JP5370884B2 - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal display element for obtaining desired ion density, to provide a liquid crystal alignment layer for obtaining the desired ion density in the liquid crystal display element, and to provide a liquid crystal aligning agent for forming the liquid crystal alignment layer. <P>SOLUTION: The liquid crystal alignment layer is formed of the liquid crystal aligning agent containing a polyamic acid which is a reaction product of a predetermined diamine including an oxazole or imidazole skeleton and a tetracarboxylic acid dianhydride, or a derivative thereof, and is used for the liquid crystal display element. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a liquid crystal aligning agent containing a polyamic acid or a derivative thereof obtained by reacting a diamine containing a benzoxazole or benzimidazole skeleton with a tetracarboxylic dianhydride, a liquid crystal aligning film obtained from the liquid crystal aligning agent, and The present invention relates to a liquid crystal display element having the liquid crystal alignment film.

  Liquid crystal display elements are used in various liquid crystal display devices such as monitors for notebook personal computers and desktop personal computers, viewfinders for video cameras, and projection displays. Recently, they are also used for televisions. Furthermore, liquid crystal display elements are also used in optoelectronic-related elements such as optical printer heads, optical Fourier transform elements, and light valves.

  Various elements are known as liquid crystal display elements, but the development of the technology of liquid crystal display elements is not only the improvement of the driving method of the liquid crystal display elements and the structure of the liquid crystal display elements, but also the configuration used for the liquid crystal display elements This is achieved by improving the members. The liquid crystal display element usually has a liquid crystal alignment film for aligning the liquid crystal composition in the liquid crystal layer in a specific direction. The liquid crystal alignment film is one of the important elements related to the display quality of the liquid crystal display element, and the role of the liquid crystal alignment film has become important year by year as the quality of the liquid crystal display element is improved.

  The liquid crystal alignment film is prepared from a liquid crystal aligning agent. The liquid crystal aligning agent mainly used at present is a solution in which polyamic acid or soluble polyimide is dissolved in an organic solvent. The liquid crystal alignment film is formed by applying such a solution to a substrate and then forming the film by means such as heating.

  An important characteristic required for the liquid crystal alignment film in order to improve the display quality of the liquid crystal display element is ion density. When the ion density is high, the voltage applied to the liquid crystal during the frame period is lowered, and as a result, the luminance is lowered, which may hinder normal gradation display.

  As an attempt to solve the above problems, for example, a polyamic acid composition containing a combination of two or more polyamic acids having different physical properties for forming a liquid crystal alignment film is known (see, for example, Patent Documents 1 and 2).

  These prior arts are further studied in terms of the electrical properties of the obtained liquid crystal alignment film and the materials for obtaining desired electrical properties as the liquid crystal alignment agent for forming the present liquid crystal alignment film, which is required to be further improved. There is room for.

  On the other hand, as a polyamic acid, a polyamic acid containing bisbenzimidazole and various aromatic dianhydrides is known (see Non-Patent Document 1). However, the use as a liquid crystal aligning agent has not been studied.

Furthermore, a polyimide resin and a polyimide varnish containing a diamine having a benzoazole structure and an acid anhydride are known (see, for example, Patent Document 3). However, the use as a liquid crystal aligning agent is not examined similarly.
JP 11-193345 A JP-A-11-193347 WO 2008/047591 Pamphlet Journal of Materials Chemistry, 2002, Vol.12, Page 3551-3559

  The present invention provides a liquid crystal display element that achieves the desired ion density, a liquid crystal alignment film that achieves the desired ion density in the liquid crystal display element, and a liquid crystal aligning agent that can form the liquid crystal alignment film. .

  The present inventors use a composition containing a polyamic acid or a derivative thereof made of an aromatic diamine having a benzoxazole or benzimidazole skeleton as a liquid crystal aligning agent, and a liquid crystal display having a liquid crystal alignment film formed thereby The present inventors have found that the device can give a good ion density and completed the present invention.

  The present invention has the following configuration.

[1] In a liquid crystal aligning agent containing polyamic acid or a derivative thereof which is a reaction product of tetracarboxylic dianhydride and diamine,
The diamine is a liquid crystal aligning agent containing a diamine represented by the following general formulas (1) to (8).

（一般式（１）〜（８）中、Ｘは酸素原子又はＮＲ⁶（式中、Ｒ⁶は水素原子、炭素数１〜３０のアルキル基又はフェニル基を示す）を表し、Ｒ¹、Ｒ⁴、Ｒ⁵は、それぞれ独立して、単環又は複数の環から構成される芳香族環基又は複素環基を表し、Ｒ²、Ｒ³はそれぞれ独立して、単環又は複数の環から構成される芳香族環基、複素環基又は脂肪族環基、これらの環基にアルキレンが結合した基又はアルキレン基を表す。）

(In the general formulas (1) to (8), X represents an oxygen atom or NR ⁶ (wherein R ⁶ represents a hydrogen atom, an alkyl group having 1 to 30 carbon atoms or a phenyl group), and R ¹ , R ⁴ and R ⁵ each independently represent an aromatic ring group or a heterocyclic group composed of a single ring or a plurality of rings, and R ² and R ³ each independently represent a single ring or a plurality of rings. The aromatic ring group, the heterocyclic group, or the aliphatic ring group, and the group or alkylene group in which alkylene is bonded to these ring groups are represented.)

[2] The liquid crystal aligning agent according to [1], wherein the diamine is oxazole represented by the following general formulas (O) -1 to (O) -6.

（一般式（Ｏ）−１〜（Ｏ）−６中、ｎは独立して０〜８の整数を表し、ｍは１〜８の整数を表す。）

(In General Formulas (O) -1 to (O) -6, n independently represents an integer of 0 to 8, and m represents an integer of 1 to 8).

[3] The liquid crystal aligning agent according to [1], wherein the diamine is an imidazole represented by the following general formulas (I) -1 to (I) -6.

（一般式（Ｉ）−１〜（Ｉ）−６中、ｎは独立して０〜８の整数を表し、ｍは１〜８の整数を表す。）

(In General Formulas (I) -1 to (I) -6, n independently represents an integer of 0 to 8, and m represents an integer of 1 to 8).

[4] The diamine is an aromatic oxazole represented by the following general formula (O) -2 or an alkyl oxazole represented by the following general formula (O) -3, [2] Liquid crystal aligning agent.

（一般式（Ｏ）−３中、ｍは１〜８の整数を表す。）

(In General Formula (O) -3, m represents an integer of 1 to 8.)

（一般式（Ｉ）−３中、ｍは１〜８の整数を表す。） [5] As described in [3], the diamine is an aromatic imidazole represented by the following general formula (I) -2 or an alkylimidazole represented by the following general formula (I) -3. Liquid crystal aligning agent.

(In General Formula (I) -3, m represents an integer of 1 to 8.)

[6] Any one of [1] to [5], wherein the diamine further includes a diamine having a side chain structure represented by the following general formulas (VIII) and (X) to (XIII): The liquid crystal aligning agent of one term.

In the general formula (VIII), A ³ represents a single bond, —O—, —COO—, —OCO—, —CO—, —CONH— or — (CH ₂ ) _m — (m represents an integer of 1 to 6). R ¹ represents a group having a steroid skeleton, a group represented by the following general formula (IX), and when the positional relationship between two amino groups bonded to the benzene ring is para, the number of carbon atoms 1 to 30 alkyl is further included, and when the positional relationship is meta, it further includes 1 to 30 carbon alkyl or phenyl, and in the alkyl, any —CH ₂ — is independently —CF ₂ —, -CHF-, -O- (but discontinuous), -CH = CH- or -C≡C- may be substituted, and -CH ₃ is replaced by -CH ₂ F, -CHF ₂ or -CF ₃ may optionally be hydrogen of the phenyl are independently, -F, -CH _3, -OCH ₃ , -OCH ₂ F, -OCHF ₂ or -OCF ₃ may be substituted.

In General Formula (IX), A ⁴ and A ⁵ are each independently a single bond, —O— (but discontinuous), —COO—, —OCO—, —CONH—, —CH═CH—, or carbon number. 1 to 12 alkylene, R ² and R ³ each independently represent —F or —CH ³ , and ring S independently represents 1,4-phenylene, 1,4-cyclohexylene, 1,3 -Represents dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene-1,5-diyl, naphthalene-2,7-diyl or anthracene-9,10-diyl , R ⁴ is —H, —F, alkyl having 1 to 30 carbons, fluorine-substituted alkyl having 1 to 30 carbons, 1 carbon
Represents an alkoxy of ˜30, —CN, —OCH ₂ F, —OCHF ₂ or —OCF ₃ , a and b each represents an integer of 0 to 4; c, d and e each represents an integer of 0 to 3; , F and g each independently represent an integer of 0 to 2, and c + d + e ≧ 1.

In general formulas (X) and (XI), R ⁵ independently represents —H or —CH ₃ , R ⁶ represents —H, or alkyl or alkenyl having 1 to 20 carbon atoms, and A ⁶ independently represents Represents a single bond, —C (═O) — or —CH ₂ —, and in formula (XI), R ⁷ and R ⁸ each independently represents alkyl having 1 to 20 carbons or phenyl.

In the general formulas (XII) and (XIII), A ⁷ independently represents —O— or alkylene having 1 to 6 carbon atoms, and in the general formula (XII), R ⁹ represents —H or carbon atoms of 1 to 30. Represents an alkyl, and any —CH ₂ — of the alkyl having 2 to 30 carbon atoms in the alkyl may be replaced by —O— (but discontinuous), —CH═CH— or —C≡C—. , A ⁸ represents a single bond or alkylene having 1 to 3 carbon atoms, ring T represents 1,4-phenylene or 1,4-cyclohexylene, h represents 0 or 1, and in general formula (XIII), R ¹⁰ represents alkyl having 6 to 22 carbon atoms, and R ¹¹ represents alkyl having 1 to 22 carbon atoms.

[7] The diamine having the side chain structure is represented by the following general formulas (VIII-2), (VIII-4) to (VIII-6), (XII-2), (XII-4), and (XII-6). The liquid crystal aligning agent according to [6], which is at least one selected from compounds represented by:

In the general formula, R ²³ , R ^29, and R ³⁰ each represent alkyl having 1 to 30 carbon atoms or alkoxy having 1 to 30 carbon atoms.

[8] Any of [1] to [7], wherein the diamine further includes a diamine having no side chain structure represented by the following general formulas (I) to (VII) and (XV): A liquid crystal aligning agent according to claim 1.

In general formula (I), X represents — (CH ₂ ) _m — (m represents an integer of 1 to 6), and in general formulas (III) and (V) to (VII), Y is independent. Single bond, —O—, —S—, —S—S—, —SO ₂ —, —CO—, —CONH—, —NHCO—, —NH—, —N (CH ₃ ) — (CH ₂ ) _M —N (CH ₃ ) —, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, — (CH ₂ ) _m —, —O— (CH ₂ ) _m —O— or —S — (CH ₂ ) _m —S— (m represents an integer of 1 to 6), in general formula (V), Z represents a single bond or none, and in general formula (XV), R ³³ and R ³⁴ each independently represents alkyl having 1 to 3 carbon atoms or phenyl, and A ³ independently represents methylene, phenylene or alkyl-substituted phenylene. l represents an integer of 1 to 6, m represents an integer of 1 to 10, and in general formulas (II) to (VII), hydrogen bonded to a cyclohexane ring or a benzene ring is independently -F, _{-CH 3, -CF 3, -OH,} -COOH, may be replaced with -SO ₃ H or -PO ₃ H _2, the hydrogen bonded to the benzene ring in the general formula (IV) with benzyl It may be replaced.

[9] The diamine having no side chain structure is represented by the following structural formulas (IV-1), (IV-2), (IV-15) to (IV-17), (V-1) to (V-). 13), at least one selected from compounds represented by (V-33), (V-35) to (V-37), (VII-2), and (XV-1) The liquid crystal aligning agent as described in [8].

[10] The liquid crystal aligning agent according to any one of [1] to [9], wherein the tetracarboxylic dianhydride includes an aromatic tetracarboxylic dianhydride.

[11] The aromatic tetracarboxylic dianhydride is at least one of compounds represented by the following structural formulas (1), (2), (5) to (7) and (14). The liquid crystal aligning agent as described in [10].

[12] The liquid crystal aligning agent according to [11], wherein the aromatic tetracarboxylic dianhydride is a compound represented by the structural formula (1).

[13] Any of [1] to [12], wherein the tetracarboxylic dianhydride includes one or both of an alicyclic tetracarboxylic dianhydride and an aliphatic tetracarboxylic dianhydride. A liquid crystal aligning agent according to claim 1.

[14] The alicyclic tetracarboxylic dianhydride and the aliphatic tetracarboxylic dianhydride are represented by the following structural formulas (19), (23), (25), (35) to (39), (44). And the liquid crystal aligning agent as described in [13] characterized by being at least one of the compounds represented by (49).

[15] The liquid crystal aligning agent according to [14], wherein the alicyclic tetracarboxylic dianhydride and the aliphatic tetracarboxylic dianhydride are compounds represented by the structural formula (19). .

[16] A liquid crystal aligning agent containing the polyamic acid or its derivatives A and B, wherein the polyamic acid or its derivative A contains the diamine having the side chain structure in the diamine, and the polyamic acid or its The liquid crystal aligning agent according to any one of [6] to [15], wherein the diamine represented by the general formulas (1) to (8) is included in one or both of the diamines of the derivatives A and B .

[17] It further contains at least one selected from an alkenyl-substituted nadiimide compound, a compound having a radical polymerizable unsaturated double bond, an oxazine compound, an oxazoline compound, and an epoxy compound [1] to [16] Liquid crystal aligning agent as described in any one of these.

[18] A liquid crystal alignment film formed by heating a coating film of the liquid crystal aligning agent according to any one of [1] to [17].

[19] A pair of substrates, a liquid crystal layer containing liquid crystal molecules and formed between the pair of substrates, an electrode for applying a voltage to the liquid crystal layer, and a liquid crystal alignment for aligning the liquid crystal molecules in a predetermined direction A liquid crystal display element having a film, wherein the liquid crystal alignment film is the liquid crystal alignment film described in [18].

  According to the present invention, a liquid crystal display element having a high ion density and applicable to various driving methods can be provided.

  The liquid crystal aligning agent of this invention contains the polyamic acid which is a reaction product of tetracarboxylic dianhydride and diamine, or its derivative (s). The polyamic acid derivative is a component that dissolves in a solvent when the liquid crystal aligning agent described later contains a solvent. When the liquid crystal aligning agent is used as a liquid crystal aligning film described later, the main component is polyimide. It is a component that can form a liquid crystal alignment film. Examples of such polyamic acid derivatives include soluble polyimides, polyamic acid esters, polyamic acid amides, and the like. More specifically, 1) polyimide in which all amino acids and carboxyls of polyamic acid are subjected to a dehydration ring-closing reaction, 2) Partially dehydrated ring-closing partial polyimide, 3) Polyamic acid ester in which carboxyl of polyamic acid is converted to ester, 4) Part of acid dianhydride contained in tetracarboxylic dianhydride compound is organic dicarboxylic Examples thereof include polyamic acid-polyamide copolymers obtained by reacting with an acid, and 5) polyamideimide obtained by subjecting a part or all of the polyamic acid-polyamide copolymer to a dehydration ring-closing reaction. The polyamic acid or derivative thereof may be a single compound or two or more.

  The diamine includes diamines represented by the following general formulas (1) to (8). The diamine used in the present invention may be a kind of compound or two or more kinds of compounds.

In the general formulas (1) to (8), X represents an oxygen atom or NR ⁶ (wherein R ⁶ represents a hydrogen atom, an alkyl group having 1 to 30 carbon atoms or a phenyl group), and R ¹ , R ⁴ , R ⁵ each independently represents an aromatic ring group or a heterocyclic group composed of a single ring or a plurality of rings, and R ² and R ³ each independently represent a single ring or a plurality of rings. Represents an aromatic ring group, a heterocyclic group, an aliphatic ring group, a group in which alkylene is bonded to these ring groups, or an alkylene group.

上記一般式（Ｏ）−１〜（Ｏ）−６中、ｎは独立して０〜８の整数を表し、ｍは１〜８の整数を表す。 In the general formulas (1) to (8), when X is an oxygen atom, it represents oxazole, and the diamine is an oxazole represented by the following general formulas (O) -1 to (O) -6. Is preferred.

In the general formulas (O) -1 to (O) -6, n independently represents an integer of 0 to 8, and m represents an integer of 1 to 8.

  Among the oxazoles, an aromatic oxazole represented by (O) -2 or an alkyl oxazole represented by (O) -3 is more preferable.

上記一般式（Ｉ）−１〜（Ｉ）−６中、ｎは独立して０〜８の整数を表し、ｍは１〜８の整数を表す。 In the general formulas (1) to (8), when X is NR ⁶ (wherein R ⁶ represents a hydrogen atom, an alkyl group having 1 to 30 carbon atoms or a phenyl group), it represents imidazole, The diamine is preferably an imidazole represented by the following general formulas (I) -1 to (I) -6.

In the general formulas (I) -1 to (I) -6, n independently represents an integer of 0 to 8, and m represents an integer of 1 to 8.

  Among the imidazoles, an aromatic imidazole represented by (I) -2 or an alkylimidazole represented by (I) -3 is more preferable.

  In the present invention, examples of the diamines represented by the general formulas (1) to (8) include the following compounds.

  Among the diamines, those particularly preferably used are represented by (o-9), (o-10), (o-22), (i-5) to (i-10), (i-22). A compound.

  The diamines represented by the general formulas (1) to (8) express the polyamic acid in the liquid crystal aligning agent of the present invention from the viewpoint of expressing a desired ion density in the liquid crystal display element and realizing its long-term stability. It is preferable that 20-100% is contained by molar ratio in the diamine to comprise, and it is more preferable that 35-100% is contained.

The diamine represented by the general formulas (1) to (8) can be produced by a known method. As such a production method, for example, as described in Non-Patent Document 1, 1,2-phenylenediamine is reacted with phthalic anhydride in a nitrogen atmosphere, and the reaction product is dissolved in concentrated sulfuric acid to produce fuming nitric acid. And a method of reducing the nitro group of a compound obtained by mixing with an amino group under normal reducing conditions using a reducing agent such as tin or hydrochloric acid.

  The diamine may contain only the diamine represented by the general formulas (1) to (8) or may further contain other diamines. Examples of the other diamine include a diamine having a side chain structure and a diamine having no side chain structure. Such other diamines may be one kind of compound or two or more kinds of compounds.

  The diamine having the side chain structure has a substituent (side chain) that can branch from the main chain and exhibit a desired pretilt angle when the substituent connecting two amino groups is the main chain. Means diamine. The side chain in the diamine having a side chain structure may be appropriately selected according to the required pretilt angle. For example, the side chain includes a group having 3 or more carbon atoms. Examples of the diamine having a side chain structure include compounds represented by the following general formulas (VIII) and (X) to (XIII).

In the general formula (VIII), A ³ represents a single bond, —O—, —COO—, —OCO—, —CO—, —CONH— or — (CH ₂ ) _m — (m represents an integer of 1 to 6). R ¹ represents a group having a steroid skeleton, a group represented by the following general formula (IX), and when the positional relationship between two amino groups bonded to the benzene ring is para Further includes alkyl having 1 to 30 carbon atoms, and further includes alkyl having 1 to 30 carbon atoms or phenyl when the positional relationship is meta. In the alkyl, any —CH ₂ — may be independently replaced by —CF ₂ —, —CHF—, —O— (but discontinuous), —CH═CH— or —C≡C—. well, -CH ₃ may be replaced with -CH ₂ F, -CHF ₂ or -CF _3. The hydrogen of the phenyl are _{independently, -F, -CH 3, -OCH 3} , -OCH 2 F, may be replaced with -OCHF ₂ or -OCF _3.

In General Formula (IX), A ⁴ and A ⁵ are each independently a single bond, —O— (but discontinuous), —COO—, —OCO—, —CONH—, —CH═CH—, or carbon number. 1 to 12 alkylene, R ² and R ³ each independently represent —F or —CH ₃ , and ring S independently represents 1,4-phenylene, 1,4-cyclohexylene, 1,3 -Represents dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene-1,5-diyl, naphthalene-2,7-diyl or anthracene-9,10-diyl , R ⁴ is —H, —F, alkyl having 1 to 30 carbons, fluorine-substituted alkyl having 1 to 30 carbons, 1 carbon
Represents an alkoxy of ˜30, —CN, —OCH ₂ F, —OCHF ₂ or —OCF ₃ , a and b each represents an integer of 0 to 4; c, d and e each represents an integer of 0 to 3; , F and g each independently represent an integer of 0 to 2, and c + d + e ≧ 1.

In general formulas (X) and (XI), R ⁵ independently represents —H or —CH ₃ , R ⁶ represents —H, or alkyl or alkenyl having 1 to 20 carbon atoms, and A ⁶ independently represents Represents a single bond, —C (═O) — or —CH ₂ —. Moreover, in general formula (XI), R < ⁷ > and R < ⁸ > represents a C1-C20 alkyl or phenyl each independently.

In general formulas (XII) and (XIII), A ⁷ independently represents —O— or alkylene having 1 to 6 carbon atoms. In general formula (XII), R ⁹ represents —H or alkyl having 1 to 30 carbons, and of the alkyls, any —CH ₂ — of the alkyl having 2 to 30 carbons is —O— (however, Continuous), —CH═CH— or —C≡C—, where A ⁸ represents a single bond or alkylene having 1 to 3 carbon atoms, and ring T represents 1,4-phenylene or 1,4- Represents cyclohexylene, h represents 0 or 1; Furthermore, in general formula (XIII), R < ¹⁰ > represents a C6-C22 alkyl and R < ¹¹ > represents a C1-C22 alkyl.

  Examples of the diamine represented by the general formula (VIII) include diamines represented by the following general formulas (VIII-1) to (VIII-37) and structural formulas (VIII-38) to (VIII-43). .

In general formulas (VIII-1) to (VIII-11), R ²³ preferably represents alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, and alkyl having 5 to 25 carbons or 5 carbons. More preferably, it represents ˜25 alkoxy. R ²⁴ preferably represents alkyl having 1 to 30 carbon atoms or alkoxy having 1 to 30 carbon atoms, and more preferably represents alkyl having 3 to 25 carbon atoms or alkoxy having 3 to 25 carbon atoms.

In general formulas (VIII-12) to (VIII-15), R ²⁵ preferably represents an alkyl having 4 to 30 carbon atoms, and more preferably represents an alkyl having 6 to 25 carbon atoms. In general formulas (VIII-16) and (VIII-17), R ²⁶ preferably represents an alkyl having 6 to 30 carbon atoms, and more preferably represents an alkyl having 8 to 25 carbon atoms.

In the general formulas (VIII-18) to (VIII-37), R ²⁷ preferably represents alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, and alkyl or carbons having 3 to 25 carbons. More preferably, it represents 3 to 25 alkoxy. R ²⁸ preferably represents —H, —F, alkyl having 1 to 30 carbon atoms, alkoxy having 1 to 30 carbon atoms, —CN, —OCH ₂ F, —OCHF ₂ or —OCF _3. More preferably, it represents 3 to 25 alkyl or C3 to C25 alkoxy.

  Of these, diamines represented by general formulas (VIII-1) to (VIII-11) are preferred, and diamines represented by general formulas (VIII-2) and (VIII-4) to (VIII-6) are preferred. More preferred.

In the diamine represented by the general formula (X), in the general formula (X), one of the two “NH ₂ —Ph—A ⁶ —O—” is bonded to the 3-position of the steroid skeleton, and the other is 6 It is preferable that it is bonded to the position. The two amino groups are each bonded to a phenyl ring carbon, and preferably bonded to meta or para with respect to the bonding position of A ⁶ .

  Examples of the diamine represented by the general formula (X) include diamines represented by the following structural formulas (X-1) to (X-4).

In the diamine represented by the general formula (XI), in the general formula (XI), two “NH ₂ — (R ⁶ —) Ph—A ⁶ —O—” are each bonded to carbon of the phenyl ring. However, it is preferably bonded to a meta or para carbon relative to the carbon to which the steroid skeleton is bonded. The two amino groups are each bonded to the phenyl ring carbon, but are preferably bonded to meta or para to A ⁶ .

  Examples of the diamine represented by the general formula (XI) include diamines represented by the following structural formulas (XI-1) to (XI-8).

In the diamine represented by the general formula (XII), in the general formula (XII), the two amino groups are each bonded to carbon of the phenyl ring, but are bonded to meta or para to A ⁷ . It is preferable.

  Examples of the diamine represented by the general formula (XII) include diamines represented by the following general formulas (XII-1) to (XII-8).

In general formulas (XII-1) to (XII-3), R ²⁹ preferably represents —H, alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, and alkyl having 3 to 30 carbons or More preferably, it represents an alkoxy having 3 to 30 carbon atoms. In general formulas (XII-4) to (XII-8), R ³⁰ preferably represents —H, alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, and alkyl having 3 to 30 carbons. Or it is more preferable to represent C3-C30 alkoxy.

In the diamine represented by the general formula (XIII), in the general formula (XIII), two amino groups are each bonded to carbon of the phenyl ring, but are bonded to meta or para to A ⁷ . It is preferable.

  Examples of the diamine represented by the general formula (XIII) include diamines represented by the following general formulas (XIII-1) to (XIII-3).

In the general formulas (XIII-1) to (XIII-3), R ³¹ preferably represents an alkyl having 6 to 22 carbon atoms, and more preferably represents an alkyl having 6 to 20 carbon atoms. R ³² preferably represents —H or alkyl having 1 to 22 carbons, and more preferably represents alkyl having 1 to 10 carbons.

  The diamine having the side chain structure is represented by general formulas (VIII-2), (VIII-4) to (VIII-6), (XII-2), (XII-4), and (XII-6). It is preferably at least one selected from compounds.

  The diamine having the side chain structure is preferably contained in a molar ratio of 1 to 90% in the diamine constituting the polyamic acid in the liquid crystal aligning agent of the present invention, from the viewpoint of expressing a desired pretilt angle in the liquid crystal display element. More preferably, it is contained in an amount of 5 to 70%.

  The diamine having no side chain structure is a substituent (side chain) that branches off from the main chain and exhibits a desired pretilt angle when a substituent connecting two amino groups is the main chain. Means a diamine having no Examples of the diamine having no side chain structure include compounds represented by the following general formulas (I) to (VII) and (XV).

In general formula (I), X represents — (CH ₂ ) _m — (m represents an integer of 1 to 6), and in general formulas (III) and (V) to (VII), Y is independent. Single bond, —O—, —S—, —S—S—, —SO ₂ —, —CO—, —CONH—, —NHCO—, —NH—, —N (CH ₃ ) — (CH ₂ ) _M —N (CH ₃ ) —, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, — (CH ₂ ) _m —, —O— (CH ₂ ) _m —O— or —S — (CH ₂ ) _m —S— (m represents an integer of 1 to 6), in general formula (V), Z represents a single bond or none, and in general formula (XV), R ³³ and R ³⁴ each independently represents alkyl having 1 to 3 carbon atoms or phenyl, and A ³ independently represents methylene, phenylene or alkyl-substituted phenylene. l represents an integer of 1 to 6, m represents an integer of 1 to 10, and in general formulas (II) to (VII), hydrogen bonded to a cyclohexane ring or a benzene ring is independently -F, _{-CH 3, -CF 3, -OH,} -COOH, may be replaced with -SO ₃ H or -PO ₃ H _2, the hydrogen bonded to the benzene ring in the general formula (IV) with benzyl It may be replaced.

  Examples of the diamine represented by the general formula (I) include diamines represented by the following structural formulas (I-1) to (I-3).

Examples of the diamine represented by the general formula (II) include the following structural formulas (II-1) and (II
-2).

  Examples of the diamine represented by the general formula (III) include diamines represented by the following structural formulas (III-1) to (III-3).

  Examples of the diamine represented by the general formula (IV) include diamines represented by the following structural formulas (IV-1) to (IV-17).

  Examples of the diamine represented by the general formula (V) include diamines represented by the following structural formulas (V-1) to (V-37).

  Examples of the diamine represented by the general formula (VI) include diamines represented by the following structural formulas (VI-1) to (VI-6).

  Examples of the diamine represented by the general formula (VII) include diamines represented by the following structural formulas (VII-1) to (VII-16).

  Examples of the diamine represented by the general formula (XV) include a compound represented by the following structural formula (XV-1).

Among these, diamines having no side chain structure are structural formulas (IV-1) to (IV).
-5), (IV-15) to (IV-17), (V-1) to (V-13), (V-26), (V-27), (V-31), (V-33) ), (V-35) to (V-37), (VI-1), (VI-2), (VI-6), (VII-1) to (VII-5) and (XV-1) Preferred are diamines represented by the structural formulas (IV-1), (IV-2), (IV-15) to (IV-17), (V-1) to (V-13), (V-33). Diamines represented by (V-35) to (V-37), (VII-2) and (XV-1) are more preferred.

  The diamine having no side chain structure is 1 to 98% in terms of molar ratio in the diamine constituting the polyamic acid in the liquid crystal aligning agent of the present invention from the viewpoint of expressing desired electrical characteristics such as ion density in the liquid crystal display element. It is preferably contained, and more preferably 10 to 95%.

  As the diamine in the present invention, diamines other than the diamines represented by the general formulas (I) to (VIII) and (X) to (XIII) described above can be used. Examples of such other diamines include naphthalene-based diamines having a naphthalene structure, fluorene-based diamines having a fluorene structure, and diamines having a side chain structure other than the general formulas (VIII) to (XII).

  Examples of other diamines include compounds represented by the following general formulas (1 ′) to (8 ′).

In general formulas (1 ′) to (8 ′), R ³⁵ and R ³⁶ each independently represents an alkyl group having 3 to 30 carbon atoms.

  Said other diamine can be used in the range which does not impair the effect of this invention in the diamine which comprises the polyamic acid in the liquid crystal aligning agent of this invention.

In each diamine, the ratio of monoamine to diamine may be 40 mol% or less, and a part of the diamine may be replaced with monoamine. Such replacement can cause termination of the polymerization reaction when the polyamic acid is produced, and further progress of the polymerization reaction can be suppressed. For this reason, the molecular weight of the obtained polymer (polyamic acid or a derivative thereof) can be easily controlled by such replacement, and for example, the coating characteristics of the liquid crystal aligning agent are improved without impairing the effects of the present invention. be able to. As long as the effect of the present invention is not impaired, one or more diamines may be substituted for the monoamine. Examples of the monoamine include aniline, 4-hydroxyaniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n- Undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, and n-eicosylamine Is mentioned.

  The tetracarboxylic dianhydride used in the present invention may be a single compound or two or more compounds. Examples of the tetracarboxylic acid include aromatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, and aliphatic tetracarboxylic dianhydrides.

  The aromatic tetracarboxylic dianhydride is a compound in which at least one of the two acid anhydrides is an acid anhydride with two carboxyls bonded to the aromatic compound. Examples of the aromatic tetracarboxylic dianhydride include compounds represented by the following structural formulas (1) to (18).

  The aromatic tetracarboxylic dianhydride is preferably a compound represented by the structural formulas (1), (2), (5) to (7) and (14), and the structural formula (1) It is more preferable that it is a compound represented by these.

  The alicyclic tetracarboxylic dianhydride is a compound in which at least one of two acid anhydrides is an acid anhydride with two carboxy bonded to the alicyclic compound. Examples of the alicyclic tetracarboxylic dianhydride include compounds represented by the following structural formulas (19) to (22), (24) to (44), and (49) to (65).

  The alicyclic tetracarboxylic dianhydride is a compound represented by the structural formulas (19), (25), (35) to (37), (39), (44) and (49). Is preferable, and the compound represented by the structural formula (19) is more preferable.

  The aliphatic tetracarboxylic dianhydride is a compound having two acid anhydrides based on two carboxyls bonded to an aliphatic compound. Examples of the aliphatic tetracarboxylic dianhydride include compounds represented by the following structural formulas (23), (45) to (48), (66), and (67).

  The aliphatic tetracarboxylic dianhydride is preferably a compound represented by the structural formula (23).

  As the tetracarboxylic dianhydride, other tetracarboxylic dianhydrides other than the tetracarboxylic dianhydrides represented by the structural formulas (1) to (67) can be used. Examples of other tetracarboxylic dianhydrides include tetracarboxylic dianhydrides having a side chain structure. By using tetracarboxylic dianhydride having a side chain structure, the pretilt angle in the liquid crystal display element can be increased.

  Examples of the tetracarboxylic dianhydride having a side chain structure include compounds having a steroid skeleton represented by the following structural formulas (68) and (69).

  The said tetracarboxylic dianhydride can be arbitrarily used about the kind and compounding quantity in the range in which the effect of this invention is achieved.

  A part of the tetracarboxylic dianhydride may be replaced with carboxylic acid monoanhydride. Such replacement can cause termination of the polymerization reaction when the polyamic acid is produced, and further progress of the polymerization reaction can be suppressed. For this reason, the molecular weight of the obtained polymer (polyamic acid or a derivative thereof) can be easily controlled by such replacement, and for example, the coating characteristics of the liquid crystal aligning agent are improved without impairing the effects of the present invention. be able to. The ratio of the carboxylic acid anhydride to the tetracarboxylic dianhydride may be in a range that does not impair the effects of the present invention, but it is preferably set to 10 mol% or less of the total tetracarboxylic dianhydride amount. The tetracarboxylic dianhydride replaced with the carboxylic anhydride may be one kind or two or more kinds as long as the effect of the present invention is not impaired. Examples of the carboxylic acid monoanhydride include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl succinic anhydride, Examples include n-hexadecyl succinic anhydride and cyclohexane anhydride.

  In the tetracarboxylic dianhydride, the ratio of the dicarboxylic acid to the tetracarboxylic dianhydride is in the range of 10 mol% or less, and a part of the tetracarboxylic dianhydride may be replaced with the dicarboxylic acid. The tetracarboxylic dianhydride replaced with the dicarboxylic acid may be one kind or two or more kinds as long as the effect of the present invention is not impaired.

The polyamic acid or derivative thereof may further contain a monoisocyanate compound in the monomer. By including the monoisocyanate compound in the monomer, the terminal of the resulting polyamic acid or derivative thereof is modified, and the molecular weight is adjusted. By using this terminal-modified polyamic acid or derivative thereof, for example, the coating properties of the liquid crystal aligning agent can be improved without impairing the effects of the present invention. It is preferable from said viewpoint that content of the monoisocyanate compound in a monomer is 1-10 mol% with respect to the total amount of the diamine and tetracarboxylic dianhydride in a monomer. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

  The polyamic acid or derivative thereof can be produced in the same manner as a known polyamic acid or derivative thereof used for forming a polyimide film, except that diamines represented by the general formulas (1) to (8) are used. . The total amount of tetracarboxylic dianhydride is preferably approximately equimolar to the total number of moles of diamine (molar ratio of about 0.9 to 1.1).

  The molecular weight of the polyamic acid or derivative thereof is preferably from 10,000 to 500,000, more preferably from 20,000 to 200,000, in terms of polystyrene equivalent weight average molecular weight (Mw). The molecular weight of the polyamic acid or derivative thereof can be determined from measurement by gel permeation chromatography (GPC) method.

  The presence of the polyamic acid or derivative thereof can be confirmed by analyzing the solid content obtained by precipitation with a large amount of poor solvent by IR or NMR. In addition, it is possible to confirm the monomer used by analyzing an extract of the decomposition product of the polyamic acid or its derivative by an aqueous solution of strong alkali such as KOH or NaOH by GC, HPLC or GC-MS. it can.

  The liquid crystal aligning agent of this invention may further contain other components other than the said polyamic acid or its derivative (s). Other components may be one kind or two or more kinds.

  For example, the liquid crystal aligning agent of the present invention may further contain an alkenyl-substituted nadiimide compound from the viewpoint of stabilizing the electrical characteristics of the liquid crystal display element over a long period of time. The alkenyl-substituted nadiimide compound may be a single compound or two or more compounds. From the above viewpoint, the content of the alkenyl-substituted nadiimide compound is preferably 0.01 to 1.00 in terms of a weight ratio with respect to the polyamic acid or its derivative in the liquid crystal aligning agent, and is 0.01 to 0.70. More preferably, it is more preferably 0.01 to 0.50.

  The alkenyl-substituted nadiimide compound is preferably a compound that can be dissolved in a solvent that dissolves the polyamic acid or derivative thereof used in the present invention. Examples of such alkenyl-substituted nadiimide compounds include compounds represented by the following general formula (Ina).

In the general formula (Ina), L ¹ and L ² each independently represent hydrogen, alkyl having 1 to 12 carbons, alkenyl having 3 to 6 carbons, cycloalkyl having 5 to 8 carbons, aryl or benzyl. , N represents 1 or 2.

When n = 1, W is alkyl of 1 to 12 carbon atoms, alkenyl having 2 to 6 carbon atoms, cycloalkyl of 5 to 8 carbon atoms, having 6 to 12 carbon atoms aryl, benzyl, -Z ¹ - (O) _{^{q - (Z 2 O) r}} -Z 3 -H (Z 1, Z 2 and Z ³ represents an alkylene of 2 to 6 carbon atoms independently, q represents 0 or 1, and r is 1 to 30 -(Z ⁴ ) _s -BZ ⁵ -H (wherein Z ⁴ and Z ⁵ are independently alkylene having 1 to 4 carbon atoms or cyclo having 5 to 8 carbon atoms). Represents a alkylene, B represents phenylene, and s represents 0 or 1.) —B—T—B—H (B represents phenylene, and T represents —CH ₂ —, — _{C (CH 3) 2 -,} - O -, - CO -, - S- or SO ₂ -. representing a group represented by), or one to three hydrogen of these groups with a hydroxyl group and Representing a conversion has been based on.

  At this time, preferable W is alkyl having 1 to 8 carbons, alkenyl having 3 to 4 carbons, cyclohexyl, phenyl, benzyl, poly (ethyleneoxy) ethyl having 4 to 10 carbons, phenyloxyphenyl, phenylmethylphenyl, Phenyl isopropylidene phenyl and groups in which one or two hydrogens of these groups are replaced by hydroxyl groups.

Formula when n = 2 in (Ina), W is an alkylene of 2 to 20 carbon atoms, cycloalkylene of 5 to 8 carbon atoms, arylene having 6 to 12 carbon ^{atoms, -Z 1 -O- (Z 2 O} ) a group represented by _r— Z ³ — (the meanings of Z ^{1 to} Z ³ and r are as described above), —Z ⁴ —B—Z ⁵ — (the meanings of Z ⁴ , Z ⁵ and B are are as described above. groups represented by), -B- (O-B) s -T- (B-O) s -B- (B represents a phenylene, T is alkylene of 1 to 3 carbon atoms , -O- or -SO ₂ - represents, s represents a group represented by, or one to three hydrogen is replaced with a hydroxyl group of these groups represent) 0 or 1..

In this case, preferable W is alkylene having 2 to 12 carbon atoms, cyclohexylene, phenylene, tolylene, xylylene, —C ₃ H ₆ —O— (Z ² —O) _r —O—C ₃ H ₆ — (Z ² is It represents an alkylene having 2 to 6 carbon atoms, r groups represented by represented by 1 or 2), -B-T-B- (B represents a phenylene, and T is -CH ₂ -., - O— or —SO ₂ —)), a group represented by —B—O—B—C ₃ H ₆ —B—O—B— (B represents phenylene), and These are groups in which one or two hydrogens of these groups are replaced by hydroxyl groups.

  Such an alkenyl-substituted nadiimide compound, as described in, for example, Japanese Patent No. 2729565, holds an alkenyl-substituted nadic acid anhydride derivative and a diamine at a temperature of 80 to 220 ° C. for 0.5 to 20 hours. A compound obtained by synthesis by the method or a commercially available compound can be used. Specific examples of the alkenyl-substituted nadiimide compound include the following compounds.

  N-methyl-allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-methyl-allylmethylbicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide, N-methyl-methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-methyl-methallylmethylbicyclo [2.2.1] hept- 5-ene-2,3-dicarboximide, N- (2-ethylhexyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide,

N- (2-ethylhexyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-allyl-allylbicyclo [2.2.1] hept-5 -Ene-2,3-dicarboximide, N-allyl-allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-allyl-methallylbicyclo [2.2 .1] Hept-5-ene-2,3-dicarboximide, N-isopropenyl-allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-isopropenyl- Allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-isopropenyl-methallylbicyclo [2.2.1] hept-5-ene-2,3 -Dicarboxyl N-cyclohexyl-allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-cyclohexyl-allyl (methyl) bicyclo [2.2.1] hept-5-ene -2,3-dicarboximide, N-cyclohexyl-methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-phenyl-allylbicyclo [2.2.1] Hept-5-ene-2,3-dicarboximide,

N-phenyl-allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-benzyl-allylbicyclo [2.2.1] hept-5-ene-2 , 3-dicarboximide, N-benzyl-allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N-benzyl-methallylbicyclo [2.2.1] hept -5-ene-2,3-dicarboximide, N- (2-hydroxyethyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (2- Hydroxyethyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (2-hydroxyethyl) -methallylbicyclo [2.2.1] hept -5-ene- , 3-dicarboximide,

N- (2,2-dimethyl-3-hydroxypropyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (2,2-dimethyl-3-hydroxy Propyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (2,3-dihydroxypropyl) -allylbicyclo [2.2.1] hept -5-ene-2,3-dicarboximide, N- (2,3-dihydroxypropyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (3-hydroxy-1-propenyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (4-hydroxycyclohexyl) -allyl (methyl) bicycle [2.2.1] hept-5-ene-2,3-dicarboximide,

N- (4-hydroxyphenyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (4-hydroxyphenyl) -allyl (methyl) bicyclo [2.2 .1] hept-5-ene-2,3-dicarboximide, N- (4-hydroxyphenyl) -methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (4-hydroxyphenyl) -methallylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (3-hydroxyphenyl) -allylbicyclo [2.2. 1] Hept-5-ene-2,3-dicarboximide, N- (3-hydroxyphenyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide , -(P-hydroxybenzyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- {2- (2-hydroxyethoxy) ethyl} -allylbicyclo [2. 2.1] hept-5-ene-2,3-dicarboximide,

N- {2- (2-hydroxyethoxy) ethyl} -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- {2- (2-hydroxyethoxy) ) Ethyl} -methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- {2- (2-hydroxyethoxy) ethyl} -methallylmethylbicyclo [2.2 .1] Hept-5-ene-2,3-dicarboximide, N- [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] -allylbicyclo [2.2.1] hept-5-ene -2,3-dicarboximide, N- [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3
-Dicarboximide, N- [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] -methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- {4- (4-hydroxyphenylisopropylidene) phenyl} -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- {4- (4-hydroxyphenylisopropylidene) Phenyl} -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- {4- (4-hydroxyphenylisopropylidene) phenyl} -methallylbicyclo [2] 2.1] hept-5-ene-2,3-dicarboximide and oligomers thereof,

N, N′-ethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-ethylene-bis (allylmethylbicyclo [2.2. 1] Hept-5-ene-2,3-dicarboximide), N, N′-ethylene-bis (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) N, N′-trimethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-hexamethylene-bis (allylbicyclo [2.2 .1] hept-5-ene-2,3-dicarboximide), N, N′-hexamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxy Imide), N, N′-dodecamethylene Bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N'-dodecamethylene-bis (allylmethylbicyclo [2.2.1] hept-5- Ene-2,3-dicarboximide), N, N′-cyclohexylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′— Cyclohexylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide),

1,2-bis {3 ′-(allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) propoxy} ethane, 1,2-bis {3 ′-(allylmethylbicyclo) [2.2.1] Hept-5-ene-2,3-dicarboximido) propoxy} ethane, 1,2-bis {3 ′-(methallylbicyclo [2.2.1] hept-5-ene -2,3-dicarboximido) propoxy} ethane, bis [2 '-{3'-(allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) propoxy} ethyl] Ether, bis [2 ′-{3 ′-(allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) propoxy} ethyl] ether, 1,4-bis {3 ′ -(Allylbicyclo [2.2.1] he To-5-ene-2,3-dicarboximido) propoxy} butane, 1,4-bis {3 ′-(allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxy Imido) propoxy} butane,

N, N′-p-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-p-phenylene-bis (allylmethylbicyclo [ 2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide), N, N′-m-phenylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N ′-{(1 -Methyl) -2,4-phenylene} -bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N'-p-xylylene-bis (allylbicyclo) [2.2.1] Hept-5-ene-2,3-dica Boxoxyimide), N, N′-p-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-xylylene-bis ( Allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene -2,3-dicarboximide),

2,2-bis [4- {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, 2,2-bis [4- { 4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, 2,2-bis [4- {4- (methallylbicyclo [2] 2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-di Carboximido) phenyl} methane, bis {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} methane,

Bis {4- (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} methane, bis {4- (methallylmethylbicyclo [2.2.1] hept -5-ene-2,3-dicarboximido) phenyl} methane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} ether, bis {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} ether, bis {4- (methallylbicyclo [2.2.1] hept-5 -Ene-2,3-dicarboximido) phenyl} ether, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} sulfone, bis {4 -(Ant Methylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) phenyl} sulfone,

Bis {4- (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} sulfone, 1,6-bis (allylbicyclo [2.2.1] hept- 5-ene-2,3-dicarboximide) -3-hydroxy-hexane, 1,12-bis (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide)- 3,6-dihydroxy-dodecane, 1,3-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) -5-hydroxy-cyclohexane, 1,5-bis { 3 ′-(allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) propoxy} -3-hydroxy-pentane, 1,4-bis (allylbicyclo [2.2.1 ] Hept-5-ene 2,3-dicarboximide) -2-hydroxy - benzene,

1,4-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) -2,5-dihydroxy-benzene, N, N′-p- (2-hydroxy ) Xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-p- (2-hydroxy) xylylene-bis (allylmethylcyclo [2] 2.1] hept-5-ene-2,3-dicarboximide), N, N′-m- (2-hydroxy) xylylene-bis (allylbicyclo [2.2.1] hept-5-ene -2,3-dicarboximide), N, N'-m- (2-hydroxy) xylylene-bis (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) , N, N′-p- (2,3-dihi Proxy) xylylene - bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide),

2,2-bis [4- {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) -2-hydroxy-phenoxy} phenyl] propane, bis {4- (Allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) -2-hydroxy-phenyl} methane, bis {3- (allylbicyclo [2.2.1] hept- 5-ene-2,3-dicarboximide) -4-hydroxy-phenyl} ether, bis {3- (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) -5-hydroxy-phenyl} sulfone, 1,1,1-tri {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide)} phenoxymethylpropane, N , N ' , N ″ -tri (ethylenemethallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) isocyanurate and oligomers thereof.

  Furthermore, the alkenyl-substituted nadiimide compound used in the present invention may be a compound represented by the following structural formula containing an asymmetric alkylene / phenylene group.

Among the alkenyl-substituted nadiimide compounds, preferred compounds are shown below.
N, N′-ethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-ethylene-bis (allylmethylbicyclo [2.2. 1] Hept-5-ene-2,3-dicarboximide), N, N′-ethylene-bis (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) N, N′-trimethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-hexamethylene-bis (allylbicyclo [2.2 .1] hept-5-ene-2,3-dicarboximide), N, N′-hexamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxy Imide), N, N′-dodecamethylene-bis (a) Rilbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-dodecamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2 , 3-dicarboximide), N, N′-cyclohexylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-cyclohexylene- Bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide),

N, N′-p-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-p-phenylene-bis (allylmethylbicyclo [ 2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide), N, N′-m-phenylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N ′-{(1 -Methyl) -2,4-phenylene} -bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N'-p-xylylene-bis (allylbicyclo) [2.2.1] Hept-5-ene-2,3-dicarboxy ), N, N′-p-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-xylylene-bis ( Allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene -2,3-dicarboximide), 2,2-bis [4- {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane 2,2-bis [4- {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, 2,2-bis [4 -{4- (methallylbicyclo [2.2.1 Hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} Methane, bis {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} methane,

Bis {4- (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} methane, bis {4- (methallylmethylbicyclo [2.2.1] hept -5-ene-2,3-dicarboximido) phenyl} methane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} ether, bis {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} ether, bis {4- (methallylbicyclo [2.2.1] hept-5 -Ene-2,3-dicarboximido) phenyl} ether, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} sulfone, bis {4 -(Ant Methylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} sulfone, bis {4- (methallylbicyclo [2.2.1] hept-5-ene-2, 3-Dicarboximido) phenyl} sulfone.

Further preferred alkenyl-substituted nadiimide compounds are shown below.
N, N′-ethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-ethylene-bis (allylmethylbicyclo [2.2. 1] Hept-5-ene-2,3-dicarboximide), N, N′-ethylene-bis (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) N, N′-trimethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-hexamethylene-bis (allylbicyclo [2.2 .1] hept-5-ene-2,3-dicarboximide), N, N′-hexamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxy Imide), N, N′-dodecamethylene-bis (a) Rilbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-dodecamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2 , 3-dicarboximide), N, N′-cyclohexylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-cyclohexylene- Bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide),

N, N′-p-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-p-phenylene-bis (allylmethylbicyclo [ 2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3 -Dicarboximide), N, N′-m-phenylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N ′-{(1 -Methyl) -2,4-phenylene} -bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N'-p-xylylene-bis (allylbicyclo) [2.2.1] Hept-5-ene-2,3-dicarboxy ), N, N′-p-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-xylylene-bis ( Allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide), N, N′-m-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene -2,3-dicarboximide),

2,2-bis [4- {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, 2,2-bis [4- { 4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, 2,2-bis [4- {4- (methallylbicyclo [2] 2.1] hept-5-ene-2,3-dicarboximido) phenoxy} phenyl] propane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-di Carboximido) phenyl} methane, bis {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximido) phenyl} methane, bis {4- (methallylbicyclo [2] 2.1] Hept 5-ene-2,3-dicarboximide) phenyl} methane, bis {4- (methallyl methyl bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) phenyl} methane.

  As a particularly preferred alkenyl-substituted nadiimide compound, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide represented by the following structural formula (Ina-1) ) Phenyl} methane, N, N′-m-xylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) represented by the structural formula (Ina-2), And N, N′-hexamethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboximide) represented by the structural formula (Ina-3).

  For example, the liquid crystal aligning agent of this invention may further contain the compound which has a radically polymerizable unsaturated double bond from a viewpoint of stabilizing the electrical property of a liquid crystal display element for a long term. The compound having a radical polymerizable unsaturated double bond may be a single compound or two or more compounds. The compound having a radically polymerizable unsaturated double bond does not include the alkenyl-substituted nadiimide compound. From the above viewpoint, the content of the compound having a radical polymerizable unsaturated double bond is preferably 0.01 to 1.00 in terms of a weight ratio to the polyamic acid or a derivative thereof, and is preferably 0.01 to 0.00. 70 is more preferable, and 0.01 to 0.50 is even more preferable.

  The ratio of the compound having a radical polymerizable unsaturated double bond to the alkenyl-substituted nadiimide compound is from the viewpoint of reducing the ion density of the liquid crystal display element, suppressing the increase in ion density over time, and further suppressing the afterimage. The weight ratio is preferably 0.1 to 10, and more preferably 0.5 to 5.

Examples of the compound having a radical polymerizable unsaturated double bond include (meth) acrylic acid esters, (meth) acrylic acid derivatives such as (meth) acrylic acid amide, and bismaleimide. The compound having a radically polymerizable unsaturated double bond is more preferably a (meth) acrylic acid derivative having two or more radically polymerizable unsaturated double bonds.

  Specific examples of the (meth) acrylate ester include, for example, cyclohexyl (meth) acrylate, 2-methylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, and dicyclopentanyloxy (meth) acrylate. Ethyl, isobornyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate. Examples include 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate.

Specific examples of the bifunctional (meth) acrylic acid ester include, for example, ethylene bisacrylate, Aronix M-210, Aronix M-240 and Aronix M-6200, which are products of Toa Gosei Chemical Co., Ltd., Nippon Kayaku Co., Ltd. ) Products KAYARAD HDDA, KAYARAD HX-220, KAYARAD R-604 and KAYARAD
R-684, V260, V312 and V335HP which are products of Osaka Organic Chemical Industry Co., Ltd. Is mentioned.

  Specific examples of the trifunctional or higher polyfunctional (meth) acrylic acid ester include, for example, 4,4′-methylenebis (N, N-dihydroxyethylene acrylate aniline), Aronix M-400, Aronix M-405, Aronix M-450. , Aronix M-7100, Aronix M-8030, Aronix M-8060, KAYARAD TMPTA, KAYARAD DPCA-20, KAYARAD DPCA-30, KAYARAD DPCA-60, KAYARAD DPCA-120, and Osaka Organic Chemical Co., Ltd. There is a certain VGPT.

  Specific examples of the (meth) acrylic acid amide derivative include, for example, N-isopropylacrylamide, N-isopropylmethacrylamide, Nn-propylacrylamide, Nn-propylmethacrylamide, N-cyclopropylacrylamide, N-cyclopropyl. Methacrylamide, N-ethoxyethylacrylamide, N-ethoxyethylmethacrylamide, N-tetrahydrofurfurylacrylamide, N-tetrahydrofurfurylmethacrylamide, N-ethylacrylamide, N-ethyl-N-methylacrylamide, N, N-diethyl Acrylamide, N-methyl-Nn-propylacrylamide, N-methyl-N-isopropylacrylamide, N-acryloylpiperidine, N-acryloylpyrrolidine, N, N′-me Renbisacrylamide, N, N′-ethylenebisacrylamide, N, N′-dihydroxyethylenebisacrylamide, N- (4-hydroxyphenyl) methacrylamide, N-phenylmethacrylamide, N-butylmethacrylamide, N- (iso -Butoxymethyl) methacrylamide, N- [2- (N, N-dimethylamino) ethyl] methacrylamide, N, N-dimethylmethacrylamide, N- [3- (dimethylamino) propyl] methacrylamide, N- ( Methoxymethyl) methacrylamide, N- (hydroxymethyl) -2-methacrylamide, N-benzyl-2-methacrylamide, and N, N′-methylenebismethacrylamide.

  Among the above (meth) acrylic acid derivatives, N, N′-methylenebisacrylamide, N, N′-dihydroxyethylene-bisacrylamide, ethylenebisacrylate, and 4,4′-methylenebis (N, N-dihydroxyethyleneacrylate) Aniline) is particularly preferred.

  Examples of the bismaleimide include BMI-70 and BMI-80 manufactured by Kay Kasei Co., Ltd., and BMI-1000, BMI-3000, BMI-4000, BMI-5000 and BMI- manufactured by Daiwa Kasei Kogyo Co., Ltd. 7000.

  For example, the liquid crystal aligning agent of this invention may further contain the oxazine compound from a viewpoint of the long-term stability of the electrical property in a liquid crystal display element. The oxazine compound may be a kind of compound or two or more kinds of compounds. From the above viewpoint, the content of the oxazine compound is preferably 0.1 to 50% by weight, more preferably 1 to 40% by weight, and more preferably 1 to 20% with respect to the polyamic acid or a derivative thereof. More preferably, it is% by weight.

The oxazine compound is soluble in a solvent that dissolves polyamic acid or a derivative thereof, and in addition, an oxazine compound having ring-opening polymerizability is preferable.

  Further, the number of oxazine structures in the oxazine compound is not particularly limited.

  Various structures are known for the structure of oxazine. In the present invention, the structure of oxazine is not particularly limited, and examples of the oxazine structure in the oxazine compound include an oxazine structure having an aromatic group containing a condensed polycyclic aromatic group such as benzoxazine and naphthoxazine.

  Examples of the oxazine compound include compounds represented by the following general formulas (a) to (f). In the following general formula, the bond displayed toward the center of the ring indicates that it is bonded to any carbon that forms the ring and can be bonded to a substituent.

In the general formulas (a) to (c), R ¹ and R ² represent an organic group having 1 to 30 carbon atoms. In the general formulas (a) to (f), R ³ to R ⁶ represent hydrogen or a hydrocarbon group having 1 to 6 carbon atoms. In the general formulas (c), (d), and (f), X represents a single bond, —O—, —S—, —S—S—, —SO ₂ —, —CO—, —CONH—, —NHCO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, — (CH ₂ ) _m —, —O— (CH ₂ ) _m —O—, —S— (CH ₂ ) _m -S- is represented. Here, m is an integer of 1-6. In the general formulas (e) and (f), Y is independently a single bond, —O—, —S—, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) _2. -Or C1-C3 alkylene is represented. The benzene ring of the Y, hydrogen bonded to the naphthalene ring, -F _{independently, -CH 3, -OH, -COOH,} -SO 3 H, may be replaced with -PO ₃ H _2.

  The oxazine compound includes an oligomer or polymer having an oxazine structure in the side chain, and an oligomer or polymer having an oxazine structure in the main chain.

  Examples of the oxazine compound represented by the general formula (a) include the following oxazine compounds.

In the formula, R ¹ is preferably alkyl having 1 to 30 carbons, and more preferably alkyl having 1 to 20 carbons.

  Examples of the oxazine compound represented by the general formula (b) include the following oxazine compounds.

In the formula, R ¹ is preferably alkyl having 1 to 30 carbons, and more preferably alkyl having 1 to 20 carbons.

  Examples of the oxazine compound represented by the general formula (c) include an oxazine compound represented by the following general formula (I).

In the general formula (I), R ¹ and R ² are organic groups having 1 to 30 carbon atoms, R ³ to R ⁶ are hydrogen or a hydrocarbon group having 1 to 6 carbon atoms, X is a single bond, —CH ₂ —. , —C (CH ₃ ) ₂ —, —CO—, —O—, —SO ₂ — or —C (CF ₃ ) ₂ —. Examples of the oxazine compound represented by the general formula (I) include the following oxazine compounds.

In the formula, R ¹ is preferably alkyl having 1 to 30 carbons, and more preferably alkyl having 1 to 20 carbons.

  Examples of the oxazine compound represented by the general formula (d) include the following oxazine compounds.

  Examples of the oxazine compound represented by the general formula (e) include the following oxazine compounds.

  Examples of the oxazine compound represented by the general formula (f) include the following oxazine compounds.

Of these, more preferably, the formula (b-1), the formula (c-1), the formula (c-3), the formula (c-5), the formula (c-7), the formula (c-9), Oxazine compounds represented by formula (d-1) to formula (d-6), formula (e-3), formula (e-4), and formula (f-2) to formula (f-4) can be given. .

  The oxazine compound can be produced by the same method as described in International Publication No. 2004/009708, JP-A-11-12258, and JP-A-2004-352670.

  For example, the oxazine compound represented by the general formula (a) is obtained by reacting a phenol compound, a primary amine, and an aldehyde (see International Publication No. 2004/009708 pamphlet).

  The oxazine compound represented by the general formula (b) is obtained by reacting by adding a primary amine to formaldehyde gradually, and then adding and reacting a compound having a naphthol-based hydroxyl group (International Publication 2004 / 009708 pamphlet).

  The oxazine compound represented by the general formula (c) is a secondary aliphatic compound in which an organic solvent contains 1 mole of a phenol compound, at least 2 moles of aldehyde, and 1 mole of primary amine per 1 phenolic hydroxyl group. It can be obtained by reacting in the presence of an amine, a tertiary aliphatic amine, or a basic nitrogen-containing heterocyclic compound (see International Publication No. 2004/009708 and JP-A-11-12258).

  The oxazine compounds represented by the general formulas (d) to (f) are diamines such as 4,4′-diaminodiphenylmethane, diamines having a plurality of benzene rings and an organic group that binds them, aldehydes such as formalin, and the like. It can be obtained by dehydrating and condensing phenol in n-butanol at a temperature of 90 ° C. or higher (see JP 2004-352670 A).

  For example, the liquid crystal aligning agent of this invention may further contain the oxazoline compound from a viewpoint of the long-term stability of the electrical property in a liquid crystal display element. The oxazoline compound is a compound having an oxazoline structure. The oxazoline compound may be a kind of compound or two or more kinds of compounds. From the above viewpoint, the content of the oxazoline compound is preferably 0.1 to 50% by weight, more preferably 1 to 40% by weight, and more preferably 1 to 20% with respect to the polyamic acid or a derivative thereof. It is preferable that it is weight%. Or it is preferable from said viewpoint that content of the said oxazoline compound is 0.1 to 40 weight% with respect to the said polyamic acid or its derivative, when converting the oxazoline structure in an oxazoline compound into oxazoline. .

The oxazoline compound may have only one oxazoline structure in one compound, or may have two or more kinds. Moreover, the said oxazoline compound should just have one said oxazoline structure in one compound, However, It is preferable to have 2 or more. The hexazoline compound may be a polymer having an oxazoline ring structure in the side chain, or may be a copolymer. The polymer having an oxazoline structure in the side chain may be a homopolymer of a monomer having an oxazoline structure in the side chain, or a copolymer of a monomer having an oxazoline structure in the side chain and a monomer having no oxazoline structure It may be. The copolymer having an oxazoline structure in the side chain may be a copolymer of two or more monomers having an oxazoline structure in the side chain, or two or more monomers having an oxazoline structure in the side chain and an oxazoline structure It may also be a copolymer with a monomer that does not have.

  The oxazoline structure is preferably a structure present in the oxazoline compound so that one or both of oxygen and nitrogen in the oxazoline structure can react with the carbonyl group of the polyamic acid.

  Examples of the oxazoline compound include 2,2′-bis (2-oxazoline), 1,2,4-tris- (2-oxazolinyl-2) -benzene, 4-furan-2-ylmethylene-2-phenyl-4H. -Oxazol-5-one, 1,4-bis (4,5-dihydro-2-oxazolyl) benzene, 1,3-bis (4,5-dihydro-2-oxazolyl) benzene, 2,3-bis (4 -Isopropenyl-2-oxazolin-2-yl) butane, 2,2′-bis-4-benzyl-2-oxazoline, 2,6-bis (isopropyl-2-oxazolin-2-yl) pyridine, 2,2 '-Isopropylidenebis (4-tert-butyl-2-oxazoline), 2,2'-isopropylidenebis (4-phenyl-2-oxazoline), 2,2'-methyle Bis (4-tert-butyl-2-oxazoline), and 2,2'-methylenebis (4-phenyl-2-oxazoline) and the like. In addition to these, polymers and oligomers having oxazolyl such as Epocross (trade name, manufactured by Nippon Shokubai Co., Ltd.) are also included.

  For example, the liquid crystal aligning agent of this invention may further contain the epoxy compound from a viewpoint of the long-term stability of the electrical property in a liquid crystal display element. The epoxy compound may be a kind of compound or two or more kinds of compounds. From the above viewpoint, the content of the epoxy compound is preferably 0.1 to 50% by weight, more preferably 1 to 40% by weight, and more preferably 1 to 20% with respect to the polyamic acid or a derivative thereof. More preferably, it is% by weight.

  Examples of the epoxy compound include various compounds having one or more epoxy rings in the molecule. Examples of the compound having one epoxy ring in the molecule include phenyl glycidyl ether, butyl glycidyl ether, 3,3,3-trifluoromethyl propylene oxide, styrene oxide, hexafluoropropylene oxide, cyclohexene oxide, N-glycidyl phthalimide, (Nonafluoro-N-butyl) epoxide, perfluoroethylglycidyl ether, epichlorohydrin, epibromohydrin, N, N-diglycidylaniline, and 3- [2- (perfluorohexyl) ethoxy] -1,2 -Epoxy propane.

  Examples of the compound having two epoxy rings in the molecule include 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, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexene carboxylate and 3 -(N, N-diglycidyl) aminopropyltrimethoxysilane.

  Examples of the compound having three epoxy rings in the molecule include 2- [4- (2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis [4-([2,3- Epoxypropoxy] phenyl)] ethyl] phenyl] propane (trade name “Techmore VG3101L”, manufactured by Mitsui Chemicals, Inc.).

  Examples of the compound having four epoxy rings in the molecule include 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane, and 3- (N-allyl-N-glycidyl) Aminopropyltrimethoxysilane is mentioned.

In addition to the above, examples of the compound having an epoxy ring in the molecule include oligomers and polymers having an epoxy ring. Examples of the monomer having an epoxy ring include glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, and methyl glycidyl (meth) acrylate.

  Examples of other monomers copolymerized with a monomer having an epoxy ring include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, and iso-butyl. (Meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, styrene, methylstyrene, chloromethyl Examples include styrene, (3-ethyl-3-oxetanyl) methyl (meth) acrylate, N-cyclohexylmaleimide, and N-phenylmaleimide.

  Preferable specific examples of the monomer polymer having an epoxy ring include polyglycidyl methacrylate. Preferred examples of the copolymer of the monomer having an epoxy ring and another monomer include N-phenylmaleimide-glycidyl methacrylate copolymer, N-cyclohexylmaleimide-glycidyl methacrylate copolymer, benzyl methacrylate-glycidyl methacrylate. Copolymer, butyl methacrylate-glycidyl methacrylate copolymer, 2-hydroxyethyl methacrylate-glycidyl methacrylate copolymer, (3-ethyl-3-oxetanyl) methyl methacrylate-glycidyl methacrylate copolymer and styrene-glycidyl methacrylate copolymer Is mentioned.

  Among these examples, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′— Tetraglycidyl-4,4′-diaminodiphenylmethane, trade name “Techmore VG3101L”, 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexenecarboxylate and N-phenylmaleimide-glycidyl methacrylate copolymer are particularly preferred preferable.

  For example, the liquid crystal aligning agent of this invention may further contain various additives. Examples of the various additives include high molecular compounds other than polyamic acid and derivatives thereof, and low molecular compounds, which can be selected and used according to their respective purposes.

  For example, the polymer compound includes a polymer compound that is soluble in an organic solvent. It is preferable to add such a polymer compound to the liquid crystal aligning agent of the present invention from the viewpoint of controlling the electrical characteristics and orientation of the liquid crystal alignment film to be formed. Examples of the polymer compound include polyamide, polyurethane, polyurea, polyester, polyepoxide, polyester polyol, silicone-modified polyurethane, and silicone-modified polyester.

  Examples of the low molecular weight compound include 1) a surfactant in accordance with the purpose when improvement in coatability is desired, 2) an antistatic agent when improvement in antistatic is required, and 3) adhesion to the substrate. Silane coupling agents and titanium-based coupling agents when it is desired to improve properties and rubbing resistance, and 4) imidization catalysts when imidization proceeds at low temperatures.

Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-aminoethyl) -3-aminopropylmethyl. Trimethoxysilane, paraaminophenyltrimethoxysilane, paraaminophenyltriethoxysilane, metaaminophenyltrimethoxysilane, metaaminophenyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycid Xylpropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloro Propyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propylamine, and N , N′-bis [3- (trimethoxysilyl) propyl] ethylenediamine.

Examples of the imidization catalyst include aliphatic amines such as trimethylamine, triethylamine, tripropylamine, and tributylamine; aromatics such as N, N-dimethylaniline, N, N-diethylaniline, methyl-substituted aniline, and hydroxy-substituted aniline. Amines: cyclic amines such as pyridine, methyl substituted pyridine, hydroxy substituted pyridine, quinoline, methyl substituted quinoline, hydroxy substituted quinoline, isoquinoline, methyl substituted isoquinoline, hydroxy substituted isoquinoline, imidazole, methyl substituted imidazole, hydroxy substituted imidazole It is done. The imidization catalyst is N, N-dimethylaniline, o-,
It is preferably one or more selected from m-, p-hydroxyaniline, o-, m-, p-hydroxypyridine, and isoquinoline.

  The addition amount of the silane coupling agent is usually 0 to 10% by weight, preferably 0.1 to 3% by weight, based on the total weight of the polyamic acid or its derivative.

  The amount of the imidation catalyst added is usually 0.01 to 5 equivalents, preferably 0.05 to 3 equivalents, relative to the carbonyl group of the polyamic acid or derivative thereof.

  The addition amount of other additives varies depending on the application, but is usually 0 to 30% by weight, preferably 0.1 to 10% by weight, based on the total weight of the polyamic acid or derivative thereof.

  Further, for example, the liquid crystal aligning agent of the present invention is an acrylic acid polymer, an acrylate polymer, and a tetracarboxylic acid as long as the effects of the present invention are not impaired (preferably in an amount within 20% by weight of the polyamic acid or its derivative). It may further contain other polymer components such as polyamide imide which is a reaction product of acid dianhydride, dicarboxylic acid or its derivative and diamine.

  For example, the liquid crystal aligning agent of this invention may further contain the solvent from a viewpoint of the applicability | paintability of a liquid crystal aligning agent, and the adjustment of the density | concentration of the said polyamic acid or its derivative (s). The solvent can be applied without any particular limitation as long as it has a capability of dissolving the polymer component. The said solvent contains the solvent normally used in the manufacturing process and use surface of polymer components, such as a polyamic acid and a soluble polyimide, and can be suitably selected according to the intended purpose. The solvent may be one kind or a mixed solvent of two or more kinds.

  Examples of the solvent include a parent solvent for the polyamic acid or a derivative thereof and other solvents for the purpose of improving coatability.

  Examples of the aprotic polar organic solvent that is a parent solvent for the polyamic acid or derivative thereof include N-methyl-2-pyrrolidone, dimethylimidazolidinone, N-methylcaprolactam, N-methylpropionamide, N, N-dimethyl. Examples include lactones such as acetamide, dimethyl sulfoxide, N, N-dimethylformamide, N, N-diethylformamide, diethylacetamide, and γ-butyrolactone.

  Examples of other solvents for the purpose of improving coating properties include alkyl lactate, 3-methyl-3-methoxybutanol, tetralin, isophorone, ethylene glycol monoalkyl ethers such as ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, etc. Diethylene glycol monoalkyl ether, ethylene glycol monoalkyl or phenyl acetate, triethylene glycol monoalkyl ether, propylene glycol monoalkyl ether such as propylene glycol monomethyl ether, propylene glycol monobutyl ether, dialkyl malonate such as diethyl malonate, dipropylene glycol Dipropylene glycol monoalkyl ethers such as monomethyl ether, and esters such as these acetates Compounds.

  Among these, the solvent is N-methyl-2-pyrrolidone, dimethylimidazolidinone, γ-butyrolactone, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether, and dipropylene glycol. Monomethyl ether is particularly preferred.

  In the present invention, the concentration of the polymer component containing the polyamic acid or derivative thereof in the liquid crystal aligning agent is not particularly limited, but is preferably 0.1 to 40% by weight. When the liquid crystal aligning agent is applied to the substrate, it may be necessary to dilute the polymer component contained in advance with a solvent in order to adjust the film thickness. At this time, from the viewpoint of adjusting the viscosity of the liquid crystal aligning agent to a viscosity suitable for easily mixing the solvent with the liquid crystal aligning agent, the concentration of the polymer component is preferably 40% by weight or less.

  The concentration of the polymer component in the liquid crystal aligning agent may be adjusted depending on the method of applying the liquid crystal aligning agent. When the application method of the liquid crystal aligning agent is a spinner method or a printing method, the concentration of the polymer component is usually 10% by weight or less in order to maintain a good film thickness. Other coating methods such as dipping and ink jet methods may further reduce the concentration. On the other hand, when the concentration of the polymer component is 0.1% by weight or more, the thickness of the obtained liquid crystal alignment film tends to be optimal. Therefore, the concentration of the polymer component is 0.1% by weight or more, preferably 0.5 to 10% by weight in the usual spinner method or printing method. However, depending on the application method of the liquid crystal aligning agent, it may be used at a lower concentration.

  In addition, when using for preparation of a liquid crystal aligning film, the viscosity of the liquid crystal aligning agent of this invention can be determined according to the means and method of forming this liquid crystal aligning agent film. For example, when a film of a liquid crystal aligning agent is formed using a printing machine, it is preferably 5 mPa · s or more from the viewpoint of obtaining a sufficient film thickness, and 100 mPa · s or less from the viewpoint of suppressing printing unevenness. It is preferably 10 to 80 mPa · s. When a liquid crystal aligning agent is applied by spin coating to form a liquid crystal aligning agent film, it is preferably 5 to 200 mPa · s, more preferably 10 to 100 mPa · s from the same viewpoint. The viscosity of the liquid crystal aligning agent can be reduced by curing with dilution or stirring with a solvent.

  The liquid crystal aligning agent of the present invention may be in a form containing one kind of polyamic acid or a derivative thereof, or may be in the form of a so-called polymer blend in which two or more kinds of polyamic acid or a derivative thereof are mixed. Good. The liquid crystal aligning agent in the form of a polymer blend is a liquid crystal aligning agent containing a polyamic acid or its derivatives A and B, and the polyamic acid or its derivative A contains a diamine having the side chain structure in a diamine, and Examples of the liquid crystal aligning agent include a diamine represented by the general formulas (1) to (8) in one or both of the diamines of the polyamic acid or its derivatives A and B.

The polyamic acid or derivative A thereof is a polyamic acid or derivative thereof containing a diamine having the side chain structure. The polyamic acid or derivative B thereof is a polyamic acid or derivative thereof containing a diamine excluding a diamine having a side chain structure. The diamine represented by the general formulas (1) to (8) may be contained in at least one kind of polyamic acid or a derivative thereof mixed in the polymer blend, and both the polyamic acid or the derivatives A and B thereof. It may be contained in all the polyamic acids or derivatives thereof mixed in the polymer blend.

  The liquid crystal alignment film of the present invention is a film formed by heating the coating film of the liquid crystal aligning agent of the present invention described above. The liquid crystal alignment film of the present invention can be obtained by an ordinary method for producing a liquid crystal alignment film from a liquid crystal aligning agent. For example, the liquid crystal alignment film of the present invention includes a step of forming a coating film of the liquid crystal aligning agent of the present invention. The step of heating and baking this can be obtained. About the liquid crystal aligning film of this invention, you may rub the film | membrane obtained at the said baking process as needed.

  The said coating film can be formed by apply | coating the liquid crystal aligning agent of this invention to the board | substrate in a liquid crystal display element similarly to preparation of a normal liquid crystal aligning film. Examples of the substrate include a glass substrate on which an electrode such as an ITO (Indium Tin Oxide) electrode, a color filter, or the like may be provided.

  As a method for applying a liquid crystal aligning agent to a substrate, a spinner method, a printing method, a dipping method, a dropping method, an ink jet method and the like are generally known. These methods are similarly applicable in the present invention.

  The coating film can be baked under conditions necessary for the polyamic acid or its derivative to exhibit a dehydration / ring-closing reaction. For the baking of the coating film, a method of heat treatment in an oven or an infrared furnace, a method of heat treatment on a hot plate, and the like are generally known. These methods are equally applicable in the present invention. In general, it is preferably performed at a temperature of about 150 to 300 ° C. for 1 minute to 3 hours.

  The rubbing treatment can be performed in the same manner as the rubbing treatment for the alignment treatment of a normal liquid crystal alignment film, and may be any conditions as long as sufficient retardation is obtained in the liquid crystal alignment film of the present invention. Particularly preferable conditions are a push-in amount of 0.2 to 0.8 mm, a stage moving speed of 5 to 250 mm / sec, and a roller rotation speed of 500 to 2,000 rpm. As an alignment treatment method for the liquid crystal alignment film, in addition to the rubbing method, an optical alignment method, a transfer method, and the like are generally known. As long as the effects of the present invention can be obtained, these other alignment treatment methods may be used in combination in the rubbing treatment.

  The liquid crystal alignment film of the present invention can be suitably obtained by a method that further includes steps other than the steps described above. Examples of such other steps include a step of drying the coating film and a step of washing the film before and after the rubbing treatment with a washing liquid.

  As the drying step, a method of heat treatment in an oven or an infrared furnace, a method of heat treatment on a hot plate, and the like are generally known as in the baking step. These methods are also applicable to the drying step. The drying step is preferably performed at a temperature within a range where the solvent can be evaporated, and more preferably at a temperature relatively lower than the temperature in the baking step.

Examples of the cleaning method using the cleaning liquid for the liquid crystal alignment film before and after the alignment treatment include brushing, jet spray, steam cleaning, and ultrasonic cleaning. These methods may be performed alone or in combination. The cleaning liquid is pure water or various alcohols such as methyl alcohol, ethyl alcohol and isopropyl alcohol, aromatic hydrocarbons such as benzene, toluene and xylene, halogen solvents such as methylene chloride, and ketones such as acetone and methyl ethyl ketone. Although it can be used, it is not limited to these. Of course, these cleaning liquids are sufficiently purified and have few impurities. Such a cleaning method can also be applied to the cleaning step in the formation of the liquid crystal alignment film of the present invention.

  Although the film thickness of the liquid crystal aligning film of this invention is not specifically limited, It is preferable that it is 10-300 nm, and it is more preferable that it is 30-150 nm. The film thickness of the liquid crystal alignment film of the present invention can be measured by a known film thickness measuring device such as a step meter or an ellipsometer.

  The liquid crystal display element of the present invention includes a pair of substrates, a liquid crystal layer containing liquid crystal molecules, formed between the pair of substrates, an electrode for applying a voltage to the liquid crystal layer, and the liquid crystal molecules in a predetermined direction. And a liquid crystal alignment film to be aligned. The liquid crystal alignment film of the present invention is used for the liquid crystal alignment film.

  The glass substrate described above with the liquid crystal alignment film of the present invention can be used as the substrate, and the ITO electrode formed on the glass substrate as described above with the liquid crystal alignment film of the present invention can be used as the electrode. Can be used.

  The liquid crystal layer is formed of a liquid crystal composition that is sealed in a gap between a pair of substrates facing each other so that a surface of one of the pair of substrates on which a liquid crystal alignment film is formed faces the other substrate. .

  The liquid crystal composition is not particularly limited, and various liquid crystal compositions having a positive or negative dielectric anisotropy can be used. Preferred liquid crystal compositions having a positive dielectric anisotropy include Japanese Patent No. 3086228, Japanese Patent No. 2635435, Japanese Patent Laid-Open No. 5-501735, Japanese Patent Laid-Open No. 8-157826, and Japanese Patent Laid-Open No. 8-231960. JP-A-9-241644 (EP88272A1 specification), JP-A-9-302346 (EP806466A1 specification), JP-A-8-199168 (EP722998A1 specification), JP-A-9-235552, JP Japanese Laid-Open Patent Publication Nos. 9-255958, 9-241463 (EP882711A1), 10-204016 (EP844229A1), 10-204436, 10-231482, and JP 2000-087040, JP 2001-488 The liquid crystal composition disclosed in 2 publications, and the like.

  Preferred liquid crystal compositions having a negative dielectric anisotropy include JP-A-57-114532, JP-A-2-4725, JP-A-4-222485, JP-A-8-40953, JP-A-8-104869, JP-A-10-168076, JP-A-10-168453, JP-A-10-236989, JP-A-10-236990, JP-A-10-236992, JP-A-10- No. 236993, JP-A-10-236994, JP-A-10-237000, JP-A-10-237004, JP-A-10-237024, JP-A-10-237035, JP-A-10-237075 Publication, Unexamined-Japanese-Patent No. 10-237076, Unexamined-Japanese-Patent No. 10-237448 (EP967261A1 specification), Japanese Laid-Open Patent Publication Nos. 10-287874, 10-287875, 10-291945, 11-029581, 11-080049, 2000-256307, 2001-2001. Examples thereof include liquid crystal compositions disclosed in Japanese Unexamined Patent Application Publication No.

  One or more optically active compounds may be added to the liquid crystal composition having a positive or negative dielectric anisotropy.

  In the liquid crystal display element of the present invention, the liquid crystal alignment film of the present invention is formed on at least one of a pair of substrates, and the obtained pair of substrates are opposed to each other with a liquid crystal alignment film facing inward through a spacer. It is obtained by enclosing a liquid crystal composition in the formed gap to form a liquid crystal layer. The production of the liquid crystal display element of the present invention may include additional steps such as attaching a polarizing film to the substrate as necessary.

  The liquid crystal display element of the present invention can form liquid crystal display elements for various electric field systems. In such a liquid crystal display element for electric field mode, a liquid crystal display element for horizontal electric field mode in which the electrode applies a voltage to the liquid crystal layer in a horizontal direction with respect to the surface of the substrate, or a surface of the substrate In addition, there is a vertical electric field type liquid crystal display element in which the electrode applies a voltage to the liquid crystal layer in the vertical direction.

  Since the liquid crystal display element for the horizontal electric field method does not have to exhibit a relatively large pretilt angle, a side chain structure such as a polyamic acid obtained from a diamine not containing a diamine having a side chain structure or a derivative thereof is used. A liquid crystal alignment film formed from the liquid crystal aligning agent of the present invention containing a polyamic acid not containing benzene or a derivative thereof is suitably used for a liquid crystal display element for a horizontal electric field mode.

  Since the liquid crystal display element for the vertical electric field mode requires a relatively large pretilt angle, a polyamic acid having a side chain structure such as a polyamic acid obtained from a diamine containing a diamine having a side chain structure or a derivative thereof is used. Or the liquid crystal aligning film formed from the liquid crystal aligning agent of this invention containing the derivative (s) is used suitably for the liquid crystal display element for longitudinal electric field systems.

  As described above, the liquid crystal alignment film produced using the liquid crystal aligning agent of the present invention as a raw material can be applied to liquid crystal display elements of various display drive systems by appropriately selecting a polymer as the raw material.

  The liquid crystal display element of the present invention may further include elements other than the above-described components. As such other components, the liquid crystal display element of the present invention is mounted with components usually used for liquid crystal display elements such as a polarizing plate (polarizing film), a wave plate, a light scattering film, and a drive circuit. May be.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. The compounds used in the examples are as follows.

<Tetracarboxylic dianhydride>
Compound (1): pyromellitic dianhydride: PMDA
Compound (19): Cyclobutanetetracarboxylic dianhydride: CBDA

<Diamine>
Compound: 1,2-bis (5-aminobenzoxazole) ethane: ABO (n = 2)
Compound: 1,2-bis (5-aminobenzoxazole) octane: ABO (n = 8)
Compound: o-bis (5-aminobenzoxazole) benzene: o-BO
Compound: m-bis (5-aminobenzoxazole) benzene: m-BO
Compound: p-bis (5-aminobenzimidazole) benzene: p-BI
Compound: o-bis (5-aminobenzimidazole) benzene: o-BI
Compound: m-bis (5-aminobenzimidazole) benzene: m-BI
Compound: 4,4′-diaminodiphenylmethane: DDM
Compound: 4,4′-diaminodiphenyl ether: ODA

<Solvent>
NMP: N-methyl-2-pyrrolidone BC: Butyl cellosolve (ethylene glycol monobutyl ether)

<1. Synthesis of polyamic acid>
[Synthesis Example 1]
1.723 g of compound ABO (n = 2) and 20.0 g of dehydrated NMP were placed in a 100 mL four-necked flask equipped with a thermometer, stirrer, raw material charging inlet and nitrogen gas inlet, and stirred under a dry nitrogen stream. Dissolved. Next, 1.277 g of Compound (1): PMDA and 20.0 g of dehydrated NMP were added, and reacted for 24 hours in a room temperature environment. When the reaction temperature rose during the reaction, the reaction temperature was kept at 40 ° C. or lower for the reaction. 7.0 g of BC was added to the obtained solution to obtain a polyamic acid solution having a concentration of 6.0% by weight. This polyamic acid is designated as PA1. The weight average molecular weight of PA1 was 27,500.

  The weight average molecular weight of the polyamic acid was diluted with a phosphoric acid-DMF mixed solution (phosphoric acid / DMF = 0.6 / 100: weight ratio) so that the polyamic acid concentration was about 1% by weight. Using a 2695 separation module / 2414 differential refractometer (manufactured by Waters), the above mixed solution was measured by a GPC method using a developing agent, and was calculated by polystyrene conversion. In addition, the column used HSPgel RT MB-M (product made from Waters), and measured on conditions with column temperature of 40 degreeC and the flow rate of 0.35 mL / min.

[Synthesis Examples 2 to 14]
Polyamic acid solutions (PA2) to (PA14) were prepared according to Synthesis Example 1 except that tetracarboxylic dianhydride and diamine were changed as shown in Table 1. The results are summarized in Table 1 including Synthesis Example 1.

<2. Production of liquid crystal display element>
[Example 1]
The polyamic acid solution having a concentration of 6.0% by weight synthesized in Synthesis Example 1 was diluted to 4.5% by weight by adding a mixed solvent of NMP / BC = 1/1 (weight ratio) to obtain a liquid crystal aligning agent and did. Using the obtained liquid crystal aligning agent, a liquid crystal display element was produced as follows.

<Method for manufacturing liquid crystal display element>
The liquid crystal aligning agent was applied to two glass substrates with an ITO electrode with a spinner to form a film with a thickness of 70 nm. After coating, the film was heated and dried at 80 ° C. for about 5 minutes, and then heat-treated at 210 ° C. for 20 minutes to form a liquid crystal alignment film. Next, the surface of the substrate on which the liquid crystal alignment film was formed was rubbed with a rubbing apparatus to perform the alignment treatment. Thereafter, the liquid crystal alignment film was ultrasonically cleaned in ultrapure water for 5 minutes and then dried in an oven at 120 ° C. for 30 minutes.

  One glass substrate was sprayed with a 7 μm gap material, and the surface on which the liquid crystal alignment film was formed was placed inside so as to face each other so that the rubbing direction was anti-parallel, and then sealed with an epoxy curing agent, and the gap was 7 μm. A parallel cell was produced. The liquid crystal composition shown below was injected into the cell, and the injection port was sealed with a photocuring agent. Next, a heat treatment was performed at 110 ° C. for 30 minutes to manufacture a liquid crystal display element.

[Examples 2 to 12]
The polyamic acid solution having a concentration of 6.0% by weight synthesized in Synthesis Examples 2 to 12 was diluted to 4.5 to 5.0% by weight by adding a mixed solvent of NMP / BC = 1/1 (weight ratio). Thus, a liquid crystal aligning agent was obtained. A liquid crystal display element was produced in the same manner as in Example 1 using the obtained liquid crystal aligning agent.

[Comparative Examples 1-2]
The polyamic acid solution having a concentration of 6.0% by weight synthesized in Synthesis Examples 13 to 14 was diluted to 4.5% by weight by adding a mixed solvent of NMP / BC = 1/1 (weight ratio) to align the liquid crystal. An agent was used. A liquid crystal display element was produced in the same manner as in Example 1 using the obtained liquid crystal aligning agent.

<3. Evaluation of electrical characteristics>
About the liquid crystal display element produced in Examples 1-12 and Comparative Examples 1-2, the ion density was measured as follows.

1) Measurement of ion density Ion density was measured using a liquid crystal property evaluation apparatus 6254 type manufactured by Toyo Technica. The measurement conditions were waveform: triangular wave, frequency: 0.01 Hz, voltage: ± 10 V, and measurement temperature was 60 ° C. It can be said that the smaller this value, the better the electrical characteristics. The results are shown in Table 2.

  As shown in Table 2, a liquid crystal display device using a liquid crystal alignment film obtained from a liquid crystal alignment agent containing a polyamic acid containing ABO, ABI, BO or BI as a monomer has an effect that the ion density is extremely low. Play.

Claims (15)

In the liquid crystal aligning agent containing polyamic acid or a derivative thereof which is a reaction product of tetracarboxylic dianhydride and diamine,
The diamine is an aromatic oxazole represented by the following general formula (O) -2, an alkyl oxazole represented by the following general formula (O) -3, an aromatic imidazole represented by the following general formula (I) -2 And a liquid crystal aligning agent comprising at least one selected from the group consisting of alkylimidazoles represented by the following general formula (I) -3 .

(In General Formula (O) -3, m represents an integer of 1 to 8.)

(In General Formula (I) -3, m represents an integer of 1 to 8.) 2. The diamine according to claim 1 , further comprising a diamine having at least one side chain structure selected from compounds represented by the following general formulas (VIII) and (X) to (XIII) : Liquid crystal aligning agent.

(In General Formula (VIII), A ³ represents a single bond, —O—, —COO—, —OCO—, —CO—, —CONH—, or — (CH ₂ ) _m — (m is an integer of 1 to 6). R ¹ represents a group having a steroid skeleton, a group represented by the following general formula (IX), and carbon when the positional relationship between two amino groups bonded to the benzene ring is para. In addition, when the positional relationship is meta, it further includes alkyl having 1 to 30 carbons or phenyl, and in the alkyl, any —CH ₂ — is independently —CF ₂ —. , —CHF—, —O— (but discontinuous), —CH═CH— or —C≡C—, where —CH ₃ is —CH ₂ F, —CHF ₂ or —CF ₃ . may be replaced, hydrogen of the phenyl are independently, -F, -CH _3, -OCH ₃ , may be replaced with —OCH ₂ F, —OCHF ₂ or —OCF _3. )

(In General Formula (IX), A ⁴ and A ⁵ are each independently a single bond, —O— (but discontinuous), —COO—, —OCO—, —CONH—, —CH═CH— or carbon. Represents an alkylene of 1 to 12, R ² and R ³ each independently represent —F or —CH ₃ , and ring S independently represents 1,4-phenylene, 1,4-cyclohexylene, 1, 3-dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene-1,5-diyl, naphthalene-2,7-diyl or anthracene-9,10-diyl. R ⁴ represents —H, —F, alkyl having 1 to 30 carbon atoms, fluorine-substituted alkyl having 1 to 30 carbon atoms, alkoxy having 1 to 30 carbon atoms, —CN, —OCH ₂ F, —OCHF ₂ or — It represents OCF _3, integers of the a and b 0 to 4 And, c, d and e represents an integer of 0 to 3, f and g each independently represents an integer of 0 to 2, and is c + d + e ≧ 1.)

(In the general formulas (X) and (XI), R ⁵ independently represents —H or —CH ₃ , R ⁶ represents —H, or alkyl or alkenyl having 1 to 20 carbon atoms, and A ⁶ represents independently And represents a single bond, —C (═O) — or —CH ₂ —, and in the general formula (XI), R ⁷ and R ⁸ each independently represents alkyl having 1 to 20 carbons or phenyl.)

(In the general formulas (XII) and (XIII), A ⁷ independently represents —O— or an alkylene having 1 to 6 carbon atoms, and in the general formula (XII), R ⁹ represents —H or a carbon number of 1 to 30. In the alkyl, an arbitrary —CH ₂ — in the alkyl having 2 to 30 carbon atoms may be replaced by —O— (but discontinuous), —CH═CH— or —C≡C—. Well, A ⁸ represents a single bond or alkylene having 1 to 3 carbon atoms, ring T represents 1,4-phenylene or 1,4-cyclohexylene, h represents 0 or 1, and in general formula (XIII) R ¹⁰ represents alkyl having 6 to 22 carbon atoms, and R ¹¹ represents alkyl having 1 to 22 carbon atoms.) The diamine having the side chain structure is represented by the following general formulas (VIII-2), (VIII-4) to (VIII-6), (XII-2), (XII-4), and (XII-6). The liquid crystal aligning agent according to claim 2 , wherein the liquid crystal aligning agent is at least one selected from the following compounds.

(In the general formula, R ²³ , R ²⁹ and R ³⁰ each represent alkyl having 1 to 30 carbon atoms or alkoxy having 1 to 30 carbon atoms.) The diamine claims 1 to 3, further comprising a diamine which does not have at least one side chain structure selected from the compounds represented by the following general formula (I) ~ (VII) and (XV) Liquid crystal aligning agent as described in any one of these.

(In general formula (I), X represents — (CH ₂ ) _m — (m represents an integer of 1 to 6), and Y is independent in general formulas (III) and (V) to (VII)). Single bond, —O—, —S—, —S—S—, —SO ₂ —, —CO—, —CONH—, —NHCO—, —NH—, —N (CH ₃ ) — (CH _{2) m -N (CH 3)} -, - C (CH 3) 2 -, - C (CF 3) 2 -, - (CH 2) m -, - O- (CH 2) m -O- or - S— (CH ₂ ) _m —S— (m represents an integer of 1 to 6), in general formula (V), Z represents a single bond or none, and in general formula (XV), R ³³ and R ³⁴ each independently represents alkyl or phenyl having 1 to 3 carbon atoms, A ³ independently represents methylene, phenylene or alkyl-substituted phenylene, l represents an integer of 1 to 6, and m represents 1 An integer of ~ 10 And, in the general formula (II) ~ (VII), hydrogen bonded to a cyclohexane ring or benzene ring are each _{independently, -F, -CH 3, -CF 3} , -OH, -COOH, -SO 3 H Alternatively, -PO ₃ H ₂ may be substituted, and hydrogen bonded to the benzene ring in the general formula (IV) may be substituted with benzyl.) The diamine having no side chain structure is represented by the following structural formulas (IV-1), (IV-2), (IV-15) to (IV-17), (V-1) to (V-13), It is at least one selected from the compounds represented by (V-33), (V-35) to (V-37), (VII-2), and (XV-1). 4. A liquid crystal aligning agent according to 4 .

The liquid crystal aligning agent according to claim 1 , wherein the tetracarboxylic dianhydride includes an aromatic tetracarboxylic dianhydride. The aromatic tetracarboxylic dianhydride is at least one of compounds represented by the following structural formulas (1), (2), (5) to (7) and (14). 6. A liquid crystal aligning agent according to 6 .

The liquid crystal aligning agent according to claim 7, wherein the aromatic tetracarboxylic dianhydride is a compound represented by the structural formula (1). The said tetracarboxylic dianhydride contains one or both of an alicyclic tetracarboxylic dianhydride and an aliphatic tetracarboxylic dianhydride, It is any one of Claims 1-8 characterized by the above-mentioned. Liquid crystal aligning agent. The alicyclic tetracarboxylic dianhydride and the aliphatic tetracarboxylic dianhydride are represented by the following structural formulas (19), (23), (25), (35) to (39), (44) and (49). The liquid crystal aligning agent of Claim 9 which is at least 1 of the compound represented by these.

11. The liquid crystal aligning agent according to claim 10 , wherein the alicyclic tetracarboxylic dianhydride and the aliphatic tetracarboxylic dianhydride are compounds represented by the structural formula (19). A liquid crystal aligning agent containing the polyamic acid or its derivatives A and B,
The polyamic acid or derivative A thereof includes the diamine having the side chain structure in the diamine, and is represented by the general formula (O) -2 in one or both of the polyamic acid or diamines A and B thereof. Aromatic oxazole, alkyl oxazole represented by general formula (O) -3, aromatic imidazole represented by general formula (I) -2, and alkyl represented by general formula (I) -3 The liquid crystal aligning agent according to any one of claims 2 to 11 , comprising at least one selected from the group consisting of imidazoles . Alkenyl substituted nadimide compound, a compound having a radical polymerizable unsaturated double bond, oxazine compounds, oxazoline compounds, and any one of claims 1 to 12, characterized in that it further comprises one or more selected from epoxy compounds Liquid crystal aligning agent as described in. The liquid crystal aligning film formed by the coating film of the liquid crystal aligning agent as described in any one of Claims 1-13 being heated. A pair of substrates, a liquid crystal layer containing liquid crystal molecules and formed between the pair of substrates, an electrode for applying a voltage to the liquid crystal layer, and a liquid crystal alignment film for aligning the liquid crystal molecules in a predetermined direction In a liquid crystal display element having
A liquid crystal display element, wherein the liquid crystal alignment film is the liquid crystal alignment film according to claim 14 .