WO2011155576A1

WO2011155576A1 - Liquid crystal alignment treatment agent, liquid crystal alignment film, and liquid crystal display element

Info

Publication number: WO2011155576A1
Application number: PCT/JP2011/063288
Authority: WO
Inventors: 幸司園山; 悟志南; 徳俊三木; 雅章片山
Original assignee: 日産化学工業株式会社
Priority date: 2010-06-10
Filing date: 2011-06-09
Publication date: 2011-12-15
Also published as: CN103038704A; CN103038704B; KR20130109095A; JP2016026162A; KR101823714B1; TWI504637B; JPWO2011155576A1; JP5998930B2; TW201221552A; JP6065074B2

Abstract

Disclosed is a liquid crystal alignment film which has a satisfactory level of solvent resistance and in which the reduction in a voltage holding ratio can be prevented even when exposed to irradiation with light. The liquid crystal alignment film is produced using a diamine compound represented by formula [2]. In the formula, X₁ represents -O-, -NH-, -N(CH₃)-, -CONH-, -NHCO-, -CH₂O-, -COO-, -OCO-, -CON(CH₃)- or N(CH₃)CO-; X₂ represents an alkylene group having 1 to 5 carbon atoms; X₃ represents a structure represented by formula [1a]; and n represents an integer of 1 to 4.

Description

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

The present invention relates to a diamine compound, a polymer such as a polyimide precursor or polyimide obtained using the diamine compound, a liquid crystal alignment treatment agent containing the polymer, a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent, and the liquid crystal alignment The present invention relates to a liquid crystal display element using a film.

The liquid crystal alignment film is a constituent member of a liquid crystal display element widely used as a display device, and plays a role of aligning liquid crystals in a certain direction. Currently, the main liquid crystal alignment film used industrially is formed from a liquid crystal alignment treatment agent comprising a polyamic acid (also referred to as polyamic acid) which is a polyimide precursor or a polyimide solution. Specifically, after a liquid crystal alignment treatment agent is applied to the substrate and heated, an alignment treatment for aligning the liquid crystal in parallel or with respect to the substrate surface is performed. Examples of the alignment treatment include surface stretching treatment by rubbing, but in addition to this, alignment treatment using an anisotropic optical reaction such as irradiation with polarized ultraviolet rays has been proposed.

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 a certain direction. Furthermore, in recent years, liquid crystal display elements have become highly functional, and the range of use has been expanded, and the liquid crystal alignment film has performance and reliability for realizing high display quality by suppressing display defects of the liquid crystal display elements. Is required.

For example, the rubbing process described above is performed by rubbing the surface of the liquid crystal alignment film with a cloth. From the standpoint of measures against foreign matters, the liquid crystal alignment film has a slight degree of scraping due to the rubbing process. There is a demand for high rubbing resistance (high mechanical strength). Patent Document 1 describes that a polyimide-based liquid crystal aligning agent contains a compound having two or more epoxy groups in a molecule for the purpose of improving rubbing resistance.

Japanese Unexamined Patent Publication No. 9-146100

In the manufacturing process of the liquid crystal panel constituting the liquid crystal display element, the liquid crystal alignment film is washed with water or an organic solvent in order to remove a small amount of scraps generated during the rubbing process and impurities attached to the liquid crystal alignment film during baking. There is a process. In this case, it is necessary that the liquid crystal alignment film does not dissolve in these cleaning liquids, particularly organic solvents, that is, the solvent resistance is high. When the liquid crystal alignment film is dissolved in the cleaning liquid, a liquid crystal alignment film having a predetermined film thickness cannot be obtained, and it is difficult to achieve high display quality in the liquid crystal display element.

Also, along with the recent improvement in performance of liquid crystal display elements, liquid crystal display elements are used for large-screen, high-definition liquid crystal televisions and in-vehicle applications such as car navigation systems and meter panels. In such applications, in order to obtain high luminance, a backlight with a large calorific value may be used. In this case, high stability with respect to light from the backlight is required. In particular, if the voltage holding ratio, which is one of the electrical characteristics, decreases due to light irradiation from the backlight, a seizure defect (linear seizure) that is one of the display defects of the liquid crystal display element is likely to occur. As a result, a highly reliable liquid crystal display element cannot be obtained. Therefore, in the liquid crystal alignment film, in addition to good initial characteristics, there is a demand for characteristics in which, for example, the voltage holding ratio is not easily lowered even after being exposed to light irradiation for a long time.

An object of the present invention is to provide a liquid crystal alignment film having the above characteristics. That is, an object of the present invention is to provide a liquid crystal alignment film that has sufficient solvent resistance in a cleaning step during the manufacturing process of a liquid crystal panel and that suppresses a decrease in voltage holding ratio even when exposed to light irradiation, and the liquid crystal alignment Another object is to provide a liquid crystal aligning agent capable of obtaining a film, and a liquid crystal display element having excellent display quality using the liquid crystal aligning agent.

Also, an object of the present invention is to provide a polyimide precursor, a polyimide, and a diamine compound for obtaining the polyimide precursor and the polyimide constituting the liquid crystal aligning agent.

As a result of intensive studies, the inventor has obtained the following knowledge and completed the present invention. That is, by using a diamine compound having a specific structure, a polyimide precursor having a characteristic structure is obtained, and it is found that a polyimide having a characteristic structure can be obtained by imidizing this polyimide precursor. It was.
And the liquid crystal aligning agent comprised including at least one of these polyimide precursors and polyimide is suitable for forming a liquid crystal aligning film, and the obtained liquid crystal aligning film is the above-mentioned present invention. It was found to be extremely effective in achieving the purpose. The diamine compound having the specific structure described above includes a novel compound that has not been published in the literature.

The present invention has the following gist.
1. A liquid crystal aligning agent comprising a polyimide precursor having a cyclocarbonate group and at least one polymer selected from the group consisting of polyimides obtained by imidizing the polyimide precursor.
2. 2. The liquid crystal aligning agent according to 1 above, wherein the cyclocarbonate group is present at an end of a side chain of the polyimide precursor and the polyimide.
3. The liquid-crystal aligning agent of said 1 or 2 with which the side chain which has the said cyclocarbonate group is represented by following formula [1].

(X ₁ is —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —COO—, —OCO—, —CON (CH ₃ ) — Or N (CH ₃ ) CO—, X ₂ is an alkylene group having 1 to 5 carbon atoms, and X ₃ has a structure represented by the following formula [1a].)

4). 4. The liquid crystal aligning agent according to any one of 1 to 3 above, wherein the polyimide precursor and the polyimide are polymers made from a diamine compound represented by the following formula [2].

(X ₁ is —O—, —NH—, —N (CH ₃ ) —, —CONH—, —NHCO—, —CH ₂ O—, —COO—, —OCO—, —CON (CH ₃ ) — Or N (CH ₃ ) CO—, X ₂ is an alkylene group having 1 to 5 carbon atoms, X ₃ is a structure represented by the following formula [1a], and n is an integer of 1 to 4 is there.)

5. 5. The liquid crystal aligning agent according to any one of the above 1 to 4, further comprising a base having a primary amino group and a nitrogen-containing heterocyclic ring in the molecular structure.
6). 6. The liquid crystal aligning agent according to 5 above, wherein the base is at least one compound selected from the group consisting of 3-aminopropylimidazole and 3-picolylamine.
7). 7. The liquid crystal alignment treatment agent according to any one of the above 1 to 6, comprising an organic solvent that dissolves the polyimide precursor and the polyimide, and the organic solvent contains 5 to 80% by mass of a poor solvent in the liquid crystal alignment treatment agent. .
8). 8. A liquid crystal alignment film obtained from the liquid crystal alignment treatment agent according to any one of 1 to 7 above.
9. 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 9. The liquid crystal alignment film as described in 8 above, which is used in a liquid crystal display device produced through a step of polymerizing the polymerizable compound while applying a voltage therebetween.
10. 10. A liquid crystal display device having the liquid crystal alignment film as described in 9 above.
11. 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 polymerizing at least one of active energy rays and heat between the pair of substrates. 11. The liquid crystal display device as described in 10 above, which is produced through a step of polymerizing the polymerizable compound while applying a voltage between the electrodes.
12 A diamine compound represented by the following formula [2].

13. A polyimide precursor obtained by reacting a diamine component containing the diamine compound described in 12 above and an acid dianhydride component.
14 The polyimide precursor according to 13 above, wherein the diamine component further contains a diamine compound represented by the following formula [3].

(Y ₁ is a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 10), —O—, —CH ₂ O—, —COO—, and —OCO—. Y ₂ is a divalent organic group, Y ₂ is a single bond or a divalent organic group selected from (CH ₂ ) _b — (b is an integer of 1 to 10), Y ₃ is a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 10), a divalent organic group selected from the group consisting of —O—, —CH ₂ O—, —COO—, and —OCO—. Y ₄ is a cyclic group selected from the group consisting of a benzene ring, a cyclohexyl ring and a heterocyclic ring, and an arbitrary hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, a carbon number 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 fluorine Is a divalent organic group selected from an organic group having a carbon number of 12-25 with substituted by 2 may be a monovalent organic group, or steroid skeleton atom .Y ₅ is cyclohexyl ring a benzene ring, cyclohexane And a cyclic group selected from the group consisting of heterocyclic rings, wherein any hydrogen atom on the cyclic group is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, or 1 to 3 carbon atoms. A fluorine-containing alkyl group, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a divalent organic group which may be substituted with a fluorine atom, n is an integer of 0 to 4. Y ₆ is a carbon number 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, and m is an integer of 1 to 4. .)
15. The polyimide precursor according to the above 13 or 14, wherein the acid dianhydride component is a tetracarboxylic dianhydride represented by the following formula [4].

(Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms and has a non-aromatic cyclic hydrocarbon group having 4 to 10 carbon atoms.)
16. 16. The liquid crystal aligning agent according to 15, wherein Z ₁ in the tetracarboxylic dianhydride is an organic group having a structure of any one of the following formulas [4a] to [4j].

(In Formula [4a], Z ₂ to Z ₅ are each independently a group selected from a hydrogen atom, a methyl group, a chlorine atom, or a benzene ring. In Formula [4g], Z ₆ and Z ₇ are And each independently represents a hydrogen atom or a methyl group.)
17. A polyimide obtained by dehydrating and ring-closing the polyimide precursor according to any one of the above 13 to 15.

The liquid crystal alignment film obtained by using the liquid crystal alignment treatment agent of the present invention has sufficient solvent resistance in the washing step during the liquid crystal panel manufacturing process, and the voltage holding ratio is reduced even when exposed to light irradiation. It is suppressed. Furthermore, the liquid crystal display element having this liquid crystal alignment film has excellent display quality.
Moreover, according to this invention, the novel diamine compound which is a raw material of the said liquid-crystal aligning agent is provided, and the polyimide precursor and polyimide which are manufactured from a diamine compound are also provided.

The liquid crystal aligning agent of the present invention contains at least one of a polyimide precursor having a cyclocarbonate group and a polyimide obtained by dehydrating and ring-closing this polyimide precursor. Here, the cyclocarbonate group is preferably located at each side chain end of the polyimide precursor and the polyimide.

Specifically, the liquid crystal aligning agent of the present invention contains at least one of a polyimide precursor having a side chain of the following formula [1] and a polyimide obtained by dehydrating and ring-closing this polyimide precursor. is there.

In the formula [1], X ₁ represents —O— (ether bond), —NH— (amino bond), —N (CH ₃ ) — (methylated amino bond), —CONH— (amide bond), —NHCO. -(Reverse amide bond), -CH ₂ O- (methylene ether bond), -COO- (ester bond), -OCO- (reverse ester bond), -CON (CH ₃ )-(N-methylated amide bond) And a linking group selected from the group consisting of N (CH ₃ ) CO— (N-methylated reverse amide bond). X ₁ is —O—, —NH—, —CONH—, —NHCO—, —CON (CH ₃ ) —, —CH ₂ O—, — since the synthesis of the raw materials is easy and relatively easy to obtain. COO- or OCO- is preferred. More preferred is —O—, —CONH—, —CON (CH ₃ ) —, —CH ₂ O— or COO—.

In the formula [1], X ₂ is an alkylene group having 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms.

In the formula [1], X ₃ represents a cyclocarbonate group. Specifically, X ₃ is preferably a structure represented by the following formula [1a].

The cyclocarbonate group present at the end of the side chain in the formula [1] reacts with at least one of a carboxyl group and a hydroxyl group under heating to form a crosslinked structure of the polymer. Thereby, it can be set as the liquid crystal aligning film excellent in solvent tolerance, and also excellent in stability with respect to light irradiation, such as a backlight.

Also, when the cyclocarbonate group is located at the end of the side chain of the formula [1], a liquid crystal alignment film having a high crosslink density and high elongation and toughness can be obtained. Thereby, since the stretchability of the polymer is hardly inhibited during rubbing, high rubbing resistance can be realized. Furthermore, since the cyclocarbonate group at the end of the side chain can efficiently promote the crosslinking reaction, even when a crosslinkable compound is added, unreacted liquid crystal display device characteristics are deteriorated. Residual crosslinkable compounds can also be reduced.

Thus, the liquid crystal alignment film obtained from the liquid crystal alignment treatment agent is excellent in solvent resistance in the manufacturing process of the liquid crystal panel, and the voltage holding ratio is not greatly reduced due to the influence of light irradiation by the backlight. Furthermore, since the rubbing resistance is also excellent, a liquid crystal display element having excellent display quality can be obtained by applying this liquid crystal alignment film.

Hereinafter, the diamine compound having a specific structure used in the liquid crystal aligning agent of the present invention will be described in detail. The liquid crystal alignment treatment agent of the present invention can contain other components in addition to the polyimide precursor and polyimide, and preferably includes a basic compound as a base, other diamine compounds, and the like. The

<Specific diamine compound>
The liquid-crystal aligning agent of this invention is a polyimide precursor obtained by reaction of a diamine component and tetracarboxylic dianhydride, and a polyimide obtained by dehydrating and ring-closing this polyimide precursor (in the present specification, these are generically referred to). May be referred to as a specific polymer). The diamine component preferably contains a diamine compound represented by the following formula [2] (also referred to herein as a specific diamine compound).

In the formula [2], X ₁ , X ₂ , and X ₃ have the same definition as in the above formula [1]. In the formula [2], n is an integer of 1 to 4, preferably n is an integer of 1 to 2, and more preferably n is 1.

The bonding position of the _two amino groups (—NH ₂ ) in the formula [2] is not limited. Specifically, with respect to the linking group (X ₁ ) of the side chain, 2, 3 position, 2, 4 position, 2, 5 position, 2, 6 position, 3, 4 position on the benzene ring Position, 3, 5 positions. Among these, from the viewpoint of reactivity at the time of synthesizing the polyamic acid, the 2,4 position, the 2,5 position, and the 3,5 position are preferable.

Preferred combinations of X ₁ , X ₂ , X ₃ and n in the formula [2] are as shown in combination numbers (2-1) to (2-15) shown in Table 1.

<Method for synthesizing specific diamine compound>
Although the method to manufacture the specific diamine compound shown by Formula [2] is not specifically limited, What is shown below is mentioned as a preferable method.

As an example, the specific diamine compound of the present invention can be obtained by synthesizing a dinitro compound represented by the following formula [2A], 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 or platinum sulfide carbon is used as a catalyst, and ethyl acetate, toluene, tetrahydrofuran, dioxane or There is a method in which hydrogen gas, hydrazine, hydrogen chloride, or the like is used in a solvent such as an alcohol solvent. X ₁ , X ₂ , X ₃ and n in the formula [2A] are the same as defined in the formula [2] in the specific diamine compound described above.

In the dinitro compound of the formula [2A], X ₁ and X ₃ are bonded via X ₂ and then bonded to the dinitro moiety via X ₁ , as well as the dinitro moiety and X via the linking moiety X _1. by binding and _2, then, it can be obtained by a method of bonding with X _3.

These linking groups can be formed by appropriately selecting and using known methods in organic synthesis. For example, when X ₁ is an ether or methylene ether bond, as a method for forming it, there is a method in which a corresponding dinitro group-containing halogen derivative and a hydroxyl group derivative containing X ₂ and X ₃ are reacted in the presence of an alkali. And a method of reacting a dinitro group-containing hydroxyl group derivative with a halogen-substituted derivative containing X ₂ and X ₃ in the presence of an alkali.

In addition, when X ₁ is an amino bond, a method of reacting a corresponding dinitro group-containing halogen derivative with an amino group-substituted derivative containing X ₂ and X ₃ in the presence of an alkali can be mentioned.

In addition, when X ₁ is an amide bond, a method of reacting a corresponding dinitro group-containing acid chloride and an amino group-substituted product containing X ₂ and X ₃ in the presence of an alkali can be mentioned.

Moreover, X ₁ is the opposite case an amide bond, and the corresponding dinitro group-containing amino group substituents, a method of reacting an acid chloride containing the X ₂ and X ₃ in the presence of alkalis.

In addition, when X ₁ is an ester bond, a method in which a corresponding dinitro group-containing acid chloride is reacted with a hydroxyl group-substituted derivative containing X ₂ and X ₃ in the presence of an alkali can be mentioned.

Moreover, X ₁ is the case of reverse ester bond, and the corresponding dinitro group-containing hydroxyl derivative, a method of reacting an acid chloride containing the X ₂ and X ₃ in the presence of alkalis.

Specific examples of dinitro group-containing halogen derivatives and dinitro group-containing derivatives include 3,5-dinitrochlorobenzene, 2,4-dinitrochlorobenzene, 2,4-dinitrofluorobenzene, 3,5-dinitrobenzoic acid chloride, 3,5 -Dinitrobenzoic acid, 2,4-dinitrobenzoic acid chloride, 2,4-dinitrobenzoic acid, 3,5-dinitrobenzyl chloride, 2,4-dinitrobenzyl chloride, 3,5-dinitrobenzyl alcohol, 2,4- Dinitrobenzyl alcohol, 2,4-dinitroaniline, 3,5-dinitroaniline, 2,6-dinitroaniline, 2,4-dinitrophenol, 2,5-dinitrophenol, 2,6-dinitrophenol or 2,4- And dinitrophenylacetic acid. In consideration of the method of obtaining the raw materials, easiness and reactivity, one or more of them can be selected and used.

<Basic compound>
The liquid crystal aligning agent of the present invention preferably contains a basic compound as a base for the purpose of advancing the crosslinking reaction of the cyclocarbonate group of the polyimide precursor or polyimide. The type of the basic compound is not particularly limited as long as it has sufficient basicity to advance the crosslinking reaction of the cyclocarbonate group.

Specific examples include alkali metal or alkaline earth metal hydroxides such as sodium hydroxide and potassium hydroxide, inorganic amine compounds such as ammonia, and organic amine compounds such as pyridine and triethylamine. Of these, organic amine compounds are preferred from the viewpoint of the electrical characteristics of the liquid crystal alignment film.

More specifically, examples of the organic amine compound include nitrogen-containing heterocyclic amine compounds represented by the following formulas [M1] to [M156].
These amine compounds may be added directly to the solution of the specific polymer, but may be added after a solution having a concentration of 0.1 to 10% by mass, preferably 1 to 7% by mass with an appropriate solvent. preferable. The solvent is not particularly limited as long as it is an organic solvent that dissolves the specific polymer of the present invention.

More preferable organic amine compounds include M6, M7, M16, M17, M20, M35, M36, M40, M49, M50, M60 to M62, M69, M70, M76, M118 to M121, M135, or M140. Further preferred are M6, M16, M17, M35, M36, M40, M49, M50, M60, M61, M118, M120, M121, or M140. Most preferred is M6, M17, M35, M40, M61 or M118.

The basic compound contained in the liquid-crystal aligning agent of this invention may be one type, and may combine two or more types.
In the liquid crystal aligning agent of the present invention, the content of the basic compound is preferably 0.1 to 100 parts by mass with respect to 100 parts by mass of the specific polymer, and the carboxylic acid contained in the polyamic acid or polyimide In order to promote the reaction with the group or the hydroxyl group and not to deteriorate the orientation of the liquid crystal, the amount is more preferably 0.1 to 50 parts by mass, particularly 1 to 30 parts by mass.

<Polyimide precursor and polyimide>
In the present invention, the specific polymer is at least one polymer selected from the group consisting of a polyimide precursor and polyimide.
The specific polymer is relatively easily obtained by polycondensing a diamine component represented by the following formula [A] and a tetracarboxylic dianhydride component represented by the following formula [B]. A polyamic acid having a repeating unit represented by the formula [C], and a polyimide obtained by imidizing this polyamic acid are preferred.

In the formula [B], R ₁ represents a divalent organic group, and R ₂ represents a tetravalent organic group.

In the formula [C], R ₁ and R ₂ have the same meanings as defined in the formula [A] and the formula [B], and R ₁ and R ₂ are different even if each is one kind. A combination of a plurality of species may be used, and n represents a positive integer.
The polyimide precursor and polyimide of this invention are obtained using the diamine component and acid dianhydride component containing the said specific diamine compound. Such a diamine component can contain a diamine compound represented by the following formula [3] (also referred to as a specific side chain diamine compound in the present specification).

In the formula [3], Y ₁ is selected from a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. It is a divalent organic group. Among these, a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 15), —O—, —CH ₂ O—, or COO— is preferable because a side chain structure can be easily synthesized. More preferably, they are a single bond, — (CH ₂ ) _a — (a is an integer of 1 to 10), —O—, —CH ₂ O— or COO—.

In the formula [3], Y ₂ is a single bond or a divalent organic group selected from (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 [3], Y ₃ is selected from a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO—. It is a divalent organic group. Among these, a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 15), —O—, —CH ₂ O—, —COO— or OCO— is preferable because they are easily synthesized. More preferably, they are a single bond, — (CH ₂ ) _c — (c is an integer of 1 to 10), —O—, —CH ₂ O—, —COO— or OCO—.

In the formula [3], Y ₄ is a cyclic group selected from the group consisting of a benzene ring, a cyclohexyl ring, and a heterocyclic ring, and any hydrogen atom on these cyclic groups has 1 to 3 carbon atoms. It may be substituted with a group selected from the group consisting of an 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, and a fluorine atom. It is a divalent organic group or a divalent organic group selected from a C 12-25 organic group having a steroid skeleton. Among these, an organic group having 12 to 25 carbon atoms having a benzene ring, a cyclohexyl ring or a steroid skeleton is preferable.

In the formula [3], Y ₅ is a cyclic group selected from the group consisting of a benzene ring, a cyclohexyl ring, and a heterocyclic ring, and any hydrogen atom on these cyclic groups has 1 to 3 carbon atoms. It may be substituted with an 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. It is a divalent organic group. Among these, a benzene ring or a cyclohexyl ring is preferable.

In the formula [3], Y ₆ represents an alkyl group having 1 to 18, preferably 1 to 12, more preferably 1 to 9 carbon atoms, 1 to 18 carbon atoms, preferably 1 to 12, more preferably 1 to 9 carbon atoms. A fluorine-containing alkyl group, an alkoxyl group having 1 to 18, preferably 1 to 12, more preferably 1 to 9 carbon atoms, or a fluorine containing group having 1 to 18, preferably 1 to 12, more preferably 1 to 9 carbon atoms An alkoxyl group;

In the formula [3], n is an integer of 0 to 4. Preferably, it is an integer of 0-2. M is an integer of 1 to 4. Preferably, it is an integer of 1 to 2.

Preferred combinations of Y ₁ , Y ₂ , Y ₃ , Y ₄ , Y ₅ , Y ₆ and n in the formula [3] are as shown in Tables 2 to 43.

More specifically, the specific side chain diamine compound represented by the formula [3] has a structure represented by the following formulas [3-1] to [3-31].

In the formulas [3-1] to [3-3], R ₁ represents —O—, —OCH ₂ —, —CH ₂ O—, —COOCH ₂ —, or —CH ₂ OCO—, and R ₂ 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 the formulas [3-4] to [3-6], R ₃ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ — or CH _2- , and 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 the formulas [3-7] and [3-8], R ₅ represents —COO—, —OCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH ₂ O—, —OCH ₂ —, — Represents CH ₂ — or O—, and R ₆ represents a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, an acetyl group, an acetoxy group or a hydroxyl group.

In the formulas [3-9] and [3-10], 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 the formulas [3-11] and [3-12], 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 [3-13], A ₄ represents an alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, and A ₃ represents a 1,4-cyclohexylene group or 1,4-phenylene. A ₂ is an oxygen atom or COO- * (where a bond marked with “*” is bonded to A ₃ ), and A ₁ is an oxygen atom or COO— * (where “ Bonds marked with “*” bind 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.

<Other diamine compounds>
Although the polyimide precursor of this invention can be obtained using the specific diamine compound represented by Formula [2], unless the effect of this invention is impaired, the specific side chain represented by the said Formula [3] Other diamine compounds can be used in combination with the type diamine compound. Specific examples of such other diamine compounds are listed below.

For example, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m-phenylenediamine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol 4,6-diaminoresorcinol, 4,4′-diaminobiphenyl, 3,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, 3,3 ′ -Dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diaminobi Enyl, 3,3′-difluoro-4,4′-biphenyl, 3,3′-trifluoromethyl-4,4′-diaminobiphenyl, 3,4′-diaminobiphenyl, 3,3′-diaminobiphenyl, 2, , 2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3 '-Diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'- Sulfonyl dianiline, 3,3'-sulfonyl dianiline 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′-diaminodiphenyl) amine, N-methyl (3,3′-diaminodiphenyl) amine, N-methyl (3,4′-diaminodiphenyl) amine, N-methyl (2,2′-diaminodiphenyl) amine, N-methyl (2,3′-diaminodiphenyl) amine, 4,4′-diaminobenzofe Non, 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-phenylenebis (methylene)] dianiline, 3,4 ′-[1,3- Phenylenebis (methylene)] dianiline, 3,3 ′-[1,4-phenylenebis (methylene)] dianiline, 3,3 ′-[1,3-phenylenebis (methylene)] dianiline, 1,4-phen Renbis [(4-aminophenyl) methanone], 1,4-phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [ (3-aminophenyl) methanone], 1,4-phenylenebis (4-aminobenzoate), 1,4-phenylenebis (3-aminobenzoate), 1,3-phenylenebis (4-aminobenzoate), 1, 3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N , N ′-(1,4-phenylene) bis (4-aminobenzamide), N, N ′-(1, 3-phenylene) bis (4-aminobenzamide), N, N ′-(1,4-phenylene) bis (3-aminobenzamide), N, N ′-(1,3-phenylene) bis (3-aminobenzamide) ), N, N′-bis (4-aminophenyl) terephthalamide, N, N′-bis (3-aminophenyl) terephthalamide, N, N′-bis (4-aminophenyl) isophthalamide, N, N '-Bis (3-aminophenyl) isophthalamide, 9,10-bis (4-aminophenyl) anthracene, 4,4'-bis (4-aminophenoxy) diphenylsulfone, 2,2'-bis [4- ( 4-aminophenoxy) phenyl] propane, 2,2′-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2′-bis (4-amino) Phenyl) hexafluoropropane, 2,2′-bis (3-aminophenyl) hexafluoropropane, 2,2′-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2′-bis (4 -Aminophenyl) propane, 2,2'-bis (3-aminophenyl) propane, 2,2'-bis (3-amino-4-methylphenyl) propane, 3,5-diaminobenzoic acid, 2,5- Diaminobenzoic acid, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3 -Aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bis (4-amino) Enoxy) 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, 1,12- (4 Aromatic diamines such as -aminophenoxy) dodecane and 1,12- (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) methane and bis (4-Amino-3-methylcyclohexyl) alicyclic diamine such as methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7 And aliphatic diamines such as -diaminoheptane, 1,8-diaminooctane, 1,9-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, or those having a macrocyclic substituent composed of these. it can. Specifically, diamines represented by the following formulas [DA1] to [DA12] can be exemplified.

In the formulas [DA1] to [DA5], A ₁ is an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group.

In the formulas [DA6] to [DA11], A ₂ represents —COO—, —OCO—, —CONH—, —NHCO—, —CH ₂ —, —O—, —CO— or NH—. ₃ represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group.

In the formula [DA12], p is an integer of 1 to 10. In addition, diamine compounds represented by the following formulas [DA13] to [DA20] can also be used as long as the effects of the present invention are not impaired.

In the formula [DA17], m is an integer of 0 to 3, and in the formula [DA20], n is an integer of 1 to 5.

Furthermore, as long as the effects of the present invention are not impaired, a diamine compound having a carboxyl group in the molecule represented by the following formulas [DA21] to [DA24] can also be used.

In the formula [DA21], m ₁ is an integer of 1 to 4. In the formula [DA22], A ₄ is 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 each represent an integer of 0 to 4, and m ₂ + m ₃ represents an integer of 1 to 4. In the formula [DA23], m ₄ and m ₅ are each an integer of 1 to 5. In the formula [DA24], A ₅ is a linear or branched alkyl group having 1 to 5 carbon atoms, and m ₆ is 1. An integer of ~ 5. In the formula [DA25], 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 above-mentioned specific side chain type diamine compound and other diamine compounds are used alone or in combination of two or more depending on the properties such as liquid crystal orientation, voltage holding ratio, accumulated charge, etc. You can also

<Tetracarboxylic dianhydride>
The polyimide precursor in this invention is obtained by reaction of a diamine component and a tetracarboxylic acid component. Below, the specific example of a tetracarboxylic-acid component is given.

In order to obtain the specific polymer of the present invention, a tetracarboxylic dianhydride represented by the following formula [4] (also referred to as a specific tetracarboxylic dianhydride in this specification) is used as a part of the raw material. It is preferable to use it.

In the formula [4], Z ₁ is a tetravalent organic group having 4 to 13 carbon atoms, and has a non-aromatic cyclic hydrocarbon group having 4 to 10 carbon atoms, preferably 4 to 6 carbon atoms.

Preferred specific examples of Z ₁ are shown by the following formulas [4a] to [4j].

In the formula [4a], Z ₂ to Z ₅ are groups selected from a hydrogen atom, a methyl group, a chlorine atom and a benzene ring, and may be the same or different.

In the formula [4g], Z ₆ and Z ₇ are a hydrogen atom or a methyl group, and may be the same or different.

In the formula [4], particularly preferred structure of Z ₁ is the formula [4a], the formula [4c], the formula [4d], the formula [4e], the formula [4f] or the formula because of the polymerization reactivity and the ease of synthesis. [4 g].

In the present invention, other tetracarboxylic dianhydrides other than the specific tetracarboxylic dianhydride can be used as long as the effects of the present invention are not impaired. Other tetracarboxylic dianhydrides include tetracarboxylic dianhydrides of the following tetracarboxylic acids. 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) Carboxyphenyl) 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 , 4-cyclobutanetetracarboxylic acid, oxydiphthaltetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5- Cyclohexanetetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl 1,2,3,4-cyclobutanetetracarboxylic acid, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cycloheptanetetracarboxylic acid, 2,3, 4,5-tetrahydrofurantetracarboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro -1-naphthalene succinic acid, bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid, bicyclo [4,3,0] nonane-2,4,7,9-tetracarboxylic acid Bicyclo [4,4,0] decane-2,4,7,9-tetracarboxylic acid, bicyclo [4,4,0] decane-2,4,8,10-tetracarboxylic acid, tricyclo [6.3 0.0. 0 <2,6>] undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4- (2,5-dioxotetrahydrofuran-3-yl)- 1,2,3,4-tetrahydraphthalene-1,2-dicarboxylic acid, bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic acid, 5- (2, 5-Dioxotetrahydrofuryl) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid, tetracyclo [6,2,1,1,0,2,7] dodeca-4,5,9,10 -Tetracarboxylic acid, 3,5,6-tricarboxynorbornane-2: 3,5: 6 dicarboxylic acid or 1,2,4,5-cyclohexanetetracarboxylic acid.

In the present invention, one or more kinds of tetracarboxylic dianhydrides can be selected and used from the above-mentioned tetracarboxylic dianhydrides in consideration of characteristics such as liquid crystal orientation, voltage holding characteristics, and accumulated charges.

<Specific polymer>
The liquid crystal aligning agent of this invention contains at least one of the polyimide precursor which has a cyclocarbonate group, and the polyimide which imidated this polyimide precursor. In the present invention, the polyimide precursor and the polyimide may be collectively referred to as a specific polymer.
The polyimide precursor 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 polyamic acid having a structural formula of a repeating unit represented by the following formula [D] or a polyimide obtained by imidizing the polyamic acid is preferable.

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

In the present invention, the method for synthesizing the specific polymer is not particularly limited. Usually, it is obtained by reacting a diamine component and a tetracarboxylic acid component. 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 for obtaining polyamic acid by polycondensation of tetracarboxylic dianhydride and a diamine component, a method for 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.
To obtain the polyamic acid alkyl ester, a method of polycondensing a tetracarboxylic acid obtained by dialkyl esterifying a carboxylic acid group and a diamine component, a polycondensation of a tetracarboxylic acid dihalide obtained by dialkyl esterifying a carboxylic acid group and a 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.

As the ratio of the cyclocarbonate group in the specific polymer increases, the properties of the liquid crystal alignment film obtained by using the liquid crystal aligning agent containing the specific polymer become better. Specifically, the solvent resistance in the liquid crystal panel manufacturing process is excellent, and the rubbing resistance is also good. Furthermore, a decrease in voltage holding ratio is suppressed even when light is emitted from the backlight.

When a cyclocarbonate group is introduced into a specific polymer using a specific diamine compound, the specific diamine compound is 1 mol% or more of the diamine component, and more % Or more, more preferably 10 mol% or more. Moreover, 100 mol% of a diamine component can also be a specific diamine compound. However, the amount of the specific diamine compound used is preferably 80 mol% or less of the diamine component, more preferably 40 mol% or less, from the viewpoint of maintaining uniform coating properties when applying the liquid crystal aligning agent.

In obtaining the polyimide precursor of the present invention by the reaction of the diamine component and the tetracarboxylic acid component, a known synthesis method can be used. For example, it is possible to use a method in which a diamine component and a tetracarboxylic acid component are reacted in an organic solvent. This method is preferable in that the reaction proceeds relatively efficiently in an organic solvent and generation of by-products is small.

The organic solvent used for the reaction between the diamine component and the tetracarboxylic acid component is not particularly limited as long as the produced polyamic acid is soluble. Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ -Butyrolactone, isopropyl alcohol, methoxymethylpentanol, dipentene, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol , Ethyl carbitol, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol Monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl Ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol Methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n- Hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethylene carbonate, propylene carbonate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, Ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3- Tokishipuropion acid, 3-methoxy propionic acid propyl, 3-methoxy propionic acid butyl, and the like diglyme or 4-hydroxy-4-methyl-2-pentanone. These may be used alone or in combination. Moreover, even if it is a solvent which does not melt | dissolve a polyimide precursor, if it is the range which the produced | generated polyamic acid does not precipitate, it can also be mixed and used for the said 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. It is also possible to carry out the reaction at a high concentration at the beginning of the reaction and then add an organic solvent.

In the polymerization reaction of 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.

The polyimide of the present invention is obtained by dehydrating and ring-closing the above 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 can be adjusted within a range of 45 to 85%, for example, depending on the application and purpose. .

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

The temperature when the polyimide precursor is thermally imidized in a solution is 100 to 400 ° C., preferably 120 to 250 ° C., and it is preferable to carry out while removing water generated by the imidation 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, and trioctylamine. Among them, 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. Among them, acetic anhydride is preferable because purification after completion of the reaction is easy. The imidization rate by catalytic imidation can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

When recovering the produced polyimide precursor or polyimide from the polyimide precursor or polyimide reaction solution, the reaction solution may be poured into a poor solvent and precipitated. Examples of the poor solvent used for precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. The polymer deposited in a poor solvent and precipitated can be recovered by filtration and then dried at normal temperature or under reduced pressure at room temperature or by heating. In addition, when the polymer collected by precipitation is redissolved in an organic solvent and reprecipitation and collection is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of the poor solvent at this time include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more kinds of poor solvents selected from these because purification efficiency is further improved.

The molecular weight of the polymer contained in the liquid crystal aligning agent of the present invention is determined by considering the strength of the coating film obtained by using this, the workability during coating film formation, and the uniformity of the coating film, GPC (Gel Permeation Chromatography). The weight average molecular weight measured by the above method is preferably 5,000 to 1,000,000, and more preferably 10,000 to 150,000.

<Liquid crystal aligning agent>
The liquid crystal aligning agent of this invention is a coating liquid for forming a liquid crystal aligning film, and is a solution obtained by dissolving the resin component for forming the resin film which is a liquid crystal aligning film in an organic solvent. This resin component contains at least one polymer selected from the specific polymers described above. The content of the resin component in the liquid crystal aligning agent is preferably 1 to 20% by mass, more preferably 3 to 15% by mass, and particularly preferably 3 to 10% by mass.

In the present invention, all of the resin components contained in the liquid crystal aligning agent may be a specific polymer. Moreover, in addition to a specific polymer, you may use the other polyimide precursor or polyimide which does not have a cyclocarbonate group. Furthermore, a polymer other than a polyimide precursor and polyimide, specifically, an acrylic polymer, a methacrylic polymer, polystyrene, polyamide, or the like can be given. The content of the other specific polymer can be 0.5 to 15% by mass, and preferably 1 to 10% by mass.

When the liquid crystal aligning agent of the present invention contains an organic solvent, the content of the organic solvent is preferably 70 to 99% by mass, more preferably 80 to 99% by mass from the viewpoint of forming a uniform thin film by coating. . This content can be appropriately changed depending on the film thickness of the liquid crystal alignment film. The organic solvent in that case will not be specifically limited if it is an organic solvent in which the specific polymer mentioned above is dissolved. More specifically, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethyl-2-pyrrolidone, N-vinylpyrrolidone, Dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, Examples thereof include ethylene carbonate, propylene carbonate, diglyme and 4-hydroxy-4-methyl-2-pentanone. These may be used alone or in combination.

The liquid crystal aligning agent of the present invention has at least one selected from the group consisting of a crosslinkable compound having an epoxy group, an isocyanate group or an oxetane group, and a hydroxyl group and an alkoxyl group, as long as the effects of the present invention are not impaired. It is also possible to introduce a crosslinkable compound having a kind of substituent, in addition to a crosslinkable compound having a polymerizable unsaturated bond.

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

Examples of the crosslinkable compound having an oxetane group include a crosslinkable compound having at least two oxetane groups represented by the following formula [5].

Specifically, it is a crosslinkable compound represented by the following formulas [5-1] to [5-11].

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

As this crosslinkable compound, for example, a melamine derivative in which a hydrogen atom of an amino group is substituted with a methylol group or an alkoxymethyl group or both, a benzoguanamine derivative or glycoluril can be used. At this time, the melamine derivative and the benzoguanamine derivative can exist as a dimer or a trimer. These preferably have an average of 3 to 6 methylol groups or alkoxymethyl groups per triazine ring.

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

Examples of benzene having a hydroxyl group or an alkoxyl group, or phenolic compounds include 1,3,5-tris (methoxymethyl) benzene, 1,2,4-tris (isopropoxymethyl) benzene, and 1,4-bis. (Sec-butoxymethyl) benzene, 2,6-dihydroxymethyl-p-tert-butylphenol and the like.
More specifically, it is a crosslinkable compound represented by the following formulas [6-1] to [6-48].

Examples of the crosslinkable compound having a polymerizable unsaturated bond include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, tri (meth) acryloyloxyethoxytrimethylolpropane, Crosslinkable compounds having three polymerizable unsaturated groups in the molecule such as glycerin polyglycidyl ether poly (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meta ) Acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol di (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, in addition to 2-hydroxyethyl (meth) acrylate, 2-hydro Cypropyl (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, etc. Can be mentioned.

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

In the formula [7], A ₁ is a group selected from a cyclohexyl ring, a bicyclohexyl ring, a benzene ring, a biphenyl ring, a terphenyl ring, a naphthalene ring, a fluorene ring, an anthracene ring or a phenanthrene ring, and A ₂ is the following: A group selected from the formula [7a] or the formula [7b], and n is an integer of 1 to 4.

The above compound is an example of a crosslinkable compound and is not limited thereto. Moreover, the crosslinkable compound contained in the liquid crystal aligning agent of this invention may be one type, and may combine two or more types.

The content of the crosslinkable compound is preferably 0.1 to 150 parts by mass with respect to 100 parts by mass of the resin component in the liquid crystal aligning agent, the crosslinking reaction proceeds, and the desired effect is exhibited. In order not to lower the orientation of the liquid crystal, the amount is more preferably 0.1 to 100 parts by mass, particularly 1 to 50 parts by mass.

A nitrogen-containing heterocyclic amine compound represented by the following formulas [M1] to [M156] is added as a compound that promotes charge transfer in the liquid crystal alignment film and promotes charge release of the liquid crystal cell using the liquid crystal alignment film. You can also The amine compound may be added directly to the polymer solution, but it is preferably added after a solution having 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 that dissolves the above-described polymer.

Furthermore, the liquid crystal aligning agent of the present invention is also referred to as an organic solvent (poor solvent) that improves 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, a compound that improves the adhesion between the liquid crystal alignment film and the substrate, and the like can be used.

Specific examples of poor solvents that improve film thickness uniformity and surface smoothness include the following. For example, isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethyl carbitol acetate, ethylene glycol, ethylene glycol monoacetate, ethylene glycol monoacetate Isopropyl ether, ethylene glycol monobutyl ether, propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, dipro Lenglycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3 -Methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl Ether, n-hexane, n-pentane, n-octane, diethyl ether Methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, 3-methoxy Ethyl propionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 1-butoxy- 2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether Low surface tension such as ter-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol, lactate methyl ester, lactate ethyl ester, lactate n-propyl ester, lactate n-butyl ester or lactate isoamyl ester Such as a solvent. These poor solvents may be used alone or in combination. When the above poor solvent is used, the amount added is preferably 5 to 80% by mass, more preferably 20 to 60% by mass, based on the total amount of the solvent contained in the liquid crystal aligning agent.

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 or N, N, N ′ , N ′,-tetraglycidyl-4,4′-diaminodiphenylmethane and the like.

When a compound that improves the adhesion to the substrate is used, the amount of the compound added is preferably 0.1 to 30 parts by mass with respect to 100 parts by mass of the resin component contained in the liquid crystal aligning agent. More preferably, it is 1 to 20 parts by mass. If it is less than 0.1 part by mass, the effect of improving the adhesion cannot be expected, and if it exceeds 30 parts by mass, the orientation of the liquid crystal may deteriorate.

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 changing the electrical properties such as the dielectric constant and conductivity of the liquid crystal alignment film as long as the effects of the present invention are not impaired. May be added.

<Liquid crystal alignment film and liquid crystal display element>
The liquid crystal alignment treatment agent of the present invention can be used as a liquid crystal alignment film after being applied and baked on a substrate and then subjected to alignment treatment by rubbing treatment or light irradiation. In the case of vertical alignment, etc., it can be used as a liquid crystal alignment film without alignment treatment. The substrate used at this time is not particularly limited as long as it is a highly transparent substrate. In addition to a glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate can also be used. From the viewpoint of 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 are generally used. Other coating methods include dip, roll coater, slit coater, spinner and the like, and these may be used depending on the purpose.

After applying the liquid crystal aligning agent on the substrate, the solvent can be evaporated at 50 to 300 ° C., preferably 80 to 250 ° C. by a heating means such as a hot plate to form a coating film. 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 fired 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 above-described method 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, or a method of sealing the substrate by bonding the liquid crystal after dropping the liquid crystal on the liquid crystal alignment film surface on which the spacers are dispersed.

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-mentioned liquid crystal display element controls the pretilt angle 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 angle 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 angle of the liquid crystal molecules can be adjusted by controlling the electric field formed in the liquid crystal layer. . The PSA method does not require a rubbing process and is suitable for forming a vertical alignment type liquid crystal layer in which it is difficult to control the pretilt angle by the rubbing process.

That is, in the liquid crystal display element of the present invention, a liquid crystal cell is prepared after obtaining a substrate with a liquid crystal alignment film from the liquid crystal alignment treatment agent of the present invention by the above-described method, and a polymerizable compound is obtained by at least one of ultraviolet irradiation and heating. The orientation of the liquid crystal molecules can be controlled by polymerizing.

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 attached and liquid crystal is injected under reduced pressure, or a method in which liquid crystal is dropped on the surface of the liquid crystal alignment film on which spacers are dispersed and then the substrate is attached 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 producing the liquid crystal cell, the polymerizable compound is polymerized by irradiating with heat or ultraviolet rays while applying an AC or DC voltage to the liquid crystal cell. Thereby, the alignment of the liquid crystal molecules can be controlled.

The liquid crystal display element of the present invention can be obtained through the steps exemplified above. Since these liquid crystal display elements use the alignment film of the present invention as the liquid crystal alignment film, they have excellent reliability and can be suitably used for large-screen and high-definition liquid crystal televisions.

Hereinafter, an example will be given and described. The present invention is not construed as being limited to these.

The abbreviations used in Examples and Comparative Examples are as follows.

<Tetracarboxylic dianhydride>
A-1: 1,2,3,4-cyclobutanetetracarboxylic dianhydride A-2: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride

<Specific diamine compound>
B-1: Diamine compound synthesized in Example 1

<Other diamine compounds>
B-2: 3,5-diaminobenzoic acid B-3: 1,3-diamino-4- {4- [trans-4- (trans-4-n-pentylcyclohexyl) cyclohexyl] phenoxy} benzene

<Base>
C-1: 3 aminopropylimidazole C-2: 3 aminopyridine <organic solvent>
NMP: N-methyl-2-pyrrolidone BCS: Butyl cellosolve PGMEA: Propylene glycol monomethyl ether acetate PGME: Propylene glycol monomethyl ether IPA: Isopropyl alcohol DMSO: Dimethyl sulfoxide

In the examples, physical properties such as molecular weight and imidization rate regarding polyamic acid and polyimide were evaluated as follows.

<Molecular weight measurement of polyamic acid and polyimide>
As the molecular weight of the polyamic acid and polyimide, a normal temperature gel permeation chromatography (GPC) apparatus (GPC-101) manufactured by Showa Denko KK and a column (KD-803, KD-805) manufactured by Shodex were used. The measurement conditions are as follows.

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

<Measurement of imidization ratio>
Add 20 mg of polyimide powder to an NMR sample tube (Kusano Kagaku, NMR sampling tube standard φ5), and add 0.53 ml of deuterated dimethyl sulfoxide (DMSO-d6, 0.05% TMS (tetramethylsilane) mixture) Then, it was completely dissolved by applying ultrasonic waves. With respect to this solution, proton NMR at 500 MHz was measured using an NMR measuring instrument (JNW-ECA500) manufactured by JEOL Datum. The imidation rate is determined by determining a proton derived from a structure that does not change before and after imidation as a reference proton, and the peak integrated value of this proton and the proton peak derived from the NH group of amic acid that appears near 9.5 to 10.0 ppm. It calculated | required by the following Numerical formula (1) using the integrated value.

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

In the above formula (1), x is the proton peak integrated value derived from the NH group of the amic acid, y is the peak integrated value of the reference proton, and α is the NH group of the amic acid in the case of polyamic acid (imidation rate is 0%). It is the number ratio of the reference proton to one proton.

Next, a synthesis example of the specific diamine compound of the present invention is shown. In the synthesis examples, ¹ H-NMR means a nuclear magnetic resonance spectrum of an intramolecular hydrogen atom, and shows spectrum data of the obtained compound.

Example 1.
(Synthesis of diamine compounds)

The diamine compound (B-1) was synthesized according to the above synthesis scheme. Specifically, a solution of compound (302) (21.51 g, 182.2 mmol) and triethylamine (18.44 g, 182.2 mmol) in tetrahydrofuran (400 g) was cooled to 10 ° C. or lower, and the compound ( 301) (40.00 g, 173.5 mmol) in tetrahydrofuran (200 g) was added dropwise while paying attention to heat generation. After completion of the dropwise addition, the reaction temperature was raised to 23 ° C. and further reaction was performed. After confirming the completion of the reaction by HPLC (high performance liquid chromatograph), the reaction solution was poured into distilled water (4.8 L), the precipitated solid was filtered and washed with water, and then dispersed and washed with methanol (324 g). Compound (303) was obtained (amount obtained: 48.65 g, yield: 90%).
¹ H-NMR (400 MHz, DMSO-d6, δ ppm): 9.03 (1H, t), 8.87 (2H, d), 5.24-5.19 (1H, m), 4.67-4.57 (3H, m), 4.47 (1H, dd).

A mixture of compound (303) (40.00 g, 128.1 mmol), 5% palladium carbon (hydrous type, 4.0 g, 10 wt%), and 1,4-dioxane (600 g) was added in the presence of hydrogen in the presence of 23 Stir at ° C. After completion of the reaction, the catalyst was filtered through celite, and then the solvent was distilled off with an evaporator to obtain an oily crude product. Ethyl acetate (200 g) was added to the resulting crude product, and the mixture was crystallized while stirring with heating, followed by filtration and drying to obtain the diamine compound (B-1) as a white solid (yield: 17). .45 g, yield: 54%).
¹ H-NMR (400 MHz, DMSO-d6, δ ppm): 6.42 (2H, d), 6.04 (1H, t), 5.14-5.09 (1H, m), 5.03 (4H, br s), 4.62 (1H, t ), 4.50 (1H, dd), 4.39-4.32 (2H, m).

Example 2
<Synthesis 1 of polyamic acid>
A-2 (7.86 g, 31.4 mmol), B-3 (5.62 g, 12.9 mmol), B-2 (1.96 g, 12.9 mmol), and B-1 (2.79 g, 11. 0 mmol) was mixed in NMP (57.1 g) and reacted at 80 ° C. for 5 hours, and then A-1 (1.05 g, 5.51 mmol) and NMP (20.1 g) were added. It was made to react for a time and the solution (concentration 20.0 mass%) of the polyamic acid (A) was obtained. The number average molecular weight of this polyamic acid (A) was 25,528, and the weight average molecular weight was 97,025.

Example 3
<Synthesis of polyimide 1>
After adding NMP to the polyamic acid (A) solution (25.0 g) obtained in Example 2 and diluting to 6% by mass, acetic anhydride (4.88 g) and pyridine (1.51 g) were used as imidization catalysts. ) Was added and reacted at 100 ° C. for 2 hours. The reaction solution was poured into methanol (314 g), and the produced precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain a polyimide (B) powder. The imidation ratio of this polyimide (B) was 77%, the number average molecular weight was 18,898 and the weight average molecular weight was 102,005.

18.8 g of NMP was added to 3.85 g of polyimide (B) powder and dissolved by stirring at 70 ° C. for 30 hours to obtain a polyimide (B) solution.

Example 4
<Preparation 1 of liquid crystal aligning agent>
To the polyimide (B) solution obtained in Example 3, NMP, an NMP solution of C-1 and BCS were added and stirred at 50 ° C. for 20 hours. The polyimide was 6% by mass and C-1 was 0.3% by mass. %, NMP was 48.7% by mass, and BCS was 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Embodiment 5 FIG.
<Synthesis 2 of polyamic acid>
A-2 (8.29 g, 33.0 mmol), B-3 (5.93 g, 13.6 mmol), B-2 (2.96 g, 19.4 mmol), and B-1 (1.47 g, 5.3 mmol). 84 mmol) was mixed in NMP (58.8 g) and reacted at 80 ° C. for 5 hours, and then A-1 (1.14 g, 5.81 mmol) and NMP (20.3 g) were added. It was made to react for a time and the solution (concentration 20.0 mass%) of the polyamic acid (C) was obtained. The number average molecular weight of this polyamic acid (C) was 24,325, and the weight average molecular weight was 82,359.

Example 6
<Polyimide synthesis 2>
In the same manner as in Example 3, NMP was added to the polyamic acid (C) solution (25.0 g) obtained in Example 5 to dilute to a concentration of 6% by mass, and then acetic anhydride (5 0.02 g) and pyridine (1.55 g) were added and reacted at 100 ° C. for 2 hours. The reaction solution was poured into methanol (314 g), and the produced precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain a polyimide (D) powder. The imidation ratio of this polyimide (D) was 77%, the number average molecular weight was 20,405 and the weight average molecular weight was 82,988.

18.6 g of NMP was added to 3.82 g of polyimide (D) powder and dissolved by stirring at 70 ° C. for 30 hours to obtain a polyimide (D) solution.

Example 7
<Preparation 2 of liquid crystal aligning agent>
In the same manner as in Example 4, NMP, an NMP solution of C-1 and BCS were added to the polyimide (D) solution obtained in Example 6, and the mixture was stirred at 50 ° C. for 20 hours. -1 was 0.3% by mass, NMP was 48.7% by mass, and BCS was 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Example 8 FIG.
<Preparation 3 of liquid crystal aligning agent>
To the polyimide (B) solution obtained in Example 3, NMP, an NMP solution of C-2 and BCS were added and stirred at 50 ° C. for 15 hours. The polyimide was 6% by mass, and C-1 was 0.3% by mass. %, NMP was 48.7% by mass, and BCS was 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Example 9
<Preparation 4 of liquid crystal aligning agent>
To the polyimide (D) solution obtained in Example 6, NMP, an NMP solution of C-2 and BCS were added and stirred at 50 ° C. for 20 hours. The polyimide was 6% by mass, and C-1 was 0.3% by mass. %, NMP was 48.7% by mass, and BCS was 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Example 10
<Preparation 5 of liquid crystal aligning agent>
NMP and BCS were added to the polyimide solution (B) solution obtained in Example 3 and stirred to prepare 6% by mass of polyimide, 48.7% by mass of NMP, and 45% by mass of BCS. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Example 11
<Preparation 6 of liquid crystal aligning agent>
To the polyamic acid (A) solution obtained in Example 2, NMP, an NMP solution of C-2 and BCS were added and stirred, and 6% by mass of polyimide, 0.3% by mass of C-2, and NMP were added. It was prepared so that 48.7 mass% and BCS might be 45 mass%. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Example 12
<Preparation 7 of liquid crystal aligning agent>
To the polyamic acid (C) solution obtained in Example 5, NMP, an NMP solution of C-2 and BCS were added and stirred, and the polyamic acid (C) was 6% by mass and C-2 was 0.3% by mass. , NMP was 48.7% by mass and BCS was 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Example 13
<Preparation 8 of liquid crystal aligning agent>
NMP and BCS were added to the polyamic acid (A) solution obtained in Example 2 and stirred to prepare a polyimide content of 6 mass%, an NMP content of 48.7 mass%, and a BCS content of 45 mass%. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Below, the polyamic acid, polyimide, and liquid-crystal aligning agent as a comparative example are shown.
Comparative Example 1
A-2 (41.7 g, 166 mmol), B-3 (29.7 g, 68.3 mmol) and B-2 (19.4 g, 12.7 mmol) were mixed in NMP (290 g) and mixed at 80 ° C. with 5 After reacting for a period of time, A-1 (5.57 g, 28.4 mmol) and NMP (93.0 g) were added and reacted at 55 ° C. for 6 hours to obtain a polyamic acid (E) solution (concentration 20.0 mass). %). This polyamic acid (E) had a number average molecular weight of 24,513 and a weight average molecular weight of 79,705.

Comparative Example 2
In the same manner as in Example 3, NMP was added to the polyamic acid (E) solution (75.0 g) obtained in Comparative Example 1 to dilute it to 6% by mass, and then acetic anhydride (15. 55 g) and pyridine (4.82 g) were added and reacted at 100 ° C. for 2 hours. The reaction solution was poured into methanol (946 g), and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C. to obtain a polyimide (F) powder. The imidation ratio of this polyimide (F) was 77%, the number average molecular weight was 19,377 and the weight average molecular weight was 53,171.

NMP56.6g was added to the polyimide (F) powder 11.6g, and it stirred for 30 hours and was made to melt | dissolve at 70 degreeC, and the polyimide (F) solution was obtained.

Comparative Example 3
In the same manner as in Example 4, NMP, an NMP solution of C-1 and BCS were added to the polyimide (F) solution obtained in Comparative Example 2, and the mixture was stirred at 50 ° C. for 20 hours. C-1 was 0.3% by mass, NMP was 48.7% by mass, and BCS was 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Comparative Example 4
NMP, C-2 NMP solution and BCS were added to the polyimide (F) solution obtained in Comparative Example 2, and the mixture was stirred at 50 ° C. for 20 hours. The polyimide was 6% by mass, and C-2 was 0.3% by mass. %, NMP was 48.7% by mass, and BCS was 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Comparative Example 5
NMP and BCS were added to the polyimide (F) solution obtained in Comparative Example 2, and the mixture was stirred to prepare 6% by mass of polyimide, 48.7% by mass of NMP, and 45% by mass of BCS. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Comparative Example 6
To the polyamic acid (E) solution obtained in Comparative Example 1, NMP, an NMP solution of C-2 and BCS were added and stirred, and polyimide was 6% by mass, C-2 was 0.3% by mass, and NMP was 48%. 0.7% by mass and BCS 45% by mass. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Comparative Example 7
NMP and BCS are added to the polyamic acid (E) solution obtained in Comparative Example 1 and stirred so that the polyamic acid (E) is 6% by mass, NMP is 48.7% by mass, and BCS is 45% by mass. Prepared. A liquid crystal aligning agent was obtained by pressure filtration through a membrane filter having a pore diameter of 1 μm.

Table 44 shows liquid crystal aligning agents as examples and liquid crystal aligning agents as comparative examples.

Next, the liquid crystal alignment treatment agents of the above-described examples were evaluated while being compared with the comparative examples. First, the evaluation method will be described.

<Evaluation of solvent resistance>
The solvent resistance was evaluated by examining the remaining film rate after immersion in the solvent. Specifically, a liquid crystal alignment treatment agent is spin-coated on a glass substrate with an ITO electrode, dried on an 80 ° C. hot plate for 5 minutes, and then baked in a hot air circulation oven at 230 ° C. for 30 minutes to obtain a film thickness of 100 nm. The coating film was formed. This substrate with a liquid crystal alignment film was immersed in NMP at 23 ° C. for 1 minute, and the remaining film ratio was determined according to the following formula. In Equation (2), a is the film thickness after immersion, and b is the film thickness before immersion.

Remaining film ratio (%) = (a / b) × 100 (2)

<Evaluation of electrical characteristics and UV resistance>
A liquid crystal aligning agent is spin-coated on a glass substrate with an ITO electrode, dried on a hot plate at 80 ° C. for 5 minutes, and then baked in a hot air circulation oven at 230 ° C. for 30 minutes to form a coating film having a film thickness of 100 Thus, a substrate with a liquid crystal alignment film was obtained. Two substrates with the liquid crystal alignment film were prepared, and a 6 μm spacer was sprayed on one liquid crystal alignment film surface, and then a sealant was printed thereon. Subsequently, after bonding together so that the other board | substrate and the liquid crystal aligning film surface might face each other, the sealing compound was hardened and the empty cell was produced. Liquid crystal MLC-6608 (manufactured by Merck Japan) 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.

The voltage of 1V was applied to the above liquid crystal cell at a temperature of 80 ° C. for 60 μs, the voltage after 50 ms was measured, and how much the voltage was held was calculated as the voltage holding ratio. Further, the liquid crystal cell after the voltage holding ratio measurement was irradiated with UV light (ultraviolet light), and the voltage holding ratio was measured again in the same manner as described above. The irradiation energy was calculated based on the irradiation intensity at 350 nm. The evaluation results are summarized in Table 45.

As shown in the evaluation results of Table 45, the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of the examples all show a high residual film ratio and excellent solvent resistance in the above-mentioned residual film ratio evaluation. I understood. On the other hand, the liquid crystal alignment films obtained from the liquid crystal aligning agent as a comparative example all showed a low residual film ratio, and it was found that the solvent resistance was remarkably inferior compared to the examples.

The results of solvent resistance evaluation using solvents other than NMP are also shown. When the same evaluation as the remaining film rate evaluation using NMP described above using IPA as a solvent and the same evaluation as the remaining film rate evaluation using NMP described above using PGMEA were performed, the liquid crystal of Example The remaining film ratio of the liquid crystal alignment film obtained from the alignment treatment agent was 100% in any case. On the other hand, the remaining film ratio of the liquid crystal alignment film obtained from the liquid crystal aligning agent of the comparative example was 100% in any case.

When the same evaluation as the above-described residual film ratio evaluation using NMP was performed using PGME, the residual film ratio of the liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the example was 100%. Further, the remaining film ratios of the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of Comparative Examples 3 to 5 were 100%. On the other hand, the remaining film ratio of the liquid crystal alignment film of Comparative Example 6 was 30%, and the remaining film ratio of the liquid crystal alignment film of Comparative Example 7 was 5%.

Comparative Examples 6 and 7 are liquid crystal aligning agents containing polyamic acid, and Examples 11 to 13 are also liquid crystal aligning agents containing polyamic acid. When the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of Examples 11 to 13 were evaluated using PGME in the same manner as the remaining film ratio evaluation using NMP described above, the remaining film ratio was 100%. It shows a high value. Therefore, in an Example, even if it comprises a polyamic acid and comprises a liquid-crystal aligning agent, it turns out that high solvent tolerance is shown.

From the above evaluation results, the liquid crystal alignment films obtained from the liquid crystal alignment treatment agents of the examples have very excellent solvent resistance, and their superiority over the prior art is clearly clear especially for solvents with high solubility. It can be seen that it is demonstrated.

Next, electrical characteristics will be described. It can be seen that the liquid crystal cells using the liquid crystal alignment treatment agents of the examples all have a high voltage holding ratio exceeding 90% and are excellent in electrical characteristics.

Regarding the UV resistance, the voltage holding ratio of the liquid crystal cell using the liquid crystal aligning agents of Examples 11 to 13 is a high value exceeding 79% even after UV irradiation. In the example, a very high voltage holding ratio exceeding 90% is shown.

From the above, it can be seen that the liquid crystal cell having the liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the example has excellent electrical characteristics and UV resistance.

On the other hand, in the case of the liquid crystal aligning agent as a comparative example, it can be seen that the voltage holding ratio of the liquid crystal cell after UV irradiation is 70.8% in comparative example 6 and 74.6% in comparative example 7. . It can also be seen that in any of the comparative examples, when the 50 J UV light is irradiated, the voltage holding ratio does not show a high value exceeding 90%.

From the above evaluation results, the liquid crystal alignment film obtained by using the liquid crystal aligning agent from the polyamic acid and polyimide obtained by using the diamine compound of the present invention is excellent in solvent resistance, and the voltage holding ratio is reduced by light irradiation. It can be seen that it can be suppressed.

The liquid crystal alignment film of the present invention has sufficient solvent resistance in the washing step during the manufacturing process of the liquid crystal panel, and also has a liquid crystal alignment film in which a decrease in voltage holding ratio is suppressed even when exposed to light irradiation. The liquid crystal display element has excellent display quality and can be suitably used for a large-screen high-definition liquid crystal television.
The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2010-133337 filed on June 10, 2010 are incorporated herein by reference. Part.

Claims

A liquid crystal aligning agent comprising a polyimide precursor having a cyclocarbonate group and at least one polymer selected from the group consisting of polyimides obtained by imidizing the polyimide precursor.
The liquid crystal aligning agent according to claim 1, wherein the cyclocarbonate group is present at a side chain terminal of the polyimide precursor and the polyimide.
The liquid-crystal aligning agent of Claim 1 or 2 with which the side chain which has the said cyclocarbonate group is represented by following formula [1].

(X 1 is —O—, —NH—, —N (CH 3 ) —, —CONH—, —NHCO—, —CH 2 O—, —COO—, —OCO—, —CON (CH 3 ) — Or N (CH 3 ) CO—, X 2 is an alkylene group having 1 to 5 carbon atoms, and X 3 has a structure represented by the following formula [1a].)
The liquid crystal aligning agent according to any one of claims 1 to 3, wherein the polyimide precursor and the polyimide are polymers made from a diamine compound represented by the following formula [2].

(X 1 is —O—, —NH—, —N (CH 3 ) —, —CONH—, —NHCO—, —CH 2 O—, —COO—, —OCO—, —CON (CH 3 ) — Or N (CH 3 ) CO—, X 2 is an alkylene group having 1 to 5 carbon atoms, X 3 is a structure represented by the following formula [1a], and n is an integer of 1 to 4 is there.)
The liquid crystal aligning agent according to any one of claims 1 to 4, further comprising a base having a primary amino group and a nitrogen-containing heterocyclic ring in the molecular structure.
6. The liquid crystal aligning agent according to claim 5, wherein the base is at least one compound selected from the group consisting of 3-aminopropylimidazole and 3-picolylamine.
7. The liquid crystal according to claim 1, further comprising an organic solvent that dissolves the polyimide precursor and the polyimide, and the organic solvent contains 5 to 80% by mass of a poor solvent in the liquid crystal alignment treatment agent. Alignment treatment agent.
A liquid crystal alignment film obtained from the liquid crystal alignment treatment agent according to any one of claims 1 to 7.
A liquid crystal composition comprising a liquid crystal layer between a pair of substrates provided with electrodes and comprising a polymerizable compound that is polymerized by at least one of active energy rays and heat is disposed between the pair of substrates, and the electrodes The liquid crystal aligning film of Claim 8 used for the liquid crystal display element manufactured through the process of superposing | polymerizing the said polymeric compound, applying a voltage in between.
A liquid crystal display element having the liquid crystal alignment film according to claim 9.
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 polymerizing at least one of active energy rays and heat between the pair of substrates. The liquid crystal display element according to claim 10, wherein the liquid crystal display element is manufactured through a step of polymerizing the polymerizable compound while applying a voltage between the electrodes.
A diamine compound represented by the following formula [2].

(X 1 is —O—, —NH—, —N (CH 3 ) —, —CONH—, —NHCO—, —CH 2 O—, —COO—, —OCO—, —CON (CH 3 ) — Or N (CH 3 ) CO—, X 2 is an alkylene group having 1 to 5 carbon atoms, X 3 is a structure represented by the following formula [1a], and n is an integer of 1 to 4 is there.)
A polyimide precursor obtained by reacting the diamine component containing the diamine compound according to claim 12 and an acid dianhydride component.
The polyimide precursor according to claim 13, wherein the diamine component further contains a diamine compound represented by the following formula [3].

(Y 1 is a single bond, — (CH 2 ) a — (a is an integer of 1 to 10), —O—, —CH 2 O—, —COO—, and —OCO—. Y 2 is a divalent organic group, Y 2 is a single bond or a divalent organic group selected from (CH 2 ) b — (b is an integer of 1 to 10), Y 3 is a single bond, — (CH 2 ) c — (c is an integer of 1 to 10), a divalent organic group selected from the group consisting of —O—, —CH 2 O—, —COO—, and —OCO—. Y 4 is a cyclic group selected from the group consisting of a benzene ring, a cyclohexyl ring and a heterocyclic ring, and an arbitrary hydrogen atom on these cyclic groups is an alkyl group having 1 to 3 carbon atoms, a carbon number 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 fluorine Is a divalent organic group selected from an organic group having a carbon number of 12-25 with substituted by 2 may be a monovalent organic group, or steroid skeleton atom .Y 5 is cyclohexyl ring a benzene ring, cyclohexane And a cyclic group selected from the group consisting of heterocyclic rings, wherein any hydrogen atom on the cyclic group is an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, or 1 to 3 carbon atoms. A fluorine-containing alkyl group, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a divalent organic group which may be substituted with a fluorine atom, n is an integer of 0 to 4. Y 6 is a carbon number 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, and m is an integer of 1 to 4. .)
The polyimide precursor according to claim 13 or 14, wherein the acid dianhydride component is a tetracarboxylic dianhydride represented by the following formula [4].

(Z 1 is a tetravalent organic group having 4 to 13 carbon atoms and has a non-aromatic cyclic hydrocarbon group having 4 to 10 carbon atoms.)
16. The liquid crystal aligning agent according to claim 15, wherein Z 1 in the tetracarboxylic dianhydride is an organic group having a structure of any one of the following formulas [4a] to [4j].

(In Formula [4a], Z 2 to Z 5 are each independently a group selected from a hydrogen atom, a methyl group, a chlorine atom, or a benzene ring. In Formula [4g], Z 6 and Z 7 are And each independently represents a hydrogen atom or a methyl group.)
A polyimide obtained by dehydrating and ring-closing the polyimide precursor according to any one of claims 13 to 15.