TWI776209B - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

The present invention provides a liquid crystal alignment agent with good residual DC properties, a liquid crystal alignment film, a liquid crystal display element, and a method for manufacturing the liquid crystal display element.

A liquid crystal alignment agent, which contains the following components (A), (B), and an organic solvent; it is used for a liquid crystal display element, and the liquid crystal display element is formed by irradiating a liquid crystal cell with light, and the liquid crystal cell will A liquid crystal aligning agent is coated on the conductive film having a pair of substrates of the conductive film and heated to form a substrate with a coating film, and the coating films are arranged opposite to each other through the liquid crystal layer.

(A) Component: at least one polymer selected from the group consisting of a polyimide precursor having a side chain that aligns liquid crystals vertically, and a polyimide that is an imide of the polyimide precursor.

(B) Component: selected from a polyimide precursor including a reaction product of a tetracarboxylic dianhydride component and a diamine component selected from tetracarboxylic dianhydrides of the following formulas (1) and (1'), and at least one polymer of the polyimide group of the polyimide precursor of the polyimide precursor; however, when the component (B) has a side chain for vertically aligning the liquid crystal, it can be combined with the component (A) for the same polymer.

(j、k為0或1，x、y為單鍵、羰基等。)

(j, k are 0 or 1, x, y are single bond, carbonyl, etc.)

Description

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

The present invention relates to a liquid crystal aligning agent, a liquid crystal display element, and a manufacturing method of the liquid crystal display element which can be used in the manufacture of a liquid crystal display element of a vertical alignment method produced by irradiating a liquid crystal molecule with ultraviolet rays.

Among the liquid crystal display elements in which the liquid crystal molecules that are vertically aligned to the substrate are responded to by an electric field (also called the vertical alignment (VA) method), the manufacturing process includes applying a voltage to the liquid crystal molecules while simultaneously The steps of irradiating ultraviolet rays.

It is known to add a photopolymerizable compound to the liquid crystal composition in advance, and use it together with a vertical alignment film such as polyimide, and to apply a voltage to the liquid crystal cell while irradiating ultraviolet rays, On the other hand, a PSA (Polymer Sustained Alignment) element has a fast response speed of liquid crystal (refer to Patent Document 1 and Non-Patent Document 1).

Usually, the tilt direction of the liquid crystal molecules responding to the electric field is controlled by protrusions provided on the substrate, slits provided on the display electrodes, or the like. exist When a photopolymerizable compound is added to the liquid crystal composition, and a voltage is applied to the liquid crystal cell while irradiating ultraviolet rays at the same time, since the polymer structure that has memorized the tilt direction of the liquid crystal molecules is formed on the liquid crystal alignment film, it is generally considered that it is in the same Compared with the method of controlling the tilt direction of liquid crystal molecules by protrusions or slits, the response speed of the liquid crystal display element becomes faster.

On the other hand, it has been reported that even by adding a photopolymerizable compound to a liquid crystal alignment film instead of a liquid crystal composition, the response speed of a liquid crystal display element becomes faster (SC-PVA type liquid crystal display) (see non-liquid crystal display). Patent Document 2). In addition, in recent years, higher-speed response of PSA-type liquid crystal panels has been studied, and as this technology, an attempt has been made to combine a monofunctional liquid crystalline compound having any one or more of an alkenyl group and a fluoroalkenyl group (hereinafter, also referred to as a fluoroalkenyl group). referred to as "alkenyl-based liquid crystal") into the liquid crystal composition (refer to Patent Documents 2 to 5). However, when an alkenyl-based liquid crystal is introduced into a liquid crystal composition, the reliability is lowered (see Patent Documents 6 to 9), and the voltage holding ratio and the DC charge storage characteristics (residual DC characteristics) tend to be deteriorated.

In particular, the deterioration of the residual DC characteristics causes burn-in which causes deterioration of the display characteristics (afterimage) of the liquid crystal display element. As a method for improving residual DC so far, formation of a carboxyl group and a salt of a nitrogen-containing aromatic heterocycle or promotion of charge transfer due to electrostatic interaction called hydrogen bonding are known. However, there is little knowledge about the method of improving the residual DC in the case of using an alkenyl-based liquid crystal (refer to Patent Documents 10 to 12).

[Prior Art Literature]

[Patent Documents]

[Patent Document 1] Japanese Patent Application Laid-Open No. 2003-307720

[Patent Document 2] International Publication No. 2009/050869

[Patent Document 3] Japanese Patent Application Laid-Open No. 2010-285499

[Patent Document 4] Japanese Patent Application Laid-Open No. 9-104644

[Patent Document 5] Japanese Patent Application Laid-Open No. 6-108053

[Patent Document 6] Specification of European Patent No. 0474062

[Patent Document 7] US Patent No. 6,066,268

[Patent Document 8] Japanese Patent Application Laid-Open No. 2014-240486

[Patent Document 9] Japanese Patent Application Laid-Open No. 2014-224260

[Patent Document 10] Japanese Patent Application Laid-Open No. 9-316200

[Patent Document 11] Japanese Patent Application Laid-Open No. 10-104633

[Patent Document 12] Japanese Patent Application Laid-Open No. 8-76128

[Non-patent literature]

[Non-Patent Document 1] K. Hanaoka, SID 04 DIGEST, P.1200-1202

[Non-Patent Document 2] K.H Y.-J. Lee, SID 09 DIGEST, P.666-668

An object of the present invention is to provide a method that enables vertical alignment The response speed of the liquid crystal display element of the formula is improved, and the electrical characteristics and residual DC characteristics of the obtained liquid crystal display element can be obtained, especially the residual DC characteristics of the liquid crystal composition containing the alkenyl liquid crystal can be changed into a good liquid crystal An alignment agent, a liquid crystal alignment film, a liquid crystal display element, and a manufacturing method of the liquid crystal display element.

In order to solve the above-mentioned problems, the inventors of the present invention have found out a method for solving the above-mentioned problems as a result of careful studies, and have completed the present invention having the following gist.

1. A liquid crystal alignment agent comprising the following components (A), (B), and an organic solvent; it is for a liquid crystal display element, and the liquid crystal display element is formed by irradiating a liquid crystal cell with light, and the liquid crystal The unit applies a liquid crystal aligning agent to the conductive film of a pair of substrates with a conductive film and heats it to form a substrate with a coating film, and the above-mentioned coating films are arranged opposite to each other through the liquid crystal layer;

(A) Component: at least one polymer selected from the group consisting of a polyimide precursor having a side chain that aligns liquid crystals vertically, and a polyimide that is an imide of the polyimide precursor.

(B) Component: selected from a polyimide precursor including a reaction product of a tetracarboxylic dianhydride component and a diamine component selected from tetracarboxylic dianhydrides of the following formulas (1) and (1'), and at least one polymer grouped by the polyimide of the polyimide precursor of the polyimide. However, when the component (B) has a side chain for vertically aligning the liquid crystal, the same polymerization as the component (A) is possible. thing.

(式中，j及k係各自獨立為0或1，x及y係各自獨立為單鍵、羰基、酯、伸苯基、磺醯基或醯胺基。)

(In the formula, j and k are each independently 0 or 1, and x and y are each independently a single bond, a carbonyl group, an ester, a phenylene group, a sulfonyl group or an amido group.)

2. The liquid crystal aligning agent according to the above 1, wherein the liquid crystal layer in the liquid crystal display element is a liquid crystal layer containing a liquid crystal compound having an alkenyl liquid crystal.

3. The liquid crystal aligning agent according to the above 1 or 2, wherein the content ratio of the (A) component and the (B) component is (A) component under the mass ratio: (B) component=X: (10-X) (X= 1~9).

4. The liquid crystal aligning agent according to any one of the above 1 to 3, wherein the side chain of the component (A) for vertically aligning the liquid crystal is represented by the following formula (a).

(l、m及n係各自獨立表示0或1之整數，R¹表示碳數2~6之伸烷基、-O-、-COO-、-OCO-、-NHCO-、-CONH-、或碳數1~3之伸烷基-醚基，R²、R³、及R⁴係各自獨立表示伸苯基、含氟伸苯基或環伸烷基，R⁵表示氫原子、碳 數2~24之烷基、碳數2~24之含氟烷基、一價之芳香環、一價之脂肪族環、一價之雜環，或由此等所構成之一價之環狀取代物。)

(l, m and n are integers each independently representing 0 or 1, R ¹ represents an alkylene group having 2 to 6 carbon atoms, -O-, -COO-, -OCO-, -NHCO-, -CONH-, or An alkylene-ether group having 1 to 3 carbon atoms, R ² , R ³ , and R ⁴ each independently represent a phenylene group, a fluorine-containing phenylene group, or a cycloalkylene group, and R ⁵ represents a hydrogen atom and a carbon number of 2 Alkyl of ~24, fluorine-containing alkyl of 2 to 24 carbon atoms, monovalent aromatic ring, monovalent aliphatic ring, monovalent heterocyclic ring, or monovalent cyclic substituent composed of these .)

5. A liquid crystal alignment film having a film thickness of 5 to 300 nm obtained from the liquid crystal alignment agent according to any one of 1 to 4 above.

6. A liquid crystal display element comprising the liquid crystal alignment film according to 5 above.

7. A method for manufacturing a liquid crystal display element, characterized by comprising: applying a liquid crystal aligning agent containing the following components (A), (B) and an organic solvent, respectively, on the conductive layer having a pair of substrates with a conductive film On the film, the first step of forming a coating film by heating it; the second step of constructing a liquid crystal cell by arranging the above-mentioned coating films opposite to each other through a liquid crystal layer between a pair of substrates to form the above-mentioned coating film; for the above-mentioned The liquid crystal cell performs the third step of light irradiation.

(A) Component: at least one polymer selected from the group consisting of a polyimide precursor having a side chain for vertically aligning a liquid crystal, and a polyimide that is an imide compound of the polyimide precursor.

(B) Component: selected from a polyamide containing at least one tetracarboxylic dianhydride selected from the group of the following formulae (1) and (1'), a reaction product of a tetracarboxylic dianhydride component and a diamine An amine precursor, and at least one polymer grouped by the polyimide of the polyimide precursor of the polyimide precursor. However, when the component (B) has a side chain for vertically aligning the liquid crystal, the same polymer as the component (A) may be used.

(式中，j、k、x及y係如以上所述。)

(In the formula, j, k, x and y are as described above.)

8. The method for producing a liquid crystal display element according to 7 above, wherein the liquid crystal layer is a liquid crystal layer containing a liquid crystal compound having an alkenyl liquid crystal.

9. The method for manufacturing a liquid crystal display element according to the above 7 or 8, wherein the irradiation amount of the ultraviolet rays is 1-50 J/cm ² .

10. The method for manufacturing a liquid crystal display element according to any one of the above 7 to 9, wherein the liquid crystal display element is a vertical alignment type display element.

According to the present invention, it is possible to provide a liquid crystal display element of a vertical alignment method with a high response speed of liquid crystal and less residual DC.

The liquid crystal aligning agent used in the manufacturing method of this invention is the liquid crystal aligning agent for vertical alignment type liquid crystal display elements containing the said (A) component, (B) component, and an organic solvent. However, the said (B) component may be the same polymer as (A) component.

Furthermore, in the present invention, the liquid crystal alignment agent refers to a solution for making a liquid crystal alignment film, the liquid crystal alignment film refers to a film for aligning liquid crystals in a predetermined direction, and in the present invention, it is a film for aligning the liquid crystal in a vertical direction.

[Ingredient (A)]

The liquid crystal aligning agent of the present invention contains, as component (A), a polyimide selected from the group consisting of a polyimide precursor having a side chain for vertically aligning a liquid crystal, and an imide of the polyimide precursor. At least one polymer of a group of amines.

<Side chain for vertical alignment of liquid crystal>

The side chain for vertically aligning the liquid crystal is not limited as long as the structure can align the liquid crystal vertically with respect to the substrate. For example, a long-chain alkyl group, a group having a ring structure or a branched structure in the middle of the long-chain alkyl group, a steroid group, a group in which a part or all of the hydrogen atoms of these groups are substituted with a fluorine atom, etc. are mentioned. The side chain system for vertically aligning the liquid crystal can be directly bonded to the main chain of polyamide or polyimide, and can also be bonded through an appropriate bonding group. As a side chain which aligns a liquid crystal vertically, the thing represented by following formula (a) is mentioned, for example.

(式(a)中，l、m及n係各自獨立表示0或1之整數， R¹表示碳數2~6之伸烷基、-O-、-COO-、-OCO-、-NHCO-、-CONH-、或碳數1~3之伸烷基-醚基，R²、R³、及R⁴係各自獨立表示伸苯基、含氟伸苯基或環伸烷基，R⁵表示氫原子、碳數2~24之烷基、碳數2~24之含氟烷基、一價之芳香環、一價之脂肪族環、一價之雜環，或由此等所構成之一價之大環狀取代物。)

(In formula (a), l, m, and n each independently represent an integer of 0 or 1, and R ¹ represents an alkylene group having 2 to 6 carbon atoms, -O-, -COO-, -OCO-, -NHCO- , -CONH-, or alkylene-ether group with 1 to 3 carbon atoms, R ² , R ³ , and R ⁴ each independently represent phenylene, fluorine-containing phenylene or cycloalkylene, and R ⁵ represents Hydrogen atom, alkyl group with 2 to 24 carbon atoms, fluorine-containing alkyl group with 2 to 24 carbon atoms, monovalent aromatic ring, monovalent aliphatic ring, monovalent heterocyclic ring, or one of them valence macrocyclic substitution.)

Furthermore, from the viewpoint of ease of synthesis, R ¹ in the above formula (a) is preferably -O-, -COO-, -CONH-, or an alkylene-ether group having 1 to 3 carbon atoms.

In addition, from the viewpoints of ease of synthesis and ability to vertically align liquid crystals, R ² , R ³ and R ⁴ in formula (a) are represented by l, m, n, R ² , R ³ and ^The combination of R4 is preferred.

When at least one of l, m and n is 1, R in ^formula (a) is preferably a hydrogen atom, an alkyl group having 2 to 14 carbon atoms, or a fluorine-containing alkyl group having 2 to 14 carbon atoms, more preferably A hydrogen atom, an alkyl group having 2 to 12 carbon atoms, or a fluorine-containing alkyl group having 2 to 12 carbon atoms. In addition, when l, m and n are all 0, R ⁵ is preferably an alkyl group having 12 to 22 carbon atoms, a fluorine-containing alkyl group having 12 to 22 carbon atoms, a monovalent aromatic ring, or a monovalent aliphatic ring. , a monovalent heterocyclic ring, or a monovalent macrocyclic substituent formed by these, more preferably an alkyl group having 12 to 20 carbon atoms or a fluorine-containing alkyl group having 12 to 20 carbon atoms.

The content of the side chain in the polyimide or polyimide precursor used in the present invention to align the liquid crystal vertically is not particularly limited as long as the liquid crystal alignment film can align the liquid crystal vertically. However, in a liquid crystal display element with a liquid crystal alignment film, if the response speed of the liquid crystal is to be faster, the content of the side chain of the vertical alignment of the liquid crystal is preferably as small as possible within the range that can maintain the vertical alignment.

Also, the ability of a polymer having a side chain to align the liquid crystal vertically is different depending on the configuration of the side chain to align the liquid crystal vertically. Generally speaking, when the content of the side chain for vertically aligning liquid crystal becomes too large, the ability to vertically align liquid crystal increases, and when it becomes small, it decreases. In addition, the side chain having a cyclic structure tends to have a higher ability to align the liquid crystal vertically than the side chain having no cyclic structure.

<The manufacturing method of (A) component>

Production of such at least one polymer selected from the group consisting of a polyimide precursor having a side chain for vertically aligning a liquid crystal, and a polyimide obtained by imidizing the polyimide precursor That is, the method of (A) component is not specifically limited. For example, in the method of obtaining a polyamic acid by the reaction of a diamine and a tetracarboxylic dianhydride, what is necessary is just to copolymerize the diamine which has a side chain which aligns a liquid crystal vertically, and a tetracarboxylic dianhydride.

Examples of the diamine having a side chain that aligns liquid crystals vertically include a long-chain alkyl group, a group having a ring structure or a branched structure in the middle of the long-chain alkyl group, a steroid group, and a combination of hydrogen atoms of these groups. The group etc. which are partially or totally substituted by a fluorine atom are used as the diamine of the side chain, for example, the diamine which has the side chain represented by the said formula (a). More specifically, for example, diamines represented by the following formulae (2), (3), (4) and (5) are mentioned, but not limited thereto.

(式(2)中之l、m、n、及R¹~R⁵之定義係與上述式(a)相同。)

(The definitions of l, m, n, and R ¹ to R ⁵ in formula (2) are the same as those of formula (a) above.)

(式(3)及式(4)中，A₁₀表示-COO-、-OCO-、-CONH-、-NHCO-、-CH₂-、-O-、-CO-、或-NH-，A₁₁表示單鍵或伸苯基，a表示與上述式(a)所表示之使液晶垂直配向之側鏈為相同之構造，a’係表示從與上述式(a)所表示之 使液晶垂直配向之側鏈為相同之構造中去除一個氫原子等之構造之二價之基。)

(In formula (3) and formula (4), A ₁₀ represents -COO-, -OCO-, -CONH-, -NHCO-, -CH ₂ -, -O-, -CO-, or -NH-, A ₁₁ represents a single bond or an extended phenyl group, a represents the same structure as the side chain represented by the above formula (a) for vertically aligning the liquid crystal, and a' represents the vertical alignment of the liquid crystal from the one represented by the above formula (a). The side chain is the divalent base of the structure in which one hydrogen atom is removed in the same structure.)

(式(5)中，A₁₄為可被氟原子所取代之碳數3~20之烷基，A₁₅為1,4環伸已基或1,4-伸苯基，A₁₆為氧原子或-COO-＊(但，附加「＊」之鍵結處係與A₁₅結合)，A₁₇為氧原子或-COO-＊(但，附加「＊」之鍵結處係與(CH₂)a₂結合)。又，a₁為0、或1之整數，a₂為2~10之整數，a₃為0、或1之整數。)

(In formula (5), A ₁₄ is an alkyl group having 3 to 20 carbon atoms that can be substituted by a fluorine atom, A ₁₅ is a 1,4-cyclohexylene group or a 1,4-phenylene group, A ₁₆ is an oxygen atom Or -COO-* (but, the bond with "*" is combined with A ₁₅ ), A ₁₇ is an oxygen atom or -COO-* (but, the bond with "*" is with (CH ₂ ) a ₂ is combined). Also, a ₁ is an integer of 0 or 1, a ₂ is an integer of 2 to 10, and a ₃ is an integer of 0 or 1.)

The binding positions of the two amine groups (-NH ₂ ) in the formula (2) are not limited. Specifically, with respect to the binding group of the side chain, the positions of 2, 3, 2, 4, 2, 5, 2, 6, 3, 4, 3,5 position. Among them, the position of 2,4, the position of 2,5, or the position of 3,5 is preferable from the viewpoint of the reactivity at the time of synthesizing the polyamic acid. When considering the ease of synthesizing diamine, the position of 2,4 or the position of 3,5 is more preferable.

As a specific structure of Formula (2), although the diamine represented by following formula [A-1] - Formula [A-24] can be illustrated, it is not limited to this.

(式〔A-1〕~式〔A-5〕中，A₁為碳數2~24之烷基或碳數2~24之含氟烷基。)

(In formula [A-1] to formula [A-5], A ₁ is an alkyl group having 2 to 24 carbon atoms or a fluorine-containing alkyl group having 2 to 24 carbon atoms.)

(式〔A-6〕及式〔A-7〕中，A₂表示-O-、-OCH₂-、-CH₂O-、-COOCH₂-、或-CH₂OCO-，A₃表示碳數1~22之烷基、碳數1~22之烷氧基、碳數1~22之含氟烷基或碳數1~22之含氟烷氧基。)

(In formula [A-6] and formula [A-7], A ₂ represents -O-, -OCH ₂ -, -CH ₂ O-, -COOCH ₂ -, or -CH ₂ OCO-, and A ₃ represents carbon Alkyl with 1 to 22 carbons, alkoxy with 1 to 22 carbons, fluorine-containing alkyl with 1 to 22 carbons, or fluorine-containing alkoxy with 1 to 22 carbons.)

(式〔A-8〕~式〔A-10〕中，A₄表示-COO-、-OCO-、-CONH- 、-NHCO-、-COOCH₂-、-CH₂OCO-、-CH₂O-、-OCH₂-、或-CH₂-，A₅為碳數1~22之烷基、烷氧基、含氟烷基或含氟烷氧基。)

(In formula [A-8] to formula [A-10], A ₄ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O -, -OCH ₂ -, or -CH ₂ -, A ₅ is an alkyl group with 1 to 22 carbon atoms, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group.)

(式〔A-11〕及式〔A-12〕中，A₆表示-COO-、-OCO-、-CONH-、-NHCO-、-COOCH₂-、-CH₂OCO-、-CH₂O-、-OCH₂-、-CH₂-、-O-、或-NH-，A₇為氟基、氰基、三氟甲烷基、硝基、偶氮基、甲醯基、乙醯基、乙醯氧基、或羥基。)

(In formula [A-11] and formula [A-12], A ₆ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O -, -OCH ₂ -, -CH ₂ -, -O-, or -NH-, A ₇ is fluoro, cyano, trifluoromethane, nitro, azo, formyl, acetyl, Acetyloxy, or hydroxyl.)

(式〔A-13〕及式〔A-14〕中，A₈為碳數3~12之烷基，1,4-環伸己基之順-反異構係分別為反式異構物。)

(In formula [A-13] and formula [A-14], A ₈ is an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomers of 1,4-cyclohexylene are trans isomers, respectively. )

(式〔A-15〕及式〔A-16〕中，A₉為碳數3~12之烷基，1,4-環伸己基之順-反異構係分別為反式異構物。)

(In formula [A-15] and formula [A-16], A ₉ is an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomers of 1,4-cyclohexylene are trans isomers, respectively. )

As a specific example of the diamine represented by formula (3), the diamine represented by the following formula [A-25] - formula [A-30] is mentioned, but it is not limited to these.

(式〔A-25〕~式〔A-30〕中，A₁₂表示-COO-、-OCO-、-CONH-、-NHCO-、-CH₂-、-O-、-CO-或-NH-，A₁₃表示碳數1~22之烷基或碳數1~22之含氟烷基。)

(In formula [A-25] ~ formula [A-30], A ₁₂ represents -COO-, -OCO-, -CONH-, -NHCO-, -CH ₂ -, -O-, -CO- or -NH -, A ₁₃ represents an alkyl group with 1 to 22 carbon atoms or a fluorine-containing alkyl group with 1 to 22 carbon atoms.)

As a specific example of the diamine represented by formula (4), the diamine represented by the following formula [A-31] - formula [A-32] is mentioned, but it is not limited to these.

Among them, [A-1], [A-2], [A-3], [A-4], [A-5] are also used from the viewpoint of the ability to align liquid crystal vertically and the response speed of liquid crystal. ], [A-25], [A-26], [A-27], [A-28], [A-29], or [A-30] are preferred.

The above-mentioned diamines can be used as one type or in combination of two or more types according to the characteristics such as liquid crystal alignment, pretilt angle, voltage retention characteristics, and accumulated electric charge when forming a liquid crystal alignment film.

Such a diamine having a side chain for vertically aligning the liquid crystal is preferably 5-50 mol % of the diamine component used in the synthesis of the component (A) using polyamic acid, preferably 10- 40 mol%, especially 15~30 mol%. Therefore, when a diamine having a side chain for vertically aligning liquid crystals is used in an amount of 5 to 50 mol % of the diamine component used in the synthesis of the polyamic acid, it is particularly excellent in terms of the fixing ability of the vertical alignment. .

Moreover, in the range which does not impair the effect of this invention, the other diamine other than the diamine which has the side chain which aligns a liquid crystal vertically can also be used together as a diamine component. Specifically, for example, p-phenylene diamine, 2,3,5,6-tetramethyl-p-phenylene diamine, 2,5-dimethyl-p-phenylene Diamine, m-phenylene diamine, 2,4-dimethyl-m-phenylene diamine Amine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5 -Diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl Alkyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diphenyl Aminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-biphenyl, 3,3'-trifluoro Methyl-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl , 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenyl Methane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl Phenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'-sulfonic acid Diphenylamine, 3,3'-sulfonyldiphenylamine, bis(4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl) Silane, dimethyl-bis(3-aminophenyl)silane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 4,4'-diaminodiphenylamine, 3, 3'-diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl(4,4'-diaminodiphenyl)amine, N-methyl(3,3'-diaminodiphenyl)amine, N-methyl(3,4'-diamine diphenyl)amine, N-methyl(2,2'-diaminodiphenyl)amine, N-methyl(2,3'-diaminodiphenyl)amine, 4,4'- Diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2'-diamine benzophenone, 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8- Diaminonaphthalene, 2,5-di Aminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis(4-aminophenyl)ethane, 1,2- Bis(3-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4amine) phenyl)butane, 1,4-bis(3-aminophenyl)butane, bis(3,5-diethyl-4-aminophenyl)methane, 1,4-bis(4- Aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene ( Methylene)] diphenylamine, 4,4'-[1,3-phenylene bis(methylene)] diphenylamine, 3,4'-[1,4-phenylene bis(methylene) ] diphenylamine, 3,4'-[1,3-phenylene bis(methylene)] diphenylamine, 3,3'-[1,4-phenylene bis(methylene)] diphenylamine, 3,3'-[1,3-phenylenebis(methylene)]diphenylamine, 1,4-phenylenebis[(4-aminophenyl)methanone], 1,4-phenylene bis[(3-aminophenyl)methanone], 1,3-phenylene bis[(4-aminophenyl)methanone], 1,3-phenylene bis[(3-aminophenyl) phenyl) ketone], 1,4-phenylene bis(4-aminobenzoate), 1,4-phenylene bis(3-aminobenzoate), 1,3-phenylene bis(3-aminobenzoate) Phenyl bis(4-aminobenzoate), 1,3-phenylene bis(3-aminobenzoate), bis(4-aminophenyl) terephthalate, bis(3-aminobenzoate) -aminophenyl) terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate, N,N'-(1,4-extended) Phenyl)bis(4-aminobenzylamide), N,N'-(1,3-phenylene)bis(4-aminobenzylamide), N,N'-(1,4-phenylene) Phenyl)bis(3-aminobenzylamide), N,N'-(1,3-phenylene)bis(3-aminobenzylamide), N,N'-bis(4-aminobenzylamine) Phenyl) phthalamide, N,N'-bis(3-aminobenzene base) phthalamide, N,N'-bis(4-aminophenyl)isophthalamide, N,N'-bis(3-aminophenyl)isophthalamide, 9,10-bis (4-aminophenyl)anthracene, 4,4'-bis(4-aminophenoxy)diphenylene, 2,2'-bis[4-(4-aminophenoxy)phenyl ] propane, 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2'-bis(4-aminophenyl)hexafluoropropane, 2,2' -Bis(3-aminophenyl)hexafluoropropane, 2,2'-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2'-bis(4-aminophenyl) ) propane, 2,2'-bis(3-aminophenyl)propane, 2,2'-bis(3-amino-4-methylphenyl)propane, trans-1,4-bis(4- Aminophenyl)cyclohexane, 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, bis(4-aminophenoxy)methane, 1,2-bis(4-amine phenylphenoxy)ethane, 1,3-bis(4-aminophenoxy)propane, 1,3-bis(3-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)propane Phenoxy)butane, 1,4-bis(3-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,5-bis(3-amine) phenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,6-bis(3-aminophenoxy)hexane, 1,7-bis(4- Aminophenoxy)heptane, 1,7-bis(3-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3 -aminophenoxy)octane, 1,9-bis(4-aminophenoxy)nonane, 1,9-bis(3-aminophenoxy)nonane, 1,10-bis( 4-Aminophenoxy)decane, 1,10-bis(3-aminophenoxy)decane, 1,11-bis(4-aminophenoxy)undecane, 1,11- Bis(3-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)dodecane, 1,12-bis(3-aminophenoxy)dodecane, etc. Aromatic diamines; alicyclic diamines such as bis(4-aminocyclohexyl)methane, bis(4-amino-3-methylcyclohexyl)methane; 1,3-diaminopropane, 1 ,4-Diamino Butane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diamino Aliphatic diamines such as nonane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, etc.; 1,3-bis[2-( Diamines having urea structures such as p-aminophenyl)ethyl]urea, 1,3-bis[2-(p-aminophenyl)ethyl]-1-tertiary butoxycarbonylurea, etc. ; N-p-aminophenyl-4-p-aminophenyl (tertiary butoxycarbonyl) aminomethylpiperidine and other diamines with nitrogen-containing unsaturated heterocyclic structures; N-tertiary Diamines having N-Boc group such as butoxycarbonyl-N-(2-(4-aminophenyl)ethyl)-N-(4-aminobenzyl)amine; the following (B) The at least one diamine described in the item of the ingredient is selected from the group consisting of formulae (B-1) to (B-5), and diamines exemplified as specific examples thereof; and the like.

Moreover, as another diamine, the photoreaction which has at least one selected from the group consisting of a methacryloyl group, an acryl group, a vinyl group, an allyl group, a coumarin group, a styryl group, and a cinnamyl group can be mentioned. The diamine of the side chain, and the diamine of the side chain which has a site where a radical is generated due to the decomposition of ultraviolet radiation.

Specifically, for example, as the diamine having a photoreactive side chain, the diamine represented by the following general formula (6) is exemplified, but it is not limited thereto.

(式(6)中，R⁶表示單鍵、-CH₂-、-O-、-COO-、-OCO- 、-NHCO-、-CONH-、-NH-、-CH₂O-、-N(CH₃)-、-CON(CH₃)-、或-N(CH₃)CO-，R⁷表示單鍵，或，非取代或被氟原子所取代之碳數1~20之伸烷基，且伸烷基之-CH₂-可任意被-CF₂-或-CH=CH-所取代，在不與以下舉出之任意一個基相鄰時，亦可被此等基所取代；-O-、-COO-、-OCO-、-NHCO-、-CONH-、-NH-、二價之碳環、或二價之雜環。R⁸表示選自下述式之光反應性基。)

(In formula (6), R ⁶ represents a single bond, -CH ₂ -, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, R ⁷ represents a single bond, or, an unsubstituted or fluorine atom-substituted alkylene with 1 to 20 carbon atoms , and -CH ₂ - of alkylene can be arbitrarily substituted by -CF ₂ - or -CH=CH-, when not adjacent to any one of the groups listed below, it can also be substituted by these groups;- O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocycle, or a divalent heterocycle. R ⁸ represents a photoreactive group selected from the following formula. )

The binding positions of the two amine groups (-NH ₂ ) in the formula (6) are not limited. Specifically, with respect to the binding group of the side chain, the positions of 2, 3, 2, 4, 2, 5, 2, 6, 3, 4, 3,5 position. Among them, the position of 2,4, the position of 2,5, or the position of 3,5 is preferable also from the viewpoint of the reactivity at the time of synthesizing the polyamic acid. When considering the ease of synthesizing diamine, the position of 2,4 or the position of 3,5 is more preferable.

As the diamine containing at least one photoreactive group selected from the group consisting of methacryloyl, acryl, vinyl, allyl, coumarin, styryl, and cinnamyl, specifically The following compounds can be exemplified, but are not limited thereto.

(式中，J¹為選自單鍵、-O-、-COO-、-NHCO-、或-NH-之結合基，J²表示單鍵，或非取代或被氟原子所取代之碳數1~20之伸烷基。)

(in the formula, J ¹ is a binding group selected from a single bond, -O-, -COO-, -NHCO-, or -NH-, J ² represents a single bond, or the number of carbons unsubstituted or substituted by fluorine atoms 1~20 alkylene groups.)

The side chain has a site diamine that decomposes by ultraviolet irradiation and generates a radical, and the diamine represented by the following general formula (7) is exemplified, but it is not limited thereto.

(式中，Ar表示選自伸苯基、伸萘基、伸聯苯基之芳香 族烴基，此等亦可經有機基取代，又，氫原子亦可被鹵素原子所取代。R⁹及R¹⁰係各自獨立為碳數1~10之烷基或烷氧基，T₁及T₂係各自獨立為單鍵、-O-、-S-、-COO-、-OCO-、-NHCO-、-CONH-、-NH-、-CH₂O-、-N(CH₃)-、-CON(CH₃)-、或-N(CH₃)CO-，S為單鍵，或非取代或經氟原子所取代之碳數1~20之伸烷基(但伸烷基之-CH₂-或CF₂-可任意被-CH=CH-所取代，在不與以下舉出之任意之基相鄰時，亦可被此等基所取代；-O-、-COO-、-OCO-、-NHCO-、-CONH-、-NH-、二價之碳環、或二價之雜環。)，Q表示下述之構造。)

(In the formula, Ar represents an aromatic hydrocarbon group selected from the group consisting of phenyl-extended, naphthyl-extended and biphenyl-extended, which may also be substituted by organic groups, and hydrogen atoms may also be substituted by halogen atoms. R ⁹ and R ¹⁰ is each independently an alkyl or alkoxy group with 1 to 10 carbon atoms, and T ₁ and T ₂ are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, S is a single bond, or unsubstituted or via The alkylene group with 1 to 20 carbon atoms substituted by fluorine atom (but the -CH ₂ - or CF ₂ - of the alkyl group can be arbitrarily substituted by -CH=CH-, if not in phase with any of the following groups) When adjacent, it can also be substituted by these groups; -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, divalent carbocycle, or divalent heterocycle.) , Q represents the following structure.)

(式中，R表示氫原子或碳原子數1~4之烷基，R¹¹表示-CH₂-、-NR-、-O-、或-S-。)

(In the formula, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ¹¹ represents -CH ₂ -, -NR-, -O-, or -S-.)

The binding positions of the two amine groups (—NH ₂ ) in the above formula (7) are not limited. Specifically, with respect to the binding group of the side chain, the positions of 2, 3, 2, 4, 2, 5, 2, 6, 3, 4, 3,5 position. Among them, the position of 2,4, the position of 2,5, or the position of 3,5 is preferable from the viewpoint of reactivity at the time of synthesizing the polyamic acid. When considering the ease of synthesizing diamine, the position of 2,4 or the position of 3,5 is more preferable.

In particular, in view of ease of synthesis, high versatility, characteristics, etc., the structure represented by the following formula is optimal, but it is not limited thereto.

(式中，n為2~8之整數。)

(In the formula, n is an integer from 2 to 8.)

The above-mentioned other diamines can be used singly or in combination of two or more depending on the characteristics of liquid crystal alignment, pretilt angle, voltage retention characteristics, and accumulated charge when forming a liquid crystal alignment film.

In the synthesis of the polyamic acid, the tetracarboxylic dianhydride to be reacted with the above-mentioned diamine component is not particularly limited. Specifically, pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-Anthracenetetracarboxylic acid, 1,2,5,6-Anthracenetetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3', 4'-biphenyltetracarboxylic acid, bis(3,4-dicarboxyphenyl) ether, 3,3',4,4'-benzophenone tetracarboxylic acid, bis(3,4-dicarboxybenzene) base) bismuth, bis(3,4-dicarboxyphenyl)methane, 2,2-bis(3,4-dicarboxyphenyl)propane, 1,1,1,3,3,3-hexafluoro-2 ,2-bis(3,4-dicarboxyphenyl)propane, bis(3,4-dicarboxyphenyl)dimethylsilane, bis(3,4-dicarboxylate) Phenyl)diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis(3,4-dicarboxyphenyl)pyridine, 3,3',4,4'-diphenyl base tetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid, oxydiphthalic tetracarboxylic acid Acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2 ,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,3 -Dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cycloheptanetetracarboxylic acid, 2,3,4,5-tetrahydrofurantetracarboxylic acid, 3, 4-Dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid, bicyclic [3,3,0]octane-2,4,6,8-tetracarboxylic acid, bicyclo[4,3,0]nonane-2,4,7,9-tetracarboxylic acid, bicyclo[4,4 ,0]decane-2,4,7,9-tetracarboxylic acid, bicyclo[4,4,0]decane-2,4,8,10-tetracarboxylic acid, tricyclo[6.3.0.0<2, 6>] Undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4-(2,5-dioxotetrahydrofuran-3-yl)- 1,2,3,4-Tetrahydronaphthalene-1,2-dicarboxylic acid, Bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic acid, 5-(2 ,5-dioxotetrahydrofuranyl)-3-methyl-3-cyclohexane-1,2-dicarboxylic acid, tetracyclo[6,2,1,1,0,2,7]dodecane-4 ,5,9,10-tetracarboxylic acid, 3,5,6-tricarboxynorbornane-2:3,5:6 dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, etc. Dianhydrides of tetracarboxylic acids. Of course, one type of tetracarboxylic dianhydrides may be used alone or two or more types may be used in combination according to characteristics such as liquid crystal alignment, voltage retention characteristics, and accumulated charge when forming a liquid crystal alignment film.

The method of obtaining polyamic acid by the reaction of raw material diamine (also described as "diamine component") and raw material tetracarboxylic dianhydride (also described as "tetracarboxylic dianhydride component") can be used well-known synthesis method. one Generally, the method of making a diamine component and a tetracarboxylic dianhydride component react in an organic solvent. The reaction of the diamine component and the tetracarboxylic dianhydride component is easily carried out in an organic solvent, and it is advantageous in that no by-product is produced.

The organic solvent used in the above reaction is not particularly limited as long as it can dissolve the produced polyamic acid. In addition, even if it is an organic solvent which does not dissolve the polyamic acid, it can be used by mixing it with the above-mentioned solvent within the range where the produced polyamic acid does not precipitate. In addition, the moisture in the organic solvent can hinder the polymerization reaction and cause the hydrolysis of the produced polyamic acid, so it is preferable to use the organic solvent that has been dehydrated and dried.

As the organic solvent, for example, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, N-methylformamide, N-methylformamide yl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N,N-di Methyl propionamide, N-methyl caprolactam, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfoxide, hexamethyl sulfoxide, γ-butyrolactone, isopropyl alcohol, methyl alcohol Oxymethyl amyl alcohol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cylosol, ethyl ketone Kisalozol, Methyl-Saloxol Acetate, Butyl-Saloxol Acetate, Ethyl-Saloxol Acetate, Butyl-Carbitol, Ethyl-Carbitol, Ethylene Glycol, Ethylene Glycol Alcohol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether , Dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol Propylene Glycol Monoacetate Monomethyl Ether, Dipropylene Glycol Monomethyl Ether, Dipropylene Glycol Monomethyl Ether Propylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate , tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, pentyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, Ethylene carbonate, propyl carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, 3 -Methyl methoxypropionate, methylethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, 3-methylpropionate Propyl oxypropionate, butyl 3-methoxypropionate, diethylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, 2-ethyl-1-hexanol, etc. These organic solvent systems may be used alone or in combination.

For example, when the diamine component and the tetracarboxylic dianhydride component are reacted in an organic solvent, a solution obtained by dispersing or dissolving the diamine component in the organic solvent by stirring, and directly adding the tetracarboxylic dianhydride component, or A method of dispersing or dissolving it in an organic solvent before adding it; conversely, a method of adding a diamine component to a solution obtained by dispersing or dissolving a tetracarboxylic dianhydride component in an organic solvent; alternately adding a tetracarboxylic dianhydride component and The method etc. of a diamine component can use these arbitrary methods. In addition, when the diamine component or the tetracarboxylic dianhydride component is composed of a plurality of compounds, they may be reacted in a state of being mixed in advance, they may be reacted individually in sequence, or they may be reacted individually. The low-molecular-weight body obtained by the reaction is mixed and reacted to become a high-molecular-weight body.

The temperature at which the diamine component and the tetracarboxylic dianhydride component are reacted The temperature can be selected at any temperature, for example, in the range of -20~150℃, preferably in the range of -5~100℃. In addition, the reaction system can be carried out at any concentration. For example, the total amount of the diamine component and the tetracarboxylic dianhydride component is 1 to 50 mass %, preferably 5 to 30 mass %, with respect to the reaction liquid.

In the above-mentioned polymerization reaction, the ratio of the total moles of the tetracarboxylic dianhydride components to the total moles of the diamine components can be arbitrarily selected according to the molecular weight of the polyamic acid to be obtained. In the same manner as in a normal polycondensation reaction, the molecular weight of the polyamic acid produced becomes larger as the molar ratio is closer to 1.0. The preferable range is 0.8~1.2.

The method for synthesizing the polyamic acid used in the present invention is not limited to the above-mentioned method. Similar to the general method for synthesizing polyamic acid, even if the tetracarboxylic acid or tetracarboxylic acid corresponding to the structure is used instead of the above-mentioned tetracarboxylic dianhydride. A tetracarboxylic acid derivative such as a carboxylic acid dihalide can be reacted by a known method to obtain the corresponding polyamic acid.

As a method of imidizing the above-mentioned polyamic acid to obtain polyimide, there are thermal imidization of directly heating a polyamic acid solution, and a catalyst of adding a catalyst to the polyamic acid solution. imidization. Furthermore, the imidization rate from polyimide to polyimide is preferably 30% or more, preferably 50 to 99%, since the voltage holding rate can be improved. On the other hand, from the viewpoint of inhibiting whitening properties, that is, inhibiting polymer precipitation in the varnish, it is preferably 70% or less. If the characteristics of both are considered at the same time, 50~80% is better.

The temperature during thermal imidization of the polyamic acid in the solution is 100 to 400°C, preferably 120 to 250°C, so that the imidization reaction of It is better to remove the generated water to the outside of the system and implement it at the same time.

The catalytic imidization of polyamide can be carried out by adding a basic catalyst and an acid anhydride to the polyamide solution, and stirring at -20 to 250°C, preferably at 0 to 180°C. The amount of the alkaline catalyst is 0.5-30 mol times the amide acid group, preferably 2-20 mol times, and the amount of the acid anhydride is 1-50 mol times the amide acid group, preferably 3- 30 mole times. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, and the like. Among them, pyridine is preferable because it has a moderate alkalinity to enable the reaction. Examples of the acid anhydride include anhydrous acetic acid, anhydrous trimellitic acid, anhydrous pyromellitic acid, and the like. Among them, when anhydrous acetic acid is used, purification after the completion of the reaction becomes easy, so it is preferable. The imidization rate of catalyst imidization can be controlled by adjusting the amount of catalyst, reaction temperature, reaction time and the like.

When recovering the formed polyamic acid or polyimide from the reaction solution of polyamic acid or polyimide, the reaction solution may be put into a poor solvent to precipitate. Examples of the poor solvent used for the formation of the precipitate include methanol, acetone, hexane, butyl cyloxine, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, water, and the like. . The polymer that has been put into the poor solvent and precipitated can be dried under normal pressure or reduced pressure, at normal temperature or under heating, after being recovered by filtration. In addition, if the polymer that has been precipitated and recovered is re-dissolved in the organic solvent, and the operation of re-precipitation and recovery is repeated 2 to 10 times, the impurities in the polymer can be reduced. Examples of the poor solvent at this time include alcohols, ketones, hydrocarbons, and the like. When three or more types of poor solvents selected from these are used, the purification efficiency is further improved, which is preferable.

[Ingredient (B)]

The liquid crystal aligning agent of the present invention contains at least one tetracarboxylic dianhydride component selected from the group consisting of the above formulae (1) and (1') obtained by reacting a tetracarboxylic dianhydride component and a diamine A polyimide precursor and at least one polymer of a group of polyimide obtained by imidizing the polyimide precursor are used as the (B) component.

When a liquid crystal alignment film using at least one tetracarboxylic dianhydride selected from the group of the above-mentioned formulae (1) and (1') as a raw material is used, it is considered that the liquid crystal and the liquid crystal alignment film are formed between the liquid crystal and the liquid crystal alignment film due to light irradiation. The interaction between them can improve the residual DC characteristics.

Examples of the tetracarboxylic dianhydrides selected from the above formulae (1) and (1') include the following compounds, but are not limited to these.

At least one tetracarboxylic dianhydride system selected from the group of the above-mentioned formulas (1-1) to (1-5) is used in the synthesis of polyamic acid, that is, the tetracarboxylic dianhydride component used for the component (B) The amount of 10~100% is better. It is better to use 10~60%. Since the voltage holding ratio can be improved, it is more preferably 10 to 40 mol% of the total tetracarboxylic dianhydride component used in the synthesis of component (B). Herein, at least one tetracarboxylic dianhydride selected from the group consisting of formula (1-1), formula (1-3), and formula (1-5) is used, more preferably 20 to 40 mol%.

Moreover, other tetracarboxylic dianhydrides mentioned in (A) component can also be used as a raw material of (B) component in the range which does not impair the effect of this invention. For example, the tetracarboxylic dianhydride having an aliphatic group or an alicyclic group is used in an amount of 0 to 90 mol % of the tetracarboxylic dianhydride component used in the synthesis of the polyamic acid, that is, the component (B). good.

Moreover, the polymer of (B) component may use as a raw material at least 1 sort(s) of diamine chosen from the group of following formula (B-1)-(B-5).

(式中，Y₁表示二級胺、三級胺，或聚有雜環構造之一價之有機基，Y₂表示二級胺、三級胺，或具有雜環構造之二價之有機基。)

(In the formula, Y ₁ represents a secondary amine, a tertiary amine, or a polyvalent organic group with a heterocyclic structure, and Y ₂ represents a secondary amine, a tertiary amine, or a divalent organic group with a heterocyclic structure .)

By using at least one kind of diamine having a high polarity specific structure selected from the above formulas (B-1) to (B-5), or more separately using a diamine having a carboxyl group and a diamine having a nitrogen-containing aromatic heterocycle One or more of these can improve residual DC characteristics due to salt formation, or hydrogen bonding, which promotes charge transfer through electrostatic interactions.

At least one diamine selected from the group of the above-mentioned formulas (B-1) to (B-5) includes the following diamines, but is not limited thereto.

In addition, the polymer of the component (B) may use the diamine having a side chain for vertically aligning the liquid crystal used in the component (A), or other diamines described in the item of the component (A) above as a raw material .

At least one kind of diamine selected from the group of the above-mentioned formulas (B-1) to (B-5) is used in an amount of 10 to 80 mol % of the diamine component used in the synthesis of the polyamic acid, that is, the component (B). It is better to use 20-70 mol%. Among the diamines exemplified above, it is more preferable to use 3,5-diamines selected from 3,5-diamines in an amount of 20-70 mol % of the total diamine component used in the synthesis of component (B) because it can improve the voltage holding ratio. At least one diamine component of the group consisting of benzoic acid and 3,5-diamino-N-(pyridin-3-ylmethyl)benzylamide is preferable.

In the method for producing the component (B), a tetracarboxylic acid containing at least one tetracarboxylic dianhydride selected from the group of the above formulae (1) and (1'), and other tetracarboxylic dianhydrides as necessary Dianhydride component, combined with diamine component By performing the reaction, a polyimide precursor or polyimide can be obtained.

The method for producing the component (B) is the same as the above-mentioned method for producing the component (A), except that at least one tetracarboxylic dianhydride selected from the group of the above formulae (1) and (1') is used as a raw material. "same.

[Liquid crystal alignment agent]

The liquid crystal aligning agent of the present invention is as described above and has: a polyimide selected from the group consisting of a polyimide precursor having a side chain for vertically aligning liquid crystal, and an imide of the polyimide precursor (A) component, at least one polymer of imine group, and tetracarboxylic dianhydride component selected from at least one tetracarboxylic dianhydride selected from the group consisting of above-mentioned formulas (1) and (1') A polyimide precursor of a reaction product with a diamine, and at least one polymer of a polyimide group of an imide of the polyimide precursor, that is, component (B), and an organic solvent By.

The total content of component (A) and component (B) in the liquid crystal aligning agent of the present invention is not particularly limited, but is preferably 1 to 20 mass %, preferably 3 to 15 mass %, and particularly preferably 3 to 10 mass % %.

In addition, the content ratio of (A) component and (B) component is not particularly limited, for example, in the mass ratio, (A) component: (B) component = X: 10-X (X = 1 to 9), compared with The best is 2:8~8:2. However, (B) component can be the same polymer as (A) component by having the side chain which aligns liquid crystal vertically.

Moreover, the liquid crystal aligning agent of this invention may contain other polymers other than (A) component and (B) component. At this time, in the total composition of the polymer The content of the other polymers is preferably 0.5 to 15 mass %, preferably 1 to 10 mass %.

When considering the strength of the liquid crystal alignment film obtained by coating the liquid crystal alignment agent, the workability during the formation of the coating film, the uniformity of the coating film, etc., the molecular weight of the polymer contained in the liquid crystal alignment agent is determined by GPC (Gel Permeation Chromatography). The weight average molecular weight measured by the ) method is preferably 5,000-1,000,000, more preferably 10,000-150,000.

The organic solvent contained in the liquid crystal aligning agent is not particularly limited as long as it can dissolve or disperse the contained components such as (A) component and (B) component. For example, the organic solvent exemplified in the synthesis of the above-mentioned polyamic acid can be mentioned. From the viewpoint of solubility, among them, N-methyl-2-pyrrolidone, γ-butyrolactone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone are also used. , 3-methoxy-N,N-dimethylpropionamide, etc. are preferred. In particular, N-methyl-2-pyrrolidone or N-ethyl-2-pyrrolidone is preferable, but a mixed solvent of two or more kinds can also be used.

Moreover, it is preferable to use it after mixing the solvent which improves the uniformity or smoothness of a coating film with the organic solvent which has high solubility to the liquid crystal aligning agent containing component.

As a solvent for improving the uniformity and smoothness of the coating film, for example, isopropyl alcohol, methoxymethyl amyl alcohol, methyl silosol, ethyl silosol, butyl silosol, methyl Kisaloxolacetate, Butyl-Saloxolacetate, Ethyl-Saloxolacetate, Butylcarbitol, Ethylcarbitol, Ethylcarbitol acetate, Glycol , ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol Alcohol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, Diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate mono Ethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3 - Methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene , propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate , propylene glycol monoethyl ether acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-Ethoxypropionic acid, 3-methoxypropionic acid, 3-methoxypropionic acid propyl ester, 3-methoxypropionic acid butyl ester, 1-methoxy-2-propanol, 1-ethyl Oxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether -2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2-(2-ethoxypropoxy) propanol, methyl lactate, ethyl lactate, lactic acid n - Propyl ester, n-butyl lactate, isoamyl lactate, 2-ethyl-1-hexanol, etc. Plural types of these solvent systems may be mixed. When using these solvents, 5-80 mass % of the whole solvent contained in a liquid crystal aligning agent is preferable, and 20-60 mass % is more preferable.

Components other than the above may be contained in the liquid crystal aligning agent. Examples thereof include improving the uniformity of the film thickness when applying the liquid crystal aligning agent, or Compounds for surface smoothness, compounds for improving the adhesion between liquid crystal alignment films and substrates, compounds for enhancing the film strength of liquid crystal alignment films, etc.

As a compound which improves the uniformity of a film thickness and surface smoothness, a fluorine-based surfactant, a polysiloxane-based surfactant, a nonionic surfactant, etc. are mentioned, for example. More specifically, for example, Eftop EF301, EF303, EF352 (manufactured by Tohkem Products), Megafac F171, F173, R-30 (manufactured by Dainippon Ink Co., Ltd.), Fluorad FC430, FC431 (manufactured by Sumitomo 3M Co., Ltd.), Asahiguard AG710 , Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.), etc. When these surfactants are used, the usage ratio is preferably 0.01-2 parts by mass, preferably 0.01-1 part by mass, relative to 100 parts by mass of the total amount of polymers contained in the liquid crystal aligning agent.

As a specific example of the compound which improves the adhesiveness of a liquid crystal alignment film and a board|substrate, the compound containing a functional silane, an epoxy group-containing compound, etc. are mentioned, for example. For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane , N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3- Ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-amino Propyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4 ,7-Triazadecane, 10-Triethoxysilyl-1,4,7-triaza Decane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl -3-Aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl- 3-Aminopropyltriethoxysilane, N-bis(oxyethylene)-3-aminopropyltrimethoxysilane, N-bis(oxyethylene)-3-aminopropyltriethoxysilane , Ethylene Glycol Diglycidyl Ether, Polyethylene Glycol Diglycidyl Ether, Propylene Glycol Diglycidyl Ether, Tripropylene Glycol Diglycidyl Ether, Polypropylene Glycol Diglycidyl Ether, Neopentyl Glycol Diglycidyl Ether, 1,6-Hexanediol Diglycidyl Ether, Glycerol Diglycidyl Ether, 2,2-Dibromoneopentyl Glycol Diglycidyl Ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N,N,N',N'-tetraglycidyl-m-diamine, 1,3-bis( N,N-Diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3-( N-allyl-N-epoxypropyl)aminopropyltrimethoxysilane, 3-(N,N-diglycidyl)aminopropyltrimethoxysilane, etc.

In addition, in order to further improve the film strength of the liquid crystal alignment film, 2,2'-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, tetrakis(methoxymethyl)bisphenol, etc. may be added. phenolic compounds. When these compounds are used, it is preferably 0.1 to 30 parts by mass, preferably 1 to 20 parts by mass, relative to 100 parts by mass of the total amount of polymers contained in the liquid crystal aligning agent.

Moreover, as long as the effect of the present invention is not impaired, in addition to the above, a dielectric or conductive substance for the purpose of changing electrical properties such as the permittivity and conductivity of the liquid crystal alignment film may be added to the liquid crystal alignment agent. .

By coating the liquid crystal alignment agent on the substrate and firing, a liquid crystal alignment film for vertically aligning the liquid crystal can be formed.

The liquid crystal aligning agent of the present invention is composed of a polyimide precursor selected from the group consisting of a polyimide precursor having a side chain for vertically aligning the liquid crystal, and a polyimide obtained by imidizing the polyimide precursor. At least one polymer of the group, that is, component (A), and a tetracarboxylic dianhydride component and a The polyimide precursor obtained by the reaction of amine, and the at least one polymer of the polyimide group obtained by imidizing the polyimide precursor, namely the component (B), can The residual DC characteristics are improved.

The substrate is not particularly limited as long as it is a highly transparent substrate, and plastic substrates such as glass substrates, acrylic substrates, and polycarbonate substrates can be used. In addition, from the viewpoint of simplification of the process, it is preferable to use a substrate on which ITO electrodes for driving liquid crystal or the like have been formed. In addition, in a reflective liquid crystal display element, if the substrate is only on one side, an opaque material such as a silicon wafer can still be used, and a light-reflecting material such as aluminum can also be used as the electrode at this time.

The coating method of the liquid crystal aligning agent is not particularly limited, and examples thereof include methods such as screen printing, lithographic printing, flexographic printing, inkjet printing, etc., or dipping method, roll coating method, slit coating method, spin coating coating method, etc.

The firing temperature of the coating film formed by applying the liquid crystal alignment agent is not limited, for example, it can be performed at any temperature of 100 to 350°C, preferably 120 to 300°C, more preferably 150 to 250°C. This firing system can add Hot plate, hot air circulation furnace, infrared furnace, etc.

Moreover, the thickness of the liquid crystal alignment film obtained by baking is not specifically limited, Preferably it is 5-300 nm, More preferably, it is 10-100 nm.

The liquid crystal display element of the present invention includes two substrates arranged to face each other, a liquid crystal layer disposed between the substrates, and a liquid crystal alignment film formed of the liquid crystal aligning agent of the present invention disposed between the substrates and the liquid crystal layer. The liquid crystal display element of the vertical alignment mode of the liquid crystal cell. Specifically, it is a liquid crystal display element with a vertical alignment method of a liquid crystal cell, and the liquid crystal cell is formed by applying the liquid crystal alignment agent of the present invention on two substrates and firing to form a liquid crystal alignment film, so that a liquid crystal alignment film is formed. This liquid crystal alignment film is produced by arranging two substrates facing each other, sandwiching a liquid crystal layer made of liquid crystal between the two substrates and irradiating ultraviolet rays.

Therefore, it is considered that by using the liquid crystal alignment film formed from the liquid crystal alignment agent of the present invention, and irradiating the liquid crystal alignment film and the liquid crystal layer with ultraviolet rays, the liquid crystal interacts with the liquid crystal alignment film of the present invention, and the liquid crystal residue can be formed. DC is a small liquid crystal display element that is not easy to produce branding.

The substrate used in the liquid crystal display element of the present invention is not particularly limited as long as it is a highly transparent substrate, and is usually a substrate on which a transparent electrode for driving liquid crystal is formed. As a specific example, the thing similar to the board|substrate described in the said liquid crystal alignment film is mentioned.

The liquid crystal display element of the present invention can also use conventional substrates provided with electrode patterns or protrusion patterns, but by having a liquid crystal alignment film formed using the liquid crystal alignment agent of the present invention, even if a single-sided substrate is used to form 1- 10μm line/slit electrode pattern, no slit pattern formed on the opposite substrate The substrate with the structure of the type or protrusion pattern can still move, so it can simplify the manufacturing process of the device, and can achieve high transmittance.

In addition, as a high-function device such as a TFT-type device, a device in which a transistor-like device is formed between an electrode for driving liquid crystal and a substrate is used.

In the case of a transmissive liquid crystal display element, the above-mentioned substrate is generally used, but in a reflection type liquid crystal display element, an opaque substrate such as a silicon wafer can also be used as long as the substrate is only on one side. At this time, the electrodes formed on the substrate can also use materials such as aluminum that reflect light.

The liquid crystal alignment film is formed by coating the liquid crystal alignment agent of the present invention on the substrate, followed by firing, and the details are as described above.

As the liquid crystal composition used in the liquid crystal display element of the present invention, a nematic liquid crystal having negative dielectric anisotropy can be used. For example, dicyanobenzene-based liquid crystals, pyridazine-based liquid crystals, Schiff base-based liquid crystals, oxyazo-based liquid crystals, biphenyl-based liquid crystals, phenylcyclohexane-based liquid crystals, terphenyl-based liquid crystals, and the like can be used . In addition, it is preferable to use an alkenyl-based liquid crystal in combination. As such an alkenyl-based liquid crystal, a conventionally known one can be used. For example, although the compound etc. which are represented by the following formula are mentioned, it is not limited to these.

The liquid crystal composition constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited as long as a liquid crystal material in a vertical alignment mode is used. For example, liquid crystal compositions with negative dielectric anisotropy manufactured by Merck, ie, MLC-6608, MLC-6609, and the like can be used. In addition, a liquid crystal composition containing an alkenyl liquid crystal and having a negative dielectric anisotropy, ie, MLC-3022 and MLC-3023 (including a photopolymerizable compound (RM)) manufactured by Merck, can be used.

As a method of sandwiching the liquid crystal layer between two substrates, a known method can be mentioned. For example, prepare a pair of substrates on which a liquid crystal alignment film has been formed, spread spacers such as beads on the liquid crystal alignment film of one substrate, apply an adhesive around the substrate, and make the surface on the side of the liquid crystal alignment film formed. A method of attaching to another substrate toward the inside, injecting liquid crystal under reduced pressure, and sealing.

Also, prepare a pair of substrates on which a liquid crystal alignment film has been formed, spread a spacer such as beads on the liquid crystal alignment film of one substrate, drop liquid crystals, and then stick the surface of the liquid crystal alignment film on the other side toward the inside. One substrate, and the method of sealing can also manufacture liquid crystal cells. The thickness of the spacer at this time The thickness is preferably 1 to 30 μm, more preferably 2 to 10 μm.

The step of fabricating the liquid crystal cell by irradiating the liquid crystal alignment film and the liquid crystal layer with ultraviolet rays can be performed for any period of time as long as the liquid crystal is sealed. The irradiation amount of ultraviolet rays is, for example, 1 to 60 J/cm ² , preferably 40 J/cm ² or less. If the irradiation amount of ultraviolet rays is small, a decrease in reliability due to damage to members constituting the liquid crystal display element can be suppressed.

The wavelength of ultraviolet rays used is preferably 300~500nm, preferably 300~400nm.

In addition, the ultraviolet irradiation to the liquid crystal alignment film and the liquid crystal layer can also be performed in a state where a voltage is applied and the electric field is maintained. Here, the voltage applied between electrodes is, for example, 5 to 30 Vp-p, or preferably 5 to 20 Vp-p.

In the case of the PSA system having a polymerizable compound in the liquid crystal, when a voltage is applied to the liquid crystal alignment film and the liquid crystal layer and ultraviolet rays are simultaneously irradiated, the polymerizable compound reacts to form a polymer, and the direction of the inclination of the liquid crystal molecules is caused by the polymer. Since it is memorized, the response speed of the acquired liquid crystal display element can be increased. Moreover, the residual DC characteristic also becomes favorable by containing (B) component. At this time, when the amount of ultraviolet irradiation is small, the ultraviolet irradiation time can be reduced and the production efficiency can be improved, which is suitable.

In addition, the above-mentioned liquid crystal alignment agent can not only be used as a liquid crystal alignment agent for the production of vertical alignment liquid crystal display elements such as PSA type liquid crystal display or SC-PVA type liquid crystal display, but also can be suitably used in the production of rubbing treatment or photo-alignment. The liquid crystal alignment film formed by the treatment.

[Example]

The following examples are given to illustrate the present invention in more detail, but the present invention is not limited by these examples. The abbreviations of the compounds used below are as follows.

(acid dianhydride)

BODA: Bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic dianhydride.

CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride.

PMDA: pyromellitic dianhydride.

(diamine)

DBA: 3,5-Diaminobenzoic acid

m-PDA: 1,3-phenylenediamine

p-PDA: 1,4-phenylenediamine

3AMPDA: 3,5-Diamino-N-(pyridin-3-ylmethyl)benzylamide

DDM: 4,4'-Diaminodiphenylmethane

(式DA-6中，t表示反式。)

(In formula DA-6, t represents trans.)

<Solvent>

NMP: N-methyl-2-pyrrolidone.

BCS: Butyl Serosu.

<Polyimide molecular weight measurement>

Apparatus: A room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Quanzhou Science Co., Ltd., Column: Column (KD-803, KD-805) manufactured by Shodex Co., Ltd., Column temperature: 50°C, elution Liquid: N,N'-dimethylformamide (as an additive, lithium bromide-hydrate (LiBr·H ₂ O) is 30 mmol/L, phosphoric acid·anhydrous crystal (o-phosphoric acid) is 30 mmol/L, tetrahydrofuran (THF) ) is 10 ml/L), flow rate: 1.0 ml/min, standard sample for calibration line preparation: TSK standard polyethylene oxide manufactured by Tosoh Corporation (molecular weight about 9000,000, 150,000, 100,000, and 30,000), and , Polyethylene glycol (molecular weight about 12,000, 4,000, and 1,000) manufactured by Polymer Laboratories.

<Measurement of imidization rate>

5)，添加氘化二甲亞碸(DMSO-d₆、0.05質量%TMS混合品)1.0ml，施加超音波使其完全溶解。在NMR測量裝置(日本電子資料公司製之JNW-ECA500)中測量此溶液之500MHz之質子NMR。醯亞胺化率係以源自醯亞胺化前後未變化之構造之質子決定當作基準質子，使用此質子之波峰累算值，與源自出現於9.5~10.0ppm附近之醯胺酸之NH基之質子波峰累算值，藉由以下之式所求得者。尚且，下述式中，x為源自醯胺酸之NH基之質子波峰累算值、y為基準質子之波峰累算值、α為基準質子之對聚醯胺酸(醯亞胺化率為0%)時之醯胺酸之NH基之質子1個的個數比例。 Put 20 mg of polyimide powder into an NMR sample tube (standard for NMR sample tube manufactured by Kusano Scientific Co., Ltd.

5) 1.0 ml of deuterated dimethyl sulfite (DMSO-d ₆ , 0.05 mass % TMS mixture) was added, and ultrasonic waves were applied to dissolve it completely. Proton NMR at 500 MHz of this solution was measured in an NMR measuring apparatus (JNW-ECA500 manufactured by Nippon Electronic Materials Co., Ltd.). The imidization rate is determined by taking the proton originating from the unchanged structure before and after imidization as the reference proton, and using the accumulated value of the peak of this proton, and the difference between the proton originating from the imidic acid appearing in the vicinity of 9.5~10.0ppm. The cumulative value of the proton peak of the NH group is obtained by the following formula. Furthermore, in the following formula, x is the cumulative peak value of the proton derived from the NH group of the aramidic acid, y is the cumulative peak value of the reference proton, and α is the reference proton's p-polyamide (imidization rate). The ratio of the number of protons in the NH group of the amino acid when it is 0%).

Imidization rate (%)=(1-α‧x/y)×100

<Synthesis example 1>

BODA (3.30 g, 13.2 mmol), DA-3 (3.35 g, 8.80 mmol), and m-PDA (1.43 g, 13.2 mmol) were dissolved in NMP (29.8 g) and reacted at 60°C for 4 hours . Then, PMDA (1.85 g, 8.47 mmol) and NMP (9.93 g) were added, and it was made to react at room temperature for 4 hours, and the polyamic acid solution X1 was obtained. The number-average molecular weight of this polyamic acid was 13,000, and the weight-average molecular weight was 39,000.

After adding NMP to this polyamic acid solution (25 g) to dilute to 6.5 mass %, anhydrous acetic acid (5.62 g) and pyridine (4.35 g) were added as imidization catalysts, and the reaction was carried out at 80° C. for 4 hours. The reaction solution was put into methanol (300 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain a polyimide powder A. The imidization rate of this polyimide was 73%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.

NMP (18.0 g) was added to the obtained polyimide powder A (2.0 g), and the mixture was stirred and dissolved at 70° C. for 12 hours. BCS (13.3 g) was added to this solution, and a liquid crystal aligning agent A1 was obtained by stirring at room temperature for 2 hours.

<Synthesis example 2>

BODA (3.30 g, 13.2 mmol), DA-3 (3.35 g, 8.80 mmol), and m-PDA (1.43 g, 13.2 mmol) were dissolved in NMP (29.2 g) and reacted at 60°C for 4 hours . Thereafter, CBDA (1.66 g, 8.47 mmol) and NMP (9.74 g) were added, and the mixture was heated at 40°C. It was made to react for 4 hours to obtain a polyamic acid solution.

Except using this polyimide solution (25g), it carried out similarly to Synthesis Example 1, carried out the imidization reaction, and performed the process after reaction, and obtained the polyimide powder B. The imidization rate of this polyimide was 73%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.

Except that the obtained polyimide powder B (2.0 g) was used instead of the polyimide powder A, the same process as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent U1.

Next, BODA (3.75 g, 15 mmol), DA-3 (1.90 g, 4.99 mmol), and m-PDA (2.16 g, 20.0 mmol) were dissolved in NMP (29.7 g) and reacted at 60° C. for 4 hours Then, PMDA (2.10 g, 9.63 mmol) and NMP (9.92 g) were added, and it was made to react at 40 degreeC for 4 hours, and the polyamic acid solution was obtained.

Except using this polyimide solution (25g), it carried out similarly to Synthesis Example 1, carried out the imidization reaction, and performed the process after reaction, and obtained the polyimide powder C. The imidization rate of this polyimide was 73%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.

Except having used the obtained polyimide powder C (2.0g) instead of the polyimide powder A, it carried out the same process as Synthesis Example 1, and obtained the liquid crystal aligning agent L1.

The obtained 5.0g liquid crystal aligning agent U1 was used as the first component, and 5.0 g of the liquid crystal aligning agent L1 was used as the second component and mixed to obtain liquid crystal alignment Agent A2.

<Synthesis example 3>

BODA (22.5 g, 90.0 mmol), DA-4 (62.1 g, 158 mmol), p-PDA (14.6 g, 135 mmol), 3AMPDA (38.16, 157 mmol) were dissolved in NMP (620 g), and the mixture was dissolved at 55° C. After 2 hours of reaction, CBDA (68.4 g, 349 mmol) and NMP (102 g) were added, and the reaction was carried out at 40° C. for 4 hours to obtain a polyamic acid solution.

To this polyamic acid solution (85 g), NMP was added to dilute to 6.5 mass %, then anhydrous acetic acid (18.87 g) and pyridine (5.85 g) were added as imidization catalysts, and the reaction was carried out at 50° C. for 3 hours. This reaction solution was put into methanol (1000 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder D. The imidization rate of this polyimide was 73%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.

Except that the obtained polyimide powder D (2.0 g) was used instead of the polyimide powder A, the same treatment as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent U2.

Next, BODA (123 g, 491 mmol), DBA (127 g, 837 mmol), and DA-1 (60.7 g, 148 mmol) were dissolved in NMP (1246 g) and allowed to react at 55° C. for 2 hours, and then PMDA (43.0 g) was added. , 197 mmol) and NMP (172 g), were allowed to react at room temperature for 4 hours, and then CBDA (50.6 g, 258 mmol) and NMP were added (202 g), it was made to react at room temperature for 4 hours, and the polyamic acid solution was obtained.

After adding NMP to this polyamic acid solution (700g) and diluting it to 8 mass %, anhydrous acetic acid (172g) and pyridine (54g) were added as imidization catalyst, and it was made to react at 80 degreeC for 4 hours. The reaction solution was put into methanol (7000 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder E. The imidization rate of this polyimide was 73%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.

Except that the obtained polyimide powder E (2.0 g) was used instead of the polyimide powder A, the same treatment as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent L2.

The obtained 5.0 g of the liquid crystal aligning agent U2 was used as the first component, and 5.0 g of the liquid crystal aligning agent L2 was used as the second component and mixed to obtain a liquid crystal aligning agent A3.

<Synthesis example 4>

BODA (1.80 g, 7.19 mmol), DA-3 (2.74 g, 7.20 mmol), 3AMPDA (0.87 g, 3.59 mmol), and DA-2 (2.38 g, 7.20 mmol) were dissolved in NMP (29.7 g), It was made to react at 60 degreeC for 4 hours. Then, CBDA (2.10 g, 10.7 mmol) and NMP (9.89 g) were added, and it was made to react at 40 degreeC for 4 hours, and the polyamic acid solution was obtained.

This polyamic acid solution (25 g) was diluted to 6.5 mass by adding NMP After %, anhydrous acetic acid (4.64 g) and pyridine (3.59 g) were added as imidization catalysts, and the reaction was carried out at 80° C. for 4 hours. The reaction solution was put into methanol (300 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder F. The imidization rate of this polyimide was 74%, the number average molecular weight was 12,500, and the weight average molecular weight was 38,000.

Except that the obtained polyimide powder F (2.0 g) was used instead of the polyimide powder A, the same treatment as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent U3.

Next, BODA (3.15 g, 12.6 mmol), DA-3 (2.40 g, 6.31 mmol), DBA (1.28 g, 8.40 mmol) and 3AMPDA (1.25 g, 6.31 mmol) were dissolved in NMP (30.4 g). It was made to react at 60 degreeC for 4 hours. Then, PMDA (1.79 g, 8.19 mmol) and NMP (10.14 g) were added, and it was made to react at room temperature for 4 hours, and the polyamic acid solution was obtained.

After adding NMP to this polyamic acid solution (25 g) to dilute to 6.5 mass %, anhydrous acetic acid (5.26 g) and pyridine (4.08 g) were added as imidization catalysts, and the reaction was carried out at 80° C. for 4 hours. The reaction solution was put into methanol (300 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder G. The imidization rate of this polyimide was 75%, the number-average molecular weight was 13,000, and the weight-average molecular weight was 38,500.

Except that the obtained polyimide powder G (2.0 g) was used instead of the polyimide powder A, the same treatment was carried out as in Synthesis Example 1, and A liquid crystal alignment agent L3 was obtained.

The obtained 5.0 g of the liquid crystal aligning agent U3 was used as the first component, and 5.0 g of the liquid crystal aligning agent L3 was used as the second component and mixed to obtain a liquid crystal aligning agent A4.

<Synthesis example 5>

BODA (3.75 g, 15 mmol), DA-3 (1.90 g, 4.99 mmol), and m-PDA (2.16 g, 20.0 mmol) were dissolved in NMP (29.1 g) and reacted at 60°C for 4 hours. Then, CBDA (1.89 g, 9.64 mmol) and NMP (9.71 g) were added, and it was made to react at 40 degreeC for 4 hours, and the polyamic acid solution was obtained.

Except using this polyimide solution (25g), it carried out similarly to Synthesis Example 1, carried out the imidization reaction, and performed the process after reaction, and obtained the polyimide powder H. The imidization rate of this polyimide was 73%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.

Except having used the obtained polyimide powder H (2.0g) instead of the polyimide powder A, it carried out the same process as the synthesis example 1, and obtained the liquid crystal aligning agent L4.

The liquid crystal aligning agent A5 was obtained by mixing 5.0 g of the liquid crystal aligning agent U1 obtained in Synthesis Example 2 as the first component and 5.0 g of the liquid crystal aligning agent L4 as the second component.

<Synthesis example 6>

BODA (4.12 g, 16.5 mmol), DA-5 (2.87 g, 6.60 mmol), and DBA (2.34 g, 15.4 mmol) were dissolved in NMP (24.8 g) and reacted at 80°C for 5 hours. Then, CBDA (1.01 g, 5.15 mmol) and NMP (8.30 g) were added, and it was made to react at 40 degreeC for 4 hours, and the polyamic acid solution was obtained.

To this polyamic acid solution (38 g), NMP was added to dilute to 6 mass %, then anhydrous acetic acid (8.43 g) and pyridine (3.27 g) were added as imidization catalysts, and the reaction was carried out at 100° C. for 3 hours. This reaction solution was put into methanol (484 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder I. The imidization rate of this polyimide was 73%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.

Except that the obtained polyimide powder I (2.0 g) was used instead of the polyimide powder A, the same process as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent A6.

<Synthesis example 7>

NMP (10.0 g) was added to the polyamic acid solution X1 (10 g) obtained in Synthesis Example 1, and after stirring at room temperature for 1 hour, BCS (13.3 g) was added, and the solution was obtained by stirring at room temperature for 2 hours. Liquid crystal alignment agent A7.

<Synthesis Example 8>

Make BODA (123 g, 491 mmol), DBA (127 g, 837 mmol), DA-1 (60.7 g, 148 mmol) was dissolved in NMP (1246 g) and reacted at 55° C. for 2 hours, then CA-1 (70.6 g, 197 mmol) and NMP (282 g) were added and reacted at room temperature for 4 After 1 hour, CBDA (50.6 g, 258 mmol) and NMP (202 g) were further added, and the mixture was reacted at room temperature for 4 hours to obtain a polyamic acid solution.

After adding NMP to this polyamic acid solution (40 g) and diluting to 8 mass %, anhydrous acetic acid (9.15 g) and pyridine (2.84 g) were added as imidization catalysts, and it was made to react at 80 degreeC for 3 hours. The reaction solution was poured into methanol (473 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder J. The imidization rate of this polyimide was 74%, the number-average molecular weight was 13,500, and the weight-average molecular weight was 40,000.

Except that the obtained polyimide powder J (2.0 g) was used instead of the polyimide powder A, the same treatment as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent L5.

Liquid crystal aligning agent A8 was obtained by mixing 5.0 g of liquid crystal aligning agent U2 obtained in Synthesis Example 3 as the first component and 5.0 g of liquid crystal aligning agent L5 as the second component.

<Synthesis Example 9>

BODA (2.38 g, 9.51 mmol), DBA (1.45 g, 9.53 mmol), DA-1 (2.34 g, 5.70 mmol), DA-3 (1.45 g, 3.81 mmol) were dissolved in NMP (30.4 g), in After allowing to react at 55°C for 3 hours, CA-1 (2.04 g, 5.69 mmol) and NMP were added (8.17g), it was made to react at room temperature for 4 hours, CBDA (0.60g, 3.06 mmol) and NMP (2.38g) were added, it was made to react at room temperature for 4 hours, and the polyamic acid solution was obtained.

To this polyamic acid solution (40 g), NMP was added to dilute to 6.5 mass %, then anhydrous acetic acid (7.46 g) and pyridine (2.31 g) were added as imidization catalysts, and the reaction was carried out at 80° C. for 3 hours. This reaction solution was put into methanol (465 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder L. The imidization rate of this polyimide was 75%, the number-average molecular weight was 13,000, and the weight-average molecular weight was 39,500.

Except that the obtained polyimide powder L (2.0 g) was used instead of the polyimide powder A, the same treatment as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent L6.

Liquid crystal aligning agent A9 was obtained by mixing 5.0 g of liquid crystal aligning agent U2 obtained in Synthesis Example 3 as the first component and 5.0 g of liquid crystal aligning agent L6 as the second component.

<Synthesis Example 10>

BODA (2.25 g, 8.99 mmol), DA-2 (2.97 g, 8.99 mmol), and DA-3 (3.43 g, 9.01 mmol) were dissolved in NMP (34.6 g) and reacted at 60°C for 4 hours . Then, CBDA (1.75 g, 8.92 mmol) and NMP (6.99 g) were added, and it was made to react at 40 degreeC for 4 hours, and the polyamic acid solution was obtained.

This polyamic acid solution (40 g) was diluted with NMP to 6.5 mass After %, anhydrous acetic acid (7.06g) and pyridine (2.19g) were added as imidization catalysts, and it was made to react at 80 degreeC for 4 hours. This reaction solution was put into methanol (463 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder M. The imidization rate of this polyimide was 74%, the number-average molecular weight was 12,500, and the weight-average molecular weight was 38,500.

Except that the obtained polyimide powder M (2.0 g) was used instead of the polyimide powder A, the same treatment as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent U4.

Next, BODA (1.20 g, 4.80 mmol), DBA (1.46 g, 9.59 mmol), 3AMPDA (1.74 g, 7.18 mmol), and DA-3 (2.74 g, 7.20 mmol) were dissolved in NMP (28.58 g), It was made to react at 60 degreeC for 2 hours. Then, PMDA (1.05 g, 4.81 mmol) and NMP (4.19 g) were added, and it was made to react at room temperature for 4 hours, and then CBDA (2.78 g, 14.18 mmol) and NMP (11.1 g) were added, and the reaction was carried out at room temperature. The reaction was carried out for 4 hours to obtain a polyamic acid solution.

After adding NMP to this polyamic acid solution (40 g) to dilute to 6.5 mass %, anhydrous acetic acid (8.90 g) and pyridine (2.76 g) were added as imidization catalysts, and the reaction was carried out at 80° C. for 4 hours. This reaction solution was put into methanol (472 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder N. The imidization rate of this polyimide was 74%, the number-average molecular weight was 13,000, and the weight-average molecular weight was 39,000.

In addition to replacing the polyimide powder A, the obtained polyimide powder was used instead. Except for N (2.0 g), the same treatment as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent L7.

The obtained 3.0 g of the liquid crystal aligning agent U4 was used as the first component, and 7.0 g of the liquid crystal aligning agent L7 was used as the second component and mixed to obtain a liquid crystal aligning agent A10.

<Synthesis Example 11>

BODA (1.20 g, 4.80 mmol), DBA (1.46 g, 9.59 mmol), 3AMPDA (1.74 g, 7.18 mmol), and DA-3 (2.74 g, 7.20 mmol) were dissolved in NMP (28.58 g) at 60 It was made to react at C for 2 hours. Then, CA-2 (1.41 g, 4.79 mmol) and NMP (5.65 g) were added, and the reaction was carried out at room temperature for 4 hours, and then CBDA (2.78 g, 14.18 mmol) and NMP (11.1 g) were added, and the mixture was kept at room temperature. The reaction was carried out at a temperature for 4 hours to obtain a polyamic acid solution.

To this polyamic acid solution (40 g), NMP was added to dilute to 6.5 mass %, then anhydrous acetic acid (8.61 g) and pyridine (2.67 g) were added as imidization catalysts, and the reaction was carried out at 80° C. for 4 hours. The reaction solution was poured into methanol (470 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder O. The imidization rate of this polyimide was 75%, the number average molecular weight was 14,000, and the weight average molecular weight was 39,000.

Except that the obtained polyimide powder O (2.0 g) was used instead of the polyimide powder A, the same process as in Synthesis Example 1 was performed to obtain a liquid crystal aligning agent L8.

Liquid crystal aligning agent A11 was obtained by mixing 3.0 g of liquid crystal aligning agent U4 obtained in Synthesis Example 10 as the first component and 7.0 g of liquid crystal aligning agent L8 as the second component.

<Synthesis Example 12>

CA-3 (2.42 g, 10.8 mmol), DA-6 (2.40 g, 9.01 mmol), DA-5 (1.56 g, 3.59 mmol), and DA-7 (2.67 g, 5.40 mmol) were dissolved in NMP (31.7 In g), it was made to react at 60 degreeC for 4 hours. Then, PMDA (1.30 g, 5.94 mmol) and NMP (5.20 g) were added, and it was made to react at room temperature for 4 hours, and the polyamic acid solution was obtained.

After adding NMP to this polyamic acid solution (40 g) to dilute to 6.0 mass %, anhydrous acetic acid (2.01 g) and pyridine (1.61 g) were added as imidization catalysts, and the reaction was carried out at 110° C. for 4 hours. This reaction solution was put into methanol (480 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder P. The imidization rate of this polyimide was 55%, the number average molecular weight was 11,000, and the weight average molecular weight was 32,000.

Instead of the polyimide powder A, NMP (18.0 g) was added to the obtained polyimide powder P (2.0 g), and the mixture was stirred at 70° C. for 12 hours to dissolve. BCS (13.3 g) was added to this solution, and the liquid crystal aligning agent A12 was obtained by stirring at room temperature for 2 hours.

<Synthesis Example 13>

CA-3 (3.83 g, 17.1 mmol), DA-6 (2.40 g, 9.01 mmol), DA-5 (1.56 g, 3.59 mmol) and DA-7 (2.67 g, 5.40 mmol) were dissolved in NMP (31.7 g) and reacted at 60° C. for 6 hours to obtain a polyamic acid solution.

To this polyamic acid solution (40 g), NMP was added to dilute to 6.0 mass %, and then anhydrous acetic acid (2.07 g) and pyridine (1.60 g) were added as imidization catalysts, and the reaction was carried out at 110° C. for 4 hours. This reaction solution was put into methanol (480 g), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100° C. to obtain a polyimide powder Q. The imidization rate of this polyimide was 55%, the number-average molecular weight was 10,500, and the weight-average molecular weight was 31,500.

NMP (18.0 g) was added to the obtained polyimide powder Q (2.0 g), and the mixture was stirred and dissolved at 70° C. for 12 hours. BCS (13.3 g) was added to this solution, and the liquid crystal aligning agent U5 was obtained by stirring at room temperature for 2 hours.

Next, CA-3 (2.96 g, 13.2 mmol), DDM (3.49 g, 17.6 mmol), and DA-7 (2.18 g, 4.41 mmol) were dissolved in NMP (34.5 g) and reacted at 60°C 4 hours. Then, PMDA (1.54g, 7.04 mmol) and NMP (6.10g) were added, and it was made to react at room temperature for 4 hours, and the polyamic acid solution X2 was obtained. The number-average molecular weight of this polyamic acid was 12,500, and the weight-average molecular weight was 34,000.

NMP (10.0 g) was added to the obtained polyamic acid solution X2 (10 g), and after stirring at room temperature for 1 hour, BCS (13.3 g) was added, and liquid crystal alignment agent L9 was obtained by stirring at room temperature for 2 hours .

The obtained 5.0 g of the liquid crystal aligning agent U5 was used as the first component, and 5.0 g of the liquid crystal aligning agent L9 was used as the second component and mixed to obtain the liquid crystal aligning agent A13.

<Production of liquid crystal cell>

(Example A)

Using the liquid crystal aligning agent A1 obtained in Synthesis Example 1, a liquid crystal cell was produced by the following procedure. The liquid crystal alignment agent A1 obtained in Synthesis Example 1 was spin-coated on the ITO surface of the ITO electrode substrate with a pixel size of 100 μm×300 μm and an ITO electrode pattern with a line/space of 5 μm respectively, and heated at 80°C After the plate was dried for 90 seconds, it was fired in a hot air circulation oven at 200° C. for 20 minutes to form a liquid crystal alignment film with a thickness of 100 nm.

In addition, the liquid crystal aligning agent A1 was spin-coated on the ITO surface on which the electrode pattern was not formed, dried on a hot plate at 80°C for 90 seconds, and then fired in a hot air circulation oven at 200°C for 20 minutes to form a film. 100nm thick liquid crystal alignment film.

Regarding the above-mentioned two substrates, a 4 μm bead spacer was spread on the liquid crystal alignment film of one substrate, and then a sealant (a solvent-based thermosetting epoxy resin) was printed from above. Next, after making the surface on the side where the liquid crystal alignment film of the other substrate is formed face inward, and pasting with the previous substrate, the sealant is hardened to form an empty cell. Liquid crystal MLC-6608 (trade name, manufactured by Merck & Co.), which is a liquid crystal composition containing no alkenyl-based liquid crystal, was injected into this empty cell by a reduced pressure injection method to prepare a liquid crystal cell. Make the acquired liquid crystal cell at 110 Annealing (re-alignment treatment) was performed in a circulating oven at °C for 30 minutes.

Then, the liquid crystal cell was irradiated with light under the following conditions, and the voltage holding ratio and the residual DC were measured under the following conditions. Furthermore, for comparison, under the same conditions, the voltage holding ratio and the residual DC were also measured for the liquid crystal cell not irradiated with light.

[Light irradiation]

From the outside of the liquid crystal cell, irradiate 6J/ ^cm2 of UV through a 365nm bandpass filter (the lamp is USHIO Super High Pressure Mercury Lamp LL, ORC UV Light Measure Model UV-M03A (Accessory: UV-35) is used. measure illuminance).

[Voltage holding ratio]

Using VHR-1A manufactured by Dongyang Technology Co., Ltd., at a temperature of 60°C, a voltage of 1V was applied to the obtained liquid crystal cell for 60μs, and the ratio of the voltage maintained after 1667ms was measured as the voltage retention rate.

[Evaluation of residual DC]

The AC voltage of 5.8Vpp and the DC voltage of 1V were applied to the liquid crystal cell after the voltage holding ratio measurement for 48 hours. Immediately after the DC voltage was removed, the voltage (residual DC) generated in the liquid crystal cell was obtained by the Flicker elimination method. This value is an indicator of afterimage characteristics, and when this value is less than ±30mV, it can be said that afterimage characteristics are excellent.

(Example B, Comparative Example A, Reference Example A)

Except that the liquid crystal alignment agent described in Table 2 was used instead of the liquid crystal alignment agent A1, the same operation as in Example A was performed to manufacture a liquid crystal cell irradiated with light, and the voltage retention and residual DC were measured.

(Example 1)

Except that instead of MLC-6608, a liquid crystal composition containing alkenyl liquid crystal, namely MLC-3022 (trade name of Merck & Co.) was used, the same operation was performed as in Example A to manufacture a light-irradiated liquid crystal cell, and Voltage retention and residual DC were measured.

(Examples 2~4, 8~14)

Except that the liquid crystal aligning agent described in Table 3 was used instead of the liquid crystal aligning agent A1, the same operation as in Example 1 was performed to manufacture a liquid crystal cell irradiated with light, and the voltage retention and residual DC were measured.

(Comparative Examples 1 to 2)

Except that the liquid crystal aligning agent described in Table 3 was used instead of the liquid crystal aligning agent A1, the same operation as in Example 1 was performed to manufacture a liquid crystal cell irradiated with light, and the voltage retention and residual DC were measured.

(Example 5)

In addition to replacing MLC-6608, a liquid crystal composition containing alkenyl liquid crystal and RM (photopolymerizable compound) is used, namely MLC-3023 (Merck & Co. Company's trade name), and the liquid crystal alignment agent A2 was used instead of the liquid crystal alignment agent A1, and the light irradiation was not carried out, but the PSA treatment was carried out under the following conditions. the liquid crystal cell, and measure the voltage holding ratio and residual DC.

[PSA treatment]

Under the state of applying a DC voltage of 15V, from the outside of the liquid crystal cell, irradiate 10J/ ^cm2 of UV through a 325nm high-pass filter (the lamp is USHIO Super High Pressure Mercury Lamp LL, with ORC UV Light Measure Model UV- M03A (Accessory: UV-35) to measure illuminance). Then, UV-irradiation (UV lamp: FLR40SUV32/A-1) was performed for 30 minutes using a UV-FL irradiation device manufactured by Toshiba Lighting Technology Co., Ltd. in a state where no voltage was applied.

(Examples 15 to 19)

Except replacing the liquid crystal aligning agent A2 and using the liquid crystal aligning agent described in Table 4, the same operation as in Example 5 was performed to manufacture a PSA-treated liquid crystal cell, and the voltage retention and residual DC were measured.

(Comparative Examples 3 to 4)

Except replacing the liquid crystal aligning agent A2 and using the liquid crystal aligning agent described in Table 4, the same operation as in Example 5 was performed to manufacture a PSA-treated liquid crystal cell, and the voltage retention and residual DC were measured.

(Example 6)

Except for replacing MLC-6608 with a liquid crystal composition containing alkenyl liquid crystal, namely MLC-3022 (trade name of Merck & Co.), and replacing liquid crystal alignment agent A1 with liquid crystal alignment agent A2, the rest are the same as those in Example A. The same operation was performed to manufacture a light-irradiated liquid crystal cell, and after the liquid crystal cell was annealed in a circulation oven at 150° C. for 3 hours, the voltage retention and residual DC were measured.

(Example 7)

Except for replacing MLC-6608 with a liquid crystal composition containing alkenyl liquid crystal, namely MLC-3022 (trade name of Merck & Co.), and replacing liquid crystal alignment agent A1 with liquid crystal alignment agent A2, the rest are the same as those in Example A. The same operation was performed to manufacture a light-irradiated liquid crystal cell, and the liquid crystal cell was annealed in a circulation oven at 150° C. for 3 hours, and after light irradiation was performed again under the same conditions, the voltage retention and residual DC were measured.

Table 2 shows the results of using MLC-6608, a conventional liquid crystal that does not contain alkenyl liquid crystals as Examples A, B, Comparative Example A, and Reference Example A. In Comparative Example A and Reference Example A that did not use a polymer having a structural unit derived from PMDA, the residual DC was reduced in the past According to the method, that is, in Reference Example A using a highly polar diamine, the accumulation of residual DC was suppressed.

On the other hand, even in Example A and Example B using the polymer having the structural unit derived from PMDA, although there is a difference in the degree of the introduction amount of the structural unit derived from PMDA, compared with Comparative Example A, residual DC was reduced, and a further reduction was found by light irradiation.

Therefore, in MLC-6608, which is a liquid crystal composition that does not contain ethylenic liquid crystals, it is possible to achieve a reduction in the accumulated amount of residual DC by the conventional method, and even in liquid crystals containing polymers having structural units derived from PMDA The alignment film can still reduce the accumulated amount of residual DC by light irradiation.

Table 3 shows the results of using the liquid crystal composition containing the alkenyl liquid crystal, namely MLC-3022. Compared with Table 2, it can be seen that the overall voltage holding ratio decreased. In addition, in Comparative Example 1 and Comparative Example 2, even in Comparative Example 2 using MLC-6608 and using the liquid crystal aligning agent A6 having an effect on residual DC, the accumulated amount of residual DC was large regardless of the presence or absence of light irradiation. On the other hand, in Example 1, Example 2, Example 3, Example 4, Example 8, Example 9, Example 1, Example 2, Example 3, Example 4, Example 8, Example 9, In Example 10, Example 11, Example 12, Example 13, and Example 14, the accumulated amount of residual DC without light irradiation was as large as in Comparative Example 2, but was greatly reduced by light irradiation.

Table 4 shows the results of using the liquid crystal composition comprising alkenyl liquid crystal and RM, namely MLC-3023. As in Table 3, in comparison with Table 2, the The voltage retention rate was low, and the accumulated amount of residual DC was large in Comparative Examples 3 and 4 regardless of whether the PSA treatment was performed or not. However, in Example 5 and Examples 15 to 19 using a polymer having a structural unit derived from PMDA, CA-1 or CA-2, the residual DC was greatly reduced by the PSA treatment.

Therefore, in the case of using a liquid crystal composition containing an alkenyl liquid crystal, there is no effect under the conventional method of reducing residual DC by using a polymer containing a structural unit derived from PMDA, CA-1 or CA-2. The liquid crystal alignment film of the material, and the residual DC can be reduced by applying PSA treatment.

Similar to the examples shown in Tables 3 and 4, the reason why the accumulation of residual DC can be reduced by using a polymer having a structural unit derived from PMDA and performing light irradiation was investigated (Table 5).

In Example 5, after light irradiation was performed using the liquid crystal aligning agent A2 containing a polymer having a structural unit derived from PMDA, the residual DC was reduced compared with the non-irradiation. In addition, after performing annealing treatment at 150° C. for 3 hours after light irradiation, accumulation of residual DC was found to the same extent as the result of no light irradiation (Example 6).

Since there was almost no change in the voltage holding ratio before and after annealing, it was not considered to be the deterioration of the liquid crystal, but was considered to be caused by the elimination of the interaction between the liquid crystal and the liquid crystal alignment film due to light irradiation. Furthermore, after light irradiation was performed again in this state (Example 7), the accumulated amount of residual DC decreased again. This also shows that an interaction occurs between the liquid crystal and the liquid crystal alignment film due to light irradiation, and thereby, the accumulated amount of residual DC can be reduced.

As can be seen from the above, as shown in the examples, even in the case of using a low-reliability liquid crystal composition containing an alkenyl-based liquid crystal, by using a The liquid crystal alignment film from the polymer of the structural unit of the tetracarboxylic dianhydride (for example, PMDA) of the above formula (1) and formula (1') can reduce the accumulation of residual DC after light irradiation or PSA treatment.

[Industrial Availability]

The liquid crystal display element obtained by the present invention can be used as a liquid crystal display element of a vertical alignment method such as a PSA type liquid crystal display or an SC-PVA type liquid crystal display.

Furthermore, the entire contents of the specification, the scope of application, and the abstract of Japanese Patent Application No. 2015-22122 filed on February 6, 2015 are incorporated herein by reference, and incorporated herein as the disclosure of the specification of the present invention.

Claims (5)

A liquid crystal alignment agent, characterized by comprising: the following (A) components, (B) components and an organic solvent; (A) components: selected from polyimide precursors and polyimide precursors At least one polymer of a polyimide group of imines, wherein the aforementioned polyimide precursor is a diamine having a side chain that aligns liquid crystal vertically and accounts for 5-50 mol% of the diamine component and obtained; (B) component: selected from the polyimide precursor of the reaction product of the tetracarboxylic dianhydride component and the diamine component, and the polyimide of the polyimide precursor of the polyimide precursor At least one polymer composed of amines; wherein, the aforementioned tetracarboxylic dianhydride component comprises 10-40 mol% selected from the following formula (1-1), formula (1-3) and formula (1-5) ) grouped by at least one tetracarboxylic dianhydride; however, when component (B) has a side chain that aligns the liquid crystal vertically, it may be the same polymer as component (A);

The liquid crystal aligning agent of claim 1, wherein the content ratio of component (A) and component (B) is calculated by mass ratio as (A) component: (B) component=X: (10-X) (X=1~9 ). The liquid crystal aligning agent according to claim 1, wherein the side chain of component (A) that aligns the liquid crystal vertically is represented by the following formula (a);

l, m and n are integers each independently representing 0 or 1, and R ¹ represents an alkylene group having 2 to 6 carbon atoms, -O-, -COO-, -OCO-, -NHCO-, -CONH-, or carbon Alkylene-ether groups of numbers 1 to 3, R ² , R ³ and R ⁴ each independently represent a phenylene group, a fluorine-containing phenylene group or a cycloalkylene group, R ⁵ represents a hydrogen atom, and the number of carbon atoms is 2 to 24. alkyl, fluorine-containing alkyl with 2 to 24 carbon atoms, monovalent aromatic ring, monovalent aliphatic ring, or monovalent heterocyclic ring. A liquid crystal alignment film having a film thickness of 5 to 300 nm obtained from the liquid crystal alignment agent according to any one of claims 1 to 3. A liquid crystal display element comprising the liquid crystal alignment film of claim 4.