KR101813589B1 - Liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display device - Google Patents

Abstract

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal alignment film excellent in electrical characteristics even when continuous driving is performed for a long time under severe environments such as optical stress, heat and humidity, And to provide a liquid crystal alignment film agent which can be formed.
(B) an antioxidant, and (C) a compound having an epoxy group, wherein the polyamic acid is at least one selected from the group consisting of polyamic acid and polyimide obtained by dehydrocondensing the polyamic acid, As a liquid crystal aligning agent. [B] The antioxidant preferably has a group represented by the following formula (1) or (2).

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,

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film and a liquid crystal display element.

Currently, liquid crystal display devices having display modes such as TN (Twisted Nematic) type, STN (Super Twisted Nematic) type, VA (Vertical Alignment) type, IPS (In- Plane Switching) type, OCB (Optical Compensated Bend) It is known. In any of these display modes, the liquid crystal alignment film and the characteristics of the liquid crystal aligning agent serving as the material of the liquid crystal alignment film affect the appearance of the characteristics of the liquid crystal display element in that the alignment state of the liquid crystal molecules is controlled by the liquid crystal alignment film .

As a material of such a liquid crystal aligning agent, resin materials such as polyamic acid, polyimide, polyamide, and polyester are known. Particularly, a liquid crystal alignment film formed of a liquid crystal aligning agent containing polyamic acid or polyimide has heat resistance, mechanical strength, And has been used in many liquid crystal display devices (see Patent Documents 1 to 6).

In recent years, efforts have been made to improve the display quality, reduce power consumption, and the like, including liquid crystal display elements, and the use range of liquid crystal display elements has been expanded. Particularly, the use of a liquid crystal television, which is assumed to be used under conditions in which the use environment such as brightness and driving time is more severe than the conventional liquid crystal display device, has been expanded to establish a conventional CRT television.

However, when a conventional liquid crystal display device comprising a liquid crystal alignment film formed of a liquid crystal aligning agent containing polyamic acid or polyimide is subjected to continuous driving for a long time under a severe environment such as optical stress, heat and humidity, There is a possibility that the display quality is remarkably lowered due to deterioration of the electrical characteristics of the liquid crystal cell.

On the other hand, a substrate on which defects such as pinholes and uneven coating of the coating film are generated in the process of manufacturing a liquid crystal alignment film may be reused as peeling (rewiring) of the coating film. However, when a conventional liquid crystal aligning agent having an epoxy group is used, there is a possibility that the reworkability (peelability) of the liquid crystal alignment layer is lowered by the cross-linking reaction of the epoxy group at the time of baking.

From such a situation, development of a liquid crystal aligning agent capable of forming a liquid crystal alignment film excellent in electrical characteristics even when performing continuous driving for a long time and having excellent reworkability when a defect occurs is desired.

Japanese Patent Application Laid-Open No. 4-153622 Japanese Patent Application Laid-Open No. 60-107020 Japanese Laid-Open Patent Publication No. 56-91277 U.S. Patent No. 5928733 Japanese Laid-Open Patent Publication No. 62-165628 Japanese Patent Application Laid-Open No. 11-258605

SUMMARY OF THE INVENTION The present invention has been made based on the above-described circumstances, and its object is to provide a semiconductor device that maintains good electrical characteristics even when continuous driving is performed for a long time under a severe environment such as optical stress, heat, and humidity, And to provide a liquid crystal aligning agent capable of forming a liquid crystal alignment film excellent in reworkability.

According to an aspect of the present invention,

(A) at least one polymer selected from the group consisting of polyamic acid and polyimide obtained by dehydrocondensing the polyamic acid (hereinafter also referred to as "[A] polymer"),

[B] an antioxidant, and

[C] A compound having an epoxy group (hereinafter also referred to as "[C] compound")

As a liquid crystal aligning agent.

By containing the liquid crystal aligning agent, the [A] polymer, the [B] antioxidant and the [C] compound, it is possible to maintain good electrical characteristics even in the case of continuous driving for a long time under a severe environment such as optical stress, And excellent reworkability can be exhibited.

[B] The antioxidant preferably has a group represented by the following formula (1) or (2)

(In the formula (1)

R ¹ is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, a 1,3-dioxobutyl group or a 1,4-dioxobutyl group; The group represented by the formula (1) is a group in which one hydrogen atom is removed from the alkyl group, aryl group, aralkyl group, 1,3-dioxobutyl group and 1,4-dioxobutyl group represented by R ¹ and becomes a divalent group , Or may form part of the molecular chain;

R ² to R ⁵ are each independently an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 13 carbon atoms;

X ¹ is a single bond, a carbonyl group, * - (CH ₂ ) _n -O-, * -O-, or * -CONH-; Provided that a bonding hand represented by * represents a bonding site with a piperidine ring; N is an integer of 1 to 4;

X ^{2 to} X ⁵ each independently represent a single bond, a carbonyl group, ** -CH ₂ -CO- or ** -CH ₂ -CH (OH) -; Provided that the bonding hands represented by ** represent a bonding site with the piperidine ring).

(In the formula (2), R ⁶ is a hydrocarbon group having 4 to 16 carbon atoms, provided that the hydrocarbon group may have an oxygen atom or a sulfur atom in the carbon skeleton chain; a is an integer of 0 to 3; R ⁷ is a hydrogen atom or a hydrocarbon group having 1 to 16 carbon atoms, provided that when there are plural R ^{7 s} , plural R ^{7 s} may be the same or different).

[B] When the antioxidant has the group of the specific structure, the light resistance and the high temperature and high humidity can be further improved.

The [C] compound is preferably an epoxy group-containing polyorganosiloxane or a monofunctional epoxy compound.

When the [C] compound is an epoxy group-containing polyorganosiloxane or a monofunctional epoxy compound, a liquid crystal alignment film having better workability can be formed even with a composition having an epoxy group.

The polymer [A] is selected from the group consisting of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- Furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5- Dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione and 2,4,6,8-tetracarboxybicyclo [3.3.0] octane- , And 8-2 anhydride, and a diamine with a tetracarboxylic acid dianhydride containing at least one member selected from the group consisting of a tetracarboxylic acid dianhydride and a diamine. By using the specific compound as the acid dianhydride, the light resistance and the high temperature and high humidity resistance can be further improved.

The diamine is preferably selected from the group consisting of 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-5- -1,3,3-trimethyl-1H-inden-6-amine, and the like. By using the specific compound as the diamine, the light resistance and the high temperature and high humidity can be further improved.

A liquid crystal alignment film formed of the liquid crystal aligning agent and a liquid crystal display device having the liquid crystal alignment film are also included in the present invention. The liquid crystal display device can be suitably applied to various apparatuses and can be applied to various devices such as a clock, a portable game, a word processor, a notebook computer, a car navigation system, a camcorder, a portable information terminal, a digital camera, , A liquid crystal television, and the like.

According to the liquid crystal aligning agent of the present invention, it is possible to provide a liquid crystal alignment film excellent in electrical characteristics even when continuous driving is performed for a long time under severe environments such as optical stress, heat and humidity, . Therefore, the liquid crystal display element of the present invention including the liquid crystal alignment film is less deteriorated in display quality and can be effectively applied to various apparatuses. For example, the liquid crystal display element includes a clock, a portable game, a word processor, System, a camcorder, a portable information terminal, a digital camera, a mobile phone, various monitors, a liquid crystal television, and the like.

(Mode for carrying out the invention)

<Liquid Crystal Aligner>

The liquid crystal aligning agent of the present invention contains the [A] polymer, the [B] antioxidant and the [C] compound. By containing the liquid crystal aligning agent, the [A] polymer, the [B] antioxidant and the [C] compound, it is possible to maintain good electrical characteristics even in the case of continuous driving for a long time under a severe environment such as optical stress, And excellent reworkability can be exhibited. The liquid crystal aligning agent may contain other optional components as long as the effect of the present invention is not impaired. Hereinafter, each component will be described in detail.

<[A] Polymer>

[A] The polymer is at least one polymer selected from the group consisting of polyamic acid and polyimide obtained by dehydrating and ring-closing the polyamic acid. The polyamic acid as the [A] polymer is obtained by reacting a tetracarboxylic acid dianhydride with a diamine. Hereinafter, the tetracarboxylic acid dianhydride and the diamine will be described in detail.

[Tetracarboxylic acid dianhydride]

Examples of the tetracarboxylic acid dianhydride include aliphatic tetracarboxylic acid dianhydride, alicyclic tetracarboxylic acid dianhydride, and aromatic tetracarboxylic acid dianhydride. These tetracarboxylic acid dianhydrides may be used alone or in combination of two or more.

Examples of the aliphatic tetracarboxylic acid dianhydride include butane tetracarboxylic dianhydride.

Examples of the alicyclic tetracarboxylic acid dianhydride include 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-3 , 5,8,10-tetraone, and the like.

Examples of the aromatic tetracarboxylic acid dianhydride include pyromellitic dianhydride and the like.

Other tetracarboxylic acid dianhydrides include tetracarboxylic dianhydrides described in JP-A-2010-97188.

As the tetracarboxylic acid dianhydride, it is preferable to include an alicyclic tetracarboxylic acid dianhydride. Further, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- Furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro- -Furanyl) -naphtho [1,2-c] furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane- It is more preferable to include anhydride. Further, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ -Dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) Furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2,4,6,8-2 anhydride. By using the specific compound as the tetracarboxylic dianhydride, the light resistance and the high temperature and high humidity can be further improved.

The particularly preferred 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ 3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ ] Furan-1,3-dione, and 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2,4,6,8-2 anhydride is used as the total tetracarboxylic acid dianhydride , Preferably 10 mol% or more, and more preferably 20 mol% to 90 mol%.

[Diamine]

Examples of diamines include aliphatic diamines, alicyclic diamines, aromatic diamines, diaminoorganosiloxanes, and the like. These diamines may be used alone or in combination of two or more.

The aliphatic diamines include, for example, 1,1-meta-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine and the like.

The aliphatic diamines include, for example, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), and 1,3-bis (aminomethyl) cyclohexane.

Examples of the aromatic diamine include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfide, 1,5-diaminonaphthalene, 2,2'-dimethyl Diaminobiphenyl, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 2,7-diaminofluorene, 4,4'-diamino Diphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9- 4,4'- (m-tert-butylphenyl) hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, Bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4 - diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacrylidine, 3,6-diaminocarbazole, N-methyl- , 6-diaminocarbazole, N- (4-aminophenyl) -N, N'-dimethylbenzidine, 1,4-bis (4-aminophenyl) (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-5-amine, 1- Aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine, 3,5-diaminobenzoic acid, cholestanyloxy-3,5-diaminobenzene, 3, 5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, 3,5-diaminobenzoic acid cholestanyl, 5-diaminobenzoic acid cholestenyl, 3,5-diaminobenzoic acid ranostanyl, 3,6-bis (4-aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) 4- (4'-trifluoromethoxybenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 4- (4'-trifluoromethylbenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 1,1-bis (4 - ((amino (4 - ((aminophenyl) methyl) phenyl) -4-heptylcyclohexane, 1,1-bis ) Methyl) phenyl) -4-heptylcyclohexane, 1,1-bis (4- (aminophenyl) methyl) , N-diallylamine, 4-aminobenzylamine, 3-aminobenzylamine and the compound represented by the following formula (3).

In the above formula (3), R ⁸ is an alkyl group having 1 to 3 carbon atoms, * -O-, * -COO- or * -OCO-. * Is a site bonding with a diaminophenyl group. b is 0 or 1; and c is an integer of 0 to 2. and d is an integer of 1 to 20. The two amino groups in the diaminophenyl group are preferably bonded at the 2,4-position or 3,5-position. It is also preferable that both a and b are not zero.

Examples of the compound represented by the formula (3) include compounds represented by the following formulas.

Examples of the diaminoorganosiloxane include 1,3-bis (3-aminopropyl) -tetramethyldisiloxane and the like. Other diamines include diamines described in JP-A-2010-97188.

As the diamine, it is preferable to include an aromatic diamine. Further, it is also possible to use 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden- 1,3,3-trimethyl-1H-inden-6-amine, and more preferably at least one selected from the group consisting of 1,3,3-trimethyl- By using the specific compound as the diamine, the light resistance and the high temperature and high humidity can be further improved. As a commercially available product of the above-mentioned specific compound, for example, TMDA (manufactured by Nihon Junyaku Co., Ltd.) can be mentioned. TMDA can be obtained by reacting 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden- 1, 3,3-trimethyl-1H-inden-6-amine.

The proportion of the above-mentioned aromatic diamine is preferably 30 mol% or more, more preferably 50 mol% or more, and particularly preferably 80 mol% or more, based on the total diamine. The more preferred 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-5- The use ratio of at least one member selected from the group consisting of dihydro-1,3,3-trimethyl-1H-inden-6-amine is preferably 10 mol% or more, more preferably 20 mol% Mol% is more preferable.

The diamine used in the synthesis of the polyamic acid in the VA type alignment film is preferably at least one selected from the group consisting of dodecaneoxy-2,4-diaminobenzene, tetradecanoxy-2,4-diaminobenzene, pentadecane Oxy-2,4-diaminobenzene, hexadecaneoxy-2,4-diaminobenzene, octadecanoxy-2,4-diaminobenzene, dodecaneoxy- 2,5-diaminobenzene, tetradecanoxy- 2,5-diaminobenzene, pentadecaneoxy-2,5-diaminobenzene, hexadecaneoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, cholestanyloxy-3 , 5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, 3,5- Bis (4-aminophenoxy) cholestane, 3, 6-bis (4-aminobenzoyloxy) cholestane, (4 ' -trifluoromethoxybenzoyloxy) cyclohexyl-3,5- Diaminobenzoate, 1,1-bis (4- (aminophenylmethyl) phenyl) -4-butylcyclohexylcarbodiimide, 4- (4'-trifluoromethylbenzoyloxy) Heptylcyclohexane, 1,1-bis (4- (aminophenoxymethyl) phenyl) -4-heptylcyclohexane, 1,1-bis -Bis (4- (aminophenylmethyl) phenyl) -4- (4-heptylcyclohexyl) cyclohexane, the compound represented by the formula (3) Mol% is more preferable.

[Synthesis method of polyamic acid]

The polyamic acid in the liquid crystal aligning agent is obtained by reacting the tetracarboxylic dianhydride with a diamine. The ratio of the tetracarboxylic acid dianhydride to be used for the synthesis reaction of the polyamic acid is preferably 0.2 equivalents to 2 equivalents, more preferably 0.3 equivalents to 1.2 equivalents, of the acid anhydride group of the tetracarboxylic acid dianhydride relative to 1 equivalent of the amino group contained in the diamine Equivalent is more preferable.

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 hour to 24 hours, more preferably 0.5 hours to 12 hours. Examples of the organic solvent include non-protonic polar solvents, phenol and derivatives thereof, alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons.

Examples of the aprotic polar solvent include N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, , Hexamethylphosphoric triamide, and the like.

Examples of the phenol derivative include 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, and ethylene glycol monomethyl ether.

Examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

Examples of the esters include ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate and diethyl malonate.

Examples of the ether include diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-i-propyl ether, ethylene glycol mono-n- 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 mono Ethyl ether acetate, tetrahydrofuran and the like.

Examples of the halogenated hydrocarbon include dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene and the like.

Examples of the hydrocarbon include hexane, heptane, octane, benzene, toluene, xylene, isoamyl propionate, isoamyl isobutylate, diisopentyl ether and the like.

Among these organic solvents, at least one member selected from the group consisting of an aprotic polar solvent, a phenol and a derivative thereof (first group of organic solvents), or at least one member selected from the first group of organic solvents, 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). The proportion of the organic solvent of the second group is preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less based on the total amount of the organic solvents of the first and second groups Do.

The amount of the organic solvent used is preferably from 0.1% by mass to 50% by mass based on the total amount of the tetracarboxylic acid dianhydride and the diamine.

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

[Method of synthesizing polyimide]

The polyimide which can be contained in the liquid crystal aligning agent is obtained by imidizing the polyamic acid by dehydration ring-closure.

Examples of the tetracarboxylic acid dianhydrides and diamines used for the synthesis of polyimide include tetracarboxylic dianhydrides and diamines which are used in the synthesis of polyamic acids. Desirable tetracarboxylic acid dianhydrides and diamines are used in the same manner as in the synthesis of polyamic acid.

The polyimide may be a completely imidized product obtained by dehydrating and ring closure of the whole of the arboric acid structure of the polyamic acid as a raw material or may be a partially imidized product in which only a part of the arid acid structure is subjected to dehydration ring closure, good. The imidization rate of the polyimide in the liquid crystal aligning agent is preferably 30% or more, more preferably 50% to 99%, and particularly preferably 65% to 99%. The imidization ratio is expressed as 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. At this time, a part of the imide ring may be an isoimide ring. The imidization rate can be found by ¹ H-NMR of polyimide.

In the present specification, the imidization rate can be measured by a method in which the polyimide is sufficiently dried under reduced pressure at room temperature, dissolved in heavy hydride dimethylsulfoxide, and subjected to ¹ H-NMR measurement at room temperature using tetramethylsilane as a reference material (3). &Quot; (3) &quot;

Imidization rate (%) = {1- (A ¹ / A ² ) × α} × 100 (3)

In the formula (3), A ¹ is the peak area derived from the proton of the NH group near 10 ppm of the chemical shift, A ² is the peak area derived from the other proton, and α is the peak area of the polyimide precursor Is the ratio of the number of other protons to one proton in the NH group.

The dehydration ring closure of the polyamic acid for synthesizing the polyimide may be carried out by heating the polyamic acid or by dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring-closing catalyst to the solution, Lt; / RTI &gt; Preferably, the latter method.

Examples of the dehydrating agent include acid anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride. The amount of the dehydrating agent to be used is preferably 0.01 mol to 20 mol per 1 mol of the structural unit of the polyamic acid.

Examples of the dehydration ring-closing catalyst include tertiary amines such as pyridine, collidine, lutidine and triethylamine. The amount of the dehydration ring-closing catalyst to be used is preferably 0.01 mol to 10 mol relative to 1 mol of the dehydrating agent used. Examples of the organic solvent used in the dehydration ring-closure reaction include the organic solvents exemplified for use in the synthesis of polyamic acid. The reaction temperature of the dehydration ring-closure reaction is preferably 0 ° C to 180 ° C, more preferably 10 ° C to 150 ° C. The reaction time is preferably 1.0 hour to 120 hours, more preferably 2.0 hours to 30 hours.

The reaction solution may be directly supplied to the preparation of a liquid crystal aligning agent, may be supplied to the preparation of a liquid crystal aligning agent after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, or may be provided in the preparation of a liquid crystal aligning agent after isolation of the polyimide A good or isolated polyimide may be purified and then added to the preparation of a liquid crystal aligning agent. In order to remove the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, for example, a method such as solvent substitution can be applied. The polyimide can be isolated and purified by a known method.

The polyamic acid or polyimide that the liquid crystal aligning agent may contain may be a polymer of the terminal modified type having a controlled molecular weight. By using a polymer of a terminal modified type, the coating properties and the like of the liquid crystal aligning agent can be further improved without impairing the effect of the present invention. Such a terminal modification type polymer is carried out by adding a molecular weight regulator to the polymerization reaction system when synthesizing a polyamic acid. Examples of the molecular weight regulator include acid monoanhydrides, monoamine compounds, and monoisocyanate compounds.

Examples of the acid anhydrides include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride, and n-hexadecylsuccinic anhydride .

Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, hexadecylamine, n-heptadecylamine, n-octadecylamine, n-octadecylamine, n-octadecylamine, Eicosylamine and the like.

Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

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

The polyamic acid or polyimide obtained as described above preferably has a solution viscosity of 20 mPa · s to 800 mPa · s and a solution viscosity of 30 mPa · s to 500 mPa · s desirable.

The solution viscosity (mPa 占 퐏) of the polymer in the present specification is a value measured at 25 占 폚 using an E-type rotational viscometer for a polymer solution having a concentration of 10 mass% prepared using a predetermined solvent.

<[B] Antioxidant>

[B] The antioxidant is a compound capable of capturing and decomposing peroxyl radicals and hydroperoxides in which energy such as ultraviolet rays or heat is first generated to inhibit oxidation deterioration of the material. When radicals are generated in the polymer [A] due to ultraviolet rays, heat or the like, new radicals or peroxides are generated from the radicals (peroxides generate new radicals), resulting in deterioration of the function of the polymer material. [B] The antioxidant functions as a radical scavenger for negating the radicals thus generated, and as a result, oxidation of the polymer material can be prevented, and deterioration thereof can be suppressed.

[B] The antioxidant preferably has a group represented by the above formula (1) or (2). [B] When the antioxidant has the group of the specific structure, the light resistance and the high temperature and high humidity can be further improved.

In the formula (1), R ¹ represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, a 1,3- Dioxobutyl group. The group represented by the formula (1) is a group in which one hydrogen atom is removed from the alkyl group, aryl group, aralkyl group, 1,3-dioxobutyl group and 1,4-dioxobutyl group represented by R ¹ and becomes a divalent group , Or may form part of the molecular chain. Each of R ² to R ⁵ independently represents an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, or an aralkyl group having 7 to 13 carbon atoms. X ¹ is a single bond, a carbonyl group, * - (CH ₂ ) _n -O-, * -O-, or -CONH-. Provided that a bonding hand represented by * represents a bonding site with a piperidine ring. N is an integer of 1 to 4; X ^{2 to} X ⁵ each independently represent a single bond, a carbonyl group, ** -CH ₂ -CO-, or ** -CH ₂ -CH (OH) -. However, the bonding hands represented by ** represent the bonding sites with the piperidine ring. In the above formula (2), R ⁶ is a hydrocarbon group having 4 to 16 carbon atoms. However, the hydrocarbon group may have an oxygen atom or a sulfur atom in the carbon skeleton chain. a is an integer of 0 to 3; R ⁷ is a hydrogen atom or a hydrocarbon group of 1 to 16 carbon atoms. However, in the case where R ⁷ is plural, plural R ⁷ may be the same or different.

Examples of the alkyl group having 1 to 20 carbon atoms represented by R ¹ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, A heptadecyl group, a heptadecyl group, an octadecyl group, and a nonadecyl group, and the like. Examples of the aryl group having 6 to 20 carbon atoms represented by R ¹ include a phenyl group, a 3-fluorophenyl group, a 3-chlorophenyl group, a 4-chlorophenyl group, a 4-i-propylphenyl group, (4'-t-butylphenyl) -4-quinolinyl group, 2- (2'-thiophenyl) ) -4-quinolinyl group, and the like. Examples of the alkyl group having 1 to 6 carbon atoms represented by R ² to R ⁵ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group and a hexyl group. Examples of the aralkyl group having 7 to 13 carbon atoms represented by R ¹ to R ⁵ include a benzyl group and a phenethyl group. Examples of the aryl group having 6 to 12 carbon atoms represented by R ² to R ⁵ include a phenyl group and the like. Examples of the hydrocarbon group having 4 to 16 carbon atoms which may have an oxygen atom or a sulfur atom in the carbon skeleton chain represented by R ⁶ include a tert-butyl group, a 1-methylpentadecyl group, an octylthiomethyl group, a dodecylthiomethyl group And the like. Examples of the hydrocarbon group having 1 to 16 carbon atoms represented by R ⁷ include a methyl group, a tert-butyl group, a 1-methylpentadecyl group, and an octylthiomethyl group.

[B] As the antioxidant, commercially available products can be used, and examples thereof include phenol antioxidants, amine antioxidants, phosphorus antioxidants, sulfur antioxidants, and blend-based compounds. These [B] antioxidants may be used alone or in combination of two or more.

Examples of commercially available phenolic antioxidants include ADEKASTAB AO-20, AO-30, AO-40, AO-50, AO-60, AO-80, IRGANOX 1035, IRGANOX 1035, IRGANOX 1035, IRGANOX 1135, IRGANOX 1330, IRGANOX 1726, IRGANOX 1425, IRGANOX 1425, IRGANOX 245, IRGANOX 259, IRGANOX 3114, IRGANOX 3114, IRGANOX 3790, IRGANOX 5057, IRGANOX 565 and IRGAMOD 295 (manufactured by BASF Japan K.K.).

Examples of commercial products of the amine antioxidant include Adekastab LA-52, LA-57, LA-63, LA-68, LA-72, LA-77, LA- CHIMASSORB 119, CHIMASSORB 2040, CHIMASSORB 944, TINUVIN 622, TINUVIN 123, TINUVIN 144, and TINUVIN 144 (manufactured by ADEKA Corporation) TINUVIN 765, TINUVIN 770, TINUVIN 111, TINUVIN 783, and TINUVIN 791 (manufactured by BASF Japan K.K.).

PEP-8, copper PEP-36, copper HP-10, copper 2112 (manufactured by ADEKA K.K.), IRGAFOS 168, GSY-P101 IRGAFOS 168, IRGAFOS 12, IRGAFOS 126, IRGAFOS 38 and IRGAFOS P-EPQ (manufactured by BASF Japan Kogyo Co., Ltd.), and the like.

Examples of commercially available products of the sulfur-based antioxidant include Adekustab AO-412, AO-503 (manufactured by ADEKA Corporation), IRGANOX PS 800 and IRGANOX PS 802 (manufactured by BASF Japan Kogyo Co., Ltd.) .

Examples of commercial products of the blend antioxidant include Adekstab A-611, A-612, A-613, AO-37, AO-15, AO-18, (Manufactured by ADEKA K.K.), TINUVIN 111, TINUVIN 783, and TINUVIN 791 (manufactured by BASF Japan K.K.).

Of these commercial products, phenol-based antioxidants and amine-based antioxidants are preferable. The content of [B] antioxidant is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and particularly preferably 0.1 parts by mass to 3 parts by mass, based on 100 parts by mass of the polymer [A] .

&Lt; Compound [C] &gt;

The [C] compound is a compound having an epoxy group. The epoxy group in the present specification refers to a group containing an oxylsilyl group and an oxetanyl group. The [C] compound is not particularly limited as long as it has at least one epoxy group in the molecule, and examples thereof include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl Diethylene glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, 2, 3-hexanediol diglycidyl ether, 2-dibromonopentyl glycol diglycidyl ether, N, N, N ', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylamino Methyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N, N-diglycidylbenzylamine, N, N-diglycidyl - aminomethylcyclohexane, N, N-diglycidyl-cyclohexylamine, glycidoxymethyltrimethoxysilane, glycidoxymethyl 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, (3-ethyloxetane) bis- (3-ethyloxetane), 1,2-bis [(3-ethyl-3-oxetanylmethoxy) (3-ethyl-3-oxetanylmethoxy) methyl] propane, ethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, dicyclopentenylbis Ethyl-3-oxetanylmethyl) ether, triethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, tetraethylene glycol bis (3-ethyl-3-oxetanylmethoxy) butane, 1,6-bis (3-ethyl- Pentaerythritol tris (3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis (3- 3-oxetanylmethyl) ether, dipentaerythritol hexacis (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol pentaquis , Dipentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether, ditrimethylolpropane tetrakis (3-ethyl-3-oxetanylmethyl) ether, 1,4-bis {[ Ethyl] -3-oxetanyl) methoxy] methyl} benzene, di [2- (3- oxetanyl) butyl] ether, 1,4-bis [ Benzene, 1,3-bis [(3-ethyloxetan-3-yl) methoxy] benzene, 1,2-bis [ Bis [(3-ethyl-3-oxetanyl) methoxy] biphenyl, 3,3 ' (3-ethyloxetan-3-yl) methoxy] biphenyl, 2,7-bis [ ] Naphthalene, 1,6-bis [(3-ethyloxetan-3-yl) methoxy] -2,2,3,3,4,4,5,5-octafluorohexyl , 3 (4), 8 (9) -bis [(1-ethyl-3-oxetanyl) methoxy] methyl-tricyclo [5.2.1.0 ^2,6] decane, 4,4'-bis [(1 Ethyl-3-oxetanyl) methyl] thiodibenzene thioether, 2,3-bis [(3-ethyloxetan-3- yl) methoxymethyl] 3-yl) methoxymethyl] -1,3-O-bis [(1-ethyl-3-oxetanyl) methyl] Methyl-propane-1,3-diol, 2-butyl-2-ethyl-1,3-O-bis [3- (3-ethyloxetan- Methyl] -propane-1,3-diol, 1,4-O-bis [(3-ethyloxetan- , 4,6-O-tris [(3-ethyloxetan-3-yl) methyl] cyanuric acid, an etherified product of bisphenol A and 3-ethyl-3-chloromethyloxetane, bisphenol F and 3-ethyl 3-chloromethyloxetane, an etherified product of phenol novolak and 3-ethyl-3-chloromethyloxetane, an etherified product of cresol novolak and 3-ethyl-3- Oxetanyl And silicone alkoxides of 3-ethyl-3-hydroxymethyloxetane.

Examples of commercially available products of the [C] compound include DENACOL EX 611, EX 612, EX 614, EX 622, EX 512, EX 621, EX 411, EX 421, EX 313, EX 321, EX 201, EX 211, EX 212, EX 252, EX 911, EX 941, EX 920, EX 931, EX 111, EX 121 and EX 141 , EX 142, EX 146, EX 192, EX 721, EX 203, EX 711, EX 147, EX 221, EX 150, DENAREX R45 EPT, EX 810 and EX EX 811, EX 850, EX 851, EX 821, EX 830, EX 832, EX 841, EX 861, EX 145 and EX 147 (manufactured by Nagase ChemteX Corporation) (DOX), HQOX, RSOX, CTOX, 4,4'-BPOX, 2,2'-BPOX, TM-BPOX, 2,7-NpDOX, (Manufactured by Toa Kosei Kogyo Co., Ltd.) and ETARNACOLL OXBP (manufactured by Ube Chemical Industries Co., Ltd.), and the like can be given as examples of the catalysts used in the present invention, such as OFH-DOX, NDMOX, TMPTOX, NPGOX, BisAOX, BisFOX, PNOX, CNOX, OX- have.

As another [C] compound, an epoxy group-containing polyorganosiloxane described in WO2009 / 096598 may also be used.

Among these, the [C] compound is preferably an epoxy group-containing polyorganosiloxane or a monofunctional epoxy compound. When the [C] compound is an epoxy group-containing polyorganosiloxane or a monofunctional epoxy compound, a liquid crystal alignment film having better workability can be formed even with a composition having an epoxy group.

As a method for synthesizing an epoxy group-containing polyorganosiloxane, a mixture of a silane compound having an epoxy group or a silane compound having an epoxy group and another silane compound is preferably hydrolyzed in the presence of an appropriate organic solvent, water and a catalyst Or by hydrolysis and condensation.

Examples of the silane compound having an epoxy group include 3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3- 3-glycidyloxypropyldimethylmethoxysilane, 3-glycidyloxypropyldimethylethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2 - (3,4-epoxycyclohexyl) ethyltriethoxysilane, and the like. These may be used alone or in combination of two or more.

Examples of the other silane compounds include tetrachlorosilane, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane, tetra- Butoxysilane, tri-n-butoxysilane, tri-n-butoxysilane, tri-n-butoxysilane, tri-n-butoxysilane, Fluorotris-sec-butoxysilane, fluorotri-n-butoxysilane, fluorotriethoxysilane, fluorotriethoxysilane, fluorotri-n-propoxysilane, N-propoxysilane, methyltri-n-butoxysilane, methyltri-n-butoxysilane, methyltriethoxysilane, methyltriethoxysilane, methyltri-n-propoxysilane, methyltri- -sec-butoxy silane, 2- (trifluoromethyl) ethyl trichlorosilane, 2- (trifluoromethane) Ethyltriethoxysilane, 2- (trifluoromethyl) ethyltriethoxysilane, 2- (trifluoromethyl) ethyltriethoxysilane, 2- (trifluoromethyl) ethyltri- butoxy silane, 2- (trifluoromethyl) ethyl tri-n-butoxy silane, 2- (trifluoromethyl) ethyl tri-sec-butoxysilane, 2- (perfluoro- (Perfluoro-n-hexyl) ethyltrimethoxysilane, 2- (perfluoro-n-hexyl) ethyltriethoxysilane, 2- (Perfluoro-n-hexyl) ethyltri-n-propoxysilane, 2- (perfluoro-n-hexyl) ethyltri- Octyl) ethyltrichlorosilane, 2- (perfluoro-n-octyl) ethyltrimethoxysilane, 2- (perfluoro- (Perfluoro-n-octyl) ethyltri-n-propoxysilane, 2- (perfluoro-n-octyl) ethyltriethoxysilane, 2- Octyl) ethyltri-n-octyl) ethyltri-i-propoxysilane, 2- (perfluoro-n-octyl) ethyltri- butoxysilane, hydroxymethyltrichlorosilane, hydroxymethyltrimethoxysilane, hydroxyethyltrimethoxysilane, hydroxymethyltri-n-propoxysilane, hydroxymethyltri-i-propoxysilane (Meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, (Meth) acryloxypropyltriethoxysilane, 3- (meth) acryloxypropyltri-n-propoxysilane, 3- (meth) acryloxypropyltri- Propyl tri-n-butoxysilane, 3- (meth) acryloxypropyltri-sec-butoxysilane, 3-mercaptopropyltrichlorosilane, 3- 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltri-n-propoxysilane, 3-mercaptopropyltri-i-propoxysilane, 3-mercaptopropyltri-n-butoxy Silane, vinyltriethoxysilane, vinyltriethoxysilane, vinyltriethoxysilane, mercaptomethyltrimethoxysilane, mercaptomethyltriethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriethoxysilane, n-propoxysilane, vinyltri-i-propoxysilane, vinyltri-n-butoxysilane, vinyltri-sec-butoxysilane, allyltrichlorosilane, allyltrimethoxysilane, allyltriethoxysilane N-propoxysilane, allyltri-n-butoxysilane, allyltri-sec-butoxysilane, phenyltrichlorosilane, phenyltrimethoxysilane, phenyl tri N-propoxysilane, phenyltri-i-propoxysilane, phenyltri-n-butoxysilane, phenyltri-sec- Butoxysilane, methyldi-n-butoxysilane, methyldi-n-butoxy silane, methyldi-n-butoxysilane, methyldi-n-butoxysilane, methyldimethoxysilane, methyldiethoxysilane, Propyloxy silane, dimethyl di-n-butoxy silane, dimethyl di-sec-butoxy silane, dimethyl di-n-butoxy silane, dimethyldimethoxy silane, dimethyl diethoxy silane, dimethyl di- (Perfluoro-n-octyl) ethyl] dimethoxysilane, (methyl) [2- (perfluoro-n-octyl) ethyl] dichlorosilane, (Perfluoro-n-octyl) ethyl] diethoxysilane, (methyl) [2- (perfluoro- (methyl) [2- (perfluoro-n-octyl) ethyl] di-n-butoxysilane, (methyl) (3-mercaptopropyl) dichlorosilane, (methyl) ( 3-mercaptopropyl) dimethoxysilane, (methyl) (3-mercaptopropyl) diethoxysilane, (methyl) (3-mercaptopropyl) (Methyl) (3-mercaptopropyl) di-sec-butoxysilane, (methyl) (3-mercaptopropyl) di-n-butoxysilane, (Vinyl) di (meth) acrylate, (methyl) (vinyl) dimethoxysilane, (methyl) (vinyl) diethoxysilane, (Vinyl) di-sec-butoxysilane, divinyldimethoxysilane, divinyldiethoxysilane, divinyldiethoxysilane, divinyl (vinyl) Di-n-propoxysilane, divinyldi-i-propoxysilane, divinyldi-n-butoxysilane, divinyldi-sec-butoxysilane, diphenyldichlorosilane, diphenyldimethoxysilane, di Phenyldiethoxy silane, diphenyl di-n-propoxy silane, diphenyl di-i-propoxy silane, diphenyl di-n- But are not limited to, silane, diphenyl di-sec-butoxysilane, chlorodimethylsilane, methoxydimethylsilane, ethoxydimethylsilane, chlorotrimethylsilane, bromotrimethylsilane, iodotrimethylsilane, methoxytrimethylsilane, ethoxytrimethylsilane, propoxytrimethylsilane, n-butoxytrimethylsilane, sec-butoxytrimethylsilane, t-butoxytrimethylsilane, (chloro) (vinyl) dimethylsilane, (methoxy) ) Silicon atoms such as dimethylsilane, (ethoxy) (vinyl) dimethylsilane, (chloro) (methyl) diphenylsilane, (methoxy) (methyl) diphenylsilane and (ethoxy) And a silane compound having one carbon atom. These may be used alone or in combination of two or more.

The epoxy equivalent of the epoxy group-containing polyorganosiloxane is preferably 50 g / mol to 10,000 g / mol, more preferably 100 g / mol to 10,000 g / mol, and particularly preferably 100 g / mol to 1,000 g / mol. Therefore, in the synthesis of the epoxy group-containing polyorganosiloxane, the use ratio of the silane compound having an epoxy group to the other silane compound is preferably set so that the epoxy equivalence of the resulting polyorganosiloxane is in the above range. The epoxy equivalent of the present invention refers to a value measured by a hydrochloric acid-methyl ethyl ketone method described in JIS C 2105.

Examples of the organic solvent that can be used in the synthesis of the epoxy group-containing polyorganosiloxane include a hydrocarbon compound, a ketone compound, an ester compound, an ether compound, and an alcohol compound. These may be used alone or in combination of two or more.

Examples of the hydrocarbon compound include toluene, xylene, and the like. Examples of the ketone compound include methyl ethyl ketone, methyl isobutyl ketone, methyl n-amyl ketone, diethyl ketone, and cyclohexanone. Examples of the ester compound include ethyl acetate, n-butyl acetate, i-amyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, and ethyl lactate. Examples of the ether compound include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, dioxane and the like. Examples of the alcohol compound include 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n- , Propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether and the like.

The amount of the organic solvent to be used is preferably 10 parts by mass to 10,000 parts by mass, more preferably 50 parts by mass to 1,000 parts by mass, per 100 parts by mass of the total silane compound.

The amount of water to be used when preparing the epoxy group-containing polyorganosiloxane is preferably 0.5 to 1 mole times, more preferably 1 to 30 times as much as the total silane compound.

The hydrolysis or hydrolytic condensation reaction in the synthesis of the epoxy group-containing polyorganosiloxane can be carried out by dissolving an epoxy group-containing silane compound and, if necessary, other silane compounds in an organic solvent, mixing the solution with an organic base and water For example, an oil bath or the like.

The heating temperature in the hydrolysis-condensation reaction is preferably 130 占 폚 or lower, more preferably 40 占 폚 to 100 占 폚. The heating time is preferably 0.5 to 12 hours, more preferably 1 to 8 hours. During the heating, the mixed solution may be stirred or refluxed.

After completion of the reaction, it is preferable to wash the organic solvent layer collected from the reaction solution with water. At the time of cleaning, it is preferable to wash with a water containing a small amount of salt, for example, an aqueous solution of ammonium nitrate of about 0.2 mass% from the viewpoint of facilitating the cleaning operation. The washing is carried out until the water layer after washing becomes neutral, and then the organic solvent layer is dried with a desiccant such as anhydrous calcium sulfate and molecular sieves, if necessary, and then the solvent is removed to obtain a desired epoxy group- containing polyorganosiloxane .

A commercially available product may be used as the epoxy group-containing polyorganosiloxane. Examples of such commercially available products include DMS-E01, DMS-E12, DMS-E21 and EMS-32 (manufactured by Chisso Corporation).

The weight average molecular weight (Mw) of the epoxy group-containing polyorganosiloxane in terms of polystyrene measured by gel permeation chromatography is preferably 500 to 100,000, more preferably 1,000 to 10,000. In the present specification, Mw is a polystyrene-reduced value measured by gel permeation chromatography of the following specifications.

Column: TSK-GEL manufactured by Toso Corporation

Solvent: tetrahydrofuran

Column temperature: 40 DEG C

Pressure: 80kgf / ㎠

The content of the [C] compound is preferably 40 parts by mass or less, more preferably 1 part by mass to 30 parts by mass or less based on 100 parts by mass of the polymer [A].

<Optional ingredients>

The liquid crystal aligning agent may contain, in addition to the [A] polymer, the [B] antioxidant and the [C] compound, other polymers other than the polymer [A], a functional silane compound &Lt; / RTI &gt; These optional components may be used alone or in combination of two or more. Hereinafter, each component will be described in detail.

[Other Polymers]

Other polymers may be used to improve solution properties and electrical properties. Examples of the other polymer include polyamic acid ester, polyester, polyamide, polysiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene-phenylmaleimide) derivative and poly (meth) acrylate. The content of the other polymer can be appropriately determined in accordance with the purpose.

[Functional silane compound]

The functional silane compound may be contained from the viewpoint of further improving the printability of the liquid crystal aligning agent. Examples of the 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-ureidopropyltriethoxysilane , N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxy Silane triethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl- 6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N- Aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N- Bis (oxyethylene) -3-aminopropyltriethoxysilane, and the like. The use ratio of the functional silane compound is preferably 2 parts by mass or less, more preferably 0.1 parts by mass to 1 part by mass, relative to 100 parts by mass of the [A] polymer.

&Lt; Preparation method of liquid crystal aligning agent &gt;

The liquid crystal aligning agent is prepared as a solution-like composition in which the above-mentioned [A] polymer, [B] antioxidant and [C] compound and, if necessary, optional components are dissolved in an organic solvent.

Examples of the organic solvent include N-methyl-2-pyrrolidone,? -Butyrolactone,? -Butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, Methyl-2-pentanone, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono- Ethylene glycol mono-i-propyl ether, ethylene glycol mono-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, Glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, Iso-amyl butyrate may be mentioned, 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 (the ratio of the total mass of the components excluding the organic solvent in the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., To 10% by mass. When the liquid crystal aligning agent is applied to the surface of the substrate and the organic solvent is removed to form a coating film to be a liquid crystal alignment film, when the solid concentration is less than 1% by mass, the film thickness of the coating film becomes excessively small to obtain a good liquid crystal alignment film On the other hand, when the solid concentration exceeds 10% by mass, the film thickness of the coating film becomes excessively large, which makes it difficult to obtain an equally good liquid crystal alignment film. In addition, the viscosity of the liquid crystal aligning agent is increased, May fall.

More preferably, the solid concentration range differs depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, in the case of using the spinner method, a range of 1.5% by mass to 4.5% by mass is preferable. In the case of the printing method, it is preferably in the range of 3 mass% to 9 mass%, and the solution viscosity is preferably in the range of 12 mPa · s to 50 mPa · s. In the case of the ink-jet method, the viscosity is preferably in the range of 1 mass% to 5 mass%, and the solution viscosity is preferably in the range of 3 mPa · s to 50 mPa · s.

The temperature for preparing the liquid crystal aligning agent is preferably 10 ° C to 50 ° C, more preferably 20 ° C to 30 ° C.

&Lt; Method of forming liquid crystal alignment film and method of manufacturing liquid crystal display element &gt;

A liquid crystal alignment film formed of the liquid crystal aligning agent and a liquid crystal display device having the liquid crystal alignment film are also included in the present invention. The liquid crystal display device can be suitably applied to various apparatuses and can be applied to various devices such as a clock, a portable game, a word processor, a notebook computer, a car navigation system, a camcorder, a portable information terminal, a digital camera, , A liquid crystal television, and the like.

The liquid crystal alignment film of the present invention is formed on a substrate by applying the liquid crystal aligning agent on the substrate and then heating the coated surface. Further, the liquid crystal display element of the present invention comprises the liquid crystal alignment film. Hereinafter, a method of forming the liquid crystal alignment film and a method of manufacturing the liquid crystal display element will be described in detail.

(1-1)

In the case of manufacturing a TN type, STN type or VA type liquid crystal display device, two substrates on which a patterned transparent conductive film is formed are paired, and the liquid crystal aligning agent of the present invention is applied on each transparent conductive film- Preferably by an offset printing method, a spin coating method, or an ink jet printing method, and then each coating surface is heated to form a coated 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 alicyclic olefin can be used. Examples of the transparent conductive film formed on one surface of the substrate include a NESA film (registered trademark, manufactured by PPG Corporation, USA) made of tin oxide (SnO ₂ ), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) Can be used.

As a method for obtaining a patterned transparent conductive film, there are, for example, a method of forming a pattern by photoetching after forming a patternless transparent conductive film, a method of using a mask having a desired pattern in forming a transparent conductive film, . A functional silane compound, a functional titanium compound, or the like may be added in advance to the surface of the substrate on which the coating film is formed in order to improve the adhesion between the substrate surface and the transparent conductive film and the coating film at the time of application of the liquid crystal aligning agent It is also possible to carry out the pre-treatment for applying the coating.

After the application of the liquid crystal aligning agent, preheating (prebaking) is preferably performed for the purpose of preventing the flow of the liquid or the like. The prebaking temperature is preferably 30 to 200 캜, more preferably 40 to 150 캜, and particularly preferably 40 to 100 캜. The prebaking time is preferably 0.25 minutes to 10 minutes, more preferably 0.5 minutes to 5 minutes.

Next, baking (post baking) is carried out for the purpose of completely removing the solvent and, if necessary, thermally imidizing the polyamic acid. The post-baking temperature is preferably 80 ° C to 300 ° C, more preferably 120 ° C to 250 ° C. The post baking time is preferably 5 minutes to 200 minutes, more preferably 10 minutes to 100 minutes. The film thickness of the formed coating film is preferably 0.001 to 1 mu m, more preferably 0.005 to 0.5 mu m.

(1-2)

In the case of manufacturing an IPS liquid crystal display device, the liquid crystal aligning agent of the present invention is preferably applied to a conductive film forming surface of a substrate on which a transparent conductive film patterned in a comb shape is formed and a surface of a counter substrate on which a conductive film is not formed Is applied by the offset printing method, the spin coating method or the ink jet printing method, respectively, and then the coating surfaces are formed by heating the respective coated surfaces. The substrate and the material of the transparent conductive film, the method of patterning the transparent conductive film, the pretreatment of the substrate, and the heating method after applying the liquid crystal aligning agent are the same as those of the above (1-1). The preferable film thickness of the formed coating film is the same as that of the above (1-1).

(2) When the liquid crystal display element produced by the method of the present invention is a VA type liquid crystal display element, the coating film formed as described above can be used as it is as a liquid crystal alignment film, It may be provided for use after it is done. On the other hand, in the case of manufacturing a liquid crystal display device other than VA type, a coating film formed as described above is subjected to rubbing treatment to form a liquid crystal alignment film.

The rubbing treatment can be performed by rubbing the coating film surface formed as described above in a predetermined direction with a roll formed of a fiber such as nylon, rayon, or cotton, for example. Accordingly, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film. Further, with respect to the liquid crystal alignment film formed as described above, a part of the liquid crystal alignment film as shown in, for example, Japanese Unexamined Patent Application Publication No. 6-222366 or Japanese Unexamined Patent Application Publication No. 6-281937 is irradiated with ultraviolet rays to form a liquid crystal alignment film After a resist film is formed on a part of the surface of the liquid crystal alignment film as shown in Japanese Unexamined Patent Application Publication No. 5-107544 and the rubbing process is performed in a direction different from the rubbing process, It is possible to improve the visual field characteristics of the obtained liquid crystal display element by performing a process of removing the film and making the liquid crystal alignment film have different liquid crystal aligning ability for each region.

(3) Two substrates on which the liquid crystal alignment film is formed are prepared, and the liquid crystal is arranged between the two substrates arranged opposite to each other to manufacture a liquid crystal cell. Here, 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. For example, the following two methods can be used to manufacture the liquid crystal cell.

As a first method, a conventionally known method is as follows. First, two substrates are opposed to each other via a gap (cell gap) so that the respective liquid crystal alignment films face each other, and a peripheral portion of the two substrates is sealed And the liquid crystal is injected and filled in the cell gap defined by the surface of the substrate and the sealant, and then the injection port is sealed, whereby the liquid crystal cell can be manufactured.

As a second method, a method called an ODF (One Drop Fill) method is used in which a sealing agent of, for example, an ultraviolet light curing property is applied to a predetermined place on one of the two substrates on which a liquid crystal alignment film is formed, The liquid crystal is dropped on a predetermined number of places on the liquid crystal alignment film and then the other substrate is bonded so that the liquid crystal alignment film is opposed to the liquid crystal alignment film and the liquid crystal is extended to the entire surface of the substrate, And the sealing agent is cured by irradiating the liquid crystal cell.

Regardless of the method, the liquid crystal cell manufactured as described above is heated to a temperature at which the liquid crystal used additionally takes an isotropic phase, and then gradually cooled to room temperature to obtain a liquid crystal cell having a flow orientation Is preferably removed. Then, the polarizing plate is bonded to the outer surface of the liquid crystal cell to obtain the liquid crystal display element.

As the sealing agent, for example, an epoxy resin containing an aluminum oxide sphere as a spacer and a curing agent can be given. Examples of the liquid crystal include a nematic liquid crystal and a smectic liquid crystal. Of these, a nematic liquid crystal is preferable. In the VA type liquid crystal cell, a nematic liquid crystal having a negative dielectric anisotropy is preferable. Examples of such a liquid crystal include a dicyanobenzene-based liquid crystal, a pyridazine-based liquid crystal, a cypher base-based liquid crystal, an agar watch liquid crystal, a biphenyl-based liquid crystal, and a phenylcyclohexane-based liquid crystal. In the case of a TN type liquid crystal cell or an STN type liquid crystal cell, a nematic liquid crystal having positive dielectric anisotropy is preferable. Examples of such liquid crystal include biphenyl-based liquid crystal, phenylcyclohexane-based liquid crystal, ester-based liquid crystal, terphenyl-based liquid crystal, biphenylcyclohexane-based liquid crystal, pyrimidine-based liquid crystal, dioxane- Semi-liquid crystal and the like. In addition, a key as commercially available as a cholesteric liquid crystal (C-15, CB-15 manufactured by Merck Ltd.) such as cholesteryl chloride, cholesteryl nonoate and cholesteryl carbonate, Lalje; p-decyloxybenzylidene-p-amino-2-methylbutyl cinnamate, and the like.

As the polarizing plate to be bonded to the outer surface of the liquid crystal cell, a polarizing plate called a "H film" in which iodine is absorbed while polyvinyl alcohol is oriented in a stretched state, a polarizing plate sandwiched by a cellulose acetate protective film or a H film itself And a polarizing plate.

[Example]

Hereinafter, the present invention will be described in detail on the basis of examples, but the present invention is not limitedly interpreted based on the description of this example.

<Synthesis of [A] Polymer>

[Synthesis Example 1]

22.4 g (0.1 mole) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride (TCA) as tetracarboxylic dianhydride and 2.6 g (0.02 mole) of p-phenylenediamine (PDA) (0.02 mole) of diaminobenzoic acid cholestanyl (HCDA) and 9.1 g (0.06 mole) of 3,5-diaminobenzoic acid (DAB) were dissolved in 176 g of N-methyl-2-pyrrolidone , And the reaction was carried out at 60 DEG C for 6 hours to obtain a solution containing 10 mass% of polyamic acid. The solution viscosity of the obtained polyamic acid solution was 102 mPa 占 퐏. Then, 410 g of NMP was added to the obtained polyamic acid solution, 7.9 g of pyridine and 10.2 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 fresh NMP (pyridine and anhydrous acetic acid used in the dehydration ring closure reaction were removed out of the system) to obtain 15 mass% of a polyimide (A-1) having an imidization rate of about 47% . A small amount of the polyimide solution thus obtained was collected, and NMP was added thereto to obtain a solution viscosity of 56 mPa 으로서 as a solution having a polyimide concentration of 10 mass%.

[Synthesis Example 2]

(0.1 mole) of TCA as tetracarboxylic dianhydride and 3.9 g (0.02 mole) of 4,4'-diaminodiphenylmethane (DDM) as diamine, 5.2 g (0.01 mole) of HCDA, 4.9 g (0.01 mole) of 2,4-diaminobenzene (HCODA) and 9.1 g (0.06 mole) of DAB were dissolved in 182 g of NMP and reacted at 60 DEG C for 6 hours to obtain a solution containing 10 mass% . The solution viscosity of the obtained polyamic acid solution was 117 mPa s. Then, 423 g of NMP was added to the obtained polyamic acid solution, and 10.2 g of pyridine and 13.2 g of acetic anhydride were added, followed by dehydration ring-closure reaction 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 15 mass% of polyimide (A-2) having an imidization rate of about 67%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto to obtain a solution viscosity of 70 mPa 으로서 as a solution having a polyimide concentration of 10 mass%.

[Synthesis Example 3]

17.9 g (0.08 mole) of TCA as tetracarboxylic dianhydride and 1, 3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) (0.02 mole) of [1,2-c] furan-1,3-dione (TDA) and 2.2 g (0.02 mole) of PDA as diamine, 10.4 g (0.02 mole) Was dissolved in 182 g of NMP and the reaction was carried out at 60 占 폚 for 6 hours to obtain a solution containing 10 mass% of polyamic acid. The solution viscosity of the obtained polyamic acid solution was 99 mPa.. Next, 423 g of NMP was added to the obtained polyamic acid solution, 7.9 g of pyridine and 10.2 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 fresh NMP by solvent replacement to obtain a solution containing 15 mass% of polyimide (A-3) having an imidization rate of about 51%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto to obtain a solution viscosity of 55 mPa 으로서 as a solution having a polyimide concentration of 10 mass%.

[Synthesis Example 4]

18.0 g (0.08 mole) of TCA as tetracarboxylic dianhydride and 18.0 g (0.08 mole) of 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3- ) -Naphtho [1,2-c] furan-1,3-dione (MTDA) and 2.2 g (0.02 mol) of PDA as diamine, 10.5 g (0.02 mol) of HCDA and 9.2 g (0.06 mol) was dissolved in 185 g of NMP, and the reaction was carried out at 60 DEG C for 6 hours to obtain a solution containing 10 mass% of polyamic acid. The solution viscosity of the obtained polyamic acid solution was 92 mPa · s. Then, 429 g of NMP was added to the obtained polyamic acid solution, 8.0 g of pyridine and 10.3 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 fresh NMP by solvent replacement to obtain a solution containing 15 mass% of polyimide (A-4) having an imidization rate of about 48%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto. The solution viscosity was measured as a solution having a polyimide concentration of 10 mass%, and the solution viscosity was 50 mPa 占 퐏.

[Synthesis Example 5]

18.0 g (0.08 mol) of TCA as tetracarboxylic dianhydride and 5.0 g (0.02 mol) of 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2,4,6,8-2 anhydride (BODA) (0.02 mole) of PDA as a diamine, 10.5 g (0.02 mole) of HCDA and 9.2 g (0.06 mole) of DAB as a diamine were dissolved in 179 g of NMP and reacted at 60 ° C for 6 hours to obtain 10 mass % Solution. The solution viscosity of the obtained polyamic acid solution was 81 mPa s. Subsequently, 416 g of NMP was added to the obtained polyamic acid solution, 7.9 g of pyridine and 10.2 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 15 mass% of polyimide (A-5) having an imidization rate of about 50%. A small amount of the obtained polyimide solution was collected, and NMP was added to the solution to measure a solution viscosity of the polyimide solution of 10 mass%, and the solution viscosity was 42 mPa 占 퐏.

[Synthesis Example 6]

(0.1 mol) of TCA as tetracarboxylic dianhydride, and 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden- 10.7 g (0.04 mol) of a mixture of (TMDA), - (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H- inden- 6.1 g (0.04 mol) of DAB was dissolved in 199 g of NMP, and the reaction was carried out at 60 DEG C for 6 hours to obtain a solution containing 10 mass% of polyamic acid. The solution viscosity of the obtained polyamic acid solution was 80 mPa · s. Subsequently, 462 g of NMP was added to the obtained polyamic acid solution, 7.9 g of pyridine and 10.2 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 15 mass% of polyimide (A-6) having an imidization rate of about 44%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto to obtain a solution viscosity of 66 mPa 으로서 as a solution having a polyimide concentration of 10 mass%.

[Synthesis Example 7]

(0.02 mole) of TCA and 6.0 g (0.02 mole) of TDA as tetracarboxylic dianhydride and 5.3 g (0.02 mole) of TMDA as diamine, 10.5 g (0.02 mole) of HCDA and 9.2 g And the reaction was carried out at 60 占 폚 for 6 hours to obtain a solution containing 10 mass% of polyamic acid. The solution viscosity of the obtained polyamic acid solution was 84 mPa · s. Subsequently, 455 g of NMP was added to the obtained polyamic acid solution, 7.9 g of pyridine and 10.2 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 15 mass% of polyimide (A-7) having an imidization rate of about 49%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto to obtain a solution viscosity of 52 mPa 으로서 as a solution having a polyimide concentration of 10 mass%.

[Synthesis Example 8]

(0.02 mole) of TCA and 6.3 g (0.02 mole) of MTDA as tetracarboxylic dianhydride and 5.3 g (0.02 mole) of TMDA as diamine, 10.4 g (0.02 mole) of HCDA and 9.1 g And the reaction was carried out at 60 占 폚 for 6 hours to obtain a solution containing 10 mass% of polyamic acid. The solution viscosity of the obtained polyamic acid solution was 75 mPa · s. Subsequently, 455 g of NMP was added to the obtained polyamic acid solution, 7.9 g of pyridine and 10.2 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 15 mass% of polyimide (A-8) having an imidization rate of about 47%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto to obtain a solution viscosity of a polyimide concentration of 10 mass%, and the solution viscosity was 49 mPa 占 퐏.

[Synthesis Example 9]

(0.08 mole) of TCA and 5.0 g (0.02 mole) of BODA as tetracarboxylic dianhydride and 5.3 g (0.02 mole) of TMDA as diamine, 10.4 g (0.02 mole) of HCDA and 9.1 g , And the reaction was carried out at 60 占 폚 for 6 hours to obtain a solution containing 10 mass% of polyamic acid. The solution viscosity of the obtained polyamic acid solution was 85 mPa 占 퐏. Next, 442 g of NMP was added to the obtained polyamic acid solution, 7.9 g of pyridine and 10.2 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 15 mass% of polyimide (A-9) having an imidization rate of about 56%. A small amount of the obtained polyimide solution was collected, and NMP was added thereto. The solution viscosity was measured as a solution having a polyimide concentration of 10 mass%, and the solution viscosity was 50 mPa 占 퐏.

<Synthesis of [C] compound>

[Synthesis Example 10]

34.5 g of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 34.5 g of methyl isobutyl ketone and 3.45 g of triethylamine were placed in a reactor equipped with a stirrer, a thermometer, a dropping funnel and a reflux condenser, And mixed at room temperature. Then, 27.6 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 a 0.2 g mass% ammonium nitrate aqueous solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure to obtain a viscous organopolysiloxane solution. As a result of ¹ H-NMR analysis of the organopolysiloxane, it was confirmed that a peak based on the epoxy group was obtained in the vicinity of the chemical shift (?) = 3.2 ppm as the theoretical intensity, and no side reaction of the epoxy group occurred during the reaction . The polyorganosiloxane had an Mw of 3,000 and an epoxy equivalent of 185 g / mol.

7.3 g of the obtained polyorganosiloxane, 41.6 g of methyl isobutyl ketone, 3.0 g of 4-octyloxybenzoic acid and 0.7 g of tetrabutylammonium bromide as a catalyst were placed in a 200-mL three-necked flask, and reacted at 100 DEG C for 8 hours with stirring . After completion of the reaction, ethyl acetate was added to the reaction mixture, which was then washed with water three times. The organic layer was dried over magnesium sulfate and then the solvent was distilled off to obtain 10.1 g of an epoxy group-containing polyorganosiloxane C-4. The Mw of C-4 was 8,000.

[Synthesis Example 11]

In Synthesis Example 10, 7.7 g of the polyorganosiloxane, 3.5 g of 4'-pentyl-1,1'-bicyclohexyl-4-carbonic acid instead of 4-octyloxybenzoic acid, 4.0 g of tetrabutylammonium bromide Was changed to 0.8 g to obtain 10.9 g of an epoxy group-containing polyorganosiloxane C-7. The Mw of C-7 was 8,500.

&Lt; Preparation of liquid crystal aligning agent &

The antioxidant [B] and other [C] compounds used in the preparation of each liquid crystal aligning agent are as follows.

<[B] Antioxidant>

B-1: IRGANOX 1010FF (phenolic antioxidant)

B-2: Adhesive LA-72 (amine antioxidant)

B-3: TINUVIN 622LD (amine antioxidant)

B-4: IRGAFOS 12 (phosphorus antioxidant)

B-5: IRGANOX PS 800FL (sulfur antioxidant)

B-6: Adhesive AO-40 (phenolic antioxidant)

&Lt; Compound [C] &gt;

C-1: N, N, N ', N'-tetraglycidyl-m-xylylenediamine

C-2: EX-142 manufactured by Nagase Chemical Industries, Ltd.

C-3: N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane

C-5: Aron oxetane OXT-121

C-6: dipentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether

[Example 1]

NMP and ethylene glycol-mono-n-butyl ether were added to a solution containing 100 parts by mass of the polyimide (A-1) as the polymer [A], and 3 parts by mass of the above (B- And 2 mass parts of the above (C-1) as the [C] compound were added and sufficiently stirred to obtain a solution having a solvent composition of NMP: ethylene glycol-mono-n-butyl ether = 60: 40 (mass ratio) did. This solution was filtered using a filter having a pore diameter of 1 탆 to prepare a liquid crystal aligning agent.

[Examples 2 to 39 and Comparative Examples 1 to 12]

Each of the liquid crystal aligning agents was prepared in the same manner as in Example 1, except that the kinds and contents of the components to be blended were changed to the types and contents described in Table 1, respectively. In Table 1, "-" indicates that the corresponding component was not used.

&Lt; Formation of liquid crystal alignment film &

Each liquid crystal aligning agent was applied to the transparent electrode surface of a glass substrate with a transparent electrode made of ITO film having a thickness of 1 mm by a spinner and prebaked at 80 DEG C for 1 minute on a hot plate and then baked at 210 DEG C for 30 minutes Thereby forming a liquid crystal alignment film having a film thickness of about 80 nm.

&Lt; Production of liquid crystal display element &

The formation of the liquid crystal alignment film was repeated to obtain a pair of substrates (two pieces) having a liquid crystal alignment film. Next, an epoxy resin adhesive containing an aluminum oxide spheres having a diameter of 5.5 占 퐉 was applied to the outer edge of any one of the pair of substrates having the liquid crystal alignment film, and the adhesive was superimposed on the liquid crystal alignment film so as to face each other, The adhesive was cured. Subsequently, a nematic liquid crystal (MLC-6608, 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 produce a liquid crystal cell. This was repeated to produce another pair of liquid crystal cells.

<evaluation>

The following liquid crystal alignment films and liquid crystal display devices were evaluated as described below. The results are also shown in Table 1.

[Light Resistance]

A voltage of 5 V was applied to the pair of liquid crystal cells at 70 캜 for an application time of 60 microseconds and a span of 167 milliseconds and then a voltage maintenance rate of 167 milliseconds after the application was released was measured using a VHR- 1. This value was set as an initial voltage maintenance ratio (VH ₁ ) (%). Then, the liquid crystal cell after the measurement of the initial voltage maintenance rate was irradiated with light for 1,000 hours using a weather meter having a carbon arc as a light source. For the liquid crystal cell after light irradiation, the voltage holding ratio was again measured by the same method as described above. This value was defined as the voltage maintenance rate (VH ₂ ) (%) after light irradiation. The reduction amount? VHR (%) of the voltage holding ratio was determined by the following formula, and the light resistance was determined.

? VHR (%) = VH ₁ -VH ₂

When the? VHR was less than 2.5%, the light resistance was excellent, the case where the VHR was 2.5% or more and less than 5.0% was good, and the case where the VHR was 5.0% or more was judged as poor.

However,

A voltage of 5 V was applied to the other pair of liquid crystal cells prepared above at 70 캜 for an application time of 60 microseconds and a span of 167 milliseconds and then the voltage maintenance ratio after 167 milliseconds after the application was released was measured using a voltage- Of VHR-1. This value was set as an initial voltage holding ratio (VH ₃ ) (%). Subsequently, the liquid crystal cell after storing the liquid crystal cell after the measurement of the initial voltage maintenance rate in an oven set at 60 DEG C and a humidity of 90% for 500 hours was measured again for the voltage preservation rate by the same method as described above. This value was defined as the voltage conservation rate (VH ₄ ) (%) after high temperature and high humidity stress. The reduction amount? VHR '(%) of the voltage holding ratio was determined by the following formula, and the resultant was made to be hot and humid.

? VHR '(%) = VH ₃ -VH ₄

In the case where? VHR 'was less than 3.0%, it was judged that the exothermic and high humidity was excellent, the case of 3.0% or more and less than 5.0% was good, and the case of 5.0% or more was judged to be defective.

[Re-workability]

The liquid crystal aligning agent prepared above was applied to a transparent conductive film made of ITO formed on one side of a glass substrate having a thickness of 1 mm by a spinner and prebaked at 100 캜 for 90 seconds on a hot plate to form a film having a thickness of about 80 nm Was formed. This operation was repeated to prepare two substrates having a coating film. Next, the obtained two substrates were stored in a dark room at 25 캜 in a nitrogen atmosphere. After 12 hours and 72 hours from the start of storage, each sample was taken out from the dark room and immersed in a beaker containing NMP at 40 DEG C for 2 minutes. After 2 minutes, the substrate was removed from the beaker, washed several times with ultrapure water, and then water droplets were removed from the surface with an air blow, and the substrate was observed to observe the coating film remaining by an optical microscope. (A), the remnant of the coating film was observed on the substrate after 72 hours, but the remnant of the coating film was not observed as the substrate removed from the dark room after 12 hours (B). In the case where the residue of the coating film was observed as a substrate taken out from the dark room after 12 hours, it was judged to be defective (C).

As apparent from the results of Table 1, the liquid crystal aligning agent of the present invention maintains good electrical characteristics even when continuous driving is performed for a long time under a severe environment of optical stress, heat and humidity, It is possible to form a liquid crystal alignment film having excellent properties.

According to the liquid crystal aligning agent of the present invention, it is possible to provide a liquid crystal alignment film excellent in electrical properties even when continuous driving is performed for a long time under severe environments such as optical stress, heat and humidity, . Therefore, the liquid crystal display element of the present invention including the liquid crystal alignment film is less deteriorated in display quality and can be effectively applied to various apparatuses. For example, the liquid crystal display element includes a clock, a portable game, a word processor, System, a camcorder, a portable information terminal, a digital camera, a mobile phone, various monitors, a liquid crystal television, and the like.

Claims (7)

[A] at least one polymer selected from the group consisting of polyamic acid and polyimide obtained by dehydrocondensing the polyamic acid,
[B] an antioxidant, and
[C] a compound containing an epoxy group,
Wherein the polymer [A] is selected from the group consisting of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- 3-dione, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5 -Dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione and 2,4,6,8-tetracarboxybicyclo [3.3.0] octane- Is a polymer obtained by reacting a tetracarboxylic acid dianhydride containing at least one member selected from the group consisting of 6,8-dianhydride and diamine,
Wherein the [B] antioxidant is at least one selected from the group consisting of a phenol antioxidant, an amine antioxidant (except for the piperidine antioxidant), a phosphorus antioxidant, a sulfur antioxidant, Orientation agent. The method according to claim 1,
[B] Liquid crystal aligning agent having a group represented by the following formula (2) as the antioxidant:

(In the formula (2), R ⁶ is a hydrocarbon group having 4 to 16 carbon atoms, provided that the hydrocarbon group may have an oxygen atom or a sulfur atom in the carbon skeleton chain; a is an integer of 0 to 3; R ⁷ is a hydrogen atom or a hydrocarbon group having 1 to 16 carbon atoms, provided that when there are plural R ^{7 s} , plural R ^{7 s} may be the same or different). 3. The method according to claim 1 or 2,
The liquid crystal aligning agent wherein the [C] compound is an epoxy group-containing polyorganosiloxane or a monofunctional epoxy compound. delete The method according to claim 1,
Wherein the diamine is selected from the group consisting of 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden- -1,3,3-trimethyl-1H-inden-6-amine, and a liquid crystal aligning agent comprising at least one member selected from the group consisting of: A liquid crystal alignment film formed by the liquid crystal aligning agent according to claim 1 or 2. A liquid crystal display element comprising the liquid crystal alignment film according to claim 6.