JPWO2015152014A1 - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

Liquid crystal aligning agent containing the following (A) component and (B) component. (A) Component: Compound represented by Formula [1]. [Chemical formula 1] (The symbols in the formula are as described in the specification). (B) component: At least 1 type of polymer chosen from a polyimide precursor and a polyimide.

Description

  The present invention relates to a liquid crystal alignment treatment agent used for manufacturing a liquid crystal display element, a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent, and a liquid crystal display element using the liquid crystal alignment film.

  Liquid crystal display elements are now widely used as display devices that are thin and light. Usually, in this liquid crystal display element, a liquid crystal alignment film is used to determine the alignment state of the liquid crystal. Most of the liquid crystal alignment films, except for some vertical alignment type liquid crystal display elements, are produced by performing some kind of alignment treatment on the surface of the liquid crystal alignment film formed on the electrode substrate.

  As a method for aligning the liquid crystal alignment film, a method generally used at present is a method of performing a so-called rubbing process in which the surface of the liquid crystal alignment film is rubbed with a cloth made of rayon or the like under pressure. . A method of using a liquid crystal alignment treatment agent containing a specific thermally crosslinkable compound together with at least one polymer of a polyimide precursor or a polyimide for scraping of a liquid crystal alignment film accompanying rubbing treatment (for example, Patent Documents) 1) and a method using a liquid crystal aligning agent containing an epoxy group-containing compound (see, for example, Patent Document 2), and a method for improving rubbing resistance by using a curing agent has been proposed.

  In recent years, attention has been focused on a photo-alignment treatment method for controlling the alignment state of liquid crystal by irradiating polarized ultraviolet rays as an alternative to the rubbing treatment method. As a liquid crystal alignment treatment method using a photo-alignment treatment method, a method utilizing a photoisomerization reaction, a photocrosslinking reaction, or a photolysis reaction has been proposed (see, for example, Patent Document 3 and Non-Patent Document 1).

Japanese Patent Laid-Open No. 9-185065 JP-A-9-146100 JP-A-9-297313

"Liquid crystal alignment film" Kidowaki, Ichimura Functional Materials November 1997, Vol. 17, no. 11, pages 13-22

  In recent years, in order to reduce the weight of large TVs and smartphones, a process of physically polishing the glass surface of the manufactured liquid crystal display element has been performed. In this step, the liquid crystal alignment film on the column spacer and the liquid crystal alignment film on the opposite substrate are rubbed, and the liquid crystal alignment film is peeled off. The peeled liquid crystal alignment film becomes a foreign substance, and a display defect of the liquid crystal display element is likely to occur. In addition, when the liquid crystal display element is used for a smartphone or a tab red terminal, a physical impact such as finger pressing is applied to the liquid crystal display element. Therefore, as described above, peeling of the liquid crystal alignment film and generation of foreign matters may occur. It tends to be a problem as a display defect.

  In addition, when using a liquid crystal display element for smartphones or tablet terminals, the width of the sealant used for bonding the substrates of the liquid crystal display element is made narrower than before in order to secure as many display surfaces as possible. There is a need. In such a case, in order to prevent damage to the liquid crystal display element, it is necessary to increase the adhesiveness (also referred to as adhesion) between the liquid crystal alignment film and the sealing agent as compared with the conventional case.

  In addition, in the photo-alignment treatment method which is attracting attention as a new alignment treatment method in place of the rubbing treatment method in the future, when the liquid crystal alignment treatment method uses a photolysis reaction, the glass substrate polishing treatment or touch panel Peeling of the liquid crystal alignment film and generation of foreign matters are likely to occur due to finger pressing (generally referred to as physical impact) in use.

  Then, this invention aims at providing the liquid-crystal aligning agent which has the said characteristic. That is, an object of the present invention is to provide a liquid crystal alignment film capable of suppressing the peeling of the liquid crystal alignment film and the generation of foreign matters due to a physical impact on the liquid crystal display element. Furthermore, it aims at providing the liquid crystal aligning film which has high adhesiveness of a liquid crystal aligning film and a sealing agent, and can make the intensity | strength of a liquid crystal display element high. In particular, an object of the present invention is to provide a liquid crystal alignment film that can improve these characteristics when a photo-alignment treatment method, particularly, photodecomposition reaction is used. In addition, it aims at providing the liquid crystal display element which has the said liquid crystal aligning film, and the liquid-crystal aligning agent which can provide the said liquid crystal aligning film.

  As a result of intensive studies, the present inventors have found that a liquid crystal aligning agent having a compound having a specific structure and at least one polymer selected from a polyimide precursor and a polyimide is extremely suitable for achieving the above object. The present invention has been found by finding it effective.

That is, the present invention has the following gist.
(1) Liquid crystal aligning agent containing the following (A) component and (B) component.

(A) Component: Compound represented by Formula [1].

(W ¹ represents an organic group having 1 to 30 carbon atoms, and W ² represents —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CON (CH ₃ ) —, _{-N (CH 3) CO -,} - COO -, - OCO- and represents at least one linking group selected from -S-, n is an integer of 1-6).

(B) component: At least 1 type of polymer chosen from a polyimide precursor and a polyimide.

(2) The liquid crystal aligning agent according to (1), wherein W ¹ in the formula [1] is at least one structure selected from the following formulas [1a] and [1b].

(W ³ and W ⁵ each independently represent a benzene ring or a cyclohexane ring, and W ⁴ represents a single bond, —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, At least one linking group selected from —CON (CH ₃ ) —, —N (CH ₃ ) CO—, —COO—, —OCO—, and —S—, q represents an integer of 0 to 4; W ⁶ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms, and the hydrogen atom bonded to any of these carbon atoms is a halogen-containing alkyl group. A group, a halogen atom, a hydroxyl group (OH group) and a carboxyl group (COOH group), and * represents a bond with W ² .

(3) The liquid crystal aligning agent according to (2), wherein the compound of component (A) is at least one compound selected from the following formulas [1-1] to [1-8].

(4) The polymer of the component (B) is obtained using a diamine component containing at least one diamine compound selected from diamine compounds represented by the following formulas [2a-1] to [2a-3]. The liquid crystal aligning agent according to any one of (1) to (3), which is at least one polymer selected from a polyimide precursor and a polyimide.

(X ¹ , X ³ and X ⁷ , and X ⁸ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, -O-, -N (R ¹ )-(R ¹ is a hydrogen atom or carbon indicates the number 1-3 alkyl ^{group), - CON (R 2)} - (R 2 represents a hydrogen atom or an alkyl group having 1 to 3 carbon ^{atoms), - N (R 3)} CO- (R 3 is hydrogen Represents an atom or an alkyl group having 1 to 3 carbon atoms), represents at least one organic group selected from —CH ₂ O—, —COO— and —OCO—, and represents X ² , X ⁴ and X ⁶ , and X ⁹ each independently represents a single bond or an alkylene group having 1 to 10 carbon atoms, X ^a and X ^e each independently represent a hydrogen atom or an organic group having 1 to 20 carbon atoms, and X ^b , X ^{e c} and X ^f are each independently a protecting group to replace a hydrogen atom by heat, Represents an integer of 1 or 2, p represents an integer of 1 to 4, q is an integer of 1 to 4, ^{X 5} represents a single bond or an alkylene group having 1 to 10 carbon atoms, r is 1 4 represents an integer, X ^d represents a single bond or an organic group having 1 to 20 carbon atoms, n represents an integer of 1 to 4, s represents an integer of 1 to 4, and t represents an integer of 1 to 4. A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(5) In the diamine compound represented by the formula [2a-1] to the formula [2a-3], X ^b , X ^c and X ^f are each independently represented by the following formula [a-1] to formula [a The liquid-crystal aligning agent as described in (4) which is a diamine compound which is a protecting group which has a structure shown by -6].

(R ¹ represents an alkyl group having 1 to 5 carbon atoms).

(6) The diamine compound represented by the formula [2a-1] to the formula [2a-3] is a diamine compound represented by the following formula [2a-4] to the formula [2a-12]. Liquid crystal alignment treatment agent.

(R ^{1 to} R ¹⁴ each independently represents at least one structure selected from the structures represented by the formulas [a-1] to [a-6], and A ^{1 to} A ¹⁸ are each independently selected. A hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(7) The polymer of the component (B) is at least one polymer selected from a polyimide precursor and a polyimide obtained using a diamine component containing a diamine compound represented by the following formula [2b] ( The liquid-crystal aligning agent in any one of 1)-(6).

(Y ¹ and Y ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —S—, —N (R ¹ ) — (R ¹ is a hydrogen atom or 1 to 3 represents an alkyl group), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom or carbon) Represents an alkyl group having a number of 1 to 3, and represents at least one organic group selected from —CH ₂ O—, —COO—, and —OCO—, and Y ² and Y ⁶ each independently represent carbon number 1 -10 represents an alkylene group, Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, Y ⁴ represents an oxygen atom or a sulfur atom, and A ¹ and A ² represent Each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(8) The liquid crystal aligning agent according to (7), wherein the diamine compound represented by the formula [2b] is a diamine compound represented by the following formula [2b-1] to formula [2b-3].

(A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(9) The polymer of the component (B) is obtained using a diamine component containing at least one diamine compound selected from diamine compounds represented by the following formulas [2c-1] to [2c-3]. The liquid crystal aligning agent according to any one of (1) to (8), which is at least one polymer selected from polyimide precursors and polyimides.

(X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring, X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms, and X ² represents a hydrogen atom. In the case, X ¹ represents a nitrogen-containing aromatic heterocyclic ring, and when X ² is a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms, X ¹ represents a benzene ring, and X ³ and X ⁷ Each independently represents an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings, and X ⁴ and X ⁶ each independently represent a hydrogen atom or 1 to 5 carbon atoms. X ⁵ represents an alkylene group having 2 to ⁵ carbon atoms or a biphenyl group, m represents an integer of 0 or 1, and X ⁸ and X ¹⁰ each independently represent the following formula [c-1 ] and represents at least one structure selected from the formula [c-2], X Represents an alkylene group or a benzene ring having 1 to 5 carbon atoms, A ¹ to A ⁶ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(10) The diamine compound represented by the formula [2c-1] to the formula [2c-3] is a diamine compound represented by the following formula [2c-4] to the formula [2c-7]. Liquid crystal alignment treatment agent.

(R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, n in Formula [2c-7] represents an integer of 1 to 10, and A ^{1 to} A ⁸ each independently represents a hydrogen atom or An alkyl group having 1 to 5 carbon atoms).

(11) The polymer of the component (B) is at least one polymer selected from a polyimide precursor and a polyimide obtained using a diamine component containing a diamine compound represented by the following formula [2d] ( The liquid-crystal aligning agent in any one of 1)-(10).

(X represents at least one structure selected from the following formulas [d-1] to [d-8], and A ¹ and A ² each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Show).

(N represents an integer of 1 to 5).

(12) The polymer of the component (B) is at least one selected from a polyimide precursor and a polyimide obtained by using a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula [3] The liquid-crystal aligning agent in any one of (1)-(11) which is a polymer of these.

(Z represents at least one structure selected from the following formulas [3a] to [3q]).

(Z ^{1 to} Z ⁴ represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring, and may be the same or different, and in the formula [3g], Z ⁵ and Z ⁶ are A hydrogen atom or a methyl group, which may be the same or different.

(13) In the tetracarboxylic acid component, Z in the formula [3] is represented by the formula [3a], the formula [3e] to the formula [3g], the formula [3l], the formula [3m], or the formula [3p]. The liquid crystal aligning agent according to (12), which is a tetracarboxylic acid component having at least one structure selected from the structures shown.

(14) The liquid crystal according to any one of (1) to (13), wherein the compound of the component (A) is 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the polymer of the component (B). Alignment treatment agent.

(15) The liquid crystal aligning agent according to any one of (1) to (14), wherein the polymer of the component (B) is a polyamic acid alkyl ester.

(16) Any one of (1) to (15) containing at least one solvent selected from N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and γ-butyrolactone as a solvent for the liquid crystal aligning agent A liquid crystal alignment treatment agent according to claim 1.

(17) As a solvent for the liquid crystal aligning agent, 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate and dipropylene The liquid crystal aligning agent according to any one of (1) to (16), which contains at least one solvent selected from glycol dimethyl ether.

(18) A liquid crystal alignment film obtained from the liquid crystal aligning agent according to any one of (1) to (17).

(19) A liquid crystal alignment film obtained by an inkjet method using the liquid crystal aligning agent according to any one of (1) to (17).

(20) A liquid crystal alignment film obtained by irradiating the liquid crystal alignment film according to (18) or (19) with polarized radiation.

(21) A liquid crystal display device having the liquid crystal alignment film according to any one of (18) to (20).

  The liquid crystal aligning agent containing a compound having a specific structure used in the present invention and at least one polymer selected from a polyimide precursor and a polyimide is a liquid crystal alignment film peeled off due to physical impact on the liquid crystal display element. A liquid crystal alignment film that can suppress the generation of foreign matters can be obtained. Furthermore, the liquid crystal alignment film which can improve the adhesiveness of a liquid crystal aligning film and a sealing agent and can make the intensity | strength of a liquid crystal display element high can be obtained. In particular, it is useful for a liquid crystal alignment film for photo-alignment treatment obtained by irradiating polarized radiation. Therefore, the liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the present invention has excellent reliability, and is suitable for a large-screen high-definition liquid crystal television, a small and medium-sized smartphone, a tablet terminal, and the like. Can be used.

FIG. 1 shows the structure of a test cell produced in “Evaluation of Adhesiveness between Sealant and Substrate (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealant)”.

  The present invention is described in detail below.

  The present invention is a liquid crystal aligning agent containing the following components (A) and (B), a liquid crystal aligning film obtained using the liquid crystal aligning agent, and a liquid crystal display element having the liquid crystal aligning film. is there.

Component (A): a compound represented by the following formula [1] (also referred to as a specific compound).

(X ¹ represents an organic group having 1 to 30 carbon atoms, and X ² represents —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CON (CH ₃ ) —, _{-N (CH 3) CO -,} - COO -, - OCO- and represents at least one linking group selected from -S-, n is an integer of 1-6).

Component (B): at least one polymer selected from a polyimide precursor and a polyimide (also referred to as a specific polyimide polymer).

  The reason why the problem of the present invention is solved in the liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention is not necessarily clear, but is considered as follows.

The particular compound of the formula [1], by heat, the unsaturated double bond that reacts with the carbonyl group contained in the crosslinking reaction and the specific polymer (-COOH group) ^(-X ₂ -CH = CH 2 group) Have Therefore, the reaction occurs in the firing step when the liquid crystal alignment film is produced, and the film strength of the liquid crystal alignment film can be increased. Therefore, it is possible to suppress peeling of the liquid crystal alignment film and generation of foreign matters due to physical impact on the liquid crystal display element.

In addition, the unsaturated double bond of the specific compound is a general unsaturated double bond, for example, an acrylic group (—O—C (═O) —CH═CH ₂ group) or a methacryl group (—O—C). Thermal stability of unsaturated double bond sites (-CH = CH ₂ and -C (-CH ₃ ) = CH _{2 in the} above) compared to (= O) -C (-CH ₃ ) = CH ₂ group) High nature. That is, the unsaturated double bond site of the specific compound has higher thermal stability than a general compound. Therefore, in the present invention, when a specific compound is used, an unsaturated double bond site is likely to remain even after the firing step in producing the liquid crystal alignment film. As a result, the remaining part and the sealing agent component chemically react with each other by the curing process of the sealing agent when producing the liquid crystal display element, that is, irradiation and baking of ultraviolet rays, and the liquid crystal alignment film and the sealing agent Adhesion can be improved.

  In addition, the liquid-crystal aligning agent in this invention is useful with respect to the photo-alignment processing method using the photodecomposition reaction using the polyimide-type resin which has alicyclic structures, such as a cyclobutane ring. Specifically, in this photo-alignment treatment method, a maleimide compound having an unsaturated double bond is generated from a cyclobutane ring by a photolysis reaction. Therefore, the chemical reaction with the specific compound is promoted, and the above effect becomes higher.

  In view of the above, the liquid crystal alignment treatment agent of the present invention can suppress the peeling of the liquid crystal alignment film and the generation of foreign substances due to physical impact on the liquid crystal display element. A liquid crystal alignment film that can increase the adhesion and increase the strength of the liquid crystal display element can be obtained.

<Specific compounds>
The specific compound used in the present invention is a compound represented by the following formula [1].

W ¹ represents an organic group having 1 to 30 carbon atoms. Of these, a cyclic group having 1 to 18 carbon atoms or an aliphatic monovalent hydrogen group is preferable from the viewpoint of liquid crystal orientation.

  Specific examples thereof include benzene ring, naphthalene ring, tetrahydronaphthalene ring, azulene ring, indene ring, fluorene ring, anthracene ring, linear or branched alkyl group having 1 to 18 carbon atoms, and unsaturated alkyl group having 1 to 18 carbon atoms. Group, cyclopropane ring, cyclobutane ring, cyclopentane ring, cyclohexane ring, cycloheptane ring, cyclooctane ring, cyclononane ring, cyclodecane ring, cycloundecane ring, cyclododecane ring, cyclotridecane ring, cyclotetradecane ring, cyclopentadecane ring , Cyclohexadecane ring, cycloheptadecane ring and cyclooctadecane ring. Especially, a benzene ring, a naphthalene ring, a C1-C18 unsaturated alkyl group, a C1-C18 linear alkyl group, a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring are preferable. In addition, the hydrogen atom bonded to these arbitrary carbon atoms may be replaced with a halogen-containing alkyl group, a halogen atom, a hydroxyl group (OH group), or a carbonyl group.

W ² is _{-O -, - NH -, -} N (CH 3) -, - CONH -, - NHCO -, - CON (CH 3) -, - N (CH 3) CO -, - COO -, - OCO And at least one linking group selected from-and -S-. Of these, -O-, -COO-, and -CONH- are preferred from the viewpoint of ease of production of the specific compound.

  n shows the integer of 1-6. Especially, the integer of 1-4 is preferable from a viewpoint of the ease of manufacture of a specific compound.

As a more preferable specific compound, W ¹ in the formula [1] is a specific compound having at least one structure selected from the following formula [1a] and formula [1b].

W ³ and W ⁵ each independently represent a benzene ring or a cyclohexane ring.

W ⁴ represents a single bond, —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CON (CH ₃ ) —, —N (CH ₃ ) CO—, —COO—. , -OCO- and -S- represents at least one linking group. Of these, a single bond, —O—, —COO—, and —CONH— are preferable from the viewpoint of easy production of the specific compound.

  q shows the integer of 0-4. Especially, the integer of 0-2 is preferable from a viewpoint of the ease of manufacture of a specific compound.

W ⁶ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms. Especially, from a viewpoint of the ease of manufacture of a specific compound, a C1-C6 alkylene group, a C1-C6 alkenylene group, or a C1-C6 alkynylene group is preferable. Note that hydrogen atoms bonded to these arbitrary carbon atoms may be replaced with a halogen-containing alkyl group, a halogen atom, a hydroxyl group (OH group), or a carboxyl group (COOH group). * Represents a bond with W ² .

  Specific examples of the specific compound include compounds represented by the following formulas [1-1] to [1-8].

  Especially, since the effect which expresses the effect of this invention is high, the compound of Formula [1-3] is preferable.

  The specific compound used in the present invention may be one type or the like depending on the solubility of the specific compound in the solvent, the coating property of the liquid crystal aligning agent, the liquid crystal alignment property and the voltage holding ratio when the liquid crystal alignment film is used. Two or more types can be mixed and used.

<Specific polyimide polymer>
The specific polyimide polymer used in the present invention is at least one polymer selected from a polyimide precursor and polyimide. Among these, a polyimide precursor or polyimide obtained by reacting a diamine component (also referred to as a diamine compound) and a tetracarboxylic acid component (also referred to as a tetracarboxylic acid compound) is preferable.

  The polyimide precursor has a structure represented by the following formula [A].

(R ¹ is a tetravalent organic group, R ² is a divalent organic group, A ¹ and A ² each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and A ³ And A ⁴ each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an acetyl group, and n represents a positive integer).

  Examples of the diamine component include diamine compounds having two primary or secondary amino groups in the molecule.

  Examples of the tetracarboxylic acid component include tetracarboxylic acid compounds, tetracarboxylic dianhydrides, tetracarboxylic acid dihalide compounds, tetracarboxylic acid dialkyl ester compounds, and tetracarboxylic acid dialkyl ester dihalide compounds.

In order to obtain a polyamic acid in which A ¹ and A ² are hydrogen atoms, a diamine compound having two primary or secondary amino groups in the molecule, a tetracarboxylic acid compound or a tetracarboxylic acid anhydride It can be obtained by reacting.

In order to obtain a polyamic acid alkyl ester in which A ¹ and A ² are alkyl groups having 1 to 5 carbon atoms, the diamine compound, a tetracarboxylic acid dihalide compound, a tetracarboxylic acid dialkyl ester compound, or a tetracarboxylic acid dialkyl ester di It can be obtained by reacting with a halide compound. Further, the polyamic acid obtained by the method, it is also possible to introduce an alkyl group of 1 to 5 carbon atoms for A ¹ and A ² of the formula [A].

  Although there is no restriction | limiting in particular in the diamine component and tetracarboxylic-acid component used in order to produce a specific polyimide-type polymer, From a viewpoint which can improve the afterimage characteristic by the alternating current drive in a liquid crystal display element, following formula [2a-1]-a formula [ It is preferable to use a diamine compound represented by 2a-3] (also collectively referred to as a specific diamine compound (1)).

X ¹ is a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —N (R ¹ ) — (R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —CH ₂ represents at least one organic group selected from ₂ O—, —COO—, and —OCO—. Of these, a single bond, —O—, —CONH—, —NHCO—, —COO— or —OCO— is preferable.

X ² represents a single bond or an alkylene group having 1 to 10 carbon atoms. Among these, a single bond or an alkylene group having 1 to 5 carbon atoms is preferable.

Xa represents ^a hydrogen atom or an organic group having 1 to 20 carbon atoms, more preferably a hydrogen atom or an organic group having 1 to 10 carbon atoms. The organic group having 1 to 10 carbon atoms is preferably — (CH ₂ ) _n —COO-tBu (n represents an integer of 1 to 5, and tBu represents a tert-butyl group).

The structure of ^Xb is not particularly limited as long as it is a protecting group that can be replaced by a hydrogen atom by heat, but the structure in which the elimination reaction proceeds efficiently at a baking temperature of 150 ° C. to 300 ° C. when the liquid crystal alignment film is produced. preferable. Specifically, it is preferable to use a protecting group having a structure represented by the following formulas [a-1] to [a-6].

(R ¹ represents an alkyl group having 1 to 5 carbon atoms).

  Among them, it is preferable to use a protecting group having a structure represented by the formula [a-1] or the formula [a-6].

m represents an integer of 1 or 2, in which the substituents ^{X a} when m in the formula [2a-1] is 2 no.

  p shows the integer of 1-4. Especially, 1-3 are preferable from the point of the availability of a raw material and the ease of a synthesis | combination. More preferably, it is 1-2.

  q shows the integer of 1-4. Especially, 1-3 are preferable from the point of the availability of a raw material and the ease of a synthesis | combination. More preferably, it is 1-2.

X ³ and X ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, -O-, -N (R ¹ )-(R ¹ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. ^{shown), - CON (R 2)} - (R 2 represents a hydrogen atom or an alkyl group having 1 to 3 carbon ^{atoms), - N (R 3)} CO- (R 3 is a hydrogen atom or 1 to 3 carbon atoms An alkyl group), at least one organic group selected from —CH ₂ O—, —COO—, and —OCO—. Of these, a single bond, —O—, —CONH—, —NHCO—, —COO— or —OCO— is preferable.

X ⁴ and X ⁶ each independently represent a single bond or an alkylene group having 1 to 10 carbon atoms. Among these, a single bond or an alkylene group having 1 to 5 carbon atoms is preferable.

X ⁵ represents a single bond or an alkylene group having 1 to 10 carbon atoms. Among these, a single bond or an alkylene group having 1 to 5 carbon atoms is preferable.

The structure of ^Xc is not particularly limited as long as it is a protecting group that can be replaced by a hydrogen atom by heat, but a structure in which the elimination reaction proceeds efficiently at a baking temperature of 150 ° C to 300 ° C when producing a liquid crystal alignment film. preferable. Specifically, it is preferable to use a protecting group having a structure represented by the formulas [a-1] to [a-6]. Among them, it is preferable to use a protecting group having a structure represented by the formula [a-1] or the formula [a-6].

  r shows the integer of 1-4. Especially, 1-3 are preferable from the point of the availability of a raw material and the ease of a synthesis | combination. More preferably, it is 1-2.

X ⁸ is a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —N (R ¹ ) — (R ¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —CH ₂ represents at least one organic group selected from ₂ O—, —COO—, and —OCO—. Of these, a single bond, —O—, —CONH—, —NHCO—, —COO— or —OCO— is preferable.

X ⁹ represents a single bond or an alkylene group having 1 to 10 carbon atoms, preferably a single bond or an alkylene group having 1 to 5 carbon atoms.

X ^d represents a single bond or an organic group having 1 to 20 carbon atoms. Among these, a single bond or an organic group having 1 to 10 carbon atoms is preferable. More preferably, they are a single bond or a carbon atom (> CH-).

^Xe represents a hydrogen atom or an organic group having 1 to 20 carbon atoms. At that time, ^{X e} is not when ^{X d} is a single bond. Of these, a hydrogen atom or -NH-COO-tBu (tBu represents a tert-butyl group) is preferable.

^Xf is a protecting group for a carboxyl group, and the structure is not particularly limited as long as it is a protecting group that can be replaced by a hydrogen atom by heating. A structure in which the elimination reaction proceeds efficiently at a firing temperature of 150 ° C. to 300 ° C., which is a firing temperature when the liquid crystal alignment film is produced, is preferable. Specifically, it is preferable to use a protecting group having a structure represented by the formulas [a-1] to [a-6]. Among them, it is preferable to use a protecting group having a structure represented by the formula [a-1] or the formula [a-6].

  n shows the integer of 1-4. Especially, 1-3 are preferable from the point of the availability of a raw material and the ease of a synthesis | combination. More preferably, it is 1-2.

  s shows the integer of 1-4, and 1-3 are preferable especially from the point of the availability of a raw material and the ease of a synthesis | combination. More preferably, it is 1-2.

  t represents an integer of 1 to 4, and among these, 1 to 3 are preferable from the viewpoint of availability of raw materials and ease of synthesis. More preferably, it is 1-2.

A ^{1 to} A ⁶ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  Specific examples of the diamine compound (1) include diamine compounds represented by the following formulas [2a-4] to [2a-12].

(R ^{1 to} R ⁷ each independently represents at least one structure selected from the structures represented by the formulas [a-1] to [a-6], and A ^{1 to} A ¹⁰ are each independently selected. A hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(R ^{8 to} R ¹⁴ each independently represents at least one structure selected from the structures represented by the formulas [a-1] to [a-6], and A ^{11 to} A ¹⁸ are each independently selected. A hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

  Among these, as the specific diamine compound (1), the above-described effects, that is, the effect of improving the afterimage characteristics due to alternating current driving in the liquid crystal display element are further enhanced, so that the formulas [2a-4] to [2a -8] is preferably used. The formula [2a-4], the formula [2a-6] or the formula [2a-8] is more preferable.

  Furthermore, as specific diamine compound (1), the diamine compound shown by following formula [2a-13] and formula [2a-14] can also be used.

(R ^{15 to} R ¹⁸ each independently represents at least one structure selected from the structures represented by the formulas [a-1] to [a-6], and A ¹⁹ and A ²⁰ are each independently selected. A hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

  The specific diamine compound (1) in the specific polyimide polymer is preferably 5 mol% to 40 mol% in 100 mol% of all diamine components. Especially, 5 mol%-30 mol% are preferable. More preferably, it is 5 mol%-20 mol%.

  In addition, the specific diamine compound (1) depends on the properties such as the solubility of the specific polyimide polymer in the solvent, the coating property of the liquid crystal alignment treatment agent, and the liquid crystal alignment property and voltage holding ratio when used as a liquid crystal alignment film. One kind or a mixture of two or more kinds may be used.

  As the specific polyimide-based polymer, it is preferable to use a diamine compound (also referred to as a specific diamine compound (2)) represented by the following formula [2b] from the viewpoint of improving the charge relaxation characteristics in the liquid crystal display element.

Y ¹ and Y ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —S—, —N (R ¹ ) — (R ¹ is a hydrogen atom or 1 to 3 carbon atoms). -CON (R ² )-(R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom or carbon number) 1 to 3 alkyl groups), at least one organic group selected from —CH ₂ O—, —COO—, and —OCO—. Of these, a single bond, —O—, —S—, —OCO— or —COO— is preferable. More preferably, it is a single bond, —O— or —S— which is a structure which is as flexible as possible and has a small steric hindrance in terms of liquid crystal orientation and film hardness.

Y ² and Y ⁶ each independently represent an alkylene group having 1 to 10 carbon atoms. Among these, an alkylene group having 1 to 3 carbon atoms is preferable, and the structure may be either a straight chain or a branched chain. Specifically, from the viewpoint of liquid crystal alignment properties and film hardness of the liquid crystal alignment film, a methylene group (—CH ₂ —), an ethylene group (—CH ₂ CH ₂ ) having a structure with a free rotation portion and small steric hindrance. -), propylene (- _{(CH 2) 3} -) or an isopropyl group _{(-C (CH 2) 2 -} ) is preferred.

Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Of these, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable. Particularly preferred is a hydrogen atom.

Y ⁴ represents an oxygen atom or a sulfur atom. Of these, oxygen atoms are preferred from the viewpoint of the film hardness of the liquid crystal alignment film.

Preferred combinations of Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ , Y ⁶ and Y ^{7 in} the formula [2b] are as shown in Table 1 below.

  Especially, Formula [2-1b], Formula [2-2b], Formula [2-4b], Formula [2-5b], Formula [2-7b], Formula [2-8b], Formula [2-10b ] And a combination represented by formula [2-11b] are preferable.

A ¹ and A ² each independently represent a hydrogen atom or an alkylene group having 1 to 5 carbon atoms.

  As a more specific specific diamine compound (2), from the viewpoint that the above effect, that is, the effect of improving the charge relaxation property in the liquid crystal display element becomes higher, the following formulas [2b-1] to [2b-3] It is preferable to use a diamine compound represented by the formula:

(A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

  The specific diamine compound (2) in the specific polyimide polymer is preferably 10 mol% to 100 mol% in 100 mol% of all diamine components. Especially, 20 mol%-100 mol% are preferable. More preferably, it is 30 mol%-100 mol%.

  In addition, the specific diamine compound (2) depends on the properties such as the solubility of the specific polyimide polymer in the solvent, the coating property of the liquid crystal alignment treatment agent, and the liquid crystal alignment property and voltage holding ratio when used as a liquid crystal alignment film. One kind or a mixture of two or more kinds may be used.

  The specific polyimide-based polymer includes a diamine compound represented by the following formulas [2c-1] to [2c-3] (also referred to as a specific diamine compound (3)) from the viewpoint of improving charge relaxation characteristics in a liquid crystal display element. Is preferably used.

X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocycle.

X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms.

When X ² is a hydrogen atom, X ¹ represents a nitrogen-containing aromatic heterocyclic ring, and when X ² is a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms, X ¹ represents a benzene ring. Indicates.

X ³ and X ⁷ each independently represent an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings.

X ⁴ and X ⁶ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

X ⁵ represents an alkylene group having 2 to ⁵ carbon atoms or a biphenyl group.

  m represents an integer of 0 or 1.

X ⁸ and X ¹⁰ each independently represent at least one structure selected from structures represented by the following formulas [c-1] and [c-2].

X ⁹ represents an alkylene group having 1 to 5 carbon atoms or a benzene ring.

A ^{1 to} A ⁶ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  Specific examples of the diamine compound (3) include diamine compounds represented by the following formulas [2c-4] to [2c-7].

R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  n shows the integer of 1-10.

A ^{1 to} A ⁸ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  Among these, as the specific diamine compound (3), the above-described effect, that is, the effect of improving the charge relaxation property in the liquid crystal display element is further enhanced, so that the above formulas [2c-4] and [2c-6] It is preferable to use a diamine compound represented by the formula [2c-7].

  The specific diamine compound (3) in the specific polyimide polymer is preferably 1 mol% to 95 mol% in 100 mol% of all diamine components. Especially, 5 mol%-95 mol% are preferable. More preferably, it is 20 mol% to 80 mol%.

  In addition, the specific diamine compound (3) depends on the properties such as the solubility of the specific polyimide polymer in the solvent, the coating property of the liquid crystal alignment treatment agent, and the liquid crystal alignment property and voltage holding ratio when used as a liquid crystal alignment film. One kind or a mixture of two or more kinds may be used.

  As the specific polyimide polymer, it is preferable to use a diamine compound (also referred to as a specific diamine compound (4)) represented by the following formula [2d] from the viewpoint of improving afterimage characteristics due to alternating current driving in a liquid crystal display element.

(X represents at least one structure selected from the structures represented by the following formulas [d-1] to [d-8], and A ¹ and A ² each independently represent a hydrogen atom or a carbon number of 1 to 5 represents an alkyl group).

(N represents an integer of 1 to 5).

  Among these, as the specific diamine compound (4), X in the formula [2d] is represented by the formula [d from the viewpoint that the above-described effect, that is, the effect of improving the afterimage characteristics due to AC driving in the liquid crystal display element becomes higher. -1] to formula [d-4], formula [d-6], and diamine compounds represented by formula [d-8] are preferably used. More preferable are the formula [d-1] to the formula [d-3] and the formula [d-8]. Particularly preferred are the formula [d-1] and the formula [d-8].

  The specific diamine compound (4) in the specific polyimide polymer is preferably 50 mol% to 95 mol% in 100 mol% of all diamine components. More preferably, it is 60 mol%-95 mol%. Particularly preferred is 80 mol% to 95 mol%.

  In addition, the specific diamine compound (4) depends on the properties such as the solubility of the specific polyimide polymer in the solvent, the coating property of the liquid crystal alignment treatment agent, and the liquid crystal alignment property and the voltage holding ratio when the liquid crystal alignment film is used. One kind or a mixture of two or more kinds may be used.

  As a diamine component of the specific polyimide polymer, other diamine compounds (also referred to as other diamine compounds) may be used together with the specific diamine compound (1) to the specific diamine compound (4) as long as the effects of the present invention are not impaired. It can also be used.

  Specifically, 2,4-dimethyl-m-phenylenediamine, 2,6-diaminotoluene, m-phenylenediamine, p-phenylenediamine, 4,4′-diaminobiphenyl, 3,3′-dimethyl-4, 4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diamino Biphenyl, 3,3′-difluoro-4,4′-biphenyl, 3,3′-trifluoromethyl-4,4′-diaminobiphenyl, 3,4′-diaminobiphenyl, 3,3′-diaminobiphenyl, 2, , 2′-diaminobiphenyl, 2,3′-diaminobiphenyl, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 3, 4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2 ' -Diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'-sulfonyldianiline, 3,3'-sulfonyldianiline, bis (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl- Bis (4-aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4′-thiodianiline, 3,3′-thiodianiline, 4,4′-diaminodiphenylamine, 3,3′-diaminodiphenylamine, 3,4'-diaminodipheny Amine, 2,2′-diaminodiphenylamine, 2,3′-diaminodiphenylamine, N-methyl (4,4′-diaminodiphenyl) amine, N-methyl (3,3′-diaminodiphenyl) amine, N-methyl ( 3,4′-diaminodiphenyl) amine, N-methyl (2,2′-diaminodiphenyl) amine, N-methyl (2,3′-diaminodiphenyl) amine, 4,4′-diaminobenzophenone, 3,3 ′ -Diaminobenzophenone, 3,4'-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2'-diaminobenzophenone, 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1, , 7-Diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-aminophenyl) ethane, 1,2-bis (3-aminophenyl) ethane, 1, 3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (4-aminophenyl) butane, 1,4-bis (3-aminophenyl) butane, Bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-amino) Phenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (4-aminobenzyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4′- 1,4-phenylenebis (methylene)] dianiline, 4,4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,4 ′-[1,4-phenylenebis (methylene)] dianiline, 3, 4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,3 ′-[1,4-phenylenebis (methylene)] dianiline, 3,3 ′-[1,3-phenylenebis (methylene)] Dianiline, 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [(3-aminophenyl) methanone], 1,4-phenylenebis (4-aminobenzoate), 1,4-phenylenebis (3-amino Zoate), 1,3-phenylenebis (4-aminobenzoate), 1,3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4 -Aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N, N '-(1,4-phenylene) bis (4-aminobenzamide), N, N'-(1,3-phenylene) bis (4-aminobenzamide), N, N ′-(1,4-phenylene) bis (3-aminobenzamide), N, N ′-(1,3-phenylene) bis (3-aminobenzamide), N, N '-Bis (4-aminophenyl) terephthalamide, N, N'-bis (3-aminophenyl) terephthalamide, N, N'-bis (4- Aminophenyl) isophthalamide, N, N′-bis (3-aminophenyl) isophthalamide, 9,10-bis (4-aminophenyl) anthracene, 4,4′-bis (4-aminophenoxy) diphenylsulfone, 2 , 2′-bis [4- (4-aminophenoxy) phenyl] propane, 2,2′-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2′-bis (4-aminophenyl) ) Hexafluoropropane, 2,2′-bis (3-aminophenyl) hexafluoropropane, 2,2′-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2′-bis (4- Aminophenyl) propane, 2,2′-bis (3-aminophenyl) propane, 2,2′-bis (3-amino-4-methylpheny) ) Propane, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3- Aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,6-bis (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- (3-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,8 -Bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10- (4-amino Phenoxy) decane, 1,10- (3-aminophenoxy) decane, 1,11- (4-aminophenoxy) undecane, 1,11- (3-aminophenoxy) undecane, 1,12- (4-aminophenoxy) Dodecane, 1,12- (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane or 1 , 12-diaminododecane, and diamine compounds in which these amino groups are secondary amino groups. It is done.

  Other diamine compounds may be one type or two depending on properties such as solubility of a specific polyimide polymer in a solvent, coating properties of a liquid crystal alignment treatment agent, and liquid crystal alignment properties and voltage holding ratio when used as a liquid crystal alignment film. A mixture of more than one can also be used.

  As the tetracarboxylic acid component for producing the specific polyimide polymer, it is preferable to use a tetracarboxylic dianhydride represented by the following formula [3]. At that time, not only the tetracarboxylic dianhydride represented by the formula [3] but also the tetracarboxylic acid derivative tetracarboxylic acid, tetracarboxylic acid dihalide compound, tetracarboxylic acid dialkyl ester compound or tetracarboxylic acid dialkyl ester di Halide compounds can also be used (tetracarboxylic dianhydrides and derivatives thereof represented by the formula [3] are collectively referred to as a specific tetracarboxylic acid component).

(Z represents at least one structure selected from the following formulas [3a] to [3q]).

Z ^{1 to} Z ⁴ represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring, and may be the same or different.

Z ⁵ and Z ⁶ each represent a hydrogen atom or a methyl group, and may be the same or different.

  Among Z in formula [3], from the viewpoint of easy synthesis and ease of polymerization reactivity when producing a polymer, formula [3a], formula [3c] to formula [3g], formula [3k] ] The tetracarboxylic dianhydride having a structure represented by the formula [3m] or the formula [3p] and its tetracarboxylic acid derivative are preferred. More preferable is the structure represented by the formula [3a], the formula [3e] to the formula [3g], the formula [3l], the formula [3m], or the formula [3p]. Particularly preferred is a tetracarboxylic dianhydride having a structure represented by [3a], formula [3e], formula [3f], formula [3l], formula [3m] or formula [3p] and a tetracarboxylic acid derivative thereof. It is.

  More specifically, it is preferable to use the following formula [3a-1] or formula [3a-2].

  The specific tetracarboxylic acid component in the specific polyimide polymer is preferably 50 mol% to 100 mol% in 100 mol% of all tetracarboxylic acid components. Especially, 70 mol%-100 mol% are preferable. More preferably, it is 80 mol%-100 mol%.

  The specific tetracarboxylic acid component is 1 according to the characteristics such as the solubility of the specific polyimide polymer in the solvent, the coating property of the liquid crystal alignment treatment agent, the liquid crystal alignment property and the voltage holding ratio when the liquid crystal alignment film is used. One kind or a mixture of two or more kinds may be used.

  As long as the effect of this invention is not impaired, other tetracarboxylic acid components other than a specific tetracarboxylic acid component can also be used for a specific polyimide-type polymer.

  Examples of other tetracarboxylic acid components include the following tetracarboxylic acid compounds, tetracarboxylic dianhydrides, tetracarboxylic acid dihalide compounds, tetracarboxylic acid dialkyl ester compounds, and tetracarboxylic acid dialkyl ester dihalide compounds.

  That is, other tetracarboxylic acid components include 1,2,5,6-anthracene tetracarboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4-biphenyltetra Carboxylic acid, bis (3,4-dicarboxyphenyl) ether, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxy) Phenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (3,4-dicarboxyphenyl) propane Bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarbo Acid, 2,6-bis (3,4-dicarboxyphenyl) pyridine, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid and the like. .

  The other tetracarboxylic acid component is 1 according to the characteristics such as the solubility of the specific polyimide polymer in the solvent, the coating property of the liquid crystal alignment treatment agent, the liquid crystal alignment property and the voltage holding ratio when the liquid crystal alignment film is used. One kind or a mixture of two or more kinds may be used.

<Method for producing specific polyimide polymer>
The method for producing the specific polyimide polymer is not particularly limited. Usually, it is obtained by reacting a diamine component and a tetracarboxylic acid component. In general, at least one tetracarboxylic acid component selected from the group consisting of tetracarboxylic dianhydrides and their derivatives is reacted with a diamine component consisting of one or more diamine compounds. And a method of obtaining a polyamic acid. Specifically, a method of obtaining polyamic acid by polycondensation of tetracarboxylic dianhydride and primary or secondary diamine compound, dehydration polycondensation reaction of tetracarboxylic acid and primary or secondary diamine compound A method of obtaining polyamic acid by polycondensation of a tetracarboxylic acid dihalide and a primary or secondary diamine compound is used.

  In order to obtain a polyamic acid alkyl ester, a method of polycondensing a tetracarboxylic acid obtained by dialkyl esterifying a carboxylic acid group with a primary or secondary diamine compound, a tetracarboxylic acid dihalide obtained by dialkyl esterifying a carboxylic acid group, and A method of polycondensation with a primary or secondary diamine compound or a method of converting a carboxyl group of a polyamic acid into an ester is used.

  In order to obtain polyimide, a method is used in which the polyamic acid or polyamic acid alkyl ester is cyclized to form polyimide.

  The reaction between the diamine component and the tetracarboxylic acid component is usually carried out in a solvent with the diamine component and the tetracarboxylic acid component. The solvent used at that time is not particularly limited as long as the produced polyimide precursor is soluble. Although the specific example of the solvent used for reaction below is given, it is not limited to these examples.

  Examples include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide or 1,3-dimethyl-imidazolidinone. It is done. Further, when the solvent solubility of the polyimide precursor is high, it is represented by methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the following formula [D-1] to formula [D-3]. Can be used.

(D ¹ represents an alkyl group having 1 to 3 carbon atoms, D ² represents an alkyl group having 1 to ³ carbon atoms, and D ³ represents an alkyl group having 1 to 4 carbon atoms).

  These solvents may be used alone or in combination. Furthermore, even if it is a solvent which does not dissolve a polyimide precursor, you may mix and use it for the said solvent in the range which the produced | generated polyimide precursor does not precipitate. Moreover, since water in the solvent inhibits the polymerization reaction and further causes hydrolysis of the produced polyimide precursor, it is preferable to use a dehydrated and dried solvent.

  When the diamine component and the tetracarboxylic acid component are reacted in a solvent, the solution in which the diamine component is dispersed or dissolved in the solvent is stirred, and the tetracarboxylic acid component is added as it is or dispersed or dissolved in the solvent. Methods, conversely, a method of adding a diamine component to a solution in which a tetracarboxylic acid component is dispersed or dissolved in a solvent, a method of alternately adding a diamine component and a tetracarboxylic acid component, etc., and any of these methods May be used. In addition, when reacting using a plurality of diamine components or tetracarboxylic acid components, they may be reacted in a premixed state, individually or sequentially, or further individually reacted low molecular weight substances. May be mixed and reacted to form a polymer. Although the polymerization temperature in that case can select the arbitrary temperature of -20 degreeC-150 degreeC, Preferably it is the range of -5 degreeC-100 degreeC. The reaction can be carried out at any concentration, but if the concentration is too low, it is difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution becomes too high and uniform stirring is difficult. It becomes. Therefore, Preferably it is 1 mass%-50 mass%, More preferably, it is 5 mass%-30 mass%. The initial reaction can be carried out at a high concentration, and then a solvent can be added.

  In the polymerization reaction of the polyimide precursor, the ratio of the total number of moles of the diamine component and the total number of moles of the tetracarboxylic acid component is preferably 0.8 to 1.2. Similar to a normal polycondensation reaction, the molecular weight of the polyimide precursor produced increases as the molar ratio approaches 1.0.

  The polyimide is obtained by ring-closing the polyimide precursor. The ring closure rate (also referred to as imidation rate) of the amic acid group is not necessarily 100%, and can be arbitrarily adjusted according to the application and purpose.

  Examples of the method for imidizing the polyimide precursor include thermal imidization in which the polyimide precursor solution is heated as it is or catalyst imidization in which a catalyst is added to the polyimide precursor solution.

  The temperature at which the polyimide precursor is thermally imidized in the solution is 100 ° C. to 400 ° C., preferably 120 ° C. to 250 ° C., and is preferably performed while removing water generated by the imidization reaction from the system.

  The catalyst imidation of the polyimide precursor is performed by adding a basic catalyst and an acid anhydride to the polyimide precursor solution and stirring at -20 ° C to 250 ° C, preferably 0 ° C to 180 ° C. it can. The amount of the basic catalyst is 0.5 to 30 mol times, preferably 2 to 20 mol times of the amic acid group, and the amount of the acid anhydride is 1 to 50 mol times of the amic acid group, Preferably they are 3 mol times-30 mol times. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, pyridine is preferable because it has an appropriate basicity for proceeding with the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. Among them, use of acetic anhydride is preferable because purification after completion of the reaction is facilitated. The imidization rate by catalytic imidation can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

  When recovering the produced polyimide precursor or polyimide from the polyimide precursor or polyimide reaction solution, the reaction solution may be poured into a solvent and precipitated. Examples of the solvent used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polymer precipitated in the solvent can be collected by filtration, and then dried by normal temperature or reduced pressure at room temperature or by heating. Moreover, when the polymer which carried out precipitation collection is re-dissolved in a solvent and the operation which carries out reprecipitation collection is repeated 2-10 times, the impurity in a polymer can be decreased. Examples of the solvent at this time include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more kinds of solvents selected from these because purification efficiency is further increased.

  More specific methods for producing the polyamic acid alkyl ester are shown in the following (1) to (3).

(1) Method of preparing by esterification reaction of polyamic acid Polyamic acid is prepared from a diamine component and a tetracarboxylic acid component, and a chemical reaction, that is, an esterification reaction is performed on the carboxyl group (COOH group). This is a method for producing an alkyl ester.

  Specifically, the esterification reaction is carried out at a temperature of −20 ° C. to 150 ° C. (preferably 0 ° C. to 50 ° C.) for 30 minutes to 24 hours (preferably 1 hour) with a polyamic acid and an esterifying agent in the presence of a solvent. (4 hours).

  As the esterifying agent, those that can be easily removed after the esterification reaction are preferable. N, N-dimethylformamide dimethyl acetal, N, N-dimethylformamide diethyl acetal, N, N-dimethylformamide dipropyl acetal, N, N -Dimethylformamide dineopentyl butyl acetal, N, N-dimethylformamide di-t-butyl acetal, 1-methyl-3-p-tolyltriazene, 1-ethyl-3-p-tolyltriazene, 1-propyl- Examples include 3-p-tolyltriazene and 4- (4,6-dimethoxy-1,3,5-triazin-2-yl) -4-methylmorpholinium chloride. The amount of the esterifying agent used is preferably 2 to 6 molar equivalents per 1 mol of the polyamic acid repeating unit. Of these, 2 molar equivalents to 4 molar equivalents are preferable.

  Examples of the solvent used for the esterification reaction include a solvent used for the reaction of the diamine component and the tetracarboxylic acid component from the viewpoint of solubility of the polyamic acid in the solvent. Of these, N, N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone is preferable. These solvents may be used alone or in combination of two or more.

  The concentration of the polyamic acid in the solvent in the esterification reaction is preferably 1% by mass to 30% by mass from the viewpoint that precipitation of the polyamic acid hardly occurs. Especially, 5 mass%-20 mass% are preferable.

(2) Method of making by reaction of diamine component and tetracarboxylic acid diester dichloride This is a method of making by reaction of diamine component and tetracarboxylic acid diester dichloride.

  Specifically, in this reaction, the diamine component and the tetracarboxylic acid diester dichloride are -30 ° C to 150 ° C (preferably 0 ° C to 50 ° C) in the presence of a base and a solvent for 30 minutes to 24 hours. (Preferably 1 hour to 4 hours) It is the method of making it react.

  As the base, pyridine, triethylamine, 4-dimethylaminopyridine and the like can be used. Of these, pyridine is preferable because the reaction proceeds gently. The amount of the base used is preferably an amount that can be easily removed after the reaction, and is preferably 2 to 4 moles relative to tetracarboxylic acid diester dichloride. Especially, 2 times mole-3 times mole are more preferable.

  Examples of the solvent used for the reaction include a solvent used for the reaction of the diamine component and the tetracarboxylic acid component from the viewpoint of the solubility of the resulting polymer, that is, the polyamic acid alkyl ester, in the solvent. Of these, N, N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone is preferable. These solvents may be used alone or in combination of two or more.

  The concentration of the polyamic acid alkyl ester in the solvent in the reaction is preferably 1% by mass to 30% by mass from the viewpoint that precipitation of the polyamic acid alkyl ester hardly occurs. Especially, 5 mass%-20 mass% are preferable. In order to prevent hydrolysis of the tetracarboxylic acid diester dichloride, it is preferable that the solvent used for preparing the polyamic acid alkyl ester is dehydrated as much as possible. Furthermore, the reaction is preferably performed in a nitrogen atmosphere to prevent outside air from being mixed.

(3) Method of making by reaction of diamine component and tetracarboxylic acid diester It is a method of making by polycondensation reaction of a diamine component and tetracarboxylic acid diester.

  Specifically, in the polycondensation reaction, a diamine component and a tetracarboxylic acid diester are mixed in the presence of a condensing agent, a base and a solvent at 0 ° C. to 150 ° C. (preferably 0 ° C. to 100 ° C.) for 30 minutes to The reaction is performed for 24 hours (preferably 3 to 15 hours).

  Condensation agents include triphenyl phosphite, dicyclohexylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, N, N′-carbonyldiimidazole, dimethoxy-1,3,5-triazinyl Methylmorpholinium, O- (benzotriazol-1-yl) -N, N, N ′, N′-tetramethyluronium tetrafluoroborate, O- (benzotriazol-1-yl) -N, N, N ′, N′-tetramethyluronium hexafluorophosphate, (2,3-dihydro-2-thioxo-3-benzoxazolyl) phosphonate diphenyl, and the like can be used. It is preferable that the usage-amount of a condensing agent is 2 times-3 times mole with respect to tetracarboxylic-acid diester. Especially, 2 times mole-2.5 times mole are preferable.

  As the base, tertiary amines such as pyridine and triethylamine can be used. The amount of the base used is preferably an amount that can be easily removed after the polycondensation reaction, and is preferably 2 to 4 moles relative to the diamine component. Especially, 2 times mole-3 times mole are preferable.

  Examples of the solvent used for the polycondensation reaction include a solvent used for the reaction of the diamine component and the tetracarboxylic acid component from the viewpoint of solubility of the resulting polymer, that is, the polyamic acid alkyl ester, in the solvent. Of these, N, N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone is preferable. These solvents may be used alone or in combination of two or more.

  In the polycondensation reaction, the reaction proceeds efficiently by adding Lewis acid as an additive. As the Lewis acid, lithium halides such as lithium chloride and lithium bromide are preferable. The amount of Lewis acid used is preferably 0.1 to 10 moles relative to the diamine component. Especially, 2.0 times mole-3.0 times mole are more preferable.

  When recovering the polyamic acid alkyl ester from the polyamic acid alkyl ester solution obtained by the methods (1) to (3), the reaction solution may be poured into a solvent and precipitated. Examples of the solvent used for precipitation include water, methanol, ethanol, 2-propanol, hexane, butyl cellosolve, acetone, and toluene. The polymer deposited in the solvent is preferably washed with the solvent several times for the purpose of removing the additives and catalysts used above. After being collected by filtration, it can be dried at normal temperature or under reduced pressure at room temperature or by heating. Moreover, when the polymer which carried out precipitation collection is re-dissolved in a solvent and the operation which carries out reprecipitation collection is repeated 2-10 times, the impurity in a polymer can be decreased. Examples of the solvent at this time include a solvent in which the polymer is dissolved.

  The polyamic acid alkyl ester is preferably produced by the method (1) or (2) among the methods for producing the polyamic acid alkyl ester represented by the above (1) to (3).

<Liquid crystal alignment agent>
The liquid crystal alignment treatment agent in the present invention is a coating solution for forming a liquid crystal alignment film (also referred to as a resin film), and is a coating solution for forming a liquid crystal alignment film containing a specific compound, a specific polyimide polymer, and a solvent. It is a solution.

  The ratio of the specific compound in the liquid crystal aligning agent is preferably 0.1 part by mass to 70 parts by mass with respect to 100 parts by mass of the specific polyimide polymer. Especially, 1 mass part-50 mass parts are preferable, and 1 mass part-30 mass parts are more preferable. Most preferred is 1 to 20 parts by weight.

  All the polymer components in the liquid crystal aligning agent may all be specific polyimide-based polymers, or other polymers may be mixed. Other polymers include specific diamine compounds (1) to specific diamine compounds (4) and polyimide precursors and polyimides that do not use specific tetracarboxylic acid components. Furthermore, a cellulose polymer, an acrylic polymer, a methacrylic polymer, polystyrene, polyamide, or polysiloxane may be used. In that case, it is preferable that content of other polymers other than that is 0.5 mass part-15 mass parts with respect to 100 mass parts of specific polyimide polymers. Especially, 1 mass part-10 mass parts are preferable.

  It is preferable that content of the solvent in the liquid-crystal aligning agent in this invention is 70 mass%-99.9 mass%. This content can be appropriately changed depending on the application method of the liquid crystal aligning agent and the film thickness of the target liquid crystal alignment film.

  The solvent used for the liquid crystal aligning agent is not particularly limited as long as it is a solvent (also referred to as a good solvent) that dissolves the specific compound of the present invention and the specific polyimide polymer. Although the specific example of a good solvent is given to the following, it is not limited to these examples.

  For example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, methyl ethyl ketone , Cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, and the like.

  Of these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and γ-butyrolactone are preferably used.

  Furthermore, when the solubility to the solvent of a specific compound and a specific polyimide-type polymer is high, it is preferable to use the solvent shown by the said formula [D-1]-a formula [D-3].

  The good solvent in the liquid crystal aligning agent is preferably 20% by mass to 99% by mass with respect to the total solvent contained in the liquid crystal aligning agent. Especially, 20 mass%-90 mass% is preferable. More preferably, it is 30% by mass to 80% by mass.

  In the liquid crystal aligning agent in the present invention, unless the effects of the present invention are impaired, a solvent (also referred to as a poor solvent) that improves the coating properties and surface smoothness of the liquid crystal aligning film when the liquid crystal aligning agent is applied. Can be used. Although the specific example of a poor solvent is given to the following, it is not limited to these examples.

  For example, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, isopentyl alcohol, tert-pentyl alcohol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, 1-heptanol 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 1,2- Etanji 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentane Diol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2-hexanone, 2 Heptanone, 4-heptanone, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate 2- (methoxymethoxy) ethanol, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, 2- (hexyloxy) ethanol, furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monobutyl ether, 1- (Butoxyethoxy) propanol, propylene glycol monomethyl ether acetate, dipropylene glycol, Dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoacetate Tar, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2- (2-ethoxyethoxy) ethyl acetate, diethylene glycol acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol Monoethyl ether, milk Methyl, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, 3-methoxypropion Ethyl acid, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, lactic acid Examples thereof include isoamyl esters and solvents represented by the above formulas [D-1] to [D-3].

  Of these, 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate and dipropylene glycol dimethyl ether are preferably used.

  These poor solvents are preferably 1% by mass to 90% by mass of the whole solvent contained in the liquid crystal aligning agent. Especially, 1 mass%-80 mass% are preferable. More preferably, it is 5 mass%-70 mass%.

  In the liquid crystal aligning agent in the present invention, an epoxy group, an isocyanate group, and an oxetane group are crosslinkable having at least one substituent selected from the group consisting of a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group, and a lower alkoxyalkyl group. It is preferable to introduce a compound or a crosslinkable compound having a polymerizable unsaturated bond. It is necessary to have two or more of these substituents and polymerizable unsaturated bonds in the crosslinkable compound.

  Examples of the crosslinkable compound having an epoxy group or an isocyanate group include bisphenolacetone glycidyl ether, phenol novolac epoxy resin, cresol novolac epoxy resin, triglycidyl isocyanurate, tetraglycidylaminodiphenylene, tetraglycidyl-m-xylenediamine, tetra Glycidyl-1,3-bis (aminoethyl) cyclohexane, tetraphenyl glycidyl ether ethane, triphenyl glycidyl ether ethane, bisphenol hexafluoroacetodiglycidyl ether, 1,3-bis (1- (2,3-epoxypropoxy)- 1-trifluoromethyl-2,2,2-trifluoromethyl) benzene, 4,4-bis (2,3-epoxypropoxy) octafluorobiphenyl Triglycidyl-p-aminophenol, tetraglycidylmetaxylenediamine, 2- (4- (2,3-epoxypropoxy) phenyl) -2- (4- (1,1-bis (4- (2,3-epoxy) Propoxy) phenyl) ethyl) phenyl) propane or 1,3-bis (4- (1- (4- (2,3-epoxypropoxy) phenyl) -1- (4- (1- (4- (2,3 -Epoxypropoxy) phenyl) -1-methylethyl) phenyl) ethyl) phenoxy) -2-propanol and the like.

  The crosslinkable compound having an oxetane group is a crosslinkable compound having at least two oxetane groups represented by the following formula [4A].

  Specific examples include crosslinkable compounds represented by formulas [4a] to [4k] described in paragraphs 58 to 59 of International Publication No. WO2011 / 132751 (published 2011.10.27).

  The crosslinkable compound having a cyclocarbonate group is a crosslinkable compound having at least two cyclocarbonate groups represented by the following formula [5A].

  Specifically, the crosslinkable compounds represented by the formulas [5-1] to [5-42] described in the paragraphs 76 to 82 of the international publication WO2012 / 014898 (2012.2.2 publication) can be given. It is done.

  Examples of the crosslinkable compound having at least one substituent selected from the group consisting of a hydroxyl group and an alkoxyl group include an amino resin having a hydroxyl group or an alkoxyl group, such as a melamine resin, a urea resin, a guanamine resin, and a glycoluril. -Formaldehyde resin, succinylamide-formaldehyde resin or ethylene urea-formaldehyde resin. Specifically, a melamine derivative, a benzoguanamine derivative, or glycoluril in which a hydrogen atom of an amino group is substituted with a methylol group or an alkoxymethyl group or both can be used. The melamine derivative or benzoguanamine derivative can exist as a dimer or a trimer. These preferably have an average of 3 to 6 methylol groups or alkoxymethyl groups per triazine ring.

  Examples of such melamine derivatives or benzoguanamine derivatives include MX-750, which has an average of 3.7 substituted methoxymethyl groups per triazine ring, and an average of 5. methoxymethyl groups per triazine ring. Eight-substituted MW-30 (Sanwa Chemical Co., Ltd.) and Cymel 300, 301, 303, 350, 370, 771, 325, 327, 703, 712 and other methoxymethylated melamines, Cymel 235, 236 Methoxymethylated butoxymethylated melamine such as 238, 212, 253, 254, butoxymethylated melamine such as Cymel 506, 508, carboxyl group-containing methoxymethylated isobutoxymethylated melamine such as Cymel 1141, Cymel 1123 and the like Methoxymethylated etoxy Methylated benzoguanamine, methoxymethylated butoxymethylated benzoguanamine such as Cymel 1123-10, butoxymethylated benzoguanamine such as Cymel 1128, carboxyl group-containing methoxymethylated ethoxymethylated benzoguanamine such as Cymel 1125-80 Cyanamide). Examples of glycoluril include butoxymethylated glycoluril such as Cymel 1170, methylolated glycoluril such as Cymel 1172, and methoxymethylolated glycoluril such as Powderlink 1174.

  Examples of the benzene or phenolic compound having a hydroxyl group or an alkoxyl group include 1,3,5-tris (methoxymethyl) benzene, 1,2,4-tris (isopropoxymethyl) benzene, 1,4-bis ( sec-butoxymethyl) benzene or 2,6-dihydroxymethyl-p-tert-butylphenol.

  More specifically, the crosslinkable compounds represented by the formulas [6-1] to [6-48], which are published on pages 62 to 66 of International Publication No. WO2011 / 132751 (published 2011.10.27). Is mentioned.

  Examples of the crosslinkable compound having a polymerizable unsaturated bond include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, and tri (meth) acryloyloxyethoxytrimethylol. Crosslinkable compounds having three polymerizable unsaturated groups in the molecule such as propane or glycerin polyglycidyl ether poly (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (Meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide bisphenol A type di (meth) acrylate, propylene oxide bisphenol type di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin Di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, phthalic acid diglycidyl ester di (meth) acrylate or hydroxypivalic acid neo A crosslinkable compound having two polymerizable unsaturated groups in the molecule, such as pentyl glycol di (meth) acrylate, in addition to 2-hydroxyethyl (meth) acrylate 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 3-chloro It has one polymerizable unsaturated group in the molecule such as 2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl phosphate ester, or N-methylol (meth) acrylamide. Examples thereof include a crosslinkable compound.

  In addition, a compound represented by the following formula [7A] can also be used.

(E ₁ represents a group selected from the group consisting of cyclohexane ring, bicyclohexane ring, benzene ring, biphenyl ring, terphenyl ring, naphthalene ring, fluorene ring, anthracene ring or phenanthrene ring, and E ₂ represents the following formula [ 7a] or a group selected from Formula [7b], and n represents an integer of 1 to 4.

  The said compound is an example of a crosslinkable compound, It is not limited to these. Moreover, the crosslinkable compound used for a liquid-crystal aligning agent may be one type, and may combine two or more types.

  It is preferable that content of a crosslinkable compound in a liquid-crystal aligning agent is 0.1 mass part-150 mass parts with respect to 100 mass parts of all the polymer components. Especially, in order for a crosslinking reaction to advance and to express the target effect, 0.1 mass part-100 mass parts are preferable with respect to 100 mass parts of all the polymer components. More preferred is 1 part by mass to 50 parts by mass.

  As the liquid crystal aligning agent in the present invention, a compound that improves the film thickness uniformity and surface smoothness of the liquid crystal aligning film when the liquid crystal aligning agent is applied can be used as long as the effects of the present invention are not impaired. .

  Examples of the compound that improves the film thickness uniformity and surface smoothness of the liquid crystal alignment film include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants.

  More specifically, for example, F-top EF301, EF303, EF352 (above, manufactured by Tochem Products), MegaFuck F171, F173, R-30 (above, manufactured by Dainippon Ink), Florard FC430, FC431 (or more) Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (above, manufactured by Asahi Glass Co., Ltd.) and the like.

  The use ratio of these surfactants is preferably 0.01 parts by mass to 2 parts by mass, more preferably 0.01 parts by mass with respect to 100 parts by mass of all the polymer components contained in the liquid crystal aligning agent. -1 part by mass.

  Furthermore, in the liquid crystal alignment treatment agent of the present invention, as a compound that promotes charge transfer in the liquid crystal alignment film and promotes charge loss of the element, page 69 of International Publication No. WO2011 / 132751 (published 2011.10.20). It is also possible to add a nitrogen-containing heterocyclic amine compound represented by the formula [M1] to the formula [M156], which is listed on page 73. This amine compound may be added directly to the liquid crystal aligning agent, but it is added after a solution having a concentration of 0.1% by mass to 10% by mass, preferably 1% by mass to 7% by mass with an appropriate solvent. It is preferable. The solvent is not particularly limited as long as it is a solvent that dissolves the specific compound and the specific polyimide polymer described above.

  In the liquid crystal alignment treatment agent in the present invention, in addition to the above poor solvent, crosslinkable compound, resin film or compound that improves the film thickness uniformity and surface smoothness of the liquid crystal alignment film, and a compound that promotes charge removal, As long as the effects of the present invention are not impaired, a dielectric or conductive material for changing the electrical characteristics such as the dielectric constant and conductivity of the liquid crystal alignment film may be added.

<Liquid crystal alignment film and liquid crystal display element>
The liquid crystal alignment film in the present invention is a film obtained by applying the liquid crystal alignment treatment agent to a substrate, drying and baking. The substrate on which the liquid crystal aligning agent is applied is not particularly limited as long as it is a highly transparent substrate, and a plastic substrate such as an acrylic substrate or a polycarbonate substrate can be used together with a glass substrate or a silicon nitride substrate. At that time, it is preferable to use a substrate on which an ITO electrode or the like for driving the liquid crystal is used from the viewpoint of simplification of the process. In the reflective liquid crystal display element, an opaque material such as a silicon wafer can be used as long as it is only on one side of the substrate, and a material that reflects light such as aluminum can be used for the electrode in this case.

  The method for applying the liquid crystal alignment treatment agent is not particularly limited, but industrially, a method of screen printing, offset printing, flexographic printing, an inkjet method, or the like is generally used. Other coating methods include a dipping method, a roll coater method, a slit coater method, a spinner method, and a spray method, and these may be used depending on the purpose.

  After the liquid crystal alignment treatment agent is applied onto the substrate, the solvent can be evaporated by a heating means such as a hot plate, a thermal circulation oven or an IR (infrared) oven to form a liquid crystal alignment film. Arbitrary temperature and time can be selected for the drying and baking process after apply | coating the liquid-crystal aligning agent of this invention. Usually, in order to sufficiently remove the contained solvent, conditions of baking at 50 ° C. to 120 ° C. for 1 minute to 10 minutes and then baking at 150 ° C. to 300 ° C. for 5 minutes to 120 minutes can be mentioned. Although the thickness of the liquid crystal aligning film after baking is not specifically limited, Since the reliability of a liquid crystal display element may fall when too thin, it is preferable that it is 5 nm-300 nm. Among these, 10 nm to 200 nm is preferable.

  Examples of the method for aligning the obtained liquid crystal alignment film include the rubbing method and the photo-alignment method.

  As a specific example of the photo-alignment processing method, the surface of the liquid crystal alignment film is irradiated with radiation deflected in a certain direction, and in some cases, heat treatment is performed at a temperature of 150 ° C. to 250 ° C. A liquid crystal alignment ability). As the radiation, ultraviolet rays or visible rays having a wavelength of 100 nm to 800 nm can be used. Among these, ultraviolet rays having a wavelength of 100 nm to 400 nm are preferable, and ultraviolet rays having a wavelength of 200 nm to 400 nm are more preferable.

Moreover, in order to improve liquid crystal orientation, you may irradiate a radiation, heating the board | substrate with which the liquid crystal aligning film was coated at 50 to 250 degreeC. The irradiation amount of the ^{radiation, 1mJ / cm 2 ~10,000mJ / cm} 2 is preferred. Among ^{them, 100mJ / cm 2 ~5,000mJ / cm} 2 is preferred. The liquid crystal alignment film thus prepared can stably align liquid crystal molecules in a certain direction.

  Further, the liquid crystal alignment film irradiated with polarized radiation can be subjected to contact treatment using water or a solvent by the above method. The solvent used for the contact treatment is not particularly limited as long as it is a solvent that dissolves a decomposition product generated from the liquid crystal alignment film by irradiation with radiation. 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, 3- Examples thereof include methyl methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate or cyclohexyl acetate. Of these, water, 2-propanol, 1-methoxy-2-propanol or ethyl lactate is preferable from the viewpoint of versatility and solvent safety. More preferred is water, 1-methoxy-2-propanol or ethyl lactate. These solvents may be used alone or in combination of two or more.

  Examples of the contact treatment, that is, treatment of water or a solvent on the liquid crystal alignment film irradiated with polarized radiation include immersion treatment and spray treatment (also referred to as spray treatment). The treatment time in these treatments is preferably 10 seconds to 1 hour from the viewpoint of efficiently dissolving the decomposition products generated from the liquid crystal alignment film by radiation. Especially, it is preferable to immerse for 1 minute-30 minutes. Moreover, although the solvent at the time of the said contact process may be heated at normal temperature, Preferably it is 10 to 80 degreeC. Especially, 20 to 50 degreeC is preferable. In addition, from the viewpoint of the solubility of the decomposition product, ultrasonic treatment or the like may be performed as necessary.

  After the contact treatment, it is preferable to perform rinsing (also referred to as rinsing) with a low-boiling solvent such as water, methanol, ethanol, 2-propanol, acetone, or methyl ethyl ketone, and baking of the liquid crystal alignment film. At that time, either rinsing or firing may be performed, or both may be performed. The firing temperature is preferably 150 ° C to 300 ° C. Especially, 180 to 250 degreeC is preferable. More preferably, it is 200 degreeC-230 degreeC. The firing time is preferably 10 seconds to 30 minutes. Especially, 1 minute-10 minutes are preferable.

  The liquid crystal alignment film in the present invention is suitable as a liquid crystal alignment film of a horizontal electric field type liquid crystal display element such as an IPS (In-Plane Switching) driving method or a fringe field switching (also referred to as FFS) method. It is useful as a liquid crystal alignment film of a liquid crystal display element.

  The liquid crystal display element in the present invention is a liquid crystal cell produced by a known method after obtaining a substrate with a liquid crystal alignment film obtained from a liquid crystal alignment treatment agent as in the production method described above. It is a liquid crystal display element.

  As an example of a method for manufacturing a liquid crystal cell, a liquid crystal display element having a passive matrix structure will be described as an example. Note that an active matrix liquid crystal display element in which a switching element such as a TFT (Thin Film Transistor) is provided in each pixel portion constituting the image display may be used.

Specifically, a transparent glass substrate is prepared, a common electrode is provided on one substrate, and a segment electrode is provided on the other substrate. These electrodes can be ITO electrodes, for example, and are patterned so as to display a desired image. Next, an insulating film is provided on each substrate so as to cover the common electrode and the segment electrode. The insulating film can be, for example, a film made of SiO ₂ —TiO ₂ formed by a sol-gel method. Next, under the conditions as described above, a liquid crystal alignment film is formed on each substrate, the other substrate is overlapped with one substrate so that the liquid crystal alignment film faces each other, and the periphery is sealed with a sealant. Glue. In order to control the substrate gap, a spacer is usually mixed in the sealant. In addition, it is preferable that spacers for controlling the substrate gap are also sprayed on the in-plane portion where no sealant is provided. A part of the sealant is provided with an opening that can be filled with liquid crystal from the outside.

  Thereafter, a liquid crystal material is injected into a space surrounded by the two substrates and the sealant through an opening provided in the sealant. Thereafter, the opening is sealed with an adhesive. For the injection, a vacuum injection method may be used, or a method utilizing capillary action in the atmosphere may be used. As the liquid crystal material, either a positive liquid crystal material or a negative liquid crystal material may be used. Next, a polarizing plate is installed. Specifically, a pair of polarizing plates is attached to the surfaces of the two substrates opposite to the liquid crystal layer.

  When the liquid crystal aligning agent of this invention is used, the liquid crystal aligning film which can suppress peeling of the liquid crystal aligning film accompanying the physical impact with respect to a liquid crystal display element, or generation | occurrence | production of a foreign material is obtained. Furthermore, a liquid crystal alignment film that can enhance the adhesion between the liquid crystal alignment film and the sealant and increase the strength of the liquid crystal display element can be obtained. In particular, it is useful for a liquid crystal alignment film for photo-alignment treatment obtained by irradiating polarized radiation. Therefore, the liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the present invention has excellent reliability, and is suitable for a large-screen high-definition liquid crystal television, a small and medium-sized smartphone, a tablet terminal, and the like. Can be used.

  The present invention will be described in more detail with reference to the following examples, but is not limited thereto.

"Abbreviations used in the synthesis examples, examples and comparative examples of the present invention"
Abbreviations used in the synthesis examples, examples and comparative examples are as follows.
<Monomer for producing polyimide polymer>
(Specific diamine compound (1))
A1: Diamine compound of the following formula [A1]

(Specific diamine compound (2))
B1: Diamine compound of the following formula [B1]

(Specific diamine compound (3))
C1: Diamine compound of the following formula [C1]

(Specific diamine compound (4))
D1: p-phenylenediamine D2: Diamine compound of the following formula [D2]

(Other diamine compounds)
E1: 3,5-Diaminobenzoic acid E2: Diamine compound of the following formula [E2]

(Specific tetracarboxylic acid component)
F1: 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride F2: 1,2,3,4-cyclobutanetetracarboxylic dianhydride F3: 3,3 ′, 4,4 '-Biphenyltetracarboxylic dianhydride F4: tetracarboxylic acid dialkyl ester dihalide compound of the following formula [F4] F5: 1,2,3,4-butanetetracarboxylic dianhydride F6: pyromellitic dianhydride

<Specific compounds>
The symbols and structural formulas of the specific compounds used are shown below.

<Other compounds>
Z1: Compound of the following formula [Z1]

<Solvent>
NMP: N-methyl-2-pyrrolidone NEP: N-ethyl-2-pyrrolidone γ-BL: γ-butyrolactone BCS: ethylene glycol monobutyl ether PB: propylene glycol monobutyl ether

"Measurement of molecular weight of polyimide polymer"
The molecular weight of the polyimide precursor and polyimide is as follows using a normal temperature gel permeation chromatography (GPC) apparatus (GPC-101) (Showa Denko) and columns (KD-803, KD-805) (Shodex). It measured as follows.

Column temperature: 50 ° C
Eluent: N, N′-dimethylformamide (as additives, lithium bromide-hydrate (LiBr · H ₂ O) is 30 mmol / L (liter), phosphoric acid / anhydrous crystal (o-phosphoric acid) is 30 mmol / L, 10 ml / L of tetrahydrofuran (THF))
Flow rate: 1.0 ml / min Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight; about 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight; about 12,000, 4,000 and 1,000) (manufactured by Polymer Laboratory).

"Measurement of imidization ratio of polyimide"
The imidation ratio of polyimide was measured as follows. 20 mg of polyimide powder was put into an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube standard, φ5 (manufactured by Kusano Kagaku)), and deuterated dimethyl sulfoxide (DMSO-d6, 0.05 mass% TMS (tetramethylsilane)). (Mixed product) (0.53 ml) was added and completely dissolved by applying ultrasonic waves. This solution was measured for proton NMR at 500 MHz with an NMR measuring instrument (JNW-ECA500) (manufactured by JEOL Datum). The imidation rate is determined based on protons derived from structures that do not change before and after imidation as reference protons, and the peak integrated value of these protons and proton peaks derived from NH groups of amic acid appearing in the vicinity of 9.5 ppm to 10.0 ppm. It calculated | required by the following formula | equation using the integrated value.

  Imidation ratio (%) = (1−α · x / y) × 100

  In the formula, x is a proton peak integrated value derived from the NH group of amic acid, y is a peak integrated value of a reference proton, and α is one NH group proton of amic acid in the case of polyamic acid (imidation rate is 0%). The number ratio of the reference protons.

"Synthesis of polyimide polymers"
<Synthesis Example 1>
F2 (3.92 g, 20.0 mmol) is added to a 100 mL four-necked flask equipped with a stirrer and a nitrogen introducing tube, NMP (55.8 g) is added thereto, and D1 (2. 09 g, 19.3 mmol) was added, and NMP was further added so that the solid concentration was 10% by mass, followed by stirring at 25 ° C. for 4 hours to obtain a polyamic acid solution (1). The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 300 mPa · s. The number average molecular weight of this polyamic acid was 11,000, and the weight average molecular weight was 23,200.

<Synthesis Example 2>
E2 (6.15 g, 31.0 mmol) and NMP (70.7 g) were added to a 100 ml four-necked flask equipped with a stirrer and a nitrogen introduction tube, and stirred and dissolved while feeding nitrogen. While stirring this diamine solution, NMP was added so that F1 (6.94 g, 31.0 mmol) and the solid content concentration were 10% by mass, and the mixture was stirred at 25 ° C. for 4 hours to obtain a polyamic acid solution (2). It was. This polyamic acid solution had a viscosity at 25 ° C. of 300 mPa · s. The number average molecular weight of this polyamic acid was 12,000, and the weight average molecular weight was 25,200.

<Synthesis Example 3>
D1 (2.92 g, 27.0 mmol) and A1 (0.71 g, 2.99 mmol) are taken to a 100 mL four-necked flask equipped with a stirrer and a nitrogen introduction tube, NMP (81.8 g) is added, The solution was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, F1 (6.46 g, 28.8 mmol) was added, NMP was further added so that the solid content concentration was 10% by mass, and the mixture was stirred for 4 hours at 25 ° C. (3) was obtained. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 230 mPa · s. The number average molecular weight of this polyamic acid was 11,100, and the weight average molecular weight was 30,000.

<Synthesis Example 4>
C1 (7.68 g, 36.0 mmol) and E1 (0.61 g, 4.01 mmol) were taken into a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, and NMP (24.0 g) and γ-BL were taken. (6.00 g) was added and dissolved by stirring while feeding nitrogen. While stirring this diamine solution, F5 (6.34 g, 32.0 mmol) and γ-BL (12.0 g) were added, and the mixture was stirred at 25 ° C. for 2 hours. Thereafter, F6 (1.74 g, 7.98 mmol) and γ-BL were added so that the solid content concentration was 10% by mass, and the mixture was stirred at 25 ° C. for 4 hours to obtain a polyamic acid solution (4). The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 460 mPa · s. The number average molecular weight of this polyamic acid was 12,000, and the weight average molecular weight was 24,000.

<Synthesis Example 5>
B1 (5.97 g, 20.0 mmol) was added to a 100 mL four-necked flask equipped with a stirrer and a nitrogen introduction tube, NMP (75.9 g) was added, and the mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, F3 (5.53 g, 18.8 mmol) was added, NMP was further added so that the solid content concentration was 10% by mass, and the mixture was stirred at 25 ° C. for 4 hours to obtain a polyamic acid solution ( 5) was obtained. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 400 mPa · s. The number average molecular weight of this polyamic acid was 11,500, and the weight average molecular weight was 24,400.

<Synthesis Example 6>
A 500 mL four-necked flask equipped with a stirrer is placed in a nitrogen atmosphere, D1 (2.80 g, 25.9 mmol) is taken, A1 (1.45 g, 6.11 mmol) is added, NMP (111 g) and pyridine (6. 18 g) was added and dissolved by stirring. Next, while stirring this diamine solution, F4 (9.89 g, 30.4 mmol) was added and reacted at 15 ° C. for 15 hours. Thereafter, acryloyl chloride (0.38 g) was added and reacted at 15 ° C. for 4 hours. The obtained polyamic acid alkyl ester solution was poured into water (1230 g) with stirring, and the precipitated white precipitate was collected by filtration, washed 5 times with IPA (isopropyl alcohol) (1230 g), and dried. White polyamic acid alkyl ester powder (10.2 g) was obtained. The number average molecular weight of this polyamic acid alkyl ester was 20,800, and the weight average molecular weight was 41,000.

  The obtained polyamic acid alkyl ester powder (0.80 g) is placed in a 100 mL Erlenmeyer flask, γ-BL (7.18 g) is added, and the mixture is stirred and dissolved at 25 ° C. for 24 hours. A polyamic acid alkyl ester solution (6) was obtained.

<Synthesis Example 7>
In a 100 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, take A1 (0.47 g, 1.98 mmol) and D2 (4.40 g, 18.0 mmol), add NMP (59.5 g), The solution was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, F1 (4.15 g, 18.5 mmol) was added, NMP was further added so that the solid content concentration was 10% by mass, and the polyamic acid solution was stirred by stirring at 25 ° C. for 4 hours. Obtained.

  To the obtained polyamic acid solution (66.0 g), NEP was added and diluted to 9% by mass. Then, acetic anhydride (5.38 g) and pyridine (1.39 g) were added as imidization catalysts, and the mixture was heated at 60 ° C. for 3 hours. Reacted. This reaction solution was poured into methanol (360 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 60 degreeC, and obtained the polyimide powder (7). The imidation ratio of this polyimide was 75%, the number average molecular weight was 10,100, and the weight average molecular weight was 20,500.

<Synthesis Example 8>
D1 (2.16 g, 20.0 mmol) was added to a 100 mL four-necked flask equipped with a stirrer and a nitrogen introduction tube, NMP (31.6 g) was added, and the mixture was stirred and dissolved while feeding nitrogen. While stirring this diamine solution, F1 (4.21 g, 18.8 mmol) was added, NMP was further added so that the solid content concentration was 10% by mass, and the mixture was stirred at 25 ° C. for 4 hours to obtain a polyamic acid solution ( 8) was obtained. The viscosity of this polyamic acid solution at a temperature of 25 ° C. was 250 mPa · s. The number average molecular weight of this polyamic acid was 11,500, and the weight average molecular weight was 24,400.

  Table 2 shows the polyimide polymers of the present invention.

* 1: Polyamic acid * 2: Polyamic acid alkyl ester

“Production of Liquid Crystal Alignment Treatment Agent of the Present Invention”
In Examples 1 to 18 and Comparative Examples 1 to 4, production examples of liquid crystal alignment treatment agents are described.

  The liquid crystal aligning agents obtained in the examples and comparative examples are shown in Tables 3 to 5.

  Using the liquid crystal alignment treatment agents obtained in the examples and comparative examples, “Evaluation of resistance to rubbing treatment (evaluation on peeling of liquid crystal alignment film and generation of foreign matters due to physical impact)”, “Sealant and base substrate Evaluation of adhesion (Evaluation of adhesion between liquid crystal alignment film and sealant) "," Evaluation of inkjet coating property of liquid crystal alignment treatment agent "," Evaluation of afterimage by AC drive (FFS type liquid crystal cell) "and" Evaluation of charge relaxation characteristics (FFS type liquid crystal cell) "was performed.

"Evaluation of resistance to rubbing treatment (Evaluation on peeling of liquid crystal alignment film and generation of foreign matter due to physical impact)"
With an ITO (Indium Tin Oxide) transparent electrode, the liquid crystal alignment treatment agents obtained in Examples and Comparative Examples were filtered under pressure through a membrane filter having a pore size of 1.0 μm and washed with pure water and IPA (isopropyl alcohol). It spin-coats on the ITO surface of a glass substrate (length 40 mm x width 30 mm, thickness 0.7 mm), and heat-treats on a hot plate at 80 ° C for 5 minutes and in a heat-circulating clean oven at 250 ° C for 60 minutes. Thus, a substrate with an ITO transparent electrode with a liquid crystal alignment film having a film thickness of 100 nm was obtained.

  Then, when the liquid crystal aligning agent obtained in Example 1, Example 7, Example 8, Comparative Example 1 and Comparative Example 2 was used, rubbing treatment was performed. Specifically, the liquid crystal alignment film surface of the substrate with the ITO transparent electrode produced under the above conditions is a rubbing treatment apparatus having a roll diameter of 120 mm, using a rayon cloth, roll rotation speed: 1000 rpm, roll progress speed: The test was performed under the conditions of 20 mm / sec and pushing amount: 0.3 mm.

Moreover, when the liquid crystal aligning agent obtained by the Example and comparative example other than the above was used, the photo-alignment process was performed. Specifically, the conditions were such that the liquid crystal alignment film surface of the substrate with an ITO transparent electrode produced under the above conditions was irradiated with UV light of 254 nm through a polarizing plate at 600 mJ / cm ² .

  The rubbing treatment was performed on the substrate with the ITO transparent electrode with the liquid crystal alignment film subjected to the rubbing treatment and the photo-alignment treatment. Specifically, the liquid crystal alignment film surface of the substrate with the ITO transparent electrode subjected to these treatments was subjected to a rubbing treatment apparatus having a roll diameter of 120 mm, using a rayon cloth, and a roll rotation speed: 500 rpm, a roll traveling speed: The measurement was performed under the conditions of 20 mm / sec and pushing amount: 0.6 mm.

  The surface state of the obtained liquid crystal alignment film was observed using a confocal laser microscope. Specifically, the surface of the liquid crystal alignment film in the vicinity of the center of the substrate is randomly observed with a confocal laser microscope set at a magnification of 100 times, and is confirmed within an observation visual field of about 6.5 mm square. The rubbing treatment resistance was evaluated from the average value of rubbing scratches and rubbing scraps (adhered matter). The evaluation criteria were determined as follows.

(Evaluation criteria)
A: 20 or fewer scratches or scraps B: 21 to 39 scratches or scraps C: 40 or more scraps or scraps

  Note that the closer the evaluation criteria are to A, that is, the fewer rubbing scratches and rubbing scraps, the better the rubbing resistance (the evaluation criteria are shown in Tables 6 to 8).

  Tables 6 to 8 show the results obtained in Examples and Comparative Examples.

"Evaluation of adhesion between sealant and base substrate (Evaluation on adhesion between liquid crystal alignment film and sealant)"
With an ITO (Indium Tin Oxide) transparent electrode, the liquid crystal alignment treatment agents obtained in Examples and Comparative Examples were filtered under pressure through a membrane filter having a pore size of 1.0 μm and washed with pure water and IPA (isopropyl alcohol). It spin-coats on the ITO surface of a glass substrate (length 40 mm x width 30 mm, thickness 0.7 mm), and heat-treats on a hot plate at 80 ° C for 5 minutes and in a heat-circulating clean oven at 250 ° C for 60 minutes. Thus, a substrate with an ITO transparent electrode with a liquid crystal alignment film having a film thickness of 100 nm was obtained.

  Then, when the liquid crystal aligning agent obtained in Example 1, Example 7, Example 8, Comparative Example 1 and Comparative Example 2 was used, rubbing treatment was performed. Specifically, the liquid crystal alignment film surface of the substrate with the ITO transparent electrode produced under the above conditions is a rubbing treatment apparatus having a roll diameter of 120 mm, using a rayon cloth, roll rotation speed: 1000 rpm, roll progress speed: The test was performed under the conditions of 20 mm / sec and pushing amount: 0.3 mm.

Moreover, when the liquid crystal aligning agent obtained by the Example and comparative example other than the above was used, the photo-alignment process was performed. Specifically, the conditions were such that the liquid crystal alignment film surface of the substrate with an ITO transparent electrode produced under the above conditions was irradiated with UV light of 254 nm through a polarizing plate at 600 mJ / cm ² .

  Regarding the substrate with the ITO transparent electrode with the liquid crystal alignment film subjected to the rubbing process and the photo-alignment process, two substrates subjected to the same process are prepared, and a 6 μm bead spacer is provided on the liquid crystal alignment film surface of one of the substrates. Was further applied to the liquid crystal alignment film surface of the other substrate by printing. Thereafter, these substrates were bonded so that the overlapping width of the substrates was 1 cm. At that time, the amount of the sealing agent was adjusted so that the diameter of the sealing agent region after bonding was 3 mm. Further, the two bonded substrates were fixed with a clip, and then heat-treated at 150 ° C. for 1 hour in a heat circulation type clean oven to obtain a test cell (FIG. 1 shows the structure of the test cell). Show). This test cell was stored for 72 hours in a high-temperature and high-humidity tank having a temperature of 60 ° C. and a humidity of 90% to obtain a test cell for this evaluation.

  The obtained test cell for this evaluation was pushed in from the upper part of the center of the substrate after fixing the end portions of the upper and lower substrates with a desktop precision universal testing machine (AGS-X 500N) (manufactured by Shimadzu Corporation). The pressure (N) at the time of peeling, that is, the peeling pressure (N) was measured.

  In the evaluation, the larger the value of the peel stress (N), the better the adhesion with the sealing agent and the base substrate (Tables 6 to 8 show the values of the peel stress (N)).

  Tables 6 to 8 show the results obtained in Examples and Comparative Examples.

"Evaluation of inkjet coating properties of liquid crystal alignment treatment agents"
The liquid crystal aligning agent (3) obtained in Example 3 was pressure filtered through a membrane filter having a pore size of 1 μm, and HIS-200 (manufactured by Hitachi Plant Technology Co., Ltd.) was used as an ink jet coating machine. On the ITO (Indium Tin Oxide) vapor-deposited substrate cleaned in step 1, the coating area is 70 x 70 mm, the nozzle pitch is 0.423 mm, the scan pitch is 0.5 mm, the coating speed is 40 mm / second, from coating to temporary drying For 60 seconds, temporary drying was performed on a hot plate at 80 ° C. for 5 minutes, and main firing was performed in a heat-circulating clean oven at 250 ° C. for 60 minutes.

  When the obtained substrate with a liquid crystal alignment film was visually observed under a sodium lamp and the number of pinholes on the liquid crystal alignment film was counted, the number of pinholes was less than 5. Moreover, the liquid crystal aligning film excellent in the coating-film uniformity was obtained.

  Furthermore, by using the obtained substrate with a liquid crystal alignment film, the above-mentioned “evaluation of rubbing treatment resistance (evaluation on peeling of liquid crystal alignment film and generation of foreign matters due to physical impact)”, “sealing agent and base substrate and "Evaluation of adhesion between liquid crystal alignment film and sealant", "Evaluation of afterimage by AC drive (FFS type liquid crystal cell)" and "Evaluation of charge relaxation characteristics (FFS type liquid crystal cell)" Was done.

"Evaluation of afterimage by liquid crystal display element driven by alternating current (FFS type liquid crystal cell)"
After filtering the liquid crystal aligning agent obtained in Example 2, Example 4 to Example 6 and Example 10 through a 1.0 μm filter, the film thickness of 50 nm is formed as an electrode on the first layer on the glass substrate. The second electrode is made of silicon nitride having a thickness of 500 nm as an insulating film, and the third layer is made of a comb-like ITO electrode as an electrode (electrode width: 3 μm, electrode interval: 6 μm, electrode height) : A liquid crystal alignment treatment agent was applied to a glass substrate on which an FFS driving electrode having 50 nm) was formed by spin coating. Then, after drying on an 80 degreeC hotplate for 5 minutes, it baked for 60 minutes in 250 degreeC hot-air circulation type oven, and formed the coating film with a film thickness of 100 nm. The coating surface was irradiated with UV light of 254 nm at 600 mJ / cm ² through a polarizing plate to obtain a substrate with a liquid crystal alignment film. Further, a coating film was similarly formed on a glass substrate having a columnar spacer having a height of 4 μm on which no electrode was formed as a counter substrate, and an orientation treatment was performed.

  Regarding the substrate with the ITO transparent electrode with the liquid crystal alignment film that has been subjected to the photo-alignment treatment, two substrates that have been subjected to the same treatment are prepared, and the two substrates are combined into one set, and a sealant is printed on the substrate. Then, another substrate was bonded so that the liquid crystal alignment film faces each other and the alignment direction was 0 °, and then the sealing agent was cured to produce an empty cell. Liquid crystal MLC-2041 (manufactured by Merck Japan Ltd.) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS liquid crystal cell.

  Using this FFS liquid crystal cell, an AC voltage of ± 10 V was applied for 120 hours at a frequency of 60 Hz in a constant temperature environment of 60 ° C. Thereafter, the pixel electrode and the counter electrode of the liquid crystal cell were short-circuited and left as it was at room temperature for one day.

  After standing, the liquid crystal cell is placed between two polarizing plates arranged so that the polarization axes are orthogonal to each other, and the backlight is turned on with no voltage applied, so that the liquid crystal has the lowest brightness. The cell placement angle was adjusted. Then, the rotation angle when the liquid crystal cell was rotated from the angle at which the second region of the first pixel became darkest to the angle at which the first region became darkest was calculated as an angle Δ (°). Similarly, in the second pixel, the second region and the first region were compared, and a similar angle Δ (°) was calculated. And the average value of angle (DELTA) (degree) of a 1st pixel and a 2nd pixel was computed as angle (DELTA) (degree) of a liquid crystal cell. In this evaluation, the smaller the value of the liquid crystal cell angle Δ (°), the better (the value of the liquid crystal cell angle Δ (°) is shown in Table 6).

  Table 6 shows the results obtained in the examples.

"Charge relaxation characteristics of liquid crystal display devices (FFS type liquid crystal cells)"
After the liquid crystal aligning agent obtained in Example 1, Example 2, Example 4 to Example 8 and Example 10 was filtered through a 1.0 μm filter, the first layer was used as an electrode on the glass substrate. A shaped ITO electrode with a thickness of 50 nm, an insulating film as a second layer with a silicon nitride shape with a thickness of 500 nm, and a third layer as an electrode with a comb-like ITO electrode (electrode width: 3 μm, electrode spacing: A liquid crystal alignment treatment agent was applied by spin coating to a glass substrate on which an FFS driving electrode having 6 μm and an electrode height of 50 nm was formed. Then, after drying on an 80 degreeC hotplate for 5 minutes, it baked for 60 minutes in 250 degreeC hot-air circulation type oven, and formed the coating film with a film thickness of 100 nm.

  Then, when the liquid crystal aligning agent obtained in Example 1, Example 7, and Example 8 was used, the rubbing process was performed. Specifically, the liquid crystal alignment film surface of the substrate with the ITO transparent electrode produced under the above conditions is a rubbing treatment apparatus having a roll diameter of 120 mm, using a rayon cloth, roll rotation speed: 1000 rpm, roll progress speed: The test was performed under the conditions of 20 mm / sec and pushing amount: 0.3 mm.

Moreover, when the liquid crystal aligning agent obtained by the Example and comparative example other than the above was used, the photo-alignment process was performed. Specifically, the conditions were such that the liquid crystal alignment film surface of the substrate with an ITO transparent electrode produced under the above conditions was irradiated with UV light of 254 nm through a polarizing plate at 600 mJ / cm ² .

  Regarding the substrate with the ITO transparent electrode with the liquid crystal alignment film that has been subjected to the rubbing treatment and the photo-alignment treatment, two substrates that have been subjected to the same treatment are prepared, and the two substrates are combined into a set and sealed on the substrate. The adhesive was printed, and another substrate was bonded so that the liquid crystal alignment film faced and the alignment direction was 0 °, and then the sealing agent was cured to produce an empty cell. Liquid crystal MLC-2041 (manufactured by Merck Japan Ltd.) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS liquid crystal cell.

  This FFS mode liquid crystal cell is placed on a light source, and after measuring VT characteristics (voltage-transmittance characteristics) at a temperature of 25 ° C., a liquid crystal cell in a state where a rectangular wave of ± 3 V / 120 Hz is applied The transmittance (Ta) was measured. Thereafter, a rectangular wave of ± 3 V / 120 Hz was applied for 10 minutes at a temperature of 25 ° C., and then driving was performed for 60 minutes with 2 V DC superimposed. The transmittance (Tb) of the liquid crystal cell when the DC voltage is cut and the AC drive is performed for 60 minutes is measured, and the transmission caused by the voltage remaining in the liquid crystal display element from the difference (ΔT) in the initial transmittance (Ta) The difference in rate was calculated. In this evaluation, the smaller the transmittance difference (ΔT), the better (the value of transmittance difference (ΔT) is shown in Table 6).

  Table 6 shows the results obtained in the examples.

<Example 1>
NMP (4.75 g), BCS (3.44 g) and X3 (0.10 g) were added to the polyamic acid solution (1) (10.0 g) obtained by the synthesis method of Synthesis Example 1, and the mixture was added at 25 ° C. It stirred for 1 hour and obtained the liquid-crystal aligning agent (1). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (1), “rubbing treatment resistance evaluation (evaluation regarding peeling of liquid crystal alignment film and generation of foreign matters due to physical impact)”, “adhesion between sealing agent and base substrate” (Evaluation of adhesion between liquid crystal alignment film and sealing agent) "and" Evaluation of charge relaxation characteristics (FFS type liquid crystal cell) ".

<Example 2>
NMP (4.75 g), BCS (3.44 g), and X3 (0.10 g) are added to the polyamic acid solution (2) (10.0 g) obtained by the synthesis method of Synthesis Example 2, and then at 25 ° C. The mixture was stirred for 1 hour to obtain a liquid crystal aligning agent (2). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (2), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film and generation of foreign matter due to physical impact)”, “adhesion with sealant and base substrate” "Evaluation of adhesion (evaluation of adhesion between liquid crystal alignment film and sealant)", "Evaluation of afterimage by AC drive (FFS type liquid crystal cell)" and "Evaluation of charge relaxation characteristic (FFS type liquid crystal cell)" went.

<Example 3>
Polyamide acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4 and polyamic acid alkyl ester solution (6) (3.30 g) obtained by the synthesis method of Synthesis Example 6 were added to NMP (1 .20 g), γ-BL (12.7 g), PB (5.34 g) and X3 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (3). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (3), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film and generation of foreign matter due to physical impact)” and “adhesion with sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 4>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X3 (0.083 g) were added and stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (4). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (4), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)”, “adhesion with sealing agent and base substrate” "Evaluation of adhesiveness (Evaluation of adhesion between liquid crystal alignment film and sealant)", "Evaluation of afterimage by AC drive (FFS type liquid crystal cell)" and "Evaluation of charge relaxation characteristic (FFS type liquid crystal cell)" went.

<Example 5>
NMP (3.35 g) was added to the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4 and the polyamic acid solution (8) (3.30 g) obtained by the synthesis method of Synthesis Example 8. ), Γ-BL (0.56 g), BCS (2.84 g) and X3 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (5). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (5), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal aligning film due to physical impact and generation of foreign matter)”, “adhesion with sealing agent and base substrate” "Evaluation of adhesiveness (Evaluation of adhesion between liquid crystal alignment film and sealant)", "Evaluation of afterimage by AC drive (FFS type liquid crystal cell)" and "Evaluation of charge relaxation characteristic (FFS type liquid crystal cell)" went.

<Example 6>
NMP (3.35 g) was added to the polyamic acid solution (2) (3.30 g) obtained by the synthesis method of Synthesis Example 2 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X3 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (6). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (6), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film and generation of foreign matters due to physical impact)”, “adhesion with sealing agent and base substrate” "Evaluation of adhesiveness (Evaluation of adhesion between liquid crystal alignment film and sealant)", "Evaluation of afterimage by AC drive (FFS type liquid crystal cell)" and "Evaluation of charge relaxation characteristic (FFS type liquid crystal cell)" went.

<Example 7>
To the polyamic acid solution (4) (10.0 g) obtained by the synthesis method of Synthesis Example 4, NMP (3.90 g), γ-BL (0.87 g), BCS (3.44 g) and X3 (0. 10 g) was added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (7). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (7), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)”, “adhesion with sealant and base substrate” (Evaluation of adhesion between liquid crystal alignment film and sealing agent) "and" Evaluation of charge relaxation characteristics (FFS type liquid crystal cell) ".

<Example 8>
NMP (4.75 g), BCS (3.44 g) and X3 (0.10 g) were added to the polyamic acid solution (5) (10.0 g) obtained by the synthesis method of Synthesis Example 5, and the mixture was added at 25 ° C. It stirred for 1 hour and obtained the liquid-crystal aligning agent (8). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (8), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)”, “adhesion with sealant and base substrate” (Evaluation of adhesion between liquid crystal alignment film and sealing agent) "and" Evaluation of charge relaxation characteristics (FFS type liquid crystal cell) ".

<Example 9>
NMP (5.00 g), γ-BL (2.74 g) and NEP (5.15 g) are added to the polyimide powder (7) (0.80 g) obtained by the synthesis method of Synthesis Example 7, and the mixture is heated to 70 ° C. And stirred for 24 hours to dissolve. Thereafter, the polyamic acid solution (4) (4.00 g), BCS (4.12 g) and X3 (0.12 g) were added to this solution, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal alignment treatment agent (9 ) This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (9), "rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)" and "adhesion with sealant and base substrate" Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 10>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X3 (0.16 g) were added and stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (10). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (10), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film and generation of foreign matters due to physical impact)”, “adhesion with sealant and base substrate” "Evaluation of adhesion (evaluation of adhesion between liquid crystal alignment film and sealant)", "Evaluation of afterimage by AC drive (FFS type liquid crystal cell)" and "Evaluation of charge relaxation characteristic (FFS type liquid crystal cell)" went.

<Example 11>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X3 (0.029 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (11). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (11), “rubbing process resistance evaluation (evaluation regarding peeling of liquid crystal aligning film due to physical impact and generation of foreign matter)” and “adhesion with sealing agent and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 12>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X1 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (12). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (12), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film and generation of foreign matter due to physical impact)” and “adhesion between sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 13>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X2 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (13). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (13), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film and generation of foreign matters due to physical impact)” and “adhesion between sealing agent and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 14>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X4 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (14). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (14), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)” and “adhesion with sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 15>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X5 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (15). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (15), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal aligning film due to physical impact and generation of foreign matter)” and “adhesion with sealing agent and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 16>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X6 (0.083 g) were added and stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (16). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (16), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)” and “adhesion with sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 17>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X7 (0.083 g) were added and stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (17). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (17), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)” and “adhesion with sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Example 18>
NMP (3.35 g) was added to the polyamic acid solution (3) (3.30 g) obtained by the synthesis method of Synthesis Example 3 and the polyamic acid solution (4) (4.95 g) obtained by the synthesis method of Synthesis Example 4. ), Γ-BL (0.56 g), BCS (2.84 g) and X8 (0.083 g) were added, and the mixture was stirred at 25 ° C. for 1 hour to obtain a liquid crystal aligning agent (18). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (18), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film and generation of foreign matters due to physical impact)” and “adhesion between sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Comparative Example 1>
NMP (4.75 g) and BCS (3.44 g) were added to the polyamic acid solution (1) (10.0 g) obtained by the synthesis method of Synthesis Example 1, and the mixture was stirred for 1 hour at 25 ° C. An alignment agent (19) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (19), "rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)" and "adhesion with sealant and base substrate" Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Comparative example 2>
NMP (4.75 g) and BCS (3.44 g) were added to the polyamic acid solution (2) (10.0 g) obtained by the synthesis method of Synthesis Example 2, and the mixture was stirred for 1 hour at 25 ° C. An alignment agent (20) was obtained. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (20), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)” and “adhesion with sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Comparative Example 3>
NMP (4.75 g), BCS (3.44 g) and Z1 (0.10 g) were added to the polyamic acid solution (1) (10.0 g) obtained by the synthesis method of Synthesis Example 1, and the mixture was added at 25 ° C. The liquid crystal aligning agent (21) was obtained by stirring for 1 hour. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal alignment treatment agent (21), “rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal alignment film due to physical impact and generation of foreign matter)” and “adhesion with sealant and base substrate” Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

<Comparative example 4>
NMP (4.75 g), BCS (3.44 g) and Z1 (0.10 g) were added to the polyamic acid solution (2) (10.0 g) obtained by the synthesis method of Synthesis Example 2, and the mixture was added at 25 ° C. The liquid crystal aligning agent (22) was obtained by stirring for 1 hour. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (22), "rubbing treatment resistance evaluation (evaluation on peeling of liquid crystal aligning film due to physical impact and generation of foreign matter)" and "adhesion with sealant and base substrate" Evaluation (Evaluation on Adhesiveness between Liquid Crystal Alignment Film and Sealing Agent) ”.

* 1: The introduction amount of each polymer (polyimide polymer) with respect to 100 parts by mass of all polymers (polyimide polymer) indicates (parts by mass).
* 2: Indicates the amount (parts by mass) of the specific compound introduced relative to 100 parts by mass of all polymers (polyimide polymers).
* 3: Indicates the introduction amount (parts by mass) of each solvent with respect to 100 parts by mass of all the solvents.
* 4: Indicates the proportion (% by mass) of all the polymers (polyimide polymer) in the liquid crystal alignment treatment agent.

* 1: The introduction amount of each polymer (polyimide polymer) with respect to 100 parts by mass of all polymers (polyimide polymer) indicates (parts by mass).
* 2: Indicates the amount (parts by mass) of the specific compound introduced relative to 100 parts by mass of all polymers (polyimide polymers).
* 3: Indicates the introduction amount (parts by mass) of each solvent with respect to 100 parts by mass of all the solvents.
* 4: Indicates the proportion (% by mass) of all the polymers (polyimide polymer) in the liquid crystal alignment treatment agent.

* 1: The introduction amount of each polymer (polyimide polymer) with respect to 100 parts by mass of all polymers (polyimide polymer) indicates (parts by mass).
* 2: An introduction amount (parts by mass) of other compounds with respect to 100 parts by mass of all polymers (polyimide polymers).
* 3: Indicates the introduction amount (parts by mass) of each solvent with respect to 100 parts by mass of all the solvents.
* 4: Indicates the proportion (% by mass) of all the polymers (polyimide polymer) in the liquid crystal alignment treatment agent.

  From the comparison between Example 1 and Comparative Example 1 and the comparison between Example 2 and Comparative Example 2, the liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the present invention was obtained from the liquid crystal alignment treatment agent of Comparative Example. Compared to the obtained liquid crystal alignment film, the result was excellent in resistance to rubbing treatment and adhesion to the sealing agent and the base substrate. In particular, with respect to the adhesiveness with the sealing agent and the base substrate, even when stored under high temperature and high humidity conditions, results of excellent adhesiveness with these were obtained.

  Moreover, the liquid crystal aligning film obtained from the liquid-crystal aligning agent of this invention using the specific compound from the comparison with Example 1 and the comparative example 3 and the comparison with Example 2 and the comparative example 4 is other compounds. Compared with the liquid crystal aligning film obtained from the liquid crystal aligning agent using this, it became the result excellent in the rubbing process tolerance and the adhesiveness with a sealing agent and a base substrate.

  Moreover, from the comparison between Example 4 and Examples 12 to 18, when the specific compound represented by the formula [X3] was used, the adhesion with the sealing agent and the base substrate was further improved.

  The liquid crystal aligning agent of the present invention comprising a specific compound having a specific structure and at least one polymer selected from a polyimide precursor and a polyimide is a liquid crystal alignment film peeling or foreign matter due to a physical impact on the liquid crystal display element. It is possible to obtain a liquid crystal alignment film that can suppress the occurrence of the above. Furthermore, the liquid crystal alignment film which can improve the adhesiveness of a liquid crystal aligning film and a sealing agent and can make the intensity | strength of a liquid crystal display element high can be obtained. In particular, it is useful for a liquid crystal alignment film for photo-alignment treatment obtained by irradiating polarized radiation. Therefore, the liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the present invention has excellent reliability, and is suitable for a large-screen high-definition liquid crystal television, a small and medium-sized smartphone, a tablet terminal, and the like. Can be used.

Claims (21)

Liquid crystal aligning agent containing the following (A) component and (B) component.
(A) Component: Compound represented by Formula [1].

(W ¹ represents an organic group having 1 to 30 carbon atoms, and W ² represents —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CON (CH ₃ ) —, _{-N (CH 3) CO -,} - COO -, - OCO- and represents at least one linking group selected from -S-, n is an integer of 1-6).
(B) component: At least 1 type of polymer chosen from a polyimide precursor and a polyimide. The liquid crystal aligning agent according to claim 1, wherein W ¹ in the formula [1] has at least one structure selected from the following formulas [1a] and [1b].

(W ³ and W ⁵ each independently represent a benzene ring or a cyclohexane ring, and W ⁴ represents a single bond, —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, At least one linking group selected from —CON (CH ₃ ) —, —N (CH ₃ ) CO—, —COO—, —OCO—, and —S—, q represents an integer of 0 to 4; In the formula [1b], W ⁶ represents an alkylene group having 1 to 10 carbon atoms, an alkenylene group having 1 to 10 carbon atoms, or an alkynylene group having 1 to 10 carbon atoms, and hydrogen bonded to any of these carbon atoms The atom may be replaced by a halogen-containing alkyl group, a halogen atom, a hydroxyl group (OH group), or a carboxyl group (COOH group), and * represents a bond with W ² . The liquid crystal aligning agent according to claim 2, wherein the compound of the component (A) is at least one compound selected from the following formulas [1-1] to [1-8].

(B) A polyimide precursor obtained by using a diamine component containing at least one diamine compound selected from diamine compounds represented by the following formulas [2a-1] to [2a-3]: The liquid-crystal aligning agent of any one of Claims 1-3 which is at least 1 sort (s) of polymer chosen from a polyimide and a polyimide.

(X ¹ , X ³ and X ⁷ , and X ⁸ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, -O-, -N (R ¹ )-(R ¹ is a hydrogen atom or carbon indicates the number 1-3 alkyl ^{group), - CON (R 2)} - (R 2 represents a hydrogen atom or an alkyl group having 1 to 3 carbon ^{atoms), - N (R 3)} CO- (R 3 is hydrogen Represents an atom or an alkyl group having 1 to 3 carbon atoms), represents at least one organic group selected from —CH ₂ O—, —COO— and —OCO—, and represents X ² , X ⁴ and X ⁶ , and X ⁹ each independently represents a single bond or an alkylene group having 1 to 10 carbon atoms, X ^a and X ^e each independently represent a hydrogen atom or an organic group having 1 to 20 carbon atoms, and X ^b , X ^{e c} and X ^f are each independently a protecting group to replace a hydrogen atom by heat, Represents an integer of 1 or 2, p represents an integer of 1 to 4, q is an integer of 1 to 4, ^{X 5} represents a single bond or an alkylene group having 1 to 10 carbon atoms, r is 1 4 represents an integer, X ^d represents a single bond or an organic group having 1 to 20 carbon atoms, n represents an integer of 1 to 4, s represents an integer of 1 to 4, and t represents an integer of 1 to 4. A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms). In the diamine compounds represented by the formulas [2a-1] to [2a-3], X ^b , X ^c and X ^f are each independently represented by the following formulas [a-1] to [a-6]. The liquid-crystal aligning agent of Claim 4 which is a diamine compound which is a protecting group which has a structure shown by these.

(R ¹ represents an alkyl group having 1 to 5 carbon atoms). The liquid crystal alignment according to claim 4, wherein the diamine compound represented by the formula [2a-1] to the formula [2a-3] is a diamine compound represented by the following formula [2a-4] to the formula [2a-12]. Processing agent.

(R ^{1 to} R ¹⁴ each independently represents at least one structure selected from the structures represented by the formulas [a-1] to [a-6], and A ^{1 to} A ¹⁸ are each independently selected. A hydrogen atom or an alkyl group having 1 to 5 carbon atoms). The polymer of the said (B) component is at least 1 sort (s) of polymer chosen from the polyimide precursor and polyimide which are obtained using the diamine component containing the diamine compound shown by following formula [2b]. The liquid crystal aligning agent of any one of Claim 6.

(Y ¹ and Y ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —S—, —N (R ¹ ) — (R ¹ is a hydrogen atom or 1 to 3 represents an alkyl group), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom or carbon) Represents an alkyl group having a number of 1 to 3, and represents at least one organic group selected from —CH ₂ O—, —COO—, and —OCO—, and Y ² and Y ⁶ each independently represent carbon number 1 -10 represents an alkylene group, Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, Y ⁴ represents an oxygen atom or a sulfur atom, and A ¹ and A ² represent Each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms). The liquid crystal aligning agent according to claim 7, wherein the diamine compound represented by the formula [2b] is a diamine compound represented by the following formulas [2b-1] to [2b-3].

(A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms). The polyimide precursor obtained by using the diamine component in which the polymer of the component (B) contains at least one diamine compound selected from diamine compounds represented by the following formulas [2c-1] to [2c-3] The liquid-crystal aligning agent of any one of Claims 1-8 which is at least 1 sort (s) of polymer chosen from a body and a polyimide.

(X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring, X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms, and X ² represents a hydrogen atom. In the case, X ¹ represents a nitrogen-containing aromatic heterocyclic ring, and when X ² is a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms, X ¹ represents a benzene ring, and X ³ and X ⁷ Each independently represents an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings, and X ⁴ and X ⁶ each independently represent a hydrogen atom or 1 to 5 carbon atoms. X ⁵ represents an alkylene group having 2 to ⁵ carbon atoms or a biphenyl group, m represents an integer of 0 or 1, and X ⁸ and X ¹⁰ each independently represent the following formula [c-1 ] and represents at least one structure selected from the formula [c-2], X Represents an alkylene group or a benzene ring having 1 to 5 carbon atoms, A ¹ to A ⁶ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

The liquid crystal alignment according to claim 9, wherein the diamine compound represented by the formula [2c-1] to the formula [2c-3] is a diamine compound represented by the following formula [2c-4] to the formula [2c-7]. Processing agent.

(R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, n in Formula [2c-7] represents an integer of 1 to 10, and A ^{1 to} A ⁸ each independently represents a hydrogen atom or An alkyl group having 1 to 5 carbon atoms). The polymer of the said (B) component is at least 1 sort (s) of polymer chosen from the polyimide precursor and polyimide which are obtained using the diamine component containing the diamine compound shown by following formula [2d]. The liquid-crystal aligning agent of any one of Claims 10.

(X represents at least one structure selected from the following formulas [d-1] to [d-8], and A ¹ and A ² each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Show).

(N represents an integer of 1 to 5). The polymer of the component (B) is at least one polymer selected from a polyimide precursor and a polyimide obtained using a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula [3] The liquid-crystal aligning agent of any one of Claims 1-11 which is these.

(Z represents at least one structure selected from the following formulas [3a] to [3q]).

(Z ^{1 to} Z ⁴ represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring, and may be the same or different, and in the formula [3g], Z ⁵ and Z ⁶ are A hydrogen atom or a methyl group, which may be the same or different. The tetracarboxylic acid component has a structure in which Z in the formula [3] is represented by the formula [3a], the formula [3e] to the formula [3g], the formula [3l], the formula [3m], or the formula [3p]. The liquid crystal aligning agent according to claim 12, which is a tetracarboxylic acid component having at least one structure selected from the group consisting of: The liquid crystal alignment according to any one of claims 1 to 13, wherein the compound of the component (A) is 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the polymer of the component (B). Processing agent. The liquid crystal aligning agent according to any one of claims 1 to 14, wherein the polymer of the component (B) is a polyamic acid alkyl ester. 16. The solvent according to claim 1, comprising at least one solvent selected from N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and γ-butyrolactone as a solvent for the liquid crystal alignment treatment agent. Liquid crystal aligning agent as described in. As a solvent for the liquid crystal aligning agent, from 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate and dipropylene glycol dimethyl ether The liquid-crystal aligning agent of any one of Claims 1-16 containing the at least 1 sort (s) of solvent chosen. The liquid crystal aligning film obtained from the liquid-crystal aligning agent of any one of Claims 1-17. The liquid crystal aligning film obtained by the inkjet method using the liquid-crystal aligning agent of any one of Claims 1-17. A liquid crystal alignment film obtained by irradiating the liquid crystal alignment film according to claim 18 or 19 with polarized radiation. The liquid crystal display element which has a liquid crystal aligning film of any one of Claims 18-20.

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