TW201627354A - Liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display element using same - Google Patents

Abstract

A liquid crystal aligning agent which contains at least one polymer selected from among polyamic acids, which are obtained using a tetracarboxylic acid dianhydride component containing an aromatic tetracarboxylic acid dianhydride and a diamine component containing a diamine represented by formula (1), and polyimides which are obtained by imidizing the polyamic acids. In the formula, R1 represents a hydrogen atom or a monovalent organic group; Q1 represents an alkylene group having 1-5 carbon atoms; Cy represents a divalent group that is an aliphatic heterocyclic ring composed of azetidine, pyrrolidine, piperidine or hexamethyleneimine, and a substituent may be bonded to a ring portion thereof; each of R2 and R3 represents a monovalent organic group; and each of q and r independently represents an integer of 0-4. In this connection, in cases where the total of q or r is 2 or more, each one of the plurality of R2 moieties or R3 moieties independently represents a monovalent organic group.

Description

Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element thereof

The present invention relates to a liquid crystal alignment agent used for a liquid crystal display element, a liquid crystal alignment film, and a liquid crystal display element using the same.

For liquid crystal display elements such as liquid crystal televisions and liquid crystal displays, a liquid crystal alignment film that normally controls the arrangement state of liquid crystals is provided in the element. As a liquid crystal alignment film, a liquid crystal alignment agent containing a solution of a polyamidene precursor such as polyglycine (polyglycine) or a solution of a soluble polyimine is mainly applied to a glass substrate or the like and fired. Polyimine-based liquid crystal alignment film.

With the high definition of the liquid crystal display element, in view of the suppression of the contrast reduction of the liquid crystal display element or the reduction of the residual image development, in addition to the performance of the liquid crystal alignment film, in addition to the excellent liquid crystal alignment or the stable pretilt angle, Characteristics such as high voltage holding ratio, afterimage suppression by AC driving, less residual charge when a DC voltage is applied, and/or rapid relaxation of residual charges accumulated by a DC voltage are becoming more and more important.

In the case of the polyimine-based liquid crystal alignment film, various proposals have been made in response to the above requirements. For example, as the DC voltage is reached A liquid crystal alignment film having a relatively short period of disappearance of the generated afterimage, using a poly-proline or a ruthenium-containing polyphthalic acid, and a liquid crystal alignment agent containing a specific structure of a tertiary amine (for example, reference) Patent Document 1) or a liquid crystal alignment agent containing a soluble polyimine which is a raw material having a pyridine skeleton or the like as a raw material (see, for example, Patent Document 2) is proposed. In addition, as a liquid crystal alignment film having a high voltage holding ratio and a residual image generated by a DC voltage and having a short disappearance time, it is also used in a molecule other than polyacrylic acid or a ruthenium iodide polymer thereof. A compound containing one carboxylic acid group, a compound containing one carboxylic acid anhydride group in the molecule, and a compound selected from a compound containing one tertiary amino group in the molecule, and a liquid crystal alignment agent contained in a very small amount (for example, reference patent) Document 3).

In addition, as a liquid crystal alignment film which is excellent in liquid crystal alignment, high in voltage retention ratio, small in residual image, and excellent in reliability, and exhibits a high pretilt angle, it is known to use four kinds of tetracarboxylic dianhydride and cyclobutane having a specific structure. A liquid crystal alignment agent of a polyamic acid or a quinone imidized polymer obtained by using a carboxylic acid dianhydride and a specific diamine compound (for example, refer to Patent Document 4). Further, as a method of suppressing an afterimage caused by an AC drive generated in a liquid crystal display device of a lateral electric field drive method, a method of using a specific liquid crystal alignment film having a good liquid crystal alignment property and having a large interaction with liquid crystal molecules has been used. (refer to Patent Document 5) is proposed.

However, in recent years, large-screen and high-definition liquid crystal televisions have become mainstream, and the demand for afterimages has become severe, and the long-term use characteristics that can withstand in a severe use environment are required. At the same time, the liquid crystal alignment film used must have higher reliability than in the past, and the characteristics of the liquid crystal alignment film, Not only is the initial characteristics good, but for example, it is expected to maintain good characteristics even after exposure to a high temperature for a long period of time.

On the other hand, it has been reported that as a polymer component constituting a polyimine-based liquid crystal alignment agent, the polyglycolate is subjected to heat treatment by imidization of the ruthenium, so that molecular weight reduction is not caused. The alignment stability of the liquid crystal is excellent in reliability (see Patent Document 6). Polyurethanes generally have problems such as high volume resistivity and high residual charge when DC voltage is applied, and poly-phthalate and poly-proline-adjusted liquid crystal alignment agent with excellent electrical properties have been revealed ( Refer to Patent Document 7).

[Advanced technical literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. Hei 9-316200

[Patent Document 2] Japanese Patent Laid-Open No. Hei 10-104633

[Patent Document 3] Japanese Patent Laid-Open No. Hei 8-76128

[Patent Document 4] Japanese Patent Laid-Open No. Hei 9-138414

[Patent Document 5] Japanese Patent Laid-Open No. Hei 11-38415

[Patent Document 6] Japanese Patent Laid-Open Publication No. 2003-26918

[Patent Document 7] WO2011/15080

As described above, liquid crystal alignment corresponding to various requirements has been disclosed Agents, but new topics have recently emerged.

Compared with the past, recent liquid crystal display elements have become more mainstream for the design of effective pixel regions in the frontal region. Therefore, when the sealing component applied in the fore edge region is dissolved in the liquid crystal, it diffuses into the effective pixel region, which causes a problem of display failure. In order to solve this problem, when the sealing component is dissolved in the liquid crystal, the image of the afterimage is not expected to be changed.

The inventors of the present invention have made a detailed review of the above problems, and have found that a liquid crystal alignment film which satisfies the above-mentioned problems can be obtained by using a tetracarboxylic dianhydride having a specific structure and a diamine compound having a specific structure. The present invention has been completed. The present invention is based on the above findings and is intended to be as follows.

A liquid crystal alignment agent characterized by comprising a polymer of at least one of the following polyimines; the polyimide is made of a tetracarboxylic dianhydride component containing an aromatic tetracarboxylic dianhydride and containing a polyamic acid obtained from the diamine component of the diamine of the formula (1) and obtained by subjecting the ruthenium to ruthenium;

R ₁ represents hydrogen or a monovalent organic group, Q ₁ represents an alkylene group having 1 to 5 carbon atoms, and Cy represents a fat derived from azetidine, pyrrolidine, piperidine or hexamethyleneimine. a divalent group of a heterocyclic ring, a substituent may be bonded to these ring moieties, R ₂ and R ₃ are monovalent organic groups, and q and r are each independently an integer of 0 to 4; however, the total of q or r is 2 In the above, the plural R ₂ and R ₃ independently have the above definitions.

2. The liquid crystal complexing agent according to ₁ , wherein R ₁ is an alkyl group having 1 to 3 carbon atoms, a hydrogen atom, or a thermally detachable group which may be substituted by a heat to a hydrogen atom, and R ₂ and R _{3 are} each independently A hydrogen atom, a methyl group, a trifluoromethyl group, a cyano group, or a methoxy group.

3. The liquid crystal alignment agent according to 1. or 2. wherein R ₁ is a linear alkyl group having 1 to 3 carbon atoms, a hydrogen atom or a tert-butoxycarbonyl group, and Cy is a pyrrolidine ring or a piperidine ring.

4. The liquid crystal alignment agent according to any one of the items 1 to 3, which contains the diamine compound represented by the following general formula (2).

In the formula (2), R ₁ is a hydrogen atom, a methyl group or a tert-butoxycarbonyl group, R ₂ is a hydrogen atom or a methyl group, and Q ₁ is a linear alkylene group having 1 to 5 carbon atoms.

5. The liquid crystal alignment agent according to any one of 1. to 4. wherein the aromatic tetracarboxylic acid The acid dianhydride is 20 mol% or more of the total tetracarboxylic dianhydride component.

6. The liquid crystal alignment agent according to any one of 1. to 5, wherein the aromatic tetracarboxylic dianhydride is pyromellitic dianhydride.

The liquid crystal alignment agent of any one of the above-mentioned formula (1), wherein the diamine of the above formula (1) is 30 mol% or more with respect to the aromatic tetracarboxylic dianhydride.

A liquid crystal alignment film which is obtained by the liquid crystal alignment agent of any one of 1. to 7.

A liquid crystal display element comprising a liquid crystal alignment film of 8.

The present invention provides a mitigating property without lowering the liquid crystal alignment property or the accumulated electric charge. Even in the case where the liquid crystal is contaminated by the sealing component, it is difficult to change the cumulative DC charge amount, in other words, it is difficult to produce a display by the influence of the sealing component. A poor liquid crystal alignment film and a liquid crystal display element using the same.

[Formation of the Invention]

The invention is described in detail below.

The liquid crystal alignment agent of the present invention is a polymer containing at least one of the following polyimines, which is a tetracarboxylic dianhydride component containing an aromatic tetracarboxylic dianhydride and contains the above formula (1). a polyimine precursor obtained from a diamine diamine component and a polyfluorene obtained by imidating the hydrazine Imine.

<aromatic tetracarboxylic dianhydride>

An aromatic tetracarboxylic dianhydride is used in the liquid crystal alignment agent of the present invention. This type can be used, or two or more types can be mixed. Examples of the tetracarboxylic acid to be used as a raw material for the aromatic tetracarboxylic dianhydride include pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, and 1,2,5,6-naphthalenetetracarboxylic acid. Acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-nonanedicarboxylic acid, 1,2,5,6-nonanedicarboxylic acid, 3,3',4,4' -biphenyltetracarboxylic acid, 2,3,3',4-biphenyltetracarboxylic acid, bis(3,4-dicarboxyphenyl)ether, 3,3',4,4'-diphenyl Ketotetracarboxylic acid, bis(3,4-dicarboxyphenyl)anthracene, 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)dimethylnonane, double (3 , 4-dicarboxyphenyl)diphenylnonane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis(3,4-dicarboxyphenyl)pyridine, etc., but by alignment of liquid crystals And from the viewpoint of reducing afterimage, pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 3,3' , 4,4'-benzophenone tetracarboxylic acid, bis(3,4-dicarboxyphenyl) ether, etc., especially pyromellitic acid, 3,3',4,4'-biphenyltetracarboxylic acid It is better.

The aromatic tetracarboxylic dianhydride is preferably 20 mol% or more of the total tetracarboxylic dianhydride component used for the synthesis of the polymer contained in the liquid crystal alignment agent of the present invention.

<Other tetracarboxylic dianhydride>

When synthesizing the polyamic acid used in the liquid crystal alignment agent of the present invention, In the range which does not impair the effect of the present invention, other tetracarboxylic dianhydrides may be used in addition to the above aromatic tetracarboxylic dianhydride. Specific examples of other tetracarboxylic dianhydrides include the following.

Examples of the tetracarboxylic acid to obtain a raw material of the aliphatic tetracarboxylic dianhydride include 1,2,3,4-cyclobutanetetracarboxylic acid and 1,2,3,4-cycloheptanetetracarboxylic acid. 2,3,4,5-tetrahydrofuran tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 1,2,4,5-pentanetetracarboxylic acid, 1,2,4,5-ring Hexanetetracarboxylic acid, 3,4-dicarboxy-1-cyclohexyl succinic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid, bicyclo[3,3 , 0] octane-2,4,6,8-tetracarboxylic acid, 1,2,3,4-cycloheptane tetracarboxylic acid, 2,3,4,5-tetrahydrofuran tetracarboxylic acid, 1,2, 4,5-cyclohexanetetracarboxylic acid, 3,4-dicarboxy-1-cyclohexyl succinic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid, Ring [3,3,0]octane-2,4,6,8-tetracarboxylic acid, etc., but from the viewpoint of liquid crystal alignment, 1,2,3,4-cyclobutanetetracarboxylic acid or These derivatives are preferred. Further, from the viewpoint that the liquid crystal display element for driving the transverse electric field must have a low pretilt angle, it is a ring-ring [3,3,0]octane-2,4,6,8-tetracarboxylic acid, 1, 2,3,4-butanetetracarboxylic acid and 1,2,4,5-pentanetetracarboxylic acid are preferred.

1,2,3,4-cyclobutanetetracarboxylic acid or a dianhydride of these derivatives selected from the group consisting of bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic acid, 1, When at least one tetracarboxylic dianhydride of 2,3,4-butanetetracarboxylic acid or 1,2,4,5-pentanetetracarboxylic acid dianhydride is used in combination, good liquid crystal alignment and lower pre-preparation can be achieved. Both sides of the dip are preferred.

<specific diamine>

When used for synthesizing polyamic acid used in the liquid crystal alignment agent of the present invention The specific diamine is represented by the following formula (1).

R ₁ represents hydrogen or a monovalent organic group, preferably a hydrogen atom, a linear alkyl group having 1 to 3 carbon atoms, or a protective group substituted with a hydrogen atom by a heat-releasing reaction, preferably a hydrogen atom or a methyl group. Alternatively, the protective group is replaced by a hydrogen atom by heat generation.

The protective group substituted with a hydrogen atom by heat generation is replaced by a liquid crystal alignment agent from the viewpoint of storage stability of the liquid crystal alignment agent, and is preferably not removed at room temperature, and is preferably a protective group which is desorbed under heat of 80 ° C or higher. More preferably, the protective group is detached under heat of 100 ° C or higher. Examples of such a protecting group include 1,1-dimethyl-2-chloroethoxycarbonyl, 1,1-dimethyl-2-cyanoethoxycarbonyl, and tert-butoxycarbonyl. More specifically, tert-butoxycarbonyl group is mentioned.

Q ₁ represents an alkylene group having 1 to 5 carbon atoms, and is preferably a linear alkylene group having a carbon number of 1 to 5 as a simple synthetic property.

Cy represents a divalent group of an aliphatic heterocyclic ring formed of azetidine, pyrrolidine, piperidine or hexamethylenemethylimine, and azetidine, pyrrolidine, Piperidine is preferred. Also, these ring moieties may bond substituents.

R ₂ and R ₃ are a monovalent organic group, and q and r are each independently an integer of 0 to 4. However, when the total of q or r is 2 or more, a plurality of R ₂ and R ₃ independently have the above definitions. It is preferred that R ₂ and R ₃ each independently represent a hydrogen atom, a methyl group, a trifluoromethyl group, a cyano group or a methoxy group. From the viewpoint of ease of synthesis, a hydrogen atom or a methyl group is preferred. Further, the bonding position of the amine group in the benzene ring constituting the diamine compound is not limited, and the amine group is the third or fourth position for the nitrogen atom on Cy, and the nitrogen bonded to Q ₁ and R _{1 is} bonded. It is preferable that the atom is at the position of the third or fourth position, and the nitrogen atom on Cy is the fourth position, and the position where the nitrogen atom bonded to Q ₁ and R ₁ is the fourth position is preferable.

The diamine compound represented by the above formula (1) of the present invention is preferably a structure of the following formula (2).

In the formula (2), R ₁ is a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group. R ₂ is a hydrogen atom or a methyl group. Q ₁ is a linear alkyl group having 1 to 5 carbon atoms.

Specific examples shown in the above formula (2) include those represented by the following formulas (2-1) to (2-10). For the formula below, Boc represents a tert-butoxycarbonyl group.

The specific diamine of the above formula (1) used in the liquid crystal alignment agent of the present invention is preferably 30 mol% or more based on the aromatic tetracarboxylic dianhydride used in the liquid crystal alignment agent of the present invention.

The method for producing the diamine compound of the formula (1) of the present invention is not particularly limited, and a preferred method can be produced by the following method of [1] or [2]. Made.

System of law [1]

The following dinitrogen (3-3) can be produced by reacting 2 equivalents or more of the nitro compound (3-1) with the aliphatic amine compound (3-2). Further, if necessary, a monovalent organic group derived from R ₁ is introduced, and then the desired diamine can be obtained by reducing the nitro group. These nitro compound (3-1) and aliphatic amine compound (3-2) can be obtained by means of a vending product.

In (3-1), X represents a halogen atom which is an F, Cl, Br or I atom. R ₂ is a monovalent organic group, q is an integer of 0 to 4, and when q is 2 or more, a plurality of R ₂ independently have the above definition.

X is F or Cl, and if the NO ₂ group is at the 2nd or 4th position for X, the halogenated aryl group is reacted with the aliphatic amine compound in the presence of a suitable base to obtain a dinitro group (3-3). . As the base to be used, for example, an inorganic salt group such as sodium hydrogencarbonate, potassium hydrogencarbonate, potassium citrate, sodium carbonate, potassium carbonate, lithium carbonate or cesium carbonate, trimethylamine, triethylamine or tripropylamine can be used. An amine such as triisopropylamine, tributylamine, diisopropylethylamine, pyridine, quinoline or collidine or a base such as sodium hydride or potassium hydride.

The solvent may be used as a solvent which does not react with the raw material, and an aprotic polar organic solvent (DMF, DMSO, DMAc, NMP, etc.) or an ether (Et ₂ O, i-Pr ₂ O, TBME, or the like) may be used. CPME, THF, dioxane, etc.), aliphatic hydrocarbons (pentane, hexane, heptane, petroleum ether, etc.), aromatic hydrocarbons (benzene, toluene, xylene, trimethylbenzene, chlorobenzene, dichlorobenzene) , nitrobenzene, tetrahydronaphthalene, etc.), halogen-based hydrocarbons (chloroform, dichloromethane, carbon tetrachloride, dichloroethane, etc.), lower fatty acid esters (methyl acetate, ethyl acetate, acetic acid) Ester, methyl propionate, etc.), nitriles (acetonitrile, propionitrile, butyronitrile, etc.). The solvent may be appropriately selected depending on the easiness of the reaction, and the above-mentioned solvents may be used alone or in combination of two or more. Further, a suitable dehydrating agent or a desiccant may be used as the nonaqueous solvent, as the case may be. The reaction temperature may be arbitrarily selected from the range of -100 ° C to the boiling point of the solvent to be used, preferably in the range of -50 to 150 ° C. The reaction time can be arbitrarily selected from the range of 0.1 to 1000 hours. The product can be purified by recrystallization, distillation, gel column chromatography or the like.

If X is Br or I, the NO ₂ group may be the second, third or fourth position for X, and even if a CN cross-coupling reaction is used in the presence of a suitable metal catalyst, a ligand or a base, two Nitro body. Examples of the metal catalyst include palladium acetate, palladium chloride, palladium chloride-acetonitrile, palladium-activated carbon, bis(dibenzylideneacetone)palladium, and bis(diphenylmethyleneacetone). Dipalladium, bis(acetonitrile) dichloropalladium, bis(benzonitrile)dichloropalladium, CuCl, CuBr, CuI, CuCN, etc., but are not limited thereto. Examples of the ligand include triphenylphosphinylphosphine, tri-o-tolylphosphinic acid, diphenylmethylphosphinylphosphine, phenyldimethylphosphinothine, and 1,2-bis(diphenylphosphine). Ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphine)butane, 1,1'-bis(diphenylphosphino)ferrocene, trimethyl Phosphite, triethyl phosphite, triphenyl phosphite, tri-tert-butyl phosphine, etc., but are not limited thereto. As an example of the base, the aforementioned base can be used. The reaction solvent and the reaction temperature are based on the above description. The product can be purified by recrystallization, distillation, gel column chromatography or the like.

With respect to the formula (4), a monovalent organic group derived from R ₁ may be introduced in the dinitro group (3-3) as necessary.

The introduction of R ₁ is only an amine and a compound which can be reacted, and examples thereof include acid halides, acid anhydrides, isocyanates, epoxy resins, oxetanes, halogenated aryl groups, and halogenated alkyl groups. Further, an alcohol in which a hydroxyl group of an alcohol is substituted with a leaving group such as OMs, OTf or OTs can be used.

The method of introducing a monovalent organic group derived from R ₁ into the NH group is not particularly limited, and a method of reacting the acid halide in the presence of a suitable base can be mentioned. Examples of the acid halide include ethyl chloroform, propionic acid chloride, methyl chloroformate, ethyl chloroformate, n-propyl chloroformate, i-propyl chloroformate, and n-butyl chloroformate. I-butyl chloroformate, t-butyl chloroformate, benzyl chloroformate, and -9-nonyl chloroformate. As an example of the base, the aforementioned base can be used. The reaction solvent and the reaction temperature can be as described above.

The anhydride reaction can be introduced into R ₁ at the NH group. Examples of the acid anhydride include acetic anhydride, propionic anhydride, dimethyl dicarbonate, diethyl dicarbonate, di-tert-butyl dicarbonate, and dicarbonate. Benzyl ester and the like. To promote the reaction, a catalyst can be used, and pyridine, collidine, N,N-dimethyl-4-aminopyridine or the like can be used. The amount of the catalyst is 0.0001 mol to 1 mol for the amount of (3-3) used. The reaction solvent and the reaction temperature are as described above.

The isocyanate reaction can be introduced into R ₁ at the NH group, and examples of the isocyanate include methyl isocyanate, ethyl isocyanate, n-propyl isocyanate, and phenyl isocyanate. The reaction solvent and the reaction temperature are as described above.

In the case where the NH group is reacted with an epoxy compound or an oxetane compound and introduced into R ₁ , examples of the epoxy group or the oxetane group include ethylene oxide and propylene oxide. , 2-butylene oxide, triple stretch methyl oxide, and the like. The reaction solvent and the reaction temperature are based on the above description.

The NH group may be introduced into R ₁ by a halogenated aryl group in the presence of a metal catalyst, a ligand and a base, and examples of the halogenated aryl group include iodobenzene, bromobenzene, chlorobenzene and the like. Examples of the metal catalyst include palladium acetate, palladium chloride, palladium chloride-acetonitrile, palladium-activated carbon, bis(dibenzylideneacetone)palladium, and bis(diphenylmethyleneacetone). Dipalladium, bis(acetonitrile) dichloropalladium, bis(benzonitrile)dichloropalladium, CuCl, CuBr, CuI, CuCN, etc., but are not limited thereto. Examples of the ligand include triphenylphosphinylphosphine, tri-o-tolylphosphinic acid, diphenylmethylphosphinylphosphine, phenyldimethylphosphinothine, and 1,2-bis(diphenylphosphine). Ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphine)butane, 1,1'-bis(diphenylphosphino)ferrocene, trimethyl Phosphite, triethyl phosphite, triphenyl phosphite, tri-tert-butyl phosphine, etc., but are not limited thereto. As an example of the base, the aforementioned base can be used. The reaction solvent and the reaction temperature are based on the above description.

In the presence of a suitable base, the NH group can be introduced into R ₁ by reacting a hydroxyl group of an alcohol with an alcohol substituted with a leaving group such as OMs, OTf or OTs. Examples of the alcohol include methanol, ethanol, and 1-propene. An alcohol or the like can be reacted with methanesulfonyl chloride, trifluoromethanesulfonyl chloride, p-toluenesulfonic acid chloride or the like to obtain an alcohol substituted with a leaving group such as OMs, OTf or OTs. As the base, a base can be used. The reaction solvent and the reaction temperature are as described above.

The NH group can be introduced into R ¹ by reacting a halogenated alkyl group in the presence of a suitable base. Examples of the halogenated alkyl group include methyl iodide, ethyl iodide, n-propyl iodide, methyl bromide, and ethyl group. Bromine, n-propyl bromide, etc. As an example of the base, in addition to the above-mentioned base, metal alkoxides such as potassium third potassium hydride or third sodium butoxide may be used. The reaction solvent and the reaction temperature are based on the above description.

Next, for the formula (5), the obtained dinitrogen (4-1) is obtained. The reduction reaction of the nitro group gives the desired diamine compound (5-1). For this purpose, it may be carried out under a hydrogen atmosphere under normal pressure or under pressure using a palladium carbon powder or a platinum carbon powder.

Further, a metal such as Fe, Sn or Zn or a metal salt thereof may be used as a proton source to carry out a reduction reaction of a nitro group. The metal and metal salts can be used alone or in combination.

As the proton source, an acid such as hydrochloric acid, an ammonium salt such as ammonium chloride, or a protic solvent such as methanol or ethanol can be used.

The solvent can only be used to withstand the environment in a reducing environment, and the aprotic polar organic solvents (DMF, DMSO, DMAc, NMP, etc.) and ethers (Et ₂ O, i-Pr ₂ O, TBME) can be used. , CPME, THF, dioxane, etc.), aliphatic hydrocarbons (pentane, hexane, heptane, petroleum ether, etc.), aromatic hydrocarbons (benzene, toluene, xylene, trimethylbenzene, chlorobenzene, dichloro Benzene, nitrobenzene, tetrahydronaphthalene, etc.), lower fatty acid esters (methyl acetate, ethyl acetate, butyl acetate, methyl propionate, etc.), nitriles (acetonitrile, propionitrile, butyronitrile, etc.), alcohol These solvents of the type (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, etc.) can be appropriately selected in consideration of easiness of the reaction, etc., and the above solvents can be used alone or in combination. 2 or more types. Further, a suitable dehydrating agent or a desiccant may be used as the nonaqueous solvent, as the case may be. The reaction temperature may be selected from any of a range of from -100 ° C to the boiling point of the solvent to be used, preferably from -50 to 150 ° C. The reaction time can be arbitrarily selected in 0.1 to 1000 hours. The product can be purified by recrystallization, distillation, gel column chromatography, activated carbon or the like.

System of law [2]

The intermediate (6-3 or 6-4) is obtained by reacting a nitro compound (3-1 or 6-1) with an aliphatic amine compound (6-2) protected with a protecting group. After the subsequent deprotection, the following dinitrogen (8-1 or 8-2) can be obtained by reacting the nitro compound (3-1 or 6-1). Further, if necessary, a divalent organic group is introduced into R ₁ by the same method as in the production method [1], and then the desired diamine can be obtained by reducing the nitro group.

These dinitro compounds (6-1) and the amine compound (6-2) protected by a protective group can be easily obtained from a commercial product.

In the formula (6), X, R ₂ and q are as described above, and R ₃ is a monovalent organic group, and r is each an integer of 0 to 4. When r is 2 or more, a plurality of R ₃ independently have the above definition.

Pro represents a protecting group which may be an ethyl fluorenyl group, a trifluoroethenyl group, a neopentyl group, a tert-butoxycarbonyl group, an ethoxycarbonyl group, an isopropoxycarbonyl group, a 2,2,2-trichloroethoxy group. Carbocarbonyl, benzyloxycarbonyl, trimethylsulfonyl, triethylsulfonyl, dimethylphenylsulfonyl, tert-butyldimethylhydrazino, tert-butyldiethylhydrazino, 9 - mercaptomethyloxycarbonyl, o-xylylene, allyloxycarbonyl, p-toluenesulfonyl, o-nitrophenylsulfonyl and the like.

The nitro compound (6-3 or 6-4) is synthesized by using one equivalent or more of a nitro compound (3-1 or 6-1), and can be carried out in the same manner as in the formula (3) of the production method [1]. . The protecting group is preferably one which is not deprotected under alkali conditions, and a tert-butoxycarbonyl group is preferred from the viewpoint of easiness of deprotection after the reaction and availability.

In the formula (7), for the nitro compound (6-3 or 6-4), the intermediate (7-1 or 7-2) can be obtained by deprotection.

The deprotection method as the protective group is not particularly limited, and may be neutralized in the presence of an acid or a base after hydrolysis to obtain a desired product. Examples of the acid to be used include inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, and hydrobromic acid; and organic acids such as formic acid, acetic acid, oxalic acid, and trifluoroacetic acid. Examples of the base to be used include hydrogen peroxide. Inorganic base of sodium, sodium hydrogencarbonate, potassium hydrogencarbonate, potassium citrate, sodium carbonate, potassium carbonate, lithium carbonate, cesium carbonate, etc., trimethylamine, triethylamine, tripropylamine, triisopropylamine , organic amines such as tributylamine, diisopropylethylamine, pyridine, quinoline, and collidine. Further, deprotection can be carried out using a Lewis oxide such as aluminum chloride or a trifluoroborane diethyl ether complex. However, the debenzylation reaction in a hydrogen atmosphere is not preferable because of a reduction reaction with an amine of an aromatic nitro group.

The solvent can be used only as a solvent that does not interfere with hydrolysis. Aprotic polar organic solvents (DMF, DMSO, DMAc, NMP, etc.), ethers (Et ₂ O, i-Pr ₂ O, TBME, CPME can be used). , THF, dioxane, etc.), aliphatic hydrocarbons (pentane, hexane, heptane, petroleum ether, etc.), aromatic hydrocarbons (benzene, toluene, xylene, trimethylbenzene, chlorobenzene, dichlorobenzene, Nitrobenzene, tetrahydronaphthalene, etc.), halogen hydrocarbons (chloroform, dichloromethane, carbon tetrachloride, dichloroethane, etc.), lower fatty acid esters (methyl acetate, ethyl acetate, butyl acetate) , methyl propionate, etc.), nitriles (acetonitrile, propionitrile, butyronitrile, etc.), alcohols (methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, etc.) or water. These solvents are appropriately selected in consideration of the easiness of the reaction, and the above-mentioned solvents may be used singly or in combination of two or more. A suitable dehydrating agent or a desiccant is used as a nonaqueous solvent in consideration of the use of Lewis acid or the like. The reaction temperature may be selected from the range of -100 ° C to the boiling point of the solvent to be used, preferably in the range of -50 to 150 ° C. The reaction time can be arbitrarily selected from the range of 0.1 to 1000 hours. The product can be purified by recrystallization, distillation, gel column chromatography or the like.

For the deprotected nitro group (7-1 or 7-2), 1 equivalent or more of the nitro compound (3-1 or 6-1) can be used, and the above formula (3) of the method [1] can be used. The dinitro group (8-1 or 8-2) was obtained in the same manner.

The dinitrogen (8-1 or 8-2) obtained may be introduced into R ₁ as necessary, and the desired diamine may be obtained by reducing the nitro group under the same reaction conditions as in the above formula (4). . The method for reducing the dinitro group can also be carried out by the same reaction conditions as in the above formula (5).

<Other diamines>

In the range in which the polyamic acid used in the liquid crystal alignment agent of the present invention is synthesized, the other diamine compound can be used in addition to the above specific diamine, within the range not impairing the effects of the present invention. Specific examples of the other diamine compounds below can be mentioned.

P-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylene Amine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-di Aminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-Diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diamine Base phenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 3,3'- Trifluoromethyl-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diamine linkage Phenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodi Phenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diamine Diphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'- Sulfonyldiphenylamine, 3,3'-sulfonyldiphenylamine, bis(4-aminophenyl)decane, bis(3-aminophenyl)decane, dimethyl-bis(4-aminobenzene) Base) decane, dimethyl-bis(3-aminophenyl)decane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 4,4'-diaminodiphenyl Amine, 3,3'-diaminodiphenylamine, 3,4'- Diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, 4,4'-diaminobenzophenone, 3,3 '-Diaminobenzophenone, 3,4'-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2'-diaminobenzophenone, 2,3'- Diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diamine Naphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 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-bis(3- Aminophenyl)butane, bis(3,5-diethyl-4-aminophenyl)methane, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4- Aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene, 1,3-bis(4-aminophenethyl)urea, N-methyl-2-(4-amine Phenyl)ethylamine, 4,4'-[1,4-phenylenebis(methyl)diphenylamine, 4,4'-[1,3-phenylenebis(methyl)diphenylamine, 3,4' -[1,4-phenylene d-bis(methyl)diphenylamine, 3,4'-[1,3-phenylenebis(methyl)diphenylamine, 3,3'-[1 , 4-phenylene bis(methyl)diphenylamine, 3,3'-[1,3-phenylenebis(methyl)diphenylamine, 1,4-phenylene bis[(4) -aminophenyl)methanone], 1,4-phenylene bis[(3-aminophenyl)methanone], 1,3-phenylene bis[(4-aminophenyl)methanone ], 1,3-phenylene bis[(3-aminophenyl)methanone], 1,4-phenylene bis(4-aminobenzoate), 1,4-phenylene double (3-amino benzoate), 1,3-phenylene bis(4-aminobenzoate), 1,3-phenylene bis(3-aminobenzoate), double (4-Aminophenyl)ethylene terephthalate, bis(3-aminophenyl)ethylene terephthalate, bis(4-aminophenyl)isophthalate , bis(3-aminophenyl)isophthalate, N,N'-(1,4-phenylene)bis(4-aminobenzamide), N,N'-(1 , 3-phenylene) bis(4-aminobenzamide), N,N'-(1,4-phenylene)bis(3-aminobenzamide), N,N'- (1,3-phenylene) bis(3-aminobenzamide) , N,N'-bis(4-aminophenyl)terephthalamide, N,N'-bis(3-aminophenyl)terephthalamide, N,N'-double ( 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'-double [ 4-(4-Aminophenoxy)phenyl]hexafluoropropane, 2,2'-bis(4-aminophenyl)hexafluoropropane, 2,2'-bis(3-aminophenyl) Hexafluoropropane, 2,2'-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2'-bis(4-aminophenyl)propane, 2,2'-bis ( 3-aminophenyl)propane, 2,2'-bis(3-amino-4-methylphenyl)propane, bis(4-aminophenoxy)methane, 1,2-bis(4- Aminophenoxy)ethane, 1,2-bis(3-aminophenoxy) Ethane, 1,3-bis(4-aminophenoxy)propane, 1,3-bis(3-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butyl Alkane, 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-(4-aminophenoxy) Heptane, 1,7-(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) Mono-, 1,12-(4-aminophenoxy)dodecane, 1,12-(3-aminophenoxy)dodecane, bis(4-aminocyclohexyl)methane, bis ( 4-amino-3-methylcyclohexyl)methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diamino Hexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminodecane, 1,10-diaminodecane, 1,11-diamine Undecane, 1,12-diaminododecane Etc. Among them, bis(4-aminophenoxy)methane, 1,2-bis(4-aminophenoxy)ethane, 1,3-bis(4-aminobenzene) from the viewpoint of good orientation and the like Oxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,6-bis(4-aminobenzene Oxy)hexane, 1,7-(4-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,9-bis(4-aminobenzene Oxy) decane, 1,9-bis(3-aminophenoxy)decane, 1,3-bis(4-aminophenethyl)urea, N-methyl-2-(4-amine Phenylphenyl)ethylamine is preferred.

The other diamine compounds mentioned above are combined with the volume resistivity, the friction resistance, the ion density characteristics, and the like when used as a liquid crystal alignment film. The characteristics such as the over-rate, the liquid crystal alignment property, the voltage-holding property, and the accumulated electric charge can be used in one type or in a mixture of two or more types.

<Synthesis of polyaminic acid>

When polylysine used in the liquid crystal alignment agent of the present invention is obtained by a reaction of a tetracarboxylic dianhydride with a diamine, a method in which a tetracarboxylic dianhydride and a diamine are mixed and reacted in an organic solvent is simple. .

The organic solvent used in the above reaction is not particularly limited as long as it is a polylysine which can be produced by dissolving. To give a specific example, N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-methylhexene are mentioned. Guanidine, dimethyl hydrazine, tetramethyl urea, pyridine, dimethyl hydrazine, hexamethylarylene, γ-butyrolactone and the like. These can be used alone or in combination. Further, even if it is a solvent which does not dissolve in polylysine, it can be used after being mixed with the above solvent in the range in which the produced polyamic acid is not precipitated. Further, since the water in the organic solvent hinders the polymerization reaction and becomes a cause of the polyamic acid produced by the hydrolysis, it is preferred that the organic solvent be dried as described above.

A method of mixing a tetracarboxylic dianhydride component and a diamine component in an organic solvent, and adding a tetracarboxylic dianhydride component directly after stirring a solution in which a diamine component is dispersed or dissolved in an organic solvent, or a method of dispersing or dissolving in an organic solvent, a method of dispersing or dissolving a solution of a tetracarboxylic dianhydride component in an organic solvent, and a method of mutually adding a tetracarboxylic dianhydride component and a diamine component Methods, etc., any of these methods can be used in the present invention. Also, if the tetracarboxylic dianhydride is When the component or the diamine component is formed of a plurality of compounds, the plurality of components may be reacted in a state of being mixed in advance, or may be reacted in order.

The temperature at which the tetracarboxylic dianhydride component and the diamine component are reacted in an organic solvent is usually 0 to 150 ° C, preferably 5 to 100 ° C, preferably 10 to 80 ° C. The higher the temperature, the earlier the polymerization reaction ends, but when it is too high, a polymer having a high molecular weight cannot be obtained. Further, the reaction can be carried out at any concentration. However, when the concentration is too low, it is difficult to obtain a polymer having a high molecular weight. When the concentration is too high, the viscosity of the reaction liquid is too high and it becomes difficult to uniformly stir, so that the weight is 1 to 50. % is preferably, preferably 5 to 30% by weight. The initial stage of the reaction is carried out at a high concentration, and thereafter an organic solvent can be added.

The ratio of the tetracarboxylic dianhydride component to the polymerization reaction of polylysine: the ratio of the diamine component is preferably 1:0.8 to 1.2 at a molar ratio. Further, since the polyamine acid obtained by using the excess diamine component may cause coloring of the solution to be large, it is only necessary to set the above ratio to 1:0.8 to 1 when the solution is colored. Generally, as the polycondensation reaction proceeds, the closer the molar ratio is to 1:1, the larger the molecular weight of the polylysine becomes. If the molecular weight of the poly-proline is too small, the strength of the coating film obtained may be insufficient. On the contrary, if the molecular weight of the poly-proline is too large, the viscosity of the solution when the liquid crystal alignment agent is used as a coating solution may be changed. If it is too high, the workability at the time of formation of a coating film, and the uniformity of a coating film may worsen.

Further, the polyamino acid has a weight average molecular weight of preferably 5,000 to 300,000, preferably 10,000 to 200,000, and more preferably 2,500 to 150,000, more preferably 5,000 to 100,000.

If you do not want to include the solvent used in the polymerization of poly-proline In the liquid crystal alignment agent of the present invention, unreacted monomer components or impurities may be present in the reaction solution, and in this case, precipitation and recovery of polyamic acid may be carried out. In this method, the polyaminic acid solution is introduced into a weak solvent that is being stirred, and the precipitation recovery method is simple. The weak solvent used for precipitation recovery of poly-proline is not particularly limited, and examples thereof include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, and ethanol. , toluene, benzene, etc. The precipitated polylysine is filtered by being applied to a weak solvent. After washing and recovering, it can be made into a powder under normal pressure or reduced pressure at normal temperature or by heating. The powder is further dissolved in a good solvent, and the polyprene acid can be purified by repeating the reprecipitation operation 2 to 10 times. In the case of a single precipitation recovery operation, if the impurities cannot be removed, the purification step is preferably carried out. When a weak solvent of three or more types, such as an alcohol, a ketone, and a hydrocarbon, is used as a weak solvent at this time, it is preferable to improve the purification efficiency in one layer. The above precipitation recovery and purification operation can also be carried out in the same manner as in the synthesis of the polyimine described later.

When the polyamic acid is partially or wholly imidized, the production method is not particularly limited, but the reaction of the tetracarboxylic dianhydride and the polyamine of the diamine can be directly imidized in a solution. At this time, in order to convert a part or all of the polyamic acid into a polyimine, a method of dehydrating and ring-closing by heating or a chemical ring closure using a known dehydration ring-closing catalyst is employed. In the method of heating, it may be selected from 100 ° C to 300 ° C, preferably any temperature selected from 120 ° C to 250 ° C. In the chemically closed-loop method, for example, pyridine, triethylamine or the like is used in the presence of acetic anhydride or the like, and the temperature at this time may be selected from any temperature of from -20 ° C to 200 ° C.

<Liquid alignment agent>

The liquid crystal alignment agent of the present invention is a coating liquid used for forming a liquid crystal alignment film, and the resin component used to form the resin film is a solution dissolved in an organic solvent. The resin component is a resin component containing at least one of the polyamic acid and the polyimine obtained by imidization of the oxime. In this case, the content of the resin component is preferably from 1% by mass to 20% by mass, preferably from 1.5% by mass to 15% by mass, particularly preferably from 2% by mass to 10% by mass.

In the liquid crystal alignment agent of the present invention, the resin component may be the polyaminic acid of the present invention and the polyimine obtained by imidization of the oxime, or may be mixed with other polymers. In this case, the content of the polyamic acid of the present invention and the polymer other than the polyimine obtained by imidization of the resin component is 0.5% by mass to 95% by mass, preferably 1% by mass. % to 90% by mass.

Examples of the other polymer include polylysine of the present invention, polyglycine other than the polyimine obtained by imidization of the ruthenium, and polyimine obtained by imidization of the ruthenium. Wait.

The organic solvent used in the liquid crystal alignment agent of the present invention is not particularly limited as long as it is an organic solvent which can be dissolved by the resin component. Specific examples of this can be exemplified below.

N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone , N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl hydrazine, tetramethyl urea, pyridine, dimethyl hydrazine, hexamethylarylene, γ-butyrolactone, 1,3 - Dimethyl-imidazolidinone, ethyl amyl ketone, methyl decyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, ethyl ethyl carbonate, Propyl carbonate, diglyme, 4-hydroxy-4-methyl-2-pentanone, and the like. These can be used singly or in combination.

The liquid crystal alignment agent of the present invention may contain components other than the above. In this example, there is a solvent which improves film thickness uniformity or surface smoothness when a liquid crystal alignment agent is applied, or a compound which improves adhesion of a compound, a liquid crystal alignment film, and a substrate.

Specific examples of the solvent (weak solvent) for improving the uniformity of the film thickness or the surface smoothness include the following.

Examples thereof include isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, and ethyl cellosolve acetate. Butyl carbitol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, Propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, two Ethylene 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, ethyl isobutyl ether, diisobutylene, pentyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methyl cyclohexene, propyl ether, dihexyl ether, 1 -hexanol, n-hexane, n-pentane , n-octane, two Ethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, 3-methoxypropionic acid Methyl ester, methyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate , 3-methoxypropionic acid butyl ester, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy- 2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, A solvent having a low surface tension such as 2-(2-ethoxypropoxy)propanol, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate or isoamyl lactate.

These weak solvents can be used in one type or in a plurality of types. When the solvent is used, it is preferably from 5 to 80% by mass, preferably from 15 to 60% by mass, based on the total of the solvent contained in the liquid crystal alignment agent.

Examples of the compound for improving the uniformity of the film thickness or the surface smoothness include a fluorine-based surfactant, a polyfluorene-based surfactant, and a nonionic surfactant.

More specifically, for example, EFTOPEF301, EF303, EF352 (manufactured by Tochem Products), Megafac F171, F173, R-30 (manufactured by Dainippon Ink Co., Ltd.), FLUORADFC430, FC431 (manufactured by Sumitomo 3M Co., Ltd.), Asahi Guard AG710, and Surflon S- 382, SC101, SC102, SC103, SC104, SC105, SC106 (made by Asahi Glass Co., Ltd.). The use ratio of the surfactant is preferably 0.01 to 2 parts by mass, preferably 0.01 to 1 part by mass, per 100 parts by mass of the resin component contained in the liquid crystal alignment agent.

Specific examples of the compound which improves the adhesion between the liquid crystal alignment film and the substrate include a compound containing a functional decane or a compound containing an epoxy group.

Examples thereof include 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, and 2-aminopropyltriethoxydecane. N-(2-Aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxydecane, 3-urea Propyltrimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-ethoxycarbonyl-3-aminopropyltri Ethoxy decane, N-triethoxymercaptopropyltriethylamine, N-trimethoxydecylpropyltriethylamine, 10-trimethoxyindolyl-1,4, 7-triazadecane, 10-triethoxyindolyl-1,4,7-triazadecane, 9-trimethoxyindolyl-3,6-diazaindolyl acetate, 9-triethoxyindolyl-3,6-diazaindolyl acetate, N-benzyl-3-aminopropyltrimethoxydecane, N-benzyl-3-aminopropyl Triethoxy decane, N-phenyl-3-aminopropyltrimethoxydecane, N-phenyl-3-aminopropyltriethoxydecane, N-bis(oxyethyl)- 3-aminopropyltrimethoxydecane, N-bis(oxyethyl)-3-aminopropyl Triethoxydecane, 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropyltriethoxydecane, 3-glycidoxypropylmethyldimethoxy Decane, 3-glycidoxypropylmethyldiethoxydecane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl Ethyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2- Dibromo neopentyl 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, 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 is preferably 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, per 100 parts by mass of the resin component contained in the liquid crystal alignment agent. When the amount of use is less than 0.1 part by mass, the adhesion improving effect cannot be expected, and when it is more than 30 parts by mass, the alignment of the liquid crystal may be deteriorated.

In addition to the above, the liquid crystal alignment agent of the present invention may be added as a dielectric or in order to change the electrical properties such as the dielectric constant or the conductivity of the liquid crystal alignment film without impairing the effects of the present invention. A conductive material is a crosslinkable compound for the purpose of improving film hardness or density when used as a liquid crystal alignment film.

The liquid crystal alignment agent of the present invention obtained as described above is applied to a substrate after being filtered, dried, and calcined to obtain a coating film, and the coating film surface is subjected to alignment treatment such as rubbing or light irradiation. Can be used as a liquid crystal alignment film.

In this case, the substrate to be used is not particularly limited, and a plastic substrate such as a glass substrate, an acrylic substrate or a polycarbonate substrate can be used, and an ITO electrode to be driven by a liquid crystal can be used. The viewpoint of simplifying the process is preferable in the case of forming the substrate. Further, in the reflective liquid crystal display device, an opaque substance such as a germanium wafer may be used as the single-sided substrate, and a material that reflects light such as aluminum may be used as the electrode.

Examples of the coating method of the liquid crystal alignment agent include a spin coating method, a printing method, an inkjet method, and the like. However, industrial transfer printing methods are widely used from the viewpoint of productivity, and the present invention is widely used. Liquid crystal alignment agents are also suitable.

Although the drying step after the application of the liquid crystal alignment agent is not an unnecessary process, the time from the application to the completion of the baking is not constant depending on the substrate, or when the baking is not immediately performed after the application, it is preferred to include the drying step. This drying is only required to evaporate the solvent to the extent that the shape of the coating film is not deformed when the substrate is conveyed or the like, and the drying means is not particularly limited. To cite a specific example of 50 to 150 ° C, it is preferably carried out on a hot plate at 80 to 120 ° C for 0.5 to 30 minutes, preferably for 1 to 5 minutes.

The firing of the liquid crystal alignment agent can be carried out at any temperature of 100 to 350 ° C, preferably 150 ° C to 300 ° C, more preferably 200 ° C to 250 ° C. When the polyimine precursor is contained in the liquid crystal alignment agent, the conversion rate from the polyimide precursor to the polyimide may be changed by the firing temperature, and the liquid crystal alignment agent of the present invention does not have to reach 100. % 醯 imidization. However, it is preferable that the sealant hardening or the like which is considered to be necessary in the liquid crystal cell production step is baked at a high temperature higher than the heat treatment temperature by 10 ° C or higher.

When the thickness of the coating film after firing is too thick, it is disadvantageous in terms of the power consumption of the liquid crystal display element. If it is too thin, the reliability of the liquid crystal display element may be lowered, so that it is 5~ 300 nm, preferably 10 to 100 nm.

<Liquid crystal display element>

In the liquid crystal display device of the present invention, a liquid crystal cell is produced by a known method from the liquid crystal alignment agent of the present invention, and a liquid crystal cell is produced by a known method. For an example of the fabrication of the liquid crystal cell, generally, a pair of substrates on which the liquid crystal alignment film is formed is sandwiched by a spacer of usually 1 to 30 μm, preferably 2 to 10 μm, and the preferred rubbing direction is 0 to 270. At any angle of °, the surrounding is fixed with a sealant and injected into the liquid crystal for sealing. In the rubbing treatment for the liquid crystal alignment film, an existing friction device can be used. Examples of the material of the rubbing cloth at this time include cotton, rayon, nylon, and the like. The liquid crystal sealing method is not particularly limited, and a vacuum method in which a liquid crystal cell is produced under reduced pressure, a vacuum method in which a liquid crystal is injected, and a dropping method in which a liquid crystal is dropped and sealed is exemplified.

As described above, the liquid crystal display element produced by using the liquid crystal alignment agent of the present invention has excellent liquid crystal alignment property, orientation adjustment force, and excellent electrical characteristics, and thus can be used as a liquid crystal display device which is difficult to cause contrast reduction or imprinting. Among these liquid crystal display elements, a liquid crystal display element of a lateral electric field type which does not easily cause an imprint from the directional adjustment force is particularly preferable.

[Examples]

The invention is further illustrated by the following examples, but it is not intended that the invention be construed as limited.

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

X-2: pyromellitic dianhydride

X-3: 3,3',4,4'-biphenyltetracarboxylic dianhydride

Y-1: 1,3-bis(4-aminophenethyl)urea

Y-2: 4-(2-(methylamino)ethyl)aniline

Y-3: 4,4'-diaminodiphenylamine

Y-4: bis(4-aminophenoxy)methane

DA-1: a compound represented by the following structural formula

Each measurement method is shown below.

[viscosity]

For the synthesis example, the viscosity of the polyaminic acid solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) to a sample volume of 1.1 mL. The tapered rotor TE-1 (1°34', R24) was measured at a temperature of 25 °C.

[solid content concentration]

In the synthesis example, the solid content concentration of the polyaminic acid solution was calculated as follows.

Approximately 1.1 g of the solution was placed in an aluminum cup No. 2 (manufactured by AS ONE) equipped with a handle, and heated in an oven DNF400 (manufactured by Yamato Co., Ltd.) at 200 ° C for 2 hours, and then left at room temperature for 5 minutes. Weigh the weight of the solid content remaining in the aluminum cup. The solid content concentration was calculated from the weight of the solid component and the weight value of the original solution.

[molecular weight]

The molecular weight of the polyaminic acid solution is measured by a GPC (normal temperature gel permeation chromatography) apparatus, and the number average molecular weight (hereinafter also referred to as Mn) and the weight average molecular weight in terms of polyethylene glycol and polyethylene oxide are calculated. (hereinafter also referred to as Mw).

GPC device: (share) made by Shodex (GPC-101)

Pipe column: made by Shodex (KD803, inline of KD805)

Column temperature: 50 ° C

Dissolution: N,N-dimethylformamide (as additive, lithium bromide-hydrate (LiBr.H ₂ O) 30 mmol/L, phosphoric acid. anhydrous crystal (o-phosphoric acid) 30 mmol/L, tetrahydrofuran (THF) 10 ml /L)

Flow rate: 1.0ml/min

Standard curve preparation standard sample: TSK standard manufactured by Tosoh Corporation Quasi-polyethylene oxide (weight average molecular weight (Mw) of about 900,000, 150,000, 100,000, 30,000), and polyethylene glycol manufactured by Polymer Laboratories (absorption peak molecular weight (Mp) of about 12,000, 4,000, 1,000) . In the measurement, it is necessary to avoid the overlap of the absorption peaks, and to mix four samples of 900,000, 100,000, 12,000, and 1,000 samples, and two samples of three types of samples of 150,000, 30,000, and 4,000, for individual measurement.

[Production of liquid crystal cell]

A liquid crystal cell having a structure of an FFS liquid crystal display element was produced.

First, prepare a substrate with an electrode attached. The substrate was a glass substrate having a size of 30 mm × 35 mm and a thickness of 0.7 mm, and a counter electrode was formed as a first layer on the substrate to form a solid pattern IZO electrode. As the second layer on the counter electrode of the first layer, a SiN (tantalum nitride) film formed by a CVD method is formed. The thickness of the SiN film of the second layer was 500 nm, which was used as a function of the interlayer insulating film. On the SiN film of the second layer, a comb-shaped pixel electrode formed by patterning the IZO film as the third layer is disposed, and two kinds of pixels of the first pixel and the second pixel are formed. The size of each pixel is 10 mm in length and 5 mm in width. At this time, the counter electrode of the first layer and the pixel electrode of the third layer are electrically insulated by the action of the SiN film of the second layer.

The pixel electrode of the third layer has a comb-like shape in which the electrode elements of the "ㄑ" shape in which the central portion is curved are arranged in plural. The width of each electrode element in the lateral direction is 3 μm. The interval between the electrode elements was 6 μm. Since the pixel elements forming the respective pixels are formed by a plurality of electrode elements having a "ㄑ" shape in which the central portion is curved, the shape of each pixel is not rectangular, and is similar to the electrode element in the central portion. For bending, it has a "ㄑ" shape similar to a thick word. Each of the pixels divides the curved portion of each center into upper and lower portions as a boundary, 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 these pixel electrodes are formed is different. In other words, when the rubbing direction of the liquid crystal alignment film to be described later is used as a reference, the electrode element of the pixel electrode is formed at an angle of +10° (clockwise direction) in the first region of the pixel, and is drawn in the second region of the pixel. The electrode elements of the element electrodes are formed at an angle of -10° (clockwise). In other words, in the first region and the second region of each pixel, the liquid crystal is caused by the voltage applied between the pixel electrode and the counter electrode, and the liquid crystal is rotated in the plane of the substrate (plane. switch). Reverse each other.

Next, the obtained liquid crystal alignment agent was filtered through a 1.0 μm filter, and then coated on the prepared electrode-attached substrate by spin coating. After drying on a hot plate at 100 ° C for 100 seconds, the film was fired in a hot air circulating oven at 230 ° C for 20 minutes to obtain a polyimide film having a film thickness of 60 nm. The polyimide film was rubbed with a rayon cloth (roller diameter: 120 mm, number of rotations of the drum: 500 rpm, moving speed: 30 mm/sec, pressing length: 0.3 mm, rubbing direction: combing the third layer of IZO) After the tooth electrode is inclined by 10°, the ultrasonic wave is irradiated for 1 minute in a 3/7 mixed solvent of isopropyl alcohol and pure water, and the water is removed by blowing. Thereafter, the substrate was dried at 80 ° C for 15 minutes to obtain a substrate with a liquid crystal alignment film. Further, as a counter substrate, a polyimide substrate having a columnar spacer having a height of 4 μm in which an ITO electrode was formed was formed in the same manner as described above, and the alignment treatment was carried out in the same manner as described above. A substrate with a liquid crystal alignment film. These two substrates with a liquid crystal alignment film are used as one set, and the sealant is printed on the substrate so as to remain in the liquid crystal injection port, and the other substrate faces the liquid crystal alignment film surface, and the paste is reversed in the rubbing direction. After paralleling, the hardening sealant produced void cells having a cell gap of 4 μm. In the cell, the liquid crystal MLC-2041 (manufactured by Merck & Co., Inc.) (hereinafter generally referred to as liquid crystal) or the liquid crystal is added to the cell, and the sealant STRUCT BONDTM XN-1500T is added (Mitsui Chemical Co., Ltd.) 5 wt% of the company, liquid crystal heated at 50 ° C for 1 hour (hereinafter referred to as sealed contaminated liquid crystal) was injected, and the injection port was sealed to obtain an FFS liquid crystal cell. Thereafter, the obtained liquid crystal cell was heated at 110 ° C for 30 minutes, and left at 23 ° C for one night and used for each evaluation.

[Accumulated charge mitigation characteristics]

The liquid crystal cell (usually using liquid crystal) is placed between two polarizing plates in which the polarizing axis is perpendicular, and the pixel electrode and the counter electrode are short-circuited to have the same potential, and are under the two polarizing plates. The LED backlight is illuminated to adjust the angle of the liquid crystal cell to minimize the brightness of the LED backlight transmitted light measured above the two polarizing plates.

Next, a rectangular wave having a frequency of 30 Hz is applied to the liquid crystal cell, and the V-T characteristic (voltage-transmittance) is measured at a temperature of 23 ° C. Characteristic), an AC voltage having a relative transmittance of 23% was calculated. The AC voltage is suitable for evaluating the residual charge via the brightness because it corresponds to a region where the luminance changes greatly.

Next, after a rectangular wave having a relative transmittance of 23% and a rectangular wave having a frequency of 30 Hz was applied for 5 minutes, a DC voltage of +1.0 V was superimposed and driven for 30 minutes. Thereafter, the DC voltage was cut off, and an AC voltage of 23% with respect to the transmittance was again applied, and only a rectangular wave having a frequency of 30 Hz was applied for 30 minutes.

The faster the accumulated charge is relaxed, and the charge accumulation of the liquid crystal cell when the DC voltage is superposed is also fast, so the relaxation characteristic of the accumulated charge is required to be reduced to 23% in a state in which the relative transmittance after overlapping the DC voltage is 30% or more. Time to make an assessment. The shorter the time, the better the relaxation characteristic of the accumulated charge is evaluated. It is ○ when it is less than 30 minutes, and it is × when it is 30 minutes or more.

[Liquid alignment]

The above liquid crystal cell (usually liquid crystal) was applied at a constant temperature of 60 ° C for a relative transmittance of 100% at a frequency of 30 Hz, and an alternating voltage was applied for 150 hours.

Thereafter, a short-circuit state between the pixel electrode of the liquid crystal cell and the counter electrode is caused, and it is left at room temperature for one day.

After being placed, the liquid crystal cell is disposed between two polarizing plates that are disposed perpendicular to the polarizing axis, and the backlight is turned on in a state where the voltage is not applied, and the arrangement angle of the liquid crystal cell is adjusted to the minimum of the transmitted light. And the first The angle of rotation of the 1 pixel from the darkest angle in the second region to the darkest angle in the first region is calculated as the angle ΔAngle. Similarly, in the second pixel, the second region and the first region are compared, and the same angle ΔAngle is calculated. On the other hand, the average value of the angle ΔAngle value of the first pixel and the second pixel is calculated as the angle ΔAngle of the liquid crystal cell. △ Angle is indicated by ○ when it is less than 0.1°, and is represented by × when it is 0.1° or more.

[Vcom stability under sealed pollution conditions]

The liquid crystal cell (usually using liquid crystal and sealed contaminated liquid crystal) is placed between two polarizing plates in which the polarizing axis is perpendicular, and the pixel electrode and the counter electrode are short-circuited to have the same potential. The LED backlight is irradiated from the lower surface of the two polarizing plates, and the angle of the liquid crystal cell is adjusted to minimize the brightness of the LED backlight transmitted through the two polarizing plates.

Next, a V-T bend (voltage-transmittance curve) was measured while applying an AC voltage having a frequency of 30 Hz to the liquid crystal cell, and an AC voltage having a transmittance of 23% or 100% was calculated as a drive voltage. The liquid crystal cell was heated to 60 ° C, and a rectangular wave of 20 mV at a frequency of 1 kHz was applied for 30 minutes.

Thereafter, the relative transmittance of 30 minutes was added to become an AC drive of 100%. The minimum offset voltage value was measured every three minutes, and the amount of change from the start of the measurement to 30 minutes was calculated. The difference between the minimum offset voltage value and the minimum offset voltage value after 30 minutes in the cell using the sealed contamination liquid crystal is usually taken as ΔVcom after 30 minutes in the cell using the liquid crystal. △Vcom is not up to When it is 50 mV, it is represented by ○, and when it is 50 mV or more, it is represented by ×.

[Synthesis example]

Synthesis of (DA-1)

In a 4-neck flask under nitrogen atmosphere, dimethylformamide (390 g), 4-fluoronitrobenzene (65.0 g, 0.461 mol), 4-aminomethylpiperidine (25.0 g, 0.219 mol) were added. Potassium carbonate (90.9 g, 0.658 mol) was reacted at 60 °C. After heating and stirring for 22 hours, the disappearance of the intermediate was confirmed by HPLC, and then potassium carbonate was removed by filtration, and potassium carbonate was washed twice with 250 g of dimethylformamide. The obtained solution was distilled under reduced pressure to a content of 295 g, and 1.50 kg of water was added thereto, and after the compound (11) was precipitated, the precipitate was collected by filtration and dried to give a crude compound (11). The obtained crude product was purified by recrystallization from tetrahydrofuran to afford compound (11) (58.8 g, 0.165 mol, yield: 75.3%).

The structure of the compound (11) was confirmed by ¹ H-NMR analysis to obtain the following spectral data.

¹ H-NMR (DMSO): δ = 8.05-7.98 (m, 4H), 7.41 (t, 1H J = 6.8), 7.02 (d, 2H, J = 9.6), 6.68 (d, 2H, J = 9.2) , 4.09 (d, 2H, J = 13.6), 3.10 (t, 2H, J = 6.0), 2.98 (t, 2H, J = 12.0), 1.91-1.89 (m, 1H), 1.89-1.83 (m, 2H) ), 1.29-1.19 (m, 2H).

Tetrahydrofuran (400 g), compound (11) (20.0 g, 0.0561 mol), N,N-dimethyl-4-aminopyridine (77.4 mg, 0.634 mmol) were placed in a 4-neck flask under nitrogen atmosphere and Heat at 50 °C. A mixed liquid of di-tert-butyl dicarbonate (15.3 g, 0.0699 mol) and 15.0 g of tetrahydrofuran was added dropwise to the solution, and after reacting for 24 hours, it was confirmed by HPLC that the starting material disappeared. After the content was distilled off under reduced pressure, the crystals were recrystallized from toluene, and the precipitated crystals were filtered and dried to give a compound (12) as a yellow solid, yield: 87.3% (22.3 g, 0.0489 mol).

The structure of the compound (12) was confirmed by ¹ H-NMR analysis to obtain the following spectral data.

¹ H-NMR (DMSO): δ = 8.21 (d, 2H, J = 8.8), 8.01 (d, 2H J = 9.2), 7.61 (d, 2H, J = 9.2), 6.98 (d, 2H, J = 9.6), 4.02 (d, 2H, J = 13.6), 3.69 (d, 2H, J = 7.2), 2.91 (t, 2H, J = 11.6), 1.86-1.70 (m, 1H), 1.66 (d, 2H) , J = 11.2), 1.42 (s, 9H), 1.22-1.10 (m, 2H).

Tetrahydrofuran (447 g), compound (12) (22.3 g, 0.0489 mol), and palladium carbon powder (1.16 g) were placed in a 4-neck flask under a nitrogen atmosphere, and replaced with a hydrogen atmosphere at room temperature for 23 hours. Stir. After confirming the disappearance of the starting material by HPLC, the solution obtained by filtering palladium carbon was distilled off under reduced pressure to give a crude material. Chloroform (206 g) was added to the crude product, and after heating at 60 ° C, the liquid separation operation was repeated twice with water (100 g) at 60 °C. Activated carbon (0.754 g) was added to the obtained organic layer and stirred, and then activated carbon was removed by filtration. The content was concentrated, and recrystallized from toluene, followed by drying to obtain (DA-1) of the objective compound as a creamy solid. The yield was 71.3% (13.8 g, 0.0349 mol).

The structure of the compound (DA-1) was confirmed by 1 H-NMR analysis to obtain the following spectral data.

¹ H-NMR (DMSO): δ = 6.83 (d, 2H, J = 8.0), 6.65 (d, 2H J = 8.4), 6.50 (d, 2H, J = 8.4), 6.45 (d, 2H, J = 8.4), 5.05 (br, 2H), 4.54 (br, 2H), 3.41 (d, 2H, J = 6.8), 3.29 (d, 2H, J = 12.4), 2.36 (t, 2H, J = 10.8), 1.64 (d, 2H, J = 11.6), 1.42-1.19 (br, 12H).

(Synthesis Example 1)

(Y-1) 4.18 g (14.0 mmol), (DA-1) 2.38 g (6.0 mmol) were placed in a 100 mL four-necked flask equipped with a stirrer, and N-methyl-2-pyrrolidone 76.7 was added. g, stirring and dissolving while supplying nitrogen gas. While stirring the diamine solution, 4.14 g (19.0 mmol) of (X-2) was added, and 19.2 g of N-methyl-2-pyrrolidone was further added thereto, and the mixture was stirred at 60 ° C for 13 hours under a nitrogen atmosphere. Polylysine solution. The polyamic acid solution has a viscosity of 131 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyamic acid was Mn = 10,600 and Mw = 32,800.

18.1 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stir bar, and 12.1 g of N-methyl-2-pyrrolidone and 10.0 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 4.33 mass% was obtained.

(Synthesis Example 2)

(Y-1) 2.83 g (9.5 mmol), (DA-1) 3.77 g (9.5 mmol) were placed in a 100 mL four-necked flask equipped with a stirrer, and N-methyl-2-pyrrolidone 75.6 was added. g, stirring and dissolving while supplying nitrogen gas. While stirring the diamine solution, (X-2) 3.90 g (17.9 mmol) was added, and then 18.9 g of N-methyl-2-pyrrolidone was added, and the mixture was allowed to stand at 60 ° C for 13 hours under a nitrogen atmosphere. Proline solution. The polyamic acid solution has a viscosity of 99 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyamic acid was Mn = 8,600 and Mw = 26,900.

18.9 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stir bar, and 12.6 g of N-methyl-2-pyrrolidone and 10.5 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 4.51% by mass was obtained.

(Synthesis Example 3)

(Y-1) 1.70 g (5.7 mmol), (DA-1) 5.27 g (13.3 mmol) were placed in a 100 mL four-necked flask equipped with a stirrer, and N-methyl-2-pyrrolidone 78.3 was added. g, stirring and dissolving while supplying nitrogen gas. While stirring the diamine solution, (X-2) 3.94 g (18.1 mmol) was added, and then 19.6 g of N-methyl-2-pyrrolidone was added, and the mixture was obtained at 60 ° C for 13 hours under a nitrogen atmosphere. Proline solution. The polyamic acid solution has a viscosity of 121 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyproline was Mn = 11,200 and Mw = 39,200.

18.1 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stir bar, and 12.1 g of N-methyl-2-pyrrolidone and 10.1 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 3.95 mass% was obtained.

(Synthesis Example 4)

(Y-1) 3.76 g (12.6 mmol), (Y-2) 0.31 g (2.1 mmol), and (DA-1) 2.50 g (6.3 mmol) were placed in a 100 mL four-neck flask equipped with a stirrer. 67.1 g of N-methyl-2-pyrrolidone was added, and the mixture was stirred and dissolved while supplying nitrogen gas. While stirring the diamine solution, (X-1) 2.47 g (12.6 mmol), (X-2) 1.60 g (7.4 mmol), and further added N-methyl-2-pyrrolidone 28.8 g, under nitrogen Under the environment, a polyglycine solution was obtained after stirring at 50 ° C for 12 hours. The polyamic acid solution has a viscosity of 145 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polylysine was Mn = 10,300 and Mw = 33,700.

19.1 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stirrer, and 11.5 g of N-methyl-2-pyrrolidone and 7.6 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 4.12% by mass was obtained.

(Synthesis Example 5)

(Y-1) 6.27 g (21.0 mmol), (Y-2) 2.10 g (14.0 mmol), and N-methyl-2-pyrrolidone 67.5 g were placed in a 100 mL four-neck flask equipped with a stir bar. The mixture was stirred and dissolved while feeding nitrogen gas. While stirring the diamine solution, (X-1) 6.52 g (33.3 mmol) was added, and 16.9 g of N-methyl-2-pyrrolidone was further added, and the mixture was stirred at 23 ° C for 4 hours under a nitrogen atmosphere. Polylysine solution. The polyamic acid solution has a viscosity of 740 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyamic acid was Mn = 11,100 and Mw = 33,500.

18.6 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stir bar, and 19.8 g of N-methyl-2-pyrrolidone and 10.3 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 4.08 mass% was obtained.

(Synthesis Example 6)

(Y-1) 10.44 g (35.0 mmol) was placed in a 200 mL four-necked flask equipped with a stirrer, and 103.4 g of N-methyl-2-pyrrolidone was added thereto, and the mixture was stirred and dissolved while supplying nitrogen gas. While stirring the diamine solution, (X-2) 7.18 g (32.9 mmol) was added, and N-methyl-2-pyridyl was further added. 25.8 g of flavonone was stirred at 60 ° C for 8 hours under a nitrogen atmosphere to obtain a polyaminic acid solution. The polyamic acid solution has a viscosity of 300 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyamic acid was Mn = 10,200 and Mw = 29,500.

18.3 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stirrer, and 19.5 g of N-methyl-2-pyrrolidone and 10.2 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 4.25 mass% was obtained.

(Synthesis Example 7)

(Y-3) 2.40 g (12.0 mmol) was placed in a 50 mL four-necked flask equipped with a stirrer, and 29.8 g of N-methyl-2-pyrrolidone was added thereto, and the mixture was stirred and dissolved while supplying nitrogen gas. While stirring the diamine solution, (X-3) 3.41 g (11.6 mmol) was added, and then 12.8 g of N-methyl-2-pyrrolidone was added, and the mixture was stirred at 23 ° C for 25 hours under a nitrogen atmosphere. Polylysine solution. The polyamic acid solution has a viscosity of 550 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polylysine was Mn = 11,200 and Mw = 33,900.

16.2 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stir bar, and 13.0 g of N-methyl-2-pyrrolidone, 0.02 g of LS-4668, and 9.73 g of butyl cellosolve were added, and magnetic stirring was carried out. After stirring for 2 hours, a polyamine acid solution having a solid concentration of 5.00% by mass was obtained.

(Synthesis Example 8)

(Y-4) 8.52 g (37.0 mmol) was placed in a 100 mL four-necked flask equipped with a stirrer, and 112.0 g of N-methyl-2-pyrrolidone was added thereto, and the mixture was stirred and dissolved while supplying nitrogen gas. While stirring the diamine solution, (X-1) 6.89 g (35.2 mmol) was added, and then 27.7 g of N-methyl-2-pyrrolidone was added, and the mixture was stirred at 23 ° C for 5 hours under a nitrogen atmosphere. A polylysine solution was obtained. The polyamic acid solution has a viscosity of 436 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyproline was Mn = 18,400 and Mw = 47,000.

10.3 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask in which a stirrer was placed, and 18.7 g of N-methyl-2-pyrrolidone and 9.68 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 4.00% by mass was obtained.

(Synthesis Example 9)

Into a 500 mL four-necked flask equipped with a stirrer, 23.79 g (60.0 mmol) of (DA-1) was placed, and 300.0 g of N-methyl-2-pyrrolidone was added thereto, and the mixture was stirred and dissolved while supplying nitrogen gas. While stirring the diamine solution, 11.18 g (58.2 mmol) of (X-1) was added, and 14.7 g of N-methyl-2-pyrrolidone was further added thereto, followed by stirring at 23 ° C for 5 hours under a nitrogen atmosphere. Polylysine solution. The polyamic acid solution has a viscosity of 184 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyamic acid was Mn = 11,300 and Mw = 49,600.

19.3 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stir bar, and N-methyl-2-pyrrolidone 11.6 g and butyl group were added. 7.73 g of cellosolve was stirred in a magnetic stirrer for 2 hours to obtain a polyaminic acid solution having a solid concentration of 4.31% by mass.

(Synthesis Example 10)

(Y-1) 5.07 g (17.0 mmol), (DA-1) 1.19 g (3.0 mmol) were placed in a 100 mL four-neck flask equipped with a stirrer, and N-methyl-2-pyrrolidone 74.6 was added. g, stirring and dissolving while supplying nitrogen gas. While stirring the diamine solution, (X-2) 4.10 g (18.8 mmol) was added, and then 18.7 g of N-methyl-2-pyrrolidone was added, and the mixture was obtained at 60 ° C for 13 hours under a nitrogen atmosphere. Proline solution. The polyamic acid solution has a viscosity of 113 mPa at a temperature of 25 ° C. s. Further, the molecular weight of the polyamic acid was Mn = 9,400 and Mw = 28,900.

18.4 g of this polyaminic acid solution was placed in a 100 mL Erlenmeyer flask equipped with a stirrer, and 12.2 g of N-methyl-2-pyrrolidone and 10.2 g of butyl cellosolve were added, and the mixture was stirred for 2 hours with a magnetic stirrer. A polyaminic acid solution having a solid concentration of 4.33 mass% was obtained.

<Example 1>

A liquid crystal cell was produced by using a polyamine acid solution obtained in Synthesis Example 1 and a polyamic acid solution obtained in Synthesis Example 5 using a mixed solution having a solid content of 40:60 by weight.

<Example 2>

The polyaminic acid solution obtained in Synthesis Example 2 was obtained in Synthesis Example 5. The polyamic acid solution was prepared by using a mixed solution having a solid content of 40:60 by weight to prepare a liquid crystal cell.

<Example 3>

A liquid crystal cell was produced by using a polyamine acid solution obtained in Synthesis Example 3 and a polyamic acid solution obtained in Synthesis Example 5 using a mixed solution having a solid content of 40:60 by weight.

<Example 4>

A liquid crystal cell was produced using the polyamic acid solution obtained in Synthesis Example 4.

<Comparative Example 1>

A liquid crystal cell was produced using the polyamic acid solution obtained in Synthesis Example 6.

<Comparative Example 2>

A liquid crystal cell was produced by using a polyamine acid solution obtained in Synthesis Example 6 and a polyamic acid solution obtained in Synthesis Example 5 using a mixed solution having a solid content of 40:60 by weight.

<Comparative Example 3>

A liquid crystal cell was produced using the polyamic acid solution obtained in Synthesis Example 7.

<Comparative Example 4>

A liquid crystal cell was produced using the polyamic acid solution obtained in Synthesis Example 8.

<Comparative Example 5>

A liquid crystal cell was produced using the polyamic acid solution obtained in Synthesis Example 9.

<Comparative Example 6>

A liquid crystal cell was produced by using a polyamine acid solution obtained in Synthesis Example 10 and a polyamic acid solution obtained in Synthesis Example 5 using a mixed solution having a solid content of 40:60 by weight.

Claims (9)

A liquid crystal alignment agent characterized by containing a polymer having a tetracarboxylic dianhydride component containing an aromatic tetracarboxylic dianhydride and a diamine component containing a diamine of the following formula (1) And at least one of the obtained poly-proline and the polyimine obtained by imidization of the hydrazine; R ₁ represents hydrogen or a monovalent organic group, Q ₁ represents an alkylene group having 1 to 5 carbon atoms, and Cy represents an aliphatic group derived from azetidine, pyrrolidine, piperidine or hexamethyleneimine. a divalent group of a heterocyclic ring, a substituent may be bonded to these ring moieties, R ₂ and R ₃ are monovalent organic groups, and q and r are each independently an integer of 0 to 4; however, when the total of q or r is 2 or more A plurality of R ₂ and R ₃ independently have the above definitions. The liquid crystal alignment agent of claim 1, wherein R ₁ is an alkyl group having 1 to 3 carbon atoms, a hydrogen atom or a thermally detachable group substituted by a heat to a hydrogen atom, and each of R ₂ and R _{3 is} independently a hydrogen atom; Methyl, trifluoromethyl, cyano or methoxy. The liquid crystal aligning agent of claim 1 or 2, wherein R ₁ is a linear alkyl group having 1 to 3 carbon atoms, a hydrogen atom or a tert-butoxycarbonyl group, and Cy is a pyrrolidine ring or a piperidine ring. The liquid crystal alignment agent of claim 1, which comprises the diamine compound represented by the following general formula (2); In the formula (2), R ₁ is a hydrogen atom, a methyl group or a tert-butoxycarbonyl group, R ₂ is a hydrogen atom or a methyl group, and Q ₁ is a linear alkylene group having 1 to 5 carbon atoms. The liquid crystal alignment agent of claim 1, wherein the aromatic tetracarboxylic dianhydride is 20 mol% or more of the total tetracarboxylic dianhydride component. The liquid crystal alignment agent of claim 1, wherein the aromatic tetracarboxylic dianhydride is pyromellitic dianhydride. The liquid crystal alignment agent of claim 1, wherein the diamine of the above formula (1) is 30 mol% or more with respect to the aromatic tetracarboxylic dianhydride. A liquid crystal alignment film characterized by using the liquid crystal alignment agent of any one of claims 1 to 7. A liquid crystal display element comprising the liquid crystal alignment film of claim 8.