "polyfluorene" (A-1)). Synthesis Example 2 As tetracarboxylic acid di The acid anhydride was 224.1 7 g (0.5 mole) of 2,3,5_tricarboxycyclopentylacetic acid dianhydride, 157.14 g (0.5 mole) of 1,3,3 &amp;, 4,5,913-hexahydro-5-methyl- 5- (tetrahydro-2,5-dioxo-3-furyl) -naphtho [1,2, <]-furan-1,3-dione, 94.62 g (0.875 mole) as a diamine compound P-phenylenediamine, 24.85 g (0.1 mole) of bisaminopropyltetramethyldisilazane, 6.43 g (0.01 mole) of 3,6-bis (4-aminobenzyloxy) bile Nestane, 4.04 g (0.03 mole) of 4-aminophenyloctadecyl ether was dissolved in 4,500 g of N-methyl-2-pyrrolidone, and reacted at 60 ° C. for 6 hours. Then, the reaction solution was poured into a large amount The reaction product was precipitated in excess methanol. Then, by washing with methanol and drying under reduced pressure at 4 ° C. for 15 hours, 3 70 g of polyamidic acid having a log viscosity of 0.82 dl / g and a fluorinated imidization rate of 0% were obtained 30 g of the obtained polyamic acid was dissolved in 570 g of N-methyl-2-pyrrolidone, and 2 3.4 g of pyridine and 18.1 g of ethyl were added thereto. Anhydride is dehydrated and closed at 110 ° C for 4 hours. Precipitation, washing and drying under reduced pressure are carried out in the same manner as described above. -27- 200530376 gives 18.5 g of a log viscosity of 0.777 dl / g and a 100% imidization rate. Polyimide (referred to as "polyimide" (A-2)). Synthesis Example 3 As tetracarboxylic dianhydride, 218.12 g (1 mole) of pyromellitic acid anhydride 'was used as a diamine compound, 10.81 g (1 mole) of p-phenylene diamine was dissolved in 4,500 g of N-formaldehyde In 2-ylpyrrolidone, the reaction was carried out at 60 ° C for 6 hours. Then, the reaction solution was poured into a large amount of excess methanol to precipitate a reaction product. Then, it was washed with methanol and dried at 40 ° C for 15 hours under reduced pressure to obtain 4 10 g of polyamidoacid with a viscosity of 0.90 dl / g and an imidization rate of 0% (referred to as It is "Polyamic acid (B-1),"). Synthesis Example 4 Except for Synthesis Example 3, 109.06 (0.5 mole) pyromellitic dianhydride was used as tetracarboxylic dianhydride, and 98.06 g (0.5 mol) 485 g of polyamic acid was obtained in the same manner as in Synthesis Example 1 except for 1,2,3,4-cyclobutane tetraacid dicarboxylic anhydride (referred to as "polyamino acid (B-2)") Synthesis Example 5 ^ In the same manner as in Synthesis Example 3, except that 198.28 g (1 mol) of 4,4, · diaminodiphenylmethane was used as the diamine in Synthesis Example 3, polyamine was obtained. Acid (referred to as "polyamidoacid (B-3)"). Synthesis Example 6 Except that in Synthesis Example 3, 212 g (1.0 mol) of 2,2, _dimethyldiaminobiphenyl was used for the diamine. Except that in the same manner as in Synthesis Example 3, 475 g of poly (vinylamine) (referred to as "polyammonium acid (B-4)") was obtained. Comparative Synthesis Example 1 -28- 200530376 except that 196.12 g (1 mole) was used, 2,3,4-cyclobutane tetracarboxylic dianhydride as tetracarboxylic dianhydride, and 108.1 4 g (1 mole) of p-phenylenediamine as di Except for the amine compound, in the same manner as in Synthesis Example 3, 276 g of a polyamic acid having a log viscosity of 195 dl / g (referred to as "polyamino acid (B-5)") was obtained. Comparative Synthesis Example 2 except for using 314.28 g ( l mole) l, 3,3a, 4,5,9b-hexahydro-5-methyl-5- (tetrahydro-2,5-dioxo-3-furyl) -naphtho [l, 2 -c] furan-1,3-dione as tetracarboxylic dianhydride, 410.52 g (1.0 mole) of 2,2-bis [4- (4-aminophenoxy® group) phenyl] propane as diamine Except for the compound, in the same manner as in Synthesis Example 1, 300 g of a polyamic acid having a log viscosity of 0.83 dl / g (referred to as "polyamino acid (B-6)") was obtained. The same procedure was used as in Synthesis Example 2 The fluorene imidization reaction was performed in situ to obtain polyfluorene imine with a logarithmic viscosity of 1.28 dl / g (referred to as "polyfluorene (A-3),"). Example 1 The polyamidoimine (A-1) obtained in Synthesis Example 1 and the polyamidoacid (B-1) obtained in Synthesis Example 3 were dissolved in N-methyl-2-pyrrolidone / γ · butyrolactone ( 1/9) of the mixed gastrointestinal solvent is a solution having a solid content concentration of 4% by weight, and the solution is filtered with a sieve having a pore size of 1 μm to prepare a liquid crystal alignment agent. The liquid crystal alignment film coating printer for a liquid crystal alignment agent was coated on a transparent electrode surface of a glass substrate having a transparent electrode formed by ITO, and dried on a hot plate at 180 ° C for 10 minutes to form a dry average film thickness of 500 angstroms. Protective film. This protective film was immersed in an alignment film peeling solution containing a glycol-based solvent and a nonionic surfactant for 10 minutes, and the peelability was confirmed with the naked eye. As a result, it was peeled. This protective film was rubbed with a friction machine with a winding rayon cloth roller at a roll speed of -29-200530376, a tube rotation speed of 400 rpm, a platform moving speed of 3 cm / sec, and a brush press length of 0.4 mm for 10 times of rubbing treatment for resistance. As a result of the abrasiveness test, cutting and peeling were not confirmed. On the other hand, the above-mentioned alignment film-coated substrate subjected to the rubbing treatment was immersed in water for 1 minute, and then the two substrates were dried in a 100 ° C green furnace for 10 minutes. Then, a pair of liquid crystal alignment films with a friction-treated liquid crystal clamping substrate were arranged on the outer periphery of the liquid crystal alignment film with a diameter of 5.5 μm and an epoxy adhesive with divinylbenzene balls, and then the liquid crystal alignment was performed on the pair of liquid crystal clamping substrates. The films are relatively overlapped and crimped to cure the adhesive. Then, a nematic liquid crystal (Merck, MLC-622 1) was filled into the gap between the pair of substrates from the liquid crystal injection port®, and then the liquid crystal injection port was sealed with an acrylic light-curing adhesive, and adhered on both sides of the substrate. A polarizing plate to produce a liquid crystal display element. No flow alignment was seen. After the reliability test, no contrast spots or display defects were visible. Examples 2 to 8 and Comparative Examples 1 to 2 In addition to Synthesis Examples 2 to 6 which are used as a liquid crystal alignment film, Comparative Synthesis Examples 1, 2 and Polyurethane described in Examples 1 to 5 of Japanese Patent Application Laid-Open No. 8-22054 1 were used. A liquid crystal display device was produced in the same manner as in Example 1 except for polyamic acid and / or polyimide obtained from a liquid crystal alignment film formed of a mixed solution of an amine precursor solution and a soluble polyimide solution. In the examples and comparative examples, polyamidic acid and polyfluorene.imine were used at a ratio of polyamic acid: polyamidine = 4: 1 (weight ratio). The results are shown in Table 1. -30- 200530376 [Table i] Example / Comparative Example Polyimide Polyamic Acid Peeling Abrasion Resistance Alignment Reliability Example 2 A-2 B-1 Peelable No Cutting, Peeling No Flow Orientation No Comparison Spot, display defect Example 3 A-1 B-2 peelable without cutting, peeling without flow alignment without contrast spots, display defect Example 4 A-2 B-2 peelable without cutting, peeling without flow alignment without contrast spots, Significant weight: Defect Example 5 A-1 B-3 peelable without cutting, peeling without flow alignment without contrast spots, display defect Example 6 A-2 B-3 peelable without cutting, peeling without flow alignment without contrast spots, Example 7 A-1 B-4 Peelable without cutting, peeling without flow, without contrast spots, display defect Example 8 A-2 B-4 Peelable without cutting, peeling without flow, without contrast spots, display Defect Comparative Example 1 A-3 B-4 Cannot be peeled without cutting, Peeling without flow alignment without contrast spots, showing defects Comparative Example 2 A-3 B-4 Cannot be peeled without cutting, Peeling without flow alignment without contrast spots, Showing defects

-3 1-

Claims (1)

200530376-A 'X. Patent application scope: 1. A liquid crystal alignment agent, which is composed of fluorenimine-bonded units formed by the reaction of tetracarboxylic dianhydride and diamine, and A polymer or a mixture thereof comprising at least one bonding unit, characterized in that, for the polymer or a mixture thereof, the tetracarboxylic dianhydride contains a polymer selected from the group consisting of 1,2,3,4-cyclobutane tetracarboxylic dianhydride , 3,3,, 4,4, -Dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 3,5,6_tricarboxynorbornane-2-acetic acid Diacid anhydride, 2,3,4,5 · tetrahydrofurantetracarboxylic diacid anhydride, bicyclic [2.2.2] · • oct-7-ene-2,3,5,6-tetracarboxylic diacid anhydride, 1,3, 3 &amp;, 4,5,915-hexahydro-8-methyl-5- (tetrahydro-2,5 · dioxo-3 · furanyl) naphtho [l, 2-c] furan-1,3-di At least three of ketones and pyromellitic anhydride, and the diamine contains at least one selected from p-phenylenediamine, bisaminopropyltetramethyldisilazane, 4,4, -diaminodiphenyl Of methane, 2,2, -dimethyl-4,4'-diaminobiphenyl and 3,6-bis (4-aminobenzyloxy) choline 3 types. 2. The liquid crystal alignment agent according to item 1 of the scope of patent application, wherein the tetracarboxylic acid field contains at least 30% of pyromellitic acid anhydride. ® 3 · If the liquid crystal alignment agent of item 1 or 2 of the patent application scope, it also contains compounds with at least one epoxy group in the molecule. 4. A liquid crystal alignment film, which is formed of a liquid crystal alignment agent such as any one of items 1 to 3 of the scope of patent application. 5. A liquid crystal display device comprising a liquid crystal alignment film as described in item 4 of the patent application scope. -32- 200530376 7. Designated Representative Map: (1) The designated representative map in this case is: None. (2) A brief description of the component symbols in this representative figure: Μ 〇 8. If there is a chemical formula in this case, please disclose the chemical formula that best shows the characteristics of the invention: