JP2019040216A - Liquid crystal aligning agent, liquid crystal aligning film and liquid crystal display device - Google Patents

Abstract

A polymer for a liquid crystal aligning agent of a liquid crystal display element having a high response speed is provided. At least one polymer selected from the group consisting of a polyimide precursor having a side chain structure represented by the following formula (I) and a polyimide obtained by imidization thereof. (R1 and R2 are alkyl groups having 1 to 10 carbon atoms, etc .; T1 and T2 are single bonds and the like; S is a single bond and the like are represented by the following structures): Etc .; R3 represents -CH2- etc.) [Selection] None

Description

  The present invention relates to a liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element which can be used for a liquid crystal display element of vertical alignment system manufactured by irradiating ultraviolet light in a state where voltage is applied to liquid crystal molecules.

In a liquid crystal display device of a system (also referred to as vertical alignment (VA) system) in which liquid crystal molecules aligned vertically to the substrate are responded by an electric field (irradiated with ultraviolet light) while applying a voltage to the liquid crystal molecules There is one that includes the step of
In such a vertical alignment type liquid crystal display device, a photopolymerizable compound is previously added to a liquid crystal composition, and a vertical alignment film such as a polyimide type is used to irradiate ultraviolet light while applying a voltage to a liquid crystal cell. There are known techniques for increasing response speed of liquid crystal (PSA (Polymer Sustained Alignment) device, for example, see Patent Document 1 and Non-patent Document 1).

  In such a PSA type device, the tilt direction of liquid crystal molecules in response to an electric field is usually controlled by a protrusion provided on a substrate, a slit provided in a display electrode, etc. The polymer structure in which the inclined direction of the liquid crystal molecules is memorized is formed on the liquid crystal alignment film by adding an organic compound and irradiating the ultraviolet light while applying a voltage to the liquid crystal cell. The response speed of the liquid crystal display element is said to be faster than the method of controlling the tilt direction of the liquid crystal molecules.

On the other hand, in the liquid crystal display element of this PSA system, the solubility of the polymerizable compound added to the liquid crystal is low, and there is a problem that precipitation occurs at low temperature when the addition amount is increased, but it is good when the addition amount of the polymerization compound is reduced. Orientation can not be obtained. In addition, since the unreacted polymerizable compound remaining in the liquid crystal becomes an impurity (contamination) in the liquid crystal, there is also a problem that the reliability of the liquid crystal display element is lowered. In addition, when the UV irradiation treatment required in the PSA method is high, the components in the liquid crystal are decomposed to cause a decrease in reliability.
Furthermore, it has been reported that the response speed of the liquid crystal display element can be increased also by adding a photopolymerizable compound to the liquid crystal alignment film instead of the liquid crystal composition (SC-PVA type liquid crystal display, for example, non-liquid crystal display) Patent Document 2).

JP 2003-307720 A

K. Hanaoka, SID 04 DIGEST, P. 1200-1202 KH Y.-J.Lee, SID 09 DIGEST, P. 666-668

  In recent years, with the improvement of the quality of liquid crystal display elements, it is desired to further accelerate the response speed of liquid crystals to voltage application. For this purpose, it is necessary for the polymerizable compound to react efficiently and to exhibit the ability to fix the alignment by irradiation with ultraviolet light of long wavelength without decomposition of the components in the liquid crystal. Furthermore, it is also necessary that the unreacted polymerizable compound does not remain after irradiation with ultraviolet light, and the reliability of the liquid crystal display device is not adversely affected.

  An object of the present invention is to improve the response speed of a liquid crystal display element obtained by using a step of reacting a polymerizable compound in a liquid crystal and / or in a liquid crystal alignment film without the above-mentioned problems of the prior art. It is providing a liquid crystal aligning agent, a liquid crystal aligning film, and a liquid crystal display element which can be

  As a result of intensive investigations, the present inventors introduced a specific structure that generates radicals upon irradiation with ultraviolet light, to the polymer constituting the liquid crystal alignment agent, and through the use of this liquid crystal alignment agent, Or in the liquid crystal display element obtained by using the step of reacting the polymerizable compound in the liquid crystal alignment film, it is found that the above-mentioned problems can be achieved by enhancing the reactivity of the polymerizable compound, and the present invention has been completed. .

（Ａｒはフェニレン、ナフチレン、及びビフェニレンから選ばれる芳香族炭化水素基を示し、それらには有機基が置換していても良く、水素原子はハロゲン原子に置換していても良い。Ｒ_１、Ｒ_２はそれぞれ独立して炭素原子数１〜１０のアルキル基、アルコキシ基、ベンジル基、又はフェネチル基であり、アルキル基やアルコキシ基の場合、Ｒ_１、Ｒ_２で環を形成していても良い。Ｔ_１、Ｔ_２はそれぞれ独立して、単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−ＮＨ−、−ＣＨ_２Ｏ−、−Ｎ（ＣＨ_３）−、−ＣＯＮ（ＣＨ_３）−、又は−Ｎ（ＣＨ_３）ＣＯ−である。Ｓは、単結合、又は非置換若しくはフッ素原子によって置換されている炭素原子数１〜２０のアルキレン基（但し、アルキレン基の-ＣＨ_２-又はＣＦ_２-は-ＣＨ＝ＣＨ-で置換されていてもよく、また、次のいずれかの基が互いに隣り合わない場合、これらの基に置き換えられていてもよい；−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−ＮＨ−、二価の炭素環若しくは二価の複素環。）である。Ｑは下記の構造を表す。

（Ｒは、水素原子又は炭素原子数１〜４のアルキル基を表し、Ｒ_３は、−ＣＨ_２−、−ＮＲ−、−Ｏ−又は−Ｓ−を表す。）
（２）前記式（Ｉ）で表される側鎖構造を有する重合体が、前記式（Ｉ）で表される側鎖構造を有するポリイミド前駆体及びそれをイミド化して得られるポリイミドからなる群から選ばれる少なくとも１つの重合体である上記（１）に記載の液晶配向剤。 That is, the present invention has the following gist.
(1) A liquid crystal aligning agent comprising a polymer having a side chain structure represented by the following formula (I).

(Ar represents an aromatic hydrocarbon group selected from phenylene, naphthylene and biphenylene, to which an organic group may be substituted, and a hydrogen atom may be substituted to a halogen atom. R ₁ and R ₂ is each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group or a phenethyl group, and in the case of an alkyl group or an alkoxy group, a ring may be formed of R ₁ and R ₂ T ₁ and T ₂ each independently represent a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH _{3 ) -, - CON (CH 3} ) -, or -N _(CH 3) a CO- .S represents a single bond, or an unsubstituted or alkylene group having 1 to 20 carbon atoms which is substituted by fluorine atom ( However, an alkylene group -CH 2 _- or CF 2 _- may be substituted by -CH = CH-, also when any of the groups the following are not adjacent to each other, may be substituted with these groups; -O -, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic ring or a divalent heterocyclic ring)) Q represents the following structure.

(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ represents -CH _2- , -NR-, -O- or -S-.)
(2) A group in which a polymer having a side chain structure represented by the formula (I) is a polyimide precursor having a side chain structure represented by the formula (I) and a polyimide obtained by imidizing the same The liquid crystal aligning agent according to the above (1), which is at least one polymer selected from

（Ｘ^１は、単結合、−（ＣＨ_２）_ａ−（ａは１〜１５の整数である）、−Ｏ−、−ＣＨ_２Ｏ−、−ＣＯＯ−又はＯＣＯ−を表す。Ｘ^２は、単結合又は（ＣＨ_２）_ｂ−（ｂは１〜１５の整数である）を表す。Ｘ^３は、単結合、−（ＣＨ_２）_ｃ−（ｃは１〜１５の整数である）、−Ｏ−、−ＣＨ_２Ｏ−、−ＣＯＯ−又はＯＣＯ−を表す。Ｘ^４はベンゼン環、シクロヘキサン環、及び複素環から選ばれる２価の環状基で表し、これらの環状基の任意の水素原子は、炭素数１〜３のアルキル基、炭素数１〜３のアルコキシル基、炭素数１〜３のフッ素含有アルキル基、炭素数１〜３のフッ素含有アルコキシル基又はフッ素原子で置換されていてもよく、さらに、Ｘ^４は、ステロイド骨格を有する炭素数１７〜５１の有機基から選ばれる２価の有機基であってもよい。Ｘ^５はベンゼン環、シクロヘキサン環及び複素環から選ばれる２価の環状基を表し、これらの環状基上の任意の水素原子は、炭素数１〜３のアルキル基、炭素数１〜３のアルコキシル基、炭素数１〜３のフッ素含有アルキル基、炭素数１〜３のフッ素含有アルコキシル基又はフッ素原子で置換されていてもよい。ｎは０〜４の整数を表す。Ｘ^６は炭素数１〜１８のアルキル基、炭素数１〜１８のフッ素含有アルキル基、炭素数１〜１８のアルコキシル基、又は炭素数１〜１８のフッ素含有アルコキシル基を表す。）

（Ｘ^７は、単結合、−Ｏ−、−ＣＨ_２Ｏ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＮ（ＣＨ_３）−、−Ｎ（ＣＨ_３）ＣＯ−、−ＣＯＯ−又はＯＣＯ−を表す。Ｘ^８は、炭素数８〜２２のアルキル基又は炭素数６〜１８のフッ素含有アルキル基を表す。） (3) The liquid crystal aligning agent as described in said (1) or (2) whose Ar in Formula (I) is a phenyl group and Q is -OR.
(4) The liquid crystal aligning agent according to any one of the above (1) to (3), wherein the polymer further has a side chain which causes liquid crystal to be vertically aligned.
(5) The liquid crystal aligning agent as described in said (4) whose side chain which orientates the said liquid crystal perpendicularly | vertically is at least one chosen from following formula (II-1) and (II-2).

(X ¹ represents a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO— X ² represents Represents a single bond or (CH ₂ ) _b- (b is an integer of 1 to 15.) X ³ represents a single bond,-(CH ₂ ) _c- (c is an integer of 1 to 15),- Represents O-, -CH ₂ O-, -COO- or OCO-, X ⁴ represents a divalent cyclic group selected from a benzene ring, a cyclohexane ring and a heterocyclic ring, and any hydrogen atom of these cyclic groups Is substituted by an alkyl group of 1 to 3 carbon atoms, an alkoxyl group of 1 to 3 carbon atoms, a fluorine-containing alkyl group of 1 to 3 carbon atoms, a fluorine-containing alkoxyl group of 1 to 3 carbon atoms or a fluorine atom well, furthermore, ^{X 4} is selected from an organic group having 17 to 51 carbon atoms having a steroid skeleton Good .X ⁵ even valent organic group represents a divalent cyclic group selected from benzene ring, cyclohexane ring and heterocyclic, any of hydrogen atoms on these cyclic groups, having 1 to 3 carbon atoms It may be substituted by an alkyl group, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. X ⁶ represents an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms. )

(X ⁷ represents a single bond, —O—, —CH ₂ O—, —CONH—, —NHCO—, —CON (CH ₃ ) —, —N (CH ₃ ) CO—, —COO— or OCO— X ⁸ represents an alkyl group having 8 to 22 carbon atoms or a fluorine-containing alkyl group having 6 to 18 carbon atoms.)

（Ｒ^８は、単結合、−ＣＨ_２−、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−ＮＨ−、−ＣＨ_２Ｏ−、−Ｎ（ＣＨ_３）−、−ＣＯＮ（ＣＨ_３）−、又は−Ｎ（ＣＨ_３）ＣＯ−を表す。Ｒ^９は、単結合、フッ素原子で置換されていてもよい炭素数１〜２０のアルキレン基を表し、アルキレン基の−ＣＨ_２−は−ＣＦ_２−又は−ＣＨ＝ＣＨ−で任意に置換されていてもよく、次のいずれかの基が互いに隣り合わない場合、これらの基に置換されていてもよい；−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−ＮＨ−、二価の炭素環若しくは複素環。Ｒ^１０は、下記式から選択される光反応性基を表す。）

（Ｙ_１は−ＣＨ_２−、−Ｏ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨ−、又は−ＣＯ−を表す。Ｙ_２は、炭素数１〜３０のアルキレン基、二価の炭素環若しくは複素環であり、このアルキレン基、二価の炭素環若しくは複素環の１つ又は複数の水素原子は、フッ素原子若しくは有機基で置換されていてもよい。Ｙ_２は、次の基が互いに隣り合わない場合、−ＣＨ_２−がこれらの基に置換されていてもよい；−Ｏ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨ−、−ＮＨＣＯＮＨ−、−ＣＯ−。Ｙ_３は、−ＣＨ_２−、−Ｏ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨ−、−ＣＯ−、又は単結合を表す。Ｙ_４はシンナモイル基を表す。Ｙ_５は単結合、炭素数１〜３０のアルキレン基、二価の炭素環若しくは複素環であり、このアルキレン基、二価の炭素環若しくは複素環の１つ又は複数の水素原子は、フッ素原子若しくは有機基で置換されていてもよい。Ｙ_５は、次の基が互いに隣り合わない場合、−ＣＨ_２−がこれらの基に置換されていてもよい；−Ｏ−、−ＮＨＣＯ−、−ＣＯＮＨ−、−ＣＯＯ−、−ＯＣＯ−、−ＮＨ−、−ＮＨＣＯＮＨ−、−ＣＯ−。Ｙ_６はアクリル基又はメタクリル基である光重合性基を示す。） (6) The liquid crystal aligning agent according to any one of the above (1) to (4), wherein the polymer further has a side chain containing a photoreactive group in the structure.
(7) The liquid crystal aligning agent as described in said (6) in which the side chain which contains the said photoreactive group in a structure is represented by following (III) or Formula (IV).

^{(R 8} is a single _{bond, -CH 2 -, - O -} , - COO -, - OCO -, - NHCO -, - CONH -, - NH -, - CH 2 O -, - N (CH 3) - , -CON _(CH 3) -, or -N _(CH 3) CO- .R ⁹ representing a is a single bond, an alkylene group having a fluorine atom carbon atoms which may be substituted with 1 to 20, an alkylene group In -CH ₂ -may be optionally substituted with -CF ₂ -or -CH = CH-, and any of the following groups may be substituted if not adjacent to each other; -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, divalent carbon ring or heterocyclic ring, and R ¹⁰ represents a photoreactive group selected from the following formulae. )

(Y ₁ represents -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO-. Y ₂ represents 1 to 30 carbon atoms It is an alkylene group, a divalent carbon ring or a heterocyclic ring, and one or more hydrogen atoms of the alkylene group, a divalent carbon ring or a heterocyclic ring may be substituted by a fluorine atom or an organic group. _{In the 2nd} group, -CH _2- may be substituted by these groups when the following groups are not adjacent to each other; -O-, -NHCO-, -CONH-, -COO-, -OCO-,- NH-, -NHCONH-, -CO-, Y ₃ is -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO-, or .Y ₄ representing the bond represents a cinnamoyl group .Y ₅ is a single bond, 1 to 3 carbon atoms And one or more hydrogen atoms of the alkylene group, divalent carbon ring or heterocyclic ring may be substituted with a fluorine atom or an organic group. In Y ₅ , when the following groups are not adjacent to each other, -CH _2- may be substituted by these groups; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-, and Y ₆ represents a photopolymerizable group which is an acrylic group or a methacrylic group.)

式中の記号の定義は、上記式（Ｉ）と同様である。
（９）上記重合体が、さらに下記式（２）で表されるジアミンを含有するジアミン成分と、テトラカルボン酸二無水物成分とを反応させて得られるポリイミド前駆体及びそれをイミド化して得られるポリイミドのうち少なくとも１つの重合体を含有する上記（８）に記載の液晶配向剤。

（Ｘは、上記式［ＩＩ−１］又は式［ＩＩ−２］の構造を示し、ｎは１〜４の整数を示す。）
（１０）上記重合体が、さらに下記式（３）又は（４）で表されるジアミンを含有するジアミン成分と、テトラカルボン酸二無水物成分とを反応させて得られるポリイミド前駆体及びそれをイミド化して得られるポリイミドのうち少なくとも１つの重合体を含有する上記（８）又は（９）に記載の液晶配向剤。

（Ｒ^８、Ｒ^９及びＲ^１０の定義は、上記式（ＩＩＩ）と同じである。）

（Ｙ1、Ｙ２，Ｙ３，Ｙ４，Ｙ５，及びＹ６の定義は、上記式（IV）と同じである。）
（１１）上記（１）で表されるジアミンが、全ジアミン成分の１０モル％〜８０モル％である上記（８）〜（１０）のいずれか１項に記載の液晶配向剤。
（１２）液晶配向剤が、液晶中及び/又は液晶配向膜中に重合性化合物が含有し、電圧を印加しながら紫外線照射により上記重合性化合物が反応させて得られる液晶表示素子用である上記（１）〜（１１）のいずれか1項に記載の液晶配向剤。
（１３）上記（１）〜（１２）のいずれか1項に記載の液晶配向剤から得られる液晶配向膜。
（１４）上記（１３）に記載の液晶配向膜を具備する液晶表示素子。
（１５）液晶表示素子が、電圧を印加しながら紫外線照射により上記重合性化合物が反応させて得られる上記（１４）に記載の液晶表示素子。 (8) A polyimide precursor obtained by reacting a diamine component containing a diamine represented by the following formula (1) with a tetracarboxylic acid dianhydride component and the above-mentioned polymer is obtained by imidizing it The liquid crystal aligning agent according to any one of the above (1) to (7), which contains at least one polymer of polyimides.

The definition of the symbol in a formula is the same as that of said formula (I).
(9) A polyimide precursor obtained by reacting a diamine component containing a diamine represented by the following formula (2) with a tetracarboxylic acid dianhydride component and obtained by imidizing the same: The liquid crystal aligning agent as described in said (8) containing the polymer of at least 1 among polyimides.

(X represents a structure of Formula [II-1] or Formula [II-2] above, and n represents an integer of 1 to 4).
(10) A polyimide precursor obtained by reacting a diamine component containing a diamine represented by the following formula (3) or (4) with a tetracarboxylic acid dianhydride component and the above-mentioned polymer The liquid crystal aligning agent as described in said (8) or (9) which contains at least 1 polymer among the polyimides obtained by imidation.

(The definitions of R ⁸ , R ⁹ and R ¹⁰ are the same as in the above formula (III).)

(The definitions of Y 1, Y 2, Y 3, Y 4, Y 5 and Y 6 are the same as in the above formula (IV).)
(11) The liquid crystal aligning agent as described in any one of said (8)-(10) whose diamine represented by said (1) is 10 mol%-80 mol% of all the diamine components.
(12) The liquid crystal aligning agent is for liquid crystal display devices obtained by containing a polymerizable compound in a liquid crystal and / or in a liquid crystal alignment film and reacting the above-described polymerizable compound by ultraviolet irradiation while applying a voltage. The liquid crystal aligning agent of any one of (1)-(11).
The liquid crystal aligning film obtained from the liquid crystal aligning agent of any one of said (1)-(12).
(14) A liquid crystal display device comprising the liquid crystal alignment film as described in (13) above.
(15) The liquid crystal display element according to (14), wherein the liquid crystal display element is obtained by reacting the polymerizable compound by ultraviolet irradiation while applying a voltage.

式中、Ｒ_１、Ｒ_２、Ｔ_１、Ｔ_２、Ｓ、Ｑ、Ｒの定義は上記式（Ｉ）と同様である。
（１７）下記式（Ｉ）で表されるジアミン。

式中、Ｒ_１、Ｒ_２、Ｔ_１、Ｔ_２、Ｓ、Ｑ、Ｒの定義は上記式（Ｉ）と同様である。
（１８）下記式で表されるジアミン。

(16) A polyimide precursor containing a side chain structure represented by the following formula (I) and at least one polymer of a polyimide obtained by imidizing the same.

In the formulae, the definitions of R ₁ , R ₂ , T ₁ , T ₂ , S, Q and R are the same as in the above formula (I).
(17) Diamine represented by the following formula (I).

In the formulae, the definitions of R ₁ , R ₂ , T ₁ , T ₂ , S, Q and R are the same as in the above formula (I).
(18) Diamine represented by the following formula.

  According to the present invention, it is possible to provide a liquid crystal aligning agent suitable for a liquid crystal display element of vertical alignment system having a high response speed, in particular a PSA type liquid crystal display element. The liquid crystal aligning agent of the present invention can produce a liquid crystal display element with sufficiently improved response speed even when irradiated with ultraviolet light of long wavelength.

The liquid crystal aligning agent of the present invention contains at least one polymer (hereinafter also referred to as a specific polymer) having a structure represented by the above formula (I) in a side chain, and a solvent. The liquid crystal alignment film is a solution for forming a liquid crystal alignment film, and the liquid crystal alignment film is a film for aligning a liquid crystal in a predetermined direction.
As a polymer which has a structure represented by said (I) in a side chain, it is obtained by making the diamine component containing the diamine represented by said Formula (IV), and a tetracarboxylic dianhydride component react. At least one polymer of the polyimide precursor and the polyimide obtained by imidizing it can be used.
In addition, the diamine compound (Hereafter, it is also called a specific diamine.) Represented by the said Formula (IV) is a novel compound of literature unknown.

<Side chain generating radicals by ultraviolet irradiation>
The specific polymer contained in the liquid crystal aligning agent of the present invention has, as a side chain, a site where radicals are generated by ultraviolet irradiation. The site | part from which a radical generate | occur | produces by ultraviolet irradiation can be represented by following formula (I).

  In the above formula (I), since Ar to which a carbonyl is bonded is involved in the absorption wavelength of ultraviolet light, when the wavelength is increased, it is preferable to use a structure having a long conjugation length such as naphthylene or biphenylene. Further, Ar may be substituted by a substituent, and such a substituent is preferably an electron donative organic group such as an alkyl group, a hydroxyl group, an alkoxy group, an amino group and the like.

In the formula (I), when Ar has a structure such as naphthylene or biphenylene, the solubility becomes worse, and the degree of difficulty in synthesis also increases. If the wavelength of ultraviolet light is in the range of 250 nm to 380 nm, sufficient characteristics can be obtained even with a phenyl group, so a phenyl group is most preferable.
R ₁ and R ₂ each independently represent an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group or a phenethyl group, and in the case of an alkyl group or an alkoxy group, R ₁ and R ₂ are rings May be formed.

（Ｒは水、素原子又は炭素原子数１〜４のアルキル基を表し、Ｒ_３は-ＣＨ_２-、−ＮＲ−、−Ｏ−、又は−Ｓ−を表す。）
Ｑがアミノ誘導体の場合、ポリイミドの前駆体であるポリアミック酸の重合の際に、発生するカルボン酸基とアミノ基が塩を形成するなどの不具合が生じる可能性があるため、より好ましくはヒドロキシル基又はアルコキシル基である。 In the formula (I), Q is preferably an electron donating organic group, and the following is preferable.

(R represents water, an atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ represents -CH _2- , -NR-, -O-, or -S-.)
When Q is an amino derivative, it is more preferable to use a hydroxyl group, since problems such as formation of a salt with the generated carboxylic acid group and amino group may occur during polymerization of polyamic acid which is a precursor of polyimide Or an alkoxyl group.

When a polyimide precursor and / or a polyimide is used as a polymer containing a liquid crystal alignment agent and the structure of the above formula (I) is to be introduced into the side chain, the side chain structure of the formula (I) is used It is preferable from the viewpoint of the handleability of the raw materials and the ease of synthesis of the polymer.
Specifically, the site which generates a radical upon irradiation with ultraviolet light in the above formula (I) is preferably the following. In particular, from the viewpoint of the reliability of the liquid crystal display element obtained, (b) or (c) is preferable.

In the formula (I), -T ₁ -S-T ₂ -plays a role of a linking group which links diaminobenzene and a site which generates a radical upon irradiation with ultraviolet light. T ₁ and T ₂ are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N _{(CH 3) -, - CON} (CH 3) -, or -N _(CH 3) a CO-. S is a single bond or an alkylene group having 1 to 20 carbon atoms which may be substituted by a fluorine atom (however, -CH ₂ -or CF _2-of the alkylene group is optionally substituted by -CH = CH- And any of the following groups may not be adjacent to each other, may be substituted by these groups; -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH And is a divalent carbocycle or heterocycle. In particular, T ₂ is most preferably —O— in terms of synthesis difficulty. S is preferably an alkylene group having a carbon number of 2 to 10, more preferably 4 to 8 in view of synthesis difficulty and solubility.

式［ＩＩ−１］におけるＸ^１、Ｘ^２、Ｘ^３、Ｘ^４、Ｘ^５、及びｎは、上記で定義されたとおりである。 <Side chain to align liquid crystal vertically>
It is preferable that the polymer contained in the liquid crystal aligning agent of this invention has the side chain which orientates a liquid crystal perpendicularly | vertically other than the side chain represented by said Formula (I). The side chain which vertically aligns liquid crystal is represented by the following formula [II-1] or formula [II-2].

X ¹ , X ² , X ³ , X ⁴ , X ⁵ and n in the formula [II-1] are as defined above.

Among them, X ¹ is a single bond,-(CH ₂ ) _a- (a is an integer of 1 to 15), -O- or -CH ₂ O from the viewpoint of availability of raw materials and easiness of synthesis. - or COO-, and more preferred are a single _{bond, - (CH 2) a -} (a is an integer of 1 to 10), - O -, - is a _CH 2 O- or COO-. Among them, X ² is preferably a single bond or (CH ₂ ) _b- (b is an integer of 1 to 10). Among them, X ³ is a single bond,-(CH ₂ ) _c- (wherein c is an integer of 1 to 15), -O-, -CH ₂ O- or COO- from the viewpoint of easiness of synthesis. preferably, more preferred are a single _{bond, - (CH 2) c -} (c is an integer of 1 to _{10), - O -, - CH} 2 O- or COO-.

Among them, X ⁴ is preferably a C 17 -C 51 organic group having a benzene ring, a cyclohexane ring or a steroid skeleton from the viewpoint of easiness of synthesis. Among them, X ⁵ is preferably a benzene ring or a cyclohexane ring. Among these, n is preferably 0 to 3 and more preferably 0 to 2 in view of availability of raw materials and easiness of synthesis.
Among them, X ⁶ is preferably an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms or a fluorine-containing alkoxyl group having 1 to 10 carbon atoms. More preferably, it is a C1-C12 alkyl group or a C1-C12 alkoxyl group. Especially preferably, they are a C1-C9 alkyl group or a C1-C9 alkoxyl group.

As a preferable combination of X ¹ , X ² , X ³ , X ⁴ , X ⁵ , X ⁶ and n in the formula [II-1], page 13 of International Publication WO 2011/132751 (released on 2011.10.27) The same combination as (2-1) to (2-629) listed in Tables 6 to 47 on page 34 can be mentioned. In each table of International Publication, ^X 1 to X ⁶ in the present invention is shown as Y1 to Y6, Y1 to ^Y6, shall read X 1 to X ^6.
In addition, in (2-605) to (2-629) listed in each table of the international publication, an organic group having 17 to 51 carbon atoms having a steroid skeleton in the present invention has 12 to 12 carbon atoms having a steroid skeleton. Although indicated as 25 organic groups, an organic group having 12 to 25 carbon atoms having a steroid skeleton is to be read as an organic group having 17 to 51 carbon atoms having a steroid skeleton. Among them, (2-25) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-268) to (2-315) And (2-364) to (2-387), (2-436) to (2-483), or a combination of (2-603) to (2-615) is preferable. Particularly preferred combinations are (2-49) to (2-96), (2-145) to (2-168), (2-217) to (2-240), and (2-603) to (2-). 606), (2-607) to (2-609), (2-611), (2-612) or (2-624).

式［ＩＩ−２］中、Ｘ^７、Ｘ^８は、上記で定義されたとおりである。なかでも、Ｘ^７は、単結合、−Ｏ−、−ＣＨ_２Ｏ−、−ＣＯＮＨ−、−ＣＯＮ（ＣＨ_３）−又はＣＯＯ−が好ましく、より好ましくは、単結合、−Ｏ−、−ＣＯＮＨ−又はＣＯＯ−である。Ｘ^８は、なかでも、炭素数８〜１８のアルキル基が好ましい。

In formula [II-2], X ⁷ and X ⁸ are as defined above. Among them, X ⁷ is preferably a single bond, -O-, -CH ₂ O-, -CONH-, -CON (CH ₃ )-or COO-, more preferably a single bond, -O-, -CONH -Or COO-. Among them, X ⁸ is preferably an alkyl group having 8 to 18 carbon atoms.

As a side chain for vertically aligning liquid crystal, it is preferable to use a structure represented by formula [II-1] from the viewpoint that high and stable vertical alignment of liquid crystal can be obtained.
The ability of a polymer having side chains for vertically aligning liquid crystals to vertically align liquid crystals varies depending on the structure of side chains for vertically aligning liquid crystals, but in general, the side chains for vertically aligning liquid crystals The ability to align liquid crystals vertically increases as the amount of increases, and decreases as it decreases. Moreover, when it has a cyclic structure, the ability to align liquid crystals vertically tends to be higher than that without a cyclic structure.

<Photoreactive side chain>
The polymer contained in the liquid crystal aligning agent of the present invention may have a photoreactive side chain in addition to the side chain represented by the above formula (I). The photoreactive side chain has a functional group (hereinafter, also referred to as a photoreactive group) capable of reacting by irradiation of light such as ultraviolet light (UV) to form a covalent bond.
The photoreactive side chain may be directly bonded to the main chain of the polymer, or may be linked via a linking group. The photoreactive side chain is represented, for example, by the following formula (III).

In formula (III), R ⁸ , R ⁹ , R ¹⁰ are as defined above. Among them, R ⁸ is preferably a single bond, -O-, -COO-, -NHCO or -CONH-. R ⁹ can be formed by a general organic synthetic method, but a single bond or an alkylene group having 1 to 12 carbon atoms is preferable from the viewpoint of easiness of synthesis.

Also, any -CH 2 in the R ⁹ _- a divalent carbocyclic or heterocyclic replacing, specifically, there are exemplified those described below.

R ¹⁰ is preferably a methacryl group, an acryl group or a vinyl group from the viewpoint of photoreactivity.
The amount of the photoreactive side chain is preferably in the range in which the response speed of the liquid crystal can be accelerated by reacting to form a covalent bond by irradiation of ultraviolet light, and in order to further accelerate the response speed of the liquid crystal Preferably, as many as possible, as long as other properties are not affected.

<Polymer Forming Liquid Crystal Alignment Agent>
The polyimide precursor having a specific side chain and the method for producing a polyimide obtained by imidizing the polyimide precursor are not particularly limited. For example, a method of polymerizing a diamine having a specific side chain and tetracarboxylic acid dianhydride, a method of polymerizing a tetracarboxylic acid dianhydride containing a specific side chain and a diamine compound, polymerizing tetracarboxylic acid dianhydride and a diamine After the reaction, a method of modifying a compound containing a specific side chain to a polymer by any reaction may be mentioned. Among them, a method of polymerizing a diamine compound containing a specific side chain and tetracarboxylic acid dianhydride is preferable from the viewpoint of easiness of production.

  The same method as described above is also applied to a polyimide precursor having a side chain and / or a photoreactive side chain for vertically aligning liquid crystal in addition to a specific side chain, and a method for producing a polyimide obtained by imidating the polyimide precursor. It can be mentioned. The preferred method is also a method of polymerizing tetracarboxylic acid dianhydride with a diamine compound containing side chains for vertically aligning liquid crystal and / or a light reactive side chain.

上記式（Ｉ）におけるＡｒ、Ｒ^１、Ｒ^２、Ｔ_１、Ｔ_２、及びＳｎは、上記で定義されたとおりである。 <Specific diamine>
The diamine (hereinafter, also referred to as a specific diamine) used for the production of the above-mentioned polymer forming the liquid crystal aligning agent of the present invention has, as a side chain, a site which is decomposed by ultraviolet irradiation to generate radicals.

Ar, R ¹ , R ² , T ₁ , T ₂ and Sn in the above formula (I) are as defined above.

The diaminobenzene in the formula (I) may have a structure of either o-phenylenediamine, m-phenylenediamine or p-phenylenediamine, but in terms of reactivity with acid dianhydride, m-phenylenediamine, Or p-phenylenediamine is preferred.
The specific amine is most preferably a structure represented by the following formula in terms of easiness of synthesis, high versatility, properties and the like. In the formula, n is an integer of 2 to 8.

<Synthesis of Specific Diamine>
In the present invention, the specific diamine is a dinitro compound through each step, or a mononitro compound having an amino group to which a protective group removable in the reduction step is applied, or a diamine is synthesized and a nitro group is used in a commonly used reduction reaction. Can be obtained by converting into an amino group or deprotecting a protecting group.
There are various methods for synthesizing a diamine precursor. For example, a method of synthesizing a site where radicals are generated by ultraviolet irradiation, introducing a spacer site, and combining with a dinitrobenzene is shown below. In the formula, n is an integer of 2 to 8.

In the case of the above reaction, one having two hydroxyl groups is used, but it can be selectively synthesized by optimizing the type of the base (catalyst) and the preparation ratio.
The base used is not particularly limited, but is preferably an inorganic base such as potassium carbonate, sodium carbonate or cesium carbonate, an organic base such as pyridine, dimethylaminopyridine, trimethylamine, triethylamine or tributylamine.
The method of reducing the dinitro compound which is a diamine precursor is not particularly limited, and usually, palladium carbon, platinum oxide, Raney nickel, platinum carbon, rhodium-alumina, platinum sulfide carbon or the like is used as a catalyst, ethyl acetate, toluene, tetrahydrofuran There is a method of reduction with hydrogen gas, hydrazine, hydrogen chloride or the like in a solvent such as dioxane or alcohol. You may use an autoclave etc. as needed.

On the other hand, in the case where the structure contains an unsaturated bond site, if palladium carbon or platinum carbon is used, the unsaturated bond site may be reduced and it may become a saturated bond. Preferred conditions include reduced iron and tin Preferred are reduction conditions using, as a catalyst, a transition metal such as tin chloride, poisoned palladium carbon or platinum carbon, platinum carbon doped with iron, or the like.
In addition, the diamine of the present invention can be obtained by deprotecting a diaminobenzene derivative protected by a benzyl group or the like in the same manner in the reduction step.
The specific diamine is preferably used in an amount of 10 to 80% by mole, more preferably 20 to 60% by mole, and particularly preferably 30 to 50% by mole of the diamine component used for the synthesis of the polyamic acid.

式［２］中、Ｘは前記式［ＩＩ−１］又は式［ＩＩ−２］で示される構造を表し、ｎは１〜４の整数を表し、特に、１が好ましい。 <Diamine having a side chain for vertically aligning liquid crystal>
It is preferable to use the diamine which has a specific side chain structure as a part of diamine component in the method of introduce | transducing the side chain which orientates a liquid crystal perpendicularly | vertically into a polyimide-type polymer. In particular, it is preferable to use a diamine represented by the following formula [2] (also referred to as a specific side chain type diamine compound).

In Formula [2], X represents a structure represented by Formula [II-1] or Formula [II-2], n represents an integer of 1 to 4, and 1 is particularly preferable.

上記式［２−１］におけるＸ^１、Ｘ^２、Ｘ^３、Ｘ^４、Ｘ^５、及びｎは、上記式［ＩＩ−１］におけるそれぞれで定義されたのと同じであり、また、それぞれの好ましいものも、上記式［ＩＩ−１］におけるそれぞれで定義されたのと同じである。
なお、式［２−１］中、ｍは１〜４の整数である。好ましくは、１の整数である。 As the specific side chain type diamine, it is preferable to use a diamine represented by the following formula [2-1] from the viewpoint that high and stable vertical alignment of liquid crystal can be obtained.

X ¹ , X ² , X ³ , X ⁴ , X ⁵ and n in the above formula [2-1] are the same as defined in each of the above formula [II-1], and Preferred ones are also the same as defined in each of the above Formula [II-1].
In the formula [2-1], m is an integer of 1 to 4. Preferably, it is an integer of 1.

（Ｒ^１は−Ｏ−、−ＯＣＨ_２−、−ＣＨ_２Ｏ−、−ＣＯＯＣＨ_２−又はＣＨ_２ＯＣＯ−を示し、Ｒ^２は炭素数１〜２２の直鎖状若しくは分岐状アルキル基、炭素数１〜２２の直鎖状若しくは分岐状アルコキシル基、炭素数１〜２２の直鎖状若しくは分岐状の、フッ素含有アルキル基又はフッ素含有アルコキシル基である。） Specifically, the specific side chain type diamine includes, for example, structures represented by the following Formula [2a-1] to Formula [2a-31].

(R ¹ represents -O-, -OCH _2- , -CH ₂ O-, -COOCH ₂ -or CH ₂ OCO-, R ² represents a linear or branched alkyl group having 1 to 22 carbon atoms, carbon It is a linear or branched alkoxyl group of the number 1-22, a linear or branched C1-C22 linear or branched, fluorine-containing alkyl group or fluorine-containing alkoxyl group.)

（Ｒ^３は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−又はＣＨ_２−を示し、Ｒ^４は炭素数１〜２２の直鎖状若しくは分岐状アルキル基、炭素数１〜２２の直鎖状若しくは分岐状アルコキシル基、炭素数１〜２２の直鎖状若しくは分岐状の、フッ素含有アルキル基又はフッ素含有アルコキシル基である）。

(R ³ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH _2- , -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ -or CH _2- , R ⁴ is a linear or branched alkyl group having 1 to 22 carbon atoms, a linear or branched alkoxyl group having 1 to 22 carbon atoms, a linear or branched alkyl group having 1 to 22 carbon atoms, Or a fluorine-containing alkoxyl group).

（Ｒ^５は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、−ＣＨ_２−、−Ｏ−又はＮＨ−を示し、Ｒ^６はフッ素基、シアノ基、トリフルオロメタン基、ニトロ基、アゾ基、ホルミル基、アセチル基、アセトキシ基又は水酸基である）。

(R ⁵ is -COO-, -OCO-, -CONH-, -NHCO-, -COOCH _2- , -CH ₂ OCO-, -CH ₂ O-, -OCH _2- , -CH _2- , -O R ⁶ represents a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, an acetyl group, an acetoxy group or a hydroxyl group).

（Ｒ^７は炭素数３〜１２の直鎖状又は分岐状アルキル基であり、１,４-シクロヘキシレンのシス−トランス異性は、それぞれトランス異性体である）。

(R ⁷ is a linear or branched alkyl group having 3 to 12 carbon atoms, and cis-trans isomerism of 1,4-cyclohexylene is trans isomer, respectively).

（Ｒ^８は炭素数３〜１２の直鎖状又は分岐状アルキル基であり、１,４-シクロヘキシレンのシス−トランス異性は、それぞれトランス異性体である）。

(R ⁸ is a linear or branched alkyl group having 3 to 12 carbon atoms, and cis-trans isomerism of 1,4-cyclohexylene is trans isomer, respectively).

（Ａ_４はフッ素原子で置換されていてもよい炭素数３〜２０の直鎖状又は分岐状アルキル基であり、Ａ_３は１，４−シクロへキシレン基又は１，４−フェニレン基であり、Ａ_２は酸素原子又はＣＯＯ−＊（ただし、「＊」を付した結合手がＡ_３と結合する）であり、Ａ_１は酸素原子又はＣＯＯ−＊（ただし、「＊」を付した結合手が（ＣＨ_２）ａ_２）と結合する）である。また、ａ_１は０又は１の整数であり、ａ_２は２〜１０の整数であり、ａ_３は０又は１の整数である）。

(A ₄ is a linear or branched alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, and A ₃ is a 1,4-cyclohexylene group or a 1,4-phenylene group. , A ₂ is an oxygen atom or COO- * (wherein a bond with "*" is bonded to A ₃ ), A ₁ is an oxygen atom or COO- * (with "*" bond) The hand is coupled to (CH ₂ ) a ₂ )). Also, _{a 1} is an integer of 0 or 1, _{a 2} is an integer of 2 to 10, _{a 3} is an integer of 0 or 1).

  Among the above formulas [2a-1] to [2a-31], particularly preferable ones are the formulas [2a-1] to [2a-6], [2a-9] to [2a-13] or [Formula 2] 2a-22] to the formula [2a-31].

（Ａ^１は、炭素数１〜２２のアルキル基又はフッ素含有アルキル基を示す）。 Moreover, as a diamine which has a specific side chain structure shown by said Formula [II-2], the diamine shown by following formula [2b-1]-[2b-10] is mentioned.

(A ¹ represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group).

In the above formulas [2b-5] to [2b-10], A ¹ is -COO-, -OCO-, -CONH-, -NHCO-, -CH _2- , -O-, -CO- or NH- And A ² represents a linear or branched alkyl group having 1 to 22 carbon atoms or a linear or branched fluorine-containing alkyl group having 1 to 22 carbon atoms.
The above diamines may be used alone or in combination of two or more, according to the properties such as liquid crystal alignment property, pretilt angle, voltage holding property, accumulated charge, etc. when forming a liquid crystal alignment film.

It is preferable to use 5 to 50 mol% of the diamine component used in the synthesis of the polyamic acid, more preferably 10 to 40 mol% of the diamine component, and particularly preferably the diamine having a side chain for vertically orienting the liquid crystal. Is 15 to 30 mol%.
The use of a diamine having a side chain that vertically aligns the liquid crystal is particularly excellent in terms of the improvement of the response speed and the ability to fix the alignment of the liquid crystal.

（式（３）中のＲ^８、Ｒ^９及びＲ^１０の定義は、上記式（ＩＩＩ）と同じである。） <Diamine containing photoreactive side chain>
Examples of the diamine having a photoreactive side chain include diamines having a side chain represented by Formula (3), and specifically, diamines represented by the following General Formula (3) But not limited thereto.

(The definition of R ⁸ , R ⁹ and R ^{10 in} the formula (3) is the same as the above formula (III).)

The bonding position of the two amino groups (-NH ₂ ) in the formula (3) is not limited. Specifically, with respect to the linking group of the side chain, the 2, 3 positions, 2, 4 positions, 2, 5 positions, 2, 6 positions, 3, 4 positions, 3, 4 positions on the benzene ring There are 5 positions. Among them, from the viewpoint of reactivity when synthesizing a polyamic acid, the positions of 2, 4, 2, 5, or 3, 5 are preferable. The positions of 2, 4 or 3, 5 are more preferable in consideration of the ease of synthesis of the diamine.

（Ｘ^９、Ｘ^１０は、それぞれ独立に、単結合、−Ｏ−、−ＣＯＯ−、−ＮＨＣＯ−、又は−ＮＨ−である結合基、Ｙはフッ素原子で置換されていてもよい炭素数１〜２０のアルキレン基を表す。） Specific examples of the diamine having a photoreactive side chain include the following.

(X ⁹ and X ¹⁰ each independently represent a single bond, a bonding group which is -O-, -COO-, -NHCO-, or -NH-, and Y is a carbon atom which may be substituted with a fluorine atom And an alkylene group of -20.)

Moreover, as diamine which has a photoreactive side chain, the diamine which has the group which raise | generates the photodimerization reaction represented by a following formula, and the group which raise | generates a photopolymerization reaction in a side chain is also mentioned.

In the above formulae, Y ₁ represents -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO-. Y ₂ is an alkylene group having 1 to 30 carbon atoms, a divalent carbon ring or a heterocyclic ring, and one or more hydrogen atoms of this alkylene group, a divalent carbon ring or a heterocyclic ring are a fluorine atom or an organic It may be substituted by a group. In Y ₂ , when the following groups are not adjacent to each other, -CH _2- may be substituted by these groups; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y _{3 is, -CH 2 -, - O -} , - CONH -, - NHCO -, - COO -, - OCO -, - NH -, - CO-, or a single bond. Y ₄ represents a cinnamoyl group. Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbon ring or a heterocyclic ring, and one or more hydrogen atoms of this alkylene group, a divalent carbon ring or a heterocyclic ring are fluorine atoms Or may be substituted by an organic group. In Y ₅ , when the following groups are not adjacent to each other, -CH _2- may be substituted by these groups; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y ₆ represents a photopolymerizable group which is an acrylic group or a methacrylic group.

The diamine having the photoreactive side chain is selected according to the liquid crystal alignment property, the pretilt angle, the voltage holding property, the characteristics such as the accumulated charge when the liquid crystal alignment film is formed, and the response speed of the liquid crystal when the liquid crystal display element is formed. It is possible to use one or two or more kinds in combination.
The diamine having a photoreactive side chain is preferably used in an amount of 10 to 70% by mole, more preferably 20 to 60% by mole, and particularly preferably 30 to 50% by mole of the diamine component used in the synthesis of the polyamic acid. It is.

<Other diamines>
In addition, when manufacturing a polyimide precursor and / or a polyimide, as long as the effect of this invention is not impaired, other diamine other than the above-described diamine can be used together as a diamine component. Specifically, for example, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl- m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2, 4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl 3,3'-Dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobiphenyl Nil, 3,3'-difluoro-4,4'-biphenyl, 3,3'-trifluoromethyl-4,4'-diaminobiphenyl, 3,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2 2,2′-diaminobiphenyl, 2,3′-diaminobiphenyl, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 2,2′-diaminodiphenylmethane, 2,3 '-Diaminodiphenylmethane, 4,4'-diaminodiphenylether, 3,3'-diaminodiphenylether, 3,4'-diaminodiphenylether, 2,2'-diaminodiphenylether, 2,3'-diaminodiphenylether, 4,4'- Sulfonyldianiline, 3,3'-sulfonyldianiline, bis (4-aminophenyl) ring Orchid, bis (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4'-thiodianiline, 3,3'-thiodianiline, 4,4 '-Diaminodiphenylamine, 3,3'-diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl (4,4'-diaminodiphenyl) amine N-methyl (3,3'-diaminodiphenyl) amine, N-methyl (3,4'-diaminodiphenyl) amine, N-methyl (2,2'-diaminodiphenyl) amine, N-methyl (2,3 '-Diaminodiphenyl) amine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4' Diaminobenzophenone, 1,4-diaminonaphthalene, 2,2'-diaminobenzophenone, 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8 -Diaminonaphthalene, 2,5-diaminonaphthalene, 2,6 diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-aminophenyl) ethane, 1,2-bis ( 3-aminophenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (4-aminophenyl) butane, 1,4- Bis (3-aminophenyl) butane, bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4- Aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis ( 4-Aminobenzyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 ′-[1,4-phenylenebis (methylene)] dianiline, 4,4 ′-[1,3-phenylenebis (Methylene)] dianiline, 3,4 '-[1,4-phenylenebis (methylene)] dianiline, 3,4'-[1,3-phenylenebis (methylene)] dianiline, 3,3 '-[1,1 4-phenylenebis (methylene)] dianiline, 3,3 ′-[1,3-phenylenebis (methylene)] dianiline, 1,4-phenylenebis [(4-aminophenyl) methanone], 1, -Phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [(3-aminophenyl) methanone], 1,4-phenylene Bis (4-aminobenzoate), 1,4-phenylene bis (3-aminobenzoate), 1,3-phenylene bis (4-aminobenzoate), 1,3-phenylene bis (3-aminobenzoate), bis (4) -Aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N, N '-(1,4-phenylene) bis (4) -Aminobenzamido), N, N '-(1,3-phenylene) bis (4-aminobenzamido), N, N '-(1,4-phenylene) bis (3-aminobenzamido), N, N'-(1,3-phenylene) bis (3-aminobenzamido), N, N'-bis (4-aminophenyl) Terephthalamide, N, N′-bis (3-aminophenyl) terephthalamide, N, N′-bis (4-aminophenyl) isophthalamide, N, N′-bis (3-aminophenyl) isophthalamide, 9,9 10-bis (4-aminophenyl) anthracene, 4,4′-bis (4-aminophenoxy) diphenyl sulfone, 2,2′-bis [4- (4-aminophenoxy) phenyl] propane, 2,2′- Bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2′-bis (4-aminophenyl) hexafluoropropane, 2,2′-bis (3-aminophen ) Hexafluoropropane, 2,2'-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2'-bis (4-aminophenyl) propane, 2,2'-bis (3-amino) Phenyl) propane, 2,2'-bis (3-amino-4-methylphenyl) propane, 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, 1,3-bis (4-aminophenoxy) propane 1,3-bis (3-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) ) Pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,6-bis (3-aminophenoxy) hexane, 1, Bis (4-aminophenoxy) heptane, 1,7- (3-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,8-bis (3-aminophenoxy) octane, 1, 9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10- (4-aminophenoxy) decane, 1,10- (3-aminophenoxy) decane, 1,1 Aromatic diamines such as 11- (4-aminophenoxy) undecane, 1,11- (3-aminophenoxy) undecane, 1,12- (4-aminophenoxy) dodecane, 1,12- (3-aminophenoxy) dodecane And alicyclic diamines such as bis (4-aminocyclohexyl) methane and bis (4-amino-3-methylcyclohexyl) methane; Diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diamino Aliphatic diamines such as decane, 1,11-diaminoundecane, 1,12-diaminododecane and the like.

  The above-mentioned other diamines can be used alone or in combination of two or more, depending on the properties such as liquid crystal alignment property, pretilt angle, voltage holding property, accumulated charge and the like when forming a liquid crystal alignment film.

<Tetracarboxylic acid dianhydride>
The tetracarboxylic acid dianhydride component to be reacted with the above diamine component is not particularly limited. Specifically, pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2, 3,6,7-anthracenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3', 4-biphenyltetra Carboxylic acid, bis (3,4-dicarboxyphenyl) ether, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxy) Phenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (3,4-dicarboxyphenyl) Lopane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3,4 -Dicarboxyphenyl) pyridine, 3,3 ', 4,4'-diphenyl sulfone tetracarboxylic acid, 3,4,9,10-perylene tetracarboxylic acid, 1,3-diphenyl-1,2,3,4- Cyclobutane tetracarboxylic acid, oxydiphthalic tetracarboxylic acid, 1,2,3,4-cyclobutane tetracarboxylic acid, 1,2,3,4-cyclopentane tetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid Acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobu Tetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid, 1,2,3,4-cycloheptane tetracarboxylic acid, 2,3,4,5-tetrahydrofuran tetracarboxylic acid 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid, bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid, bicyclo [4,3,0] nonane-2,4,7,9-tetracarboxylic acid, bicyclo [4,4,0 Decane-2,4,7,9-tetracarboxylic acid, bicyclo [4,4,0] decane-2,4,8,10-tetracarboxylic acid, tricyclo [6.3.0.0 <2,6 >] Undecane 3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetra Hydride naphthalene-1,2-dicarboxylic acid, bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuryl) -3 -Methyl-3-cyclohexane-1,2-dicarboxylic acid, tetracyclo [6,2,1,1,0,2,7] dodeca-4,5,9,10-tetracarboxylic acid, 3,5, 6-tricarboxy norbornane-2: 3,5: 6 dicarboxylic acid, 1,2,4,5- cyclohexane tetracarboxylic acid etc. are mentioned. Of course, one or more types of tetracarboxylic acid dianhydrides may be used in combination depending on the properties such as liquid crystal alignment property, voltage holding property, and accumulated charge in forming a liquid crystal alignment film.

<Polymerizable compound>
The liquid crystal aligning agent of the present invention may optionally contain a polymerizable compound having a group capable of photopolymerization or photocrosslinking at two or more ends. Such a polymerizable compound is a compound having two or more ends having a group capable of photopolymerization or photocrosslinking. Here, the polymerizable compound which has a group which photopolymerizes is a compound which has a functional group which causes superposition | polymerization by irradiating light. Further, the compound having a photocrosslinkable group is at least one selected from a polymer of a polymerizable compound, a polyimide precursor, and a polyimide obtained by imidizing this polyimide precursor by irradiating light. And a compound having a functional group capable of reacting with the polymer of and crosslinking with these. In addition, the compound which has group which photocrosslinks also reacts with compounds which have group which photocrosslinks.

  By using the liquid crystal aligning agent of the present invention containing the above-mentioned polymerizable compound in a liquid crystal display element of a vertical alignment system such as a SC-PVA type liquid crystal display, side chains for vertically aligning this liquid crystal and photoreactivity The response speed can be significantly improved as compared with the case of using a polymer having a side chain or this polymerizable compound alone, and the response speed can be sufficiently improved even with a small amount of the polymerizable compound added. Can.

（Ｒ^１２は、水素原子、又は炭素数１〜４のアルキル基を表す。Ｚ^１は、炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシル基によって置換されていてもよい二価の芳香環若しくは複素環を表す。Ｚ^２は炭素数１〜１２のアルキル基又は炭素数１〜１２のアルコキシル基によって置換されていてもよい一価の芳香環若しくは複素環を表す。） As a group which photopolymerizes or photocrosslinks, the monovalent group represented by following formula (IV) is mentioned.

(R ¹² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Z ¹ is a bivalent which may be substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms And Z ² represents a monovalent aromatic ring or heterocyclic ring which may be substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms.

Specific examples of the polymerizable compound include a compound having a group which is photopolymerized at each of two ends represented by the following formula (V), an end having a photopolymerizing group represented by the following formula (VI), and a light The compound which has a terminal which has a group which bridge | crosslinks, and the compound which has a group which photocrosslinks to each of two terminals represented by following formula (VII) are mentioned.
In Formula ^{(V) ~ (VII),} R 12, Z 1 and ^{Z 2} are the same as ^R 12, ^{Z 1} and ^{Z 2} in the formula (IV), ^{Q 1} is a divalent organic group is there. Q ¹ represents a phenylene group _{(-C 6 H} 4 -), biphenylene group _{(-C 6 H 4 -C 6 H} 4 -), cyclohexylene _{(-C 6 H 10} -) having a cyclic structure, such as Is preferred. This is because the interaction with the liquid crystal tends to be large.

Specific examples of the polymerizable compound represented by the formula (V) include polymerizable compounds represented by the following formula (4). In the following formula (4), V and W are each represented by a single bond or -R ¹ O-, and R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms, preferably- represented by ^{R 1} O-, R ¹ is a linear or branched alkylene group having 2 to 6 carbon atoms. V and W may be the same or different, but if they are the same, synthesis is easy.

  In addition, even if it is a polymerizable compound which does not have an α-methylene-γ-butyrolactone group but an acrylate group or a methacrylate group as a group to be photopolymerized or photocrosslinked, this acrylate group or methacrylate group is a spacer such as an oxyalkylene group. The polymerizable compound having a structure in which it is bonded to a phenylene group via the group can improve the response speed particularly significantly in the same manner as the polymerizable compound having an α-methylene-γ-butyrolactone group at both ends. . In addition, the polymerizable compound having a structure in which an acrylate group or a methacrylate group is bonded to a phenylene group via a spacer such as an oxyalkylene group improves the stability to heat, and a high temperature, for example, a baking temperature of 200 ° C. or more Can withstand enough.

（式中、Ｒ’は一価の有機基を表す。） The manufacturing method of the said polymeric compound is not specifically limited, For example, it can manufacture according to the following synthesis example. For example, as the polymerizable compound represented by the above-mentioned formula (4), a method which Taraga et al. Represented by the following reaction formula propose by P. Thus, it can be synthesized by reacting 2- (bromomethyl) propenoic acid with aldehyde or ketone using SnCl ₂ . Amberlyst 15 is a strongly acidic ion exchange resin manufactured by Rohm and Haas.

(Wherein R ′ represents a monovalent organic group)

In addition, 2- (bromomethyl) acrylic acid is proposed by Ramalana et al., Represented by the following reaction formula, by K. Ramarajan, K. Kamalingam, DJO 'Donnell and KDBerlin, Organic Synthesis, vol. 61, 56-59 (1983) Can be synthesized by

As a specific synthesis example, when synthesizing a polymerizable compound represented by the above formula (1) in which V is -R ¹ O-, W is -OR ² -and R ¹ and R ² are the same, There are two methods shown in the reaction formula.

Also, when synthesizing the polymerizable compound R ¹ and R ² are represented by different above formula (4) include a method represented by the following reaction formula.

When synthesize | combining the polymeric compound whose V and W are single bonds in said Formula (4), the method shown by following Reaction Formula is mentioned.

<Synthesis of polyamic acid>
In order to obtain a polyamic acid by the reaction of a diamine component and tetracarboxylic acid dianhydride, known synthetic methods can be used. Generally, it is a method of reacting a diamine component and a tetracarboxylic acid dianhydride component in an organic solvent. The reaction of the diamine component with the tetracarboxylic acid dianhydride proceeds in an organic solvent relatively easily and is advantageous in that no by-products are generated.

  The organic solvent used for the above reaction is not particularly limited as long as the generated polyamic acid can be dissolved. Furthermore, even if it is an organic solvent in which a polyamic acid does not melt | dissolve, you may use it, mixing with the said solvent in the range which the produced | generated polyamic acid does not precipitate. Since water in the organic solvent inhibits the polymerization reaction and causes hydrolysis of the formed polyamic acid, it is preferable to use the organic solvent which has been dehydrated and dried.

  Examples of the organic solvent used in the above reaction include N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N-methylformamide, N-methyl-2-pyrrolidone, N-ethyl-2 -Pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide, N-methylcaprolactam, dimethylsulfoxide, tetramethylurea, pyridine, dimethylsulfone, hexamethyl Sulfoxide, γ-butyrolactone, isopropyl alcohol, methoxymethyl pentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, Lucerosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether , Propylene glycol monobutyl ether, propylene glycol tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether , Dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl -3-Methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexylene, propyl ether , Dihexyl ether, dioxane, n-hexane, n-pentane, n-octa , Diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate Methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4- 4- Methyl-2-pentanone, 2-ethyl-1-hexanol and the like can be mentioned. These organic solvents may be used alone or in combination.

  The method of reacting the diamine component and the tetracarboxylic acid dianhydride component in an organic solvent is to stir a solution in which the diamine component is dispersed or dissolved in the organic solvent, and the tetracarboxylic acid dianhydride component as it is or as an organic solvent The method of adding or dispersing in a solvent, or the method of adding a diamine component to a solution in which the tetracarboxylic acid dianhydride component is dispersed or dissolved in an organic solvent, or alternating the tetracarboxylic acid dianhydride component and the diamine component Any method such as adding to In addition, when the diamine component or the tetracarboxylic acid dianhydride component is composed of a plurality of types of compounds, it may be reacted in a mixed state in advance, or may be reacted separately one after another, and further, it is a low molecular weight individually reacted. The body may be mixed and reacted to form a high molecular weight product.

The temperature at the time of reacting the diamine component and the tetracarboxylic acid dianhydride component is, for example, in the range of -20 ° C to 150 ° C, preferably -5 ° C to 100 ° C. Moreover, 1-50 mass% of the density | concentration of the sum total of a diamine component and a tetracarboxylic dianhydride component is preferable with respect to a reaction liquid, for example, 5-30 mass% of reaction is more preferable.
The ratio of the total number of moles of tetracarboxylic acid dianhydride component to the total number of moles of diamine components in the above polymerization reaction can be selected according to the molecular weight of the polyamic acid to be obtained. As in the case of a conventional polycondensation reaction, the molecular weight of the polyamic acid produced increases as the molar ratio approaches 1.0, and is preferably 0.8 to 1.2 if it indicates a preferred range.

The method for synthesizing the polyamic acid used in the present invention is not limited to the above-described method, and instead of the above-mentioned tetracarboxylic acid dianhydride, a tetracarboxylic acid having a corresponding structure is used similarly to the general polyamic acid synthesis method. Acids or tetracarboxylic acid derivatives such as tetracarboxylic acid dihalides can also be used for reaction according to known methods to obtain the corresponding polyamic acids.
As a method of imidating the above-mentioned polyamic acid and setting it as a polyimide, the thermal imidization which heats the solution of polyamic acid as it is, the catalyst imidization which adds a catalyst to the solution of polyamic acid are mentioned. The imidation ratio from polyamic acid to polyimide is not necessarily 100%.

The temperature for thermally imidizing polyamic acid in a solution is 100 ° C. to 400 ° C., preferably 120 ° C. to 250 ° C., and it is preferable to carry out while removing water generated by the imidization reaction out of the system.
Catalytic imidization of polyamic acid can be carried out by adding a basic catalyst and an acid anhydride to a solution of polyamic acid and stirring at -20 to 250 ° C, preferably 0 to 180 ° C. The amount of the basic catalyst is 0.5 to 30 moles, preferably 2 to 20 moles, of the amic acid group, and the amount of the acid anhydride is 1 to 50 moles, preferably 3 to 30 moles of the amic acid group. It is a double. The basic catalyst may, for example, be pyridine, triethylamine, trimethylamine, tributylamine or trioctylamine. Among them, pyridine is preferable because it has an appropriate basicity to allow the reaction to proceed. As the acid anhydride, acetic anhydride, trimellitic anhydride, pyromellitic anhydride and the like can be mentioned, and among them, acetic anhydride is preferable, because purification after completion of the reaction becomes easy. The imidation ratio by catalytic imidation can be controlled by adjusting the amount of catalyst, reaction temperature and reaction time.

  In addition, the polyamic acid ester may be a reaction of a tetracarboxylic acid diester dichloride with a diamine similar to the synthesis of the polyamic acid, a tetracarboxylic acid diester and a diamine similar to the synthesis of the polyamic acid, a suitable condensing agent, It can be produced by reacting in the presence of a base or the like. Alternatively, it can be obtained by previously synthesizing a polyamic acid by the above method and esterifying a carboxylic acid in the amic acid using a polymer reaction. Specifically, for example, tetracarboxylic acid diester dichloride and diamine in the presence of a base and an organic solvent at -20 ° C to 150 ° C, preferably at 0 ° C to 50 ° C, for 30 minutes to 24 hours, preferably 1 hour The polyamic acid ester can be synthesized by reacting for 4 hours. And a polyimide can be obtained also by heating a polyamic acid ester at high temperature, prompting dealcoholization and closing the ring.

  In the case of recovering the produced polyimide precursor or polyimide such as polyamic acid or polyamic acid ester from the reaction solution, the reaction solution may be poured into a poor solvent and precipitated. As a poor solvent used for precipitation, methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, water and the like can be mentioned. The polymer precipitated by being introduced into the poor solvent may be recovered by filtration and then dried by heating at normal temperature or under normal pressure or reduced pressure. Further, by repeating the operation of re-dissolving the recovered polymer in an organic solvent and recovering the re-precipitation 2 to 10 times, impurities in the polymer can be reduced. As a poor solvent in this case, for example, alcohols, ketones, hydrocarbons and the like can be mentioned, and it is preferable to use three or more poor solvents selected from these, because the efficiency of purification is further enhanced.

<Liquid crystal alignment agent>
The agent of the present invention contains at least one polymer having a structure represented by the above formula (1) in the side chain, and the content of such a polymer is preferably 1 to 20% by mass, more preferably 3 to 3 It is 15% by mass, particularly preferably 3 to 10% by mass. Moreover, when it contains the polymeric compound which each has the group which photopolymerizes or photocrosslinks in two or more terminal, the content is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the above-mentioned polymer, Preferably it is 5-30 mass parts.

Moreover, the liquid crystal aligning agent of this invention may contain other polymers other than the said polymer. At that time, the content of such other polymer in all components of the polymer is preferably 0.5 to 80% by mass, and more preferably 20 to 50% by mass.
The molecular weight of the polymer possessed by the liquid crystal aligning agent is determined by GPC (Gel Permeation Chromatography) in consideration of the strength of the liquid crystal aligning film obtained by applying the liquid crystal aligning agent, the workability at the time of forming a coating, and the uniformity of the coating. 5,000-1,000,000 are preferable at the weight average molecular weight measured by method), and 10,000-150,000 are more preferable.

  There is no particular limitation on the solvent contained in the liquid crystal aligning agent, and a polymer having a structure represented by the above formula (1) in a side chain, and, if necessary, a photopolymerization in two or more ends Or what is necessary is just to be able to melt | dissolve or disperse | distribute components, such as a polymeric compound which has the group to photocrosslink, respectively. For example, organic solvents as exemplified in the synthesis of polyamic acids described above can be mentioned. Among them, N-methyl-2-pyrrolidone, γ-butyrolactone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and 3-methoxy-N, N-dimethylpropanamide have solubility points It is preferable from Of course, two or more mixed solvents may be used.

  Moreover, it is preferable to mix and use the solvent which improves the uniformity and smoothness of a coating film with the solvent with high solubility of the component of a liquid crystal aligning agent. Such solvents include, for example, isopropyl alcohol, methoxymethyl pentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, Ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol monomethyl ether , Diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, Dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene , Amyl acetate , Butyl butyrate, butyl ether, diisobutyl ketone, methyl cyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, acetic acid n -Butyl, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropion Acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanoate , Propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol And lactic acid methyl ester, lactic acid ethyl ester, lactic acid n-propyl ester, lactic acid n-butyl ester, lactic acid isoamyl ester, 2-ethyl-1-hexanol and the like. A plurality of these solvents may be mixed. 5-80 mass% of the whole solvent contained in a liquid crystal aligning agent is preferable, and, as for these solvents, 20-60 mass% is more preferable.

The liquid crystal aligning agent may contain components other than the above. As the example, the compound which improves the film thickness uniformity and surface smoothness at the time of apply | coating a liquid crystal aligning agent, the compound which improves the adhesiveness of a liquid crystal aligning film and a board | substrate, etc. are mentioned.
As a compound which improves the uniformity of a film thickness, and surface smoothness, a fluorochemical surfactant, silicone type surfactant, nonion type surfactant etc. are mentioned. More specifically, for example, F-top EF301, EF303, EF352 (manufactured by Tochem Products), Megafuck F171, F173, R-30 (manufactured by Dainippon Ink and Chemicals, Inc.), Florard FC430, FC431 (manufactured by Sumitomo 3M) Asahi Guard AG710, Surfron S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.) and the like. The proportion of these surfactants used is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 parts by mass, per 100 parts by mass of the total amount of polymers contained in the liquid crystal aligning agent. .

  As a specific example of a compound which improves the adhesiveness of a liquid crystal aligning film and a board | substrate, a functional silane containing compound, an epoxy group containing compound, etc. are mentioned. For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxy Carbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-to Ethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyl tri Methoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-amino Propyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether , Polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl ether, 1,3,5,6-tetra Glycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N' And N'-tetraglycidyl-4, 4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N-diglycidyl) aminopropyltrimethoxysilane and the like. .

In order to further increase the film strength of the liquid crystal alignment film, a phenol compound such as 2,2'-bis (4-hydroxy-3,5-dihydroxymethylphenyl) propane or tetra (methoxymethyl) bisphenol may be added. 0.1-30 mass parts is preferable with respect to 100 mass parts of total amounts of the polymer contained in a liquid crystal aligning agent, and, as for these compounds, 1-20 mass parts are more preferable.
Furthermore, to the liquid crystal aligning agent, in addition to the above, a dielectric or a conductive substance for the purpose of changing electric properties such as dielectric constant or conductivity of the liquid crystal alignment film may be added as long as the effects of the present invention are not impaired. You may

  By applying this liquid crystal aligning agent on a substrate and baking it, it is possible to form a liquid crystal alignment film for aligning liquid crystals vertically. By using the liquid crystal aligning agent of the present invention, the response speed of the liquid crystal display device using the liquid crystal alignment film obtained can be made faster. In addition, a polymerizable compound having a photopolymerization or photocrosslinkable group at two or more ends, which may be contained in the liquid crystal aligning agent of the present invention, is not contained in the liquid crystal aligning agent, or a liquid crystal aligning agent At the same time, by incorporating it in the liquid crystal, it is possible to increase the photosensitivity even in the so-called PSA mode, and to provide a tilt angle even with a small amount of ultraviolet radiation.

  For example, after apply | coating the liquid crystal aligning agent of this invention to a board | substrate, it can dry as needed, and can also use the cured film obtained by baking as a liquid crystal aligning film as it is. In addition, this cured film is rubbed, polarized light or irradiated with light of specific wavelength, etc., treated with ion beam, etc., a state in which a voltage is applied to the liquid crystal display element after liquid crystal filling as an alignment film for PSA. It is also possible to irradiate UV. In particular, it is useful to use as an alignment film for PSA.

  At this time, the substrate to be used is not particularly limited as long as it is a substrate having high transparency, and a glass plate, polycarbonate, poly (meth) acrylate, polyether sulfone, polyarylate, polyurethane, polysulfone, polyether, polyether ketone A plastic substrate such as trimethylpentene, polyolefin, polyethylene terephthalate, (meth) acrylonitrile, triacetyl cellulose, diacetyl cellulose, acetate butyrate cellulose, or the like can be used. Moreover, it is preferable from the viewpoint of process simplification to use a substrate on which an ITO electrode or the like for driving liquid crystal is formed. Further, in the reflection type liquid crystal display element, if it is only the substrate on one side, an opaque material such as a silicon wafer can be used, and in this case, a material that reflects light such as aluminum can also be used.

The coating method of the liquid crystal aligning agent is not particularly limited, and printing methods such as screen printing, offset printing, flexo printing, an inkjet method, a spray method, a roll coating method, dip, roll coater, slit coater, spinner, etc. may be mentioned. From the viewpoint of productivity, transfer printing is widely used industrially, and is also suitably used in the present invention.
The coating film formed by applying the liquid crystal aligning agent by the above method can be fired to form a cured film. The step of drying after the application of the liquid crystal alignment agent is not necessarily required, but if the time from application to firing is not constant for each substrate, or if it is not immediately fired after application, the step of drying is performed Is preferred. The drying is not particularly limited as long as the solvent is removed to such an extent that the coating film shape is not deformed by the transport of the substrate and the like. For example, a method of drying on a hot plate at a temperature of 40 ° C. to 150 ° C., preferably 60 ° C. to 100 ° C., for 0.5 minutes to 30 minutes, preferably 1 minute to 5 minutes can be mentioned.

The baking temperature of the coating film formed by applying the liquid crystal aligning agent is not limited, and is, for example, 100 to 350 ° C., preferably 120 to 300 ° C., and more preferably 150 ° C. to 250 ° C. The baking time is 5 minutes to 240 minutes, preferably 10 minutes to 90 minutes, and more preferably 20 minutes to 90 minutes. The heating can be carried out by a generally known method such as a hot plate, a hot air circulating furnace, an infrared furnace and the like.
The thickness of the liquid crystal alignment film obtained by firing is not particularly limited, but is preferably 5 to 300 nm, and more preferably 10 to 100 nm.

<Liquid crystal display element>
The liquid crystal display device of the present invention can form a liquid crystal cell by a known method after forming a liquid crystal alignment film on a substrate by the above method. As a specific example of a liquid crystal display element, it is provided between two substrates arranged to face each other, a liquid crystal layer provided between the substrates, and between the substrate and the liquid crystal layer and formed by the liquid crystal aligning agent of the present invention The liquid crystal display device of the vertical alignment type comprising a liquid crystal cell having the above liquid crystal alignment film. Specifically, the liquid crystal alignment agent of the present invention is applied onto two substrates and fired to form a liquid crystal alignment film, and the two substrates are disposed such that the liquid crystal alignment films face each other, A liquid crystal layer composed of liquid crystal is held between two substrates, that is, a liquid crystal layer is provided in contact with the liquid crystal alignment film, and ultraviolet light is applied while applying a voltage to the liquid crystal alignment film and the liquid crystal layer. It is a liquid crystal display element of a vertical alignment system having a liquid crystal cell to be manufactured.

  The liquid crystal alignment film formed of the liquid crystal alignment agent of the present invention is irradiated with ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer to polymerize the polymerizable compound, and the photoreactivity of the polymer By reacting the side chains or the photoreactive side chains of the polymer with the polymerizable compound, the alignment of the liquid crystal can be fixed more efficiently, and the liquid crystal display device can have a remarkably excellent response speed.

  The substrate used for the liquid crystal display element of the present invention is not particularly limited as long as it is a substrate having high transparency, but usually, it is a substrate on which a transparent electrode for driving liquid crystal is formed on the substrate. As a specific example, the same one as the substrate described for the liquid crystal alignment film can be mentioned. Although a substrate provided with a conventional electrode pattern or protrusion pattern may be used, in the liquid crystal display device of the present invention, a line of 1 to 10 μm, for example, is used on one side substrate because the liquid crystal aligning agent of the present invention is used. The liquid crystal display device of this structure can simplify the manufacturing process and has a high transmittance. You can get

In addition, as a highly functional element such as a TFT type element, one in which an element such as a transistor is formed between an electrode for driving liquid crystal and a substrate is used.
In the case of a transmission type liquid crystal display element, it is general to use the above-mentioned substrate, but in the reflection type liquid crystal display element, it is also possible to use an opaque substrate such as a silicon wafer if it is only one side of the substrate. It is possible. At that time, a material such as aluminum that reflects light can also be used for the electrode formed on the substrate.

The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited, and a liquid crystal material used in the conventional vertical alignment method, for example, negative type such as MLC-6608 or MLC-6609 manufactured by Merck Ltd. Liquid crystals can be used. In addition, as the PSA mode, for example, a liquid crystal containing a polymerizable compound as represented by the following formula can be used.

  In the present invention, as a method of holding the liquid crystal layer between two substrates, known methods can be mentioned. For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, and spacers such as beads are dispersed on the liquid crystal alignment film on one of the substrates so that the surface on which the liquid crystal alignment film is formed is inside. There is a method in which the other substrate is attached and the liquid crystal is injected under reduced pressure to seal it. In addition, a pair of substrates on which a liquid crystal alignment film is formed is prepared, and spacers such as beads are dispersed on the liquid crystal alignment film on one of the substrates and then liquid crystal is dropped, and then the surface on the side where the liquid crystal alignment film is formed. The liquid crystal cell can also be manufactured by a method in which the other substrate is attached and sealed so that the inner side is inside. The thickness of the spacer is preferably 1 to 30 μm, more preferably 2 to 10 μm.

  The process of producing a liquid crystal cell by irradiating an ultraviolet-ray, applying a voltage to a liquid crystal aligning film and a liquid crystal layer, for example applies an electric voltage between the electrodes currently installed on the board | substrate, An electric field is applied to a liquid crystal aligning film and a liquid crystal layer Is applied, and the method of irradiating an ultraviolet-ray, hold | maintaining this electric field is mentioned. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, preferably 5 to 20 Vp-p. The irradiation dose of the ultraviolet light is, for example, 1 to 60 J, preferably 40 J or less, and the smaller the ultraviolet irradiation dose, the less the reliability deterioration caused by the destruction of the members constituting the liquid crystal display element can be reduced. This is preferable because the production efficiency is increased.

  As described above, when ultraviolet light is irradiated while applying a voltage to the liquid crystal alignment film and the liquid crystal layer, the polymerizable compound reacts to form a polymer, and the direction in which the liquid crystal molecules are tilted is stored by this polymer. The response speed of the obtained liquid crystal display can be increased. In addition, when a liquid crystal alignment film and a liquid crystal layer are irradiated with ultraviolet light while applying a voltage, a polyimide precursor having side chains for aligning liquid crystals vertically and light reactive side chains, and this polyimide precursor as an imide The photoreactive side chains of at least one type of polymer selected from polyimides obtained by polymerization and the photoreactive side chains of the polymer react with the polymerizable compound, so that the liquid crystal display device obtained Response speed can be increased.

Hereinafter, the present invention will be more specifically described by way of examples, but the present invention is not limited by these examples.
<Synthesis of diamine>

Synthesis Example 1

Step 1: Synthesis of 1- (4- (2,4-dinitrophenoxy) ethoxy) phenyl) -2-hydroxy-2-methylpropanone In a 2 L four-necked flask equipped with a stirrer and a nitrogen inlet, 100.0 g ([Mw: 186.10 g / mol], 0.538 mol) of dinitrofluorobenzene, 120.6 g ([Mw: 2-hydroxy-4 '-(2-hydroxyethoxy) -2-methylpropiophenone : 224.25 g / mol], 0.538 mol), 81.7 g of triethylamine ([Mw: 101.19 g / mol], 0.807 mol), 1000 g of THF, and the mixture was refluxed for 24 hours. After completion of the reaction, the reaction solution was concentrated by a rotary evaporator, ethyl acetate was added, and the mixture was washed several times with pure water and physiological saline and then dried over anhydrous magnesium sulfate.

Anhydrous magnesium sulfate is removed by filtration, concentrated by a rotary evaporator, and recrystallized with ethyl acetate and normal hexane to obtain 157.0 g of a milky white solid ([Mw: 390.34 g / mol], 0.402 mol, yield) : 75%). It confirmed by the nuclear magnetic resonance spectrum (< ¹ > H-NMR spectrum) of the hydrogen atom in a molecule. The measurement data is shown below.
¹ H NMR (400 MHz, CDCl ₃ ) δ: 8.75 (Ar: 1 H), 8.48 to 8. 45 (Ar: 1 H), 8.09 to 8.05 (Ar: 2 H), 7.34 To 7.31 (Ar: 1 H) 7.00 to 6.96 (Ar: 2 H), 4.65 to 4. 63 (-CH2-: 2 H), 4.52 to 4. 49 (-CH2-: 2 H) ), 4.16 (-OH: 1 H), 1.66 to 1.60 (-CH 3 × 2, 6 H) Total: 18 H

Step 2 Synthesis of 1- (4- (2,4-diaminophenoxy) ethoxy) phenyl) -2-hydroxy-2-methylpropanone (DA-1) In a 1 L four-necked flask, the dinitrobenzene derivative obtained in Step 1 is prepared. Measure 10.0 g of 0 g ([Mw: 390.34 g / mol], 0.256 mol) and iron-doped platinum carbon (3 wt% manufactured by Evonic), add 500 ml of THF, add vacuum degassing and hydrogen substitution. Well done, let react at room temperature for 24 hours.

After completion of the reaction, platinum carbon was removed by a PTFE membrane filter, and the filtrate was removed by a rotary evaporator to precipitate a solid. The obtained solid is washed with isopropyl alcohol by heating and further dried under reduced pressure to obtain 72.7 g of a light pink solid which is a target compound ([Mw: 330.38 g / mol], 0.220 mol yield) : 86%). ^{The 1} H-NMR spectrum measurement data are shown below.
¹ H NMR (400 MHz, CDCl ₃ ) δ: 8.09 to 8.05 (Ar: 2H), 7.01 to 6.97 (Ar: 2H), 6.70 to 6.68 (Ar: 1H) , 6.12 (Ar: 1 H), 4. 36 to 4. 33 (-CH 2-: 2 H), 4. 29 to 4. 27 (-OH &-CH 2-: 3 H), 3.7 (-NH 2: 2 H) ), 3.39 (-NH2: 2H), 1.64 to 1.63 (-CH3 x 2: 6H) Total: 22H

Ｓｔｅｐ１ ２−（４−（２−ヒドロキシ−２−メチルプロパノイル）フェノキシ）エチル ３，５−ジニトロベンゾエートの合成
攪拌子と窒素導入管を備えた２Ｌ四口フラスコに、２−ヒドロキシ−４’−（２−ヒドロキシエトキシ）−２−メチルプロピオフェノンを１００．０ｇ（[Ｍｗ：２２４．２５ｇ／ｍｏｌ]、０．４４６ｍｏｌ）、ピリジンを１１８．６ｇ（[Ｍｗ：７９．１０ｇ／ｍｏｌ]、１．５０ｍｏｌ）、ＴＨＦを１０００ｇ加え、１０℃以下に保ったまま少しずつ３，５−ジニトロ安息香酸クロリドを１２３．３ｇ（[Ｍｗ：２３０．５６ｇ／ｍｏｌ]、０．５３５ｍｏｌ）、３０分後室温に戻し１２時間反応させた。反応終了を確認後、ロータリーエバポレーターで濃縮し、酢酸エチルを加え、炭酸カリウム水溶液（１０％溶液）にて数回洗浄し、更に純水と生理食塩水にて数回洗浄した後、無水硫酸マグネシウムで乾燥させた。 (Composition example 2)

Step 1 Synthesis of 2- (4- (2-hydroxy-2-methylpropanoyl) phenoxy) ethyl 3,5-dinitrobenzoate In a 2 L four-necked flask equipped with a stirrer and a nitrogen inlet tube, 2-hydroxy-4′- 100.0 g ([Mw: 224.25 g / mol], 0.446 mol) of (2-hydroxyethoxy) -2-methylpropiophenone, 118.6 g ([Mw: 79.10 g / mol], 1 of pyridine .50 mol), 1000 g of THF added, 123.3 g ([Mw: 230.56 g / mol], 0.535 mol) of 3,5-dinitrobenzoic acid chloride little by little while keeping the temperature at 10 ° C. or less, after 30 minutes at room temperature The mixture was allowed to react for 12 hours. After confirming the completion of the reaction, the solution is concentrated by a rotary evaporator, ethyl acetate is added, and the solution is washed several times with aqueous potassium carbonate solution (10% solution), and further washed several times with pure water and physiological saline, and then anhydrous magnesium sulfate Dried.

Anhydrous magnesium sulfate was removed by filtration and concentrated by a rotary evaporator to obtain 162.3 g ([Mw: 418.35 g / mol], 0.388 mmol, yield: 76%) of a target yellow liquid. . ^{The 1} H-NMR spectrum measurement data are shown below.
¹ H NMR (400 MHz, CDCl ₃ ) δ: 9.24 (Ar: 1 H), 9. 18 (Ar: 2 H), 8.10 to 8.07 (Ar: 2 H), 7.02 to 6.98 (Ar: 2H), 4.86 to 4.84 (-CH2-: 2H), 4.47 to 4.44 (-CH2-: 2H), 4.15 to 4.10 (-OH: 1H), 1.64 to 1.61 (-CH3 x 2: 6H) Total: 18H

Step 2 Synthesis of 2- (4- (2-hydroxy-2-methylpropanoyl) phenoxy) ethyl 3,5-diaminobenzoate (DA-2) 150.0 g of the dinitrobenzene derivative obtained in Step 1 in a 1 L four-necked flask [Mw: 390.34 g / mol], 0.384 mol) and 10.0 g of palladium carbon (5 wt% water-containing product) are weighed out, 500 ml of THF is added, vacuum degassing and hydrogen substitution are sufficiently performed, and 24 hours at room temperature It was made to react.

After completion of the reaction, palladium carbon was removed by a PTFE membrane filter, and the filtrate was removed by a rotary evaporator to precipitate a solid. The obtained solid is recrystallized with a mixed solvent of ethyl acetate and normal hexane (weight ratio: 2: 1) and dried under reduced pressure to obtain 124.0 g of a white solid which is a target compound ([Mw: 358 .39 g / mol], 0.346 mol yield: 90%) were obtained. ^{The 1} H-NMR spectrum measurement data are shown below.
¹ H NMR (400 MHz, d ₆ -DMSO) δ: 8.21 to 8.20 (Ar: 2 H), 7.06 to 7.03 (Ar: 2 H), 6.45 (Ar: 2 H), 6 .40 (Ar: 1 H), 6.03 (-OH: 1 H), 5.01 (-NH2 x 2: 4 H), 4.53 to 4.52 (-CH2-: 2 H), 4.37 to 4 .36 (-CH2-: 2H), 1.39 (-CH3 x 2: 6H) Total: 22H

<Preparation of Liquid Crystal Alignment Agent>
Abbreviations in the following are as follows.
(Acid dianhydride)
BODA: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid dianhydride CBDA: 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride PMDA: trimellitic anhydride TCA: 2,3,5-tricarboxycyclopentylacetic acid-1,4,2,3-dianhydride

ＤＡ−１〜ＤＡ−２：合成例１、２で得られた下記のラジカル発生ジアミン

(Diamine)
m-PDA: m-phenylenediamine DBA: 3,5-diaminobenzoic acid 3 AMPDA: 3,5-diamino-N- (pyridin-3-ylmethyl) benzamide
4DABP: 4,4'-diaminobenzophenone shown below

DA-1 to DA-2: The following radical generating diamines obtained in Synthesis Examples 1 and 2

DA-3 to DA-4: Photoreactive diamines described below

DA-6 to DA-9: Vertically oriented diamine described below

<Solvent>
NMP: N-methyl-2-pyrrolidone BCS: butyl cellosolve <additive>
3 AMP: 3-picolylamine <polymerizing compound>
Polymerizable compounds represented by the following formulas RM1 and RM2

KIP150：下記に示すポリスチレン系ラジカル開始機能付きポリマー（SYNASIA社製）

<Liquid Crystal Containing Polymerizable Compound>
30 mg (0.3 wt% relative to liquid crystal) of the polymerizable compound RM3 is added to a negative liquid crystal MLC-6608 (10.0 g) manufactured by Merck, and the liquid crystal (LC1) containing the polymerizable compound is dissolved at 120 ° C. Prepared.
<Others>
IPDI: Isophorone diisocyanate shown below

KIP150: Polystyrene based radical initiating polymer shown below (SYNASIA)

<Measurement of Molecular Weight of Polyimide>
Device: High temperature gel permeation chromatography (GPC) device (SSC-7200) manufactured by Senshu Science Co., Ltd.
Column: Shodex column (KD-803, KD-805)
Column temperature: 50 ° C
Eluent: N, N'-dimethylformamide (as additive, 30 mmol / L of lithium bromide-hydrate (LiBr.H ₂ O), 30 mmol / L of phosphoric acid / anhydrous crystal (o-phosphoric acid), Tetrahydrofuran (THF) 10 ml / L)
Flow rate: 1.0 ml / min Standard sample for preparation of calibration curve: Toso TSK standard polyethylene oxide (molecular weight about 9000,000, 150,000, 100,000, 30,000), and polymer laboratory polyethylene glycol ( Molecular weight about 12,000, 4,000, 1,000).

<Measurement of imidation ratio of polyimide>
Place 20 mg of polyimide powder in an NMR sample tube (NMR sampling tube standard φ5 manufactured by Kusano Science Co., Ltd.), add 1.0 ml of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05% TMS mixture), and add ultrasonic waves. It was completely dissolved. This solution was subjected to proton NMR measurement at 500 MHz with an NMR meter (JNW-ECA500) manufactured by Nippon Denshi Datum Co., Ltd. The imidation ratio is determined using a proton derived from a structure that does not change before and after imidization as a reference proton, and a peak integrated value of this proton and a proton peak derived from the NH group of the amic acid appearing around 9.5 to 10.0 ppm It calculated | required by the following formula using integration value. In the following formula, x is a proton peak integrated value derived from the NH group of the amic acid, y is a peak integrated value of the reference proton, and α is a proton of the NH group of the amic acid in the case of polyamic acid (imidation ratio is 0%) It is the number ratio of reference protons to one.
Imidation ratio (%) = (1−α · x / y) × 100

Example 1
CBDA (1.86 g, 10.0 mmol), DA-1 (2.51 g, 7.0 mmol), DA-6 (1.14 g, 3.0 mmol) were reacted in NMP (22.1 g) for 10 hours After that, NMP (36.8 g) and BCS (27.6 g) were added and stirred for 5 hours to obtain a liquid crystal aligning agent (A).
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (A), and it is made to stir and dissolve at room temperature for 3 hours, and liquid crystal alignment An agent (A1) was prepared.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM2 is added with respect to 10.0 g of said liquid crystal aligning agent (A), and it is made to stir and dissolve at room temperature for 3 hours, and liquid crystal alignment An agent (A2) was prepared.

(Example 2)
CBDA (1.86 g, 10.0 mmol), DA-1 (1.08 g, 3.0 mmol), DA-4 (1.06 g, 4.0 mmol), DA-7 (1.30 g, 3.0 mmol) After reacting for 10 hours in NMP (21.2 g), NMP (35.3 g) and BCS (26.5 g) were added and stirred for 5 hours to obtain a liquid crystal aligning agent (B).
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (B), it is made to stir and melt | dissolve at room temperature for 3 hours, and liquid crystal aligning agent (B1) was prepared.

(Example 3)
PMDA (0.65 g, 3.0 mmol), DBA (0.46 g, 3.0 mmol), DA-2 (0.73 g, 2.0 mmol), DA-3 (0.93 g, 2.0 mmol), DA- After reacting 9 (1.20 g, 3.0 mmol) in NMP (15.9 g) for 30 minutes, add CBDA (1.31 g, 7.0 mmol) and NMP (5.3 g) for another 10 hours of reaction. The NMP (35.2 g) and BCS (26.4 g) were added and stirred for 5 hours to obtain a liquid crystal aligning agent (C).
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agents (C), and it is made to stir and dissolve at room temperature for 3 hours, and liquid crystal aligning agent (C1) was prepared.

(Example 4)
Dissolve BODA (2.38, 10.0 mmol), DA-2 (4.39 g, 13.0 mmol), DA-9 (2.28 g, 6.0 mmol) in NMP (32.4 g), 60 ° C. The reaction was carried out for 5 hours, and then CBDA (1.75 g, 9.0 mmol) and NMP (10.8 g) were added and reacted at 40 ° C. for 10 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (50 g) and diluting to 6 mass%, acetic anhydride (5.4 g) and a pyridine (2.8 g) were added as an imidation catalyst, and it was made to react at 50 degreeC for 3 hours. The reaction solution was poured into methanol (700 ml) and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain a polyimide powder (D). The imidation ratio of this polyimide was 51%, the number average molecular weight was 17000, and the weight average molecular weight was 38000.
NMP (44.0 g) was added to the obtained polyimide powder (D) (6.0 g), and stirred at 50 ° C. for 5 hours for dissolution. 6.0 g of 3 AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added to this solution, and liquid crystal aligning agent (D1) was obtained by stirring at room temperature for 5 hours.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (D1), it is made to stir and melt | dissolve at room temperature for 3 hours, (D2) was prepared.

(Example 5)
BODA (2.38, 10.0 mmol), DBA (0.87 g, 6.0 mmol), DA-2 (1.26 g, 4.0 mmol), DA-3 (1.77 g, 4.0 mmol), DA- 9 (2.28 g, 6.0 mmol) is dissolved in NMP (30.7 g) and allowed to react at 60 ° C. for 5 hours, then CBDA (1.68 g, 9.0 mmol) and NMP (10.2 g) In addition, it was reacted at 40 ° C. for 10 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (45 g) and diluting to 6 mass%, acetic anhydride (5.1 g) and a pyridine (2.6 g) were added as an imidation catalyst, and it was made to react at 50 degreeC for 3 hours. The reaction solution was poured into methanol (650 ml) and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 60 ° C. to obtain polyimide powder (E). The imidation ratio of this polyimide was 52%, the number average molecular weight was 13,000, and the weight average molecular weight was 27,000.
NMP (44.0 g) was added to the obtained polyimide powder (E) (6.0 g), and stirred at 50 ° C. for 5 hours for dissolution. 6.0 g of 3 AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added to this solution, and the liquid crystal aligning agent (E1) was obtained by stirring at room temperature for 5 hours.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (E1), it is made to stir and dissolve at room temperature for 3 hours, and liquid crystal alignment An agent (E2) was prepared.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM2 is added with respect to 10.0 g of said liquid crystal aligning agent (E1), it is made to stir and melt | dissolve at room temperature for 3 hours, and liquid crystal alignment An agent (E3) was prepared.

(Example 6)
TCA (2.13, 10.0 mmol), 3 AMPDA (1.84 g, 8.0 mmol), DA-1 (2.04 g, 6.0 mmol), DA-8 (2.98 g, 6.0 mmol) with NMP ( After dissolving in 32.0 g) and reacting at 80 ° C. for 5 hours, CBDA (1.68 g, 9.0 mmol) and NMP (10.7 g) are added and reacted at 40 ° C. for 10 hours to make a polyamic acid solution Obtained.
After adding NMP to this polyamic acid solution (45 g) and diluting to 6 mass%, acetic anhydride (4.9 g) and a pyridine (2.5 g) were added as an imidation catalyst, and it was made to react at 50 degreeC for 3 hours. The reaction solution was poured into methanol (650 ml) and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 60 ° C. to obtain polyimide powder (F). The imidation ratio of this polyimide was 50%, the number average molecular weight was 16000, and the weight average molecular weight was 33000.
NMP (44.0 g) was added to the obtained polyimide powder (F) (6.0 g), and stirred at 50 ° C. for 5 hours for dissolution. 6.0 g of 3 AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added to this solution, and the liquid crystal aligning agent (F1) was obtained by stirring at room temperature for 5 hours.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (F1), it is made to stir and melt | dissolve at room temperature for 3 hours, and liquid crystal alignment An agent (F2) was prepared.

(Comparative example 1)
CBDA (1.86 g, 10.0 mmol), m-PDA (0.76 g, 7.0 mmol), DA-9 (1.14 g, 3.0 mmol) were reacted in NMP (15.1 g) for 10 hours Thereafter, NMP (25.1 g) and BCS (18.8 g) were added, and stirred for 5 hours to obtain a polyamic acid solution (G).
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (G), it is made to stir and melt | dissolve at room temperature for 3 hours, and liquid crystal alignment An agent (G1) was prepared.

(Comparative example 2)
Dissolve BODA (2.38, 10.0 mmol), DBA (2.02 g, 13.0 mmol), DA-9 (2.28 g, 6.0 mmol) in NMP (25.3 g) at 80 ° C. 5 After reacting for time, CBDA (1.75 g, 9.0 mmol) and NMP (8.4 g) were added and reacted at 40 ° C. for 10 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (35 g) and diluting to 6 mass%, acetic anhydride (4.8 g) and a pyridine (2.5 g) were added as an imidation catalyst, and it was made to react at 50 degreeC for 3 hours. The reaction solution was poured into methanol (500 ml) and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain polyimide powder (H). The imidation ratio of this polyimide was 50%, the number average molecular weight was 18,000, and the weight average molecular weight was 37,000.
NMP (44.0 g) was added to the obtained polyimide powder (H) (6.0 g), and stirred at 50 ° C. for 5 hours for dissolution. 6.0 g of 3 AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added to this solution, and the liquid crystal aligning agent (H1) was obtained by stirring at room temperature for 5 hours.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (H1), it is made to stir and melt | dissolve at room temperature for 3 hours, and liquid crystal alignment An agent (H2) was prepared.

<Fabrication of liquid crystal cell>
(Example 7)
Using the liquid crystal aligning agent (A1) obtained in Example 1, a liquid crystal cell was produced in the following procedure. The liquid crystal aligning agent (A1) obtained in Example 1 is spin-coated on the ITO surface of an ITO electrode substrate on which an ITO electrode pattern having a pixel size of 100 μm × 300 μm and a line / space of 5 μm is formed. After drying for 90 seconds on a hot plate of the above, baking was performed for 30 minutes in a hot air circulating oven at 200 ° C. to form a liquid crystal alignment film with a film thickness of 100 nm.
The liquid crystal aligning agent (A1) is spin-coated on the ITO surface on which the electrode pattern is not formed, dried on a hot plate at 80 ° C. for 90 seconds, and baked for 30 minutes in a hot air circulating oven at 200 ° C. A liquid crystal alignment film having a thickness of 100 nm was formed.

After sprinkling a 4 μm bead spacer on the liquid crystal alignment film of one of the above two substrates, a sealant (solvent-type thermosetting type epoxy resin, struct bond XN-1500T manufactured by Mitsui Chemicals, Inc.) Was printed. Next, with the surface of the other substrate on which the liquid crystal alignment film was formed facing inside, the substrate was bonded to the previous substrate, and then the sealing agent was cured to produce an empty cell. A liquid crystal MLC-6608 (trade name of Merck & Co., Ltd.) was injected into this empty cell by a pressure reduction injection method to produce a liquid crystal cell.
The response speed of the obtained liquid crystal cell was measured by the following method. Thereafter, in a state where a DC voltage of 20 V was applied to the liquid crystal cell, 10 J of UV was passed from the outside of the liquid crystal cell through a band pass filter of 365 nm. After that, the response speed was measured again, and the response speed before and after UV irradiation was compared. Moreover, the pretilt angle of the pixel part was measured about the cell after UV irradiation. The results are shown in Table 1.

<Method of measuring response speed>
First, a liquid crystal cell was disposed between a pair of polarization plates in a measurement apparatus configured by a backlight, a pair of polarization plates in a cross nicol state, and a light amount detector in this order. At this time, the pattern of the ITO electrode in which the line / space was formed was made to be at an angle of 45 ° with respect to cross nicol. Then, a rectangular wave with a voltage of ± 6 V and a frequency of 1 kHz is applied to the above-mentioned liquid crystal cell, a change until the luminance observed by the light amount detector is saturated is taken in by an oscilloscope, and the luminance when no voltage is applied is calculated. A voltage of 0%, ± 4 V was applied, the value of saturated luminance was 100%, and the time taken for the luminance to change from 10% to 90% was taken as the response speed.
<Measurement of pretilt angle>
An LCD analyzer LCA-LUV42A manufactured by Meiryo Technica Co., Ltd. was used.

(Examples 8 to 14, Comparative Examples 3 and 4)
The same procedure as in Example 7 is carried out except that the liquid crystal aligning agent shown in Table 1 is used instead of the liquid crystal aligning agent (A1) to measure the response speed before and after UV irradiation and the pretilt angle I did. These results are summarized in Table 1 below.

As shown in Table 1, in the example, it was confirmed that the tilt angle was developed even by irradiation with ultraviolet light of wavelength 365 nm. On the other hand, in the comparative example, even if the liquid crystal alignment film contained a polymerizable compound, a sufficient tilt angle could not be expressed.
This is because, in the liquid crystal aligning agent of the comparative example, the polymerizable compound itself hardly absorbs ultraviolet light of 365 nm, so that sufficient radicals for initiating the polymerization reaction are not generated in the liquid crystal alignment film having no radical generation site Is considered to be On the other hand, in the liquid crystal aligning agent of the example, since sufficient radicals are generated even when irradiated with ultraviolet light on the long wavelength side, it is considered that the polymerizable compound is polymerized at the interface of the liquid crystal alignment film to form a tilt angle.

(Example 15)
A liquid crystal cell was produced in the same manner as in Example 7, except that a liquid crystal aligning agent (D1) was used instead of the liquid crystal aligning agent (A1) and a liquid crystal containing a polymerizable compound was used. In a state where a DC voltage of 20 V was applied to this liquid crystal cell, UVs passing through a band pass filter of 365 nm were irradiated from 7V and 15J from the outside of the liquid crystal cell, and the response speed of each liquid crystal cell was compared. The pretilt angle was also measured. The results are shown in Table 2.

(Comparative example 5)
A liquid crystal cell was produced in the same manner as in Example 7, except that a liquid crystal aligning agent (H1) was used instead of the liquid crystal aligning agent (A1) and a liquid crystal containing a polymerizable compound was used. In a state where a DC voltage of 20 V was applied to this liquid crystal cell, UVs passing through a band pass filter of 365 nm were irradiated from 7V and 15J from the outside of the liquid crystal cell, and the response speed of each liquid crystal cell was compared. The pretilt angle was also measured.

  As shown in Table 2, in the case of Example 15, it was confirmed that there is sufficient improvement in response speed and ability to form a tilt angle even when the irradiation amount of ultraviolet light is as small as 7 J. On the other hand, in Comparative Example 5, when the irradiation amount of the ultraviolet light was small, the tilt angle hardly appeared, and it was confirmed that a large amount of ultraviolet irradiation was required to express the tilt angle.

(Example 16)
NMP (0.89 g, 4.0 mmol), DA-1 (1.32 g, 4.0 mmol), DA-6 (1.52 g, 4.0 mmol), 3 AMPDA (0.48 g, 2.0 mmol) After dissolving in 16.0 g) and reacting for 5 hours, CBDA (1.14 g, 5.8 mmol) and NMP (5.4 g) are added and reacted at room temperature for 10 hours to obtain polyurea-amic acid (PU-PAA). ) Solution was obtained. The Mn of this polymer was 11,000 and the Mw was 28,000.
NMP (30.3 g), 3 AMP (5.4 g of 1 mass% NMP solution), BC (26.8 g) are added to this PU-PAA solution (26.8 g), and it dilutes to 6 mass%, and stirs at room temperature for 5 hours Thus, a liquid crystal aligning agent (I1) was obtained.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 obtained by the synthesis example is added with respect to 10.0 g of said liquid crystal aligning agent (I1), and it stirs at room temperature for 3 hours. It was made to melt and liquid crystal aligning agent (I2) was prepared.

(Example 17)
NMP (44.0 g) was added to KIP150 (6.0 g) and stirred for 5 hours for dissolution. NMP (20.0g) and BCS (30.0g) were added to this solution, and it diluted to 6 mass%, and obtained the polymer solution (J1) by stirring at room temperature for 5 hours.
Further, 3.0 g of the polymer solution (J1) and 0.06 g (10% by mass relative to the solid content) of the polymer solution (J1) were added to 7.0 g of the liquid crystal aligning agent (H1) of Comparative Example 2 at room temperature The mixture was stirred for 3 hours and uniformly dissolved to prepare a liquid crystal aligning agent (J2).

(Example 18)
BODA (3.0, 12.0 mmol), 3 AMPDA (1.45 g, 6.0 mmol), DA-6 (4.57 g, 12.0 mmol), DA-1 (3.96 g, 12.0 mmol) with NMP ( After dissolving in 49.4 g) and reacting at 60 ° C. for 5 hours, CBDA (3.47 g, 17.7 mmol) and NMP (16.5 g) are added and reacted at 40 ° C. for 10 hours to make the polyamic acid solution Obtained.
After adding NMP to this polyamic acid solution (80 g) and diluting to 6 mass%, acetic anhydride (14.8 g) and a pyridine (4.6 g) were added as an imidation catalyst, and it was made to react at 70 degreeC for 3 hours. The reaction solution was poured into methanol (1060 ml) and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain polyimide powder (K). The imidation ratio of this polyimide was 72%, Mn was 17000, and Mw was 54000.
NMP (44.0 g) was added to the obtained polyimide powder (K) (6.0 g), and stirred at 70 ° C. for 12 hours for dissolution. 6.0 g of 3 AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added to this solution, and the liquid crystal aligning agent (K1) was obtained by stirring at room temperature for 5 hours.
Moreover, 0.06 g (10 mass% with respect to solid content) of polymeric compound RM1 is added with respect to 10.0 g of said liquid crystal aligning agent (K1), and it is made to stir and dissolve at room temperature for 3 hours, and liquid crystal aligning agent (K2) was prepared.

(Comparative example 6)
BODA (3.0, 12.0 mmol), 3 AMPDA (1.45 g, 6.0 mmol), DA-6 (4.57 g, 12.0 mmol), 4 DABP (2.55 g, 12.0 mmol) with NMP (45. After dissolving in 1 g) and reacting at 60 ° C. for 5 hours, CBDA (3.47 g, 17.7 mmol) and NMP (15.5 g) were added and reacted at 40 ° C. for 10 hours to obtain a polyamic acid solution .
After adding NMP to this polyamic acid solution (70 g) and diluting to 6 mass%, acetic anhydride (14.2 g) and a pyridine (4.4 g) were added as an imidation catalyst, and it was made to react at 70 degreeC for 3 hours. The reaction solution was poured into methanol (940 ml) and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain polyimide powder (L). The imidation ratio of this polyimide was 70%, Mn was 14000, and Mw was 41000.
NMP (44.0 g) was added to the obtained polyimide powder (L) (6.0 g) and stirred at 70 ° C. for 12 hours for dissolution. 6.0 g of 3 AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added to this solution, and liquid crystal aligning agent (L1) was obtained by stirring at room temperature for 5 hours.
Furthermore, 0.06 g (10% by mass relative to the solid content) of the polymerizable compound RM1 is added to 10.0 g of the above-mentioned liquid crystal aligning agent (L1), stirred at room temperature for 3 hours to dissolve, and a liquid crystal aligning agent (L2) was prepared.

<Production and evaluation of liquid crystal cell>
(Example 19)
The same procedure as in Example 7 was carried out except using the liquid crystal aligning agent (I2) instead of the liquid crystal aligning agent (A1), and the response speed before and after UV irradiation was compared. The pretilt angle was also measured.
Example 20
The same operation as in Example 7 was performed except that the liquid crystal aligning agent (J2) was used instead of the liquid crystal aligning agent (A1), and the response speed before and after UV irradiation was compared. The pretilt angle was also measured.

(Example 21)
The same procedure as in Example 7 was carried out except that the liquid crystal aligning agent (K2) was used instead of the liquid crystal aligning agent (A1), and the response speed before and after UV irradiation was compared. The pretilt angle was also measured.
(Comparative example 7)
The same operation as in Example 7 was performed except that the liquid crystal aligning agent (L2) was used instead of the liquid crystal aligning agent (A1), and the response speed before and after UV irradiation was compared. The pretilt angle was also measured.

From the results in the above Examples 19 and 20, even if a polymer having a main chain structure other than polyimide (polyurea structure or polystyrene structure) is used, a long wavelength such as 365 nm can be obtained by introducing a radical initiation site into the side chain site. It has been confirmed that even with ultraviolet irradiation of the above, a sufficient pretilt angle is developed.
On the other hand, it was found that when the radical initiation site is introduced into the main chain skeleton of the polymer as shown in Comparative Example 7, the ability to express the pretilt angle tends to be weaker than when introduced into the side chain site.
In general, it is considered that a polymerization reaction in which a polymerizable compound reacts to form a tilt angle by ultraviolet irradiation efficiently occurs at an interface between a liquid crystal alignment film and a liquid crystal in contact therewith to form a pretilt angle. . However, when the radical site is in the main chain skeleton as in Comparative Example 7, the radical generated by the ultraviolet irradiation is present in the polymer and can not efficiently participate in the reaction at the interface with the liquid crystal. It is thought that it is not.

The liquid crystal aligning agent of the present invention is useful not only as a liquid crystal aligning agent for producing a liquid crystal display element of vertical alignment type such as PSA type liquid crystal display, SC-PVA type liquid crystal display, but also by rubbing treatment and photo alignment treatment It can be suitably used also in the use of the liquid crystal aligning film produced.
In addition, the entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2013-182351 filed on September 3, 2013 are cited herein as the disclosure of the specification of the present invention, It is what it takes.

Claims (3)

At least one polymer selected from the group consisting of a polyimide precursor having a side chain structure represented by the following formula (I) and a polyimide obtained by imidizing the same.

(R ₁ and R ₂ are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group, a benzyl group, or a phenethyl group, and in the case of an alkyl group or an alkoxy group, a ring is formed by R ₁ and R ₂ T ₁ and T ₂ each independently represent a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, _{-N (CH 3) -, -} CON (CH 3) -, or -N _(CH 3) a CO- .S represents a single bond, or unsubstituted or number of carbon atoms 1 which are substituted by fluorine atoms 20 alkylene groups (however, the —CH ₂ — or CF ₂ — alkylene group may be substituted by —CH = CH—, and these groups may be substituted if any of the following groups are not adjacent to each other: May be replaced by; -O-, -COO- -OCO -, - NHCO -, - CONH -, -. NH-, a divalent carbocyclic or divalent heterocyclic) is .Q represents the following structure.

(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ represents -CH _2- , -NR-, -O- or -S-.) The diamine represented by following formula (I).

(In the formula, the definitions of R ₁ , R ₂ , T ₁ , T ₂ , S, Q and R are the same as in the above formula (I).) Any diamine represented by the following formula.