JP7375545B2 - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Description

The present invention relates to a liquid crystal aligning agent with excellent filterability and printability, a liquid crystal aligning film with excellent liquid crystal alignment obtained from the liquid crystal aligning agent, a method for producing the same, and a liquid crystal display element.

As liquid crystal alignment films for liquid crystal display elements, so-called polyimide-based liquid crystal alignment films are widely used, which are made by coating and baking a liquid crystal alignment agent whose main component is a solution of polyimide precursors such as polyamic acid (polyamic acid) or soluble polyimide. has been done. In the production of such a liquid crystal aligning agent, in order to remove foreign substances contained in the solution of the liquid crystal aligning agent, a method has conventionally been used in which a polyimide precursor or polyimide is dissolved in a solvent and then filtered using a filter. (Patent Document 1).

Japanese Patent Publication No. 08-262450

In the field of liquid crystal alignment films, thin films of about several hundred nanometers have conventionally been used, and the presence of minute foreign matter in liquid crystal alignment agents has not been a major problem. However, recently, the need for thinner films has increased, and at the same time, it has become necessary to remove finer foreign matter than before. The removal of minute foreign matter from a solution can be achieved by filtering it with a filter with a small pore size, but if there is a large amount of foreign matter, manufacturing on a large scale will take time and cause problems in production. Become. In addition, demands for improving display quality are becoming more severe, and in addition to liquid crystal aligning agents with fewer pinholes and repellents, there is a need for liquid crystal aligning films that have better liquid crystal alignment properties than ever before.

In view of the above problems, an object of the present invention is to provide a liquid crystal alignment agent with excellent filterability and printability, a liquid crystal alignment film with excellent liquid crystal alignment properties obtained from the liquid crystal alignment agent, and a liquid crystal display element equipped with the liquid crystal alignment film. Our goal is to provide the following.

As a result of intensive studies to solve the above problems, the present inventors have found that various properties can be simultaneously improved by combining a polymer with a specific structure introduced and a solvent containing a specific solvent. I discovered that.
The present invention is based on this knowledge and has the following gist.
At least one type selected from polyamic acids, polyamic acid esters (hereinafter, polyamic acids and polyamic acid esters are also collectively referred to as polyimide precursors) having the structure of the following formula [1], and polyimides that are imidized products thereof. A liquid crystal aligning agent containing a polymer and a solvent, wherein the solvent is at least one solvent A selected from the group consisting of the following formulas (d-1) to (d-5) and the following formula (e). , a solvent containing at least one solvent B selected from the group consisting of the following formulas (B-1) to (B-4), and a liquid crystal aligning agent characterized by containing:

Ｘは、単結合、－Ｏ－、－Ｃ（ＣＨ_３）_２－、－ＮＨ－、－ＣＯ－、－ＮＨＣＯ－、－ＣＯＯ－、－（ＣＨ_２）_ｍ－、－ＳＯ_２－、－Ｏ－（ＣＨ_２）_ｍ－Ｏ－、－Ｏ－Ｃ（ＣＨ_３）_２－、－ＣＯ－（ＣＨ_２）_ｍ－、－ＮＨ－（ＣＨ_２）_ｍ－、－ＳＯ_２－（ＣＨ_２）_ｍ－、－ＣＯＮＨ－（ＣＨ_２）_ｍ－、－ＣＯＮＨ－（ＣＨ_２）_ｍ－ＮＨＣＯ－及び－ＣＯＯ－（ＣＨ_２）_ｍ－ＯＣＯ－からなる群から選ばれる２価の有機基を示表し、ｍは１～８の整数である。２つのＹは独立して下記式［Ｓ１］～［Ｓ３］又はトコフェロールから誘導される構造から選ばれる側鎖構造を示表す。

X is a single bond, -O-, -C(CH ₃ ) ₂ -, -NH-, -CO-, -NHCO-, -COO-, -(CH ₂ ) _m -, -SO ₂ -, -O -(CH ₂ ) _m -O-, -OC(CH ₃ ) ₂ -, -CO-(CH ₂ ) _m -, -NH-(CH ₂ ) _m -, -SO ₂ -(CH ₂ ) _m represents a divalent organic group selected from the group consisting of -, -CONH-(CH ₂ ) _m -, -CONH-(CH ₂ ) _m -NHCO- and -COO-(CH ₂ ) _m -OCO-, m is an integer from 1 to 8. The two Y's independently represent a side chain structure selected from the following formulas [S1] to [S3] or a structure derived from tocopherol.

Ｘ^１及びＸ^２は独立して、単結合、－（ＣＨ_２）_ａ－（ａは１～１５の整数である）、－ＣＯＮＨ－、－ＮＨＣＯ－、－ＣＯＮ（ＣＨ_３）－、－ＮＨ－、－Ｏ－、－ＣＯＯ－、－ＯＣＯ－、又は（（ＣＨ_２）_ａ１－Ａ_１）_ｍ１－（複数のａ１は独立して１～１５の整数を示し、複数のＡ_１は独立して、酸素原子、－ＣＯＯ又はＯＣＯを示し、ｍ_１は１～２である。）を示し、Ｇ^１及びＧ^２は独立して炭素数６～１２の２価の芳香族基又は炭素数３～８の２価の脂環式基から選ばれる２価の環状基であり、前記環状基上の任意の水素原子が、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、ｍ及びｎは独立して０～３の整数であって、これらの合計は１～４であり、Ｒ^１は炭素数１～２０のアルキル、炭素数１～２０のアルコキシ、又は炭素数２～２０のアルコキシアルキルであり、これらの基における任意の水素はフッ素原子で置き換えられてもよい。
Ｘ^３は、単結合、－ＣＯＮＨ－、－ＮＨＣＯ－、－ＣＯＮ（ＣＨ_３）－、－ＮＨ－、－Ｏ－、－ＣＨ_２Ｏ－、－ＣＯＯ－又はＯＣＯ－を示し、Ｒ^２は炭素数１～２０のアルキル又は炭素数２～２０のアルコキシアルキルであり、これらの基における任意の水素はフッ素原子で置き換えられてもよい。
Ｘ^４は、－ＣＯＮＨ－、－ＮＨＣＯ－、－Ｏ－、－ＣＯＯ－又はＯＣＯ－を示し、Ｒ^３はステロイド骨格を有する構造を示す。

X ¹ and X ² are independently a single bond, -(CH ₂ ) _a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH -, -O-, -COO-, -OCO-, or ((CH ₂ ) _a1 -A ₁ ) _m1 - (multiple a1 independently represent an integer from 1 to 15, and multiple A ₁ independently represent an integer of 1 to 15) represents an oxygen atom, -COO or OCO, m ₁ is 1 to 2), and G ¹ and G ² independently represent a divalent aromatic group having 6 to 12 carbon atoms or a C 3 A divalent cyclic group selected from ~8 divalent alicyclic groups, and any hydrogen atom on the cyclic group is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, It may be substituted with 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, m and n are independently integers of 0 to 3, and these The total number is 1 to 4, and R ¹ is alkyl having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, or alkoxyalkyl having 2 to 20 carbon atoms, and any hydrogen in these groups is a fluorine atom. May be replaced.
X ³ represents a single bond, -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or OCO-, and R ² represents carbon It is an alkyl group having 1 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms, and any hydrogen in these groups may be replaced with a fluorine atom.
X ⁴ represents -CONH-, -NHCO-, -O-, -COO- or OCO-, and R ³ represents a structure having a steroid skeleton.

Ｒ_１ａは炭素数１～８の１価の炭化水素基、又は当該炭化水素基における炭素－炭素結合間に「－Ｏ－」を有する１価の基を示し、Ｒ_２ａ及びＲ_２ｂは独立して炭素数１～６のアルキル基を示し、Ｒ_３ａはメチル基又はエチル基を示し、Ｒ_５ａは、炭素数１～６のアルキル基を示し、Ｒ_５ｂ及びＲ_５ｃは独立して、水素原子、炭素数１～６の１価の炭化水素基、又は当該炭化水素基の炭素－炭素結合間に「－Ｏ－」を有する１価の基を示し、ｒ_１ａ 及びｒ_１ｂ は独立して、水素原子、炭素数１～６のアルキル基を示し、ｍは２～６の整数であり、ｎは１又は２である。

R _1a represents a monovalent hydrocarbon group having 1 to 8 carbon atoms, or a monovalent group having "-O-" between the carbon-carbon bonds in the hydrocarbon group, and R _2a and R _2b are independently represents an alkyl group having 1 to 6 carbon atoms, R _3a represents a methyl group or an ethyl group, R _5a represents an alkyl group having 1 to 6 carbon atoms, and R _5b and R _5c independently represent a hydrogen atom. , represents a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a monovalent group having "-O-" between the carbon-carbon bonds of the hydrocarbon group, and r _1a and r _1b are independently, It represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, m is an integer of 2 to 6, and n is 1 or 2.

Ａ_ｐ１、Ａ_ｐ２は独立して、炭素数１～６のアルキル基を示し、Ａ_ｐ５は水素原子又は炭素数１～６のアルキル基を示し、Ａ_ｑ１は－Ｏ－又は－ＣＯＯ－を示し、Ａ_ｑ２は単結合又はカルボニル基を示し、Ａ_ｑ３は－Ｏ－を示し、Ａ_ｋ１、Ａ_ｋ２、Ａ_ｋ６は独立して、炭素数２～４のアルカンジイル基を示し、ｎ１は１～３を示す。Ａ_ｐ３、Ａ_ｐ４は、水素原子又は炭素数１～６のアルキル基を示し、Ａ_ｘは、－Ｃ（ＯＨ）Ｒ_ａ－、－ＣＨＲ_ｂ－（Ｒ_ａ、Ｒ_ｂは独立して、水素、メチル基又はエチル基である。）、－ＣＯ－又は－ＣＯＯ－＊（但し、＊はＡ_ｋ４との結合位置を示す。）を示し、Ａ_ｋ４、Ａ_ｋ５は、独立して炭素数１～４のアルキル基を示し、ｍは０～１を示し、ｎ４は１～３を示す。但しｎ４が１で、Ａ_ｋ６が炭素数２のアルカンジイル基で、Ａｐ５が炭素数４のアルキル基である場合は除く。但し、ｎ４が１で、Ａｋ６が炭素数２のアルカンジイル基で、Ａｐ５が炭素数４のアルキル基である場合は除く。

A _p1 and A _p2 independently represent an alkyl group having 1 to 6 carbon atoms, A _p5 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and A _q1 represents -O- or -COO-; , A _q2 represents a single bond or a carbonyl group, A _q3 represents -O-, A _k1 , A _k2 , and A _k6 independently represent an alkanediyl group having 2 to 4 carbon atoms, and n1 represents 1 to 4 carbon atoms. 3 is shown. A _p3 and A _p4 represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and A _x is -C(OH)R _a -, -CHR _b - (R _a and R _b are independently hydrogen , methyl group or ethyl group), -CO- or -COO-* (where * indicates the bonding position with A _k4 ), and A _k4 and A _k5 independently have a carbon number of 1. ~4 alkyl group, m represents 0-1, and n4 represents 1-3. However, cases where n4 is 1, A _k6 is an alkanediyl group having 2 carbon atoms, and Ap5 is an alkyl group having 4 carbon atoms are excluded. However, cases where n4 is 1, Ak6 is an alkanediyl group having 2 carbon atoms, and Ap5 is an alkyl group having 4 carbon atoms are excluded.

According to the present invention, a liquid crystal aligning agent with excellent filterability and printability, a liquid crystal aligning film with excellent liquid crystal aligning properties obtained from the liquid crystal aligning agent, and a liquid crystal display element equipped with the liquid crystal aligning film are obtained.

＜特定重合体＞
特定重合体は、なかでも、合成の容易性から、重合体の主鎖に式［１］の構造を有することが好ましい。ここで、重合体の主鎖とは、重合体のうち最も長い原子の連鎖からなる部分をいう。また、特定重合体において、前記式［１］の構造が主鎖以外の部分（例えば重合体の側鎖の部分）にも存在することを排除するものではない。The liquid crystal aligning agent of the present invention comprises at least one polymer (hereinafter also referred to as a specific polymer) selected from the group consisting of a polyimide precursor having the structure of the following formula [1] and polyimide which is an imidized product thereof. contains.

<Specific polymer>
Among others, it is preferable that the specific polymer has the structure of formula [1] in the main chain of the polymer from the viewpoint of ease of synthesis. Here, the main chain of a polymer refers to the portion of the polymer that is made up of the longest chain of atoms. Further, in the specific polymer, it is not excluded that the structure of the formula [1] is also present in parts other than the main chain (for example, in the side chain part of the polymer).

X in formula [1] is as defined above.
Among these, X is preferably a single bond, -O-, -NH-, or -O-(CH ₂ ) _m -O-.

式［Ｓ１］中のＸ^１及びＸ^２は上記に定義したとおりである。なかでも原料の入手性や合成の容易さの点からの観点から、単結合、－（ＣＨ_２）_ａ－（ａは１～１５の整数である）、－Ｏ－、－ＣＨ_２Ｏ－又はＣＯＯ－が好ましい。より好ましくは、単結合、－（ＣＨ_２）_ａ－（ａは１～１０の整数である）、－Ｏ－、－ＣＨ_２Ｏ－又はＣＯＯ－である。Y in formula [1] has a side chain structure selected from the following formulas [S1] to [S3] or a structure having a tocopherol skeleton.

X ¹ and X ² in formula [S1] are as defined above. Among them, from the viewpoint of availability of raw materials and ease of synthesis, single bonds, -(CH ₂ ) _a - (a is an integer from 1 to 15), -O-, -CH ₂ O-, or COO- is preferred. More preferably, it is a single bond, -(CH ₂ ) _a - (a is an integer from 1 to 10), -O-, -CH ₂ O- or COO-.

G ¹ and G ² are as defined above.
Examples of the divalent aromatic group having 6 to 12 carbon atoms include phenylene, biphenylene, and naphthalene. Examples of the divalent alicyclic group having 3 to 8 carbon atoms include cyclopropylene and cyclohexylene.

Preferred specific examples of formula [S1] include structures of formulas [S1-x1] to [S1-x7] below.

In the formulas [S1-x1] to [S1-x7], R ¹ is an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkoxyalkyl group having 2 to 20 carbon atoms. X ^p is -(CH ₂ ) _a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-. A ₁ is an oxygen atom or -COO-* (the bond marked with * bonds with (CH ₂ ) _a2 ), and A ₂ is an oxygen atom or *-COO- (however, the "*" is replaced with The attached bond is (CH ₂ ) bonded to _a2 ). a ₁ and a ₃ are independently integers of 0 or 1, and a ₂ is an integer of 1 to 10. Cy is a 1,4-cyclohexylene group or a 1,4-phenylene group.

式［Ｓ２］中のＸ^３は、上記に定義したとおりである。なかでも、液晶配向性の観点から、－ＣＯＮＨ－、－ＮＨＣＯ－、－Ｏ－、－ＣＨ_２Ｏ－、－ＣＯＯ－又はＯＣＯ－が好ましい。
Ｒ^２は、上記に定義したとおりである。なかでも、液晶配向性の観点から、炭素数３～２０のアルキル又は炭素数２～２０のアルコキシアルキルが好ましい。
式［Ｓ２］の好ましい具体例として、－ＣＯＮＨ－（ＣＨ_２）_ｎ－ＣＨ_３（ｎ＝２～１７）、－ＮＨＣＯ－（ＣＨ_２）_ｎ－ＣＨ_３（ｎ＝２～１７）、－Ｏ－（ＣＨ_２）_ｎ－ＣＨ_３（ｎ＝２～１７）、－ＣＯＯ－（ＣＨ_２）_ｎ－ＣＨ_３（ｎ＝２～１７）、－ＣＨ_２Ｏ－（ＣＨ_２）_ｎ－ＣＨ_３（ｎ＝２～１７）が挙られる。

X ³ in formula [S2] is as defined above. Among them, from the viewpoint of liquid crystal orientation, -CONH-, -NHCO-, -O-, -CH ₂ O-, -COO- or OCO- are preferred.
R ² is as defined above. Among these, from the viewpoint of liquid crystal orientation, alkyl having 3 to 20 carbon atoms or alkoxyalkyl having 2 to 20 carbon atoms is preferred.
Preferred specific examples of formula [S2] include -CONH-(CH ₂ ) _n -CH ₃ (n=2 to 17), -NHCO-(CH ₂ ) _n -CH ₃ (n=2 to 17), -O -(CH ₂ ) _n -CH ₃ (n=2 to 17), -COO-(CH ₂ ) _n -CH ₃ (n=2 to 17), -CH ₂ O-(CH ₂ ) _n -CH ₃ ( n=2 to 17).

式［Ｓ３］中のＸ^４は、上記に定義したとおりである。なかでも、液晶配向性の観点から、－Ｏ－、－ＣＯＯ－又は－ＯＣＯ－が好ましい。
ステロイド骨格を有する構造として、β－シトステロールやエルゴステロール等の化合物からヒドロキシ基を除いた構造、日本特開平４－２８１４２７号の［００２４］に記載のステロイド化合物からヒドロキシ基を除いた構造、［００３０］に記載のステロイド化合物から酸クロライド基を除いた構造、［００３８］に記載のステロイド化合物からアミノ基を除いた構造、［００４２］にステロイド化合物からハロゲン基を除いた構造や、日本特開平８－１４６４２１の［００１８］～［００２２］に記載の構造が挙げられる。

X ⁴ in formula [S3] is as defined above. Among these, -O-, -COO-, or -OCO- is preferred from the viewpoint of liquid crystal orientation.
Structures having a steroid skeleton include a structure obtained by removing a hydroxy group from a compound such as β-sitosterol or ergosterol, a structure obtained by removing a hydroxy group from a steroid compound described in [0024] of Japanese Patent Application Publication No. 4-281427, and [0030 The structure obtained by removing the acid chloride group from the steroid compound described in ], the structure obtained by removing the amino group from the steroid compound described in [0038], the structure obtained by removing the halogen group from the steroid compound described in [0042], and the structure obtained by removing the halogen group from the steroid compound described in [0042], -146421, structures described in [0018] to [0022] can be mentioned.

（式中、＊は結合位置を示す）A preferred specific example of formula [S3] is the following formula [S3-x]. Furthermore, the definitions of X, Col, and G in formula [S3-x] are as follows.

(In the formula, * indicates the bonding position)

（式中、＊は結合位置を示す）More preferable structures of formula [S3] include structures represented by the following formulas [S3-1] to [S3-6].

(In the formula, * indicates the bonding position)

Examples of the structure having a tocopherol skeleton in formula [1] include structures derived from compounds such as α-tocopherol, β-tocopherol, γ-tocopherol, and δ-tocopherol. A specific example of a structure having a tocopherol skeleton includes a structure represented by the following formula [T]. Note that "*" indicates the bonding position.

The specific polymer contained in the liquid crystal aligning agent of the present invention is selected from the group consisting of a polyimide precursor having a divalent group represented by the above formula [1] and a polyimide that is an imidized product of the polyimide precursor. As long as it is at least one kind of polymer, it may be synthesized by any method.
Among these, the specific polymer is a tetracarboxylic dianhydride having the structure of the above formula [1] or a derivative thereof (hereinafter also referred to as a specific tetracarboxylic acid compound), or a tetracarboxylic acid dianhydride containing the specific tetracarboxylic acid compound. A polyimide precursor obtained by reacting an acid component and a diamine component; A polyimide which is an imidized product of the polyimide precursor; The above tetracarboxylic acid component and a diamine having the structure of formula [1] (hereinafter referred to as a specific diamine) ) or a diamine component containing a specific diamine; and a polyimide that is an imidized product of the polyimide precursor.

[Tetracarboxylic acid component]
The tetracarboxylic acid component used to synthesize the specific polymer contains either or both of the specific tetracarboxylic acid compound and other tetracarboxylic acid compounds.
<Specific tetracarboxylic acid compound>
The specific tetracarboxylic acid compound is a tetracarboxylic acid compound having the structure of the above formula [1], and includes, for example, a compound represented by the following formula [T] or a derivative thereof.

前記テトラカルボン酸化合物の誘導体としては、テトラカルボン酸二無水物、テトラカルボン酸ジハライド、テトラカルボン酸ジアルキルエステル又はテトラカルボン酸ジアルキルエステルジハライドが挙げられる。In formula [T], A represents a trivalent group, and two A's may be the same or different. Examples of A include a trivalent organic group having at least one member selected from the group consisting of a cyclobutane ring structure, a cyclopentane ring structure, a cyclohexane ring structure, a benzene ring structure, and the following formula (A-1). P represents a divalent organic group having the structure of formula [1].

Examples of the derivatives of the tetracarboxylic acid compound include tetracarboxylic dianhydride, tetracarboxylic dihalide, tetracarboxylic acid dialkyl ester, and tetracarboxylic acid dialkyl ester dihalide.

<Other tetracarboxylic acid compounds>
Other tetracarboxylic acid compounds include 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3, 3',4,4'-biphenyltetracarboxylic acid, 2,3,3',4-biphenyltetracarboxylic acid, bis(3,4-dicarboxyphenyl)ether, 3,3',4,4'-benzophenone Tetracarboxylic acid, bis(3,4-dicarboxyphenyl)sulfone, bis(3,4-dicarboxyphenyl)methane, 2,2-bis(3,4-dicarboxyphenyl)propane, 1,1,1, 3,3,3-hexafluoro-2,2-bis(3,4-dicarboxyphenyl)propane, bis(3,4-dicarboxyphenyl)dimethylsilane, bis(3,4-dicarboxyphenyl)diphenylsilane , 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis(3,4-dicarboxyphenyl)pyridine, 3,3',4,4'-diphenylsulfonetetracarboxylic acid, 3,4, Acid dianhydride obtained from tetracarboxylic acid such as 9,10-perylenetetracarboxylic acid or 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid, tetracarboxylic acid represented by the following formula [4] Examples include acid dianhydrides or derivatives thereof such as tetracarboxylic acid dihalide compounds, tetracarboxylic acid dialkyl ester compounds, or tetracarboxylic acid dialkyl ester dihalide compounds.

Among these, from the viewpoint of high solubility of the polymer, at least one type of tetracarboxylic dianhydride having a structure represented by formula [4] and its tetracarboxylic acid derivative is preferable.

（＊１は、一方の酸無水物基に結合する結合位置であり、＊２は、他方の酸無水物基に結合する結合位置である。）Z represents a structure selected from [4a] to [4k] below.

(*1 is the bonding position that is bonded to one acid anhydride group, and *2 is the bonding position that is bonded to the other acid anhydride group.)

（＊１、＊２は、上記に定義したとおりである。）In formula [4a], Z ¹ to Z ⁴ independently represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom, or a benzene ring. Preferred specific examples of Z ¹ to Z ⁴ include structures of the following formulas [4a-1] and [4a-2].

(*1 and *2 are as defined above.)

In formula [4g], Z ⁵ and Z ⁶ are independently a hydrogen atom or a methyl group.
Among Z in formula [4], from the viewpoint of ease of synthesis and ease of polymerization reactivity when producing a polymer, formula [4a], formula [4c] to formula [4g] or formula [ 4k] is preferred. Formula [4a] or formula [4e] to formula [4g] are more preferred, and [4a], formula [4e] or formula [4f] is particularly preferred. Preferred specific examples include tetracarboxylic dianhydrides or derivatives thereof having structures represented by [4a-1], formula [4a-2], formula [4e], and formula [4f].

The tetracarboxylic acid compound represented by formula [4] in the polymer of the present invention is preferably 1 mol % or more based on 100 mol % of all the tetracarboxylic acid compounds from the viewpoint of increasing the solubility of the polymer. Among these, 5 mol% or more is preferable, and 10 mol% or more is more preferable.
The tetracarboxylic acid compound is selected depending on the properties such as solubility of the polymer of the present invention in a solvent, coatability of a liquid crystal alignment agent, alignment of liquid crystal when used as a liquid crystal alignment film, voltage holding rate, and accumulated charge. It is also possible to use one type or a mixture of two or more types.

式［２］中のＸ、Ｙはそれぞれ、上記式［１］におけるのと同じ意味である。[Diamine component]
The diamine used to synthesize the specific polymer contains a specific diamine. The specific diamine is a diamine having the structure of the above formula [1], and includes, for example, a compound represented by the following formula [2].
<Specific diamine>
The specific diamine used in the liquid crystal aligning agent of the present invention is represented by the following formula [2].

X and Y in formula [2] each have the same meaning as in formula [1] above.

From the viewpoint of facilitating the synthesis of the specific diamine, X is preferably a single bond, -O-, -NH-, or -O-(CH ₂ ) _m -O-. m is an integer from 1 to 8.
In formula [2], Y may be at the meta position or ortho position from the position of X, but the ortho position is preferable from the viewpoint of high reactivity with the specific diamine. Specifically, formula [2] is preferably the following formula [2'].

The above formula [2] preferably has a structure of one of the following formulas from the viewpoint of high reactivity of the specific diamine, and more preferably a structure represented by formula [2]-a1-1.

As a preferable form of Y in the above formula [2], the preferable form of Y in the above formula [1] can be applied. Among them, structures selected from the above formulas [S1-x3] to [S1-x4], [S1-x6] and formula [S3-x] are preferable from the viewpoint of improving liquid crystal orientation, and preferred specific examples include structures selected from the following formula [S1-x4], [S1-x6] and [S3-x]. W-1] to [W-6].

In the formula, X ^p1 to X ^p8 are independently -(CH ₂ ) _a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH -, -O-, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-. X ^s1 to X ^s4 independently represent -O-, -COO- or -OCO-. X _a to X _f represent a single bond, -O-, -NH-, -O-(CH ₂ ) _m -O-. R ^1a to R ^1h independently represent an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an alkoxyalkyl group having 2 to 20 carbon atoms. m is an integer from 1 to 8.
The specific diamine is selected depending on the inkjet coating properties of the liquid crystal aligning agent, the liquid crystal alignment properties when used as a liquid crystal alignment film, the voltage holding characteristics, the accumulated charge, etc., and the response speed of the liquid crystal when used as a liquid crystal display element. It can be used as a species or as a mixture of two or more species.

The specific diamine is preferably used in an amount of 1 to 100 mol% of the diamine component used in the synthesis of the specific polymer, more preferably 2 to 100 mol%, particularly preferably 5 to 90 mol%.
As the diamine for synthesizing polyamic acid or polyamic acid ester, only the specific diamine may be used, or other diamines may be used in combination with the specific diamine. Here, other diamines include, for example, diamines having a pretilt angle development property other than the above (2), diamines having a function of polymerizing or generating radicals by light irradiation, and [0169 of WO (International Publication) 2015/046374] The diamine described in [0171] to [0172] having a carboxyl group or a hydroxyl group, the diamine having a nitrogen-containing heterocycle described in [0173] to [0188], and the diamine described in Japanese Patent Application Publication No. 2016-218149. Diamine having a nitrogen-containing structure described in [0050], 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(4-aminobutyl)- Examples include organosiloxane-containing diamines such as 1,1,3,3-tetramethyldisiloxane. Among these, in a PSA (Polymer Sustained Alignment) type liquid crystal display element, from the viewpoint of increasing the response speed, diamines having a function of polymerizing or generating radicals upon irradiation with light are preferred.

Preferred specific examples of other diamines include m-phenylenediamine, p-phenylenediamine, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-difluoro-4 , 4'-diaminodiphenyl, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylamine, N-methyl(4,4'-diaminodiphenyl)amine, 4,4'- Diaminobenzophenone, 1,4-diaminonaphthalene, 2,6-diaminonaphthalene, 1,2-bis(4-aminophenyl)ethane, 1,3-bis(4-aminophenyl)propane, 1,4-bis(4 -aminophenyl)butane, 1,4-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, 1,4-phenylenebis[(4-amino phenyl)methanone], 1,4-phenylenebis(4-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, N,N'-(1,4-phenylene)bis (4-aminobenzamide), N,N'-bis(4-aminophenyl)terephthalamide, N,N'-bis(4-aminophenyl)isophthalamide, 9,10-bis(4-aminophenyl)anthracene, 2,2'-bis[4-(4-aminophenoxy)phenyl]propane, 2,2'-bis(4-aminophenyl)propane, 1,3-bis(4-aminophenoxy)propane, 1,4- Bis(4-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,7-bis(4-aminophenoxy)heptane, 1 , 8-bis(4-aminophenoxy)octane, 1,9-bis(4-aminophenoxy)nonane, 1,10-(4-aminophenoxy)decane, bis(4-aminocyclohexyl)methane, 1,3- Diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4 , 4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 4,4'-diaminodiphenylethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3 '-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'- Dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenylethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenyl ether-3,3'-dicarboxylic acid acid, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4- aminophenyl)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, compounds represented by each of the following formulas (D-2-1) to (D-2-8),

更には、これらのアミノ基が２級のアミノ基であるジアミン化合物が挙げられる。

Further examples include diamine compounds in which these amino groups are secondary amino groups.

Examples of diamines having a pretilt angle development property other than the above formula (2) include diamines represented by the following structural formulas [V-1] to [V-7].

In the above formula, X ^v1 to X ^v4 are independently -(CH ₂ ) _a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, - Indicates NH-, -O-, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-. X ^v5 represents -O-, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-. X ^V6 to X ^V7 independently represent -O-, -COO- or -OCO-.
Examples of diamines having the function of polymerizing upon light irradiation include diamines in which structures represented by the following formulas [p1] to [p7] are bonded directly or via a linking group to an aromatic ring such as a benzene ring. It will be done.

式［Ｐ－ａ］、式［Ｐ－ｂ］における２つのアミノ基（－ＮＨ_２）の結合位置は限定されないが、ジアミンの反応性の観点から、２，４位の位置、２，５位の位置、又は３，５位の位置が好ましい。ジアミンを合成する際の容易性も加味すると、２，４位の位置、又は３，５位の位置がより好ましい。Specific examples include diamines represented by the following formula [P-a] or [P-b].

The bonding positions of the two amino groups (-NH ₂ ) in formula [P-a] and formula [P-b] are not limited, but from the viewpoint of the reactivity of the diamine, the positions of the 2 and 4 positions and the 2 and 5 positions are or the 3rd and 5th positions are preferred. Considering the ease of synthesizing the diamine, the 2nd and 4th positions or the 3rd and 5th positions are more preferable.

In formula [P-a], R ⁸ is a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )-, -CON(CH ₃ )-, or -N(CH ₃ )CO-, which is a single bond, -O-, -COO-, -NHCO-, or -CONH- for ease of synthesis. is preferable.
R ⁹ is a divalent group selected from a single bond, an alkylene group having 1 to 20 carbon atoms optionally substituted with a fluorine atom, an aromatic ring having 6 to 12 carbon atoms such as a benzene ring and a naphthalene ring, and cyclohexane. Divalent alicyclic groups having 3 to 8 carbon atoms such as rings, 5-membered or more rings such as pyrrole, imidazole, pyridine, pyrimidine, pyrazine, pyridazine, triazine, indole, quinoline, carbazole, thiazole, purine, tetrahydrofuran, thiophene, etc. represents a divalent cyclic group selected from heterocycles. Here, -CH ₂ - of the alkylene group may be optionally substituted with -CF ₂ - or -CH=CH-. From the viewpoint of ease of synthesis, a single bond or an alkylene group having 1 to 12 carbon atoms is preferred. k is an integer from 0 to 4.

R ¹⁰ represents a structure selected from the above formulas [p1] to [p7]. From the viewpoint of photoreactivity, [p1], [p2], and [p4] are preferable.
In formula [P-b], Y ₁ and Y ₃ are independently -CH ₂ -, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO - represents. Y ₂ and Y ₅ independently have the same meaning as R ₉ in [Pa] above. Y ₄ represents a cinnamoyl group. Y ₆ represents a structure selected from the above formulas [p1] to [p7]. From the viewpoint of photoreactivity, [p1], [p2], and [p4] are preferable. m represents 0 or 1.
Diamine, which has the ability to polymerize when exposed to light, is used depending on the characteristics such as liquid crystal orientation, pretilt angle, voltage holding characteristics, and accumulated charge when used as a liquid crystal alignment film, and the response speed of liquid crystal when used as a liquid crystal display element. , can be used alone or in combination of two or more.

The diamine having the function of polymerizing upon light irradiation is preferably used in an amount of 10 to 70 mol% of the diamine component used in the synthesis of the specific polymer, more preferably 10 to 60 mol%, particularly preferably 10 to 50 mol%. be.
Examples of diamines that have the function of generating radicals when irradiated with light include diamines that have a moiety in the side chain that has a radical-generating structure that decomposes and generates radicals when irradiated with ultraviolet light, such as diamines represented by the following formula (R). can be mentioned.

Ar, R ₁ , R ₂ , T ₁ , T ₂ , S and Q in the above formula (R) have the following definitions.
That is, Ar represents an aromatic hydrocarbon group selected from phenylene, naphthylene, and biphenylene, which may be substituted with an organic group, and the hydrogen atom may be substituted with a halogen atom.
R ₁ and R ₂ are independently an alkyl group or an alkoxy group having 1 to 10 carbon atoms.
T ₁ and T ₂ are independently a single bond or -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N(CH ₃ )- , -CON(CH ₃ )-, -N(CH ₃ )CO-.
S has the same meaning as R ⁹ in [Pa] above.

（式中、＊は結合位置を示す。）
上記式（Ｒ）において、カルボニルが結合しているＡｒは紫外線の吸収を効率的にする観点から、ナフチレン、ビフェニレンなどの共役長の長い構造が好ましい。また、Ａｒには置換基を有していても良く、かかる置換基は、アルキル基、ヒドロキシル基、アルコキシ基、アミノ基などのような電子供与性の有機基が好ましい。紫外線の波長が２５０～３８０ｎｍの範囲であればフェニル基でも十分な特性が得られるため、フェニル基が最も好ましい。Q is a structure selected from the following formulas [q-1] to [q-4] (in the structural formula, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ is -CH ₂ -, - NR-, -O-, or -S-).

(In the formula, * indicates the bonding position.)
In the above formula (R), Ar to which carbonyl is bonded preferably has a structure with a long conjugation length, such as naphthylene or biphenylene, from the viewpoint of efficient absorption of ultraviolet rays. Further, Ar may have a substituent, and the substituent is preferably an electron-donating organic group such as an alkyl group, a hydroxyl group, an alkoxy group, or an amino group. A phenyl group is most preferred because sufficient properties can be obtained with a phenyl group if the wavelength of ultraviolet rays is in the range of 250 to 380 nm.

Furthermore, R ₁ and R ₂ are independently an alkyl group, an alkoxy group, a benzyl group, or a phenethyl group having 1 to 10 carbon atoms, and in the case of an alkyl group or an alkoxy group, R ₁ and R ₂ form a ring. You may do so.
Q is more preferably a hydroxyl group or an alkoxyl group from the viewpoint of easy production of the specific polymer.
Diaminobenzene in formula (R) may have any structure of o-phenylenediamine, m-phenylenediamine, or p-phenylenediamine, but in terms of its high reactivity with the tetracarboxylic acid component, m-phenylenediamine, Or p-phenylenediamine is preferred.

Specifically, structures represented by the following formulas [R-1] to [R-4] are most preferred in terms of ease of synthesis, high versatility, properties, etc. Note that in the formula, n is an integer from 2 to 8.

The diamine having the function of generating radicals upon light irradiation is preferably used in an amount of 5 to 70 mol% of the diamine component used in the synthesis of the specific polymer, and more preferably 10 to 60 mol% from the viewpoint of maintaining liquid crystal orientation. and particularly preferably 10 to 50 mol%.

<Synthesis of specific polymer>
The specific polymer is obtained by reacting a diamine and a tetracarboxylic acid compound as described above. Examples of the method for obtaining polyamic acid include a method for obtaining polyamic acid by polycondensing a tetracarboxylic dianhydride and a diamine, or a method for obtaining polyamic acid by polycondensing a tetracarboxylic acid dihalide compound and a diamine compound. .
The specific polymer can be obtained by reacting it with a molecular weight regulator, if necessary. Examples of molecular weight modifiers include acid monoanhydrides such as maleic anhydride, phthalic anhydride, and itaconic anhydride, monoamine compounds such as aniline, cyclohexylamine, and n-butylamine, and monoisocyanate compounds such as phenyl isocyanate and naphthylisocyanate. Can be mentioned. The proportion of the molecular weight regulator used is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, based on the total of 100 parts by mass of the tetracarboxylic acid compound and diamine used.

Methods for obtaining polyamic acid esters include a method of polycondensing a tetracarboxylic acid dialkyl ester compound in which a carboxylic acid group is dialkyl esterified and a diamine, and a tetracarboxylic acid dialkyl ester dihalide in which a carboxylic acid group is dialkyl esterified and dihalidated. Examples include a method of polycondensing a compound and a primary or secondary diamine, or a method of converting a carboxyl group of a polyamic acid into an ester.
Examples of methods for obtaining polyimide include the method of ring-closing the polyimide precursor described above to obtain polyimide.

The reaction between the diamine and the tetracarboxylic acid compound is preferably carried out in a solvent. The solvent is not particularly limited as long as it dissolves the produced polymer. Specific examples of the solvent are listed below, but the solvent is not limited to these examples.
For example, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethylsulfoxide or 1,3-dimethyl-2-imidazolidinone. can be mentioned. If the polymer has high solvent solubility, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone or the following formulas [D-1] to [D-3] may be used. Any solvent can be used.

（式［Ｄ－１］中、Ｄ^１は炭素数１～３のアルキレン基を示し、式［Ｄ－２］中、Ｄ^２は炭素数１～３のアルキレン基を示し、式［Ｄ－３］中、Ｄ^３は炭素数１～４のアルキレン基を示す）。
これら溶媒は単独で使用しても、混合して使用してもよい。更に、重合体を溶解させない溶媒であっても、生成した重合体が析出しない範囲で、前記溶媒に混合して使用してもよい。また、溶媒中の水分は重合反応を阻害し、更には生成した重合体を加水分解させる原因となるので、溶媒は脱水乾燥させたものを用いることが好ましい。

(In the formula [D-1], D ¹ represents an alkylene group having 1 to 3 carbon atoms, and in the formula [D-2], D ² represents an alkylene group having 1 to 3 carbon atoms, and the formula [D-3 ], D ³ represents an alkylene group having 1 to 4 carbon atoms).
These solvents may be used alone or in combination. Furthermore, even if the solvent does not dissolve the polymer, it may be used by mixing it with the above-mentioned solvent as long as the produced polymer does not precipitate. Further, since water in the solvent inhibits the polymerization reaction and further causes hydrolysis of the produced polymer, it is preferable to use a solvent that has been dehydrated and dried.

When reacting a diamine and a tetracarboxylic acid compound in a solvent, the reaction can be carried out at any concentration, but if the concentration is too low, it will be difficult to obtain a high molecular weight polymer; The viscosity of the reaction solution becomes too high, making uniform stirring difficult. Therefore, it is preferably 1 to 50% by weight, more preferably 5 to 30% by weight. The initial stage of the reaction can be carried out at a high concentration, and then the solvent can be added.
In the polycondensation reaction, the ratio of the total number of moles of diamine to the total number of moles of tetracarboxylic acid compound is preferably 0.8 to 1.2. As in normal polycondensation reactions, the closer this molar ratio is to 1.0, the greater the molecular weight of the specific polymer produced.
Polyimide is a polyimide obtained by ring-closing the polyimide precursor, and in this polyimide, the ring-closing rate (also referred to as imidization rate) of amic acid groups does not necessarily have to be 100%, and may vary depending on the use and purpose. Can be adjusted arbitrarily.

Examples of methods for imidizing the polyimide precursor include thermal imidization, in which the polyimide precursor solution is directly heated, and catalytic imidization, in which a catalyst is added to the polyimide precursor solution.
The temperature when thermally imidizing the polyimide precursor in a solution is 100 to 400°C, preferably 120 to 250°C, and it is preferable to carry out the process while removing water produced by the imidization reaction from the system.
Catalytic imidization of the polyimide precursor can be carried out by adding a basic catalyst and an acid anhydride to a solution of the polyimide precursor and stirring at -20°C to 250°C, preferably 0 to 180°C. . The amount of the basic catalyst is 0.5 to 30 times the mole of the amic acid group, preferably 2 to 20 times the mole, and the amount of the acid anhydride is 1 to 50 times the mole of the amic acid group, preferably 3 to 30 times the mole. It's double. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, etc. Among them, pyridine is preferred because it has an appropriate basicity to allow the reaction to proceed. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Among them, acetic anhydride is preferably used because it facilitates purification after the reaction is completed. The imidization rate by catalytic imidization can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

When recovering the generated polyimide precursor or polyimide from the polyimide precursor or polyimide reaction solution, the reaction solution may be poured into a solvent and precipitated. Examples of the solvent used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, water, and the like. The polymer precipitated in a solvent can be collected by filtration, and then dried under normal pressure or reduced pressure, at room temperature, or by heating. Furthermore, by repeating the procedure of redissolving the precipitated and recovered polymer in a solvent and re-precipitating and recovering it 2 to 10 times, impurities in the polymer can be reduced. Examples of the solvent in this case include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more types of solvents selected from these, since the efficiency of purification will further increase.

The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) of the polyimide precursor and polyimide is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. It is. Further, the molecular weight distribution (Mw/Mn) expressed as the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC is preferably 15 or less, more preferably 10 or less. By having a molecular weight within such a range, good alignment of the liquid crystal display element can be ensured.

<Liquid crystal alignment agent>
The liquid crystal aligning agent of the present invention is constituted by dissolving in a solvent at least one polymer selected from the group consisting of polyimide precursors and polyimides as described above, and optional additive components used as necessary. .
The solvent used in the liquid crystal aligning agent of the present invention includes at least one solvent A selected from the group consisting of formulas (d-1) to (d-5) and (e), and the formula ( At least one solvent B selected from the group consisting of B-1) to (B-3).
By containing the solvent A, the specific polymer is easily dissolved in the solvent, and a liquid crystal aligning agent with excellent filterability and printability can be obtained. In addition, by containing the solvent B, pinholes and repelling are suppressed when the liquid crystal aligning agent is applied to the substrate, so a liquid crystal aligning agent with excellent printability can be obtained. In addition, by containing a combination of solvent A and solvent B, when the coating film of the liquid crystal aligning agent is dried, aggregation does not occur between the side chain components of the specific polymer, so that the in-plane uniformity of the alignment component is improved. is increased, and a liquid crystal alignment film having excellent liquid crystal alignment properties can be obtained. Moreover, even if the specific polymer contains a plurality of types of monomer components by combining two or more types, a liquid crystal alignment agent with excellent filterability and printability and a liquid crystal alignment film with excellent liquid crystal alignment properties can be obtained.

From the viewpoint of further improving printability, the solvent preferably contains three or more kinds of solvents A and one or more solvents B, more preferably contains four or more kinds, and 5 It is particularly preferable to contain more than one species.
In formula (d-1), the monovalent hydrocarbon group having 1 to 8 carbon atoms for R _1a includes a chain hydrocarbon group and an alicyclic hydrocarbon group, such as a chain hydrocarbon group having 1 to 8 carbon atoms. Examples include alkyl groups and cycloalkyl groups having 3 to 8 carbon atoms. Examples of the monovalent group having "--O--" between the carbon-carbon bonds in the hydrocarbon group include, for example, an alkoxyalkyl group having 2 to 8 carbon atoms.
Specific examples of these include chain alkyl groups having 1 to 8 carbon atoms, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, and octyl groups. Examples of the cycloalkyl group having 3 to 8 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, and a cyclohexyl group. Examples of the alkoxyalkyl group having 2 to 8 carbon atoms include methoxymethyl group, methoxyethyl group, methoxypropyl group, methoxybutyl group, ethoxymethyl group, and ethoxyethyl group. These groups may be linear or branched.

In formulas (d-2), (d-5) and formula (e), examples of the alkyl group having 1 to 6 carbon atoms in R _2a , R _2b , R _5a , r _1a and r _1b include methyl group, ethyl group, etc. group, propyl group, butyl group, pentyl group, hexyl group, etc., and these may be linear or branched.
In formula (d-3), R _3a represents a methyl group or an ethyl group.
In formula (d-5), the monovalent hydrocarbon group having 1 to 6 carbon atoms for R _5b and R _5c includes a chain hydrocarbon group and an alicyclic hydrocarbon group, for example, a monovalent hydrocarbon group having 1 to 6 carbon atoms. Examples include a chain alkyl group, a cycloalkyl group having 3 to 6 carbon atoms, and the like. Further, examples of the monovalent group having "-O-" between carbon-carbon bonds in the hydrocarbon group include, for example, an alkoxyalkyl group having 1 to 6 carbon atoms. Specific examples of these include chain alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl, hexyl, etc.; cycloalkyl groups having 3 to 6 carbon atoms; , cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, etc.

Specific examples of formula (d-1) include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N- (n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-(n-hexyl)-2-pyrrolidone, N-cyclohexyl- Examples include 2-pyrrolidone, N-(n-octyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, and N-methoxybutyl-2-pyrrolidone. Among these, N-ethyl-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-(t-butyl)-2-pyrrolidone, N-(n Particularly preferred are -butyl)-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N-(n-hexyl)-2-pyrrolidone, and N-methoxypropyl-2-pyrrolidone.

Specific examples of formula (d-2) include 1,3-dimethyl-2-imidazolidinone (hereinafter referred to as the symbol DMI), 1,3-diethyl-2-imidazolidinone, and 1,3-dimethyl-2-imidazolidinone. Examples include dipropyl-2-imidazolidinone and 1,3-diisopropyl-2-imidazolidinone. DMI is preferred from the viewpoint of improving the filterability of the liquid crystal aligning agent.
Specific examples of formula (d-5) include 3-butoxy-N,N-dimethylpropanamide, 3-methoxy-N,N-dimethylpropanamide, 3-hexyloxy-N,N-dimethylpropanamide, iso Examples include propoxy-N-isopropyl-propionamide and n-butoxy-N-isopropyl-propionamide. Among these, 3-butoxy-N,N-dimethylpropanamide or 3-methoxy-N,N-dimethylpropanamide is preferred from the viewpoint of improving the filterability of the liquid crystal aligning agent.

Specific examples of formula (e) include ethylene carbonate, propylene carbonate, butylene carbonate, pentylene carbonate, hexylene carbonate, 2-methyl-1,3-propylene carbonate, and 2,2-dimethyl-1,3-propylene carbonate. Examples include. Among these, propylene carbonate, ethylene carbonate, or butylene carbonate is preferred from the viewpoint of improving the filterability of the liquid crystal aligning agent.
Among solvent A, from the viewpoint of improving liquid crystal orientation and filterability, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-cyclohexyl-2 -Pyrrolidone, N-(n-hexyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, γ-butyrolactone, γ-valerolactone, γ-hexanolactone , 3-butoxy-N,N-dimethylpropanamide, and 3-methoxy-N,N-dimethylpropanamide.

From the viewpoint of improving filterability, the content ratio of solvent A in the solvent is preferably 5 to 99% by mass, more preferably 10 to 90% by mass, and 20 to 90% by mass, based on the entire solvent contained in the liquid crystal aligning agent. % is more preferable.
As the alkyl group of A _p1 and A _p2 of the above formula (B-1), the alkyl group of A _p3 and A _p4 of the above formula (B-2), and the alkyl group of A _p5 of the above formula (B-4), , a linear alkyl group having 1 to 6 carbon atoms, a branched alkyl group having 3 to 6 carbon atoms, and the like.
The alkanediyl groups of A _k1 , A _k2 , and A _k6 may be linear or branched, and are, for example, methylene group, ethylene group, 1,3-propanediyl group, 1,2-propanediyl group, 1,4- Examples include butanediyl group, 1,3-butanediyl group, and the like. A _k1 is preferably an ethylene group, a 1,3-propanediyl group or a 1,4-butanediyl group. It is preferable that n is 1 or 2. Examples of the alkyl groups of A _k4 and A _k5 in the above formula (B-3) include linear alkyl groups having 1 to 4 carbon atoms, branched alkyl groups having 3 to 4 carbon atoms, and the like.

Preferred compounds represented by the above formula (B-1) include, for example, ethylene glycol dimethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol ethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, Diethylene glycol diethyl ether, diethylene glycol ethyl propyl ether, diethylene glycol propyl methyl ether, diethylene glycol butyl methyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, dipropylene glycol dimethyl ether, propylene glycol diacetate, ethylene glycol, 1,4-butanediol, etc. can be mentioned.

Examples of the compound represented by the above formula (B-2) include methyl glycolate, ethyl glycolate, butyl glycolate, ethyl lactate, n-butyl lactate, isoamyl lactate, and ethyl-3-ethoxypropionate. .
Examples of the compound represented by the above formula (B-3) include diacetone alcohol, acetylacetone, ethyl acetoacetate, diisobutyl ketone, 4,6-dimethyl-2-heptanone, diisobutylcarbinol, and the like.
Examples of the compound represented by the above formula (B-4) include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether. Examples include ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, and the like.

Among solvent B, from the viewpoint of achieving both printability and filterability, diisobutylketone, diisobutylcarbinol, 4,6-dimethyl-2-heptanone, diacetone alcohol, n-butyl lactate, isoamyl lactate, butyl glycolate, Ethyl-3-ethoxypropionate, ethylene glycol monobutyl ether, propylene glycol monobutyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl propyl ether, diethylene glycol propyl methyl ether, diethylene glycol butyl methyl ether, dipropylene glycol monomethyl ether, Preferably, it is at least one selected from propylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, and propylene glycol diacetate.
The content of the solvent B in the solvent is preferably 1 to 95% by mass, more preferably 10 to 90% by mass, and even more preferably 20 to 90% by mass, based on the entire solvent contained in the liquid crystal aligning agent.

The solvent contained in the liquid crystal aligning agent of the present invention preferably contains one kind of combination selected from the following ms1 to ms10, from the viewpoint of achieving both printability and filterability of the liquid crystal aligning agent, and from MS1 to MS29. It is more preferable to include one selected combination.
・ms1: N-methyl-2-pyrrolidone and propylene glycol monobutyl ether ・ms2: N-methyl-2-pyrrolidone and dipropylene glycol monomethyl ether ・ms3: N-methyl-2-pyrrolidone and dipropylene glycol dimethyl ether ・ms4: N -Methyl-2-pyrrolidone and propylene glycol monomethyl ether ・ms5: N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether ・ms6: N-ethyl-2-pyrrolidone and dipropylene glycol monomethyl ether ・ms7: N-ethyl-2 -Pyrrolidone and dipropylene glycol dimethyl ether・ms8: N-ethyl-2-pyrrolidone and propylene glycol monomethyl ether・ms9: N-methyl-2-pyrrolidone and isoamyl lactate・ms10: N-methyl-2-pyrrolidone and diacetone alcohol・ms11: γ-butyrolactone and ethyl-3-ethoxypropionate ms12: N-ethyl-2-pyrrolidone and diisobutyl ketone

・MS1: N-methyl-2-pyrrolidone, γ-butyrolactone, and propylene glycol monobutyl ether ・MS2: N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol monomethyl ether ・MS3: N-methyl-2-pyrrolidone and γ-Butyrolactone and dipropylene glycol dimethyl ether MS4: N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monomethyl ether MS5: N-ethyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether MS6: N - Ethyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol monomethyl ether ・MS7: N-ethyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether ・MS8: N-ethyl-2-pyrrolidone, γ-butyrolactone, and Propylene glycol monomethyl ether

・MS9: N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, and propylene glycol monobutyl ether ・MS10: N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, and dipropylene glycol monomethyl ether ・MS11: N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, and dipropylene glycol dimethyl ether, MS12: N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, γ-butyrolactone, and propylene glycol monomethyl ether, MS13: N-methyl-2-pyrrolidone, diacetone alcohol, and diethylene glycol diethyl ether ・MS14: N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol monomethyl ether ・MS15: N-methyl-2-pyrrolidone and N-ethyl -2-pyrrolidone and diisobutyl carbinol MS16: N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether and diisobutyl ketone

・MS17: N-ethyl-2-pyrrolidone, ethylene glycol monobutyl ether acetate, and dipropylene glycol monomethyl ether ・MS18: N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, and diacetone alcohol ・MS19: γ-butyrolactone and 1,3-dimethyl-2-imidazolidinone and ethyl-3-ethoxypropionate MS20: N-methyl-2-pyrrolidone and 3-methoxy-N,N-dimethylpropanamide and diacetone alcohol MS21: N-Methyl-2-pyrrolidone, propylene carbonate, and diacetone alcohol MS22: N-methyl-2-pyrrolidone, butyl glycolate, and dipropylene glycol dimethyl ether

・MS23: N-ethyl-2-pyrrolidone, diacetone alcohol, and propylene glycol monobutyl ether ・MS24: N-ethyl-2-pyrrolidone, diacetone alcohol, and ethyl-3-ethoxypropionate ・MS25: γ-valerolactone γ-Butyrolactone and ethyl-3-ethoxypropionate MS26: N-methyl-2-pyrrolidone and diethylene glycol diethyl ether and dipropylene glycol monomethyl ether MS27: N-methyl-2-pyrrolidone and propylene glycol monobutyl ether and diethylene glycol butyl Methyl ether/MS28: N-ethyl-2-pyrrolidone, diethylene glycol ethyl methyl ether, and diisobutyl ketone/MS29: N-methyl-2-pyrrolidone, diacetone alcohol, and propylene glycol diacetate

In the liquid crystal aligning agent of the present invention, other solvents may be used in combination with the above solvents. Other solvents that can be used here include, for example, N,N-dimethylpropylene urea, N,N,2-trimethylpropionamide, ethylene glycol monobutyl ether (butyl cellosolve), methylmethoxypropionate, isoamylpropionamide, ester, isoamyl isobutyrate, diisopentyl ether, cyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, methyl 2-hydroxyisobutyrate, and solvents with low surface tension described in [0203] of WO2011/132751. However, it is not limited to these.

The solid content concentration (ratio of the total weight of components other than the solvent in the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) in the liquid crystal aligning agent of the present invention is selected in consideration of viscosity, volatility, etc. However, the particularly preferable solid content concentration range varies depending on the method used when applying the liquid crystal aligning agent to the substrate. For example, in the case of flexographic printing, it is particularly preferable that the solid content concentration be in the range of 3 to 9% by weight, and thereby the solution viscosity be in the range of 12 to 50 mPa·s. In the case of the inkjet method, it is particularly preferable that the solid content concentration is in the range of 1 to 5% by weight, and thereby the solution viscosity is in the range of 3 to 15 mPa·s.
The liquid crystal aligning agent of the present invention includes a crosslinkable compound having an epoxy group, an isocyanate group, an oxetane group, or a cyclocarbonate group, a crosslinkable compound having at least one substituent selected from a hydroxyl group, a hydroxyalkyl group, and a lower alkoxyalkyl group. A crosslinking compound having a polymerizable unsaturated bond or a crosslinking compound having a polymerizable unsaturated bond may be introduced. It is preferable that the crosslinkable compound has two or more of these substituents and polymerizable unsaturated bonds.

Examples of the crosslinkable compound having an epoxy group or an isocyanate group include the compounds described in [0087] of WO2015/008846.
Specific examples of the crosslinkable compound having an oxetane group include crosslinkable compounds represented by formulas [4a] to [4k] listed on pages 58 to 59 of WO2011/132751. More preferable specific examples include compounds of formula [4b], formula [4d], and formula [4k] where n=5.
Specific examples of crosslinkable compounds having a cyclocarbonate group include crosslinkable compounds represented by formulas [5-1] to [5-42] listed on pages 76 to 82 of WO2012/014898. .

Examples of the crosslinkable compound having at least one substituent selected from the group consisting of a hydroxyl group and an alkoxyl group include the compounds described in [0090] to [0092] of WO2015/008846, and the compounds described in [0054] of WO2015/072554. Examples include a compound having a hydroxyalkylamide group, a compound described in [0126] of WO2015/156314, and the like. More preferable specific examples include crosslinkable compounds represented by formulas [6-1] to [6-48] listed in [181] to [185] of WO2011/132751, and those listed in [0054] of WO2015/072554. Examples include compounds having a hydroxyalkylamide group, and compounds described in [0126] of WO2015/156314.
Examples of the crosslinkable compound having a polymerizable unsaturated bond include the compounds described in [0186] of WO2011/132751.

In addition, a compound represented by formula [5] described in [0188] of WO2011/132751 can also be used.
The above compounds are examples of crosslinkable compounds, and the present invention is not limited thereto. Moreover, the number of the crosslinkable compounds used for the liquid crystal aligning agent of this invention may be one type, and may combine two or more types.
The content of the crosslinkable compound in the liquid crystal aligning agent of the present invention is preferably 0.1 to 150 parts by mass based on 100 parts by mass of all polymer components. Among these, in order for the crosslinking reaction to proceed and to exhibit the desired effect, the amount is preferably 0.1 to 100 parts by weight based on 100 parts by weight of all polymer components. More preferred is 1 part by mass to 50 parts by mass.

For the liquid crystal aligning agent of the present invention, a compound that improves the uniformity of the film thickness and surface smoothness of the liquid crystal aligning film when the liquid crystal aligning agent is applied can be used.
Examples of compounds that improve the uniformity of film thickness and surface smoothness of the liquid crystal alignment film include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants. More specifically, for example, FTOP EF301, EF303, EF352 (all manufactured by Tochem Products), Megafac F171, F173, R-30 (all manufactured by Dainippon Ink), Florado FC430, FC431 (all manufactured by Dainippon Ink), , manufactured by Sumitomo 3M), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, and SC106 (all manufactured by Asahi Glass).
The proportion of these surfactants used is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass, based on 100 parts by mass of all polymer components contained in the liquid crystal aligning agent. be.

Furthermore, the liquid crystal alignment agent of the present invention includes compounds that promote charge transfer in the liquid crystal alignment film and promote charge loss in the device, as published on pages 69 to 73 of WO2011/132751 (published on October 27, 2011). It is also possible to add nitrogen-containing heterocyclic amine compounds represented by formulas [M1] to [M156]. This amine compound may be added directly to the liquid crystal aligning agent, but it is preferable to add it after making it into a solution with a concentration of 0.1 to 10% by mass, preferably 1 to 7% by mass, in an appropriate solvent. This solvent is not particularly limited as long as it can dissolve the above-mentioned specific polymer.
In addition to the above-mentioned poor solvent, crosslinkable compound, compound that improves the uniformity of the film thickness and surface smoothness of the resin coating or liquid crystal alignment film, and the compound that promotes charge loss, the liquid crystal aligning agent of the present invention includes the liquid crystal aligning agent. A dielectric or conductive substance may be added for the purpose of changing the electrical properties such as dielectric constant and conductivity of the alignment film.

<Liquid crystal alignment film/liquid crystal display element>
The liquid crystal alignment agent of the present invention can be used as a liquid crystal alignment film by applying an alignment treatment on a substrate, baking it, and then subjecting it to alignment treatment by rubbing, light irradiation, or the like. Furthermore, in the case of vertical alignment applications, it can be used as a liquid crystal alignment film without alignment treatment. The substrate used in this case is not particularly limited as long as it is a highly transparent substrate, and in addition to glass substrates, plastic substrates such as acrylic substrates and polycarbonate substrates can also be used. From the viewpoint of process simplification, it is preferable to use a substrate on which ITO electrodes and the like for driving the liquid crystal are formed. Further, in a reflective liquid crystal display element, an opaque substrate such as a silicon wafer can be used as only one substrate, and in this case, a material that reflects light such as aluminum can also be used as the electrode.

Application methods for the liquid crystal aligning agent include screen printing, offset printing, flexo printing, inkjet method, dip method, roll coater method, slit coater method, spinner method, and spray method, but these methods improve the manufacturing efficiency of the liquid crystal aligning film. From this point of view, a coating method using flexographic printing or an inkjet method is preferable.
After the liquid crystal aligning agent is applied onto the substrate, the temperature is heated to 30 to 300°C, preferably 30°C, depending on the solvent used for the liquid crystal aligning agent, using a heating means such as a hot plate, a thermal circulation type oven, or an IR (infrared) type oven. A liquid crystal alignment film can be obtained by evaporating the solvent at a temperature of ~250°C. The thickness of the liquid crystal alignment film after firing is preferably 5 to 300 nm, more preferably 5 to 300 nm, because if it is too thick, it will be disadvantageous in terms of power consumption of the liquid crystal display element, and if it is too thin, the reliability of the liquid crystal display element may decrease. is 10 to 100 nm.

When the display mode of the liquid crystal display element to be manufactured is the VA type, the coating film formed as described above can be used as a liquid crystal alignment film as it is, but if necessary, it may be subjected to rubbing treatment or the following treatment. PSA processing may also be performed. On the other hand, if the display mode of the liquid crystal display element to be manufactured is a vertical electric field type other than VA type or a horizontal electric field type, the formed coating surface may be subjected to rubbing treatment or polarized ultraviolet irradiation. Orientation treatment is performed by processing.
The liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and has a liquid crystal composition containing a polymerizable compound that is polymerized by at least one of active energy rays and heat between the pair of substrates. It is also preferably used for liquid crystal display elements manufactured through a step of arranging objects and polymerizing a polymerizable compound by at least one of irradiation with active energy rays and heating while applying a voltage between electrodes. Here, the applied voltage can be, for example, 5 to 50 V direct current or alternating current. Moreover, ultraviolet rays are suitable as active energy rays. The ultraviolet rays include ultraviolet rays having a wavelength of 300 to 400 nm, preferably ultraviolet rays including light having a wavelength of 310 to 360 nm. The amount of light irradiation is preferably 0.1 to 20 J/cm ² , more preferably 1 to 20 J/cm ² .

The above liquid crystal display element controls the pretilt of liquid crystal molecules using the PSA method. In the PSA method, a small amount of a photopolymerizable compound, such as a photopolymerizable monomer, is mixed into the liquid crystal material, and after the liquid crystal cell is assembled, the photopolymerizable compound is exposed to ultraviolet light while a predetermined voltage is applied to the liquid crystal layer. The pretilt of liquid crystal molecules is controlled by the polymer produced. Since the alignment state of the liquid crystal molecules when the polymer is generated is memorized even after the voltage is removed, the pretilt of the liquid crystal molecules can be adjusted by controlling the electric field formed in the liquid crystal layer. Furthermore, since the PSA method does not require a rubbing process, it is suitable for forming a vertically aligned liquid crystal layer in which it is difficult to control pretilt by a rubbing process.

The liquid crystal display element of the present invention is obtained by obtaining a substrate with a liquid crystal alignment film from the liquid crystal aligning agent of the present invention by the method described above, and then producing a liquid crystal cell by a known method to obtain a liquid crystal display element.
The method for manufacturing a liquid crystal cell is to prepare a pair of substrates on which a liquid crystal alignment film is formed, sprinkle spacers on the liquid crystal alignment film of one substrate so that the liquid crystal alignment film surface is on the inside, and then close the other substrate. Examples include a method in which the substrates are bonded together and liquid crystal is injected under reduced pressure for sealing, or a method in which liquid crystal is dropped onto the surface of a liquid crystal alignment film on which spacers have been sprinkled, and then the substrates are bonded together and sealing is carried out.
The liquid crystal may be mixed with a polymerizable compound that is polymerized by ultraviolet irradiation or heat, as described above. Examples of polymerizable compounds include compounds having one or more polymerizable unsaturated groups such as acrylate groups and methacrylate groups in the molecule, such as polymerizable compounds represented by the following formulas (M-1) to (M-3). Examples include compounds.

The amount of the polymerizable compound is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the liquid crystal component. If the amount of the polymerizable compound is less than 0.01 part by mass, the polymerizable compound will not polymerize, making it impossible to control the alignment of the liquid crystal, and if it exceeds 10 parts by mass, there will be a large amount of unreacted polymerizable compound, which may cause problems in the liquid crystal display element. The burn-in characteristics are reduced. After producing the liquid crystal cell, the polymerizable compound is polymerized by irradiating heat or ultraviolet rays while applying an alternating current or direct current voltage to the liquid crystal cell. Thereby, the orientation of liquid crystal molecules can be controlled.
In addition, the liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and a polymerizable group that is polymerized by at least one of active energy rays and heat between the pair of substrates. It may also be used for a liquid crystal display element manufactured through a process of arranging a liquid crystal alignment film containing the above and applying a voltage between electrodes, that is, an SC-PVA mode. Here, ultraviolet rays are suitable as the active energy rays. As the ultraviolet rays, the ultraviolet rays used in the above-mentioned PSA method can be applied, including preferred embodiments. In the case of polymerization by heating, the heating temperature is 40 to 120°C, preferably 60 to 80°C. Moreover, the ultraviolet rays and heating may be performed simultaneously.

In order to obtain a liquid crystal alignment film containing a polymerizable group that is polymerized by at least one of active energy rays and heat, there is a method of adding a compound containing this polymerizable group to a liquid crystal aligning agent, a method of adding a compound containing this polymerizable group to a liquid crystal aligning agent, and a method of adding a polymer containing a polymerizable group. Examples include methods using components. Specific examples of polymers containing polymerizable groups include polymers obtained using the diamine that has the function of polymerizing upon irradiation with light.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.
(Specific diamine)
W-A1: Compound represented by formula [W-A1], W-A2: Compound represented by formula [W-A2] W-A3: Compound represented by formula [W-A3]

(Other side chain diamine compounds)
A1: Compound represented by formula [A1]

C1: Compound represented by formula [C1], C2: Compound represented by formula [C2] C3: Compound represented by formula [C3], C4: Compound represented by formula [C4]

(Tetracarboxylic acid compound)
D1: 1,2,3,4-cyclobutanetetracarboxylic dianhydride D2: Bicyclo[3,3,0]octane-2,4,6,8-tetracarboxylic dianhydride D3: Pyromellitic anhydride , D4: 2,3,5-tricarboxycyclopentyl acetic dianhydride

<Solvent A>
NMP: N-methyl-2-pyrrolidone, NEP: N-ethyl-2-pyrrolidone DMI: 1,3-dimethyl-2-imidazolidinone, GVL: γ-valerolactone GBL: γ-butyrolactone, CHP: N-cyclohexyl -2-pyrrolidone NHP: N-(n-hexyl)-2-pyrrolidone,
3MMP: 3-methoxy-N,N-dimethylpropanamide

<Solvent B>
IAL: Isoamyl lactate, nBL: n-butyl lactate, HBA: Butyl glycolate, EEP: Ethyl-3-ethoxypropionate, DIBC: Diisobutyl carbinol DIBK: Diisobutyl ketone, DAA: Diacetone alcohol BCA: Ethylene glycol monobutyl ether acetate PB: Propylene glycol monobutyl ether, PGDA: Propylene glycol diacetate PC: Propylene carbonate, DEME: Diethylene glycol methyl ethyl ether DEDE: Diethylene glycol diethyl ether DPM: Dipropylene glycol monomethyl ether DME: Dipropylene glycol dimethyl ether DEBM: Diethylene glycol butyl methyl ether

(molecular weight measurement)
The molecular weights of the polyimide precursor and polyimide were determined as follows using a room temperature gel permeation chromatography (GPC) device (GPC-101) (manufactured by Showa Denko) and columns (KD-803, KD-805) (manufactured by Shodex). It was measured as follows.
Column temperature: 50℃
Eluent: N,N'-dimethylformamide (as additives, 30 mmol/L (liter) of lithium bromide-hydrate (LiBr.H ₂ O), 30 mmol of phosphoric acid/anhydrous crystal (o-phosphoric acid) /L, tetrahydrofuran (THF) is 10ml/L), flow rate: 1.0ml/min Standard sample for creating a calibration curve: TSK standard polyethylene oxide (molecular weight: approximately 900,000, 150,000, 100,000 and 30,000 ) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight; approximately 12,000, 4,000, and 1,000) (manufactured by Polymer Laboratory Corporation).

(Measurement of imidization rate)
Put 20 mg of polyimide powder into an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube standard, φ5 (manufactured by Kusano Kagaku)), and add deuterated dimethyl sulfoxide (DMSO-d6, 0.05% by mass TMS (tetramethylsilane)). Mixed product) (0.53 ml) was added and completely dissolved by applying ultrasound. This solution was subjected to proton NMR measurement at 500 MHz using an NMR measuring device (JNW-ECA500) (manufactured by JEOL Datum). The imidization rate is determined by using a proton derived from a structure that does not change before and after imidization as a reference proton, and by calculating the peak integrated value of this proton and the proton peak derived from the NH group of amic acid that appears around 9.5 to 10.0 ppm. It was calculated using the following formula using the integrated value.
Imidization rate (%) = (1-α・x/y)×100
In the above formula, x is the integrated value of the proton peak derived from the NH group of amic acid, y is the integrated peak value of the reference proton, and α is one NH group proton of the amic acid in the case of polyamic acid (imidization rate is 0%) This is the ratio of the number of standard protons to the standard proton.

(viscosity)
The viscosity of the polyimide polymer was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL, a cone rotor TE-1 (1° 34', R24), and a temperature of 25°C. did.

<Synthesis of specific diamine>
W-A1 to W-A3 are new compounds that have not been published in literature, etc., and were synthesized as follows.
The products described in Synthesis Examples 1 to 3 below were identified by ¹ H-NMR analysis under the following conditions.
Equipment: Varian NMR System 400 NB (400 MHz).
Measurement solvent: CDCl _3, DMSO-d ₆ .
Reference substance: Tetramethylsilane (TMS) (δ0.0 ppm for ¹ H).

＜化合物［１］、［２］の合成＞
反応容器にテトラヒドロフラン（１６５．６ｇ）、４，４’－ジニトロ－１，１’－ビフェニル－２，２’-ジメタノール（４１．１ｇ、１３５ｍｍｏｌ）とトリエチルアミン（３１．５ｇ）を加え、窒素雰囲気氷冷条件にてメタンスルホニルクロリド（３３．２ｇ）を滴下し、１時間反応させることで化合物［１］を得た。続いて、テトラヒドロフラン（２４６．６ｇ）に溶解させたｐ－（ｔｒａｎｓ－４－ヘプチルシクロヘキシル）フェノール（７７．８ｇ）を加え、４０℃で１時間撹拌後、純水（２３３ｇ）に溶解させた水酸化カリウム（４１．０ｇ）を同温度にて加え、２１時間反応させた。反応終了後、１．０Ｍ塩酸水溶液（３１１ｍｌ）及び純水（１０５０ｇ）を加えて粗物を析出させ、ろ過により粗物を回収した。得られた粗物をテトラヒドロフラン（５７４ｇ）に５０℃加熱溶解させ、メタノール（３２８ｇ）を加えて結晶を析出させ、ろ過、乾燥することで化合物［２］を得た（収量：９７．９ｇ、収率：８９％）。<Synthesis Example 1 Synthesis of W-A1>

<Synthesis of compounds [1] and [2]>
Tetrahydrofuran (165.6 g), 4,4'-dinitro-1,1'-biphenyl-2,2'-dimethanol (41.1 g, 135 mmol) and triethylamine (31.5 g) were added to a reaction vessel, and the mixture was placed in a nitrogen atmosphere. Compound [1] was obtained by adding methanesulfonyl chloride (33.2 g) dropwise under ice-cooling conditions and reacting for 1 hour. Subsequently, p-(trans-4-heptylcyclohexyl)phenol (77.8 g) dissolved in tetrahydrofuran (246.6 g) was added, and after stirring at 40°C for 1 hour, water dissolved in pure water (233 g) was added. Potassium oxide (41.0 g) was added at the same temperature and reacted for 21 hours. After the reaction was completed, a 1.0 M aqueous hydrochloric acid solution (311 ml) and pure water (1050 g) were added to precipitate a crude substance, and the crude substance was collected by filtration. The obtained crude product was dissolved in tetrahydrofuran (574 g) by heating at 50°C, methanol (328 g) was added to precipitate crystals, and the compound [2] was obtained by filtering and drying (yield: 97.9 g, rate: 89%).

¹ H-NMR (400MHz) in CDCl ₃ : 0.87-0.90ppm (m, 6H), 0.96-1.05ppm (m, 4H), 1.19-1.39ppm (m, 30H), 1.80-1.85ppm (m, 8H), 2.33-2.40ppm (m, 2H), 4.77ppm (s, 4H), 6.66-6.70ppm (m, 4H), 7. 02-7.06ppm (m, 4H), 7.40ppm (d, 2H, 8.4), 8.25ppm (dd, 2H, J=2.4Hz, J=8.4Hz), 8.54ppm (d , 2H, J=2.4Hz).

<Synthesis of W-A1>
Tetrahydrofuran (1783 g), compound [2] (74.3 g, 90.9 mmol), and 3% platinum carbon (5.94 g) were added to a reaction vessel, and the mixture was reacted in a hydrogen atmosphere at room temperature. After the reaction was completed, the reaction mixture was filtered, and the filtrate was concentrated under reduced pressure to give a total internal weight of 145 g. Subsequently, methanol (297 g) was added to the concentrated solution, stirred under ice cooling, filtered, and dried to obtain W-A1 (yield: 59.2 g, yield: 86%).
¹ H-NMR (400MHz) in CDCl ₃ : 0.87-0.90ppm (m, 6H), 0.96-1.05ppm (m, 4H), 1.19-1.40ppm (m, 30H), 1.81-1.84ppm (m, 8H), 2.32-2.38ppm (m, 2H), 3.67ppm (s, 4H), 4.69ppm (d, 2H, J=12.0Hz), 4.74ppm (d, 2H, J=11.6Hz), 6.62ppm (dd, 2H, J=2.4Hz, J=8.0Hz), 6.70-6.75ppm (m, 4H), 6 .91ppm (d, 2H, J=2.4Hz), 6.97-7.03ppm (m, 6H).

<Synthesis Example 2 Synthesis of W-A2>

<Synthesis of compound [3]>
In a reaction vessel, tetrahydrofuran (327.2 g), 4,4'-dinitro-2,2'-diphenic acid (40.9 g, 123 mmol) and p-(trans-4-heptylcyclohexyl)phenol (72.1 g), 4 -Dimethylaminopyridine (1.50 g) was added, and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (56.6 g) was added under nitrogen atmosphere and room temperature conditions, and the mixture was allowed to react for 3 hours. After the reaction was completed, the reaction solution was poured into pure water (1226 g) to precipitate a crude product, which was collected by filtration. Subsequently, the crude material was slurried washed with methanol (245 g), filtered, and the obtained crude material was dissolved in tetrahydrofuran (245 g) by heating at 60°C. After removing insoluble materials by filtration, the total internal weight was reduced to 232 g by vacuum concentration, and methanol (163 g) was added to precipitate crystals. After stirring under ice-cooling conditions, filtration and drying yielded compound [3]. (Yield: 73.9 g, yield: 71%).
¹ H-NMR (400MHz) in CDCl ₃ : 0.87-0.90ppm (m, 6H), 0.98-1.06ppm (m, 4H), 1.18-1.43ppm (m, 30H), 1.83-1.86ppm (m, 8H), 2.41-2.47ppm (m, 2H), 6.89-6.92ppm (m, 4H), 7.17-7.20ppm (m, 4H) ), 7.48ppm (d, 2H, 8.4), 8.49ppm (dd, 2H, J = 2.4Hz, J = 8.4Hz), 9.11ppm (d, 2H, J = 2.4Hz) ．．

<Synthesis of W-A2>
Tetrahydrofuran (443 g), methanol (73.9 g), compound [3] (73.9 g, 87.4 mmol), and 5% palladium on carbon (8.80 g) were added to a reaction vessel and reacted under hydrogen atmosphere at room temperature. After the reaction was completed, palladium on carbon was removed by filtration, and the total internal weight was reduced to 171 g by vacuum concentration. Subsequently, methanol (222 g) was added to the concentrated solution to precipitate crystals, followed by ice-cooling stirring, filtration, and drying to obtain W-A2 (yield: 66.6 g, yield: 97%).
¹ H-NMR (400MHz) in CDCl ₃ : 0.87-0.90ppm (m, 6H), 0.96-1.05ppm (m, 4H), 1.17-1.42ppm (m, 30H), 1.82-1.85ppm (m, 8H), 2.38-2.44ppm (m, 2H), 3.77ppm (s, 4H), 6.80-6.87ppm (m, 6H), 7. 08-7.13ppm (m, 6H), 7.41ppm (d, 2H, J=2.4Hz).

<Synthesis Example 3 Synthesis of W-A3>

<Synthesis of compounds [4] and [5]>
Toluene (366 g), 4-(trans-4-heptylcyclohexyl)-benzoic acid (73.1 g, 242 mmol) and N,N-dimethylformamide (0.73 g) were added to a reaction vessel, and the mixture was heated under nitrogen atmosphere at 50°C. Thionyl chloride (35.9 g) was added dropwise. After the dropwise addition, the reaction solution was reacted at the same temperature for 1 hour, and the reaction solution was concentrated under reduced pressure to obtain compound [4]. Subsequently, 4,4'-dinitro-1,1'-biphenyl-2,2'-dimethanol (35.0 g, 115 mmol) and triethylamine (26.8 g) were charged in tetrahydrofuran (210 g), and the mixture was placed on ice under a nitrogen atmosphere. Compound [4] dissolved in tetrahydrofuran (73.1 g) was added dropwise under cold conditions. After the dropwise addition was completed, the reaction temperature was raised to room temperature and the reaction was continued for 18 hours. After the reaction was completed, triethylamine hydrochloride was removed by filtration, and an oily compound was obtained by concentration under reduced pressure. The obtained oily compound was added to pure water (1015 g) to precipitate crystals, and the crude product was collected by filtration. Subsequently, the obtained crude product was slurried at room temperature with methanol (291 g), washed with ethyl acetate (175 g), filtered, and dried to obtain compound [5] (yield: 92.7 g, rate: 92%).
¹ H-NMR (400MHz) in CDCl ₃ : 0.89-0.91ppm (m, 6H), 0.99-1.09ppm (m, 4H), 1.20-1.47ppm (m, 30H), 1.85-1.88ppm (m, 8H), 2.46-2.52ppm (m, 2H), 5.14ppm (s, 4H), 7.23-7.26ppm (m, 4H), 7. 45ppm (d, 2H, J = 8.4Hz), 7.83-7.86ppm (m, 4H), 8.27ppm (dd, 2H, J = 2.4Hz, J = 8.4Hz), 8.47ppm (d, 2H, J=2.4Hz).

<Synthesis of W-A3>
Tetrahydrofuran (484 g), methanol (161 g), compound [5] (80.5 g, 92.2 mmol), and 3% platinum carbon (6.44 g) were added to a reaction vessel and reacted under hydrogen atmosphere at room temperature. After the reaction was completed, platinum carbon was removed by filtration, and the solvent was removed by vacuum concentration to give a total internal weight of 96.6 g. Subsequently, methanol (322 g) was added to the concentrated solution to precipitate crystals, followed by ice-cooling stirring and filtration to obtain a crude product. Subsequently, the obtained crude product was dissolved in ethyl acetate (322 g) by heating at 60°C, methanol (700 g) was added, crystals were precipitated under ice-cooling conditions, and W-A3 was obtained by filtering and drying. (Yield: 67.9 g, yield: 91%).
¹ H-NMR (400MHz) in CDCl ₃ : 0.87-0.91ppm (m, 6H), 0.98-1.08ppm (m, 4H), 1.19-1.47ppm (m, 30H), 1.84-1.87ppm (m, 8H), 2.44-2.51ppm (m, 2H), 3.71ppm (s, 4H), 5.02ppm (d, 2H, J=12.8Hz), 5.09ppm (d, 2H, J = 12.4Hz), 6.66ppm (dd, 2H, J = 2.4Hz, J = 8.0Hz), 6.84ppm (d, 2H, J = 2.4Hz) , 7.03ppm (d, 2H, J=8.0Hz), 7.19-7.25ppm (m, 4H), 7.89-7.92ppm (m, 4H).

<Synthesis of specific polymer>
[Synthesis example 1]
D2 (2.50 g, 10.0 mmol), W-A1 (3.03 g, 4.00 mmol), and C1 (1.73 g, 16.0 mmol) were added to NMP (18.1 g) and NEP (18.1 g). After dissolving in a mixed solvent and reacting at 60°C for 3 hours, D1 (1.78 g, 9.10 mmol) was added and reacted at 40°C for 3 hours to form a polyamic acid solution with a resin solid content of 20% by mass (viscosity :840 mPa·s) was obtained.
After adding NMP to the obtained polyamic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.43 g) and pyridine (1.37 g) were added as imidization catalysts, and the mixture was heated at 80°C. The reaction was allowed to proceed for 3 hours. This reaction solution was poured into methanol (382 ml), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder (PI-1). The imidization rate of this polyimide was 76.4%, the Mn was 16,165, and the Mw was 49,988.

[Synthesis example 2]
D2 (2.50 g, 10.0 mmol), W-A2 (3.14 g, 4.00 mmol), and C1 (1.84 g, 16.0 mmol) were added to NMP (11.1 g) and PC (25.8 g). After dissolving in a mixed solvent and reacting at 60°C for 3 hours, D1 (1.84 g, 9.38 mmol) was added and reacted at 40°C for 3 hours to obtain a polyamic acid solution with a resin solid content of 20% by mass (viscosity :658 mPa·s) was obtained.
After adding NMP to the obtained polyamic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.38 g) and pyridine (1.36 g) were added as an imidization catalyst, and the mixture was heated at 80°C. The reaction was allowed to proceed for 3 hours. This reaction solution was poured into methanol (382 ml), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder (PI-2). The imidization rate of this polyimide was 75.8%, the Mn was 15,430, and the Mw was 45,756.

[Synthesis example 3]
D2 (2.50 g, 10.0 mmol), W-A3 (3.25 g, 4.00 mmol), and C1 (1.73 g, 16.0 mmol) were mixed in GBL (37.3 g) and heated at 60 °C. After reacting for 3 hours, D1 (1.84 g, 9.38 mmol) was added and reacted at 40° C. for 3 hours to obtain a polyamic acid solution (viscosity: 656 mPa·s) with a resin solid content concentration of 20% by mass.
After adding GBL to the obtained polyamic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.32 g) and pyridine (1.34 g) were added as an imidization catalyst, and the mixture was heated at 80°C. The reaction was allowed to proceed for 3 hours. This reaction solution was poured into methanol (382 ml), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder (PI-3). The imidization rate of this polyimide was 74.7%, the Mn was 13,340, and the Mw was 41,948.

[Comparative synthesis example 1]
After adding A1 (0.63 g, 1.2 mmol), C4 (2.36 g, 21.8 mmol) and NMP to dissolve the diamine, D4 (4.12 g, 22.4 mmol) and NMP were added to give a set concentration of 20. It was expressed as mass%. After reacting at 60° C. for 3 hours, a polyamic acid solution (viscosity: 250 mPa·s) with a resin solid content concentration of 20% by mass was obtained.
After adding NMP to the obtained polyamic acid solution (20.0 g) and diluting it to 6.5% by mass, acetic anhydride (4.64 g) and pyridine (1.44 g) were added as imidization catalysts, and the mixture was heated at 80°C. The reaction was allowed to proceed for 3 hours. This reaction solution was poured into methanol (382 ml), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder (PI-R1). The imidization rate of this polyimide was 75%, Mn was 13,100, and Mw was 33,200.

[Comparative synthesis example 2]
Polyimide powder (PI-R2) was obtained in the same manner as in Polymer Comparative Synthesis Example 1, except that the type and composition of the diamine used were changed as shown in Table 1 below. The imidization rate of this polyimide was 55%, Mn was 10,500, and Mw was 20,900.

[Example 1]
NMP was added to the polyimide (PI-1) obtained in Polymer Synthesis Example 1 above until the polyimide amount was 12% by mass, and then stirred at 70° C. for 24 hours to dissolve it. Next, it was diluted with a mixed solution of NMP and PB to obtain a liquid crystal aligning agent (S-1) having a solid content concentration of 3% by mass and a solvent composition of NMP:PB=50:50 (mass ratio). This was subjected to the following evaluation of filterability, printability, and liquid crystal orientation.

<Evaluation of filterability>
The yield after filtering 100 ml of the liquid crystal aligning agent using a syringe filter (manufactured by Whatman) with a pore size of 0.2 μm and a diameter of 13 mm was measured, and the filterability was determined according to the following criteria.
(Evaluation criteria)
Excellent: The yield of the liquid crystal aligning agent is 40 ml or more. Good: The yield of the liquid crystal aligning agent is 5 ml or more and less than 40 ml. Not good: The yield of the liquid crystal aligning agent is less than 5 ml.

<Evaluation of printability>
The liquid crystal aligning agent obtained in the above filterability evaluation was applied onto the ITO surface of a 40 mm x 30 mm glass substrate with ITO electrodes (length: 40 mm, width: 30 mm, thickness: 1.1 mm) using an inkjet coating device HIS-200 ( (manufactured by Hitachi Plant Technologies) to prepare a coating film. The coating conditions at this time were a coating area of 70 mm x 70 mm, a nozzle pitch of 0.423 mm, a scan pitch of 0.5 mm, and a coating speed of 40 mm/sec. After being allowed to stand for 60 seconds after application, the filterability was evaluated according to the following criteria.
(Evaluation criteria)
Excellent: No pinholes or cissing observed.
Good: Either pinholes or cissing can be seen.
Not acceptable: Both pinholes and repellents are visible.

<Manufacture of liquid crystal cells>
After coating under the conditions described in the printability evaluation above, heat treatment was performed on a hot plate at 70°C for 90 seconds and in a thermal circulation clean oven at 230°C for 30 minutes, resulting in a film thickness of 80 nm. An ITO substrate with a liquid crystal alignment film was obtained. Two ITO substrates with the obtained liquid crystal alignment film were prepared, and bead spacers with a diameter of 4 μm (manufactured by JGC Catalysts & Chemicals Co., Ltd., Shinshu Ball, SW-D1) were applied to the liquid crystal alignment film surface of one of the substrates.
Next, a sealant (manufactured by Mitsui Chemicals, Inc., XN-1500T) was applied around the area. Next, the other substrate was bonded to the previous substrate with the surface on which the liquid crystal alignment film was formed facing inside, and the sealing material was cured to produce an empty cell. A negative liquid crystal MLC-3023 (trade name, manufactured by Merck & Co., Ltd.) was injected into this empty cell by a reduced pressure injection method to produce a liquid crystal cell.
Thereafter, with a DC voltage of 15 V applied to the obtained liquid crystal cell, 15 J/cm ² of ultraviolet light with a wavelength of 365 nm and passed through a bandpass filter was irradiated using an ultraviolet irradiation device using a high-pressure mercury lamp as a light source. As a result, a vertical alignment type liquid crystal display element was obtained. In addition, to measure the amount of ultraviolet irradiation, a UV-M03A manufactured by ORC Co., Ltd. was connected to a UV-35 light receiver.

<Evaluation of liquid crystal orientation>
The liquid crystal orientation of the liquid crystal display element was observed using a polarizing microscope (ECLIPSE E600WPOL) (manufactured by Nikon Corporation) to confirm whether the liquid crystal was vertically aligned. Specifically, those in which no defects due to liquid crystal flow or bright spots due to alignment defects were observed were evaluated as good.
[Examples 2 to 30 and Comparative Examples 1 to 4]
Liquid crystal alignment agents (S-2) to (S-30), (RS-1) to (RS-4) were prepared respectively. In addition, the filterability of each liquid crystal aligning agent was evaluated. Among these, liquid crystal alignment agents (S-2) to (S-3), (S-6) to (S-7), (S-9) to (S-19), (S-23) to ( S-30) was coated on a glass substrate with an ITO electrode in the same manner as in Example 1, and the printability and liquid crystal orientation were evaluated. For liquid crystal alignment agents (S-4), (S-5), (S-8), (S-20) to (S-22), use an alignment film printer (“Angstromer” manufactured by Nissha Printing Co., Ltd.). Printability and liquid crystal alignment were evaluated in the same manner as in Example 1, except that the liquid crystal aligning agent was applied using the following method. The results are shown in Table 2 below.

In Table 2, the numerical value of the polymer indicates the blending ratio (mass ratio) of each polymer with respect to the total amount of polymers used for preparing the liquid crystal aligning agent. The numerical value of the solvent composition indicates the blending ratio (mass ratio) of each compound to the total amount of the solvent used for preparing the liquid crystal aligning agent.
As can be seen from the above results, the liquid crystal alignment film obtained from the liquid crystal alignment agent of the example can obtain a liquid crystal alignment film that has excellent liquid crystal alignment properties compared to the liquid crystal alignment film obtained from the liquid crystal alignment agent of the comparative example. Can be done. Moreover, the liquid crystal aligning agent of an Example can obtain the liquid crystal aligning agent which is excellent in filterability and printability compared with the liquid crystal aligning agent of a comparative example.

The liquid crystal aligning agent of the present invention has excellent filterability and printability, and can provide a liquid crystal aligning film having excellent liquid crystal alignment properties. In addition, a liquid crystal display element having this liquid crystal alignment film can display high-quality images, and can be suitably used for large-screen, high-definition liquid crystal televisions, etc., and can be used especially for TN elements, STN elements, TFT liquid crystal elements, etc. It is useful for vertical alignment type liquid crystal display elements.

In addition, the entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2017-223900 filed on November 21, 2017 are cited here as a disclosure of the specification of the present invention. , is something to be taken in.

Claims (16)

At least one polymer selected from the group consisting of polyamic acid or polyamic acid ester having the structure of the following formula [1], and polyimide which is an imidized product thereof;
At least one solvent A selected from the group consisting of the following formulas (d-1) to (d-5) and the following formula (e), and from the group consisting of the following formulas (B-1) to (B-4) A solvent containing at least one selected solvent B;
A liquid crystal aligning agent characterized by containing,
The polyamic acid or polyamic acid ester comprises a tetracarboxylic acid compound and a diamine containing a diamine represented by the following formula [2] or a diamine compound containing a diamine represented by the following formula [2] and another diamine. The liquid crystal aligning agent obtained by the reaction.

In formula [1], X represents a single bond. The two Y's independently represent a side chain structure selected from the following formulas [S1] to [S3] or a structure derived from tocopherol.

However, X ¹ and X ² are independently a single bond, -(CH ₂ ) _a - (a is an integer from 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -COO-, -OCO-, or ((CH ₂ ) _a1 -A ₁ ) _m1 - (a1 represents an integer from 1 to 15, A ₁ is an oxygen atom, -COO or OCO, and m ₁ is 1 to 2). G ¹ and G ² are independently divalent cyclic groups selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms; Any of the above hydrogen atoms is an alkyl group having 1 to 3 carbon atoms, 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. may be replaced with . m and n are independently integers from 0 to 3, and their total is from 1 to 4. R ¹ is alkyl having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, or alkoxyalkyl having 2 to 20 carbon atoms, and any hydrogen atom in these groups may be substituted with a fluorine atom.
X ³ represents -CONH- , -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or OCO-, and R ² has a carbon number of 1 to It is an alkyl group having 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms, and any hydrogen atom in these groups may be substituted with a fluorine atom.
X ⁴ represents -CONH-, -NHCO-, -O-, -COO- or OCO-, and R ³ represents a structure having a steroid skeleton.

However, R _1a represents a monovalent hydrocarbon group having 1 to 8 carbon atoms, or a monovalent group having -O- between carbon-carbon bonds in the hydrocarbon group. R _2a and R _2b independently represent an alkyl group having 1 to 6 carbon atoms. R _3a represents a methyl group or an ethyl group, R _5a represents an alkyl group having 1 to 6 carbon atoms, and R _5b and R _5c independently represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms. , or a monovalent group having -O- between the carbon-carbon bonds of the hydrocarbon group. r _1a and r _1b independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, m is an integer of 2 to 6, and n is an integer of 1 or 2.

However, A _p1 and A _p2 independently represent an alkyl group having 1 to 6 carbon atoms, A _p5 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and A _q1 represents -O- or -COO-. , A _q2 represents a single bond or a carbonyl group, A _q3 represents -O-, A _k1 , A _k2 , and A _k6 independently represent an alkanediyl group having 2 to 4 carbon atoms, and n1 represents 1 ~3 is shown. A _p3 and A _p4 independently represent a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and A _x represents -C(OH)R _a -, -CHR _b - (R _a and R _b independently represent , hydrogen atom, methyl group, or ethyl group), -CO-, or -COO-* (* indicates the bonding position with A _k4 ), and A _k4 and A _k5 independently indicate the number of carbon atoms. Indicates 1 to 4 alkyl groups. m is an integer of 0 or 1, and n4 is an integer of 1 to 3. However, cases where n4 is 1, A _k6 is an alkanediyl group having 2 carbon atoms, and A _p5 is an alkyl group having 4 carbon atoms are excluded.

(However, X and Y have the same meanings as X and Y in the above formula [1].) The liquid crystal aligning agent according to claim 1, wherein the two Y's independently represent a side chain structure selected from the formulas [S1], [S3], or a structure derived from tocopherol. Solvent A is N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N-(n-hexyl)-2- Pyrrolidone, N-methoxypropyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, γ-butyrolactone, γ-valerolactone, γ-hexanolactone, 3-butoxy-N,N-dimethylpropanamide, The liquid crystal aligning agent according to claim 1 or 2, which is at least one solvent selected from the group consisting of 3-methoxy-N,N-dimethylpropanamide, ethylene carbonate, and propylene carbonate. The liquid crystal aligning agent according to any one of claims 1 to 3, wherein A _k1 in the formula (B-1) is an ethylene group, a 1,3-propanediyl group, or a 1,4-butanediyl group. The liquid crystal aligning agent according to any one of claims 1 to 4, wherein the content of solvent A in the solvent is 5 to 99% by mass, and the content of solvent B in the solvent is 1 to 95% by mass. . Solvent group B is diisobutyl ketone, diisobutyl carbinol, 4,6-dimethyl-2-heptanone, diacetone alcohol, n-butyl lactate, isoamyl lactate, butyl glycolate, ethyl-3-ethoxypropionate, propylene glycol monomethyl Ether, propylene glycol monobutyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl propyl ether, diethylene glycol propyl methyl ether, diethylene glycol butyl methyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate and propylene glycol The liquid crystal aligning agent according to any one of claims 1 to 5, which is at least one solvent selected from the group consisting of diacetate. The liquid crystal aligning agent according to any one of claims 1 to 6, wherein the solvent includes one combination selected from the group consisting of the following ms1 to ms12.
・ms1: N-methyl-2-pyrrolidone and propylene glycol monobutyl ether ・ms2: N-methyl-2-pyrrolidone and dipropylene glycol monomethyl ether ・ms3: N-methyl-2-pyrrolidone and dipropylene glycol dimethyl ether ・ms4: N -Methyl-2-pyrrolidone and propylene glycol monomethyl ether ・ms5: N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether ・ms6: N-ethyl-2-pyrrolidone and dipropylene glycol monomethyl ether ・ms7: N-ethyl-2 -Pyrrolidone and dipropylene glycol dimethyl ether・ms8: N-ethyl-2-pyrrolidone and propylene glycol monomethyl ether・ms9: N-methyl-2-pyrrolidone and isoamyl lactate・ms10: N-methyl-2-pyrrolidone and diacetone alcohol・ms11: γ-butyrolactone and ethyl-3-ethoxypropionate ms12: N-ethyl-2-pyrrolidone and diisobutyl ketone The liquid crystal aligning agent according to any one of claims 1 to 7, wherein the solvent contains three or more types consisting of one or more solvents A and one or more solvents B. The liquid crystal aligning agent according to claim 8, wherein the solvent includes one combination selected from the group consisting of MS1 to MS23 below.
・MS1: N-methyl-2-pyrrolidone, γ-butyrolactone, and propylene glycol monobutyl ether ・MS2: N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol monomethyl ether ・MS3: N-methyl-2-pyrrolidone and γ-Butyrolactone and dipropylene glycol dimethyl ether MS4: N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monomethyl ether MS5: N-ethyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether MS6: N - Ethyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol monomethyl ether ・MS7: N-ethyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether ・MS8: N-ethyl-2-pyrrolidone, γ-butyrolactone, and Propylene glycol monomethyl ether MS9: N-ethyl-2-pyrrolidone and N-methyl-2-pyrrolidone and propylene glycol monobutyl ether MS10: N-ethyl-2-pyrrolidone and N-methyl-2-pyrrolidone and dipropylene glycol monomethyl Ether/MS11: N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, and dipropylene glycol dimethyl ether/MS12: N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, γ-butyrolactone, and propylene glycol monomethyl Ether・MS13: N-methyl-2-pyrrolidone, diacetone alcohol, and diethylene glycol diethyl ether・MS14: N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol monomethyl ether・MS15: N-methyl-2-pyrrolidone and N-ethyl-2-pyrrolidone and diisobutyl carbinol ・MS16: N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether and diisobutyl ketone ・MS17: N-ethyl-2-pyrrolidone and ethylene glycol monobutyl ether acetate and dipropylene glycol Monomethyl ether MS18: N-ethyl-2-pyrrolidone and N-methyl-2-pyrrolidone and diacetone alcohol MS19: γ-butyrolactone and 1,3-dimethyl-2-imidazolidinone and ethyl-3-ethoxypropio MS20: N-methyl-2-pyrrolidone and 3-methoxy-N,N-dimethylpropanamide and diacetone alcohol MS21: N-methyl-2-pyrrolidone and propylene carbonate and diacetone alcohol MS22: N-methyl -2-pyrrolidone, butyl glycolate, and dipropylene glycol dimethyl ether ・MS23: N-ethyl-2-pyrrolidone, diacetone alcohol, and propylene glycol monobutyl ether ・MS24: N-ethyl-2-pyrrolidone, diacetone alcohol, and ethyl-3 -Ethoxypropionate MS25: γ-valerolactone and γ-butyrolactone and ethyl-3-ethoxypropionate MS26: N-methyl-2-pyrrolidone and diethylene glycol diethyl ether and dipropylene glycol monomethyl ether MS27: N- Methyl-2-pyrrolidone, propylene glycol monobutyl ether, diethylene glycol butyl methyl ether, MS28: N-ethyl-2-pyrrolidone, diethylene glycol ethyl methyl ether, diisobutyl ketone, MS29: N-methyl-2-pyrrolidone, diacetone alcohol, and propylene glycol. diacetate The liquid crystal aligning agent according to claim 9 , wherein the other diamine is a diamine having a function of polymerizing or generating radicals upon irradiation with light. The liquid crystal aligning agent according to any one of claims 1 to 10, wherein the tetracarboxylic acid compound contains a tetracarboxylic dianhydride having a structure represented by the following formula [4] or a derivative thereof.

However, Z represents a structure selected from [4a] to [4k] below.

However, *1 is a bonding position that is bonded to one acid anhydride group, and *2 is a bonding position that is bonded to the other acid anhydride group. In formula [4a], Z ¹ to Z ⁴ independently represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom, or a benzene ring. In formula [4g], Z ⁵ and Z ⁶ are independently a hydrogen atom or a methyl group. Claims 1 to 11, wherein the tetracarboxylic acid compound contains 5 mol% or more of a tetracarboxylic dianhydride or a derivative thereof having a structure represented by the following formula [4] in 100 mol% of the tetracarboxylic acid compound. The liquid crystal aligning agent according to any one of the items. A method for producing a liquid crystal aligning film, which comprises applying the liquid crystal aligning agent according to any one of claims 1 to 12 onto a substrate surface by flexographic printing or inkjet method, and firing. A liquid crystal aligning film obtained from the liquid crystal aligning agent according to any one of claims 1 to 12. A liquid crystal layer is provided between a pair of substrates provided with electrodes, a liquid crystal composition containing a polymerizable compound that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates, and the electrode The liquid crystal alignment film according to claim 14, which is used in a liquid crystal display element manufactured through a step of polymerizing the polymerizable compound while applying a voltage therebetween. A liquid crystal display element comprising the liquid crystal alignment film according to claim 14.