TWI407211B - A liquid crystal alignment agent and a liquid crystal display device using the liquid crystal display device - Google Patents

Abstract

Disclosed is a soluble polyimide-based liquid crystal aligning agent which hardly causes damages on a film surface or separation of a film during rubbing. Specifically disclosed is a liquid crystal aligning agent which is applied over a substrate with electrode, then fired and subjected to rubbing for forming a liquid crystal alignment film. This liquid crystal aligning agent is characterized by containing a soluble polyimide obtained by imidating a polyamic acid which is obtained by reacting a diamine component with a tetracarboxylic acid dianhydride component. The liquid crystal aligning agent is further characterized in that the diamine component contains a diamine represented by the following general formula [1].

Description

Liquid crystal directional treatment agent and liquid crystal display element using same

The present invention relates to a liquid crystal alignment treatment agent for a liquid crystal display element produced by a polishing treatment step, and a liquid crystal alignment film and a liquid crystal display element thereof.

The liquid crystal display element is a structure in which liquid crystal molecules are held by a liquid crystal alignment film formed on a substrate, and a liquid crystal molecule which is oriented in a certain direction by a liquid crystal alignment film and a display element which is responsive to a voltage is used. In the liquid crystal alignment film, the surface of the polyimide film formed on the electrode substrate is usually formed by applying a pressure rubbing to the surface of the rayon or nylon cloth, and performing a so-called honing treatment. The polishing process determines the orientation direction of the liquid crystal molecules and the Pregru multi-angle, and the polishing process becomes a very important step.

A method of forming a polyimide film on an attached electrode substrate is a method of forming a coating film using a solution of a polyimide precursor such as polylysine, and performing a ruthenium imidization on a substrate, and using A method of imidizing a soluble polyimine solution.

Among them, a method of containing a soluble polyimine can form a polyimide film having good properties as a liquid crystal alignment film even at a lower temperature. On the contrary, the formed film has a low strength and is subjected to a grinding treatment to cause a problem that the film surface is easily scratched or the film is peeled off. The flaw or peeling of the surface of the liquid crystal alignment film is a cause of display failure when it is used as a liquid crystal display element, and is an extremely important problem.

Further, polyimine, in comparison with polyglycine, generally has poor solubility in an organic solvent, and it is difficult to form a uniform coating film in the case of imidization in advance, and is often used in a liquid crystal aligning agent. The solvent is insolubilized and cannot be contained in the liquid crystal aligning treatment agent. Therefore, it is also important that the liquid crystal aligning agent contains the solubility of the insoluble polyimine.

For the problem that the polishing treatment is likely to cause scratches on the surface of the film or peeling of the film, there is a method of adding a polyorganosiloxane derivative (for example, refer to Patent Document 1) or a method of adding a diazide-based compound (for example, refer to Patent Document 2) and the like.

Patent Document 1: Japanese Laid-Open Patent Publication No. Hei 6-308502

In view of the above-described circumstances, the present invention has been made to improve the solubility of polyimine in an organic solvent, to use it as a liquid crystal aligning agent, and to improve the polishing resistance of the obtained coating film. That is, the present invention has an object of providing a soluble polyimine-based liquid crystal aligning treatment agent which is hard to cause film surface scratches or peeling of a film by a rubbing treatment.

In order to achieve the above object, the working colleagues of the present invention have completed the present invention by intensively discussing the results of continuous research. That is, the gist of the present invention is as follows.

(1) A liquid crystal aligning treatment agent which is a liquid crystal aligning treatment agent for a liquid crystal alignment film which is applied to a substrate to which an electrode is attached, which is subjected to firing and polishing treatment, and is characterized in that it contains a diamine component and a tetracarboxylic acid The polyimine which is obtained by the reaction of an anhydride component and which is ruthenium imidized, and the diamine component contains the diamine represented by the following general formula [1].

(2) The liquid crystal aligning agent according to the above (1), wherein the diamine component contains 20 mol% or more of the diamine represented by the general formula [1].

(3) The liquid crystal aligning agent according to the above (1) or (2), wherein the tetracarboxylic dianhydride component contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure.

(4) The liquid crystal aligning agent according to any one of the above aspects, wherein the tetracarboxylic dianhydride component contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure. With aromatic tetracarboxylic dianhydride.

(5) The liquid crystal aligning agent according to any one of the above aspects, wherein the polyamic acid is a tetracarboxylic dianhydride component and the diamine component is 1:0.8 to 1:1.2. The molar ratio is obtained by reacting.

(6) The liquid crystal aligning agent according to any one of the above (1), wherein the poly-proline is subjected to a ruthenium iodide reaction in the presence of a basic catalyst and an acid anhydride. Made of soluble polyimine.

(7) The liquid crystal aligning agent according to the above (6), wherein the soluble polyimine has a weight average molecular weight of 2,000 to 200,000.

(8) The liquid crystal aligning agent according to the above (6) or (7), wherein the soluble polyimine has a hydrazine imidization ratio of 40% or more.

(9) A liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to any one of the above items (1) to (8) to a substrate on which an electrode is attached, and firing and polishing.

(10) A liquid crystal display element obtained by using the liquid crystal alignment film of the above (9).

The liquid crystal aligning agent of the present invention can form a polyimide film having excellent properties as a liquid crystal alignment film even when fired at a low temperature. Further, since the flaw on the surface of the film during the polishing treatment or the peeling of the film is extremely small, a liquid crystal display element having excellent characteristics with little display failure can be obtained.

Further, the soluble polyimine contained in the liquid crystal aligning agent of the present invention can improve the solubility in a solvent commonly used for a liquid crystal aligning agent such as N-methyl-2-pyrrolidone or γ-butyrolactone. Therefore, the selection range of the combination of the tetracarboxylic dianhydride component and the diamine component for the soluble polyimine can be expanded. Therefore, by appropriately selecting these, it is possible to provide a liquid crystal alignment treatment agent which is excellent in properties other than the polishing resistance.

[Embodiment of the Invention]

The details of the invention are as follows.

The liquid crystal aligning agent of the present invention is a composition used for forming a liquid crystal alignment film by coating on a fixed electrode substrate and baking and polishing. Further, the liquid crystal aligning agent of the present invention is characterized in that it comprises a soluble polyimine which is obtained by reacting a polyamine derivative with a polyamine component to react with a tetracarboxylic dianhydride component, wherein the diamine component is contained. Containing the diamine represented by the following general formula [1]

The diamine represented by the general formula [1] is not particularly limited in the position of each substituent on the benzene ring, and the positional relationship of the two amine groups is preferably a meta or a para position. The preferred specific examples of the diamine described below are not limited thereto.

In the present invention, the diamine component which is a raw material of the soluble polyimine may be a diamine represented by the general formula [1], and may be one or a combination of two or more selected from the other diamines. When the diamine component of the soluble polyimine is contained and the diamine represented by the general formula [1] is contained, the problem of the surface of the film when the coating film is polished or the peeling of the film can be improved, and at the same time, the film can be improved. The solubility of polyimine in organic solvents.

Among the above diamine components, the diamine represented by the general formula [1] is preferably 20 mol% or more, more preferably 40 mol% or more, and most preferably 50 mol% or more, based on the entire diamine component. The higher the ratio of the diamine represented by the general formula [1], the higher the effect of suppressing the scratch on the surface of the oriented film or the peeling of the film during the polishing treatment, and the solubility of the soluble polyimine in the organic solvent is also improved.

Among the above diamine components, the diamine used in combination with the diamine represented by the general formula [1] is not particularly limited. This is specifically described below.

Examples of the alicyclic diamine are 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4'-diaminodicyclohexylmethane, 4,4'-di Amino-3,3'-dimethyldicyclohexylamine, isophoronediamine, and the like.

Examples of the aromatic diamine include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, and 3,5-diaminotoluene. 1,4-Diamino-2-methoxybenzene, 2,5-diamino-p-xylene, 1,3-diamino-4-chlorobenzene, 3,5-diaminobenzoic acid , 1,4-diamino-2,5-dichlorobenzene, 4,4'-diamino-1,2-diphenylethane, 4,4'-diamino-2,2'- Dimethylbiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'- Diamino-3,3'-dimethyldiphenylmethane, 2,2'-diaminopurine, 4,4'-diaminopurine, 4,4'-diaminodiphenyl ether, 3,4'-Diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenylanthracene, 3,3'-diaminodiphenyl Base, 4,4'-diaminobenzophenone, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1, 4-bis(4-aminophenoxy)benzene, 3,5-bis(4-aminophenoxy)benzoic acid, 4,4'-bis(4-aminophenoxy)bibenzyl, 2 ,2-bis[(4-amino group) Phenoxy)methyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis[4-(4-aminophenoxy) Phenyl]propane, bis[4-(3-aminophenoxy)phenyl]anthracene, bis[4-(4-aminophenoxy)phenyl]anthracene, 1,1-bis(4-amine Phenyl)cyclohexane, α,α'-bis(4-aminophenyl)-1,4-diisopropylbenzene, 9,9-bis(4-aminophenyl)anthracene, 2, 2-bis(3-aminophenyl)hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-diaminodiphenylamine, 2,4-di Aminodiphenylamine, 1,8-diaminonaphthalene, 1,5-diaminonaphthalene, 1,5-diaminoguanidine, 1,3-diaminopurine, 1,6-diamino Anthracene, 1,8-diaminopurine, 2,7-diaminoguanidine, 1,3-bis(4-aminophenyl)tetramethyldioxane, benzidine, 2,2'-di Methyl benzidine, 1,2-bis(4-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,4-bis(4-aminophenyl)butyl Alkane, 1,5-bis(4-aminophenyl)pentane, 1,6-bis(4-aminophenyl)hexane, 1,7-bis(4-aminophenyl)heptane, 1,8-bis(4-aminophenyl)octane, 1,9-bis(4-amine Phenyl)decane, 1,10-bis(4-aminophenyl)decane, 1,3-bis(4-aminophenoxy)propane, 1,4-bis(4-aminophenoxyl) Butane, 1,5-bis(4-aminophenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,7-bis(4-aminobenzene) Oxy) heptane, 1,8-bis(4-aminophenoxy)octane, 1,9-bis(4-aminophenoxy)decane, 1,10-bis(4-amine Phenoxy)decane, bis(4-aminophenyl)propane-1,3-diolate, bis(4-aminophenyl)butane-1,4-diolate, di( 4-aminophenyl)pentane-1,5-diolate, bis(4-aminophenyl)hexane-1,6-diolate, bis(4-aminophenyl)g Alkane-1,7-diolate, bis(4-aminophenyl)octane-1,8-diolate, bis(4-aminophenyl)decane-1,9-diol Acid ester, bis(4-aminophenyl)decane-1,10-diolate, 1,3-bis[4-(4-aminophenoxy)phenoxy]propane, 1,4 - bis[4-(4-aminophenoxy)phenoxy]butane, 1,5-bis[4-(4-aminophenoxy)phenoxy]pentane, 1,6-double [4-(4-Aminophenoxy)phenoxy]hexane, 1,7- [4-(4-Aminophenoxy)phenoxy]heptane, 1,8-bis[4-(4-aminophenoxy)phenoxy]octane, 1,9-bis[4 -(4-Aminophenoxy)phenoxy]nonane, 1,10-bis[4-(4-aminophenyloxy)phenyl]nonane, and the like.

Examples of heterocyclic diamines are 2,6-diaminopyridine, 2,4-diaminopyridine, 2,4-diamino-1,3,5-triazine, 2,7-diamine. Dibenzofuran, 3,6-diaminocarbazole, 2,4-diamino-6-isopropyl-1,3,5-triazine, 2,5-bis(4-amino Phenyl)-1,3,4-oxadiazole and the like.

Examples of the aliphatic diamines are 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6 -diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminodecane, 1,10-diaminodecane, 1,3 -diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7-diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1,9-diamino-5-methylheptane, 1, 12-Diamino(dodecane), 1,18-diamino(octadecyl), 1,2-bis(3-aminopropoxy)ethane, and the like.

Further, in order to increase the Pregrudogan angle of the liquid crystal, a diamine having a specific substituent may be used in combination. Substituents which can increase the Preigluo's angle of the liquid crystal include a long-chain alkyl group, a perfluoroalkyl group, an aromatic cyclic group, an aliphatic cyclic group, a combination of these substituents, a steroid skeleton group, and the like. The following specific examples of the diamine having such a substituent are not limited thereto. Further, in the structure exemplified below, j is an integer of 5 to 20; k is an integer of 1 to 20.

In the present invention, the tetracarboxylic dianhydride component which is a raw material of the soluble polyimine may be a tetracarboxylic dianhydride or a mixture of two or more kinds of tetracarboxylic dianhydride.

The effect of improving the problem of the flaw on the surface of the liquid crystal alignment film or the peeling of the film which occurs in the polishing treatment of the present invention is not limited to tetracarboxylic dianhydride.

However, from the point of view of the polyamidimide of the stilbene imidization ratio, the point of the soluble polyimine which is highly soluble, and the point which can improve the voltage holding ratio of the liquid crystal element, etc. A tetracarboxylic dianhydride of a structure or an aliphatic structure is preferred. The tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure is 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4- Cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2, 3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, 1,2,4 , 5-cyclohexanetetracarboxylic dianhydride, 3,4-dicarboxy-1-cyclohexyl succinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene Succinic dianhydride, 1,2,3,4-butane tetracarboxylic dianhydride, bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride, 3,3' , 4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, cis-3,7-dibutylcyclooctane-1,5-diene-1 , 2,5,6-tetracarboxylic dianhydride, tricyclo[4.1.1.0 ^{2 , 5} ]decane-3,4,7,8-tetracarboxylic acid-3,4:7,8-dianhydride, six Ring [6.6.0.1 ^{2 , 7} .0 ^{3 , 6} .1 ^{9 , 1 4} .0 ^{1 0 , 1 3} ] (hexadecane)-4,5,11,12-tetracarboxylic acid-4,5:11 , 12-dianhydride and the like.

Further, when the aromatic tetracarboxylic dianhydride is used in combination, the liquid crystal orientation can be improved and the accumulated charge of the liquid crystal element can be reduced. Aromatic tetracarboxylic dianhydrides, pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,2'3,3'-biphenyltetracarboxylic dianhydride , 2,3,3',4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 2,3,3',4'-di Benzophenone tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, bis(3,4-dicarboxyphenyl)ruthenium anhydride, 1,2,5,6-naphthalene tetracarboxylate Acid dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, and the like.

When considering the solubility of soluble polyimine, the balance of liquid crystal orientation, voltage retention, and accumulated charge, tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure, and aromatic tetracarboxylic acid The ratio of dianhydride, the former/the latter is preferably 90/10 to 50/50, more preferably 80/20 to 60/40.

The soluble polyimine used in the liquid crystal aligning agent of the present invention is a polyimine which is obtained by reacting the above diamine component with a tetracarboxylic dianhydride component to obtain a ruthenium imidization. Here, a reaction of polyglycine is carried out, and the tetracarboxylic dianhydride component and the diamine component can be mixed in an organic solvent.

The method for mixing the tetracarboxylic dianhydride component and the diamine component in an organic solvent is as follows: (1) stirring a solution in which the diamine component is dispersed or dissolved in an organic solvent, directly adding, or dispersing or dissolving or dissolving in an organic solvent, and adding four a method of carboxylic acid dianhydride; (2) a method of dispersing or dissolving a solution of a tetracarboxylic dianhydride in an organic solvent, and a method of adding a diamine component; (3) a method of mutually adding a tetracarboxylic dianhydride component and a diamine component Wait.

Further, when the tetracarboxylic dianhydride component or the diamine component is formed of a plurality of compounds, the plurality of components may be polymerized in a mixed state in advance, or the polymerization may be carried out individually in sequence.

The temperature at which the tetracarboxylic dianhydride component and the diamine component are polymerized in an organic solvent is usually 0 to 150 ° C, preferably 5 to 100 ° C, more preferably 10 to 80 ° C. The higher the temperature, the earlier the polymerization is completed, but when it is too high, there is a case where a polymer having a high molecular weight cannot be obtained.

Further, although the polymerization reaction can be carried out at a random concentration, when the concentration is too low, it is difficult to obtain a polymer having a high molecular weight; when the concentration is too high, the viscosity of the reaction liquid is too high, and uniform stirring is difficult. A preferred concentration is from 1 to 50% by weight, more preferably from 5 to 30% by weight. It can be carried out at a high concentration in the initial stage of the polymerization reaction, and then an organic solvent is added.

The organic solvent used in the above reaction is not particularly limited as long as it can dissolve the produced polylysine. Specific examples thereof include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, and dimethyl hydrazine. , tetramethyl urea, pyridine, dimethyl hydrazine, hexamethylarylene, γ-butyrolactone and the like. These can be used singly or in combination. Further, even if the solvent of the poly-proline is not dissolved, it can be used in the above solvent in the range in which the produced polyamine is not precipitated.

Further, the water content in the organic solvent hinders the polymerization reaction, and further causes the hydrolysis of the produced polylysine, and the organic solvent is preferably used by dehydration drying as much as possible.

The ratio of the tetracarboxylic dianhydride component to the diamine component used in the polymerization of polylysine is preferably from 1:0.8 to 1:1.2, and the molar ratio is closer to 1:1. The greater the molecular weight of the amine acid. When the molecular weight of the polyaminic acid is controlled, the molecular weight of the soluble polyimine obtained after the imidization can be adjusted.

The molecular weight of the soluble polyimine contained in the liquid crystal aligning agent of the present invention is not particularly limited, and the weight average molecular weight is 2,000 Å from the viewpoint of the strength of the coating film and the ease of handling as a liquid crystal aligning agent. 200,000 is preferred, and more preferably 5,000 to 50,000.

The ruthenium imidization of the polyglycolic acid obtained above can be stirred for 1 to 100 hours in the presence of an alkaline catalyst and an acid anhydride in an organic solvent.

The basic catalyst is pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine and the like. Among them, a basic pyridine which is suitable for carrying out the reaction is preferred. Further, the acid anhydride may be acetic anhydride, trimellitic anhydride or pyromellitic anhydride. Among them, acetic acid anhydride is very suitable after the imidization of ruthenium, and the obtained polyimine is easy to be refined. As the organic solvent, a solvent used in the polymerization of the above polyamic acid can be used.

The imidization ratio of the soluble polyimine can be controlled by adjusting the amount of the catalyst, the reaction temperature, and the reaction time. The amount of the alkaline catalyst at this time is preferably 0.2 to 10 times moles of the proline group, more preferably 0.5 to 5 times moles. Further, the amount of the acid anhydride is preferably from 1 to 30 times the molar amount of the prolyl group, more preferably from 1 to 10 times the mole. The reaction temperature is preferably -20 to 250 ° C, more preferably 0 to 180 ° C.

The sulfonium imidization ratio of the soluble polyimine contained in the liquid crystal aligning agent of the present invention is not particularly limited, and is preferably 40% or more; more preferably 60% or more for obtaining a high voltage holding ratio, more preferably More than 80%.

In the solution of the soluble polyimine thus obtained, the added catalyst and the like are left to recover the soluble polyimine. After washing, it is preferred to use the liquid crystal aligning agent of the present invention.

The recovery of the soluble polyimine can be carried out by stirring the solution of the ruthenium iodide into a weak solvent and filtering after the precipitation of the polyimine. The weak solvent at this time includes methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and the like. The washing of the recovered soluble polyimine can also be carried out using this weak solvent.

So recycled. The washed polyimine can be dried at room temperature or under reduced pressure to a powder under normal pressure or reduced pressure.

There is no restriction on the method of preparing the liquid crystal aligning agent of the present invention. An example of this is a method in which the soluble polyimine powder obtained above is redissolved in an organic solvent to form a polyimine solution; and then diluted to a desired concentration. In this dilution step, adjustment of the solvent composition for controlling the coating property to the substrate or addition of an additive for improving the coating film properties may be performed. Further, a solution of a solution of a soluble polyimine of the above-described different structure or a solution of a polyaminic acid can be carried out, and another resin component can be added.

The concentration of the soluble polyimine in the liquid crystal aligning agent varies depending on the thickness of the liquid crystal alignment film formed or the content of other solid content, and is preferably 1 to 10% by weight to form a good liquid crystal alignment film. It is more suitable for 3~10% by weight.

The organic solvent for redissolving the polyimine powder is N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylhexene. Indoleamine, 2-pyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl hydrazine, tetramethyl urea, dimethyl hydrazine, hexamethylarylene, γ-butyrolactone, 1,3 - Dimethyl imidazolidinone and the like.

Solvents added to control the coating properties of the substrate include ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethyl carbitol acetate, ethylene glycol, 1 -Methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol Diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, Methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, and the like. Although these solvents also contain a solvent which cannot dissolve the soluble polyimine alone, they may be mixed with the liquid crystal aligning agent of the present invention in the range in which no polyimine is precipitated. In particular, by appropriately mixing a solvent having a low surface tension, the uniformity of the coating film at the time of coating the substrate can be improved, and it is suitably used in the liquid crystal aligning treatment agent of the present invention.

Additives for improving the properties of the coating film include 3-aminopropylmethyldiethoxydecane, 3-phenylaminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, (amine) A decane coupling agent such as ethylethylaminomethyl)phenethyltrimethoxydecane. By adding such a decane coupling agent, the adhesion to the coating film of the substrate can be further improved.

The solid content concentration of the liquid crystal aligning agent of the present invention can be appropriately adjusted depending on the thickness of the liquid crystal alignment film to be formed, and is preferably 1 to 10% by weight. When it is less than 1% by weight, it is difficult to form a uniform and defect-free coating film; when it is more than 10% by weight, the storage stability of the solution may be deteriorated.

The liquid crystal aligning agent obtained as described above is preferably filtered before being applied to the substrate.

The liquid crystal aligning agent of the present invention can be applied to a substrate, dried, and fired to form a coating; thereby, the coating film surface can be subjected to a polishing treatment to obtain a liquid crystal alignment film.

In this case, when the substrate to be used is a substrate having high transparency, it is not particularly limited, and a plastic substrate such as a glass substrate, an acrylic substrate, or a polycarbonate substrate can be used. The use of a substrate such as an ITO electrode driven by a liquid crystal is particularly suitable from the viewpoint of process simplification. Further, it is also possible to use an opaque person such as a germanium wafer formed of only one side of the reflective liquid crystal display element. In the case of the electrode, a material that reflects light such as aluminum can be used.

The coating method of the liquid crystal aligning agent is a spin coating method, a printing method, an inkjet method, or the like. From the viewpoint of productivity, a flexible printing method widely used in the industry is also suitable for use in the liquid crystal aligning treatment agent of the present invention.

The drying step after the application of the liquid crystal aligning agent is not necessarily necessary. However, it is preferable to include a drying step in the case where the time from the application to the completion of the baking is not fixed to each of the substrates or the case where the baking is not performed after the application. This drying is preferably performed by evaporating the solvent to such a degree that the shape of the coating film is not deformed by the substrate or the like. The drying method is not particularly limited. Specifically, it is dried on a hot plate at 50 to 150 ° C, preferably 80 to 120 ° C for 0.5 to 30 minutes, preferably 1 to 5 minutes.

The baking of the substrate coated with the liquid crystal aligning agent can be carried out at a random temperature of 100 to 350 °C. It is preferably 150 to 300 ° C, more preferably 180 to 250 ° C. In the case where a proline group is present in the liquid crystal aligning agent, the conversion rate from the conversion of lysine to quinone is changed due to the firing temperature, and the liquid crystal aligning agent of the present invention does not require 100% of the imine. Chemical. However, it is preferable to burn it at a temperature higher than the heat treatment temperature of the sealant hardening or the like by 10 ° C or more, which is necessary in the liquid crystal element manufacturing step.

When the thickness of the coating film after firing is too thick, the power consumption of the liquid crystal display element is unfavorable, and when the thickness is too thin, the reliability of the liquid crystal display element may be lowered. It is preferably 10 to 200 nm, more preferably 50 to 100 nm.

An existing polishing apparatus can be used for the polishing treatment of the coating film surface formed on the above substrate. The material of the polishing cloth at this time is cotton, rayon, nylon, and the like.

In the liquid crystal display device of the present invention, after the liquid crystal alignment film substrate is attached by the liquid crystal alignment treatment agent of the present invention, the liquid crystal element is used as a liquid crystal display element by a known method.

For example, in the case of fabricating a liquid crystal element, generally, a pair of substrates forming a liquid crystal alignment film is preferably 1 to 30 μm, more preferably 2 to 10 μm, and the polishing direction is set at 0 to 270. °C The random angle is fixed by the sealant, injected into the liquid crystal, and closed.

The method of injecting the liquid crystal is not particularly limited, and a vacuum method in which a liquid crystal element is produced by depressurization and then injected into a liquid crystal, a dropping method in which a liquid crystal is dropped, and a closed method is performed.

The liquid crystal display element thus obtained can reduce the display defect of the liquid crystal alignment film or the peeling of the film which occurs during the polishing process, and can be a highly reliable liquid crystal display device. Moreover, it can be suitably used for a TN liquid crystal display element, an STN liquid crystal display element, a TFT liquid crystal display element, an OCB liquid crystal display element, and a horizontal electric field type liquid crystal display element.

The invention is illustrated in more detail by way of examples. The present invention is not limited to these and the like.

[Examples]

Description of symbols used in the examples or comparative examples.

<tetracarboxylic dianhydride>CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride TDA: 3,4-dicarboxy-1,2,34-tetrahydro-1-naphthalene succinic acid Anhydride BODA: bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride PMDA: pyromellitic dianhydride

<Diamine> 2,4-DAA: 2,4-Diamino-N,N-diallylaniline p-PDA: p-phenylenediamine PCH7AB: 4-[4-(4-heptylcyclohexyl) Phenoxy]-1,3-diaminobenzene C12DAB: 4-(dodecyl)oxy-1,3-diaminobenzene C18DAB: 4-(octadecyl)oxy-1,3- Aminobenzene 4-ABA: 4-aminobenzylamine DDM: 4,4'-diaminodiphenylmethane C14DAB: 4-(tetradecyl)alkyloxy-1,3-diaminobenzene 3- ABA: 3-aminobenzylamine

<Organic solvent> NMP: N-methyl-2-pyrrolidone γ BL: γ-butyrolactone DPM: dipropylene glycol monomethyl ether

<Structure>

<Measurement of Molecular Weight> The molecular weight of the soluble polyimine was measured by a GPC (normal temperature gel permeation chromatography) apparatus, and the number average molecular weight and the weight average molecular weight were calculated as polyethylene glycol and polyethylene oxide. Alkane converted value.

GPC device: Shouxi Scientific Co., Ltd. (SSC-7200) Column: Shodex Co., Ltd. (KD803, KD805 series) Column temperature: 50 °C Eluent: N,N-dimethylformamide [Additive lithium bromide Hydrate (LiBr.H ₂ O) 30 mmol / L, phosphoric acid. Anhydrous crystals (o-phosphoric acid) 30 mmol/L, tetrahydrofuran (THF) 10 ml/l] Flow rate: 1.0 ml/min Standard sample for calibration line: Tosoh Corporation, TSK, standard polyethylene oxide (molecular weight About 900,000, 150,000, 100,000, 30,000) and polymer laboratory company, polyethylene glycol (molecular weight of about 12,000, 4,000, 1,000)

<Determination of the imidization ratio> The imidization ratio of the soluble polyimine was dissolved in d ₆ -DMSO (dimethyl sulfonium-d ₆ ), and ¹ H-NMR was measured. From the ratio of the cumulative values of the proton peaks, the ratio of the proline groups remaining without imidization was calculated.

[Example 1]

Using tetracarboxylic dianhydride component TDA 30.03g (0.100 mol), diamine component p-PDA 7.57g (0.070 mol), and 2,4-DAA 6.10g (0.030 mol), in NMP 174.80g, The reaction was carried out for 24 hours at room temperature to obtain a polyaminic acid solution.

To 15.09 g of the polyamic acid solution, 25.67 g of NMP was added and diluted, and 2.29 g of acetic anhydride and 0.97 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 154.1 ml of methanol to precipitate, and the solid matter was recovered. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 9,508 and a weight average molecular weight of 19,629. The yield of hydrazine was 97%.

To 2.02 g of the above-obtained soluble polyimine, 18.18 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 6.73 g of γ BL and 6.73 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

<Evaluation of Grinding Resistance> The liquid crystal aligning agent was spin-coated on a glass substrate with a transparent electrode, dried on a hot plate at 80 ° C for 5 minutes, and then fired in a hot air circulating oven at 230 ° C for 30 minutes to form. A film having a film thickness of 100 nm. This coating film surface was pulverized by a pulverizing apparatus having a drum diameter of 120 mm, and was ground at a drum rotation speed of 500 rpm, a drum speed of 50 mm/sec, and a press-in amount of 0.3 mm, whereby a liquid crystal alignment film substrate was attached.

The film surface of the liquid crystal alignment film was observed 2,000 times with a confocal laser microscope, and no scratch or peeling of the film was observed.

Further, the observation of the surface of the film was carried out using a laser laser microscope 1LM21D manufactured by Laser Technology.

[Embodiment 2]

Using tetracarboxylic dianhydride component CBDA 11.53g (0.059 mol) and TDA 18.02g (0.060 mol); diamine component 4-ABA 11.73g (0.096 mol), and 2,4-DAA 4.88g (0.024 mol) The reaction was carried out for 24 hours at room temperature in NMP 261.60 g to obtain a polyamidonic acid solution.

To 27.47 g of the polyamic acid solution, 41.60 g of NMP was added and diluted, and 11.84 g of acetic anhydride and 5.50 g of pyridine were added, and the mixture was reacted at 35 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 259.9 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 13,379 g and a weight average molecular weight of 32,132. Further, the sulfhydrylation rate was 79%.

To 1.82 g of the above-obtained soluble polyimine, 16.38 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours, and the soluble polyimine was completely dissolved at the end of stirring. After the solution was cooled to room temperature, 6.07 g of γ BL and 6.07 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

As a result of evaluation of the polishing resistance in the same manner as in Example 1 using this liquid crystal alignment treatment agent, no scratches or peeling of the film were observed in the liquid crystal alignment film.

[Comparative Example 1]

Using tetracarboxylic dianhydride component TDA 30.03g (0.100 mol), diamine component p-PDA 10.81g (0.100 mol), in NMP 163.40g, reacting at room temperature for 24 hours, to obtain poly-proline Solution.

To 15.09 g of the polyamic acid solution, 25.67 g of NMP was added and diluted, and 2.29 g of acetic anhydride and 0.97 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 154.1 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 7,424 and a weight average molecular weight of 18,681. The yield of hydrazine was 96%.

To 2.02 g of the above-obtained soluble polyimine, 18.18 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours, and the soluble polyimine was completely dissolved at the end of stirring. After the solution was cooled to room temperature, 6.73 g of γ BL and 6.73 g of DPM were added and stirred sufficiently as a solution of soluble polyamidiamine of 6 wt% and DPM of 20 wt%, which is a liquid crystal directional treatment agent for comparison. .

As a result of evaluation of the polishing resistance in the same manner as in Example 1 using the liquid crystal aligning agent, a number of scratches were observed on the surface of the liquid crystal alignment film, and it was confirmed that the polishing resistance was higher than that of the liquid crystal aligning agent of Example 1 or Example 2. The resulting coating film was poor.

[Comparative Example 2]

Using tetracarboxylic dianhydride component CBDA 11.30g (0.058 mol) and TDA 18.02g (0.060 mol); diamine component 4-ABA 14.66g (0.120 mol), in NMP 249.20g, reaction at room temperature 24 In hours, a polyamine solution is obtained.

To 26.01 g of the polyamic acid solution, 39.63 g of NMP was added and diluted, and 11.84 g of acetic anhydride and 5.50 g of pyridine were added, and the mixture was reacted at 35 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 249.3 ml of methanol to recover a precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 11,824 and a weight average molecular weight of 29,019. The yield of hydrazine was 81%.

To 1.85 g of the above-obtained soluble polyimine, 16.65 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 6.17 g of γ BL and 6.17 g of DPM were added and sufficiently stirred to obtain a solution of 6 wt% of soluble polyimine and 20 wt% of DPM, which is a liquid crystal aligning agent for comparison.

As a result of evaluation of the polishing resistance in the same manner as in Example 1 using the liquid crystal aligning agent, a number of scratches were observed on the surface of the liquid crystal alignment film, and it was confirmed that the polishing resistance was higher than that of the liquid crystal aligning agent of Example 1 or Example 2. The resulting coating film was poor.

[Example 3]

Using tetracarboxylic dianhydride component TDA 42.04g (0.140 mol), diamine component p-PDA 7.57g (0.070 mol) and 2,4-DAA 14.20g (0.070 mol), in NMP 255.40g, in the room The reaction was carried out for 24 hours at a temperature to obtain a polyamidonic acid solution.

To 13.39 g of the polyamic acid solution, 22.85 g of NMP was added and diluted, and 1.95 g of acetic anhydride and 0.83 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 136.6 ml of methanol to recover a precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 10,522 and a weight average molecular weight of 25,220. The yield of hydrazine was 97%.

To 1.77 g of the above-obtained soluble polyimine, 15.93 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 5.90 g of γ BL and 5.90 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the grinding conditions were stronger than those of Example 1. The drum speed is 1000 rpm, the drum speed is 50 mm/sec, and the press-in amount is 0.5 mm. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Example 4]

Using a tetracarboxylic dianhydride component of CBDA 19.41 g (0.099 mol) and a diamine component of 2,4-DAA 20.33 g (0.100 mol), the reaction was carried out at room temperature for 24 hours in NMP 159.00 g to obtain a polyfluorene. Amino acid solution.

To 25.13 g of the polyamic acid solution, 38.79 g of NMP was added and diluted, and 3.94 g of acetic anhydride and 1.68 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 243.4 ml of methanol to recover the precipitated solid matter. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 10,122 and a weight average molecular weight of 21,004. The yield of hydrazine was 97%.

To 2.50 g of the above-obtained soluble polyimine, 22.50 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, γBL 8, 33 g, and DPM 8.33 g were added and stirred well to obtain a solution of 6 wt% of soluble polyimine and 20 wt% of DPM, thereby obtaining a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Comparative Example 3]

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using the liquid crystal aligning agent prepared in Comparative Example 1. However, the polishing conditions were as strong as in Example 3. As a result, the surface of the liquid crystal alignment film was confirmed to have numerous flaws.

[Comparative Example 4]

Using tetracarboxylic dianhydride component TDA 30.03g (0.100 mol), diamine component p-PAA 5.14g (0.048 mol) and DMM 9.91g (0.050 mol), in NMP 181.40g, react at room temperature 24 In hours, a polyamine solution is obtained.

To 20.82 g of the polyamic acid solution, 21.47 g of NMP was added and diluted, and 7.61 g of acetic anhydride and 3.54 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 154.1 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 9,508 and a weight average molecular weight of 19,629. The yield of hydrazine was 98%.

To 2.05 g of the above-obtained soluble polyimine, 18.45 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 6.83 g of γ BL and 6.83 g of DPM were added and sufficiently stirred to obtain a solution of 6 wt% of soluble polyimine and 20 wt% of DPM, which is a liquid crystal aligning agent for comparison.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, numerous flaws were confirmed on the surface of the liquid crystal alignment film.

[Comparative Example 5]

Using a tetracarboxylic dianhydride component of CBDA 22.59 g (0.115 mol), a diamine component of 4-ABA 14.66 g (0.120 mol), and reacting at room temperature for 24 hours in NMP 211.10 g, a polylysine is obtained. Solution.

In 21.22 g of this polyaminic acid solution, 22.74 g of NMP was added and diluted, and 10.12 g of acetic anhydride and 4.71 g of pyridine were added, and the reaction was carried out at 50 ° C, and gelation was carried out in 30 minutes, and no soluble polyimine was obtained. .

Therefore, the polyphosphoric acid solution was diluted again, and the temperature of the hydrazide reaction was lowered to 35 ° C for 3 hours.

After the reaction solution was cooled to room temperature, it was poured into 205.7 ml of methanol to recover a precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 12,944 and a weight average molecular weight of 30,081. The yield of hydrazine was 78%.

To 1.64 g of the above-obtained soluble polyimine, 14.76 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The undissolved polyimine was left at the end of the stirring, and the solubility of the soluble polyimine was confirmed to be poor as compared with Example 4.

[Example 5]

Using tetracarboxylic dianhydride component CBDA14.12g (0.072 mol) and TDA 22.52g (0.075 mol), diamine component p-PDA 8.11g (0.075 mol) and 2,4-DAA 15.25g (0.075 mol), The reaction was carried out at room temperature for 24 hours in NMP 240.00 g to obtain a polyaminic acid solution.

To 21.48 g of this polyaminic acid solution, 37.67 g of NMP was added and diluted, and 3.62 g of acetic anhydride and 1.54 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 225.1 ml of methanol, and the precipitated solid matter was recovered. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 13,735 and a weight average molecular weight of 28,273. The yield of hydrazine was 97%.

To 2.75 g of the above-obtained soluble polyimine, 24.75 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 9.17 g of γ BL and 9.17 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Embodiment 6]

Using tetracarboxylic dianhydride component CBDA 11.11g (0.057 mol) and TDA 18.02g (0.060 mol), diamine component p-PDA 6.49g (0.060 mol), PCH7AB 2.28g (0.006 mol) and 2,4- DAA 10.98 g (0.054 mol) was reacted at room temperature for 24 hours in NMP 195.30 g to obtain a polyaminic acid solution.

To 20.77 g of the polyamic acid solution, 30.82 g of NMP was added and diluted, and 3.11 g of acetic anhydride and 1.32 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 196.1 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 8,550 and a weight average molecular weight of 16,005. The yield of hydrazine was 98%.

To 2.31 g of the above-obtained soluble polyimine, 20.79 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 7.70 g of γ BL and 7.70 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Embodiment 7]

Using tetracarboxylic dianhydride component CBDA 9.41g (0.048 mol) and PMDA 10.91g (0.050 mol), diamine component 2,4-DAA 20.33g (0.100 mol), in NMP 162.60g, at room temperature After reacting for 24 hours, a polyaminic acid solution was obtained.

To 17.10 g of the polyamic acid solution, 21.40 g of NMP was added and diluted, and 2.30 g of acetic anhydride and 0.98 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 146.2 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a yellow-white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 11,673 and a weight average molecular weight of 23,037. The yield of hydrazine was 94%.

To 2.50 g of the above-obtained soluble polyimine, 22.50 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 8.33 g of γ BL and 8.33 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Embodiment 8]

Using tetracarboxylic dianhydride component CBDA 19.89g (0.101 mol) and PMDA 5.67g (0.026 mol), diamine component 4-ABA 6.35g (0.052 mol) and 2,4-DAA 15.86g (0.078 mol), In NMP 191.10g, the reaction was carried out at room temperature for 24 hours to obtain a polyaminic acid solution.

To 17.39 g of the polyamic acid solution, 27.30 g of NMP was added and diluted, and 2.98 g of acetic anhydride and 1.27 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 171.3 ml of methanol to recover a precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a yellow-white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 11,471 and a weight average molecular weight of 28,400. The yield of hydrazine was 94%.

To 2.05 g of the above-obtained soluble polyimine, 48.45 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 7.70 g of γ BL and 7.70 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Embodiment 9]

Using tetracarboxylic dianhydride component CBDA 26.67g (0.136 mol) and PMDA 13.09g (0.060 mol), diamine component 4-ABA 4.89g (0.040 mol), C12DAB 17.55g (0.060 mol), and 2,4 -DAA 20.33 g (0.100 mol), which was reacted at room temperature for 24 hours in NMP 330.10 g to obtain a polyaminic acid solution.

To 25.82 g of the polyamic acid solution, 37.6 g of NMP was added and diluted, and 3.73 g of acetic anhydride and 1.59 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 214.0 ml of methanol to recover a precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a yellow-white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 12,194 and a weight average molecular weight of 27,273. The yield of hydrazine was 94%.

To 2.76 g of the above-obtained soluble polyimine, 24.84 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 9.20 g of γ BL and 9.20 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Embodiment 10]

Using tetracarboxylic dianhydride component CBDA 18.36g (0.094 mol) and PMDA 5.23g (0.024 mol), diamine component C18DAB 4.52 (0.012 mol) and 2,4-DAA 21.96g (0.108 mol), in NMP 200.30 In g, the reaction was carried out at room temperature for 24 hours to obtain a polyaminic acid solution.

To 20.14 g of the polyamic acid solution, 29.18 g of NMP was added and diluted, and 2.88 g of acetic anhydride and 1.23 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 187.0 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a yellow-white powder of soluble polyimine. The soluble polyimine has a number average molecular weight of 12,941 and a weight average molecular weight of 30,624. The hydrazine imidation rate is 95%.

To 2.35 g of the above-obtained soluble polyimine, 21.15 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 7.83 g of γ BL and 7.83 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Example 11]

Using tetracarboxylic dianhydride component TDA 15.02g (0.050 mol) and PMDA 10.69g (0.049 mol), diamine component 2,4-DAA 20.33g (0.100 mol), in NMP 184.10g, at room temperature After reacting for 24 hours, a polyaminic acid solution was obtained.

To 14.80 g of the polyamic acid solution, 23.35 g of NMP was added and diluted, and 2.02 g of acetic anhydride and 0.86 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 143.6 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a yellow-white powder of soluble polyimine. Such a soluble polyimine has a number average molecular weight of 12,666 and a weight average molecular weight of 25,378. The hydrazine imidation rate was 94%.

To 1.91 g of the above-obtained soluble polyimine, 17.19 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 6.37 g of γ BL and 6.37 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Embodiment 12]

Using tetracarboxylic dianhydride component BODA 12.51g (0.050 mol) and PMDA 10.25g (0.047 mol), diamine component 2,4-DAA 20.33g (0.100 mol), in NMP 169.70g, at room temperature After reacting for 24 hours, a polyaminic acid solution was obtained.

To 13.30 g of the polyamic acid solution, 15.13 g of NMP was added and diluted, and 2.02 g of acetic anhydride and 0.86 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 109.6 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a yellow-white powder of soluble polyimine. The soluble polyimine had a number average molecular weight of 11,727 and a weight average molecular weight of 26,165. The hydrazine imidation rate was 49%.

To 1.82 g of the above-obtained soluble polyimine, 16.38 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 6.07 g of γ BL and 6.07 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

[Example 13]

Using tetracarboxylic dianhydride component CBDA 17.34g (0.088 mol) and PMDA 8.51g (0.039 mol), diamine component 3-ABA 6.35g (0.052 mol), C14DAB 12.50g (0.0.39 mol) and 2, 4-DAA 7.93 g (0.039 mol) was reacted at room temperature for 24 hours in NMP 263.11 g to obtain a polyaminic acid solution.

To 20.06 g of the polyamic acid solution, 34.7 g of NMP was added and diluted, and 2.89 g of acetic anhydride and 1.23 g of pyridine were added, and the mixture was reacted at 50 ° C for 3 hours to carry out hydrazine imidization.

After the reaction solution was cooled to room temperature, it was poured into 206.0 ml of methanol to recover the precipitated solid. Further, the solid matter was washed with methanol several times, and then dried under reduced pressure at 100 ° C to obtain a yellow-white powder of soluble polyimine. The soluble polyimine has a number average molecular weight of 9,442 and a weight average molecular weight of 24,660. The hydrazine imidation rate is 90%.

To 1.55 g of the above-obtained soluble polyimine, 13.95 g of γ BL was added, and the mixture was stirred at 50 ° C for 24 hours. The soluble polyimine was completely dissolved at the end of the agitation. After the solution was cooled to room temperature, 5.11 g of γ BL and 5.17 g of DPM were added and stirred sufficiently as a solution of 6 wt% of soluble polyimine and 20 wt% of DPM to obtain a liquid crystal aligning agent of the present invention.

The evaluation of the polishing resistance was carried out in the same manner as in Example 1 using this liquid crystal aligning agent. However, the polishing conditions were as strong as in Example 3. As a result, no scratch or peeling of the film was observed on the liquid crystal alignment film.

<Voltage retention rate and evaluation of accumulated charge>

The liquid crystal aligning agent prepared in each of Examples 3 to 13 and the liquid crystal aligning agent prepared in Comparative Example 1 and Comparative Example 4 were evaluated by voltage holding ratio measurement of the liquid crystal element described below and residual DC measurement. .

The liquid crystal aligning agent was spin-coated on a glass substrate with a transparent electrode, dried on a hot plate at 80 ° C for 5 minutes, and then fired in a hot air circulating oven at 230 ° C for 30 minutes to form a film thickness of 100 nm. Coating film. This coating film surface is ground using a grinding device with a roller diameter of 120 mm, using a rayon cloth, grinding at a roller speed of 1,000 rpm, a roller speed of 50 mm/sec, and a press-in amount of 0.5 mm, thereby obtaining a substrate to which a liquid crystal alignment film is attached. .

Two substrates are prepared, and a 6 μm pitch spacer is disposed on one of the liquid crystal alignment films, and a sealant is printed thereon; and the liquid crystal alignment film of the other substrate is bonded to the polishing direction. , the sealant is hardened to make an empty component. In this empty element, a liquid crystal MLC-2003 (manufactured by Meruku, Japan) was injected by a vacuum injection method, and the injection port was closed, that is, the filament liquid crystal element was twisted.

On this twisted filament liquid crystal cell, a voltage of 4 V between 60 μs was applied at a temperature of 23 ° C, a voltage after 16.67 ms was measured, and a maintainable voltage was calculated as a voltage holding ratio. Further, the same measurement was carried out at 80 °C.

Further, the voltage holding ratio was measured by using a VHR-1 voltage holding ratio measuring device manufactured by Dongyang Technology Co., Ltd.

Next, a DC voltage of a rectangular wave of ±3 V/30 Hz was superposed on the liquid crystal element having a measured voltage holding ratio at a temperature of 23 ° C for 60 minutes, and the liquid crystal immediately after the DC voltage of 3 V was cut by an optical flicker elimination method. Residual DC voltage within the component.

The results of this evaluation are as follows.

From the above evaluation results, it was confirmed that the tetracarboxylic dianhydride component exhibits a good voltage holding ratio when it contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure; and contains an alicyclic structure or an aliphatic group. Both the tetracarboxylic dianhydride of the structure and the aromatic tetracarboxylic dianhydride can reduce the residual DC voltage.

[Industrial use]

The liquid crystal aligning agent of the present invention contains a soluble polyimine, and a liquid crystal alignment film which is less likely to cause scratches on the surface of the film or peeling of the film during polishing can be obtained. Therefore, the liquid crystal display element produced by using the liquid crystal alignment treatment agent of the present invention can be used as a highly reliable liquid crystal display device. Further, it is suitably used for various types of display elements such as a TN liquid crystal display element, an STN liquid crystal display element, a TFT liquid crystal display element, an OCB liquid crystal display element, and a lateral electric field type liquid crystal display element.

The entire disclosure of the specification, the scope of the application, and the abstract of the Japanese Patent Application No. 2005-152720, filed on May 25, 2005, is hereby incorporated by reference.

Claims (7)

A liquid crystal aligning treatment agent which is a liquid crystal aligning treatment agent for a liquid crystal alignment film which is subjected to firing and polishing treatment on a substrate coated with an electrode; and is characterized in that it contains a diamine component and a tetracarboxylic dianhydride component. The polyamic acid obtained by the ruthenium imidization is obtained, and the sulfhydryl imidization ratio of the soluble polyimine is 40% or more, and the diamine component contains the following general formula [1] The diamine shown, The liquid crystal aligning agent according to claim 1, wherein the diamine component contains 20 mol% or more of the diamine represented by the general formula [1]. The liquid crystal aligning agent according to claim 1 or 2, wherein the tetracarboxylic dianhydride component contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure. The liquid crystal aligning agent according to claim 1 or 2, wherein the tetracarboxylic dianhydride component contains a tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure, and an aromatic tetracarboxylic dianhydride. The liquid crystal directional treatment agent according to claim 1, wherein the soluble polyimine has a weight average molecular weight of 2,000 to 200,000. A liquid crystal alignment film obtained by applying the liquid crystal alignment treatment agent according to any one of the above claims 1 to 5 to a substrate on which an electrode is attached, and firing and polishing. A liquid crystal display element characterized by using a liquid crystal alignment film of claim 6 of the patent application.