KR20060048216A - Liquid crystal alignment agent and liquid crystal display - Google Patents

Abstract

Provided is a vertical alignment liquid crystal display element which is excellent in the vertical alignment property and the voltage retention, and does not produce contrast spots and display defects even when left under high humidity, and a liquid crystal aligning agent for the same.

A vertical alignment liquid crystal aligning agent containing 100 parts by weight of an aromatic polyamide obtained by reacting a tetracarboxylic dianhydride and a diamine compound and / or an imidized polymer thereof and 0.01 to 100 parts by weight of a compound containing two or more epoxy groups in a molecule thereof. .

Description

Liquid crystal aligning agent and liquid crystal display device {LIQUID CRYSTAL ALIGNMENT AGENT AND LIQUID CRYSTAL DISPLAY}

The present invention relates to a liquid crystal aligning agent and a liquid crystal display device. In addition, the present invention relates to a liquid crystal alignment agent capable of giving a liquid crystal alignment film excellent in vertical alignment, voltage retention and moisture resistance, and a highly reliable liquid crystal display device comprising the liquid crystal alignment film.

At present, as a liquid crystal display element, a liquid crystal aligning film which consists of aromatic polyamide, polyimide, etc. is formed in the surface of the board | substrate with which the transparent conductive film is provided, and it is set as a board | substrate for liquid crystal display elements, and the two sheets are opposingly arranged, and positive in the clearance gap is carried out. A so-called TN (Twisted Nematic) liquid crystal cell in which a nematic liquid crystal layer having dielectric anisotropy is formed to form a sandwich cell, and the long axis of the liquid crystal molecules is continuously twisted by 90 ° from one substrate to the other substrate. TN type liquid crystal display elements having a known structure are known. In addition, STN (Super Twisted Nematic) type liquid crystal display devices having a higher contrast and less visual dependence than TN type liquid crystal display devices and vertically aligned liquid crystal display devices have been developed. This STN type liquid crystal display element is produced by blending a nematic liquid crystal with a chiral agent, which is an optically active substance, as a liquid crystal, and is caused by the long axis of the liquid crystal molecules being continuously twisted over 180 ° between the substrates. It is to use the birefringence effect.

On the other hand, a vertical alignment type liquid crystal display device called a multi domain vertical alignment (MVA) method or a patterned vertical alignment (PVA) has been proposed. These MVA type and PVA type liquid crystal display elements are excellent in viewing angle, contrast, etc., and also excellent in terms of the manufacturing process, such as not having to perform a rubbing treatment in the form of the liquid crystal alignment film. As a liquid crystal aligning film suitable for MVA system and PVA system, what is excellent in vertical alignment property is calculated | required.

In addition, in recent years, liquid crystal display devices have also made remarkable developments as high-performance display devices in terms of size, light weight, low power consumption, and the like, and demanded performances for liquid crystal alignment films have become increasingly stringent. In particular, in the low voltage drive type liquid crystal display device for the purpose of lowering power consumption, there is a strict demand for a voltage holding ratio and a reliability test for applying a voltage for a long time at a high temperature. In addition, the alignment film absorbs moisture in the air in the manufacturing process. There exists also the problem of the orientation unevenness generate | occur | produced by this, and the solution of this problem is urgently urged. However, in the liquid crystal aligning film suitable for the conventional MVA system and the PVA system, although the epoxy group has an alignment agent structure like patent document 1 and patent document 2, it is also seen that it is excellent in a vertical alignment property and an electrical property, for example, It is not yet solved the problem of moisture absorption. Under these circumstances, it is expected to develop a liquid crystal alignment agent that provides a liquid crystal alignment film having excellent moisture resistance without compromising electrical characteristics such as voltage retention.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2002-323701

[Patent Document 2] Japanese Patent Application Laid-Open No. 2004-94179

It is an object of the present invention to provide a liquid crystal aligning agent which gives a liquid crystal aligning film excellent in vertical alignment, voltage retention and moisture resistance.

Another object of the present invention is to provide a liquid crystal display device comprising the liquid crystal alignment film.

Still other objects and advantages of the present invention will become apparent from the following description.

According to the present invention, the above object and advantages of the present invention, first,

(A) 100 weight of the aromatic polyamide (henceforth "specific polymer I") and / or its imidation polymer (henceforth "specific polymer II") obtained by making tetracarboxylic dianhydride and a diamine compound react. Wealth, and

(B) 0.01-100 weight part of compounds containing two or more epoxy groups in a molecule | numerator, It is achieved by the vertical alignment liquid crystal aligning agent.

According to the present invention, the above object and advantages of the present invention are secondly achieved by a vertically aligned liquid crystal display device comprising a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

Aromatic Polyamides and Imide Polymerized Polymers

In this invention, the aromatic polyamide obtained by making tetracarboxylic dianhydride and a diamine compound react, and / or its imidation polymer is used.

As tetracarboxylic dianhydride used in this invention, aliphatic tetra carboxylic dianhydride, alicyclic tetra carboxylic dianhydride, and aromatic tetra carboxylic dianhydride are mentioned, for example.

As aliphatic tetracarboxylic dianhydride, butane tetracarboxylic dianhydride is mentioned, for example.

As the alicyclic tetracarboxylic dianhydride, for example, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride Water, 1,3-dimethyl-1,2,3,4-cyclobutane tetra carboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclobutane tetra carboxylic dianhydride, 1, 2,3,4-tetramethyl-1,2,3,4-cyclobutane tetra carboxylic dianhydride, 1,2,3,4-cyclopentane tetra carboxylic dianhydride, 1,2,4,5 -Cyclohexane tetracarboxylic dianhydride, 3,3 ', 4,4'-dicyclohexyl tetra carboxylic dianhydride, cis3,7-dibutylcycloocta-1,5-diene-1,2, 5,6-tetra carboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic dianhydride, 3,5,6-tricarbonyl-2-carboxynorbornane-2: 3,5: 6- Dianhydride, 2,3,4,5-tetrahydrofuran tetra carboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5 (tet Lahydro-2,5-dioxo-3-pranyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5 -Methyl-5 (tetrahydro-2,5-dioxo3-pranyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b- Hexahydro-5-ethyl-5 (tetrahydro-2,5-dioxo-3-pranyl) -naphtho [1,2-c] -furan-1,3-dione, 1,3,3a, 4 , 5,9b-hexahydro-7-methyl-5- (tetrahydro-2,5-dioxo-3-pranyl) -naphtho [1,2-c] -furan-1,3-dione, 1 , 3,3a, 4,5,9b-hexahydro-7-ethyl-5 (tetrahydro-2,5-dioxo3-pranyl) -naphtho [1,2-c] -furan-1,3 -Dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5 (tetrahydro-2,5-dioxo-3-pranyl) -naphtho [1,2-c]- Furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-ethyl--5 (tetrahydro-2,5-dioxo-3-pranyl) -naphtho [1 , 2-c] -furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8-dimethyl-5 (tetrahydro-2,5-dioxo-3-pra Nil) -naphtho [1,2-c] -furan-1,3-dione, 5- (2,5-dioxotetrahydrofuran) -3-methyl-3-si Chlohexene-1,2-dicarboxylic dianhydride, bicyclo [2.2.2] -octo-7-ene-2,3,5,6-tetracarboxylic dianhydride, formulas (a) and ( The compound represented by b) etc. are mentioned.

[Formula 1]

(In formula, R <^1> and R <^4> represents the divalent organic group which has an aromatic ring, R <^2> and R <^3> represents a hydrogen atom or an alkyl group, and ^two or more R <^2> and R <^3> may be same, respectively. good.)

Moreover, as aromatic tetracarboxylic dianhydride, it is 3,3 ', 4,4'- benzophenone tetracarboxylic dianhydride, 3,3', 4,4'-biphenyl sulfontetra carboxylic acid, for example. Dianhydrides, 1,4,5,8-naphthalene tetra carboxylic dianhydride, 2,3,6,7-naphthalene tetra carboxylic dianhydride, 3,3 ', 4,4'-biphenylethertetra Carboxylic acid dianhydride, 3,3 ', 4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3', 4,4'-tetraphenylsilanetetracarboxylic dianhydride, 1,2 , 3,4-furan tetracarboxylic 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'-perfluoro isopropylidenediphthalic dianhydride , 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride, bis (phthalic acid) phenylphosphineoxa Dianhydrides, p-phenylene-bis (triphenylphthalic acid) dianhydrides, m-phenylene-bis (triphenylphthalic acid) dianhydrides, bis (triphenylphthalic acid) -4,4'-diphenylether dianhydrides, bis (Triphenylphthalic acid) -4,4'- diphenylmethane dianhydride, ethylene glycol -bis (anhydrotrimerate), propylene glycol -bis (anhydrotrimerate), 1, 4- butanediol-bis (an Hydrotrimerate), 1,6-hexanediol-bis (anhydrotrimerate), 1,8-octanediol-bis (anhydrotrimerate), 2,2-bis (4-hydroxyphenyl) Propane-bis (anhydrotrimerate), the compound represented by following formula (1)-(4), etc. are mentioned. These are used individually by 1 type or in combination of 2 or more types.

[Formula 2]

Among these tetracarboxylic dianhydrides, aromatic polyamides having at least 50 mol% of cycloaliphatic tetracarboxylic dianhydrides and imidized polymers thereof are preferable in terms of voltage retention. Preferred alicyclic tetracarboxylic dianhydrides include 1,2,3,4-cyclobutane tetra carboxylic dianhydride and 1,3-dimethyl-1,2,3,4-cyclobutane tetra carboxylic dianhydride. , 1,2,3,4-cyclopentane tetracarboxylic dianhydride, 2,3,5-tricarboxy cyclopentyl acetate dianhydride, 5- (2,5-dioxo tetra hydrofural) -3-methyl- 3-cyclohexene-1,2-dicarboxylic dianhydride, cis-3,7-dibutylcycloocta-1,5-diene-1,2,5,6-tetra carboxylic acid dianhydride, 3, 5,6-tricarbonyl-2-carboxynorbornane-2: 3, 5: 6-dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5 -Dioxo-3-pranyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetra Hydro-2,5-dioxo-3-pranyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5,8 -Dimethyl-5- (tetrahydro-2,5-dioxo-3-pranyl) -naphtho [1,2-c] furan-1,3-dione, bicyclo [ 2.2.2] -octo-7-ene-2,3,5,6-tetracarboxylic dianhydride, the compound represented by the following formulas (5) to (7) among the compounds represented by the formula (a); and The compound represented by following formula (8) is mentioned among the compound represented by said formula (b). As particularly preferred, 1,2,3,4-cyclobutane tetra carboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutane tetra carboxylic dianhydride, 2,3,5- Tricarboxy cyclopentyl acetate dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo3-pranyl) -naphtho [1,2-c] Furan-1,3-dione, cis-3,7-dibutylcycloocta-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, 3,5,6-tricarbonyl- 2-carboxynorbornane-2: 3, 5: 6-dianhydride, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo3 -Pranil) -naphtho [1,2-c] furan-1,3-dione and the compound represented by following formula (5) are mentioned.

[Formula 3]

As the diamine compound used in the present invention, for example, p-phenylenediamine, m-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4 '-Diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminobenzanilide, 4,4 '-Diaminodiphenylether, 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'-diaminodiphenylether, 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-aminophen Benzene, 1,3-bis (3-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) -10-hydroanthracene, 2,7-diamino fluorene, 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-phenyl Lenisopuropyridene) bisaniline, 4,4 '-(m-phenyleneisopropyridene) bisaniline, 2,2'-bis [4- (4-amino-2-trifluoromethylphenoxy) Phenyl] hexafluoropropane, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-bis [(4-amino2-trifluoromethyl) phenoxy Aromatic diamines such as] -octafluorobiphenyl;

1,1-methaxylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, 4,4-diaminoheptamethylenediamine , 1,4-diaminocyclohexane, isophoronediamine, tetrahydrobicyclopentadienylenediamine, hexahydro-4,7-methanoindenylenedimethylenediamine, tricyclo [6.2.1.02,7] -undecylenedimethyl Aliphatic and alicyclic diamines such as diamine and 4,4'-methylenebis (cyclohexyl amine);

2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 5,6-diamino-2,3-dicyanopyridine, 5 , 6-diamino-2,4-dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-triazine, 1,4-bis (3-aminopropyl) pipera Dean, 2,4-diamino-6-isopropoxy-1,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4-dia Mino-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-dimethyluracil, 3, 5-diamino-1,2,4-triazole, 6,9-diamino-2-ethoxyacridine lactate, 3,8-diamino-6-phenylphenanthridine, 1,4-diaminopipe 2 in a molecule | numerator, such as a raazine, 3, 6- diamino acridine, bis (4-aminophenyl) phenyl amine, and the compound represented by following formula (i)-(ii) A primary amino group and a diamine having a nitrogen atom other than the primary amino group;

[Formula 4]

(Wherein R ⁵ represents a monovalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, and X represents a divalent organic group.)

[Formula 5]

Wherein R ⁶ represents a divalent organic group having a ring structure containing a nitrogen atom selected from pyridine, pyrimidine, triazine, piperidine and piperazine, X represents a divalent organic group, and a plurality of X may be the same or different.)

Monosubstituted phenylene diamines represented by the following formula (III); Diamino organosiloxane represented by the following formula (IV);

[Formula 6]

(In formula, R <^7> represents the bivalent organic group chosen from -O-, -COO-, -OCO-, -NHCO-, -CONH-, and -CO-, R <^8> is a steroid skeleton, a trifluoro Monovalent organic group or a C6-C30 alkyl group which has group chosen from a methyl group and a pulluro group.)

[Formula 7]

(In formula, R <^9> represents a C1-C12 hydrocarbon group, two or more R <^9> may be the same respectively, and p is an integer of 1-3, q is an integer of 1-20.)

The compound etc. which are represented by following formula (9)-(13) are mentioned. These diamine compounds can be used individually or in combination of 2 or more types.

[Formula 8]

/CH3

/ CH3

 (In formula, y is an integer of 2-12, z is an integer of 1-5.)

Among them, p-phenylene diamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,7-diaminofluorene, 4 , 4'-diaminodiphenylether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4 -(4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4 , 4 '-(m-phenylenediisopropylidene) bisaniline, 1,4-cyclohexanediamine, 4,4'-methylenebis (cyclohexyl amine), 1,4-bis (4-aminophenoxy) Benzene, 4,4'-bis (4-aminophenoxy) biphenyl, the compound represented by the formulas (9) to (13), 2,6-diaminopyridine, 3,4-diaminopyridine, 2, 4-diaminopyrimidine, 3,6-diamino acridine, a compound represented by the following formula (14) among the compounds represented by the formula (I), in the formula (II) Among the compounds represented, compounds represented by the following formulas (16) to (21) are preferable among the compounds represented by the following formula (15) and the compounds represented by the formula (III).

[Formula 9]

It is preferable that the usage-amount of the diamine which has a pretilt angle expression component is 2.5-50 mol% in all the diamine.

Specific polymer I used for this invention can be obtained by reaction of tetracarboxylic dianhydride and a diamine compound. Such reaction is carried out in an organic solvent, preferably at a temperature of 0 to 150 캜, more preferably 0 to 100 캜.

The reaction solution is not particularly limited as long as it can dissolve the synthesized polyamic acid, for example. N-methyl-2-pyrrolidone, N, N-dimethylacetamide N, N-dimethylform Aprotic polar solvents such as amide, dimethyl sulfoxide, γ-butylolactone, tetramethyl urea and hexamethylphospholtriamide; and phenol solvents such as m-cresol, xylenol, phenol, and halogenated phenol. In addition, the usage-amount of (alpha) of an organic solvent is a quantity normally that the total amount ((beta)) of tetracarboxylic dianhydride and a diamine compound will be 0.1-30 weight% with respect to the total amount ((alpha) + (beta)) of a reaction solution. desirable.

The use ratio of the tetracarboxylic dianhydride and the diamine compound is preferably such that the acid anhydride group of the tetra carboxylic dianhydride is 0.2 to 2 equivalents to 0.3 equivalents to 1 equivalent of the amino group in the diamine compound. It is more preferable.

The specific polymer II used for this invention is obtained by heating said specific polymer I or imidating in presence of a dehydrating agent and an imidation catalyst. The reaction temperature at the time of imidation by heating becomes like this. Preferably it is 60 degreeC-200 degreeC, More preferably, it is 100 degreeC-170 degreeC. When reaction temperature is less than 60 degreeC, reaction progresses late and when it exceeds 200 degreeC, the molecular weight of soluble polyimide may fall large. Moreover, when imidating in presence of a dehydrating agent and an imidation catalyst, it can carry out in said organic solvent. Reaction temperature becomes like this. Preferably it is 0-200 degreeC, More preferably, it is 60 degreeC-150 degreeC. As the dehydrating agent, for example, acid anhydrides such as acetic anhydride, propionic anhydride and trifluoroacetic anhydride can be used. As the imidization catalyst, tertiary amines such as pyridine, coridine, lutidine, and triethylamine can be used, for example. As the imidization catalyst, tertiary amines such as pyridine, lutidine and triethylamine) can be used, but the present invention is not limited thereto. It is preferable that the usage-amount of a dehydrating agent shall be 1.6-20 mol with respect to 1 mol of repeating units of specific polymer I. In addition, it is preferable that the usage-amount of an imidation catalyst shall be 0.5-10 mol with respect to 1 mol of dehydrating agents to be used.

Each of the specific polymer I and the specific polymer II obtained in this way also has the logarithm point ((eta) 1n), Preferably it is 0.05-10 dl / g, More preferably, it is 0.05-5d l / g.

The value of the logarithmic viscosity ((eta) 1n) in this invention uses N-methyl- 2-pyrrolidone as a solvent, measures the viscosity at 30 degreeC with respect to the solution whose density | concentration is 0.5 g / 100 milliliter, It is calculated | required by Formula (I).

Moreover, it can be used together with the said organic solvent to the extent that a polymer which produces | generates a poor solvent alcohol, a ketone, ester, an ether, a halogenated hydrocarbon, and a hydrocarbon does not precipitate. As such a poor solvent, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, 4-hydroxy-4-methyl-2-pentanone (diacetone alcohol), ethylene glycol, propylene glycol, 1 Alcohols such as, 4-butanediol, triethylene glycol and ethylene glycol monomethyl ether; Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; Esters such as ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate, diethyl oxalate, and diethyl malonate; Diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether acetate, di Ethers such as ethylene 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, tetrahydrofuran; Halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene and hydrocarbons such as hexane, heptane, octane, benzene, toluene, xylene and the like. Can be.

The imidation ratio of the specific polymer II obtained is the absorption (CNC variable vibration = absorption of imide bond) of 1,381 cm <^-1> vicinity in the FT-IR measurement, and the absorption (absorption of amic acid bond) of 1,503 cm <^-1> . From the peak area ratio of), the imidation ratio was computed by the following formula.

Imidation ratio = (α1 / (α1 + α2) 1 × 10O (%)

Peak area of absorption near α ₁ : 381Cm ^-1

the peak area of absorption near α ₂ : 1503cm ^-1

In addition, (alpha) ₂ is the value which calculated | required the peak area by O as absorption of 1,503cm <^-1> vicinity, although the coating film was heated for 10 minutes by the 30 degreeC hotplate.

The epoxy compound used in the present invention contains two or more epoxy groups in a molecule. As such an epoxy compound, the compound which has partial structure (i), (ii) or (iii) is preferable.

[Formula 10]

(Wherein R represents hydrogen or a monovalent organic group having 1 to 20 carbon atoms, k represents 1 to 3, 1 represents 1 to 3, m represents 1 to 4, and n represents an integer of 1 to 20.)

As a compound which has partial structure, a noblock phenol type epoxy compound is mentioned, for example. Japan Epoxy Resin Co., Ltd. product brand names EPIKOTE-152, copper-154, EPICURE-MP402FPY, copper-YLH129B65, etc. can be illustrated. As a compound which has partial structure (ii), 1, 12, 2- tetrakis (hydroxyphenyl) ethane type solid epoxy resin, EPIKOTE-1031S, etc. are mentioned, for example. Examples of the compound having a partial structure include 3,4-epoxycyclohexenylmethyl-3 ', 4'-epoxycyclohexyl carboxylate, Daicel Chemical Industry Co., Ltd. product name Ceroxide 2021 -A, Copper-P and the like. These epoxy compounds can be used 1 type or in combination of 2 or more types.

In addition, although most of the epoxy compounds here are high molecular weight bodies, the epoxy compound used for this invention is not restrict | limited by molecular weight.

The liquid crystal aligning agent of this invention can be advantageously prepared by adding an epoxy compound to the solution containing specific polymer I and / or specific polymer II, for example. As a solvent used at this time, the same solvent as the above-mentioned solvent is mentioned.

The use ratio of an epoxy compound is 0.01 to 100 weight part with respect to 100 weight part of specific polymer I and / or specific polymer II.

Although the liquid crystal aligning agent of this invention contains specific polymer I and / or specific polymer II, although monoamine is added at the time of reaction, in order to adjust the molecular weight of these specific polymers, and to realize the optimum coating property to a board | substrate, good.

As the monoamine used at this time, for example, aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n- Decyl amine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine and n-eicosylamine.

The liquid crystal aligning agent of this invention is used for the vertical alignment liquid crystal display element in which at least one board | substrate which forms a liquid crystal cell has protrusion shape or pattern shape. The shape is used as the orientation control means of the device. As such a liquid crystal display element, the liquid crystal display element of MVA system is mentioned, for example. MVA mode means “liquid crystal Vol. 3 No. 2117 (1999) "and Japanese Unexamined Patent Application Publication No. 11-258605, the vertical alignment mode in which the projections are used for the orientation regulating means is shown. The projections and patterns are respectively on the TFT substrate side and the color filter side. It may be provided in the present invention, for example, may have projections on the color filter side, and may have both orientation control means, such as having a pattern on TFT side.

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

(1) The liquid crystal aligning agent of this invention is apply | coated to the one surface of the liquid crystal clamping | substrate board | substrate with which the patterned transparent conductive film was provided by methods, such as a roll coater method, a spinner method, and a printing method, and then a coating surface is heated. This forms a coating film. The heating temperature after liquid crystal aligning agent application | coating is preferably 80-300 degreeC, More preferably, it is 120-250 degreeC. Although the liquid crystal aligning agent of this invention forms the coating film used as an oriented film by removing an organic solvent after application | coating, it can also be made into the imidized coating film by advancing dehydration ring by heating.

The film thickness of the formed coating film becomes like this. Preferably it is 0.01-1 micrometer, More preferably, it is 0.05-0.5 micrometer.

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

The liquid crystal aligning agent of this invention may contain the functional silane containing compound from a viewpoint of improving adhesiveness with respect to the surface of a board | substrate within the range which does not impair the objective physical property. As such a functional silane containing compound, 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 2-aminopropyl trimethoxysilane, 2-aminopropyl triethoxysilane, N- (2-aminoethyl) -3-aminopropofyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureapropyltrimethoxysilane, 3-ureapropyl Triethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N -Trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxy Cyryl-3,6-diazanyl acetate, 9-triethoxysilyl-3,6-diazanyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N- Jyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltri Methoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, etc. are mentioned.

Two board | substrates with a liquid crystal aligning film were produced as mentioned above, two board | substrates are opposingly arranged through a gap (cell gap), and the periphery of two board | substrates is pasted using a sealing agent, and partitioned by the board surface and a sealing agent. A negative type nematic liquid crystal is injected and filled into the formed cell gap, and the injection hole is sealed to form a liquid crystal cell. And a liquid crystal display element is obtained by making a polarizing plate mutually adhere | attach on the outer surface of a liquid crystal cell, ie, the other surface side of each board | substrate which comprises a liquid crystal cell.

As the sealant, for example, an epoxy resin or the like containing an aluminum oxide sphere as a curing agent and a spacer can be used.

As a liquid crystal, a nematic liquid crystal and a smectic liquid crystal are mentioned, for example. Especially, a nematic liquid crystal is preferable, For example, a siphonbase type liquid crystal, a subfamily clock liquid crystal, a biphenyl type liquid crystal, a phenyl cyclohexane type liquid crystal, an ester type liquid crystal, a terphenyl type liquid crystal, a biphenyl cyclohexane type liquid crystal, a flute A midine liquid crystal, a dioxane liquid crystal, a bicyclooctane type liquid crystal, a cuban type liquid crystal, etc. can be used. In addition, these liquid crystals are, for example, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonaate, cholesteryl carbonate, and trade names "C-15" and "CB-15" (manufactured by Merck Co., Ltd.). And a chiral agent such as that commercially available may be added and used. Ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino2-methylbutylcinnamate can also be used.

Moreover, as a polarizing plate adhere | attached on the outer surface of a liquid crystal cell, the polarizing plate which consisted of the polarizing film called H film which absorbed the iodine, and absorbed iodine with the cellulose acetate protective film, or the polarizing plate which consists of them is mentioned.

EXAMPLE

Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not restrict | limited to these Examples. In addition, the evaluation item and evaluation method of the liquid crystal aligning agent prepared in the following example and the comparative example are shown below.

(Vertical orientation of liquid crystal molecules)

Vertical alignment of the vertical alignment liquid crystal display device observed the liquid crystal display device at voltage OFF and 12 V (peak-peak), and judged it as "good" when there was no abnormal domain.

(Moisture Resistance Test of Liquid Crystal Display Device)

The moisture resistance of the vertically oriented liquid crystal display device was good when the device was left at room temperature and under high humidity (90% RH), and the abnormal domain in the liquid crystal cell was not confirmed when the voltage was turned on and off.

(Reliability Test of Liquid Crystal Display Device)

The reliability of the liquid crystal aligning agent was applied to a vertical alignment liquid crystal display device by applying a rectangular wave of 30 Hz and 3.0 V in which a direct current 6.0 V and an AC 6.0 V (peak-peak) was applied at 167 hours at an environment temperature of 70 ° C. Was turned off, and after the residual image was erased, it was visually confirmed whether or not the image was vertically aligned uniformly.

(Voltage retention)

When applied to a liquid crystal display at a temperature of 40 ° with a voltage of 3 V, an application time of 60 microseconds, and a span of 167 milliseconds, a holding voltage of 167 milliseconds after the release of 3 V is applied to VHR-1 manufactured by Toyo Technica Co., Ltd. It measured and calculated the voltage retention. At this time, negative MLC-2038 (manufactured by Merck) was used as the liquid crystal.

Synthesis Example 1

2.3 g of 2,3,5-tricarboxycyclopentyl acetate dianhydride, 0.88 g of p-phenylene diamine, and 1.1 g of the diamine compound represented by the above formula (9) were added to 16.8 g of N-methyl-2-pyrrolidone. It melt | dissolved and made it react at 60 degreeC for 5 hours. Next, the reaction mixture was poured into a large excess of methanol and the reaction product precipitated out. Thereafter, the mixture was washed with methanol and dried at 40 ° C. under reduced pressure for 15 hours to obtain 55.6 g of specific polymer Ia.

The specific polymer Ia obtained in Synthesis Example 1 was dissolved in 39.0 g of N-methyl-2-pyrrolidone, 0.88 g of pyridine and 1.13 g of acetic anhydride were added and imidized at 110 ° C. for 4 hours. Next, the reaction product was precipitated in the same manner as in Synthesis example 1 to obtain 53.0 g of specific polymer IIa having an intrinsic viscosity of 0.63 dL / g. Table 1 shows the imidation ratio of the obtained specific polymer IIa.

Synthesis Example 2

1.89 g of 2,3,5-tricarboxycyclopentyl acetate dianhydride, 0.55 g of p-phenylene diamine, and 1.76 g of the diamine compound represented by the above formula (9) were added to 16.8 g of N-methyl-2-pyrrolidone. Except for dissolving, it carried out similarly to the synthesis example 1, and obtained 55.7g of specific polymer Ib.

The specific polymer Ib obtained by the synthesis example 1 was dissolved in 39.0 g of N-methyl-2-pyrrolidone, 0.73 g of pyridine and 0.95 g of acetic anhydride were added, and imidization was performed at 110 degreeC for 4 hours. Next, the reaction product was precipitated in the same manner as in Synthesis example 1 to obtain 52.1 g of specific polymer IIb having an intrinsic viscosity of 0.5 dL / g.

Synthesis Example 3

2.9 g of 2,3,5-tricarboxycyclopentyl acetate dianhydride, 1.1 g of p-phenylene diamine, and 0.6 g of the diamine compound represented by the above formula (9) were added to 16.8 g of N-methyl-2-pyrrolidone. Except for dissolving, it carried out similarly to the synthesis example 1, and obtained 54.1 g of specific polymers Ic.

Specific intrinsic viscosity of 0.32 dL / g was obtained by imidization as in Synthesis Example 1, except that specific polymer Ic, pyridine 1.32 g and acetic anhydride 1.70 g were dissolved in 39.0 g of N-methyl-2-pyrrolidone. 52.5 g of polymer IIc was obtained.

Synthesis Example 4

2.9 g of 2,3,5-tricarboxycyclopentyl acetate dianhydride, 1.1 g of p-phenylene diamine, and 0.6 g of the diamine compound represented by the above formula (9) were added to 16.8 g of N-methyl-2-pyrrolidone. A specific polymer Id 54.6 g was obtained in the same manner as in Synthesis example 1 except for dissolving.

Intrinsic viscosity O.48 dL / g by imidization similarly to Synthesis Example 1, except that specific polymer Id was dissolved in 1.76 g of pyridine and 2.27 g of acetic anhydride in 39.0 g of N-methyl-2-pyrrolidone. 52.1 g of specific polymer IId were obtained.

Synthesis Example 5

4.6 g of 2,3,5-tricarboxyl cyclopentyl acetate dianhydride, 1.5 g of pyromellitic dianhydride, 2.2 g of p-phenylene diamine, and 3.6 g of the diamine compound represented by the above formula (9) were selected from N-methyl- Except having dissolved in 48.0 g of 2-pyrrolidone, 54.0 g of specific polymer Ie having an inherent viscosity of 0.45 dL / g was obtained in the same manner as in Synthesis example 1.

Synthesis Examples 1 to 5

Synthesis Example polymer Intrinsic viscosity dL / g Imidization rate One IIa 0.63 52% 2 IIb 0.50 50% 3 IIc 0.32 60% 4 IId 0.48 80% 5 Ie 0.45 0%

Examples 1-9 and Comparative Examples 1-5

Example 1

3.88 g of the specific polymer IIa obtained in Synthesis Example 1 and 0.58 g of Epicoat 154, which is an epoxy compound, were dissolved in N-methyl-2-pyrrolidone to obtain a solution having a solid concentration of 3.5% by weight. It filtered by the micrometer filter and prepared the liquid crystal aligning agent solution.

A liquid crystal aligning agent is apply | coated with a spinner on this transparent conductive film which consists of an ITO film | membrane provided on one surface of the glass substrate of thickness 1mm, and it dried at 80 degreeC for 1 minute, and then 200 degreeC for 1 hour, and dried film. A coating film having a thickness of 600 angstroms was formed.

 Two board | substrates with a liquid crystal aligning film were produced as mentioned above, the epoxy resin adhesive containing aluminum oxide sphere was apply | coated to the outer periphery of each board | substrate by the screen printing method, and the clearance gap of two board | substrates was made. They were placed face to face through each other, the outer periphery was brought into contact with each other and pressed to cure the adhesive. Liquid crystal was injected and filled into the cell gap partitioned by the adhesive of the surface of the board | substrate and the outer peripheral part, Next, the injection hole was sealed with the epoxy type adhesive agent, and the vertical orientation liquid crystal display element was produced.

The vertical alignment liquid crystal display device fabricated as described above has a good vertical alignment, exhibits a voltage retention of 97%, and a voltage retention rate of 89 when no additives are added. lost. In addition, even when placed under a high humidity of 90% RT, the orientation unevenness generated by moisture absorption was not observed, and showed good results. Therefore, according to the liquid crystal display element produced by the present Example, it was confirmed that it is excellent in the vertical orientation and voltage retention, and a contrast unevenness is not expressed even in high humidity.

Examples 2-9

According to the prescription shown in Table 2, each of the specific polymers II (IIb to IId) obtained in Synthesis Examples 2 to 4 and the specific polymers Ie obtained in Synthesis Example 5 and an epoxy compound were mixed, and a solution of 3.5% similarly to Example 1 was prepared. I did. In this case, in Examples 2 to 5, Compound A was used as the epoxy compound, Compounds B and C were used in Examples 6 and 7, respectively, and in Examples 8 and 9, Compound A was added to 100 parts by weight of the polymer as the epoxy compound. The liquid crystal cell was produced like Example 1 except having set it as 10 parts and 40 parts, respectively, and various evaluation was performed. The results are shown in Table 3 below.

Comparative Examples 1 to 5

According to the prescription shown in Table 2, except that only the specific polymer II (IIb to IId) obtained in Synthesis Examples 1 to 4 and the specific polymer Ie obtained in Synthesis Example 5 were used, a liquid crystal cell was prepared in the same manner as in Example 1 Various evaluations and tests were performed. The results are shown in Table 3 below.

polymer Epoxy compound Amount Example 1 IIa A 20 Example 2 IIb A 20 Example 3 IIc A 20 Example 4 IId A 20 Example 5 IIe A 20 Example 6 IId B 20 Example 7 IId C 20 Example 8 IIa A 10 Example 9 IIa A 40 Comparative Example 1 IIa - 0 Comparative Example 2 IIb - 0 Comparative Example 3 IIc - 0 Comparative Example 4 IId - 0 Comparative Example 5 IIe - 0

※ Addition: Weight part of the additive with respect to 100 weight part of the polymer

A: Epicoat 154

B: Epicoat 1031S

C: ceroxide 2021

Orientation of liquid crystal molecules Moisture resistance test Reliability test Voltage retention rate (%) Example 1 Good Good O.K 97 Example 2 Good Good O.K 97 Example 3 Good Good O.K 96 Example 4 Good Good O.K 96 Example 5 Good Good O.K 96 Example 6 Good Good O.K 95 Example 7 Good Good O.K 96 Example 8 Good Good O.K 96 Example 9 Good Good O.K 95 Comparative Example 1 Good Bad O.K 89 Comparative Example 2 Good Bad O.K 87 Comparative Example 3 Good Bad O.K 88 Comparative Example 4 Good Bad O.K 85 Comparative Example 5 Good Bad O.K 83

According to the liquid crystal aligning agent of the present invention, it is possible to produce a vertically oriented liquid crystal display device which is excellent in vertical alignment property and voltage holding property, and which does not exhibit contrast spots and display defects even when left under high humidity.

The vertically oriented liquid crystal display device of the present invention can be effectively used in various devices, and is used in display devices such as a desk calculator, a wrist watch, a table clock, a counting plate, a word processor, a personal computer, a liquid crystal television, and the like. .

Claims (3)

(A) 100 parts by weight of an aromatic polyamide and / or its imidized polymer obtained by reacting tetracarboxylic dianhydride and a diamine compound, and (B) 0.01-100 weight part of compounds containing 2 or more epoxy groups in a molecule | numerator, The vertically-aligned liquid crystal aligning agent characterized by the above-mentioned. The compound containing at least two epoxy groups in the molecule has at least one member selected from the group consisting of substructures represented by the following formulas (iii), (ii) and (iii): Liquid crystal aligning agent.

(Wherein R represents hydrogen or a monovalent organic group having 1 to 20 carbon atoms, k represents 1 to 3, l represents 1 to 3, m represents 1 to 4, and n represents an integer of 1 to 20) The liquid crystal aligning film formed from the liquid crystal aligning agent of Claim 1 is provided, The vertically-aligned liquid crystal display element characterized by the above-mentioned.