WO2013008852A1 - Composition, liquid crystal alignment treatment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

Provided are: a composition for use in the formation of a film, particularly a liquid crystal alignment treatment agent for use in the formation of a liquid crystal alignment film; a liquid crystal alignment film produced using the composition or the liquid crystal alignment treatment agent; and a liquid crystal display element. A composition comprising: a polyimide precursor that is produced by reacting a diamine component comprising a diamine compound having a carboxyl group with a tetracarboxylic acid component and/or a polyimide that is produced by imidizing the polyimide precursor; and a compound represented by formula [1] (wherein R₁ represents an alkyl group having 1 to 4 carbon atoms).

Description

Composition, liquid crystal alignment treatment agent, liquid crystal alignment film, and liquid crystal display element

The present invention relates to a composition used for forming a film, in particular, a liquid crystal alignment treatment agent used for forming a liquid crystal alignment film, a liquid crystal alignment film to be obtained, and a liquid crystal display element using the liquid crystal alignment film.

A film made of an organic material such as a polymer material has been widely used as an interlayer insulating film, a protective film, and the like in electronic devices because of its ease of formation and insulation performance. In a liquid crystal display element well known as a display device, an organic film made of an organic material is used as a liquid crystal alignment film.

The liquid crystal alignment film is a constituent member of a liquid crystal display element that is widely used as a display device. The liquid crystal alignment film is formed on the surface of a substrate that sandwiches the liquid crystal and plays a role of aligning the liquid crystal in a certain direction. Further, the liquid crystal alignment film has a role of controlling the pretilt angle of the liquid crystal in addition to the role of aligning the liquid crystal.
In recent years, liquid crystal display elements have become highly functional, and the range of use has been expanded. The liquid crystal alignment film has performance and reliability for suppressing display defects of the liquid crystal display elements and realizing high display quality. It has been demanded.

Currently, as a main liquid crystal alignment film used industrially, a polyimide organic film which is excellent in durability and suitable for controlling the pretilt angle of liquid crystal is widely used. The liquid crystal alignment film made of this polyimide organic film is formed from a liquid crystal alignment treatment agent that is a composition containing a polyimide precursor polyamic acid (polyamic acid) and / or a polyimide solution imidized with polyamic acid. . That is, the polyimide-based liquid crystal alignment film is formed by applying a liquid crystal alignment treatment agent composed of a polyimide solution or a polyamic acid solution that is a polyimide precursor to a substrate and firing at a temperature of about 250 ° C. (For example, refer to Patent Document 1).

Japanese Unexamined Patent Publication No. 09-278724

The polyimide-based liquid crystal alignment film is formed by applying a liquid crystal alignment treatment agent comprising a polyimide solution or a polyamic acid solution of a polyimide precursor to a substrate, and then baking the coating film. There is a demand for improvement in coating properties, in particular, improvement in wettability and spreadability to a substrate. By improving the wetting and spreading property, defects such as repellency and pinholes during printing application can be suppressed in the application process in the process of forming the liquid crystal alignment film.

Polyimide-based organic films are widely used for interlayer insulating films and protective films in electronic devices, and can be formed from a composition containing a polyimide precursor, a polyamic acid or a polyimide solution, and a liquid crystal As in the case of the alignment film, improvement in applicability is required. The improvement in coating properties is effective for suppressing defects during printing coating.

Accordingly, the present invention provides a composition capable of forming a polyimide-based organic film having improved coatability and high wettability to a substrate, particularly a liquid crystal capable of forming a liquid crystal alignment film in which defects such as repelling and pinholes are suppressed. An object is to provide an alignment treatment agent, a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent, and a liquid crystal display device including the liquid crystal alignment film.

The present invention has the following gist.
(1) A polyimide obtained by reacting a diamine component containing a diamine compound having a carboxyl group and a tetracarboxylic acid component and / or a polyimide obtained by imidizing the polyimide precursor, and a compound represented by the following formula [1] And a composition comprising:

(In the formula [1], R ₁ is an alkyl group having 1 to 4 carbon atoms.)
(2) The composition according to (1), wherein the compound represented by the formula [1] is a compound represented by the following formula [2] or the following formula [3].

(3) The composition according to (1) or (2), wherein the diamine compound having a carboxyl group is a diamine compound having a — (CH ₂ ) _a —COOH group (a is an integer of 0 to 4). object.
(4) The composition according to any one of (1) to (3), wherein the diamine compound having a carboxyl group is a diamine compound having a structure represented by the following formula [4].

(In the formula [4], a represents an integer of 0 to 4, and n represents an integer of 1 to 4.)
(5) The composition according to any one of (1) to (4), wherein the content of the diamine compound is 20 to 100 mol% in the diamine component.

(6) The composition according to any one of (1) to (5), wherein the diamine component includes a second diamine compound having a structure represented by the following formula [5].

(In the formula [5], X represents a — (CH ₂ ) _b —OH group (b is an integer of 0 to 4), a hydrocarbon group having 1 to 22 carbon atoms, and a hydrocarbon group having 1 to 6 carbon atoms. And a di-substituted amino group substituted by or a group represented by the following formula [6], and n represents an integer of 1 to 4.)

(In formula [6], Y ¹ is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. Y ² is a single bond or (CH ₂ ) _b — (b is an integer of 1 to 15) Y ³ is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15) ), —O—, —CH ₂ O—, —COO— or OCO— Y ⁴ is a divalent cyclic group selected from a benzene ring, a cyclohexyl ring and a heterocyclic ring (on these cyclic groups) The optional hydrogen atom is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. it may be substituted), or a divalent organic group having a carbon number of 12 to 25 having a steroid skeleton .Y ⁵ A divalent cyclic group selected from a benzene ring, a cyclohexyl ring and a heterocyclic ring (an arbitrary hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, carbon Y ⁶ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, a carbon atom, which may be substituted with a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. A fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms, n represents an integer of 0 to 4.)

(7) The composition according to any one of (1) to (6), wherein the tetracarboxylic dianhydride is a compound represented by the following formula [7].

(In Formula [7], Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms and contains a non-aromatic cyclic hydrocarbon group having 4 to 10 carbon atoms.)
(8) The composition according to (7), wherein Z ₁ is a structure represented by the following formulas [7a] to [7j].

(In the formula [7a], Z ₂ to Z ₅ are a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, which may be the same or different. In the formula [7g], Z ₆ and Z ₇ Are hydrogen atoms or methyl groups, which may be the same or different.

(9) A liquid crystal aligning agent comprising the composition according to any one of (1) to (8).
(10) A liquid crystal alignment film obtained from the liquid crystal aligning agent according to (9).
(11) A liquid crystal alignment film obtained by an ink jet method using the liquid crystal alignment treatment agent according to (9).
(12) 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 (10) or (11), wherein the liquid crystal alignment film is used for a liquid crystal display device manufactured through a step of polymerizing the polymerizable compound while applying a voltage between the electrodes.
(13) A liquid crystal display device having the liquid crystal alignment film according to (10) or (11).
(14) A polymerizable compound having a liquid crystal layer between a pair of substrates provided with an electrode and the liquid crystal alignment film, and polymerized by at least one of active energy rays and heat between the pair of substrates. The liquid crystal display element according to (13), wherein the liquid crystal display element is manufactured through a process of disposing a liquid crystal composition and polymerizing the polymerizable compound while applying a voltage between the electrodes.

ADVANTAGE OF THE INVENTION According to this invention, the composition which can form the polyimide-type film | membrane excellent in applicability | paintability is provided. In particular, there is provided a liquid crystal aligning agent that can form a liquid crystal alignment film excellent in applicability and having suppressed defects such as repellency and pinholes.
A liquid crystal alignment film obtained by using the liquid crystal alignment treatment agent of the present invention can be formed without defects, and a liquid crystal display element having such a liquid crystal alignment film has high characteristics and reliability.

As described above, a polyimide film, particularly a polyimide liquid crystal alignment film is formed by using a polyimide solution obtained by dissolving polyimide or a polyimide precursor in a solvent, or a polyimide precursor solution. Then, it is applied to the substrate and is usually performed by baking at a temperature of about 200 to 300 ° C.
When polyamic acid, which is a polyimide precursor, is used for forming the polyimide liquid crystal alignment film, dehydration ring closure reaction (thermal imidization) of the polyamic acid is performed by heating.
On the other hand, when a polyimide-based liquid crystal alignment film is formed using a polyimide solution, the main purpose of the firing step is to remove the solvent from the coating film.

Therefore, although the heating temperature in the case of using a polyimide solution is influenced by the boiling point of the solvent to be used, it can usually be made lower than in the case of using polyamic acid.
When preparing a polyimide solution in order to form a polyimide-based liquid crystal alignment film, it is necessary to dissolve a polyimide that is normally difficult to dissolve, and therefore, an appropriate solvent must be used. For conventional polyimide, a highly polar solvent such as N-methyl-2-pyrrolidone (hereinafter referred to as NMP) is selected and used. A highly polar solvent has a high surface tension as a characteristic, and NMP also has a high surface tension characteristic. Therefore, when a polyimide solution using NMP as a solvent is used and applied to a substrate, the wetting and spreading characteristics on the substrate are not good. As a result, defects in printing and coating such as repellency and pinholes occur in the coating film, and it may be difficult to form a high-quality liquid crystal alignment film with uniform characteristics.

If the polyimide solution can be prepared using a solvent having a lower surface tension, the coating property of the polyimide solution to the substrate will be good, and the occurrence of defects during printing application such as repellency and pinholes can be suppressed. it can.
That is, if a solvent having a lower surface tension characteristic is selected, and a polyimide solution can be prepared by dissolving polyimide, good coating characteristics can be realized. Such an improvement in coatability is also required in the formation of polyimide films such as insulating films and protective films for electronic devices. Improvement in applicability enables formation of a more uniform polyimide film with fewer defects such as repellency and pinholes that occur during printing application.

It was found that, in order to form a polyimide film, particularly a polyimide liquid crystal alignment film, it is necessary to improve the solubility of polyimide in a solvent and to select a solvent. It is desirable that the selected solvent has a lower surface tension characteristic in consideration of applicability. In that case, it is also necessary to select a polyimide structure corresponding to the solubility of the solvent.

By using a diamine compound having a specific structure, the present inventor can obtain a polyimide precursor having a specific structure. By imidizing this polyimide precursor, a polyimide having improved solubility can be obtained. I found it. In addition, a low surface tension compound (also referred to as a solvent) that dissolves the polyimide was found.
That is, in this invention, the composition which melt | dissolved the polyimide of the specific structure in the specific solvent can be obtained, and a liquid-crystal aligning agent can be comprised. Moreover, the liquid-crystal aligning agent obtained from the obtained composition is excellent in applicability | paintability, and is suitable for forming a liquid crystal aligning film. The obtained liquid crystal alignment film is suitable for providing a highly reliable liquid crystal display element.

The composition of the present invention contains a polyimide obtained by dehydrating and ring-closing a polyimide precursor. This composition can particularly constitute a liquid crystal alignment treatment agent.

The composition of the present invention includes a polyimide precursor obtained by (polycondensation) reaction of a diamine component containing a carboxyl group-containing diamine compound and a tetracarboxylic acid component, and / or a polyimide obtained by imidizing the polyimide precursor, And a compound represented by the following formula [1].

In the formula [1], R ₁ is an alkyl group having 1 to 4 carbon atoms.

The compound represented by the above formula [1] is preferably a compound represented by the following formula [2] or the following formula [3]. The compound represented by the formula [1] is preferably contained as a solvent in the composition.

It is preferable that the diamine component which forms a polyimide precursor contains the diamine compound which has a carboxyl group of following formula [4]. In addition, it is possible to contain a second diamine compound. As the second diamine compound, a diamine compound having a structure represented by the following formula [5] is preferable.

In the formula [4], a represents an integer of 0 to 4, and n represents an integer of 1 to 4.

In the formula [5], X represents a — (CH ₂ ) _b —OH group (b is an integer of 0 to 4), a hydrocarbon group having 1 to 22 carbon atoms, and a hydrocarbon group having 1 to 6 carbon atoms. A substituted di-substituted amino group or a group represented by the following formula [6], and n represents an integer of 0 to 4.

In the formula [6], Y ¹ is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. Y ² is a single bond or (CH ₂ ) _b — (b is an integer of 1 to 15). Y ³ is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. Y ⁴ represents a divalent cyclic group selected from a benzene ring, a cyclohexyl ring, and a heterocyclic ring (an arbitrary hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, an alkyl group having 1 to 3 carbon atoms) An alkoxyl 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, which may be substituted with a fluorine atom), or a divalent group having 12 to 25 carbon atoms having a steroid skeleton Is an organic group. Y ⁵ represents a divalent cyclic group selected from a benzene ring, a cyclohexyl ring and a heterocyclic ring (an arbitrary hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms) Or 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. Y ⁶ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms. n represents an integer of 0 to 4.

<Diamine compound having a carboxyl group>
The diamine compound having a carboxyl group for obtaining the polyimide precursor of the present invention is a diamine compound having — (CH ₂ ) _a —COOH group (a is an integer of 0 to 4) in the molecule. preferable.
For example, the diamine compound of the structure shown by following formula [4] can be mentioned.

In the formula [4], a represents an integer of 0 to 4, and n represents an integer of 1 to 4.

Furthermore, diamine compounds having a carboxyl group in the molecule represented by the following formulas [4-1] to [4-4] can be exemplified.

In the formula [4-1], A ₄ represents a single bond, —CH ₂ —, —C ₂ H ₄ —, —C (CH ₃ ) ₂ —, —CF ₂ —, —C (CF ₃ ) —, — O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —OCH ₂ —, —COO—, —OCO—, —CON (CH ₃ )-or N (CH ₃ ) CO-, m ₂ and m ₃ are each an integer of 0 to 4, and m ₂ + m ₃ is an integer of 1 to 4.
In the formula [4-2], m ₄ and m ₅ are each an integer of 1 to 5.
In the formula [4-3], A ₅ is a linear or branched alkyl group having 1 to 5 carbon atoms, and m ₆ is an integer of 1 to 5.

In the formula [4-4], A ₆ represents a single bond, —CH ₂ —, —C ₂ H ₄ —, —C (CH ₃ ) ₂ —, —CF ₂ —, —C (CF ₃ ) —, — O—, —CO—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —OCH ₂ —, —COO—, —OCO—, —CON (CH ₃ ) — or N (CH ₃ ) CO—, and m ₇ is an integer of 1 to 4.

The amount of the diamine compound having a carboxyl group is preferably 10 to 100 mol%, more preferably 20 to 100 mol%, based on the total diamine component.
The diamine compound having the above carboxyl group is soluble in a solvent when used as a composition, coating properties, liquid crystal orientation in the case of a liquid crystal alignment film, voltage holding ratio, accumulated charge, etc. One type or a mixture of two or more types can also be used.

<Synthesis Method of Diamine Compound>
Although the method to manufacture the diamine compound shown by Formula [4] is not specifically limited, What is shown below is mentioned as a preferable method.
For example, the diamine compound represented by the formula [4] can be obtained by synthesizing a dinitro compound represented by the following formula [4A], further reducing the nitro group and converting it to an amino group.

(In the formula [4A], a represents an integer of 0 to 4, and n represents an integer of 1 to 4.)

The method for reducing the dinitro group is not particularly limited, and usually palladium-carbon, platinum oxide, Raney nickel, platinum black, rhodium-alumina, platinum sulfide carbon, etc. are used as a catalyst, ethyl acetate, toluene, tetrahydrofuran, dioxane, There is a method in which hydrogen gas, hydrazine, hydrogen chloride, or the like is used in a solvent such as an alcohol solvent.

<Second diamine compound>
The diamine component contained in the composition of the present invention can contain a diamine compound represented by the following formula [5] as the second diamine compound.

In formula [5], X is a substituent. n represents an integer of 0 to 4.

Specifically, in the formula [5], X is a — (CH ₂ ) _b —OH group (b is an integer of 0 to 4), a hydrocarbon group having 1 to 22 carbon atoms, and 1 to 6 carbon atoms. Or a group represented by the following formula [6].

In the formula [6], Y ¹ is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. Among them, a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O— or COO— is from the viewpoint of facilitating the synthesis of the side chain structure. A single bond, — (CH ₂ ) _a — (a is an integer of 1 to 10), —O—, —CH ₂ O— or COO— is more preferable.

In the formula [6], Y ² is a single bond or (CH ₂ ) _b — (b is an integer of 1 to 15). Among these, a single bond or (CH ₂ ) _b — (b is an integer of 1 to 10) is preferable.
In the formula [6], Y ³ is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. Among them, a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO— facilitates the synthesis of the side chain structure. From the standpoint of the above, a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 10), —O—, —CH ₂ O—, —COO— or OCO— is more preferred.

In the formula [6], Y ⁴ represents a divalent cyclic group selected from the group consisting of a benzene ring, a cyclohexane ring and a heterocyclic ring (an arbitrary hydrogen atom on these cyclic groups is an alkyl having 1 to 3 carbon atoms). Group, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom), or a carbon having a steroid skeleton It is a divalent organic group of several 12 to 25. Of these, a divalent cyclic group selected from the group consisting of a benzene ring and a cyclohexane ring or a divalent organic group having 12 to 25 carbon atoms and having a steroid skeleton is preferable.

In the formula [6], Y ⁵ is a divalent cyclic group selected from the group consisting of a benzene ring, a cyclohexane ring, and a heterocyclic ring, and any hydrogen atom on these cyclic groups has 1 to It may be substituted with a 3 alkyl group, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom.
In the formula [6], n is an integer of 0 to 4. Preferably, it is an integer of 0-2.

In the formula [6], Y ⁶ is an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms. . Among these, an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 10 carbon atoms is preferable. More preferably, it is an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms. More preferred is an alkyl group having 1 to 9 carbon atoms or an alkoxyl group having 1 to 9 carbon atoms.
As a preferred combination of Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ , Y ⁶ and n in the formula [6] constituting the substituent X of the formula [5], International Publication No. WO2011-132751 (2011 The same combinations as those described in (2-1) to (2-629) listed in Tables 6 to 47 on pages 13 to 34 of. 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 .

Specific examples of the second diamine compound having the structure represented by the formula [5] are given below, but these are not limited to the examples.

That is, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,6-diaminotoluene, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4 In addition to -diaminobenzyl alcohol and 4,6-diaminoresorcinol, diamine compounds having structures represented by the following formulas [5-1] to [5-41] can be given.

(In the formulas [5-1] to [5-4], A ₁ is an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group.)

(In the formulas [5-29] to [5-31], R ₁ represents —O—, —OCH ₂ —, —CH ₂ O—, —COOCH ₂ —, or CH ₂ OCO—, and R ₂ represents the number of carbon atoms. 1 to 22 alkyl groups, alkoxy groups, fluorine-containing alkyl groups or fluorine-containing alkoxy groups.)

(In the formulas [5-32] to [5-34], R ₃ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ — or CH _2. R ₄ is an alkyl group having 1 to 22 carbon atoms, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group.

(In Formula [5-35] and Formula [5-36], R ₅ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ —, — CH ₂ — or O—, and R ₆ is a fluorine group, cyano group, trifluoromethane group, nitro group, azo group, formyl group, acetyl group, acetoxy group or hydroxyl group.

(In Formula [5-37] and Formula [5-38], R ₇ is an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomerism of 1,4-cyclohexylene is a trans isomer. )

(In Formula [5-39] and Formula [5-40], R ₈ is an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomerism of 1,4-cyclohexylene is a trans isomer. .)

(In the formula [5-41], B ₄ is an alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, and B ₃ is a 1,4-cyclohexylene group or a 1,4-phenylene group. B ₂ is an oxygen atom or COO- * (where a bond marked with "*" is bonded to B ₃ ), and B ₁ is an oxygen atom or COO- * (where "*" is The bond attached is bonded to (CH ₂ ) a ₂ ). A ₁ is an integer of 0 or 1, a ₂ is an integer of 2 to 10, and a ₃ is an integer of 0 or 1. )

The second diamine compound has one kind according to the characteristics such as solubility in a solvent and coating property when it is made into a composition, liquid crystal orientation when it is made into a liquid crystal alignment film, voltage holding ratio, accumulated charge and the like. Alternatively, two or more types can be mixed and used.

<Synthesis Method of Second Diamine Compound>
Although the method to manufacture the diamine compound shown by Formula [5] is not specifically limited, What is shown below is mentioned as a preferable method.

For example, the diamine compound represented by the formula [5] can be obtained by synthesizing a dinitro compound represented by the following formula [5A], further reducing the nitro group and converting it to an amino group.

The method for reducing the dinitro group is not particularly limited, and usually palladium-carbon, platinum oxide, Raney nickel, platinum black, rhodium-alumina, platinum sulfide carbon, etc. are used as a catalyst, ethyl acetate, toluene, tetrahydrofuran, dioxane, There is a method in which hydrogen gas, hydrazine, hydrogen chloride, or the like is used in a solvent such as an alcohol solvent. In addition, X and n in Formula [5A] are the same meaning as the definition in Formula [5] in the above-mentioned 2nd diamine compound.

<Other diamine compounds>
As long as the effects of the present invention are not impaired, a diamine compound having a carboxyl group in the molecule or a diamine compound having another structure (other diamine compounds) in addition to the second diamine compound having the structure represented by the formula [5] Can also be used. It is good also as a liquid-crystal aligning agent by preparing the composition containing the polyimide obtained after using together these to obtain a polyimide precursor, and making the obtained polyimide.

Specific examples of other diamine compounds are listed below.
Examples of other diamine compounds include p-phenylenediamine, 4,4′-diaminobiphenyl, 3,3′-dimethyl-4,4′-diaminobiphenyl, and 3,3′-dimethoxy-4,4′-diamino. Biphenyl, 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'-diaminodiphe Nylmethane, 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'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3 ' -Diaminodiphenylamine, N-methyl (4,4'-diaminodi Enyl) amine, N-methyl (3,3′-diaminodiphenyl) amine, N-methyl (3,4′-diaminodiphenyl) amine, N-methyl (2,2′-diaminodiphenyl) amine, N-methyl ( 2,3′-diaminodiphenyl) amine, 4,4′-diaminobenzophenone, 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2′-diaminobenzophenone, 2, , 3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6 diaminonaphthalene, 2, 7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-aminophenyl) ethane 1,2-bis (3-aminophenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (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, 1,4-bis (4-aminophenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (4-aminobenzyl) benzene, 1,3-bis ( 4-Aminophenoxy) benzene, 4,4 ′-[1,4-phenylenebis (methylene)] dianiline, 4,4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,4 ′-[1 , 4-fe Nylenebis (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-aminophenoxy) ) Terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N, N ′-(1,4-phenylene) bis (4-aminobenzamide) ), N, N ′-(1,3-phenylene) bis (4-aminobenzamide), N, N ′-(1,4-phenylene) bis (3-aminobenzamide), N, N ′-(1, 3-phenylene) bis (3-aminobenzamide), N, N′-bis (4-aminophenyl) terephthalamide, N, N′-bis (3-aminophenyl) terephthalamide, N, N′-bis (4 -Aminophenyl) isophthalamide, N, N'-bis (3-aminophenyl) isophthalamide, 9,10-bis (4-aminophenyl) anthracene, 4,4'- (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) hexafluoro Propane, 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-bi (3-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1, 6-bis (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- (3-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,8-bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10- (4-aminophenoxy) decane 1,10- (3-aminophenoxy) decane, 1,11- (4-aminophenoxy) undecane, 1,11- (3-aminophenoxy) undecane, Aromatic diamines such as 2- (4-aminophenoxy) dodecane and 1,12- (3-aminophenoxy) dodecane; bis (4-aminocyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) methane and the like 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1, And aliphatic diamines such as 9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

Examples of other diamine compounds include those having an alkyl group, a fluorine-containing alkyl group, an aromatic ring, an aliphatic ring or a heterocyclic ring in the diamine side chain, and those having a macrocyclic substituent composed of these. it can. Specifically, diamine compounds represented by the following formulas [DA1] to [DA13] can be exemplified.

(Wherein _{[DA1] ~ [DA6],} A 2 is -COO -, - OCO -, - CONH -, - NHCO -, - CH 2 -, - O -, - CO- or a NH-, _{A 3} Represents a linear or branched alkyl group having 1 to 22 carbon atoms, or a linear or branched fluorine-containing alkyl group having 1 to 22 carbon atoms.

(In the formula [DA7], p is an integer of 1 to 10.)

As long as the effects of the present invention are not impaired, diamine compounds represented by the following formulas [DA8] to [DA13] can also be used.

(In the formula [DA10], m is an integer of 0 to 3, and in the formula [DA13], n is an integer of 1 to 5.)

Furthermore, diamine compounds represented by the following formula [DA14] and formula [DA15] can also be used.

The above-mentioned other diamine compounds are important in the liquid crystal alignment film, such as the solubility and coating properties in the solvent when the composition is formed, the alignment of the liquid crystal when the liquid crystal alignment film is formed, the voltage holding ratio, and the accumulated charge. Depending on the characteristics, one kind or a mixture of two or more kinds may be used.

<Tetracarboxylic acid component>
In order to obtain the polyimide precursor of the present invention, a tetracarboxylic dianhydride having an alicyclic structure represented by the following formula [7] (also referred to as a specific tetracarboxylic dianhydride) is part of the tetracarboxylic acid component. It is preferable to use as.

In the formula [7], Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms and contains a non-aromatic cyclic hydrocarbon group having 4 to 10 carbon atoms. Specifically, groups represented by the following formulas [7a] to [7j] are preferable.

In the formula [7a], Z ₂ to Z ₅ are a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, and may be the same or different.
In the formula [7g], Z ₆ and Z ₇ are a hydrogen atom or a methyl group, and may be the same or different.

In the formula [7], a preferable group of Z ₁ is preferably represented by the formula [7a], the formula [7c], the formula [7d], the formula [7e], the formula [7f] or the formula [7] because of polymerization reactivity and ease of synthesis. 7g]. Among these, a group represented by the formula [7a], the formula [7e], the formula [7f] or the formula [7g] is preferable, and the formula [7e] or the formula [7f] is most preferable.
When the tetracarboxylic dianhydride having the structure of the formula [7f] is used, the desired effect can be obtained by setting it to 20% by mass or more of the total components of the tetracarboxylic dianhydride. More preferably, it is 30 mass% or more. All of the tetracarboxylic acid components used for the polyimide synthesis may be tetracarboxylic dianhydrides having the structure of the formula [7f].

As long as the effects of the present invention are not impaired, other tetracarboxylic acid components other than the specific tetracarboxylic dianhydride can be used.
Other tetracarboxylic acid components include tetracarboxylic acid, tetracarboxylic acid dihalide, tetracarboxylic dianhydride, esterified product obtained by dialkyl esterifying the carboxylic acid group of tetracarboxylic acid, and dialkyl carboxylic acid group of tetracarboxylic acid dihalide. Examples include esterified esterified products.
Specific examples thereof include, 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, 1,3-diphenyl-1,2,3 Examples include 4-cyclobutanetetracarboxylic acid.

The above-mentioned other tetracarboxylic acid components can be used by selecting one type or two or more types in consideration of characteristics such as liquid crystal alignment properties, voltage holding characteristics and accumulated charges of the liquid crystal alignment film to be formed.

<Specific polymer and solvent>
The specific polymer of the present invention refers to a polyimide precursor (polyamide acid) obtained by reacting a diamine component containing a carboxyl group-containing diamine compound and a tetracarboxylic acid component and / or dehydrating and ring-closing the polyimide precursor. It is a polymer made of the resulting polyimide.
The polyimide precursor of the present invention has a structure represented by the following formula [A].

(In the formula [A], R ₁ is a tetravalent organic group, R ₂ is a divalent organic group, A ₁ and A ₂ are a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, They may be the same or different, and n represents a positive integer).

The reason why the specific polymer of the present invention can be obtained relatively easily by using a diamine component represented by the following formula [B] and a tetracarboxylic dianhydride represented by the following formula [C] as raw materials. Therefore, a polyimide obtained by imidizing a polyamic acid having a structural formula of a repeating unit represented by the following formula [D] is preferable.

(In formula [B] and formula [C], R ₁ and R ₂ are as defined in formula [A]).

(In formula [B] and formula [C], R ₁ and R ₂ are as defined in formula [A]).

Although the method for synthesizing the specific polymer is not particularly limited, it is usually obtained by reacting a diamine component and a tetracarboxylic acid component as described above. Therefore, the polyimide obtained from a polyimide precursor is prepared from the polyimide precursor obtained by making a diamine component and a tetracarboxylic acid component react.
Generally, at least one tetracarboxylic acid component selected from the group consisting of tetracarboxylic acids and derivatives thereof is reacted with a diamine component consisting of one or more diamine compounds to obtain a polyamic acid. Specifically, a method of obtaining polyamic acid by polycondensation of tetracarboxylic dianhydride and a diamine component, a method of obtaining polyamic acid by dehydration polycondensation reaction of tetracarboxylic acid and a diamine component, or tetracarboxylic acid dihalide A method is used in which a polyamic acid is obtained by polycondensation of a diamine component and diamine component.

Polyamide acid alkyl ester can be obtained by polycondensation of carboxylic acid group with dialkyl esterified tetracarboxylic acid and diamine component, tetracarboxylic acid dihalide with carboxylic acid group dialkylesterified and diamine component. A method 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 specific polymer of the present invention is obtained by reacting a diamine component containing a diamine compound having a carboxyl group in the molecule with a tetracarboxylic acid component having the above alicyclic structure, and further, the obtained polyimide precursor It is obtained by imidizing the body.
The specific polymer obtained from the diamine component and the tetracarboxylic acid component has improved solubility in a solvent. Furthermore, the applicability | paintability of the composition containing a specific solvent improves.

In order to obtain the specific polymer of the present invention, it is preferable to use a diamine compound having the structure represented by the above formula [4], and the amount used is 10 to 100 of the total diamine component used in the reaction for obtaining polyimide. The mol% is preferable, and more preferably 20 to 100 mol%.

When the diamine component having the structure represented by the above formula [5] is contained in the diamine component used for obtaining the specific polymer of the present invention, the amount used is 90 of the total diamine component used for the reaction for obtaining the specific polymer. It is preferably at most mol%, more preferably at most 80 mol%. In that case, it is preferable to set it as 20 mol% or more from the relationship with the preferable usage-amount of the diamine compound which has a carboxyl group in a molecule | numerator.

In order to obtain the specific polymer of the present invention, a polyamic acid can be obtained by a reaction of a diamine component and a tetracarboxylic acid component using a known synthesis method, and then a polyimide can be obtained. As a method for obtaining the polyamic acid, for example, a method of reacting a diamine component and a tetracarboxylic acid component in an organic solvent is possible. This method is preferable in that the reaction proceeds relatively efficiently in an organic solvent and generation of by-products is small.

After synthesizing a polyimide precursor in an appropriate organic solvent to be described later and performing a dehydration ring-closing reaction to obtain a polyimide, the polyimide is separated, and at least one selected from the group consisting of compounds represented by the above formula [1] The composition of the present invention can be obtained by dissolving in a solvent containing a seed compound.

The organic solvent used for the reaction between the diamine component and the tetracarboxylic acid component is not particularly limited as long as the generated polyimide precursor is soluble.
Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclohexane Examples include pentanone and 4-hydroxy-4-methyl-2-pentanone.
These may be used alone or in combination. Moreover, even if it is a solvent which does not dissolve a polyimide precursor, if it is a range in which the produced | generated polyimide precursor does not precipitate, it can also be mixed and used for the said organic solvent. In addition, since the water | moisture content in an organic solvent inhibits a polymerization reaction and causes the produced | generated 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 dispersed or dissolved in the organic solvent as it is. Thus, it is possible to use a method of adding. Conversely, a method of adding a diamine component to a solution in which a tetracarboxylic acid component is dispersed or dissolved in an organic solvent, a method of alternately adding a tetracarboxylic acid component and a diamine component, and the like can also be mentioned. Any of these methods may be used in the present invention. In addition, when the diamine component or tetracarboxylic acid component is composed of a plurality of types of compounds, they may be reacted in a premixed state, individually reacted sequentially, and further mixed individually with low molecular weight substances. It is good also as a high molecular weight body by making it react.

The temperature at which the diamine component and the tetracarboxylic acid component are reacted can be arbitrarily selected within the range of −20 to 150 ° C., but in view of the reaction efficiency, it may be set within the range of −5 to 100 ° C. preferable. Moreover, reaction can be performed by arbitrary density | concentrations. However, if the concentration is too low, it is difficult to obtain a high molecular weight polyimide precursor. On the other hand, if the concentration is too high, the viscosity of the reaction solution becomes too high and uniform stirring becomes difficult. Therefore, it is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. In addition, it is also possible to carry out at a high concentration at the initial stage of the reaction and then add an organic solvent.

In the polymerization reaction for obtaining the polyimide precursor, the ratio between the total number of moles of the diamine component and the total number of moles of the tetracarboxylic acid component is preferably 0.8 to 1.2. Similar to the normal polycondensation reaction, the closer the molar ratio is to 1.0, the higher the molecular weight of the polymer produced. Therefore, it is possible to determine the total molar ratio by appropriately selecting depending on the case.

As described above, the polyimide of the present invention is obtained by dehydrating and ring-closing a polyimide precursor. This polyimide is useful as a polymer for obtaining a liquid crystal alignment film.
In the polyimide of the present invention, the dehydration cyclization rate (imidation rate) of the polyimide precursor is not necessarily 100%, and is, for example, in the range of 35 to 95%, more preferably 45, depending on the application and purpose. It can be adjusted within a range of ˜80%.

Examples of the method for imidizing the polyimide precursor include thermal imidization in which the polyimide precursor solution is heated as it is, and catalyst 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 to 400 ° C., preferably 120 to 250 ° C. The imidization of the polyimide precursor is preferably performed while removing water generated by the imidization reaction from the reaction 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 the amidic acid group, and the amount of the acid anhydride is 1 to 50 mol times, preferably 3 to 30 mol times the amido group. 30 mole times.

Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine and the like. Of these, pyridine is preferable in that it has an appropriate basicity for proceeding with the reaction.
Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. Of these, acetic anhydride is preferred because it allows easy purification after completion of the reaction. The imidization rate by catalytic imidation can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

When recovering the produced polyimide from the reaction solution of polyimide, the reaction solution may be poured into a precipitation solvent and precipitated. Examples of the precipitation 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 that has been introduced into the precipitation solvent and precipitated can be collected 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 a solvent and the precipitate is recovered again by repeating the operation 2 to 10 times, impurities in the polymer can be reduced. Examples of the precipitation solvent at this time include the above-described precipitation solvents, 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 specific polymer contained in the composition of the present invention is GPC (Gel Permeation Chromatography) in consideration of the strength of the coating film obtained by using this, the workability during coating film formation, and the uniformity of the coating film. The weight average molecular weight measured by the method is preferably 5,000 to 1,000,000, and more preferably 10,000 to 150,000.

<Liquid crystal alignment agent>
The liquid crystal aligning agent of the present invention is a coating solution for forming a liquid crystal alignment film, which is composed of the above-described composition, and is a solution obtained by dissolving a polymer component for forming a polymer film in a solvent. Composition. The polymer component contains at least one polymer selected from the above-described specific polymer of the present invention. The content of the polymer component in the liquid crystal aligning agent is preferably 0.1 to 20% by mass, more preferably 1 to 15% by mass, and particularly preferably 2 to 10% by mass.

In the present invention, all of the polymer components contained in the liquid crystal aligning agent may be the specific polymer of the present invention. Moreover, polymers other than the specific polymer of this invention may be mixed. In that case, the content of the other polymer in the polymer component is 0.5 to 15% by mass, preferably 1 to 10% by mass.

Other polymers include polyimide precursors other than a specific polymer obtained by reacting a diamine component containing a diamine compound having a carboxyl group in the molecule and a tetracarboxylic acid component having an alicyclic structure, and / or Or the polyimide which imidized the polyimide precursor is mentioned.
Furthermore, polymers other than polyimide, specifically, acrylic polymer, methacrylic polymer, polystyrene, polyamide and the like can be mentioned.

In the liquid crystal aligning agent of this invention, the said specific polymer is contained in the state melt | dissolved in the solvent. As the solvent to be used, a solvent containing a compound that dissolves the polyimide that is the specific polymer of the present invention and has lower surface tension characteristics than NMP, for example, is preferable.
Specifically, it is preferable to use a solvent containing a compound represented by the following formula [1].

In the formula [1], R ₁ is an alkyl group having 1 to 4 carbon atoms.

Among these, the compound represented by the above formula [1] is preferably a compound represented by the following formula [2] or the following formula [3].

The compound represented by the above formula [1] may be one kind or a mixture of two or more kinds. By using the compound represented by the formula [1] as a solvent, it is possible to provide a liquid crystal aligning agent having excellent coatability.

In the liquid crystal aligning agent of the present invention, the content of the solvent is preferably 70 to 99% by mass from the viewpoint of forming a uniform film by coating. Content can be suitably changed with the film thickness of the target liquid crystal aligning film. As the solvent, any one of the compounds represented by the formula [1] or a mixture of a plurality of compounds represented by the compound represented by the formula [1] is used.
Furthermore, as a solvent in a liquid-crystal aligning agent, other organic solvents other than the compound shown by said Formula [1] can be mixed and contained in the range which does not interfere with an applicability | paintability improvement.

Specific examples of other organic solvents include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-imidazolidinone. Methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, and the like. These may be used alone or in combination.
When such other organic solvent is contained, the content thereof is 50% by mass or less, preferably 40% by mass or less, based on the total solvent. More preferably, it is 30 mass% or less.

The liquid crystal alignment treatment agent of the present invention is for the purpose of further improving the film thickness uniformity and surface smoothness of the film when the liquid crystal alignment treatment agent is applied, as long as the effects of the present invention are not impaired. The poor solvent can be contained.

Specific examples of the poor solvent include the following. For example, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, isopentyl alcohol, tert-pentyl alcohol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, 1-heptanol 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 1,2- Etanji 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentane Diol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2-hexanone, 2 Heptanone, 4-heptanone, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate , Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, 2- (methoxymethoxy) ethanol, ethylene glycol isopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol hexyl ether, 2- (hexyloxy) ethanol, Furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monomethyl ether Propylene glycol monoethyl ether, propylene glycol monobutyl ether, 1- (butoxyethoxy) propanol, propylene glycol monomethyl ether acetate, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, tripropylene glycol monomethyl ether , Ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoacetate, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2- (2-Ethoxyethoxy) ethyl Acetate, diethylene glycol acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether acetate, methyl pyruvate , Ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, 3-methoxypropionate Acid butyl, lactate methyl ester, lactate ethyl ester, lactate n-propyl ester, lactate n-butyl ester, lactate isoamyl ester and the like. These poor solvents may be used alone or in combination of two or more.

When such a poor solvent is contained, the content of the compound represented by the above formula [1] is 90% by mass or less, preferably 70% by mass or less in the total solvent. More preferably, it is 40 mass% or less.

Furthermore, the liquid crystal aligning agent of the present invention is a compound, liquid crystal aligning film and substrate for improving the film thickness uniformity and surface smoothness when the liquid crystal aligning agent is applied, as long as the effects of the present invention are not impaired. A compound that improves the adhesion to the substrate can be used.

Examples of compounds that improve film thickness uniformity and surface smoothness include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants. More specifically, for example, F-top EF301, EF303, EF352 (manufactured by Tochem Products), MegaFuck F171, F173, R-30 (manufactured by Dainippon Ink), Florard FC430, FC431 (manufactured by Sumitomo 3M) Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.). The use ratio of these surfactants is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass with respect to 100 parts by mass of the resin component contained in the liquid crystal aligning agent. .

Specific examples of the compound that improves the adhesion between the liquid crystal alignment film and the substrate include the following 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, N, N, N ′ , N′-tetraglycidyl-4, 4′-diaminodiphenylmethane and the like.

When a compound that improves the adhesion to the substrate is used, the addition amount thereof is 0.1 to 30 mass with respect to 100 mass parts of the resin component contained in the liquid crystal aligning agent, that is, the specific polymer. Parts, and more preferably 1 to 20 parts by mass. If the amount 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 orientation of the liquid crystal may deteriorate.

The liquid crystal aligning agent of the present invention comprises a crosslinkable compound having an epoxy group, an isocyanate group, an oxetane group or a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group, and a lower alkoxyalkyl group unless the effects of the present invention are impaired. A crosslinkable compound having at least one substituent selected from the group or a crosslinkable compound having a polymerizable unsaturated bond can be contained.

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, Liglycidyl-p-aminophenol, tetraglycidylmetaxylenediamine, 2- (4- (2,3-epoxypropoxy) phenyl) -2- (4- (1,1-bis (4- (2,3-epoxy) Propoxy) phenyl) ethyl) phenyl) propane, 1,3-bis (4- (1- (4- (2,3-epoxypropoxy) phenyl) -1- (4- (1- (4- (2,3 -Epoxypropoxyphenyl) -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 [8].

Specifically, it is a crosslinkable compound represented by the following formulas [8-1] to [8-11].

The crosslinkable compound having a cyclocarbonate group is a crosslinkable compound having at least two cyclocarbonate groups represented by the following formula [9].

Specifically, it is a crosslinkable compound represented by the following formulas [9-1] to [9-37].

(In the formula [9-24], n is an integer of 1 to 5, and in the formula [9-25], n is an integer of 1 to 5, and in the formula [9-36], n is 1 to 100. (In the formula [9-37], n is an integer of 1 to 10.)

Furthermore, polysiloxanes having at least one structure represented by the following formulas [9-38] to [9-40] can also be mentioned.

(In the formulas [9-38] to [9-40], R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each independently a structure represented by the formula [9], a hydrogen atom, a hydroxyl group, An alkyl group having 1 to 10 carbon atoms, an alkoxyl group, an aliphatic ring or an aromatic ring, at least one of which is a structure represented by the formula [9]).

More specifically, compounds of the following formulas [9-41] and [9-42] can be mentioned.

(In the formula [9-41], each R ₆ independently represents a structure represented by the formula [9], a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxyl group, an aliphatic ring or an aromatic group. A ring, at least one of which is a structure represented by the formula [9], wherein n is an integer of 1 to 10 in the formula [9-42].

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

Examples of such melamine derivatives or benzoguanamine derivatives include MX-750, which has an average of 3.7 substituted methoxymethyl groups per triazine ring, and an average of 5. methoxymethyl groups per triazine ring. Eight-substituted MW-30 (Sanwa Chemical Co., Ltd.) and Cymel 300, 301, 303, 350, 370, 771, 325, 327, 703, 712 and other methoxymethylated melamines, Cymel 235, 236 Methoxymethylated butoxymethylated melamine such as 238, 212, 253, 254, butoxymethylated melamine such as Cymel 506, 508, carboxyl group-containing methoxymethylated isobutoxymethylated melamine such as Cymel 1141, Cymel 1123 and the like Methoxymethylated ethoxy Methylated butoxymethylated benzoguanamine such as silylated 1112-10, butoxymethylated benzoguanamine such as Cymel 1128, carboxyl group-containing methoxymethylated ethoxymethylated benzoguanamine such as Cymel 1125-80 Cyanamide) and the like. Examples of glycoluril include butoxymethylated glycoluril such as Cymel 1170, methylolated glycoluril such as Cymel 1172, methoxymethylolated glycoluril such as Powderlink 1174, and the like.
Examples of the benzene or phenolic compound having a hydroxyl group or an alkoxyl group include 1,3,5-tris (methoxymethyl) benzene, 1,2,4-tris (isopropoxymethyl) benzene, 1,4-bis ( sec-butoxymethyl) benzene, 2,6-dihydroxymethyl-p-tert-butylphenol and the like.
Specifically, the crosslinkable compounds represented by the formulas [6-1] to [6-48], which are listed on pages 62 to 66 of International Publication No. WO2011 / 132751 (published 2011.10.27). It is done.

Examples of the crosslinkable compound having a polymerizable unsaturated bond include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, and tri (meth) acryloyloxyethoxytrimethylol. Crosslinkable compounds having three polymerizable unsaturated groups in the molecule such as propane or glycerin polyglycidyl ether poly (meth) acrylate; ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) ) Acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (me ) 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, diglycidyl ester phthalate di (meth) acrylate, neopentyl glycol dihydroxypivalate Crosslinkable compounds having two polymerizable unsaturated groups in the molecule such as (meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropylene (Meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 3-chloro-2-hydroxypropyl ( Crosslinkable compounds having one polymerizable unsaturated group in the molecule such as (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl phosphate ester, N-methylol (meth) acrylamide; Can be mentioned.
Furthermore, a compound represented by the following formula [11] can also be used.

In the formula [11], E ₁ is a group selected from the group consisting of a cyclohexane ring, a bicyclohexane ring, a benzene ring, a biphenyl ring, a terphenyl ring, a naphthalene ring, a fluorene ring, an anthracene ring and a phenanthrene ring, and E ₂ Is a group selected from the following formula [11a] and formula [11b], and n is an integer of 1 to 4.

The said compound is an example of a crosslinkable compound, It is not limited to these.
Moreover, the crosslinkable compound contained in the liquid crystal aligning agent of this invention may be one type, and may be combined two or more types.
The content of the crosslinkable compound in the liquid crystal aligning agent of the present invention is preferably 0.1 to 150 parts by mass with respect to 100 parts by mass of the polymer component. In order for the crosslinking reaction to proceed and to exhibit the desired effect and not to reduce the orientation of the liquid crystal, the amount is more preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the polymer component, and 1 to 50 parts by weight. Most preferred.

In addition to the above, the liquid crystal alignment treatment agent of the present invention is a dielectric or conductive material for the purpose of improving the electrical properties such as dielectric constant and conductivity of the liquid crystal alignment film as long as the effects of the present invention are not impaired. May be added.
As a compound that promotes charge transfer in a liquid crystal alignment film formed using a liquid crystal alignment treatment agent and promotes charge removal of a liquid crystal cell using the liquid crystal alignment film, International Publication No. WO2011-132751 (2011.10. 27), nitrogen-containing heterocyclic amine compounds represented by the formulas [M1] to [M156] described on pages 69 to 73 can also be added. These amine compounds may be added directly to the solution of the composition, but it is preferable to add them after making a solution with a concentration of 0.1 to 10% by mass, preferably 1 to 7% by mass with an appropriate solvent. . The solvent is not particularly limited as long as it is an organic solvent capable of dissolving polyamic acid and polyimide in addition to the compound of the above formula [1].

<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. Further, in the case of vertical alignment use, a liquid crystal alignment film can be formed without alignment treatment.
The substrate 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 simplification of the process, it is preferable to use a substrate on which an ITO 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 method for applying the liquid crystal aligning agent is not particularly limited, but industrially, methods such as screen printing, offset printing, flexographic printing, and ink jet methods are generally used. Other coating methods include a dipping method, a roll coater method, a slit coater method, a spinner method, and a spray method, and these may be used depending on the purpose. Even if the orientation processing agent of this invention is a case where the above application | coating method is used, applicability | paintability is favorable.

After the liquid crystal aligning agent is applied on the substrate, when polyimide is mainly contained as the specific polymer, it is preferably 50 to 300 ° C. by a heating means such as a hot plate, a thermal circulation oven, an IR (infrared) oven, etc. Can be formed into a coating film by evaporating the solvent at 80 to 250 ° C.

If the thickness of the coating 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. Therefore, it is preferably 5 to 300 nm, more preferably 10 to 100 nm. When the liquid crystal is horizontally or tilted, the baked coating 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 method described above, and then preparing a liquid crystal cell by a known method.

As a method for manufacturing a liquid crystal cell, prepare a pair of substrates on which a liquid crystal alignment film is formed, spray spacers on the liquid crystal alignment film of one substrate, and place the other side of the liquid crystal alignment film on the other side. And a method of sealing the substrate by injecting liquid crystal under reduced pressure, a method of bonding the substrate after dropping the liquid crystal on the surface of the liquid crystal alignment film on which the spacers are dispersed, and the like.
The liquid crystal alignment film of the present invention has a liquid crystal layer between a pair of substrates provided with electrodes, and includes a polymerizable compound that is polymerized by at least one of active energy rays and heat between the pair of substrates. It is also preferably used for a liquid crystal display device manufactured through a process of polymerizing a polymerizable compound by arranging at least one of active energy rays and heating while applying a voltage between electrodes. Here, ultraviolet rays are suitable as the active energy ray.

The above liquid crystal display element controls the pretilt of liquid crystal molecules by a PSA (Polymer Sustained Alignment) method. In the PSA method, a small amount of a photopolymerizable compound, for example, a photopolymerizable monomer is mixed in a liquid crystal material, and after assembling a liquid crystal cell, a predetermined voltage is applied to the liquid crystal layer and an ultraviolet ray is applied to the photopolymerizable compound. 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 method is suitable for forming a vertical alignment type liquid crystal layer that does not require a rubbing process and 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 a 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. By doing so, the orientation of the liquid crystal molecules can be controlled.
To give an example of manufacturing a PSA type liquid crystal cell, 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. Then, the other substrate is bonded, the liquid crystal is injected under reduced pressure and sealed, the liquid crystal is dropped on the liquid crystal alignment film surface on which the spacers are dispersed, and then the substrate is bonded and sealed. .

In the liquid crystal, 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 applying heat or ultraviolet light while applying an alternating current or direct current 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. The liquid crystal display element manufactured through the process of arrange | positioning the liquid crystal aligning film containing this, and applying a voltage between electrodes is used preferably. Here, ultraviolet rays are suitable as the active energy ray.

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 a liquid crystal aligning agent, a polymer containing a polymerizable group Examples include methods using components. Since the liquid crystal aligning agent of the present invention contains a specific compound having a double bond site that reacts by irradiation with heat or ultraviolet rays, the alignment of liquid crystal molecules can be controlled by at least one of ultraviolet irradiation and heating. it can.

If an example of liquid crystal cell production is given, prepare a pair of substrates on which a liquid crystal alignment film is formed, spread spacers on the liquid crystal alignment film of one substrate, and make the liquid crystal alignment film surface inside, Examples include a method in which the other substrate is bonded and liquid crystal is injected under reduced pressure to seal, and a method in which the liquid crystal is dropped on the liquid crystal alignment film surface on which spacers are dispersed and then the substrate is bonded and sealed.

The liquid crystal display element of the present invention is obtained through the above steps. Since these liquid crystal display elements have the liquid crystal alignment film of the present invention, the manufacturing process becomes lower temperature, excellent in reliability, and can be suitably used for large-screen high-definition liquid crystal televisions. It is.

The composition of the present invention can be used for forming a polyimide film in applications other than the liquid crystal alignment treatment agent used for forming the liquid crystal alignment film. For example, in other electronic devices, it can be used to form an interlayer insulating film and a protective film. In that case, various components can be added to the composition of the present invention depending on the application.

Examples are given below, but the present invention should not be construed as being limited thereto.
Abbreviations used in the examples and comparative examples are as follows.

<Diamine compound having a carboxyl group in the molecule>
D1: 3,5-diaminobenzoic acid D2: 1,4-diaminobenzoic acid

<Second diamine compound having a structure represented by the formula [5]>
D3: m-phenylenediamine D4: diamine 5: 1,3-diamino-4- (octadecyloxy) benzene D5: diamine 6: 1,3-diamino-4- [4- (trans-4-n-heptylcyclohexyl) ) Phenoxy] benzene D6: 1,3-diamino-4- {4- [trans-4- (trans-4-n-pentylcyclohexyl) cyclohexyl] phenoxy} benzene

<Other diamine compounds>
D7: p-phenylenediamine

<Tetracarboxylic dianhydride>
M1: 1,2,3,4-cyclobutanetetracarboxylic dianhydride M2: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride M3: 3,4-di Carboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride M4: 2,3,5-tricarboxycyclopentyl acetic acid dianhydride

<Compound with the structure represented by the formula [1] (organic solvent)>
DEME: Diethylene glycol monomethyl ether DEEE: Diethylene glycol monoethyl ether <other compound (solvent)>
NMP: N-methyl-2-pyrrolidone BCS: Ethylene glycol monobutyl ether

The physical properties such as molecular weight and imidization rate of polyamide acid and polyimide were evaluated as follows.

(Molecular weight measurement of polyamic acid and polyimide)
The molecular weights of the polyamic acid and the polyimide are as follows using a normal temperature gel permeation chromatography (GPC) apparatus (GPC-101) (manufactured by Showa Denko KK) and columns (KD-803, KD-805) (manufactured by Shodex). The measurement was performed as described above.
Column temperature: 50 ° C
Eluent: N, N′-dimethylformamide (as an additive, lithium bromide-hydrate (LiBr · H ₂ O) is 30 mmol / L (liter), phosphoric acid / anhydrous crystal (o-phosphoric acid) is 30 mmol / L, tetrahydrofuran (THF) 10ml / L)
Flow rate: 1.0 ml / min Standard sample for preparing 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)
The imidation ratio of polyimide in the synthesis example was measured as follows. Polyimide powder (20 mg) was put into an NMR sample tube (NMR sampling tube standard φ5 (manufactured by Kusano Kagaku)) and deuterated dimethyl sulfoxide (DMSO-d6, 0.05 mass% TMS (tetramethylsilane) mixture) ( 0.53 ml) was added and completely dissolved by applying ultrasonic waves. This solution was measured for proton NMR at 500 MHz with an NMR measuring instrument (JNW-ECA500) (manufactured by JEOL Datum). The imidation rate is determined based on protons derived from structures that do not change before and after imidation as reference protons, and the peak integrated value of these protons and proton peaks derived from NH groups of amic acid appearing in the vicinity of 9.5 to 10.0 ppm. It calculated | required by the following formula | equation using the integrated value.
Imidization rate (%) = (1−α · x / y) × 100
In the above formula, x is a proton peak integrated value derived from NH group of amic acid, y is a peak integrated value of reference proton, α is one NH group proton of amic acid in the case of polyamic acid (imidation rate is 0%) Is the number ratio of the reference proton to.

<Synthesis of polyimide>
<Synthesis Example 1>
M2 (3.94 g, 15.7 mmol), D1 (1.60 g, 10.5 mmol), and D6 (4.56 g, 10.5 mmol) were mixed in NMP (30.31 g) and at 80 ° C. for 5 hours. After the reaction, M1 (1.01 g, 5.2 mmol) and NMP (14.1 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (1.93 g) and pyridine (1.49 g) were added as an imidization catalyst and reacted at 80 ° C. for 3 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (A). The imidation ratio of this polyimide (A) was 55%, the number average molecular weight was 21,300, and the weight average molecular weight was 63,800.

<Synthesis Example 2>
M2 (4.32 g, 17.3 mmol), D1 (2.80 g, 18.4 mmol), and D6 (2.00 g, 4.6 mmol) were mixed in NMP (27.3 g) and at 80 ° C. for 5 hours. After the reaction, M1 (1.07 g, 5.5 mmol) and NMP (13.4 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.29 g) and pyridine (1.78 g) are added as an imidization catalyst and reacted at 80 ° C. for 3 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (B). The imidation ratio of this polyimide (B) was 51%, the number average molecular weight was 18,400, and the weight average molecular weight was 57,100.

<Synthesis Example 3>
M2 (9.01 g, 36.0 mmol), D1 (6.57 g, 43.2 mmol), and D6 (2.09 g, 4.8 mmol) were mixed in NMP (53.0 g) and at 80 ° C. for 5 hours. After the reaction, M1 (2.21 g, 11.3 mmol) and NMP (26.5 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.44 g) and pyridine (1.90 g) were added as an imidization catalyst, and the mixture was stirred at 90 ° C. for 2.5 hours. Reacted. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (C). The imidation ratio of this polyimide (C) was 52%, the number average molecular weight was 15,700, and the weight average molecular weight was 50,100.

<Synthesis Example 4>
M2 (5.07 g, 20.3 mmol) and D1 (4.11 g, 27.0 mmol) were mixed in NMP (27.5 g), reacted at 80 ° C. for 5 hours, and then M1 (1.22 g, 6.2 mmol) and NMP (14.1 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.63 g) and pyridine (2.04 g) were added as imidation catalysts, and the mixture was stirred at 90 ° C. for 2.5 hours. Reacted. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (D). The imidation ratio of this polyimide (D) was 49%, the number average molecular weight was 15,700, and the weight average molecular weight was 47,000.

<Synthesis Example 5>
M2 (6.13 g, 24.5 mmol) and D1 (3.80 g, 25.0 mmol) were mixed in NMP (39.7 g) and reacted at 80 ° C. for 16 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.54 g) and pyridine (1.97 g) were added as imidization catalysts, and 3.5 hours at 90 ° C. Reacted. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (E). The imidation ratio of this polyimide (E) was 49%, the number average molecular weight was 14,800, and the weight average molecular weight was 42,200.

<Synthesis Example 6>
M2 (17.7 g, 70.7 mmol), D1 (8.20 g, 53.9 mmol), and D6 (12.6 g, 29.0 mmol) were mixed in NMP (115.5 g) and at 80 ° C. for 5 hours. After the reaction, M1 (2.35 g, 12.0 mmol) and NMP (47.6 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.48 g) and pyridine (1.28 g) were added as an imidization catalyst and reacted at 90 ° C. for 2 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (F). The imidation ratio of this polyimide (F) was 53%, the number average molecular weight was 18,900, and the weight average molecular weight was 51,400.

<Synthesis Example 7>
M2 (5.25 g, 21.0 mmol), D1 (4.15 g, 27.3 mmol), and D6 (6.40 g, 14.7 mmol) were mixed in NMP (47.4 g) and at 80 ° C. for 5 hours. After the reaction, M1 (4.10 g, 20.9 mmol) and NMP (31.9 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.15 g) and pyridine (1.67 g) were added as imidization catalysts, and 3.5 hours at 80 ° C. Reacted. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (G). The imidation ratio of this polyimide (G) was 63%, the number average molecular weight was 19,400, and the weight average molecular weight was 60,400.

<Synthesis Example 8>
M2 (1.67 g, 6.7 mmol), D1 (2.14 g, 14.1 mmol), and D6 (3.35 g, 7.7 mmol) were mixed in NMP (21.5 g) and at 80 ° C. for 5 hours. After the reaction, M1 (2.93 g, 14.9 mmol) and NMP (18.9 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.20 g) and pyridine (1.71 g) were added as imidization catalysts, and 1.5 hours at 50 ° C. Reacted. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (H). The imidation ratio of this polyimide (H) was 55%, the number average molecular weight was 21,600, and the weight average molecular weight was 61,400.

<Synthesis Example 9>
M2 (4.13 g, 16.5 mmol), D1 (2.34 g, 15.4 mmol), and D4 (2.49 g, 6.6 mmol) were mixed in NMP (26.9 g) and at 80 ° C. for 5 hours. After the reaction, M1 (1.03 g, 5.3 mmol) and NMP (13.1 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.24 g) and pyridine (1.73 g) were added as an imidization catalyst and reacted at 80 ° C. for 3 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (I). The imidation ratio of this polyimide (I) was 55%, the number average molecular weight was 18,900, and the weight average molecular weight was 59,000.

<Synthesis Example 10>
M2 (4.13 g, 16.5 mmol), D1 (2.34 g, 15.4 mmol), and D5 (2.51 g, 6.6 mmol) were mixed in NMP (27.0 g) and at 80 ° C. for 5 hours. After the reaction, M1 (1.04 g, 5.3 mmol) and NMP (13.1 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.23 g) and pyridine (1.73 g) were added as an imidization catalyst and reacted at 80 ° C. for 3 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (J). The imidation ratio of this polyimide (J) was 50%, the number average molecular weight was 19,700, and the weight average molecular weight was 60,000.

<Synthesis Example 11>
M2 (4.13 g, 16.5 mmol), D2 (2.34 g, 15.4 mmol), and D5 (2.51 g, 6.6 mmol) were mixed in NMP (27.0 g) and at 80 ° C. for 5 hours. After the reaction, M1 (1.06 g, 5.4 mmol) and NMP (13.2 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.23 g) and pyridine (1.73 g) were added as an imidization catalyst, and the mixture was reacted at 80 ° C. for 3 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (K). The imidation ratio of this polyimide (K) was 52%, the number average molecular weight was 17,900, and the weight average molecular weight was 57,600.

<Synthesis Example 12>
M2 (8.07 g, 32.3 mmol), D1 (4.58 g, 30.1 mmol), and D6 (5.61 g, 12.9 mmol) were mixed in NMP (54.8 g) and at 80 ° C. for 5 hours. After the reaction, M1 (2.05 g, 10.5 mmol) and NMP (26.5 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (80.0 g) and diluting to 6% by mass, acetic anhydride (17.25 g) and pyridine (5.35 g) were added as an imidization catalyst and reacted at 100 ° C. for 3 hours. It was. This reaction solution was poured into methanol (1010 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 (L). The imidation ratio of this polyimide (L) was 80%, the number average molecular weight was 20,500, and the weight average molecular weight was 53,100.

<Synthesis Example 13>
M2 (17.7 g, 70.7 mmol), D1 (8.18 g, 53.8 mmol), and D6 (12.5 g, 28.8 mmol) were mixed in NMP (115.5 g) and at 80 ° C. for 5 hours. After the reaction, M1 (2.28 g, 11.7 mmol) and NMP (47.6 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.48 g) and pyridine (1.28 g) were added as an imidization catalyst, and the mixture was added at 100 ° C. for 2.5 hours. Reacted. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (M). The imidation ratio of this polyimide (M) was 70%, the number average molecular weight was 19,300, and the weight average molecular weight was 54,000.

<Synthesis Example 14>
M3 (6.91 g, 23.0 mmol), D1 (2.45 g, 16.1 mmol), and D5 (2.63 g, 6.9 mmol) were mixed in NMP (47.9 g) and 40 ° C. for 40 hours. Reaction was performed to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (3.92 g) and pyridine (3.04 g) were added as an imidization catalyst, and the mixture was heated at 40 ° C. for 1.5 hours. Reacted. This reaction solution was poured into methanol (260 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (N). The imidation ratio of this polyimide (N) was 69%, the number average molecular weight was 10,900, and the weight average molecular weight was 24,400.

<Synthesis Example 15>
M4 (5.13 g, 22.9 mmol), D1 (2.45 g, 16.1 mmol), and D5 (2.63 g, 6.9 mmol) were mixed in NMP (40.8 g) and at 60 ° C. for 24 hours. Reaction was performed to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (2.30 g) and pyridine (1.78 g) were added as an imidization catalyst and reacted at 90 ° C. for 2 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (O). The imidation ratio of this polyimide (O) was 49%, the number average molecular weight was 15,800, and the weight average molecular weight was 36,500.

<Synthesis Example 16>
M4 (5.13 g, 22.9 mmol), D1 (2.45 g, 16.1 mmol), and D5 (2.63 g, 6.9 mmol) were mixed in NMP (40.8 g) and at 60 ° C. for 24 hours. Reaction was performed to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (4.59 g) and pyridine (1.78 g) were added as an imidization catalyst and reacted at 100 ° C. for 3 hours. It was. This reaction solution was poured into methanol (260 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (P). The imidation ratio of this polyimide (P) was 77%, the number average molecular weight was 14,600, and the weight average molecular weight was 32,200.

<Synthesis Example 17>
M2 (5.07 g, 20.3 mmol) and D1 (4.11 g, 27.0 mmol) were mixed in NMP (27.5 g), reacted at 80 ° C. for 5 hours, and then M1 (1.22 g, 6.2 mmol) and NMP (14.1 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (5.26 g) and pyridine (2.04 g) were added as an imidization catalyst and reacted at 100 ° C. for 4 hours. It was. This reaction solution was poured into methanol (250 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (Q). The imidation ratio of this polyimide (Q) was 79%, the number average molecular weight was 15,000, and the weight average molecular weight was 45,700.

<Synthesis Example 18>
M2 (2.87 g, 11.5 mmol), D3 (1.24 g, 11.5 mmol), D1 (0.70 g, 4.6 mmol), and D6 (3.00 g, 6.9 mmol) were added to NMP (23.5 g). ) And reacted at 80 ° C. for 5 hours, M1 (2.21 g, 11.3 mmol) and NMP (16.7 g) were added, and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (4.66 g) and pyridine (1.81 g) were added as an imidization catalyst and reacted at 50 ° C. for 3 hours. It was. This reaction solution was poured into methanol (256 ml), and the resulting precipitate was filtered off. This precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain polyimide powder (R). The imidation ratio of this polyimide (R) was 49%, the number average molecular weight was 20,700, and the weight average molecular weight was 61,100.

<Synthesis Example 19>
M2 (2.87 g, 11.5 mmol), D7 (1.24 g, 11.5 mmol), D1 (0.70 g, 4.6 mmol), and D6 (3.00 g, 6.9 mmol) were added to NMP (23.5 g). ) And reacted at 80 ° C. for 5 hours, M1 (2.24 g, 11.4 mmol) and NMP (16.7 g) were added, and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 6% by mass, acetic anhydride (4.66 g) and pyridine (1.81 g) were added as an imidization catalyst and reacted at 50 ° C. for 3 hours. It was. This reaction solution was poured into methanol (256 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (S). The imidation ratio of this polyimide (S) was 51%, the number average molecular weight was 16,200, and the weight average molecular weight was 49,900.

<Synthesis Example 20>
M2 (5.63 g, 22.5 mmol) and D7 (3.24 g, 30.0 mmol) were mixed in NMP (26.6 g), reacted at 40 ° C. for 5 hours, and then M1 (1.24 g, 6.3 mmol) and NMP (13.8 g) were added and reacted at 25 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (20.0 g) and diluting to 5% by mass, acetic anhydride (2.96 g) and pyridine (2.29 g) were added as imidization catalysts, and the mixture was stirred at 90 ° C. for 2.5 hours. Reacted. This reaction solution was put into methanol (300 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 (T). The imidation ratio of this polyimide (T) was 51%, the number average molecular weight was 15,300, and the weight average molecular weight was 68,800. This polyimide does not use a diamine compound having a carboxyl group in the molecule as a diamine component.

<Synthesis Example 21>
M2 (11.2 g, 44.8 mmol) and D3 (6.49 g, 60.0 mmol) were mixed in NMP (53.2 g), reacted at 80 ° C. for 5 hours, and then M1 (2.73 g, 14.0 mmol) and NMP (28.7 g) were added and reacted at 40 ° C. for 6 hours to obtain a polyamic acid solution.
After adding NMP to this polyamic acid solution (30.0 g) and diluting to 6% by mass, acetic anhydride (4.44 g) and pyridine (3.44 g) were added as imidization catalysts, and the mixture was stirred at 90 ° C. for 2.5 hours. Reacted. This reaction solution was poured into methanol (380 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (U). The imidation ratio of this polyimide (U) was 50%, the number average molecular weight was 17,600, and the weight average molecular weight was 52,000. This polyimide does not use a diamine compound having a carboxyl group in the molecule as a diamine component.
Table 1 summarizes the compositions and imidization ratios of the polyimides obtained in Synthesis Examples 1 to 21.

<Polyimide solubility test>
<Examples 1 to 19, Comparative Example 1 and Comparative Example 2>
Comparison of the solubility of DEME (diethylene glycol monomethyl ether) and DEEE (diethylene glycol monoethyl ether) in each solvent using the polyimide powders (A) to (S) obtained in Synthesis Examples 1 to 19 as Examples 1 to 19 Went.
Similarly, as Comparative Examples 1 and 2, the solubility of DEME and DEEE in each solvent was compared using the polyimide powders (T) and (U) obtained in Synthesis Examples 20 and 21.

The test method is as follows. That is, DEME (15.7 g) was added to each of the polyimide powders (A) to (S) (1.0 g), stirred at 25 ° C. for 24 hours, and visually checked for the presence or absence of turbidity or precipitation. The sex was confirmed.
Furthermore, using DEEE, a test was performed in the same manner as described above, and the solubility was confirmed by visually confirming the presence or absence of turbidity or precipitation.
At that time, turbidity and precipitation did not occur, and a uniform solution was dissolved, and turbidity and precipitation were insoluble.
Table 2 summarizes the results of the solubility tests of Examples 1 to 19, Comparative Example 1 and Comparative Example 2.

From the results obtained in Examples 1 to 19, it was confirmed that the polyimide powders (A) to (S) of the examples were uniformly dissolved in DEME and DEEE. On the other hand, it was found that the polyimide powders (T) and (U) of the comparative examples were insoluble in these solvents.

<Preparation of a composition containing a polyimide and a solvent and a liquid crystal alignment treatment agent>
<Examples 20 to 27>
Synthesis Example 1, Synthesis Example 8, Synthesis Example 9, Synthesis Example 10, Synthesis Example 12, Synthesis Example 14, Synthesis Example 15 and Synthesis Example 15 Polyimide powders (A), (H), (I), ( JME, (L), (N), (O) and (P) (each 2.0 g) were added with DEME (28.0 g) and stirred at 50 ° C. for 24 hours to dissolve each polyimide. I let you. In any of the polyimide solutions, no abnormality such as turbidity or precipitation was observed, and it was confirmed that the solution was uniform.
Next, the obtained polyimide solutions were pressure filtered through a membrane filter having a pore diameter of 1 μm to obtain liquid crystal aligning agents (1) to (8) having a polyimide component content of 5 mass%.

<Examples 28 to 35>
Synthesis Example 1, Synthesis Example 8, Synthesis Example 9, Synthesis Example 10, Synthesis Example 12, Synthesis Example 14, Synthesis Example 15 and Synthesis Example 15 Polyimide powders (A), (H), (I), ( DE) (28.0 g) was added to each of J), (L), (N), (O) and (P) (each 2.0 g), and stirred at 50 ° C. for 24 hours to dissolve each polyimide. I let you. In any of the polyimide solutions, no abnormality such as turbidity or precipitation was observed, and it was confirmed that the solution was uniform.
Next, the obtained polyimide solutions were pressure filtered through a membrane filter having a pore diameter of 1 μm to obtain liquid crystal alignment agents (9) to (16) having a polyimide component content of 5 mass%.

<Examples 36 to 39>
In each of the polyimide powders (A), (J), (L) and (P) (2.0 g each) obtained in Synthesis Example 1, Synthesis Example 10, Synthesis Example 12 and Synthesis Example 16, DEME (26. 0 g) was added and stirred at 50 ° C. for 24 hours to dissolve each polyimide. Further, NMP (12.0 g) was added to each of the obtained solutions and stirred to obtain each polyimide solution. In any of the polyimide solutions, no abnormality such as turbidity or precipitation was observed, and it was confirmed that the solution was uniform.
Subsequently, the obtained polyimide solutions were pressure filtered through a membrane filter having a pore diameter of 1 μm to obtain liquid crystal alignment agents (17) to (20) having a polyimide component content of 5 mass%.

<Examples 40 to 43>
In each of the polyimide powders (A), (J), (L), and (P) (each 2.0 g) obtained in Synthesis Example 1, Synthesis Example 10, Synthesis Example 12, and Synthesis Example 16, DEME (18. 0 g) was added and stirred at 50 ° C. for 24 hours to dissolve each polyimide. Further, NMP (12.0 g) and BCS (8.0 g) were added to each of the obtained solutions and stirred to obtain each polyimide solution. In any of the polyimide solutions, no abnormality such as turbidity or precipitation was observed, and it was confirmed that the solution was uniform.
Next, each obtained polyimide solution was pressure filtered through a membrane filter having a pore diameter of 1 μm to obtain liquid crystal alignment agents (21) to (24) having a polyimide component content of 5 mass%.

<Examples 44 to 47>
In each of the polyimide powders (A), (J), (L) and (P) (each 2.0 g) obtained in Synthesis Example 1, Synthesis Example 10, Synthesis Example 12 and Synthesis Example 16, DEEE (18. 0 g) was added and stirred at 50 ° C. for 24 hours to dissolve each polyimide. Further, NMP (12.0 g) was added to each of the obtained solutions and stirred to obtain each polyimide solution. In any of the polyimide solutions, no abnormality such as turbidity or precipitation was observed, and it was confirmed that the solution was uniform.
Next, the obtained polyimide solutions were pressure filtered through a membrane filter having a pore diameter of 1 μm to obtain liquid crystal alignment agents (25) to (28) having a polyimide component content of 5 mass%.

<Comparative Example 3>
NMP (31.3 g) was added to the polyimide powder (A) (2.0 g) of Example 1 and stirred at 50 ° C. for 24 hours to dissolve the polyimide. No abnormality such as turbidity or precipitation was observed in this polyimide solution, and it was confirmed that the polyimide solution was a uniform solution.
Subsequently, each polyimide solution obtained was pressure filtered through a membrane filter having a pore diameter of 1 μm to obtain a liquid crystal alignment agent (29) having a polyimide component content of 6 mass%.
Tables 3 and 4 show the solvents and solubility in the liquid crystal aligning agents obtained in Examples 20 to 47 and Comparative Example 3.

<Production of liquid crystal alignment film and production of liquid crystal display element>
A liquid crystal alignment film was prepared using the liquid crystal aligning agents (1) to (28) obtained in Examples 20 to 47, and a liquid crystal surface element having the liquid crystal alignment film was manufactured. As the liquid crystal display element, a vertically aligned liquid crystal cell was manufactured in accordance with the characteristics of the liquid crystal alignment film.

As a method for producing a liquid crystal cell, the liquid crystal alignment treatment agents (1) to (28) are spin-coated on a glass substrate with an ITO electrode (thickness 0.7 mm, width 30 mm, length 40 mm) on a hot plate at 80 ° C. After drying for 5 minutes, it baked at 220 degreeC, the liquid crystal aligning film was formed as a coating film with a film thickness of 100 nm, and the board | substrate with a liquid crystal aligning film was obtained. It was found that all of the liquid crystal alignment films formed on the substrate were excellent in film thickness uniformity, and the liquid crystal alignment treatment agents (1) to (28) exhibited excellent coating properties.

Two substrates with this liquid crystal alignment film were prepared, 6 μm spacers were sprayed on one liquid crystal alignment film surface, and then a sealant (XN-1500T, manufactured by Mitsui Chemicals) was printed thereon. Next, after bonding the other substrate and the liquid crystal alignment film face each other, the sealing agent was cured by heat treatment at 150 ° C. for 90 minutes in a heat-circulating clean oven to produce an empty cell. . Nematic liquid crystal (MLC-6608, manufactured by Merck & Co., Inc.) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain a vertically aligned liquid crystal cell.

For the obtained liquid crystal cell, the alignment state of the liquid crystal was observed with a polarizing microscope, and it was confirmed that uniform vertical alignment of the liquid crystal without defects was formed.

Table 5 summarizes the results of the alignment state of the liquid crystal of the liquid crystal display element.

<Printability test>
Printing was performed using the liquid crystal alignment treatment agents obtained in Example 20, Example 28, Example 36, Example 40, Example 44, and Comparative Example 3. Printing is performed using a simple printing machine (S15 type, manufactured by Nissha Printing Co., Ltd.) as a printing machine, on a cleaned chromium vapor deposition substrate, with a printing area of 8 cm × 8 cm, a printing pressure of 0.2 mm, five discarded substrates, and temporary printing. The drying time was 90 seconds, the temporary drying temperature was 70 ° C., and the temporary drying time was 5 minutes.

The pinhole was confirmed by visual observation under a sodium lamp. Specifically, the entire coating film was visually observed under a sodium lamp, and the number of pinholes existing on the coating film surface was counted.
Confirmation of film thickness unevenness was performed using an optical microscope. Specifically, the coating film surface is observed with an optical microscope, the coating film surface has no film thickness unevenness A, the coating film surface has a partially uneven film thickness B, the entire coating film surface In the case where the film thickness unevenness was observed, C was determined.

The results are summarized in Table 6.

From the above results, the present invention is made from a composition containing a polyimide precursor obtained by using a diamine component containing a diamine compound having a specific structure having a carboxyl group and / or a polyimide obtained by imidizing a polyimide precursor and a compound (solvent). It was found that the liquid crystal aligning agent can be obtained, and the liquid crystal aligning agent is excellent in coatability. Furthermore, it was found that the liquid crystal alignment film that can be obtained using the liquid crystal alignment treatment agent of the present invention can provide a highly reliable liquid crystal display element with few defects.

The composition of the present invention can be widely used for the formation of films such as interlayer insulation films and protective films in electronic devices, etc. Especially as a liquid crystal alignment treatment agent, it has excellent coating properties and suppresses defects such as repellency and pinholes. Used for forming a highly reliable liquid crystal alignment film.

The entire contents of the description, claims and abstract of Japanese Patent Application No. 2011-153523 filed on July 12, 2011 are incorporated herein as the disclosure of the specification of the present invention. It is.

Claims (14)

1. A polyimide precursor obtained by reacting a diamine component containing a diamine compound having a carboxyl group and a tetracarboxylic acid component and / or a polyimide obtained by imidizing the polyimide precursor, a compound represented by the following formula [1], The composition characterized by containing.
   

   

   (In the formula [1], R ₁ is an alkyl group having 1 to 4 carbon atoms.)
2. The composition according to claim 1, wherein the compound represented by the formula [1] is a compound represented by the following formula [2] or the following formula [3].
   

   

   
3. 3. The composition according to claim 1, wherein the diamine compound having a carboxyl group has a — (CH ₂ ) _a —COOH group (a is an integer of 0 to 4).
4. The composition according to any one of claims 1 to 3, wherein the diamine compound having a carboxyl group is a diamine compound having a structure represented by the following formula [4].
   

   

   (In the formula [4], a represents an integer of 0 to 4, and n represents an integer of 1 to 4.)
5. The composition according to any one of claims 1 to 4, wherein the content of the diamine compound is 20 to 100 mol% in the diamine component.
6. The composition according to any one of claims 1 to 5, wherein the diamine component includes a second diamine compound having a structure represented by the following formula [5].
   

   

   (In the formula [5], X represents a — (CH ₂ ) _b —OH group (b is an integer of 0 to 4), a hydrocarbon group having 1 to 22 carbon atoms, and a hydrocarbon group having 1 to 6 carbon atoms. And a di-substituted amino group substituted by or a group represented by the following formula [6], and n represents an integer of 1 to 4.)
   

   

   (In formula [6], Y ¹ is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. Y ² is a single bond or (CH ₂ ) _b — (b is an integer of 1 to 15) Y ³ is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15) ), —O—, —CH ₂ O—, —COO— or OCO— Y ⁴ is a divalent cyclic group selected from a benzene ring, a cyclohexyl ring and a heterocyclic ring (on these cyclic groups) The optional hydrogen atom is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. it may be substituted), or a divalent organic group having a carbon number of 12 to 25 having a steroid skeleton .Y ⁵ A divalent cyclic group selected from a benzene ring, a cyclohexyl ring and a heterocyclic ring (an arbitrary hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, carbon Y ⁶ is a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, a carbon atom, which may be substituted with a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. A fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorine-containing alkoxyl group having 1 to 18 carbon atoms, n represents an integer of 0 to 4.)
7. The composition according to any one of claims 1 to 6, wherein the tetracarboxylic dianhydride is a compound represented by the following formula [7].
   

   

   (In Formula [7], Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms and contains a non-aromatic cyclic hydrocarbon group having 4 to 10 carbon atoms.)
8. The composition according to claim 7, wherein Z ₁ has a structure represented by the following formulas [7a] to [7j].
   

   

   (In the formula [7a], Z ₂ to Z ₅ are a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, which may be the same or different. In the formula [7g], Z ₆ and Z ₇ Are hydrogen atoms or methyl groups, which may be the same or different.
9. A liquid crystal aligning agent comprising the composition according to any one of claims 1 to 8.
10. A liquid crystal alignment film obtained from the liquid crystal aligning agent according to claim 9.
11. The liquid crystal aligning film obtained by the inkjet method using the liquid-crystal aligning agent of Claim 9.
12. 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 12. The liquid crystal alignment film according to claim 10, wherein the liquid crystal alignment film is used for a liquid crystal display device manufactured through a step of polymerizing the polymerizable compound while applying a voltage therebetween.
13. A liquid crystal display element having the liquid crystal alignment film according to claim 10.
14. A liquid crystal composition comprising a polymerizable compound having a liquid crystal layer between a pair of substrates provided with an electrode and the liquid crystal alignment film and polymerized between at least one of active energy rays and heat between the pair of substrates. The liquid crystal display element according to claim 13, wherein the liquid crystal display element is manufactured through a step of polymerizing the polymerizable compound while applying a voltage between the electrodes.