WO2016076412A1

WO2016076412A1 - Liquid crystal alignment treatment agent, liquid crystal alignment film, and liquid crystal display element

Info

Publication number: WO2016076412A1
Application number: PCT/JP2015/081947
Authority: WO
Inventors: 橋本　淳; 暁子若林; 徳俊三木; 保坂　和義; 直樹中家
Original assignee: 日産化学工業株式会社
Priority date: 2014-11-13
Filing date: 2015-11-13
Publication date: 2016-05-19
Also published as: KR20170085488A; CN107003567A; JP6683955B2; JPWO2016076412A1; KR102512108B1; TW201632572A; CN107003567B; TWI588190B

Abstract

Disclosed is a liquid crystal alignment treatment agent comprising the following components (A) and (B), wherein the component (A) is a heteropoly acid, and the component (B) is a polymer.

Description

Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element

The present invention relates to a liquid crystal alignment treatment agent used in the production of 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.

As liquid crystal display elements are becoming higher in definition, a liquid crystal alignment film used in the liquid crystal alignment film is required to have a high voltage holding ratio from the viewpoint of suppressing a decrease in contrast of the liquid crystal display element and reducing an afterimage phenomenon. On the other hand, in addition to polyamic acid and its imidized polymer, etc., a compound containing one carboxylic acid group in the molecule, a compound containing one carboxylic anhydride group in the molecule, and the molecule One using a liquid crystal aligning agent containing a very small amount of a compound selected from compounds containing one tertiary amino group is known (see, for example, Patent Document 1).

In addition, as liquid crystal display elements have become higher definition, there is a demand for reduction in contrast of liquid crystal display elements and suppression of display defects associated with long-term use. For these, in liquid crystal alignment films using polyimide, liquid crystal using liquid crystal alignment treatment agent added with alkoxysilane compound as a technique to enhance liquid crystal alignment and make display defects less likely to occur at the periphery of the liquid crystal display screen An alignment film has been proposed (see, for example, Patent Document 2 or Patent Document 3).

JP-A-8-76128 Japanese Patent Laid-Open No. 61-171762 JP 11-119226 A

With the recent improvement in performance of liquid crystal display elements, liquid crystal display elements are used for large-screen, high-definition liquid crystal televisions and in-vehicle applications such as car navigation systems and meter panels. In such applications, in order to obtain high luminance, a backlight with a large calorific value may be used. For this reason, the liquid crystal alignment film is required to have high reliability from another point of view, that is, high stability to light from the backlight. In particular, when the voltage holding ratio, which is one of the electrical characteristics of the liquid crystal display element, is reduced by light irradiation from the backlight, a burn-in defect (also called line burn-in), which is one of the display defects of the liquid crystal display element. As a result, the liquid crystal display element with high reliability cannot be obtained. Therefore, in the liquid crystal alignment film, in addition to good initial characteristics, for example, it is required that the voltage holding ratio does not easily decrease even after being exposed to light irradiation for a long time.

Also, in mobile applications such as smartphones and mobile phones, the usage environment is becoming harsher than before. That is, in addition to the conventional room temperature and low humidity environment, it may be used under high temperature and high humidity. When used under such high temperature and high humidity conditions, water tends to be mixed from between the sealant of the liquid crystal display element and the liquid crystal alignment film, and display unevenness is likely to occur near the frame of the liquid crystal display element. is there. Therefore, it is required that such display defects do not occur even under high temperature and high humidity conditions.

Therefore, an object of the present invention is to provide a liquid crystal alignment film having the above characteristics. That is, an object of the present invention is to provide a liquid crystal alignment film that can suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time. In addition, an object is to provide a liquid crystal alignment film in which display unevenness does not occur in the vicinity of the frame of the liquid crystal display element even under high temperature and high humidity conditions.

In addition, another object is to provide a liquid crystal display device having the liquid crystal alignment film, a liquid crystal alignment treatment agent that can provide the liquid crystal alignment film, and a composition used for the liquid crystal alignment treatment agent.

As a result of diligent research, the present inventors have found that a liquid crystal aligning agent containing a compound having a specific structure and a polymer is extremely effective for achieving the above object, and has completed the present invention. It was.

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

(2) The liquid crystal alignment treatment according to the above (1), wherein the heteropolyacid is at least one selected from the group consisting of phosphomolybdic acid, silicomolybdic acid, phosphotungstic acid, silicotungstic acid, and phosphotungstomolybdic acid. Agent.

(3) The liquid crystal aligning agent according to (1) or (2), wherein the polymer has a nitrogen-containing aromatic heterocycle.

(4) The above (1), wherein the polymer is at least one selected from the group consisting of acrylic polymer, methacrylic polymer, novolak resin, polyhydroxystyrene, polyimide precursor, polyimide, polyamide, polyester, cellulose and polysiloxane. The liquid crystal aligning agent according to any one of (3) above.

(5) The liquid-crystal aligning agent as described in said (4) whose said polymer is the polyimide which imidized the polyimide precursor obtained by reaction of a diamine component and a tetracarboxylic acid component, or this polyimide precursor.

(6) The liquid-crystal aligning agent as described in said (5) in which the said diamine component contains the diamine compound which has a structure shown by following formula [2].

(W ¹ is —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —OCO—, —CON (CH ₃ ) — and —N (CH ₃ ) At least one linking group selected from the group consisting of CO—, wherein W ² is at least one selected from the group consisting of a single bond, an alkylene group having 1 to 20 carbon atoms, a non-aromatic ring and an aromatic ring. W ³ represents a single bond, —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —COO—, —OCO—, —CON (CH ₃ ) —, At least one selected from the group consisting of —N (CH ₃ ) CO— and —O (CH ₂ ) _m — (m represents an integer of 1 to 5), W ⁴ represents a nitrogen-containing aromatic heterocyclic ring; Show.)

(7) The liquid-crystal aligning agent as described in said (6) in which the said diamine component contains the diamine compound shown by following formula [2a].

(W represents the structure represented by the formula [2]. M1 represents an integer of 1 to 4.)

(8) The liquid crystal alignment according to any one of (5) to (7), wherein the diamine component includes a diamine compound having a structure represented by the following formula [3-1] or [3-2]: Processing agent.

(Y ¹ is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —CONH—, —NHCO—, —CON (CH ₃ ) —, —N (CH ₃ ) CO—, —COO—, and —OCO— represent at least one linking group selected from the group consisting of Y ² is a single bond or — (CH ₂ ) _b — (b is 1 Y ³ is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— and —. Y ⁴ represents at least one selected from the group consisting of OCO—, wherein Y ⁴ has at least one divalent cyclic group selected from the group consisting of a benzene ring, a cyclohexane ring and a heterocyclic ring, or a carbon number of 17 to 17 having a steroid skeleton. 51 represents a divalent organic group, and an arbitrary hydrogen atom on the cyclic group has 1 carbon atom. 3 alkyl group, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, good .Y ⁵ be substituted with a fluorine-containing alkoxyl group or a fluorine atom having 1 to 3 carbon atoms benzene At least one cyclic group selected from the group consisting of a ring, a cyclohexane ring and a heterocyclic ring, wherein any hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms or an alkoxyl having 1 to 3 carbon atoms Group, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom, n represents an integer of 0 to 4. Y ⁶ represents 1 carbon atom. An alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, and a fluorine-containing alkoxyl group having 1 to 18 carbon atoms. At least one selected from the group of

(Y ⁷ is a single bond, —O—, —CH ₂ O—, —CONH—, —NHCO—, —CON (CH ₃ ) —, —N (CH ₃ ) CO—, —COO— and —OCO—. And at least one linking group selected from the group consisting of Y ⁸ represents an alkyl group having 8 to 18 carbon atoms or a fluorine-containing alkyl group having 6 to 18 carbon atoms.)

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

(Y represents the structure represented by Formula [3-1] or Formula [3-2]. N1 represents an integer of 1 to 4.)

(10) The liquid crystal aligning agent according to any one of (5) to (9), wherein the tetracarboxylic acid component contains a tetracarboxylic dianhydride represented by the following formula [4].

(Z represents at least one structure selected from the group consisting of structures represented by the following formulas [4a] to [4k].)

(Z ¹ to Z ⁴ each independently represents at least one selected from the group consisting of a hydrogen atom, a methyl group, a chlorine atom and a benzene ring. Z ⁵ and Z ⁶ each independently represent a hydrogen atom or methyl Group.)

(11) The liquid crystal aligning agent contains at least one solvent selected from the group consisting of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and γ-butyrolactone. 10) The liquid-crystal aligning agent in any one of.

(12) The liquid crystal alignment treatment agent is 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, dipropylene glycol dimethyl ether and the following formula [ D1] to the liquid crystal aligning agent according to any one of (1) to (11) above, which contains at least one solvent selected from the group consisting of solvents represented by formula [D3].

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

(13) The liquid crystal aligning agent comprises a crosslinkable compound selected from the group consisting of an epoxy group, an isocyanate group, an oxetane group and a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group, and an alkoxyalkyl group having 1 to 3 carbon atoms. The liquid crystal aligning agent according to any one of (1) to (12) above, which contains a crosslinkable compound selected from the group or a crosslinkable compound having a polymerizable unsaturated bond group.

(14) A liquid crystal alignment film obtained from the liquid crystal alignment treatment agent according to any one of (1) to (13). *

(15) A liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to any one of (1) to (13) above by an inkjet method.

(16) A liquid crystal display device having the liquid crystal alignment film according to (14) or (15).

(17) A liquid crystal composition having a liquid crystal layer between a pair of substrates provided with electrodes and including a polymerizable compound that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates. The liquid crystal alignment film according to (14) or (15), wherein the liquid crystal alignment film is used for a liquid crystal display device produced through a step of polymerizing the polymerizable compound while applying a voltage between the electrodes.

(18) A liquid crystal display device comprising the liquid crystal alignment film according to (17).

(19) A liquid crystal alignment film comprising a liquid crystal layer between a pair of substrates provided with electrodes and including a polymerizable group that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates. The liquid crystal alignment film according to (14) or (15), wherein the liquid crystal alignment film is used for a liquid crystal display device produced through a step of polymerizing the polymerizable group while applying a voltage between the electrodes.

(20) A liquid crystal display element comprising the liquid crystal alignment film according to (19).

The liquid crystal alignment treatment agent containing the specific compound and polymer of the present invention can provide a liquid crystal alignment film capable of suppressing a decrease in voltage holding ratio even after being exposed to light irradiation for a long time. In addition, a liquid crystal alignment film in which display unevenness does not occur near the frame of the liquid crystal display element even under high temperature and high humidity conditions. *

The reason why the liquid crystal display device having the above-described excellent characteristics is obtained by the present invention is not necessarily clear, but is estimated as follows.

The present invention relates to 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 further a liquid crystal display element having the liquid crystal aligning film. Is.
Component (A): heteropolyacid (also referred to as a specific compound).
Component (B): a polymer.

The following are possible effects of the specific compound. One of the factors that decrease the voltage holding ratio is that there are many ionic impurity components in the liquid crystal. On the other hand, when the liquid crystal display element is exposed to light irradiation for a long time and the liquid crystal is decomposed, the ionic impurity component generated at that time is adsorbed by the specific compound, and the voltage holding ratio is lowered. It is thought to suppress. Moreover, when the polymer which has a nitrogen-containing aromatic heterocyclic ring is used, it is thought that this heterocyclic ring can raise the effect more.

Further, a polyimide precursor obtained by the reaction of a diamine component and a tetracarboxylic acid component or a polyimide obtained by imidizing the polyimide precursor is used as a polymer, and the diamine component at that time is represented by the formula [3-1] or Using a diamine compound having a structure represented by the formula [3-2], a liquid crystal alignment treatment agent for a liquid crystal display element in a vertical (VA: Vertical Alignment) mode, a PSA (Polymer Sustained Alignment) mode, and an SC-PVA mode In particular, since the structure represented by the formula [3-1] shows a rigid structure, a liquid crystal display element using a liquid crystal alignment film having this structure is stable to light such as ultraviolet rays. Generation of ionic impurities that lower the voltage holding ratio can be suppressed.

Thus, the liquid crystal display element provided with the liquid crystal alignment film obtained from the liquid crystal aligning agent in the present invention has excellent reliability and can be suitably used for a large-screen, high-definition liquid crystal television. In particular, it is useful for a liquid crystal display element using a PSA mode or an SC-PVA mode that irradiates high-energy ultraviolet rays when manufacturing a liquid crystal display element.

<Specific compounds>
The specific compound in the present invention is a heteropolyacid.

The heteropolyacid is typically a heteroatom located at the center of a molecule represented by the Keggin type represented by the following formula [1-1] or the Dawson type chemical structure represented by the formula [1-2]. It is a polyacid obtained by condensing an isopolyacid that is an oxygen acid such as vanadium (V), molybdenum (Mo), or tungsten (W) with an oxygen acid of a different element. Examples of the oxygen acid of such a different element mainly include silicon (Si), phosphorus (P), and arsenic (As) oxygen acids.

Specific examples of the heteropolyacid compound include phosphomolybdic acid, silicomolybdic acid, phosphotungstic acid, silicotungstic acid, and phosphotungstomolybdic acid, and these are preferably used in the present invention. Moreover, these may be used independently and may be used in combination of 2 or more types. In addition, the heteropolyacid compound in this invention is available as a commercial item, and can also be synthesize | combined by a well-known method.

Heteropoly acids can be obtained as commercial products in the quantitative analysis such as elemental analysis, even if the number of elements is large or small from the structure represented by the general formula, or appropriately synthesized according to known synthesis methods. As long as it is, it can be used in the present invention.

That is, for example, generally, phosphotungstic acid has a structure represented by the following formula [1a], and phosphomolybdic acid has a structure represented by the formula [1b].

These are available as commercial products in quantitative analysis even if P (phosphorus), O (oxygen), or W (tungsten) or Mo (molybdenum) in these formulas are large or small. As long as it is synthesized or appropriately synthesized according to a known synthesis method, it can be used in the present invention. In this case, the mass of the heteropolyacid defined in the present invention is not the mass of pure phosphotungstic acid (phosphotungstic acid content) in the synthesized product or commercially available product, but is a commercially available form and a known synthesis. In a form that can be isolated by the method, it means the total mass in a state containing hydration water and other impurities.

<Polymer>
The polymer in the present invention may be at least one polymer selected from the group consisting of acrylic polymer, methacrylic polymer, novolak resin, polyhydroxystyrene, polyimide precursor, polyimide, polyamide, polyester, cellulose and polysiloxane. preferable. More preferred are polyimide precursors, polyimides or polysiloxanes. Particularly preferred are polyimide precursors and polyimides (also collectively referred to as specific polyimide polymers).

In addition, as described above, for the purpose of further enhancing the effects of the present invention, it is preferable that these polymers contain a nitrogen-containing aromatic heterocycle.

The nitrogen-containing aromatic heterocycle is a heterocycle containing a structure represented by the following formula [a], formula [b] or formula [c].

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

More specifically, pyrrole ring, imidazole ring, oxazole ring, thiazole ring, pyrazole ring, pyridine ring, pyrimidine ring, quinoline ring, pyrazoline ring, isoquinoline ring, carbazole ring, purine ring, thiadiazole ring, pyridazine ring, pyrazoline ring , Triazine ring, pyrazolidine ring, triazole ring, pyrazine ring, benzimidazole ring, benzimidazole ring, cinnoline ring, phenanthroline ring, indole ring, quinoxaline ring, benzothiazole ring, phenothiazine ring, oxadiazole ring and acridine ring be able to. Among these, a pyrrole ring, an imidazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a triazine ring, a triazole ring, a pyrazine ring, a benzimidazole ring, or a benzimidazole ring is preferable. More preferred are a pyrrole ring, an imidazole ring, a pyrazole ring, a pyridine ring or a pyrimidine ring from the viewpoint that a decrease in voltage holding ratio after being exposed to light irradiation for a long time can be suppressed. Particularly preferred is an imidazole ring or a pyridine ring.

<Specific polyimide polymer>
When using a specific polyimide polymer for the polymer of the present invention, they are preferably a polyimide precursor or a polyimide obtained by reacting a diamine component and a tetracarboxylic acid component.

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

(R ¹ represents a tetravalent organic group. R ² represents a divalent organic group. A ¹ and A ² each independently represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms. A ³ And A ⁴ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or an acetyl group, and nA represents a positive integer.

Examples of the diamine component include diamines 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.

The specific polyimide polymer can be obtained relatively easily by using a tetracarboxylic dianhydride represented by the following formula [B] and a diamine represented by the following formula [C] as raw materials. Polyamic acid composed of a structural formula of a repeating unit represented by the following formula [D] or polyimide obtained by imidizing the polyamic acid is preferable. Especially, in this invention, it is preferable that it is the polyimide which imidated the polyimide precursor from the point of the physical and chemical stability of a liquid crystal aligning film.

(R ¹ and R ² have the same meaning as defined in formula [A].)

(R ¹ , R ² and nA have the same meaning as defined in formula [A].)

In addition, the polymer of the formula [D] obtained above by the usual synthesis method is added to the alkyl group having 1 to 8 carbon atoms of A ¹ and A ^{2 represented by} the formula [A] and the formula [A]. It is also possible to introduce an alkyl group having 1 to 5 carbon atoms or an acetyl group of A ³ and A ⁴ shown.

A well-known thing can be used as a diamine component in this invention.

Among them, as described above, for the purpose of further enhancing the effect of the present invention, it is preferable to use a diamine compound having a structure represented by the following formula [2] (also referred to as a specific structure (1)).

In the formula [2], W ¹ , W ² , W ³ and W ⁴ are as defined above, and among them, the following are preferable.

W ¹ is preferably —O—, —NH—, —CONH—, —NHCO—, —CH ₂ O—, —OCO—, —CON (CH ₃ ) — or —N (CH ₃ ) CO—. More preferred is —O—, —NH—, —CONH—, —NHCO—, —CH ₂ O—, —OCO— or —CON (CH ₃ ) — from the viewpoint of ease of synthesis. Particularly preferred is —O—, —CONH— or —CH ₂ O—.

W ² represents at least one selected from the group consisting of a single bond, an alkylene group having 1 to 20 carbon atoms, a non-aromatic ring and an aromatic ring.

The alkylene group having 1 to 20 carbon atoms may be linear or branched. Moreover, you may have an unsaturated bond. Among these, an alkylene group having 1 to 10 carbon atoms is preferable from the viewpoint of ease of synthesis.

Specific examples of the non-aromatic ring include a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, a cyclononane ring, a cyclodecane ring, a cycloundecane ring, a cyclododecane ring, and a cyclotridecane ring. , Cyclotetradecane ring, cyclopentadecane ring, cyclohexadecane ring, cycloheptadecane ring, cyclooctadecane ring, cyclononadecane ring, cycloicosane ring, tricycloeicosan ring, tricyclodecosan ring, bicycloheptane ring, decahydronaphthalene ring, norbornene And a ring and an adamantane ring. Among these, a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a norbornene ring, or an adamantane ring is preferable.

Specific examples of the aromatic ring include a benzene ring, a naphthalene ring, a tetrahydronaphthalene ring, an azulene ring, an indene ring, a fluorene ring, an anthracene ring, a phenanthrene ring and a phenalene ring. Of these, a benzene ring, naphthalene ring, tetrahydronaphthalene ring, fluorene ring or anthracene ring is preferred.

W ² includes a single bond, an alkylene group having 1 to 10 carbon atoms, a cyclopropane ring, a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, a cycloheptane ring, a norbornene ring, an adamantane ring, a benzene ring, a naphthalene ring, and a tetrahydronaphthalene ring , A fluorene ring or an anthracene ring is preferred. Among these, a single bond, an alkylene group having 1 to 5 carbon atoms, and a cyclohexane ring are preferable because they can be easily synthesized and can suppress a decrease in voltage holding ratio after being exposed to light irradiation for a long time. Or a benzene ring is preferable.

W ³ is preferably a single bond, —O—, —COO—, —OCO—, or —O (CH ₂ ) _m — (m represents an integer of 1 to 5). More preferable is a single bond, —O—, —OCO—, or —O (CH ₂ ) _m — (m represents an integer of 1 to 5) from the viewpoint of ease of synthesis.

W ⁴ represents a nitrogen-containing aromatic heterocycle, and similarly to the above, represents a heterocycle containing a structure represented by the formula [a], formula [b] or formula [c]. Specifically, as described above, among them, pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyrimidine ring, pyridazine ring, triazine ring, triazole ring, pyrazine ring, benzimidazole ring or benzimidazole ring are preferable. . More preferred are a pyrrole ring, an imidazole ring, a pyrazole ring, a pyridine ring or a pyrimidine ring from the viewpoint that a decrease in voltage holding ratio after being exposed to light irradiation for a long time can be suppressed. Particularly preferred is an imidazole ring or a pyridine ring.

W ³ in Formula [2] is preferably bonded to a substituent that is not adjacent to Formula [a], Formula [b], and Formula [c] included in W ⁴ .

Preferred combinations of W ¹ , W ² , W ³ and W ^{4 in} the formula [2] are as shown in Tables 1 to 31 below.

Among them, (a-43) to (a-49), (a-57) to (a-63), (a-218) to (a-224), (a-232) to (a-238) , (A-323) to (a-329), (a-337) to (a-343), (a-428) to (a-434), or (a-442) to (a-448) Is preferred. More preferably, (a-44), (a-45), (a-58) or (a-44), (a-44), (a-58) or (a a-59).

As the diamine compound having the specific structure (1), a diamine compound represented by the following formula [2a] (also referred to as a specific diamine compound (1)) is preferably used.

In the formula [2a], W represents the structure represented by the formula [2].

The details and preferred combinations of W ¹ , W ² , W ³ and W ^{4 in} the formula [2] are as in the formula [2].

M1 is preferably 1 from the viewpoint of ease of synthesis.

The use ratio of the specific diamine compound (1) is preferably 1 to 60 mol% with respect to the entire diamine component from the viewpoint that the decrease in voltage holding ratio after being exposed to light irradiation for a long time can be suppressed. More preferred is 1 to 50 mol%, and particularly preferred is 5 to 50 mol%.

In addition, the specific diamine compound (1) is one or more depending on the properties such as the solubility of the specific polyimide polymer in the solvent, the liquid crystal alignment when the liquid crystal alignment film is formed, or the electric characteristics of the liquid crystal display element. Two or more kinds can be mixed and used.

When the liquid crystal aligning agent of the present invention is used for a VA mode, PSA mode or SC-PVA mode liquid crystal display element, the diamine component is represented by the following formula [3-1] or [3-2]. It is preferable to use a diamine compound having a structure (also referred to as a specific structure (2)).

In formula [3-1], Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ , Y ⁶ and n are as defined above, and among them, the following are preferable.

Y ¹ is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O— or — from the viewpoint of availability of raw materials and ease of synthesis. COO- is preferred. More preferred is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 10), —O—, —CH ₂ O— or —COO—.

Y ² is preferably a single bond or — (CH ₂ ) _b — (b is an integer of 1 to 10).

Y ³ is preferably a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O— or —COO— from the viewpoint of ease of synthesis. More preferred is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 10), —O—, —CH ₂ O— or —COO—.

Y ⁴ is preferably an organic group having 17 to 51 carbon atoms having a benzene ring, a cyclohexane ring or a steroid skeleton from the viewpoint of ease of synthesis.

Y ⁵ is preferably a benzene ring or a cyclohexane ring.

Y ⁶ is an alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine containing group having 1 to 10 carbon atoms. Alkoxyl groups are preferred. More preferably, it is an alkyl group having 1 to 12 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, or an alkoxyl group having 1 to 12 carbon atoms. Particularly preferred is an alkyl group having 1 to 9 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkoxyl group having 1 to 9 carbon atoms.

N is preferably 0 to 3 and more preferably 0 to 2 in view of availability of raw materials and ease of synthesis.

Preferred combinations of Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ , Y ⁶ and n are listed in Tables 6 to 47 on pages 13 to 34 of International Publication No. WO2011 / 132751 (published 2011.10.27). (2-1) to (2-629) listed in (1). In each table of the International Publication, Y ¹ to Y ⁶ in the present invention are shown as Y ¹ to Y ⁶ , but Y ¹ to Y ⁶ are read as Y ¹ to Y ⁶ . Further, in (2-605) to (2-629) listed in each table of the International Publication, the organic group having 17 to 51 carbon atoms having a steroid skeleton in the present invention has 12 to 20 carbon atoms having a steroid skeleton. An organic group having 12 to 25 carbon atoms having a steroid skeleton is to be read as an organic group having 17 to 51 carbon atoms having a steroid skeleton.

Among them, (2-25) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-268) to (2-315) , (2-364) to (2-387), (2-436) to (2-483), or (2-603) to (2-615) are preferred. Particularly preferred combinations are (2-49) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-603) to (2- 606), (2-607) to (2-609), (2-611), (2-612) or (2-624).

In formula [3-2], Y ⁷ and Y ⁸ are as defined above, and among them, the following are preferable.

Y ⁷ is preferably a single bond, —O—, —CH ₂ O—, —CONH—, —CON (CH ₃ ) — or —COO—. More preferably, they are a single bond, —O—, —CONH— or —COO—.

Y ⁸ is preferably an alkyl group having 8 to 18 carbon atoms.

In the present invention, the specific structure (2) is preferably a structure represented by the formula [3-1] from the viewpoint that a high and stable liquid crystal vertical alignment can be obtained.

As the diamine compound having the specific structure (2), a diamine compound represented by the following formula [3a] (also referred to as a specific diamine compound (2)) is preferably used.

In the formula [3a], Y represents a structure represented by the formula [3-1] or the formula [3-2].

The details and preferred combinations of Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ , Y ⁶ and n in Formula [3-1] are as in Formula [3-1], and Formula [3] The details and preferred combinations of Y ⁷ and Y ⁸ in -2] are as shown in the formula [3-2].

N1 is preferably 1 from the viewpoint of ease of synthesis.

Specific examples of the specific diamine compound (2) having the specific structure represented by the formula [3-1] include diamine compounds represented by the following formulas [3a-1] to [3a-31]. .

(R ¹ represents at least one linking group selected from the group consisting of —O—, —OCH ₂ —, —CH ₂ O—, —COOCH ₂ —, and —CH ₂ OCO—. R ² represents each A linear or branched alkyl group having 1 to 18 carbon atoms, a linear or branched alkoxyl group having 1 to 18 carbon atoms, a linear or branched fluorine-containing alkyl group having 1 to 18 carbon atoms, or carbon Represents a linear or branched fluorine-containing alkoxyl group of formula 1 to 18.)

(R ³ consists of —COO—, —OCO—, —CONH—, —NHCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ — and —CH ₂ —, respectively. And R ⁴ represents a linear or branched alkyl group having 1 to 18 carbon atoms, a linear or branched alkoxyl group having 1 to 18 carbon atoms, or a carbon number. 1 to 18 linear or branched fluorine-containing alkyl group, or C 1 to 18 linear or branched fluorine-containing alkoxyl group.)

(R ⁵ represents —COO—, —OCO—, —CONH—, —NHCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ —, —CH ₂ —, — R ⁶ represents at least one linking group selected from the group consisting of O— and —NH—, wherein R ⁶ represents a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, an acetyl group, an acetoxy group, respectively. And at least one selected from the group consisting of hydroxyl groups.)

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

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

(A ₄ represents a linear or branched alkyl group having 3 to 18 carbon atoms which may be substituted with a fluorine atom. A ₃ represents a 1,4-cyclohexylene group or a 1,4-phenylene group. A ₂ represents an oxygen atom or —COO— * (where a bond marked with “*” is bonded to A ₃ ) A ₁ represents an oxygen atom or —COO— * (note that “*” is attached). The bonded bond is bonded to (CH ₂ ) a ₂ ). Also, _{a 1} is an integer of 0 or 1. a ₂ represents an integer of 2 to 10. a ₃ represents an integer of 0 or 1. )

Of the above formulas [3a-1] to [3a-31], preferred diamine compounds are those represented by formula [3a-1] to formula [3a-6], formula [3a-9] to formula [3a-13] or formula [3a-13]. 3a-22] to [3a-31].

Specific examples of the specific diamine compound (2) having the specific structure (2) represented by the formula [3-2] include diamine compounds represented by the following formulas [3a-32] to [3a-35]. Is mentioned.

(A ¹ represents an alkyl group having 8 to 18 carbon atoms or a fluorine-containing alkyl group.)

When the specific diamine compound (2) is used in a VA mode, PSA mode or SC-PVA mode liquid crystal display element, it is preferably 10 to 70 mol% based on the total diamine component. More preferred is 20 to 70 mol%, and particularly preferred is 20 to 60 mol%.

In addition, the specific diamine compound (2) is one or more depending on properties such as the solubility of the specific polyimide polymer in a solvent, the liquid crystal alignment when the liquid crystal alignment film is formed, or the electric characteristics of the liquid crystal display element. Two or more kinds can be mixed and used.

In the diamine component in the present invention, the specific diamine compound (1) and the specific diamine compound (2) are mixed with a display mode of a liquid crystal display element, that is, a TN (Twisted Nematic) mode, an IPS (In-plane Switching) mode, Depending on the VA mode, PSA mode, and SC-PVA mode, they can be appropriately selected and used. Moreover, two or more types of these specific diamine compounds, that is, a plurality of types can be used.

As the diamine component for producing the specific polyimide polymer, the following diamine compounds (also referred to as other diamine compounds) can be used.
Specifically, for example, 2,4-dimethyl-m-phenylenediamine, 2,6-diaminotoluene, m-phenylenediamine, p-phenylenediamine, 2,4-diaminophenol, 3,5-diaminophenol, 3, 5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'- Diaminobiphenyl, 3,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, 3,3′-dihydroxy-4,4′-diaminobiphenyl, 3, 3'-dicarboxy-4,4'-diaminobiphenyl, 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'-diamino Diphenylamine, 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'-diaminoben Zophenone, 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diamino Naphthalene, 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 (4aminophenyl) 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, 4-bis (4-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (4-aminobenzyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 '-[1,4-phenylenebis (methylene)] dianiline, 4,4'-[1,3-phenylenebis (methylene)] dianiline, 3,4 '-[1,4-phenylenebis (methylene) )] Dianiline, 3,4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,3 ′-[1,4-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-aminobenzoate), 1, 3-phenylenebis (4-aminobenzoate), 1,3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) iso Phthalate, 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-phen Len) bis (3-aminobenzamide), N, N′-bis (4-aminophenyl) terephthalamide, N, N′-bis (3-aminophenyl) terephthalamide, N, N′-bis (4-amino) Phenyl) 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) hexa Fluoropropane, 2,2′-bis (4-aminophenyl) propane, 2,2′-bis (3-aminophenyl) propane, 2,2′-bis (3-amino-4-methylphenyl) 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-bis (3-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, , 8-bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10-bis (4-aminophenoxy) decane 1,10-bis (3-aminophenoxy) decane, 1,11-bis (4-aminophenoxy) undecane, 1,11-bis (3-aminophenoxy) undecane, 1,12-bis (4-aminophenoxy) ) Dodecane, 1,12-bis (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) methane, 1,3-diaminopropane, 1,4-diamino Butane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, Examples include 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

Further, as other diamine compounds, diamine compounds represented by the following formulas [D1] to [DA15] can also be used.

(P represents an integer of 1 to 10)

(L ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. N represents an integer of 1 to 5.)

Other diamine compounds may be used alone or in combination of two or more depending on the properties such as the solubility of the specific polyimide polymer in the solvent, the liquid crystal orientation when the liquid crystal alignment film is formed, or the electrical properties of the liquid crystal display element. Can be used.

It is preferable to use a tetracarboxylic dianhydride (also referred to as a specific tetracarboxylic acid component) represented by the following formula [4] as the tetracarboxylic acid component for producing the specific polyimide polymer.

In the formula [4], Z represents at least one structure selected from the group consisting of the structures represented by the formulas [4a] to [4k].

Z in the formula [4] is represented by the formula [4a], the formula [4c], the formula [4d], the formula [4e], from the viewpoint of the ease of synthesis and the ease of polymerization reactivity when producing the polymer. A structure represented by the formula [4f], the formula [4g] or the formula [4k] is preferable. A structure represented by the formula [4a], the formula [4e], the formula [4f], the formula [4g], or the formula [4k] is more preferable. Particularly preferred is a structure represented by the formula [4e], the formula [4f], the formula [4g] or the formula [4k].

The usage ratio of the specific tetracarboxylic acid component is preferably 1 mol% or more with respect to the total tetracarboxylic acid component. More preferably, it is 5 mol% or more. Particularly preferred is 10 mol% or more, and most preferred is 10 to 90 mol% from the viewpoint of suppressing a decrease in voltage holding ratio after exposure to light irradiation for a long time. .

Moreover, when using the tetracarboxylic-acid component of the structure shown by said Formula [4e], Formula [4f], Formula [4g], or Formula [4k], the usage-amount is 20 mol% or more of the whole tetracarboxylic-acid component. As a result, a desired effect can be obtained. Preferably, it is 30 mol% or more. Further, all of the tetracarboxylic acid component may be a tetracarboxylic acid component having a structure represented by the formula [4e], the formula [4f], the formula [4g], or the formula [4k].

As the tetracarboxylic acid component in the present invention, other tetracarboxylic acid components other than the specific tetracarboxylic acid component can be used as long as the effects of the present invention are not impaired.

Specifically, for example, pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2 , 3,6,7-anthracenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4′- Biphenyltetracarboxylic acid, bis (3,4-dicarboxyphenyl) ether, 3,3 ′, 4,4′-benzophenonetetracarboxylic acid, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4- Dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2-bis (3,4-dical) Xylphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3 , 4-dicarboxyphenyl) pyridine, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid or 1,3-diphenyl-1,2,3 Examples include 4-cyclobutanetetracarboxylic acid.

The specific tetracarboxylic acid component and other tetracarboxylic acid components depend on the properties such as the solubility of the specific polyimide polymer in the solvent, the liquid crystal alignment when the liquid crystal alignment film is formed, or the electrical characteristics of the liquid crystal display element. 1 type (s) or 2 or more types can be mixed and used.

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 dianhydride and its tetracarboxylic acid derivative 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 Or a method of obtaining a polyamic acid by reacting a tetracarboxylic acid dihalide with a primary or secondary diamine compound.

To obtain the 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 1 A method of reacting with a secondary 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 with the diamine component and the tetracarboxylic acid component in an organic solvent. The organic solvent used at that time is not particularly limited as long as the produced polyimide precursor is dissolved. Although the specific example of the organic solvent used for reaction below is given, it is not limited to these examples.

For example, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide or 1,3-dimethyl-imidazolidinone Can be mentioned. When the solvent solubility of the polyimide precursor is high, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the following formulas [D-1] to [D-3] The indicated solvents can be used.

These 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 the said solvent in the range which the produced | generated polyimide precursor does not precipitate. Moreover, since the water | moisture content in an organic solvent inhibits a polymerization reaction, and also causes the produced polyimide precursor to hydrolyze, it is preferable to use what dehydrated and dried the organic solvent.

When the diamine component and the tetracarboxylic acid component are reacted in an organic solvent, the solution in which the diamine component is dispersed or dissolved in the organic solvent is stirred, and the tetracarboxylic acid component is added as it is, or dispersed in the organic solvent or Examples include a method of adding by dissolving, a method of adding a diamine component to a solution obtained by dispersing or dissolving a tetracarboxylic acid component in an organic solvent, and a method of adding a diamine component and a tetracarboxylic acid component alternately. Any of these methods may be used. In addition, when reacting by using a plurality of diamine components and 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. In this case, the polymerization temperature can be selected from -20 ° C to 150 ° C, but is preferably in the range of -5 ° C to 100 ° C. 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, it is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The initial stage of the polymerization reaction can be performed at a high concentration, and then an organic solvent can be added.

In the polymerization reaction of the polyimide precursor, the ratio of the total number of moles of the diamine component to the total number of moles of the tetracarboxylic acid component is preferably 0.8 to 1.2. Similar to the normal polymerization reaction, the closer the molar ratio is to 1.0, the higher the molecular weight of the polyimide precursor produced.

Polyimide is a polyimide obtained by ring closure of the polyimide precursor, and the ring closure rate (also referred to as imidation rate) of the amic acid group does not necessarily need to be 100%, and can be arbitrarily adjusted according to the application and purpose. can do. Especially, it is preferable that the specific polyimide-type polymer in this invention is the polyimide which imidated the polyimide precursor. In that case, the imidation ratio is preferably 40 to 90%. More preferred is 50 to 90%.

Examples of the method for imidizing the polyimide precursor include thermal imidization in which the polyimide precursor solution is heated as it is, or catalytic imidization in which a catalyst is added to the polyimide precursor solution. The temperature when the polyimide precursor is thermally imidized in the solution is 100 ° C. to 400 ° C., preferably 120 ° C. to 250 ° C., and it is preferable to carry out while removing water generated by the imidation reaction from the system.

The catalyst imidation of the polyimide precursor can be performed by adding a basic catalyst and an acid anhydride to the polyimide precursor solution and stirring at -20 to 250 ° C, preferably 0 to 180 ° C. 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, preferably 3 to 30 mol of the amido acid group. Is double. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Of these, pyridine is preferable because it has a basicity suitable for advancing the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. Of these, use of acetic anhydride is preferable because purification after completion of the reaction is facilitated. The imidation ratio 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 recovered by filtration, and then dried at normal temperature or under reduced pressure at room temperature or by heating. Further, when the polymer recovered by precipitation is redissolved in an organic solvent and reprecipitated and recovered, the impurities in the polymer can be reduced. 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 improved.

The molecular weight of the polyimide-based polymer is the weight average molecular weight measured by GPC (Gel Permeation Chromatography) method when considering the strength of the liquid crystal alignment film obtained therefrom, the workability at the time of forming the liquid crystal alignment film, and the coating properties. It is preferably 5,000 to 1,000,000. Of these, 10,000 to 150,000 is preferable.

As described above, the specific polyimide polymer in the present invention is a polyimide obtained by catalytic imidization of the polyimide precursor from the viewpoint that it can suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time. Preferably there is. It is preferable that the imidation ratio in that case is the said range.

<Liquid crystal alignment agent>
The liquid crystal aligning agent of the present invention is a coating solution for forming a liquid crystal alignment film (also referred to as a resin film), and preferably contains a specific compound, a polymer, and a solvent.

The use ratio of the specific compound in the liquid crystal alignment treatment agent is preferably as follows. That is, it is preferably 1 to 30 parts by mass with respect to 100 parts by mass of all the polymers. More preferred is 1 to 20 parts by mass, and particularly preferred is 3 to 15 parts by mass.

As the polymer component in the liquid crystal aligning agent, it is preferable to use a specific polyimide polymer, but other polymers may be mixed. In that case, the content of the other polymer is preferably 0.5 to 15 parts by mass with respect to 100 parts by mass of the specific polyimide polymer. More preferred is 1 to 10 parts by mass. Examples of the other polymer include the above-mentioned acrylic polymer, methacrylic polymer, novolac resin, polyhydroxystyrene, polyamide, polyester, cellulose, and polysiloxane.

The solvent in the liquid crystal aligning agent is preferably 70 to 99.9% by mass in terms of forming a uniform liquid crystal aligning film by coating. This content can be appropriately changed depending on 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 polymer. Although the specific example of the good solvent at the time of using a specific polyimide polymer 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 or γ-butyrolactone is preferably used.

Furthermore, when the solubility of the specific polyimide polymer in the solvent is high, it is preferable to use the solvent represented by the formula [D-1] to the formula [D-3].

The proportion of the good solvent used in the liquid crystal aligning agent is preferably 10 to 100% by mass of the total solvent contained in the liquid crystal aligning agent. More preferred is 20 to 90% by mass, and particularly preferred is 30 to 80% by mass.

As long as the effects of the present invention are not impaired, a solvent (also referred to as a poor solvent) that improves the coating properties and surface smoothness of the liquid crystal alignment film when the liquid crystal alignment treatment agent is applied is used as the liquid crystal alignment treatment agent. it can. 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- Ethane All, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol 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, -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 mono Acetate, 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, Methyl acetate, 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-methoxy Ethyl propionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, methyl lactate, ethyl lactate, lactate n-propyl ester, lactate n-butyl ester, Examples thereof include isoamyl lactate and solvents represented by the above formulas [D-1] to [D-3].

Among them, 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, dipropylene glycol dimethyl ether, or the above formulas [D-1] to [D −3] is preferably used.

The proportion of these poor solvents used is preferably 1 to 70% by mass of the total solvent contained in the liquid crystal aligning agent. More preferred is 1 to 60% by mass, and particularly preferred is 5 to 60% by mass.

The liquid crystal aligning agent of the present invention comprises a crosslinkable compound selected from the group consisting of an epoxy group, an isocyanate group, an oxetane group and a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group and an alkoxyalkyl group having 1 to 3 carbon atoms. It is preferable to introduce a crosslinkable compound selected from the group or a crosslinkable compound having a polymerizable unsaturated bond group (also collectively referred to as a specific crosslinkable compound). In that case, it is necessary to have two or more of these groups in the 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 the formulas [4a] to [4k] published on pages 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 on pages 76 to 82 of International Publication No. WO2012 / 014898 (published on 2012.2.2). It is done.

Examples of the crosslinkable compound having at least one group selected from the group consisting of a hydroxyl group and an alkoxyl group include, for example, amino resins having a hydroxyl group or an alkoxyl group, such as melamine resin, urea resin, guanamine resin, glycoluril- Examples include formaldehyde resin, succinylamide-formaldehyde resin, and 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, 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.

As such a melamine derivative or benzoguanamine derivative, for example, MX-750 in which an average of 3.7 methoxymethyl groups are substituted per one triazine ring in a commercially available product, and an average of 5. methoxymethyl groups per one 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 ester Methoxymethylated 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 benzene having a hydroxyl group or an alkoxyl group, or phenolic compounds include 1,3,5-tris (methoxymethyl) benzene, 1,2,4-tris (isopropoxymethyl) benzene, and 1,4-bis. Examples thereof include (sec-butoxymethyl) benzene and 2,6-dihydroxymethyl-p-tert-butylphenol. More specifically, the crosslinkable compounds represented by the formulas [6-1] to [6-48] described 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 (meta ) 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 hydroxypivalate neopentyl glycol Examples thereof include crosslinkable compounds having two polymerizable unsaturated groups in the molecule such as di (meth) acrylate.

The content of the specific crosslinkable compound in the liquid crystal aligning agent is preferably 1 to 50 parts by mass with respect to 100 parts by mass of all the polymer components. More preferred is 1 to 30 parts by mass, and particularly preferred is 1 to 10 parts by mass because the crosslinking reaction proceeds and the desired effect is exhibited.

As the liquid crystal alignment treatment agent, a compound that improves the film thickness uniformity and surface smoothness of the liquid crystal alignment film when the liquid crystal alignment treatment agent is applied can be used as long as the effects of the present invention are not impaired. Furthermore, a compound that improves the adhesion between the liquid crystal alignment film and the substrate can also be used.

Examples of the compound that improves the uniformity of the film thickness and the surface smoothness of the liquid crystal alignment film include a fluorine-based surfactant, a silicone-based surfactant, and a nonionic surfactant. 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 (above, Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (above, manufactured by Asahi Glass). The use ratio of these surfactants is preferably 0.01 to 2 parts by mass with respect to 100 parts by mass of all the polymer components contained in the liquid crystal aligning agent. More preferred is 0.01 to 1 part by mass.

Specific examples of compounds that improve the adhesion between the liquid crystal alignment film and the substrate include functional silane-containing compounds and epoxy group-containing compounds. For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxy Carbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-tri Toxisilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxy Silane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyl Trimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, poly Lopylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl -2,4-hexanediol, N, N, N ′, N ′,-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane or N, N, N ′ , N ′,-tetraglycidyl-4,4′-diaminodiphenylmethane and the like.

The use ratio of the compound to be adhered to these substrates is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of all the polymer components contained in the liquid crystal aligning agent. More preferred is 1 to 20 parts by mass. If it is less than 0.1 part by mass, the effect of improving the adhesion cannot be expected, and if it exceeds 30 parts by mass, the storage stability of the liquid crystal aligning agent may be deteriorated.

In addition to the compounds other than the above, the liquid crystal aligning agent includes a dielectric or conductive material for changing the electrical properties such as the dielectric constant and conductivity of the liquid crystal alignment film as long as the effects of the present invention are not impaired. Substances may be added.

<Liquid crystal alignment film and liquid crystal display element>
The liquid crystal alignment treatment agent of the present invention can be used as a liquid crystal alignment film after being applied and baked on a substrate and then subjected to alignment treatment by rubbing treatment or light irradiation. In the case of a VA mode liquid crystal display element or the like, it can be used as a liquid crystal alignment film without alignment treatment. The substrate used at this time is not particularly limited as long as it is a highly transparent substrate. In addition to a glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate can also be used. From the viewpoint of simplifying the process, it is preferable to use a substrate on which an ITO (Indium Tin Oxide) electrode for driving a liquid crystal is formed. In the reflective liquid crystal display element, an opaque substrate such as a silicon wafer can be used if only one substrate is used, and a material that reflects light such as aluminum can be used as an electrode in this case.

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

After the liquid crystal alignment treatment agent is applied on the substrate, it is preferably 30 to 300 ° C., depending on the solvent used for the liquid crystal alignment treatment agent, by a heating means such as a hot plate, a thermal circulation oven or an IR (infrared) oven. The liquid crystal alignment film can be obtained by evaporating the solvent at a temperature of 30 to 250 ° C. If the thickness of the liquid crystal alignment film after baking is too thick, it is disadvantageous in terms of power consumption of the liquid crystal display element, and if it is too thin, the reliability of the liquid crystal display element may be lowered. Is 10 to 100 nm. When the liquid crystal is tilted or horizontally aligned as in the TN mode or IPS mode liquid crystal display element, the fired liquid crystal alignment film is treated by rubbing or irradiation with polarized ultraviolet rays.

The liquid crystal display element of the present invention is a liquid crystal display element obtained by obtaining a substrate with a liquid crystal alignment film from the liquid crystal alignment treatment agent of the present invention by the above-described method and then preparing a liquid crystal cell by a known method.

As a method for producing a liquid crystal cell, for example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, spacers are dispersed on the liquid crystal alignment film of one substrate, and the liquid crystal alignment film surface is on the inside, A method in which the other substrate is bonded and liquid crystal is injected under reduced pressure, or a liquid crystal is dropped on the liquid crystal alignment film surface on which spacers are dispersed, and then the substrate is bonded and sealed (ODF: One ： Drop Filling) For example).

The liquid-crystal aligning agent of this invention has a liquid-crystal layer between a pair of board | substrates provided with the electrode, The liquid crystal containing the polymeric compound superposed | polymerized by at least one of an active energy ray and a heat | fever between a pair of board | substrates. The composition is also preferably used for a liquid crystal display device produced through a step of polymerizing a polymerizable compound by at least one of irradiation with active energy rays and heating while applying a voltage between electrodes. Here, ultraviolet rays are suitable as the active energy ray. The wavelength of ultraviolet rays is 300 to 400 nm, preferably 310 to 360 nm. In the case of polymerization by heating, the heating temperature is 40 to 120 ° C, preferably 60 to 80 ° C. Moreover, you may perform an ultraviolet-ray and a heating simultaneously.

The above-mentioned liquid crystal display element controls the pretilt of liquid crystal molecules by the PSA mode method. In the PSA mode, a small amount of a photopolymerizable compound, for example, a photopolymerizable monomer is mixed in the liquid crystal material, and after assembling the liquid crystal cell, a predetermined voltage is applied to the liquid crystal layer and the photopolymerizable compound is irradiated with ultraviolet light. The pretilt of the liquid crystal molecules is controlled by the produced polymer. Since the alignment state of the liquid crystal molecules when the polymer is formed is stored even after the voltage is removed, the pretilt of the liquid crystal molecules can be adjusted by controlling the electric field formed in the liquid crystal layer. The PSA mode does not require a rubbing process and is suitable for forming a vertical alignment type liquid crystal layer in which it is difficult to control the pretilt by the rubbing process. That is, in the liquid crystal display element of the present invention, after obtaining a substrate with a liquid crystal alignment film from the liquid crystal alignment treatment agent by the above-described method, a liquid crystal cell is prepared, and a polymerizable compound is polymerized by at least one of ultraviolet irradiation and heating. Thus, the alignment of liquid crystal molecules can be controlled.

An example of the production of a PSA mode liquid crystal cell is as follows. That is, a liquid crystal cell is manufactured by the manufacturing method described above. In the liquid crystal at that time, a polymerizable compound that is polymerized by heat or ultraviolet irradiation is mixed. Examples of the polymerizable compound include compounds having at least one polymerizable unsaturated group such as an acrylate group or a methacrylate group in the molecule. In that case, the polymerizable compound is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the liquid crystal component. When the polymerizable compound is less than 0.01 part by mass, the polymerizable compound is not polymerized and the orientation of the liquid crystal cannot be controlled, and when it exceeds 10 parts by mass, the amount of the unreacted polymerizable compound increases and the liquid crystal display element. The seizure characteristics of the steel deteriorate. After the liquid crystal cell is produced, the polymerizable compound is polymerized by irradiating heat or ultraviolet rays while applying an AC or DC voltage to the liquid crystal cell. Thereby, the alignment of the liquid crystal molecules can be controlled.

Furthermore, the liquid crystal aligning agent of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and a polymerizable group that is polymerized by at least one of active energy rays and heat between the pair of substrates. It can also be used for a liquid crystal display element manufactured through a process of arranging a liquid crystal alignment film containing and applying a voltage between electrodes, that is, an SC-PVA mode. Here, ultraviolet rays are suitable as the active energy ray. The wavelength of ultraviolet rays is 300 to 400 nm, and more preferably 310 to 360 nm. In the case of polymerization by heating, the heating temperature is 40 to 120 ° C, more preferably 60 to 80 ° C. Moreover, you may perform an ultraviolet-ray and a heating simultaneously.

In order to obtain a liquid crystal alignment film containing a polymerizable group that is polymerized from at least one of active energy rays and heat, a method of adding a compound containing this polymerizable group to the liquid crystal aligning agent, A method using a coalescing component may be mentioned.

An example of the production of an SC-PVA mode liquid crystal cell is as follows. That is, a liquid crystal cell is manufactured by the manufacturing method described above. Thereafter, the orientation of the liquid crystal molecules can be controlled by irradiating heat or ultraviolet rays while applying an AC or DC voltage to the liquid crystal cell.

As described above, by using the liquid crystal alignment treatment agent of the present invention, it is possible to suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time, and in addition, liquid crystal even under high temperature and high humidity conditions. A liquid crystal alignment film in which display unevenness does not occur near the frame of the display element can be provided. Therefore, the liquid crystal display element manufactured using the liquid crystal aligning agent of the present invention has excellent reliability, and can be suitably used for large liquid crystal televisions, small and medium car navigation systems, smartphones, and the like. . In particular, the liquid crystal alignment treatment agent of the present invention is useful for a liquid crystal alignment film of a liquid crystal display device using a VA mode, a PSA mode, and an SC-PVA mode.

The present invention will be described more specifically with reference to the following examples, but is not limited thereto.
Abbreviations used in the synthesis examples, examples and comparative examples are as follows.
(Specific compounds)
S1: Phosphotungstic acid (manufactured by Nippon Shin Metals)
S2: Phosphomolybdic acid (12 molybdo (IV) phosphoric acid n hydrate) (manufactured by Kanto Chemical Co., Inc.)

(Specific diamine compound (1))
A1: Diamine compound represented by the following formula [A1] A2: Diamine compound represented by the following formula [A2]

(Specific diamine compound (2))
B1: 1,3-diamino-4- [4- (trans-4-n-heptylcyclohexyl) phenoxy] benzene B2: 1,3-diamino-5- [4- (trans-4-n-heptylcyclo) Hexyl) phenoxymethyl] benzene B3: 1,3-diamino-4- {4- [trans-4- (trans-4-n-pentylcyclohexyl) cyclohexyl] phenoxy} benzene B4: Diamine compound represented by B4] B5: 1,3-diamino-4-octadecyloxybenzene

(Other diamine compounds)
C1: p-phenylenediamine C2: m-phenylenediamine C3: diamine compound represented by the following formula [C3] C4: 4,4′-diaminodiphenylamine C5: 3,5-diaminobenzoic acid

(Specific tetracarboxylic dianhydride)
D1: 1,2,3,4-cyclobutanetetracarboxylic dianhydride D2: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride D3: the following formula [D3 D4: tetracarboxylic dianhydride represented by the following formula [D4] D5: tetracarboxylic dianhydride represented by the following formula [D5]

(Crosslinkable compound)
M1: Crosslinkable compound represented by the following formula [M1]

(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
DME: Dipropylene glycol dimethyl ether

"Molecular weight measurement of polyimide polymer"
Using a normal temperature gel permeation chromatography (GPC) apparatus (GPC-101, manufactured by Showa Denko) and a column (KD-803, KD-805, manufactured by Shodex), the measurement was performed as follows.

Column temperature: 50 ° C
Eluent: N, N′-dimethylformamide (as additive, lithium bromide-hydrate (LiBr · H ₂ O) 30 mmol / L (liter), phosphoric acid / anhydrous crystal (o-phosphoric acid) 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 rate of polyimide polymer"
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 machine (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 that appear in the vicinity of 9.5 ppm to 10.0 ppm. It calculated | required by the following formula | equation using the integrated value.

Imidization rate (%) = (1−α · x / y) × 100
(X is the accumulated proton peak value derived from NH group of amic acid, y is the accumulated peak value of reference proton, α is the reference proton for one NH group proton of amic acid in the case of polyamic acid (imidation rate is 0%) The number ratio.

"Synthesis of polyimide polymers"
<Synthesis Example 1>
D4 (9.65 g, 32.1 mmol), B5 (1.36 g, 3.61 mmol) and C1 (3.52 g, 32.6 mmol) were mixed in NMP (30.5 g) and reacted at 40 ° C. for 6 hours. Then, D1 (0.70 g, 3.57 mmol) and NMP (15.2 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution having a resin solid content concentration of 25 mass%.

After adding NMP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (3.90 g) and pyridine (2.40 g) were added as an imidization catalyst, and the mixture was kept at 70 ° C. for 4 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (1). The imidation ratio of this polyimide was 85%, the number average molecular weight was 19,800, and the weight average molecular weight was 51,800.

<Synthesis Example 2>
D2 (5.95 g, 23.8 mmol), B3 (4.47 g, 10.3 mmol), C1 (1.49 g, 13.8 mmol) and C3 (2.10 g, 10.3 mmol) NEP (32.0 g) After mixing at 80 ° C. for 5 hours, D1 (2.00 g, 10.2 mmol) and NEP (16.0 g) were added, and the mixture was reacted at 40 ° C. for 6 hours. % Polyamic acid solution (2) was obtained. The number average molecular weight of this polyamic acid was 20,200, and the weight average molecular weight was 68,300.

<Synthesis Example 3>
After adding NEP to the polyamic acid solution (2) (30.0 g) obtained in Synthesis Example 2 and diluting to 6% by mass, acetic anhydride (4.50 g) and pyridine (3.30 g) were used as imidization catalysts. In addition, the mixture was reacted at 80 ° C. for 4 hours. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (3). The imidation ratio of this polyimide was 80%, the number average molecular weight was 18,300, and the weight average molecular weight was 46,800.

<Synthesis Example 4>
D2 (2.98 g, 11.9 mmol), A1 (1.25 g, 5.16 mmol), B3 (2.23 g, 5.15 mmol) and C1 (0.74 g, 6.84 mmol) with NEP (16.4 g) After mixing at 80 ° C. for 5 hours, D1 (1.00 g, 5.10 mmol) and NEP (8.21 g) were added, and the mixture was reacted at 40 ° C. for 6 hours. % Polyamic acid solution was obtained.

After adding NEP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (4.50 g) and pyridine (3.30 g) were added as an imidization catalyst, and the mixture was heated at 80 ° C. for 4 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (4). The imidation ratio of this polyimide was 81%, the number average molecular weight was 17,800, and the weight average molecular weight was 44,900.

<Synthesis Example 5>
D2 (2.17 g, 8.67 mmol), A1 (1.28 g, 5.28 mmol), B1 (2.67 g, 7.02 mmol) and C1 (0.57 g, 5.27 mmol) NMP (16.8 g) After mixing at 80 ° C. for 5 hours, D1 (1.70 g, 8.67 mmol) and NMP (8.39 g) were added and reacted at 40 ° C. for 6 hours to give a resin solid content concentration of 25 mass. % Polyamic acid solution was obtained.

After adding NMP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (3.80 g) and pyridine (2.40 g) were added as an imidization catalyst, and the mixture was heated at 60 ° C. for 2 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (5). The imidation ratio of this polyimide was 56%, the number average molecular weight was 17,000, and the weight average molecular weight was 43,200.

<Synthesis Example 6>
D2 (2.17 g, 8.67 mmol), A1 (1.28 g, 5.28 mmol), B5 (2.65 g, 7.04 mmol) and C1 (0.57 g, 5.27 mmol) NMP (16.7 g) After mixing at 80 ° C. for 5 hours, D1 (1.70 g, 8.67 mmol) and NMP (8.36 g) were added and reacted at 40 ° C. for 6 hours to give a resin solid content concentration of 25 mass. % Polyamic acid solution was obtained.

After adding NMP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (3.80 g) and pyridine (2.40 g) were added as an imidization catalyst, and the mixture was heated at 60 ° C. for 2 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (6). The imidation ratio of this polyimide was 55%, the number average molecular weight was 16,300, and the weight average molecular weight was 41,100.

<Synthesis Example 7>
D2 (1.31 g, 5.24 mmol), A1 (0.86 g, 3.55 mmol), B2 (2.80 g, 7.10 mmol), C1 (0.57 g, 5.27 mmol) and C4 (0.35 g, 1.76 mmol) was mixed in NMP (16.6 g) and reacted at 80 ° C. for 5 hours, then D1 (2.40 g, 12.2 mmol) and NMP (8.29 g) were added, and 6 The reaction was carried out for a time to obtain a polyamic acid solution having a resin solid content concentration of 25% by mass.

After adding NMP to the obtained polyamic-acid solution (30.0g) and diluting to 6 mass%, acetic anhydride (3.80g) and a pyridine (2.40g) are added as an imidation catalyst, and 2. at 60 degreeC. The reaction was allowed for 5 hours. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (7). The imidation ratio of this polyimide was 60%, the number average molecular weight was 17,500, and the weight average molecular weight was 43,800.

<Synthesis Example 8>
D2 (2.04 g, 8.15 mmol), A2 (1.07 g, 4.13 mmol), B2 (2.94 g, 7.45 mmol), C1 (0.36 g, 3.33 mmol) and C5 (0.25 g, 1.64 mmol) was mixed in NEP (16.5 g) and reacted at 80 ° C. for 5 hours, then D1 (1.60 g, 8.16 mmol) and NEP (8.26 g) were added, and 6 ° C. at 6 ° C. The reaction was carried out for a time to obtain a polyamic acid solution having a resin solid content concentration of 25% by mass.

After adding NMP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (4.50 g) and pyridine (3.30 g) were added as an imidization catalyst, and the mixture was heated at 80 ° C. for 3 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (8). The imidation ratio of this polyimide was 72%, the number average molecular weight was 16,800, and the weight average molecular weight was 41,900.

<Synthesis Example 9>
D2 (2.30 g, 9.19 mmol), A1 (0.90 g, 3.71 mmol), B4 (2.29 g, 4.65 mmol) and C2 (1.11 g, 10.3 mmol) were added to NMP (16.8 g). After mixing at 80 ° C. for 5 hours, D1 (1.80 g, 9.18 mmol) and NMP (8.39 g) were added and reacted at 40 ° C. for 6 hours to give a resin solid content concentration of 25 mass. % Polyamic acid solution was obtained.

After adding NMP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (3.80 g) and pyridine (2.40 g) were added as an imidization catalyst, and the mixture was heated at 60 ° C. for 2 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (9). The imidation ratio of this polyimide was 52%, the number average molecular weight was 15,300, and the weight average molecular weight was 39,700.

<Synthesis Example 10>
D3 (7.10 g, 31.7 mmol), A1 (3.11 g, 12.8 mmol), B2 (5.06 g, 12.8 mmol) and C1 (0.69 g, 6.38 mmol) were added to NMP (47.9 g). Then, the mixture was reacted at 40 ° C. for 8 hours to obtain a polyamic acid solution having a resin solid content concentration of 25% by mass.

After adding NMP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (4.50 g) and pyridine (3.30 g) were added as an imidization catalyst, and the mixture was heated at 80 ° C. for 3 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (10). The imidation ratio of this polyimide was 73%, the number average molecular weight was 18,600, and the weight average molecular weight was 48,400.

<Synthesis Example 11>
D4 (3.22 g, 10.7 mmol), A1 (0.38 g, 1.57 mmol), B1 (2.95 g, 7.75 mmol), C2 (0.34 g, 3.14 mmol) and C4 (0.62 g, 3.11 mmol) in NMP (16.8 g) and reacted at 80 ° C. for 5 hours, then D1 (0.90 g, 4.59 mmol) and NMP (8.39 g) were added, The reaction was carried out for a time to obtain a polyamic acid solution having a resin solid content concentration of 25% by mass.

After adding NEP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (4.50 g) and pyridine (3.30 g) were added as an imidization catalyst, and the mixture was heated at 80 ° C. for 4 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (11). The imidation ratio of this polyimide was 85%, the number average molecular weight was 16,200, and the weight average molecular weight was 41,500.

<Synthesis Example 12>
D4 (3.67 g, 12.2 mmol), A2 (1.00 g, 3.86 mmol), B3 (2.35 g, 5.43 mmol), C1 (0.50 g, 4.62 mmol) and C3 (0.32 g, 1.57 mmol) was mixed in NMP (16.9 g) and reacted at 80 ° C. for 5 hours, and then D1 (0.60 g, 3.06 mmol) and NMP (8.44 g) were added. The reaction was carried out for a time to obtain a polyamic acid solution having a resin solid content concentration of 25% by mass.

After adding NEP to the obtained polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (4.50 g) and pyridine (3.30 g) were added as an imidization catalyst, and the mixture was heated at 80 ° C. for 3 hours. Reacted. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (12). The imidation ratio of this polyimide was 72%, the number average molecular weight was 17,500, and the weight average molecular weight was 43,100.

<Synthesis Example 13>
D2 (2.48 g, 9.91 mmol), A1 (1.62 g, 6.69 mmol), B2 (2.64 g, 6.69 mmol) and C1 (0.36 g, 3.33 mmol) with NMP (17.0 g) After mixing at 80 ° C. for 5 hours, D5 (1.40 g, 6.60 mmol) and NMP (8.50 g) were added, and the mixture was reacted at 40 ° C. for 6 hours. % Polyamic acid solution was obtained.

To the obtained polyamic acid solution (30.0 g), NEP was added to dilute to 6% by mass, and then acetic anhydride (4.50 g) and pyridine (3.30 g) were added as an imidization catalyst. The reaction was allowed for 5 hours. This reaction solution was put into methanol (460 ml), and the resulting precipitate was separated by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (13). The imidation ratio of this polyimide was 74%, the number average molecular weight was 16,200, and the weight average molecular weight was 41,500.

Table 32 and Table 33 show the polyimide polymers obtained in the synthesis examples.

* 1: Polyamic acid.

"Manufacture of liquid crystal alignment treatment agent"
In the examples and comparative examples described later, production examples of the liquid crystal aligning agent are described. Moreover, this liquid crystal aligning agent is used also for preparation of a liquid crystal display element, and its evaluation. Tables 34 to 36 show the liquid crystal aligning agents obtained in the examples and comparative examples.

"Evaluation of inkjet coating properties of liquid crystal alignment treatment agents"
Ink jet coatability was evaluated using the liquid crystal aligning agent obtained in Example 7 and Example 11 described later. Specifically, a substrate with an ITO (indium tin oxide) electrode (length: 100 mm) obtained by pressure-filtering these liquid crystal alignment treatment agents with a membrane filter having a pore diameter of 1 μm and washing with pure water and IPA (isopropyl alcohol). The coating was performed on an ITO surface having a width of 100 mm and a thickness of 0.7 mm under the conditions of a coating area of 70 × 70 mm, a nozzle pitch of 0.423 mm, a scan pitch of 0.5 mm, and a coating speed of 40 mm / second. At that time, HIS-200 (manufactured by Hitachi Plant Technology Co., Ltd.) was used as the ink jet coater. The time from application to temporary drying was 60 seconds, and the temporary drying was performed on a hot plate at 70 ° C. for 5 minutes.

The applicability was evaluated by visually observing the coating surface of the substrate with a liquid crystal alignment film obtained above. Specifically, the coating film surface was visually observed under a sodium lamp to confirm the presence or absence of pinholes. As a result, in any of the liquid crystal alignment films obtained in any of the examples, no pinhole was observed on the coating film surface, and a liquid crystal alignment film having excellent coating properties was obtained.

"Evaluation of display unevenness characteristics near the frame of a liquid crystal cell (normal cell)"
The liquid crystal aligning agents obtained in Examples and Comparative Examples described later were pressure filtered through a membrane filter having a pore diameter of 1 μm and washed with pure water and IPA (40 mm long × 30 mm wide, Spin coat on ITO surface with a thickness of 0.7mm), heat treatment at 100 ° C for 5 minutes on hot plate, and heat treatment at 230 ° C for 30 minutes in a heat-circulating clean oven. An ITO substrate with a film was obtained. In addition, the liquid crystal aligning agent of Example 7 and Example 11 produced the board | substrate on the conditions similar to said "evaluation of the inkjet applicability | paintability of a liquid crystal aligning agent". And a substrate with an ITO electrode cleaned by IPA (length 40 mm × width 30 mm, thickness 0.7 mm), and then heat-treated at 230 ° C. for 30 minutes in a thermal circulation clean oven, An ITO substrate with a liquid crystal alignment film having a thickness of 100 nm was used.

Next, the substrate surface of this substrate is rubbed with a rubbing apparatus having a roll diameter of 120 mm using a rayon cloth under the conditions of a roll rotation speed of 1000 rpm, a roll traveling speed of 50 mm / sec, and an indentation amount of 0.1 mm. did.

Thereafter, two substrates after the rubbing treatment were prepared, combined with a 6 μm spacer sandwiched with the coating surface on the inside, and the periphery was adhered with a sealant to produce an empty cell. Liquid crystal was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain a liquid crystal cell. In Example 1 and Comparative Example 1, MLC-3018U (manufactured by Merck Japan) was used for the liquid crystal, and in other examples and comparative examples, MLC-6608 (manufactured by Merck Japan) was used for the liquid crystal. It was.

Using the obtained liquid crystal cell, display unevenness characteristics near the frame of the liquid crystal cell were evaluated. Specifically, liquid crystal orientation in the vicinity of the sealant was evaluated by visual observation using a polarizing plate and a backlight. As a result, all liquid crystal cells obtained in Examples and Comparative Examples showed uniform liquid crystal alignment.

Thereafter, the liquid crystal cell was stored in a high-temperature and high-humidity tank having a temperature of 80 ° C. and a humidity of 90% for 96 hours, and the liquid crystal orientation in the vicinity of the sealant was evaluated under the same conditions as described above. The evaluation was such that, after storage in a high-temperature and high-humidity tank, the liquid crystal alignment disorder was not observed in the vicinity of the sealant, and the evaluation was excellent (good display in Tables 37 to 39). Tables 37 to 39 show the results of display unevenness characteristics in the vicinity of the frame of the liquid crystal cell after storage in a high temperature and high humidity tank.

"Evaluation of voltage holding ratio (normal cell)"
The voltage holding ratio was evaluated using a liquid crystal cell manufactured under the same conditions as those described above for “evaluation of display unevenness characteristics in the vicinity of the frame of the liquid crystal cell (normal cell)”. Specifically, a voltage of 1 V is applied to the liquid crystal cell obtained by the above method at a temperature of 80 ° C. for 60 μs, the voltage after 50 ms is measured, and the voltage holding ratio ( (Also referred to as VHR). The measurement was performed using a voltage holding ratio measuring device (VHR-1) (manufactured by Toyo Technica Co., Ltd.) with settings of Voltage: ± 1 V, Pulse Width: 60 μs, and Frame Period: 50 ms.

Furthermore, a UV light of 50 J / cm ^{2 in} terms of 365 nm was converted into a liquid crystal cell for which the measurement of the voltage holding ratio immediately after the liquid crystal cell was finished, using a desktop UV curing device (HCT3B28HEX-1) (manufactured by Senlite). Irradiation was performed, and the voltage holding ratio was measured under the same conditions as described above.

In this evaluation, the value of the voltage holding ratio immediately after the production of the liquid crystal cell is high, and further, the value after the ultraviolet irradiation (also called after the ultraviolet irradiation) with respect to the value of the voltage holding ratio immediately after the production of the liquid crystal cell (also referred to as the initial). ), The smaller the decrease, the better the evaluation. Tables 37 to 39 show the values of each VHR.

<Example 1>
NMP (7.83 g) and γ-BL (23.5 g) were added to the polyimide powder (1) (2.50 g) obtained in Synthesis Example 1, and dissolved by stirring at 70 ° C. for 24 hours. S1 (0.25g) and BCS (7.83g) were added to this solution, and it stirred at 25 degreeC for 6 hours, 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.

<Example 2>
To the polyamic acid solution (2) (10.0 g) having a resin solid content concentration of 25.0% by mass obtained in Synthesis Example 2, S1 (0.125 g), NEP (14.0 g) and PB (17.6 g) And stirred at 25 ° C. for 6 hours 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.
<Example 3>

NEP (23.5 g) was added to the polyimide powder (3) (2.50 g) obtained in Synthesis Example 3, and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S1 (0.25 g), BCS (3.92 g) and PB (11.8 g) were added and stirred at 25 ° C. for 6 hours 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.

In addition, regarding “evaluation of display unevenness characteristics in the vicinity of the frame of the liquid crystal cell (normal cell)”, when stored in a high-temperature and high-humidity tank at a temperature of 80 ° C. and a humidity of 90% as an emphasis test together with the above-mentioned standard test for 144 hours. Was also evaluated (other conditions are the same as those described above). As a result, disorder of the liquid crystal alignment was observed in the liquid crystal cell in a region having a width of 0.5 cm from the sealant.

<Example 4>
NEP (23.5 g) was added to the polyimide powder (4) (2.50 g) obtained in Synthesis Example 4 and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S1 (0.25 g), BCS (3.92 g) and PB (11.8 g) were added and stirred at 25 ° C. for 6 hours 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.

In addition, regarding “evaluation of display unevenness characteristics in the vicinity of the frame of the liquid crystal cell (normal cell)”, when stored in a high-temperature and high-humidity tank at a temperature of 80 ° C. and a humidity of 90% as an emphasis test together with the above-mentioned standard test for 144 hours. Was also evaluated (other conditions are the same as those described above). As a result, no disorder in the liquid crystal alignment was observed in the vicinity of the sealing agent in the liquid crystal cell.

<Example 5>
NEP (23.5 g) was added to the polyimide powder (5) (2.50 g) obtained in Synthesis Example 5, and dissolved by stirring at 70 ° C. for 24 hours. S1 (0.175g) and PB (15.7g) were added to this solution, and it stirred at 25 degreeC for 6 hours, and obtained the 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.

In addition, regarding “evaluation of display unevenness characteristics in the vicinity of the frame of the liquid crystal cell (normal cell)”, when stored in a high-temperature and high-humidity tank at a temperature of 80 ° C. and a humidity of 90% as an emphasis test together with the standard test, Was also evaluated (other conditions are the same as those described above). As a result, no disorder in the liquid crystal alignment was observed in the vicinity of the sealing agent in the liquid crystal cell.

<Example 6>
NEP (23.5 g) was added to the polyimide powder (6) (2.50 g) obtained in Synthesis Example 6 and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S1 (0.175 g) and PB (15.7 g) were added and stirred at 25 ° C. for 6 hours 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.

In addition, regarding “evaluation of display unevenness characteristics in the vicinity of the frame of the liquid crystal cell (normal cell)”, when stored in a high-temperature and high-humidity tank at a temperature of 80 ° C. and a humidity of 90% as an emphasis test together with the standard test, Was also evaluated (other conditions are the same as those described above). As a result, disorder of the liquid crystal alignment was observed in the vicinity of the sealing agent in the liquid crystal cell.

<Example 7>
NEP (20.7 g) was added to the polyimide powder (7) (1.50 g) obtained in Synthesis Example 7 and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S2 (0.105 g), PB (16.5 g) and DME (4.14 g) were added and stirred at 25 ° C. for 6 hours 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.

<Example 8>
NMP (23.5 g) was added to the polyimide powder (8) (2.50 g) obtained in Synthesis Example 8, and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S1 (0.075 g), M1 (0.125 g), BCS (7.83 g) and PB (7.83 g) were added and stirred at 25 ° C. for 6 hours to obtain a liquid crystal aligning agent (8). Got. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 9>
NEP (25.5 g) was added to the polyimide powder (9) (2.50 g) obtained in Synthesis Example 9, and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S1 (0.30 g), BCS (5.88 g) and PB (7.83 g) were added and stirred at 25 ° C. for 6 hours to obtain a liquid crystal aligning agent (9). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 10>
NEP (23.5 g) was added to the polyimide powder (10) (2.50 g) obtained in Synthesis Example 10, and dissolved by stirring at 70 ° C. for 24 hours. S2 (0.125g) and PB (15.7g) were added to this solution, and it stirred at 25 degreeC for 6 hours, and obtained the 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.

<Example 11>
NEP (16.5 g) and γ-BL (4.14 g) were added to the polyimide powder (11) (1.50 g) obtained in Synthesis Example 11, and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S1 (0.105 g), BCS (8.27 g) and PB (12.4 g) were added and stirred at 25 ° C. for 6 hours 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.

<Example 12>
NMP (19.6 g) was added to the polyimide powder (12) (2.50 g) obtained in Synthesis Example 12, and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S1 (0.25 g), M1 (0.175 g), BCS (15.7 g) and DME (3.92 g) were added and stirred at 25 ° C. for 6 hours to obtain a liquid crystal aligning agent (12). Got. This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

<Example 13>
NEP (23.5 g) was added to the polyimide powder (13) (2.50 g) obtained in Synthesis Example 13, and dissolved by stirring at 70 ° C. for 24 hours. To this solution, S2 (0.175 g), BCS (7.83 g) and PB (7.83 g) were added and stirred at 25 ° C. for 6 hours 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.

<Comparative Example 1>
NMP (7.83 g) and γ-BL (23.5 g) were added to the polyimide powder (1) (2.50 g) obtained in Synthesis Example 1, and dissolved by stirring at 70 ° C. for 24 hours. BCS (7.83g) was added to this solution, and it stirred at 25 degreeC for 6 hours, and obtained the 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.

<Comparative example 2>
NEP (23.5 g) was added to the polyimide powder (3) (2.50 g) obtained in Synthesis Example 3, and dissolved by stirring at 70 ° C. for 24 hours. BCS (3.92g) and PB (11.8g) were added to this solution, and it stirred at 25 degreeC for 6 hours, and obtained the 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.

* 1: Indicates the amount (parts by mass) of the specific compound introduced relative to 100 parts by mass of the polyimide polymer.
* 2: Indicates the proportion of the polyimide polymer in the liquid crystal aligning agent.

* 1: Disturbance of liquid crystal alignment was observed in the vicinity of the sealant in the liquid crystal cell.
* 2: Disturbance of liquid crystal alignment was observed in the liquid crystal cell in a region having a width of 0.5 cm from the sealing agent (the width in which the disorder of liquid crystal alignment was observed is wider than * 1).

As can be seen from the above results, the liquid crystal aligning agent of the example of the present invention suppresses the decrease in the voltage holding ratio even when the liquid crystal cell is irradiated with ultraviolet rays, as compared with the liquid crystal aligning agent of the comparative example. I was able to. Further, even when the liquid crystal cell was stored in a high-temperature and high-humidity tank for a long time, no disorder in the liquid crystal alignment was observed in the vicinity of the sealant. That is, the liquid crystal aligning agent of the present invention suppresses a decrease in voltage holding ratio even after being exposed to light for a long time, and causes display unevenness in the vicinity of the frame of the liquid crystal display element under high temperature and high humidity conditions. It becomes a liquid crystal aligning film which can suppress generating.

Specifically, in the examples of the liquid crystal alignment treatment agent using the specific compound and the specific polyimide polymer in the present invention and the comparative example of the liquid crystal alignment treatment agent not using the specific compound, the liquid crystal alignment treatment agent of the comparative example Was inferior to the above characteristics. More specifically, it is a comparison between Example 1 and Comparative Example 1, and a comparison between Example 3 and Comparative Example 3.

In addition, the liquid crystal alignment treatment agent using the specific diamine compound (1) having the specific structure (1) in the present invention has a liquid crystal cell for a long time in the emphasis test as compared with the liquid crystal alignment treatment agent not using the liquid crystal alignment treatment agent. Even when stored in a high-temperature and high-humidity tank, the disorder of liquid crystal orientation was not observed in the vicinity of the sealant. More specifically, it is a comparison between Example 3 and Example 4 in the comparison under the same conditions in the enhancement test.

In addition, the liquid crystal aligning agent using the specific diamine compound (2) having the specific structure of the formula [3-1] among the specific structure (2) in the present invention is represented by the formula [3-2]. Compared to liquid crystal alignment treatment agents that use diamine compounds with a specific structure, in the emphasis test, even if the liquid crystal cell is stored in a high-temperature and high-humidity tank for a long time, disorder of the liquid crystal alignment is observed near the sealant. There wasn't. More specifically, it is a comparison between Example 5 and Example 6 in the comparison under the same conditions in the enhancement test.

The liquid crystal alignment treatment agent of the present invention suppresses a decrease in voltage holding ratio even after being exposed to light irradiation for a long time, and enhances the adhesion between the sealing agent and the liquid crystal alignment film, under high temperature and high humidity conditions. It is possible to provide a liquid crystal alignment film capable of suppressing the occurrence of display unevenness in the vicinity of the frame of the liquid crystal display element. In addition, the liquid crystal display element which has said liquid crystal aligning film, and the liquid-crystal aligning agent which can provide said liquid crystal aligning film can be provided.

Therefore, the liquid crystal display element having the liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention has excellent reliability, and can be suitably used for a large-screen, high-definition liquid crystal television, etc. It is useful for a device, a TFT liquid crystal device, particularly a vertical alignment type liquid crystal display device.

Furthermore, the liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention is also useful for a liquid crystal display element that needs to be irradiated with ultraviolet rays when producing a liquid crystal display element. That is, a liquid crystal composition comprising a liquid crystal layer between a pair of substrates provided with electrodes, and containing a polymerizable compound that is polymerized by at least one of active energy rays and heat between the pair of substrates, A liquid crystal display element manufactured through a step of polymerizing the polymerizable compound while applying a voltage between the electrodes, and further comprising a liquid crystal layer between a pair of substrates provided with electrodes, A liquid crystal produced by placing a liquid crystal alignment film containing a polymerizable group that polymerizes at least one of active energy rays and heat between substrates and polymerizing the polymerizable group while applying a voltage between the electrodes. This is particularly useful for display elements.

Claims

Liquid crystal aligning agent containing the following (A) component and (B) component.
(A) component: heteropolyacid.
Component (B): a polymer.
The liquid crystal aligning agent according to claim 1, wherein the heteropolyacid is at least one selected from the group consisting of phosphomolybdic acid, silicomolybdic acid, phosphotungstic acid, silicotungstic acid and phosphotungstomolybdic acid.
The liquid crystal aligning agent according to claim 1 or 2, wherein the polymer has a nitrogen-containing aromatic heterocycle.
The polymer is at least one selected from the group consisting of acrylic polymer, methacrylic polymer, novolak resin, polyhydroxystyrene, polyimide precursor, polyimide, polyamide, polyester, cellulose and polysiloxane. Liquid crystal aligning agent as described in any one of these.
The liquid crystal aligning agent according to claim 4, wherein the polymer is a polyimide precursor obtained by a reaction of a diamine component and a tetracarboxylic acid component or a polyimide obtained by imidizing the polyimide precursor.
The liquid-crystal aligning agent of Claim 5 in which the said diamine component contains the diamine compound which has a structure shown by following formula [2].

(W 1 is —O—, —NH—, —N (CH 3 ) —, —CONH—, —NHCO—, —CH 2 O—, —OCO—, —CON (CH 3 ) — and —N (CH 3 ) At least one linking group selected from the group consisting of CO—, wherein W 2 is at least one selected from the group consisting of a single bond, an alkylene group having 1 to 20 carbon atoms, a non-aromatic ring and an aromatic ring. W 3 represents a single bond, —O—, —NH—, —N (CH 3 ) —, —CONH—, —NHCO—, —COO—, —OCO—, —CON (CH 3 ) —, At least one selected from the group consisting of —N (CH 3 ) CO— and —O (CH 2 ) m — (m represents an integer of 1 to 5), W 4 represents a nitrogen-containing aromatic heterocyclic ring; Show.)
The liquid-crystal aligning agent of Claim 6 in which the said diamine component contains the diamine compound shown by following formula [2a].

(W represents the structure represented by the formula [2]. M1 represents an integer of 1 to 4.)
The liquid crystal alignment treatment agent according to any one of claims 5 to 7, wherein the diamine component includes a diamine compound having a structure represented by the following formula [3-1] or formula [3-2].

(Y 1 is a single bond, — (CH 2 ) a — (a is an integer of 1 to 15), —O—, —CH 2 O—, —CONH—, —NHCO—, —CON (CH 3 ) —, —N (CH 3 ) CO—, —COO—, and —OCO— represent at least one linking group selected from the group consisting of Y 2 is a single bond or — (CH 2 ) b — (b is 1 Y 3 is a single bond, — (CH 2 ) c — (c is an integer of 1 to 15), —O—, —CH 2 O—, —COO— and —. Y 4 represents at least one selected from the group consisting of OCO—, wherein Y 4 has at least one divalent cyclic group selected from the group consisting of a benzene ring, a cyclohexane ring and a heterocyclic ring, or a carbon number of 17 to 17 having a steroid skeleton. 51 represents a divalent organic group, and an arbitrary hydrogen atom on the cyclic group has 1 carbon atom. 3 alkyl group, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, good .Y 5 be substituted with a fluorine-containing alkoxyl group or a fluorine atom having 1 to 3 carbon atoms benzene At least one cyclic group selected from the group consisting of a ring, a cyclohexane ring and a heterocyclic ring, wherein any hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms or an alkoxyl having 1 to 3 carbon atoms Group, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom, n represents an integer of 0 to 4. Y 6 represents 1 carbon atom. An alkyl group having 1 to 18 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, and a fluorine-containing alkoxyl group having 1 to 18 carbon atoms. At least one selected from the group of

(Y 7 is a single bond, —O—, —CH 2 O—, —CONH—, —NHCO—, —CON (CH 3 ) —, —N (CH 3 ) CO—, —COO— and —OCO—. And at least one linking group selected from the group consisting of Y 8 represents an alkyl group having 8 to 18 carbon atoms or a fluorine-containing alkyl group having 6 to 18 carbon atoms.)
The liquid crystal aligning agent according to claim 8, wherein the diamine compound is represented by the following formula [3a].

(Y represents the structure represented by Formula [3-1] or Formula [3-2]. N1 represents an integer of 1 to 4.)
The liquid crystal aligning agent according to any one of claims 5 to 9, wherein the tetracarboxylic acid component contains a tetracarboxylic dianhydride represented by the following formula [4].

(Z represents at least one structure selected from the group consisting of structures represented by the following formulas [4a] to [4k].)

(Z 1 to Z 4 each independently represents at least one selected from the group consisting of a hydrogen atom, a methyl group, a chlorine atom and a benzene ring. Z 5 and Z 6 each independently represent a hydrogen atom or methyl Group.)
The liquid crystal alignment treatment agent contains at least one solvent selected from the group consisting of N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and γ-butyrolactone. The liquid crystal aligning agent according to one item.
The liquid crystal aligning agent is 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, dipropylene glycol dimethyl ether, and the following formula [D1] to The liquid crystal aligning agent according to any one of claims 1 to 11, comprising at least one solvent selected from the group consisting of solvents represented by the formula [D3].

(D 1 represents an alkyl group having 1 to 3 carbon atoms. D 2 represents an alkyl group having 1 to 3 carbon atoms. D 3 represents an alkyl group having 1 to 4 carbon atoms.)
The liquid crystal aligning agent is selected from the group consisting of a crosslinkable compound selected from the group consisting of an epoxy group, an isocyanate group, an oxetane group and a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group and an alkoxyalkyl group having 1 to 3 carbon atoms. The liquid crystal aligning agent according to any one of claims 1 to 12, comprising a crosslinkable compound or a crosslinkable compound having a polymerizable unsaturated bond group.
A liquid crystal alignment film obtained from the liquid crystal alignment treatment agent according to any one of claims 1 to 13. *
A liquid crystal alignment film obtained by applying the liquid crystal alignment treatment agent according to any one of claims 1 to 13 by an inkjet method.
A liquid crystal display element having the liquid crystal alignment film according to claim 14 or 15.
A liquid crystal composition comprising a liquid crystal layer between a pair of substrates provided with electrodes and comprising a polymerizable compound that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates, and the electrodes The liquid crystal alignment film according to claim 14 or 15, wherein the liquid crystal alignment film is used for a liquid crystal display device produced through a step of polymerizing the polymerizable compound while applying a voltage therebetween.
A liquid crystal display element comprising the liquid crystal alignment film according to claim 17.
A liquid crystal layer between a pair of substrates provided with electrodes, and a liquid crystal alignment film containing a polymerizable group that is polymerized by at least one of active energy rays and heat between the pair of substrates; 16. The liquid crystal alignment film according to claim 14, wherein the liquid crystal alignment film is used for a liquid crystal display device produced through a step of polymerizing the polymerizable group while applying a voltage therebetween.
A liquid crystal display element comprising the liquid crystal alignment film according to claim 19.