KR20140128228A - Liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display device - Google Patents

Abstract

Provided is a liquid crystal aligning agent by which a highly reliable liquid crystal display device can be produced. The liquid crystal aligning agent includes: at least one polymer (A) selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide; and a multifunctional block isocyanate compound (B-1) having a directional ring.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal alignment material, a liquid crystal alignment film, and a liquid crystal display device,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film and a liquid crystal display element, and more particularly to a technique for improving the reliability of a liquid crystal display element.

Conventionally, various driving methods have been developed as liquid crystal display devices, which have different electrode structures and physical properties of liquid crystal molecules to be used. For example, TN type, STN type, VA type, MVA type, ), An FFS type, and an optical compensation band type (OCB type). These liquid crystal display devices have a liquid crystal alignment film for aligning liquid crystal molecules. As a material of the liquid crystal alignment film, polymers such as polyamic acid, polyimide, polyamic acid ester, polyester, and polyorganosiloxane are used, and in particular, various properties such as heat resistance, mechanical strength, , Polyamic acid and polyimide are generally used.

In recent years, liquid crystal display devices have been used not only in display devices such as personal computers, but also in various types of applications such as liquid crystal televisions, car navigation systems, mobile phones, smart phones, and information displays. In addition, as a liquid crystal display element, a high reliability that can withstand long-term use is required, and various liquid crystal aligning agents have been proposed in order to satisfy such a demand (for example, see Patent Documents 1 and 2). Patent Documents 1 and 2 disclose that a polyimide having a carboxyl group as a polymer component and a polyimide having a primary amino group and a nitrogen-containing aromatic heterocycle and having a primary amino group bonded to an aliphatic hydrocarbon group Discloses a liquid crystal aligning agent containing a primary amine compound.

International Publication No. 2008/013285 International Publication No. 2009/084665

A demand for higher performance of a liquid crystal display element is further increasing. As a liquid crystal alignment film, there is a demand for a liquid crystal alignment film which has less deterioration and deterioration after long-term use than conventional ones and has high reliability that can adequately manifest its performance as a liquid crystal alignment film.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its main object is to provide a liquid crystal aligning agent capable of improving the reliability of a liquid crystal display element. Another object of the present invention is to provide a liquid crystal display device having high reliability.

DISCLOSURE OF THE INVENTION The present inventors have intensively studied in order to achieve the above-described problems of the prior art. As a result, they found that the above problems can be solved by containing a specific compound as an additive component in a liquid crystal aligning agent. It came. Specifically, the following liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display element are provided by the present invention.

According to one aspect of the present invention, there is provided a polyfunctional isocyanate compound (B-1) comprising at least one polymer (A) selected from the group consisting of polyamic acid, polyamic acid ester and polyimide and a polyfunctional block isocyanate compound Based on the total weight of the liquid crystal aligning agent.

In one aspect, the present invention provides a liquid crystal alignment film formed using the liquid crystal aligning agent described above. According to another aspect of the present invention, there is provided a liquid crystal display device including the liquid crystal alignment layer.

According to the liquid crystal aligning agent of the present invention, by containing the above-described compound (B-1) as an additive component, it is possible to form a liquid crystal alignment film capable of obtaining a liquid crystal display device with low voltage- have.

(Mode for carrying out the invention)

Hereinafter, each component contained in the liquid crystal aligning agent of the present invention and other components arbitrarily blended as required will be described.

≪ Polymer (A) >

The liquid crystal aligning agent of the present invention contains, as a polymer component, at least one polymer (A) selected from the group consisting of polyamic acid, polyamic acid ester and polyimide.

[Polyamic acid]

The polyamic acid (hereinafter also referred to as " polyamic acid (A) ") as the polymer (A) in the present invention can be obtained, for example, by reacting a tetracarboxylic acid dianhydride with a diamine.

(Tetracarboxylic acid dianhydride)

Examples of the tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid (A) in the present invention include aliphatic tetracarboxylic acid dianhydride, alicyclic tetracarboxylic acid dianhydride, and aromatic tetracarboxylic dianhydride. . As specific examples thereof,

Examples of the aliphatic tetracarboxylic acid dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride and the like;

As the alicyclic tetracarboxylic acid dianhydride, for example, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4, 5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2- c] furan-1,3-dione, , 5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ (Tetrahydrofuran-2 ', 5'-dione), 5- (2,5-dioxotetrahydro-3 ' 3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2: 3,5: 6-2 anhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-2 anhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane- , 5,8,10-tetraone, cyclohexanetetracarboxylic acid dianhydride, cyclopentanetetracarboxylic acid dianhydride and the like;

As the aromatic tetracarboxylic acid dianhydride, for example, pyromellitic dianhydride and the like;

Tetracarboxylic acid dianhydride described in JP-A-2010-97188, and the like can be used. The tetracarboxylic acid dianhydride may be used singly or in combination of two or more.

The tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid (A) preferably contains an alicyclic tetracarboxylic acid dianhydride in view of good solubility in solvents and transparency. Among them, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -Naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- Furanyl) -naphtho [1,2-c] furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane- 2-anhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride and 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride (Hereinafter also referred to as " specific tetracarboxylic acid dianhydride "), and more preferably at least one selected from the group consisting of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 2,4,6 , 8-tetracarboxybicyclo [3.3.0] octane-2: 4,6,8-2 anhydride, 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, 1,2,4,5-cyclo Hexane tetracarbon More preferably at least one kind of compound selected from the group consisting of acid anhydrides and 1,2,3,4-cyclopentanetetracarboxylic acid dianhydrides (hereinafter also referred to as "specific tetracarboxylic acid dianhydrides") Do.

As the tetracarboxylic acid dianhydride used for the synthesis of the polyamic acid, it is preferable that the specific tetracarboxylic acid dianhydride is contained in an amount of 20 mol% or more based on the total amount of the tetracarboxylic acid dianhydride used in the synthesis, , And more preferably 80 mol% or more.

(Diamine)

Examples of the diamine used in the synthesis of the polyamic acid (A) in the present invention include aliphatic diamines, alicyclic diamines, aromatic diamines, diaminoorganosiloxanes and the like. Specific examples thereof include aliphatic diamines such as meta-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine and the like;

As the alicyclic diamine, for example, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane and the like;

Examples of the aromatic diamine include p-phenylenediamine, 4,4'-diaminophenylmethane, 4,4'-diaminodiphenylsulfide, 1,5-diaminonaphthalene, 2,2'- Diaminobiphenyl, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 2,7-diaminofluorene, 4,4'- Phenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9- ) Phenyl hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '- (p-phenylenediisopropylidene) (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4-bis (4-aminophenoxy) benzene, Diaminopyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl- 6-diaminocarbazole, N-phenyl-3, (4-aminophenyl) -N, N'-dimethylbenzidine, 1,4-bis- (4-aminophenyl) Aminophenyl) -piperazine, 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl- Dihydro-l, 3,3-trimethyl-lH-inden-6-amine, 3,5-diaminobenzoic acid, cholestanyloxy-3,5-diaminobenzene, cholestenyloxy- , 5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, 3,5-diaminobenzoic acid cholestanyl, 3,5-diamino (4-aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 4- (4 (Trifluoromethoxybenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 4- (4'-trifluoromethylbenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 1,1- Bis (4 - ((aminophenyl) Bis (4 - ((aminophenoxy) methyl) phenyl) -4-heptylcyclohexane, 1,1- Methylphenyl) -4-heptylcyclohexane, 1,1-bis (4 - ((aminophenyl) methyl) Diallyl aniline, 4-aminobenzylamine, 3-aminobenzylamine, and the following formula (D-1):

^Wherein X ¹ and X ² each independently represent a single bond, -O-, -COO- or -OCO-, R ¹ and R ² each independently represent a single bond, A is 0 or 1, b is an integer of 0 to 2, c is an integer of 1 to 20, and n is 0 or 1, provided that a and b are both 0 at the same time None);

As the diaminoorganosiloxane, for example, 1,3-bis (3-aminopropyl) -tetramethyldisiloxane and the like;

The diamine described in JP-A-2010-97188 can be used. As other diamines, these may be used singly or in combination of two or more kinds.

Examples of the divalent group represented by "-X ^I - (R ^I -X ^II ) _n -" in the above formula (D-1) include an alkanediyl group having 1 to 3 carbon atoms, * -O-, * -COO- Or * -OC ₂ H ₄ -O- (provided that a bonding hand having "*" attached thereto is bonded to a diaminophenyl group). Specific examples of the group "-C _c H _{2c +1} " include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, n-heptadecyl, n-heptadecyl, n-octadecyl, n-hexadecyl, n-hexadecyl, n-nonadecyl group, and n-eicosyl group. The two amino groups in the diaminophenyl group are preferably in the 2,4-position or 3,5-position with respect to the other groups.

Specific examples of the compound represented by the formula (D-1) include compounds represented by the following formulas (D-1-1) to (D-1-5)

[Molecular Weight Regulator]

In the synthesis of the polyamic acid, the terminal modified polymer may be synthesized by using a suitable molecular weight regulator together with the tetracarboxylic dianhydride and the diamine as described above. By using such a polymer having a terminal modification type, the coating property (printing property) of the liquid crystal aligning agent can be further improved without impairing the effect of the present invention.

Examples of the molecular weight regulator include acid monoanhydrides, monoamine compounds, and monoisocyanate compounds. Specific examples of such acid anhydrides include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride, n-hexadecylsuccinic anhydride and the like of;

As the monoamine compound, for example, aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine and the like; As the monoisocyanate compound, for example, phenyl isocyanate, naphthyl isocyanate and the like; Respectively.

The use ratio of the molecular weight regulator is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, based on 100 parts by weight of the total amount of tetracarboxylic acid dianhydride and diamine to be used.

[Synthesis of polyamic acid]

The ratio of the tetracarboxylic acid dianhydride and the diamine to be used in the synthesis reaction of the polyamic acid in the present invention is such that the ratio of the acid anhydride group of the tetracarboxylic acid dianhydride to the equivalent of 0.2 to 2 equivalents , More preferably from 0.3 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is preferably carried out in an organic solvent. The reaction temperature is preferably -20 ° C to 150 ° C, more preferably 0 ° C to 100 ° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

Examples of the organic solvent include non-protic polar solvents, phenol solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons and the like. Specific examples of these organic solvents include non-protonic polar solvents such as N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N- N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, gamma -butyrolactone, tetramethylurea, hexamethylphosphoric triamide and the like; As the phenolic solvent, for example, phenol, m-cresol, xylenol, halogenated phenol and the like;

Examples of the alcohols include methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether and the like; Examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and the like; Examples of the ester include esters such as ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate, Isoamyl isobutyrate, and the like;

Examples of the ether include 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 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, Tetrahydrofuran, diisopentyl ether and the like;

As the halogenated hydrocarbon, for example, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene and the like; Examples of the hydrocarbons include hexane, heptane, octane, benzene, toluene, xylene and the like; Respectively.

Among these organic solvents, at least one selected from the group consisting of an aprotic polar solvent and a phenol-based solvent (first group of organic solvents), or at least one selected from organic solvents of the first group, It is preferable to use a mixture of at least one member selected from the group consisting of ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons (organic solvents of the second group). In the latter case, the ratio of the organic solvent of the second group is preferably 50% by weight or less, more preferably 40% by weight or less, based on the total amount of the organic solvent of the first group and the organic solvent of the second group By weight, more preferably not more than 30% by weight. The amount (a) of the organic solvent used is preferably such that the total amount (b) of the tetracarboxylic acid dianhydride and the diamine is 0.1 to 50% by weight based on the total amount (a + b) of the reaction solution.

As described above, a reaction solution obtained by dissolving the polyamic acid (A) is obtained. The reaction solution may be provided as it is in the preparation of the liquid crystal aligning agent, or the polyamic acid (A) contained in the reaction solution may be isolated and then provided in the preparation of the liquid crystal aligning agent, or the polyamic acid (A) May be provided later for preparation of the liquid crystal aligning agent. When the polyamic acid (A) is subjected to dehydration ring closure to form polyimide, the reaction solution may be directly supplied to the dehydration ring-closing reaction, or the polyamic acid (A) contained in the reaction solution may be isolated and then subjected to a dehydration ring- , Or the purified polyamic acid (A) may be purified and then subjected to dehydration ring-closing reaction. The polyamic acid (A) can be isolated and purified by a known method.

[Polyamic acid ester]

The polyamic acid ester (hereinafter also referred to as a polyamic acid ester (A)) as the polymer (A) may be obtained by, for example, [I] reacting a polyamic acid (A) obtained by the above synthesis reaction with a hydroxyl group- Containing compound, an epoxy group-containing compound and the like, [II] a method of reacting a tetracarboxylic acid diester with a diamine, [III] a method of reacting a diamine with a tetracarboxylic acid diester dihalide, and the like.

Examples of the hydroxyl group-containing compound used in the method [I] include alcohols such as methanol, ethanol and propanol; Phenols such as phenol and cresol, and the like. Examples of the halide include methyl bromide, ethyl bromide, stearyl bromide, methyl chloride, stearyl chloride, 1,1,1-trifluoro-2-iodoethane and the like, and the epoxy group-containing compound For example, propylene oxide. The tetracarboxylic acid diester used in the method [II] can be obtained, for example, by ring opening tetracarboxylic dianhydride using the above-mentioned alcohols. Further, the tetracarboxylic acid diester dihalide used in the method [III] can be obtained by reacting the tetracarboxylic acid diester obtained as described above with a suitable chlorinating agent such as thionyl chloride. Examples of the diamines used in the methods [II] and [III] include diamines used in the synthesis of the polyamic acid (A). The polyamic acid ester (A) may have only an amide ester structure, or may be a partial esterified product in which an amide structure and an amide ester structure coexist.

[Polyimide]

The polyimide (hereinafter also referred to as " polyimide (A) ") as the polymer (A) can be obtained by subjecting the polyamic acid (A) synthesized as described above to dehydration ring closure and imidization.

The polyimide (A) may be a complete imide cargo which is subjected to dehydration ring closure of all of the arboric acid structure of the polyamic acid (A) which is a precursor thereof, and the dehydration ring closure of only a part of the arboric acid structure, It may be a partially imide cargo. The imidization ratio of the polyimide (A) is preferably 30% or more, more preferably 50 to 99%, and even more preferably 60 to 99%. The imidization rate is a percentage of the ratio of the number of imide ring structures to the sum of the number of amide structure and the number of imide ring structure of polyimide. Here, a part of the imide ring may be an isoimide ring.

The dehydration ring-closure of the polyamic acid (A) is preferably carried out by heating the polyamic acid (A), or by dissolving the polyamic acid (A) in an organic solvent, adding a dehydrating agent and a dehydrating ring- And heating it in accordance with the above-mentioned method. Of these, the latter method is preferable.

In the method of adding the dehydrating agent and the dehydrating ring-closing catalyst to the solution of the polyamic acid (A), an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent to be used is preferably 0.01 to 20 mol based on 1 mol of the acid structure of the polyamic acid (A). As the dehydration ring-closing catalyst, for example, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used. The amount of the dehydration ring-closing catalyst to be used is preferably 0.01 to 10 mol based on 1 mol of the dehydrating agent to be used. Examples of the organic solvent used in the dehydration ring-closure reaction include the organic solvents exemplified for use in the synthesis of the polyamic acid (A). The reaction temperature of the dehydration cyclization reaction is preferably 0 to 180 캜, more preferably 10 to 150 캜. The reaction time is preferably 1.0 to 120 hours, more preferably 2.0 to 30 hours.

In this way, a reaction solution containing the polyimide (A) is obtained. The reaction solution may be directly supplied to the preparation of a liquid crystal aligning agent or may be provided in the preparation of a liquid crystal aligning agent after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution. Alternatively, after the polyimide (A) The polyimide (A) may be provided in the preparation or may be provided in the preparation of the liquid crystal aligning agent after purification of the isolated polyimide (A). These purification operations can be carried out according to a known method. The method of synthesizing the polyimide (A) is not limited to the above. For example, imidization of the polyamic acid ester (A) may be used.

The polyamic acid, the polyamic acid ester and the polyimide as the polymer (A) obtained as described above preferably have a solution viscosity of 10 to 800 mPa · s and a solution viscosity of 15 to 500 mPa · s s of solution viscosity. The solution viscosity (mPa · s) of the polymer (A) is preferably in the range of 1 to 10 moles per 100 parts by weight of the polymer (A) in a good solvent (for example,? -Butyrolactone, Measured at 25 캜 using an E-type rotational viscometer with respect to a polymer solution having a concentration of 10% by weight prepared by using the same.

The weight average molecular weight in terms of polystyrene measured by gel permeation chromatography of the polyamic acid, the polyamic acid ester and the polyimide as the polymer (A) is preferably 500 to 100,000, more preferably 1,000 to 50,000 desirable.

≪ Block isocyanate compound (B) >

Examples of the additive component include a polyfunctional block isocyanate compound (B) (hereinafter, simply referred to as " compound (B) "). Here, the term " block isocyanate compound " refers to a compound obtained by reacting a compound having an isocyanate group (-NCO) (isocyanate compound) with a blocking agent such as a compound having an active hydrogen or an active methylene compound and making the compound inactive at room temperature. The term " active hydrogen " refers to a hydrogen atom bonded to an atom other than a carbon atom, preferably a bond energy lower than the carbon-hydrogen bond of polymethylene.

The compound (B) may be a low-molecular compound obtained by reacting a polyfunctional isocyanate compound with a block agent, or may be a polymer compound obtained by a reaction of a polyisocyanate obtained by polymerizing a polyfunctional isocyanate compound with a block agent . The compound (B) is preferably a low-molecular compound, and examples thereof include compounds represented by the following formula (b-1):

Wherein X ¹ is an n-valent organic group having 1 to 30 carbon atoms, X ² is an organic group having 1 to 30 carbon atoms, and R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms, N is an integer of 2 to 6, provided that plural R ^{1 s} in the formula may be the same or different, and plural X ^{2 s} may be the same or different;

The compound (B) is preferably a multifunctional block isocyanate compound (B-1) having an aromatic ring from the viewpoint of suitably obtaining the effect that the performance of the liquid crystal alignment film hardly deteriorates due to long-term use, Is preferably a compound represented by the following formula (b1-1):

(In the formula (b1-1), X ¹¹ is an n-valent organic group having an aromatic ring; R ¹ , X ² and n have the same meanings as in the formula (b-1).

Examples of the monovalent hydrocarbon group of 1 to 6 carbon atoms represented by R ¹ in the above formula include a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group. Herein, in the present specification, the term "chain hydrocarbon group" means a hydrocarbon group which does not contain a cyclic structure in its main chain and is composed of only a chain structure. However, the chain structure may be linear or branched. The "alicyclic hydrocarbon group" means a hydrocarbon group containing only the structure of an alicyclic hydrocarbon and not containing an aromatic ring structure as the ring structure. However, it need not be composed of only the structure of an alicyclic hydrocarbon, and a part thereof may also have a chain structure. The term "aromatic hydrocarbon group" means a hydrocarbon group having an aromatic ring structure as a ring structure. However, it need not be constituted only of an aromatic ring structure, and a part thereof may contain a chain structure or a structure of an alicyclic hydrocarbon.

As specific examples of R ¹ , chain hydrocarbon groups include alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, propyl, butyl and pentyl groups; An alkenyl group having 1 to 6 carbon atoms such as an ethynyl group, a propenyl group, and a butenyl group; And an alkynyl group having 1 to 6 carbon atoms such as an ethynyl group and a propynyl group. These groups may be linear or branched. Examples of the alicyclic hydrocarbon group include a cyclopentyl group, a cyclohexyl group and the like; Examples of the aromatic hydrocarbon group include a phenyl group and the like; Respectively.

Among these, R ¹ is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. Particularly, when R ¹ is a hydrogen atom, X ² is easily removed from the compound by heat treatment, and the isocyanate group is suitable for regeneration.

Examples of the n-valent organic group having 1 to 30 carbon atoms for X ¹ include a hydrocarbon group such as a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group, or a carbon-carbon bond in the hydrocarbon group, A group formed by introducing a functional group such as -COO-, -CO-, -NHCO-, -S-, or -NH-, or a group having a heterocyclic ring. Each of these groups may have a substituent such as a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), or an alkoxy group.

Examples of the n-chain hydrocarbon group include an alkane having 1 to 30 carbon atoms such as methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, decane, dodecane, a group in which n hydrogen atoms have been removed; Groups in which n hydrogen atoms have been removed from alkenes having 1 to 30 carbon atoms such as ethene, propene, butene and pentene; And groups obtained by removing n hydrogen atoms from alkenes having 1 to 30 carbon atoms such as acetylene and methyl acetylene. These groups may be linear or branched. Examples of the n-valent alicyclic hydrocarbon group include groups obtained by removing n hydrogen atoms from alicyclic hydrocarbons having 3 to 30 carbon atoms such as cyclopropane, cyclopentane, cyclohexane, and methylcyclohexane; Examples of the n-valent aromatic hydrocarbon group include aromatic hydrocarbons having 5 to 30 carbon atoms such as benzene, toluene, xylene, mesitylene, ethylbenzene, biphenyl, diphenylmethane, diphenylethane, naphthalene, Atoms removed; Examples of the n-valent group having a heterocyclic ring include an n-valent group obtained by removing n hydrogen atoms from a heterocyclic ring, an n-valent group consisting of a chain structure or an alicyclic hydrocarbon structure and a heterocyclic structure; Respectively.

X ¹ is preferably an n-valent aromatic hydrocarbon group having 5 to 30 carbon atoms or an n-valent group having a heterocyclic ring in view of enhancing the reactivity with the carboxyl group of the polymer (A) Quot; * -NR ¹ -CO-X ² (wherein * represents a bond with X ¹ ) "in the general formula ( ¹ ) is preferably bonded to an aromatic ring or a heterocyclic ring. It is especially preferred that the aromatic ring is a benzene ring.

X ¹ is preferably an n-valent organic group having an aromatic ring, that is, X ¹¹ , from the viewpoint of increasing the reactivity with the carboxyl group of the polymer (A). Specifically, X ¹ is preferably an n-valent aromatic group having 5 to 30 carbon atoms A hydrocarbon group, or an n-valent group having an aromatic heterocycle. X ^{11 preferably} has 30 or less carbon atoms, preferably 3 to 20 carbon atoms, more preferably 3 to 15 carbon atoms.

The n-valent aromatic hydrocarbon group of 5 to 30 carbon atoms in X ¹ and X ¹¹ is preferably an n-valent group obtained by removing n hydrogen atoms from the ring portion of the aromatic hydrocarbon having 5 to 30 carbon atoms. In this case, a group obtained by removing n hydrogen atoms from the same ring or a group obtained by removing a total of n hydrogen atoms from a plurality of rings may be used.

In the n-valent group having an aromatic heterocyclic ring in X ¹ and X ¹¹ , the aromatic heterocyclic ring is preferably a nitrogen-containing aromatic heterocyclic ring having a nitrogen atom at the ring part. Specific examples thereof include a pyridine ring, a pyrimidine ring, a pyrazine ring, a pyridazine ring and a triazine ring, and more preferably a pyridine ring, a pyrimidine ring or a triazine ring. The number of aromatic heterocyclic rings of X ¹ and X ¹¹ is not particularly limited and may be one or more. The n-valent group having an aromatic heterocyclic ring is preferably an n-valent group obtained by removing n hydrogen atoms from the ring part of the aromatic heterocyclic ring. In this case, a group obtained by removing n hydrogen atoms from the same heterocycle or a group obtained by removing a total of n hydrogen atoms from a plurality of heterocycles may be used.

n is preferably an integer of 2 to 4, more preferably 2 or 3, and particularly preferably 2, from the viewpoint of suitably generating the crosslinking of the polymer (A) and the ease of availability.

As the monovalent organic group having 1 to 30 carbon atoms for X ² , for example, a hydrocarbon group such as a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group, a carbon-carbon bond in the hydrocarbon group, -1, a group in which a functional group such as -O-, -COO-, -CO-, -NHCO-, -S-, or -NH- is introduced at a position adjacent to a carbonyl group. Each of these groups may have a substituent such as a halogen atom (for example, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), or an alkoxy group. Specific examples of the monovalent hydrocarbon group for X ² include the groups exemplified in the description of R ¹ above.

X ² preferably has 1 to 6 carbon atoms and more preferably 1 to 4 carbon atoms in view of reducing the amount of "HX ² " produced by the regeneration of the isocyanate group by heating in the reaction system .

Examples of X ² include groups represented by the following formulas (x2-1) to (x2-7), and the like:

(In the formulas (x2-1) to (x2-7), R ² , R ⁵ , R ⁶ , R ⁷ and R ⁹ are each independently a monovalent hydrocarbon group; R ³ and R ⁴ are each independently , A monovalent hydrocarbon group or a group "-OR ¹⁰ " (wherein R ¹⁰ represents a monovalent hydrocarbon group), R ⁸ is a monovalent aromatic hydrocarbon group, m is an integer of 2 to 11, "*" , Indicating a bonding bond with the carbonyl group).

Specific examples of the monovalent hydrocarbon group of R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁹ and R ¹⁰ include the groups exemplified as the monovalent hydrocarbon group of R ¹ . R ² to R ¹⁰ each preferably have 1 to 30 carbon atoms.

m is preferably an integer of 3 to 8, more preferably an integer of 4 to 6.

X ² is preferably a group represented by the above formula (x2-1) among the above because it has little influence on the film characteristics of desorbed X ² . R ² in X ² is preferably a monovalent hydrocarbon group of 1 to 30 carbon atoms, more preferably a monovalent chain hydrocarbon group of 1 to 30 carbon atoms. The monovalent straight chain hydrocarbon group of R ² preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, in view of reducing the amount of "HX ² " produced in the reaction system during the regeneration of the isocyanate group, More preferably 1 to 4 carbon atoms, particularly preferably an alkyl group having 1 to 4 carbon atoms.

Specific preferred examples of X ² include groups represented by each of the following formulas (x2-1-1) to (x2-7-1), and the like:

(Wherein " * " represents a bonding bond with a carbonyl group).

Specific examples of the compound (B) include compounds represented by the following formulas (b-1-1) to (b-1-11). As the compound (B), one type may be used alone, or two or more types may be used in combination.

The compounding ratio of the compound (B) is preferably 0.1 to 50 parts by weight, more preferably 0.5 to 30 parts by weight, more preferably 0.5 to 30 parts by weight based on 100 parts by weight of the total amount of the polymer component contained in the liquid crystal aligning agent. More preferably 20 parts by weight.

When a film is formed using the liquid crystal aligning agent of the present invention, X ² is dissociated from the compound (B) by heating (post-baking) during film formation to regenerate the isocyanate group and the isocyanate group It is considered that the carboxyl group of the compound (A) reacts to form a crosslinked structure.

The proportion of the block isocyanate group (-NR ¹ -CO-X ² ) in the liquid crystal aligning agent is preferably 0.01 to 1.0 equivalent based on 1 equivalent of the carboxyl group of the polymer (A) in the liquid crystal aligning agent, More preferably 0.1 to 1.0 equivalents.

The compounding ratio of the compound (B-1) is preferably 0.1 to 50 parts by weight, more preferably 0.5 to 30 parts by weight, relative to 100 parts by weight of the total amount of the polymer components contained in the liquid crystal aligning agent, More preferably 1 to 20 parts by weight.

<Other components>

The liquid crystal aligning agent of the present invention may contain other components other than the polymer (A) and the compound (B), if necessary. Such other components include, for example, other polymers other than the polymer (A), a compound having at least one epoxy group in the molecule (hereinafter referred to as "epoxy group-containing compound"), a functional silane compound, and the like have.

[Other Polymers]

The other polymer may be used for improving solution characteristics and electrical properties. Examples of such other polymers include polyorganosiloxanes, polyesters, polyamides, cellulose derivatives, polyacetals, polystyrene derivatives, poly (styrene-phenylmaleimide) derivatives and poly (meth) acrylates .

When the other polymer is added to the liquid crystal aligning agent, the blending ratio thereof is preferably 50% by weight or less, more preferably 0.1 to 40% by weight, further preferably 0.1 to 30% by weight, based on the total amount of the polymer in the composition desirable.

[Epoxy group-containing compound]

The epoxy group-containing compound can be used for improving the adhesion to the substrate surface and electric characteristics in the liquid crystal alignment film. Examples of the epoxy group-containing compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether Diallyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylol propane triglycidyl ether, 2,2-dibromonopentyl glycol di N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N'-tetraglycidyl-4,4'-diaminophenylmethane, N, N-diglycidyl-benzylamine, N, N-diglycidylaminomethylcyclohexane, N, N -Diglycidyl-cyclohexylamine and the like can be preferably used. As other examples of the epoxy group-containing compound, an epoxy group-containing polyorganosiloxane described in International Publication No. 2009/096598 can also be used.

When these epoxy group-containing compounds are added to the liquid crystal aligning agent, the blending ratio thereof is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight per 100 parts by weight of the total amount of the polymers contained in the liquid crystal aligning agent.

[Functional silane compound]

The functional silane compound can be used for the purpose of improving the printing property of the liquid crystal aligning agent. Examples of such a functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2 -Aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxy Silane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-triethoxysilylpropyl triethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 9-tri Methoxysilyl-3,6-diazanonyl acetate, methyl 9-trimethoxysilyl-3,6-diazanonanoate, N-benzyl-3-aminopropyltrimethoxysilane, Trimethoxysilane, glycidoxymethyltrimethoxysilane, 2-glycidoxyethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane and the like, Can.

When these functional silane compounds are added to the liquid crystal aligning agent, the mixing ratio thereof is preferably 2 parts by weight or less, more preferably 0.02 to 0.2 parts by weight based on 100 parts by weight of the total of the polymers.

As other components, a compound having at least one oxetanyl group in the molecule, an antioxidant, and the like may be used.

[menstruum]

The liquid crystal aligning agent of the present invention is preferably a liquid composition comprising the above polymer (A), the block isocyanate compound (B) as an additive component and other components which are optionally used, dispersed or dissolved in a suitable organic solvent It is prepared.

Examples of the organic solvent to be used include organic solvents such as N-methyl-2-pyrrolidone,? -Butyrolactone,? -Butyrolactam, N, N-dimethylformamide, 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- propyl 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, diisobutyl ketone, isoamylphosphate Propionate, isoamyl isobutyrate, di-isopentyl ether, ethylene carbonate, propylene carbonate, and the like. These may be used alone or in combination of two or more.

The solid concentration of the liquid crystal aligning agent of the present invention (the ratio of the total weight of components other than the solvent of the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., Is in the range of 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention is applied to the surface of the substrate as described later, and preferably is heated to form a coating film which becomes a liquid crystal alignment film or a liquid crystal alignment film. At this time, when the solid concentration is less than 1% by weight, the film thickness of the coating film becomes too small, and it becomes difficult to obtain a good liquid crystal alignment film. On the other hand, when the solid concentration exceeds 10% by weight, the film thickness of the coating film becomes excessively large and it becomes difficult to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal aligning agent tends to be increased and the coatability tends to be lowered.

A particularly preferable range of the solid concentration is different depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, in the case of the spinner method, it is particularly preferable that the solid concentration (the ratio of the total weight of the components other than the solvent in the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is in the range of 1.5 to 4.5 wt%. In the case of the printing method, it is particularly preferable to set the solid concentration in the range of 3 to 9% by weight and the solution viscosity in the range of 12 to 50 mPa · s accordingly. In the case of the inkjet method, it is particularly preferable that the solid concentration is in the range of 1 to 5 wt%, and the solution viscosity is in the range of 3 to 15 mPa · s. The temperature for preparing the liquid crystal aligning agent of the present invention is preferably 10 to 50 占 폚, more preferably 20 to 30 占 폚.

<Liquid Crystal Alignment Film and Liquid Crystal Display Device>

The liquid crystal alignment film of the present invention is formed by the liquid crystal aligning agent prepared as described above. Further, the liquid crystal display element of the present invention comprises a liquid crystal alignment film formed using the liquid crystal aligning agent. The driving mode of the liquid crystal display element is not particularly limited, and can be applied to various driving modes such as TN type, STN type, IPS type, FFS type, VA type, MVA type, and PSA type.

The liquid crystal display element of the present invention can be produced, for example, by a method including the following steps (1) to (3). In the step (1), the substrate to be used differs depending on the desired drive mode. Processes (2) and (3) are common to each drive mode.

[Process (1): Formation of coating film]

First, a liquid crystal aligning agent of the present invention is coated on a substrate, and then a coated film is formed on the substrate by heating the coated surface.

(1-1) In the case of producing liquid crystal display devices of TN type, STN type, VA type, MVA type or PSA type, two substrates on which a patterned transparent conductive film is formed are paired, The liquid crystal aligning agent of the present invention is preferably applied by offset printing, spin coating, roll coating, or inkjet printing on the surface of the transparent conductive film. Examples of the substrate include glass such as float glass and soda glass; A transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and poly (alicyclic olefin) can be used. As the transparent conductive film to be formed on one surface of the substrate, an ITO film made of NESA film (a registered trademark of PPG Corporation of the US) or indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) made of tin oxide (SnO ₂ ) . In order to obtain a patterned transparent conductive film, for example, a method of forming a pattern by photoetching after forming a transparent conductive film without a pattern, a method of using a mask having a desired pattern in forming a transparent conductive film, have. In the application of the liquid crystal aligning agent, a functional silane compound, a functional titanium compound or the like is added to the surface of the substrate surface on which the coating film is to be formed in advance in order to improve the adhesion between the substrate surface and the transparent conductive film and the coating film It is also possible to carry out the pre-treatment for applying the coating.

After application of the liquid crystal aligning agent, preheating (prebaking) is preferably performed for the purpose of preventing the flow of the liquid of the applied aligning agent or the like. The prebaking temperature is preferably 30 to 200 캜, more preferably 40 to 150 캜, particularly preferably 40 to 100 캜. The prebaking time is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes. Thereafter, a firing (post-baking) process is carried out for the purpose of completely removing the solvent and for the purpose of thermally modifying the acid structure present in the polymer as required. The firing temperature (post-baking temperature) at this time is preferably 80 to 300 占 폚, more preferably 120 to 250 占 폚. The post baking time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The film thickness of the film thus formed is preferably 0.001 to 1 占 퐉, and more preferably 0.005 to 0.5 占 퐉.

(1-2) In the case of manufacturing an IPS or FFS type liquid crystal display element, the electrode formation surface of the substrate on which the electrode made of the transparent conductive film or the metal film patterned in the comb shape is formed, The liquid crystal aligning agent of the present invention is applied to one side of the substrate, and then each coated side is heated to form a coated film. The preferable thickness of the substrate and the transparent conductive film used, the coating method, the heating conditions after coating, the method of patterning the transparent conductive film or the metal film, the pretreatment of the substrate, and the coating film to be formed are the same as in the above (1-1) Do. As the metal film, for example, a film made of a metal such as chromium can be used.

In both cases (1-1) and (1-2), a coating film to be an alignment film is formed by applying a liquid crystal aligning agent on a substrate and then removing the organic solvent. At this time, when the polymer contained in the liquid crystal aligning agent of the present invention is a polyamic acid, a polyamic acid ester, or an imidized polymer having an imidazole ring structure and an arboric acid structure, the dehydration ring- , Or a more imaged coating film may be used.

[Process (2): rubbing treatment]

When a liquid crystal display element of TN type, STN type, IPS type or FFS type is produced, the coating film formed in the above step (1) is coated with a cloth made of fibers such as nylon, rayon, Rub rubbing treatment is performed. Accordingly, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film. On the other hand, in the case of producing a VA type liquid crystal display device, the coating film formed in the above step (1) can be directly used as a liquid crystal alignment film, but the coating film may be rubbed. Further, it is also possible to subject the rubbed liquid crystal alignment film to a treatment for changing a pretilt angle of a part of the liquid crystal alignment film by irradiating a part of the liquid crystal alignment film with ultraviolet rays or a process for forming a resist film on a part of the surface of the liquid crystal alignment film, After the rubbing treatment is performed in a direction different from the rubbing treatment, a treatment for removing the resist film may be performed so that the liquid crystal alignment film has different liquid crystal aligning ability for each region. In this case, it is possible to improve the visual field characteristic of the obtained liquid crystal display element.

In the case of manufacturing a PSA-type liquid crystal display device, the following step (3) may be carried out using the coating film formed in the above step (1) as it is. However, it is also possible to control the inclination of the liquid crystal molecules, A weak rubbing treatment may be carried out for the purpose of carrying out the present invention.

[Process (3): Construction of liquid crystal cell]

(3-1) A liquid crystal cell is prepared by preparing two substrates on which a liquid crystal alignment film is formed as described above, and arranging liquid crystals between two substrates opposed to each other. To produce a liquid crystal cell, for example, the following two methods can be used. First, the first method is a conventionally known method. In this method, two substrates are opposed to each other via a gap (cell gap) so that the respective liquid crystal alignment films face each other, and the peripheral portions of the two substrates are bonded to each other using a sealant, Liquid crystal is injected and filled in the cell gap defined by the liquid crystal cell, and then the injection port is sealed to manufacture a liquid crystal cell. The second method is a method called ODF (One Drop Fill) method. In this method, for example, an ultraviolet curable sealant is applied to a predetermined place on one of the two substrates on which the liquid crystal alignment film is formed, and liquid crystal is dropped to a predetermined number of places on the liquid crystal alignment film surface The other substrate is bonded so that the liquid crystal alignment film is opposed to the other substrate. Then, the liquid crystal is spread over the entire surface of the substrate, and then the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant, thereby manufacturing a liquid crystal cell. In either case, it is preferable to further heat the liquid crystal cell manufactured as described above to a temperature at which the liquid crystal used has an isotropic phase, and then gradually cool to room temperature to remove the flow alignment at the time of filling the liquid crystal .

As the sealing agent, for example, an epoxy resin containing an aluminum oxide sphere as a curing agent and a spacer can be used. Examples of the liquid crystal include nematic liquid crystals and smectic liquid crystals. Of these, nematic liquid crystals are preferable, and examples thereof include a cypher base liquid crystal, an agar watch liquid crystal, a biphenyl liquid crystal, a phenyl cyclohexane liquid crystal, Based liquid crystal, terphenyl-based liquid crystal, biphenylcyclohexane-based liquid crystal, pyrimidine-based liquid crystal, dioxane-based liquid crystal, bicyclooctane-based liquid crystal, quartz-based liquid crystal and the like. Further, to these liquid crystals, for example, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonanoate and cholesteryl carbonate; Chiral agents such as those sold under the trade names "C-15" and "CB-15" (Merck); p-decyloxybenzylidene-p-amino-2-methylbutyl cinnamate, or the like may be added and used.

(3-2) In the case of manufacturing a PSA type liquid crystal display device, a liquid crystal cell is constructed in the same manner as in (3-1) above, except that a photopolymerizable compound is injected or dropped together with liquid crystal. Thereafter, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates. The voltage to be applied here may be DC or AC of 5 to 50 V, for example. As the light to be irradiated, for example, ultraviolet rays and visible rays including light having a wavelength of 150 to 800 nm can be used, but ultraviolet rays including light having a wavelength of 300 to 400 nm are preferable. As the light source of the irradiation light, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp and an excimer laser can be used. The ultraviolet ray in the above-mentioned preferable wavelength range can be obtained by a means for using the light source together with, for example, a filter diffraction grating or the like. The irradiation dose of light is preferably 1,000 J / m 2 or more and less than 200,000 J / m 2, and more preferably 1,000 to 100,000 J / m 2.

The liquid crystal display element of the present invention can be obtained by bonding a polarizing plate to the outer surface of the liquid crystal cell. As the polarizing plate to be bonded to the outer surface of the liquid crystal cell, a polarizing plate in which a polarizing film called &quot; H film &quot; in which iodine is absorbed while polyvinyl alcohol is oriented in a stretched polyvinyl alcohol is sandwiched by a cellulose acetate protective film or a polarizing plate comprising H film itself . When the coating film is subjected to the rubbing treatment, the two substrates are opposed to each other such that the rubbing directions of the coating films are at a predetermined angle, for example, orthogonal or anti-parallel to each other.

The liquid crystal display element of the present invention can be effectively applied to various devices and can be applied to various devices such as a clock, a portable game, a word processor, a notebook PC, a car navigation system, a camcorder, a PDA, A monitor, a liquid crystal television, and the like.

[Example]

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

In the following Examples and Comparative Examples, the imidization rate of the polyimide in the polymer solution, the solution viscosity of the polymer solution, the weight average molecular weight of the polymer and the epoxy equivalent were measured by the following methods.

[Imidization Rate of Polyimide]

The polyimide solution was poured into pure water, and the obtained precipitate was sufficiently dried under reduced pressure at room temperature, then dissolved in deuterated dimethyl sulfoxide, and ¹ H-NMR was measured at room temperature using tetramethylsilane as a reference material. From the obtained ¹ H-NMR spectrum, the imidization ratio [%] was determined by the following formula (1): &lt; EMI ID =

Imidization rate [%] = {(1-A ¹ ) / (A ² x?)} 100 ... (One)

(In the formula (1), A ¹ is the peak area derived from the proton of the NH group near the chemical shift of 10 ppm, A ² is the peak area derived from the other proton, and? Is the peak area derived from the proton The ratio of the number of other protons to one proton in the NH group).

[Solution viscosity of polymer solution]

The solution viscosity [mPa 占 퐏] of the polymer solution was measured at 25 占 폚 using an E-type rotational viscometer for a solution prepared by using a predetermined solvent and having a polymer concentration of 10% by weight.

[Weight average molecular weight of polymer]

The weight average molecular weight is a polystyrene reduced value measured by gel permeation chromatography under the following conditions.

Column: TSKgelGRCXLII, manufactured by Tosoh Corporation

Solvent: tetrahydrofuran

Temperature: 40 ° C

Pressure: 68kgf / ㎠

[Epoxy equivalent]

The epoxy equivalent was measured by the hydrochloric acid-methyl ethyl ketone method described in JIS C 2105.

&Lt; Synthesis of Polymer (A) >

[Synthesis Example 1: Synthesis of polyimide (PI-1)] [

(0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic dianhydride, 8.6 g (0.08 mol) of p-phenylenediamine as a diamine, and 5 g of 3,5-diaminobenzoic acid cholester 10.5 g (0.02 mol) of Nil were dissolved in 166 g of N-methyl-2-pyrrolidone (NMP) and reacted at 60 DEG C for 6 hours to obtain a solution containing 20 wt% of polyamic acid. A small amount of the obtained polyamic acid solution was collected, and NMP was added thereto to give a solution viscosity of 90 mPa · s as a solution having a polyamic acid concentration of 10% by weight.

Next, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 7 wt%, 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a solvent by a new NMP (by removing pyridine and anhydrous acetic acid used in the dehydration ring-closure reaction out of the system by this operation, the same applies hereinafter), polyimide having an imidization rate of about 68% 1) was obtained in an amount of 26% by weight. A small amount of the obtained polyimide solution was collected, and NMP was added thereto to give a solution viscosity of 45 mPa · s as a solution having a polyimide concentration of 10% by weight.

[Synthesis Example 2: Synthesis of polyimide (PI-2)] [

22.5 g (0.1 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic acid dianhydride, 10.7 g (0.07 mole) of 3,5-diaminobenzoic acid as diamine, (0.015 mol) of diaminobenzene and 6.94 g (0.015 mol) of the compound represented by the above formula (D-1-5) were dissolved in 190 g of NMP and reacted at 60 DEG C for 6 hours to obtain a polyamic acid solution % Solution. A small amount of the obtained polyamic acid solution was collected, and the solution viscosity was measured as a solution having a polyamic acid concentration of 10% by weight by adding NMP, and the solution viscosity was 80 mPa · s.

Next, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 7% by weight, and 15.7 g of pyridine and 20.3 g of acetic anhydride were added and the dehydration ring-closure reaction was carried out at 110 캜 for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a fresh NMP solvent to obtain a solution containing 26% by weight of a polyimide (PI-2) having an imidization rate of about 80%. A small amount of the obtained polyimide solution was collected, and NMP was added to the resulting solution to measure a solution viscosity of 10 wt% as a polyimide solution to give a solution viscosity of 40 mPa · s.

[Synthesis Example 3: Synthesis of polyimide (PI-3)] [

(0.075 mole) of 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4, 6: 8-2 anhydride as the tetracarboxylic acid dianhydride and 1,2,3,4- (0.07 mole) of cyclobutanetetracarboxylic acid dianhydride, 10.7 g (0.07 mole) of 3,5-diaminobenzoic acid as a diamine and 1, 3-diamino-4- {4- [ (0.03 mol) of the compound represented by the formula (D-1-2) was dissolved in 190 g of NMP, and the reaction was carried out at 60 DEG C for 6 hours. To obtain a solution containing 20 wt% of polyamic acid. A small amount of the obtained polyamic acid solution was collected and NMP was added thereto, and the solution viscosity measured as a solution having a polyamic acid concentration of 10 wt% was 85 mPa · s.

Next, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 7 wt%, and 9.5 g of pyridine and 12.3 g of acetic anhydride were added, followed by dehydration ring closure reaction at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with fresh NMP by solvent, to obtain a solution containing 26% by weight of polyimide (PI-3) having an imidization rate of about 65%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto to give a solution viscosity of 45 mPa 으로서 as a solution having a polyimide concentration of 10% by weight.

[Synthesis Example 4: Synthesis of polyimide (PI-4)] [

(0.50 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as a tetracarboxylic acid dianhydride, and 110 g (0.50 mol) of 1,3,3a, 4,5,9b-hexahydro-8- (0.85 mol) of p-phenylenediamine as diamine, 1 g (0.85 mol) of p-phenylenediamine as diamine, 1 g of 2,2'- 25 g (0.040 mol) of 3-bis (3-aminopropyl) tetramethyldisiloxane and 0.1 g of 3,6-bis (4-aminobenzoyloxy) cholestane and 1.4 g ) Was dissolved in 960 g of NMP and reacted at 60 占 폚 for 6 hours to obtain a solution containing polyamic acid. A small amount of the obtained polyamic acid solution was collected and NMP was added thereto, and the solution viscosity was measured as a solution having a polyamic acid concentration of 10 wt%, and the solution viscosity was 60 mPa · s.

Next, 2,700 g of NMP was added to the obtained polyamic acid solution, 390 g of pyridine and 410 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a solvent of fresh? -Butyrolactone to obtain about 2,500 g of a solution containing 15% by weight of polyimide (PI-4) having an imidization rate of about 95%. A small amount of this solution was collected and NMP was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 70 mPa · s.

[Synthesis Example 5: Synthesis of polyimide (PI-5)] [

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 8.6 g (0.08 mol) of p-phenylenediamine as diamine, and 4,4'-diaminophenylmethane 2.0 3.2 g (0.01 mol) of 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl were dissolved in 324 g of NMP and reacted at 60 ° C for 4 hours To obtain a solution containing 10 wt% of polyamic acid.

Subsequently, 360 g of NMP was added to the obtained polyamic acid solution, 39.5 g of pyridine and 30.6 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced with a fresh NMP solvent to obtain a solution containing 10% by weight of a polyimide (PI-5) having an imidization rate of about 93%. The solution viscosity of the obtained polyimide solution measured by taking a small amount of the polyimide solution was 30 mPa · s.

[Synthesis Example 6: Synthesis of polyimide (PI-6)] [

22.4 g (0.1 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride as tetracarboxylic dianhydride, 12.2 g (0.08 mole) of 3,5-diaminobenzoic acid as diamine, (0.02 mol) of diaminobenzene was dissolved in 178 g of NMP, and the reaction was carried out at 60 占 폚 for 6 hours to obtain a solution containing 20% by weight of polyamic acid. A small amount of the obtained polyamic acid solution was collected and NMP was added thereto to obtain a solution viscosity of 80 mPa 으로서 as a solution having a polyamic acid concentration of 10 wt%.

Next, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 7 wt%, 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring-closure reaction, the solvent in the system was replaced with a fresh NMP solvent to obtain a solution containing 26% by weight of a polyimide (PI-6) having an imidization rate of about 65%. A small amount of the obtained polyimide solution was collected, and NMP was added to the resulting solution to measure a solution viscosity of 10 wt% as a polyimide solution to give a solution viscosity of 40 mPa · s.

Synthesis Example 7: Synthesis of polyorganosiloxane (APS-1)

100.0 g of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 500 g of methyl isobutyl ketone and 10.0 g of triethylamine were placed in a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel and a reflux condenser, And mixed at room temperature. Subsequently, 100 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and the reaction was carried out at 80 DEG C for 6 hours while stirring under reflux. After completion of the reaction, the organic layer was taken out and washed with an aqueous 0.2 wt.% Ammonium nitrate solution until the washed water became neutral. Then, the solvent and water were distilled off under reduced pressure to obtain an epoxy group-containing polyorganosiloxane (EPS- 1) as a viscous transparent liquid. As a result of ¹ H-NMR analysis of this epoxy group-containing polyorganosiloxane (EPS-1), a peak based on the epoxy group was obtained near the chemical shift (?) = 3.2 ppm as the theoretical intensity, It was confirmed that the side reaction did not occur. The epoxy group-containing polyorganosiloxane thus obtained had a weight average molecular weight Mw of 3,500 and an epoxy equivalent of 180 g / mol.

Then, 10.0 g of the epoxy group-containing polyorganosiloxane (EPS-1), 30.28 g of methyl isobutyl ketone, 3.98 g of 4-dodecyloxybenzoic acid, and UCAT 18X (trade name, Manufactured by San Aplon Co., Ltd.), and the reaction was carried out with stirring at 100 ° C for 48 hours. After completion of the reaction, ethyl acetate was added to the reaction mixture, which was then washed three times with water. The organic layer was dried over magnesium sulfate and then the solvent was distilled off to obtain 9.0 g of liquid crystal aligning polyorganosiloxane (APS-1) . The weight-average molecular weight Mw of the obtained polymer was 9,900.

&Lt; Example 1 >

[Preparation of liquid crystal aligning agent]

An NMP solution of the compound represented by the formula (b-1-1) as the block isocyanate compound (B) was added to a solution containing the polyimide (PI-1) as the polymer (A) The solution composition was NMP: BC = 50: 50 (weight ratio) and the solid concentration was 6.0 wt%. This solution was filtered using a filter having a pore diameter of 1 탆 to prepare liquid crystal aligning agent (S1).

[Production of liquid crystal cell]

The liquid crystal aligning agent S1 prepared above was applied to the transparent electrode surface of a glass substrate with a transparent electrode made of an ITO film using a liquid crystal alignment film printing machine (manufactured by Nihon Sha Sein Co., Ltd.) After the solvent was removed by heating (prebaking) for 1 minute, the film was heated (post baking) on a hot plate at 210 DEG C for 30 minutes to form a coating film having an average film thickness of 80 nm.

The coating film was subjected to a rubbing treatment with a rubbing machine having rolls wound with a rayon spring at a roll rotation speed of 500 rpm, a stage moving speed of 3 cm / sec, and a hair embroidering length of 0.4 mm to give a liquid crystal aligning ability did. Thereafter, ultrasonic cleaning was performed for 1 minute in ultrapure water, and then the substrate was dried in a 100 占 폚 clean oven for 10 minutes to obtain a substrate having a liquid crystal alignment film. This operation was repeated to obtain a pair of substrates (two substrates) each having a liquid crystal alignment film.

Next, for each of the pair of substrates, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 mu m was applied to the outer edge of the surface having the liquid crystal alignment film, and then the liquid crystal alignment film surface was superimposed And the adhesive was cured. Next, a nematic liquid crystal (MLC-6221 manufactured by Merck Ltd.) was filled between a pair of substrates from a liquid crystal injection port, and then a liquid crystal injection hole was sealed with an acrylic photo-curable adhesive to manufacture a liquid crystal cell.

[Evaluation of reliability of liquid crystal alignment film]

A voltage of 5 V was applied to the liquid crystal cell obtained above in an application time of 60 microseconds and a span of 167 milliseconds, and a voltage maintenance ratio (VHR1) after 167 milliseconds after the application was released was measured. Subsequently, the liquid crystal cell was allowed to stand in an oven at 80 캜 for 200 hours under irradiation with an LED lamp, allowed to stand at room temperature, and naturally cooled to room temperature. After cooling, a voltage of 5 V was applied to the liquid crystal cell at an application time of 60 microseconds and a span of 167 milliseconds, and a voltage maintenance ratio (VHR2) after 167 milliseconds from the application of the release was measured. In addition, "VHR-1" manufactured by Toyo Technica Co., Ltd. was used as the measuring device. The change rate (? VHR) of the VHR at this time was calculated from the following equation (2), and the reliability of the liquid crystal alignment film was evaluated by? VHR.

? VHR [%] = {(VHR1-VHR2) / (VHR1)} 100 ... (2)

In the evaluation, reliability was evaluated as &quot; good (?) &Quot; when the? VHR was less than 0.4% and less than 0.4% (?) &Quot;, and when it was larger than 2.0%, the reliability was evaluated as &quot; bad (X) &quot;. As a result,? VHR = 0.5% in the liquid crystal cell, and the reliability was good.

&Lt; Examples 2 to 9 and Comparative Example 1 >

Liquid crystal aligning agents (S2) to (S9) and (R1) were prepared in the same manner as in Example 1, except that the kind and amount of the polymer component and the additive component used were changed as shown in Table 1 below. The reliability of the liquid crystal cell was evaluated in the same manner as in Example 1 for each of the prepared liquid crystal aligning agents. The results are shown in Table 1 below.

In Table 1, the &quot; amount (amount) &quot; of the polymer component cell indicates the orientation ratio (parts by weight) relative to 100 parts by weight of the total amount of the polymer component contained in the liquid crystal aligning agent. The &quot; addition amount &quot; of the additive chamber represents the orientation ratio (parts by weight) relative to the total amount of 100 parts by weight of the polymer component in the liquid crystal aligning agent. The abbreviations of the additives in Table 1 are as follows.

Add-1: Compound represented by the above formula (b-1-1)

Add-2: Compound represented by the above formula (b-1-2)

Add-3: Compound represented by the following formula (m-1)

As shown in Table 1, in Examples 1 to 9,? VHR was smaller than 1.0 and reliability of the liquid crystal display device was "good". On the other hand, in Comparative Example 1,? VHR was as large as 2.9 and reliability was "poor".

&Lt; Examples 10 to 13 and Comparative Example 2 >

Liquid crystal aligning agents (S10) to (S13) and (R2) were prepared in the same manner as in Example 1, except that the kind and amount of the polymer component and the additive component used were changed as shown in Table 2 below. The reliability of the liquid crystal cell was evaluated in the same manner as in Example 1 for each of the prepared liquid crystal aligning agents. The results are shown in Table 2 below.

In Table 2, the numerical values indicated by the &quot; amount &quot; of the polymer component compartment and the &quot; addition amount &quot; The abbreviations of the additives in Table 2 are as follows.

Add-4: Compound represented by the above formula (b-1-9)

Add-5: Compound represented by the above formula (b-1-10)

Add-6: Compound represented by the following formula (m-2)

Add-7: Compound represented by the above formula (b-1-11)

As shown in Table 2, in Examples 10 to 12, ΔVHR was as small as 0.2% or less, and reliability of the liquid crystal display device was evaluated as "particularly good". In Example 13,? VHR was 1.8%, and reliability was evaluated as &quot; feasible &quot;. On the other hand, in Comparative Example 2, the? VHR was as large as 2.9% and the reliability was "poor".

Claims (13)

A liquid crystal aligning agent comprising at least one polymer (A) selected from the group consisting of polyamic acid, polyamic acid ester and polyimide, and a multifunctional block isocyanate compound (B-1) having an aromatic ring. The method according to claim 1,
Wherein the block isocyanate compound (B-1) is a compound represented by the following formula (b1-1):

(In the formula (b1-1), R ¹ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms, X ¹¹ is an n-valent organic group having an aromatic ring, X ² is an organic group having 1 to 30 carbon atoms N is an integer of 2 to 6, provided that plural R ^{1 s} in the formula may be the same or different, and plural X ^{2 s} may be the same or different; 3. The method of claim 2,
X ¹¹ is an n-valent aromatic hydrocarbon group having 5 to 30 carbon atoms, or an n-valent group having an aromatic heterocycle. 3. The method of claim 2,
X ¹¹ is an n-valent group obtained by removing n hydrogen atoms from a ring portion of an aromatic hydrocarbon having 5 to 30 carbon atoms. 3. The method of claim 2,
X ¹¹ is an n-valent organic group having aromatic heterocycle. 6. The method of claim 5,
X ¹¹ is an n-valent group obtained by removing n hydrogen atoms from a ring part of an aromatic heterocycle. 7. The method according to any one of claims 2 to 6,
Wherein X ² represents a group "* -OR ² " (wherein R ² represents a monovalent hydrocarbon group having 1 to 30 carbon atoms and "*" represents a bond with a carbonyl group). 8. The method of claim 7,
R ² is a monovalent chain hydrocarbon group having 1 to 30 carbon atoms. 7. The method according to any one of claims 2 to 6,
X ¹¹ is an n-valent organic group having 3 to 15 carbon atoms and having an aromatic ring. 7. The method according to any one of claims 1 to 6,
Wherein the content of the block isocyanate compound (B-1) is 0.1 to 50 parts by weight based on 100 parts by weight of the total amount of the polymer components contained in the liquid crystal aligning agent. 7. The method according to any one of claims 1 to 6,
As the polymer (A), 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6,8-2 anhydride , 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, and 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride. And at least one of polyamic acid and polyimide obtained by reacting a tetracarboxylic acid dianhydride containing at least one kind selected from the group consisting of tetracarboxylic dianhydride and diamine. A liquid crystal alignment film formed using the liquid crystal aligning agent according to any one of claims 1 to 6. A liquid crystal display element comprising the liquid crystal alignment film according to claim 12.