JP7552582B2 - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element using the same - Google Patents

Description

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element using the same.

Various driving methods have been developed for liquid crystal display elements, which differ in electrode structure, physical properties of the liquid crystal molecules used, manufacturing process, etc., and known liquid crystal display elements include, for example, TN (twisted nematic) type, STN (super-twisted nematic) type, VA (vertical alignment) type, MVA (multi-domain vertical alignment) type, IPS (in-plane switching) type, FFS (fringe field switching) type, and PSA (polymer-sustained alignment) type.
These liquid crystal display elements are provided with a liquid crystal alignment film to align the liquid crystal molecules. The material for the liquid crystal alignment film is generally a coating made of a polymer such as polyamic acid, polyimide, or polysiloxane, because these have various good properties such as heat resistance, mechanical strength, and affinity with liquid crystal.

In recent years, there has been an increasing demand for high image quality in liquid crystal display elements. For example, there is a demand for liquid crystal display elements that have low accumulated charge while maintaining a high voltage retention rate, and Patent Document 1 discloses a liquid crystal alignment agent that contains a specific compound.

JP2008-052260

Furthermore, with the widespread use of so-called touch panel type liquid crystal display elements, users often apply strong pressure to these display elements with their fingers. When this happens, the spacers inside the liquid crystal display element move within the liquid crystal display element and rub against the liquid crystal alignment film. The liquid crystal alignment film, stressed by the spacers, is unable to regulate the alignment of the liquid crystals, and this causes a problem in that, even when the liquid crystal display element is displaying black, for example, light escapes from the periphery of the spacers, resulting in the display of bright spots.

The configurations of liquid crystal alignment agents proposed in the past have not necessarily been able to achieve all of the above-mentioned problems. The present invention has been made based on the above circumstances, and its purpose is to provide a liquid crystal display element that maintains a high voltage retention rate, has little accumulated charge, and can minimize bright spots even when physical friction such as rubbing by a spacer occurs. It is also an object of the present invention to provide a liquid crystal alignment film and a liquid crystal alignment agent suitable for such liquid crystal display elements.

The inventors conducted extensive research and discovered that the above problems could be solved by using a liquid crystal alignment agent containing specific components, which led to the completion of the present invention. Specifically, the gist of the present invention is as follows:

式（１）中、Ｘ_１は４価の有機基であり、Ｙ_１は２価の有機基である。Ｒ_１は水素原子、又は炭素数１～５のアルキル基であり、Ｚ_１１、Ｚ_１２はそれぞれ独立して水素原子、置換基を有してもよい炭素数１～１０のアルキル基、置換基を有してもよい炭素数２～１０のアルケニル基、置換基を有してもよい炭素数２～１０のアルキニル基、ｔｅｒｔ－ブトキシカルボニル基、又は９－フルオレニルメトキシカルボニル基である。

＊は結合手を表し、Ｒ_１は、炭素数１～４のアルカンジイル基を表す。ｍ_１は、１～２の整数を表す。 A liquid crystal aligning agent comprising the following components (A) and (B):
Component (A): A polymer (A) having at least one repeating unit selected from the group consisting of a repeating unit represented by the following formula (1) and a repeating unit represented by the following formula (2):
Component (B): A compound (B) having a molecular weight of 2000 or less, which has a partial structure represented by the following formula (b) in the molecule and is equipped with a basic site containing a nitrogen atom.

In formula (1), _X1 is a tetravalent organic group, _Y1 is a divalent organic group, _R1 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and _Z11 and _Z12 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent, an alkenyl group having 2 to 10 carbon atoms which may have a substituent, an alkynyl group having 2 to 10 carbon atoms which may have a substituent, a tert-butoxycarbonyl group, or a 9-fluorenylmethoxycarbonyl group.

* represents a bond, _R1 represents an alkanediyl group having 1 to 4 carbon atoms, and _m1 represents an integer of 1 or 2.

The liquid crystal alignment agent of the present invention makes it possible to obtain a liquid crystal display element that maintains a high voltage retention rate while having little accumulated charge and that can minimize bright spots even when physical friction occurs, such as rubbing with a spacer, and a liquid crystal alignment film that provides this.

Hereinafter, each component contained in the liquid crystal aligning agent of the present disclosure and other components that are optionally blended as necessary will be described.
<Polymer (A)>
The liquid crystal aligning agent of the present invention contains a polymer (A) having at least one repeating unit selected from the group consisting of the repeating unit represented by the above formula (1) and the repeating unit represented by the above formula (2).
Specific examples of the alkyl group having 1 to 5 carbon atoms for R ₁ in the above formula (2) include a methyl group, an ethyl group, a propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, an n-pentyl group, etc. From the viewpoint of ease of imidization by heating, R ₁ is preferably a hydrogen atom or a methyl group.

Specific examples of the alkyl group having 1 to 10 carbon atoms for Z ₁₁ and Z ₁₂ in the above formula (2) include, in addition to the specific examples of the alkyl group having 1 to 5 carbon atoms exemplified for R ₁ , a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, etc. Specific examples of the alkenyl group having 2 to 10 carbon atoms for Z ₁₁ and Z ₁₂ include a vinyl group, a propenyl group, a butynyl group, etc., which may be linear or branched. Specific examples of the alkynyl group having 2 to 10 carbon atoms for Z ₁₁ and Z ₁₂ include an ethynyl group, a 1-propynyl group, a 2-propynyl group, etc.

The above Z ₁₁ and Z ₁₂ may each have a substituent, and examples of the substituent include a halogen atom (such as a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc.), a hydroxyl group, a cyano group, and an alkoxy group.

From the viewpoint of reducing afterimages, it is preferable that Z ₁₁ and Z ₁₂ each independently represent a hydrogen atom or a methyl group.

In the above formulas (1) and (2), X ₁ and Y ₁ are as defined above. X ₁ in formula (1) is a tetravalent organic group derived from at least one selected from the group consisting of tetracarboxylic dianhydrides, tetracarboxylic diesters, and tetracarboxylic diester dihalides (hereinafter, these are also collectively referred to as "tetracarboxylic acid derivatives"). Specific examples include tetravalent organic groups derived from aromatic tetracarboxylic dianhydrides, aliphatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, or tetracarboxylic diesters or tetracarboxylic diester dihalides thereof. Y ₁ in formula (1) is a divalent organic group derived from a diamine.

Here, the aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to an aromatic ring. The aliphatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups bonded to a chain hydrocarbon structure. However, it is not necessary to be composed of only a chain hydrocarbon structure, and it may have an alicyclic structure or an aromatic ring structure as a part of it. The alicyclic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded to an alicyclic structure. However, none of these four carboxyl groups are bonded to an aromatic ring. Also, it is not necessary to be composed of only an alicyclic structure, and it may have a chain hydrocarbon structure or an aromatic ring structure as a part of it.

ｘ及びｙは、単結合、エーテル、カルボニル、エステル、炭素数１～５のアルカンジイル基、１，４－フェニレン、スルホニル又はアミド基である。Ｚ^１～Ｚ^６は、それぞれ独立して、水素原子、メチル基、エチル基、プロピル基、塩素原子又はベンゼン環を表す。ｊ及びｋは、０又は１である。ｍは１～５の整数である。＊は結合手を表す。 From the viewpoint of obtaining a high voltage holding ratio and suppressing bright spots caused by physical friction, _X1 is preferably a tetravalent organic group selected from the group consisting of the following formulae (4a) to (4n), (5a) and (6a):

Each of x and y is a single bond, ether, carbonyl, ester, an alkanediyl group having 1 to 5 carbon atoms, 1,4-phenylene, sulfonyl, or amide. Each of Z ¹ to Z ⁶ independently represents a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom, or a benzene ring. Each of j and k is 0 or 1. m is an integer of 1 to 5. * represents a bond.

From the viewpoint of obtaining a high voltage holding ratio and suppressing bright spots caused by physical friction, preferred specific examples of the above formula (4a) include structures represented by the following formulas (4a-1) to (4a-4).

Examples of the alkanediyl groups having 1 to 5 carbon atoms in the above formulas (5a) and (6a) include methylene, ethylene, 1,3-propanediyl, 1,4-butanediyl, 1,5-pentanediyl, etc.

From the viewpoint of obtaining a high voltage holding ratio and suppressing bright spots caused by physical friction, X ₁ in the above formula (1) may be a tetravalent organic group selected from the above formulas (4a) to (4h), (4j), (4l), and (4m) to (4n).

From the viewpoint of obtaining a high voltage holding ratio and suppressing bright spots caused by physical friction, the content _{of one or} more kinds of repeating units selected from the group consisting of repeating units represented by formula (1) and repeating units represented by formula (2), in which X _{1 is a tetravalent organic group selected from the group consisting of formulas (4a) to (4n), (5a), and (6a), and Y 1} is a divalent organic group (hereinafter also referred to as repeating units (t)), may be 5 mol % or more, 10 mol % or more, or 20 mol % or more in total, based on all repeating units of polymer (A).

Examples of _Y1 in formula (1) include divalent organic groups derived from diamines, such as divalent organic groups derived from aliphatic diamines, alicyclic diamines, or aromatic diamines. Specific examples of aliphatic diamines include metaxylylenediamine, ethylenediamine, 1,3-propanediamine, tetramethylenediamine, and hexamethylenediamine; alicyclic diamines include 1,4-cyclohexanediamine and 4,4'-methylenebis(cyclohexylamine);

Ｒ^３は、－ＮＲＣＯ－、－ＣＯＯ－、－ＮＲＣＯＮＲ－、－（ＣＨ_２）_ｎ－（ただし、ｎは２～２０の整数）で表される構造であり、任意の－ＣＨ_２－は－Ｏ－、－ＣＯＯ－、－ＮＤ－、－ＮＲＣＯ－、－ＮＲＣＯＮＲ－、－ＮＲＣＯＯ－、－ＯＣＯＯ－に置き換えられてもよい。Ｄは熱脱離性基を表し、Ｒは水素原子又は１価の有機基を表す。Ｒ^４は単結合又はベンゼン環であり、ベンゼン環上の任意の水素原子は１価の有機基で置き換えられてもよい。

Ｘ_１は、－ＣＯ－、－Ｏ－、－ＣＯＯ－、－Ｌ_１－Ｒ－Ｌ_２－（Ｌ_１、Ｌ_２は、それぞれ独立に、単結合、酸素原子又は－ＣＯＯ－であり、Ｒは－（ＣＨ_２）_ｎ－（ｎは１～１２の整数）である。）、又は－ＮＲＣＯ－（Ｒは水素原子又はメチル基を表す。）を表し、Ｘ_２は単結合、－ＮＲＣＯ－（Ｒは水素原子又はメチル基を表す。）又は－ＣＯＯ－を表す。ｎは１～２の整数を表す。ベンゼン環上の任意の水素原子は１価の有機基で置き換えられてもよい。

式中、２個あるＸは、それぞれ独立に、－Ｏ－、－ＣＯＯ－、－ＮＨＣＯ－、－Ｃ（＝Ｏ）－又は－（ＣＨ_２）_ｎ－（ｎは１～１２の整数）を表し、Ｌ_１、Ｌ_２は、それぞれ独立に、単結合、－Ｏ－又は－ＣＯＯ－であり、Ｒは－ＣＨ_２－であるか、－（ＣＨ_２）_ｎ－（ｎは２～１２の整数）、又は上記－（ＣＨ_２）_ｎ－の任意のＣＨ_２が酸素原子で置換された基を表す。ベンゼン環上の任意の水素原子は１価の有機基で置き換えられてもよい。 Examples of aromatic diamines include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenyl ether, 4,4'-diaminoazobenzene, 1-(4-aminophenyl)-1,3,3-trimethyl-1H-indan-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine, nitrogen-containing heterocycles, diphenylamine structures, and triphenylamine structures. Examples of aromatic diamines include diamines having at least one selected from the group consisting of diphenylamine structures and triphenylamine structures (hereinafter also referred to as "nitrogen-containing diamines"). Examples of aromatic diamines include 3,5-diaminobenzoic acid, 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]ether, 4,4'-bis(4- (aminophenoxy)biphenyl, 1,3-bis(3-aminopropyl)-tetramethyldisiloxane, diamines represented by the following formula (H), diamines represented by the following formulas (H2) to (H3), diamines represented by the following formulas (V-1) to (V-3), diamines having a radical initiating function represented by the following formulas (R1) to (R5), 2-(2,4-diaminophenoxy)ethyl methacrylate, 2,4-diamino-N,N-diallylaniline, etc. Examples of the diamine having a photopolymerizable group at an end include the diamine having a photoalignment structure described in paragraph [0053] of International Publication WO2014/080865, the diamine having a carbon-carbon unsaturated bond described in paragraph [0057], the diamine having an azobenzene skeleton described in paragraph [0058], and the photoreactive diamine described in paragraphs [0069] to [0072] of International Publication WO2012/086715.

^R3 is a structure represented by -NRCO-, -COO-, -NRCONR-, or -(CH ₂ ) _n - (wherein n is an integer of 2 to 20), and any -CH ₂ - may be replaced by -O-, -COO-, -ND-, -NRCO-, -NRCONR-, -NRCOO-, or -OCOO-. D represents a thermally detachable group, and R represents a hydrogen atom or a monovalent organic group. ^R4 is a single bond or a benzene ring, and any hydrogen atom on the benzene ring may be replaced by a monovalent organic group.

X ₁ represents -CO-, -O-, -COO-, -L ₁ -R-L ₂ - (L ₁ and L ₂ are each independently a single bond, an oxygen atom or -COO-, and R is -(CH ₂ ) _n - (n is an integer of 1 to 12)), or -NRCO- (R represents a hydrogen atom or a methyl group), and X ₂ represents a single bond, -NRCO- (R represents a hydrogen atom or a methyl group) or -COO-. n represents an integer of 1 or 2. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group.

In the formula, two Xs each independently represent -O-, -COO-, -NHCO-, -C(=O)- or -( _CH2 ) _n- (n is an integer of 1 to 12), _L1 and _L2 each independently represent a single bond, -O- or -COO-, and R represents _-CH2- , -( _CH2 ) _n- (n is an integer of 2 to 12) or a group in which any _CH2 in the -( _CH2 ) _n- is replaced with an oxygen atom. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group.

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－又は－ＣＯＯ－（ＣＨ_２）_ｍ－ＯＣＯ－を表す。
Ｘ^１及びＸ^２はそれぞれ独立して、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－を表す。このうち、複数のａ１はそれぞれ独立して１～１５の整数であり、複数のＡ_１はそれぞれ独立して酸素原子又は－ＣＯＯ－を表し、ｍ_１は１～２である。Ｘ^３は単結合、－ＣＯＮＨ－、－ＮＨＣＯ－、－ＣＯＮ（ＣＨ_３）－、－ＮＨ－、－Ｏ－、－ＣＨ_２Ｏ－、－ＣＯＯ－又は－ＯＣＯ－を表す。Ｘ^４は－ＣＯＮＨ－、－ＮＨＣＯ－、－Ｏ－、－ＣＯＯ－又は－ＯＣＯ－を表す。
Ｇ_１及びＧ_２は、それぞれ独立して、フェニレン、ビフェニレン、ナフタレンなどの炭素数６～１２の２価の芳香族基又はシクロプロピレン、シクロヘキシレンなどの炭素数３～８の２価の脂環式基から選ばれる２価の環状基を表す。該環状基上の任意の水素原子は、炭素数１～３のアルキル基、炭素数１～３のアルコキシ基、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基又はフッ素原子で置換されていてもよい。ｋは０または１を表し、ｍ及びｎは、それぞれ独立して、０～３の整数であって、ｍ及びｎの合計は１～４である。
Ｒ^１は、炭素数１～２０のアルキル基、炭素数１～２０のアルコキシ基又は炭素数２～２０のアルコキシアルキル基を表す。Ｒ^１を形成する任意の水素はフッ素で置換されていてもよい。
Ｒ^２は炭素数１～２０のアルキル基又は炭素数２～２０のアルコキシアルキル基を表し、Ｒ^２を形成する任意の水素はフッ素で置換されていてもよい。Ｒ^３はステロイド骨格を有する構造を表す。

X represents a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 ) _m- , -SO2-, -O-( _CH2 ) _m -O-, -O-C( _CH3 ) _2- , _-CO- ( _CH2 ) _m- , -NH-( _CH2 ) _m- , _-SO2- ( _CH2 )m-, -CONH-( _CH2 ) _m- , -CONH-( _CH2 ) _m- NHCO- or -COO-( _CH2 ) _{m -} OCO-.
X ¹ and X ² each independently represent a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -COO-, -OCO-, or -((CH ₂ ) _a1 -A ₁ ) _m1 -. Among these, a1's each independently represent an integer of 1 to 15, A ₁ 's each independently represent an oxygen atom or -COO-, and m ₁ is 1 to 2. X ³ represents a single bond, -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or -OCO-. X ⁴ represents -CONH-, -NHCO-, -O-, -COO-, or -OCO-.
_G1 and _G2 each independently represent a divalent cyclic group selected from divalent aromatic groups having 6 to 12 carbon atoms, such as phenylene, biphenylene, and naphthalene, and divalent alicyclic groups having 3 to 8 carbon atoms, such as cyclopropylene and cyclohexylene. Any hydrogen atom on the cyclic group may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms, or a fluorine atom. k represents 0 or 1, m and n each independently represent an integer of 0 to 3, and the sum of m and n is 1 to 4.
^R1 represents 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. Any hydrogen forming ^R1 may be substituted with fluorine.
^R2 represents an alkyl group having 1 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms, and any hydrogen atom forming ^R2 may be substituted with a fluorine atom. ^R3 represents a structure having a steroid skeleton.

ｎは２～１０の整数を表す。

n represents an integer of 2 to 10.

Specific examples of the nitrogen-containing heterocycle include pyrrole, imidazole, pyridine, pyrimidine, pyridazine, pyrazine, carbazole, benzimidazole, piperidine, piperazine, pyrrolidine, and hexamethyleneimine, and examples of the diphenylamine structure include diphenylamine, N-methyldiphenylamine, and N-tert-butoxycarbonyldiphenylamine. Specific examples of the nitrogen-containing diamine include 2,6-diaminopyridine, 3,4-diaminopyridine, 3,5-diamino-N-(pyridin-3-ylmethyl)benzamide, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, bis(4-aminophenyl)amine, N,N-bis(4-aminophenyl)methylamine, N,N'-bis(4-aminophenyl)methylamine, and N,N'-bis(4-aminophenyl)methylamine. )-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, 1,4-bis(4-aminophenyl)-piperazine, 4-(4-aminophenoxycarbonyl)-1-(4-aminophenyl)piperidine, 4,4'-[4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)]dianiline, and diamines represented by the following formulas (z-1) to (z-19).

Ｂｏｃはｔｅｒｔ－ブトキシカルボニル基を表す。

Boc represents a tert-butoxycarbonyl group.

In the above formulas (H), (H2), and (H3), the hydrogen atom on the benzene ring may be replaced by a monovalent organic group such as an alkyl group having 1 to 5 carbon atoms, such as a methyl group or an ethyl group; an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group; a halogen atom, such as a fluorine atom; a halogenated alkyl group having 1 to 5 carbon atoms, such as a trifluoromethyl group; -NR ₁ R ₂ (R ₁ and R ₂ each represent a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), a cyano group, or a hydroxyl group.

（Ｒは水素原子、メチル基又はｔｅｒｔ－ブトキシカルボニル基を表す。Ｂｏｃは、ｔｅｒｔ－ブトキシカルボニル基を表す。） From the viewpoint of enhancing the liquid crystal alignment property, among the diamines represented by the above formula (H), diamines represented by the following formulas (H-1) to (H-17) may be used.

(R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group. Boc represents a tert-butoxycarbonyl group.)

Ｒは水素原子、メチル基、又はｔｅｒｔ－ブトキシカルボニル基を表す。＊は結合手を表す。Ｂｏｃはｔｅｒｔ－ブトキシカルボニル基を表す。 From the viewpoint of enhancing the liquid crystal alignment property, among the diamines represented by the above formula (H2), diamines represented by the following formulas (H2-1) to (H2-17) may be used.

R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group. * represents a bond. Boc represents a tert-butoxycarbonyl group.

From the viewpoint of enhancing the liquid crystal alignment property, among the diamines represented by the above formula (H3), diamines represented by the following formulas (H3-1) to (H3-4) may be used.

式中、Ｘ^ｖ１～Ｘ^ｖ４、Ｘ^ｐ１～Ｘ^ｐ８は、はそれぞれ独立して、－（ＣＨ_２）_ａ－（ａは１～１５の整数である）、－ＣＯＮＨ－、－ＮＨＣＯ－、－ＣＯＮ（ＣＨ_３）－、－ＮＨ－、－Ｏ－、－ＣＨ_２Ｏ－、－ＣＨ_２ＯＣＯ－、－ＣＯＯ－、又は－ＯＣＯ－を示し、Ｘ^ｖ５は－Ｏ－、－ＣＨ_２Ｏ－、－ＣＨ_２ＯＣＯ－、－ＣＯＯ－、又は－ＯＣＯ－を示し、Ｘ^Ｖ６～Ｘ^Ｖ７、Ｘ^ｓ１～Ｘ^ｓ４はそれぞれ独立して、－Ｏ－、－ＣＯＯ－又は－ＯＣＯ－を示す。Ｘ_ａ～Ｘ_ｆは、単結合、－Ｏ－、－ＮＨ－、又は－Ｏ－（ＣＨ_２）_ｍ－Ｏ－を示し、Ｒ^ｖ１～Ｒ^ｖ４、Ｒ^１ａ～Ｒ^１ｈはそれぞれ独立して、炭素数１～２０のアルキル基、炭素数１～２０のアルコキシ基または炭素数２～２０のアルコキシアルキル基を示す。ｍは１～８の整数を表す。 From the viewpoint of enhancing the liquid crystal alignment property, among the diamines (V-1) to (V-3), diamines represented by the following formulas (V2-1) to (V2-13) may be used.

In the formula, X ^v1 to X ^v4 and X ^p1 to X ^p8 each independently represent -(CH ₂ ) _a - (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-; X ^v5 represents -O-, -CH ₂ O-, -CH ₂ OCO-, -COO-, or -OCO-; and X ^v6 to X ^v7 and X ^s1 to X ^s4 each independently represent -O-, -COO-, or -OCO-. X _a to X _f each represent a single bond, —O—, —NH—, or —O—(CH ₂ ) _m —O—, and R ^v1 to R ^v4 and R ^1a to R ^1h each 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 represents an integer of 1 to 8.

When applied to a liquid crystal aligning agent for a TN-type, STN-type or vertical alignment type liquid crystal display element, from the viewpoint of enhancing liquid crystal alignment, the polymer (A) may contain _one or more repeating units (hereinafter also referred to as repeating units (a)) selected from the group consisting of repeating units represented by the above formula (1) and repeating units represented by the above formula (2), in which X ₁ is a tetravalent organic group and Y 1 is a divalent organic group derived from a diamine represented by the above formulas (V1) to (V3). From the viewpoint of enhancing liquid crystal alignment, the content of the repeating units (a) may be 1 mol % or more, 3 mol % or more, or 5 mol % or more in total, based on the total repeating units of the polymer (A).

When applied to a liquid crystal alignment agent for a PSA type liquid crystal display element, from the viewpoint of enhancing liquid crystal alignment, the polymer (A) may contain one or more repeating units (hereinafter also referred to as repeating units (b)) selected from the group consisting of repeating units represented by the above formula ( _{1 )} and repeating units represented by the above formula (2), in which X 1 is a tetravalent organic group and Y 1 is a divalent organic group derived from a diamine selected from the group consisting of diamines having the above radical initiation function and diamines having the above photopolymerizable group at their ends. From the viewpoint of enhancing liquid crystal alignment, the content of the repeating unit (b) may be 1 mol% or more, 3 mol% or more, or 5 mol% or more in total, based on the total repeating units of the polymer (A). In this case, the polymer (A) may use one or more repeating units (a) in combination. The upper limit of the content of the repeating unit (a) and the repeating unit (b) may be 99 mol% or less, 97 mol% or less, or 95 mol% or less, based on the total repeating units of the polymer (A). In this case, repeating units other than the repeating units (a) and (b) may be contained depending on the purpose.

When the polymer (A) is applied to a liquid crystal aligning agent for an IPS-type or FFS-type liquid crystal display device, from the viewpoint of enhancing the liquid crystal alignment property, _X1 is a tetravalent organic group, and Y The repeating unit represented by the formula (1) and the repeating unit represented by the formula (2) above may contain one or more repeating units (hereinafter also referred to as repeating unit (c)). ₁ is a divalent organic group derived from a diamine selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylether, 4,4'-diaminoazobenzene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]ether, 4,4'-bis(4-aminophenoxy)biphenyl, diamines represented by the formula (H) above, and diamines represented by the formulas (H2) to (H3). From the viewpoint of improving the liquid crystal alignment property, the content of the repeating unit (c) may be 5 mol % or more, or 10 mol % or more in total, based on all the repeating units of the polymer (A).

When imparting liquid crystal alignment ability to a coating film formed by a liquid crystal alignment agent by a photoalignment method, the polymer (A) may contain one or more repeating units (hereinafter also referred to as repeating units (d)) selected from the group consisting of repeating units represented by the above formula ( _{1 )} and repeating units represented by the above formula (2) in which X 1 is a tetravalent organic group and Y 1 is a divalent organic group derived from a diamine selected from the group consisting of a diamine having the above photoalignment structure, a diamine having a carbon-carbon unsaturated bond, a diamine having an azobenzene skeleton, and a diamine having the above photoreactivity. From the viewpoint of imparting liquid crystal alignment ability, the content of the repeating unit (d) may be 20 mol% or more, or 30 mol% or more in total, based on the total repeating units of the polymer (A). In addition, from the viewpoint of imparting liquid crystal alignment ability by a photoalignment method and maintaining a high voltage retention rate, the _polymer (A) may contain one or more repeating units (hereinafter also referred to as repeating units (e)) selected from the group consisting of repeating units represented by the above formula (1) and repeating units represented by the above formula (2), in which _X1 is any of the above formulas (4a) to (4c), (4f) to (4g), and Y1 is a divalent organic group. The content of the repeating units (e) may be 5 mol% or more, or 10 mol% or more in total, based on the total repeating units of the polymer (A).

From the viewpoint of low accumulated charge, the polymer (A) may contain one or more repeating units (hereinafter also referred to as repeating _units (n)) selected from the group consisting of repeating units represented by the above formula (1) and repeating units represented by the above formula (2), in which _X1 is a tetravalent organic group and Y1 is a divalent organic group derived from a nitrogen-containing diamine. The content of the repeating units (n) may be 5 mol% or more, or 10 mol% or more in total, based on the total repeating units of the polymer (A).

The liquid crystal alignment agent of the present invention may contain one type of polymer (A) or may contain two or more types of polymer (A). Specific examples of the case where the polymer (A) is of two or more types include an embodiment in which at least one type of polymer having the repeating unit (t) and any one of the repeating units (a) to (e) is contained, from the viewpoint of low accumulated charge and suppression of bright spots caused by physical friction. In addition, an embodiment in which at least one type of polymer having the repeating unit (n) is contained, from the viewpoint of low accumulated charge. In addition, when the polymer (A) is composed of two types, the blending ratio of the first polymer and the second polymer ((first polymer)/(second polymer)) may be 5/95 to 95/5, 10/90 to 90/10, or 20/80 to 80/20 by mass, from the viewpoint of improving the liquid crystal alignment, low accumulated charge, and suppression of bright spots caused by physical friction.

<Compound (B)>
The liquid crystal alignment agent of the present invention contains the compound (B). The compound (B) has a basic site containing a nitrogen atom in the molecule, which increases the imidization rate of the polymer (A) during baking, and the resulting liquid crystal alignment film has a high voltage retention rate. In addition, since the compound (B) has a methylol group in the molecule, a crosslinking reaction occurs between the polymer (A) and the compound (B) or between the compounds (B), so that the film strength of the resulting liquid crystal alignment film can be increased. Therefore, the liquid crystal display element having the liquid crystal alignment film of the present invention can minimize bright spots even when physical friction such as rubbing by a spacer occurs. In addition, the compound (B) has the effect of increasing the crosslink density of the liquid crystal alignment film, and therefore has excellent ability to capture impurity components derived from the substrate, and therefore the resulting liquid crystal alignment film has a high voltage retention rate. In addition, since the compound (B) has a phenylene site in the molecule, charge transfer in the liquid crystal alignment film is promoted, and a liquid crystal alignment film with less accumulated charge can be obtained.

The basic site means a site in which the pKa of the conjugate acid is −3 or more. This pKa is preferably within the range of −3 to 15, and more preferably within the range of 0 to 15. This pKa means a calculated value obtained by ACD/ChemSketch (ACD/Labs 8.00 Release Product Version: 8.08).
The basic site includes, for example, a structure selected from the group consisting of a secondary amine, a group in which one or two hydrogen atoms have been removed from a tertiary amine, and a nitrogen-containing heterocyclic group. Examples of the secondary amine or tertiary amine include an aliphatic amine and an aromatic amine.
Examples of aromatic amines include structures in which at least one aromatic ring, such as a benzene ring, is bonded to a nitrogen atom. The hydrogen atom on the benzene ring may be unsubstituted or substituted with a monovalent organic group, and examples of the monovalent organic group include halogen atoms (fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc.), alkyl groups having 1 to 5 carbon atoms such as a methyl group, alkoxy groups having 1 to 5 carbon atoms such as a methoxy group, a nitro group, a hydroxyl group, an amino group, a mercapto group, a nitroso group, an alkylsilyl group, an alkoxysilyl group, a silanol group, a sulfino group, a phosphino group, a carboxyl group, a cyano group, a sulfo group, an acyl group, and a "-R ₁ -OH" group (R ₁ is an alkanediyl group having 1 to 4 carbon atoms).

The nitrogen-containing heterocycle may be a monocyclic or polycyclic one. Specific examples of the nitrogen-containing heterocycle include pyrrole, imidazole, pyrazole, triazole, pyridine, pyrimidine, pyridazine, pyrazine, indole, benzimidazole, purine, quinoline, isoquinoline, naphthyridine, quinoxaline, phthalazine, triazine, thiazole, isothiazole, benzothiazole, 5,6,7,8-tetrahydroquinoline, piperidine, piperazine, pyrrolidine, hexamethyleneimine, decahydroquinoline, imidazoline, and carbazole.
In the partial structure represented by the above formula (b), examples of the alkanediyl group having 1 to 4 carbon atoms for R ₁ include a methylene group, an ethylene group, a propanediyl group, and a butanediyl group. Among these, a methylene group is preferred from the viewpoint of a high crosslinking effect. _{m 1} is preferably 2 from the viewpoint of a high crosslinking effect.
From the viewpoint of ease of synthesis, the compound (B) is preferably at least one compound selected from the group consisting of the following formulae (B1), (B2-1) to (B2-2), and (B3-1) to (B3-3).

R ₁ represents an alkanediyl group having 1 to 4 carbon atoms. L ₁ represents a divalent organic group selected from the following formulae (L1-1) to (L1-3). S _21a and S _21b each independently represent a (m _2a +2) or (m _2b +2)-valent organic group represented by the following formula (2S-1) or (2S-2). S ₂₂ and S ₃₂ each independently represent a single bond, -O-, -CO-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -(CH ₂ ) _n - (n represents an integer of 2 to 20), or a divalent organic group in which non-adjacent CH ₂ in the -(CH ₂ ) _n - is replaced with -O-, -CO-, -CH(CH ₃ )-, or -C(CH ₃ ) ₂ -.
S _31a represents a single bond, -O-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -(CH ₂ ) _n - (n is an integer of 2 to 18), -CO-, -C≡C-, -CH═CH-, a phenylene group, a divalent organic group selected from the above formulas (M-1) to (M-10), or a divalent organic group in which any CH ₂ in the above -(CH ₂ ) _n - is replaced by -O-, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -CO-, a phenylene group, or a divalent organic group selected from the above formulas (M-1) to (M-11).
S _31b represents a divalent organic group defined for S _31a , as well as a divalent organic group represented by the above formula (M-11), -C(R ₃₂ ) _2-m3b (Q _3b ) _m3b - (m _3b represents an integer of 1 to 2, and R ₃₂ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).
R ₂ , R ₃₁ and R ₃₃ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

Ｍは、下記式（Ｍ－１）～（Ｍ－１１）から選ばれる２価の有機基を表す。Ｒ_１、Ｒ_２はそれぞれ独立して、水素原子又はメチル基を表す。Ｔ_１、Ｔ_２はそれぞれ独立に、単結合、－Ｏ－、－ＮＲ－（Ｒは水素原子又はメチル基を表す。）、－ＣＯＮＲ－（Ｒは水素原子又はメチル基を表す。）、－ＮＲＣＯＮＲ－（Ｒは水素原子又はメチル基を表す。）、フェニレン基、－ＣＨ_２－、－ＣＨ（ＣＨ_３）－、－Ｃ（ＣＨ_３）_２－、－（ＣＨ_２）_ｎ－（ｎは２～２０の整数）、又は上記－（ＣＨ_２）_ｎ－の任意のＣＨ_２が、－ＣＨ（ＣＨ_３）－、－Ｃ（ＣＨ_３）_２－）、－Ｏ－、－ＮＲ－（Ｒは水素原子又はメチル基を表す。）、－ＣＯＮＲ－（Ｒは水素原子又はメチル基を表す。）、－ＮＲＣＯＮＲ－（Ｒは水素原子又はメチル基を表す。）、又はフェニレン基で置き換えられた２価の有機基を表す。また、フェニレン基上の任意の水素原子は１価の有機基で置き換えられてもよい。
Ｔ_３は、－ＣＨ_２－、－ＣＨ（ＣＨ_３）－、－Ｃ（ＣＨ_３）_２－、－（ＣＨ_２）_ｎ－（ｎは２～１８の整数）、フェニレン基、又は上記－（ＣＨ_２）_ｎ－の任意のＣＨ_２が、－Ｏ－、－ＣＨ（ＣＨ_３）－、－Ｃ（ＣＨ_３）_２－、－ＣＯＮＲ－（Ｒは水素原子又はメチル基を表す。）、－ＮＲＣＯＮＲ－（Ｒは水素原子又はメチル基を表す。）、フェニレン基で置き換えられた２価の有機基を表す。ｎ１は、１～３の整数を表す。ｎ３は０～１の整数を表す。

Ｒ_１、Ｒ_２、Ｒ_３、Ｒ_４はそれぞれ独立して、水素原子又はメチル基を表す。＊１は結合手を表し、＊２は炭素原子と結合する結合手を表す。

Q _2a , Q _2b , Q _3a and Q _3b each independently represent a monovalent organic group selected from the following formulas (Q-1) to (Q-17): provided that when S ₂₂ and S ₃₂ are each a single bond, Q _2a and Q _3a represent a monovalent organic group selected from (Q-1), (Q-3), (Q-7) to (Q-13) or (Q-17).
l ₂ and l ₃ each independently represent an integer of 1 or 2.
m ₁ represents an integer of 1 or 2, and multiple m ₁ may be the same or different. m _2a and m _2b each independently represent an integer of 1 or 2.

M represents a divalent organic group selected from the following formulae (M-1) to (M-11): _{R 1} and R ₂ each independently represent a hydrogen atom or a methyl group. T ₁ and T ₂ each independently represent a single bond, -O-, -NR- (R represents a hydrogen atom or a methyl group), -CONR- (R represents a hydrogen atom or a methyl group), -NRCONR- (R represents a hydrogen atom or a methyl group), a phenylene group, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -(CH ₂ ) _n - (n is an integer from 2 to 20), or a divalent organic group in which any CH ₂ in the above-(CH ₂ ) _n - is replaced by -CH(CH ₃ )-, -C(CH ₃ ) ₂ -), -O-, -NR- (R represents a hydrogen atom or a methyl group), -CONR- (R represents a hydrogen atom or a methyl group), -NRCONR- (R represents a hydrogen atom or a methyl group), or a phenylene group. In addition, any hydrogen atom on the phenylene group may be replaced with a monovalent organic group.
_T3 represents _-CH2- , -CH( _CH3 )-, -C( _CH3 ) _2- , -( _CH2 ) _n- (n is an integer from 2 to 18), a phenylene group, or a divalent organic group in which _{any CH2} in the -( _CH2 ) _n- is replaced by -O-, -CH( _CH3 )-, -C( _CH3 ) _2- , -CONR- (R represents a hydrogen atom or a methyl group), -NRCONR- (R represents a hydrogen atom or a methyl group) or a phenylene group. n1 represents an integer from 1 to 3. n3 represents an integer from 0 to 1.

R ₁ , R ₂ , R ₃ and R ₄ each independently represent a hydrogen atom or a methyl group. *1 represents a bond, and *2 represents a bond bonded to a carbon atom.

*1 represents a bond bonded to a nitrogen atom or (Q _2b ), and *2 represents a bond bonded to a benzene ring. n represents an integer of 1 to 2. _{A L11} and A _L12 each independently represent a single bond, -O-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -(CH ₂ ) _n - (n represents an integer of 2 to 20), -COO-, -OCO-, -CONR- (R represents a hydrogen atom or a methyl group), or a divalent organic group in which any CH ₂ in the -(CH ₂ ) _n - is replaced by -O-, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -COO-, -OCO-, or -CONR- (R represents a hydrogen atom or a methyl group). When a plurality of A _L12 are present, the plurality of A _L12 may be the same or different. _{A S11} and A _S21 each independently represent a single bond, -O-, -CO-, -CH ₂ -, -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -(CH ₂ ) _n - (n represents an integer of 2 to 20), a phenylene group, or a divalent organic group in which any CH ₂ in the -(CH ₂ ) _n - is replaced by -CH(CH ₃ )-, -C(CH ₃ ) ₂ -, -O-, -CO-, or a phenylene group. R _L represents a hydrogen atom, a hydroxyl group, or a methyl group. p represents an integer of 1 to 2.

R ₁ , R ₃ , R ₇ and R ₈ each represent a hydrogen atom or a methyl group. R ₁₆ and R ₁₇ each represent a phenyl group. *1 represents a bond, and *2 represents a bond bonded to a carbon atom.
The hydrogen atom on the phenylene group in _L1 may be replaced by a monovalent organic group such as an alkyl group having 1 to 5 carbon atoms, such as a methyl group or an ethyl group; an alkoxy group having 1 to 5 carbon atoms, such as a methoxy group; a halogen atom, such as a fluorine atom; a halogenated alkyl group having 1 to 5 carbon atoms, such as a trifluoromethyl group _{; -NR1R2} ( _R1 and _R2 each represent a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), a cyano group, or a hydroxyl group.

In the divalent organic groups represented by the above formulas (M-1) to (M-11) and the monovalent organic groups represented by the above formulas (Q-1) to (Q-17), any hydrogen atom on the benzene ring or heterocycle may be replaced with a monovalent organic group, and specific examples of such monovalent organic groups include the structures exemplified as the monovalent organic group substituting a hydrogen atom on the phenylene group in the above _L1 .
In the above formula (B1), from the viewpoint of ease of synthesis, L ₁ may be any of the following formulae (L1-a-1) to (L1-a-12), (L1-b-1) to (L1-b-3), or (L1-c-1) to (L1-c-3).

From the viewpoint of ease of synthesis, A _L11 and A _L12 are preferably a single bond, -O-, -CH ₂ -, -(CH ₂ ) _n - (n represents an integer of 2 to 20), -COO-, -OCO-, -CONR- (R represents a hydrogen atom or a methyl group), or a divalent organic group in which any CH ₂ in the -(CH ₂ ) _n - is replaced by -O- or -CONR- (R represents a hydrogen atom or a methyl group).
From the viewpoint of ease of synthesis, the above S _21a may be represented by any of the following formulae (S _21a -1-1) to (S _21a -1-5) or (S _21a -2-1).

*1 represents a bond bonded to the nitrogen atom, and *2 represents a bond bonded to the benzene ring.
From the viewpoint of ease of synthesis, the above S _21b may be represented by the above formulae (S _21a -1-1) to (S _{21a -1-5} ), (S _21a -2-1), or the following formula (S _21b -1-1), in which *1 represents a bond bonded to (Q _{2b )} , and *2 represents a bond bonded to _the benzene ring.

＊１は、窒素原子と結合する結合手を表し、＊２はベンゼン環と結合する結合手を表す。Ｍは上記式（Ｍ－１）～（Ｍ－１０）から選ばれる基を表す。
上記Ｓ_３１ｂは、合成が容易である観点から、中でも単結合、－Ｏ－、上記式（Ｓ_３１ａ－１）～（Ｓ_３１ａ－５）、下記式（Ｓ_３１ｂ－１）～（Ｓ_３１ｂ－５）としてもよい。但し、上記式（Ｓ_３１ａ－１）～（Ｓ_３１ａ－５）において、＊１は、（Ｑ_３ｂ）と結合する結合手を表し、＊２はベンゼン環と結合する結合手を表す。

*1 represents a bond bonding to a nitrogen atom or (Q _2b ), and *2 represents a bond bonding to a benzene ring.
From the viewpoint of ease of synthesis, the above S _31a may be a single bond or any of the following formulae (S _31a -1) to (S _31a -5).

*1 represents a bond bonded to a nitrogen atom, *2 represents a bond bonded to a benzene ring, and M represents a group selected from the above formulas (M-1) to (M-10).
From the viewpoint of ease of synthesis, S _31b may be a single bond, —O—, the above formulae (S _{31a -1) to (S 31a -5), or the following formulae (S 31b -1 ) to (S 31b -5 )} , where *1 represents a bond bonded to (Q _3b ), and *2 represents a bond bonded to the benzene ring.

*1 represents a bond bonded to Q _3b , *2 represents a bond bonded to the benzene ring, M represents a group selected from the above formulae (M-1) to (M-10), and Q _3b has the same meaning as the above formula (B3-2).
From the viewpoint of ease of synthesis, R ₃₃ may be a hydrogen atom, a methyl group, or an ethyl group.
Preferred specific examples of compound (B) include compounds represented by the following formulas (B1-1-1) to (B1-1-4), (B1-2-1) to (B1-2-2), (B1-3-1) to (B1-3-26), (B2-1-1) to (B2-1-2), (B2-2-1) to (B2-2-18), (B3-1-1) to (B3-1-7), (B3-2-1) to (B3-2-11), and (B3-3-1).

The preferred content of compound (B) is 0.1 to 40 parts by mass, more preferably 0.5 to 35 parts by mass, and even more preferably 0.5 to 30 parts by mass per 100 parts by mass of component (A).

<Method of producing polyamic acid>
The polymer (A) in the present invention can be obtained, for example, by reacting a tetracarboxylic acid derivative having the above structure of _X1 with a diamine having the above structure of _Y1 by a known method such as that described in International Publication WO2013/157586.

[Terminal Modifier]
In synthesizing the polymer (A) in the present invention, a terminal-modified polymer may be synthesized by using a suitable terminal-capping agent together with the above-mentioned tetracarboxylic acid derivative and diamine.

二炭酸ジ－ｔｅｒｔ－ブチル、二炭酸ジアリルなどの二炭酸ジエステル化合物；アクリロイルクロリド、メタクリロイルクロリド、ニコチン酸クロリドなどのクロロカルボニル化合物；アニリン、２－アミノフェノール、３－アミノフェノール、４－アミノサリチル酸、５－アミノサリチル酸、６－アミノサリチル酸、２－アミノ安息香酸、３－アミノ安息香酸、４－アミノ安息香酸、シクロヘキシルアミン、ｎ－ブチルアミン、ｎ－ペンチルアミン、ｎ－ヘキシルアミン、ｎ－ヘプチルアミン、ｎ－オクチルアミンなどのモノアミン化合物；エチルイソシアネート、フェニルイソシアネート、ナフチルイソシアネートなどのモノイソシアネート化合物などを挙げることができる。 Examples of the terminal modifier include acid monoanhydrides such as maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, compounds represented by the following formulas (m-1) to (m-6), 3-(3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, and 4-ethynylphthalic anhydride;

Examples of the dicarbonate diester compounds include di-tert-butyl dicarbonate and diallyl dicarbonate; chlorocarbonyl compounds include acryloyl chloride, methacryloyl chloride and nicotinic acid chloride; monoamine compounds include aniline, 2-aminophenol, 3-aminophenol, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine and n-octylamine; and monoisocyanate compounds include ethyl isocyanate, phenyl isocyanate and naphthyl isocyanate.

The proportion of terminal modifier used is preferably 20 molar parts or less, and more preferably 10 molar parts or less, per 100 molar parts of the total diamine used.

<Liquid crystal alignment agent>
The liquid crystal aligning agent of the present invention may contain other polymers in addition to the polymer (A). Examples of the other polymers include polyesters, polyamides, polyureas, polyorganosiloxanes, cellulose derivatives, polyacetals, polystyrene or its derivatives, poly(styrene-phenylmaleimide) derivatives, and poly(meth)acrylates. From the viewpoint of ease of synthesis, it is preferable that the polyorganosiloxane has at least one of an oxetanyl group and an oxiranyl group.

The liquid crystal alignment agent is used to prepare a liquid crystal alignment film, and takes the form of a coating liquid from the viewpoint of forming a uniform thin film. The liquid crystal alignment agent of the present invention is also preferably a coating liquid containing the above-mentioned polymer component and an organic solvent. In this case, the concentration of the polymer in the liquid crystal alignment agent can be appropriately changed depending on the thickness of the coating film to be formed. From the viewpoint of forming a uniform and defect-free coating film, 1% by mass or more is preferable, and from the viewpoint of storage stability of the solution, 10% by mass or less is preferable. A particularly preferable polymer concentration is 2 to 8% by mass.

The organic solvent contained in the liquid crystal alignment agent is not particularly limited as long as the polymer component is dissolved uniformly. Specific examples include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylsulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, N,N-dimethyllactamide, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide (collectively referred to as "good solvents"). From the viewpoint of good printability, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, N,N-dimethyllactamide, or γ-butyrolactone may be used. From the viewpoint of good printability, the good solvent in the liquid crystal aligning agent of the present invention may be 20 to 99 mass %, or 20 to 90 mass %, or 30 to 80 mass % of the total solvent contained in the liquid crystal aligning agent.

In addition, the organic solvent contained in the liquid crystal alignment agent is preferably a mixed solvent containing a solvent (also called a poor solvent) that improves the coating property and the surface smoothness of the coating film when applying the liquid crystal alignment agent in addition to the above-mentioned solvent. Specific examples of the organic solvent to be used in combination are listed below, but are not limited to these examples.
For example, diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxy)-2-propanol, diethoxy)-1-propanol, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, ethylene glycol monoacetate, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol acetate, propylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), and the like.

Among these, from the viewpoint of good printability, the following poor solvents may be used: diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, and diisobutyl ketone.

From the viewpoint of good printability, the combinations of good and poor solvents are N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether and 2,6- Examples of the combinations include dimethyl-4-heptanone, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisopropyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and 2,6-dimethyl-4-heptanol, N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether, N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether, and N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether. These poor solvents may be 1 to 80% by mass, 10 to 80% by mass, or 20 to 70% by mass of the entire solvent contained in the liquid crystal alignment agent. The type and content of such a solvent are appropriately selected depending on the coating device, coating conditions, and coating environment of the liquid crystal alignment agent.

The liquid crystal alignment agent of the present invention may contain additional components other than the polymer component, component (B), and organic solvent. Such additional components include adhesion assistants for improving the adhesion between the liquid crystal alignment film and the substrate or between the liquid crystal alignment film and the sealant, compounds for increasing the strength of the liquid crystal alignment film (hereinafter also referred to as cross-linking compounds), dielectrics and conductive substances for adjusting the dielectric constant and electrical resistance of the liquid crystal alignment film, etc.

式中、Ｒ_１は、水素原子、炭素数１～３のアルキル基又は「＊－ＣＨ_２－ＯＨ」であり、Ｒ_２及びＲ_３は、それぞれ独立に水素原子、炭素数１～３のアルキル基又は「＊－ＣＨ_２－ＯＨ」である。＊は結合手であることを示す。

As the crosslinkable compound, from the viewpoints of less generation of afterimages and a high effect of improving film strength, a compound having at least one group selected from the group consisting of an oxiranyl group, an oxetanyl group, a protected isocyanate group, a protected isothiocyanate group, a group containing an oxazoline ring structure, a group containing a Meldrum's acid structure, a cyclocarbonate group, and a group represented by the following formula (d), or a compound selected from the compounds represented by the following formulas (e-1) to (e-8) (hereinafter, these are also collectively referred to as compound (C)).

In the formula, R ₁ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ₂ -OH", and R ₂ and R ₃ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ₂ -OH". * indicates a bond.

Specific examples of the compound having an oxiranyl group include compounds having two or more oxiranyl groups, such as the compounds described in paragraph [0037] of JP-A-10-338880 and compounds having a triazine ring skeleton described in International Publication WO2017/170483. Among these, from the viewpoint of a high crosslinking effect, compounds containing nitrogen atoms, such as N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-p-phenylenediamine, and compounds represented by the following formulas (r-1) to (r-3), may be used.

Specific examples of compounds having an oxetanyl group include compounds having two or more oxetanyl groups, such as those described in paragraphs [0170] to [0175] of International Publication No. 2011/132751.

Specific examples of the compound having a protected isocyanate group include compounds having two or more protected isocyanate groups described in paragraphs [0046] to [0047] of JP 2014-224978 A, compounds having three or more protected isocyanate groups described in paragraphs [0119] to [0120] of WO 2015/141598, etc. Among these, compounds represented by the following formulae (bi-1) to (bi-3) may be used from the viewpoint of a high crosslinking effect.

Specific examples of compounds having a protected isothiocyanate group include compounds having two or more protected isothiocyanate groups, as described in JP 2016-200798 A.

Specific examples of compounds having a group containing an oxazoline ring structure include compounds containing two or more oxazoline structures, as described in paragraph [0115] of JP 2007-286597 A.

Specific examples of compounds having a group containing a Meldrum's acid structure include compounds having two or more Meldrum's acid structures, as described in International Publication WO 2012/091088.

Specific examples of compounds having a cyclocarbonate group include the compounds described in International Publication WO2011/155577.

Examples of the alkyl group having 1 to 3 carbon atoms for R ₁ , R ₂ and R ₃ in the group represented by formula (d) above include a methyl group, an ethyl group and a propyl group.

Specific examples of the compound having a group represented by the above formula (d) include compounds having two or more groups represented by the above formula (d) described in International Publication WO2015/072554 and paragraph [0058] of JP2016-118753A, compounds described in JP2016-200798A, etc. Among these, compounds represented by the following formulas (hd-1) to (hd-8) may be used from the viewpoint of a high crosslinking effect.

The above compounds are examples of crosslinkable compounds, and are not limited thereto. For example, components other than those described above disclosed on pages 53 [0105] to 55 [0116] of International Publication No. 2015/060357 can be mentioned. The crosslinkable compound contained in the liquid crystal aligning agent of the present invention may be one type, or two or more types may be combined.
The content of the crosslinkable compound in the liquid crystal aligning agent of the present invention may be 0.5 to 20 parts by mass, or 1 to 15 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent, from the viewpoint of proceeding with the crosslinking reaction to exhibit the intended effect and enhancing the liquid crystal alignment property.

Examples of the adhesion aids include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, and N-ethoxycarbonyl-3-aminopropyltrimethoxysilane. N-trimethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltriethoxysilane Aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis(oxyethylene)-3-aminopropyltrimethoxysilane, N-bis(oxyethylene)-3-aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane Examples of silane coupling agents include silane coupling agents such as xysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanatepropyltriethoxysilane. When using these silane coupling agents, from the viewpoint of enhancing the liquid crystal alignment property, the amount may be 0.1 to 30 parts by mass, or 0.1 to 20 parts by mass, relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent.

<Liquid crystal alignment film/Liquid crystal display element>
By using the liquid crystal alignment agent, a liquid crystal alignment film can be manufactured. Also, a liquid crystal display element according to the present invention includes a liquid crystal alignment film formed by using the liquid crystal alignment agent. The operation mode of the liquid crystal display element according to the present invention is not particularly limited, and it can be applied to various operation modes such as TN (Twisted Nematic) type, STN type, vertical alignment type (including VA-MVA type, VA-PVA type, etc.), in-plane switching type (IPS type), FFS (Fringe Field Switching) type, and optical compensation bend type (OCB type).

The liquid crystal display element according to the present invention can be manufactured, for example, by a process including the following steps (1-1) to (1-3). In step (1-1), different substrates are used depending on the desired operation mode. Steps (1-2) and (1-3) are common to each operation mode.

[Step (1-1): Formation of coating film]
First, the liquid crystal aligning agent of the present invention is applied onto a substrate, and then the applied surface is heated to form a coating film on the substrate.

(1-1A)
For example, when manufacturing a TN-type, STN-type or VA-type liquid crystal display element, first, two substrates each having a patterned transparent conductive film are used as a pair, and the liquid crystal alignment agent prepared above is applied to each of the transparent conductive film-formed surfaces, preferably by offset printing, spin coating, roll coating or inkjet printing. As the substrate, for example, a transparent substrate made of glass such as float glass or soda glass; or a plastic such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate or poly(alicyclic olefin) can be used. As the transparent conductive film provided on one side of the substrate, a NESA film (registered trademark of PPG, USA) made of tin oxide (SnO ₂ ), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) or the like can be used. To obtain a patterned transparent conductive film, for example, a method of forming a pattern by photo-etching after forming a patternless transparent conductive film; a method of using a mask having a desired pattern when forming a transparent conductive film; or the like can be used. When applying the liquid crystal alignment agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film, the surface of the substrate on which the coating film is to be formed may be pretreated by applying a functional silane compound, a functional titanium compound, or the like.

After applying the liquid crystal alignment agent, pre-heating (pre-baking) is preferably performed for the purpose of preventing dripping of the applied liquid crystal alignment agent. The pre-baking temperature is preferably 30 to 200°C, more preferably 40 to 150°C, and particularly preferably 40 to 100°C. The pre-baking time is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes. Thereafter, a baking (post-baking) process is performed for the purpose of completely removing the solvent and thermally imidizing the amic acid structure present in the polymer as necessary. The baking temperature (post-baking temperature) at this time is preferably 80 to 300°C, more preferably 120 to 250°C. The post-baking time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The film thickness of the film thus formed is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

(1-1B)
When manufacturing an IPS or FFS type liquid crystal display element, a liquid crystal alignment agent is applied to the electrode forming surface of a substrate on which an electrode made of a transparent conductive film or a metal film patterned into a comb-tooth shape is provided, and to one surface of an opposing substrate on which no electrode is provided, and then each applied surface is heated to form a coating film. The materials of the substrate and transparent conductive film used in this case, the coating method, the heating conditions after coating, the patterning method of the transparent conductive film or the metal film, the pretreatment of the substrate, and the preferred thickness of the coating film to be formed are the same as those in (1-1A) above. As the metal film, for example, a film made of a metal such as chromium can be used.

In both of the above cases (1-1A) and (1-1B), a liquid crystal alignment film or a coating film that will become a liquid crystal alignment film is formed by applying the liquid crystal alignment agent onto a substrate and then removing the organic solvent. At this time, the coating film may be further heated after formation to advance the dehydration ring-closing reaction of the polyamic acid, polyamic acid ester, and polyimide blended in the liquid crystal alignment agent according to the present invention, resulting in a more imidized coating film.

[Step (1-2): Treatment for imparting alignment ability]
When a TN-type, STN-type, IPS-type or FFS-type liquid crystal display element is manufactured, a treatment for imparting liquid crystal alignment ability to the coating film formed in the above step (1-1) is carried out. As a result, the alignment ability of liquid crystal molecules is imparted to the coating film, forming a liquid crystal alignment film. Examples of the alignment ability imparting treatment include a rubbing treatment in which the coating film is rubbed in a certain direction with a roll wrapped with a cloth made of fibers such as nylon, rayon or cotton, and a photoalignment treatment in which the coating film is irradiated with polarized or non-polarized radiation. On the other hand, when a VA-type liquid crystal display element is manufactured, the coating film formed in the above step (1-1) can be used as it is as a liquid crystal alignment film, but the coating film may also be subjected to an alignment ability imparting treatment.

When the coating film is provided with liquid crystal alignment ability by photoalignment treatment, the radiation to be irradiated to the coating film is, for example,
For example, ultraviolet light and visible light including light with wavelengths of 150 to 800 nm can be used. When the radiation is polarized, it may be linearly polarized or partially polarized. When the radiation used is linearly polarized or partially polarized, irradiation may be performed from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these. When irradiating with unpolarized radiation, the direction of irradiation is an oblique direction.

Examples of light sources that can be used include low-pressure mercury lamps, high-pressure mercury lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, and excimer lasers. Ultraviolet rays in a preferred wavelength range can be obtained by using a light source in combination with, for example, a filter, a diffraction grating, etc. The radiation dose is preferably 10 to 5,000 mJ/ ^cm2 , and more preferably 30 to 2,000 mJ/ ^cm2 .
The coating film may be irradiated with light while being heated in order to enhance the reactivity. The temperature during heating is usually 30 to 250° C., preferably 40 to 200° C., and more preferably 50 to 150° C.

When ultraviolet light containing light with a wavelength of 150 to 800 nm is used, the light-irradiated film obtained in the above process can be used as it is as a liquid crystal alignment film, but the light-irradiated film may be baked, washed with water or an organic solvent, or a combination of these. The baking temperature in this case is preferably 80 to 300°C, more preferably 80 to 250°C. The baking time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The baking may be performed once or twice or more times. The light alignment treatment here corresponds to the treatment of light irradiation in a state where the film is not in contact with the liquid crystal layer.

The organic solvent used for the above cleaning is not particularly limited, but specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, or cyclohexyl acetate.

In addition, the liquid crystal alignment film after the rubbing process may be further subjected to a process of changing the pretilt angle of a part of the liquid crystal alignment film by irradiating a part of the liquid crystal alignment film with ultraviolet light, or a process of forming a resist film on a part of the liquid crystal alignment film surface, performing a rubbing process in a direction different from the previous rubbing process, and then removing the resist film, so that the liquid crystal alignment film has different liquid crystal alignment capabilities for each region. In this case, it is possible to improve the visibility characteristics of the resulting liquid crystal display element. The liquid crystal alignment film suitable for VA-type liquid crystal display elements can also be suitably used for PSA (polymer sustained alignment)-type liquid crystal display elements.

[Step (1-3): Construction of liquid crystal cell]
(1-3A)
Two substrates on which a liquid crystal alignment film is formed as described above are prepared, and liquid crystal is disposed between the two substrates arranged opposite to each other to manufacture a liquid crystal cell. For example, the following two methods can be mentioned for manufacturing a liquid crystal cell. The first method is a method that has been known for a long time. First, two substrates are arranged opposite to each other with a gap (cell gap) so that the respective liquid crystal alignment films face each other, and the peripheries of the two substrates are bonded together with a sealant, and liquid crystal is injected and filled into the cell gap partitioned by the substrate surfaces and the sealant, and then the injection hole is sealed to manufacture a liquid crystal cell. The second method is a method called the ODF (One Drop Fill) method. For example, a sealant that is ultraviolet light curable is applied to a predetermined location on one of the two substrates on which a liquid crystal alignment film is formed, and liquid crystal is further dropped at several predetermined locations on the liquid crystal alignment film surface, and then the other substrate is bonded so that the liquid crystal alignment film faces each other, and the liquid crystal is spread over the entire surface of the substrate, and then ultraviolet light is irradiated to the entire surface of the substrate to cure the sealant, thereby manufacturing a liquid crystal cell. Regardless of which method is used, it is desirable to further heat the liquid crystal cell produced as described above to a temperature at which the liquid crystal used assumes an isotropic phase, and then slowly cool it to room temperature to remove the flow orientation that occurs during liquid crystal filling.

As a sealing agent, for example, an epoxy resin containing a hardener and aluminum oxide spheres as spacers can be used.

Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals, of which nematic liquid crystals are preferred. For example, Schiff base liquid crystals, azoxy liquid crystals, biphenyl liquid crystals, phenylcyclohexane liquid crystals, ester liquid crystals, terphenyl liquid crystals, biphenylcyclohexane liquid crystals, pyrimidine liquid crystals, dioxane liquid crystals, bicyclooctane liquid crystals, and cubane liquid crystals can be used. In addition, these liquid crystals may be used by adding cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonaate, and cholesteryl carbonate; chiral agents such as those sold under the trade names "C-15" and "CB-15" (manufactured by Merck); and ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate. The liquid crystal may also contain an anisotropic dye. The term "dye" may mean a material capable of intensively absorbing or transforming light in at least a part or the entire range within the visible light region, for example, a wavelength range of 400 nm to 700 nm, and the term "anisotropic dye" may mean a material capable of anisotropically absorbing light in at least a part or the entire range of the visible light region. The color of the liquid crystal cell can be adjusted by using such dyes. The type of anisotropic dye is not particularly limited, and for example, a black dye or a color dye can be used. The ratio of the anisotropic dye to the liquid crystal is appropriately selected within a range that does not impair the desired physical properties, and for example, the anisotropic dye may be included in a ratio of 0.01 to 5 parts by weight with respect to 100 parts by weight of the liquid crystal compound, but the ratio may be changed to an appropriate range as necessary.

その後、一対の基板の有する導電膜間に電圧を印加した状態で液晶セルに光照射する。ここで印加する電圧は、例えば５～５０Ｖの直流又は交流とすることができる。また、照射する光としては、例えば１５０～８００ｎｍの波長の光を含む紫外線及び可視光線を用いることができるが、３００～４００ｎｍの波長の光を含む紫外線が好ましい。照射光の光源としては、例えば低圧水銀ランプ、高圧水銀ランプ、重水素ランプ、メタルハライドランプ、アルゴン共鳴ランプ、キセノンランプ、エキシマレーザーなどを使用することができる。なお、上記の好ましい波長領域の紫外線は、光源を、例えばフィルター回折格子などと併用する手段などにより得ることができる。光の照射量としては、好ましくは１００ｍＪ／ｃｍ^２以上３０，０００ｍＪ／ｃｍ^２未満であり、より好ましくは１００～２０，０００ｍＪ／ｃｍ^２である。 (1-3B)
In the case of producing a PSA type liquid crystal display element, a liquid crystal cell is constructed in the same manner as in (1-3A) above, except that a photopolymerizable compound such as any of the following formulae (w-1) to (w-5) is injected or dropped together with the liquid crystal.

Thereafter, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates. The voltage applied here can be, for example, 5 to 50 V DC or AC. The light to be irradiated can be, for example, ultraviolet light and visible light containing light with a wavelength of 150 to 800 nm, but ultraviolet light containing light with a wavelength of 300 to 400 nm is preferred. The light source for the irradiation light can be, for example, a low pressure mercury lamp, a high pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, or the like. The ultraviolet light in the above preferred wavelength range can be obtained by using the light source in combination with, for example, a filter diffraction grating. The amount of light irradiation is preferably 100 mJ/cm ² or more and less than 30,000 mJ/cm ² , more preferably 100 to 20,000 mJ/cm ² .

(1-3C)
When a coating film is formed on a substrate using a liquid crystal alignment agent containing a compound (polymer or additive) having a photopolymerizable group, a liquid crystal cell is constructed in the same manner as in (1-3A) above, and then, a liquid crystal display element is manufactured by going through a process of irradiating the liquid crystal cell with light while applying a voltage between the conductive films of a pair of substrates. According to this method, the merits of the PSA mode can be realized with a small amount of light irradiation. Examples of additives having a photopolymerizable group include the structures exemplified by the above formulas (w-1) to (w-5), and the blending amount may be 1 to 30% by mass, 1 to 20% by mass, or 1 to 15% by mass with respect to the total solid content of the polymer contained in the liquid crystal alignment agent. The light irradiation to the liquid crystal cell may be performed in a state where the liquid crystal is driven by applying a voltage, or may be performed in a state where a low voltage that does not drive the liquid crystal is applied. The voltage to be applied may be, for example, 0.1 to 30 V of direct current or alternating current. The conditions of the light to be irradiated can be the same as those described in (1-3B) above. The light irradiation treatment here corresponds to the light irradiation treatment in a state of contact with the liquid crystal layer.

The liquid crystal display element according to the present invention can be obtained by attaching a polarizing plate to the outer surface of the liquid crystal cell. Examples of the polarizing plate to be attached to the outer surface of the liquid crystal cell include a polarizing film called an "H film" made by absorbing iodine while stretching and aligning polyvinyl alcohol, sandwiched between cellulose acetate protective films, and a polarizing plate made of the H film itself.
The liquid crystal display element according to the present invention can be effectively applied to various devices, and can be used in various display devices such as watches, portable games, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, various monitors, liquid crystal televisions, and information displays.
As described above, by using the liquid crystal aligning agent of the present invention, it is possible to obtain a liquid crystal alignment film that generates little residual images and can minimize bright spots even when physical friction occurs, such as rubbing with a spacer, and a liquid crystal display element having the same. In addition, the obtained liquid crystal display element has high reliability.

Ｂｏｃは、ｔｅｒｔ－ブトキシカルボニル基を表す。 The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. The abbreviations of the compounds and the measurement methods of the respective properties are as follows. Compound (c-2) was synthesized according to the method described in Synthesis Example 3 of JP-A-2008-052260.
(Diamine)
DA-1 to DA-27: Compounds represented by the following formulas (DA-1) to (DA-27) (tetracarboxylic dianhydrides)
CA-1 to CA-8: Compounds represented by the following formulas (CA-1) to (CA-8) (tetracarboxylic acid diester dihalides)
CE-1: Compound represented by the following formula (CE-1) (monocarboxylic acid chloride)
E-1: Acryloyl chloride (additive)
b-1 to b-9: Compounds represented by the following formulas (b-1) to (b-9) (other additives)
c-1: Compound represented by the following formula (c-1) c-2: Compound represented by the following formula (c-2) F-1: N-α-(9-fluorenylmethyloxycarbonyl)-N-τ-t-butoxycarbonyl-L-histidine (compound represented by the following formula (F-1))
s-1: 3-glycidoxypropyltriethoxysilane (compound represented by the following formula (s-1))
s-2: 3-glycidoxypropylmethyldiethoxysilane (compound represented by the following formula (s-2))
M-1: 3-picolylamine (organic solvent)
NMP: N-methyl-2-pyrrolidone, GBL: γ-butyrolactone,
BCS: butyl cellosolve, DIBK: diisobutyl ketone,
NEP: N-ethyl-2-pyrrolidone, DAA: diacetone alcohol, PC: propylene carbonate, DME: dipropylene glycol dimethyl ether,
DPM: dipropylene glycol monomethyl ether,
PB: propylene glycol monobutyl ether,
PGDAC: propylene glycol diacetate,
DEDE: diethylene glycol diethyl ether,
GVL: γ-valerolactone, DML: N,N-dimethyllactamide EEP: 3-ethoxyethyl propionate

Boc represents a tert-butoxycarbonyl group.

Boc represents a tert-butoxycarbonyl group. Fmoc represents a 9-fluorenylmethyloxycarbonyl group.
[viscosity]
The viscosity of the solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample amount of 1.1 mL, a cone rotor TE-1 (1°34′, R24), and a temperature of 25°C.
[Molecular weight]
The molecular weight was measured by a GPC (gel permeation chromatography) device, and the number average molecular weight (Mn) and weight average molecular weight (Mw) were calculated as values calculated in terms of polyethylene glycol and polyethylene oxide.
GPC apparatus: Shodex (GPC-101), column: Shodex (KD803, KD805 in series), column temperature: 50°C, eluent: N,N-dimethylformamide (additives: lithium bromide monohydrate (LiBr.H ₂ O) 30 mmol/L, phosphoric acid anhydrous crystal (o-phosphoric acid) 30 mmol/L, tetrahydrofuran (THF) 10 mL/L), flow rate: 1.0 mL/min. Standard samples for creating calibration curves: TSK standard polyethylene oxide (weight average molecular weight (Mw) about 900,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation, and polyethylene glycol (peak top molecular weight (Mp) about 12,000, 4,000, 1,000) manufactured by Polymer Laboratory. In order to avoid overlapping peaks, two samples, a mixture of four types of 900,000, 100,000, 12,000, and 1,000, and a mixture of three types of 150,000, 30,000, and 4,000, were measured separately.

<Measurement of imidization rate>
20 mg of polyimide powder was placed in an NMR sample tube (NMR sampling tube standard, φ5 (Kusano Scientific Co., Ltd.)), deuterated dimethyl sulfoxide (DMSO-d6, 0.05% TMS (tetramethylsilane) mixture) (0.53 mL) was added, and the mixture was sonicated to completely dissolve. This solution was measured for proton NMR at 500 MHz using an NMR measurement device (JNW-ECA500) (JEOL Datum Co., Ltd.). The imidization rate was calculated by the following formula, using a proton derived from a structure that does not change before and after imidization as a reference proton, and the peak integrated value of this proton and the proton peak integrated value derived from the NH group of the amic acid that appears around 9.5 ppm to 10.0 ppm.
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 the amic acid, y is the integrated value of the peak of the reference proton, and α is the ratio of the number of reference protons to one NH group proton of the amic acid in the case of polyamic acid (imidization rate 0%).

ナスフラスコに、２，５－ピリジンジカルボン酸（３．００ｇ、１８．０ｍｍｏｌ）、４－アミノフェノール（４．１１ｇ、３７．７ｍｍｏｌ）及びＮ，Ｎ－ジメチルホルムアミド（ＤＭＦ）（１００ｇ）を加えて、混合物を室温で撹拌した。次に、Ｎ－エチルモルホリン（４．３４ｇ、３７．７ｍｍｏｌ）及び４－（４，６－ジメトキシ－１，３，５－トリアジン－２－イル）－４－メチルモルホリニウムクロリド（ＤＭＴ－ＭＭ）（１０．４３ｇ、３７．７ｍｍｏｌ）を加えて、室温で一晩撹拌した。反応溶液に水（６００ｇ）を加えて、固体を析出させ、得られた固体をメタノールで洗浄した。次に、溶媒を減圧留去して化合物（ｂ－１－１）を４．２３ｇ得た。
４つ口フラスコに化合物（ｂ－１－１）（２．００ｇ、５．７２ｍｍｏｌ）、２４％水酸化ナトリウム水溶液（３．８１ｇ、２２．８ｍｍｏｌ）及び純水（１．１６ｇ）を加えて、室温下において、撹拌下に、３７％ホルムアルデヒド水溶液（４．６８ｇ、５７．２ｍｍｏｌ）を滴下して反応させた。反応溶液を３５～４０℃に昇温して撹拌した後、反応溶液の一部を取り出してＬＣ／ＭＳを測定し、原料のピークが消失したことより反応の終点を確認した。反応終了後、得られた反応混合物を酢酸で中和し、この後、２時間撹拌して、析出した結晶を濾過した。溶媒を減圧留去して化合物（ｂ－１）を２．４１ｇ得た。 [Synthesis of compound (B)]
<Synthesis example (b-1)>
Compound (b-1) was synthesized according to the route shown below.

2,5-pyridinedicarboxylic acid (3.00 g, 18.0 mmol), 4-aminophenol (4.11 g, 37.7 mmol) and N,N-dimethylformamide (DMF) (100 g) were added to a recovery flask, and the mixture was stirred at room temperature. Next, N-ethylmorpholine (4.34 g, 37.7 mmol) and 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) (10.43 g, 37.7 mmol) were added, and the mixture was stirred at room temperature overnight. Water (600 g) was added to the reaction solution to precipitate a solid, and the obtained solid was washed with methanol. Next, the solvent was distilled off under reduced pressure to obtain 4.23 g of compound (b-1-1).
Compound (b-1-1) (2.00 g, 5.72 mmol), 24% aqueous sodium hydroxide solution (3.81 g, 22.8 mmol) and pure water (1.16 g) were added to a four-neck flask, and 37% aqueous formaldehyde solution (4.68 g, 57.2 mmol) was added dropwise under stirring at room temperature to cause a reaction. The reaction solution was heated to 35-40° C. and stirred, and then a portion of the reaction solution was taken out and measured by LC/MS. The end point of the reaction was confirmed by the disappearance of the peak of the raw material. After the reaction was completed, the obtained reaction mixture was neutralized with acetic acid, and then stirred for 2 hours, and the precipitated crystals were filtered. The solvent was distilled off under reduced pressure to obtain 2.41 g of compound (b-1).

<Synthesis example (b-2)>
Compound (b-2) was obtained by synthesizing in the same manner as in Scheme 1, except that 4-aminophenol was changed to tyramine.

ナスフラスコに４，４’－ジメトキシジフェニルアミン（３．００ｇ、１３．１ｍｍｏｌ）、炭酸カリウム（５．４３ｇ、３９．３ｍｍｏｌ）及びＮ，Ｎ－ジメチルホルムアミド（ＤＭＦ）（１８．６ｇ）を加えて、混合物を室温で撹拌した。次に、ヨードメタン（７．４３ｇ、５２．３ｍｍｏｌ）を加え、４０～５０℃に昇温して撹拌した後、反応溶液の一部を取り出してＬＣ／ＭＳを測定し、原料のピークが消失したことより反応の終点を確認した。反応液にテトラヒドロフラン（ＴＨＦ）（５０ｇ）、トルエン（１０ｇ）及び水（５０ｇ）を加え、有機層を分離した。有機層を１０％の食塩水で洗浄した後、溶媒を減圧留去して、濃縮物にメタノールを加えて、化合物（ｂ－３－１）を得た。
ナスフラスコに化合物（ｂ－３－１）（２．００ｇ、８．２２ｍｍｏｌ）及びジクロロメタン（１２．７ｇ）を加え、混合物を撹拌し、窒素雰囲気下で－５℃に冷却した。次に、三臭化ホウ素１７％ジクロロメタン溶液（２２．６９ｇ、１５．４ｍｍｏｌ）を滴下し、滴下終了後は室温下で２時間反応させた。反応溶液に氷水を加えた後、酢酸エチルを加え、有機層を抽出した。溶媒を減圧留去して、化合物（ｂ－３－２）を得た。
４つ口フラスコに化合物（ｂ－３－２）（１．６８ｇ、７．８４ｍｍｏｌ）、２４％水酸化ナトリウム水溶液（５．２０ｇ、３１．４ｍｍｏｌ）及び純水（４．３２ｇ）を加えて、室温下において、撹拌下に、３７％ホルムアルデヒド水溶液（６．３５ｇ、７８．４ｍｍｏｌ）を滴下して反応させた。反応溶液を３０～４０℃に昇温して撹拌した後、反応溶液の一部を取り出してＬＣ／ＭＳを測定し、原料のピークが消失したことより反応の終点を確認した。反応終了後、得られた反応混合物を酢酸で中和し、この後、２時間撹拌して、析出した結晶を濾過した。溶媒を減圧留去して化合物（ｂ－３）を得た。 <Synthesis example (b-3)>
Compound (b-3) was synthesized according to the route shown below.

4,4'-dimethoxydiphenylamine (3.00 g, 13.1 mmol), potassium carbonate (5.43 g, 39.3 mmol) and N,N-dimethylformamide (DMF) (18.6 g) were added to a recovery flask, The mixture was stirred at room temperature. Next, iodomethane (7.43 g, 52.3 mmol) was added, and the mixture was heated to 40-50° C. and stirred. After that, a portion of the reaction solution was taken out and measured by LC/MS. The end point of the reaction was confirmed by the disappearance of the peak of the raw material. Tetrahydrofuran (THF) (50 g), toluene (10 g) and water (50 g) were added to the reaction solution, and the organic layer was separated. After washing with a saline solution, the solvent was distilled off under reduced pressure, and methanol was added to the concentrate to obtain compound (b-3-1).
Compound (b-3-1) (2.00 g, 8.22 mmol) and dichloromethane (12.7 g) were added to a recovery flask, and the mixture was stirred and cooled to −5° C. under a nitrogen atmosphere. A 17% dichloromethane solution of boron bromide (22.69 g, 15.4 mmol) was added dropwise, and after the completion of the dropwise addition, the mixture was allowed to react at room temperature for 2 hours. Ice water was added to the reaction solution, and then ethyl acetate was added, and the organic layer was The solvent was removed under reduced pressure to obtain compound (b-3-2).
Compound (b-3-2) (1.68 g, 7.84 mmol), a 24% aqueous sodium hydroxide solution (5.20 g, 31.4 mmol), and pure water (4.32 g) were placed in a four-neck flask, At room temperature, 37% aqueous formaldehyde solution (6.35 g, 78.4 mmol) was added dropwise with stirring to cause a reaction. The reaction solution was heated to 30 to 40° C. and stirred, and then a portion of the reaction solution was The end of the reaction was confirmed by the disappearance of the peak of the raw material. After the reaction was completed, the reaction mixture was neutralized with acetic acid, and then stirred for 2 hours. The precipitated crystals were filtered, and the solvent was distilled off under reduced pressure to obtain compound (b-3).

ナスフラスコに、５－（３－ピリジニル）－１，３－ベンゼンジカルボン酸（ＣＡＳ Ｎｏ．１２６２９６２－０６－０）（４．３８ｇ、１８．０ｍｍｏｌ）、チラミン（５．１７ｇ、３７．７ｍｍｏｌ）及びＮ，Ｎ－ジメチルホルムアミド（ＤＭＦ）（１００ｇ）を加えて、混合物を室温で撹拌した。次に、Ｎ－エチルモルホリン（４．３４ｇ、３７．７ｍｍｏｌ）、４－（４，６－ジメトキシ－１，３，５－トリアジン－２－イル）－４－メチルモルホリニウムクロリド（ＤＭＴ－ＭＭ）（１０．４３ｇ、３７．７ｍｍｏｌ）を加えて、一晩室温で撹拌した。反応溶液に水（６００ｇ）を加えて、固体を析出させ、得られた固体をメタノールで洗浄した。次に、溶媒を減圧留去して化合物（ｂ－４－１）を得た。
次に、Ｓｃｈｅｍｅ２において、化合物（ｂ－３－２）を化合物（ｂ－４－１）に変更した以外は同様の手順で合成し、化合物（ｂ－４）を得た。 <Synthesis example (b-4)>
Compound (b-4) was synthesized according to the route shown below.

In a recovery flask, 5-(3-pyridinyl)-1,3-benzenedicarboxylic acid (CAS No. 1262962-06-0) (4.38 g, 18.0 mmol), tyramine (5.17 g, 37.7 mmol), and N,N-Dimethylformamide (DMF) (100 g) was added and the mixture was stirred at room temperature. Next, N-ethylmorpholine (4.34 g, 37.7 mmol), 4-(4,6-dimethoxy-1-methyl-2-propanediol (DMF) (100 g) were added and the mixture was stirred at room temperature. ,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) (10.43 g, 37.7 mmol) was added and stirred at room temperature overnight. ) was added to precipitate a solid, and the resulting solid was washed with methanol. Next, the solvent was distilled off under reduced pressure to obtain compound (b-4-1).
Next, compound (b-4) was obtained by synthesizing in the same manner as in Scheme 2, except that compound (b-3-2) was changed to compound (b-4-1).

<Synthesis example (b-5)>
In Scheme 2, the compound (b-3-2) was replaced with 4,4'-(2-pyridinylmethylene)bisphenol (CAS No. 603-41-8), but the same procedure was followed to synthesize the compound ( b-5) was obtained.

<Synthesis example (b-6)>
In Scheme 2, the same procedure was followed except that compound (b-3-2) was changed to 4-[[4-(2-pyridinyl)-1-piperazinyl]methyl]phenol (CAS No. 414887-31-3). Compound (b-6) was obtained by synthesis.

Ｍａｍｅｒｉ，Ｓａｍｉｒ ｅｔ ａｌ．，Ｅｕｒｏｐｅａｎ Ｊｏｕｒｎａｌ ｏｆ Ｉｎｏｒｇａｎｉｃ Ｃｈｅｍｉｓｔｒｙ（２０１４）２６：４３２６～４３３４に記載されているのと同様の手順に従って２，６－ビス（ヒドロキシメチル）－４－アミノフェノールを調製した。
４つ口フラスコに化合物（ｂ－７－１）（ＣＡＳ Ｎｏ．２２１００－８８－５）（５．００ｇ、１８．９ｍｍｏｌ）及びＮ，Ｎ－ジメチルホルムアミド（ＤＭＦ）（４５ｇ）を加えて、混合物を室温下で撹拌した。次に、２，６－ビス（ヒドロキシメチル）－４－アミノフェノール（６．４０ｇ、３７．８ｍｍｏｌ）を加え、室温で撹拌した。ジオキサンを加えて固体を析出させ、得られた固体から溶媒を減圧留去して化合物（ｂ－７）を得た。 <Synthesis example (b-7)>
Compound (b-7) was synthesized according to the route shown below.

2,6-Bis(hydroxymethyl)-4-aminophenol was prepared according to a similar procedure as described in Mameri, Samir et al., European Journal of Inorganic Chemistry (2014) 26:4326-4334.
Compound (b-7-1) (CAS No. 22100-88-5) (5.00 g, 18.9 mmol) and N,N-dimethylformamide (DMF) (45 g) were added to a four-neck flask, and the mixture was The mixture was stirred at room temperature. Next, 2,6-bis(hydroxymethyl)-4-aminophenol (6.40 g, 37.8 mmol) was added, and the mixture was stirred at room temperature. Dioxane was added to precipitate a solid. The solvent was removed from the resulting solid by distillation under reduced pressure to obtain compound (b-7).

<Synthesis example (b-8)>
Compound (b-8) was synthesized in the same manner as in Scheme 4, except that compound (b-7-1) was changed to 3,5-diisocyanatopyridine (CAS No. 1620557-50-7). Got it.

４つ口フラスコに４－ヒドロキシフェニルボロン酸ピナコール（７．１０ｇ、３２．３ｍｍｏｌ）、４，６－ジブロモピリミジン（２．５７ｇ、１０．８ｍｍｏｌ）、炭酸カリウム（４．４５ｇ、３２．３ｍｍｏｌ）、水（８２ｇ）及び１，４－ジオキサン（２５０ｍＬ）を加えて、混合物を撹拌し、反応系内を窒素置換した。次に、テトラキス（トリフェニルホスフィン）パラジウム（０．６４ｇ）を加えて、１００℃で一晩加熱撹拌を行った。反応溶液にクロロホルムを加え、クロロホルム層を取り出した後、溶媒を減圧留去した。得られた濃縮物にメタノール及び水を加えて、化合物（ｂ－９－１）を得た。
４つ口フラスコに（ｂ－９－１）（１．００ｇ、３．７８ｍｍｏｌ）、２４％水酸化ナトリウム水溶液（２．５１ｇ、１５．１ｍｍｏｌ）及び純水（２．１６ｇ）を加えて、室温下において、撹拌下に、３７％ホルムアルデヒド水溶液（３．０６ｇ、３７．８ｍｍｏｌ）を滴下して反応させた。反応溶液を３０～４０℃に昇温して撹拌した後、反応溶液の一部を取り出してＬＣ／ＭＳを測定し、原料のピークが消失したことより反応の終点を確認した。反応終了後、得られた反応混合物を酢酸で中和し、この後、２時間撹拌して、析出した結晶を濾過した。溶媒を減圧留去して化合物（ｂ－９）を得た。 <Synthesis example (b-9)>
Compound (b-9) was synthesized according to the route shown below.

In a four-neck flask, 4-hydroxyphenyl pinacol boronic acid (7.10 g, 32.3 mmol), 4,6-dibromopyrimidine (2.57 g, 10.8 mmol), potassium carbonate (4.45 g, 32.3 mmol), Water (82 g) and 1,4-dioxane (250 mL) were added, the mixture was stirred, and the reaction system was purged with nitrogen. Next, tetrakis(triphenylphosphine)palladium (0.64 g) was added, and 100 The mixture was heated and stirred at 0.degree. C. overnight. Chloroform was added to the reaction solution, and the chloroform layer was taken out, and the solvent was then distilled off under reduced pressure. Methanol and water were added to the resulting concentrate to obtain the compound (b-9- 1) was obtained.
Into a four-neck flask, (b-9-1) (1.00 g, 3.78 mmol), a 24% aqueous sodium hydroxide solution (2.51 g, 15.1 mmol), and pure water (2.16 g) were added, and the mixture was heated at room temperature. A 37% aqueous formaldehyde solution (3.06 g, 37.8 mmol) was added dropwise under stirring at a temperature of 30 to 40° C. to react with the mixture. The reaction solution was heated to 30 to 40° C. and stirred, and then a portion of the reaction solution was poured into The reaction mixture was taken out and analyzed by LC/MS, and the end point of the reaction was confirmed by the disappearance of the peak of the raw material. After the reaction was completed, the reaction mixture was neutralized with acetic acid, and then stirred for 2 hours to precipitate The precipitated crystals were filtered, and the solvent was removed under reduced pressure to obtain compound (b-9).

[Synthesis of Polymer (A)]
<Synthesis Example 1>
CA-2 (2.25 g, 8.99 mmol), DA-6 (2.97 g, 8.99 mmol), DA-7 (3.43 g, 9.01 mmol), and NMP (34.6 g) were added to a four-neck flask equipped with a stirrer and a nitrogen inlet tube, and were dissolved therein, followed by reaction for 4 hours at 60° C. Thereafter, CA-3 (1.75 g, 8.92 mmol) and NMP (6.99 g) were added thereto, and the mixture was reacted for 4 hours at 40° C. to obtain a polyamic acid solution.
The polyamic acid solution (40 g) was diluted to 6.5% by mass by adding NMP, and then acetic anhydride (7.06 g) and pyridine (2.19 g) were added as imidization catalysts and reacted at 80° C. for 4 hours. The reaction solution was poured into methanol (463 g), and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100° C. to obtain a polyimide powder. The imidization rate of this polyimide was 74%, the number average molecular weight was 12,500, and the weight average molecular weight was 38,500.
NMP (18.0 g) was added to the obtained polyimide powder (2.0 g), and M-1 was added thereto so that the amount was 1% by mass based on the polyimide solid content, and the mixture was dissolved by stirring at 70° C. for 12 hours to obtain a solution of polyimide (PI-V-1) having a solid content concentration of 10%.

<Synthesis Example 2>
In a four-neck flask equipped with a stirrer and a nitrogen inlet tube, CA-2 (1.20 g, 4.80 mmol), DA-8 (1.46 g, 9.59 mmol), DA-9 (1.74 g, 7.18 mmol), and DA-7 (2.74 g, 7.20 mmol) and NMP (28.58 g) were added and dissolved, and reacted at 60° C. for 2 hours. Thereafter, CA-5 (1.05 g, 4.81 mmol) and NMP (4.19 g) were added, and reacted at room temperature for 4 hours, and further CA-3 (2.78 g, 14.18 mmol) and NMP (11.1 g) were added, and reacted at room temperature for 4 hours to obtain a polyamic acid solution.
The polyamic acid solution (40 g) was diluted to 6.5% by mass by adding NMP, and then acetic anhydride (8.90 g) and pyridine (2.76 g) were added as imidization catalysts and reacted at 80° C. for 4 hours. The reaction solution was poured into methanol (472 g), and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100° C. to obtain a polyimide powder. The imidization rate of this polyimide was 74%, the number average molecular weight was 13,000, and the weight average molecular weight was 39,000.
NMP was added to the obtained polyimide powder so that the solid content concentration was 10 mass %, and M-1 was added so that the concentration was 1 mass % based on the polyimide solid content, and the mixture was dissolved by stirring at 70° C. for 12 hours to obtain a solution of polyimide (PI-V-2).

<Synthesis Example 3>
5.86 g (24.0 mmol) of DA-2, 5.46 g (16.0 mmol) of DA-10, 1.73 g (16.0 mmol) of DA-4, 7.69 g (24.0 mmol) of DA-1, and 194 g of NMP were added to a four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring while feeding nitrogen. 17.1 g (76.4 mmol) of CA-1 was added while stirring this diamine solution, and NMP was further added so that the solid content concentration became 12% by mass, and the mixture was stirred at 40° C. for 24 hours to obtain a polyamic acid solution (viscosity: 549 mPa·s). The molecular weight of the polyamic acid was a number average molecular weight of 12,400 and a weight average molecular weight of 33,000.
The polyamic acid solution (225 g) was diluted to 9.0% by mass by adding NMP, and then acetic anhydride (17.1 g) and pyridine (3.54 g) were added as imidization catalysts and reacted at 55° C. for 3 hours. The reaction solution was poured into methanol (1111 g), and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried at 60° C. for 12 hours to obtain a polyimide powder. The imidization rate of the polyimide powder was 66%, the number average molecular weight was 11,000, and the weight average molecular weight was 28,000.
NMP was added to the obtained polyimide powder so that the solid content concentration became 15% by mass, and the mixture was dissolved by stirring at 70° C. for 24 hours to obtain a solution of polyimide (PI-I-3).

<Synthesis Example 4>
5.73 g (20.0 mmol) of DA-5 was weighed out into a 5 L four-neck flask equipped with a stirrer and a nitrogen inlet tube, 115 g of NMP was added, and the mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution under water cooling, 2.94 g (15.0 mmol) of CA-3 was added, 19.1 g of NMP was added, and the mixture was stirred at 23°C under a nitrogen atmosphere for 1 hour. Thereafter, 11.9 g (40.0 mmol) of DA-3 and 6.01 g (40.0 mmol) of DA-11 were weighed out, 172 g of NMP was added, and the mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution under water cooling, 15.9 g (81.0 mmol) of CA-3 was added, NMP was added so that the solid content concentration became 15 mass %, s-1 was added so that the solid content was 1 mass % based on the polyamic acid solid content, and the mixture was stirred at 23° C. for 6 hours under a nitrogen atmosphere to obtain a solution of polyamic acid (PAA-I-4). The molecular weight of the polyamic acid was a number average molecular weight of 12,000 and a weight average molecular weight of 30,000.

<Synthesis Example 5>
A 500 mL four-neck flask equipped with a stirrer was placed in a nitrogen atmosphere, and 2.80 g (25.9 mmol) of DA-4, 1.54 g (6.47 mmol) of DA12, 111 g of NMP, and 6.18 g (78.1 mmol) of pyridine as a base were added and stirred to dissolve. Next, 9.89 g (30.4 mmol) of CE-1 was added while stirring this diamine solution, and reacted at 15 ° C. overnight. After stirring overnight, 0.38 g (4.21 mmol) of E-1 was added and reacted at 15 ° C. for 4 hours. The obtained polyamic acid ester solution was poured into 1230 g of water while stirring, and the precipitated white precipitate was filtered, and then washed five times with 1230 g of isopropyl alcohol (IPA), and dried to obtain 10.2 g of white polyamic acid ester resin powder. The yield was 83.0%. The molecular weight of this polyamic acid ester was 20,786 in number average molecular weight and 40,973 in weight average molecular weight.
GBL was added to the obtained polyamic acid ester so that the solid content concentration became 10% by mass, and the mixture was stirred at room temperature for 24 hours to dissolve, thereby obtaining a solution of polyamic acid ester (PAE-I-5).

<Synthesis Example 6>
In a four-neck flask equipped with a stirrer and a nitrogen inlet tube, 0.46 g (3.00 mmol) of DA-8, 3.00 g (15.0 mmol) of DA-13, 2.56 g (12.0 mmol) of DA-14, 11.0 g of NMP, and 8.10 g of GBL were added, and dissolved by stirring while feeding nitrogen. While stirring this diamine solution, 4.76 g (24.0 mmol) of CA-6 was added, 10.9 g of GBL was added, and the mixture was stirred at room temperature for 2 hours. Next, 10.8 g of GBL was added and stirred, after which 1.31 g (6.01 mmol) of CA-5 was added, 14.3 g of GBL was added, and the mixture was stirred at room temperature for 24 hours. The viscosity of the obtained polyamic acid solution at 25°C was 2,041 mPa·s. The molecular weight of the polyamic acid was a number average molecular weight of 14,200 and a weight average molecular weight of 30,110. Thereafter, s-2 was added to the polyamic acid so that the amount was 1 mass % relative to the solid content of the polyamic acid, and NMP and GBL were added so that the mixing ratio of NMP and GBL became NMP:GBL=20:80 by mass and the solid content concentration became 15 mass %, thereby obtaining a solution of polyamic acid (PAA-I-6).

<Synthesis Examples 7 to 11, 14 to 19>
The diamines, tetracarboxylic acid derivatives, and organic solvents shown in Table 1 below were used, and the same procedures as those in the above synthesis examples were carried out to obtain solutions of polyimides (PI-V-8) to (PI-V-9), (PI-I-11), and (PI-V-19), polyamic acids (PAA-I-7), (PAA-I-10), (PAA-V-14) to (PAA-V-16), and (PAA-I-17) to (PAA-I-18) shown in Table 1 below. In Table 1, the numbers in parentheses represent the blending ratio (molar parts) of each compound relative to 100 molar parts of the total amount of tetracarboxylic acid derivatives used in the synthesis for the tetracarboxylic acid component, and the blending ratio (molar parts) of each compound relative to 100 molar parts of the total amount of diamines used in the synthesis for the diamine component. The terminal modifier represents the blending ratio (molar parts) relative to 100 molar parts of the total amount of diamines used in the synthesis. The organic solvents are expressed as the blending ratio (parts by mass) of each organic solvent relative to 100 parts by mass of the total amount of the organic solvents used in the synthesis.

[Synthesis of other polymers]
<Synthesis Example 12>
According to the method described in paragraph [0091] of JP 2018-054761 A, a reactive polyorganosiloxane polymer was obtained using 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECETS). Next, according to the method described in paragraph [0093] of JP 2018-054761 A, a polyorganosiloxane polymer represented by the following formula (P-S1) was obtained. The numerical values indicate the proportion of each compound used relative to the total of each silane compound used in the synthesis.

<Synthesis Example 13>
According to the method described in paragraph [0091] of JP 2018-54761 A, a reactive polyorganosiloxane polymer was obtained using 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (ECETS). Next, according to the method described in paragraph [0093] of JP 2018-54761 A, a polyorganosiloxane polymer represented by the following formula (P-S2) was obtained. The numerical values indicate the proportion of each compound used relative to the total of each silane compound used in the synthesis.

Example 1
[Preparation of liquid crystal alignment agent]
Using the solution of polyimide (PI-V-1) obtained in Synthesis Example 1 and the solution of polyimide (PI-V-2) obtained in Synthesis Example 2, dilute with NMP and BCS, and further add compound (b-1) so that it is 10 parts by mass relative to 100 parts by mass of all polymers and stir at room temperature. Next, by filtering the obtained solution with a filter having a pore size of 0.5 μm, the component ratio of the polymer is (PI-V-1): (PI-V-2) = 30: 70 (solid content equivalent mass ratio), the solvent composition ratio is NMP: BCS = 60: 40 (mass ratio), the polymer solid content concentration is 4.5%, and the compound (b-1) is 10 parts by mass relative to the total 100 parts by mass of the polymer components to obtain a liquid crystal alignment agent (V1) (Table 2 below). It was confirmed that this liquid crystal alignment agent was a uniform solution without any abnormalities such as turbidity or precipitation.

<Examples 2 to 50, Comparative Examples 1 to 5>
Except for using the polymers and additives in Tables 2 to 6 below, the same procedure as in Example 1 was carried out to obtain liquid crystal alignment agents (V2) to (V11), (I12-P) to (I29-P), (I30-U) to (I37-U), (V38) to (V43), (I44-P) to (I47-P), (V48-P) to (V49-P), (I50-U), (R-V1) to (R-V2), (R-I3-P), (R-I4-U), and (R-V5). In Table 2, the numbers in parentheses represent the blending ratio (parts by mass) of each polymer component or additive relative to the total of 100 parts by mass of the polymer components used in the preparation of the liquid crystal alignment agent, respectively, for the polymer and additive. For the organic solvent, the blending ratio (parts by mass) of each organic solvent relative to the total of 100 parts by mass of the organic solvent used in the preparation of the liquid crystal alignment agent is represented.

[Preparation and Evaluation of Liquid Crystal Display Element]
1-1. Preparation of vertical alignment type liquid crystal display element Two glass substrates with ITO electrodes of 40 mm x 30 mm (length: 40 mm, width: 30 mm, thickness: 1.1 mm) were prepared and washed with pure water and isopropyl alcohol. Next, liquid crystal alignment agents (V1) to (V11), (V38) to (V43), (R-V1) to (R-V2), and (R-V5) filtered with a filter having a pore size of 1.0 μm were spin-coated on each ITO surface, and the substrates were heated at 70° C. for 90 seconds on a hot plate and at 230° C. for 30 minutes in a heat circulation type clean oven to obtain an ITO substrate with a film having a film thickness of 100 nm.
Next, the periphery was coated with a sealant (Mitsui Chemicals, Inc., XN-1500T). Next, the other substrate was attached to the previous substrate with the surface on which the liquid crystal alignment film was formed facing inward, and the sealant was cured to prepare an empty cell. Liquid crystal MLC-3023 (Merck, Inc.) was injected by a reduced pressure injection method into the empty cells using the liquid crystal alignment agents (V1) to (V2), (V5) to (V11), (V38) to (V43), and (R-V1), to prepare a liquid crystal cell.
Thereafter, a direct current voltage of 15 V was applied to the obtained liquid crystal cell, and in the state where all pixel areas were driven, 10 J/ ^cm2 of ultraviolet light that had passed through a bandpass filter with a wavelength of 365 nm was irradiated using an ultraviolet irradiation device using a high-pressure mercury lamp as a light source, to obtain a liquid crystal display element for evaluation. The amount of ultraviolet light irradiation was measured using a UV-35 receiver connected to a UV-M03A manufactured by ORC Corporation.
Liquid crystal MLC-6608 (Merck) was injected into the empty cells using the liquid crystal alignment agents (V3) to (V4), (R-V2) and (R-V5) by the reduced pressure injection method to obtain liquid crystal display elements for evaluation. When the obtained liquid crystal display elements were observed with a polarizing microscope, it was confirmed that the liquid crystal was uniformly aligned in all cases.

1-2. Evaluation of Liquid Crystal Display Element (i) Evaluation of Accumulated Charge A square wave of 30 Hz, 7.8 V _p-p superimposed with 2 V DC was applied to the liquid crystal display element prepared in 1-1 above for 72 hours at 23°C, and the voltage remaining in the liquid crystal cell one hour after the DC voltage was turned off (residual DC voltage) was determined by the flicker elimination method. A value of 50 mV or less was judged as "excellent," a value of more than 50 mV and less than 150 mV was judged as "good," and a value of more than 150 mV was judged as "poor." The evaluation results are shown in Tables 7 to 9.
(ii) Voltage Retention Ratio Evaluation The liquid crystal display element prepared in 1-1 above was left in an oven at 80°C under irradiation of an LED lamp for 200 hours, and then left at room temperature to naturally cool to room temperature. After that, a voltage of 1V was applied at 60°C for 60 microseconds with a span of 1667 milliseconds, and the voltage retention ratio was measured 1,000 milliseconds after the application was removed. A measuring device manufactured by Toyo Corporation was used.
(iii) Evaluation of scratch resistance A liquid crystal alignment film was prepared on a pair of glass substrates (length: 40 mm, width: 30 mm, thickness: 1.1 mm) in the same manner as in 1-1 above. A scratch test was performed on each liquid crystal alignment film surface using UMT-2 (manufactured by Bruker AXS).
The FVL was selected as the sensor for UMT-2, and a 1.6 mm sapphire ball was attached to the tip of the scratched part.
The tip of the scratched area was brought into contact with the liquid crystal alignment film surface under a load of 40 mN, and a scratch was made over an area of 0.5 mm horizontal and 2.0 mm vertical. The tip of the scratched area was moved back and forth horizontally at a moving speed of 5.0 mm/sec. The scratched area was moved vertically by moving the substrate with the liquid crystal alignment film vertically at a speed of 20 μm/sec.
After the scratch test, liquid crystal (MLC-3019) was dropped onto the surface of the liquid crystal alignment film that had been subjected to the scratch test. Another substrate with a liquid crystal alignment film and 4 μm spacers dispersed thereon was placed on top of the substrate so that the liquid crystal alignment film surfaces faced each other, and the dropped liquid crystal was sandwiched between them.
The scratch test was performed on the area under a polarizing microscope (Eclipse E600WPOL) (Nikon Corporation) with the polarization axes of the upper and lower polarizing plates set at 90° (crossed Nicols), and the area was observed to see whether light was transmitted. The scratch test results are shown in Tables 7 to 9, with a condition in which no bright spots or light leakage were observed at all being "good" and a condition in which the entire scratched area was light-free being "poor."

2-1. Preparation of FFS-type liquid crystal display element by photo-alignment First, a substrate with electrodes was prepared. The substrate was a glass substrate with a size of 30 mm x 50 mm and a thickness of 0.7 mm. An ITO electrode with a solid pattern was formed on the substrate as the first layer, which constitutes the counter electrode. A SiN (silicon nitride) film formed by a CVD method was formed as the second layer on the first layer of the counter electrode. The thickness of the second layer of the SiN film was 500 nm, and it functions as an interlayer insulating film. A comb-shaped pixel electrode formed by patterning an ITO film as the third layer was arranged on the second layer of the SiN film, forming two pixels, a first pixel and a second pixel. The size of each pixel was 10 mm long and about 5 mm wide. At this time, the first layer of the counter electrode and the third layer of the pixel electrode were electrically insulated by the action of the second layer of the SiN film.

The pixel electrodes in the third layer have a comb-like shape consisting of multiple V-shaped electrode elements arranged with the central portion bent at an internal angle of 160°. The width of each electrode element in the short direction is 3 μm, and the distance between the electrode elements is 6 μm. Because the pixel electrodes forming each pixel are arranged with multiple V-shaped electrode elements bent at the central portion, the shape of each pixel is not rectangular, but has a bold V-shaped shape that is bent at the central portion like the electrode elements. Each pixel is divided into upper and lower parts by the central bend, and has a first region above the bent part and a second region below the bent part.

Next, the liquid crystal alignment agents (I12-P) to (I29-P), (I44-P) to (I47-P) and (R-I3-P) were filtered through a filter having a pore size of 1.0 μm, and then applied by spin coating to the above-mentioned electrode-attached substrate and a glass substrate having a columnar spacer with a height of 4 μm and an ITO film formed on the back surface.
The coating films obtained from the liquid crystal alignment agents (I12-P) to (I29-P) and (R-I3-P) were dried on a hot plate at 80° C. for 5 minutes, and then baked in a hot air circulation oven at 230° C. for 20 minutes to obtain a polyimide film with a thickness of 100 nm. Thereafter, the coating surface was irradiated with 500 mJ/cm ² of linearly polarized ultraviolet light with a wavelength of 254 nm and an extinction ratio of 26:1 through a polarizing plate, and then baked for 30 minutes in a hot air circulation oven at 230° C. to obtain a substrate with a liquid crystal alignment film with a thickness of 100 nm.
The coating films obtained from the liquid crystal alignment agents (I44-P) to (I47-P) were dried on a hot plate at 80°C for 5 minutes, and then the coating surface was irradiated with 500 mJ/ ^cm2 of linearly polarized ultraviolet light having a wavelength of 254 nm and an extinction ratio of 26:1 through a polarizing plate, and then baked in a hot air circulating oven at 230°C for 30 minutes to obtain a substrate with a liquid crystal alignment film having a thickness of 100 nm.
Next, a sealant was printed on one of the pair of glass substrates with liquid crystal alignment film, and the other substrate was attached so that the liquid crystal alignment film faces each other, and the sealant was cured to prepare an empty cell. Liquid crystal MLC-3019 (Merck) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS drive liquid crystal display element. The obtained liquid crystal cell was then heated at 120°C for 1 hour and left overnight, after which the afterimage characteristics were evaluated. When the obtained liquid crystal display elements were observed with a polarizing microscope, it was confirmed that the liquid crystal was uniformly oriented in all cases.

2-2. Evaluation of Liquid Crystal Display Element (i) Evaluation of Accumulated Charge The liquid crystal cell prepared in 2-1 above was used and placed between two polarizing plates arranged so that the polarization axes are perpendicular to each other. In a state where the pixel electrode and the counter electrode were short-circuited to have the same potential, an LED backlight was irradiated from below the two polarizing plates, and the angle of the liquid crystal cell was adjusted so that the brightness of the LED backlight transmitted light measured on the two polarizing plates was minimized. Next, while applying a square wave with a frequency of 30 Hz to this liquid crystal cell, the VT characteristic (voltage-transmittance characteristic) was measured at a temperature of 23°C, and the AC voltage at which the relative transmittance was 23% was calculated. Next, an AC voltage at which the relative transmittance was 23% at a temperature of 23°C and a square wave with a frequency of 30 Hz were applied for 5 minutes, and then a DC voltage of +1.0 V was superimposed and driven for 30 minutes. Thereafter, the DC voltage was turned off, and again an AC voltage at which the relative transmittance was 23% and only a square wave with a frequency of 30 Hz was applied for 30 minutes. The evaluation was performed by defining a case where the relative transmittance after 30 minutes of DC voltage superposition was reduced to less than 27% as "excellent," a case where it was reduced to 27% or more but less than 29% as "good," and a case where the relative transmittance was 29% or more as "poor."
(ii) Voltage holding ratio evaluation Two 40 mm × 30 mm glass substrates with ITO electrodes (length: 40 mm, width: 30 mm, thickness: 1.1 mm) were prepared, and a liquid crystal alignment film with a thickness of 100 nm was formed on the ITO surface in the same manner as in 2-1 above. Bead spacers with a diameter of 4 μm (manufactured by JGC Catalysts and Chemicals, Shinshikyu, SW-D1) were applied to the liquid crystal alignment film surface of one of the substrates.
Next, the periphery was coated with a sealant (XN-1500T manufactured by Mitsui Chemicals). Next, the other substrate was laminated with the surface on which the liquid crystal alignment film was formed facing inward, and the sealant was cured to prepare an empty cell. Liquid crystal MLC-3019 (product name manufactured by Merck & Co.) was injected into this empty cell by a reduced pressure injection method to prepare a liquid crystal display element. Next, this liquid crystal display element was left to stand for 200 hours in an oven at 80° C. under irradiation by an LED lamp, and then left to stand at room temperature and naturally cooled to room temperature. Thereafter, evaluation was performed in the same manner as in 1-2 (ii).
(iii) Evaluation of Scratch Resistance The same procedure as in (iii) of 1-2 above was followed, except that the same liquid crystal alignment film as in 2-1 above was used and the liquid crystal was changed to MLC-3019.

3-1. Preparation of FFS-type liquid crystal display element by rubbing alignment First, the liquid crystal alignment agents (I30-U) to (I37-U), (I50-U), and (R-I4-U) filtered with a filter having a pore size of 1.0 μm were applied to each surface of a pair of glass substrates similar to those in 2-1 above using an inkjet coating device (HIS-200, manufactured by Hitachi Plant Technologies, Ltd.). The coating was performed under the conditions of a coating area of 70 × 70 mm, a nozzle pitch of 0.423 mm, a scan pitch of 0.5 mm, a coating speed of 40 mm/sec, and a delay of 60 seconds from coating to drying. Next, the film was dried on a hot plate at 80 ° C. for 5 minutes, and then baked in a hot air circulation oven at 230 ° C. for 20 minutes to obtain a polyimide film with a thickness of 100 nm. This polyimide film was rubbed with a rayon cloth (roller diameter: 120 mm, roller rotation speed: 500 rpm, moving speed: 30 mm/sec, indentation length: 0.3 mm, rubbing direction: inclined at 10° to the third layer IZO comb electrode), and then ultrasonically irradiated in pure water for 1 minute to wash and remove water droplets. Then, it was dried at 80° C. for 15 minutes to obtain a substrate with a liquid crystal alignment film. These two substrates with a liquid crystal alignment film were combined into one set, and a sealant was printed on the substrate with a liquid crystal injection port remaining, and another substrate was attached so that the liquid crystal alignment film surfaces faced each other and the rubbing directions were antiparallel. Then, the sealant was cured to prepare an empty cell with a cell gap of 4 μm. Liquid crystal MLC-7026-100 (manufactured by Merck) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS type liquid crystal display element. Thereafter, the obtained liquid crystal display element was heated at 120° C. for 1 hour, and then left overnight at 23° C. before being used for evaluation of afterimages. When the obtained liquid crystal display element was observed with a polarizing microscope, it was confirmed that the liquid crystal was uniformly aligned in each case.

3-2. Evaluation of Liquid Crystal Display Element (i) Evaluation of Accumulated Charge Using the liquid crystal display element prepared in the above 3-1, evaluation was carried out in the same manner as in the above 2-2(i), except that the liquid crystal was changed to MLC-7026-100.
(ii) Evaluation of Voltage Holding Ratio Evaluation was performed in the same manner as in (ii) of 2-2 above, except that the same liquid crystal alignment film as in 3-1 above was used and the liquid crystal was changed to MLC-7026-100.
(iii) Evaluation of Scratch Resistance Using the same liquid crystal alignment film as in 3-1 above, evaluation was carried out in the same manner as in (iii) of 2-2 above, except that the liquid crystal was MLC-7026-100.

4-1. Fabrication of VA-type liquid crystal display element by photo-alignment Two glass substrates similar to those in 1-1 above were prepared, and liquid crystal alignment agent (V48-P) or (V49-P) was spin-coated on each substrate, and the substrates were heat-treated at 80°C for 90 seconds on a hot plate and at 200°C for 40 minutes in a heat circulation type clean oven to obtain an ITO substrate with a liquid crystal alignment film having a thickness of 100 nm.
The substrate was then exposed to linearly polarized UV light at an incidence angle of 40° relative to the normal of the substrate surface. The applied exposure dose was 20 mJ/ ^cm2 . After exposure, a cell having two substrates was assembled so that the exposed alignment layer faced the inside of the cell, and the substrates were adjusted so that the alignment directions were parallel to each other. Next, liquid crystal MLC-7067 (Merck) was injected. After that, the device was annealed at about 90°C for 10 minutes, cooled to room temperature, and then used for evaluation of image retention. When the obtained liquid crystal display device was observed with a polarizing microscope, it was confirmed that the liquid crystal was uniformly aligned in all cases.

4-2. Evaluation of Liquid Crystal Display Element (i) Evaluation of Accumulated Charge Using the liquid crystal display element prepared in the above 4-1, evaluation was carried out in the same manner as in the above 1-2 (i). The evaluation results are shown in Tables 7 to 9.
(ii) Evaluation of Voltage Holding Ratio Evaluation was performed in the same manner as in (ii) of 1-2 above, except that the same liquid crystal alignment film as in 4-1 above was used and the liquid crystal was changed to MLC-7067. The evaluation results are shown in Tables 7 to 9.
(iii) Evaluation of scratch resistance Evaluation was performed in the same manner as in (iii) of 1-2 above, except that the same liquid crystal alignment film as in 4-1 above was used and the liquid crystal was changed to MLC-7067. The evaluation results are shown in Tables 7 to 9.

The liquid crystal aligning agent of the present invention is useful for forming a liquid crystal alignment film in various liquid crystal display elements such as a vertical alignment type and an FFS driving type.
In addition, the entire contents of the specification, claims and abstract of Japanese Patent Application No. 2019-044856 filed on March 12, 2019 are hereby incorporated by reference as the disclosure of the specification of the present invention.

Claims (18)

A liquid crystal aligning agent comprising the following components (A) and (B):
Component (A): A polymer (A) having at least one repeating unit selected from the group consisting of a repeating unit represented by the following formula (1) and a repeating unit represented by the following formula (2):
Component (B): A compound (B) having a molecular weight of 2000 or less, which has a partial structure represented by the following formula (b) in the molecule and is equipped with a basic site containing a nitrogen atom.

In formula (1), X ₁ is a tetravalent organic group selected from the group consisting of formulae (4a) to (4n), (5a) and (6a), and Y ₁ is a divalent organic group. _{R 1} is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and Z ₁₁ and Z ₁₂ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent, an alkenyl group having 2 to 10 carbon atoms which may have a substituent, an alkynyl group having 2 to 10 carbon atoms which may have a substituent, a tert-butoxycarbonyl group or a 9-fluorenylmethoxycarbonyl group.

* represents a bond, _R1 represents an alkanediyl group having 1 to 4 carbon atoms, and _m1 represents an integer of 1 or 2.

x and y are single bonds, ethers, carbonyls, esters, alkanediyl groups having 1 to 5 carbon atoms, 1,4-phenylene, sulfonyl or amide groups. Z ¹ to Z ⁶ each independently represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring. j and k are 0 or 1. m is an integer of 1 to 5. * represents a bond. A liquid crystal aligning agent comprising the following components (A) and (B):
Component (A): a polymer (A) having at least one repeating unit selected from the group consisting of a repeating unit represented by the following formula (1) and a repeating unit represented by the following formula (2):
Component (B): A compound (B) having a molecular weight of 2000 or less, which has a partial structure represented by the following formula (b) in the molecule and is equipped with a basic site containing a nitrogen atom,
The aforementioned compound, wherein the basic site has a structure selected from the group consisting of a secondary amine, a group in which one or two hydrogen atoms have been removed from a tertiary amine, and a nitrogen-containing heterocyclic group.

In formula (1), _X1 is a tetravalent organic group, _Y1 is a divalent organic group, _R1 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and _Z11 and _Z12 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent, an alkenyl group having 2 to 10 carbon atoms which may have a substituent, an alkynyl group having 2 to 10 carbon atoms which may have a substituent, a tert-butoxycarbonyl group, or a 9-fluorenylmethoxycarbonyl group.

* represents a bond, _R1 represents an alkanediyl group having 1 to 4 carbon atoms, and _m1 represents an integer of 1 or 2. The liquid crystal aligning agent according to claim 2 , wherein the X ₁ is a tetravalent organic group selected from the group consisting of the following formulas (4a) to (4n), the following formula (5a), and the following formula (6a).

x and y are single bonds, ethers, carbonyls, esters, alkanediyl groups having 1 to 5 carbon atoms, 1,4-phenylene, sulfonyl or amide groups. Z ¹ to Z ⁶ each independently represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring. j and k are 0 or 1. m is an integer of 1 to 5. * represents a bond. The polymer (A) contains one or more repeating units (repeating units (t)) selected from the group consisting of repeating units represented by the formula (1) and repeating units represented by the formula (2), in which X ₁ is a tetravalent organic group selected from the group consisting of the formulas (4a) to ₍ 4n), (5a), and (6a), and Y 1 is a divalent organic group, and the content of the repeating units (t) is 5 mol% or more in total with respect to the total repeating units of the polymer (A). The liquid crystal aligning agent according to claim 3. The liquid crystal aligning agent according to any one of claims ₁ to 4, wherein the polymer (A) contains one or more repeating units selected from the group consisting of repeating units represented by the formula ( ₁ ) and repeating units represented by the formula (2), in which X 1 is a tetravalent organic group and Y 1 is a divalent organic group derived from a diamine having at least one selected from the group consisting of a nitrogen-containing heterocycle, a diphenylamine structure, and a triphenylamine structure, and the content of the one or more repeating units is 5 mol% or more in total with respect to the total repeating units of the polymer (A). The liquid crystal aligning agent according to any one of claims 1 to 5, wherein the polymer (A ₎ contains one or more repeating units selected from the group consisting of repeating units represented by the formula (1) and repeating units represented by the formula (2), in which Y1 is a divalent organic group derived from a diamine having at least one selected from the group consisting of a nitrogen-containing heterocycle, a diphenylamine structure, and a triphenylamine structure, and the content of the one or more repeating units is 5 mol% or more in total with respect to all repeating units of the polymer (A). The polymer (A) contains _at least one repeating unit (a) selected from the group consisting of repeating units represented by the above formula (1) and repeating units represented by the above formula (2), in which X ₁ is a tetravalent organic group and Y 1 is a divalent organic group derived from a diamine represented by the following formulas (V1) to (V3), and the content of the repeating unit (a) is 1 mol% or more in total with respect to the total repeating units of the polymer (A). The liquid crystal aligning agent according to any one of claims 1 to 6.

X represents a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 ) _m- , -SO2-, -O-( _CH2 ) _m -O-, -O-C( _CH3 ) _2- , _-CO- ( _CH2 ) _m- , -NH-( _CH2 ) _m- , _-SO2- ( _CH2 ) _m- , -CONH-( _CH2 ) _m- , -CONH-( _CH2 ) _m -NHCO-, or -COO-( _CH2 ) _m -OCO-.
X ¹ and X ² each independently represent a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -COO-, -OCO-, or -((CH ₂ ) _a1 -A ₁ ) _m1 -. Among these, a1's each independently represent an integer of 1 to 15, A ₁ 's each independently represent an oxygen atom or -COO-, and m ₁ is 1 to 2. X ³ represents a single bond, -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or -OCO-. X ⁴ represents -CONH-, -NHCO-, -O-, -COO-, or -OCO-.
_G1 and _G2 each independently represent a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms. Any hydrogen atom on the cyclic group may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms, or a fluorine atom. k represents 0 or 1, m and n each independently represent an integer of 0 to 3, and the sum of m and n is 1 to 4.
^R1 represents 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. Any hydrogen forming ^R1 may be substituted with fluorine.
^R2 represents an alkyl group having 1 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms, and any hydrogen atom forming ^R2 may be substituted with a fluorine atom. ^R3 represents a structure having a steroid skeleton. The polymer (A) contains one or more repeating units (repeating units (a)) selected from the group consisting of repeating units represented by the above formula (1) and repeating units represented by the above formula (2), in which Y ₁ is a divalent organic group derived from a diamine represented by the following formulas (V1) to (V3), and the content of the repeating units (a) is 1 mol% or more in total with respect to all repeating units of the polymer (A). The liquid crystal aligning agent according to any one of claims 1 to 7.

X represents a single bond, -O-, -C( _CH3 ) _2- , -NH-, -CO-, -NHCO-, -COO-, -( _CH2 ) _m- , -SO2-, -O-( _CH2 ) _m -O-, -O-C( _CH3 ) _2- , _-CO- ( _CH2 ) _m- , -NH-( _CH2 ) _m- , _-SO2- ( _CH2 ) _m- , -CONH-( _CH2 ) _m- , -CONH-( _CH2 ) _m -NHCO-, or -COO-( _CH2 ) _m -OCO-.
X ¹ and X ² each independently represent a single bond, -(CH ₂ ) _a - (a is an integer of 1 to 15), -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -COO-, -OCO-, or -((CH ₂ ) _a1 -A ₁ ) _m1 -. Among these, a1's each independently represent an integer of 1 to 15, A ₁ 's each independently represent an oxygen atom or -COO-, and m ₁ is 1 to 2. X ³ represents a single bond, -CONH-, -NHCO-, -CON(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -COO-, or -OCO-. X ⁴ represents -CONH-, -NHCO-, -O-, -COO-, or -OCO-.
_G1 and _G2 each independently represent a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms. Any hydrogen atom on the cyclic group may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxy group having 1 to 3 carbon atoms, or a fluorine atom. k represents 0 or 1, m and n each independently represent an integer of 0 to 3, and the sum of m and n is 1 to 4.
^R1 represents 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. Any hydrogen forming ^R1 may be substituted with fluorine.
^R2 represents an alkyl group having 1 to 20 carbon atoms or an alkoxyalkyl group having 2 to 20 carbon atoms, and any hydrogen atom forming ^R2 may be substituted with a fluorine atom. ^R3 represents a structure having a steroid skeleton. The polymer (A) is such that _X1 is a tetravalent organic group, and Y The liquid crystal aligning agent according to any one of claims _{1 to 8,} wherein the repeating unit (c)) selected from the group consisting of the repeating unit represented by the formula (1) and the repeating unit represented by the formula (2) is a divalent organic group derived from a diamine selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylether, 4,4'-diaminoazobenzene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]ether, 4,4'-bis(4-aminophenoxy)biphenyl, diamine represented by the following formula (H), and diamine represented by the following formula (H2) to (H3), and the content of the repeating unit (c) is 5 mol% or more in total with respect to the total repeating units of the polymer (A).

^R3 is a structure represented by -NRCO-, -COO-, -NRCONR-, or -(CH ₂ ) _n - (wherein n is an integer of 2 to 20), and any -CH ₂ - may be replaced by -O-, -COO-, -ND-, -NRCO-, -NRCONR-, -NRCOO-, or -OCOO-. D represents a thermally detachable group, and R represents a hydrogen atom or a monovalent organic group.), R ⁴ is a single bond or a benzene ring, and any hydrogen atom on the benzene ring may be replaced by a monovalent organic group.

X ₁ represents -CO-, -O-, -COO-, -L ₁ -R-L ₂ - (L ₁ and L ₂ are each independently a single bond, an oxygen atom, or -COO-, and R is -(CH ₂ ) _n - (n is an integer of 1 to 12)), or -NRCO- (R represents a hydrogen atom or a methyl group), and X ₂ represents a single bond, -NRCO- (R represents a hydrogen atom or a methyl group), or -COO-. n represents an integer of 1 or 2. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group.

In the formula, two Xs each independently represent -O-, -COO-, -NHCO-, -C(=O)-, or -( _CH2 ) _n- (n is an integer of 1 to 12), _L1 and _L2 each independently represent a single bond, -O-, or -COO-, and R represents _-CH2- , -( _CH2 ) _n- (n is an integer of 2 to 12), or a group in which any _CH2 in the -( _CH2 ) _n- is replaced with an oxygen atom. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group. The polymer (A) contains one or more repeating units (repeating units (c)) selected from the group consisting of repeating units represented by the above formula (1) and repeating units represented by the above formula (2), in which Y ₁ is a divalent organic group derived from a diamine selected from the group consisting of p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 4,4'-diaminoazobenzene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]ether, 4,4'-bis(4-aminophenoxy)biphenyl, diamines represented by the following formula (H), and diamines represented by the following formulas (H2) to (H3), and the content of the repeating units (c) is 5 mol% or more in total with respect to the total repeating units of the polymer (A). The liquid crystal aligning agent according to any one of claims 1 to 9.

^R3 is a structure represented by -NRCO-, -COO-, -NRCONR-, or -(CH ₂ ) _n - (wherein n is an integer of 2 to 20), and any -CH ₂ - may be replaced by -O-, -COO-, -ND-, -NRCO-, -NRCONR-, -NRCOO-, or -OCOO-. D represents a thermally detachable group, and R represents a hydrogen atom or a monovalent organic group.), R ⁴ is a single bond or a benzene ring, and any hydrogen atom on the benzene ring may be replaced by a monovalent organic group.

X ₁ represents -CO-, -O-, -COO-, -L ₁ -R-L ₂ - (L ₁ and L ₂ are each independently a single bond, an oxygen atom, or -COO-, and R is -(CH ₂ ) _n - (n is an integer of 1 to 12)), or -NRCO- (R represents a hydrogen atom or a methyl group), and X ₂ represents a single bond, -NRCO- (R represents a hydrogen atom or a methyl group), or -COO-. n represents an integer of 1 or 2. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group.

In the formula, two Xs each independently represent -O-, -COO-, -NHCO-, -C(=O)-, or -( _CH2 ) _n- (n is an integer of 1 to 12), _L1 and _L2 each independently represent a single bond, -O-, or -COO-, and R represents _-CH2- , -( _CH2 ) _n- (n is an integer of 2 to 12), or a group in which any _CH2 in the -( _CH2 ) _n- is replaced with an oxygen atom. Any hydrogen atom on the benzene ring may be replaced with a monovalent organic group. The polymer (A) includes at least one repeating unit (b) selected from the group consisting of repeating units represented by the formula (1 ₎ and repeating units represented by the formula (2), in which X ₁ is a tetravalent organic group and Y 1 is a divalent organic group derived from a diamine selected from the group consisting of diamines having a radical initiation function and diamines having a photopolymerizable group at their ends, and the content of the repeating unit (b) is 1 mol% or more in total with respect to the total repeating units of the polymer (A). The liquid crystal aligning agent according to any one of claims 1 to 10. The liquid crystal aligning agent according to claim 11, wherein the polymer (A) contains the repeating unit (a) defined in claim 7 and the repeating unit (b) defined in claim 11, and the upper limit of the content of the repeating unit (a) and the repeating unit (b) is 99 mol % or less, based on the total repeating units of the polymer (A). The polymer (A) includes one or more repeating units (repeating units (b)) selected from the group consisting of repeating units represented by the formula (1) and repeating units represented by the formula (2), in which _Y1 is a divalent organic group derived from a diamine selected from the group consisting of diamines having a radical initiation function and diamines having a photopolymerizable group at a terminal thereof, and the content of the repeating units (b) is 1 mol% or more in total relative to the total repeating units of the polymer (A). The liquid crystal aligning agent according to any one of claims 1 to 12. The liquid crystal alignment agent according to any one of claims 1 to 13, further comprising a polyorganosiloxane, the polyorganosiloxane having at least one of an oxetanyl group and an oxiranyl group. The liquid crystal aligning agent according to any one of claims 1 to 14, wherein the component (A) is composed of two or more types of polymer (A). The liquid crystal aligning agent according to any one of claims 1 to 15, wherein the content of the compound (B) is 0.1 to 40 parts by mass per 100 parts by mass of the component (A). A liquid crystal alignment film obtained from the liquid crystal alignment agent according to any one of claims 1 to 16. A liquid crystal display element comprising the liquid crystal alignment film according to claim 17.