TWI554555B - A liquid crystal alignment film, a liquid crystal alignment film, and a liquid crystal display device - Google Patents

Description

Method for producing liquid crystal alignment film, liquid crystal alignment film and liquid crystal display element

The present invention relates to a method for producing a liquid crystal alignment film, a liquid crystal alignment film obtained by the production method, and a liquid crystal display element using the liquid crystal alignment film.

Liquid crystal display elements are known as light, thin, and low-power display devices, and have been used in large-scale television applications in recent years, and have achieved remarkable development. The liquid crystal display element is formed by, for example, holding a liquid crystal layer by a pair of substrates having transparent electrodes. Further, in the liquid crystal display device, an organic film made of an organic material is used as a liquid crystal alignment film in order to bring the liquid crystal into a desired alignment state between the substrates.

In other words, the liquid crystal alignment film indicates a constituent member of the liquid crystal display element, and is formed on a surface that is in contact with the liquid crystal of the substrate on which the liquid crystal is held, and serves to align the liquid crystal in a predetermined direction between the substrates. The liquid crystal alignment film has a function of controlling the pretilt angle of the liquid crystal in addition to aligning the liquid crystal to a certain direction such as a direction in which the substrates are parallel. The ability to control the alignment of the liquid crystal in the liquid crystal alignment film (hereinafter referred to as the alignment control energy) is indicated by the alignment treatment of the organic film constituting the liquid crystal alignment film.

Nowadays, the main liquid crystal alignment film used in the industry is a polyimine composed of a solution of a polyimide precursor (polyamic acid, polyphthalate) or polyimine. Liquid crystal alignment treatment coating It is produced by film formation on a substrate.

Further, when the liquid crystal is horizontally aligned, parallel-aligned, or obliquely aligned, etc., the surface of the substrate is subjected to surface stretching treatment by rubbing. In addition, a method of anisotropic optical reaction by polarized ultraviolet light irradiation or the like has been proposed, and in recent years, a method toward industrialization has been reviewed.

The rubbing treatment is an organic film such as polyvinyl alcohol or polyamide or polyimide on a substrate, and the surface thereof is wiped (frictionally) in a certain direction with a cloth such as cotton, nylon or polyester to make a liquid crystal. A method of aligning the direction (friction direction) after wiping. This rubbing method is simple and can realize the alignment state of the relatively stable liquid crystal, and thus is used in the process of the conventional liquid crystal display element.

However, the rubbing method of wiping the surface of the liquid crystal alignment film composed of polyimide or the like has a problem of generating dust or static electricity. In addition, due to the high definition of the liquid crystal display element in recent years, the unevenness caused by the switching of the active element on the substrate or the liquid crystal driving, the surface of the liquid crystal alignment film cannot be uniformly wiped with a cloth, and uniformity may not be achieved. LCD alignment.

The alignment method of the liquid crystal alignment film which replaces the rubbing treatment is actively reviewing the photoalignment method. For example, a photo-alignment method using an anisotropic photochemical reaction such as polarized ultraviolet ray irradiation has been proposed, and in recent years, a method toward industrialization has been reviewed.

There are several methods for the photo-alignment method. Generally, anisotropy is formed on the surface of the organic film constituting the liquid crystal alignment film by linearly polarized or collimated light, and the liquid crystal is aligned according to the anisotropy.

The main specific optical alignment method, for example, has a decomposed photo-alignment method for human beings. Known. The decomposition-type photo-alignment method is, for example, that a polarized ultraviolet ray is irradiated onto a polyimide film, and an anisotropic decomposition occurs by utilizing a polarization dependence of ultraviolet absorption of a molecular structure, and the polyimine is not decomposed. A method of aligning liquid crystals (see, for example, Patent Document 1).

Further, a dimerization type photoalignment method is also known. The dimerization type photo-alignment method refers to the use of, for example, polyvinyl cinnamate to irradiate polarized ultraviolet rays, and a dimerization reaction occurs in the double bond portions of two side chains parallel to the polarized light to align the liquid crystal with the polarization direction. A method of the direction of the orthogonality (see, for example, Non-Patent Document 1).

As described above, the alignment treatment method of the liquid crystal alignment film by the photo-alignment method does not require rubbing, and there is no doubt that dust or static electricity is generated. Moreover, the alignment treatment method of the liquid crystal alignment film by the photo-alignment method can be applied to an industrial production process even if the substrate of the liquid crystal display element having the uneven surface is subjected to the alignment treatment.

Further, the display characteristics of the liquid crystal display element are improved by using a method of changing the structure of polyacrylic acid, polyamidomate, polythenimine or the like, polyglycolic acid, polyglycolate having different blending characteristics, A method such as polyimide or a method of adding an additive, etc., improves liquid crystal alignment property, electrical characteristics, etc., and controls a pretilt angle. For example, it is proposed to use a polymer having a specific structure as a side chain (see Patent Document 2).

However, as the performance of the liquid crystal display element is increased, the area is increased, and the power consumption of the display device is reduced, the characteristics required for the liquid crystal alignment film are also severe. When the conventional liquid crystal alignment treatment agent is used in Patent Document 2 or the like, the scorch characteristics are insufficient, and the residual image of the liquid crystal alignment performance is changed by AC (alternating current) driving. question.

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 3893659

[Patent Document 2] Japanese Patent Publication No. 2001-517719

[Non-patent literature]

[Non-Patent Document 1] M. Shadt et al., Jpn. J. Appl. Phys. 31, 2155 (1992)

[Summary of the Invention]

In the photo-alignment method, the alignment treatment method of the liquid crystal display element has a large advantage in that it does not require a rubbing step as compared with the conventional rubbing treatment used in the industry.

However, in the decomposition type photo-alignment method described in Patent Document 1, the polyimide film is irradiated with ultraviolet light of a high-pressure mercury lamp of 500 W for 60 minutes or the like, and it takes a long time and a large amount of ultraviolet rays to be irradiated.

Further, in the dimerization type photoalignment method, a large amount of ultraviolet irradiation of several to several tens of joules (J) is sometimes required. Further, when the amount of ultraviolet rays irradiated to the liquid crystal alignment film is only about several tens to several hundreds of microjoules (mJ), in order to obtain uniform liquid crystal alignment, it is necessary to introduce a large amount of photoreactive groups. The amount of imports. Therefore, even after ultraviolet irradiation, unreacted groups may remain, and the liquid crystal display element using such a liquid crystal alignment film may react with an unreacted group by a backlight or external light, and may have a change in the alignment state of the liquid crystal. problem. Thus, a large amount of ultraviolet ray irradiation or an unreacted photoreactive group remains due to a low photoreaction efficiency of the organic film used for the liquid crystal alignment film.

In other words, it is necessary to develop an organic film material for a liquid crystal alignment film having high photoreaction efficiency and to develop a method for producing a liquid crystal alignment film which can improve photoreaction efficiency.

An object of the present invention is to provide a method for producing a liquid crystal alignment film which can realize high-efficiency photoreaction efficiency, which can perform high-efficiency alignment treatment, and a liquid crystal display element including the obtained liquid crystal alignment film.

Moreover, the object of the present invention is to provide a method for producing a liquid crystal alignment film using a polyimide precursor obtained by using a novel diamine, and using the obtained liquid crystal alignment film, which can reduce variations in liquid crystal alignment properties caused by AC driving. A liquid crystal display element having excellent afterimage characteristics.

As a result of intensive research, the inventors have completed the present invention of the technical requirements of the following (1) to (12).

(1) A method for producing a liquid crystal alignment film, characterized in that a film containing a photoreactive group of a polyimide or a polyimide precursor is formed on a substrate, and the front film side is heated while being irradiated with a polarized light. Ultraviolet light, which is made of a polymer containing a polyimide precursor on the substrate. Liquid crystal alignment film.

(2) The method for producing a liquid crystal alignment film according to the above item (1), wherein the polyimine precursor having a photoreactive group contains a repeating unit represented by the following formula [1] and is represented by the following formula [2] Repeat unit, (In the formula [1], R ₁ represents a divalent organic group, R ₂ represents a tetravalent organic group, R ₃ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms, and R ₄ represents a hydrogen atom or a carbon number. 1 to 6 organic groups. n ₁ indicates a positive integer) (In the formula [2], R ₅ represents a divalent organic group constituting a photoreactive group. R ₆ represents a tetravalent organic group, R ₇ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms, and R ₈ represents A hydrogen atom or an organic group having 1 to 6 carbon atoms. n ₂ represents a positive integer).

(3) The method for producing a liquid crystal alignment film according to the above (1), wherein the polyimine precursor having a photoreactive group contains a repeating unit represented by the above formula [1] and is represented by the following formula [3] Repeat unit, (In the formula [3], R ₉ represents a divalent organic group, and R ₁₀ represents a divalent organic group constituting a photoreactive group. n ₃ represents a positive integer).

(4) The method for producing a liquid crystal alignment film according to the above item (1), wherein the polyimine precursor having a photoreactive group is a diamine component and a tetracarboxylic acid containing a diamine represented by the following formula [4] Acid dianhydride is obtained by polycondensation, (In the formula [4], X ¹ represents a single bond or an alkylene group having 1 to 5 carbon atoms (but a non-adjacent -CH ₂ - may be substituted into an ether bond, an ester bond or a guanamine bond), and the X ² system Represents -OCO-CH=CH- or -CH=CH-COO-, X ³ represents a single bond, an alkylene group having a carbon number of 1 to 10 or a divalent benzene ring, and X ⁴ represents a single bond, -OCO-CH =CH- or -CH=CH-COO-, X ⁵ represents a single bond or an alkylene group having 1 to 6 carbon atoms (but not adjacent -CH ₂ - may be substituted with an ether bond, an ester bond or a guanamine bond) In the formula [4], one or more cinnamoyl groups are contained.

(5) The method for producing a liquid crystal alignment film according to any one of the above items, wherein the film has a thickness of 5 to 300 nm.

(6) The method for producing a liquid crystal alignment film according to any one of the above aspects, wherein the content of the photoreactive group-containing polyimine precursor is 0.1 to 30% by mass, and the solvent is used. Liquid crystal alignment treatment agent formation The aforementioned film.

(7) The method for producing a liquid crystal alignment film according to any one of the above aspects, wherein the temperature of the heating is selected from the group consisting of the above-mentioned photoreactive group-containing polyimide precursor does not become polyfluorene. The temperature in the temperature range of the imine.

(8) The method for producing a liquid crystal alignment film according to any one of the preceding claims, wherein the heating temperature is in a range of from 50 ° C to 300 ° C.

(9) The method for producing a liquid crystal alignment film according to any one of the above (1), wherein the heating temperature is in a range of from 80 °C to 250 °C.

(10) The method for producing a liquid crystal alignment film according to any one of the items (1) to (9), wherein the ultraviolet ray irradiation amount is 100 to 1000 mJ.

(11) A liquid crystal alignment film produced by the method for producing a liquid crystal alignment film according to any one of the items (1) to (10) above.

(12) A liquid crystal display element characterized by having the liquid crystal alignment film of the above (11).

According to the present invention, it is possible to provide a method for producing a liquid crystal alignment film which can realize high photoreaction efficiency and can perform high-efficiency alignment treatment. The liquid crystal display element using the obtained liquid crystal alignment film has high manufacturing efficiency, and has few photoreactive residues in the liquid crystal alignment film, and it is less likely to cause a change in the alignment state of the liquid crystal even when used for a long period of time.

The present invention does not require friction on the liquid crystal alignment film. Moreover, a photoreaction with high reaction efficiency of a polymer film containing a polyimide precursor is realized. A highly efficient liquid crystal alignment film is produced.

Further, in the present invention, a polyimine precursor obtained from a novel diamine, a liquid crystal display element having a liquid crystal alignment film, can reduce a change in liquid crystal alignment property caused by AC driving, and the liquid crystal alignment property is not easily changed, and is difficult to be used. Generate afterimages.

[Formation of the Invention]

The method for producing a liquid crystal alignment film of the present invention is a method of performing an alignment treatment by polarized light irradiation using a polymer film containing a polyimide precursor. For example, a film of a polyphthalate derivative having a photoreactive group is formed on a substrate, followed by heating to maintain a heated state while irradiating the film surface with polarized ultraviolet rays to form a polyphthalate derivative on the substrate. A liquid crystal alignment film formed.

The polyimine precursor used in the method for producing a liquid crystal alignment film of the present invention contains a repeating unit represented by the following formula [1] and a repeating unit represented by the following formula [2] and the following formula [3] ] indicates at least one of the repeating units. The repeating unit represented by the following formula [2] and formula [3] has a photoreactive group.

In the above formula [1], R ₁ is a divalent organic group. R ₂ represents a tetravalent organic group. R ₃ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms. R ₄ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms. The n ₁ system represents a positive integer.

The repeating unit represented by the above formula [1] can be obtained by using a diamine component represented by the following formula [1-A] and a tetracarboxylic dianhydride component of an acid anhydride of a tetracarboxylic acid represented by the following formula [1-B].

In the above formula [1-A] and formula [1-B], R ₁ and R ₂ are the same as R ₁ and R ₂ in the above formula [1].

Specific examples of the diamine component represented by the above formula [1-A] include p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, and 2,5-dimethyl-pair. -phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diamino Phenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoisophthalic acid Phenol, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diamine Biphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobiphenyl, 3,3'-difluoro- 4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-di Aminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-di Aminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4' -diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodi Phenyl ether, 4,4'-sulfonyldiphenylamine, 3,3'-sulfonyldiphenylamine, bis(4-aminophenyl)decane, Bis(3-aminophenyl)decane, dimethyl-bis(4-aminophenyl)decane, dimethyl-bis(3-aminophenyl)decane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 4,4'-diaminodiphenylamine, 3,3'-diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2, 2'-Diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl(4,4'-diaminodiphenyl)amine, N-methyl (3, 3'-Diaminodiphenyl)amine, N-methyl(3,4'-diaminodiphenyl)amine, N-methyl(2,2'-diaminodiphenyl)amine, N-methyl(2,3'-diaminodiphenyl)amine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'- Diaminobenzophenone, 1,4-diaminonaphthalene, 2,2'-diaminobenzophenone, 2,3'-diaminobenzophenone, 1,5-diamino Naphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7 -diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(3-aminophenyl)ethane, 1,3 - bis(4-aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,4- (3-aminophenyl)butane, bis(3,5-diethyl-4-aminophenyl)methane, 1,4-bis(4-aminophenoxy)benzene, 1,3- Bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 1,4-bis(4- Aminobenzyl)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-[1,4-phenylenebis(methylene)]diphenylamine, 4,4' -[1,3-phenylenebis(methylene)]diphenylamine, 3,4'-[1,4-phenylenebis(methylene)]diphenylamine, 3,4'-[1, 3-phenylphenylbis(methylene)]diphenylamine, 3,3'-[1,4-phenylenebis(methylene)]diphenylamine, 3,3'-[1,3-phenylene Bis(methylene)]diphenylamine, 1,4-phenylene bis[(4-aminophenyl)methanone], 1,4-phenylene bis[(3-aminophenyl)methyl Ketone], 1,3-phenylene bis[(4-aminophenyl)methanone], 1,3-phenylene bis[(3-aminophenyl)methanone], 1,4-stretch Phenyl bis(4-aminobenzoate), 1,4-phenylene bis(3-aminobenzoate), 1,3-phenylene bis(4-aminobenzoate) ), 1,3-phenylene bis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalic acid Acid ester, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate, N,N'-(1,4-phenylene) double (4-Aminobenzoguanamine), N,N'-(1,3-phenylene)bis(4-aminophenylguanamine), N,N'-(1,4-phenylene) double (3-aminophenylguanamine), N,N'-bis(1,3-phenylene)bis(3-aminophenylguanamine), N,N'-bis(4-aminophenyl) Paraxylamine, N,N'-bis(3-aminophenyl)terephthalamide, N,N'-bis(4-aminophenyl)m-xylyleneamine, N , N'-bis(3-aminophenyl)m-xylyleneamine, 9,10-bis(4-aminophenyl)anthracene, 4,4'-bis(4-aminophenoxy) Diphenylanthracene, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexa Fluoropropane, 2,2'-bis(4-aminophenyl) Fluoropropane, 2,2'-bis(3-aminophenyl)hexafluoropropane, 2,2'-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2'-double (4-Aminophenyl)propane, 2,2'-bis(3-aminophenyl)propane, 2,2'-bis(3-amino-4-methylphenyl)propane, 1,3 - bis(4-aminophenoxy)propane, 1,3-bis(3-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,4- Bis(3-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,5-bis(3-aminophenoxy)pentane, 1,6 - bis(4-aminophenoxy)hexane, 1,6-bis(3-aminophenoxy)hexane, 1,7-bis(4-aminophenoxy)heptane, 1, 7-double (3- Aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3-aminophenoxy)octane, 1,9-bis (4) -aminophenoxy)decane, 1,9-bis(3-aminophenoxy)decane, 1,10-(4-aminophenoxy)decane, 1,10-(3- Aminophenoxy)decane, 1,11-(4-aminophenoxy)undecane, 1,11-(3-aminophenoxy)undecane, 1,12-(4- Aminophenoxy)dodecane, 1,12-(3-aminophenoxy)dodecane, 4-(aminomethyl)aniline, 3-(aminomethyl)aniline, 3-( Aromatic diamines such as (aminomethyl)methyl)aniline, 4-(2-aminoethyl)aniline, 3-(2-aminoethylaniline), bis(4-aminocyclohexyl) An alicyclic diamine such as methane or bis(4-amino-3-methylcyclohexyl)methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diamine Pentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminodecane, 1,10-diamine An aliphatic diamine such as decane, 1,11-diaminoundecane or 1,12-diaminododecane.

Further, other examples of the diamine component represented by the above formula [1-A] include, for example, an alkyl group, a fluorine-containing alkyl group, an aromatic ring, an aliphatic ring or a heterocyclic ring in the side chain of the diamine, or have such a A large ring-shaped substitute composed of the like. Specifically, for example, there is a diamine compound represented by the following formula [DA1] to formula [DA30].

In the above formula [DA1]~form [DA6], A ₂ represents -COO-, -OCO-, -CONH-, -NHCO-, -CH ₂ -, -O-, -CO- or -NH-, A ₃ represents a linear or branched alkyl group having 1 to 22 carbon atoms or a linear or branched fluorine-containing alkyl group having 1 to 22 carbon atoms.

In the formula [DA7], p is an integer of 1 to 10.

In the formula [DA8] to [DA12], A ₄ represents an alkyl group having 2 to 24 carbon atoms or a fluorine-containing alkyl group.

In the formula [DA13] and the formula [DA15], A ₅ represents -O-, -OCH ₂ -, -CH ₂ O-, -COOCH ₂ -, or -CH ₂ OCO-, and the A ₆ system represents a carbon number of 1~. 22 alkyl, alkoxy, fluoroalkoxy or fluoroalkoxy.

In the formula [DA16]~[DA18], A ₇ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ - or -CH ₂ -, A ₈ represents an alkyl group having 1 to 22 carbon atoms, an alkoxy group, a fluorine-containing alkoxy group or a fluorine-containing alkoxy group.

In the formula [DA19] and the formula [DA20], A ₉ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ -, -CH ₂ -, -O-, or -NH-, A ₁₀ represents a fluorine group, a cyano group, a trifluoromethyl group, a nitro group, an azo group, a methyl group, an ethyl group, an ethylene group Base, or hydroxyl group.

In the formula [DA21] and the formula [DA22], A ₁₁ represents an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomers of 1,4-cyclohexene are each a trans isomer.

In the formula [DA23] and the formula [DA24], A ₁₂ represents an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomers of 1,4-cyclohexene are each a trans isomer.

Specific examples of the tetracarboxylic acid represented by the above formula [1-B] include 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 2,3. ,4,5-tetrahydrofuran tetracarboxylate Acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3,4-dicarboxy-1-cyclohexyl succinic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1 An alicyclic tetracarboxylic acid such as naphthylsuccinic acid.

Other examples of tetracarboxylic acids, such as pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalene tetra Carboxylic acid, 2,3,6,7-nonanetetracarboxylic acid, 1,2,5,6-nonanetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3 ',4-biphenyltetracarboxylic acid, bis(3,4-dicarboxyphenyl)ether, 3,3',4,4'-benzophenonetetracarboxylic acid, bis(3,4-dicarboxybenzene Base, bis(3,4-dicarboxyphenyl)methane, 2,2-bis(3,4-dicarboxyphenyl)propane, 1,1,1,3,3,3-hexafluoro-2 , 2-bis(3,4-dicarboxyphenyl)propane, bis(3,4-dicarboxyphenyl)dimethyl decane, bis(3,4-dicarboxyphenyl)diphenyl decane, 2, 3,4,5-pyridinetetracarboxylic acid, 2,6-bis(3,4-dicarboxyphenyl)pyridine, 3,3',4,4'-diphenylphosphonium tetracarboxylic acid, 3,4, 9,10-perylene dianhydride such as tetracarboxylic acid or 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid.

The polyimine precursor used in the method for producing a liquid crystal alignment film of the present invention contains a repeating unit represented by the above formula [1] and a repeating unit selected from the following formula [2] and the following formula [3] ] indicates at least one of the repeating units. The repeating unit represented by the following formula [2] and formula [3] has a photoreactive group. Therefore, the polyimide precursor used in the method for producing a liquid crystal alignment film of the present invention becomes a photoreactive group. The photoreactive group is preferably a group which generates a crosslinking reaction by light irradiation.

The polyimine precursor used in the method for producing a liquid crystal alignment film of the present invention contains at least one selected from the group consisting of the following formulas [2] and [3].

In the above formula [2], R ₅ represents a divalent organic group constituting a photoreactive group. R ₆ represents a tetravalent organic group. R ₇ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms. R ₈ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms. The n ₂ system represents a positive integer.

In the above formula [3], R ₉ represents a divalent organic group. R ₁₀ represents a divalent organic group constituting a photoreactive group. The n ₃ system represents a positive integer.

The repeating unit represented by the above formula [2] can be obtained by using a diamine component represented by the following formula [2-A] and a tetracarboxylic dianhydride component of an acid anhydride of a tetracarboxylic acid represented by the following formula [2-B]. .

In the above formula [2-A] and formula [2-B], R ₅ and R ₆ are the same as R ₅ and R ₆ in the above formula [2].

A photocrosslinkable diamine can be used for the diamine component represented by the above formula [2-A]. Specific examples thereof include the compounds shown below.

The tetracarboxylic acid represented by the above formula [2-B] has, for example, the same tetracarboxylic acid as those exemplified for the tetracarboxylic acid represented by the above formula [1-B].

The repeating unit represented by the above formula [3] can be obtained by using a diamine component represented by the following formula [3-A] and a dicarboxylic acid component represented by the following formula [3-B].

In the above formula [3-A] and formula [3-B], R ₉ and R ₁₀ are the same as R ₉ and R ₁₀ in the above formula [3].

The diamine component represented by the above formula [3-A] has, for example, the above formula [1- A] represents the same diamine component as the diamine component.

Specific examples of the dicarboxylic acid component represented by the above formula [3-B] include the compounds shown below.

The pre-polyimine used in the method for producing a liquid crystal alignment film of the present invention The content ratio of the repeating unit represented by the above formula [2] and/or the repeating unit represented by the above formula [3] with respect to the repeating unit represented by the above formula [1] is as follows.

When only the repeating unit represented by the above formula [2] is contained, the molar ratio (the repeating unit represented by the formula [1]) / (the repeating unit represented by the formula [2]) is preferably 1/99 to 99/ The range of 1 is more preferably in the range of 5/95 to 95/5.

Similarly, when only the repeating unit represented by the above formula [3] is contained, the molar ratio (the repeating unit represented by the formula [1]) / (the repeating unit represented by the formula [3]) is preferably 1/99. The range of ~99/1 is more preferably in the range of 5/95 to 95/5.

In addition, when both the repeating unit represented by the above formula [2] and the repeating unit represented by the above formula [3] are included, the molar ratio is expressed in (the repeating unit represented by the formula [1]) / {(form [2] The repeating unit expressed by + (the repeating unit represented by the formula [3])} is preferably in the range of 1/99 to 99/1, more preferably in the range of 5/95 to 95/5.

In the present invention, the polyimine precursor having the photoreactive group may be a polycondensation reaction obtained by subjecting a diamine component containing a novel diamine represented by the following formula (4) to a tetracarboxylic dianhydride. A quinone imine precursor.

X ¹ , X ² , X ³ , X ⁴ and X ⁵ in the formula (4) are as defined above. In the formula (4), one or more cinnamoyl groups are contained. Further, in the formula (4), the cinnamyl group is represented by the following formula, and the diamine represented by the formula (4) has at least one, preferably 2 to 4, cinnamyl groups.

Further, in the formula (4), the position of the amine group (-NH ₂ ) which the benzene ring has is not particularly limited, but from the viewpoint of liquid crystal alignment performance or ease of synthesis, for example, each is relative to -X ¹ -X ² - X ³ -X ⁴ -X ⁵ -, preferably present in the para or meta position.

Preferred diamines represented by the formula (4) include, for example, the following diamines.

(wherein X represents independently a bond of a single bond, an ether (-O-), an ester (-COO- or -OCO-) or a guanamine (-CONH- or -NHCO-), and the Y system independently represents a single A bond or an alkyl group having a carbon number of 1 to 5, and the Z series independently represents an alkyl group having a carbon number of 1 to 10 or a phenyl group. In each formula, the bonding position of the amine group on the benzene ring or the benzene relative to the center The position of the bond group of the ring is not particularly limited.)

Specific examples of the diamine represented by the formula (4) include the following diamines.

Liquid crystal alignment treatment using a polyamidiamine precursor such as polyacrylamide or polyglycolate containing a diamine of the present invention represented by the above formula (4), polyimine, polyamine or the like The liquid crystal alignment film formed by the agent reduces a change in the alignment property of the liquid crystal caused by AC (alternating current) driving, for example, a change in the alignment direction of the liquid crystal. Therefore, the liquid crystal display element having the liquid crystal alignment film is based on the liquid crystal alignment property of the liquid crystal alignment film driven by AC. Therefore, it is difficult to generate an afterimage by AC driving, and the afterimage characteristic by AC driving is very good. Further, by using the liquid crystal alignment film formed of the diamine represented by the above formula (4), it is possible to form an excellent liquid crystal alignment property and substantially no alignment defect.

Thus, the liquid crystal alignment film obtained by using the diamine represented by the above formula (4) and the liquid crystal display element having the liquid crystal alignment film can reduce variations in liquid crystal alignment performance caused by AC driving, and are less likely to be generated by the AC driving device. Although the reason for the residual image is not clear, it can be presumed as follows. For example, in the main chain of a polyimine precursor, a polyimine, a polyimine, or the like, a specific photoreactive group derived from a diamine represented by the formula (4) can be imparted to the liquid crystal by introduction ( That is, -HN-C ₆ H ₄ -X ¹ -X ² -X ³ -X ⁴ -X ⁵ -C ₆ H ₄ -NH-), even if the liquid crystal moves due to AC driving, it is derived from the formula (4) The specific photoreactive group of the amine is not easily moved, so the alignment orientation is not easily deviated.

Further, a structure (specific photoreactive group) derived from the diamine represented by the formula (4) of the present invention is introduced into a side chain instead of a polyimine imide, a polyimine, a polyimine, or the like. In the main chain, the liquid crystal moved by the AC drive is squeezed to move the side chain, and the movement of the side chain is shifted, and the structure of the diamine represented by the formula (4) from the alignment imparting liquid crystal is moved, so that the alignment direction is large. Offset, easy to produce afterimages.

The method for synthesizing the diamine represented by the formula (4) is not particularly limited, and can be produced, for example, according to a synthesis example described later. When the diamine represented by the above formula (a) is used, it can be synthesized by the method shown below.

The diamine represented by the formula (a) will correspond to the following formula (a') The dinitro compound is synthesized, and then the nitro group is reduced in a solvent to be converted into an amine group. The method for reducing the dinitro compound is not particularly limited, and is usually carried out using palladium-carbon, platinum oxide, Raney nickel, iron, tin chloride, platinum black, ruthenium-alumina, platinum sulfide carbon or the like as a catalyst. Further, from the viewpoint that the olefin does not carry out the ring element, the chemical reduction method using iron or tin chloride can be used from the viewpoint of selectively reducing the nitro group in a high yield. The reduction is carried out by using a solvent such as ethyl acetate, toluene, tetrahydrofuran, dioxane or an alcohol as a solvent, and reduction using hydrogen, a hydrazine, hydrogen chloride, ammonium chloride or the like as a reducing agent.

(wherein X and Y are synonymous with X and Y in formula (a), respectively)

The method for synthesizing the dinitro compound represented by the formula (a') is not particularly limited, and the synthesis can be carried out by any method. Specific examples thereof include synthesis by a method represented by the following reaction formula.

In the above reaction, a method of reacting a nitrobenzene compound A with a compound B having a carboxylic acid, for example, in an organic solvent, for example, a direct condensation method using DMAP/DCC or DMAP/EDC, and a thiocyanate using a carboxylic acid A method in which chlorine, oxalyl chloride, phosphoryl chloride, sulfuryl chloride, phosphorus trichloride or the like is used as an acid chloride to carry out a reaction. Further, DMAP means 4-N,N-dimethylaminopyridine, DCC means dicyclohexylcarbodiimide (CARBODIIMIDE), and EDC means 1-(3-dimethylaminopropyl)-3. - Ethyl carbodiimide hydrochloride.

In the above nitrobenzene compound A, X and Y are respectively synonymous with X and Y in the formula (a), and specific examples thereof include 4-nitrophenol, 3-nitrophenol, 2-nitrophenol, and 4-nitro group. Benzyl alcohol, 3-nitrobenzyl alcohol, 2-nitrobenzyl alcohol, 4-nitrophenylethanol, 3-nitrophenylethyl, 2-nitrophenylethyl and the like. If necessary, a linking group Y can be inserted between the benzene ring and the hydroxyl group. Further, another substituent may be bonded to the benzene ring, and the substitution position of the nitro group on the benzene ring may be appropriately selected to obtain the substitution position of the desired diamine. Moreover, the compound shown here is an example, and is not specifically limited.

The organic solvent is a solvent which does not affect the reaction, and specifically, for example, an aromatic solvent such as toluene or xylene; an aliphatic hydrocarbon solvent such as hexane or heptane; dichloromethane or 1,2-dichloroethane; a halogen solvent such as an alkane; an ether solvent such as tetrahydrofuran or 1,4-dioxane; N,N-dimethylformamide; N,N-dimethylacetamide; N-methylpyrrolidone; The aprotic polar solvent such as dimethyl hydrazine may be used singly or in combination. The usage amount of these is arbitrary.

The other diamine is also the same as the diamine represented by the above formula (a). Synthesize by synthesis.

The polyimine precursor such as polyglycolic acid or polyglycolate of the present invention is obtained by reacting a diamine component containing a diamine represented by the above formula (4) with a tetracarboxylic acid component. . Further, the polyglycolate can also be obtained by a method in which a carboxyl group of polyproline is converted into an ester. Further, the polyamidene precursors such as polylysine and polylysine are subjected to ruthenium imidization to obtain the polyimine of the present invention.

The polyamine of the present invention is a reaction of a diamine component containing a diamine represented by the above formula (4) with a halide of a dicarboxylic acid in the presence of a base, or a diamine represented by the above formula (1) The diamine component is obtained by reacting a dicarboxylic acid in the presence of a suitable condensing agent or a base.

Any of a polyimine precursor such as polyamine or a polyamidite, a polyimine, and a polyamine can be used as a polymer for obtaining a liquid crystal alignment film. In addition, the diamine component represented by the formula (4) may be one type or two or more types, and the diamine component may contain one type or two or more types of diamine represented by the formula (4). Other diamines than others.

The content of the diamine represented by the formula (4) is 10 mol% or more, preferably 30 to 100 mol%, more preferably 50 to 100 mol%, based on the total amount of the diamine component.

In the present specification, the ratio is based on the number of moles unless otherwise specified.

The diamine component may contain a diamine other than the diamine represented by the above formula (4), and a diamine exemplified as a specific example of the diamine component represented by the above formula [1-A] may be used.

The above-mentioned other diamines may be used in combination of one type or two types or more in combination with the liquid crystal alignment property, the voltage holding ratio, and the charge accumulated in the liquid crystal alignment film.

The tetracarboxylic acid component means at least one selected from the group consisting of a tetracarboxylic acid and a tetracarboxylic acid derivative. Examples of the tetracarboxylic acid derivative include a tetracarboxylic acid dihalide, a tetracarboxylic dianhydride, a tetracarboxylic acid diester dichloride, and a tetracarboxylic acid diester.

For example, a polycarboxylic acid can be obtained by reacting a tetracarboxylic acid dihalide or a tetracarboxylic dianhydride with a diamine component. Further, a reaction of a tetracarboxylic acid diester dichloride with a diamine component or a reaction of a tetracarboxylic acid diester with a diamine component in the presence of a suitable condensing agent or a base can provide a polyphthalate. The tetracarboxylic acid component to be used may be one type or two or more types.

The tetracarboxylic acid component is, for example, a tetracarboxylic dianhydride represented by the following formula (5).

(In the formula (5), Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms of a non-aromatic cyclic hydrocarbon group having 4 to 8 carbon atoms)

In the formula (5), specific examples of Z ₁ include, for example, a tetravalent organic group represented by the following formulas (5a) to (5j).

(In the formula (5a), Z ₂ to Z ₅ represent a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, and each may be the same or different. In the formula (5g), Z ₆ and Z ₇ represent a hydrogen atom or a group. Base, each can be the same or different.)

A particularly preferable structure of Z ₁ , from the viewpoint of polymerization reactivity or ease of synthesis, is preferably a formula (5a), a formula (5c), a formula (5d), a formula (5e), a formula (5f) or a formula (5g). . Among them, the formula (5a), the formula (5e), the formula (5f) or the formula (5g) is preferred.

In addition, the ratio of the tetracarboxylic dianhydride to the total amount of the tetracarboxylic acid component represented by the formula (5) is not particularly limited, and for example, the tetracarboxylic acid component may be only the tetracarboxylic dianhydride represented by the above formula (5). Of course, the tetracarboxylic acid component may contain a tetracarboxylic acid or a tetracarboxylic acid derivative other than the tetracarboxylic dianhydride represented by the formula (5) within a range that does not impair the effects of the present invention. In this case, the tetracarboxylic acid dianhydride represented by the above formula (5) is more preferably 1 mol% or more of the total amount of the tetracarboxylic acid component, more preferably 5 mol% or more, and still more preferably 10 mol% or more.

The tetracarboxylic dianhydride other than the tetracarboxylic dianhydride represented by the above formula (5), for example, the tetracarboxylic dianhydride exemplified as another example of the tetracarboxylic acid represented by the above formula [1-B] can be used. .

The tetracarboxylic acid diester is also not particularly limited. Specifically, it is as follows.

Specific examples of the aliphatic tetracarboxylic acid diester are 1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid. Dialkyl acid ester, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid dialkyl ester, 1,2,3,4-tetramethyl-1,2,3,4 - cyclobutane tetracarboxylic acid dialkyl ester, 1,2,3,4-cyclopentane tetracarboxylic acid dialkyl ester, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dialkyl ester, 1,2,4 , 5-cyclohexanetetracarboxylic acid dialkyl ester, 3,4-dicarboxy-1-cyclohexyl succinic acid dialkyl ester, 3,4-dicarboxy-1,2,3,4-tetrahydro-1- Dialkyl naphthalene succinate, dialkyl 1,2,3,4-butane tetracarboxylate, dicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic acid dialkyl ester, 3,3',4,4'-dicyclohexyltetracarboxylic acid dialkyl ester, 2,3,5-tricarboxycyclopentyl acetic acid dialkyl ester, cis-3,7-dibutylcyclooctane-1, 5-diene-1,2,5,6-tetracarboxylic acid dialkyl ester, tricyclo[4.2.1.0 ^2,5 ]decane-3,4,7,8-tetracarboxylic acid-3,4:7 , 8-dialkyl ester, hexacyclo[6.6.0.1 ^2,7 .0 ^3,6 .1 ^9,14 .0 ^10,13 ]hexadecane-4,5,11,12-tetracarboxylic acid-4, 5:11,12-dialkyl ester, 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid dialkyl ester, etc. .

The aromatic tetracarboxylic acid dialkyl esters are, for example, dialkyl pyromellitate, dialkyl 3,3',4,4'-biphenyltetracarboxylate, 2,2',3,3'-biphenyl tetra Dialkyl carboxylate, dialkyl 2,3,3',4-biphenyltetracarboxylate, dialkyl 3,3',4,4'-benzophenone tetracarboxylate, 2,3,3 ',4-Dibenzophenone tetracarboxylic acid dialkyl ester, bis(3,4-dicarboxyphenyl)ether dialkyl ester, bis(3,4-dicarboxyphenyl)decane dialkyl ester, 1,2 , 5,6-naphthalenetetracarboxylic acid dialkyl ester, 2,3,6,7-naphthalenetetracarboxylic acid dialkyl ester, and the like.

In order to obtain the polyamine of the present invention, the dicarboxylic acid or the like which reacts with the diamine component is not particularly limited. In order to obtain polyamine, a specific example of an aliphatic dicarboxylic acid of a dicarboxylic acid or a derivative thereof which reacts with a diamine component is propylene. Acid, oxalic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, muconic acid, 2-methyladipate, trimethyl adipate, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethyl succinic acid, sebacic acid, sebacic acid, suberic acid and the like.

An alicyclic dicarboxylic acid such as 1,1-cyclopropanedicarboxylic acid, 1,2-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutane II Carboxylic acid, 1,3-cyclobutanedicarboxylic acid, 3,4-diphenyl-1,2-cyclobutanedicarboxylic acid, 2,4-diphenyl-1,3-cyclobutanedicarboxylate Acid, 1-cyclobutene-1,2-dicarboxylic acid, 1-cyclobutene-3,4-dicarboxylic acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylate Acid, 1,3-cyclopentanedicarboxylic acid, 1,1-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4- Cyclohexanedicarboxylic acid, 1,4-(2-northene)dicarboxylic acid, norbornene-2,3-dicarboxylic acid, bicyclo[2.2.2]octane-1,4-dicarboxylic acid Bicyclo[2.2.2]octane-2,3-dicarboxylic acid, 2,5-dioxo-1,4-bicyclo[2.2.2]octanedicarboxylic acid, 1,3-adamantane dicarboxylate Acid, 4,8-dioxo-1,3-adamantane dicarboxylic acid, 2,6-spiro[3.3]heptane dicarboxylic acid, 1,3-adamantane dicarboxylic acid, camphoric acid, and the like.

The aromatic dicarboxylic acid is, for example, o-phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tert-butylisophthalic acid, 5-aminoisophthalic acid Formic acid, 5-hydroxyisophthalic acid, 2,5-dimethylterephthalic acid, tetramethylterephthalic acid, 1,4-naphthalene dicarboxylic acid, 2,5-naphthalene dicarboxylic acid, 2, 6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-anthraquinone dicarboxylic acid, 1,4-nonanedicarboxylic acid, 2,5-biphenyldicarboxylic acid, 4,4'- Biphenyldicarboxylic acid, 1,5-biphenyldicarboxylic acid, 4,4"-biphenyldicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 4,4'-diphenyl Ethane dicarboxylic acid, 4,4'-diphenylpropane dicarboxylic acid, 4,4'- Diphenylhexafluoropropanedicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-bibenzyldicarboxylic acid, 4,4'-stilbene dicarboxylic acid, 4,4 '-Diphenylacetylene (tolan) dicarboxylic acid, 4,4'-carbonyldibenzoic acid, 4,4'-sulfonyldibenzoic acid, 4,4'-dithiodibenzoic acid, p-phenylene Acetic acid, 3,3'-p-phenyl dipropionic acid, 4-carboxycinnamic acid, p-benzene diacrylic acid, 3,3'-[4,4'-(methylenebis-p-phenylene)] Dipropionic acid, 4,4'-[4,4'-(oxadi-p-phenylene)]dipropionic acid, 4,4'-[4,4'-(oxydi-p-phenylene)] Dicarboxylic acid such as dibutyric acid, (isopropylidene di-p-phenylenedioxy)dibutyric acid or bis(p-carboxyphenyl)dimethyloxane.

The dicarboxylic acid containing a heterocyclic ring, for example, 1,5-(9-oxoindole)dicarboxylic acid, 3,4-furandicarboxylic acid, 4,5-thiazoledicarboxylic acid, 2-phenyl-4, 5-thiazoledicarboxylic acid, 1,2,5-thiazole-3,4-dicarboxylic acid, 1,2,5-oxadiazole-3,4-dicarboxylic acid, 2,3-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2,5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, 3,5-pyridinedicarboxylic acid, and the like.

The above various dicarboxylic acids may be those having an acid dihalide or an acid anhydride. These dicarboxylic acids, particularly dicarboxylic acids which provide a linear polyamine, are preferred from the viewpoint of maintaining the alignment of liquid crystal molecules. Among these, it is preferred to use terephthalic acid, isoterephthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenylmethane. Dicarboxylic acid, 4,4'-diphenylethane dicarboxylic acid, 4,4'-diphenylpropane dicarboxylic acid, 4,4'-diphenylhexafluoropropane dicarboxylic acid, 2,2- Bis(phenyl)propane dicarboxylic acid, 4,4"-terphenyl (terphenyl) dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,5-pyridinedicarboxylic acid, such acid dihalides The above compounds may also have an isomer, but may be a mixture containing them. It is also possible to use two or more kinds of compounds in combination. The dicarboxylic acid to be used is not limited to the above-exemplified compounds.

The tetracarboxylic dianhydride, the other tetracarboxylic acid, the tetracarboxylic acid derivative, the dicarboxylic acid, etc., which are represented by the above formula (5), are required to blend liquid crystal alignment, voltage holding ratio, charge charge, etc. when used as a liquid crystal alignment film. The characteristics can be used in one type or in a mixture of two or more types.

The reaction of the diamine component with the tetracarboxylic acid component is usually carried out in an organic solvent. The organic solvent to be used in this case is not particularly limited as long as it is a polyimine precursor which can dissolve the produced polyamic acid or the like. Specific examples are N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, dimethyl alum, and four Methyl urea, pyridine, dimethyl hydrazine, hexamethyl hydrazine, γ-butyrolactone, isopropanol, methoxymethylpentanol, dipentene, ethyl amyl ketone, methyl decyl ketone , methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cellosolve, ethyl celecoxib, methyl sarbuta acetate, ethyl 赛路苏Acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate , propylene glycol monomethyl ether, propylene glycol tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, Dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetic acid Ester, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol , diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, dibutyl ether, diisobutyl ketone, methyl cyclohexene, propyl ether, dihexyl ether, dioxane, Hexane, N-Pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, acetone Methyl ester, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3 -methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone Wait. These may be used alone or in combination. Further, even a solvent which does not dissolve the polyimide precursor can be used in combination with the above solvent as long as it does not precipitate the polyamic acid after the formation. Further, since the water in the organic solvent hinders the polymerization reaction and causes hydrolysis of the produced polyimide precursor, the organic solvent is preferably dried by dehydration.

When the diamine component and the tetracarboxylic acid component are reacted in an organic solvent, the following method may be employed: a solution in which the diamine component is dispersed or dissolved in an organic solvent is stirred, and the tetracarboxylic acid component is directly added or dispersed or dissolved in an organic solvent. In the middle, the method of adding, for example, a method in which a diamine component is added to a solution in which a tetracarboxylic acid component is dispersed or dissolved in an organic solvent, a method in which a tetracarboxylic acid component and a diamine component are alternately added, and the like, and the like Any of these methods can be used. When a plurality of kinds of compounds are used as the diamine component or the tetracarboxylic acid component, the reaction may be carried out in a state of being mixed beforehand, or may be sequentially reacted, or a low molecular weight body after each reaction may be subjected to a mixing reaction. The polymerization temperature at this time may be selected from any temperature of from -20 ° C to 150 ° C, preferably from -5 ° C to 100 ° C. Further, the reaction can be carried out at any concentration. However, when the concentration is too low, it is difficult to obtain a high molecular weight polyimine precursor (especially poly Amine), and when the concentration is too high, the viscosity of the reaction liquid is too high to be uniformly stirred. Therefore, the concentration of the total amount of the diamine component and the tetracarboxylic acid component is preferably from 1 to 50% by mass, more preferably from 5 to 30% by mass, based on the reaction liquid. The initial stage of the reaction is carried out at a high concentration, and thereafter an organic solvent can be added.

In the polycondensation reaction of the polyimine precursor such as polyamine, the ratio of the molar number of the synthetic mole of the diamine component to the total number of moles of the tetracarboxylic acid component is preferably 0.8 to 1.2. As with the usual polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weight of the resulting polyimine precursor.

Further, the polyglycolate may be subjected to a reaction of a tetracarboxylic acid diester dichloride and a diamine component or a tetracarboxylic acid diester and a diamine component in the presence of a suitable condensing agent or a base as described above. Obtained by reaction. Further, polylysine is synthesized in advance by the above method, and a carboxyl group of polylysine is esterified by a polymer reaction.

Specifically, for example, the tetracarboxylic acid diester dichloride and the diamine component are reacted in the presence of a base and an organic solvent at -20 to 150 ° C, preferably 0 to 50 ° C, for 30 minutes to 24 hours, preferably. For 1 to 4 hours, a polyphthalate can be synthesized.

As the base, pyridine, triethylamine, 4-methylaminopyridine or the like can be used, and for the reaction to proceed stably, pyridine is preferred. The amount of the base to be added is preferably from 2 to 4 moles per mole of the tetracarboxylic acid diester dichloride from the viewpoint of easy removal amount and easy availability of a high molecular weight body.

Further, when the tetracarboxylic acid diester and the diamine component are subjected to polycondensation in the presence of a condensing agent, triphenyl phosphite, dicyclohexylcarbodiimide or 1-ethyl- can be used as the condensing agent. 3-(3-dimethylaminopropyl)carbodiimide hydrochloride, N,N'-carbonyldiimidazole, dimethoxy-1,3,5-three Azinyl methylmorpholine, O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium tetrafluoroborate (Tetramethyluronium‧tetrafluoroborate:), O -(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium hexafluorophosphate, (2,3-dihydro-2-thioxo-3-benzene And dizozolyl)sulfonic acid diphenyl ester, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)4-methoxymorpholine chloride n-hydrate, etc. .

Further, in the method using the above condensing agent, a Lewis acid is added as an additive, and the reaction can be carried out efficiently. The Lewis acid is preferably a lithium halide such as lithium chloride or lithium bromide. The amount of the Lewis acid added is preferably 0.1 to 1.0 times the molar amount relative to the diamine or tetracarboxylic acid diester of the reaction.

The solvent for the above reaction may be the same solvent as the solvent used in the synthesis of the polyamic acid, but from the viewpoint of the solubility of the monomer and the polymer, N-methyl-2-pyrrolidone and γ-butane are preferred. The ester may be used alone or in combination of two or more. The concentration at the time of the synthesis is not easily precipitated from the polymer, and a high molecular weight body is easily obtained, and a reaction solution of a tetracarboxylic acid derivative such as a tetracarboxylic acid diester dichloride or a tetracarboxylic acid diester and a diamine component is contained. The total concentration is preferably from 1 to 30% by mass, more preferably from 5 to 20% by mass. Further, in order to prevent hydrolysis of the tetracarboxylic acid diester dichloride, it is preferred to carry out dehydration as much as possible for the synthesis of the polyphthalate, and it is preferred to prevent the external air from being mixed by reaction in a nitrogen atmosphere.

The polyimine precursor thus polymerized is, for example, a polymer having a repeating unit represented by the following formula [h].

(In the formula [h], R ₁₁ is a tetravalent organic group derived from a tetracarboxylic acid component of a raw material, R ₁₂ is a divalent organic group derived from a diamine component of a raw material, and A ₁₁ and an A ₁₂ hydrogen atom or a carbon number of 1 ~4 alkyl groups, each of which may be the same or different, and j is a positive integer.)

In the formula [h], R ₁₁ and R ₁₂ each may be a single type, and have the same repeating unit of the polymer, or R ₁₁ or R ₁₂ may be a plurality of polymers each having a repeating unit of a different structure.

In the formula [h], R ₁₁ is a group derived from a tetracarboxylic acid component represented by the following formula [k] or the like from a raw material. Further, R ₁₂ is a group derived from a diamine component represented by the following formula [s] or the like from a raw material. For example, when R ₁₂ is a group derived from the diamine represented by the above formula (4), it is -C ₆ H _{4 .} -X ¹ -X ² -X ³ -X ⁴ -X ⁵ -C ₆ H ₄ -. Further, the above formula [h] is a diamine represented by the above formula (4) as a raw material, and is introduced into -HN-C ₆ H ₄ -X ¹ -X ² -X ³ -X ⁴ -X ⁵ -C in the main chain. ₆ H ₄ -NH-polyimine precursor.

(In the formula [k] and the formula [s], R ₁₁ and R ₁₂ are the same as those defined by the formula [h].)

The polyimine is obtained by subjecting the polyimine precursor of the formula [h] to dehydration ring closure.

A method for subjecting a polyimine precursor to ruthenium imidization, for example, a hydrazine imidization by directly heating a solution of a polyimide precursor solution, or a contact of a catalyst in a solution of a polyimide precursor solution Media imidization and the like.

The temperature at which the polyimine precursor is thermally imidated in the solution is from 100 ° C to 400 ° C, preferably from 120 ° C to 250 ° C, and the water formed by the imidization reaction is excluded from the reaction system. It is preferred to carry out the oxime imidization reaction.

The catalyst oxime imidization of the polyimide precursor is added to the polyimide precursor solution by adding a basic catalyst and an acid anhydride, and stirring at -20 to 250 ° C, preferably 0 to 180 ° C.醯imination. The amount of the alkaline catalyst is 0.5 to 30 moles, preferably 2 to 20 moles, of the prolyl group, and the amount of the acid anhydride is 1 to 50 moles of the amidate group, preferably 3 to 3 30 times Mo.

The basic catalyst is, for example, pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine or the like. Among them, pyridine is preferred because it has a moderate basicity required for carrying out the reaction.

Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. When acetic anhydride is used, purification after the completion of the reaction is easy, which is preferable. The imidization ratio of the imidization by the catalyst oxime can be controlled by adjusting the amount of the catalyst, the reaction temperature, and the reaction time.

When the polyimine precursor or the polyimine is recovered from a reaction solution of a polyamidiamine precursor such as polyglycolic acid or a polyphthalamide, or a polyimine, the reaction solution is injected into the solvent. It can be precipitated in the middle. Used for precipitation The solvent may, for example, be methanol, acetone, hexane, butyl sarbuta, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, water or the like. The polyimine precursor or the polyimine which is deposited in a solvent and precipitated is collected by filtration, and then dried at normal temperature or under heat at normal pressure or reduced pressure. Further, the precipitated polyimine precursor or polyimine is redissolved in an organic solvent, and the reprecipitation recovery operation is repeated 2 to 10 times to reduce the polyimine precursor or polyimine. Impurities. In this case, the solvent is, for example, an alcohol, a ketone or a hydrocarbon. When three or more solvents selected from the above are used, the purification efficiency can be further improved, which is preferable.

The dehydration ring closure ratio (the imidization ratio) of the amidino group of the polyimine is not necessarily required to be 100%, and may be arbitrarily selected in the range of 0 to 100%, preferably 50 to 100%.

Polyamide can also be synthesized in the same manner as polyglycolate.

The molecular weight of the polymer film (liquid crystal alignment film) obtained by using the above-mentioned polymer film (liquid crystal alignment film), the workability and polymerization at the time of formation of a polymer film, and the molecular weight of the polymerized polyimide precursor, the polyimine, and the polyamine. When the uniformity of the coating film is used, the weight average molecular weight measured by GPC (Gel Permeation Chromatography) is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

In the method for producing a liquid crystal alignment film of the present invention, a film containing the polyimide precursor is formed on a substrate, followed by heating, and the polarized ultraviolet light is irradiated to the film surface while maintaining the heating state. By the polarized ultraviolet irradiation, a photocrosslinking reaction of higher reaction efficiency is initiated, an anisotropy is poured into a film containing a polyimide precursor, and a polyfluorene is formed on the substrate. A liquid crystal alignment film of an amine precursor.

The present invention is preferably one which does not contain a polyimine in a film containing a polyimide precursor. If it is unavoidable to contain polyimine in the film containing the polyimide precursor, the content thereof is preferably 30 mol% or less, more preferably 20 mol%, relative to the polyimide precursor. Hereinafter, it is more preferably 10 mol% or less.

When the polyimine is a relatively rigid polymer material and contains a large amount of the film, the flexibility of the film containing the polyimide precursor is affected. Further, when polarized light is irradiated, the effect of heat treatment is affected, and the light reaction in the film containing the polyimide precursor may be hindered. As a result, the photoreaction has a concern that the anisotropy is prevented from being introduced into the film containing the polyimide precursor.

Therefore, the heating temperature of the film containing the polyimide precursor formed on the substrate is a temperature at which the high light reaction efficiency of the film is achieved, and is preferably a temperature range in which the chemical reaction of the polyimide precursor is not generated. In other words, the upper limit of the heating temperature is selected to cause a thermal reaction depending on the type of the polyimide precursor to be used, and the temperature which does not become a range of the polyimine is preferable. The lower limit is preferably a temperature at which the effect of improving the photoreactivity described later is selected depending on the type of the polyimide precursor to be used.

Specifically, the film containing the polyimide precursor formed on the substrate has a heating temperature of 50 to 300 ° C, preferably 80 to 250 ° C, more preferably 150 to 200 ° C.

The heating of the film containing the polyimide precursor on the substrate and the maintenance of the heating state thereof can be maintained using, for example, a hot plate, a heat cycle type oven, or an IR (infrared) type oven. Among them, the choice to use can be easily carried out UV The heating plate for wire irradiation is preferred.

When the film surface of the film containing the polyimide precursor is irradiated with polarized ultraviolet rays, the substrate is irradiated with ultraviolet rays polarized by the polarizing plate in a fixed direction. For the wavelength of the ultraviolet light to be used, for example, ultraviolet rays in the range of 100 to 400 nm can be used. It is preferred to select the optimum wavelength depending on the type of the polyimide precursor to be used, such as a filter. For example, the use of ultraviolet light in the range of 300 to 400 nm can selectively initiate photocrosslinking reaction. Ultraviolet rays can use, for example, light emitted by a high pressure mercury lamp.

The method for producing a liquid crystal alignment film of the present invention can carry out a photoreaction of a film containing a polyimide precursor using a very high efficiency. Specifically, compared with the conventional photo-alignment method, the photoreaction in the film containing the polyimine precursor constituting the liquid crystal alignment film can be increased by about 10 times with an ultraviolet irradiation amount of about 1/10. The efficiency of the light reaction.

As a result, in the alignment treatment by the irradiation light of the present invention, the amount of ultraviolet rays irradiated can be much smaller than that of the conventional photoalignment method. In other words, in the present invention, a liquid crystal alignment film having alignment control energy of liquid crystal can be produced with a smaller amount of ultraviolet rays than the number of J to tens of J necessary for the conventional photoalignment method. Specifically, it is a liquid crystal alignment film which is an ultraviolet irradiation amount in the range of 10 to 1000 mJ, preferably 20 to 800 mJ. At this time, ultraviolet light having a strength of 10 to 20 mW is irradiated for several seconds to several tens of seconds, and a liquid crystal alignment film can be produced, and the production capacity (processing ability) of the liquid crystal alignment film can be improved.

As described above, in the method for producing a liquid crystal alignment film of the present invention, the film containing the polyimide precursor is heated, and while maintaining the heated state, the polarized ultraviolet rays are irradiated, and the amount of ultraviolet irradiation is small, so that the film can be efficiently produced. Create a liquid crystal alignment film. In other words, the present invention can produce a liquid crystal alignment film with high efficiency.

Moreover, the liquid crystal display element is manufactured using the obtained liquid crystal alignment film by the manufacturing method of the liquid crystal alignment film of this invention.

Next, a liquid crystal display element using the liquid crystal alignment film of the present invention will be described.

The liquid crystal alignment treatment agent of the present invention contains the above-mentioned polyimine precursor such as polylysine or polylysine, polyimine or polyamine. The liquid crystal alignment treatment agent refers to a solution for forming a liquid crystal alignment film, and a solution in which a polymer component for forming a liquid crystal alignment film is dispersed or dissolved in an organic solvent. Here, the liquid crystal alignment film refers to a film for aligning the liquid crystal in a predetermined direction.

The present invention contains at least one selected from the group consisting of a polyimine precursor such as polylysine or polylysine of the present invention, a polyimine, and a polyamine as the polymer component.

Further, the polyimine precursor of the present invention is dissolved in a solvent to form a liquid liquid crystal alignment treatment agent, and can also be used for forming a film containing a polyimide precursor, and can also be used for a liquid crystal alignment film. Manufacturing. In this case, the content of the polyimide precursor in the liquid crystal alignment agent is preferably from 0.1 to 30% by mass, more preferably from 0.5 to 30% by mass, particularly preferably from 1 to 25% by mass.

In the liquid crystal alignment treatment agent of the present invention, all of the polymer components contained in the present invention may be the polyimine imine precursors such as polylysine or polylysine of the present invention, polyimine, polyamine, and the like. Alternatively, another polymer may be blended in the polymer component of the polyimine precursor such as polylysine or polyperurate of the present invention, polyimine or polyamine. When the polymer component is other polymer, the content of other polymers in the total amount of the polymer component It is 0.5 to 50% by mass, preferably 1 to 30% by mass.

The other polymer, for example, a diamine component which is reacted with, for example, a tetracarboxylic dianhydride component, a dicarboxylic acid or the like, is a polyimine precursor obtained by using only a diamine other than the diamine represented by the above formula (4) of the present invention. , polyimine, polyamine, and the like. Further, examples of the polymer other than the polyimine precursor, the polyimine, and the polyamine include, for example, an acrylic polymer, a methacrylic polymer, and polystyrene.

In the liquid crystal alignment treatment agent of the present invention, at least one selected from the group consisting of a polyamidamine precursor such as polylysine or polylysine of the present invention, a polyimine, and a polyamine is mixed as necessary. The total content of the other polymers is 0.1 to 30% by mass, preferably 1 to 25% by mass, more preferably 3 to 15% by mass, particularly preferably 3 to 10% by mass, based on the total amount of the polymer component.

The organic solvent used in the liquid crystal alignment treatment agent of the present invention is not particularly limited as long as it is an organic solvent which dissolves the polymer component of the polyimine precursor of the present invention, polyimine or polyamine. Specific examples thereof are N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N- Ethylpyrrolidone, N-vinylpyrrolidone, dimethyl hydrazine, tetramethylurea, pyridine, dimethyl hydrazine, hexamethylarylene, γ-butyrolactone, 3-methoxy-N,N- Dimethylpropanamide, 3-ethoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, 1,3-dimethyl-imidazole Linone, ethyl amyl ketone, methyl decyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, ethylene carbonate, propylene carbonate, diethylene glycol Diglyme, 4-hydroxy-4-methyl-2-pentanone, and the like. These can be used separately Or mixed use.

The liquid crystal alignment agent of the present invention may contain an organic solvent (also referred to as a weak solvent) which improves the film thickness uniformity or surface smoothness of the polymer film when the liquid crystal alignment agent is applied, within a range that does not impair the effects of the present invention. Or a compound. A compound or the like which improves the adhesion between the liquid crystal alignment film and the substrate may be contained.

Specific examples of the weak solvent for increasing the film thickness uniformity or the surface smoothness include, for example, isopropanol, methoxymethylpentanol, methyl stilbene, ethyl stilbene, and butyl 赛苏苏. , Methyl sulphate acetate, ethyl sirolimus acetate, butyl carbitol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetic acid Ester, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol Alcohol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, Dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, B Isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, dibutyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, Two Ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, 3- Methyl ethyl ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, 3-methoxy Butyl propyl propionate, 1-methyl Oxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diethyl Acid ester, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy)propanol, lactate An organic solvent having a low surface tension such as an ester, ethyl lactate, n-propyl lactate, n-butyl lactate or isoamyl lactate.

These weak solvents can be used one kind or a mixture of plural kinds. When the weak solvent as described above is used, it is preferably from 5 to 80% by mass, more preferably from 20 to 60% by mass, based on the total of the organic solvent contained in the liquid crystal alignment agent.

Examples of the compound which improves the uniformity of the film thickness or the surface smoothness include a fluorine-based surfactant, a rhodium-based surfactant, and a nonionic surfactant. More specifically, for example, EF TOP EF301, EF303, EF352 (manufactured by TOHKEM PRODUCTS), MAGAFAC F171, F173, R-30 (manufactured by Dainippon Ink Co., Ltd.), FLORARD FC430, FC431 (manufactured by Sumitomo 3M), Asahigard AG710 , SURFLON S-382, SC101, SC102, SC103, SC104, SC105, SC106 (made by Asahi Glass Co., Ltd.). The ratio of use of the surfactant is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass, per 100 parts by mass of the polymer component contained in the liquid crystal alignment treatment agent.

The compound which improves the adhesiveness of a liquid crystal alignment film and a board|substrate, for example, has a functional decane compound, and an epoxy-containing compound. For example, 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, 2-aminopropyltriethoxydecane, N- (2-Aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)- 3-aminopropylmethyldimethoxydecane, 3-ureidopropyltrimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyl Trimethoxydecane, N-ethoxycarbonyl-3-aminopropyltriethoxydecane, N-triethoxydecylpropyltriethylamine, N-trimethoxydecylpropyl Tri-extension ethyltriamine, 10-trimethoxydecyl-1,4,7-triazadecane, 10-triethoxydecyl-1,4,7-triazadecane, 9- Trimethoxydecyl-3,6-diazaindolyl acetate, 9-triethoxydecyl-3,6-diazaindolyl acetate, N-benzyl-3-amino group Propyltrimethoxydecane, N-benzyl-3-aminopropyltriethoxydecane, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyl Triethoxy decane, N-bis(oxyethyl)-3-aminopropyltrimethoxydecane, N-bis(oxyethyl)-3-aminopropyltriethoxydecane, Ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl Oleic ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2 , 4-hexanediol, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane Alkane, N, N, N', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and the like.

When the compound is used to improve the adhesion to the substrate, the amount thereof is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal alignment agent. When the amount used is less than 0.1 part by mass, the effect of improving the adhesion cannot be expected, and when it is more than 30 parts by mass, the liquid crystal alignment may be deteriorated.

In addition to the above, the liquid crystal alignment agent of the present invention may be added with a dielectric or a conductive material in order to change the dielectric properties such as the dielectric constant or the conductivity of the liquid crystal alignment film, without departing from the effects of the present invention. The hardness or tightness of the film in the case of the liquid crystal alignment film is a crosslinkable compound for the purpose.

The liquid crystal alignment treatment agent of the present invention is applied onto a substrate, and after firing, if necessary, it is subjected to alignment treatment by rubbing treatment or light irradiation (radiation irradiation), and can be used as a liquid crystal alignment film. The liquid crystal alignment film of the present invention is formed by using a diamine represented by the above formula (4) as a raw material of a polyimide precursor, a polyimine, a polyamide, or the like, and thus is not easily caused by AC driving. Variety.

The substrate is not particularly limited as long as it is a substrate having high transparency, and a plastic substrate such as an acrylic substrate or a polycarbonate substrate can be used in addition to the glass substrate. From the viewpoint of process simplification, it is preferred to use a substrate on which an ITO (Indium Tin Oxide) electrode or the like for liquid crystal driving is formed. Further, when the reflective liquid crystal display element is only a single-sided substrate, an opaque substrate such as a germanium wafer may be used. In this case, a material that reflects light such as aluminum may be used as the electrode. Further, as a high-function element of a TFT-type liquid crystal display element, an element such as a transistor formed between an electrode for driving a liquid crystal and a substrate can be used.

The coating method of the liquid crystal alignment agent is not particularly limited, but industrially, it is generally applied by a method such as screen printing, lithography, soft printing, or inkjet printing. Other coating methods include, for example, a dipping method, a roll coating method, a slit coating method, a spin coating method, a spray method, and the like, and such coating methods may be used depending on the purpose.

After coating the liquid crystal alignment treatment agent on the substrate, the heating plate and the heat are used A heating means such as a ring type oven or an IR (infrared) type oven may evaporate the solvent at 50 to 300 ° C, preferably 80 to 250 ° C to form a liquid crystal alignment film (film of a polymer). When the thickness of the liquid crystal alignment film after baking is too thick, it is disadvantageous in terms of power consumption of the liquid crystal display element. When the thickness is too thin, the reliability of the liquid crystal display element may be lowered. Therefore, it is preferably 5 to 300 nm, more preferably 10 ~100nm. When the liquid crystal is aligned horizontally or obliquely, the liquid crystal alignment film after baking is treated by rubbing or polarized ultraviolet light irradiation to align the liquid crystal. For example, by diffracting a photoreactive group derived from a diamine represented by the formula (4) by light irradiation such as polarized ultraviolet rays, the liquid crystal can be aligned by the anisotropy generated by the reaction.

The irradiation of the polarized ultraviolet rays allows the liquid crystal alignment film to be irradiated while being heated.

The film containing the polyimide precursor formed on the substrate is heated at 80 to 250 ° C using, for example, a hot plate. At this time, the upper limit of the heating temperature is selected to generate a thermal reaction depending on the type of the polyimide precursor to be used, and does not become a temperature in the range of the polyimide. The lower limit is a temperature at which the effect of improving the photoreactivity is selected depending on the type of the polyimide precursor to be used.

Heating is performed at a selected temperature within the above range, and the film surface of the film containing the polyimide precursor is irradiated with polarized ultraviolet rays in a predetermined direction in a predetermined direction as described above. In this way, a liquid crystal alignment film having liquid crystal alignment control energy on the substrate can be manufactured.

In the liquid crystal display device of the present invention, a liquid crystal alignment cell is obtained by a conventional method from the liquid crystal alignment treatment agent of the present invention, and a liquid crystal cell is produced by a known method to form a liquid crystal display device. For example, a liquid crystal display element having a liquid crystal cell in which the liquid crystal cell has two substrates arranged in opposite directions A liquid crystal layer disposed between the substrate and the substrate, and the liquid crystal alignment film formed between the substrate and the liquid crystal layer by the liquid crystal alignment treatment agent of the present invention. Such a liquid crystal display element of the present invention has, for example, an IPS (In-Plane Switching) method, a TN (Twisted Nematic) method, an OCB (Optically Compensated Bend) or a vertical alignment (VA: Vertical Alignment). ) Ways, etc. The liquid crystal alignment film system may be provided in at least one of the two substrates.

The substrate used for the liquid crystal display device of the present invention is not particularly limited as long as it is a substrate having high transparency, and a substrate for driving a transparent electrode for liquid crystal is usually formed on the substrate. Specific examples are the same as those described for the liquid crystal alignment film.

In the liquid crystal alignment film, the liquid crystal alignment treatment agent of the present invention is applied onto the substrate, and then fired, if necessary, by rubbing treatment or irradiation with radiation such as polarized ultraviolet rays, as described above.

The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited, and a positive type liquid crystal having positive dielectric anisotropy, a negative type liquid crystal having negative dielectric anisotropy, or the like can be used. As a specific example, a liquid crystal material used in the conventional horizontal alignment method, for example, MLC-2041 manufactured by MercK Co., Ltd., or the like can be used.

For example, in the production of a liquid crystal cell, for example, a pair of substrates of a liquid crystal alignment film are prepared, and a spacer such as a bead is spread on a liquid crystal alignment film of one of the substrates, so that the liquid crystal alignment film surface becomes inside, and then Combining another substrate, injecting liquid crystal under reduced pressure, or encapsulating the liquid crystal, dropping the liquid crystal onto the liquid crystal alignment film surface on which the spacer is dispersed, bonding the substrate and performing the bonding The method of packaging, etc. The thickness of the spacer is preferably from 1 to 30 μm, more preferably from 2 to 10 μm. In the case of the liquid crystal display element of the horizontal alignment type, the polarizing plate is disposed outside the substrate after the liquid crystal is sealed as described above.

As described above, the liquid crystal display element produced by using the liquid crystal alignment treatment agent of the present invention has a liquid crystal alignment film capable of suppressing a change in liquid crystal alignment performance due to AC driving, and therefore has excellent afterimage characteristics, is less likely to cause scorch, and is less likely to be generated. Poor display or contrast reduction.

[Examples]

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

[Example A] <Synthesis Example 1 (Synthesis of Monomer (3))>

Monomer (3) is synthesized according to reaction formula (i).

20 g (0.09 mol) of the monomer (1) was added to 60 ml of dry ethanol, and the mixture was stirred and refluxed to dissolve all the solids, followed by stirring under reflux for 2 hours. After the completion of the reaction, ethanol was distilled off under reduced pressure until the solid was slightly precipitated. The reaction solution of about 50% of the dried ethanol is cooled at room temperature, and the precipitate is separated by filtration, and then washed with ethanol to obtain a single substance of interest. Body (2). The solvent of the filtrate was distilled off under reduced pressure to give a mixture of the desired substance isomer. The mixture of the isomers was recrystallized from ethyl acetate to give the monomer (2). The yield was 10 g and the yield was 35.2%.

The ¹ H-NMR of the obtained monomer (2) is based on TMS (Si(CH ₃ ) ₄ ), and an NMR measuring device is used in a solvent of deuterium dimethyl hydrazine (DMSO). (made by JEOL, 500MHz). The results of ¹ H-NMR measurement of the monomer (2) are shown below, and the same applies to the other compounds.

¹ H-NMR (500 MHz, DMSO, δ ppm) = 1.27 (t, J = 7.09 Hz, 6H, -CH ₂ -CH ₃ -), 4.28 (q, J = 7.04 Hz, 4H, -CH ₂ -CH ₃ ) , 7.96 (S, 2H, Ph).

A small amount of N,N'-dimethylformamide was added to a mixture of 4.77 g (0.015 mol) of monomer (2) and 35 ml of ethyl acetate. Next, 3 ml of Thionyl Chloride was added, and the mixture was stirred and refluxed. After confirming that all the solids were dissolved, the mixture was further stirred under reflux for 1 hour. After the completion of the reaction, the solvent and excess sulphur sulfoxide were distilled off under reduced pressure. The resulting product was purified by recrystallization from hexane to give purified monomer (3). The yield was 4.3 g and the yield was 80.5%. The solvent of ¹ H-NMR was deuterated chloroform (CDCl ₃ ).

¹ H-NMR (500 MHz, CDCl ₃ , δ ppm) = 1.43 (t,J = 7.12 Hz, 6H, -CH ₂ -CH ₃ -), 4.46 (q, J = 7.1 Hz, 4H, -CH ₂ -CH ₃ ), 8.16 (S, 2H, Ph).

<Synthesis Example 2 (synthesis of monomer (5))>

Monomer (5) is synthesized according to reaction formula (ii).

A small amount of N,N'-dimethylformamide was added to a mixture of 4.8 g (0.022 mol) of monomer (4) and 50 ml of ethyl acetate. Next, 6 ml of Thionyl Chloride was added, and the mixture was stirred and refluxed. After confirming that all the solids were dissolved, the mixture was further stirred under reflux for 1 hour. After the completion of the reaction, the solvent and excess sulphur sulfoxide were distilled off under reduced pressure. The product was purified by recrystallization from ethyl acetate/hexane to give purified monomer (5). The yield was 3.5 g and the yield was 62.4%. The solvent of ¹ H-NMR was deuterated chloroform (CDCl ₃ ).

¹ H-NMR (500 MHz, CDCl ₃ , δ ppm) = 6.72 (d, J = 15.7 Hz, 2H, -CH=CH-), 7.65 (S, 4H, Ph), 7.82 (d, J = 15.7 Hz, 2H) , -CH=CH-)

(molecular weight determination)

The measurement of the molecular weight of the polyphthalate derivative is carried out in the same manner as the method for measuring the molecular weight of the polymer described in [Example B] to be described later.

<Synthesis Example 3 (synthesis of 6FPAE2-8)>

APHFP 1.49 g (4.5 mmol) and LiCl 1.5 g were added to 60 ml of dry NMP, and stirred at room temperature until the solids were all dissolved. Then, 0.12 g of chlorotrimethylnonane was added. A mixed solution of 0.31 g (0.9 mmol) of monomer (3), 0.91 g (3.5 mmol) of monomer (5), and 5 ml of dry THF was added dropwise to the solution at room temperature, and the funnel was dropped to 2 ml of dryness. After washing with dry THF, it was stirred for 1 hour. Then, the reaction temperature was gradually raised, and the mixture was further stirred at 40 ° C for 3 hours. After the completion of the reaction, the reaction solution was poured into 800 ml of water, and the resulting polymer was separated, filtered, and washed with ethanol and acetone. Next, the polymer was dried, dissolved in NMP, and reprecipitated by ethanol and chloroform to carry out purification. Then, the precipitate was separated by filtration and sufficiently dried to obtain a polyamine derivative (6FPAE2-8) powder (A) having a Mn of 31,400 and a Mw of 66,000.

<Synthesis Example 4 (synthesis of 6FPAE5-5)>

APHFP 1.49 g (4.5 mmol) and LiCl 1.5 g were added to 60 ml of dry NMP, and stirred at room temperature until the solids were all dissolved. Then, 0.12 g of chlorotrimethylnonane was added. A mixed solution of 0.77 g (2.2 mmol) of monomer (3), 0.57 g (2.2 mmol) of monomer (5), and 5 ml of dry THF was added dropwise to the solution at room temperature, and the funnel was washed with 2 ml of dry THF. Stir for 1 hour. Then, the reaction temperature was gradually raised, and the mixture was further stirred at 40 ° C for 3 hours. After the completion of the reaction, the reaction solution was poured into 800 ml of water, and the resulting polymer was separated, filtered, and washed with ethanol and acetone. Next, the polymer was dried, dissolved in NMP, and reprecipitated by ethanol and chloroform to carry out purification. Then, the precipitate was separated by filtration and sufficiently dried to obtain a polyamine derivative (6FPAE5-5) powder (B) having a Mn of 28,600 and a Mw of 52,800.

<Example 1>

The polyphthalate derivative (6FPAE2-8) powder obtained in Synthesis Example 3 NMP and BCS were added to the final (A), and the mixture was diluted to 4% by mass to obtain a liquid crystal alignment treatment agent (I). No abnormality such as turbidity or precipitation was observed in the liquid crystal alignment treatment agent, and it was confirmed that the resin component was uniformly dissolved.

<Example 2>

NMP and BCS were added to the polyacetate derivative (6FPAE5-5) powder (B) obtained in Synthesis Example 4, and diluted to 4% by mass to obtain a liquid crystal alignment treatment agent (II). No abnormality such as turbidity or precipitation was observed in the liquid crystal alignment treatment agent, and it was confirmed that the resin component was uniformly dissolved.

<Example 3>

The liquid crystal alignment treatment agent (I) containing the polyphthalate derivative (6FPAE2-8) obtained in Example 1 was spin-coated on a transparent glass substrate (thickness: 1.1 mm, width: 30 mm, length: 40 mm). After drying on a hot plate at 80 ° C for 5 minutes, a coating film having a film thickness of 40 nm was formed, and a substrate to which a liquid crystal alignment film before treatment was attached was obtained.

<Example 4>

The liquid crystal alignment treatment agent (II) containing the polyphthalate derivative (6FPAE5-5) obtained in Example 2 was spin-coated on a transparent glass substrate and dried on a hot plate at 80 ° C for 5 minutes. A coating film having a film thickness of 40 nm was formed, and a substrate to which a liquid crystal alignment film before treatment was attached was obtained.

<Example 5>

Using the substrate obtained in Example 3 and attached to the liquid crystal alignment film before the treatment, the substrate was heated to 240 ° C on the hot plate, and in the heated state, the liquid crystal alignment film surface on the substrate was polarized by a certain direction. A plate (manufactured by Mejiro Precision Co., Ltd.) was irradiated with ultraviolet light after polarized light (high-pressure mercury lamp manufactured by Oxtail Electric Co., Ltd., and polarized light irradiation device manufactured by Mejiro Precision Co., Ltd.). The intensity of the ultraviolet light after the polarized light was 14 mW at a wavelength of 365 nm, and the ultraviolet irradiation amount was 500 mJ. Thus, a substrate to which the liquid crystal alignment film after the treatment was attached was obtained.

<Comparative Example 1>

Using the substrate obtained in the third embodiment and attached to the liquid crystal alignment film before the treatment, the liquid crystal alignment film surface on the substrate was irradiated with a polarized light in a predetermined direction with respect to the liquid crystal alignment film surface on the substrate, and the polarized ultraviolet light was irradiated. The intensity of the ultraviolet light after the polarized light was 14 mW at a wavelength of 365 nm, and the ultraviolet irradiation amount was 500 mJ. Thus, a substrate on which a liquid crystal alignment film of a liquid crystal alignment film is formed is obtained.

<Comparative Example 2>

Using the substrate obtained in the third embodiment and attached to the liquid crystal alignment film before the treatment, the liquid crystal alignment film surface on the substrate was irradiated with a polarized light in a predetermined direction with respect to the liquid crystal alignment film surface on the substrate, and the polarized ultraviolet light was irradiated. The intensity of the ultraviolet light after the polarized light was 14 mW at a wavelength of 365 nm, and the ultraviolet irradiation amount was 4500 mJ. Thus, a substrate on which a liquid crystal alignment film of a liquid crystal alignment film is formed is obtained.

<Example 6>

Using the substrate obtained in Example 4 and attached to the liquid crystal alignment film before the treatment, the substrate was heated to 160 ° C on the hot plate, and in the heated state, the liquid crystal alignment film surface on the substrate was polarized by a certain direction. The plate is irradiated with ultraviolet light after polarized light. The intensity of the ultraviolet light after the polarized light was 14 mW at a wavelength of 365 nm, and the ultraviolet irradiation amount was 250 mJ. Thus, a substrate to which the liquid crystal alignment film after the treatment was attached was obtained.

<Example 7>

A substrate to which a liquid crystal alignment film to be treated was attached was obtained in the same manner as in Example 6 except that the heating temperature on the hot plate was 200 °C.

<Example 8>

A substrate to which a liquid crystal alignment film to be treated was attached was obtained in the same manner as in Example 6 except that the heating temperature on the hot plate was 240 °C.

The production conditions of the substrates with liquid crystal alignment films obtained in Examples 3 to 8, Comparative Example 1, and Comparative Example 2 are shown in Table 1.

<Example 9>

The liquid crystal alignment agent A5 (described in [Example B] described later) was spin-coated on a quartz substrate (thickness: 1.1 mm, width: 40 mm, length: 40 mm). Subsequently, the film was dried on a hot plate at 90 ° C for 60 seconds, and then fired in a hot air circulating oven at 200 ° C for 30 minutes to form a liquid crystal alignment film having a film thickness of 100 nm. Next, the substrate was heated to 240 ° C on a hot plate, and in the heated state, the liquid crystal alignment film surface on the substrate was placed on a polarizing plate, and ultraviolet rays of 313 nm were irradiated at 1000 mJ/cm ² to obtain a substrate with a liquid crystal alignment film.

<Comparative Example 3>

A liquid crystal alignment film was formed in the same manner as in Example 9. At room temperature (23 ° C), the liquid crystal alignment film surface of the substrate was placed on a polarizing plate, and ultraviolet rays of 313 nm were irradiated at 1000 mJ/cm ² to obtain a substrate with a liquid crystal alignment film.

<Comparative Example 4>

A liquid crystal alignment film was formed in the same manner as in Example 9 to obtain unheated and ultraviolet light. The substrate of the liquid crystal alignment film attached to the line. The ultraviolet absorption spectrum of Comparative Example 4 was used as a comparison object of Example 9 and Comparative Example 3.

The production conditions of the substrate with the liquid crystal alignment film obtained in Example 9 and Comparative Examples 3 and 4 are shown in Table 2.

[Evaluation of Liquid Crystal Alignment Film 1] (Method for measuring ultraviolet absorption spectrum)

The measurement of the ultraviolet absorption spectrum of the liquid crystal alignment film was carried out by UV-Vis absorption height measurement.

The ultraviolet absorption spectrum of the liquid crystal alignment film was measured using the substrate obtained in Example 5 and attached to the treated liquid crystal alignment film. Further, the ultraviolet absorption spectrum of the liquid crystal alignment film before the alignment treatment was measured using the substrate obtained in the third embodiment and attached to the liquid crystal alignment film before the treatment.

Fig. 1 is a view showing the ultraviolet absorption spectrum of the liquid crystal alignment film before the alignment treatment obtained in Example 3 and the liquid crystal alignment film obtained in Example 5.

Fig. 1 is a view showing an ultraviolet absorption spectrum of a liquid crystal alignment film obtained in Example 5, and the object of comparison was an ultraviolet absorption spectrum of a liquid crystal alignment film of Example 3 which was not heated or irradiated with polarized ultraviolet rays. As shown in Fig. 1, the ultraviolet absorption spectrum ("Example 5" in Fig. 1) of the liquid crystal alignment film of Example 5 and the ultraviolet absorption spectrum of the liquid crystal alignment film of Example 3 (in Fig. 1) When "Comparative Example 3" was described, it was found that the liquid crystal alignment film of Example 5 had a large decrease in absorbance at a wavelength of around 350 nm. This decrease in absorbance is caused by the heating of 240 ° C on the hot plate and the irradiation of 500 mJ of polarized ultraviolet light. The absorption of the liquid crystal alignment film of Example 3 at a wavelength of about 300 to 350 nm is derived from the absorption of the photoreactive group contained in the polyphthalate derivative constituting the liquid crystal alignment film by heating at 240 ° C on a hot plate. The irradiation treatment of polarized ultraviolet rays of 500 mJ revealed that the photocrosslinking reaction was efficiently carried out in the film of the polyphthalate derivative.

Next, the substrate on which the liquid crystal alignment film of the liquid crystal alignment film of Comparative Example 1 was formed and the substrate on which the liquid crystal alignment film of the liquid crystal alignment film of Comparative Example 2 were formed were used, and the ultraviolet absorption spectrum of each liquid crystal alignment film was measured. Further, the ultraviolet absorption spectrum of the liquid crystal alignment film before the alignment treatment was measured using the substrate obtained in the third embodiment and attached to the liquid crystal alignment film before the treatment.

2 is an ultraviolet absorption spectrum of the liquid crystal alignment film before the alignment treatment obtained in Example 3 and the liquid crystal alignment films obtained in Comparative Examples 1 and 2.

2 is an ultraviolet absorption spectrum of the liquid crystal alignment film of Comparative Example 1 and the liquid crystal alignment film of Comparative Example 2, and the comparison object is an ultraviolet absorption spectrum of the liquid crystal alignment film of Example 3 which is not heated or irradiated with polarized ultraviolet rays. As shown in Fig. 2, the ultraviolet absorption spectrum of the liquid crystal alignment film of Example 3 ("Example 3" shown in Fig. 2) and the ultraviolet absorption spectrum of the liquid crystal alignment film of Comparative Example 1 are shown in Fig. 2 (Comparative Example 1) When the comparison was made, it was found that the absorbance at a wavelength of 300 to 350 nm was lowered in the liquid crystal alignment film of Comparative Example 1. Similarly, the ultraviolet absorbing light of the liquid crystal alignment film of Comparative Example 2 was used. When the spectrum ("Comparative Example 2" described in Fig. 2) was compared, it was found that the absorbance at a wavelength of 300 to 350 nm was further lowered in the liquid crystal alignment film of Comparative Example 2. From this, it is understood that as the amount of irradiation of the polarized ultraviolet rays increases, the absorbance of the liquid crystal alignment film at a wavelength of around 300 to 350 nm decreases. The absorption near the wavelength of 300 to 350 nm is derived from the absorption of the photoreactive group contained in the polyphthalate derivative constituting the liquid crystal alignment film, and the film of the polyphthalate derivative is known by irradiation treatment with polarized ultraviolet rays. In the middle, a photocrosslinking reaction is carried out.

Further, when comparing FIG. 1 with FIG. 2, it is found that the liquid crystal alignment film of Comparative Example 2 shown in FIG. 2 has an absorbance at a wavelength of about 300 to 350 nm and the liquid crystal alignment film obtained in Example 5 shown in FIG. The absorbance at around 350 nm is equivalent. The amount of the polarized ultraviolet ray irradiated in Example 5 was 500 mJ, and the amount of the polarized ultraviolet ray in the liquid crystal alignment film of Comparative Example 2 was 4500 mJ. From this, it was found that the liquid crystal alignment film of Example 5 which was subjected to heat treatment at 240 ° C during the irradiation of the polarized ultraviolet light was subjected to photoreaction with a very high efficiency. In the case of the liquid crystal alignment film of Example 5, the efficiency of photoreaction was 10 times higher than that of Comparative Examples 1 and 2, which was equal to the case where the liquid crystal alignment film which was not subjected to heat treatment at the time of polarized light irradiation was used.

3 is an ultraviolet absorption spectrum of a liquid crystal alignment film obtained in Example 9 of the present invention, and the object of comparison is Comparative Example 3 in which polarized ultraviolet light is irradiated at room temperature, and liquid crystal alignment film of Comparative Example 4 which is not heated or not subjected to polarized ultraviolet light. UV absorption spectrum. As shown in FIG. 3, the ultraviolet absorption spectrum of the liquid crystal alignment film of Example 9 ("Example 9" shown in FIG. 3) and the ultraviolet absorption spectrum of the liquid crystal alignment film of Comparative Example 3 are shown in FIG. When comparing, it is known that the liquid crystal alignment film of Example 9 is at a wavelength. The absorbance near 310 nm is greatly reduced. This decrease in absorbance is caused by the heating of 240 ° C on the hot plate and the irradiation of 1000 mJ of polarized ultraviolet light. The liquid crystal alignment film of Example 9 has an absorption in the vicinity of a wavelength of 300 nm to 350 nm due to absorption of a photoreactive group contained in a polyamic acid derivative constituting the liquid crystal alignment film, by heating at 240 ° C on a hot plate. The irradiation treatment of polarized ultraviolet rays of 1000 mJ revealed that the film of the polyproline derivative was subjected to photocrosslinking reaction with high efficiency. In the case of polarized ultraviolet light irradiation, the liquid crystal alignment film of Example 9 which was heat-treated at 240 ° C was used for photoreaction with very high efficiency.

[Evaluation of Liquid Crystal Alignment Film 2]

The ultraviolet absorption spectrum of the liquid crystal alignment film was measured using the substrate obtained in Example 6 and attached to the treated liquid crystal alignment film. Further, the ultraviolet absorption spectrum was measured using the substrate obtained in the fourth embodiment and attached to the liquid crystal alignment film before the treatment as a comparison object. In the ultraviolet absorption spectrum of the liquid crystal alignment film obtained in Example 4, the absorption maximum at a wavelength of about 350 nm in the ultraviolet absorption spectrum of the liquid crystal alignment film was 1.0, and the absorption in the ultraviolet absorption spectrum of the liquid crystal alignment film of Example 6 at a wavelength of about 350 nm was 0.76. It was found that the liquid crystal alignment film of Example 6 had a large decrease in absorbance at a wavelength of around 350 nm. From the results, it was found that the liquid crystal alignment film of Example 6 which was heat-treated at 160 ° C during the irradiation of the polarized ultraviolet rays was subjected to photoreaction with high efficiency.

In the same manner, the ultraviolet absorption spectrum of the liquid crystal alignment film was measured using the substrates obtained in the examples 7 and 8 attached to the liquid crystal alignment film after the treatment, and the absorption absorbance at a wavelength of around 350 nm was evaluated to be 0.70. More realistic In the liquid crystal alignment film of Example 6, the degree of decrease in the absorbance at the maximum absorption was slightly large, and the liquid crystal alignment film of Example 7 was equivalent to the degree of decrease in the absorbance of the liquid crystal alignment film of Example 8.

From the above evaluation results, when the polarized ultraviolet ray is irradiated onto the liquid crystal alignment film and the heat treatment is performed at 160 ° C, the effect of improving the photoreaction efficiency is sufficient, and even at a heating temperature of 200 ° C or higher, the photoreaction efficiency is high. The lifting effect is almost the same as in the case of 160 °C. In other words, the heating temperature at the time of the polarized ultraviolet ray irradiation in the alignment treatment of the liquid crystal alignment film can suppress the change of the polyamidomate derivative constituting the liquid crystal alignment film to the polyimine, and is particularly preferably 160 to 200 °C.

<Example 10>

A liquid crystal alignment film was produced using the liquid crystal alignment treatment agent (I) obtained in Example 1, and a liquid crystal cell using the liquid crystal alignment film was produced. The liquid crystal cell corresponds to the characteristics of the liquid crystal alignment film to form a liquid crystal cell which is aligned in parallel. The obtained liquid crystal cell is held by a pair of polarizing plates to constitute a liquid crystal display element.

In the method of producing a liquid crystal cell, the liquid crystal alignment treatment agent (I) is spin-coated on a glass substrate (length 30 mm × width 40 mm, thickness 1, 1 mm) with an ITO electrode, and dried on a hot plate at 80 ° C for 5 minutes. A liquid crystal alignment film was formed in the form of a coating film having a film thickness of 40 nm, and a substrate to which a liquid crystal alignment film before treatment was attached was obtained. It is understood that the liquid crystal alignment film formed on the substrate is excellent in uniformity of film thickness, and the liquid crystal alignment treatment agent (I) exhibits excellent coatability.

Using the obtained substrate attached to the liquid crystal alignment film before the treatment, The plate is heated to 240 ° C on a hot plate, and the liquid crystal alignment film surface on the substrate is irradiated with polarized ultraviolet rays in a predetermined direction with respect to the liquid crystal alignment film surface on the substrate. The intensity of the ultraviolet light after the polarized light was 14 mW at a wavelength of 365 nm, and the ultraviolet irradiation amount was 250 mJ. Thus, a substrate to which the liquid crystal alignment film after the treatment was attached was obtained.

Two sheets of the substrate with the liquid crystal alignment film were prepared, and a 14 μm spacer (manufactured by Nippon Shokubai Co., Ltd., a real ball) was spread on one of the liquid crystal alignment film surfaces, and then the sealant was applied thereon (Mitsui Chemical Co., Ltd.) System XN-1500T). Next, after the other substrate was bonded to the liquid crystal alignment film in a face-to-face manner, the sealant was heated at 150 ° C for 150 minutes to harden the empty cell. This empty cell was injected into nematic liquid crystal (ZLI-4792 manufactured by Merck Co., Ltd.) at 105 ° C or higher at a temperature equal to or higher than the liquid crystal phase by a capillary phenomenon to obtain a liquid crystal cell.

<Example 11>

A liquid crystal cell was produced in the same manner as in Example 10 except that the amount of ultraviolet light irradiated by the polarized light was set to 500 mJ.

<Comparative Example 5>

A liquid crystal cell was produced in the same manner as in Example 10 except that the amount of ultraviolet light irradiated by the polarized light was set to 50 mJ.

<Comparative Example 6>

A liquid crystal alignment film was produced using the liquid crystal alignment treatment agent (I) obtained in Example 1, and a liquid crystal cell using the liquid crystal alignment film was produced. Liquid crystal cell system and implementation Example 10 was also prepared as a liquid crystal cell in parallel alignment.

In the method of producing a liquid crystal cell, a liquid crystal alignment treatment agent (I) is spin-coated on a glass substrate with an ITO electrode, and dried on a hot plate at 80 ° C for 5 minutes, and then a liquid crystal alignment is formed in the form of a coating film having a film thickness of 40 nm. The film was obtained by attaching a substrate to the liquid crystal alignment film before the treatment.

Using the obtained substrate attached to the liquid crystal alignment film before the treatment, the liquid crystal alignment film surface on the substrate is irradiated with polarized ultraviolet rays in a predetermined direction with respect to the liquid crystal alignment film surface on the substrate. The intensity of the ultraviolet light after the polarized light was 14 mW at a wavelength of 365 nm, and the ultraviolet irradiation amount was 50 mJ. Thus, a substrate to which the liquid crystal alignment film after the treatment was attached was obtained.

Two sheets of the liquid crystal alignment film were prepared, and a 14 μm spacer was sprinkled on one of the liquid crystal alignment film faces, and then the sealant was applied thereon. Next, after bonding the other substrate to the liquid crystal alignment film, the sealant was heated at 150 ° C for 150 minutes to harden the empty cell. This empty cell was injected into nematic liquid crystal (ZLI-4792 manufactured by Merck Co., Ltd.) at 105 ° C or higher at a temperature equal to or higher than the liquid crystal phase by a capillary phenomenon to obtain a liquid crystal cell.

<Comparative Example 7>

A liquid crystal cell was produced in the same manner as in Comparative Example 10 except that the amount of irradiation of ultraviolet rays after the polarizing was set to 250 mJ.

<Comparative Example 8>

The liquid crystal cell was produced in the same manner as in Comparative Example 10 except that the amount of irradiation of ultraviolet rays after the polarizing was set to 500 mJ.

The production conditions of the liquid crystal alignment films of the liquid crystal cells produced in Examples 10 and 11 and Comparative Examples 5 to 8 are shown in Table 3.

[Evaluation of liquid crystal display elements]

In the liquid crystal alignment films of the liquid crystal cells obtained in Examples 10 and 11 and Comparative Examples 5 to 8, the alignment state of the liquid crystals was evaluated using a polarizing microscope (manufactured by Nikon Corporation).

Fig. 4 is a view showing comparison of liquid crystal cells of Examples 10 and 11 and Comparative Examples 5 to 8 with a polarizing microscope photograph.

As shown in Fig. 4, no defects were observed in the liquid crystal cells obtained in Examples 10 and 11. Further, the polarizing microscope was rotated under the orthogonal polarization, and it was confirmed that clear and dark light was generated, and it was confirmed that the liquid crystal was uniformly parallel aligned. The liquid crystal cell of Example 6 having an ultraviolet irradiation amount of 250 mJ was also subjected to sufficient alignment treatment.

On the other hand, the liquid crystal cells obtained in Comparative Examples 5 to 8 were observed to have many defects, and it was found that the liquid crystals were not uniformly aligned. The liquid crystal cell of Comparative Example 6 in which the ultraviolet irradiation amount was 500 mJ did not achieve uniform alignment of the liquid crystal, and was insufficiently aligned.

From the above observation results, it was found that the liquid crystal cells of Example 10 and Example 11 which were treated with heat treatment at 240 ° C during the irradiation of the ultraviolet light after the polarization were The alignment control of the liquid crystal can also be performed with a small amount of ultraviolet irradiation. Further, when the polarized ultraviolet ray is irradiated and heat-treated, the amount of ultraviolet ray required is about 250 mJ, which is a very small amount compared to the conventional photo-alignment method.

Next, using the liquid crystal cells obtained in Examples 10 and 11, each of the polarized plates was held in a crossed Nichol arrangement to constitute a liquid crystal display element. The obtained liquid crystal display elements were each applied with a voltage between the ITO electrodes on the substrate, and it was confirmed that the alignment of the liquid crystal was changed, and the amount of light transmitted was changed.

From the above evaluation results, it is known that the liquid crystal display element of the present invention produced by the method of producing a liquid crystal alignment film of the present invention can be provided with a liquid crystal display element which is produced by a small amount of ultraviolet irradiation.

[Example B]

The meaning of the abbreviations used in the examples is as follows.

CBDA: 1,2,3,4-cyclobutane tetracarboxylic dianhydride

p-PDA: p-phenylenediamine

NMP: N-methyl-2-pyrrolidone

BCS: Butyl Cyrus

APHFP:

Diamine [1]~[7]: a diamine represented by the following formula [1]~[7]

<Measurement of ¹ H-NMR>

The measurement conditions of ¹ H-NMR in the synthesis examples are as follows.

Device: Fourier transform type superconducting nuclear magnetic resonance apparatus (FT-NMR) INOVA-400 (manufactured by Varian) 400 MHz

Solvent: Deuterated dimethyl hydrazine (DMSO-d ₆ ) and deuterated chloroform (CDCl ₃ )

Reference material: 巳methyl decane (TMS)

<Measurement of molecular weight of polymer>

The measurement conditions of the molecular weight of the polymer (polyproline, etc.) are as follows Said.

Device: room temperature gel permeation chromatography (GPC) device (SSC-7200) manufactured by Senshu Scientific Co., Ltd.

Column: Shodex pipe column (KD-803, and KD-805)

Column temperature: 50 ° C

Dissolution: N,N'-dimethylformamide (additive lithium bromide-hydrate (LiBr‧H ₂ O) 30 mmol / L, anhydrous phosphate crystals (o-phosphoric acid) 30 mmol / L, tetrahydrofuran ( THF) is 10ml/L)

Flow rate: 1.0ml/min

Standard sample for calibration curve preparation: TSK standard polyethylene oxide (molecular weight of about 900,000, 150,000, 100,000, and 30,000) manufactured by Tosoh Corporation, and polyethylene glycol manufactured by Polymer Laboratories Ltd. (molecular weight of about 12,000, 4,000, and 1,000) ).

<Synthesis of diamine> (Synthesis Example 1)

Synthesis of Diamine [1]((E,E)-Bis-(4'-aminophenyl)1,4-benzenediacrylate)

Terephthalaldehyde [A] (40.00 g, 298 mmol), pyridine (46 g), and piperidine (7.0 g) were placed in a 2-L four-neck flask, and the reaction solution was heated to 100 ° C while stirring. Next, a solution of malonic acid [B] (140.0 g, 1.34 mol) in pyridine (500 g) was dropped into the reaction solution. After confirming the completion of the reaction by HPLC (High Speed Liquid Chromatography), the reaction solution was cooled to 40 ° C, and the reaction solution was poured into distilled water (1 L). Next, concentrated hydrochloric acid was added until the reaction solution became acidic, and then the solid was filtered. Then, it was washed with water, washed with methanol, and dried under reduced pressure to give compound [C] (yield: 60.3 g, yield: 93%). The results of ¹ H-NMR measurement of the obtained compound [C] are shown below.

¹ H-NMR (400 MHz, DMSO-d6, δ ppm): 12.4 (2H, brs), 7.74 (4H, s), 7.60 (2H, d), 6.61 (2H, d).

Next, a compound [C] (30.00 g, 138 mmol), 4-nitrophenol [D] (42.08 g, 303 mmol), 1-ethyl-3-(3-dimethyl) was added to a 1 L four-necked flask. Aminopropyl)carbodiimide hydrochloride (hereinafter referred to as EDC) (68.53 g, 358 mmol), 4-N,N-dimethylaminopyridine (hereinafter referred to as DMAP) (3.56 g, 27.5 mmol) And tetrahydrofuran (hereinafter referred to as THF) (600 g), and stirred at 23 °C. After confirming the completion of the reaction by HPLC, the reaction solution was poured into a mixed solution of ethyl acetate (500 mL) / distilled water (1 L), and the solid was filtered. Then, it was washed with a 1:1 mixed solution of ethyl acetate/methanol, and dried under reduced pressure to give compound [E] (yield: 60.6 g, yield: 96%). The results of ¹ H-NMR measurement of the obtained compound [E] are shown below.

^{1 H-NMR (400MHz, DMSO} -d6, δppm): 8.36-8.31 (4H, m), 7.92 (2H, d), 7.68 (4H, s), 7.40-7.37 (4H, m), 6.70 (2H, d).

Next, a compound [E] (63.30 g, 138 mmol), tin chloride (182.5 g, 962 mmol), THF (630 g), and distilled water (440 g) were added to a 2-liter four-neck flask, and the mixture was subjected to 70 ° C at 70 ° C. Heat and stir. After confirming the completion of the reaction by HPLC, after adding N,N-dimethylacetamide (1 L), the reaction solution was diluted with ethyl acetate (2.5 L), and sodium hydrogencarbonate was added until the by-product tin hydroxide was not precipitated. . Then, the supernatant was filtered, and the filtrate was separated to remove the aqueous layer. Then, the organic layer was washed successively with 1 L of a saturated aqueous sodium hydrogencarbonate solution (2 times) and brine (2 times), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was evaporated using an evaporator to give a crude product, and methanol (200 mL) was added, and the mixture was stirred at room temperature (23 ° C) for 30 minutes. Then, it was again filtered, washed with methanol, and dried under reduced pressure to give a diamine [1] (yield: 24.0 g, yield: 44%). The results of ¹ H-NMR measurement of the obtained diamine [1] are shown below. ^{1 H-NMR (400MHz, DMSO} -d6, δppm): 7.83 (4H, s), 7.79 (2H, d), 6.89 (2H, d), 6.81-6.78 (4H, m), 6.56-6.53 (4H, m), 5.04 (4H, brs).

(Synthesis Example 2)

Synthesis of Diamine [2]((E,E)-Bis-(4'-aminophenylethyl)1,4-benzenediacrylate)

In a 1 L four-necked flask, compound [C] (30.21 g, 138 mmol), 2-(4-nitrophenyl)ethanol [F] (50.91 g, 305 mmol), EDC (68.98 g, 360 mmol) were added. ), DMAP (3.38 g, 27.9 mmol), and THF (600 g) were stirred at 23 °C. After confirming the completion of the reaction by HPLC, the reaction solution was poured into a mixed solution of ethyl acetate (1 L) / distilled water (1 L), and the solid was filtered. Then, it was washed with a 1:1 mixed solution of ethyl acetate/methanol, and dried under reduced pressure to give compound [G] (yield: 70.9 g, yield: 99%).

Next, a compound [G] (71.48 g, 138 mmol), tin chloride (183.4 g, 969 mmol), THF (715 g), and distilled water (500 g) were added to a 2-liter four-necked flask, and the mixture was subjected to 70 ° C at 70 ° C. Heat and stir. After confirming the completion of the reaction by HPLC, after adding N,N-dimethylacetamide (1 L), the reaction solution was diluted with ethyl acetate (2.5 L), and sodium hydrogencarbonate was added until the by-product tin hydroxide was not precipitated. . Then, the supernatant was filtered, and the filtrate was separated to remove the aqueous layer. Then, the organic layer was washed successively with 1 L of a saturated aqueous sodium hydrogencarbonate solution (2 times) and brine (2 times), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was evaporated using an evaporator to give a crude product, and methanol (200 mL) was added, and the mixture was stirred at room temperature for 30 minutes. Then, it was again filtered, washed with methanol, and dried under reduced pressure to give a diamine [2] (yield: 30.6 g, yield: 48%). The results of ¹ H-NMR measurement of the obtained diamine [2] are shown below.

^{1 H-NMR (400MHz, DMSO} -d6, δppm): 7.66 (2H, d), 7.73 (4H, s), 7.60 (2H, d), 6.90-6.88 (4H, m), 6.66 (2H, d) , 6.45-6.46 (4H, m), 4.88 (4H, brs), 4.21 (4H, t), 2.75 (4H, t).

(Synthesis Example 3)

Synthesis of Diamine [3]((E,E)-Bis-(4'-aminophenyl)1,3-benzenediacrylate)

Terephthalaldehyde [H] (50.00 g, 373 mol), pyridine (78 g), and piperidine (9.5 g) were placed in a 2-L four-neck flask, and the reaction solution was heated to 100 ° C while stirring. Next, a solution of malonic acid [B] (169.5 g, 1.68 mol) in pyridine (600 g) was dropped into the reaction solution. After confirming the completion of the reaction by HPLC (High Speed Liquid Chromatography), the reaction solution was cooled to 40 ° C, and the reaction solution was poured into distilled water (1 L). Next, concentrated hydrochloric acid was added until the reaction solution became acidic, and then the solid was filtered. Then, it was washed with water to obtain a crude product of the compound [I]. This crude product was stirred in a 1:1 mixture of ethyl acetate / methanol and stirred at room temperature for 30 min. Then, the mixture was washed with ethyl acetate, and dried under reduced pressure to give compound [I] (yield: 80.2 g, yield: 99%). The results of ¹ H-NMR measurement of the obtained compound [I] are shown below.

¹ H-NMR (400 MHz, DMSO-d6, δ ppm): 12.4 (2H, brs), 8.07 (1H, s), 7.72 (2H, dd), 7.61 (2H, d), 7.46 (1H, t).

Next, a compound [I] (30.00 g, 138 mmol), 4-nitrophenol [D] (40.17 g, 289 mmol), EDC (63.26 g, 330 mmol), DMAP (3.36) were added to a 1 L four-necked flask. g, 27.5 mmol), and THF (600 g) were stirred at 23 °C. After confirming the completion of the reaction by HPLC, the reaction solution was poured into a mixed solution of ethyl acetate (500 mL) / distilled water (1 L), and the solid was filtered. Then, it was washed with ethyl acetate and dried under reduced pressure to give compound [J] (yield: 62.1 g, yield: 98%). The results of ¹ H-NMR measurement of the obtained compound [J] are shown below.

^{1 H-NMR (400MHz, DMSO} -d6, δppm): 8.37 (1H, s), 8.32-8.29 (4H, m), 7.92 (2H, d), 7.88 (2H, dd), 7.56-7.51 (5H, m), 7.08 (2H, d).

Next, a compound [J] (62.1 g, 135 mmol), tin chloride (182.5 g, 962 mmol), THF (630 g), and distilled water (630 g) were placed in a 2-liter four-neck flask, and the mixture was subjected to 70 ° C at 70 ° C. Heat and stir. After confirming the completion of the reaction by HPLC, the reaction solution was diluted with ethyl acetate (2 L), and sodium hydrogen carbonate was added until the tin hydroxide of the by-product was not precipitated. Then, the supernatant was filtered, and the filtrate was separated to remove the aqueous layer. Then, the organic layer was washed successively with 1 L of a saturated aqueous sodium hydrogencarbonate solution (2 times) and brine (2 times), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was evaporated using an evaporator to give a crude product, and methanol (200 mL) was added, and the mixture was stirred at room temperature for 30 minutes. Then, it was again filtered, washed with methanol, and dried under reduced pressure to give a diamine [3] (yield: 34.1 g, yield: 54%). The results of ¹ H-NMR measurement of the obtained diamine [3] are shown below.

^{1 H-NMR (400MHz, DMSO} -d6, δppm): 8.27 (1H, s), 7.82-7.77 (4H, m), 7.49 (1H, t), 6.96 (2H, d), 6.82-6.78 (4H, m), 6.56-6.53 (4H, m), 5.04 (4H, brs).

(Synthesis Example 4)

Synthesis of Diamine [4]((E,E)-Bis-(4'-aminophenylethyl)1,3-benzenediacrylate)

Next, a compound [I] (54.92 g, 252 mmol), 2-(4-nitrophenyl)ethanol [F] (92.58 g, 554 mmol), EDC (125.4 g, 654) were placed in a 1 L four-necked flask. Methyl), DMAP (6.15 g, 50.3 mmol), and THF (1.1 Kg) were stirred at 23 °C. After confirming the completion of the reaction by HPLC, ethyl acetate (1 L) / hexane (500 mL) / distilled water (1 L) was added to the reaction mixture, and the aqueous layer was removed by liquid separation. Then, the organic layer was washed three times with brine (1 L), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was distilled off using an evaporator to obtain a crude product of compound [K]. Methanol (300 g) was added to this crude product, and stirred at room temperature for 30 min. Then, the mixture was filtered and dried under reduced pressure to give Compound [K] (yield: 82.2 g, yield: 63%). The results of ¹ H-NMR measurement of the obtained compound [K] are shown below.

^{1 H-NMR (400MHz, DMSO} -d6, δppm): 8.17-8.14 (4H, m), 8.11 (1H, s), 7.70 (2H, dd), 7.62 (1H, s), 7.59-7.56 (5H, m), 7.42 (1H, t), 6.71 (2H, d), 4.41 (4H, t), 3.10 (4H, t).

Next, a compound [K] (82.21 g, 139 mmol), tin chloride (211.3 g, 1.11 mol), THF (820 g), and distilled water (820 g) were added to a 2-liter four-necked flask, and heated at 70 ° C. Stir. After confirming the completion of the reaction by HPLC, the reaction solution was diluted with ethyl acetate (2.5 L), and sodium hydrogen carbonate was added until the tin hydroxide of the by-product was not precipitated. Then, the supernatant was filtered, and the filtrate was separated to remove the aqueous layer. Then, the organic layer was washed successively with 1 L of a saturated aqueous sodium hydrogencarbonate solution (2 times) and brine (2 times), and the organic layer was dried over magnesium sulfate. After filtration, the solvent was evaporated using an evaporator to give a crude product, and methanol (200 mL) was added, and the mixture was stirred at room temperature for 30 minutes. Then, it was again filtered, washed with methanol, and dried under reduced pressure to give a diamine [4] (yield: 46.1 g, yield: 73%). The results of ¹ H-NMR measurement of the obtained diamine [4] are shown below.

^{1 H-NMR (400MHz, CDCl3} , δppm): 7.66 (2H, d), 7.63 (1H, s), 7.54-7.39 (1H, m), 7.07-7.04 (4H, m), 6.68-6.65 (4H, m), 6.45 (2H, d), 5.04 (4H, brs), 4.37 (4H, t), 2.91 (4H, t).

(Synthesis Example 5)

Diamine [5]((E)-4-aminophenethyl 3-(4-aminophenyl) Acrylate synthesis

Compound [M] (12.7 g, 65.8 mmol), 2-(4-nitrophenyl)ethanol [F] (10 g, 59.8 mmol), EDC (15 g, 77.7 mmol), DMAP (365 mg) were added to a 500 mL reaction vessel. 3 mmol) and 200 g of THF were mixed with nitrogen and stirred at room temperature. After the completion of the reaction, the reaction solution was poured into distilled water (2 L), and the obtained crystal was washed with isopropyl alcohol (100 g) to give the compound [N] (yield: 18.4 g, yield: 90%).

Next, the compound [N] (22.4 g, 65.5 mmol) obtained above, tin (II) chloride (80 g, 458.7 mmol), 200 g of THF, and 100 g of distilled water were added to a 500 mL reaction vessel, and the mixture was stirred under heating at 60 °C. After the completion of the reaction, the reaction solution was neutralized by adding sodium hydrogencarbonate, and extracted with ethyl acetate. After distilling off the solvent of the extract, the obtained yellow crystals were dried to give a diamine [5] (yield: 14.0 g, yield: 76%). The results of ¹ H-NMR measurement of the obtained diamine [5] are shown below.

^{1 H-NMR (400MHz, DMSO} -d6, δppm): 7.46 (1H, d), 7.37 (2H, d), 6.92 (2H, d), 6.56-6.47 (4H, m), 6.20 (1H, d) , 5.78 (2H, s), 4.89 (2H, s), 4.18 (2H, t), 2.74 (2H, t).

(Synthesis Example 6)

Synthesis of diamine [6]((2E,2'E)-pentane-1,5-diyl bis(3-(4-aminophenyl)acrylate)

Compound [M] (37.5 g, 160.2 mmol), compound [O] (6.4 g, 61.6 mmol), EDC (41.6 g, 172.5 mmol), DMAP (828 mg, 6.8 mmol), and THF 300 g were added to a 500 mL reaction vessel. Stir at room temperature. After the completion of the reaction, the reaction solution was poured into distilled water (2 L) to precipitate crystals. The precipitated crystals were dried under reduced pressure to give Compound [P] (30 g).

Next, the compound [P] (15 g, 33.0 mmol) obtained above, tin (II) chloride (43.8 g, 231.0 mmol), 150 g of THF, and 150 g of distilled water were added to a 500 mL reaction vessel, and the mixture was stirred under heating at 60 °C. After the completion of the reaction, the reaction solution was neutralized by adding sodium hydrogencarbonate, and extracted with ethyl acetate. After distilling off the solvent of the extract, the obtained yellow crystals were washed successively with ethyl acetate and hexane to obtain a diamine [6] (yield: 11.9 g, yield: 91%). The results of ¹ H-NMR measurement of the obtained diamine [6] are shown below.

¹ H-NMR (400 MHz, DMSO-d6, δ ppm): 7.47 (2H, d), 7.36 (4H, d), 6.55 (4H, d), 6.22 (2H, d), 5.76 (4H, s), 4.10 (4H, t), 1.99-1.63 (4H, m), 1.46-1.40 (2H, m).

(Synthesis Example 7)

Synthesis of diamine [7]((E)-4-aminophenyl 3-(4-aminophenyl)acrylate

Compound [M] (34 g, 193.2 mmol), compound [D] 25.0 g, 179.7 mmol), EDC (40.4 g, 191.7 mmol), DMAP (2.2 g, 18 mmol), and THF 300 g were added to a 500 mL reaction vessel. Stir at room temperature. After the completion of the reaction, the reaction solution was poured into distilled water (3 L), and the precipitated white crystals were obtained by filtration. The obtained crude crystals were washed with isopropyl alcohol (200 g) to give Compound [Q] (52 g, 165.7 mmol).

Next, the above-obtained compound [Q] (30 g, 95.5 mmol), reduced iron (21.0 g, 382 mmol), ammonium chloride chloride (40.8 g, 762.8 mmol), N, N- were added to a 2 L reaction vessel. 200 g of dimethylformaldehyde, 200 g of ethyl acetate, and 400 g of distilled water were heated and stirred at 70 °C. After the reaction was completed, it was extracted with ethyl acetate and subjected to activated carbon treatment. Then, the solvent was distilled off by filtration to obtain a crude crystal. The obtained crude crystals were washed with methanol and hexane, and purified to obtain a diamine [7] (yield: 19.4 g, yield: 80%). The results of ¹ H-NMR measurement of the obtained diamine [7] are shown below.

^{1 H-NMR (400MHz, DMSO} -d6, δppm): 7.60 (1H, d), 7.43 (2H, d), 6.78 (2H, d), 6.77-6.36 (4H, m), 6.10 (1H, d) , 5.85 (2H, s), 5.02 (2H, s).

(Comparative Synthesis Example 1) Synthesis of diamine DA-1

According to Example 1 of JP-A-2001-517719, diamine DA-1 was synthesized.

<Modulation of Liquid Crystal Alignment Treatment Agent> (liquid crystal alignment treatment agent A1)

After adding NMP (5.0 g) to diamine [1] (1.20 g, 3.0 mmol), and completely dissolving at room temperature, CBDA (0.53 g, 2.8 mmol) and NMP (5.0 g) were added and reacted at room temperature. A polyaminic acid solution was obtained in 10 hours. To the polyamic acid solution (10 g), NMP (10.0 g) and BCS (5.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A1. The polyamine has a number average molecular weight of 6,000 and a weight average molecular weight of 10,500.

(liquid crystal alignment agent A2)

After adding NMP (5.4 g) to diamine [2] (1.37 g, 3.0 mmol), and completely dissolving at room temperature, CBDA (0.55 g, 2.8 mmol) and NMP (5.4 g) were added and reacted at room temperature. A polyaminic acid solution was obtained in 10 hours. To the polyamic acid solution (10 g), NMP (10.0 g) and BCS (5.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A2. The polyamine has a number average molecular weight of 3,800 and a weight average molecular weight of 5,000.

(Liquid crystal alignment agent A3)

After adding NMP (5.0 g) to diamine [3] (1.20 g, 3.0 mmol), and completely dissolving at room temperature, CBDA (0.55 g, 2.8 mmol) and NMP (5.0 g) were added and reacted at room temperature. A polyaminic acid solution was obtained in 10 hours. To the polyamic acid solution (10 g), NMP (10.0 g) and BCS (5.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A3. The polyamino acid had a number average molecular weight of 8,100 and a weight average molecular weight of 16,000.

(liquid crystal alignment agent A4)

After adding NMP (5.4 g) to diamine [4] (1.37 g, 3.0 mmol) and stirring at room temperature to dissolve completely, CBDA (0.55 g, 2.8 mmol) and NMP (5.4 g) were added and reacted at room temperature. A polyaminic acid solution was obtained in 10 hours. To the polyamic acid solution (10 g), NMP (10.0 g) and BCS (5.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A4. The polyamino acid has a number average molecular weight of 5,200 and a weight average molecular weight. It is 7600.

(liquid crystal alignment agent A5)

After adding NMP (32.3 g) to diamine [5] (7.06 g, 25.0 mmol) and stirring at room temperature to dissolve completely, CBDA (4.51 g, 23.0 mmol) and NMP (33.2 g) were added and reacted at room temperature. A polyaminic acid solution was obtained in 10 hours. To the polyamic acid solution (40 g), NMP (40.0 g) and BCS (20.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A5. The polyamine has a number average molecular weight of 10,500 and a weight average molecular weight of 57,000.

(liquid crystal alignment agent A6)

After adding NMP (4.9 g) to diamine [6] (1.18 g, 3.0 mmol), and completely dissolving at room temperature, CBDA (0.53 g, 2.7 mmol) and NMP (4.9 g) were added and reacted at room temperature. A polyaminic acid solution was obtained in 10 hours. To the polyamic acid solution (10 g), NMP (10.0 g) and BCS (5.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A6. The polyamino acid had a number average molecular weight of 8,800 and a weight average molecular weight of 35,000.

(Liquid alignment treatment A7)

After adding NMP (5.6 g) to diamine [7] (1.14 g, 4.5 mmol) and stirring at room temperature to dissolve completely, CBDA (0.83 g, 4.2 mmol) and NMP (5.6 g) were added and reacted at room temperature. 10 hours to get polylysine Solution. To the polyamic acid solution (10 g), NMP (10.0 g) and BCS (5.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A7. The polyamino acid had a number average molecular weight of 13,800 and a weight average molecular weight of 35,500.

(liquid crystal alignment agent A8)

NMP (27.0 g) was added to the diamine [5] (3.53 g, 12.5 mmol) and p-PDA (1.35 g, 12.5 mmol), and after stirring at room temperature to dissolve completely, CBDA (4.66 g, 23.8 mmol) was added. It was reacted with NMP (27.0 g) at room temperature for 10 hours to obtain a polyaminic acid solution. To the polyamic acid solution (40 g), NMP (40.0 g) and BCS (20.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment agent A8. The polyamine has a number average molecular weight of 1,1,500 and a weight average molecular weight of 25,000.

(Liquid alignment treatment agent B1)

After adding NMP (22.0 g) to DA-1 (5.10 g, 14.0 mmol), and completely dissolving at room temperature, CBDA (2.66 g, 13.6 mmol) and NMP (22.0 g) were added and reacted for 5 hours at room temperature. A polylysine solution was obtained. To the polyamic acid solution (40 g), NMP (40.0 g) and BCS (20.0 g) were added, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal alignment treatment agent B1. The polyamine has a number average molecular weight of 6,500 and a weight average molecular weight of 26,000.

(Example 1)

Using the liquid crystal alignment agent A1, liquid crystal cells were produced in the order shown below.

A glass substrate having a substrate of a size of 30 mm × 40 mm and a thickness of 0.7 mm is provided with a comb-shaped pixel electrode in which an ITO film is patterned. The pixel electrode has a comb-tooth shape in which the electrode elements of the U-shape in which the central portion is curved are arranged in a plurality of rows. The width of each electrode element in the width direction was 3 μm, and the interval between the electrode elements was 6 μm. Since the electrode elements forming the U-shaped portion in which the central portion of the pixel electrode system of each pixel is curved are arranged in a plurality of rows, the shape of each pixel is not rectangular, and is curved in the central portion like the electrode element, similar to the shape of a thick letter. . Each of the pixels is divided into upper and lower sides by a curved portion at the center, and has a first region on the upper side of the curved portion and a second region on the lower side. When the first region and the second region of each pixel are compared, the direction in which the electrode elements constituting the pixel electrodes are formed is different. In other words, when the alignment processing direction of the liquid crystal alignment film described later is the reference, the electrode element of the pixel region of the first region of the pixel is formed at an angle of +10° (clockwise), and the second region of the pixel is the electrode element of the pixel electrode. Formed at an angle of -10° (clockwise). In other words, the first region and the second region of each pixel are configured such that the directions of the rotation (horizontal alignment) of the liquid crystal in the substrate surface caused by the application of a voltage between the pixel electrode and the counter electrode are opposite to each other. .

The liquid crystal alignment agent A1 was spin-coated on the substrate on which the above-mentioned electrode was prepared. Subsequently, the film was dried on a hot plate at 90 ° C for 60 seconds, and then fired in a hot air circulating oven at 200 ° C for 30 minutes to form a liquid crystal alignment film having a film thickness of 100 nm. Next, the substrate was placed on a hot plate at 240 ° C, and the liquid crystal alignment film surface was irradiated with ultraviolet rays of 313 nm at 20 mJ/cm ^{2 on the} polarizing plate to obtain a substrate with a liquid crystal alignment film. In the same manner as described above, the liquid crystal alignment treatment agent A1 is used to form the liquid crystal alignment film to be subjected to the alignment treatment in the glass substrate having the columnar spacers having a height of 4 μm in which the electrode is not formed.

A sealant (XN-1500T, manufactured by Kyoritsu Chemical Co., Ltd.) was printed on the liquid crystal alignment film of one of the substrates. Next, the other substrate is placed so that the liquid crystal alignment film faces and the alignment direction becomes 0°, and then the sealant is cured to form an empty liquid crystal cell. The liquid crystal cell was injected into the liquid crystal MLC-2041 (manufactured by Merck) by a vacuum injection method, and the liquid crystal cell having an IPS (In-Planes Switching) mode liquid crystal display element was obtained by closing the injection port (liquid crystal cell for IPS mode). .

(Liquid alignment performance evaluation)

The alignment state of the liquid crystal cell for IPS mode obtained as described above was observed with a polarizing microscope, and those who had no alignment defects were evaluated as "good", and those who had alignment defects were evaluated as "poor". The results are shown in Table 4.

(afterimage evaluation)

The IPS mode liquid crystal cell obtained as described above is disposed between two polarizing plates in which the polarizing axes are arranged orthogonally, and the light source is turned on in a state where the voltage is not applied, and the arrangement angle of the liquid crystal cells is adjusted to minimize the brightness of the transmitted light. . Next, the rotation angle (alignment azimuth angle) when the liquid crystal cell is rotated from the second region of the pixel to the darkest angle to the darkest angle of the first region is calculated as the initial alignment azimuth angle. Next, an alternating voltage of a frequency of 30 Hz and 8 V _PP was applied for 24 hours at room temperature. Then, a short-circuit state was formed between the pixel electrode of the liquid crystal cell and the counter electrode, and in this state, it was allowed to stand at room temperature for 1 hour. After the placement, the alignment azimuth angle is also measured, and the difference between the azimuth angles before and after the AC drive, that is, (the azimuth angle before the AC drive) - (the azimuth angle after the AC drive) is calculated by the Δ azimuth angle (°). The results are shown in Table 4.

(Example 2)

The liquid crystal alignment performance evaluation and afterimage evaluation were performed in the same manner as in Example 1 except that the liquid crystal alignment treatment agent A2 was used instead of the liquid crystal alignment treatment agent A1.

(Example 3)

The liquid crystal alignment performance evaluation and afterimage evaluation were performed in the same manner as in Example 1 except that the liquid crystal alignment agent A3 was used instead of the liquid crystal alignment agent A1.

(Example 4)

The liquid crystal alignment performance evaluation and afterimage evaluation were performed in the same manner as in Example 1 except that the liquid crystal alignment treatment agent A4 was used instead of the liquid crystal alignment treatment agent A1.

(Example 5)

The liquid crystal alignment performance evaluation and afterimage evaluation were performed in the same manner as in Example 1 except that the liquid crystal alignment treatment agent A5 was used instead of the liquid crystal alignment treatment agent A1.

(Example 6)

The liquid crystal alignment performance evaluation and afterimage evaluation were performed in the same manner as in Example 1 except that the liquid crystal alignment treatment agent A6 was used instead of the liquid crystal alignment treatment agent A1.

(Example 7)

The liquid crystal alignment performance evaluation and afterimage evaluation were performed in the same manner as in Example 1 except that the liquid crystal alignment agent A7 was used instead of the liquid crystal alignment treatment agent A1.

(Example 8)

The liquid crystal alignment performance evaluation and afterimage evaluation were performed in the same manner as in Example 1 except that the liquid crystal alignment agent A8 was used instead of the liquid crystal alignment agent A1.

As a result, as shown in Table 4, a specific photoreactive group was introduced into the poly(diamine) represented by the above formula (4) as a raw material even at a low temperature and a short time measurement condition at room temperature for 24 hours. In Examples 1 to 6 of the main chain skeleton of the quinone imine polymer, the difference in the orientation azimuth angle before and after the AC driving was small as compared with Comparative Example 1, and the afterimage characteristics were remarkably improved. Further, in Examples 1 to 6, the liquid crystal alignment property was good. Further, Example 7 in which other diamines were copolymerized also showed good liquid crystal alignment properties and AC charring characteristics. In other words, by using the liquid crystal alignment treatment agent of the present invention, a liquid crystal alignment film having excellent liquid crystal alignment properties and afterimage characteristics can be obtained. In addition, the liquid crystal display element having the liquid crystal alignment film obtained by the liquid crystal alignment treatment agent of the present invention is excellent in liquid crystal alignment property and afterimage characteristics, and thus a liquid crystal display device which is less likely to cause display failure, contrast reduction, charring, and the like can be obtained.

<Comparative Example 9>

Using the liquid crystal alignment treatment agent A1, liquid crystal alignment performance was evaluated in the same manner as in Example 1 except that the liquid crystal alignment film surface was placed on a polarizing plate at room temperature and irradiated with ultraviolet rays of 313 nm at 20 mJ/cm ² .

<Comparative Example 10>

The liquid crystal alignment performance evaluation was performed in the same manner as in Comparative Example 9 except that the liquid crystal alignment treatment agent A2 was used instead of the liquid crystal alignment treatment agent A1.

<Comparative Example 11>

The liquid crystal alignment performance evaluation was performed in the same manner as in Comparative Example 9 except that the liquid crystal alignment treatment agent A3 was used instead of the liquid crystal alignment treatment agent A1.

<Comparative Example 12>

The liquid crystal alignment performance evaluation was performed in the same manner as in Comparative Example 9 except that the liquid crystal alignment agent A4 was used instead of the liquid crystal alignment treatment agent A1.

<Comparative Example 13>

The liquid crystal alignment performance evaluation was performed in the same manner as in Comparative Example 9, except that the liquid crystal alignment treatment agent A5 was used instead of the liquid crystal alignment treatment agent A1.

<Comparative Example 14>

The liquid crystal alignment performance evaluation was performed in the same manner as in Comparative Example 9, except that the liquid crystal alignment agent A7 was used instead of the liquid crystal alignment treatment agent A1.

<Comparative Example 15>

The liquid crystal alignment performance evaluation was performed in the same manner as in Comparative Example 9 except that the liquid crystal alignment treatment agent A8 was used instead of the liquid crystal alignment treatment agent A1.

Next, the liquid crystal alignment properties of the liquid crystal cells obtained in the above Examples 1 to 7 and the liquid crystal alignment properties of the liquid crystal cells obtained in the following Comparative Examples 9 to 15 are shown in Table 5.

As shown in Table 5, it was found that while the heat treatment was performed at 240 ° C, the polarized ultraviolet rays were irradiated to improve the liquid crystal alignment property. This is caused by the fact that the heat treatment is carried out while irradiating ultraviolet rays to promote the photodimerization reaction of the cinnamyl group.

[Industrial availability]

According to the present invention, a high photoreaction efficiency can be achieved, and a liquid crystal alignment film which can be efficiently treated with an alignment can be obtained. By using the liquid crystal alignment film, it is possible to provide a film which is easy to produce even when it is used for a long period of time. A liquid crystal display element in which the alignment state of the liquid crystal changes.

Fig. 1 is a view showing an ultraviolet absorption spectrum of a liquid crystal alignment film before alignment treatment obtained in Example 3 of Example [A) and a liquid crystal alignment film obtained in Example 5.

2 is an ultraviolet absorption spectrum of a liquid crystal alignment film before alignment treatment obtained in Example 3 of [Example A] and a liquid crystal alignment film obtained in Comparative Examples 1 and 2.

3 is an ultraviolet absorption spectrum of a liquid crystal alignment film obtained in Example 9 of [Example A] and a liquid crystal alignment film obtained in Comparative Examples 3 and 4.

Fig. 4 is a photomicrograph of a liquid crystal alignment film in liquid crystal cells obtained in Examples 10 and 11 and Comparative Examples 5 to 8 of Example A, which was photographed using a polarizing microscope.

Claims (10)

A method for producing a liquid crystal alignment film, characterized in that a film containing a photoreactive group of a polyimide or a polyimide precursor is formed on a substrate, and the front film is heated while irradiating the polarized ultraviolet light. A liquid crystal alignment film comprising a polymer having a photoreactive group, wherein the polyimine precursor having a photoreactive group contains a repeating unit represented by the following formula [1] and The repeating unit represented by the formula [2] or the repeating unit represented by the following formula [1] and the repeating unit represented by the following formula [3], (In the formula [1], R ₁ represents a divalent organic group, R ₂ represents a tetravalent organic group, R ₃ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms, and R ₄ represents a hydrogen atom or a carbon number. 1 to 6 organic groups, n ₁ represents a positive integer) (In the formula [2], R ₅ represents a divalent organic group constituting a photoreactive group, R ₆ represents a tetravalent organic group, R ₇ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms, and R ₈ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms, and n ₂ represents a positive integer) (In the formula [1], R ₁ represents a divalent organic group, R ₂ represents a tetravalent organic group, R ₃ represents a hydrogen atom or an organic group having 1 to 6 carbon atoms, and R ₄ represents a hydrogen atom or a carbon number. 1 to 6 organic groups, n ₁ represents a positive integer) (In the formula [3], R ₉ represents a divalent organic group, R ₁₀ represents a divalent organic group constituting a photoreactive group, and n ₃ represents a positive integer). The method for producing a liquid crystal alignment film according to the first aspect of the invention, wherein the polyimine precursor having a photoreactive group is a diamine component having a diamine represented by the following formula [4] and a tetracarboxylic acid The anhydride is subjected to a polycondensation reaction, (In the formula [1], X ¹ represents a single bond or an alkylene group having 1 to 6 carbon atoms (but a non-adjacent -CH ₂ - may be substituted into an ether bond, an ester bond or a guanamine bond), and X ² represents - OCO-CH=CH- or -CH=CH-COO-, X ³ represents a single bond, an alkylene group having a carbon number of 1 to 10 or a divalent benzene ring, and X ⁴ represents a single bond, -OCO-CH=CH- or - CH=CH-COO-, X ⁵ represents a single bond or an alkylene group having 1 to 6 carbon atoms (but not adjacent -CH ₂ - may be substituted into an ether bond, an ester bond or a guanamine bond), formula [4] ] has one or more cinnamon sulfhydryl groups). The method for producing a liquid crystal alignment film according to the first aspect of the invention, wherein the film has a thickness of 5 to 300 nm. The method for producing a liquid crystal alignment film according to the first aspect of the invention, wherein the content of the photoreactive group-containing polyimine precursor is 0.1 to 30% by mass, and the film is formed using a liquid crystal alignment treatment agent containing a solvent. The method for producing a liquid crystal alignment film according to the first aspect of the invention, wherein the heating temperature is selected from a temperature at which the polyimine precursor having a photoreactive group does not become a temperature range of the polyimide. The method for producing a liquid crystal alignment film according to the first aspect of the invention, wherein the heating temperature is in a range of from 50 ° C to 300 ° C. The method for producing a liquid crystal alignment film according to the first aspect of the invention, wherein the heating temperature is in a range of from 80 ° C to 250 ° C. The method for producing a liquid crystal alignment film according to the first aspect of the invention, wherein the ultraviolet ray irradiation amount is 100 to 1000 mJ. A liquid crystal alignment film produced by the method for producing a liquid crystal alignment film according to any one of claims 1 to 8. A liquid crystal display element characterized by having a liquid crystal alignment film according to claim 9 of the patent application.