TWI541271B - Liquid crystal orientation agent, liquid crystal orientation film and liquid crystal display device - Google Patents

Description

Liquid crystal alignment agent, method for forming liquid crystal alignment film, and liquid crystal display element

The present invention relates to a liquid crystal alignment agent, a method of forming a liquid crystal alignment film, and a liquid crystal display element. More specifically, it relates to a liquid crystal alignment agent and a liquid crystal display element having excellent display quality, and the liquid crystal alignment agent can provide a liquid crystal alignment film excellent in alignment control power of liquid crystal molecules.

In the liquid crystal display device, a liquid crystal alignment film is provided on the surface of the substrate in order to align liquid crystal molecules in a certain direction with respect to the surface of the substrate. The liquid crystal alignment film is generally formed by a method (rubbing method) of rubbing the surface of the organic film formed on the surface of the substrate in the same direction with a cloth such as rayon. However, the formation of the liquid crystal alignment film is performed by the rubbing treatment, dust and static electricity are easily generated in the rubbing step, and dust is attached to the surface of the alignment film to cause display failure, and TFT (thin film transistor) element is provided. In the case of the substrate, the circuit of the TFT element is broken due to the generated static electricity, which causes a decrease in the yield of the product. Therefore, in the liquid crystal cell, as a means for aligning the liquid crystal, it is also proposed to irradiate the polarized or non-polarized radiation to the radiation-sensitive organic thin film formed on the surface of the substrate to impart a liquid alignment method to the liquid crystal alignment energy (see Patent Document 1 to 6). According to this photo-alignment method, dust and static electricity are not generated in the step, and uniform liquid crystal alignment can be formed.

The liquid crystal display element is a liquid crystal display element using a horizontal alignment mode of a nematic liquid crystal having a positive dielectric anisotropy, such as a TN (twisted nematic) type or an STN (super twisted nematic) type, and the like. A VA (Vertical Alignment) type liquid crystal display element using a vertical (vertical molecular arrangement) alignment mode of nematic liquid crystal having negative dielectric anisotropy is known. In the vertical alignment mode, when a voltage is applied between the substrates and the liquid crystal molecules are inclined in a direction parallel to the substrate, the liquid crystal molecules must be inclined from the substrate normal direction with respect to a certain direction. The above-described photoalignment method also functions as a method of controlling the tilt direction of liquid crystal molecules in the liquid crystal display element of the vertical alignment mode (Patent Documents 1, 2, and 4 to 6).

Thus, the liquid crystal alignment film produced by the photoalignment method is a liquid crystal alignment film which is suitable for various liquid crystal display elements.

However, when a liquid crystal alignment film suitable for a TN type, STN type or vertical alignment type liquid crystal display element is formed by a photo-alignment method, a liquid crystal alignment agent capable of stably exhibiting a liquid crystal alignment control force suitable for an industrial level has not been known. In particular, when it is used for a liquid crystal display element of a vertical alignment type, a polymer constituting a liquid crystal alignment film which exhibits a liquid crystal alignment control force in a direction perpendicular to a substrate surface has to have a straight liquid crystal structure, and therefore contains The coating property or the printability of the liquid crystal alignment agent of the polymer is impaired, and a vertical alignment type liquid crystal alignment agent for a photo-alignment method having good liquid crystal alignment property and good coating property has not been known until now.

In recent years, a liquid crystal display element of a lateral electric field method (IPS method) has been proposed (see Patent Document 7). The liquid crystal display device of the horizontal electrolysis type is an electrode in which an electrode is formed only on one side of a pair of substrates disposed opposite to each other, and an electric field type is generated in a direction parallel to the substrate, and an electrode is formed on both substrates. In the conventional vertical electric field type liquid crystal display element which generates an electric field in the direction perpendicular to the substrate, it is known that it has a wide viewing angle characteristic and can perform high-quality display. In the liquid crystal display device of the horizontal electric field type, since the liquid crystal molecules respond to the electric field only in the direction parallel to the substrate, the refractive index change in the long-axis direction of the liquid crystal molecules does not occur, and the observer visually confirms even when the viewing angle is changed. The contrast ratio and the change in the color of the display color are also small, so that high-quality display can be performed regardless of the angle of view.

However, the liquid crystal alignment film in the liquid crystal display device of the horizontal electric field type is generally formed by a rubbing method, and thus there is a problem as described above, and application of the photoalignment method is being studied. However, when a liquid crystal alignment film suitable for such a horizontal electric field type liquid crystal display element is formed by a photo-alignment method, it has been pointed out that the alignment control force of liquid crystal molecules is insufficient, and therefore improvement is required.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-307736

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2004-163646

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2002-250924

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2004-83810

[Patent Document 5] Japanese Patent Laid-Open Publication No. Hei 9-211468

[Patent Document 6] Japanese Patent Laid-Open Publication No. 2003-114437

[Patent Document 7] US Patent No. 5,958,333

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2010-97188

[Patent Document 9] JP-A-63-291922

[Non-patent literature]

[Non-Patent Document 1] "Science of Sol-Gel Method", issued by agne Chengfeng (share), 1988, pp. 154-161

The present invention has been made in view of the above circumstances, and an object thereof is to provide an alignment control force capable of imparting alignment control to a liquid crystal molecule by a photo-alignment method, and a vertical alignment control force and a coating property when used for a vertical alignment type liquid crystal display element. On the other hand, when it is used for a liquid crystal display element of a TN type, an STN type, or a lateral electrolysis type, the liquid crystal alignment agent of the liquid crystal alignment film which is excellent in the alignment control force is also used.

Another object of the present invention is to provide a liquid crystal display element which is excellent in liquid crystal alignment control force and excellent in display quality.

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

The above objects and advantages of the present invention are attained by a liquid crystal alignment agent containing a radiation sensitive polymer having a structure represented by the following formula (A');

Second, it is achieved by a liquid crystal display element having a liquid crystal alignment film formed of the above liquid crystal alignment agent.

The liquid crystal alignment agent of the present invention can form an alignment control force imparted to the liquid crystal molecules by the photoalignment method, and balance the vertical alignment control force and coating property of the liquid crystal molecules when used for a vertical alignment type liquid crystal display element. On the other hand, when it is used for a liquid crystal display element of a TN type, an STN type, or a horizontal electric field type, it is a liquid crystal alignment film which is excellent in the alignment control of liquid crystal molecules.

The liquid crystal display element of the present invention having such a liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention can be used for various display devices because it can perform high-quality display and is inexpensive.

Further, the coating film formed of the liquid crystal alignment agent of the present invention can be applied to an insulating film in an electronic material.

[Formation for implementing the invention]

The liquid crystal alignment agent of the present invention contains a radiation sensitive polymer having a structure represented by the above formula (A'). In the above formula (A'), the benzylic carbon adjacent to the benzene ring on the right side preferably has at least one hydrogen atom.

Examples of the skeleton of the above-mentioned radiation-sensitive polymer include polylysine, polyimine, polyphthalate, polyorganosiloxane, polyester, polyamine, cellulose and derivatives thereof, and polycondensation. Acetal, polystyrene and derivatives thereof, poly(styrene-phenylmaleimide) and derivatives thereof, poly(meth)acrylates and the like, among which polyorganosiloxanes are preferred. In other words, the radiation sensitive polymer contained in the liquid crystal alignment agent of the present invention is preferably a radiation sensitive polyorganosiloxane having a structure represented by the above formula (A').

<Inductive radioactive polyorganosiloxane>

The liquid crystal alignment agent of the present invention preferably contains a radiation-sensitive polyorganosiloxane having a structure represented by the above formula (A').

The content of the structure represented by the above formula (A') in the radiation-sensitive polyorganosiloxane containing the liquid crystal alignment agent of the present invention is preferably 0.2 to 6 mmol/g polymer, and more preferably It is 0.3 to 5 millimoles per gram of polymer.

The radiation sensitive polyorganosiloxane contained in the liquid crystal alignment agent of the present invention preferably further has an epoxy group in addition to the group represented by the above formula (A'). At this time, the epoxy equivalent of the radiation-sensitive polyorganosiloxane is preferably 150 g/mol or more, more preferably 200 to 10,000 g/mol, and still more preferably 200 to 2,000 g/mole. By using such an epoxy equivalent radiation-sensitive polyorganosiloxane, the liquid crystal alignment agent of the present invention does not impair the storage stability of the liquid crystal alignment agent, and can form a liquid crystal alignment property more excellently, and excellent afterimage characteristics. The liquid crystal alignment film is therefore preferred.

The polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography of the radiation-sensitive polyorganosiloxane contained in the liquid crystal alignment agent of the present invention is preferably 1,000 to 200,000, more preferably 2,000 to 100,000. Very good is 3,000~30,000.

<Synthesis of Radiation-Specific Polyorganosiloxanes>

The liquid crystal alignment agent of the present invention preferably contains a radiation-sensitive polyorganosiloxane, and as long as it is as described above, the obtained substance can be synthesized by any method. The method for synthesizing the radiation-sensitive polyorganosiloxane which is contained in the liquid crystal alignment agent of the present invention, for example, a hydrolyzable decane compound having the structure represented by the above formula (A') or the hydrolyzable decane compound and the like a method of hydrolyzing and condensing a mixture of hydrolyzable decane compounds, a method of reacting a polyorganosiloxane having an epoxy group, and a compound represented by the following formula (A) (hereinafter referred to as "carboxylic acid (A)") ,

In the formula (A), R is independently an alkyl group having 1 to 4 carbon atoms, a halogen atom or a cyano group, n1 is an integer of 0 to 3, n2 is an integer of 0 to 4, and R ¹ is the following formula (R- 1) or a group represented by (R-2), wherein R ² and R ³ are each a group represented by the following formula (R-3), wherein one of Z present in the formula (A) is a carboxyl group, and the others are A hydrogen atom.

*-R ⁵ -Z (R-2)

*-X ² -R ⁶ -Z (R-3)

Wherein X ¹ in the formula (R-1) is a single bond, -O- ⁺ , -COO- ⁺ or -OCO- ⁺ , wherein the bond having "+" is the R ⁴ side, and R ⁴ is a single bond, a methylene group or an alkylene group having 2 to 5 carbon atoms, R is an alkyl group having 1 to 4 carbon atoms, a halogen atom or a cyano group, and n3 is an integer of 0 to 4, and the formula (R-2) R ⁵ is a methylene group or an alkylene group having 2 to 5 carbon atoms, and X ² in the formula (R-3) is a single bond, -O- ⁺ , -COO- ⁺ or -OCO- ⁺ , wherein , with a "+" side of the linkages ⁶ is R, R ⁶ is a single bond, a methylene group or alkylene group having a carbon number of 2 to 5, of formula (R-1) ~ (R -3) of "*" indicates the connection key.

Among them, the latter method is preferably used from the viewpoints of ease of synthesis of the raw material compound, ease of reaction, and the like.

Hereinafter, a preferred method for synthesizing the radiation-sensitive polyorganosiloxane containing the epoxy group in the liquid crystal alignment agent of the present invention, that is, a method of reacting a polyorganosiloxane having an epoxy group with a carboxylic acid (A) will be described.

[Polyorganosiloxane having an epoxy group]

The epoxy group in the polyorganosiloxane having an epoxy group is preferably an oxyethylene skeleton or a 1,2-epoxycycloalkane skeleton, which is directly bonded to a ruthenium atom or interrupted by an oxygen atom in the middle. The epoxy group contained in the group in which the alkyl group is bonded to the ruthenium atom (the group having an epoxy group) is present in the polyorganooxane. The group having such an epoxy group may, for example, be a group represented by the following formula (EP-1) or (EP-2).

(In the formulas (EP-1) and (EP-2), "*" indicates a connection key.)

The epoxy equivalent of the polyorganosiloxane having an epoxy group is preferably from 100 to 10,000 g/mole, and more preferably from 150 to 1,000 g/mole.

The polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography on the polyorganosiloxane having an epoxy group is preferably from 500 to 100,000, more preferably from 1,000 to 10,000, and particularly preferably from 1,000 to 5,000. .

The polyorganosiloxane having an epoxy group can be, for example, a decane compound having an epoxy group or a decane compound having an epoxy group, preferably in the presence of a suitable organic solvent, water and a catalyst. A mixture of other decane compounds is synthesized by hydrolysis and condensation.

The decane compound having an epoxy group may, for example, be 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropyltriethoxydecane or 3-glycidyloxypropane Methyldimethoxydecane, 3-glycidyloxypropylmethyldiethoxydecane, 3-glycidyloxypropyldimethylmethoxydecane, 3-glycidyloxy Propyl dimethyl ethoxy decane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxy decane, 2-(3,4-epoxycyclohexyl)ethyltriethoxy decane Wait.

Examples of the other decane compound include tetrachloromethane, tetramethoxy decane, tetraethoxy decane, tetra-n-propoxy decane, tetraisopropoxy decane, tetra-n-butoxy decane, and tetra-second butyl. Oxydecane, trichlorodecane, trimethoxydecane, triethoxydecane, tri-n-propoxydecane, triisopropoxydecane, tri-n-butoxydecane, tri-butoxydecane, fluorine tri Chlorodecane, fluorotrimethoxydecane, fluorotriethoxydecane, fluorotri-n-propoxy decane, fluorotriisopropoxy decane, fluorotri-n-butoxy decane, fluorotri-t-butoxy decane, A Trichlorodecane, methyltrimethoxydecane, methyltriethoxydecane, methyltri-n-propoxydecane, methyltriisopropoxydecane, methyltri-n-butoxydecane, methyltri Second butoxydecane, 2-(trifluoromethyl)ethyltrichlorodecane, 2-(trifluoromethyl)ethyltrimethoxydecane, 2-(trifluoromethyl)ethyltriethoxy Decane, 2-(trifluoromethyl)ethyltri-n-propoxydecane, 2-(trifluoromethyl)ethyltriisopropoxydecane, 2-(trifluoromethyl)ethyltri-n-butoxy Base decane 2-(Trifluoromethyl)ethyltri-t-butoxydecane, 2-(perfluoro-n-hexyl)ethyltrichlorodecane, 2-(perfluoro-n-hexyl)ethyltrimethoxydecane, 2-( Perfluoro-n-hexyl)ethyltriethoxydecane, 2-(perfluoro-n-hexyl)ethyltri-n-propoxydecane, 2-(perfluoro-n-hexyl)ethyltriisopropoxydecane, 2-( Perfluoro-n-hexyl)ethyltri-n-butoxydecane, 2-(perfluoro-n-hexyl)ethyltri-t-butoxydecane, 2-(perfluoro-n-octyl)ethyltrichlorodecane, 2-( Perfluoro-n-octyl)ethyltrimethoxydecane, 2-(perfluoro-n-octyl)ethyltriethoxydecane, 2-(perfluoro-n-octyl)ethyltri-n-propoxydecane, 2- (perfluoro-n-octyl)ethyltriisopropoxydecane, 2-(perfluoro-n-octyl)ethyltri-n-butoxydecane, 2-(perfluoro-n-octyl)ethyltri-n-butoxy Baseline, hydroxymethyltrichlorodecane, hydroxymethyltrimethoxydecane, hydroxyethyltrimethoxydecane, hydroxymethyltri-n-propoxydecane, hydroxymethyltriisopropoxydecane, hydroxymethyl three n-Butoxydecane, hydroxymethyl tri-second butoxy decane, 3-(meth) propylene methoxy propyl trichloro decane, 3 -(Meth)acryloxypropyltrimethoxydecane, 3-(meth)acryloxypropyltriethoxydecane, 3-(methyl)propenyloxypropyltri-n-propoxy Baseline, 3-(meth)acryloxypropyltriisopropoxydecane, 3-(meth)acryloxypropyltri-n-butoxyoxane, 3-(methyl)propeneoxime Propyl tri-tert-butoxy decane, 3-mercaptopropyl trichlorodecane, 3-mercaptopropyltrimethoxydecane, 3-mercaptopropyltriethoxydecane, 3-mercaptopropyltri-n-propoxy Baseline, 3-mercaptopropyltriisopropoxydecane, 3-mercaptopropyltri-n-butoxyoxydecane, 3-mercaptopropyltri-tert-butoxybutane, decylmethyltrimethoxydecane, fluorenyl Triethoxy decane, vinyl trichloro decane, vinyl trimethoxy decane, vinyl triethoxy decane, vinyl tri-n-propoxy decane, vinyl triisopropoxy decane, vinyl tri-n-butyl Butoxy decane, vinyl tri-tert-butoxy decane, allyl trichloro decane, allyl trimethoxy decane, allyl triethoxy decane, allyl tri-n-propoxy decane, olefin Propyl triisopropyl Oxy decane, allyl tri-n-butoxy decane, allyl tri-tert-butoxy decane, phenyl trichloro decane, phenyl trimethoxy decane, phenyl triethoxy decane, phenyl tri-n-butyl Propoxy decane, phenyl triisopropoxy decane, phenyl tri-n-butoxy decane, phenyl tri-n-butoxy decane, methyl dichloro decane, methyl dimethoxy decane, methyl two Ethoxy decane, methyl di-n-propoxy decane, methyl diisopropoxy decane, methyl di-n-butoxy decane, methyl di-butoxy decane, dimethyl dichloro decane, two Methyl dimethoxy decane, dimethyl diethoxy decane, dimethyl di-n-propoxy decane, dimethyl diisopropoxy decane, dimethyl di-n-butoxy decane, dimethyl Dibutylbutane, (methyl)[2-(perfluoro-n-octyl)ethyl]dichlorodecane, (methyl)[2-(perfluoro-n-octyl)ethyl]dimethoxy Decane, (methyl)[2-(perfluoro-n-octyl)ethyl]diethoxydecane, (methyl)[2-(perfluoro-n-octyl)ethyl]di-n-propoxydecane, ( Methyl)[2-(perfluoro-n-octyl)ethyl]diisopropoxydecane, (methyl)[2-(perfluoro-positive Octyl)ethyl]di-n-butoxydecane, (methyl)[2-(perfluoro-n-octyl)ethyl]di-butoxypropane, (methyl)(3-mercaptopropyl)di Chlorodecane, (methyl)(3-mercaptopropyl)dimethoxydecane, (methyl)(3-mercaptopropyl)diethoxydecane, (methyl)(3-mercaptopropyl)di-n-butyl Propoxy decane, (methyl) (3-mercaptopropyl) diisopropoxy decane, (methyl) (3-mercaptopropyl) di-n-butoxy decane, (methyl) (3-mercaptopropyl propyl) Bis), second butoxy decane, (meth) (vinyl) dichloro decane, (methyl) (vinyl) dimethoxy decane, (methyl) (vinyl) diethoxy decane, (methyl)(vinyl)di-n-propoxydecane, (methyl)(vinyl)diisopropoxydecane, (methyl)(vinyl)di-n-butoxydecane, (methyl) ( Vinyl)di-butoxybutane, divinyldichlorodecane,divinyldimethoxydecane,divinyldiethoxydecane,divinyldi-n-propoxydecane,divinyldiene Isopropoxydecane, divinyldi-n-butoxydecane, divinyldi-n-butoxydecane, diphenyldichlorodecane, diphenyldimethoxy Alkane, diphenyldiethoxydecane, diphenyldi-n-propoxydecane, diphenyldiisopropoxydecane, diphenyldi-n-butoxydecane, diphenyldi-butoxy Decane, chlorodimethyl decane, methoxy dimethyl decane, ethoxy dimethyl decane, trimethyl chloro decane, trimethyl bromo decane, trimethyl iodonane, methoxy trimethyl decane, Ethoxy trimethyl decane, n-propoxy trimethyl decane, isopropoxy trimethyl decane, n-butoxy trimethyl decane, second butoxy trimethyl decane, third butoxy Trimethyl decane, (chloro) (vinyl) dimethyl decane, (methoxy) (vinyl) dimethyl decane, (ethoxy) (vinyl) dimethyl decane, (chloro) (A) a decane compound having one ruthenium atom such as diphenyl decane, (methoxy) (methyl) diphenyl decane or (ethoxy) (methyl) diphenyl decane, in addition to List the trade names, such as KC-89, KC-89S, X-21-3153, X-21-5841, X-21-5842, X-21-5843, X-21-5844, X-21-5845, X -21-5846, X-21-5847, X-21-5848, X-22-160AS, X-22-170B, X-22-170BX, X-22-170 D, X-22-170DX, X-22-176B, X-22-176D, X-22-176DX, X-22-176F, X-40-2308, X-40-2651, X-40-2655A, X-40-2671, X-40-2672, X-40-9220, X-40-9225, X-40-9227, X-40-9246, X-40-9247, X-40-9250, X- 40-9323, X-41-1053, X-41-1056, X-41-1805, X-41-1810, KF6001, KF6002, KF6003, KR212, KR-213, KR-217, KR220L, KR242A, KR271, KR282, KR300, KR311, KR401N, KR500, KR510, KR5206, KR5230, KR5235, KR9218, KR9706 (above, Shin-Etsu Chemical Co., Ltd.); Glass Resin (Showa Electric Co., Ltd.); SH804, SH805, SH806A, SH840, SR2400, SR2402, SR2405, SR2406, SR2410, SR2411, SR2416, SR2420 (above, Toray Dow Corning Co., Ltd.); FZ3711, FZ3722 (above, Japanese unicar); DMS-S12, DMS -S15, DMS-S21, DMS-S27, DMS-S31, DMS-S32, DMS-S33, DMS-S35, DMS-S38, DMS-S42, DMS-S45, DMS-S51, DMS-227, PSD-0332 , PDS-1615, PDS-9931, XMS-5025 (above, CHISSO (manufactured by the company)); methyl decanoate MS51, methyl decanoate MS56 (above, Mitsubishi Chemical Co., Ltd.); ethyl citrate 28, Ethyl citrate 40, Ethyl citrate 48 (above, COLCOAT); a partial condensate such as GR100, GR650, GR908, GR950 (above, Showa Denko), and one or more of them can be used.

As the other decane compound, among them, tetramethoxy decane, tetraethoxy decane, methyl trimethoxy decane, methyl triethoxy decane, 3-(meth) acryloxy group are preferably used. Propyltrimethoxydecane, 3-(meth)acryloxypropyltriethoxydecane, vinyltrimethoxydecane, vinyltriethoxydecane,allyltrimethoxydecane,allyl Triethoxy decane, phenyl trimethoxy decane, phenyl triethoxy decane, 3-mercaptopropyl trimethoxy decane, 3-mercaptopropyl triethoxy decane, decyl methyl trimethoxy decane One or more selected from the group consisting of mercaptomethyltriethoxydecane, dimethyldimethoxydecane, and dimethyldiethoxydecane.

In the synthesis of the polyorganosiloxane having an epoxy group in the present invention, the use ratio of the decane compound having an epoxy group and other decane compounds is preferably adjusted so that the epoxy equivalent of the obtained polyorganosiloxane is The above preferred range.

Examples of the organic solvent that can be used in the synthesis of the polyorganosiloxane having an epoxy group include a hydrocarbon, a ketone, an ester, an ether, an alcohol, and the like.

Examples of the above-mentioned hydrocarbons include, for example, toluene and xylene; and examples of the ketone include methyl ethyl ketone, methyl isobutyl ketone, methyl n-pentanone, diethyl ketone, and cyclohexanone; and examples of the ester include, for example, the ester. Ethyl acetate, n-butyl acetate, isoamyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, ethyl lactate, etc.; as the ether, for example, ethylene glycol dimethyl ether, Ethylene glycol diethyl ether, tetrahydrofuran, two An alkane or the like; examples of the alcohol include 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, and ethylene glycol single N-butyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether and the like. Among them, a substance which is not water-soluble is preferred.

These organic solvents can be used singly or in combination of two or more.

The amount of the organic solvent to be used is preferably from 10 to 10,000 parts by weight based on the total of 100 parts by weight of the decane compound (the total of the decane compound having an epoxy group and the other decane compound used arbitrarily, the following). More preferably, it is 50 to 1,000 parts by weight.

The amount of water used in the synthesis of the polyorganosiloxane having an epoxy group is preferably 1 to 30 moles, more preferably 1 to 30 moles, per mole of the total amount of the decane compound.

Examples of the catalyst include an acid, an alkali metal compound, an organic base, a titanium compound, and a zirconium compound.

Examples of the alkali metal compound include sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, and potassium ethoxide.

The organic base may, for example, be ethylamine, diethylamine or piperazine. , organic primary or secondary amines such as piperidine, pyrrolidine, pyrrole; triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, 4-dimethylaminopyridine, diazabicycloundecene, etc. Organic tertiary amine; organic quaternary amine such as tetramethylammonium hydroxide. Among these organic bases, organic tertiary amines such as triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, and 4-dimethylaminopyridine; and organic quaternary amines such as tetramethylammonium hydroxide are preferred.

As a catalyst for synthesizing a polyorganosiloxane having an epoxy group, an alkali metal compound or an organic base is preferred. By using an alkali metal compound or an organic base as a catalyst, side reactions such as ring opening of an epoxy group are not generated, and a target polyorganosiloxane can be obtained at a high hydrolysis and condensation rate, so that production stability is excellent. Good. Further, the liquid crystal alignment agent of the present invention containing a reaction product of an epoxy group-containing polyorganosiloxane and an carboxylic acid (A) synthesized using an alkali metal compound or an organic base as a catalyst is extremely advantageous because of excellent storage stability. . The reason is presumed to be as follows in the hydrolysis and condensation reaction as indicated in Non-Patent Document 1 (Science of Sol-Gel Method, agne Chengfeng (share), 1988, pp 154-161). When an alkali metal compound or an organic base is used as the catalyst, only a part of the alkoxy decane is hydrolyzed intensively to form a polyfunctional chemical species. Therefore, the polycondensation proceeds three-dimensionally, and the polymer becomes a crosslinkable bond, so that decane can be obtained. A polyorganosiloxane having a small proportion of an alcohol group. In other words, it is presumed that the content of the sterol group of the radiation-sensitive polyorganosiloxane contained in the liquid crystal alignment agent of the present invention is small, the condensation reaction between the stanol groups is suppressed, and the liquid crystal alignment agent of the present invention contains In the case of other polymers described later, the condensation reaction between the stanol group and the other polymer is also suppressed, and thus the storage stability is excellent.

As the catalyst, an organic base is particularly preferred. The amount of the organic base to be used varies depending on the reaction conditions such as the type of the organic base and the temperature, and should be appropriately set, for example, 1 mol, preferably 0.01 to 3 mol, and more preferably the total of the decane compound. It is 0.05~1 mole.

The hydrolysis and condensation reaction in the synthesis of a polyorganosiloxane having an epoxy group is preferably carried out by dissolving a decane compound having an epoxy group and other decane compounds as needed in an organic solvent, and the solution and the organic base. The water is mixed and heated by a suitable heating device such as an oil bath.

In the hydrolysis and condensation reaction, it is desirable to make the heating temperature preferably 130 ° C or lower, more preferably 40 ° C to 100 ° C, and preferably 0.5 to 12 hours, more preferably 1 to 8 hours. While heating, the mixture may be stirred or may not be stirred, or the mixture may be placed under reflux.

After completion of the reaction, it is preferred to wash the organic solvent layer separated from the reaction mixture with water. In the case of this washing, washing with water containing a small amount of salt, for example, an aqueous solution of ammonium nitrate of about 0.2% by weight or the like is preferred, and it is preferable to facilitate the washing operation. The aqueous layer after washing to neutrality is neutral, and then the organic solvent layer is dried by using an appropriate desiccant such as anhydrous calcium sulfate or molecular sieve, and then the solvent is removed, whereby the desired polyorganosiloxane having an epoxy group can be obtained. alkyl.

In the present invention, a commercially available product can be used as the polyorganosiloxane having an epoxy group. Examples of such commercially available products include DMS-E01, DMS-E12, DMS-E21, and EMS-32 (the above are manufactured by CHISSO Co., Ltd.).

[carboxylic acid (A)]

The carboxylic acid (A) in the present invention is a compound represented by the above formula (A).

R in the above formulae (A) and (R-1) is preferably a methyl group, a fluorine atom or a cyano group; n1 and n2 in the above formula (A) and n3 in the above formula (R-1), respectively is preferably 0 or 1, more preferably 0; (R-1) in the above formulas X ¹ and (R-3) in the formula X ² are each preferably a single bond. Further, particularly preferred are compounds wherein X ¹ and R ⁴ in the above formula (R-1) and X ² and R ⁶ in the above formula (R-3) are each a single bond.

Specific examples of the carboxylic acid (A) include the following formulas (A-1) to (A-15).

(In the above formula, n and m are each an integer of 1 to 5.)

One or more selected from these carboxylic acids can be used. Among them, preferred are compounds represented by (A-1), (A-2) and (A-5) to (A-8), and more preferably (A-1) and (A-2) respectively. The compound represented.

The carboxylic acid (A) can be synthesized by a suitable combination of conventional methods of organic chemistry.

For example, the compound represented by the above formula (A-1) or (A-2) forms a sodium salt by reacting 2-hydroxybenzophenone with sodium hydride, and further with an alkyl group of 3-(halomethyl)benzoate. After the alkyl group of 4-(halomethyl)benzoate is reacted, the ester bond is hydrolyzed to obtain each.

[Synthesis of Radiation-Specific Polyorganosiloxanes]

The liquid crystal alignment agent of the present invention preferably contains a radiation-sensitive polyorganosiloxane, which can be obtained by using a polyorganosiloxane having an epoxy group as described above and a carboxylic acid (A). It is preferably obtained by reacting in the presence of a catalyst and an organic solvent.

Here, the total of the carboxylic acid (A) is preferably 0.01 to 5 moles, more preferably 0.05 to 2 moles, and still more preferably the epoxy group 1 mole of the polyorganosiloxane. Use 0.1 to 0.8 moles.

In the present invention, a compound represented by the following formula (B) is used together with the carboxylic acid (A) within the range not impairing the effects of the present invention.

R ^I -R ^II -COOH (B)

(In the formula (B), R ^I is an alkyl group or alkoxy group having 8 to 20 carbon atoms or a fluoroalkyl group or a fluoroalkoxy group having 4 to 21 carbon atoms, and R ^II is a single bond, 1,4-cyclohexylene or 1,4-phenylene).

In this case, the synthesis of the radiation-sensitive polyorganosiloxane can be carried out by reacting a polyorganosiloxane having an epoxy group with a mixture of the carboxylic acid (A) and the compound represented by the above formula (B).

Preferred examples of the compound represented by the above formula (B) include compounds represented by the following formulas (B-1) to (B to 4).

(In the above formula, f is an integer from 1 to 3, g is an integer from 3 to 18, h is an integer from 5 to 20, i is an integer from 1 to 3, j is an integer from 0 to 18, and k is from 1 to 18. The integer.)

Among them, the compounds represented by the following formulas (B-3-1) to (B-3-3) are preferably used, and one or more of them may be used.

Since the compound represented by the above formula (B) is a compound in which a carboxylic acid (A) is reacted with a polyorganosiloxane having an epoxy group to form a site which imparts a pretilt angle expression to the obtained liquid crystal alignment film, It is preferably used when the liquid crystal alignment agent of the present invention is used for a vertical alignment type liquid crystal display element. In the present specification, the compound represented by the above formula (B) is hereinafter referred to as "other carboxylic acid".

In the present invention, when the carboxylic acid (A) is used together with other carboxylic acids, the total use ratio of the carboxylic acid (A) and the other carboxylic acid is 1 molar relative to the epoxy group of the polyorganosiloxane. Preferably, it is 0.001 to 1.5 moles, more preferably 0.01 to 1 mole, and still more preferably 0.05 to 0.9 moles. In this case, the total amount of the other carboxylic acid relative to the carboxylic acid (A) is preferably 50 mol% or less, more preferably 25 mol% or less. When the use ratio of the other carboxylic acid exceeds 50 mol%, when the liquid crystal display element is turned on, there is a case where an abnormal region defect occurs.

As the catalyst, an organic base or a compound known as a so-called curing accelerator which promotes the reaction between an epoxy compound and an acid anhydride can be used.

The organic base may, for example, be ethylamine, diethylamine or piperazine. , organic primary or secondary amines such as piperidine, pyrrolidine, pyrrole; triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, 4-dimethylaminopyridine, diazabicycloundecene, etc. Organic tertiary amine; organic quaternary amine such as tetramethylammonium hydroxide.

Among these organic bases, organic tertiary amines such as triethylamine, tri-n-propylamine, tri-n-butylamine, pyridine, and 4-dimethylaminopyridine; and organic quaternary amines such as tetramethylammonium hydroxide are preferred.

Examples of the curing accelerator include tertiary amines such as benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, cyclohexyldimethylamine, and triethanolamine; Imidazole, 2-n-heptyl imidazole, 2-n-undecylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl 2-phenylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1-(2-cyanoethyl)-2-methylimidazole, 1-(2- Cyanoethyl)-2-n-undecylimidazole, 1-(2-cyanoethyl)-2-phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4- Methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4,5-di(hydroxymethyl)imidazole, 1-(2-cyanoethyl)-2 -Phenyl-4,5-bis[(2'-cyanoethoxy)methyl]imidazole, 1-(2-cyanoethyl)-2-n-undecylimidazolium trimellitate , 1-(2-cyanoethyl)-2-phenylimidazolium trimellitate, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazolium trimellitic acid Salt, 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-s-three 2,4-Diamino-6-(2'-n-undecylimidazolyl)ethyl-s-three 2,4-Diamino-6-[2'-ethyl-4'-methylimidazolyl-(1' azole)ethyl-s-three , isocyanuric acid addition product of 2-methylimidazole, isocyanuric acid addition product of 2-phenylimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1 ')] Ethyl-s-three Imidazole compound such as isocyanuric acid adduct; organic phosphorus compound such as diphenylphosphine, triphenylphosphine, triphenyl phosphite; benzyltriphenylphosphonium chloride, tetra-n-butylphosphonium bromide, Triphenylphosphonium bromide, ethyltriphenylphosphonium bromide, n-butyltriphenylphosphonium bromide, tetraphenylphosphonium bromide, ethyltriphenylphosphonium iodide, ethyltriphenylphosphonium acetate Salt, tetra-n-butyl fluorene, o,o-diethyldithiophosphate, tetra-n-butyl benzotriazole salt, tetra-n-butyl fluorene tetrafluoroborate, tetra-n-butyl fluorene tetraphenyl a quaternary phosphonium salt such as borate or tetraphenylphosphonium tetraphenylborate; a diazabicycloalkenyl such as 1,8-diazabicyclo[5.4.0]undecene-7 or an organic acid salt thereof; Organometallic compounds such as zinc octoate, tin octoate, acetonitrile aluminum complex; tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride, tetra-n-butylammonium chloride, etc. Ammonium salt; boron compound such as boron trifluoride or triphenyl borate; metal halide such as zinc chloride or tin chloride; amine addition accelerator such as diamine diamine or an adduct of an amine and an epoxy resin; High melting point dispersion Potential hardening accelerator: a microcapsule latent curing accelerator which coats the surface of a hardening accelerator such as an imidazole compound, an organic phosphorus compound or a quaternary phosphonium salt by a polymer: an amine salt type latent hardening accelerator: Lewis acid A latent curing accelerator such as a pyrolysis type thermal cationic polymerization latent curing accelerator such as a salt or a Buchholate.

Among them, a quaternary ammonium salt such as tetraethylammonium bromide, tetra-n-butylammonium bromide, tetraethylammonium chloride or tetra-n-butylammonium chloride is preferred.

The catalyst is preferably used in an amount of preferably 100 parts by weight or less, more preferably 0.01 to 100 parts by weight, still more preferably 0.1 to 20 parts by weight, based on 100 parts by weight of the polyorganosiloxane having an epoxy group.

The reaction of the polyorganosiloxane having an epoxy group with the carboxylic acid (A) can be carried out in the presence of an organic solvent as needed. Examples of such an organic solvent include a hydrocarbon, an ether, an ester, a ketone, a decylamine, an alcohol, and the like. Among them, ethers, esters, and ketones are preferred from the viewpoints of solubility of raw materials and products, and ease of purification of products. The solvent is preferably used in a ratio of a solid content concentration (the ratio of the weight of the component other than the solvent in the reaction solution to the total weight of the solution) of 0.1% by weight or more, more preferably 5 to 50% by weight.

The reaction temperature is preferably 0 to 200 ° C, more preferably 50 to 150 ° C. The reaction time is preferably from 0.1 to 50 hours, more preferably from 0.5 to 20 hours.

The synthesis of the radiation sensitive polyorganosiloxane described above is a method in which the ring-opening addition of the epoxy group of the polyorganosiloxane having an epoxy group is introduced into the above formula (A' ) the group indicated. This synthesis method is simple and is an extremely suitable method for improving the introduction rate of the structure represented by the above formula (A').

<Other ingredients>

The liquid crystal alignment agent of the present invention contains the radiation sensitive polymer as described above, and is preferably a radiation sensitive polyorganosiloxane.

The liquid crystal alignment agent of the present invention may further contain other components in addition to the radiation sensitive polymer as described above and preferably a radiation sensitive polyorganosiloxane, as long as the effects of the present invention are not impaired. Examples of such other components include a polymer other than the radiation sensitive polymer (hereinafter referred to as "other polymer"), a curing agent, a curing catalyst, a curing accelerator, and at least one epoxy group in the molecule. a compound (in addition to the above-mentioned radiation-sensitive polyorganosiloxane) (hereinafter referred to as "epoxy compound") or a functional decane compound (in addition to the above-mentioned radiation-sensitive polyorganosiloxane) ), surfactants, and the like.

[other polymers]

The above other polymer can be used to further improve the solution characteristics of the liquid crystal alignment agent of the present invention and the electrical characteristics of the obtained liquid crystal alignment film. Such other polymer is a polymer which does not have the structure represented by the above formula (A'), and is preferably, for example, polylysine or polyimine; a polymerization other than the above-mentioned radiation-sensitive polyorganosiloxane Organic decane (hereinafter referred to as "other polyorganosiloxane"): polyphthalate, polyester, polyamine, cellulose derivative, polyacetal, polystyrene derivative, poly(benzene) An ethylene-phenylmaleimide derivative, a poly(meth)acrylate, or the like, and one or more of them can be used.

As the other polymer in the present invention, it is preferred to use at least one polymer selected from the group consisting of polylysine, polyimine, and other polyorganosiloxanes, and more preferably from polyamine. At least one polymer or other polyorganosiloxane which is selected from the group consisting of an acid and a polyimine.

{polyglycine}

The polyamic acid can be obtained by reacting a tetracarboxylic dianhydride with a diamine compound. The tetracarboxylic dianhydride and the diamine used herein do not have the structure represented by the above formula (A').

Examples of the tetracarboxylic dianhydride used for the synthesis of the polyglycolic acid of the present invention include aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride. Specific examples of the aliphatic tetracarboxylic dianhydride include, for example, butane tetracarboxylic dianhydride; and examples of the alicyclic tetracarboxylic dianhydride include 1,2,3,4-cyclobutane. Tetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo- 3-furyl)-naphtho[1,2-c]furan-1,3-dione, 1,3,3a,4,5,9b-hexahydro-8-methyl-5-(tetrahydro- 2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, 3-oxabicyclo[3.2.1]octane-2,4-dione -6-spiro-3'-(tetrahydrofuran-2',5'-dione), 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene -1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2:3,5:6-dianhydride, 2,4,6,8-tetracarboxybicyclo[ 3.3.0] Octane-2:4,6:8-dianhydride, 4,9-dioxatricyclo[5.3.1.0 ^2,6 ]undecane-3,5,8,10-tetraketone, etc. In the case of the aromatic tetracarboxylic dianhydride, for example, pyromellitic dianhydride, and the like, and the tetracarboxylic acid II described in JP-A-2010-97188 can be used. anhydride.

As the tetracarboxylic dianhydride for synthesizing the aforementioned polyamic acid, it preferably contains an alicyclic tetracarboxylic dianhydride, and more preferably contains 2,3,5-tricarboxycyclopentyl acetic acid dianhydride. And at least one selected from the group consisting of 1,2,3,4-cyclobutanetetracarboxylic dianhydride, and particularly preferably 2,3,5-tricarboxycyclopentyl acetic acid dianhydride.

As the tetracarboxylic dianhydride for synthesizing the polyamic acid, it is preferable to contain 10 mol% or more of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride with respect to all tetracarboxylic dianhydrides. At least one selected from the group consisting of 1,2,3,4-cyclobutanetetracarboxylic dianhydride, more preferably 20 mol% or more, and most preferably only 2,3,5-tricarboxyl group At least one selected from the group consisting of cyclopentyl acetic acid dianhydride and 1,2,3,4-cyclobutane tetracarboxylic dianhydride.

Examples of the diamine used for the synthesis of the polyamic acid include an aliphatic diamine, an alicyclic diamine, an aromatic diamine, a diamine organic decane, and the like. Specific examples of the aliphatic diamine include m-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine; Examples of the alicyclic diamine include 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), and 1,3-bis(aminomethyl)cyclohexane. The aromatic diamine may, for example, be o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylmethane or 4,4'-diaminodiphenyl. Thioether, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-di(trifluoro Methyl)biphenyl, 2,7-diaminopurine, 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 9 , 9-bis(4-aminophenyl)anthracene, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl) Hexafluoropropane, 4,4'-(p-phenylenediisopropylidene)bis(aniline), 4,4'-(m-phenylenediisopropylidene)bis(aniline), 1,4-bis(4) -aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-di Aminopyrimidine, 3,6-diaminoacridine 3,6-Diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-di Amino carbazole, N,N'-bis(4-aminophenyl)benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, 1, 4-bis(4-aminophenyl)perazine , 3,5-diaminobenzoic acid, cholestyloxy-3,5-diaminobenzene, cholestyloxy-3,5-diaminobenzene, cholestyloxy-2,4 -diaminobenzene, cholesteneoxy-2,4-diaminobenzene, cholesteryl 3,5-diaminobenzoate, cholesteryl 3,5-diaminobenzoate , 3,5-diaminobenzoic acid lanthanum alkyl ester, 3,6-bis(4-aminobenzylideneoxy)cholestane, 3,6-bis(4-aminophenoxy) Cholestane, 4-(4'-trifluoromethoxybenzylideneoxy)cyclohexyl-3,5-diaminobenzoate, 4-(4'-trifluoromethylbenzonitrileoxy) Cyclohexyl-3,5-diaminobenzoate, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane, 1,1 - bis(4-((aminophenyl)methyl)phenyl)-4-heptylcyclohexane, 1,1-bis(4-((aminophenoxy)methyl)phenyl)- 4-heptylcyclohexane, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-(4-heptylcyclohexyl)cyclohexane, 1,3-di( N-(4-aminophenyl)piperidinyl)propane, N,N-hexadienediminoaniline, ω-aminoalkylaniline, and a compound represented by the following formula (D-0);

In the formula (D-0), X ¹ is a single bond, a methylene group, an alkylene group having 2 or 3 carbon atoms, *-O-, *-COO-, *-OCO-, *-X'- R-, *-R-X'- or *-X'-R-X'- (where X' is ⁺ -O-, ⁺ -COO- or ⁺ -OCO-, respectively, where "+" is the band The connection key has a left direction toward the formula (D-0), R is an alkyl group having 2 or 3 carbon atoms, and a bond with a "*" bond to the diaminophenyl group, Ring ¹ And Ring ^{2 is} independently a cyclohexylene group or a phenylene group, and X" is a single bond, ⁺ -O-, ⁺ -COO- or ⁺ -OCO-, wherein "+" is expressed as a linkage orientation with a bond (D-0) in the left direction, a is 0 or 1, b is an integer of 0 to 3, b is 2 or more, plural X "and Ring ² are the same as each other, they may be different from each other, a When 0, the leftmost X" of the formula (D-0) is a single bond, c is an integer of 0-20, and α and β are integers of 0~2C+1, respectively, where α+β=2C+1 And, when a+b=0, c is not 0.

In addition to the 1,3-di(3-aminopropyl)-tetramethyl decane, for example, Patent Document 8 (Japanese Patent Laid-Open Publication No. 2010-97188) ) the diamines described.

As in the above formula (D-0) X ^I, preferably * -O -, * - COO- or -OCO- *, wherein, with a "*" linkages bonded to the diamino phenyl.

The cyclohexylene group and the phenylene group as Ring ¹ and Ring ² are preferably a 1,4-cyclohexylene group and a 1,4-phenylene group, respectively. Ring ^{1 is} preferably a 1,4-phenylene group, and Ring ^{2 is} preferably a 1,4-cyclohexylene group.

As X", it is preferably a single bond.

α is 2c+1 and β is 0, that is, the preferred group C _c H _α F _β - is a group C _c H _2C+1 -.

a+b is an integer of 2 to 4, or a+b is 0 or 1, and c is preferably 6 or more. Among them, a+b is preferably an integer of 2 to 4.

The preferred structure of the compound represented by the above formula (D-0) is, for example, a compound represented by the following formula (D-1).

In the formula (D-1), X ^I is *-O-, *-COO- or *-OCO-, wherein a bond having a "*" is bonded to a diaminophenyl group, and a is 0 or 1 , b is an integer from 0 to 2, and c is an integer from 1 to 20.

Specific examples of the compound represented by the above formula (D-1) include, for example, dodecyloxy-2,4-diaminobenzene, tetradecyloxy-2,4-diaminobenzene, and ten Pentameryl-2,4-diaminobenzene, cetyloxy-2,4-diaminobenzene, octadecyloxy-2,4-diaminobenzene, dodecyloxy- 2,5-Diaminobenzene, tetradecyloxy-2,5-diaminobenzene, pentadecyloxy-2,5-diaminobenzene, hexadecyloxy-2,5-di Aminobenzene, octadecyloxy-2,5-diaminobenzene, a compound represented by the following formula (D-1-1) to (D-1-3), and the like.

In the above formula (D-1), it is preferred that a and b are not 0 at the same time.

These diamines may be used singly or in combination of two or more.

The ratio of use of the tetracarboxylic dianhydride and the diamine provided in the polyaminic acid synthesis reaction is preferably 1 equivalent to the amine group contained in the diamine compound, and the acid anhydride group of the tetracarboxylic dianhydride is 0.2 to 2 The ratio of the equivalents is more preferably from 0.3 to 1.2 equivalents.

The synthesis reaction of polylysine is preferably carried out in an organic solvent, preferably at a temperature of -20 to 150 ° C, more preferably 0 to 100 ° C, preferably 0.5 to 24 hours, and more preferably Good for 2~10 hours. Here, the organic solvent is not particularly limited as long as it can dissolve the synthesized polyaminic acid, and examples thereof include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and N. Aprotic polar solvents such as N-dimethylformamide, N,N-dimethylimidazolidinone, dimethyl hydrazine, γ-butyrolactone, tetramethylurea, hexamethylphosphonium triamine a phenolic solvent such as m-cresol, xylenol, phenol or halogenated phenol. The amount (a) of the organic solvent used is preferably such that the total amount (b) of the tetracarboxylic dianhydride and the diamine compound is 0.1 to 50% by weight based on the total amount (a+b) of the reaction solution, and more preferably It is an amount of 5 to 30% by weight.

As described above, a reaction solution formed by dissolving polylysine can be obtained. The reaction solution may be directly supplied to the liquid crystal alignment agent, or may be prepared by separating the polyamic acid contained in the reaction solution and then supplying the liquid crystal alignment agent, or may further purify the separated polyamic acid. Modulation of liquid crystal alignment agent.

When polypyridic acid is dehydrated and closed to form polyimine, the above reaction solution may be directly supplied to the dehydration ring-closure reaction, or the poly-proline contained in the reaction solution may be separated and supplied to the dehydration ring-closing reaction, or may be separated. The polylysine is purified and then supplied to a dehydration ring closure reaction.

The separation of the polyamic acid can be carried out by injecting the above reaction solution into a large amount of a poor solvent to obtain a precipitate, and drying the precipitate under reduced pressure or distilling off the reaction solution by using an evaporator under reduced pressure. The method of an organic solvent etc. is performed. Further, the polylysine may be redissolved in an organic solvent, followed by precipitation with a poor solvent, or polylysine may be dissolved again in an organic solvent, and the resulting solution may be washed. The poly-proline is purified by one or more steps of a step of distilling off the organic solvent in the solution using an evaporator under reduced pressure.

{polyimine}

The polyimine can be synthesized by dehydrating and ring-closing the structure of the proline which is obtained by the polyamic acid which does not have the structure represented by the above formula (A'). At this time, the entire proline structure can be dehydrated and closed to be completely imidized, or only a part of the proline structure can be dehydrated and closed to form a partial ruthenium imide of a proline structure and a quinone structure. .

The dehydration ring closure of polylysine can be carried out by (i) heating the poly-proline, or (ii) dissolving the poly-proline in an organic solvent, and adding a dehydrating agent and a dehydration ring-closing catalyst to the solution, and It is carried out according to a method of heating or the like.

The reaction temperature in the above (i) method of heating the polyamic acid is preferably 50 to 200 ° C, and more preferably 60 to 170 ° C. When the reaction temperature is less than 50 ° C, the dehydration ring-closure reaction does not proceed sufficiently, and when the reaction temperature exceeds 200 ° C, the molecular weight of the obtained polyimine decreases. The reaction time in the method of heating the polyamic acid is preferably from 0.5 to 48 hours, and more preferably from 2 to 20 hours.

On the other hand, in the method of adding a dehydrating agent and a dehydration ring-closure catalyst to the solution of the poly-proline in the above (ii), the dehydrating agent may, for example, be an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride. The amount of the dehydrating agent to be used is preferably 0.01 to 20 moles per mole of the polyamic acid structural unit. Further, examples of the dehydration ring-closure catalyst include tertiary amines such as pyridine, trimethylpyridine, lutidine, and triethylamine. However, it is not limited to this. The amount of the dehydration ring-closure catalyst to be used is preferably 0.01 to 10 mols based on 1 mol of the dehydrating agent to be used. The organic solvent used in the dehydration ring-closure reaction may be the same organic solvent as the organic solvent exemplified as the solvent used in the synthesis of the polyamic acid. The reaction temperature of the dehydration ring closure reaction is preferably from 0 to 180 ° C, more preferably from 10 to 150 ° C, and the reaction time is preferably from 0.5 to 20 hours, and more preferably from 1 to 8 hours.

The polyimine obtained in the above method (i) can be directly supplied to a liquid crystal alignment agent, or the obtained polyimine can be purified and then supplied to a liquid crystal alignment agent. On the other hand, in the method (ii), a reaction solution containing polyienimine can be obtained. The reaction solution may be directly supplied to the liquid crystal alignment agent, or may be supplied to the liquid crystal alignment agent after the dehydration agent and the dehydration ring closure catalyst are removed from the reaction solution, and the polyimine may be separated and then supplied to the liquid crystal alignment. The preparation of the agent may be carried out by refining the separated polyimine and then supplying it to the liquid crystal alignment agent. The dehydrating agent and the dehydration ring-closure catalyst are removed from the reaction solution, and a method such as solvent replacement can be used. The separation and purification of the polyimine can be carried out by the same operation as the above separation and purification method of polyglycine.

{other polyorganosiloxanes}

The other polyorganosiloxane of the present invention is a polyorganosiloxane having a structure other than the above-mentioned radiation-sensitive polyorganosiloxane, that is, a polyorganosiloxane having a structure represented by the above formula (A'). Such other polyorganosiloxanes can, for example, be selected from at least a group comprising alkoxydecane and a halogenated decane compound by preferably in a suitable organic solvent in the presence of water and a catalyst. A decane compound (hereinafter also referred to as "raw material decane compound") is synthesized by hydrolysis and condensation.

The starting decane compound used herein may, for example, be tetramethoxy decane, tetraethoxy decane, tetra-n-propoxy decane, tetraisopropoxy decane, tetra-n-butoxy decane or tetra-butoxy Base decane, tetradt-butoxy decane, tetrachloro decane; methyltrimethoxy decane, methyl triethoxy decane, methyl tri-n-propoxy decane, methyl triisopropoxy decane, methyl Tri-n-butoxy decane, methyl tri-tert-butoxy decane, methyl tri-tert-butoxy decane, methyl triphenyloxy decane, methyl trichloro decane, ethyl trimethoxy decane, ethyl Triethoxy decane, ethyl tri-n-propoxy decane, ethyl triisopropoxy decane, ethyl tri-n-butoxy decane, ethyl tri-n-butoxy decane, ethyl tri-tert-butoxy Base decane, ethyl trichloro decane, phenyl trimethoxy decane, phenyl triethoxy decane, phenyl trichloro decane; dimethyl dimethoxy decane, dimethyl diethoxy decane, dimethyl Dichloro decane; trimethyl methoxy decane, trimethyl ethoxy decane, trimethyl chloro decane, etc., and preferably used therein More than one, and particularly preferably used consisting of tetramethoxydecane, tetraethoxydecane, methyltrimethoxydecane, methyltriethoxydecane, phenyltrimethoxydecane, phenyltriethoxy At least one selected from the group consisting of decane, dimethyldimethoxydecane, dimethyldiethoxydecane, trimethylmethoxydecane, and trimethylethoxydecane.

The other polyorganosiloxane of the present invention can be synthesized in the same manner as the above-described method for synthesizing a polyorganosiloxane having an epoxy group, in addition to the above-mentioned starting decane compound.

The polystyrene-equivalent weight average molecular weight measured by gel permeation chromatography for other polyorganosiloxanes is preferably from 1,000 to 100,000, and more preferably from 5,000 to 50,000.

{Use ratio of other polymers}

When the liquid crystal alignment agent of the present invention contains the above-mentioned radiation sensitive polymer and other polymers, the use ratio of the other polymer is preferably 10,000 parts by weight or less based on 100 parts by weight of the radiation sensitive polymer. A more preferable use ratio of the other polymer differs depending on the kind of the polymer contained in the liquid crystal alignment agent of the present invention.

When the liquid crystal alignment agent of the present invention contains a radiation-sensitive polyorganosiloxane and at least one polymer selected from the group consisting of poly-proline and polyimine, a better ratio of the two is The total amount of the polyamic acid and the polyimine is 100 to 5,000 parts by weight, and more preferably 200 to 2,000 parts by weight, based on 100 parts by weight of the radiation-sensitive polyorganosiloxane.

On the other hand, when the liquid crystal alignment agent of the present invention contains a radiation-sensitive polyorganosiloxane and other polyorganosiloxanes, a more preferable ratio of the two is relative to the radiation-sensitive polyorganosiloxane 100. The amount of the other polyorganosiloxane is 100 to 2,000 parts by weight in parts by weight.

[hardener and hardening catalyst]

In order to make the radiation-sensitive polymer, the crosslinking reaction of the radiation-sensitive polyorganosiloxane is more robust, and the above-mentioned hardener and hardening catalyst can be contained in the liquid crystal alignment agent of the present invention, and in order to promote the control of the hardener The hardening reaction can contain the above-mentioned hardening accelerator in the liquid crystal alignment agent of this invention.

As the curing agent, a curing agent which is usually used can be used for curing the curable compound having an epoxy group or a curable composition containing a compound having an epoxy group, and examples thereof include a polyamine and a polycarboxylic acid anhydride. Polycarboxylic acid, etc.

The polyvalent carboxylic acid anhydride may, for example, be an anhydride of cyclohexanetricarboxylic acid or another polyvalent carboxylic acid anhydride.

Specific examples of the cyclohexane tricarboxylic anhydride include cyclohexane-1,3,4-tricarboxylic acid-3,4-anhydride and cyclohexane-1,3,5-tricarboxylic acid-3. 5-anhydride, cyclohexane-1,2,3-tricarboxylic acid-2,3-anhydride, etc. Examples of other polyvalent carboxylic acid anhydrides include 4-methyltetrahydrophthalic anhydride and methyl di Formic anhydride, dodecenyl succinic anhydride, succinic anhydride, maleic anhydride, phthalic anhydride, trimellitic anhydride, compounds represented by the following formula (CA-1), and generally used in the synthesis of polylysine Tetracarboxylic dianhydride,

(In the formula (CA-1), q is an integer from 1 to 20.)

In addition, examples thereof include a Diels Alder reaction product of an alicyclic compound having a conjugated double bond such as α-terpinene or an allo-ocimene, and a hydrogenated product thereof.

Examples of the curing catalyst include a ruthenium hexafluoride compound, a phosphorus hexafluoride compound, and aluminum triacetate. These catalysts are capable of catalyzing the cationic polymerization of epoxy groups generated by heating.

Examples of the hardening accelerator include an imidazole compound, a quaternary phosphorus compound, a quaternary amine compound, and 1,8-diazabicyclo [5.4.0]undecene-7 or an organic acid salt thereof. Azabicycloalkenes; organometallic compounds such as zinc octoate, tin octoate, acetonitrile aluminum complex; boron compounds such as boron trifluoride and triphenyl borate; metal halides such as zinc chloride and tin chloride a high-melting-point-dispersion latent hardening accelerator such as an amine addition-forming accelerator such as an amine diamine amine, an amine and an epoxy resin; or a microcapsule type coated with a quaternary phosphonium salt or the like by a polymer A latent hardening accelerator; an amine salt type latent hardening accelerator; a pyrolysis type thermal cationic polymerization type latent hardening accelerator such as a Lewis acid salt or a Bronsted acid salt.

[epoxy compound]

The epoxy compound can be contained in the liquid crystal alignment agent of the present invention from the viewpoint of further improving the adhesion of the formed liquid crystal alignment film to the surface of the substrate.

Examples of such an epoxy compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and neopentyl Alcohol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl ether, 1,3,5,6-four Glycidyl-2,4-hexanediol, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylamino) Cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N-diglycidyl-benzylamine, N,N - diglycidyl-aminomethylcyclohexane or the like is preferred.

When the liquid crystal alignment agent of the present invention contains an epoxy compound, the content thereof is 100 parts by weight or less, more preferably 40 parts by weight or less, and more preferably the total of the above-mentioned radiation-sensitive polymer and optionally other polymers. 0.1 to 30 parts by weight.

Further, when the liquid crystal alignment agent of the present invention contains an epoxy compound, a base catalyst such as 1-benzyl-2-methylimidazole may be used in combination in order to effectively cause a crosslinking reaction.

[functional decane compound]

In order to further improve the adhesion between the obtained liquid crystal alignment film and the substrate, the above-described functional decane compound can be used. The functional decane compound may, for example, be 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane or 2-aminopropyltri Ethoxy decane, N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxy Decane, 3-hydrazinopropyltrimethoxydecane, 3-mercaptopropylpropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-ethoxyl Carbonyl-3-aminopropyltriethoxydecane, N-triethoxymethylidenepropyltriethylenetriamine, N-trimethoxymethylidenepropyltriethylenetriamine, 10-trimethyl Oxymethalin-1,4,7-triazadecane, 10-triethoxycarbamido-1,4,7-triazadecane, 9-trimethoxycarbamido-3 ,6-diazaindolyl acetate, 9-triethoxycarbamido-3,6-diazaindolyl acetate, N-benzyl-3-aminopropyltrimethoxydecane , N-benzyl-3-aminopropyltriethoxydecane, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltriethoxydecane N-di (oxygen) Ethylene)-3-aminopropyltrimethoxydecane, N-bis(oxyethylidene)-3-aminopropyltriethoxydecane, 3-glycidoxypropyltrimethoxy In the case of decane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, and the like, the tetracarboxylic acid II described in JP-A-63-291922 can be used. A reactant of an anhydride and a decane compound having an amine group, and the like.

When the liquid crystal alignment agent of the present invention contains a functional decane compound, the content thereof is preferably 50 parts by weight or less based on 100 parts by weight of the total of the above-mentioned radiation-sensitive polymer and optionally other polymers, and More preferably, it is 20 parts by weight or less.

[Surfactant]

Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, polyoxyalkylene surfactants, polyoxyalkylene surfactants, and fluorosurfactants. Wait.

When the liquid crystal alignment agent of the present invention contains a surfactant, the content thereof is preferably 10 parts by weight or less, and more preferably 1 part by weight or less based on 100 parts by weight of the total of the liquid crystal alignment agent.

<Liquid alignment agent>

The liquid crystal alignment agent of the present invention contains a radiation sensitive polymer as an essential component as described above, and if necessary, contains other components as needed, and is preferably a solution-like composition in which each component is dissolved in an organic solvent. modulation.

As the organic solvent which can be used for preparing the liquid crystal alignment agent of the present invention, a solvent which dissolves the radiation-sensitive polymer and other components which are optionally used, and which does not react with them, is preferable.

The organic solvent which can be preferably used for the liquid crystal alignment agent of the present invention differs depending on the type of the polymer contained in the liquid crystal alignment agent of the present invention.

When the liquid crystal alignment agent of the present invention contains a radiation-sensitive polyorganosiloxane and at least one polymer selected from the group consisting of poly-proline and polyimine; and in addition to containing a radiation-sensitive polyorgano When the oxane and the at least one polymer selected from the group consisting of poly-proline and polyimine contain other polyorganosiloxanes, a preferred organic solvent can be exemplified as polyamine synthesis. An organic solvent exemplified as the solvent used in the solvent. These organic solvents may be used singly or in combination of two or more.

On the other hand, when the liquid crystal alignment agent of the present invention contains only a radiation-sensitive polyorganosiloxane as a polymer; or contains a radiation-sensitive polyorganosiloxane and other polyorganosiloxane, it does not contain In the case of at least one polymer selected from the group consisting of polyaminic acid and polyimine, examples of preferred organic solvents include N-methyl-2-pyrrolidone, γ-butyrolactone, and γ. - Butyrolactam, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, lactic acid Butyl ester, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol single Diisopropyl ether, diethylene glycol monobutyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol Dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, Diethylene glycol monobutyl ether Diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monobutyl ether acetate, diisobutyl ketone, isoamyl propionate, Isoamyl isobutyrate, diisoamyl ether, ethylene carbonate, propylene carbonate, methanol, ethanol, propanol, butanol, diacetone alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, monoethylene glycol , diethylene glycol, monopropylene glycol, monohexanediol, propylene glycol monomethyl ether, propylene glycol monobutyl ether, methyl acetate, ethyl acetate, ethyl lactate, dimethyl hydrazine, tetramethyl urea, hexamethyl Phosphorus triamine, m-cresol and the like.

A preferred solvent which can be used for the preparation of the liquid crystal alignment agent of the present invention can be obtained by using one or a combination of two or more kinds of the above organic solvents depending on the presence or absence of other polymers and the type of the polymer, and is preferably as described below. In the solid content concentration, the components contained in the liquid crystal alignment agent are not precipitated, and the surface tension of the liquid crystal alignment agent is in the range of 25 mN/m to 40 mN/m.

The solid content concentration of the liquid crystal alignment agent of the present invention, that is, the ratio of the weight of all components other than the solvent in the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent, is selected in consideration of viscosity, volatility, etc., and is preferably 1 ~10% by weight. The liquid crystal alignment agent of the present invention is applied onto the surface of the substrate to form a coating film constituting the liquid crystal alignment film, and when the solid content concentration is less than 1% by weight, it is difficult to obtain a good liquid crystal because the film thickness of the coating film is too small. The case of the alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, the coating film thickness is too large, and it is difficult to obtain a favorable liquid crystal alignment film, and the viscosity of the liquid crystal alignment agent is increased to cause insufficient coating properties. The range of the particularly preferable solid content concentration differs depending on the method used when the liquid crystal alignment agent is applied onto the substrate. For example, when the spin coating method is used, it is particularly preferably from 1.5 to 4.5% by weight. When the printing method is employed, the solid content concentration is particularly preferably in the range of 3 to 9% by weight, and thus the solution viscosity is in the range of 12 to 50 mPa·s. When the ink jet method is employed, the solid content concentration is particularly preferably in the range of 1 to 5% by weight, and thus the solution viscosity is in the range of 3 to 15 mPa·s.

The temperature at which the liquid crystal alignment agent of the present invention is prepared is preferably 0 ° C to 200 ° C, and more preferably 0 ° C to 40 ° C.

<Method of Forming Liquid Crystal Alignment Film>

The liquid crystal alignment agent of the present invention can be preferably used for forming a liquid crystal display element which can be used for a liquid crystal alignment film, a TN type, an STN type, a lateral electric field method (IPS type) or a VA type by a photo-alignment method. When the liquid crystal display element of the present invention is used for a liquid crystal display device of a TN type, an STN type or a lateral electric field type, particularly when used in a liquid crystal display element of a lateral electric field type, the effect of the present invention can be maximized. Preferably.

In order to form a liquid crystal alignment film by using the liquid crystal alignment agent of the present invention, a method of forming a coating film by applying the liquid crystal alignment agent of the present invention onto a substrate and irradiating the coating film with radiation may be employed.

When the liquid crystal alignment agent of the present invention is used for a liquid crystal display device of a TN type, an STN type or a VA type, first, two substrates each having a patterned transparent conductive film are provided as a pair, and each of them is transparent. The liquid crystal alignment agent of the present invention is applied onto the conductive film forming surface to form a coating film. On the other hand, when the liquid crystal alignment agent of the present invention is used for a liquid crystal display device of a horizontal electric field type, a substrate having an electrode having a transparent conductive film or a metal film patterned on one surface and an electrode not provided with an electrode The substrate is used as a pair, and the liquid crystal alignment agent of the present invention is applied to the surface of the comb-shaped electrode and the surface of the counter substrate, respectively, to form a coating film.

In either case, as the substrate, for example, glass such as floating glass or soda lime glass, polyethylene terephthalate, polybutylene terephthalate, polyether oxime, or polycarbonate can be used. A transparent substrate or the like formed of a plastic substrate such as an ester. As the transparent conductive film, for example, an ITO film formed of In ₂ O ₃ —SnO ₂ , a NESA (registered trademark) film formed of SnO ₂ , or the like can be used. As the metal film, for example, a film made of a metal such as chromium can be used. The formation pattern of the transparent conductive film and the metal film can be, for example, a method of forming a pattern by a method of performing photolithography, a sputtering method, or the like after forming a transparent conductive film having no pattern, and a desired method for forming a transparent conductive film. The method of pattern mask, etc.

When the liquid crystal alignment agent is applied onto the substrate, a functional decane compound, titanate or the like may be applied to the substrate and the electrode in advance in order to further improve the adhesion between the substrate, the conductive film or the electrode and the coating film.

The method of applying a liquid crystal alignment agent to a substrate is preferably carried out by an appropriate coating method such as an offset printing method, a spin coating method, a roll coating method, or an inkjet printing method, followed by preheating the coated surface (pre-heating) Baking), and then firing (post-baking) to form a coating film. The prebaking conditions are, for example, 0.1 to 5 minutes at 40 to 120 ° C, and the post-baking conditions are preferably 120 to 300 ° C, more preferably 150 to 250 ° C, and preferably 5 to 200. Minutes, preferably 10 to 100 minutes. The film thickness after the post-baking is preferably 0.001 to 1 μm, and more preferably 0.005 to 0.5 μm.

The liquid crystal alignment ability is imparted by irradiating the coating film thus formed with linearly polarized or partially polarized radiation or unpolarized radiation. Here, as the radiation, for example, ultraviolet rays and visible rays containing light having a wavelength of 150 to 800 nm can be used, and ultraviolet rays containing light having a wavelength of 300 to 400 nm are preferable. When the radiation to be used is linearly polarized or partially polarized, irradiation may be performed from a direction perpendicular to the substrate surface, and irradiation may be performed from the oblique direction in order to impart a pretilt angle, or they may be combined. When irradiating non-polarized radiation, the direction of irradiation must be an oblique direction.

As the light source to be used, for example, a low pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser or the like can be used. The ultraviolet light in the preferred wavelength region can be obtained by a method in which the light source is used in combination with, for example, a filter, a diffraction grating, or the like.

The irradiation amount of radiation, preferably 1J / m ² or more 10,000J / m ² or less, and more preferably 10 ~ 3,000J / m ^2. In addition, when a liquid crystal alignment ability is imparted to a coating film formed of a conventionally known liquid crystal alignment agent by a photo-alignment method, a radiation irradiation amount of 10,000 J/m ² or more is required. In the case of using the liquid crystal alignment agent of the present invention, even when the amount of radiation irradiation in the photo-alignment method is 3,000 J/m ² or less, and further 1,000 J/m ² or less, it is possible to impart good liquid crystal alignment ability and contribute to The productivity of the liquid crystal display element is improved and the manufacturing cost is lowered.

<Method of Manufacturing Liquid Crystal Display Element>

The liquid crystal display element formed using the liquid crystal alignment agent of the present invention can be produced, for example, as follows.

First, a pair of substrates on which a liquid crystal alignment film is formed as described above is prepared, and a liquid crystal cell having a structure in which liquid crystal is sandwiched between the pair of substrates is manufactured. In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example.

The first method is a previously known method. First, the two substrates are disposed opposite to each other with a gap (cell gap) therebetween, and the respective liquid crystal alignment films are opposed to each other, and the peripheral portions of the two substrates are bonded together using a sealant, and the substrate surface and the sealant are bonded together. After the liquid crystal is injected and filled in the divided cell gap, the injection hole is closed, whereby the liquid crystal cell can be manufactured.

As a second method, it is called a method of ODF (One Drop Fill). Wherein, for example, an ultraviolet curable sealing material is applied to a predetermined portion of one of the two substrates on which the liquid crystal alignment film is formed, and liquid crystal is dropped on a plurality of places on the liquid crystal alignment film surface, and then the other substrate is bonded to each other. The liquid crystal alignment film is opposed to each other, and the liquid crystal is pressed against the substrate, and then the entire surface of the substrate is irradiated with ultraviolet rays to harden the sealing agent, whereby the liquid crystal cell can be manufactured.

Whichever method is employed, it is desirable to heat the liquid crystal cell to a temperature at which the liquid crystal used is in an isotropic phase, and then slowly cool to room temperature, thereby removing the flow alignment when the liquid crystal is filled.

Then, 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. Here, a desired liquid crystal display element can be obtained by appropriately adjusting the angle formed by the polarization direction of the linearly polarized radiation irradiated on the two substrates forming the liquid crystal alignment film and the angle between each of the substrates and the polarizing plate.

The sealing agent may, for example, be an epoxy resin containing an alumina ball as a separator and a curing agent.

Examples of the liquid crystal include nematic liquid crystal and smectic liquid crystal. A liquid crystal having positive dielectric anisotropy is preferable, and for example, a biphenyl liquid crystal, a phenylcyclohexane liquid crystal, an ester liquid crystal, a terphenyl liquid crystal, a biphenyl cyclohexane liquid crystal, or a pyrimidine can be used. Liquid crystal, dioxane liquid crystal, bicyclooctane liquid crystal, cubic liquid crystal, and the like. Further, in the liquid crystal, cholesteric liquid crystal such as cholesteryl cholesteryl, cholesteryl phthalate or cholesteryl carbonate may be further added; as the trade names "C-15" and "CB-15" (above, A chiral agent sold by Merck Co., Ltd.; a strong dielectric liquid crystal such as p-methoxybenzylidene-p-amino-2-methylbutyl cinnamate.

The polarizing plate used for the outer side of the liquid crystal cell is a polarizing plate formed by sandwiching a polarizing film with a cellulose acetate protective film, or a polarizing plate formed by the H film itself, and the polarizing film is formed by stretching and aligning polyvinyl alcohol. The result of absorbing iodine is called "H film".

In the liquid crystal display device of the present invention thus produced, since the liquid crystal molecules have excellent alignment control power, the display characteristics are excellent.

[Examples]

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

The weight average molecular weight Mw in the following synthesis examples is a polystyrene-converted value measured by gel permeation chromatography under the following conditions.

Pipe column: Tosoh (stock) system, TSKgel GRCXLII

Solvent: tetrahydrofuran

Temperature: 40 ° C

Pressure: 68kgf/cm ²

<Synthesis Example of Polyorganooxane having an Epoxy Group> Synthesis Example ES-1

In a reaction vessel having a stirrer, a thermometer, a dropping funnel, and a reflux condenser, 100.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane as a raw material decane compound was added as a solvent. 500 g of methyl isobutyl ketone and 10.0 g of triethylamine as a catalyst were mixed at room temperature.

Next, 100 g of deionized water was dropped from the dropping funnel over 30 minutes, and then mixed under reflux, and reacted at 80 ° C for 6 hours. After completion of the reaction, the organic layer was taken out, washed with a 0.2% by weight aqueous solution of ammonium nitrate until the washed water was neutral, and then the solvent and water were distilled off under reduced pressure to give an epoxy group as a viscous transparent liquid. Polyorganosiloxane (ES-1).

The 1 H-NMR analysis of the polyorganosiloxane having an epoxy group revealed that an epoxy group-based peak having the same theoretical strength was obtained in the vicinity of the chemical shift (δ) = 3.2 ppm, whereby it was confirmed in the reaction. A side reaction in which no epoxy group is produced.

The polyorganosiloxane (ES-1) having the epoxy group had an Mw of 2,200 and an epoxy equivalent of 186 g/mole.

Synthesis Examples ES-2 and ES-3

The polyorganosiloxane (ES-2) and (ES-3) having an epoxy group as a viscous transparent liquid were obtained in the same manner as in the synthesis example ES-1 except that the raw materials to be added were as shown in Table 1.

The Mw and epoxy equivalents of these epoxy group-containing polyorganosiloxanes are shown in Table 1.

In addition, in Table 1, the abbreviation of a raw material decane compound has the following meaning respectively.

ECETS: 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane

MTMS: methyltrimethoxydecane

PTMS: Phenyltrimethoxydecane

Table 1. Synthesis of polyorganosiloxanes with epoxy groups

<Synthesis Example of Compound (A)>

According to the following Scheme 1, the compound represented by the above formula (A-1) (hereinafter referred to as "compound (A-1)") and the compound represented by the above formula (A-2) (hereinafter referred to as " Compound (A-2)").

Synthesis Example A-1

An oil dispersion of NaH (in terms of NaH to 1.2 equivalents) was taken in a three-necked flask equipped with a reflux condenser and calcium chloride, and washed with hexane, and then anhydrous tetrahydrofuran (THF) was added. 1.1 equivalent of 2-hydroxybenzophenone was dissolved in THF and stirred at room temperature for 15 minutes. After the end of the production of hydrogen from the reaction system, the calcium chloride tube was exchanged with argon gas, and then 1.0 equivalent of methyl 3-(bromomethyl)benzoate was dissolved in THF, and stirred at room temperature for 1 hour. Further, reflux was carried out for 2 hours. Then, after cooling to room temperature, the THF was removed by an evaporator. Water and ethyl acetate were added to the residue, and the organic layer was separated. Next, in order to remove unreacted 2-hydroxybenzophenone, the organic layer was washed with an aqueous NaOH solution having a concentration of 1 mol/L. Further, the organic layer was washed successively with water and a saturated aqueous solution of sodium chloride, and dried over anhydrous magnesium sulfate, and the residue obtained by removing the solvent under reduced pressure was subjected to silica gel column chromatography (developing solvent: containing hexane and The mixed solvent of ethyl acetate (hexane: ethyl acetate = 10:1 (capacity ratio)) was separated, and the solvent was removed from the fraction to obtain 3-((2-benzopyrene) as an intermediate. Methyl)methyl)benzoate (compound (A-1a)) (yield 60%).

Next, the compound (A-1a) was dissolved in a mixed solvent containing methanol and THF (methanol: THF = 10:1 (volume ratio)) to form a solution, and a potassium hydroxide aqueous solution having a concentration of 2 mol/L was added thereto. The amount of addition was converted to 2 equivalents of potassium hydroxide, and the mixture was stirred at 50 ° C overnight to carry out a reaction. After the reaction was completed, ether and water were added to the reaction mixture, and the aqueous phase was separated. After adding hydrochloric acid to the aqueous phase to be acidic, it was washed successively with water and saturated brine, and then the solid obtained by distilling off the solvent under reduced pressure from a mixed solvent containing THF and hexane (THF:hexane = Recrystallization from 10:1 (volume ratio)) gave Compound (A-1) (yield: 83%).

Synthesis Example A-2

In the above Synthesis Example A-1, except that 1.0 equivalent of methyl 4-(bromomethyl)benzoate was used instead of methyl 3-(bromomethyl)benzoate, the same procedure as in Synthesis Example A-1 was obtained. Methyl 4-((2-benzylidenephenoxy)methyl)benzoate (compound (A-2a)) as an intermediate in a yield of 55%, which was used to give compound (A-2) The rate is 82%).

<Comparative Synthesis Example of Carboxylic Acid> Comparative Synthesis Example 1

The comparative carboxylic acid (R-1) was synthesized according to the following Scheme 2.

In a 200 mL three-necked flask, 11.21 g of 4-hydroxychalcone, 8.35 g of ethyl bromoacetate, 13.8 g of potassium carbonate and 100 mL of dimethylacetamide were added, and the mixture was stirred at 120 ° C for 7 hours to carry out a reaction. After the reaction was completed, the reaction solution was cooled to room temperature, and then 100 mL of ethyl acetate was added. After the organic layer was washed with water, the solvent was removed under reduced pressure, and the obtained solid was recrystallized from a mixed solution of ethanol and water (ethanol: water = 4:1 (capacity ratio)) to obtain 11.4 g as an intermediate. Compound (R-1a).

Next, 6.2 g of the above compound (R-1a), 2 g of sodium hydroxide, 200 mL of ethanol, and 50 mL of water were placed in a 500 mL three-necked flask equipped with a condenser, and the mixture was stirred under reflux for 3 hours to carry out a reaction. After completion of the reaction, the reaction mixture was cooled, and then diluted with hydrochloric acid to make it acidic. Then, 500 mL of ethyl acetate was added to carry out liquid separation. After the obtained organic layer was washed with water, the solvent was removed under reduced pressure to give Compound (R-1).

<Synthesis Example of Radiation-Tensible Polyorganooxane> Synthesis Example S-1

In a 100 mL three-necked flask, 9.3 g of the polyorganosiloxane (ES-1) having an epoxy group obtained in the above Synthesis Example ES-1, 26 g of methyl isobutyl ketone, and 7.64 g were added as a carboxylic acid (A). The compound (A-1) obtained in the above Synthesis Example A-1 and 0.10 g of UCAT 18X (trade name, quaternary ammonium salt of SAN-APRO Co., Ltd.) were stirred at 80 ° C for 12 hours to carry out a reaction. After the completion of the reaction, methanol was added to the reaction mixture, and the resulting precipitate was recovered, dissolved in ethyl acetate, and the resulting solution was washed three times with water, and then the solvent was evaporated to give 10 g of a s. Oxane (S-1). The weight average molecular weight Mw of the radiation sensitive polyorganosiloxane (S-1) was 5,600.

Synthesis Examples S-2 and S-3

In the above Synthesis Example S-1, the types and amounts of the polyorganosiloxane and the carboxylic acid (A) having an epoxy group were respectively as shown in Table 2, and were the same as in Synthesis Example S-1. The radiation sensitive polyorganosiloxanes (S-2) and (S-3) were obtained. The yields of these sensitizing radiopolyorganosiloxanes and the weight average molecular weight Mw are collectively shown in Table 2.

<Comparative Synthesis Example of Radiation-Tensible Polyorganooxane> Synthesis Example RS-1

In the above Synthesis Example S-1, the amount of the polyorganosiloxane (ES-1) having an epoxy group was 11.4 g, and 3.52 g of the compound obtained in the above Synthesis Example R-1 (R-1) was used. In the same manner as in the synthesis example S-1, 9.1 g of a radiation-sensitive linear polyorganosiloxane (RS-1) was obtained instead of the compound (A-1). The weight average molecular weight Mw of the radiation-sensitive linear polyorganosiloxane (RS-1) is shown in Table 2.

Table 2. Synthesis of radiation sensitive polyorganosiloxane

<Synthesis Example of Other Polymers> [Synthesis Example of Polylysine] Synthesis Example PA-1

19.61 g (0.1 mol) of cyclobutane tetracarboxylic dianhydride and 21.23 g (0.1 mol) of 4,4'-diamino-2,2'-dimethylbiphenyl were dissolved in 367.6 g of N-A In the base-2-pyrrolidone, the reaction was carried out for 6 hours at room temperature. Next, the reaction mixture was poured into a very large excess of methanol to precipitate a reaction product. The precipitate was recovered, washed with methanol, and dried under reduced pressure at 40 ° C for 15 hours to obtain 35 g of polyamine (PA-1).

Synthesis Example PA-2

22.4 g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride and 14.23 g (0.1 mol) of cyclohexane bis(methylamine) were dissolved in 329.3 g of N-methyl-2- In pyrrolidone, the reaction was carried out at 60 ° C for 6 hours. Next, the reaction mixture was poured into a very large excess of methanol to precipitate a reaction product. The precipitate was washed with methanol and dried under reduced pressure at 40 ° C for 15 hours to obtain 32 g of polyamine (PA-2).

A part of the polyamine acid (PA-2) was supplied to the liquid crystal alignment agent in the examples described later, and the remainder was supplied to the synthesis of the following polyimine.

[Synthesis Example of Polyimine] Synthesis example PI-1

17.5 g of the polylysine (PA-2) obtained in the above Synthesis Example PA-2 was added, and 232.5 g of N-methyl-2-pyrrolidone, 3.8 g of pyridine and 4.9 g of acetic anhydride were added thereto at 120 ° C. The ruthenium imidization reaction was carried out for 4 hours. The resulting reaction mixture was poured into a very large excess of methanol to precipitate a reaction product. The precipitate was washed with methanol and dried under reduced pressure for 15 hours to give 15 g of polyimine (PI-1).

Example 1 <Modulation of liquid crystal alignment agent>

100 parts by weight of the radiation-sensitive polyorganosiloxane (S-1) obtained in the above Example S-1 and 1,000 parts by weight of the poly-proline (PA) obtained in the above Synthesis Example PA-1 as another polymer -1) dissolved in a mixed solvent (N-methyl-2-pyrrolidone: butyl cellosolve = 50:50 (weight ratio)) formed of N-methyl-2-pyrrolidone and butyl cellosolve A solution having a solid concentration of 3.0% by weight was formed. The solution was filtered using a filter having a pore size of 1 μm to prepare a liquid crystal alignment agent.

<Manufacture of liquid crystal display element>

The liquid crystal alignment agent prepared by applying the above-described prepared liquid crystal alignment agent to each other on the electrode formation surface of the glass substrate including the chrome metal electrode patterned in a comb shape and the opposite glass substrate on which the electrode is not provided It was prebaked on a hot plate at 80 ° C for 1 minute, and then post-baked at 200 ° C for 1 hour in an oven which had been subjected to nitrogen substitution in the tank to form a coating film having a film thickness of 0.1 μm. Next, using a Hg-Xe lamp and a Glan Taylor prism, the surface of the coating film was irradiated with a polarized ultraviolet ray having a wavelength of 313 nm at 600 J/m ² from the normal direction of the substrate to obtain a pair of substrates having a liquid crystal alignment film.

By screen printing, the outer periphery of the surface of the liquid crystal alignment film is formed on the substrate having the chromium metal electrode in the pair of substrates, and an epoxy resin adhesive having an alumina ball having a diameter of 5.5 μm is applied thereto. The liquid crystal alignment film of the substrate was opposed to each other, pressed, and heated at 150 ° C for 1 hour to thermally harden the adhesive. Next, the liquid crystal injection port was filled with a liquid crystal MLC-7028 manufactured by Merck, and the liquid crystal injection port was sealed with an epoxy-based adhesive. Further, in order to eliminate the flow alignment at the time of liquid crystal injection, it was heated at 150 ° C and then slowly cooled to room temperature. Next, a polarizing plate is bonded to both outer surfaces of the substrate so that the polarization directions thereof are orthogonal to each other and orthogonal to the projection direction of the ultraviolet light axis of the liquid crystal alignment film on the substrate surface, thereby manufacturing a liquid crystal display element of a horizontal electric field type .

<Evaluation of Liquid Crystal Display Element>

The liquid crystal display element was evaluated by the following method. The evaluation results are shown in Table 3.

(1) Evaluation of liquid crystal alignment

When the voltage of 5 V was applied to the liquid crystal display element manufactured as described above by an optical microscope, an abnormal region having no change in brightness was observed, and when no abnormal region was observed, the liquid crystal alignment property was evaluated as "good". When an abnormal region was observed, the liquid crystal alignment property was evaluated as "not good".

(2) Evaluation of voltage retention rate

With respect to the liquid crystal display element manufactured above, a voltage of 5 V was applied at 60 ° C for an application time of 60 μsec and an interval of 167 msec, and then the voltage holding ratio from the release of the application to 167 msec was measured. The measuring device was manufactured by Dongyang Corporation, VHR-1.

Examples 2 to 8 and Comparative Example 1

A liquid crystal alignment agent was prepared in the same manner as in Example 1 except that the type of the radiation-sensitive polyorganosiloxane and the kind and amount of other polymers were changed as described in Table 1, respectively, and a transverse electric field method was produced. The liquid crystal display element was evaluated. The evaluation results are shown in Table 3.

Further, in Comparative Example 1, the amount of polarized ultraviolet rays when the liquid crystal display element was produced was 1,000 J/m ² .

Table 3. Modulation and evaluation of liquid crystal alignment agents

Claims (5)

A liquid crystal alignment agent characterized by containing a radiation sensitive polyorganosiloxane: Further, the liquid crystal alignment agent optionally further contains a group consisting of polyphosphoric acid, polyimine, and polyorganosiloxane, in an amount of 10,000 parts by weight or less based on 100 parts by weight of the above-mentioned radiation-sensitive polyorganosiloxane. At least one polymer selected from the group, and the polymer does not contain a structure represented by the formula (A'), and the above-mentioned radiation-sensitive polyorganosiloxane is a polyorganosiloxane having an epoxy group and the following formula (A) The reaction product of the compound shown, In the formula (A), R is independently an alkyl group having 1 to 4 carbon atoms, a halogen atom or a cyano group, n1 is an integer of 0 to 3, n2 is an integer of 0 to 4, and R ¹ is the following formula (R- 1) the group, R ² and R ³ is a group of formula (R-3) shown in the illustrated, but of formula (a) is present in Z of a carboxyl group, the other is a hydrogen atom, *-X ² -R ⁶ -Z (R-3) X ¹ in the formula (R-1) is a single bond, -O- ⁺ , -COO- ⁺ or -OCO- ⁺ (but with "+" The linking bond is R ⁴ side), R ⁴ is a single bond, a methylene group or an alkylene group having 2 to 5 carbon atoms, R is an alkyl group having 1 to 4 carbon atoms, a halogen atom or a cyano group, and n3 is An integer of 0 to 4, where X ² in the formula (R-3) is a single bond, -O- ⁺ , -COO- ⁺ or -OCO- ⁺ (but the connection key with "+" is the R ⁶ side) , R ⁶ is a single bond, a methylene group or alkylene group having a carbon number of 2 to 5, of formula (R-1) and (R-3) in the "*" each represent a bond. The liquid crystal alignment agent of claim 1, which comprises at least one polymer selected from the group consisting of polyamic acid and polyimine, wherein the polymer does not have the above formula (A') The structure represented. The liquid crystal alignment agent of claim 1, which comprises a polyorganosiloxane, wherein the polyorganosiloxane does not have the structure represented by the above formula (A'). A method of forming a liquid crystal alignment film, comprising the steps of: coating a liquid crystal alignment agent according to any one of claims 1 to 3 on a substrate to form a coating film, and irradiating the coating film with radiation. A liquid crystal display element comprising a liquid crystal alignment film formed by the liquid crystal alignment agent according to any one of claims 1 to 3.