JP2010106091A - Liquid crystal aligning agent, liquid crystal aligned film and liquid crystal display element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a liquid crystal aligning agent useful in providing a liquid crystal display element which achieves the exhibition of a desired voltage holding ratio and its long-term stability. <P>SOLUTION: The liquid crystal aligning agent is a composition containing at least one polymer selected from the group consisting of polyamic acid and a derivative thereof and this polymer is polyamic acid or a derivative thereof obtained by reacting at least one diamine represented by formula (N) (wherein A<SP>1</SP>is independently a 1-10C alkyl, a 1-10C alkoxy, hydroxy, trifluoromethyl, fluorine, chlorine or bromine; m is an integer of 0-3; and A<SP>2</SP>is independently -O-, -NH-, -N(CH<SB>3</SB>)- or -S-) or a mixture of at least one diamine represented by formula (N) and at least another diamine which is a diamine not represented by formula (N) with a tetracarboxylic dianhydride. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a liquid crystal aligning agent containing a polyamic acid obtained by reacting a diamine mainly containing naphthalene in the main chain with a tetracarboxylic dianhydride.

  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 is becoming 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. Currently, the liquid crystal aligning agent mainly used 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 a voltage holding ratio. When the voltage holding ratio is low, the voltage applied to the liquid crystal during the frame period is lowered, and as a result, the luminance is lowered, and normal gradation display may be hindered. Even if the initial voltage holding ratio is high, it is not preferable if the voltage holding ratio (long-term reliability) after the high-temperature acceleration test is lowered.

  As an attempt to solve the above problem, 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). . Moreover, the synthesis method of the polyamic acid obtained by making the aromatic diamine which has naphthalene and tetracarboxylic dianhydride react is known (for example, refer patent document 3). However, further improvements have been demanded in recent liquid crystal alignment films, and there is still room for further study in order to obtain desired electrical characteristics of the obtained liquid crystal alignment film in the liquid crystal alignment agent for forming the liquid crystal alignment film. .

JP 11-193345 A JP-A-11-193347 US5886131 Publication

  The present invention provides a liquid crystal display element that achieves the desired voltage holding ratio and its long-term stability, a liquid crystal alignment film that achieves the desired voltage holding ratio and its long-term stability in the liquid crystal display element, And a liquid crystal aligning agent capable of forming the same.

  In the liquid crystal display element having a liquid crystal alignment film formed by using a polyamic acid or a composition containing a derivative thereof derived from an aromatic diamine having naphthalene as a liquid crystal aligning agent, the present inventors As a result, the inventors have found that a desired voltage holding ratio is expressed, and that good long-term reliability is imparted, and the present invention has been completed.

（ここに、Ａ^１は独立して炭素数１〜１０のアルキル、炭素数１〜１０のアルコキシ、ヒドロキシ、トリフルオロメチル、フッ素、塩素または臭素であり；ｍは独立して０〜３の整数であり；Ａ^２は独立して−Ｏ−、−ＮＨ−、−Ｎ（ＣＨ_３）−、または−Ｓ−であり；そして、２つのアミノ基のベンゼン環への結合位置はＡ^１およびＡ^２の結合位置を除く任意の位置である。） The liquid crystal aligning agent of this invention is shown by the following [1] term.
[1] A composition containing at least one polymer selected from the group consisting of a polyamic acid and a derivative thereof, wherein the polymer is at least one diamine represented by the formula (N) or the formula (N) Liquid crystal alignment which is a polyamic acid or a derivative thereof obtained by reacting a mixture of at least one diamine represented by the formula (N) with at least one other diamine which is not represented by the formula (N) with tetracarboxylic dianhydride Agent.

(Wherein A ¹ is independently alkyl having 1 to 10 carbons, alkoxy having 1 to 10 carbons, hydroxy, trifluoromethyl, fluorine, chlorine or bromine; m is an integer of 0 to 3 independently A ² is independently —O—, —NH—, —N (CH ₃ ) —, or —S—; and the bonding positions of the two amino groups to the benzene ring are A ¹ and A ⁽ It is an arbitrary position excluding the bonding position of ^2. )

  According to the present invention, it is possible to provide a liquid crystal display element that has a high voltage holding ratio and good long-term reliability with respect to a change over time and can be applied to various driving methods.

First, terms used in the present invention will be described.
“Liquid crystal aligning agent” means a composition used for forming a liquid crystal aligning film. The diamine represented by the formula (N) may be referred to as diamine (N). The same applies to diamines represented by other formulas. The tetracarboxylic dianhydride represented by the formula (1) may be referred to as carboxylic acid (1). The same applies to tetracarboxylic dianhydrides represented by other formulas. Other diamine means diamines other than diamine (N). The term “arbitrary” used in describing a chemical structural formula means that not only the position but also the number is arbitrary. And for example, the expression “any A may be replaced by B, C or D” means that any A is replaced by B, any A is replaced by C, and any A is D In addition to the case where it is replaced with, it is meant to include the case where a plurality of A are replaced with at least two of B to D. However, in the case where any —CH ₂ — may be replaced by —O—, the replacement of a plurality of consecutive —CH ₂ — with —O— is not included. A substituent that is not clearly bonded to the atoms constituting the ring is a substituent whose bonding position can be freely determined within a chemically acceptable range. A letter, for example, a symbol in which A is surrounded by a hexagon means ring A.

The present invention comprises the above item [1] and the following items [2] to [20].
[2] The liquid crystal aligning agent according to the item [1], wherein the bonding positions of the two amino groups in the formula (N) are both para to A ² .

（これらの式において、Ｍｅはメチルを意味する。） [3] The diamine is represented by formula (N-1) to formula (N-5), formula (N-7), formula (N-8), formula (N-13), formula (N-15) and formula (N The liquid crystal aligning agent as described in the item [1], which is at least one diamine selected from the compound group represented by -16) or a mixture of this (these) diamine and another diamine.

(In these formulas, Me means methyl.)

[4] In item [3], the diamine is at least one of the diamines represented by formula (N-1) and formula (N-3) or a mixture of this (these) diamine and other diamines. The liquid crystal aligning agent of description.

（ここに、Ａ^３は単結合、−Ｏ−、−ＣＯ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＣＨ_２Ｏ−、−ＣＦ_２Ｏ−、または炭素数１〜６のアルキレンであって、このアルキレンにおける任意の−ＣＨ_２−は−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよく；Ｒ^１はステロイド骨格を有する基、炭素数３〜３０のアルキル、炭素数１〜３０のアルキルもしくは炭素数１〜３０のアルコキシを置換基として有するフェニル、または式（IX）で表される基であって、この炭素数３〜３０のアルキルにおける任意の−ＣＨ_２−は−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよい。）

（ここに、Ａ^４およびＡ^５は独立して単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、炭素数１〜４のアルキレン、炭素数１〜３のオキシアルキレン、または炭素数１〜３のアルキレンオキシであり；環Ｂおよび環Ｃは独立して１，４−フェニレンまたは１，４−シクロヘキシレンであり；Ｒ^２およびＲ^３は独立してフッ素またはメチルであって、ｆおよびｇは独立して０、１または２であり；ｃ、ｄおよびｅは独立して０〜３の整数であって、これらの合計は１以上であり；Ｒ^４は炭素数１〜３０のアルキル、炭素数１〜３０のアルコキシ、または炭素数２〜３０のアルコキシアルキルであり、これらのアルキル、アルコキシおよびアルコキシアルキルにおいて、任意の水素はフッ素で置き換えられてもよく、そして任意の−ＣＨ_２−はジフルオロメチレンで置き換えられてもよい。）

（式（Ｘ）および式（ＸＩ）において、Ｒ^５は独立して水素またはメチルであり、Ｒ^６は水素または炭素数１〜２０のアルキルもしくはアルケニルであり、Ｒ^７およびＲ^８はそれぞれ独立して炭素数１〜２０のアルキルまたはフェニルであり、Ａ^６は独立して単結合、−ＣＯ−または−ＣＨ_２−である。）

（式（XII）および式（XIII）において、Ｒ^９は炭素数１〜３０のアルキルであって、このアルキルの任意の−ＣＨ_２−は、−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよく；Ｒ^１０は炭素数６〜２２のアルキルであり；Ｒ^１１は炭素数１〜２２のアルキルであり；Ａ^７は独立して−Ｏ−または炭素数１〜６のアルキレンであり；Ａ^８は単結合または炭素数１〜３のアルキレンであり；環Ｔは１，４−フェニレンまたは１，４−シクロヘキシレンであり；ｈは０または１である。） [5] Diamine is a mixture of at least one diamine represented by formula (N) and another diamine, and the other diamine is represented by formula (VIII) or formula (X) to formula (XIII). The liquid crystal aligning agent as described in the item [1], which is at least one diamine having a side chain group selected from the group.

(Here, ^{A 3} is a single bond, -O -, - CO -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CF 2 O-, or an alkylene having 1 to 6 carbon atoms And any —CH ₂ — in the alkylene may be replaced by —O—, —CH═CH— or —C≡C—; R ¹ is a group having a steroid skeleton, having 3 to 30 carbon atoms Or an alkyl having 1 to 30 carbon atoms or phenyl having 1 to 30 carbon atoms as a substituent, or a group represented by the formula (IX), —CH ₂ — may be replaced by —O—, —CH═CH— or —C≡C—.

(Wherein A ⁴ and A ⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, oxyalkylene having 1 to 3 carbons, or C 1-3 alkyleneoxy; ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; R ² and R ³ are independently fluorine or methyl; , f and g are independently 0, 1 or 2; c, d and e is an integer of 0 to 3 independently, their sum is 1 or more; ^{R 4} is 1 to carbon atoms 30 alkyls, alkoxys having 1 to 30 carbons, or alkoxyalkyls having 2 to 30 carbons, and in these alkyls, alkoxys and alkoxyalkyls, any hydrogen may be replaced by fluorine, and any CH ₂ - may be replaced by difluoromethylene).

(In Formula (X) and Formula (XI), R ⁵ is independently hydrogen or methyl, R ⁶ is hydrogen or alkyl or alkenyl having 1 to 20 carbon atoms, and R ⁷ and R ⁸ are each independently C 6-20 alkyl or phenyl, A ⁶ is independently a single bond, —CO— or —CH ₂ —.)

(In Formula (XII) and Formula (XIII), R ⁹ is alkyl having 1 to 30 carbon atoms, and any —CH ₂ — in the alkyl is —O—, —CH═CH—, or —C≡. R ¹⁰ is alkyl having 6 to 22 carbon atoms; R ¹¹ is alkyl having 1 to 22 carbon atoms; A ⁷ is independently —O— or 1 to 6 carbon atoms. A ⁸ is a single bond or alkylene having 1 to 3 carbon atoms; ring T is 1,4-phenylene or 1,4-cyclohexylene; h is 0 or 1)

（これらの式において、Ｒ^２３、Ｒ^２９およびＲ^３０はそれぞれ炭素数１〜３０のアルキルまたは炭素数１〜３０のアルコキシである。） [6] The diamine is represented by formula (N-1) to formula (N-5), formula (N-7), formula (N-8), formula (N-13), formula (N-15) and formula (N -16) is a mixture of at least one diamine selected from the group of compounds represented by formula (VIII) and other diamines, and the other diamines are represented by formula (VIII-2), formula (VIII-4) to formula (VIII-6). The liquid crystal according to item [3], which is at least one of diamines having a side chain group selected from diamines represented by formula (XII-2), formula (XII-4) and formula (XII-6) Alignment agent.

(In these formulas, R ²³ , R ²⁹ and R ³⁰ are each an alkyl having 1 to 30 carbon atoms or an alkoxy having 1 to 30 carbon atoms.)

（これらの式において、Ｘは炭素数２〜１２の直鎖アルキレンであり；Ｙは独立して単結合、−Ｏ−、−ＣＯ−、−ＮＨ−、−Ｎ（ＣＨ_３）−、−ＣＯＮＨ−、−ＮＨＣＯ−、−Ｃ（ＣＨ_３）_２−、−Ｃ（ＣＦ_３）_２−、−Ｏ−（ＣＨ_２）_ｔ−Ｏ−、−Ｓ−、−Ｓ−Ｓ−、−ＳＯ_２−、−Ｓ−（ＣＨ_２）_ｔ−Ｓ−または炭素数１〜１２の直鎖アルキレンであって、ｔは１〜１２の整数であり；Ｚ^１およびＺ^２は水素であるが、Ｙが−ＮＨ−、−Ｎ（ＣＨ_３）−、−ＣＨ_２−、−Ｃ（ＣＨ_３）_２−または−Ｃ（ＣＦ_３）_２−であるときには互いに結合して単結合を形成してもよく；環Ｄはフェニレンまたは１，４−ジアザシクロヘキシレンであり；Ｒ^３３およびＲ^３４はそれぞれ独立して炭素数１〜３のアルキルまたはフェニルであり；Ａ^３は独立して炭素数１〜６のアルキレン、フェニレンまたはアルキル置換されたフェニレンであり；ｍは１〜１０の整数であり；シクロヘキサン環またはベンゼン環の任意の水素は、フッ素、メチル、−ＯＨ、−ＣＯＯＨ、−ＳＯ_３Ｈ、−ＰＯ_３Ｈ_２、ベンジルまたはヒドロキシベンジルで置き換えられてもよい。） [7] A mixture in which the diamine further contains a diamine having no side chain group, wherein the diamine having no side chain group is represented by the formula (I) to the formula (VII) and the formula (XV) The liquid crystal aligning agent according to any one of [1] to [6], which is at least one selected from the group.

(In these formulas, X is a linear alkylene having 2 to 12 carbon atoms; Y is independently a single bond, —O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH. _{-, - NHCO -, - C} (CH 3) 2 -, - C (CF 3) 2 -, - O- (CH 2) t -O -, - S -, - S-S -, - SO 2 - , —S— (CH ₂ ) _t —S— or a linear alkylene having 1 to 12 carbon atoms, t is an integer of 1 to 12; Z ¹ and Z ² are hydrogen, and Y is — When NH—, —N (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) ₂ — or —C (CF ₃ ) ₂ —, they may combine with each other to form a single bond; D is phenylene or ^{1,4-diaza-cyclohexylene; R 33} and ^{R 34} alkyl addition of 1 to 3 carbon atoms are each independently Phenyl; A ³ is independently an alkylene having 1 to 6 carbon atoms, be phenylene or alkyl-substituted phenylene; m is an integer from 1 to 10; any hydrogen cyclohexane ring or benzene ring, fluorine , Methyl, —OH, —COOH, —SO ₃ H, —PO ₃ H ₂ , benzyl or hydroxybenzyl.

[8] Diamine having no side chain group is represented by formula (IV-1), formula (IV-2), formula (IV-15) to formula (IV-17), formula (V-1) to formula (V- 12), diamines represented by formula (V-33), formula (V-35) to formula (V-37), formula (VI-7), formula (VII-2) and formula (XV-1). The liquid crystal aligning agent according to item [7], which is at least one.

（ここに、Ａ^３は単結合、−Ｏ−、−ＣＯ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＣＨ_２Ｏ−、−ＣＦ_２Ｏ−、または炭素数１〜６のアルキレンであって、このアルキレンにおける任意の−ＣＨ_２−は−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよく；Ｒ^１はステロイド骨格を有する基、炭素数３〜３０のアルキル、炭素数１〜３０のアルキルもしくは炭素数１〜３０のアルコキシを置換基として有するフェニル、または式（IX）で表される基であって、この炭素数３〜３０のアルキルにおける任意の−ＣＨ_２−は−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよい。）

（ここに、Ａ^４およびＡ^５は独立して単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、炭素数１〜４のアルキレン、炭素数１〜３のオキシアルキレン、または炭素数１〜３のアルキレンオキシであり；環Ｂおよび環Ｃは独立して１，４−フェニレンまたは１，４−シクロヘキシレンであり；Ｒ^２およびＲ^３は独立してフッ素またはメチルであって、ｆおよびｇは独立して０、１または２であり；ｃ、ｄおよびｅは独立して０〜３の整数であって、これらの合計は１以上であり；Ｒ^４は炭素数１〜３０のアルキル、炭素数１〜３０のアルコキシ、または炭素数２〜３０のアルコキシアルキルであり、これらのアルキル、アルコキシおよびアルコキシアルキルにおいて、任意の水素はフッ素で置き換えられてもよく、そして任意の−ＣＨ_２−はジフルオロメチレンで置き換えられてもよい。）

（式（Ｘ）および式（ＸＩ）において、Ｒ^５は独立して水素またはメチルであり、Ｒ^６は水素または炭素数１〜２０のアルキルもしくはアルケニルであり、Ｒ^７およびＲ^８はそれぞれ独立して炭素数１〜２０のアルキルまたはフェニルであり、Ａ^６は独立して単結合、−ＣＯ−または−ＣＨ_２−である。）

（式（XII）および式（XIII）において、Ｒ^９は炭素数１〜３０のアルキルであって、このアルキルの任意の−ＣＨ_２−は、−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよく；Ｒ^１０は炭素数６〜２２のアルキルであり；Ｒ^１１は炭素数１〜２２のアルキルであり；Ａ^７は独立して−Ｏ−または炭素数１〜６のアルキレンであり；Ａ^８は単結合または炭素数１〜３のアルキレンであり；環Ｔは１，４−フェニレンまたは１，４−シクロヘキシレンであり；ｈは０または１である。）

（これらの式において、Ｘは炭素数２〜１２の直鎖アルキレンであり；Ｙは独立して単結合、−Ｏ−、−ＣＯ−、−ＮＨ−、−Ｎ（ＣＨ_３）−、−ＣＯＮＨ−、−ＮＨＣＯ−、−Ｃ（ＣＨ_３）_２−、−Ｃ（ＣＦ_３）_２−、−Ｏ−（ＣＨ_２）_ｔ−Ｏ−、−Ｓ−、−Ｓ−Ｓ−、−ＳＯ_２−、−Ｓ−（ＣＨ_２）_ｔ−Ｓ−または炭素数１〜１２の直鎖アルキレンであって、ｔは１〜１２の整数であり；Ｚ^１およびＺ^２は水素であるが、Ｙが−ＮＨ−、−Ｎ（ＣＨ_３）−、−ＣＨ_２−、−Ｃ（ＣＨ_３）_２−または−Ｃ（ＣＦ_３）_２−であるときには互いに結合して単結合を形成してもよく；環Ｄはフェニレンまたは１，４−ジアザシクロヘキシレンであり；Ｒ^３３およびＲ^３４はそれぞれ独立して炭素数１〜３のアルキルまたはフェニルであり；Ａ^３は独立して炭素数１〜６のアルキレン、フェニレンまたはアルキル置換されたフェニレンであり；ｍは１〜１０の整数であり；シクロヘキサン環またはベンゼン環の任意の水素は、フッ素、メチル、−ＯＨ、−ＣＯＯＨ、−ＳＯ_３Ｈ、−ＰＯ_３Ｈ_２、ベンジルまたはヒドロキシベンジルで置き換えられてもよい。） [9] The polymer is at least one diamine represented by formula (N) and at least one diamine having a side chain group selected from the diamine group represented by formula (VIII) and formula (X) to formula (XIII). At least 1 of the diamine which has a side chain group chosen from the diamine group represented by a mixture with one or at least 1 of the diamine represented by Formula (N), and Formula (VIII) and Formula (X)-Formula (XIII) And a mixture of at least one diamine having no side chain group selected from the diamine group represented by formula (I) to formula (VII) and formula (XV) is reacted with tetracarboxylic dianhydride. At least one of the diamines having no side chain group or at least one of the diamines having no side chain group and at least one of the diamines represented by the formula (N) The liquid crystal aligning agent as described in the item [1], which is a mixture with a polyamic acid or a derivative thereof obtained by reacting a mixture with one with a tetracarboxylic dianhydride.

(Here, ^{A 3} is a single bond, -O -, - CO -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CF 2 O-, or an alkylene having 1 to 6 carbon atoms And any —CH ₂ — in the alkylene may be replaced by —O—, —CH═CH— or —C≡C—; R ¹ is a group having a steroid skeleton, having 3 to 30 carbon atoms Or an alkyl having 1 to 30 carbon atoms or phenyl having 1 to 30 carbon atoms as a substituent, or a group represented by the formula (IX), —CH ₂ — may be replaced by —O—, —CH═CH— or —C≡C—.

(Wherein A ⁴ and A ⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, oxyalkylene having 1 to 3 carbons, or C 1-3 alkyleneoxy; ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; R ² and R ³ are independently fluorine or methyl; , f and g are independently 0, 1 or 2; c, d and e is an integer of 0 to 3 independently, their sum is 1 or more; ^{R 4} is 1 to carbon atoms 30 alkyls, alkoxys having 1 to 30 carbons, or alkoxyalkyls having 2 to 30 carbons, and in these alkyls, alkoxys and alkoxyalkyls, any hydrogen may be replaced by fluorine, and any CH ₂ - may be replaced by difluoromethylene).

(In Formula (X) and Formula (XI), R ⁵ is independently hydrogen or methyl, R ⁶ is hydrogen or alkyl or alkenyl having 1 to 20 carbon atoms, and R ⁷ and R ⁸ are each independently C 6-20 alkyl or phenyl, A ⁶ is independently a single bond, —CO— or —CH ₂ —.)

(In Formula (XII) and Formula (XIII), R ⁹ is alkyl having 1 to 30 carbon atoms, and any —CH ₂ — in the alkyl is —O—, —CH═CH—, or —C≡. R ¹⁰ is alkyl having 6 to 22 carbon atoms; R ¹¹ is alkyl having 1 to 22 carbon atoms; A ⁷ is independently —O— or 1 to 6 carbon atoms. A ⁸ is a single bond or alkylene having 1 to 3 carbon atoms; ring T is 1,4-phenylene or 1,4-cyclohexylene; h is 0 or 1)

(In these formulas, X is a linear alkylene having 2 to 12 carbon atoms; Y is independently a single bond, —O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH. _{-, - NHCO -, - C} (CH 3) 2 -, - C (CF 3) 2 -, - O- (CH 2) t -O -, - S -, - S-S -, - SO 2 - , —S— (CH ₂ ) _t —S— or a linear alkylene having 1 to 12 carbon atoms, t is an integer of 1 to 12; Z ¹ and Z ² are hydrogen, and Y is — When NH—, —N (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) ₂ — or —C (CF ₃ ) ₂ —, they may combine with each other to form a single bond; D is phenylene or ^{1,4-diaza-cyclohexylene; R 33} and ^{R 34} alkyl addition of 1 to 3 carbon atoms are each independently Phenyl; A ³ is independently an alkylene having 1 to 6 carbon atoms, be phenylene or alkyl-substituted phenylene; m is an integer from 1 to 10; any hydrogen cyclohexane ring or benzene ring, fluorine , Methyl, —OH, —COOH, —SO ₃ H, —PO ₃ H ₂ , benzyl or hydroxybenzyl.

（ここに、Ａ^３は単結合、−Ｏ−、−ＣＯ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＣＨ_２Ｏ−、−ＣＦ_２Ｏ−、または炭素数１〜６のアルキレンであって、このアルキレンにおける任意の−ＣＨ_２−は−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよく；Ｒ^１はステロイド骨格を有する基、炭素数３〜３０のアルキル、炭素数１〜３０のアルキルもしくは炭素数１〜３０のアルコキシを置換基として有するフェニル、または式（IX）で表される基であって、この炭素数３〜３０のアルキルにおける任意の−ＣＨ_２−は−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよい。）

（ここに、Ａ^４およびＡ^５は独立して単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、炭素数１〜４のアルキレン、炭素数１〜３のオキシアルキレン、または炭素数１〜３のアルキレンオキシであり；環Ｂおよび環Ｃは独立して１，４−フェニレンまたは１，４−シクロヘキシレンであり；Ｒ^２およびＲ^３は独立してフッ素またはメチルであって、ｆおよびｇは独立して０、１または２であり；ｃ、ｄおよびｅは独立して０〜３の整数であって、これらの合計は１以上であり；Ｒ^４は炭素数１〜３０のアルキル、炭素数１〜３０のアルコキシ、または炭素数２〜３０のアルコキシアルキルであり、これらのアルキル、アルコキシおよびアルコキシアルキルにおいて、任意の水素はフッ素で置き換えられてもよく、そして任意の−ＣＨ_２−はジフルオロメチレンで置き換えられてもよい。）

（式（Ｘ）および式（ＸＩ）において、Ｒ^５は独立して水素またはメチルであり、Ｒ^６は水素または炭素数１〜２０のアルキルもしくはアルケニルであり、Ｒ^７およびＲ^８はそれぞれ独立して炭素数１〜２０のアルキルまたはフェニルであり、Ａ^６は独立して単結合、−ＣＯ−または−ＣＨ_２−である。）

（式（XII）および式（XIII）において、Ｒ^９は炭素数１〜３０のアルキルであって、このアルキルの任意の−ＣＨ_２−は、−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられてもよく；Ｒ^１０は炭素数６〜２２のアルキルであり；Ｒ^１１は炭素数１〜２２のアルキルであり；Ａ^７は独立して−Ｏ−または炭素数１〜６のアルキレンであり；Ａ^８は単結合または炭素数１〜３のアルキレンであり；環Ｔは１，４−フェニレンまたは１，４−シクロヘキシレンであり；ｈは０または１である。）

（これらの式において、Ｘは炭素数２〜１２の直鎖アルキレンであり；Ｙは独立して単結合、−Ｏ−、−ＣＯ−、−ＮＨ−、−Ｎ（ＣＨ_３）−、−ＣＯＮＨ−、−ＮＨＣＯ−、−Ｃ（ＣＨ_３）_２−、−Ｃ（ＣＦ_３）_２−、−Ｏ−（ＣＨ_２）_ｔ−Ｏ−、−Ｓ−、−Ｓ−Ｓ−、−ＳＯ_２−、−Ｓ−（ＣＨ_２）_ｔ−Ｓ−または炭素数１〜１２の直鎖アルキレンであって、ｔは１〜１２の整数であり；Ｚ^１およびＺ^２は水素であるが、Ｙが−ＮＨ−、−Ｎ（ＣＨ_３）−、−ＣＨ_２−、−Ｃ（ＣＨ_３）_２−または−Ｃ（ＣＦ_３）_２−であるときには互いに結合して単結合を形成してもよく；環Ｄはフェニレンまたは１，４−ジアザシクロヘキシレンであり；Ｒ^３３およびＲ^３４はそれぞれ独立して炭素数１〜３のアルキルまたはフェニルであり；Ａ^３は独立して炭素数１〜６のアルキレン、フェニレンまたはアルキル置換されたフェニレンであり；ｍは１〜１０の整数であり；シクロヘキサン環またはベンゼン環の任意の水素は、フッ素、メチル、−ＯＨ、−ＣＯＯＨ、−ＳＯ_３Ｈ、−ＰＯ_３Ｈ_２、ベンジルまたはヒドロキシベンジルで置き換えられてもよい。） [10] A polymer having at least one diamine represented by formula (N) and a diamine having no side chain group selected from the diamine group represented by formula (I) to formula (VII) and formula (XV). A polyamic acid obtained by reacting a mixture of at least one with tetracarboxylic dianhydride or a derivative thereof, and a side chain selected from the diamine group represented by formula (VIII) and formula (X) to formula (XIII) Polyamic acid obtained by reacting a mixture of at least one diamine having a group or at least one diamine having a side chain group and at least one diamine having no side chain group with tetracarboxylic dianhydride Alternatively, the liquid crystal aligning agent according to the item [1], which is a mixture with a derivative thereof.

(Here, ^{A 3} is a single bond, -O -, - CO -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CF 2 O-, or an alkylene having 1 to 6 carbon atoms And any —CH ₂ — in the alkylene may be replaced by —O—, —CH═CH— or —C≡C—; R ¹ is a group having a steroid skeleton, having 3 to 30 carbon atoms Or an alkyl having 1 to 30 carbon atoms or phenyl having 1 to 30 carbon atoms as a substituent, or a group represented by the formula (IX), —CH ₂ — may be replaced by —O—, —CH═CH— or —C≡C—.

(Wherein A ⁴ and A ⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, oxyalkylene having 1 to 3 carbons, or C 1-3 alkyleneoxy; ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; R ² and R ³ are independently fluorine or methyl; , f and g are independently 0, 1 or 2; c, d and e is an integer of 0 to 3 independently, their sum is 1 or more; ^{R 4} is 1 to carbon atoms 30 alkyls, alkoxys having 1 to 30 carbons, or alkoxyalkyls having 2 to 30 carbons, and in these alkyls, alkoxys and alkoxyalkyls, any hydrogen may be replaced by fluorine, and any CH ₂ - may be replaced by difluoromethylene).

(In Formula (X) and Formula (XI), R ⁵ is independently hydrogen or methyl, R ⁶ is hydrogen or alkyl or alkenyl having 1 to 20 carbon atoms, and R ⁷ and R ⁸ are each independently C 6-20 alkyl or phenyl, A ⁶ is independently a single bond, —CO— or —CH ₂ —.)

(In Formula (XII) and Formula (XIII), R ⁹ is alkyl having 1 to 30 carbon atoms, and any —CH ₂ — in the alkyl is —O—, —CH═CH—, or —C≡. R ¹⁰ is alkyl having 6 to 22 carbon atoms; R ¹¹ is alkyl having 1 to 22 carbon atoms; A ⁷ is independently —O— or 1 to 6 carbon atoms. A ⁸ is a single bond or alkylene having 1 to 3 carbon atoms; ring T is 1,4-phenylene or 1,4-cyclohexylene; h is 0 or 1)

(In these formulas, X is a linear alkylene having 2 to 12 carbon atoms; Y is independently a single bond, —O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH. _{-, - NHCO -, - C} (CH 3) 2 -, - C (CF 3) 2 -, - O- (CH 2) t -O -, - S -, - S-S -, - SO 2 - , —S— (CH ₂ ) _t —S— or a linear alkylene having 1 to 12 carbon atoms, t is an integer of 1 to 12; Z ¹ and Z ² are hydrogen, and Y is — When NH—, —N (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) ₂ — or —C (CF ₃ ) ₂ —, they may combine with each other to form a single bond; D is phenylene or ^{1,4-diaza-cyclohexylene; R 33} and ^{R 34} alkyl addition of 1 to 3 carbon atoms are each independently Phenyl; A ³ is independently an alkylene having 1 to 6 carbon atoms, be phenylene or alkyl-substituted phenylene; m is an integer from 1 to 10; any hydrogen cyclohexane ring or benzene ring, fluorine , Methyl, —OH, —COOH, —SO ₃ H, —PO ₃ H ₂ , benzyl or hydroxybenzyl.

（これらの式において、Ｍｅはメチルを意味する。）

（これらの式において、Ｒ^２３、Ｒ^２９およびＲ^３０はそれぞれ炭素数１〜３０のアルキルまたは炭素数１〜３０のアルコキシである。）

[11] The diamine represented by formula (N) is represented by formula (N-1) to formula (N-5), formula (N-7), formula (N-8), formula (N-13), formula (N). N-15) or a diamine represented by formula (N-16), and a diamine having a side chain group is represented by formula (VIII-2), formula (VIII-4) to formula (VIII-6), or formula (XII). -2), a diamine represented by formula (XII-4) or formula (XII-6), and a diamine having no side chain group is represented by formula (IV-1), formula (IV-2), formula ( IV-15) to formula (IV-17), formula (V-1) to formula (V-12), formula (V-33), formula (V-35) to formula (V-37), formula (VI -7) The liquid crystal aligning agent as described in the item [9] or [10], which is a diamine represented by the formula (VII-2) or the formula (XV-1).

(In these formulas, Me means methyl.)

(In these formulas, R ²³ , R ²⁹ and R ³⁰ are each an alkyl having 1 to 30 carbon atoms or an alkoxy having 1 to 30 carbon atoms.)

[12] The tetracarboxylic dianhydride is an aromatic tetracarboxylic dianhydride or a mixture of an aromatic tetracarboxylic dianhydride and a non-aromatic tetracarboxylic dianhydride, [1] to [11] ] The liquid crystal aligning agent of any one of.

[13] The aromatic tetracarboxylic dianhydride is selected from the group of compounds represented by formula (1), formula (2), formula (5) to formula (7), formula (11) and formula (14). The liquid crystal aligning agent according to item [12], which is at least one.

[14] The liquid crystal aligning agent according to the item [13], wherein the aromatic tetracarboxylic dianhydride is a compound represented by the formula (1).

[15] The liquid crystal aligning agent according to the item [12], wherein the tetracarboxylic dianhydride other than aromatic is an alicyclic tetracarboxylic dianhydride and / or an aliphatic tetracarboxylic dianhydride.

[16] The aromatic tetracarboxylic dianhydride is selected from the group of compounds represented by formula (1), formula (2), formula (5) to formula (7), formula (11) and formula (14). And at least one non-aromatic tetracarboxylic dianhydride is represented by formula (19), formula (23), formula (25), formula (35) to formula (39), formula (44) and formula (44) 49) The liquid crystal aligning agent according to item [12], which is at least one selected from the group of compounds represented by 49).

[17] The aromatic tetracarboxylic dianhydride is a compound represented by the formula (1), and the non-aromatic tetracarboxylic dianhydride is a compound represented by the formula (19). [16] A liquid crystal aligning agent according to item.

[18] Any of [1] to [17], further comprising at least one compound 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 2. A liquid crystal aligning agent according to item 1.

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

[20] 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 item [19].

  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). Examples of this polyamic acid derivative are soluble polyimide, polyamic acid ester, polyamic acid amide, and the like. More specifically, 1) a polyimide in which polyamic acid is completely dehydrated and closed, 2) partial polyimide in which dehydration and ring closure reaction is partially performed, 3) polyamic acid ester in which carboxyl of polyamic acid is converted to ester, 4) tetracarboxylic A polyamic acid-polyamide copolymer obtained by reacting a mixture of an acid dianhydride and an organic dicarboxylic acid; and 5) a polyamideimide obtained by dehydrating and ring-closing a part or all of this polyamic acid-polyamide copolymer. . A preferred example of the polyamic acid derivative is polyimide. The liquid crystal aligning agent of the present invention is a composition containing at least one polymer selected from the group consisting of a polyamic acid and a derivative of such a polyamic acid.

In the present invention, at least one diamine represented by the formula (N) is used.

In the formula (N), A ¹ is independently alkyl having 1 to 10 carbons, alkoxy having 1 to 10 carbons, hydroxy, trifluoromethyl, fluorine, chlorine or bromine. Preferred examples of A ¹ are alkyl having 1 to 3 carbons, alkoxy having 1 to 3 carbons, hydroxy and trifluoromethyl. More preferred examples of A ¹ are methyl, methoxy, hydroxy and trifluoromethyl. m is independently an integer of 0 to 3, preferably both 0 or 1. A ² is independently —O—, —NH—, —N (CH ₃ ) —, or —S—. The two A ² are preferably the same linking group. The bonding position of the two amino groups to the benzene ring is an arbitrary position excluding the bonding positions of A ¹ and A ² , and both are preferably bonded to the para position with respect to A ² .

（これらの式におけるＭｅはメチルを意味する。） Preferred examples of the diamine (N) are shown below.

(Me in these formulas means methyl.)

  Among the above diamines, diamine (N-1) to diamine (N-5), diamine (N-7), diamine (N-8), diamine (N-13), diamine (N-15), and diamine (N-16) is preferable, and diamine (N-1) and diamine (N-3) are more preferable.

  When producing the polymer in the liquid crystal aligning agent of the present invention, only the diamine (N) may be used, or a mixture of this diamine and another diamine, that is, a diamine not represented by the formula (N) may be used. . The proportion of the diamine (N) used is 5 to 100 with respect to the total amount of diamine used when producing the polymer 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 it is mol%, and it is more preferable that it is 5-50 mol%.

  By the way, other diamines can be classified into two types depending on the difference in structure. That is, when a skeleton connecting two amino groups is viewed as a main chain, a group branched from the main chain, that is, a diamine having a side chain group and a diamine having no side chain group. By reacting a diamine having a side chain group with tetracarboxylic dianhydride, a polyamic acid or polyimide having a large number of side chain groups with respect to the main chain of the polymer is obtained. When a polyamic acid or polyimide having a side chain group with respect to such a polymer main chain is used, the liquid crystal alignment film formed from the liquid crystal aligning agent containing this polymer increases the pretilt angle in the liquid crystal display element. Can do. That is, this side chain group is a group having an effect of increasing the pretilt angle. The side chain group having such an effect needs to be a group having 3 or more carbon atoms. Specific examples include alkyl having 3 or more carbon atoms, alkoxy having 3 or more carbon atoms, alkoxyalkyl having 3 or more carbon atoms, and A group having a steroid skeleton can be exemplified. A group having one or more rings, wherein the terminal ring has any one of alkyl having 1 or more carbon atoms, alkoxy having 1 or more carbon atoms and alkoxyalkyl having 2 or more carbon atoms as a substituent; It has an effect as a side chain group. The side chain group in the present invention is selected from these groups. In the following description, a diamine having such a side chain group may be referred to as a side chain diamine. A diamine having no side chain group having 3 or more carbon atoms may be referred to as a non-side chain diamine.

  Then, by properly using the side chain diamine and the non-side chain diamine, it is possible to cope with the pretilt angle required for each of the various display elements. That is, in the vertical electric field method represented by the TN method and the VA method, a relatively large pretilt angle is required, and therefore, a side chain type diamine is mainly used. At this time, in order to further control the pretilt angle, a non-side chain diamine may be used in combination. What is necessary is just to determine the compounding ratio of non-side chain type diamine and side chain type diamine according to the magnitude | size of the target pretilt angle. Of course, it is possible to use only a side chain type diamine by appropriately selecting a side chain group. In the lateral electric field method, since the pretilt angle is small and high liquid crystal orientation is required, at least one of non-side chain diamines may be used. As described above, the liquid crystal aligning agent of the present invention can be applied to any kind of liquid crystal display element.

Specific examples of the side chain group are as follows.
First, alkyl, alkyloxy, alkyloxyalkyl, alkylcarbonyl, alkylcarbonyloxy, alkyloxycarbonyl, alkylaminocarbonyl, alkenyl, alkenyloxy, alkenylcarbonyl, alkenylcarbonyloxy, alkenyloxycarbonyl, alkenylaminocarbonyl, alkynyl, Alkynyloxy, alkynylcarbonyl, alkynylcarbonyloxy, alkynyloxycarbonyl, alkynylaminocarbonyl and the like can be mentioned. Alkyl, alkenyl and alkynyl in these groups are all groups having 3 or more carbon atoms. However, in alkyloxyalkyl, it is sufficient if it has 3 or more carbon atoms as a whole. These groups may be linear or branched.

  Next, phenyl, phenylalkyl, phenylalkyloxy, phenyloxy, provided that the terminal ring has alkyl having 1 or more carbon atoms, alkoxy having 1 or more carbon atoms or alkoxyalkyl having 2 or more carbon atoms as a substituent. Phenylcarbonyl, phenylcarbonyloxy, phenyloxycarbonyl, phenylaminocarbonyl, phenylcyclohexyloxy, cycloalkyl having 3 or more carbon atoms, cyclohexylalkyl, cyclohexyloxy, cyclohexyloxycarbonyl, cyclohexylphenyl, cyclohexylphenylalkyl, cyclohexylphenyloxy, bis ( Cyclohexyl) oxy, bis (cyclohexyl) alkyl, bis (cyclohexyl) phenyl, bis (cyclohexyl) phenylalkyl, bis ( Kurohekishiru) oxycarbonyl, and bis (cyclohexyl) phenyloxycarbonyl and cyclohexyl bis (phenyl) group of a ring structure, such as oxycarbonyl,.

  Further, a group having two or more benzene rings, a group having two or more cyclohexane rings, or two or more groups composed of a benzene ring and a cyclohexane ring, wherein the bonding groups are independently a single bond, -O-, -COO-, -OCO-, -CONH-, or alkylene having 1 to 3 carbon atoms, the terminal ring is alkyl having 1 or more carbon atoms as a substituent, fluorine-substituted alkyl having 1 or more carbon atoms, carbon A ring assembly group having an alkoxy of several or more or an alkoxyalkyl having two or more carbons can be given. Of course, a group having a steroid skeleton is also effective as a side chain group.

Preferable examples of the side chain diamine are diamines represented by formula (VIII) and formula (X) to formula (XIII).

In formula (VIII), ^{A 3} is a single bond, -O -, - CO -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CF 2 O-, or 6 carbon atoms And any —CH ₂ — in the alkylene may be replaced by —O—, —CH═CH— or —C≡C—. Preferred examples of A ³ are a single bond, —O—, —COO—, —OCO—, —CH ₂ O—, and alkylene having 1 to 3 carbon atoms, and particularly preferred examples are a single bond, —O—, — _{COO -, - OCO -, -} CH 2 O -, - CH 2 - and _-CH 2 CH ₂ -. R ¹ is a group having a steroid skeleton, alkyl having 3 to 30 carbon atoms, phenyl having 1 to 30 carbon atoms or alkoxy having 1 to 30 carbon atoms as a substituent, or a group represented by the formula (IX) In the alkyl having 3 to 30 carbon atoms, any —CH ₂ — may be replaced by —O—, —CH═CH— or —C≡C—. Preferred examples of R ¹ are alkyl having 3 to 30 carbon atoms, alkyl having 1 to 30 carbon atoms or phenyl having 1 to 30 carbon atoms as a substituent, and a group represented by formula (IX). The bonding positions of the two amino groups with the benzene ring are preferably the 3-position and 5-position or the 2-position and 5-position when the bonding position of A ³ is the 1-position.

In the formula (IX), A ⁴ and A ⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, or oxyalkylene having 1 to 3 carbons. Or alkyleneoxy having 1 to 3 carbon atoms, preferably a single bond or alkylene having 1 to 4 carbon atoms. Ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene. R ² and R ³ are independently fluorine or methyl. f and g are each independently 0, 1 or 2, preferably 0. c, d and e are each independently an integer of 0 to 3, and the sum thereof is 1 or more. R ⁴ is alkyl having 1 to 30 carbons, alkoxy having 1 to 30 carbons, or alkoxyalkyl having 2 to 30 carbons, and in these alkyls, alkoxys and alkoxyalkyls, any hydrogen is replaced with fluorine. And any —CH ₂ — may be replaced by difluoromethylene. Preferred examples of R ⁴ are alkyl having 1 to 30 carbons and alkoxy having 1 to 30 carbons.

In formula (X) and formula (XI), R ⁵ is independently hydrogen or methyl. R ⁶ is hydrogen, alkyl having 1 to 20 carbons or alkenyl having 2 to 20 carbons. R ⁷ and R ⁸ are each independently alkyl having 1 to 20 carbons or phenyl. A ⁶ is independently a single bond, —CO— or —CH ₂ —. In the formula (X), it is preferable that one of the two “NH ₂ —Ph—A ⁶ —O—” is bonded to the 3-position of the steroid skeleton and the other is bonded to the 6-position. The coupling position of the benzene ring of the two amino groups is preferably both with respect to the binding position of A ^6, meta or para position. In the formula (XI), the bonding positions of the two “NH ₂ — (R ⁶ —) Ph—A ⁶ —O—” with the benzene ring are all meta positions relative to the carbon to which the steroid skeleton is bonded. The para position is preferred. The coupling position of the benzene ring of the two amino groups is preferably both with respect to the binding position of A ^6, meta or para position.

In the formulas (XII) and (XIII), R ⁹ is alkyl having 1 to 30 carbons, and any —CH ₂ — in the alkyl is —O—, —CH═CH—, or —C≡C. It may be replaced with-. R ¹⁰ is alkyl having 6 to 22 carbon atoms, and R ¹¹ is alkyl having 1 to 22 carbon atoms. A ⁷ is independently —O— or alkylene having 1 to 6 carbons. A ⁸ represents a single bond or alkylene having 1 to 3 carbon atoms. Ring T is 1,4-phenylene or 1,4-cyclohexylene. h is 0 or 1. In the formula (XII), bonding position of the benzene ring of the two amino groups is preferably either a meta or para position with respect to the binding position of A ^7. In the formula (XIII), bonding position of the benzene ring of the two amino groups is preferably either a meta or para position with respect to the binding position of A ^7.

Specific examples of diamine (VIII) are shown below.

In the formulas (VIII-1) to (VIII-11), R ²³ is alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, preferably alkyl having 5 to 25 carbons or 5 to 5 carbons. 25 alkoxy. R ²⁴ is alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, preferably alkyl having 3 to 25 carbons or alkoxy having 3 to 25 carbons.

In Formula (VIII-12) to Formula (VIII-17), R ²⁵ is alkyl having 4 to 30 carbons, and preferably alkyl having 6 to 25 carbons. R ²⁶ is alkyl having 6 to 30 carbon atoms, preferably alkyl having 8 to 25 carbon atoms.

In the formula (VIII-18) to the formula (VIII-37), R ²⁷ is alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, preferably alkyl having 3 to 25 carbons or carbon 3 ~ 25 alkoxy. R ²⁸ is hydrogen, fluorine, alkyl having 1 to 30 carbons, alkoxy having 1 to 30 carbons, —CN, —OCH ₂ F, —OCHF ₂ or —OCF ₃ , preferably alkyl having 3 to 25 carbons. Or it is C3-C25 alkoxy.

  Among the above diamines (VIII-1) to diamines (VIII-43), diamines (VIII-1) to diamines (VIII-11) are preferable, and diamines (VIII-2) and diamines (VIII-4) to diamines ( VIII-6) is more preferable.

Specific examples of diamine (X) are shown below.

Specific examples of diamine (XI) are shown below.

Specific examples of diamine (XII) are shown below.

In formula (XII-1) to formula (XII-3), R ²⁹ is alkyl having 1 to 30 carbons or alkoxy having 1 to 30 carbons, preferably alkyl having 3 to 30 carbons or 3 to 3 carbons. 30 alkoxy. In the formulas (XII-4) to (XII-8), R ³⁰ is alkyl having 1 to ³⁰ carbons or alkoxy having 1 to 30 carbons, preferably alkyl having 3 to 30 carbons or 3 to 3 carbons. 30 alkoxy.

Specific examples of diamine (XIII) are shown below.

In Formula (XIII-1) to Formula (XIII-3), R ³¹ is alkyl having 6 to 22 carbons, and preferably alkyl having 6 to 20 carbons. R ³² is alkyl having 1 to 22 carbons, preferably alkyl having 1 to 10 carbons.

  Among the specific examples of the side chain diamine, diamine (VIII-2), diamine (VIII-4) to diamine (VIII-6), diamine (XII-2), diamine (XII-4) and diamine (XII) -6) is preferred.

  When the side chain type diamine as described above is intended to develop a large pretilt angle in a liquid crystal display element, when the polymer used in the liquid crystal aligning agent of the present invention is produced, the ratio in the total amount of diamine is 1 to It is preferable to set it as 90 mol%, and it is more preferable to set it as 5-70 mol%.

Preferable examples of the diamine having no side chain group as described above, that is, a non-side chain diamine include compounds represented by the formulas (I) to (VII) and (XV).

In these formulas, X is a linear alkylene having 2 to 12 carbon atoms. Y is independently a single bond, —O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) _2- , -O- (CH ₂ ) _t -O-, -S-, -S-S-, -SO _2- , -S- (CH ₂ ) _t -S-, or a straight chain having 1 to 12 carbon atoms. Chain alkylene, t is an integer of 1-12. Z ¹ and Z ² are hydrogen, but when Y is —NH—, —N (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) ₂ — or —C (CF ₃ ) ₂ —. They may be bonded together to form a single bond. Ring D is phenylene or 1,4-diazacyclohexylene. R ³³ and R ³⁴ are each independently alkyl or phenyl having 1 to 3 carbon atoms. A ³ is independently alkylene having 1 to 6 carbon atoms, phenylene, or alkyl-substituted phenylene. m is an integer of 1-10. Any hydrogen in the cyclohexane or benzene ring may be replaced with fluorine, methyl, —OH, —COOH, —SO ₃ H, —PO ₃ H ₂ , benzyl or hydroxybenzyl.

Examples of diamine (I) are shown below.

Specific examples of diamine (II) are shown below.

Specific examples of diamine (III) are shown below.

Specific examples of diamine (IV) are shown below.

Specific examples of diamine (V) are shown below.

Specific examples of diamine (VI) are shown below.

Specific examples of diamine (VII) are shown below.

Specific examples of diamine (XV) are shown below.

  Among the above-mentioned non-side chain diamines, diamine (IV-1) to diamine (IV-5), diamine (IV-15) to diamine (IV-17), diamine (V-1) to diamine (V-12) ), Diamine (V-26), diamine (V-27), diamine (V-31), diamine (V-33), diamine (V-35) to diamine (V-37), diamine (VI-1) Diamine (VI-2), diamine (VI-6), diamine (VII-1) to diamine (VII-5) and diamine (XV-1) are preferred, and diamine (IV-1) and diamine (IV-2). ), Diamine (IV-15) to diamine (IV-17), diamine (V-1) to diamine (V-12), diamine (V-33), diamine (V-35) to diamine (V-37) , Diamine (VI-7), diamine (VII-2) and diamine (XV-1) Is more preferable.

  Such non-side chain type diamine is 1 to 98 in terms of molar ratio in the total amount of diamine as a raw material of 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. %, Preferably 10 to 95%.

  Diamines other than the diamine (I) to diamine (VIII), diamine (X) to diamine (XIII), and diamine (XV) can be used as the diamine used in the present invention. Examples of such diamines include fluorene diamines having a fluorene ring and side chain diamines other than diamine (VIII) to diamine (XII).

これらの式において、Ｒ^３５およびＲ^３６はそれぞれ独立して炭素数３〜３０のアルキル基である。これらのジアミンは、本発明の液晶配向剤におけるポリアミック酸を製造する際に、本発明の効果が損なわれない程度の範囲で用いることができる。 Examples of the side chain diamine other than diamine (VIII) to diamine (XII) are diamine (1 ′) to diamine (8 ′).

In these formulas, R ³⁵ and R ³⁶ are each independently an alkyl group having 3 to 30 carbon atoms. These diamines can be used in such a range that the effects of the present invention are not impaired when the polyamic acid in the liquid crystal aligning agent of the present invention is produced.

  When producing a polyamic acid, a monoamine may be added to the diamine. By adding a monoamine, termination of the polymerization reaction when producing the polyamic acid can be caused, and further progress of the polymerization reaction can be suppressed. That is, the molecular weight of the obtained polymer (polyamic acid or derivative thereof) can be easily controlled, and for example, the coating properties of the liquid crystal aligning agent can be improved without impairing the effects of the present invention. What is necessary is just to adjust the addition ratio of a monoamine suitably considering the molecular weight of the target polyamic acid. If the effects of the present invention are not impaired, two or more monoamines may be added. Examples of monoamines are aniline, 4-hydroxyaniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecyl. Amine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, and n-eicosylamine .

In the following description excluding examples, unless otherwise specified, “polyamic acid” is used as a general term for polyamic acid and its derivatives.
In the present invention, when a diamine is reacted with tetracarboxylic dianhydride to obtain a polyamic acid, a mixture of diamine (N) and other diamine can be used as described above. At this time, one of the preferable examples of the other diamine is at least one of side chain type diamines selected from the group of diamine (VIII) and diamine (X) to diamine (XIII). Another preferred example of the other diamines includes diamine (VIII) and at least one side chain diamine selected from the group of diamine (X) to diamine (XIII) and diamine (I) to diamine (VII) and diamine ( XV) is a mixture with at least one non-side chain diamine selected from the group of XV). The above items [5] to [8] are preferred examples of the combination of diamine (N), side chain diamine and non-side chain diamine.

  In the present invention, the polyamic acid obtained by reacting the mixed diamine with tetracarboxylic acid as described above may be used as the polymer component, or a mixture of polyamic acids of different raw materials may be used as the polymer component. One preferred example of the polyamic acid mixture is a mixture of at least one of diamine (N) and at least one of diamine (VIII) and a side chain diamine selected from the group of diamine (X) to diamine (XIII), or Polyamics obtained by reacting a mixture of diamine (I) to diamine (VII) and at least one non-side chain diamine selected from the group of diamine (XV) with tetracarboxylic dianhydride A polyamic acid obtained by reacting an acid with a mixture of at least one of the non-side chain diamines or at least one of the non-side chain diamines and at least one of the diamines (N) with a tetracarboxylic dianhydride And a mixture.

  Another preferred example of the polyamic acid mixture is at least one of diamine (N) and at least one non-side chain diamine selected from the group consisting of diamine (I) to diamine (VII) and diamine (XV). Polyamic acid obtained by reacting a mixture with tetracarboxylic dianhydride, and at least one of side chain type diamines selected from the group of diamine (VIII) and diamine (X) to diamine (XIII), or this side chain type It is a mixture of polyamic acid obtained by reacting a mixture of at least one of diamines and at least one of the above-mentioned non-side chain diamines with tetracarboxylic dianhydride. In the above [9] to [11], preferred examples in which the polymer component is a mixture of polyamic acids are described.

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

Examples of aromatic tetracarboxylic dianhydrides are shown below.

  Of the above aromatic tetracarboxylic dianhydrides, carboxylic acid (1), carboxylic acid (2), carboxylic acid (5) to carboxylic acid (7), carboxylic acid (11) and carboxylic acid (14) are preferred. Carboxylic acid (1) is particularly preferred.

Examples of alicyclic tetracarboxylic dianhydrides are shown below.

  Among the alicyclic tetracarboxylic dianhydrides, carboxylic acid (19), carboxylic acid (25), carboxylic acid (35) to carboxylic acid (37), carboxylic acid (39), carboxylic acid (44) and Carboxylic acid (49) is preferred, and carboxylic acid (19) is more preferred.

Examples of aliphatic tetracarboxylic dianhydrides are shown below. Of the following examples, carboxylic acid (23) is preferred.

  In this invention, tetracarboxylic dianhydrides other than said carboxylic acid (1) -carboxylic acid (67) can also be used. Examples thereof include tetracarboxylic dianhydride having a side chain group. By using tetracarboxylic dianhydride having a side chain group, the pretilt angle in the liquid crystal display element can be increased. Examples of the tetracarboxylic dianhydride having a side chain group include carboxylic acid (68) and carboxylic acid (69) having a steroid skeleton.

  When manufacturing a polyamic acid, you may use it, adding a dicarboxylic acid anhydride to tetracarboxylic dianhydride. By doing so, termination of the polymerization reaction at the time of producing the polyamic acid can be caused, and further progress of the polymerization reaction can be suppressed. That is, the molecular weight of the resulting polymer (polyamic acid) can be easily controlled, and for example, the coating properties of the liquid crystal aligning agent can be improved without impairing the effects of the present invention. What is necessary is just to adjust suitably the addition ratio of dicarboxylic acid anhydride in consideration of the molecular weight of the target polyamic acid. Further, two or more kinds of dicarboxylic acid anhydrides may be added as long as the effects of the present invention are not impaired. Examples of dicarboxylic acid anhydrides are maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, n-tetradecyl succinic anhydride, n- Hexadecyl succinic anhydride and cyclohexane anhydride.

  In the present invention, a monoisocyanate compound may be further added when producing a polyamic acid. By adding a monoisocyanate compound, the terminal of the resulting polyamic acid is modified, and the molecular weight is adjusted. By using this terminal-modified polyamic acid, for example, the coating properties of the liquid crystal aligning agent can be improved without impairing the effects of the present invention. The addition amount of the monoisocyanate compound is preferably 1 to 10 mol% with respect to the total amount of diamine and tetracarboxylic dianhydride from the above viewpoint. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

  The polyamic acid used in the present invention can be produced in the same manner as a known polyamic acid used for forming a polyimide film. 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 is preferably a weight average molecular weight (Mw) in terms of polystyrene of 10,000 to 500,000, and more preferably 20,000 to 200,000. The molecular weight of the polyamic acid can be determined from a measured value by a gel permeation chromatography (GPC) method.

  The presence of polyamic acid can be confirmed by analyzing the solid content obtained by precipitation with a large amount of poor solvent by IR or NMR. The raw material used can be confirmed by decomposing polyamic acid with an aqueous solution of strong alkali such as KOH and NaOH and analyzing the extract of the decomposed product with an organic solvent by GC, HPLC or GC-MS. .

  The liquid crystal aligning agent of this invention may further contain other components other than the said polyamic acid. 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. Preferred examples of this alkenyl-substituted nadiimide compound are shown below.

  The liquid crystal aligning agent of this invention may further contain the compound which has a radically polymerizable unsaturated double bond from a viewpoint which stabilizes the electrical property of a liquid crystal display element for a long term, for example. 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. A (meth) acrylic acid derivative having two or more bonds is more preferred.

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. Examples of the oxazine compound include compounds represented by formula (a) to formula (f).

In formula (a) to formula (f), 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 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) a m -S-, m is an integer from 1 to 6; Y is independently And a single bond, —O—, —S—, —CO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, or alkylene having 1 to 3 carbon atoms.

  The liquid crystal aligning agent of this invention may further contain the epoxy compound which has a 1 or 2 or more epoxy ring in a molecule | numerator from a viewpoint of the long-term stability of the electrical property in a liquid crystal display element, for example. This epoxy compound may be a monomer, oligomer or polymer having an epoxy ring.

  The liquid crystal aligning agent of the present invention may further contain various additives. Examples of the various additives include polymers other than polyamic acid and its derivatives, and low molecular weight compounds, which can be selected and used according to their respective purposes. Examples of the polymer include polymers that are soluble in organic solvents. It is preferable to add such a polymer 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 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 coating properties is desired, 2) an antistatic agent when improvement in antistatic properties is required, and 3) adhesion to the substrate. When improvement in rubbing resistance is desired, a silane coupling agent or a titanium-based coupling agent, and 4) an imidization catalyst when imidization proceeds at a low temperature.

  Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyltri Methoxysilane, paraaminophenyltrimethoxysilane, paraaminophenyltriethoxysilane, metaaminophenyltrimethoxysilane, metaaminophenyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-chloropropylmethyl Dimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, N- (1,3-dimethylbutylidene) -3- (to Triethoxysilyl) -1-propylamine, and N, N'-bis [3- (trimethoxysilyl) propyl] ethylenediamine.

  Examples of imidation catalysts include aliphatic amines such as trimethylamine, triethylamine, tripropylamine, and tributylamine; aromatic amines such as N, N-dimethylaniline, N, N-diethylaniline, methyl-substituted aniline, and hydroxy-substituted aniline. And 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, and hydroxy-substituted imidazole. . The imidation catalyst is selected from N, N-dimethylaniline, o-hydroxyaniline, m-hydroxyaniline, p-hydroxyaniline, o-hydroxypyridine, m-hydroxypyridine, p-hydroxypyridine, and isoquinoline. It is preferable that it is 1 type, or 2 or more types.

  The liquid crystal aligning agent of the present invention may further contain a solvent from the viewpoint of the application property of the liquid crystal aligning agent and the adjustment of the concentration of the polyamic acid. This solvent can be applied without any particular limitation as long as it has the ability to dissolve the polymer component. The said solvent contains the solvent normally used in the manufacturing process and application 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 such a solvent include a parent solvent for the polyamic acid and other solvents for improving coating properties.

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

  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 monomethyl Dipropylene glycol monoalkyl ethers such as ethers and esters such as these acetates Compounds, and the like.

  Among these, particularly preferred solvents are N-methyl-2-pyrrolidone, N, N-dimethylacetamide, dimethylimidazolidinone, γ-butyrolactone, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl. Ether, and dipropylene glycol monomethyl ether.

  In the present invention, the concentration of the polymer component containing the polyamic acid 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 a substrate, an operation of diluting a polymer component contained therein in advance with a solvent may be required for film thickness adjustment. 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 film 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 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.

  Firing of the coating film can be performed under conditions necessary for the polyamic acid to exhibit dehydration and ring closure reactions. As 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 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-treating in an oven or an infrared furnace, a method of heat-treating 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, vapor cleaning, and ultrasonic cleaning. These methods may be performed alone or in combination. The cleaning liquid is pure water, various alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol, aromatic hydrocarbons such as benzene, toluene, 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 contains a pair of substrates and liquid crystal molecules, a liquid crystal layer formed between the pair of substrates, an electrode for applying a voltage to the liquid crystal layer, and the liquid crystal molecules aligned in a predetermined direction. And the liquid crystal alignment film of the present invention.

  The glass substrate described above in 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 in the liquid crystal alignment film of the present invention can be used as the electrode. it can. The liquid crystal layer is formed of a liquid crystal composition that is sealed between substrates having a liquid crystal alignment film surface inside.

  The liquid crystal composition to be used 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, 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 Unexamined 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.

  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.

  A liquid crystal display element for a horizontal electric field method may not exhibit a relatively large pretilt angle. Therefore, a liquid crystal alignment film formed from a liquid crystal aligning agent containing a non-side chain type polyamic acid obtained by using a non-side chain type diamine is suitably used for a liquid crystal display element for a horizontal electric field mode.

  A liquid crystal display element for a vertical electric field system requires a relatively large pretilt angle. Therefore, a liquid crystal alignment film formed from a liquid crystal alignment agent containing a side chain type polyamic acid obtained by using a side chain type diamine or a diamine mixture containing the same is suitably used for a liquid crystal display element for a vertical electric field mode. It is done.

  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>
Carboxylic acid (1): pyromellitic dianhydride carboxylic acid (19): 1,2,3,4-cyclobutanetetracarboxylic dianhydride

<Diamine>
Diamine (VI-7): 1,4-bis (4-aminophenyl) -1,4-diazacyclohexanediamine (V-1): 4,4′-diaminodiphenylmethanediamine (V-7): 1,2 -Bis (4-aminophenyl) ethanediamine (XII-4-1): 1,1-bis [4- (4-aminophenoxy) phenyl-4- (trans-4-n-pentylcyclohexyl) cyclohexanediamine (XII) 2-1): 1,1-bis [4- (4-aminophenylmethyl) phenyl] -4-n-heptylcyclohexanediamine (N-1): 1,4-bis (4-aminophenoxy) naphthalenediamine (V-36): N, N′-bis (4-aminophenyl) -N, N′-dimethylethylenediamine

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

<1. Synthesis of polyamic acid>
[Synthesis Example 1]
2.100 g of diamine (VI-7), 1.072 g of diamine (N-1), 1.072 g of diamine (XII-) in a 100 mL four-necked flask equipped with a thermometer, stirrer, raw material charging inlet and nitrogen gas inlet 2-1) 0.569 g and dehydrated NMP 80.0 g were added and dissolved by stirring under a dry nitrogen stream. Next, 0.683 g of carboxylic acid (1) and 1.434 g of carboxylic acid (19) were added and reacted in a room temperature environment for 30 hours. When the reaction temperature rose during the reaction, the reaction temperature was kept at about 70 ° C. or lower for the reaction. BC14.0g was added to the obtained solution, and the polyamic acid solution with a density | concentration of 6 weight% was obtained. This polyamic acid is referred to as PA1. The weight average molecular weight of PA1 was 40,100.

  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 7]
Polyamic acid solutions (PA2) to (PA7) 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.

<Table 1>

<2. Production of liquid crystal display element>
[Example 1]
The polyamic acid solution (PA1) having a concentration of 6% by weight synthesized in Synthesis Example 1 was added to a mixed solvent of NMP / BC = 1/1 (weight ratio) to dilute the whole to 4% by weight to obtain a liquid crystal aligning agent. . 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.

<Liquid crystal composition>

[Example 2]
The polyamic acid solution (PA2) having a concentration of 6% by weight synthesized in Synthesis Example 2 was diluted to 4% by weight by adding a mixed solvent of NMP / BC = 1/1 (weight ratio) to obtain a liquid crystal aligning agent. . A liquid crystal display element was produced in the same manner as in Example 1 using the obtained liquid crystal aligning agent.

[Example 3]
A 6 wt% polyamic acid solution (PA3) synthesized in Synthesis Example 3 was added to a mixed solvent of NMP / BC = 1/1 (weight ratio) to dilute the whole to 4 wt% to obtain a liquid crystal aligning agent. . A liquid crystal display element was produced in the same manner as in Example 1 using the obtained liquid crystal aligning agent.

[Comparative Example 1]
A 6 wt% polyamic acid solution (PA4) synthesized in Synthesis Example 4 was added to a mixed solvent of NMP / BC = 1/1 (weight ratio) to dilute the whole to 4 wt% to obtain a liquid crystal aligning agent. . A liquid crystal display element was produced in the same manner as in Example 1 using the obtained liquid crystal aligning agent.

[Comparative Example 2]
The polyamic acid solution (PA5) with a concentration of 6% by weight synthesized in Synthesis Example 5 was added to a mixed solvent of NMP / BC = 1/1 (weight ratio) to dilute the whole to 4% by weight to obtain a liquid crystal aligning agent. . A liquid crystal display element was produced in the same manner as in Example 1 using the obtained liquid crystal aligning agent.

[Comparative Example 3]
The polyamic acid solution (PA6) having a concentration of 6% by weight synthesized in Synthesis Example 6 was diluted with a mixed solvent of NMP / BC = 1/1 (weight ratio) to 4% by weight to obtain a liquid crystal aligning agent. . A liquid crystal display element was produced in the same manner as in Example 1 using the obtained liquid crystal aligning agent.

[Comparative Example 4]
A 6 wt% polyamic acid solution (PA7) synthesized in Synthesis Example 7 was added to a mixed solvent of NMP / BC = 1/1 (weight ratio) to dilute the whole to 4 wt% to obtain a liquid crystal aligning agent. . 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 1-3 and Comparative Examples 1-4, the measurement of the voltage holding rate and the long-term reliability were performed as follows.

1) Measurement of voltage holding ratio The voltage holding ratio was measured using a liquid crystal property evaluation apparatus 6254 type manufactured by Toyo Technica. Measurement conditions were gate width: 60 μs, frequency: 3 Hz, wave height: ± 1 V, and measurement temperature was 60 ° C. It can be said that the higher this value, the better the electrical characteristics. The results are shown in Table 2.

2) Measurement of holding characteristics of voltage holding ratio With respect to the manufactured liquid crystal display element, the voltage holding ratio [%] was obtained over time, and the holding characteristics were evaluated. As a test method for holding characteristics, a method was adopted in which the liquid crystal display element was left in an atmosphere at a temperature of 100 ° C., and the voltage holding ratio [%] was measured over time. It can be said that the smaller the decrease in the voltage holding ratio (for example, the lowering ratio according to the following equation is less than 10%), the better the holding characteristic of the voltage holding ratio and the better the long-term reliability of the electrical characteristics.
Reduction rate (%) = (initial (0 hour) voltage holding ratio−500 hours later voltage holding ratio) / initial voltage holding ratio × 100
The data after 300 hours and after 500 hours are shown in Table 2.

<Table 2>

  As shown in Table 2, when a polyamic acid is produced using a raw material diamine containing diamine (N), the liquid crystal display element using the liquid crystal aligning agent containing this polymer as a liquid crystal alignment film has a voltage holding. The effect of suppressing the rate decrease over time was significantly improved.

Claims (20)

A composition containing at least one polymer selected from the group consisting of a polyamic acid and a derivative thereof, wherein the polymer is represented by at least one diamine represented by the formula (N) or the formula (N). A liquid crystal aligning agent which is a polyamic acid or a derivative thereof obtained by reacting a mixture of at least one diamine and at least one other diamine which is a diamine not represented by the formula (N) with tetracarboxylic dianhydride.

(Wherein A ¹ is independently alkyl having 1 to 10 carbons, alkoxy having 1 to 10 carbons, hydroxy, trifluoromethyl, fluorine, chlorine or bromine; m is an integer of 0 to 3 independently A ² is independently —O—, —NH—, —N (CH ₃ ) —, or —S—; and the bonding positions of the two amino groups to the benzene ring are A ¹ and A ⁽ It is an arbitrary position excluding the bonding position of ^2. ) Is para with respect to the binding position are both A ² of the two amino groups in formula (N), the liquid crystal aligning agent of claim 1. The diamine is represented by formula (N-1) to formula (N-5), formula (N-7), formula (N-8), formula (N-13), formula (N-15) and formula (N-16). The liquid crystal aligning agent of Claim 1 which is a mixture of at least 1 diamine chosen from the compound group represented by these, or this (these) diamine and other diamine.

(In these formulas, Me means methyl.)   The liquid crystal aligning agent of Claim 3 whose diamine is a mixture of at least 1 of the diamine represented by Formula (N-1) and Formula (N-3), or this (these) diamine and another diamine. . The diamine is a mixture of at least one diamine represented by the formula (N) and another diamine, and the other diamine is selected from the diamine group represented by the formula (VIII) and the formulas (X) to (XIII). The liquid crystal aligning agent of Claim 1 which is at least 1 of the diamine which has a side chain group.

(Here, ^{A 3} is a single bond, -O -, - CO -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CF 2 O-, or an alkylene having 1 to 6 carbon atoms And any —CH ₂ — in the alkylene may be replaced by —O—, —CH═CH— or —C≡C—; R ¹ is a group having a steroid skeleton, having 3 to 30 carbon atoms Or an alkyl having 1 to 30 carbon atoms or phenyl having 1 to 30 carbon atoms as a substituent, or a group represented by the formula (IX), —CH ₂ — may be replaced by —O—, —CH═CH— or —C≡C—.

(Wherein A ⁴ and A ⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, oxyalkylene having 1 to 3 carbons, or C 1-3 alkyleneoxy; ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; R ² and R ³ are independently fluorine or methyl; , f and g are independently 0, 1 or 2; c, d and e is an integer of 0 to 3 independently, their sum is 1 or more; ^{R 4} is 1 to carbon atoms 30 alkyls, alkoxys having 1 to 30 carbons, or alkoxyalkyls having 2 to 30 carbons, and in these alkyls, alkoxys and alkoxyalkyls, any hydrogen may be replaced by fluorine, and any CH ₂ - may be replaced by difluoromethylene).

(In Formula (X) and Formula (XI), R ⁵ is independently hydrogen or methyl, R ⁶ is hydrogen, alkyl having 1 to 20 carbons or alkenyl having 2 to 20 carbons, R ⁷ and R ⁸ is each independently alkyl or phenyl having 1 to 20 carbon atoms, and A ⁶ is independently a single bond, —CO— or —CH ₂ —.)

(In Formula (XII) and Formula (XIII), R ⁹ is alkyl having 1 to 30 carbon atoms, and any —CH ₂ — in the alkyl is —O—, —CH═CH—, or —C≡. R ¹⁰ is alkyl having 6 to 22 carbon atoms; R ¹¹ is alkyl having 1 to 22 carbon atoms; A ⁷ is independently —O— or 1 to 6 carbon atoms. A ⁸ is a single bond or alkylene having 1 to 3 carbon atoms; ring T is 1,4-phenylene or 1,4-cyclohexylene; h is 0 or 1) The diamine is represented by formula (N-1) to formula (N-5), formula (N-7), formula (N-8), formula (N-13), formula (N-15) and formula (N-16). And a mixture of at least one diamine selected from the group of compounds represented by formula (VIII-2), formula (VIII-4) to formula (VIII-6), formula (VIII) The liquid crystal aligning agent of Claim 3 which is at least 1 of the diamine which has a side chain group chosen from the diamine represented by XII-2), Formula (XII-4), and Formula (XII-6).

(In these formulas, R ²³ , R ²⁹ and R ³⁰ are each an alkyl having 1 to 30 carbon atoms or an alkoxy having 1 to 30 carbon atoms.) A mixture in which the diamine further contains a diamine having no side chain group, and the diamine having no side chain group is selected from the group of compounds represented by formulas (I) to (VII) and (XV) The liquid crystal aligning agent of any one of Claims 1-6 which is at least 1 which is said.

(In these formulas, X is a linear alkylene having 2 to 12 carbon atoms; Y is independently a single bond, —O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH. _{-, - NHCO -, - C} (CH 3) 2 -, - C (CF 3) 2 -, - O- (CH 2) t -O -, - S -, - S-S -, - SO 2 - , —S— (CH ₂ ) _t —S— or a linear alkylene having 1 to 12 carbon atoms, t is an integer of 1 to 12; Z ¹ and Z ² are hydrogen, and Y is — When NH—, —N (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) ₂ — or —C (CF ₃ ) ₂ —, they may combine with each other to form a single bond; D is phenylene or ^{1,4-diaza-cyclohexylene; R 33} and ^{R 34} alkyl addition of 1 to 3 carbon atoms are each independently Phenyl; A ³ is independently an alkylene having 1 to 6 carbon atoms, be phenylene or alkyl-substituted phenylene; m is an integer from 1 to 10; any hydrogen cyclohexane ring or benzene ring, fluorine , Methyl, —OH, —COOH, —SO ₃ H, —PO ₃ H ₂ , benzyl or hydroxybenzyl. Diamines having no side chain groups are represented by formula (IV-1), formula (IV-2), formula (IV-15) to formula (IV-17), formula (V-1) to formula (V-12), At least one of the diamines represented by formula (V-33), formula (V-35) to formula (V-37), formula (VI-7), formula (VII-2) and formula (XV-1) The liquid crystal aligning agent of Claim 7 which is.

The polymer comprises at least one diamine represented by the formula (N) and at least one diamine having a side chain group selected from the diamine group represented by the formula (VIII) and the formula (X) to the formula (XIII). At least one diamine represented by the mixture or formula (N) and at least one diamine having a side chain group selected from the diamine group represented by formula (VIII) and formula (X) to formula (XIII) and formula ( A polyamic acid obtained by reacting a mixture of at least one diamine having no side chain group selected from the diamine group represented by I) to formula (VII) and formula (XV) with tetracarboxylic dianhydride Or a derivative thereof, at least one diamine having no side chain group, or at least one diamine having no side chain group, and at least one diamine represented by the formula (N), The mixture is a mixture of polyamic acid or a derivative thereof obtained by reacting a tetracarboxylic dianhydride, a liquid crystal aligning agent of claim 1.

(Here, ^{A 3} is a single bond, -O -, - CO -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CF 2 O-, or an alkylene having 1 to 6 carbon atoms And any —CH ₂ — in the alkylene may be replaced by —O—, —CH═CH— or —C≡C—; R ¹ is a group having a steroid skeleton, having 3 to 30 carbon atoms Or an alkyl having 1 to 30 carbon atoms or phenyl having 1 to 30 carbon atoms as a substituent, or a group represented by the formula (IX), —CH ₂ — may be replaced by —O—, —CH═CH— or —C≡C—.

(Wherein A ⁴ and A ⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, oxyalkylene having 1 to 3 carbons, or C 1-3 alkyleneoxy; ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; R ² and R ³ are independently fluorine or methyl; , f and g are independently 0, 1 or 2; c, d and e is an integer of 0 to 3 independently, their sum is 1 or more; ^{R 4} is 1 to carbon atoms 30 alkyls, alkoxys having 1 to 30 carbons, or alkoxyalkyls having 2 to 30 carbons, and in these alkyls, alkoxys and alkoxyalkyls, any hydrogen may be replaced by fluorine, and any CH ₂ - may be replaced by difluoromethylene).

(In Formula (X) and Formula (XI), R ⁵ is independently hydrogen or methyl, R ⁶ is hydrogen or alkyl or alkenyl having 1 to 20 carbon atoms, and R ⁷ and R ⁸ are each independently C 6-20 alkyl or phenyl, A ⁶ is independently a single bond, —CO— or —CH ₂ —.)

(In Formula (XII) and Formula (XIII), R ⁹ is alkyl having 1 to 30 carbon atoms, and any —CH ₂ — in the alkyl is —O—, —CH═CH—, or —C≡. R ¹⁰ is alkyl having 6 to 22 carbon atoms; R ¹¹ is alkyl having 1 to 22 carbon atoms; A ⁷ is independently —O— or 1 to 6 carbon atoms. A ⁸ is a single bond or alkylene having 1 to 3 carbon atoms; ring T is 1,4-phenylene or 1,4-cyclohexylene; h is 0 or 1)

(In the formulas (I) to (VII) and (XV), X is a linear alkylene having 2 to 12 carbon atoms; Y is independently a single bond, —O—, —CO—, —NH—; , —N (CH ₃ ) —, —CONH—, —NHCO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, —O— (CH ₂ ) _t —O—, —S— _{, -S-S -, - SO} 2 -, - S- (CH 2) a t -S- or straight chain alkylene of 1 to 12 carbon atoms, t is an integer from 1 to 12; ^{Z 1} and Z ² is hydrogen, but bonded to each other when Y is —NH—, —N (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) ₂ — or —C (CF ₃ ) ₂ —. It may form a single bond Te; ring D is phenylene or 1,4-diaza-cyclohexylene; R ³³ and R ³⁴ are each independently carbon Be a 1-3 alkyl or phenyl; A ³ is independently an alkylene having 1 to 6 carbon atoms, be phenylene or alkyl-substituted phenylene; m is an integer from 1 to 10; cyclohexane ring or benzene ring Any hydrogen may be replaced by fluorine, methyl, —OH, —COOH, —SO ₃ H, —PO ₃ H ₂ , benzyl or hydroxybenzyl.) At least one diamine represented by the formula (N) and at least one diamine having no side chain group selected from the diamine group represented by the formulas (I) to (VII) and (XV): Having a side chain group selected from the diamine group represented by formula (VIII) and formula (X) to formula (XIII), and a polyamic acid obtained by reacting a mixture of Polyamic acid obtained by reacting at least one diamine or a mixture of at least one diamine having a side chain group and at least one diamine having no side chain group with tetracarboxylic dianhydride, or a derivative thereof The liquid crystal aligning agent of Claim 1 which is a mixture with these.

(Here, ^{A 3} is a single bond, -O -, - CO -, - COO -, - OCO -, - CONH -, - CH 2 O -, - CF 2 O-, or an alkylene having 1 to 6 carbon atoms And any —CH ₂ — in the alkylene may be replaced by —O—, —CH═CH— or —C≡C—; R ¹ is a group having a steroid skeleton, having 3 to 30 carbon atoms Or an alkyl having 1 to 30 carbon atoms or phenyl having 1 to 30 carbon atoms as a substituent, or a group represented by the formula (IX), —CH ₂ — may be replaced by —O—, —CH═CH— or —C≡C—.

(Wherein A ⁴ and A ⁵ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, alkylene having 1 to 4 carbons, oxyalkylene having 1 to 3 carbons, or C 1-3 alkyleneoxy; ring B and ring C are independently 1,4-phenylene or 1,4-cyclohexylene; R ² and R ³ are independently fluorine or methyl; , f and g are independently 0, 1 or 2; c, d and e is an integer of 0 to 3 independently, their sum is 1 or more; ^{R 4} is 1 to carbon atoms 30 alkyls, alkoxys having 1 to 30 carbons, or alkoxyalkyls having 2 to 30 carbons, and in these alkyls, alkoxys and alkoxyalkyls, any hydrogen may be replaced by fluorine, and any CH ₂ - may be replaced by difluoromethylene).

(In Formula (X) and Formula (XI), R ⁵ is independently hydrogen or methyl, R ⁶ is hydrogen or alkyl or alkenyl having 1 to 20 carbon atoms, and R ⁷ and R ⁸ are each independently C 6-20 alkyl or phenyl, A ⁶ is independently a single bond, —CO— or —CH ₂ —.)

(In Formula (XII) and Formula (XIII), R ⁹ is alkyl having 1 to 30 carbon atoms, and any —CH ₂ — in the alkyl is —O—, —CH═CH—, or —C≡. R ¹⁰ is alkyl having 6 to 22 carbon atoms; R ¹¹ is alkyl having 1 to 22 carbon atoms; A ⁷ is independently —O— or 1 to 6 carbon atoms. A ⁸ is a single bond or alkylene having 1 to 3 carbon atoms; ring T is 1,4-phenylene or 1,4-cyclohexylene; h is 0 or 1)

(In the formulas (I) to (VII) and (XV), X is a linear alkylene having 2 to 12 carbon atoms; Y is independently a single bond, —O—, —CO—, —NH—; , —N (CH ₃ ) —, —CONH—, —NHCO—, —C (CH ₃ ) ₂ —, —C (CF ₃ ) ₂ —, —O— (CH ₂ ) _t —O—, —S— _{, -S-S -, - SO} 2 -, - S- (CH 2) a t -S- or straight chain alkylene of 1 to 12 carbon atoms, t is an integer from 1 to 12; ^{Z 1} and Z ² is hydrogen, but bonded to each other when Y is —NH—, —N (CH ₃ ) —, —CH ₂ —, —C (CH ₃ ) ₂ — or —C (CF ₃ ) ₂ —. It may form a single bond Te; ring D is phenylene or 1,4-diaza-cyclohexylene; R ³³ and R ³⁴ are each independently carbon Be a 1-3 alkyl or phenyl; A ³ is independently an alkylene having 1 to 6 carbon atoms, be phenylene or alkyl-substituted phenylene; m is an integer from 1 to 10; cyclohexane ring or benzene ring Any hydrogen may be replaced by fluorine, methyl, —OH, —COOH, —SO ₃ H, —PO ₃ H ₂ , benzyl or hydroxybenzyl.) The diamine represented by formula (N) is represented by formula (N-1) to formula (N-5), formula (N-7), formula (N-8), formula (N-13), formula (N-15). ) Or a diamine represented by formula (N-16), and the diamine having a side chain group is represented by formula (VIII-2), formula (VIII-4) to formula (VIII-6), or formula (XII-2). Diamines represented by formula (XII-4) or (XII-6) and having no side chain group are formulas (IV-1), (IV-2), and (IV-15). ) To formula (IV-17), formula (V-1) to formula (V-12), formula (V-33), formula (V-35) to formula (V-37), formula (VI-7) The liquid crystal aligning agent of Claim 9 or 10 which is diamine represented by Formula (VII-2) or Formula (XV-1).

(In these formulas, Me means methyl.)

(In these formulas, R ²³ , R ²⁹ and R ³⁰ are each an alkyl having 1 to 30 carbon atoms or an alkoxy having 1 to 30 carbon atoms.)

  The tetracarboxylic dianhydride is an aromatic tetracarboxylic dianhydride or a mixture of an aromatic tetracarboxylic dianhydride and a non-aromatic tetracarboxylic dianhydride. A liquid crystal aligning agent according to item. The aromatic tetracarboxylic dianhydride is at least one selected from the group of compounds represented by formula (1), formula (2), formula (5) to formula (7), formula (11) and formula (14). The liquid crystal aligning agent of Claim 12 which is.

  The liquid crystal aligning agent of Claim 13 whose aromatic tetracarboxylic dianhydride is a compound represented by Formula (1).   The liquid crystal aligning agent of Claim 12 whose tetracarboxylic dianhydride other than aromatic is an alicyclic tetracarboxylic dianhydride and / or an aliphatic tetracarboxylic dianhydride. The aromatic tetracarboxylic dianhydride is at least one selected from the group of compounds represented by formula (1), formula (2), formula (5) to formula (7), formula (11) and formula (14). And non-aromatic tetracarboxylic dianhydrides are represented by formula (19), formula (23), formula (25), formula (35) to formula (39), formula (44) and formula (49). The liquid crystal aligning agent of Claim 12 which is at least 1 chosen from the compound group represented.

  The aromatic tetracarboxylic dianhydride is a compound represented by the formula (1), and the tetracarboxylic dianhydride other than the aromatic is a compound represented by the formula (19). Liquid crystal aligning agent.   The alkenyl-substituted nadiimide compound, a compound having a radically polymerizable unsaturated double bond, an oxazine compound, an oxazoline compound, and an epoxy compound, and further containing at least one compound according to any one of claims 1 to 17. Liquid crystal aligning agent.   The liquid crystal aligning film formed by the coating film of the liquid crystal aligning agent of any one of Claims 1-18 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 A liquid crystal display element comprising: the liquid crystal alignment film according to claim 19, wherein the liquid crystal alignment film is the liquid crystal alignment film.