JP7315907B2 - Diamine and polymer using same - Google Patents

Description

The present invention provides a novel diamine compound (simply referred to as diamine in the present invention) that is useful as a raw material for polymers used in liquid crystal alignment films, and polyamic acids, polyamic acid esters, polyimides, and other polymers obtained using the same. Regarding coalescence.

BACKGROUND ART Liquid crystal display elements have been widely used as display units of personal computers, mobile phones, television receivers, and the like. A lateral electric field method such as a field switching (Fringe Field Switching: hereinafter referred to as FFS) method is known.

In general, the lateral electric field method, in which electrodes are formed only on one side of the substrate and an electric field is applied in the direction parallel to the substrate, has a wider field than the vertical electric field method, in which a voltage is applied to the electrodes formed on the upper and lower substrates to drive the liquid crystal. It is easy to obtain a liquid crystal display device that has viewing angle characteristics and is capable of high-quality display. As a method for aligning liquid crystal in a certain direction, for example, there is a method of forming a polymer film such as polyimide on a substrate and rubbing the surface with a cloth, which is a so-called rubbing treatment.

Conventional problems include improvement of the voltage holding ratio and improvement of charge accumulation due to the DC voltage component applied from the active matrix structure. Accumulation of electric charge in the liquid crystal display element adversely affects the display due to disturbance of the liquid crystal alignment and generation of afterimages, thereby significantly deteriorating the display quality of the liquid crystal display element. Alternatively, if driving is performed in a state in which charges are accumulated, liquid crystal molecules are not normally controlled immediately after driving, resulting in flicker or the like.

Moreover, ion density is mentioned as a property required for the liquid crystal alignment film in order to improve the display quality of the liquid crystal display element. If the ion density is high, the voltage applied to the liquid crystal is lowered, resulting in a decrease in brightness, which may interfere with normal gradation display. Moreover, even if the initial ion density is low, the ion density may become high after the high temperature accelerated test. The deterioration of long-term reliability and the generation of afterimages due to residual charges and ionic impurities degrade the display quality of liquid crystals.

Various proposals have been made for polyimide-based liquid crystal alignment films in order to meet the above demands. For example, as a liquid crystal alignment film for one purpose of shortening the time until afterimages generated by DC voltage disappear, in addition to polyamic acid and imide group-containing polyamic acid, a liquid crystal containing a tertiary amine with a specific structure is used. Those using an aligning agent (see, for example, Patent Document 1) and those using a liquid crystal aligning agent containing a soluble polyimide using a specific diamine compound having a pyridine skeleton or the like as a raw material (see, for example, Patent Document 2). Proposed.

JP-A-9-316200 JP-A-10-104633

Rubbing treatment is widely used industrially as a method for aligning liquid crystals, but depending on the liquid crystal alignment film used, a phenomenon may occur in which the rubbing direction and the alignment direction of liquid crystals do not match, that is, a so-called twist angle occurs. In other words, the horizontal electric field element exhibits black display when no voltage is applied, but due to this phenomenon, the brightness increases even when no voltage is applied, resulting in a decrease in display contrast. there were.

The present inventors have found that it is possible to keep the ion density in the liquid crystal display element low and to relax the accumulated electric charge quickly, and suppress the deviation between the rubbing direction and the alignment direction of the liquid crystal, which is a problem especially in the horizontal electric field driving method. The liquid crystal aligning film which can carry out, the liquid crystal aligning agent from which such a liquid crystal aligning film is obtained, and the liquid crystal display element etc. which contain such a liquid crystal aligning film were provided. An object of the present invention is to provide a novel diamine used in the previously invented liquid crystal aligning agent and a polymer using the same.

As a result of intensive studies to solve the above problems, the present inventors have found that various properties can be improved at the same time by introducing a specific structure into the polymer contained in the liquid crystal aligning agent. completed the invention. The present invention is based on such findings, and has the following gist.

1. A diamine having a structure represented by the following formula (1).

Ｒ^１は水素原子、炭素数１～５の直鎖若しくは分岐してもよいアルキル基又はアリール基を表し、同じマレイミド環上に２つあるＲ^１は互いに同一でも、異なっていてもよく、２つあるＲ^１が一緒になって炭素数３～６のアルキレンを形成してもよく、Ｗ^２は２価の有機基を表し、Ｗ^１は単結合又はカルボニルを表し、Ｌ^１は炭素数１～２０の直鎖状アルキレン基、炭素数３～２０の分岐状アルキレン基、炭素数３～２０の環状アルキレン基、フェニレン基及び複素環基から選ばれる二価の基、又は当該二価の基が複数結合してなる基を表し、フェニレン基及び複素環基はそれぞれ独立にアルキル基、アルコキシ基、ハロアルキル基、ハロアルコキシ基、ハロゲン基及びシアノ基から選ばれる同一又は相異なる１又は複数の置換基で置換されていてもよく、当該二価の基同士の結合は、単結合、エステル結合、アミド結合、ウレア結合、エーテル結合、チオエーテル結合、アミノ結合及びカルボニルから選ばれる少なくとも一種であり、当該二価の基が複数となる場合は、二価の基同士は同一でも異なっていてもよく、上記結合が複数となる場合は、結合同士は同一でも異なっていてもよく、Ｒは水素原子又は一価の有機基を表し、２つあるＲが互いに異なっていてもよく、２つあるＲが一緒になって炭素数１～６のアルキレンを形成していてもよく、２つあるＲの両方又はいずれか一方がＬ^１に結合していてもよい。

R ¹ represents a hydrogen atom, a linear or branched alkyl group having 1 to 5 carbon atoms, or an aryl group, and two R ^1s on the same maleimide ring may be the same or different; two R ¹ may together form an alkylene having 3 to 6 carbon atoms, W ² represents a divalent organic group, W ¹ represents a single bond or carbonyl, and L ¹ has 1 carbon a divalent group selected from a linear alkylene group of up to 20, a branched alkylene group of 3 to 20 carbon atoms, a cyclic alkylene group of 3 to 20 carbon atoms, a phenylene group and a heterocyclic group, or the divalent group represents a group formed by multiple bonds, and the phenylene group and the heterocyclic group are each independently selected from alkyl groups, alkoxy groups, haloalkyl groups, haloalkoxy groups, halogen groups and cyano groups. may be substituted with a group, and the bond between the divalent groups is at least one selected from a single bond, an ester bond, an amide bond, a urea bond, an ether bond, a thioether bond, an amino bond and a carbonyl, When there are multiple divalent groups, the divalent groups may be the same or different, and when there are multiple bonds, the bonds may be the same or different, and R is a hydrogen atom or represents a monovalent organic group, the two R may be different from each other, the two R may together form an alkylene having 1 to 6 carbon atoms, and both of the two R Alternatively, either one may be bound to ^L1 .

2. 1. said W ¹ represents a single bond; The diamine described in .

3. 1. Said W ² is selected from W ² -7, W ² -20 to W ² -26, W ² -39 to W ² -43, W ² -51 to W ² -71; or 2. The diamine described in .

4. 1. ~3. A polymer using any one of the diamines.

5. 4. At least one selected from polyimide precursors containing structural units represented by the following formula (3), and polyimides which are imidized products thereof; The polymer described in .

Ｘ^１はテトラカルボン酸誘導体に由来する４価の有機基を表し、Ｙ^１は式（１）の構造を含むジアミンに由来する２価の有機基を表し、Ｒ^４は水素原子又は炭素数１～５のアルキル基を表す。

X ¹ represents a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ¹ represents a divalent organic group derived from a diamine containing the structure of formula (1), and R ⁴ represents a hydrogen atom or 1 carbon atom. represents an alkyl group of ∼5.

6. 5. In the formula (3), the structure of ^X1 represents at least one selected from the following structures; The polymer described in .

7. 5. At least one selected from polyimide precursors further containing a structural unit represented by the following formula (4), and polyimides which are imidized products thereof; The polymer described in .

式（４）において、Ｘ^２はテトラカルボン酸誘導体に由来する４価の有機基を表し、Ｙ^２は式（１）の構造を主鎖方向に含まないジアミンに由来する２価の有機基を表し、Ｒ^１４は、それぞれ独立に水素原子又は炭素数１～５のアルキル基を表し、Ｒ^１５はそれぞれ独立に水素原子又は炭素数１～４のアルキル基を表す。

In formula (4), ^X2 represents a tetravalent organic group derived from a tetracarboxylic acid derivative, and ^Y2 represents a divalent organic group derived from a diamine that does not contain the structure of formula (1) in the main chain direction. Each R ¹⁴ independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and each R ¹⁵ independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

8. 6. ^Y2 is represented by the following formula (11); The polymer described in .

式（１１）中、Ｒ^３２は単結合又は２価の有機基を表し、Ｒ^３３は－（ＣＨ_２）_ｒ－で表される構造を表し、ｒは２～１０の整数を表し、また、任意の－ＣＨ_２－はそれぞれ隣り合わない条件でエーテル、エステル、アミド、ウレア、カルバメート結合に置き換えられてもよい。Ｒ^３４は単結合又は２価の有機基を表す。ベンゼン環上の任意の水素原子は１価の有機基で置き換えられてもよい。

In formula (11), R ³² represents a single bond or a divalent organic group, R ³³ represents a structure represented by —(CH ₂ ) _r —, r represents an integer of 2 to 10, and Any —CH ₂ — may be replaced with an ether, ester, amide, urea, or carbamate bond under the condition that they are not adjacent to each other. ^R34 represents a single bond or a divalent organic group. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group.

9. 5. The structural unit represented by the formula (3) is 10 mol % or more of all structural units; or 6. The polymer described in .

By using a liquid crystal aligning agent containing the polymer using the diamine of the present invention, it is possible to suppress the ion density in the liquid crystal display element to a low level and to quickly relax the accumulated electric charge, especially in the horizontal electric field driving method. It is possible to obtain a liquid crystal alignment film that can suppress the deviation between the rubbing direction and the liquid crystal alignment direction, which is a problem in the above. Although it is not clear why the present invention can solve the above problems, it is generally considered as follows. The structure of the above formula (1) contained in the polymer using the diamine of the present invention has a nitrogen atom. As a result, for example, in the liquid crystal alignment film, it has the ability to capture ionic impurities, promote the transfer of charges, and facilitate the relaxation of accumulated charges.

The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent containing a polymer (hereinafter also referred to as a specific polymer) obtained from a diamine having a structure represented by the above formula (1) (hereinafter also referred to as a specific structure). be. Each condition will be described in detail below.

<Diamine having a specific structure>
In the above formula (1), R ¹ represents a ^hydrogen atom, an optionally linear or branched alkyl group having 1 to 5 carbon atoms, or an aryl group; may be different, two R ¹ may together form an alkylene having 3 to 6 carbon atoms, W ² represents a divalent organic group, L ¹ is a single bond or has 1 carbon ~20 alkylene, R represents a hydrogen atom or a monovalent organic group, the two R may be different from each other, and the two R together form an alkylene having 1 to 6 carbon atoms and both or either one of the two Rs may be bonded to ^L1 .

R ¹ is preferably a hydrogen atom, a methyl group, an ethyl group, an iso-propyl group or a phenyl group, more preferably a hydrogen atom, a methyl group or a phenyl group. The alkylene having 3 to 6 carbon atoms formed by two R ¹ together is preferably -(CH ₂ ) ₃ -, -(CH ₂ ) ₄ -, or -(CH ₂ ) ₅ -. and more preferably -(CH ₂ ) ₄ -.

The alkylene having 1 to 20 carbon atoms in the definition of L ¹ may be linear or branched, and is a linear chain represented by —(CH ₂ ) _n — (where n is 1 to 20). alkylene, 1-methylmethane-1,1-diyl, 1-ethylmethane-1,1-diyl, 1-propylmethane-1,1-diyl, 1-methylethane-1,2-diyl, 1-ethylethane- 1,2-diyl, 1-propylethane-1,2-diyl, 1-methylpropane-1,3-diyl, 1-ethylpropane-1,3-diyl, 1-propylpropane-1,3-diyl, 2-methylpropane-1,3-diyl, 2-ethylpropane-1,3-diyl, 2-propylpropane-1,3-diyl, 1-methylbutane-1,4-diyl, 1-ethylbutane-1,4 -diyl, 1-propylbutane-1,4-diyl, 2-methylbutane-1,4-diyl, 2-ethylbutane-1,4-diyl, 2-propylbutane-1,4-diyl, 1-methylpentane- 1,5-diyl, 1-ethylpentane-1,5-diyl, 1-propylpentane-1,5-diyl, 2-methylpentane-1,5-diyl, 2-ethylpentane-1,5-diyl, 2-propylpentane-1,5-diyl, 3-methylpentane-1,5-diyl, 3-ethylpentane-1,5-diyl, 3-propylpentane-1,5-diyl, 1-methylhexane- 1,6-diyl, 1-ethylhexane-1,6-diyl, 2-methylhexane-1,6-diyl, 2-ethylhexane-1,6-diyl, 3-methylhexane-1, 6-diyl, 3-ethylhexane-1,6-diyl, 1-methylheptane-1,7-diyl, 2-methylheptane-1,7-diyl, 3-methylheptane-1,7-diyl, 4 -methylheptane-1,7-diyl, 1-phenylmethane-1,1-diyl, 1-phenylethane-1,2-diyl, 1-phenylpropane-1,3-diyl and other branched alkylenes. These linear or branched alkylenes may be interrupted 1 to 5 times by oxygen atoms or sulfur atoms provided that the oxygen atoms or sulfur atoms are not adjacent to each other.

Branched alkylene groups having 3 to 20 carbon atoms in the definition of L ¹ include, for example, i-propylene group, i-butylene group, s-butylene group, t-butylene group, 1-methyl-n-butylene group, 2 -methyl-n-butylene group, 3-methyl-n-butylene group, 1,1-dimethyl-n-propylene group, 1,2-dimethyl-n-propylene group, 2,2-dimethyl-n-propylene group, 1-ethyl-n-propylene group, 1-methyl-n-pentylene group, 2-methyl-n-pentylene group, 3-methyl-n-pentylene group, 4-methyl-n-pentylene group, 1,1-dimethyl -n-butylene group, 1,2-dimethyl-n-butylene group, 1,3-dimethyl-n-butylene group, 2,2-dimethyl-n-butylene group, 2,3-dimethyl-n-butylene group, 3,3-dimethyl-n-butylene group, 1-ethyl-n-butylene group, 2-ethyl-n-butylene group, 1,1,2-trimethyl-n-propylene group, 1,2,2-trimethyl- In addition to the n-propylene group, 1-ethyl-1-methyl-n-propylene group and 1-ethyl-2-methyl-n-propylene group, etc., having up to 20 carbon atoms and branching at any point alkylene group, and the like.

The cyclic alkylene group having 3 to 20 carbon atoms in the definition of L ¹ includes, for example, monocyclic alkylene groups such as cyclopropylene group, cyclobutylene group, cyclopentylene group, cyclohexylene group, cycloheptylene group and cyclooctylene group. , and polycyclic alkylene groups such as norbornylene, tricyclodecylene, tetracyclododecylene and adamantylene groups.

Examples of substituents when the benzene ring in the definition of L ¹ may be substituted with a substituent include alkyl groups such as methyl group, ethyl group, propyl group, butyl group and isobutyl group; haloalkyl groups such as trifluoromethyl group group; alkoxy group such as methoxy group and ethoxy group; halogen atom such as iodine, bromine, chlorine and fluorine; cyano group and the like.

R is preferably a hydrogen atom or a linear alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group. Further, R may be a protective group that undergoes a desorption reaction by heat and is substituted with a hydrogen atom. It is a protective group that is released, more preferably a protective group that is released by heat at 100° C. or higher. Examples thereof include 1,1-dimethyl-2-chloroethoxycarbonyl group, 1,1-dimethyl-2-cyanoethoxycarbonyl group and tert-butoxycarbonyl group, preferably tert-butoxycarbonyl group.

The alkylene having 3 to 6 carbon atoms formed by two R together is preferably -CH ₂ -, -(CH ₂ ) ₂ -, -(CH ₂ ) ₃ -, -(CH ₂ ) ₄ -, -(CH ₂ ) ₅ -, more preferably -(CH ₂ ) ₂ - or -(CH ₂ ) ₃ -. The divalent organic group W ² is represented by the following formulas [W ² -1] to [W ² -152].

Among them, W ² -7, W ² -20, W ² -21, W ² -23, W ² -26, W ² -39, W ² -51 from the viewpoint of compatibility between ion density suppression and liquid crystal orientation stability , ^W2-52 , ^W2-53 , ^W2-54 , ^W2-55 , ^W2-59 , ^W2-60 , ^W2-61 , ^W2-64 , ^W2-65 , ^W2-67 , W ² -68, W ² -69, W ² -70, W ² -71 are preferred.

<Method for producing specific diamine>
A method for obtaining the diamine described above will be described below. Among the specific diamines represented by formula (1) of the present invention, the method for synthesizing the diamine in which ^W1 is a single bond is not particularly limited. For example, a nitromaleimide compound represented by the following formula (A), A method of reacting with a diamino compound represented by the following formula (B1) to obtain an aminonitro compound represented by the following formula (C1) and reducing it can be mentioned.

Ｒ、Ｒ^１、Ｌ^１、Ｗ¹及びＷ^２の定義は、上記式（１）と同様である。

The definitions of R, R ¹ , L ¹ , W ¹ and W ² are the same as in formula (1) above.

The amount of the compound represented by formula (B1) to be used is preferably 0.1 mol to 1 mol, more preferably 0.4 mol to 0.4 mol, per 1 mol of the compound represented by formula (A). More preferably 5 mol. By using an excessive amount of the compound represented by the formula (A), the reaction can proceed smoothly and the production of by-products can be suppressed.

This reaction is preferably carried out in a solvent. Any solvent can be used without limitation as long as it does not react with each raw material. For example, aprotic polar organic solvents (DMF, DMSO, DMAc, NMP, etc.); ethers (Et ₂ O, i-Pr ₂ O, TBME, CPME, THF, dioxane, etc.); aliphatic hydrocarbons (pentane, hexane, heptane, petroleum ether, etc.); aromatic hydrocarbons (benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, nitrobenzene, tetralin, 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.); These solvents can be appropriately selected in consideration of the easiness of reaction and the like, and can be used singly or in combination of two or more. If necessary, the solvent can be dried using a suitable dehydrating agent or drying agent and used as a non-aqueous solvent.

The amount (reaction concentration) of the solvent used is not particularly limited, but it is 0.1 to 100 times the weight of the bismaleimide compound. It is preferably 0.5 to 30 times by mass, more preferably 1 to 10 times by mass. The reaction temperature is not particularly limited, but is in the range from -100°C to the boiling point of the solvent used, preferably -50 to 150°C. The reaction time is usually 0.05 hours to 350 hours, preferably 0.5 hours to 100 hours.

This reaction can be carried out in the presence of an inorganic base or an organic base, if necessary. The base used in the reaction includes inorganic bases such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, potassium phosphate, sodium carbonate, potassium carbonate, lithium carbonate, and cesium carbonate; Bases such as sodium, tert-butoxypotassium, sodium hydride, potassium hydride; and amines such as trimethylamine, triethylamine, tripropylamine, triisopropylamine, tributylamine, diisopropylethylamine, pyridine, quinoline, collidine and the like can be used. Among them, triethylamine, pyridine, tert-butoxysodium, tert-butoxypotassium, sodium hydride, potassium hydride and the like are preferable. The amount of the base to be used is not particularly limited, but it is 0.1 to 100 parts by mass relative to the bismaleimide compound. It is preferably 0 to 30 times by mass, more preferably 0 to 10 times by mass.

One embodiment of compound (B1) is a compound represented by the following formula (B1-1), wherein L ¹ is a divalent organic group, R is a hydrogen atom, and W ¹ is a single bond. .

Each R in formula (B1-1) is independently a hydrogen atom or a monovalent organic group, preferably a hydrogen atom or a linear alkyl group having 1 to 3 carbon atoms. L ¹ of the compound of formula (B1-1) includes structures selected from the above W ² -1 to W ² -152. Preferably, it is selected from the following structures, but is not limited thereto.

One embodiment of compound (B1) is that L ¹ is a divalent organic group, W ¹ is a single bond, and R together form an alkylene group, or two R ¹ is a compound represented by the following formula (B1-2).

The compound of formula (B1-2) is preferably selected from the following structural formulas.

One embodiment of the compound (B1 ^{) is} represented by the ^following formula (B1 -3) is a compound represented by

Each R in formula (B1-3) is independently a hydrogen atom or a monovalent organic group, preferably a hydrogen atom or a linear alkyl group having 1 to 3 carbon atoms. Preferred examples of the compound of formula (B1-3) include the following compounds.

Next, the conditions for producing the specific diamine represented by formula (1) by reducing the compound represented by formula (C1) are described below. As a method for reducing the compound represented by the above formula (C1), there is a reduction reaction performed in the coexistence of Fe, Sn, Zn or salts thereof and protons. The amount of Fe, Sn, Zn and salts thereof to be used is preferably 1 equivalent to 100 equivalents, particularly preferably 3 equivalents to 50 equivalents, relative to the compound represented by formula (1).

As the reaction solvent, any solvent can be used as long as it does not interfere with the intended reaction under the reaction conditions. For example, water; alcohol solvents such as methyl alcohol, ethyl alcohol, tert-butyl alcohol; aprotic polar organic solvents such as dimethylformamide, dimethylsulfoxide, dimethylacetamide, N-methylpyrrolidone; diethyl ether, diisopropyl ether, tert-butyl ethers such as methyl ether, cyclopentyl methyl ether, tetrahydrofuran and dioxane; aliphatic hydrocarbons such as pentane, hexane, heptane and petroleum ether; aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene and tetralin, chloroform, dichloromethane, Halogen hydrocarbons such as carbon tetrachloride and dichloroethane; lower fatty acid esters such as methyl acetate, ethyl acetate, butyl acetate and methyl propionate; and nitriles such as acetonitrile, propionitrile and butyronitrile. These solvents can be appropriately selected in consideration of the easiness of reaction and the like, and can be used singly or in combination of two or more. In some cases, the above solvent can also be used as a solvent that does not contain water by using a suitable dehydrating agent or drying agent. The amount (reaction concentration) of the solvent used is not particularly limited, but is 0.1 to 100 times the mass of the compound represented by the above formula (C1). It is preferably 0.5 to 50 times by mass, more preferably 3 to 30 times by mass.

Furthermore, the reaction can be carried out under pressure in order to proceed the reaction more effectively. In this case, in order to avoid reduction of the benzene nucleus, the reaction is preferably carried out in a pressure range of about 20 atmospheres (kgf), more preferably up to 10 atmospheres. Furthermore, acids such as hydrochloric acid, sulfuric acid, formic acid, and acetic acid, and their salts may coexist. The amount of these to be used is not particularly limited, but is 0 to 10 times the mass of the compound represented by the above formula (C1). It is preferably 0-fold to 5-fold by mass, more preferably 0-fold to 3-fold by mass. The reaction temperature is preferably selected from a temperature range of -100°C or higher to the boiling point of the reaction solvent used, more preferably -50°C to 150°C, particularly preferably 0°C to 100°C. is. The reaction time is 0.1 hour to 1000 hours, more preferably 1 hour to 200 hours. Methods for reducing the compound represented by the above formula (C1) include a hydrogenation reaction using palladium-activated carbon or platinum-activated carbon as a catalyst, a reduction reaction using formic acid as a hydrogen source, and a hydrogenation reaction using hydrazine as a hydrogen source. There are reactions to Moreover, these reactions can also be implemented in combination.

The catalyst used for the reduction reaction is preferably a commercially available metal supported on activated carbon, such as palladium-activated carbon, platinum-activated carbon, and rhodium-activated carbon. In addition, palladium hydroxide, platinum oxide, Raney nickel, and the like may not necessarily be metal catalysts supported on activated carbon. Palladium-activated charcoal and platinum-activated charcoal, which are generally widely used, are preferable because good results can be obtained.

The amount of these catalysts to be used may be a so-called catalytic amount, preferably 20 mol % or less, particularly preferably 10 mol % or less, relative to the compound represented by the above formula (C1).

As the reaction solvent, any solvent can be used as long as it does not interfere with the intended reaction under the reaction conditions. For example, alcohol solvents such as methyl alcohol, ethyl alcohol, tert-butyl alcohol; aprotic polar organic solvents such as dimethylformamide, dimethylsulfoxide, dimethylacetamide, N-methylpyrrolidone; diethyl ether, isopropyl ether, tert-butyl methyl ether. Ethers such as , cyclopentyl methyl ether, tetrahydrofuran, dioxane; Aliphatic hydrocarbons such as pentane, hexane, heptane, petroleum ether; Aromatic hydrocarbons such as benzene, toluene, xylene, mesitylene, tetralin, chloroform, dichloromethane, tetrachloride Halogen hydrocarbons such as carbon and dichloroethane; lower fatty acid esters such as methyl acetate, ethyl acetate, butyl acetate and methyl propionate; and nitriles such as acetonitrile, propionitrile and butyronitrile. These solvents can be appropriately selected in consideration of the easiness of reaction and the like, and can be used singly or in combination of two or more. In some cases, the above solvent can also be used as a solvent that does not contain water by using a suitable dehydrating agent or drying agent. The amount (reaction concentration) of the solvent used is not particularly limited, but is 0.1 to 100 times the mass of the compound represented by the above formula (C1). It is preferably 0.5 to 50 times by mass, more preferably 3 to 30 times by mass. The reaction temperature is not particularly limited, but is in the range from -100°C to the boiling point of the solvent used, preferably -50°C to 150°C. The reaction time is usually 0.05 hours to 350 hours, preferably 0.5 hours to 100 hours.

In order to promote the reduction reaction more effectively, the reaction may be carried out in the presence of activated carbon. At this time, the amount of activated carbon used is not particularly limited, but it is preferably in the range of 1% to 30% by mass, more preferably 10% to 20% by mass, based on the dinitro compound C1. For similar reasons, the reaction may also be carried out under pressure. In this case, in order to avoid reduction of the benzene nucleus, the pressure range is up to 20 atmospheres. The reaction is preferably carried out in a range of up to 10 atmospheres. Among the reduction reactions exemplified above, the hydrogenation reaction is preferably used in consideration of the structure of the compound represented by the formula (C1) and the reactivity of the reduction reaction.

When it is desired to introduce a monovalent organic group as R, a compound in which R is a hydrogen atom in the dinitro compound represented by the above formula (C1) may be reacted with a compound capable of reacting with amines. Examples of such compounds include acid halides, acid anhydrides, isocyanates, epoxies, oxetanes, aryl halides, and alkyl halides. can be used.

The method of introducing a monovalent organic group into the NH group is not particularly limited, but examples include a method of reacting an acid halide in the presence of a suitable base. Examples of acid halides include acetyl chloride, propionyl chloride, methyl chloroformate, ethyl chloroformate, n-propyl chloroformate, i-propyl chloroformate, n-butyl chloroformate, i-butyl chloroformate, t-chloroformate Butyl, benzyl chloroformate, and 9-fluorenyl chloroformate. Examples of bases that can be used include those described above. The reaction solvent and reaction temperature conform to those described above.

A monovalent organic group may be introduced by reacting the NH group with an acid anhydride, and examples of the acid anhydride include acetic anhydride, propionic anhydride, dimethyl dicarbonate, diethyl dicarbonate, and ditertiary butyl dicarbonate. , and dibenzyl dicarbonate. A catalyst may be added to promote the reaction, and pyridine, collidine, N,N-dimethyl-4-aminopyridine and the like may be used. The catalyst amount is 0.0001 mol to 1 mol per 1 mol of the dinitro compound represented by the above formula (C1) in which R is a hydrogen atom. The reaction solvent and reaction temperature conform to those described above.

Monovalent organic groups may be introduced by reacting NH groups with isocyanates, and examples of isocyanates include methyl isocyanate, ethyl isocyanate, n-propyl isocyanate, and phenyl isocyanate. The reaction solvent and reaction temperature conform to those described above.

Epoxy compounds and oxetane compounds may be reacted with NH groups to introduce monovalent organic groups. Examples of epoxies and oxetanes include ethylene oxide, propylene oxide, 1,2-butylene oxide and trimethylene. oxide and the like. The reaction solvent and reaction temperature conform to those described above.

A monovalent organic group may be introduced by reacting an aryl halide to the NH group in the presence of a metal catalyst, a ligand and a base, and examples of the aryl halide include iodobenzene, bromobenzene, chlorobenzene, and the like. is mentioned. Examples of metal catalysts include palladium acetate, palladium chloride, palladium chloride-acetonitrile complex, palladium-activated carbon, bis(dibenzylideneacetone)palladium, tris(dibenzylideneacetone)dipalladium, bis(acetonitrile)dichloropalladium, bis(benzo nitrile)dichloropalladium, CuCl, CuBr, CuI, CuCN, and the like, but are not limited to these. Examples of ligands include triphenylphosphine, tri-o-tolylphosphine, diphenylmethylphosphine, phenyldimethylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane. , 1,4-bis(diphenylphosphino)butane, 1,1′-bis(diphenylphosphino)ferrocene, trimethylphosphite, triethylphosphite, triphenylphosphite, tri-tert-butylphosphine and the like. , but not limited to these. Examples of bases that can be used include those described above. The reaction solvent and reaction temperature conform to those described above.

A monovalent organic group may be introduced by reacting the NH group with an alcohol in which the hydroxyl group of the alcohol is substituted with a leaving group such as OMs, OTf, or OTs in the presence of an appropriate base. , methanol, ethanol, 1-propanol, etc., and by reacting these alcohols with methanesulfonyl chloride, trifluoromethanesulfonyl chloride, p-toluenesulfonyl chloride, etc., elimination of OMs, OTf, OTs, etc. Group-substituted alcohols can be obtained. Examples of bases that can be used include those described above. The reaction solvent and reaction temperature conform to those described above.

An alkyl halide may be reacted with an NH group in the presence of an appropriate base to introduce a monovalent organic group. Examples of alkyl halides include methyl iodide, ethyl iodide, and n-propyl iodide. , methyl bromide, ethyl bromide, n-propyl bromide, and the like. Examples of bases that can be used include metal alkoxides such as potassium-tert-butoxide and sodium-tert-butoxide in addition to the aforementioned bases. The reaction conditions such as the reaction solvent, reaction temperature and reaction time conform to those described above.

The amount of the compound capable of reacting with the above amines is 1.0 molar equivalent to 1.0 molar equivalent to 1.0 molar equivalent of the dinitro compound represented by the above formula (C) in which R is a hydrogen atom. It can be about 0.0 molar equivalent. It is preferably in the range of 2.0 molar equivalents to 2.5 molar equivalents. In addition, the compounds capable of reacting with the above amines can be used alone or in combination. When the diamine compound represented by the formula (1) has isomers derived from an asymmetric point, in the present application, each isomer and a mixture thereof are both the diamine represented by the formula (1). shall be included. Further, when two R ¹ in the same maleimide ring of formula (1) are different from each other, the diamine compound represented by formula (1) differs in the substitution position of R ¹ . All mixtures thereof are also included in the diamine represented by formula (1).

[Manufacturing method of formula (A)]
The method for synthesizing the compound of formula (A) is not particularly limited, but examples include a method of reacting a commercially available nitroamine represented by the following formula (D) with a maleic anhydride derivative.

The amount of the maleic anhydride derivative used is preferably 1 mol to 1.5 mol, more preferably 1 mol to 1.2 mol, per 1 mol of the nitroamine compound represented by the formula (D). More preferred. By using an excessive amount of maleic anhydride, the reaction can proceed smoothly and by-products can be suppressed. This reaction is preferably carried out in a solvent. Preferred solvents and reaction conditions are the same as those for the production of compound (1) above. Further, among the specific diamines represented by the formula (1) of the present invention, as a method for synthesizing a diamine in which ^W1 is a single bond, an aminomaleimide compound represented by the following formula (E) and the above formula ( A method of reacting with a diamino compound represented by B1-1) can also be mentioned.

The definitions of R, R ¹ , L ¹ and W ² are the same as in formula (1) above. The amount of the compound represented by formula (B1-1) to be used is preferably 0.1 mol to 1 mol, and 0.4 mol to 1 mol, per 1 mol of the compound represented by formula (E). More preferably 0.5 mol. By using an excessive amount of the compound represented by formula (E), the reaction can proceed smoothly and the production of by-products can be suppressed.

This reaction is preferably carried out in a solvent. Any solvent can be used without limitation as long as it does not react with each raw material. For example, aprotic polar organic solvents (DMF, DMSO, DMAc, NMP, etc.); ethers (Et ₂ O, i-Pr ₂ O, TBME, CPME, THF, dioxane, etc.); aliphatic hydrocarbons (pentane, hexane, heptane, petroleum ether, etc.); aromatic hydrocarbons (benzene, toluene, xylene, mesitylene, chlorobenzene, dichlorobenzene, nitrobenzene, tetralin, 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.); These solvents can be appropriately selected in consideration of the easiness of reaction and the like, and can be used singly or in combination of two or more. If necessary, the solvent can be dried using a suitable dehydrating agent or drying agent and used as a non-aqueous solvent. The amount (reaction concentration) of the solvent used is not particularly limited, but is 0.1 to 100 times the weight of the bismaleimide compound. It is preferably 0.5 to 30 times by mass, more preferably 1 to 10 times by mass. The reaction temperature is not particularly limited, but is in the range from -100°C to the boiling point of the solvent used, preferably -50°C to 150°C. The reaction time is usually 0.05 hours to 350 hours, preferably 0.5 hours to 100 hours.

This reaction can be carried out in the presence of an inorganic base or an organic base, if necessary.
The base used in the reaction includes inorganic bases such as sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium hydrogen carbonate, potassium hydrogen carbonate, potassium phosphate, sodium carbonate, potassium carbonate, lithium carbonate, and cesium carbonate; Bases such as sodium, tert-butoxypotassium, sodium hydride, potassium hydride; and amines such as trimethylamine, triethylamine, tripropylamine, triisopropylamine, tributylamine, diisopropylethylamine, pyridine, quinoline, collidine and the like can be used. Among them, triethylamine, pyridine, tert-butoxysodium, tert-butoxypotassium, sodium hydride, potassium hydride and the like are preferable. The amount of the base used is not particularly limited, but it is 0.1 to 100 times the weight of the bismaleimide compound. It is preferably 0 to 30 times by mass, more preferably 0 to 10 times by mass.

[Manufacturing method of formula (E)]
Although the method for synthesizing the compound of formula (E) is not particularly limited, for example, a diamine represented by the following formula (F) is subjected to maleic anhydride A method of reacting an acid derivative can be mentioned.

The amount of the maleic anhydride derivative to be used is preferably 0.01 mol to 1 mol, more preferably 0.1 mol to 1.0 mol, per 1 mol of the diamine compound represented by formula (F). is more preferred. By using an excessive amount of the diamine (F), the reaction can proceed smoothly and the production of by-products can be suppressed. This reaction is preferably carried out in a solvent. Preferred solvents and reaction conditions are the same as those for the production of compound (1) above. Moreover, the method of carrying out metal catalytic reduction of the diamine represented by the following formula (A) is also mentioned.

This reaction conforms to the method for producing the specific diamine represented by the formula (1) by reducing the compound (C1). Considering the structure of the compound represented by formula (A) and the reactivity of the reductive reaction, the reductive reaction is preferably carried out in the presence of Fe, Sn, Zn or salts thereof and protons.

Among the specific diamines represented by the formula (1) of the present invention, the method for synthesizing the diamine in which ^W1 is carbonyl is not particularly limited. After reacting an amine represented by the formula (B2) to obtain a compound represented by the following formula (G), this is reacted with a dicarboxylic acid represented by the following formula (H) to obtain a compound represented by the following formula (C2) A method of obtaining a dinitro compound represented by and reducing it can be exemplified.

Ｒ、Ｒ^１、Ｌ^１及びＷ^２の定義は、上記式（１）と同様である。

The definitions of R, R ¹ , L ¹ and W ² are the same as in formula (1) above.

Preferred L ¹ in formulas (H) and (C2) is the same as preferred L ¹ in formula (B1-1) above. The reaction conditions for the compound represented by formula (B2) and the compound represented by formula (A) are the same as the reaction conditions for the compound represented by formula (B1) above and the compound represented by formula (A). comply.

The compound represented by the above formula (G) and the compound represented by the above formula (H) in which Z is OH are subjected to condensation using a solvent inert to the reaction, if necessary, in the presence of a base, if necessary. A compound represented by the general formula (C2) can be obtained by reacting with an agent.
The amount of the reaction substrate is 0.4 to 0.8 equivalents per equivalent of the compound represented by formula (G), in which Z is OH in general formula (H).

The condensing agent is not particularly limited as long as it is commonly used in amide synthesis, and examples include Mukaiyama reagent (2-chloro-N-methylpyridinium iodide), DCC (1,3-dicyclohexylcarbodiimide), WSC (1 -ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride), CDI (carbonyldiimidazole), dimethylpropynylsulfonium bromide, propargyltriphenylphosphonium bromide, DEPC (diethyl cyanophosphate), etc. can be used in an amount of 1 to 4 equivalents relative to the compound in which Z is OH.

When a solvent is used, the solvent to be used is not particularly limited as long as it does not hinder the progress of the reaction. Examples include aromatic hydrocarbons such as benzene, toluene and xylene, and aliphatic hydrocarbons such as hexane and heptane. , cyclohexane and other alicyclic hydrocarbons, chlorobenzene, dichlorobenzene and other aromatic halogenated hydrocarbons, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1,1-trichloroethane, trichlorethylene, tetrachlorethylene aliphatic halogenated hydrocarbons such as diethyl ether, 1,2-dimethoxyethane, tetrahydrofuran, 1,4-dioxane and other ethers, ethyl acetate, ethyl propionate and other esters, N,N-dimethylformamide, amides such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone; amines such as triethylamine, tributylamine and N,N-dimethylaniline; pyridines such as pyridine and picoline; be done. These solvents may be used alone, or two or more of them may be mixed and used.

Addition of a base is not always necessary, but when a base is used, examples include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, sodium hydrogen carbonate and potassium hydrogen carbonate. alkali metal bicarbonate such as triethylamine, tributylamine, N,N-dimethylaniline, pyridine, 4-(dimethylamino)pyridine, imidazole, 1,8-diazabicyclo[5,4,0]-7-undecene, etc. An organic base or the like can be used in an amount of 1 to 4 equivalents relative to the compound in which Z is OH in the above formula (H).

The reaction temperature can be set at any temperature from -60°C to the reflux temperature of the reaction mixture, and the reaction time varies depending on the concentration of the reaction substrate and the reaction temperature, but is usually arbitrarily in the range of 5 minutes to 100 hours. Can be set.

In general, for example, 0.4 equivalent to 0.8 equivalent of the compound represented by the above formula (G), in which Z is OH, and 1 equivalent to 4 equivalents of Using a condensing agent such as WSC (1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride) or CDI (carbonyldiimidazole), if necessary 1 to 4 equivalents of potassium carbonate, triethylamine, pyridine, 4 -In the presence of a base such as (dimethylamino)pyridine, using no solvent or a solvent such as dichloromethane, chloroform, diethyl ether, tetrahydrofuran, 1,4-dioxane, etc., at a temperature range from 0°C to the reflux temperature of these solvents. , preferably from 10 minutes to 24 hours.

In addition, a compound of the above formula (H) in which Z is OH is reacted with a chlorinating agent such as thionyl chloride, phosphorus pentachloride or oxalyl chloride, a method described in literature, pivaloyl chloride or isobutyl chloroformate. and an organic acid halide such as Z is Cl and the compound represented by the above formula (G), if necessary using a solvent inert to the reaction, if necessary in the presence of a base, to give the general formula ( Compounds represented by C2) can also be synthesized. The amount of the reaction substrate is 0.4 to 0.8 equivalents of the compound represented by the general formula (H) wherein Z is Cl with respect to 1 equivalent of the compound represented by the formula (G).

When a solvent is used, the solvent to be used is not particularly limited as long as it does not hinder the progress of the reaction. Examples include aromatic hydrocarbons such as benzene, toluene and xylene, and aliphatic hydrocarbons such as hexane and heptane. , cyclohexane and other alicyclic hydrocarbons, chlorobenzene, dichlorobenzene and other aromatic halogenated hydrocarbons, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1,1-trichloroethane, trichlorethylene, tetrachlorethylene aliphatic halogenated hydrocarbons such as diethyl ether, 1,2-dimethoxyethane, tetrahydrofuran, 1,4-dioxane and other ethers, ethyl acetate, ethyl propionate and other esters, N,N-dimethylformamide, amides such as N,N-dimethylacetamide and N-methyl-2-pyrrolidone; amines such as triethylamine, tributylamine and N,N-dimethylaniline; pyridines such as pyridine and picoline; . These solvents may be used alone, or two or more of them may be mixed and used.

Addition of a base is not always necessary, but when a base is used, examples include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, sodium hydrogen carbonate and potassium hydrogen carbonate. alkali metal bicarbonates such as triethylamine, tributylamine, N,N-dimethylaniline, pyridine, 4-(dimethylamino)pyridine, imidazole, 1,8-diazabicyclo[5,4,0]-7-undecene, etc. An organic base or the like can be used in an amount of 1 to 4 equivalents relative to the compound in which Z is Cl in the above formula (H). The reaction temperature can be set at any temperature from -60°C to the reflux temperature of the reaction mixture, and the reaction time varies depending on the concentration of the reaction substrate and the reaction temperature, but is usually arbitrarily in the range of 5 minutes to 100 hours. Can be set.

In general, for example, 0.4 to 0.8 equivalents of the compound represented by the general formula (H) in which Z is Cl with respect to 1 equivalent of the compound represented by the formula (G), if necessary, 1 equivalent to In the presence of a base such as 2 equivalents of potassium carbonate, triethylamine, pyridine, 4-(dimethylamino)pyridine, no solvent or a solvent such as dichloromethane, chloroform, diethyl ether, tetrahydrofuran, 1,4-dioxane, ethyl acetate, acetonitrile and the reaction is preferably carried out at a temperature in the range of 0° C. to the reflux temperature of these solvents for 10 minutes to 48 hours. The reaction conditions for reducing the dinitro compound represented by formula (C2) to obtain the diamine represented by formula (1) are the same as those described above.

The target product obtained in each step obtained by each of the above reactions may be purified by distillation, recrystallization, or column chromatography using silica gel or the like, or the reaction solution may be directly subjected to the next step without purification. can also

<Polymer>
The polymer of the present invention is a polymer obtained using the above diamine. Specific examples include polyamic acid, polyamic acid ester, polyimide, polyurea, and polyamide. and polyimide which is an imidized product thereof.

In the above formula (3), X ¹ is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ¹ is a divalent organic group derived from a diamine containing the structure of formula (1), and R ⁴ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. R ⁴ is preferably a hydrogen atom, a methyl group, or an ethyl group from the viewpoint of ease of imidization by heating.

<Tetracarboxylic dianhydride>
^X1 is a tetravalent organic group derived from a tetracarboxylic acid derivative, and its structure is not particularly limited. In addition, X ¹ in the polyimide precursor is required for the solubility of the polymer in a solvent, the applicability of the liquid crystal alignment agent, the alignment of the liquid crystal when used as a liquid crystal alignment film, the voltage holding ratio, the accumulated charge, etc. It may be selected appropriately according to the degree of the properties to be obtained, and one type may be used in the same polymer, or two or more types may be mixed.
Specific examples of X ¹ include structures of formulas (X-1) to (X-46) described on pages 13 to 14 of International Publication 2015/119168. Preferred structures of ^X1 are shown below, but the present invention is not limited thereto.

Among the above structures, (A-1) and (A-2) are particularly preferable from the viewpoint of further improving rubbing resistance, and (A-4) is particularly preferable from the viewpoint of further improving the relaxation rate of accumulated charges. , (A-15) to (A-17) are particularly preferred from the viewpoint of further improving the liquid crystal orientation and the relaxation rate of accumulated charges.

<Polymer (other structural unit)>
The polyimide precursor containing the structural unit represented by the formula (3) is selected from the structural units represented by the following formula (4) and polyimides thereof as long as the effects of the present invention are not impaired. 1 type may be included.

In formula (4), ^X2 is a tetravalent organic group derived from a tetracarboxylic acid derivative, and ^Y2 is a divalent organic group derived from a diamine that does not contain the structure of formula (1) in the main chain direction. and R ¹⁴ has the same definition as R ⁴ in formula (3) above, and each R ¹⁵ independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

Specific examples of X ² include the same structures as those exemplified for X ¹ in formula (3), including preferred examples. ^Y2 in the polyimide precursor is a divalent organic group derived from a diamine that does not contain the structure of formula (1) in the main chain direction, and its structure is not particularly limited. In addition, Y ² depends on the degree of required characteristics such as the solubility of the polymer in the solvent, the applicability of the liquid crystal alignment agent, the alignment of the liquid crystal when used as a liquid crystal alignment film, the voltage holding ratio, and the accumulated charge. It may be selected as appropriate in the same polymer, and may be of one type or two or more types may be mixed in the same polymer.

Specific examples of Y ² include groups represented by the above formulas [W ² -1] to [W ² -152]. Further, the structure of formula (2) published on page 4 of International Publication 2015/119168, and the formulas (Y-1) to (Y-97) and (Y- 101) to (Y-118) structure; divalent organic group obtained by removing two amino groups from formula (2) published on page 6 of WO 2013/008906; 8 of WO 2015/122413 Divalent organic group with two amino groups removed from formula (1) published on page; structure of formula (3) published on page 8 of International Publication 2015/060360; Japanese Patent Publication 2012- 173514 page 8 of the formula (1) from which two amino groups are removed from the divalent organic group; and divalent organic groups excluding two.

A preferable structure of Y ² includes the structure of the following formula (11).

In formula (11), R ³² is a single bond or a divalent organic group, preferably a single bond. R ³³ is a structure represented by —(CH ₂ ) _r —. r is an integer of 2-10, preferably 3-7. Any --CH ₂ -- may be replaced with an ether, ester, amide, urea, or carbamate bond under the condition that they are not adjacent to each other. ^R34 is a single bond or a divalent organic group. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group, preferably a fluorine atom or a methyl group. Specific examples of the structure represented by formula (11) include, but are not limited to, the following structures.

When the polyimide precursor containing the structural unit represented by the formula (3) contains the structural unit represented by the formula (4) at the same time, the accumulated charges are quickly relaxed, and the rubbing direction and the alignment direction of the liquid crystal are misaligned. From the viewpoint of controlling, the structural unit represented by formula (3) is preferably 1 mol% to 80 mol% with respect to the total of formula (3) and formula (4), more preferably 5 mol % to 60 mol %, particularly preferably 10 mol % to 40 mol %. A preferred structure of ^Y2 includes a structure having at least one selected from the group consisting of an amino group, an imino group, and a nitrogen-containing heterocyclic ring.

Such a structure of Y ² has at least one structure selected from the group consisting of an amino group, an imino group, and a nitrogen-containing heterocyclic ring, or a thermally eliminable group is substituted on the nitrogen atom. The structure is not particularly limited as long as it has at least one structure selected from an amino group, an imino group and a nitrogen-containing heterocyclic ring. If I dare to give a specific example, at least one selected from the group consisting of an amino group, an imino group, and a nitrogen-containing heterocyclic ring represented by the following formulas (YD-1) to (YD-5) A divalent organic group having a structure can be mentioned.

In formula (YD-1), A ₁ is a nitrogen atom-containing heterocyclic ring having 3 to 15 carbon atoms, and Z ₁ is a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms which may have a substituent. be. In formula (YD-2), V ₁ is a hydrocarbon group having 1 to 10 carbon atoms, A ₂ is a monovalent organic group having 3 to 15 carbon atoms having a nitrogen atom-containing heterocyclic ring, or 1 carbon atom It is a disubstituted amino group substituted with ∼6 aliphatic groups. In formula (YD-3), V ₂ is a divalent organic group having 6 to 15 carbon atoms and 1 to 2 benzene rings, V ₃ is alkylene or biphenylene having 2 to 5 carbon atoms, Z ₂ is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a benzene ring, or a thermally eliminable group; a is an integer of 0 to 1; In formula (YD-4), A ₃ is a nitrogen atom-containing heterocyclic ring having 3 to 15 carbon atoms. In formula (YD-5), A ₄ is a nitrogen atom-containing heterocyclic ring having 3 to 15 carbon atoms, and V ₅ is alkylene having 2 to 5 carbon atoms. )

A 1 , A ₂ , A _{3 , and A 4 of formulas (YD-1), (YD-2 )} , (YD-4), and (YD- ₅ ), nitrogen atom-containing heterocycles having 3 to 15 carbon atoms is not particularly limited as long as it has a known structure. Among them are pyrrolidine, pyrrole, imidazole, pyrazole, oxazole, thiazole, piperidine, piperazine, pyridine, pyrazine, indole, benzimidazole, quinoline, isoquinoline, piperazine, piperidine, indole, benzimidazole, imidazole, carbazole, and pyridine. more preferred. Further, the thermally releasable group may be any substituent group that does not detach at room temperature but is detached and replaced by a hydrogen atom when the alignment film is baked. An olenylmethoxycarbonyl group is mentioned.

Specific examples of such Y ² include divalent organic groups having a nitrogen atom represented by the following formulas (YD-6) to (YD-52), which can suppress charge accumulation due to AC drive. Therefore, formulas (YD-14) to (YD-21) are more preferred, and (YD-14) and (YD-18) are particularly preferred.

式（ＹＤ－１４）及び（ＹＤ－２１）中、ｊは０～３の整数である。

In formulas (YD-14) and (YD-21), j is an integer of 0-3.

式（ＹＤ－２４）、（ＹＤ－２５）、（ＹＤ－２８）及び（ＹＤ－２９）中、ｊは０～３の整数である。

In formulas (YD-24), (YD-25), (YD-28) and (YD-29), j is an integer of 0-3.

（式（ＹＤ－５０）中、ｍ、ｎはそれぞれ１～１１の整数であり、ｍ＋ｎは２～１２の整数である。）

(In formula (YD-50), m and n are each an integer of 1 to 11, and m+n is an integer of 2 to 12.)

<Method for producing polyamic acid>
Polyamic acid, which is a polyimide precursor used in the present invention, can be synthesized by the method shown below. Specifically, a tetracarboxylic dianhydride and a diamine are mixed in the presence of an organic solvent at -20°C to 150°C, preferably 0°C to 70°C, for 30 minutes to 24 hours, preferably 1 hour to 12 hours. It can be synthesized by reacting. The organic solvent used in the above reaction is preferably N,N-dimethylformamide, N-methyl-2-pyrrolidone, γ-butyrolactone, etc., from the viewpoint of the solubility of the monomer and polymer. may be used.

The concentration of the polymer is preferably 1% by mass to 30% by mass, more preferably 5% by mass to 20% by mass, from the viewpoints that precipitation of the polymer hardly occurs and that a high molecular weight product is easily obtained. The polyamic acid obtained as described above can be collected by precipitating a polymer by injecting the reaction solution into a poor solvent while stirring well. Further, a purified polyamic acid powder can be obtained by performing precipitation several times, washing with a poor solvent, and drying at normal temperature or by heating. The poor solvent is not particularly limited, but includes water, methanol, ethanol, 2-propanol, hexane, butyl cellosolve, acetone, toluene and the like, preferably water, methanol, ethanol and 2-propanol.

<Method for producing polyimide>
The polyimide used in the present invention can be produced by imidating the polyamic acid. When producing a polyimide from a polyamic acid, chemical imidization by adding a catalyst to the solution of the polyamic acid obtained by the reaction of the diamine component and the tetracarboxylic dianhydride is convenient. Chemical imidization is preferable because the imidization reaction proceeds at a relatively low temperature and the molecular weight of the polymer is less likely to decrease during the imidization process. Chemical imidization can be carried out by stirring a polymer to be imidized in an organic solvent in the presence of a basic catalyst and an acid anhydride. As the organic solvent, the solvent used in the polymerization reaction described above can be used. Basic catalysts include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine and the like. Among them, pyridine is preferable because it has an appropriate basicity for advancing the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among them, acetic anhydride is preferred because it facilitates purification after the reaction is completed.

The imidization reaction temperature is -20°C to 140°C, preferably 0°C to 100°C, and the reaction time is 1 hour to 100 hours. The amount of the basic catalyst is 0.5 to 30 times the molar amount of the polyamic acid groups, preferably 2 to 20 times the molar amount, and the amount of the acid anhydride is 1 to 50 times the molar amount of the polyamic acid groups. It is preferably 3-fold to 30-fold molar. The imidization rate of the resulting polymer can be controlled by adjusting the amount of catalyst, temperature and reaction time. Since the added catalyst and the like remain in the solution after the imidization reaction of the polyamic acid, the obtained imidized polymer is recovered by the means described below, redissolved in an organic solvent, and the present invention It is preferable to set it as the liquid crystal aligning agent of this.

The polyimide solution obtained as described above is poured into a poor solvent while stirring well to precipitate a polymer. Precipitation is carried out several times, washed with a poor solvent, and dried at room temperature or by heating to obtain a purified polymer powder. The poor solvent is not particularly limited, but includes methanol, 2-propanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene and the like, and methanol, ethanol, 2-propanol, Acetone and the like are preferred.

<Polyimide Precursor - Production of Polyamic Acid Ester>
A polyamic acid ester, which is a polyimide precursor used in the present invention, can be produced by the following production methods (1), (2), or (3).

(1) Production from polyamic acid A polyamic acid ester can be produced by esterifying the polyamic acid produced as described above. Specifically, a polyamic acid and an esterification agent are reacted in the presence of an organic solvent at -20°C to 150°C, preferably 0°C to 50°C, for 30 minutes to 24 hours, preferably 1 hour to 4 hours. can be manufactured by As the esterifying agent, those that can be easily removed by purification are preferable, and include N,N-dimethylformamide dimethylacetal, N,N-dimethylformamide diethylacetal, N,N-dimethylformamide dipropylacetal, and N,N-dimethylformamide. Dineopentyl butyl acetal, N,N-dimethylformamide di-t-butyl acetal, 1-methyl-3-p-tolyltriazene, 1-ethyl-3-p-tolyltriazene, 1-propyl-3-p -tolyltriazene, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride and the like. The amount of the esterifying agent to be added is preferably 2 to 6 molar equivalents per 1 mol of the repeating unit of the polyamic acid.

Examples of organic solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide or 1,3-dimethyl- Imidazolidinones are mentioned. Further, when the polyimide precursor has high solvent solubility, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or formulas [D-1] to [D-3] described later. A solvent represented by can be used. These solvents may be used alone or in combination. Furthermore, even a solvent that does not dissolve the polyimide precursor may be mixed with the solvent and used as long as the generated polyimide precursor does not precipitate. Moreover, water in the solvent inhibits the polymerization reaction and further causes hydrolysis of the produced polyimide precursor, so it is preferable to use a dehydrated and dried solvent.

The solvent used in the above reaction is preferably N,N-dimethylformamide, N-methyl-2-pyrrolidone, or γ-butyrolactone in view of the solubility of the polymer, and these may be used singly or in combination of two or more. good. The concentration at the time of production is preferably 1% by mass to 30% by mass, more preferably 5% by mass to 20% by mass, from the viewpoints that precipitation of the polymer is unlikely to occur and that a high molecular weight product is easily obtained.

(2) Production by reaction of tetracarboxylic acid diester dichloride and diamine Polyamic acid ester can be produced from tetracarboxylic acid diester dichloride and diamine. Specifically, a tetracarboxylic acid diester dichloride and a diamine are mixed in the presence of a base and an organic solvent at -20°C to 150°C, preferably 0°C to 50°C, for 30 minutes to 24 hours, preferably 1 hour to 4 hours. It can be produced by time reaction. Pyridine, triethylamine, 4-dimethylaminopyridine and the like can be used as the base, but pyridine is preferred because the reaction proceeds moderately. The amount of the base to be added is preferably 2 to 4 times the molar amount of the tetracarboxylic acid diester dichloride because it is an amount that can be easily removed and a high molecular weight product can be easily obtained.

The solvent used in the above reaction is preferably N-methyl-2-pyrrolidone or γ-butyrolactone in terms of solubility of the monomer and polymer, and these may be used alone or in combination of two or more. The polymer concentration during production is preferably 1% by mass to 30% by mass, more preferably 5% by mass to 20% by mass, because precipitation of the polymer is less likely to occur and a high molecular weight product can be easily obtained. Moreover, in order to prevent hydrolysis of the tetracarboxylic acid diester dichloride, the solvent used in the production of the polyamic acid ester is preferably dehydrated as much as possible, and is preferably kept in a nitrogen atmosphere to prevent contamination with outside air.

(3) Production from tetracarboxylic acid diester and diamine Polyamic acid ester can be produced by polycondensation of tetracarboxylic acid diester and diamine. Specifically, a tetracarboxylic acid diester and a diamine are mixed in the presence of a condensing agent, a base, and an organic solvent at 0° C. to 150° C., preferably 0° C. to 100° C., for 30 minutes to 24 hours, preferably 3 hours. It can be produced by reacting for 15 hours.

The condensing agent includes triphenyl phosphite, dicyclohexylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, N,N'-carbonyldiimidazole, dimethoxy-1,3,5-triazide Nylmethylmorpholinium, O-(benzotriazol-1-yl)-N,N,N',N'-tetramethyluronium Tetrafluoroborate, O-(benzotriazol-1-yl)-N,N , N′,N′-tetramethyluronium hexafluorophosphate, diphenyl (2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate and the like can be used. The amount of the condensing agent to be added is preferably 2 to 3 times the moles of the tetracarboxylic acid diester.

Tertiary amines such as pyridine and triethylamine can be used as the base. The amount of the base to be added is preferably 2 to 4 times the molar amount of the diamine component, since it is an amount that can be easily removed and a high molecular weight product can be easily obtained. Moreover, in the above reaction, the reaction proceeds efficiently by adding a Lewis acid as an additive. Preferred Lewis acids are lithium halides such as lithium chloride and lithium bromide. The amount of the Lewis acid to be added is preferably 0 to 1.0 times the molar amount of the diamine component. Among the above three methods for producing a polyamic acid ester, the above method (1) or (2) is particularly preferable because a high-molecular-weight polyamic acid ester can be obtained. The solution of the polyamic acid ester obtained as described above is poured into a poor solvent while stirring well to precipitate the polymer. Precipitation is carried out several times, washed with a poor solvent, and dried at room temperature or by heating to obtain a purified polyamic acid ester powder. Poor solvents include, but are not limited to, water, methanol, ethanol, hexane, butyl cellosolve, acetone, and toluene.

In order to produce the polymer of the present invention, the diamine represented by the formula (1) may be used as the diamine in the above production method. The molecular weight of the polyimide precursor or polyimide, which is a polymer containing the liquid crystal aligning agent of the present invention, is such that when a liquid crystal aligning film is obtained from the liquid crystal aligning agent containing the polymer, the coating film (liquid crystal aligning film) is Considering the strength, workability during coating film formation, and uniformity of the coating film, the weight average molecular weight measured by GPC (Gel Permeation Chromatography) method is preferably 2,000 to 500,000. 000 to 300,000, more preferably 10,000 to 100,000.

<Liquid crystal aligning agent>
The liquid crystal aligning agent of the present invention contains a polymer (specific polymer) obtained from a diamine having a structure represented by formula (1). Two or more types of structurally specific polymers may be contained. Moreover, in addition to the specific polymer, other polymers, that is, polymers having no divalent group represented by formula (1) may be contained. Other polymer types include polyamic acids, polyimides, polyamic acid esters, polyesters, polyamides, polyureas, polyorganosiloxanes, cellulose derivatives, polyacetals, polystyrene or its derivatives, poly(styrene-phenylmaleimide) derivatives, poly(meth) ) acrylates and the like. When the liquid crystal aligning agent of the present invention contains other polymer, the ratio of the specific polymer to the total polymer component is preferably 5% by mass or more, and examples thereof include 5% to 95% by mass. .

A liquid crystal aligning agent is used to produce a liquid crystal aligning film, and generally takes the form of a coating liquid from the viewpoint of forming a uniform thin film. Also in the liquid crystal aligning agent of the present invention, the coating liquid preferably contains the above-described polymer component and an organic solvent for dissolving the polymer component. At that time, the concentration of the polymer in the liquid crystal aligning agent can be appropriately changed by setting the thickness of the coating film to be formed. From the point of forming a uniform and defect-free coating film, it is preferably 1% by mass or more, and from the point of storage stability of the solution, it is preferably 10% by mass or less. A particularly preferred polymer concentration is 2% to 8% by weight.

The organic solvent contained in the liquid crystal aligning agent is not particularly limited as long as it uniformly dissolves the polymer component. Specific examples include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylsulfoxide, γ-butyrolactone, 1,3-dimethyl - imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone and the like. Among them, it is preferable to use N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, or γ-butyrolactone.

In addition, the organic solvent contained in the liquid crystal aligning agent is a mixed solvent in which a solvent that improves the coating properties and the surface smoothness of the coating film when applying the liquid crystal aligning agent in addition to the above solvents is used. is common, and such a mixed solvent is suitably used also in the liquid crystal aligning agent of this invention. Specific examples of the organic solvent used in combination are listed below, but are not limited to these examples. For example, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, isopentyl alcohol, tert-pentyl alcohol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, 1-heptanol , 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 1,2- ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentane diol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2-hexanone, 2-heptanone , 4-heptanone, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, 2-(methoxymethoxy) ethanol, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, 2-(hexyloxy) ethanol, furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monobutyl ether, 1-( butoxyethoxy)propanol, propylene glycol monomethyl ether acetate, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol mono Ethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoacetate, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy) ethyl acetate, diethylene glycol Acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate, pyruvic acid ethyl, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, Lactic acid methyl ester, lactic acid ethyl ester, lactic acid n-propyl ester, lactic acid n-butyl ester, lactic acid isoamyl ester, solvents represented by the following formulas [D-1] to [D-3], and the like can be mentioned.

In formula [D-1], D ¹ represents an alkyl group having 1 to 3 carbon atoms, in formula [D-2], D ² represents an alkyl group having 1 to 3 carbon atoms, and formula [D-3] Among them, ^D3 represents an alkyl group having 1 to 4 carbon atoms.

Among them, 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether or Preference is given to using dipropylene glycol dimethyl ether.

The kind and content of such a solvent are appropriately selected according to the liquid crystal aligning agent coating device, coating conditions, coating environment, and the like.

The liquid crystal aligning agent of the present invention may additionally contain components other than the polymer component and the organic solvent as long as the effects of the present invention are not impaired. Such additional components include an adhesion aid for enhancing the adhesion between the liquid crystal alignment film and the substrate and the adhesion between the liquid crystal alignment film and the sealing material, a cross-linking agent for increasing the strength of the liquid crystal alignment film, and liquid crystal alignment. Examples include dielectrics and conductive substances for adjusting the dielectric constant and electrical resistance of the film. Specific examples of these additional components are as disclosed in various known documents related to liquid crystal aligning agents. Examples include the ingredients disclosed on page [0116].

<Liquid crystal alignment film>
The liquid crystal alignment film of the present invention is obtained from the liquid crystal alignment agent. To give an example of a method of obtaining a liquid crystal alignment film from a liquid crystal alignment agent, a liquid crystal alignment agent in the form of a coating liquid is applied to a substrate, dried, and fired to obtain a film that is subjected to a rubbing treatment method or a photo-alignment treatment method. and a method of performing orientation treatment. The substrate to which the liquid crystal aligning agent is applied is not particularly limited as long as it is a highly transparent substrate, and glass substrates, silicon nitride substrates, plastic substrates such as acrylic substrates and polycarbonate substrates, and the like can also be used. In that case, it is preferable to use a substrate on which an ITO electrode or the like for driving the liquid crystal is formed, from the viewpoint of simplification of the process. In addition, in a reflective liquid crystal display element, if only one substrate is used, an opaque material such as a silicon wafer can be used, and in this case, a light-reflecting material such as aluminum can be used for the electrodes.

The method of applying the liquid crystal aligning agent is not particularly limited, but industrially, screen printing, offset printing, flexographic printing, ink jet method and the like are common. Other coating methods include a dipping method, a roll coater method, a slit coater method, a spinner method, and a spray method, and these may be used depending on the purpose. After the liquid crystal aligning agent is applied onto the substrate, the solvent is evaporated by heating means such as a hot plate, a heat circulation type oven, an IR (infrared) type oven, and baked. The drying after applying a liquid crystal aligning agent and a baking process can select arbitrary temperature and time. Usually, in order to sufficiently remove the contained solvent, the conditions include baking at 50° C. to 120° C. for 1 minute to 10 minutes, followed by baking at 150° C. to 300° C. for 5 minutes to 120 minutes. The thickness of the liquid crystal alignment film after baking is not particularly limited, but if it is too thin, the reliability of the liquid crystal display element may be lowered. The liquid crystal alignment film of the present invention is suitable as a liquid crystal alignment film for a horizontal electric field liquid crystal display element such as an IPS system or an FFS system, and is particularly useful as a liquid crystal alignment film for an FFS system liquid crystal display element.

<Liquid crystal display element>
The liquid crystal display element of the present invention is obtained by obtaining a substrate with a liquid crystal aligning film obtained from the liquid crystal aligning agent, producing a liquid crystal cell by a known method, and using the liquid crystal cell. As an example of a method of manufacturing a liquid crystal cell, a liquid crystal display device having a passive matrix structure will be described as an example. A liquid crystal display element having an active matrix structure in which a switching element such as a TFT (Thin Film Transistor) is provided in each pixel portion forming an image display may be used. Specifically, transparent glass substrates are prepared, a common electrode is provided on one substrate, and a segment electrode is provided on the other substrate. These electrodes can be ITO electrodes, for example, and are patterned so as to display a desired image. Next, an insulating film is provided on each substrate so as to cover the common electrodes and the segment electrodes. The insulating film can be, for example, a film made of SiO ₂ —TiO ₂ formed by a sol-gel method. Next, a liquid crystal alignment film is formed on each substrate under the above conditions.

Next, for example, a UV-curing sealing material was placed at a predetermined location on one of the two substrates on which the liquid crystal alignment film was formed, and liquid crystal was placed at several predetermined locations on the surface of the liquid crystal alignment film. After that, the other substrate is attached and pressed so that the liquid crystal alignment film faces each other, and the liquid crystal is spread to the front surface of the liquid crystal alignment film. get a cell In addition, as a step after forming the liquid crystal alignment film on the substrate, when placing a sealing material on a predetermined place on one of the substrates, an opening capable of being filled with the liquid crystal from the outside is provided to allow the liquid crystal to flow. After the substrates are bonded together without disposing, a liquid crystal material is injected into the liquid crystal cell through an opening provided in the sealing material, and then the opening is sealed with an adhesive to obtain a liquid crystal cell. The liquid crystal material may be injected by a vacuum injection method or by a method utilizing capillary action in the atmosphere.

In any of the above methods, in order to secure a space for filling the liquid crystal material in the liquid crystal cell, a columnar projection is provided on one of the substrates, spacers are scattered on one of the substrates, or a sealing material is used. It is preferable to take a means such as mixing a spacer into or combining these.

Examples of the liquid crystal material include nematic liquid crystals and smectic liquid crystals. Among them, nematic liquid crystals are preferable, and either positive liquid crystal materials or negative liquid crystal materials may be used. Next, a polarizing plate is installed. Specifically, it is preferable to attach a pair of polarizing plates to the surfaces of the two substrates opposite to the liquid crystal layer.

In addition, the liquid crystal alignment film and liquid crystal display element of the present invention are not limited to the above description as long as the liquid crystal alignment agent of the present invention is used, and may be prepared by other known methods. good. The process of obtaining a liquid crystal display element from a liquid crystal aligning agent is disclosed in, for example, Japanese Patent Laid-Open No. 2015-135393 (Japanese Patent Laid-Open Publication), page 17 [0074] to page 19 [0081], and many other documents. there is

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these.
The abbreviations of the compounds used in the Examples and Comparative Examples and the method of characterization are as follows.
NMP: N-methyl-2-pyrrolidone BCS: butyl cellosolve GBL: γ-butyl lactone NMP: N-methyl-2-pyrrolidone DA-1-1: compound represented by the following formula DA-1-1 DA-2: below Compound represented by Formula DA-2 DA-3: Compound represented by Formula DA-3 below CA-1: Compound represented by Formula CA-1 below CA-2: Compound represented by Formula CA-2 below Compound

Example 1A
Synthesis of (DA-1-1)

After adding 15.00 g (68.8 mmol) of N-(4-nitrophenyl)maleimide and 300 g of terorahydrofuran (hereinafter referred to as THF) into the flask, the mixture was ice-cooled. Into the mixture was added 3.37 g (33.0 mmol) of N,N'-dimethyl-1,3-propanediamine. Then, after gradually returning to room temperature, the mixture was stirred at room temperature for 1 day. After confirming the completion of the reaction, 200 g of ethyl acetate was added to the reaction mixture and stirred. The obtained crystals were filtered and dried at 50° C. to obtain 11.1 g of the target nitro intermediate (DA-1-1-1) (yield 62%).
1H-NMR (D6-DMSO, δ ppm): 8.37 (d, 4H), 7.62 (d, 4H), 4.15-4.21 (m, 1H), 2.93-3.03 ( m, 2H), 2.80-2.89 (m, 2H), 2.53-2.70 (m, 4H), 2.32 (s, 6H), 1.57-1.67 (m, 2H)

In a nitrogen-substituted flask, DA-1-1-1 11.1 g (20.6 mmol), 5% Pd-C 1 g (STD type, wet product, manufactured by NE Chemcat Co., Ltd.) and N, N- After adding 300 g of dimethylformamide (hereinafter referred to as DMF), the inside of the flask was replaced with hydrogen. The reaction mixture was stirred at room temperature for 3 days under normal hydrogen pressure. After confirming the completion of the reaction, Pd—C was removed from the reaction mixture by filtration, and the filtrate was evaporated under reduced pressure. Chloroform was added to the resulting residue and stirred. The insoluble matter was removed by filtration, and the resulting filtrate was distilled off under reduced pressure to obtain 8.93 g of the target DA-1-1 as a viscous liquid (yield 90%).
1H-NMR (D6-DMSO, δ ppm): 6.79 (d, 4H), 6.55 (d, 4H), 5.274 (brs, 4H), 3.99-4.04 (m, 2H) , 2.79-2.89 (m, 2H), 2.44-2.71 (m, 6H), 3.23 (s, 6H), 1.51-1.61 (m, 2H)

Example 2A
Synthesis of (DA-1-2)

After adding 0.1246 g (0.662 mmol) of N-(4-aminophenyl)maleimide and 3 g of THF into the flask, the mixture was ice-cooled. Into the mixture was added 0.0285 g (0.331 mmol) of piperazine. Then, after gradually returning to room temperature, the mixture was stirred at room temperature for 3 days. After confirming that the reaction was completed, the precipitated crystals were filtered and washed with diisopropyl ether (hereinafter, IPA). The resulting crystals were dried at 50° C. to obtain 0.067 g of the desired DA-1-2 (yield 47%).
1H-NMR (D6-DMSO, δ ppm): 6.82 (d, 4H), 6.59 (d, 4H), 5.30 (brs, 4H), 3.92-3.98 (m, 2H) , 2.70-2.95 (m, 8H), 2.40-55 (m, 2H)

Example 3A
Synthesis of (DA-1-3)

After adding 2.90 g (15.4 mmol) of N-(4-aminophenyl)maleimide and 30 g of terorahydrofuran (hereinafter referred to as THF) into the flask, the mixture was ice-cooled. Into the mixture was added 1.00 g (7.34 mmol) of 4-(aminomethyl)benzylamine. Then, after gradually returning to room temperature, the mixture was stirred at room temperature for 3 hours. After confirming the completion of the reaction, the reaction mixture was cooled again and the precipitated crystals were filtered. The obtained crystals were dried at 45° C. under reduced pressure to obtain 1.59 g of the objective compound (DA-1-3) as yellow crystals (yield 42%).
1H-NMR (D6-DMSO, δ ppm): 7.32 (s, 4H), 6.84 (d, 4H), 6.59 (d, 4H), 5.31 (brs, 4H), 3.82 -3.95 (m, 4H), 3.74-3.82 (m, 2H), 2.91-3.01 (m, 2H), 2.94 (brs, 2H), 2.53-2 .56 (m, 1H), 2.48-2.51 (m, 1H)

[Viscosity measurement]
The viscosity of the polyamic acid solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL and a cone rotor TE-1 (1°34′, R24).

[Example 1]
After DA-1-1 (3.34 g, 7 mmol) was added to a 50 ml four-necked flask equipped with a stirrer and a nitrogen inlet tube, 31.5 g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. While stirring this diamine solution, CA-1 (1.43 g, 6.58 mmol) was added, and after adding 3.5 g of NMP, the polyamic acid solution (PAA- 1) was obtained. The viscosity of this polyamic acid solution at 25° C. was 270 mPa·s.

[Example 2]
DA-1-1 (3.34 g, 7 mmol) was added to a 50 ml four-necked flask equipped with a stirrer and a nitrogen inlet tube, and then 31.1 g of NMP was added and dissolved with stirring while supplying nitrogen. While stirring this diamine solution, CA-1 (0.61 g, 2.8 mmol) and CA-2 (0.75 g, 3.9 mmol) were added. A polyamic acid solution (PAA-2) was obtained by stirring for 12 hours. The viscosity of this polyamic acid solution at 25° C. was 280 mPa·s.

[Comparative Example 1]
DA-2 (5.73 g, 20 mmol) was added to a 100 ml four-necked flask equipped with a stirrer and a nitrogen inlet tube, 65.1 g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. After adding CA-1 (4.14 g, 19 mmol) while stirring this diamine solution, 7.2 g of NMP was added, and the polyamic acid solution (PAA-3 ). The viscosity of this polyamic acid solution at 25° C. was 500 mPa·s.

[Comparative Example 2]
After DA-3 (1.98 g, 10 mmol) was added to a 50 ml four-necked flask equipped with a stirrer and a nitrogen inlet tube, 26.0 g of NMP was added and dissolved by stirring while supplying nitrogen. While stirring this diamine solution, CA-1 (0.87 g, 4.0 mmol) and CA-2 (1.08 g, 5.5 mmol) were added, and after adding 2.9 g of NMP, the mixture was further heated to 50°C. A polyamic acid solution (PAA-4) was obtained by stirring for 12 hours. The viscosity of this polyamic acid solution at 25° C. was 300 mPa·s.

[Example 3]
7.5 g of the polyamic acid solution (PAA-1) obtained in Example 1 was taken and stirred while containing 5.6 g of NMP, 6.0 g of BCS, and 1% by weight of 3-aminopropyltriethoxysilane. 0.9 g of NMP solution was added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (Q-1).

[Example 4]
7.5 g of the polyamic acid solution (PAA-2) obtained in Example 2 was taken and stirred while containing 5.6 g of NMP, 6.0 g of BCS, and 1% by weight of 3-aminopropyltriethoxysilane. 0.9 g of NMP solution was added, and the mixture was further stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (Q-2).

[Comparative Example 3]
7.5 g of the polyamic acid solution (PAA-3) obtained in Comparative Example 1 was taken and stirred while containing 5.6 g of NMP, 6.0 g of BCS, and 1% by weight of 3-aminopropyltriethoxysilane. 0.9 g of NMP solution was added, and the mixture was stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (Q-3).

[Comparative Example 4]
7.5 g of the polyamic acid solution (PAA-4) obtained in Comparative Example 2 was taken and stirred while containing 5.6 g of NMP, 6.0 g of BCS, and 1% by weight of 3-aminopropyltriethoxysilane. 0.9 g of NMP solution was added, and the mixture was further stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent (Q-4).

[Production of liquid crystal cell for ion density measurement]
After filtering the liquid crystal aligning agent with a 1.0 μm filter, a substrate with electrodes (a glass substrate with a size of 30 mm wide × 40 mm long and a thickness of 1.1 mm. The electrodes are rectangular with a width of 10 mm × length of 40 mm, It was applied to an ITO electrode having a thickness of 35 nm) by spin coating. After drying on a hot plate at 50° C. for 5 minutes, baking was performed in an IR oven at 230° C. for 20 minutes to form a coating film having a thickness of 100 nm to obtain a substrate with a liquid crystal alignment film. After rubbing this liquid crystal alignment film with a rayon cloth (Yoshikawa Kako YA-20R) (roller diameter: 120 mm, roller rotation speed: 1000 rpm, moving speed: 20 mm / sec, pushing length: 0.4 mm), in pure water After washing by ultrasonic irradiation for 1 minute, water droplets were removed by air blowing, the substrate was dried at 80° C. for 15 minutes to obtain a substrate with a liquid crystal alignment film.

Prepare two substrates with the above liquid crystal alignment film, sprinkle a 4 μm spacer on the surface of one of the liquid crystal alignment films, then print a sealing material from above, and rub the other substrate in the opposite direction. After laminating in such a way that the directions and film surfaces face each other, the sealing material is cured to prepare an empty cell. MLC-3019 (manufactured by Merck Ltd.) was injected into this empty cell by a vacuum injection method, and the injection port was sealed to obtain a liquid crystal cell. After that, the obtained liquid crystal cell was heated at 120° C. for 1 hour and allowed to stand at 23° C. overnight to obtain a liquid crystal cell for ion density measurement.

[Ion density measurement]
The ion density was measured for the liquid crystal cell produced by the method described in [Preparation of Liquid Crystal Cell for Ion Density Measurement] above. In the ion density measurement, the ion density was measured when a triangular wave with a voltage of ±10 V and a frequency of 0.01 Hz was applied to the liquid crystal cell. The measurement temperature was 60°C. A 6256-type liquid crystal physical property evaluation device manufactured by Toyo Technica Co., Ltd. was used as a measuring device. The ion density was measured after the cell was fabricated and after aging the fabricated cell under high temperature and high humidity conditions of 60° C. and 90% for 120 hours.

[Production of liquid crystal display element]
First, a substrate with electrodes was prepared. The substrate is a glass substrate with a size of 30 mm×35 mm and a thickness of 0.7 mm. An IZO electrode having a solid pattern is formed as a first layer on the substrate to form a counter electrode. A SiN (silicon nitride) film formed by a CVD method is formed as a second layer on the counter electrode of the first layer. The SiN film of the second layer has a film thickness of 500 nm and functions as an interlayer insulating film. On the SiN film of the second layer, a comb-shaped pixel electrode formed by patterning an IZO film is arranged as a third layer to form two pixels, a first pixel and a second pixel. ing. The size of each pixel is about 10 mm long and about 5 mm wide. 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 configured by arranging a plurality of dogleg-shaped electrode elements bent at the central portion, as in the drawing described in Japanese Patent Application Laid-Open No. 2014-77845. . The width of each electrode element in the lateral direction is 3 μm, and the interval between electrode elements is 6 μm. Since the pixel electrode that forms each pixel is configured by arranging a plurality of bent dogleg-shaped electrode elements in the central portion, the shape of each pixel is not rectangular, but in the central portion like the electrode elements. It has a curved shape resembling a bold character. Each pixel is vertically divided by the curved portion in the center, and has a first region above the curved portion and a second region below the curved portion.

Comparing the first region and the second region of each pixel, the formation direction of the electrode elements of the pixel electrodes constituting them is different. That is, when the rubbing direction of the liquid crystal alignment film, which will be described later, is used as a reference, the electrode element of the pixel electrode is formed to form an angle of +10° (clockwise) in the first region of the pixel, and the pixel in the second region of the pixel. The electrode elements of the electrode are formed at an angle of -10° (clockwise). That is, in the first region and the second region of each pixel, the directions of the rotation operation (in-plane switching) of the liquid crystal induced by the voltage application between the pixel electrode and the counter electrode in the plane of the substrate are mutually different. It is configured to be in the opposite direction.

Next, after filtering the obtained liquid crystal aligning agent with a 1.0 μm filter, the prepared substrate with electrodes and a columnar spacer having a height of 4 μm on which an ITO film is formed on the back surface as a counter substrate. was spin-coated onto each of the glass substrates with Then, after drying on a hot plate at 80° C. for 5 minutes, it was baked at 230° C. for 20 minutes to obtain a polyimide film on each substrate as a coating film having a thickness of 60 nm. After rubbing the polyimide film with a rayon cloth in a predetermined rubbing direction (roll diameter 120 mm, rotation speed 500 rpm, moving speed 30 mm/sec, pushing amount 0.3 mm), ultrasonic irradiation in pure water for 1 minute. and dried at 80° C. for 10 minutes.

After that, using the above two types of substrates with liquid crystal alignment films, they were combined so that their rubbing directions were antiparallel. made. Liquid crystal (MLC-3019, manufactured by Merck & Co., Ltd.) was vacuum-injected into this empty cell at normal temperature, and then the injection port was sealed to form an anti-parallel aligned liquid crystal cell. The obtained liquid crystal cell constitutes an FFS mode liquid crystal display element. After that, the obtained liquid crystal cell was heated at 120° C. for 1 hour and allowed to stand overnight before being used for each evaluation.

[Evaluation of stability of liquid crystal alignment]
Using this liquid crystal cell, an AC voltage of 10 VPP was applied at a frequency of 30 Hz for 168 hours in a constant temperature environment of 60°C. After that, the pixel electrode and the counter electrode of the liquid crystal cell were short-circuited and left at room temperature for one day. After standing, the liquid crystal cell was placed between two polarizing plates arranged so that the polarizing axes were perpendicular to each other, and the backlight was turned on with no voltage applied so that the brightness of the transmitted light was minimized. The arrangement angle of the liquid crystal cell was adjusted. Then, the rotation angle when the liquid crystal cell was rotated from the angle at which the second region of the first pixel was the darkest to the angle at which the first region was the darkest was calculated as the angle Δ. Similarly, for the second pixel, the second region and the first region were compared to calculate a similar angle Δ. Then, the average value of the angle Δ values of the first pixel and the second pixel was calculated as the angle Δ of the liquid crystal cell. A liquid crystal cell having an angle Δ of 0.15° or less was evaluated as good, and a liquid crystal cell having an angle Δ of more than 0.15° was evaluated as poor.

[Relaxation characteristics of accumulated charges]
The liquid crystal cell is placed between two polarizing plates arranged so that the polarization axes are orthogonal, and the pixel electrode and the counter electrode are short-circuited to the same potential. The backlight was illuminated, and the angle of the liquid crystal cell was adjusted so that the brightness of the light transmitted through the LED backlight measured on the two polarizing plates was minimized. Next, while applying a rectangular wave with a frequency of 30 Hz to this liquid crystal cell, the VT characteristic (voltage-transmittance characteristic) was measured at a temperature of 23° C., and an AC voltage at which the relative transmittance was 23% was applied. Calculated. Since this AC voltage corresponds to a region in which the change in luminance with respect to voltage is large, it is convenient for evaluating accumulated charges via luminance.

Next, after applying a rectangular wave with a frequency of 30 Hz at an AC voltage with a relative transmittance of 23% for 5 minutes, a DC voltage of +1.0 V was superimposed and driven for 30 minutes. After that, the DC voltage was turned off, and only the AC voltage with the relative transmittance of 23% and the rectangular wave with the frequency of 30 Hz was applied for 30 minutes. The faster the relaxation of the accumulated charge, the faster the charge is accumulated in the liquid crystal cell when the DC voltage is superimposed. It was evaluated by the time required to decrease from 23% to 23%. The shorter this time is, the better the relaxation characteristic of accumulated charge is.

<Examples 5-6 and Comparative Examples 5-6>
Using the liquid crystal aligning agents Q-1 and Q-2 obtained in Examples 3 and 4 and the liquid crystal aligning agents Q3 and Q4 obtained in Comparative Examples 3 and 4, ion density measurement, liquid crystal alignment stability evaluation and We evaluated the relaxation characteristics of the accumulated charges. Table 1 shows the results.

The liquid crystal alignment film of the present invention can suppress the ion density in the liquid crystal display element to a low level and rapidly relax the accumulated electric charge, especially in the liquid crystal display element of the IPS driving method or the FFS driving method that requires rubbing treatment. Furthermore, since the deviation between the rubbing direction and the alignment direction of the liquid crystal can be suppressed, display performance excellent in afterimage characteristics and contrast can be obtained. Therefore, it is particularly useful as a liquid crystal alignment film used in IPS drive system or FFS drive system liquid crystal display elements, multifunctional mobile phones (smartphones), tablet personal computers, liquid crystal televisions, and the like.

Claims (9)

A diamine having a structure represented by the following formula (1).

R ¹ represents a hydrogen atom, a linear or branched alkyl group having 1 to 5 carbon atoms, or an aryl group, and two R ^1s on the same maleimide ring may be the same or different; Two R ¹ may together form an alkylene having 3 to 6 carbon atoms, and W ² is a divalent organic group represented by the following formulas [W2-1] to [W2-152]. W ¹ represents a single bond or carbonyl, L ¹ is a linear alkylene group having 1 to 20 carbon atoms, a branched alkylene group having 3 to 20 carbon atoms, a cyclic alkylene group having 3 to 20 carbon atoms, a phenylene group and a heterocyclic group, or a group formed by bonding a plurality of such divalent groups, and a phenylene group and a heterocyclic group are each independently an alkyl group, an alkoxy group, a haloalkyl group, or a haloalkoxy group , may be substituted with one or more substituents that are the same or different selected from a halogen group and a cyano group, and the bond between the divalent groups is a single bond, an ester bond, an amide bond, a urea bond, an ether At least one selected from a bond, a thioether bond, an amino bond, and a carbonyl, and when there are multiple divalent groups, the divalent groups may be the same or different, and when there are multiple bonds , the bonds may be the same or different, and R represents a hydrogen atom , a straight-chain alkyl group having 1 to 3 carbon atoms, or a protecting group that undergoes an elimination reaction by heat and replaces a hydrogen atom , and the protecting group is , 1,1-dimethyl-2-chloroethoxycarbonyl group, 1,1-dimethyl-2-cyanoethoxycarbonyl group, and tert-butoxycarbonyl group; One R may together form an alkylene having 1 to 6 carbon atoms, and both or either one of two R may be bonded to L ¹ .

2. The diamine of claim ¹ , wherein said W1 represents a single bond. W ² is selected from W ² -7 , W ² -20, W ² -21, W ² -23 to W ² -26, W ² -39 to W ² -43, W ² -51 to W ² -71 3. The diamine of claim 1 or 2, wherein the diamine is

A polymer obtained by using the diamine according to any one of claims 1 to 3. 5. The polymer according to claim 4, which is at least one selected from a polyimide precursor containing a structural unit represented by the following formula (3), and a polyimide which is an imidized product thereof.

X ¹ represents a tetravalent organic group derived from a tetracarboxylic acid derivative, Y ¹ represents a divalent organic group derived from a diamine containing the structure of formula (1), and R ⁴ represents a hydrogen atom or 1 carbon atom. represents an alkyl group of ∼5. 6. The polymer according to claim 5, wherein the structure of ^X1 in formula (3) represents at least one selected from the following structures.

6. The polymer according to claim 5, which is at least one selected from a polyimide precursor further containing a structural unit represented by the following formula (4), and a polyimide which is an imidized product thereof.

In formula (4), ^X2 represents a tetravalent organic group derived from a tetracarboxylic acid derivative, and ^Y2 represents a divalent organic group derived from a diamine that does not contain the structure of formula (1) in the main chain direction. Each R ¹⁴ independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and each R ¹⁵ independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. The polymer according to claim 7, wherein ^Y2 is represented by the following formula (11).

In formula (11), R ³² represents a single bond or a divalent organic group, R ³³ represents a structure represented by —(CH ₂ ) _r —, r represents an integer of 2 to 10, and Any —CH ₂ — may be replaced with an ether, ester, amide, urea, or carbamate bond under the condition that they are not adjacent to each other. ^R34 represents a single bond or a divalent organic group. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group. 7. The polymer according to claim 5 or 6, wherein the structural unit represented by formula (3) accounts for 10 mol% or more of all structural units.