TWI416227B - Liquid crystal alignment and transverse type liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a horizontal liquid crystal display element superior in residual image relaxing characteristics and a liquid crystal aligning agent therefor. <P>SOLUTION: The liquid crystal aligning agent for a horizontal electric field system liquid crystal display element contains a soluble polyimide, having an imide structure obtained by cyclodehydrating a polyamic acid prepared by making tetracarboxylic acid dianhydride react with diamine. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

Liquid crystal alignment agent and horizontal electric field type liquid crystal display element

The present invention relates to a horizontal electric field type liquid crystal display element and a liquid crystal alignment agent therefor. More specifically, it relates to a horizontal electric field type liquid crystal display element excellent in afterimage relaxation performance and a liquid crystal alignment agent therefor.

Conventionally, as a liquid crystal display element, there is known a TN type liquid crystal display element having a so-called TN type (twisted nematic) liquid crystal cell which forms polyamine, polyimine, etc. on the surface of a substrate on which a transparent conductive film is provided. The liquid crystal alignment film to be formed is a substrate for a liquid crystal display element, and two of the substrates are opposed to each other, and a nematic liquid crystal layer having positive dielectric anisotropy is formed in the gap, and a unit of a sandwich structure is formed, and a long axis of the liquid crystal molecules is formed. The substrate is continuously twisted 90 degrees from one substrate to another.

Further, an STN (Super Twisted Nematic) type liquid crystal display element and a vertical alignment type liquid crystal display element having higher contrast and less viewing angle dependency than the TN type liquid crystal display element have been developed. The STN type liquid crystal display element is used as a liquid crystal by mixing an optically active substance chiral reagent in a nematic liquid crystal, and a birefringence effect is produced by causing a long axis of liquid crystal molecules to be continuously twisted by 180 degrees or more between substrates. .

In addition, the development of new liquid crystal display elements has been active in recent years. As one of them, a horizontal electric field type liquid crystal display element has been proposed in which two electrodes for driving liquid crystals are arranged in a comb shape on one side of the substrate, resulting in parallel with the substrate surface. The electric field controls the liquid crystal molecules. This element is generally called an in-plane conversion type (IPS type) and is known to have excellent wide viewing angle performance. And recently, by using an optical compensation film, the wide viewing angle performance is further improved, and it has a remarkable feature of obtaining a wide viewing angle which is comparable to a cathode ray tube which has no tone inversion and tone change.

However, as a currently known polyaminic acid or a quinone imine polymer having a structure obtained by the dehydration ring closure, for example, a photo-alignment film proposed in Patent Document 1 or a method proposed in Patent Document 2 or Patent Document 3 is used. When a polyamic acid is used to form a liquid crystal display device of a horizontal electric field type, an afterimage is generated. Although the afterimage is moderated and eliminated after a certain period of time, the problem is that liquid crystal display elements are particularly deadly for liquid crystal displays of high image quality and large capacity display.

Patent Document 1: Japanese Laid-Open Patent Publication No. Hei. No. Hei. No. 2003-149.

SUMMARY OF THE INVENTION An object of the present invention is to provide a horizontal electric field type liquid crystal display element excellent in after-image relaxation performance in order to solve the above problems of the prior art.

Another object of the present invention is to provide a liquid crystal alignment agent which provides the above-described excellent performance in the lateral electric field type liquid crystal display device of the present invention.

Other objects and advantages of the present invention will be apparent from the following description.

According to the present invention, the above objects and advantages of the present invention are first achieved by a liquid crystal alignment agent for a liquid crystal display device of a lateral electric field type, characterized in that it is one comprising the following formula (1)

A liquid crystal alignment agent for a liquid crystal display device of a transversely electric field type of a soluble polyimide having a quinone imine structure. Here, R ¹ is a tetravalent organic group, and R ² is a divalent organic group, and the solubility is The polyimine is obtained by cyclization dehydration of polyphthalic acid obtained by reacting a tetracarboxylic dianhydride with a diamine, and the oxime imidization ratio is 60 to 95%, and the soluble polyimine is The content rate is 60% or more relative to the total polyimine.

Further, according to the present invention, the above objects and advantages of the present invention, and secondly, are achieved by a lateral electric field type liquid crystal display element characterized by having a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention.

One of the problems in the horizontal electric field type liquid crystal display element is that the generation of the afterimage during long-time driving causes deterioration in quality as a display element. According to the liquid crystal alignment agent of the present invention, when the liquid crystal alignment film is formed, the problem is solved because the afterimage relaxation property is excellent. Therefore, the liquid crystal display element having the alignment film formed by the liquid crystal alignment agent of the present invention can be effectively used for various devices, for example, for desktop computers, watches, and the like, by obtaining a liquid crystal alignment film suitable for a liquid crystal display device of a lateral electric field type. Display devices such as clocks, counting displays, word processors, personal computers, portable phones, and LCD TVs.

Hereinafter, the present invention will be described in detail. The soluble polyimine used in the liquid crystal alignment agent for liquid crystal display elements of the transverse electric field type (hereinafter, simply referred to as "liquid crystal alignment agent of the present invention") of the present invention can preferably be made by using a tetracarboxylic dianhydride and a diamine compound. The polylysine obtained by the reaction in an organic solvent is partially cyclized and dehydrated. That is to say, the polyamidene having a ruthenium imidization ratio of polyamine is 60 to 95%. The resin solution obtained by dissolving the soluble polyimine and other polyimine in an organic polar solvent is applied onto a conventional glass substrate opposite to the glass substrate on which one surface of the ITO film is comb-shaped, and then dried and baked. A polyimide film is formed, and the surface of the film is subjected to an alignment treatment such as polishing, and used as a liquid crystal alignment film.

In the case of a horizontal electric field type liquid crystal display device, the problem of residual image generation is usually caused by driving an electric field for a long period of time. However, since the liquid crystal alignment agent of the present invention has excellent afterimage mitigating performance, the liquid crystal display element can be used as a horizontal electric field type. Give it excellent display performance.

In the synthesis of the polyamic acid used for the soluble polyimine of the present invention, as a specific example of the tetracarboxylic dianhydride used, pyromellitic dianhydride and 3-trifluoromethyl pyromellitic dianhydride may be mentioned. , benzophenone tetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4' -diphenyl ether tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid An aromatic tetracarboxylic dianhydride such as an anhydride; 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid An alicyclic tetracarboxylic dianhydride such as an anhydride or 2,3,5-tricarboxycyclopentyl acetic acid dianhydride. Among them, preferred are 2,3,5-tricarboxycyclopentyl acetic acid dianhydride and 1,2,3,4-cyclobutanetetracarboxylic dianhydride.

These tetracarboxylic dianhydrides can be used individually or in combination of 2 or more types. It is preferred to use 2,3,5-tricarboxycyclopentyl acetic acid dianhydride alone or preferably 20% by weight or more, more preferably 50% by weight or more with other tetracarboxylic dianhydrides. The mixture is used as a tetracarboxylic dianhydride.

Further, specific examples of the diamine used in the present invention include p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, and 4,4'-diaminobiphenyl. 2,2'-Dimethyl-4,4'-diaminobiphenyl, 2,2-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 4,4'-diamine Diphenyl ether, 1,5-diaminonaphthalene, 4,4'-diaminobenzophenone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 1 , an aromatic diamine such as 4-bis(4-aminophenoxy)benzene, 2,7-diaminopurine, 9,9-bis(4-aminophenyl)anthracene; butanediamine, pentane Aliphatic and alicyclic diamines such as amine, hexamethylenediamine, 1,4-diaminocyclohexane, tetrahydrodicyclopentadienyldiamine, 4,4'-methylenebis(cyclohexylamine) ; 2,3-diaminopyridine, 2,6-diaminopyridine, 2,4-diamino-6-dimethylamino-1,3,5-three 2,4-diamino-5-phenylthiazole, 3,5-diamino-1,2,4-triazole, bis(4-aminophenyl)phenylamine, etc. a primary amine and a diamine of a nitrogen atom other than the primary amine group, of which p-phenylenediamine, 4,4'-diaminodiphenylmethane and 4,4'-diaminodiphenyl ether are particularly preferred. 2,2-bis[4-(4-aminophenoxy)phenyl]propane and 2,2'-dimethyl-4,4'-diaminobiphenyl. Further, these diamine compounds may be used singly or in combination of two or more kinds. And these examples are not intended to limit the scope of the invention.

[Synthesis of polyglycine]

The use ratio of the tetracarboxylic dianhydride to the diamine compound to be supplied to the polyaminic acid synthesis reaction is preferably 0.2 to the acid group of the tetracarboxylic dianhydride relative to the amine group contained in the equivalent of the diamine compound. The ratio of 2 equivalents is more preferably a ratio of 0.8 to 1.2 equivalents. The synthesis reaction of polylysine is preferably carried out in an organic solvent at a temperature of from -20 to 150 ° C, more preferably from 0 to 100 ° C.

Here, the organic solvent is not particularly limited as long as it can dissolve the synthesized polyamic acid. For example, 1-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl hydrazine, γ-butyrolactone, tetramethylurea may be mentioned. An aprotic polar solvent such as trimethylamine hexamethylphosphite; a phenolic solvent such as m-methylphenol, xylenol, phenol or halogenated phenol. Further, the amount (α) of the organic solvent is preferably such an amount that the total amount (β) of the tetracarboxylic dianhydride and the diamine compound is from 0.1 to 30% by weight based on the total amount (α + β) of the reaction solution.

Further, in the range in which the produced polyaminic acid is not precipitated, a polyglycine poor solvent alcohol, a ketone, an ester, an ether, a halogenated hydrocarbon, a hydrocarbon, or the like may be used in combination in the above organic solvent. . Specific examples of such a poor solvent include methanol, ethanol, isopropanol, cyclohexanol, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol, propylene glycol, and 1,4-butane. Alcohol, triethylene glycol, ethylene glycol monomethyl ether, ethyl lactate, butyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, acetic acid Ester, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate, diethyl ether, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol n-propyl ether, B Glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diglyme, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, digan Alcohol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane Alkane, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, and the like.

As described above, a reaction solution in which polylysine was dissolved was obtained. Then, the reaction solution was poured into a large amount of poor solvent to obtain a precipitate. The polyamine acid is obtained by drying the precipitate under reduced pressure. Further, the polylysine is again dissolved in an organic solvent, and then precipitated with a poor solvent, and the polyamic acid can be purified by performing one or several steps.

[Synthesis of Polyimine]

The soluble polyimine which constitutes the liquid crystal alignment agent of the present invention can be synthesized by the above-mentioned polyamine dehydration ring closure. The polyimine used in the present invention has a quinone imine structure represented by the formula (1).

Here, R ¹ is a tetravalent organic group, and R ² is a divalent organic group.

In the above formula (1), the tetravalent organic group of R ¹ corresponds to a residue in which two acid anhydride groups are removed by tetracarboxylic dianhydride, and the divalent organic group of R ² corresponds to a diamine compound to remove two amines. The residue of the base.

The polyimine of the present invention may further contain the above quinone imine structure having a ruthenium iodide ratio of less than 100%. That is, it may also be a product in which the ruthenium acid structure is partially dehydrated and closed. Here, the "rhodium imidization ratio" means a ratio of a ratio of repeating units having a quinone ring or an isoindole ring in a total of a quinone imine repeating unit and a hydrazine repeating unit of a polymer. . Preferably, the imidization ratio is from 60 to 95%, more preferably from 80 to 95%. Dehydration ring closure of polylysine by (i) heating poly-proline, or (ii) dissolving poly-proline in an organic solvent, adding a dehydrating agent and a dehydration ring-closing catalyst to the solution and heating as needed The method went smoothly.

The reaction temperature in the above (i) heating of the polyamic acid is preferably from 50 to 200 ° C, more preferably from 60 to 170 ° C. When the reaction temperature is less than 50 ° C, the dehydration ring-closure reaction is difficult to complete, and if the reaction temperature exceeds 200 ° C, the molecular weight of the obtained polyimine may decrease.

On the other hand, in the above method (ii) in which a dehydrating agent and a dehydration ring-closing catalyst are added to a polyamic acid solution, an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent is preferably from 0.01 to 20 moles per 1 mole of the polyamido acid repeating unit, depending on the desired oxime imidization ratio. Further, as the dehydration ring-closure catalyst, a tertiary amine such as pyridine, trimethylpyridine, lutidine or triethylamine can be used. However, it is not limited to these. The amount of the dehydration ring-closing catalyst is preferably from 0.01 to 10 mols per mol of the dehydrating agent used. The larger the amount of the above dehydrating agent and the dehydration ring-closing catalyst, the higher the yield of ruthenium. The ruthenium imidation ratio is preferably from 40 to 100%, more preferably from 70 to 100%, from the viewpoint of the afterimage relaxation time of the liquid crystal display element. In addition, examples of the organic solvent used in the dehydration ring-closure reaction include the same solvents as those exemplified as the solvent used in the synthesis of polylysine. Further, the reaction temperature of the dehydration ring closure reaction is preferably from 0 to 180 ° C, more preferably from 10 to 150 ° C. Further, the polyimine can be purified by performing the same operation as in the polyamic acid purification method on the reaction solution thus obtained.

[Logarithmic Viscosity of Polymer]

The logarithmic viscosity (ηln) value of the polylysine and/or polyimine obtained as above is preferably from 0.05 to 10 dl/g, more preferably from 0.05 to 5 dl/g.

The logarithmic viscosity (ηln) value of the present invention is obtained by measuring the viscosity of a solution having a concentration of 0.5 g/100 ml at 30 ° C by using N-methyl-2-pyrrolidone as a solvent, and the value obtained by the following formula (I) .

[Other polyimine]

In the present invention, other polyimines other than the soluble polyimine may be used. Other polyimines refer to polyimines which are poorly soluble in organic solvents alone. Since the polyimine is preferably dissolved in the organic solvent in the liquid crystal alignment agent, the other polyimine must be 40% or less of the total polyimine.

The tetracarboxylic dianhydride and the diamine used for the synthesis of other polyimines can be used for synthesizing soluble polyimine. Further, the synthesis of other polyimines can also be carried out in the same manner.

[Liquid alignment agent]

The liquid crystal alignment agent of the present invention is preferably composed of polylysine and/or polyimine dissolved in an organic solvent. The temperature at which the liquid crystal alignment agent of the present invention is prepared is preferably from 0 ° C to 200 ° C, more preferably from 20 ° C to 60 ° C.

The organic solvent constituting the liquid crystal alignment agent of the present invention may, for example, be N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butylide, N,N-dimethylformamide, N,N. - dimethylacetamide, 4-hydroxy 4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethoxypropyl propionate Ester, ethylene glycol methyl ether, ethylene glycol ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl Ether acetate, diglyme, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, etc. .

The solid content concentration in the liquid crystal alignment agent of the present invention is selected in consideration of viscosity and volatility, and is preferably from 1 to 10% by weight. In other words, the liquid crystal alignment agent of the present invention is applied to the surface of the substrate to form a resin film as a liquid crystal alignment film. When the solid content concentration is less than 1% by weight, the thickness of the coating film is too small, and a satisfactory liquid crystal alignment film cannot be obtained. When the solid content concentration exceeds 10% by weight, the thickness of the coating film is too thick, a good liquid crystal alignment film cannot be obtained, and the viscosity of the liquid crystal alignment agent increases, and the coating property is deteriorated.

The liquid crystal alignment agent of the present invention may optionally contain a functional decane compound or an epoxy compound from the viewpoint of improving adhesion to the surface of the substrate within a range not impairing the physical properties of the object. Examples of such a functional decane compound include 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, and 2-amino group. Propyltriethoxydecane, N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldi Methoxydecane, 3-ureidopropyltrimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-ethoxycarbonyl 3-aminopropyltriethoxydecane, N-triethoxydecylpropyltriethylenetriamine, N-trimethoxydecylpropyltriethylenetriamine, 10-trimethoxydecane -1,4,7-triazadecane, 10-triethoxydecyl-1,4,7-triazadecane, 9-trimethoxyanthracene Alkyl-3,6-diazaindolyl acetate, 9-triethoxydecyl-3,6-diazaindolyl acetate, N-benzyl-3-aminopropyltrimethyl Oxydecane, N-benzyl-3-aminopropyltriethoxydecane, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltriethyl Oxydecane, N-bis(hydroxyethyl)-3-aminopropyltrimethoxydecane, N-bis(hydroxyethyl)-3-aminopropyltriethoxydecane, and the like. Examples of such an epoxy compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and neopentyl Alcohol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl Base-2,4-hexanediol, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl) Cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3-(N-allyl-N-glycidyl)amine Propyltrimethoxydecane, 3-(N,N-diglycidyl)aminopropyltrimethoxydecane, and the like.

[Liquid Crystal Display Element]

The lateral electric field type liquid crystal display element of the present invention can be produced, for example, by the following method.

(1) On one side of the conductive film forming surface of the substrate provided with the transparent conductive film forming the comb pattern and the opposite substrate on which the conductive film is not provided, for example, by a roll coater method, a spin coater method, or a printing method The liquid crystal alignment agent of the present invention is applied by a method, and then, a resin film is formed by heating the coated surface. Here, as the substrate, for example, glass such as float glass or soda lime glass; a transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether oxime or polycarbonate can be used. As the transparent conductive film provided on one side of the substrate, a NESA film made of tin oxide (SnO ₂ ) (registered trademark of PPG, USA), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), or the like can be used. . These transparent conductive film patterns are formed by photolithography and a method of using a mask in advance. At the time of application of the liquid crystal alignment agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the resin film, a functional decane-containing compound or a functional titanium-containing compound or the like may be applied to the surface of the substrate in advance. The heating temperature after the application of the liquid crystal alignment agent is preferably from 80 to 300 ° C, more preferably from 120 to 250 ° C. Further, in the liquid crystal alignment agent of the present invention, the organic solvent is removed by coating to form a resin film as an alignment film. However, when the ruthenium imidization is not completely carried out, further heat-dehydration ring closure is performed to form further ruthenium imidization. Resin film. The thickness of the formed resin film is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

(2) The surface of the formed resin film is subjected to a rubbing treatment by rubbing a roll of a cloth made of a fiber such as nylon, rayon, or cotton in a certain direction. Thus, a liquid crystal alignment film which imparts alignment energy to liquid crystal molecules to the resin film is prepared.

In addition, the liquid crystal alignment film formed by the liquid crystal alignment agent of the present invention is subjected to a process of changing the pretilt angle by partially irradiating ultraviolet rays as shown in Japanese Laid-Open Patent Publication No. Hei. 6-222366, No. Hei 6-281937. Alternatively, a protective film is partially formed on the surface of the liquid crystal alignment film subjected to the rubbing treatment as shown in JP-A-5-107544, and the protective film is removed in a direction different from the previous polishing treatment to remove the protective film. The process in which the liquid crystal alignment of the alignment film can be changed can improve the field of view characteristics of the liquid crystal display element.

(3) Each of the substrate on which the transparent conductive film is formed and the substrate on which the transparent conductive film pattern is not formed are fabricated one by one, and the rubbing directions in the respective liquid crystal alignment films are reversed in parallel, and the two substrates are placed oppositely through the gap (cell gap), two The peripheral portion of the substrate is bonded with a sealant, and the liquid crystal is injected into the cell gap divided by the surface of the substrate and the sealant to close the injection hole to form a liquid crystal cell. Then, a polarizing plate is bonded to the outer surface of the liquid crystal cell, that is, the other side surface of each of the substrates constituting the liquid crystal cell, so that the polarization direction thereof coincides with the rubbing direction of the liquid crystal alignment film formed on one side of the substrate, thereby obtaining a transverse electric field mode. Liquid crystal display element.

Here, as the sealant, for example, an alumina ball-containing epoxy resin or the like as a curing agent and a separator can be used.

The liquid crystal may be a nematic liquid crystal or a dish-shaped liquid crystal. Among them, a nematic liquid crystal is preferable, and for example, a Schiff base liquid crystal, an oxidized azo liquid crystal, a biphenyl liquid crystal, or a phenyl cyclohexane liquid crystal can be used. And an ester liquid crystal, a terphenyl liquid crystal, a biphenyl cyclohexane liquid crystal, a pyrimidine liquid crystal, a dioxane liquid crystal, a bicyclooctane liquid crystal, a cubic liquid crystal, or the like.

In addition, as the polarizing plate to be bonded to the outer surface of the liquid crystal cell, a polarizing plate or an H film which is obtained by sandwiching a polarizing film called an H film obtained by stretching a polyvinyl alcohol and simultaneously absorbing iodine, is sandwiched between the cellulose acetate protective film. A polarizing plate made by itself.

The invention will be more specifically illustrated by the following examples, but the invention is not limited thereto.

Among them, various measurements of the examples and comparative examples were carried out by the following methods.

(1) The alignment of the liquid crystal is applied to the liquid crystal display element using the obtained coating film as a liquid crystal alignment film. When the cutting (application/release) was performed, the presence or absence of an abnormal region was observed under a polarizing microscope, and when there was no abnormal region, it was evaluated as "good".

(2) Residual image relaxation measurement In a high-temperature environment (60 ° C), the liquid crystal display element is driven by an AC30V, 10 Hz triangular wave for 3 hours, and then the driving condition is changed to a rectangular wave of AC1V and 10 Hz at room temperature, until the residual wave The time required for disappearing was evaluated by measuring at a pitch of 1 second.

Synthesis Example 1 (Synthesis of Polymer)

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, and 4,4'-diaminodiphenylmethane 19.8 g as a diamine compound 0.1 mol was dissolved in 800 g of N-methyl-2-pyrrolidone and reacted at 60 ° C for 4 hours. Next, the reaction solution was poured into a large excess of methanol to precipitate a reaction product, which was then washed with methanol, and dried at 40 ° C for 15 hours under reduced pressure to obtain 390 g of polylysine having a logarithmic viscosity of 0.32 dl/g. . 25 g of the obtained polyamic acid was dissolved in 475 g of N-methyl-2-pyrrolidone, and 39.5 g of pyridine and 30.6 g of acetic anhydride were added thereto, and the mixture was dehydrated and closed at 110 ° C for 4 hours to carry out the same precipitation, washing, and reduced pressure as described above. 19.5 g of a polyimine (A-1) having a logarithmic viscosity of 0.64 dl/g and a ruthenium iodide ratio of 92% was obtained.

Synthesis Example 2 (Synthesis of Polymer)

In the same manner as in Synthesis Example 1, except that 10.8 g (0.1 mol) of p-phenylenediamine was used as the diamine compound in Synthesis Example 1, polylysine was obtained. Further, in the same manner as in Synthesis Example 1, the oxime imidization reaction was carried out to obtain 17.9 g of a polyimine (A-2) having a logarithmic viscosity of 0.77 dl/g and a ruthenium iodide ratio of 93%.

Synthesis Example 3 (Synthesis of Polymer)

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, and 4,4'-diaminodiphenylmethane 19.8 g as a diamine compound 0.1 mol was dissolved in 800 g of N-methyl-2-pyrrolidone and reacted at 60 ° C for 4 hours. Next, the reaction solution was poured into a large excess of methanol to precipitate a reaction product, which was then washed with methanol, and dried at 40 ° C for 15 hours under reduced pressure to obtain 390 g of polylysine having a logarithmic viscosity of 0.32 dl/g. . 25 g of the obtained polylysine was dissolved in 475 g of N-methyl-2-pyrrolidone, and 15.8 g of pyridine and 20.4 g of acetic anhydride were added thereto, and the mixture was dehydrated and closed at 110 ° C for 4 hours, and the same precipitation, washing, and reduced pressure were carried out. 18.5 g of a polyimine (A-3) having a logarithmic viscosity of 0.40 dl/g and a ruthenium iodide ratio of 81% was obtained.

Synthesis Example 4 (Synthesis of Polymer)

In the same manner as in Synthesis Example 1, except that 10.8 g (0.1 mol) of p-phenylenediamine was used as the diamine compound in Synthesis Example 1, polylysine was obtained. Further, in the same manner as in Synthesis Example 1, the ruthenium imidization reaction was carried out to obtain 16.8 g of a polyimine (A-4) having a logarithmic viscosity of 0.43 dl/g and a ruthenium iodide ratio of 83%.

Synthesis Example 5 (Synthesis of Polymer)

In the same manner as in Synthesis Example 1, except that 21.2 g (0.1 mol) of 2,2'-dimethyl-4,4'-diaminobiphenyl was used as the diamine compound in Synthesis Example 1, polyfluorene was obtained. Amino acid. Further, in the same manner as in Synthesis Example 1, the oxime imidization reaction was carried out to obtain 16.8 g of a polyimine (A-5) having a logarithmic viscosity of 0.43 dl/g and a ruthenium iodide ratio of 83%.

Synthesis Example 6 (Synthesis of Polymer)

In Synthesis Example 1, the same procedure as in Synthesis Example 1 was carried out except that 5.4 g (0.05 mol) of p-phenylenediamine and 9.9 g (0.05 mol) of 4,4'-diaminodiphenylmethane were used as the diamine compound. The operation was carried out to obtain polylysine. Further, in the same manner as in Synthesis Example 1, the oxime imidization reaction was carried out to obtain 18.0 g of a polyimine (A-6) having a logarithmic viscosity of 0.24 dl/g and a ruthenium iodide ratio of 81%.

Synthesis Example 7 (Synthesis of Polymer)

In the same manner as in Synthesis Example 1, except that 20.0 g (0.1 mol) of 4,4'-diaminodiphenyl ether was used as the diamine compound in Synthesis Example 1, polylysine was obtained. Further, in the same manner as in Synthesis Example 1, the oxime imidization reaction was carried out to obtain 19.6 g of a polyimine (A-7) having a logarithmic viscosity of 0.25 dl/g and a ruthenium iodide ratio of 80%.

Synthesis Example 8 (synthesis of polymer)

In Synthesis Example 1, except that 16.8 g (0.075 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride and 5.5 g (0.025 mol) of pyromellitic dianhydride were used as the tetracarboxylic dianhydride, The polyamino acid was obtained in the same manner as in Synthesis Example 1. Further, in the same manner as in Synthesis Example 1, the oxime imidization reaction was carried out to obtain 19.1 g of a polyimine (A-8) having a logarithmic viscosity of 0.28 dl/g and a ruthenium iodide ratio of 81%.

Synthesis Example 9 (synthesis of polymer)

7.2 g (0.0375 mol) of pyromellitic dianhydride as tetracarboxylic dianhydride and 8.0 g (0.0375 mol) of cyclobutane tetracarboxylic dianhydride, 4,4'-diamine as diamine compound 14.8 g (0.075 mol) of diphenylmethane was dissolved in 170 g of N-methyl-2-pyrrolidone and reacted at 60 ° C for 4 hours. Next, the reaction solution was poured into a large excess of methanol to precipitate a reaction product, which was then washed with methanol, and dried at 40 ° C for 15 hours under reduced pressure to obtain 21.5 g of a polyamine having a logarithmic viscosity of 0.16 dl/g. Acid (B-1).

Synthesis Example 10 (Synthesis of Polymer)

In addition to 22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as the acid anhydride, 19.8 g (0.1 mol) of 4,4'-diaminodiphenylmethane as the diamine compound In the same manner as in Synthesis Example 7, 21.4 g of polyamic acid (B-2) having a logarithmic viscosity of 0.35 dl/g was obtained.

Synthesis Example 11 (Synthesis of Polymer)

In Synthesis Example 1, except that 27.4 g (0.14 mol) of cyclobutanetetracarboxylic dianhydride was used as the acid dianhydride, 32.5 g (0.14 mol) of 2,2'-dimethyl-4,4'-diamine. In the same manner as in Synthesis Example 7, except that the bisphenyl compound was used as the diamine compound, 22.1 g of polyamic acid (B-3) having a logarithmic viscosity of 0.24 dl/g was obtained.

Example 1

The polyimine (A-1) obtained in Synthesis Example 1 was dissolved in γ-butyrolactone, and 0.75 parts by weight of N-ethoxycarbonyl-3-aminopropyl was dissolved with respect to 100 parts by weight of the polymer. The solution was formed into a solution having a solid concentration of 4% by weight, and the solution was filtered through a filter having a pore size of 1 μm to prepare a film-forming composition of the present invention.

Then, the film-forming composition was applied onto a transparent conductive film made of an ITO film provided on one surface of a glass substrate having a thickness of 1 mm by a spin coater, and dried on a hot plate at 230 ° C for 10 minutes to form a film. A resin film having a thickness of 800 angstroms.

The formed resin film surface was subjected to a rubbing treatment using a sander having a roll of a nylon cloth to form a liquid crystal alignment film. Here, the polishing treatment conditions were a roller rotation speed of 1000 rpm, a segment moving speed of 25 mm/sec, and a pile press-in length of 0.4 mm (the substrate was referred to as "substrate A").

Similarly, the film-forming composition was applied onto a 1 mm-thick glass substrate by a spin coater, and dried on a hot plate at 230 ° C for 10 minutes to form a resin film having a film thickness of 800 Å.

The formed resin film surface was subjected to a rubbing treatment using a sander having a roll of a nylon cloth to form a liquid crystal alignment film. Here, the polishing treatment conditions were a roller rotation speed of 1000 rpm, a segment moving speed of 25 mm/sec, and a pile press-in length of 0.4 mm (the substrate was referred to as "substrate B").

Then, on the outer edges of the substrate A and the substrate B having the liquid crystal alignment film in the liquid crystal-immobilized substrate, an epoxy resin binder of alumina balls having a diameter of 5.5 μm is applied, and then each is made In the rubbing direction of the liquid crystal alignment film, the two substrates are opposed to each other through the gap, and the outer edge portions are joined and pressed to cure the adhesive. Next, a nematic liquid crystal (MLC-2042, manufactured by Meluk Corporation) was filled between a pair of substrates through a liquid crystal injection port, and then the liquid crystal injection port was closed with an acrylic photocurable adhesive on both sides of the substrate. The polarizing plate was bonded thereto to obtain a horizontal electric field type liquid crystal display device of the present invention.

The obtained liquid crystal display element was evaluated, and the alignment property was good, and even if it was a strong grinding condition, no spots were identified. Uneven and so on. Further, using these liquid crystal display elements, the afterimage relief was evaluated. In this evaluation, the afterimage relaxation time was expressed as ○ for 1 second or less, and × for more than 1 second, and the results are shown in Table 1.

Example 2

A coating film was formed and a liquid crystal display element was produced in the same manner as in Example 1 except that the polymer listed in Table 1 was used, and various evaluations were carried out. The results are shown in Table 1.

Example 3~8

A coating film was formed and a liquid crystal display element was produced in the same manner as in Example 1 except that the polymer listed in Table 1 was dissolved in γ-butyrolactone to prepare a solution having a solid concentration of 4% by weight. Conduct various evaluations. The results are shown in Table 1.

Example 9~11

In addition to using the polymers listed in Table 1, when formulating the film-forming composition, 5 parts by weight of N,N,N',N'-tetraglycidyl-4 was dissolved with respect to 100 parts by weight of the polymer. A 4'-diaminodiphenylmethane (having a molecular weight of about 400) was used in the same manner as in Example 1 except that an epoxy-based additive was used to form a coating film and a liquid crystal display element, and various evaluations were carried out. The results are shown in Table 1.

Comparative example 1~3

A coating film was formed and a liquid crystal display element was produced in the same manner as in Example 1 except that the polymer listed in Table 1 was dissolved in γ-butyrolactone to prepare a solution having a solid concentration of 4% by weight. Conduct various evaluations. The results are shown in Table 1.

Claims (5)

A liquid crystal alignment agent for a liquid crystal display device of a transverse electric field type, which comprises a poly-proline acid obtained by reacting a tetracarboxylic dianhydride with a diamine, and having a cyclization dehydration effect, and having the following formula (1) A liquid crystal alignment agent for a liquid crystal display device of a transversely electric field type, which is a soluble polyimine of a quinone imine structure, and a functional decane compound or an epoxy compound. (wherein R ¹ is one or more selected from the group consisting of pyromellitic dianhydride, 3-trifluoromethyl pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, 1, 4, 5, 8- Naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 4,4'-bis (3, Aromatic tetracarboxylic dianhydride such as 4-dicarboxyphenoxy)diphenylpropane dianhydride or 3,3',4,4'-biphenyltetracarboxylic dianhydride; 1,2,3,4-ring An alicyclic ring such as butane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride or 2,3,5-tricarboxycyclopentyl acetic acid dianhydride The tetracarboxylic dianhydride of the tetracarboxylic dianhydride removes the residue of two acid anhydride groups, and R ² is one or more selected from the group consisting of p-phenylenediamine, m-phenylenediamine, and 4,4'-diamine. Diphenylmethane, 4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4 , 4'-diaminobiphenyl, 4,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 4,4'-diaminobenzophenone, 2,2-dual [ 4-(4-Aminophenoxy)phenyl]propane, 1,4-bis(4-aminophenoxy)benzene, 2,7-diaminoguanidine, 9,9-bis(4-amine Phenyl) hydrazine, butanediamine, pentanediamine, hexamethylenediamine, 1,4-diaminocyclohexane, tetra Dicyclopentadiene diamine, 4,4'-methylene bis(cyclohexylamine), 2,3-diaminopyridine, 2,6-diaminopyridine, 2,4-diamino-6 -dimethylamino-1,3,5-three , 2,4-diamino-5-phenylthiazole, 3,5-diamino-1,2,4-triazole, bis(4-aminophenyl)phenylamine diamine compound removal 2 The residue of the amine group); the soluble polyamidiamine has a sulfhydrylation ratio of 60 to 95%, and the content of the soluble polyamidimide accounts for 60% or more of the total polyimine. A liquid crystal alignment agent for a liquid crystal display device of a transverse electric field type according to the first aspect of the invention, wherein the tetracarboxylic dianhydride is composed of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride. The liquid crystal alignment agent for a liquid crystal display device of a horizontal electric field type according to the first aspect of the invention, wherein the tetracarboxylic dianhydride is composed of two or more kinds of tetracarboxylic dianhydrides, and 2,3,5-tricarboxycyclopentyl group The acetic acid dianhydride accounts for 20% by weight or more of the total amount of the tetracarboxylic dianhydride. The liquid crystal alignment agent for a liquid crystal display device of a horizontal electric field type according to the first aspect of the invention, wherein the diamine component is selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'- Composition of diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane and 2,2'-dimethyl-4,4'-diaminobiphenyl At least one diamine compound in the group. A liquid crystal display device of a horizontal electric field type, which is characterized by comprising a liquid crystal alignment film obtained by the liquid crystal alignment agent according to any one of claims 1 to 4.