CN101042505A - Vertical liquid crystal aligning agent and vertical liquid crystal display - Google Patents

Abstract

The present invention provides a vertical liquid crystal aligning agent, which can reduce uneven liquid crystal orientation originating from an ODF method by improving liquid crystal wettability of a vertical liquid crystal aligning film, and can generate high voltage retention and low residual DC. The vertical liquid crystal alignment agent is made of a polymer, the polymer includes amic acid repeating units and imide repeating units, and the polymer originates from tetracarboxylic dianhydride or diamine compound groups At least one of them contains fluorine atoms.

Description

Vertical liquid crystal alignment agent and vertical liquid crystal display element

technical field

The present invention relates to a vertical alignment liquid crystal display element capable of reducing uneven dropping of liquid crystals and spots of liquid crystal fusion sites in a liquid crystal dropping method (ODF). More specifically, it relates to a vertical liquid crystal aligning agent capable of producing a vertical liquid crystal aligning film having a small residual voltage and a high voltage retention rate, and a vertical liquid crystal display element having the vertical liquid crystal aligning film.

Background technique

At present, as a liquid crystal display element, a TN type liquid crystal display element having a so-called TN type (Twisted Nematic) liquid crystal cell is known. The liquid crystal alignment film such as imine is used as the substrate of the liquid crystal display element, and the two substrates are arranged opposite to each other, and a nematic liquid crystal layer with positive dielectric anisotropy is formed in the gap to form a sandwich structure cell, and the liquid crystal molecules The long axis of the substrate is continuously twisted 90 degrees from one substrate to the other.

In addition, STN (Super Twisted Nematic) type liquid crystal display elements and vertical alignment type liquid crystal display elements have been developed, which have higher contrast ratio and less viewing angle dependence than TN type liquid crystal display elements. The STN-type liquid crystal display element is used as a liquid crystal by mixing an optically active material chiral agent in a nematic liquid crystal, and utilizes the birefringence generated by making the long axis of the liquid crystal molecule in a state of continuously twisting a span of more than 180 degrees between the substrates effect.

In addition, in recent years, the development of new liquid crystal display elements is also very active. As one of them, a transverse electric field type liquid crystal display element has been proposed. The electric field parallel to the substrate plane controls the liquid crystal molecules (see Patent Document 1). This element is generally called an in-plane switching type (IPS type), and is known to be excellent in wide viewing angle performance. And recently, the wide viewing angle performance has been further improved by using an optical compensation film, and it has the outstanding feature of obtaining a wide viewing angle comparable to a cathode ray tube without tone inversion and tone change.

As a new liquid crystal display element other than the above, the liquid crystal molecules with negative dielectric anisotropy vertically aligned on the substrate are called MVA (Multi domain Vertical Alignment) type or PVA (Patterned Vertical Alignment) type vertical alignment type liquid crystal display element has been put into practical application. These MVA-type or PVA-type liquid crystal display elements are not only excellent in viewing angle and contrast, but also do not need to be polished in the process of forming the liquid crystal alignment film, etc., and are also excellent in the manufacturing process. Upsizing.

Usually, in order to manufacture a liquid crystal display element, it is necessary to go through the process of filling liquid crystal into the gap (cell gap) between two substrates on which the liquid crystal aligning film is formed. The liquid crystal filling usually adopts the vacuum injection method of filling the liquid crystal between the substrates of the liquid crystal display element by using the pressure difference between the atmospheric pressure and the vacuum. Therefore, the manufacturing process takes a lot of time, which becomes a big problem for extra-large panels.

In order to solve the above-mentioned problems in the vacuum injection method due to the increase in the size of the substrate in recent years, a liquid crystal dropping method (ODF method) has been developed. It is to drop a necessary amount of liquid crystal on the substrate forming the liquid crystal alignment film, make it bonded to another substrate under vacuum, and then UV-cure the sealant that seals the liquid crystal, so that the entire panel can be filled with liquid crystal. method. However, in this method, since the liquid crystal is directly dropped on the liquid crystal alignment film, compared with the current vacuum injection method, the liquid crystal alignment film also needs to bear the dropping load, and there are many liquid crystal dropping points, so the liquid crystal dropping part and the liquid crystal Alignment unevenness occurs at fusion sites and the like between them, resulting in a problem that display defects occur in liquid crystal display elements. Generally, in order to vertically align liquid crystals in vertical liquid crystal alignment films, hydrophobic components must exist on the surface of the film, and because the interaction between hydrophobic components and liquid crystals is weak, the wettability of liquid crystals is very poor. As a result, it is considered that alignment unevenness occurs due to a large load applied when the liquid crystal is dropped or expanded. At present, for this shortcoming, attempts have been made to reduce the load on the liquid crystal alignment film and optimize the manufacturing process, such as reducing the amount of liquid crystal dropping, reducing the liquid crystal dropping pressure, etc., but with the further increase in the size of the substrate, the current manufacturing process prevents Display defects cannot be prevented, so it is necessary to improve the liquid crystal alignment film.

[Patent Document 1] Japanese Patent Application Laid-Open No. 7-261181

Contents of the invention

The object of this invention is to provide the vertical liquid crystal aligning agent which can reduce the liquid crystal orientation nonuniformity originating in the ODF system, and can produce high voltage holding ratio and low residual DC. Further other objects and advantages of the present invention can be understood from the following description.

technical means to solve problems

According to the present invention, the above-mentioned purposes and advantages of the present invention, the first, are achieved by a vertical alignment type liquid crystal aligning agent, characterized in that it comprises (i) an amic acid repeating unit represented by the following formula (I-1) and/or (ii) a polymer composed of imide repeating units represented by the following formula (I-2),

Wherein, P ¹ and Q ¹ are 4-valent and 2-valent organic groups respectively, and wherein at least one of P ¹ and Q ¹ is a group containing a fluorine atom;

Wherein, P ² and Q ² are tetravalent and divalent organic groups, respectively, and at least one of P ² and Q ² is a group containing a fluorine atom.

And according to the present invention, the above-mentioned objects and advantages of the present invention are secondly achieved by a vertical liquid crystal display element, which is characterized in that it has a vertical liquid crystal alignment film made of the above-mentioned vertical liquid crystal alignment agent.

The liquid crystal aligning film formed by the vertical liquid crystal aligning agent of the present invention can shorten the manufacturing process time and increase the output by liquid crystal dripping, so it is suitable for large substrates to obtain excellent liquid crystal display elements with the best cost-effectiveness ratio. In addition, since the vertical liquid crystal alignment film formed from the vertical liquid crystal alignment agent of the present invention has excellent electrical properties, it is suitable for constituting a liquid crystal display element.

The liquid crystal display device of the present invention can be effectively used in various devices, for example, it can be suitably used as display devices such as desktop calculators, watches, desk clocks, mobile phones, counter displays, word processors, personal computers, and liquid crystal televisions.

Detailed ways

Hereinafter, the present invention will be specifically described.

The vertical alignment type liquid crystal aligning agent of the present invention (hereinafter also referred to as "the liquid crystal aligning agent of the present invention") comprises the amic acid repeating unit represented by the above formula (I-1) and/or the amic acid represented by the above formula (I-2). A polymer composed of imide repeating units.

The polyamic acid which consists of the said polyamic-acid repeating unit can be manufactured by making a tetracarboxylic dianhydride and a diamine compound react in an organic solvent. The tetracarboxylic dianhydride used is classified into a polyamic acid containing a fluorine atom and a polyamic acid not containing a fluorine atom capable of producing ^P1 in formula (I-1).

[Tetracarboxylic dianhydride]

As the tetracarboxylic dianhydride not containing a fluorine atom, for example, butane tetracarboxylic dianhydride, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2-dimethyl-1 , 2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-diethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1 , 2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-diethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1, 2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3, 4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3',4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3 , 5-tricarboxycyclopentyl acetic anhydride, 1,2,4-tricarboxycyclopentyl acetic anhydride, 3,5,6-tricarboxynorbornane-2-acetic anhydride, 2,3,4 , 5-tetrahydrofuran tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2 -c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5-methyl-5-(tetrahydro-2,5-dioxo-3-furan base)-naphthalene[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5-ethyl-5-(tetrahydro-2,5 -Dioxo-3-furyl)-naphthalene[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-7-methyl-5 -(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexa Hydrogen-7-ethyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2-c]-furan-1,3-dione, 1,3,3a , 4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2-c]-furan-1,3- Diketone, 1,3,3a,4,5,9b-hexahydro-8-ethyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2-c ]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-5,8-dimethyl-5-(tetrahydro-2,5-dioxo-3- Furyl)-naphthalene[1,2-c]-furan-1,3-dione, 5-(2,5-dioxotetrahydrofuryl methylene)-3-methyl-3-cyclohexene-1 , 2-dicarboxylic dianhydride, bicyclo[2.2.2]-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, compounds represented by the following formulas (1) and (2), etc. Aliphatic and cycloaliphatic tetracarboxylic dianhydrides;

(wherein, R ⁸ and R ¹⁰ represent divalent organic groups with aromatic rings, R ⁹ and R ¹¹ represent hydrogen atoms or alkyl groups, and multiple R ⁹ and R ¹¹ can be the same or different);

Pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride, 1,4, 5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3' , 4,4'-Dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic Acid dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylsulfide dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylsulfone Dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-perfluoroisopropylidene diphthalic anhydride , 3,3',4,4'-biphenyltetracarboxylic dianhydride, bis(phthalic acid) phenylphosphine oxide dianhydride, p-phenylene-bis(triphenylphthalic acid) di Acid anhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenyl ether dianhydride, bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid) Dicarboxylic acid)-4,4'-diphenylmethane dianhydride, ethylene glycol-bis(dehydrated trimellitate), propylene glycol-bis(dehydrated trimellitate), 1,4-butanediol- Bis(anhydrotrimellitate), 1,6-hexanediol-bis(anhydrotrimellitate), 1,8-octanediol-bis(anhydrotrimellitate), 2,2- Aromatic tetracarboxylic dianhydrides such as bis(4-hydroxyphenyl)propane-bis(dehydrated trimellitate). These tetracarboxylic dianhydrides can be used individually by 1 type or in combination of 2 or more types.

Among these tetracarboxylic acid dianhydrides, it is preferred to be able to produce a quaternary organic group represented by the following formula (IV-1) as represented by the following formula ( ^IV ) of the amic acid repeating unit P represented by the above formula (I-1) Tetracarboxylic dianhydride,

Wherein, the definitions of R ¹ , R ² , R ³ , R ⁴ and R ⁵ are the same as those of the above formula (IV-1). As these preferred tetracarboxylic dianhydrides, for example, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutane tetra Carboxylic acid dianhydride, 1,2-diethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetra Carboxylic acid dianhydride, 1,3-diethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4- Cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic dianhydride, 1,2,4-tricarboxycyclopentyl acetic dianhydride, 1,2,3,4-cyclopentane Tetracarboxylic dianhydride, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2 , 5-dioxo-3-furyl)-naphthalene[1,2-c]-furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-ethyl -5-(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2-c]-furan-1,3-dione. Among them, 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,2,4-tricarboxycyclopentylacetic dianhydride, 1,3,3a , 4,5,9b-hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2-c]-furan-1,3- Diketone, 1,3,3a,4,5,9b-hexahydro-8-ethyl-5-(tetrahydro-2,5-dioxo-3-furyl)-naphthalene[1,2-c ]-furan-1,3-dione, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic dianhydride. The tetracarboxylic dianhydride represented by the above formula (IV) preferably contains 10 mol% or more based on the total tetracarboxylic dianhydride, more preferably 20 mol% or more, and still more preferably 40 mol% or more from the viewpoint of improving performance. And at this time, it is preferable to use an alicyclic tetracarboxylic dianhydride from the point which fully acquires the effect of the liquid crystal aligning agent of this invention as tetracarboxylic dianhydride other than the above.

On the other hand, as the tetracarboxylic dianhydride containing a fluorine atom, a tetracarboxylic dianhydride containing a fluorine atom represented by the following formula (II) is preferable,

Wherein, at least one of ^A1 and ^A2 , or at least one of ^A3 and ^A4 is a fluorine atom or a fluoroalkyl group, and the rest are hydrogen atoms or an alkyl group.

Such fluorine-containing tetracarboxylic dianhydrides include, for example, 2,2-bis(1,3-dioxo-1,3-dihydroisobenzofuran-6-yl)-1,1, 1,3,3,3-hexafluoropropane, 1-trifluoromethyl-2,3,5,6-benzenetetracarboxylic dianhydride and 1,4-bistrifluoromethyl-2,3,5, 6-Benzenetetracarboxylic dianhydride. From the viewpoint of sufficiently obtaining the effects of the present invention, it is preferable to use 1 to 50 mol % of fluorine-containing tetracarboxylic dianhydride based on the total amount of tetracarboxylic dianhydride, and it is more preferable to use 20 to 50 mol %.

[Diamine compound]

The diamine compound used can be classified into a fluorine atom-containing diamine compound capable of producing Q ¹ in formula (1-1) or a fluorine atom-free diamine compound. As diamine compounds not containing fluorine atoms, p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4, 4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzidine Anilide, 4,4'-diaminodiphenyl ether, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 5-amino-1-(4' -aminophenyl)-1,3,3-trimethylindane, 6-amino-1-(4'-aminophenyl)-1,3,3-trimethylindane, 3,4'- Diaminodiphenyl ether, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 4,4'-diaminobenzophenone, 2,2-bis[4-(4 -aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis[4-aminophenyl]hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]sulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene , 1,3-bis(3-aminophenoxy)benzene, 9,9-bis(4-aminophenyl)-10-hydroanthracene, 2,7-diaminofluorene, 9,9-bis(4- Aminophenyl)fluorene, 4,4'-methylene-bis(2-chloroaniline), 2,2',5,5'-tetrachloro-4,4'-diaminobiphenyl, 2,2'-Dichloro-4,4'-diamino-5,5'-dimethoxybiphenyl,3,3'-dimethoxy-4,4'-diaminobiphenyl,1,4,4' -(p-phenyleneisopropylidene)diphenylamine, 4,4'-(m-phenyleneisopropylidene)diphenylamine, 4-(4-n-heptylcyclohexyl)-phenoxy- Aromatic diamines such as 2,4-diaminobenzene;

1,1-m-xylylenediamine, 1,3-propylenediamine, butanediamine, pentamethylenediamine, hexamethylenediamine, heptanediamine, octyldiamine, nonanediamine, 4,4-diaminoheptanediamine Amine, 1,4-diaminocyclohexane, isophorone diamine, tetrahydrodicyclopentadiene diamine, hexahydro-4,7-methylene indene dimethylene diamine, tricyclo[6.2 .1.0 ^2,7 ]-undecenedimethyldiamine, 4,4'-methylenebis(cyclohexylamine) and other aliphatic and alicyclic diamines;

2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 5,6-diamino-2,3-dicyanopyrazine, 5 , 6-diamino-2,4-dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-triazine, 1,4-bis(3-aminopropyl)piperazine , 2,4-diamino-6-isopropoxy-1,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4- Diamino-6-phenyl-1,3,5-triazine, 2,4-diamino-6-methyl-s-triazine, 2,4-diamino-1,3,5-triazine, 4,6-diamino-2-vinyl-s-triazine, 2,4-diamino-5-phenylthiazole, 2,6-diaminopurine, 5,6-diamino-1,3-di Methyluracil, 3,5-diamino-1,2,4-triazole, 6,9-diamino-2-ethoxyacridine lactate, 3,8-diamino-6-phenyl Diamine compounds such as phenanthridine, 1,4-diaminopiperazine, 3,6-diaminoacridine, bis(4-aminophenyl)phenylamine; these diamine compounds can be used alone or in combination of two or more.

Among these diamine compounds, Q ¹ as the imide repeating unit represented by the above-mentioned formula (I-1) is preferably a diamine represented by the formulas (V ₁ ) and (V ₂ ),

Among them, ^R6 is a divalent organic group having an alicyclic skeleton with 4-40 carbon atoms, ^R7 is an alkyl group with 10-20 carbon atoms, an alicyclic group with 4-40 carbon atoms A monovalent organic group with a skeleton of the formula, X is a single bond, -O-, -CO-, -COO-, -OCO-, -NHCO-, -CONH-, -S-, methylene, and the number of carbon atoms is 2-6 alkylene and phenylene. Such preferable diamines include, for example, compounds represented by the following formulas (3) to (5) as diamine compounds represented by the formula (V ₁ ), and examples of diamine compounds represented by the formula (V ₂ ) include the following: Compounds represented by formulas (6) to (16).

The diamine compounds represented by the formulas (V ₁ ) and (V ₂ ) are preferably used in an amount of 10-60 mol % of all diamine compounds, more preferably in a range of 20-50 mol %.

On the other hand, as a diamine compound containing a fluorine atom, a diamine compound represented by the following formula (III) is preferable,

Wherein, at least one of ^A5 and ^A6 is a fluorine atom or a fluoroalkyl group, the rest are hydrogen atoms or an alkyl group, and ^A7 and ^A8 are hexafluoropropylene groups. Examples of such fluorine-containing diamine compounds include 4,4'-diamine-2,2'-bis(trifluoromethyl)biphenyl, 2,2-bis(4-aminophenyl)hexafluoropropane , 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl] Hexafluoropropane, 4,4-bis[(4-amino-2-trifluoromethyl)phenoxy]-octafluorobiphenyl.

Such a fluorine-containing diamine compound is preferably used in an amount of 1 to 60 mol%, more preferably in an amount of 10 to 40 mol%, based on all diamines.

The polymer having the imide repeating unit represented by the above formula (I-2) of the present invention can be produced by dehydrating and ring-closing a polyamic acid composed of the amic acid repeating unit represented by the above formula (I-1).

[Synthesis of polyamic acid]

The usage ratio of the tetracarboxylic dianhydride and diamine used in the synthesis reaction of polyamic acid is preferably such that the anhydride group of the tetracarboxylic dianhydride is 0.2 to 2.0 equivalents, more preferably 0.8, relative to 1 equivalent of the amino group of the diamine. ~1.2 equivalent ratio. The synthesis reaction of polyamic acid is preferably carried out in an organic solvent at a temperature of -20 to 150°C, more preferably at a temperature of 0 to 100°C.

Here, the organic solvent is not particularly limited as long as it can dissolve the synthesized polyamic acid, and examples include 1-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-di Methylformamide, dimethylsulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphoric triamide and other aprotic polar solvents; m-cresol, xylenol, phenol, halogenated phenol and other phenolic solvents. In addition, the usage-amount (α) of the organic solvent is preferably an amount such that the total amount (β) of the tetracarboxylic dianhydride and the diamine compound is 0.1 to 30% by weight relative to the total amount (α+β) of the reaction solution.

In addition, alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons, etc., which are poor solvents for polyamic acid, may be used in combination with the above-mentioned organic solvent within the range where the produced polyamic acid is not precipitated. Specific examples of such poor solvents include methanol, ethanol, isopropanol, cyclohexanol, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol, propylene glycol, 1,4-butanediol, Alcohol, triethylene glycol, ethylene glycol monomethyl ether, ethyl lactate, butyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate Ester, methyl methoxy propionate, ethyl ethoxy propionate, diethyl oxalate, diethyl malonate, diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethyl Diol 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, diethylene glycol Alcohol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane alkanes, chlorobenzene, o-dichlorobenzene, hexane, heptane, octane, benzene, toluene, xylene, etc.

As mentioned above, the reaction solution which melt|dissolved polyamic acid was obtained. Then, the reaction solution is poured into a large amount of poor solvent to obtain a precipitate, and the polyamic acid can be obtained by drying the precipitate under reduced pressure. Then, the polyamic acid can be purified by redissolving the polyamic acid in an organic solvent and then precipitating it with a poor solvent once or several times.

[Terminal modified polymer]

The polyamic acid polymer of the present invention may be an end-modified polymer whose molecular weight has been adjusted. By using this terminal modification type polymer, the application|coating characteristic of a liquid crystal aligning agent, etc. can be improved, without impairing the effect of this invention. Such an end-modified polymer can be synthesized by adding a monobasic acid anhydride, a monoamine compound, a monoisocyanate compound, etc. to the reaction system during the synthesis of polyamic acid. Among them, examples of monobasic acid anhydrides include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl succinic anhydride, n-hexadecyl Succinic anhydride, etc. In addition, examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, n- Dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n-eicosylamine, etc. Moreover, as a monoisocyanate compound, phenyl isocyanate, naphthyl isocyanate, etc. are mentioned, for example.

[Imidated Polymer]

The imidized polymer constituting the liquid crystal aligning agent of the present invention can be prepared by dehydrating and ring-closing the above polyamic acid. The dehydration and ring-closure of polyamic acid can be carried out by (i) heating polyamic acid, or (ii) dissolving polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring-closure catalyst to the solution and heating as required . The reaction temperature in the method of heating polyamic acid of said (i) is 50-300 degreeC normally, Preferably it is 120-250 degreeC. When the reaction temperature is lower than 50°C, the dehydration ring-closing reaction cannot proceed completely, and when the reaction temperature exceeds 200°C, the molecular weight of the obtained imidized polymer may decrease.

[logarithmic viscosity of polymer]

The logarithmic viscosity (ηln) of the polyamic acid and/or polyimide polymer obtained above is preferably 0.05-10 dl/g, more preferably 0.05-5 dl/g.

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

[Vertical Alignment Type Liquid Crystal Alignment Agent]

As the organic solvent constituting the liquid crystal aligning agent of the present invention, for example, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, N,N- Dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate , ethylene glycol methyl ether, ethylene glycol ethyl 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, Diethylene glycol dimethyl ether, 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 aligning agent of the present invention is selected in consideration of viscosity, volatility, etc., and is preferably in the range of 1 to 10% by weight. That is to say, the liquid crystal aligning agent of the present invention is coated on the substrate surface to form a resin film as a liquid crystal aligning film. When the solid content concentration is less than 1% by weight, the thickness of the resin film will be too small, thereby failing to obtain a good liquid crystal. Alignment film; when the solid content concentration exceeds 10% by weight, the thickness of the resin film will be too thick, so that a good liquid crystal alignment film cannot be obtained, and the viscosity of the liquid crystal alignment agent will increase and the coating properties will deteriorate.

The liquid crystal aligning agent of this invention may contain the compound which has a functional silane, or an epoxy compound within the range which does not impair the target physical property from a viewpoint of improving the adhesiveness to a board|substrate surface. Examples of compounds having such functional silanes include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltrimethoxysilane, Ethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3- Ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane Oxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-tri Azadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-tri Ethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-di(oxyethylene)-3-aminopropyltrimethoxysilane, N-bis(oxyethylene)-3-aminopropyltriethoxysilane and the like.

The mixing ratio of these functional silane-containing compounds is preferably 60 parts by weight or less, more preferably 50 parts by weight or less, based on 100 parts by weight of the total amount of the polyamic acid and/or imidized polymer.

Examples of epoxy compounds include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol Diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl -2,4-hexanediol, N,N,N',N'-tetraglycidyl-m-xylylenediamine, N,N,N',N'-tetraglycidyl-2,2' -Dimethyl-4,4'-diaminobiphenyl, N,N,N',N'-tetraglycidyl-4,4'-diaminobenzene, 1,3-di(N,N-di Glycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3-(N-allyl-N-glycidyl Glyceryl)aminopropyltrimethoxysilane, 3-(N,N-diglycidyl)aminopropyltrimethoxysilane, and the like. Particularly preferred examples include polyethylene glycol diglycidyl ether, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 1,3,5,6-tetraglycidyl Glycidyl-2,4-hexanediol, N,N,N',N'-tetraglycidyl-2,2'-dimethyl-4,4'-diaminobiphenyl, N,N, N',N'-tetraglycidyl-4,4'-diaminobenzene, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, etc.

The mixing ratio of these epoxy compounds is preferably 60 parts by weight or less, more preferably 5 to 50 parts by weight, based on 100 parts by weight of the total amount of the polyamic acid and/or imidized polymer.

[LCD display element]

The vertical liquid crystal display element of this invention can be manufactured by the following method, for example.

(1) By methods such as roll coater method, spin coater method, printing method, inkjet method, etc., liquid crystal aligning agent of the present invention is coated on the substrate one side that is provided with the transparent conductive film that forms pattern, then, by The coated surface is heated to form a coating film. Here, as the substrate, glass such as float glass and soda lime glass; transparent substrates made of plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, and polycarbonate can be used. . As the transparent conductive film provided on one side of the substrate, NESA film (registered trademark of PPG Corporation of the United States) made of tin oxide (SnO ₂ ), ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), etc. can be used. . These transparent conductive film patterns can be formed by photolithography or by using a mask in advance. In the application of the liquid crystal aligning agent, in order to further improve the adhesiveness between the substrate surface and the resin film, for example, a functional silane-containing compound, a functional titanium-containing compound, etc. may be applied in advance. It is preferable that the heating temperature after coating a liquid crystal aligning agent is 80-300 degreeC, More preferably, it is 120-250 degreeC. In addition, the liquid crystal aligning agent of the present invention removes the organic solvent after coating to form a resin film as an alignment film, and when the imidization is not completely carried out, it can also be dehydrated and ring-closed by further heating to form a further imidized resin film. The thickness of the formed resin film is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm. And the formed vertical liquid crystal alignment film can also use the technology shown in JP-A-2002-327058 to form a structure on the substrate with a photosensitive resin, and then form the vertical liquid crystal alignment film according to the above-mentioned method on the substrate on which the above-mentioned structure is formed. Liquid crystal alignment film.

(2) Manufacture 2 substrates on which the vertical liquid crystal alignment film is formed as described above, and arrange the 2 substrates oppositely through the gap (cell gap), and bond the peripheral parts of the 2 substrates with a sealant, to the surface of the substrate and the sealant Liquid crystal is filled in the cell gap separated by the agent, and the injection hole is closed to form a liquid crystal cell. Then, a polarizing plate was disposed on the outer surface of the liquid crystal cell, that is, on the side of the transparent substrate constituting the liquid crystal cell, to obtain a liquid crystal display element.

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

Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals. Among them, nematic liquid crystals are preferable, and for example, Schiff's base liquid crystals, azoxy-based liquid crystals, biphenyl liquid crystals, phenylcyclohexane liquid crystals, ester liquid crystals, terphenyl liquid crystals, biphenyl ring liquid crystals, etc., can be used. Hexane-based liquid crystals, pyrimidine-based liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, cubane-based liquid crystals, etc. In addition, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl pelargonate, and cholesteryl carbonate may be added to these liquid crystals; available chiral reagents and the like. Furthermore, ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate can also be used.

In addition, examples of the polarizing plate to be bonded to the outer surface of the liquid crystal cell include a polarizing film obtained by stretching and aligning polyvinyl alcohol while absorbing iodine. Polarizer made of H film itself.

【Example】

The present invention will be described more specifically by way of examples below, but the present invention is not limited to these examples.

In addition, various measurements in Examples and Comparative Examples were performed according to the following methods.

(1) Evaluation of liquid crystal wettability

After dropping a liquid crystal (MLC-2038 produced by Melk Corporation) on a substrate coated with an alignment film (film thickness 80 nm), when the contact angle between the liquid crystal and the alignment film was measured, those with a contact angle of 15 degrees or less were evaluated as having good wettability.

(2) Determination of voltage retention rate

At 60°C, a voltage of 5V was applied to the liquid crystal display element, the voltage application time was 60 microseconds, and after the application time span was 167 microseconds, the voltage retention rate was measured from the voltage release to 167 milliseconds.

(3) Determination of residual voltage

At an ambient temperature of 100°C, a DC voltage of 17.0V was applied to the liquid crystal display element for 20 hours, and immediately after the DC voltage was cut off, it was left to cool at room temperature for 15 minutes, and the residual voltage in the liquid crystal cell was obtained by the flicker-elimination method. At this time, when the residual voltage was 800 mV or less, it was evaluated as good.

(4) Confirmation of Vertical Orientation

The state of the vertical alignment type liquid crystal display element when the voltage was off and an AC voltage of 4 V was applied was visually observed, and it was evaluated as good when there was no light leakage and poor alignment.

Synthesis example 1 (synthesis of polyamic acid)

13.1 g (0.06 mol) of 2,3,5,6-benzenetetracarboxylic dianhydride as tetracarboxylic dianhydride and 9.0 g (0.04 mol) of 2,3,5-tricarboxycyclopentylacetic dianhydride, 3.2 g (0.03 mol) of p-phenylenediamine as a diamine compound, 9.6 g (0.03 mol) of 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl and the above formula (7 ) 20.9 g (0.04 mol) of the compound represented was dissolved in 185 g of N-methyl-2-pyrrolidone and reacted at 40° C. for 4 hours. Next, the reaction solution was poured into a large excess of methanol to precipitate the reaction product. Then, it was washed with methanol, and dried at 40° C. under reduced pressure for 15 hours to obtain 32.9 g of a polyamic acid having a logarithmic viscosity of 1.21 dl/g (this was referred to as “polyamic acid (PA-1)”).

Synthesis example 2 (synthesis of polyamic acid)

In addition to using 19.2 g (0.06 mol) of 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl and 20.9 g (0.04 mol) of the compound represented by the above formula (7) as the diamine compound , in the same manner as in Synthesis Example 1, 59.1 g of a polyamic acid having a logarithmic viscosity of 1.16 dl/g (this is referred to as "polyamic acid (PA-2)") was obtained.

Synthesis example 3 (synthesis of polyamic acid)

In addition to using 4.9 g (0.045 mol) of p-phenylenediamine, 4.8 g (0.015 mol) of 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl and 20.9 g (0.04 mol) of the above Except that the compound represented by the formula (7) was used as a diamine compound, the same procedure as in Synthesis Example 1 was carried out to obtain 49.9 g of a polyamic acid having a logarithmic viscosity of 1.31 dl/g (this was referred to as "polyamic acid (PA-3)") .

Synthesis example 4 (synthesis of polyamic acid)

In addition to using 4.3g (0.04 moles) of p-phenylenediamine, 10.0g (0.03 moles) of 2,2-bis(4-aminophenyl)hexafluoropropane and 15.7g (0.03 moles) of the compound represented by the above formula (7) Except for the diamine compound, it carried out similarly to the synthesis example 1, and obtained 48.5 g of polyamic acids (this is called "polyamic acid (PA-4)") whose logarithmic viscosity was 1.02 dl/g.

Synthesis example 5 (synthesis of polyamic acid)

In addition to using 6.4 g (0.03 mol) of 2,2'-dimethyl-4,4'-diaminobiphenyl, 12.8 g (0.04 mol) of 4,4'-diamino-2,2'-bis(trifluoro Methyl) biphenyl and 15.7g (0.03 moles) the compound that above-mentioned formula (7) represents is as diamine compound, operate in the same way as Synthetic Example 1, obtain 42.2g logarithmic viscosity and be the polyamic acid of 1.11dl/g ( It is referred to as "polyamic acid (PA-5)").

Synthesis example 6 (synthesis of polyamic acid)

In addition to using 8.5 g (0.04 mol) of 2,2'-dimethyl-4,4'-diaminobiphenyl, 10.0 g (0.03 mol) of 2,2-bis(4-aminophenyl)hexafluoropropane and 15.7 g (0.03 moles) of the compound represented by the above-mentioned formula (7) was used as a diamine compound, and the same operation was performed as in Synthesis Example 1 to obtain 51.7 g of a polyamic acid having a logarithmic viscosity of 1.09 dl/g (which was referred to as "polyamic acid ( PA-6)").

Synthesis example 7 (synthesis of polyamic acid)

In addition to using 13.1g (0.06mol) of 2,3,5,6-benzenetetracarboxylic dianhydride and 7.8g (0.04mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic Except for acid anhydride, it carried out similarly to the synthesis example 1, and obtained 30.4 g of polyamic acids (this is called "polyamic acid (PA-7)") whose logarithmic viscosity was 1.22 dl/g.

Synthesis example 8 (synthesis of polyamic acid)

In addition to using 4.9 g (0.045 mol) of p-phenylenediamine, 4.8 g (0.015 mol) of 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl and 20.9 g (0.04 mol) of the above Except that the compound represented by formula (7) was used as a diamine compound, 47.7 g of a polyamic acid having a logarithmic viscosity of 1.27 dl/g (this was referred to as "polyamic acid (PA-8)") was obtained in the same manner as in Synthesis Example 6. .

Synthesis example 9 (synthesis of polyamic acid)

In addition to using 13.1g (0.06mol) of 2,3,5,6-benzenetetracarboxylic dianhydride and 7.8g (0.04mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic Acid anhydride, 3.2g (0.03 mole) p-phenylenediamine, 10.0g (0.03 mole) 2,2-bis(4-aminophenyl) hexafluoropropane and 20.9g (0.04 mole) of the compound represented by the above formula (7) Except for the diamine compound, it carried out similarly to the synthesis example 1, and obtained 51.3 g of polyamic acids (this is called "polyamic acid (PA-9)") whose logarithmic viscosity was 1.18dl/g.

Synthesis example 10 (synthesis of polyamic acid)

In addition to using 4.9g (0.045 moles) of p-phenylenediamine, 5.0g (0.015 moles) of 2,2-bis(4-aminophenyl)hexafluoropropane and 20.9g (0.04 moles) of the compound represented by the above formula (7) Except for the diamine compound, it carried out similarly to the synthesis example 9, and obtained 42.3 g of polyamic acids (this is called "polyamic acid (PA-10)") whose logarithmic viscosity was 1.13 dl/g.

Synthesis example 11 (synthesis of polyamic acid)

In addition to using 6.4 g (0.03 mol) of 2,2'-dimethyl-4,4'-diaminobiphenyl, 9.6 g (0.03 mol) of 4,4'-diamino-2,2'-bis(trifluoro Methyl) biphenyl and 20.9g (0.04 moles) the compound represented by above-mentioned formula (7) as diamine compound, operate in the same way as Synthetic Example 9, obtain 46.3g logarithmic viscosity and be the polyamic acid of 1.24dl/g ( It is referred to as "polyamic acid (PA-11)").

Synthesis example 12 (synthesis of polyamic acid)

In addition to using 5.9g (0.03 moles) of 4,4-diaminodiphenylmethane, 13.4g (0.04 moles) of 2,2-bis(4-aminophenyl)hexafluoropropane and 15.7g (0.03 moles) of the above formula ( 7) Except the compound shown as a diamine compound, it carried out similarly to the synthesis example 9, and obtained 50.3 g of polyamic acids (this is called "polyamic acid (PA-12)") whose logarithmic viscosity was 1.33 dl/g.

Synthesis example 13 (synthesis of polyamic acid)

Instead of using 7.9 g (0.04 mol) of 4,4-diaminodiphenylmethane, 9.6 g (0.03 mol) of 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl and 15.7 g (0.03 moles) except that the compound represented by the above-mentioned formula (7) is used as a diamine compound, it is operated in the same manner as Synthetic Example 9 to obtain 43.8 g of polyamic acid (which is referred to as "polyamic acid (PA -13)").

Synthesis example 14 (synthesis of polyamic acid)

In addition to using 9.8g (0.045 moles) of 2,3,5,6-benzenetetracarboxylic dianhydride, 6.7g (0.015 moles) of 4,4-(2,2-hexafluoroisopropylidene) diphthalamide Acid anhydride and 9.0g (0.04 mole) 2,3,5-tricarboxy cyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 6.5g (0.06 mole) p-phenylenediamine and 20.9g (0.04 mole) above-mentioned formula ( 7) Except the compound shown as a diamine compound, it carried out similarly to the synthesis example 1, and obtained 44.8 g of polyamic acids (this is called "polyamic acid (PA-14)") whose logarithmic viscosity was 1.06 dl/g.

Synthesis example 15 (synthesis of polyamic acid)

In addition to using 6.5g (0.03 moles) of 2,3,5,6-benzenetetracarboxylic dianhydride, 13.3g (0.03 moles) of 4,4-(2,2-hexafluoroisopropylidene) diphthalamide Anhydride and 9.0g (0.04 moles) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, the same operation as in Synthesis Example 14, to obtain 24.3g of a logarithmic viscosity of 1.36dl/g Polyamic acid (referred to as "polyamic acid (PA-15)").

Comparative Example 1 (synthesis of polyamic acid)

10.9 g (0.05 mol) of 2,3,5,6-benzenetetracarboxylic dianhydride as tetracarboxylic dianhydride and 11.2 g (0.05 mol) of 2,3,5-tricarboxycyclopentyl acetic dianhydride, P-phenylenediamine 8.7g (0.08 mole) as diamine compound, compound 10.5g (0.02 mole) represented by above-mentioned formula (7) are dissolved in 185g N-methyl-2-pyrrolidone, react 4 at 40 ℃ Hour. Next, the reaction solution was poured into a large excess of methanol to precipitate the reaction product. Then, it was washed with methanol and dried at 40° C. under reduced pressure for 15 hours to obtain 24.7 g of a polyamic acid having a logarithmic viscosity of 1.32 dl/g (this was referred to as “polyamic acid (PA-16)”).

Comparative example 2

13.1 g (0.06 mol) of 2,3,5,6-benzenetetracarboxylic dianhydride and 7.8 g (0.04 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride ), 4.3 g (0.04 mol) of p-phenylenediamine as a diamine compound, 5.9 g (0.03 mol) of 4,4-diaminodiphenylmethane, and 15.7 g (0.03 mol) of the compound represented by the above formula (7) Dissolve in 185g N-methyl-2-pyrrolidone and react at 40°C for 4 hours. Next, the reaction solution was poured into a large excess of methanol to precipitate the reaction product. Then, it was washed with methanol and dried at 40° C. under reduced pressure for 15 hours to obtain 25.2 g of a polyamic acid having a logarithmic viscosity of 1.14 dl/g (this was referred to as “polyamic acid (PA-17)”).

Comparative example 3

19.6 g (0.1 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride, 5.4 g (0.05 mol) of p-phenylenediamine as diamine compound, 4, 4.0 g (0.02 mol) of 4-diaminodiphenylmethane and 15.7 g (0.03 mol) of the compound represented by the above formula (7) were dissolved in 185 g of N-methyl-2-pyrrolidone and reacted at 40° C. for 4 hours. Next, the reaction solution was poured into a large excess of methanol to precipitate the reaction product. Then, it was washed with methanol and dried at 40° C. under reduced pressure for 15 hours to obtain 41.7 g of a polyamic acid having a logarithmic viscosity of 1.03 dl/g (this is referred to as “polyamic acid (PA-18)”).

Example 1

Dissolve the polyamic acid (PA-1) prepared in Synthesis Example 1 in a mixed solvent (weight ratio 50/50) of N-methyl-2-pyrrolidone/butyl cellosolve, and dissolve with respect to 100 parts by weight of polymer 40 parts by weight of polyethylene glycol diglycidyl ether (epoxy compound 1: molecular weight about 400) was prepared as a solution with a solid content of 4% by weight. This solution was filtered with a filter having a pore diameter of 1 μm to prepare the vertical liquid crystal aligning agent of the present invention.

The above-mentioned vertical liquid crystal aligning agent (the film-forming composition) was coated on a transparent conductive film made of an ITO film provided on one side of a glass substrate with a thickness of 1 mm by a spin coater, and dried at 200° C. for 60 minutes to form a dry film. Coating film with a film thickness of 0.08 μm.

Then, on each outer edge of the substrate with the liquid crystal alignment film coated with the above-mentioned liquid crystal alignment film among a pair of transparent electrodes/transparent electrode substrates, an epoxy resin bonded by adding alumina balls with a diameter of 5.5 μm is applied. After the mixture, the faces of the liquid crystal alignment film are overlapped and pressed together, and then the adhesive is cured. Next, after filling the space between the substrates with nematic liquid crystal (MLC-2038, manufactured by Melk Corporation) through the liquid crystal injection port, the liquid crystal injection port was sealed with an acrylic photocurable adhesive, and polarizers were attached to both surfaces outside the substrate. , to produce a liquid crystal display element. The obtained liquid crystal display elements were evaluated for vertical alignment, voltage retention and residual voltage.

Moreover, the liquid crystal aligning agent of this invention prepared above was apply|coated on the ITO board|substrate of thickness 1.5mm using the spin coater similarly, and it formed the coating film similarly to the time of manufacture of a liquid crystal display element. 8 μl of nematic liquid crystal (MLC-2038, manufactured by Merck Co., Ltd.) was dropped on the obtained substrate on which the liquid crystal alignment film was formed using a syringe with a tip diameter of 0.5 mm, and the contact angle between the alignment film and the liquid crystal at 50 seconds after the dropping was measured. The evaluation results are listed in Table 1. Since the liquid crystal aligning agent obtained by this invention has a small contact angle with a liquid crystal, it was confirmed that the wettability of a liquid crystal is favorable, and it has a high voltage retention rate and low residual voltage.

Examples 2-65, Comparative Examples 1-13

According to the formula shown in the following table, dissolve the polyamic acid polymer shown in the table and the compound containing epoxy group (epoxy compound 1~3) in the mixture of N-methyl-2-pyrrolidone/butyl cellosolve In the mixed solvent, a solution having a solid content of 4.0% was obtained, and this solution was filtered with a filter having a pore diameter of 1 μm to prepare the liquid crystal aligning agent of the present invention. Using the liquid crystal aligning agent prepared in this way, it carried out similarly to Example 1, formed the coating film on the board|substrate surface, and produced the liquid crystal display element using the board|substrate with this liquid crystal aligning film formed. Then, the contact angle with liquid crystal, vertical alignment, voltage retention and residual voltage were evaluated. The results are listed in Table 1 together.

Table 1 Example polymer Types of epoxy-containing compounds (parts by weight) liquid crystal wettability voltage retention residual voltage vertical orientation Example 1 PA-1 none good 98.7 good good Example 2 PA-1 Epoxy Compound 1(20) good 99.2 good good Example 3 PA-1 Epoxy compound 1(40) good 99.1 good good Example 4 PA-2 Epoxy compound 2(20) good 99.1 good good Example 5 PA-2 Epoxy compound 2(40) good 99.0 good good Example 6 PA-2 none good 98.9 good good Example 7 PA-2 Epoxy Compound 1(20) good 99.3 good good Example 8 PA-2 Epoxy Compound 2(10) good 99.1 good good Example 9 PA-2 Epoxy compound 2(20) good 99.2 good good Example 10 PA-2 Epoxy compound 2(40) good 99.2 good good Example 11 PA-2 Epoxy compound 3(20) good 99.3 good good Example 12 PA-3 none good 99.0 good good Example 13 PA-3 Epoxy Compound 1(20) good 99.0 good good Example 14 PA-3 Epoxy compound 2(20) good 99.0 good good Example 15 PA-3 Epoxy compound 2(40) good 99.1 good good Example 16 PA-3 Epoxy compound 3(20) good 99.0 good good Example 17 PA-4 none good 99.0 good good Example 18 PA-4 Epoxy Compound 1(20) good 99.0 good good Example 19 PA-4 Epoxy compound 2(20) good 99.1 good good Example 20 PA-4 Epoxy compound 2(40) good 99.0 good good Example 21 PA-4 Epoxy compound 3(20) good 99.0 good good Example 22 PA-5 Epoxy Compound 1(20) good 99.2 good good Example 23 PA-5 Epoxy compound 2(20) good 99.0 good good Example 24 PA-5 Epoxy compound 3(20) good 99.0 good good Example 25 PA-6 Epoxy Compound 1(10) good 99.1 good good Example 26 PA-6 Epoxy Compound 2(10) good 99.1 good good Example 27 PA-6 Epoxy compound 2(20) good 99.3 good good Example 28 PA-6 Epoxy compound 2(40) good 99.2 good good Example 29 PA-6 Epoxy compound 3(20) good 99.1 good good Example 30 PA-7 none good 98.8 good good Example 31 PA-7 Epoxy compound 1(40) good 99.3 good good Example 32 PA-7 Epoxy compound 2(40) good 99.2 good good Example 33 PA-7 Epoxy compound 3(20) good 99.3 good good Example 34 PA-8 Epoxy Compound 1(10) good 99.0 good good Example 35 PA-8 Epoxy Compound 1(20) good 99.1 good good Example 36 PA-8 Epoxy compound 2(20) good 99.1 good good Example 37 PA-8 Epoxy compound 3(20) good 99.0 good good Example 38 PA-9 none good 99.4 good good Example 39 PA-9 Epoxy Compound 1(20) good 99.4 good good Example 40 PA-9 Epoxy compound 2(20) good 99.2 good good Example 41 PA-9 Epoxy compound 2(40) good 99.4 good good Example 42 PA-10 Epoxy Compound 1(20) good 99.2 good good Example 43 PA-10 Epoxy compound 2(20) good 99.0 good good Example 44 PA-10 Epoxy compound 3(20) good 99.2 good good Example 50 PA-12 Epoxy Compound 1(20) good 98.9 good good Example 51 PA-12 Epoxy compound 2(20) good 98.8 good good Example 52 PA-12 Epoxy compound 2(40) good 98.9 good good Example 58 PA-14 Epoxy Compound 1(20) good 99.5 good good Example 59 PA-14 Epoxy compound 2(20) good 98.9 good good Example 60 PA-14 Epoxy compound 3(20) good 98.8 good good Example 61 PA-15 none good 99.0 good good Example 62 PA-15 Epoxy Compound 1(10) good 98.7 good good Example 63 PA-15 Epoxy Compound 1(20) good 99.4 good good Example 64 PA-15 Epoxy compound 2(20) good 99.2 good good Example 65 PA-15 Epoxy compound 2(40) good 99.1 good good

Table 1 (continued) Comparative example 1 PA-16 none bad 99.0 good good Comparative example 2 PA-16 Epoxy Compound 1(20) bad 99.4 good good Comparative example 3 PA-16 Epoxy compound 2(20) bad 99.3 good good Comparative example 4 PA-16 Epoxy compound 2(40) bad 99.4 good good Comparative Example 5 PA-16 Epoxy compound 3(20) bad 99.2 good good Comparative example 6 PA-17 none bad 98.6 good good Comparative Example 7 PA-17 Epoxy Compound 1(20) bad 98.9 good good Comparative Example 8 PA-17 Epoxy compound 1(40) bad 99.2 good good Comparative Example 9 PA-17 Epoxy compound 2(20) bad 99.2 good good Comparative Example 10 PA-17 Epoxy compound 2(40) bad 99.0 good good Comparative Example 11 PA-18 Epoxy Compound 1(20) bad 99.1 good good Comparative Example 12 PA-18 Epoxy compound 2(20) bad 99.1 good good Comparative Example 13 PA-18 Epoxy compound 3(20) bad 99.1 good good

Epoxy Compound 1: Polyethylene Glycol Diglycidyl Ether

Epoxy compound 2: N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane

Epoxy compound 3: 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane

Claims (6)

1. vertical alignment-type liquid crystal aligning agent is characterized in that comprising the polymkeric substance that the acid imide repetitive by the amic acid repetitive of (i) following formula (I-1) expression and/or (ii) following formula (I-2) expression constitutes,

Wherein, P ¹And Q ¹Be respectively the organic group of 4 valencys and divalent, and P wherein ¹And Q ¹At least one of them is the group that contains fluorine atom;

Wherein, P ²And Q ²Be respectively the organic group of 4 valencys and divalent, and P wherein ²And Q ²At least one of them is the group that contains fluorine atom.

2. the described aligning agent for liquid crystal of claim 1, the P in the wherein above-mentioned formula (I-1) ¹With the P in the above-mentioned formula (I-2) ²The 4 valency organic groups that contain the contain fluorine atoms of the following formula of 1-50 mole % (II-1) expression independently of one another,

A wherein ¹And A ²At least one of them, perhaps A ³And A ⁴At least one of them is fluorine atom or fluoro-alkyl, and remaining is hydrogen atom or alkyl.

3. the described aligning agent for liquid crystal of claim 1, the Q in the wherein above-mentioned formula (I-1) ¹With the Q in the above-mentioned formula (I-2) ²The divalent organic group that contains the contain fluorine atoms of the following formula of 1-60 mole % (III-1) expression independently of one another,

Wherein, A ⁵And A ⁶At least one of them is fluorine atom or fluoro-alkyl, and remaining is hydrogen atom or alkyl, and A ⁷And A ⁸Be the hexafluoro propylidene.

4. the described aligning agent for liquid crystal of claim 1, the P in the wherein above-mentioned formula (I-1) ¹With the P in the above-mentioned formula (I-2) ²Contain at least a group in the 4 valency organic groups of at least 10 moles of following formulas of % (IV-1) expressions independently of one another,

Wherein, R ¹, R ², R ³, R ⁴And R ⁵Be 1 valency organic group of hydrogen atom or non-contain fluorine atoms independently of each other.

5. the described aligning agent for liquid crystal of claim 1, the Q in the wherein above-mentioned formula (I-1) ¹With the Q in the above-mentioned formula (I-2) ²Represent following formula (V-1) and (V-2) independently of one another,

Wherein, R ⁶Be to have the divalent organic group that carbon number is 4～40 ester ring type skeleton, R ⁷Be carbon number be 10-20 alkyl, have the 1 valency organic group that carbon number is the ester ring type skeleton of 4-40, X be singly-bound ,-O-,-CO-,-COO-,-OCO-,-NHCO-,-CONH-,-S-, methylene, carbon number are alkylidene and the phenylene of 2-6.

6. a vertical liquid crystal display element is characterized in that having the vertical liquid crystal tropism film that is made by any described vertical alignment-type liquid crystal aligning agent of claim 1～5.