JP6143014B2 - Polymer, liquid crystal aligning agent, liquid crystal aligning film, liquid crystal display element, and diamine - Google Patents

Description

  The present invention relates to a polyimide precursor, polyimide and polyamide, a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element, and a diamine.

  In the liquid crystal display element, the liquid crystal alignment film plays a role of aligning the liquid crystal in a certain direction. Currently, the main liquid crystal alignment films that are used industrially are polyimide precursors such as polyamic acid (also called polyamic acid), polyamic acid esters, and polyimide-based liquid crystal aligning agents composed of polyimide solutions. It is manufactured by applying and forming a film. When the liquid crystal is aligned in parallel or inclined with respect to the substrate surface, a surface stretching process is further performed by rubbing after film formation. As an alternative to the rubbing treatment, a method using an anisotropic photochemical reaction by irradiation with polarized ultraviolet rays or the like has been proposed, and in recent years, studies for industrialization have been performed.

  In order to improve the display characteristics of such liquid crystal display elements, methods such as changing the structure of polyamic acid, polyamic acid ester and polyimide, polyamic acid with different characteristics, blend of polyamic acid ester and polyimide, adding additives, etc. As a result, improvements in liquid crystal alignment and electrical characteristics, control of the pretilt angle, and the like are performed. For example, in order to obtain a liquid crystal aligning agent that has excellent electrical characteristics and does not deteriorate the liquid crystal alignment performance even when used under high temperature conditions for a long time, it is possible to obtain a liquid crystal aligning agent having a specific structure group. It has been proposed to use coalescence (see Patent Document 1).

JP 2011-100099 A

  However, as liquid crystal display elements have higher performance, larger area, and power saving of display devices, the characteristics required for liquid crystal alignment films have become stricter, and the liquid crystal display elements are resistant to backlight exposure. Is also required. In particular, a liquid crystal alignment film formed by a method using an anisotropic photochemical reaction by irradiation with polarized ultraviolet rays using a conventional liquid crystal aligning agent, that is, a method of performing an alignment treatment by light irradiation, is an unreacted photoreactive property. There is a problem that the liquid crystal alignment performance deteriorates because the group exists in the liquid crystal alignment film or is exposed to the backlight of the liquid crystal display element.

  An object of the present invention is to solve the above-described problems of the prior art, and an object thereof is to provide a liquid crystal alignment film in which deterioration of liquid crystal alignment performance due to a backlight is suppressed. That is, it aims at providing the polyimide precursor which has such a characteristic, a polyimide, and polyamide, and also providing the liquid crystal aligning agent using the same, a liquid crystal display element, and diamine.

  As a result of intensive studies, the present inventors have found that a polyimide precursor having a structure represented by the following formula [I] in the side chain, a liquid crystal aligning agent containing polyimide or polyamide is extremely suitable for achieving the above-mentioned object. As a result, the present invention has been found to be effective.

That is, the present invention has the following gist.
1. A polymer comprising at least one selected from a polyimide precursor having a structure represented by the following formula [I] as a side chain, a polyimide obtained by imidizing the polyimide precursor, and polyamide.

（式中、Ｙ^１は原子数が５または６の単環式環、原子数が５または６の２つの隣接する単環式環、原子数が８〜１０の二環式の環系、または原子数が１３または１４の三環式の環系から選択される、非置換または置換の、炭素環式または複素環式の２価の芳香族基であり、Ｙ^２は、単結合または、エーテル結合、エステル結合、アミド結合およびウレタン結合からなる群より選択される２価の結合基であり、Ｙ^３は、水素原子がフッ素原子に置換されていてもよい炭素数３〜２０の直鎖状アルキル基または炭素数４〜４０の脂環式骨格を有する１価の有機基である。）

Wherein Y ¹ is a monocyclic ring having 5 or 6 atoms, two adjacent monocyclic rings having 5 or 6 atoms, a bicyclic ring system having 8 to 10 atoms, or An unsubstituted or substituted carbocyclic or heterocyclic divalent aromatic group selected from 13 or 14 tricyclic ring systems, wherein Y ² is a single bond or an ether A divalent linking group selected from the group consisting of a bond, an ester bond, an amide bond and a urethane bond, and Y ³ is a straight chain of 3 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom It is a monovalent organic group having an alkyl group or an alicyclic skeleton having 4 to 40 carbon atoms.)

（式中、Ｙ^１は原子数が５または６の単環式環、原子数が５または６の２つの隣接する単環式環、原子数が８〜１０の二環式の環系、または原子数が１３または１４の三環式の環系から選択される、非置換または置換の、炭素環式または複素環式の２価の芳香族基であり、Ｙ^２は、単結合または、エーテル結合、エステル結合、アミド結合およびウレタン結合からなる群より選択される２価の結合基であり、Ｙ^３は、水素原子がフッ素原子に置換されていてもよい炭素数３〜２０の直鎖状アルキル基または炭素数４〜４０の脂環式骨格を有する１価の有機基であり、Ｙ^４は単結合、メチレン基または炭素数２〜６のアルキレン基であり、Ｙ^５は、単結合、酸素原子、＊−ＯＣＯ−または−ＣＨ_２Ｏ−＊（ただし、「＊」を付した結合手がＹ^４と結合する。）である。ただし、Ｙ^４が単結合であるときＹ^５は単結合である。）2. 2. The polymer according to 1, which is obtained using a diamine represented by the following formula (1).

Wherein Y ¹ is a monocyclic ring having 5 or 6 atoms, two adjacent monocyclic rings having 5 or 6 atoms, a bicyclic ring system having 8 to 10 atoms, or An unsubstituted or substituted carbocyclic or heterocyclic divalent aromatic group selected from 13 or 14 tricyclic ring systems, wherein Y ² is a single bond or an ether A divalent linking group selected from the group consisting of a bond, an ester bond, an amide bond and a urethane bond, and Y ³ is a straight chain of 3 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom An alkyl group or a monovalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms, Y ⁴ is a single bond, a methylene group or an alkylene group having 2 to 6 carbon atoms, Y ⁵ is a single bond, Oxygen atom, * —OCO— or —CH ₂ O— * (however, the bond with “*” is Y ⁴ is a single bond.) However, when Y ⁴ is a single bond, Y ⁵ is a single bond.

3. A liquid crystal aligning agent comprising the polymer described in 1 or 2 above.

A liquid crystal alignment film obtained using the liquid crystal aligning agent according to 4.3.

A liquid crystal display element comprising the liquid crystal alignment film according to 5.4.

（式中、Ｙ^１は原子数が５または６の単環式環、原子数が５または６の２つの隣接する単環式環、原子数が８〜１０の二環式の環系、または原子数が１３または１４の三環式の環系から選択される、非置換または置換の、炭素環式または複素環式の２価の芳香族基であり、Ｙ^２は、単結合または、エーテル結合、エステル結合、アミド結合およびウレタン結合からなる群より選択される２価の結合基であり、Ｙ^３は、水素原子がフッ素原子に置換されていてもよい炭素数３〜２０の直鎖状アルキル基または炭素数４〜４０の脂環式骨格を有する１価の有機基であり、Ｙ^４は単結合、メチレン基または炭素数２〜６のアルキレン基であり、Ｙ^５は、単結合、酸素原子、＊−ＯＣＯ−または−ＣＨ_２Ｏ−＊（ただし、「＊」を付した結合手がＹ^４と結合する。）である。ただし、Ｙ^４が単結合であるときＹ^５は単結合である。）6). A diamine represented by the following formula (1):

Wherein Y ¹ is a monocyclic ring having 5 or 6 atoms, two adjacent monocyclic rings having 5 or 6 atoms, a bicyclic ring system having 8 to 10 atoms, or An unsubstituted or substituted carbocyclic or heterocyclic divalent aromatic group selected from 13 or 14 tricyclic ring systems, wherein Y ² is a single bond or an ether A divalent linking group selected from the group consisting of a bond, an ester bond, an amide bond and a urethane bond, and Y ³ is a straight chain of 3 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom An alkyl group or a monovalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms, Y ⁴ is a single bond, a methylene group or an alkylene group having 2 to 6 carbon atoms, Y ⁵ is a single bond, Oxygen atom, * —OCO— or —CH ₂ O— * (however, the bond with “*” is Y ⁴ is a single bond.) However, when Y ⁴ is a single bond, Y ⁵ is a single bond.

  ADVANTAGE OF THE INVENTION According to this invention, the novel polyimide precursor, polyimide, and polyamide which can obtain the liquid crystal aligning film by which deterioration of the liquid crystal alignment performance by the backlight was suppressed can be provided. And since this liquid crystal aligning film is hard to deteriorate liquid crystal aligning performance even if it exposes to a backlight, the liquid crystal display element which has this liquid crystal aligning film has an effect that it is excellent in display characteristics for a long period of time. In addition, this liquid crystal alignment film suppresses the deterioration of the liquid crystal alignment performance due to AC driving and hardly causes image sticking.

The present invention is described in detail below.
The polymer of the present invention includes a polyimide precursor having a structure represented by the above formula [I] as a side chain, a polyimide having a structure represented by the above formula [I] as a side chain, and the above formula [I]. Is a polyamide having a structure represented by The polyimide precursor is polyamic acid, polyamic acid ester, or the like. The structure represented by the above formula [I] may be directly bonded to a polyimide precursor such as polyamic acid or polyamic acid ester, a main chain of polyimide or polyamide, that is, polyamic acid skeleton, polyimide skeleton or polyimide skeleton. Further, they may be bonded via an appropriate bonding group.

In Formula [I], Y ¹ is a monocyclic ring having 5 or 6 atoms, two adjacent monocyclic rings having 5 or 6 atoms, and having 8 to 10 atoms, as described above. An unsubstituted or substituted carbocyclic or heterocyclic divalent aromatic group selected from a bicyclic ring system or a tricyclic ring system having 13 or 14 atoms. Examples of the monocyclic ring having 5 or 6 atoms include a benzene ring and a pyridine ring. Examples of two adjacent monocyclic rings having 5 or 6 atoms include biphenyl. Examples of the bicyclic ring system having 8 to 10 atoms include naphthalene. Examples of the tricyclic ring system having 13 or 14 atoms include anthracene and fluorene. And as above-mentioned, as for these, the hydrogen atom may be substituted by the C1-C4 alkyl group, the alkoxyl group, a halogen, etc., for example. Y ² represents a single bond or an ether bond (—O—), an ester bond (—COO— or —OCO—), an amide bond (—CONH— or —NHCO—) and a urethane bond (—NHCOO— or —OCONH—). Is a divalent linking group selected from the group consisting of: Y ³ is a monovalent organic group having a C 3-20 linear alkyl group or a C 4-40 alicyclic skeleton in which a hydrogen atom may be substituted with a fluorine atom. Preferably, Y ¹ is a phenylene group or divalent naphthalene (—C ₁₀ H ₆ —), Y ² is a single bond or an ether bond, and Y ³ is a cyclohexyl group or a bicyclohexyl group.

  A liquid crystal alignment film formed using a liquid crystal aligning agent containing a polyimide precursor such as polyamic acid and polyamic acid ester having a structure represented by the above formula [I] as a side chain, polyamic acid ester, and polyamide, Deterioration of the liquid crystal alignment performance due to backlight irradiation is suppressed. Specifically, using a polyamic acid having a structure represented by the formula [I] as a side chain, a polyimide precursor such as a polyamic acid ester, a liquid crystal aligning agent containing polyimide or polyamide, irradiation with polarized ultraviolet rays, etc. As a liquid crystal alignment film (also referred to as “photo-alignment film”) formed by a method using an anisotropic photochemical reaction due to light irradiation, that is, a method of aligning treatment by light irradiation, the liquid crystal alignment performance deteriorates due to backlight irradiation. It will be suppressed. Therefore, the liquid crystal display element having the liquid crystal alignment film has an effect of being excellent in display characteristics for a long time because the liquid crystal alignment performance is good even when used for a long time. In addition, a liquid crystal alignment film formed using a polyimide precursor, polyimide or polyamide having a structure represented by the above formula [I] as a side chain is driven by applying AC (alternating current) for a long time, The deterioration of the liquid crystal alignment performance is suppressed. Therefore, the liquid crystal display element having the liquid crystal alignment film is less likely to be burned even when driven with AC for a long time.

  The effect that the deterioration of the liquid crystal alignment performance due to such backlight irradiation is suppressed is that the structure represented by the above formula [I] of the present invention has an oxyacrylate group and has an absorption maximum in the vicinity of 313 nm. This is presumably because there is no group having an absorption maximum in the ultraviolet region of a relatively long wavelength, such as a cinnamoyl group having. On the other hand, when a conventional liquid crystal aligning agent, for example, a structure having a cinnamoyl group as in Patent Document 1 is used instead of an oxyacrylate group, a cinnamoyl group that is an unreacted photoreactive group of the liquid crystal alignment film However, the liquid crystal alignment performance is greatly deteriorated due to the irradiation of the backlight because the light from the backlight reacts in the liquid crystal alignment film to disturb the alignment of the liquid crystal.

  In addition, the effect of suppressing deterioration of the liquid crystal alignment performance even when AC driving for a long period of time is that the structure represented by the above formula [I] has a relatively long chain alkyl group and a ring structure, and has a high verticality. This is presumed to have alignment performance.

  The polyimide precursor having the structure represented by the formula [I] as a side chain according to the present invention includes, for example, a diamine component containing a diamine having the structure represented by the formula [I] as a side chain, and a tetracarboxylic acid. It is obtained by reacting the components. In addition, polyamic acid ester is obtained also by the method of converting the carboxyl group of polyamic acid into ester. The polyimide precursor of the present invention can also be obtained by reacting a tetracarboxylic acid component having a structure represented by the above formula [I] as a side chain with a diamine component. And the polyimide which has the structure represented by the said Formula [I] of this invention as a side chain by imidating polyimide precursors, such as these polyamic acid or polyamic acid ester, is obtained. The polyamide having a structure represented by the above formula [I] as a side chain of the present invention comprises a diamine component containing a diamine having a structure represented by the above formula [I] as a side chain and a dicarboxylic acid halide. It is obtained by reacting in the presence of a base or by reacting a diamine component containing a diamine having the structure represented by the above formula [I] as a side chain with a dicarboxylic acid in the presence of an appropriate condensing agent or base. It is done. The polyamide of the present invention is obtained by reacting a dicarboxylic acid halide having a structure represented by the above formula [I] as a side chain with a diamine component in the presence of a base, or represented by the above formula [I]. It can also be obtained by reacting a dicarboxylic acid having a structure as a side chain with a diamine component in the presence of a suitable condensing agent and base. Any of polyimide precursors such as polyamic acid and polyamic acid ester, polyimide, and polyamide are useful as a polymer for obtaining a liquid crystal alignment film. In addition, the diamine having a structure represented by the formula [I] contained in the diamine component as a side chain may be one kind or two or more kinds, and the diamine component has a structure represented by the formula [I] on the side. One kind or two or more kinds of other diamines other than the diamine having a chain may be contained. Further, the tetracarboxylic acid component or dicarboxylic acid having the structure represented by the formula [I] as a side chain may be one kind or two or more kinds, and the structure represented by the formula [I] is used as a side chain. One kind or two or more kinds of other tetracarboxylic acids and dicarboxylic acids other than the tetracarboxylic acid component and dicarboxylic acid that are contained may be included.

Examples of the diamine having the structure represented by the formula [I] as a side chain include the diamine represented by the formula (1). In addition, the diamine represented by the above formula (1) is a novel compound not described in any literature. In Formula (1), Y ¹ , Y ² and Y ³ are the same as Y ¹ , Y ² and Y ³ in Formula [I], respectively. Y ⁴ is a single bond, a methylene group or an alkylene group having 2 to 6 carbon atoms. Y ⁵ is a single bond, an oxygen atom, * —OCO— or —CH ₂ O— * (where a bond marked with “*” is bonded to Y ⁴ ). Incidentally, Y ⁵ is a single bond when Y ⁴ is a single bond. In Formula (1), Y ¹ is preferably a phenylene group or divalent naphthalene (—C ₁₀ H ₆ —), Y ² is a single bond or an ether bond, and Y ³ is a cyclohexyl group or bicyclohexyl. Y ⁴ is a single bond, and Y ⁵ is a single bond or —CH ₂ O—.

  Further, in the formula (1), the position of the amino group is not particularly limited, and is not particularly limited as long as it is a diamine. From the viewpoint of liquid crystal alignment and ease of synthesis, for example, for each oxyacrylate group, , 2, 3 position, 2, 4 position, 2, 5 position, 2, 6 position, 3, 4 position or 3, 5 position on the benzene ring. Among these, from the viewpoint of reactivity when synthesizing the polymer, the 2,4 position, the 2,5 position, or the 3,5 position is preferable.

Specific examples of the diamine represented by the formula (1) include the following diamines.

  The method for synthesizing the diamine represented by the above formula (1) is not particularly limited, and can be produced, for example, according to the synthesis examples described later. For example, the diamine represented by the formula (1) can be obtained by synthesizing a corresponding dinitro compound represented by the following formula (1 '), further reducing the nitro group and converting it to an amino group. The method for reducing the dinitro compound is not particularly limited, and usually palladium-carbon, platinum oxide, Raney nickel, iron, tin chloride, platinum black, rhodium-alumina, platinum carbon sulfide, etc. can be used as a catalyst. From the viewpoint of selectively reducing only the nitro group in a high yield while leaving no reduction, it is effective to use a chemical reduction method using iron or tin chloride. Examples of the solvent include alcohol-based solvents such as ethyl acetate, toluene, tetrahydrofuran, dioxane and methanol, and examples of the reducing agent include reactions using hydrogen gas, hydrazine, hydrogen chloride, ammonium chloride and the like.

（式中、Ｙ^１、Ｙ^２、Ｙ^３、Ｙ^４、Ｙ^５は、それぞれ式（１）におけるＹ^１、Ｙ^２、Ｙ^３、Ｙ^４、Ｙ^５と同じである。）

^{(Wherein, Y 1, Y 2, Y 3} , Y 4, Y 5 is the same as ^{Y 1, Y 2, Y 3} , Y 4, Y 5 in each formula (1).)

  The method for synthesizing the dinitro compound represented by the formula (1 ′) is not particularly limited and can be synthesized by any method. Specific examples thereof include, for example, the method shown in the following reaction. be able to.

  In this reaction, the dinitro compound A and the compound B having a hydroxyl group are reacted with DABCO (1,4-diazabicyclo [2.2.2] in an organic solvent such as ethyl acetate, toluene, tetrahydrofuran, dioxane, chloroform, or dichloromethane. It can be synthesized by reacting with a basic catalyst such as octane) or DMAP (4-N, N-dimethylaminopyridine).

In the dinitro compound A, Y ⁴ and Y ⁵ are the same as Y ⁴ and Y ⁵ in Formula (1), respectively, and the structure is not particularly limited as long as it has an alkyne structure at the side chain end. Further, in the compound B having the hydroxyl ^group, Y ^1, Y 2, ^{Y 3} are the same as ^{Y 1,} Y 2, ^{Y 3} in each formula (1), for example, there may be mentioned phenols and derivatives thereof, especially It is not limited.

  The diamine represented by the above formula (1) can exhibit the effects of the present invention at 10 mol% or more with respect to the total amount of the diamine component, but is preferably 30 to 100 mol%, more preferably 50. ˜100 mol%. In the present specification, unless otherwise specified, the ratio is based on the number of moles.

  Moreover, as other diamine other than the diamine represented by Formula (1), the diamine represented by following formula (2) is mentioned.

（式（２）中、Ｒ^２は単結合、−Ｏ−又は二価の有機基であり、Ｘ^２、Ｘ^３、Ｘ^４はそれぞれ独立して二価のベンゼン環又はシクロヘキサン環であり、ｐ、ｑ、ｒはそれぞれ独立して０又は１の整数であり、Ｒ^３は、水素原子、炭素数１〜２２のアルキル基又はステロイド骨格を有する炭素数１２〜２５の１価の有機基である。）

(In Formula (2), R ² is a single bond, —O— or a divalent organic group, X ² , X ³ and X ⁴ are each independently a divalent benzene ring or a cyclohexane ring; , Q, and r are each independently an integer of 0 or 1, and R ³ is a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or a monovalent organic group having 12 to 25 carbon atoms having a steroid skeleton. .)

In formula (2), R ² is preferably an ether bond, an ester bond, an amide bond or a urethane bond. R ³ is preferably an alkyl group having 12 to 18 carbon atoms. The alkyl group having 1 to 22 carbon atoms may be linear or branched.

  The diamine represented by the formula (2) contributes to increasing the pretilt angle of the liquid crystal (the tilt angle of the liquid crystal with respect to the liquid crystal alignment film), and includes a long-chain alkyl group, a perfluoroalkyl group, and an aromatic cyclic group. And a diamine having an aliphatic cyclic group, a substituent combining these, a steroid skeleton group, and the like.

  It is preferable that the diamine represented by Formula (2) is 5-50 mol% with respect to the diamine component whole quantity, More preferably, it is 10-30 mol%.

  Other diamines other than the diamine represented by the above formula (1) include p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, and 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-diamino Phenol, 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'-diamino Phenyl, 3,3′-dicarboxy-4,4′-diaminobiphenyl, 3,3′-difluoro-4,4′-biphenyl, 3,3′-trifluoromethyl-4,4′-diaminobiphenyl, 3, , 4′-diaminobiphenyl, 3,3′-diaminobiphenyl, 2,2′-diaminobiphenyl, 2,3′-diaminobiphenyl, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 3,4 '-Diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'- Diaminodiphenyl ether, 2,3′-diaminodiphenyl ether, 4,4 -Sulfonyldianiline, 3,3'-sulfonyldianiline, bis (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, dimethyl-bis (3-amino Phenyl) 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′-diaminobenzophenone, 3,3′-diaminobenzophenone, 3,4′-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2′-diaminobenzophenone, 2,3′-diamino Benzophenone, 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, -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-phenylene Bis (methylene)] dianiline, 3,4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,3 ′-[1,4-phenylenebis (methylene)] dianiline, 3,3 -[1,3-phenylenebis (methylene)] dianiline, 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis [(3-aminophenyl) methanone], 1,3- Phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [(3-aminophenyl) methanone], 1,4-phenylenebis (4-aminobenzoate), 1,4-phenylenebis (3- Aminobenzoate), 1,3-phenylenebis (4-aminobenzoate), 1,3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis ( 4-aminophenyl) 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-amino) Benzamide), 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-aminophene) Xyl) phenyl] hexafluoropropane, 2,2′-bis (4-aminophenyl) hexafluoropropane, 2,2′-bis (3-aminophenyl) hexafluoropropane, 2,2′-bis (3-amino) -4-methylphenyl) hexafluoropropane, 2,2'-bis (4-aminophenyl) propane, 2,2'-bis (3-aminophenyl) propane, 2,2'-bis (3-amino-4) -Methylphenyl) propane, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bi (4-aminophenoxy) hexane, 1,6-bis (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- (3-aminophenoxy) heptane, 1, 8-bis (4-aminophenoxy) octane, 1,8-bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10- (4-aminophenoxy) decane, 1,10- (3-aminophenoxy) decane, 1,11- (4-aminophenoxy) undecane, 1,11- (3-aminophenoxy) undecane, 12- (4-aminophenoxy) dodecane, 1,12- (3-aminophenoxy) dodecane, 4- (aminomethyl) aniline, 3- (aminomethyl) ani Aromatic diamines such as phosphorus, 3-((aminomethyl) methyl) aniline, 4- (2-aminoethyl) aniline or 3- (2-aminoethylaniline), bis (4-aminocyclohexyl) methane or bis (4 -Amino-3-methylcyclohexyl) alicyclic diamine such as methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diamino Also included are aliphatic diamines such as heptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane or 1,12-diaminododecane.

  The above-mentioned other diamines can be used alone or in combination of two or more depending on the properties such as liquid crystal orientation, voltage holding ratio, and accumulated charge when the liquid crystal alignment film is used.

  The tetracarboxylic acid component is at least one selected from tetracarboxylic acids and tetracarboxylic acid derivatives. Examples of the tetracarboxylic acid derivative include tetracarboxylic acid dihalide, tetracarboxylic dianhydride, tetracarboxylic acid diester dichloride, and tetracarboxylic acid diester. For example, a polyamic acid can be obtained by reacting a diamine component with a tetracarboxylic acid dihalide, tetracarboxylic dianhydride, or the like. In addition, a polyamic acid ester can be obtained by reacting a tetracarboxylic acid diester dichloride with a diamine component or reacting a tetracarboxylic acid diester with a diamine component in the presence of a suitable condensing agent or base. The tetracarboxylic acid component may be one type or two or more types.

  Examples of the tetracarboxylic acid component include a tetracarboxylic dianhydride represented by the following formula (3).

（式（３）中、Ｚ_１は炭素数４〜６の非芳香族環状炭化水素基を含有する炭素数４〜１３の４価の有機基である。）

(In the formula (3), _{Z 1} is a tetravalent organic group having 4 to 13 carbon atoms which contains a non-aromatic cyclic hydrocarbon group having 4 to 6 carbon atoms.)

In formula (3), specific examples of Z ₁ include tetravalent organic groups represented by the following formulas (3a) to (3j).

（式（３ａ）中、Ｚ_２〜Ｚ_５は水素原子、メチル基、塩素原子またはベンゼン環であり、それぞれ、同じであっても異なってもよく、式（３ｇ）中、Ｚ_６およびＺ_７は水素原子またはメチル基であり、それぞれ、同じであっても異なってもよい。）

(In the formula (3a), Z _{2 to} Z ₅ are a hydrogen atom, a methyl group, a chlorine atom or a benzene ring, and may be the same or different. In the formula (3g), Z ₆ and Z ₇ Are hydrogen atoms or methyl groups, which may be the same or different.

In formula (3), particularly preferred structure of Z ₁ is represented by formula (3a), formula (3c), formula (3d), formula (3e), formula (3f) or formula because of polymerization reactivity and ease of synthesis. (3g). Among these, the formula (3a), the formula (3e), the formula (3f), or the formula (3g) is preferable.

  Moreover, the ratio of the tetracarboxylic dianhydride shown by Formula (3) with respect to the tetracarboxylic acid component whole quantity is not specifically limited, For example, the tetracarboxylic dianhydride whose tetracarboxylic acid component is shown by the said Formula (3) It may be only. Of course, the tetracarboxylic acid component may contain a tetracarboxylic acid or a tetracarboxylic acid derivative other than the tetracarboxylic dianhydride represented by the formula (3) as long as the effects of the present invention are not impaired. In that case, it is preferable that 1 mol% or more of the total amount of the tetracarboxylic acid component is the tetracarboxylic dianhydride represented by the above formula (3), more preferably 5 mol% or more, and still more preferably 10 mol%. That's it.

  Other tetracarboxylic dianhydrides other than the tetracarboxylic dianhydride represented by the above formula (3) include pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6 -Naphthalene tetracarboxylic acid, 1,4,5,8-naphthalene tetracarboxylic acid, 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic 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-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4- Dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3,4-dicarboxyphenyl) pyridine, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic Acid, 3,4,9,10-perylenetetracarboxylic acid or 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid.

Tetracarboxylic acid diesters are not particularly limited. Specific examples are given below.
Specific examples of the aliphatic tetracarboxylic acid diester include 1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1 , 3-Dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid dialkyl ester, 1,2, 3,4-cyclopentanetetracarboxylic acid dialkyl ester, 2,3,4,5-tetrahydrofurantetracarboxylic acid dialkyl ester, 1,2,4,5-cyclohexanetetracarboxylic acid dialkyl ester, 3,4-dicarboxy-1 -Cyclohexyl succinic acid dialkyl ester, 3,4-dicarboxy- , 2,3,4-Tetrahydro-1-naphthalene succinic acid dialkyl ester, 1,2,3,4-butanetetracarboxylic acid dialkyl ester, bicyclo [3,3,0] octane-2,4,6,8- Tetracarboxylic acid dialkyl ester, 3,3 ′, 4,4′-dicyclohexyltetracarboxylic acid dialkyl ester, 2,3,5-tricarboxycyclopentylacetic acid dialkyl ester, cis-3,7-dibutylcycloocta-1,5- Diene-1,2,5,6-tetracarboxylic acid dialkyl ester, tricyclo [4.2.1.0 ^2,5 ] nonane-3,4,7,8-tetracarboxylic acid-3, 4: 7,8 A dialkyl ester, hexacyclo [6.6.0.1 ^2,7 . 0 ^3,6 . 1 ^9,14 . 0 ^10,13] hexadecane -4,5,11,12- tetracarboxylic acid-4,5: 11,12-dialkyl ester, 4- (2,5-di-oxo-tetrahydrofuran-3-yl) -1,2, Examples include 3,4-tetrahydronaphthalene-1,2-dicarboxylic dialkyl ester.

  As the aromatic tetracarboxylic acid dialkyl ester, pyromellitic acid dialkyl ester, 3,3 ′, 4,4′-biphenyltetracarboxylic acid dialkyl ester, 2,2 ′, 3,3′-biphenyltetracarboxylic acid dialkyl ester, 2,3,3 ′, 4-biphenyltetracarboxylic acid dialkyl ester, 3,3 ′, 4,4′-benzophenone tetracarboxylic acid dialkyl ester, 2,3,3 ′, 4-benzophenone tetracarboxylic acid dialkyl ester, bis (3,4-dicarboxyphenyl) ether dialkyl ester, bis (3,4-dicarboxyphenyl) sulfone dialkyl ester, 1,2,5,6-naphthalene tetracarboxylic acid dialkyl ester, 2,3,6,7- Naphthalene tetracarboxylic acid dialkyl ester And the like.

  There are no particular limitations on the dicarboxylic acid that is reacted with the diamine component to obtain the polyamide of the present invention. Specific examples of the dicarboxylic acid or its derivative aliphatic dicarboxylic acid to be reacted with the diamine component to obtain polyamide include malonic acid, succinic acid, dimethylmalonic acid, succinic acid, fumaric acid, glutaric acid, adipic acid, muconic acid, 2 -Dicarboxylic acids such as methyladipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid and suberic acid.

  Examples of the alicyclic dicarboxylic acid include 1,1-cyclopropanedicarboxylic acid, 1,2-cyclopropanedicarboxylic acid, 1,1-cyclobutanedicarboxylic acid, 1,2-cyclobutanedicarboxylic acid, and 1,3-cyclobutanedicarboxylic acid. Acid, 3,4-diphenyl-1,2-cyclobutanedicarboxylic acid, 2,4-diphenyl-1,3-cyclobutanedicarboxylic acid, 1-cyclobutene-1,2-dicarboxylic acid, 1-cyclobutene-3,4-dicarboxylic acid Acid, 1,1-cyclopentanedicarboxylic acid, 1,2-cyclopentanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,1-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexane Dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,4- (2-norbo Nene) dicarboxylic acid, norbornene-2,3-dicarboxylic acid, bicyclo [2.2.2] octane-1,4-dicarboxylic acid, bicyclo [2.2.2] octane-2,3-dicarboxylic acid, 2, 5-dioxo-1,4-bicyclo [2.2.2] octanedicarboxylic acid, 1,3-adamantane dicarboxylic acid, 4,8-dioxo-1,3-adamantane dicarboxylic acid, 2,6-spiro [3. 3] Heptanedicarboxylic acid, 1,3-adamantanediacetic acid, camphoric acid and the like can be mentioned.

  As aromatic dicarboxylic acids, o-phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tert-butylisophthalic acid, 5-aminoisophthalic acid, 5-hydroxyisophthalic acid, 2,5-dimethylterephthalic acid Acid, tetramethylterephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,4-anthracenedicarboxylic acid, 1,4 -Anthraquinone dicarboxylic acid, 2,5-biphenyl dicarboxylic acid, 4,4'-biphenyl dicarboxylic acid, 1,5-biphenylene dicarboxylic acid, 4,4 "-terphenyl dicarboxylic acid, 4,4'-diphenylmethane dicarboxylic acid, 4 , 4′-Diphenylethanedicarboxylic acid, 4,4′-diphenyl Rupropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-bibenzyldicarboxylic acid, 4,4'-stilbene dicarboxylic acid, 4,4'- Transdicarboxylic acid, 4,4′-carbonyldibenzoic acid, 4,4′-sulfonyldibenzoic acid, 4,4′-dithiodibenzoic acid, p-phenylenediacetic acid, 3,3′-p-phenylenedipropion Acid, 4-carboxycinnamic acid, p-phenylenediacrylic acid, 3,3 ′-[4,4 ′-(methylenedi-p-phenylene)] dipropionic acid, 4,4 ′-[4,4 ′-( Oxydi-p-phenylene)] dipropionic acid, 4,4 ′-[4,4 ′-(oxydi-p-phenylene)] butyric acid, (isopropylidenedi-p-phenylenedioxy) Can be exemplified a two-butyric acid, bis (p- carboxyphenyl) dicarboxylic acids such as dimethyl silane.

  Examples of the dicarboxylic acid containing a heterocyclic ring include 1,5- (9-oxofluorene) dicarboxylic acid, 3,4-furandicarboxylic acid, 4,5-thiazole dicarboxylic acid, 2-phenyl-4,5-thiazole dicarboxylic acid, 1,2,5-thiadiazole-3,4-dicarboxylic acid, 1,2,5-oxadiazole-3,4-dicarboxylic acid, 2,3-pyridinedicarboxylic acid, 2,4-pyridinedicarboxylic acid, 2, Examples thereof include 5-pyridinedicarboxylic acid, 2,6-pyridinedicarboxylic acid, 3,4-pyridinedicarboxylic acid, and 3,5-pyridinedicarboxylic acid.

  The various dicarboxylic acids may be acid dihalides or those having an anhydrous structure. Among these, terephthalic acid, isoterephthalic acid, 1,4-cyclohexanedicarboxylic acid, 4,4′-biphenyldicarboxylic acid, 4,4′-diphenylmethanedicarboxylic acid, 4,4′-diphenylethanedicarboxylic acid, 4,4 '-Diphenylpropanedicarboxylic acid, 4,4'-diphenylhexafluoropropanedicarboxylic acid, 2,2-bis (phenyl) propanedicarboxylic acid, 4,4 "-terphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 2 , 5-pyridinedicarboxylic acid or these acid dihalides, etc. Some of these compounds have isomers, but may be a mixture containing them. You may use together.

  The tetracarboxylic dianhydride represented by the above formula (3), other tetracarboxylic acids and tetracarboxylic acid derivatives, dicarboxylic acids, and the like are liquid crystal alignment properties, voltage holding ratios, accumulated charges, etc. when used as liquid crystal alignment films. Depending on the desired characteristics, one kind or a mixture of two or more kinds may be used.

  The reaction of the diamine component and the tetracarboxylic acid component is usually performed in an organic solvent. The organic solvent used at that time is not particularly limited as long as the generated polyimide precursor such as polyamic acid dissolves. Specific examples 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 Nobutyl 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, pyruvate Ethyl, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-metho Shipuropion 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. Furthermore, even if it is a solvent which does not dissolve a polyimide precursor, you may mix and use the said solvent in the range which the produced | generated polyimide precursor does not precipitate. Moreover, since the water | moisture content in an organic solvent inhibits a polymerization reaction, and also causes the produced polyimide precursor to hydrolyze, it is preferable to use what dehydrated and dried the organic solvent.

  When the diamine component and the tetracarboxylic acid component are reacted in an organic solvent, the solution in which the diamine component is dispersed or dissolved in the organic solvent is stirred, and the tetracarboxylic acid component is dispersed or dissolved in the organic solvent as it is. And a method of adding a diamine component to a solution obtained by dispersing or dissolving a tetracarboxylic acid component in an organic solvent, a method of alternately adding a tetracarboxylic acid component and a diamine component, and the like. Any of these methods may be used. In addition, when reacting using a plurality of diamine components or tetracarboxylic acid components, they may be reacted in a premixed state, individually or sequentially, or further individually reacted low molecular weight substances. May be mixed and reacted. Although the polymerization temperature in that case can select the arbitrary temperature of -20 degreeC-150 degreeC, Preferably it is the range of -5 degreeC-100 degreeC. The reaction can be carried out at any concentration, but if the concentration is too low, it is difficult to obtain a high molecular weight polyimide precursor (and thus polyimide), and if the concentration is too high, the viscosity of the reaction solution becomes too high. Uniform stirring becomes difficult. Therefore, the concentration of the total amount of the diamine component and the tetracarboxylic acid component is preferably 1 to 50% by mass, more preferably 5 to 30% by mass in the reaction solution. The initial stage of the reaction is carried out at a high concentration, and then an organic solvent can be added.

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

  The polyamic acid ester can be obtained by reacting the tetracarboxylic acid diester dichloride with the diamine component as described above, or reacting the tetracarboxylic acid diester with the diamine component in the presence of an appropriate condensing agent or base. it can. Alternatively, it can also be obtained by previously synthesizing a polyamic acid by the above method and esterifying the carboxyl group of the polyamic acid using a polymer reaction.

  Specifically, for example, tetracarboxylic acid diester dichloride and a diamine component are present in the presence of a base and an organic solvent at −20 ° C. to 150 ° C., preferably 0 ° C. to 50 ° C., for 30 minutes to 24 hours, preferably 1 By reacting for 4 to 4 hours, a polyamic acid ester can be synthesized.

  As the base, pyridine, triethylamine, and 4-dimethylaminopyridine can be used, but pyridine is preferable because the reaction proceeds gently. The addition amount of the base is preferably 2 to 4 times the molar amount of the tetracarboxylic acid diester dichloride from the viewpoint of easy removal and high molecular weight.

  Further, when polycondensation of a tetracarboxylic acid diester and a diamine component in the presence of a condensing agent, as a base, triphenyl phosphite, dicyclohexylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, N, N′-carbonyldiimidazole, dimethoxy-1,3,5-triazinylmethylmorpholinium, O- (benzotriazol-1-yl) -N, N, N ′, N′-tetramethyluronium Tetrafluoroborate, O- (benzotriazol-1-yl) -N, N, N ′, N′-tetramethyluronium hexafluorophosphate, (2,3-dihydro-2-thioxo-3-benzoxa Zolyl) phosphonic acid diphenyl, 4- (4,6-dimethoxy-1,3,5-triazin-2-yl Etc. can be used 4-methoxy mol ho potassium chloride n- hydrate.

  In the method using the condensing agent, the reaction proceeds efficiently by adding Lewis acid as an additive. As the Lewis acid, lithium halides such as lithium chloride and lithium bromide are preferable. The addition amount of the Lewis acid is preferably 0.1 to 1.0 times the molar amount of the diamine or tetracarboxylic acid diester to be reacted.

  The solvent used in the above reaction can be the same solvent as that used in the synthesis of the polyamic acid shown above. However, N-methyl-2-pyrrolidone, γ -Butyrolactone is preferable, and these may be used alone or in combination. The concentration at the time of synthesis is such that in the reaction solution of a tetracarboxylic acid derivative such as tetracarboxylic acid diester dichloride or tetracarboxylic acid diester and a diamine component, from the viewpoint that polymer precipitation is difficult to occur and a high molecular weight product is easily obtained. The total concentration is preferably 1 to 30% by mass, and more preferably 5 to 20% by mass. Moreover, in order to prevent hydrolysis of tetracarboxylic acid diester dichloride, the solvent used for the synthesis of the polyamic acid ester is preferably dehydrated as much as possible, and it is preferable to prevent mixing of outside air in a nitrogen atmosphere.

  The polyimide precursor thus polymerized is, for example, a polymer having a repeating unit represented by the following formula [a].

（式［ａ］中、Ｒ_１１は、原料のテトラカルボン酸成分に由来する４価の有機基であり、Ｒ_１２は、原料のジアミン成分に由来する２価の有機基であり、Ａ_１１およびＡ_１２は、水素原子または炭素数１〜４のアルキル基であり、それぞれ同じであっても異なってもよく、ｊは正の整数を示す。）

(In the formula [a], R ₁₁ is a tetravalent organic group derived from the raw material tetracarboxylic acid component, R ₁₂ is a divalent organic group derived from the raw material diamine component, and A ₁₁ and A ₁₂ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, which may be the same or different, and j represents a positive integer.)

In the above formula [a], each of R ₁₁ and R ₁₂ may be one type and a polymer having the same repeating unit, or R ₁₁ and R ₁₂ may be a plurality of types and a polymer having a repeating unit having a different structure. But you can.

In the above formula [a], R ₁₁ is a group derived from a tetracarboxylic acid component represented by the following formula [c] or the like which is a raw material. In addition, if R ₁₂ is a group derived from a diamine component represented by the following formula [b] as a raw material, for example, R ₁₂ is a group derived from a diamine compound represented by the above formula (1), C ₆ H ₃ —Y ⁵ —Y ⁴ —OCO—CH═CH—O—Y ¹ —Y ² —Y ³ having two bonds.

（式［ｂ］および式［ｃ］中、Ｒ_１１およびＲ_１２は、式［ａ］で定義したものと同じである。）

(In formula [b] and formula [c], R ₁₁ and R ₁₂ are the same as defined in formula [a].)

  And a polyimide is obtained by carrying out dehydration ring closure of such a polyimide precursor.

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

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

  The catalyst imidation of the polyimide precursor 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 of the amido acid group. Is double. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, pyridine is preferable because it has a basicity appropriate for advancing the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. Among them, use of acetic anhydride is preferable because purification after completion of the reaction is facilitated. The imidization rate by catalytic imidation can be controlled by adjusting the amount of catalyst, reaction temperature, and reaction time.

  In addition, what is necessary is just to throw a reaction solution into a solvent and to precipitate, when collect | recovering the produced | generated polyimide precursors and a polyimide from polyimide precursors, such as polyamic acid and polyamic acid ester, and the reaction solution of a polyimide. Examples of the solvent used for precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. The polyimide precursor or polyimide that has been deposited in a solvent and collected can be collected by filtration, and then dried at normal temperature or under reduced pressure at room temperature or by heating. Moreover, the polyimide precursor and polyimide which collect | recovered and collect | recovered are redissolved in an organic solvent, and the operation which carries out reprecipitation collection | recovery is repeated 2 to 10 times, The impurity in a polyimide precursor or a polyimide can be decreased. Examples of the solvent at this time include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more kinds of solvents selected from these because purification efficiency is further increased.

  The dehydration cyclization rate (imidation rate) of the amic acid group of the polyimide does not necessarily need to be 100%, and can be arbitrarily selected in the range of 0% to 100% depending on the application and purpose. % Is preferred.

  Polyamide can also be synthesized in the same manner as the polyamic acid ester.

  The molecular weight of the polyimide precursor, polyimide, or polyamide of the present invention is determined by GPC (Gel) in consideration of the strength of the obtained polymer film (liquid crystal alignment film), workability at the time of forming the polymer film, and uniformity of the polymer film. The weight average molecular weight measured by Permeation Chromatography) is preferably 5,000 to 1,000,000, and more preferably 10,000 to 150,000.

  The liquid crystal aligning agent of this invention contains polyimide precursors, such as the polyamic acid of this invention which has the structure represented by the said Formula [I], and a polyamic acid ester, polyamic acid ester, a polyimide, and polyamide. A liquid crystal aligning agent is a solution for forming a liquid crystal aligning film, and is a solution in which a polymer component for forming a liquid crystal aligning film is dispersed or dissolved in an organic solvent. The liquid crystal alignment film is a film for aligning liquid crystals in a predetermined direction. In the present invention, the polymer component contains at least one selected from the polyimide precursor, polyimide and polyamide of the present invention.

  In the liquid crystal aligning agent of the present invention, all of the polymer components contained may be the polyimide precursor, polyimide or polyamide of the present invention. In addition, the polyimide precursor, polyimide or polyamide of the present invention, These polymers may be mixed. When another polymer is contained as the polymer component, the content of the other polymer in the total amount of the polymer component is 0.5% by mass to 80% by mass, preferably 40% by mass to 80% by mass.

  Examples of such other polymers include diamine components that are reacted with a tetracarboxylic dianhydride component, dicarboxylic acid, or the like, other than a diamine having a structure represented by the above formula [I] of the present invention as a side chain. And polyimide precursors obtained by using only diamines, polyimides and polyamides. Furthermore, a polyimide precursor, a polymer other than polyimide or polyamide, specifically, an acrylic polymer, a methacrylic polymer, polysiloxane, polystyrene, or the like can be given.

  In the liquid crystal aligning agent of the present invention, the content ratio of at least one selected from the polyimide precursor of the present invention, polyimide and polyamide, and other polymers to be mixed as necessary is 1% by mass with respect to the total amount of the polymer components. -20 mass% is preferable, More preferably, it is 3 mass%-15 mass%, Most preferably, it is 3-10 mass%.

  The solvent which the liquid crystal aligning agent of this invention contains will not be specifically limited if it is an organic solvent which can melt | dissolve polymer components, such as the polyimide precursor of this invention, a polyimide, and polyamide. Specific examples thereof include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethylpyrrolidone, N-vinylpyrrolidone, dimethyl sulfoxide, tetra Methylurea, pyridine, dimethylsulfone, hexamethylsulfoxide, γ-butyrolactone, 3-methoxy-N, N-dimethylpropanamide, 3-ethoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropane Amide, 1,3-dimethyl-imidazolidinone, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, cyclohexanone, ethylene carbonate, propylene carbonate, diglyme, - such as hydroxy-4-methyl-2-pentanone and the like. These may be used alone or in combination.

  As long as the liquid crystal aligning agent of the present invention does not impair the effects of the present invention, an organic solvent (also called a poor solvent) that improves the uniformity and surface smoothness of the polymer film when the liquid crystal aligning agent is applied, or A compound may be contained. Furthermore, you may contain the compound etc. which improve the adhesiveness of a liquid crystal aligning film and a board | substrate.

  Specific examples of poor solvents that improve film thickness uniformity and surface smoothness include isopropyl alcohol, methoxymethylpentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol Tolu, ethyl carbitol acetate, 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, methylcyclo Hexene, propyl ether, dihexyl ether, n-to Sun, 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, 3-methoxypropionic acid Methyl, methyl ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 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-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol, lactate methyl ester, lactate ethyl ester, lactate n-propyl ester, lactate n-butyl ester or lactic acid Examples thereof include organic solvents having a low surface tension such as isoamyl ester.

  These poor solvents may be used alone or in combination. When using the above solvent, it is preferable that it is 5-80 mass% of the whole solvent contained in a liquid crystal aligning agent, More preferably, it is 20-60 mass%.

  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) and the like. 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 polymer component contained in the liquid crystal aligning agent. .

  Examples of the compound that improves the adhesion between the liquid crystal alignment film and the substrate include a functional silane-containing compound and an epoxy group-containing compound, such as 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-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-To Methoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether Polyethylene glycol Rudiglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromo Neopentyl 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.

  When using the compound which improves adhesiveness with a board | substrate, it is preferable that the usage-amount is 0.1-30 mass parts with respect to 100 mass parts of polymer components contained in a liquid crystal aligning agent, More preferably. Is 1-20 parts by mass. If the amount used is less than 0.1 parts 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 aligning agent of the present invention has a dielectric or conductive material for the purpose of changing the electrical properties such as the dielectric constant and conductivity of the liquid crystal aligning film, as long as the effects of the present invention are not impaired. Further, a crosslinkable compound for the purpose of increasing the hardness and density of the liquid crystal alignment film may be added.

  The liquid crystal aligning agent of this invention can be used as a liquid crystal aligning film by apply | coating and baking on a board | substrate and performing alignment processing by light irradiation. Such a liquid crystal alignment film of the present invention contains a polyimide precursor having a structure represented by the above formula [I] as a side chain, polyimide or polyamide, so that the liquid crystal alignment performance is hardly deteriorated by a backlight. The liquid crystal alignment performance by AC driving is hardly deteriorated. In addition, the liquid crystal aligning agent of this invention can be used also for uses other than the liquid crystal aligning film (photo-alignment film) formed by the alignment process by light irradiation mentioned above. Specifically, after baking, it can be used as a liquid crystal alignment film formed by rubbing for vertical alignment or the like or without alignment.

  The substrate is not particularly limited as long as it is a highly transparent substrate. In addition to a glass substrate, a plastic substrate such as an acrylic substrate or a polycarbonate substrate can also be used. From the viewpoint of simplifying the process, it is preferable to use a substrate on which an ITO (Indium Tin Oxide) electrode for driving a liquid crystal is formed. In the reflective liquid crystal display element, an opaque substrate such as a silicon wafer can be used if only one substrate is used, and a material that reflects light such as aluminum can be used as an electrode in this case. As a high-performance element such as a TFT type element, an element in which an element such as a transistor is formed between an electrode for driving a liquid crystal and a substrate is used.

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

  After the liquid crystal aligning agent is applied on the substrate, the liquid crystal alignment is performed by evaporating the solvent at 50 to 300 ° C., preferably 80 to 250 ° C., by a heating means such as a hot plate, a thermal circulation oven or an IR (infrared) oven. A film (polymer film) can be formed. If the thickness of the liquid crystal alignment film after baking is too thick, it is disadvantageous in terms of power consumption of the liquid crystal display element, and if it is too thin, the reliability of the liquid crystal display element may be lowered. Is 10 to 100 nm. When the liquid crystal is vertically aligned, horizontally aligned, or tilted, the liquid crystal alignment film after baking may be irradiated with radiation such as polarized ultraviolet rays or rubbed.

  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 aligning agent of the present invention by the method described above, and then preparing a liquid crystal cell by a known method. For example, the two substrates disposed so as to face each other, the liquid crystal layer provided between the substrates, and the liquid crystal aligning agent of the present invention provided between the substrate and the liquid crystal layer. A liquid crystal display device comprising a liquid crystal cell having a liquid crystal alignment film. As such a liquid crystal display element of the present invention, a vertical alignment (VA) method, a twisted nematic (TN) method, a horizontal alignment (IPS) method, an OCB alignment (OCB: OCB). There are various types such as Optically Compensated Bend). Note that the liquid crystal alignment film only needs to be provided on at least one of the two substrates.

  The substrate used in the liquid crystal display element of the present invention is not particularly limited as long as it is a highly transparent substrate, but is usually a substrate on which a transparent electrode for driving liquid crystal is formed. As a specific example, the thing similar to the board | substrate described with the said liquid crystal aligning film can be mentioned.

  In addition, the liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention on this substrate and then firing, and irradiating with radiation such as polarized ultraviolet rays as necessary. It is.

  The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited, and a positive liquid crystal having positive dielectric anisotropy or a negative liquid crystal having negative dielectric anisotropy can be used. As a specific example, a liquid crystal material used in a conventional vertical alignment method, for example, MLC-6608, MLC-6609 manufactured by Merck & Co., Inc. can be used.

  For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, spacers such as beads are dispersed on the liquid crystal alignment film of one substrate, and the liquid crystal alignment film surface is on the inside. In this way, the other substrate is bonded and the liquid crystal is injected under reduced pressure to seal, or the liquid crystal is dropped on the liquid crystal alignment film surface on which the spacers are dispersed and then the substrate is bonded and sealed. Can be illustrated. The thickness of the spacer at this time is preferably 1 to 30 μm, more preferably 2 to 10 μm.

  As described above, the liquid crystal display device produced using the liquid crystal aligning agent of the present invention has a liquid crystal alignment film in which deterioration of liquid crystal alignment performance due to backlight irradiation is suppressed, and thus has excellent long-term display characteristics. It will be. In addition, since it has a liquid crystal alignment film in which deterioration of the liquid crystal alignment performance is suppressed even when driven by applying AC for a long period of time, it becomes a liquid crystal display element in which image sticking hardly occurs even when driven by AC for a long period of time.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to the examples.

The abbreviations used in this example are as follows.
(Tetracarboxylic dianhydride)
CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride

(Diamine)
DA-1: (E) -3,5-diaminobenzoyl 3- (4- (trans-4-heptylcyclohexyl) phenoxy) acrylate represented by the following formula
DA-2: (E) -3,5-diaminobenzoyl 3- (4- (trans-4′-pentyl- [1,1′-bi (cycloclohexan)]-4-yl) phenoxy) represented by the following formula: acrylate
PCH: 1,3-diamino-4- [4- (4-heptylcyclohexyl) phenoxy] benzene

(Organic solvent)
NMP: N-methyl-2-pyrrolidone BCS: Butyl cellosolve

<Polymer molecular weight measurement>
The molecular weight of the polymer (polyamic acid or the like) was measured as follows using a room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Senshu Scientific Co., Ltd. and a column (KD-803, KD-805) manufactured by Shodex. .
Column temperature: 50 ° C
Eluent: N, N′-dimethylformamide (as additives, lithium bromide-hydrate (LiBr · H ₂ O) is 30 mmol / L, phosphoric acid / anhydrous crystal (o-phosphoric acid) is 30 mmol / L, Tetrahydrofuran (THF) 10ml / L)
Flow rate: 1.0 ml / min Standard sample for preparing 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).

  Synthesis Example 1 Synthesis of DA-1 ((E) -3,5-diaminobenzyl 3- (4- (trans-4-heptylcyclohexyl) phenoxy) acrylate)

（上記反応式中、シクロヘキシレンのシス−トランス異性は、それぞれトランス異性体である。）

(In the above reaction formula, cis-trans isomerism of cyclohexylene is a trans isomer.)

  Compound [A] (11.00 g, 55.5 mmol), triphenylphosphine (16.02 g, 61.1 mmol), tetrahydrofuran (80 g) (hereinafter also referred to as THF) was added to a 1 L four-necked flask, and the atmosphere was replaced with nitrogen. After that, the reaction solution was cooled to 0 ° C. A mixed solution of propiolic acid [B] (4.67 g, 66.6 mmol), isopropyl azodicarboxylate (12.34 g, 61.1 mmol), and THF (120 g) was gradually added dropwise thereto. After completion of the dropping, the reaction solution was returned to 23 ° C. and further stirred. The reaction was traced by high performance liquid chromatography (HPLC). After confirming the completion of the reaction, the solvent was distilled off by an evaporator to obtain a crude product of compound [C].

Next, the compound [D] (15.23 g, 55.5 mmol) and THF (140 g) are added to the compound [C] obtained above, and 1,4-diazabicyclo [2.2.2] octane (hereinafter, referred to as “the compound [D]”). (Also expressed as DABCO) (622 mg, 5.55 mmol) was added, and the mixture was stirred at 23 ° C. The reaction was monitored by HPLC, and after confirming the completion of the reaction, 200 g of a 10 wt% aqueous sodium hydroxide solution was added, and the mixture was extracted with a mixed solution of ethyl acetate (200 mL) / hexane (600 mL). After removing the aqueous layer, the extract was washed 3 times with saturated brine (500 g), dried over magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a crude product of compound [E]. Thereafter, 2-propanol (hereinafter also referred to as IPA) (200 g) was added to the obtained crude product [E] and stirred for 30 minutes, then allowed to cool to 30 ° C., filtered and dried under reduced pressure. Compound [E] was obtained (15.4 g, 53% yield). The result of having measured the obtained compound [E] by NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 9.01 (1H, t), 8.57-8.56 (2H, m), 7.88 (1H, d), 7.23-7.01 (2H, m), 7.01-6.98 (2H , m), 5.58 (1H, d), 5.35 (2H, s), 2.53-2.44 (1H, m), 1.88-1.85 (4H, m), 1.49-1.00 (17 m), 0.89 (3H, t) .

Compound [E] (14.81 g, 28.2 mmol), iron (9.46 g, 169 mmol), 10 wt% aqueous ammonium chloride (45 g), and ethyl acetate (130 g) were added to a 500 mL four-necked flask at 70 ° C. Heating and stirring were performed. The reaction was monitored by HPLC, and after confirming the completion of the reaction, the solid content was removed by Celite filtration and washed with ethyl acetate and distilled water. After analyzing the filtrate and removing the aqueous layer, the organic layer was washed three times with distilled water (500 g) and dried over magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a crude compound DA-1. Got. Methanol (30 g) was added to the crude product and stirred at room temperature for 30 minutes, followed by filtration, washing with methanol and drying under reduced pressure to obtain Compound DA-1 (9.9 g, yield 76%). The results of NMR measurement of the obtained compound DA-1 are shown below.
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.81 (1H, d), 7.20-7.18 (2H, m), 6.98-6.96 (2H, m), 6.11 (2H, d), 5.98 (1H, t ), 5.54 (1H, m), 4.99 (2H, s), 3.60 (4H, brs), 2.48-2.42 (1H, m), 1.87-1.85 (4H, m), 1.42-1.20 (14H, m), 1.08-0.99 (3H, m), 0.89-0.87 (3H, m).

  Synthesis Example 2 DA-2 ((E) -3,5-diaminobenzyl 3- (4- (trans-4'-pentyl- [1,1'-bi (cyclohexan)]-4-yl) phenoxy) acrylate ) Synthesis

（上記反応式中、シクロヘキシレンのシス−トランス異性は、それぞれトランス異性体である。）

(In the above reaction formula, cis-trans isomerism of cyclohexylene is a trans isomer.)

Propiolic acid [B] (3.23 g, 46.2 mmol) and N, N′-dimethylformamide (40 g) (hereinafter referred to as DMF) were added to a 200 mL four-necked flask, and the mixture was stirred at 23 ° C. Sodium hydrogen carbonate (7.76 g, 92.4 mmol) was added little by little as a powder, and the mixture was stirred at room temperature for 30 minutes. Thereafter, the solution was heated to 50 ° C., and a solution of 3,5-dinitrobenzyl chloride [F] (10.00 g, 46.2 mmol) in DMF (60 g) was gradually added dropwise. Reaction tracking was performed by HPLC. After completion of the reaction, ethyl acetate (600 g), hexane (200 g), and distilled water (600 g) were added, and a liquid separation operation was performed to remove the aqueous layer. The organic layer was washed 3 times with distilled water (500 g) and dried over magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain compound [C] (11.05 g, yield 96%). The result of having measured the obtained compound [C] by NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 9.06-9.05 (1H, m), 8.60-8.59 (2H, m), 5.41 (2H, s), 3.04 (1H, s).

In a 200 mL four-necked flask, compound [C] (11.05 g, 44.2 mmol), compound [G] (14.51 g, 44.2 mmol), 1,4-diazabicyclo [2.2.2] octane (495 mg). 4.42 mmol) and tetrahydrofuran (140 g) were added, and the mixture was stirred at 23 ° C. The reaction was traced by HPLC. After completion of the reaction, 10 wt% aqueous sodium hydroxide solution (100 g) was added, ethyl acetate (200 g) was further added, and the aqueous layer was removed by a liquid separation operation. The organic layer was washed with saturated brine (500 g) three times and dried over magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a crude product of compound [H]. 2-Propanol (180 g) was added to this crude product, and the mixture was heated to reflux with stirring for 30 minutes, then cooled to 40 ° C., filtered and washed with IPA, and then dried under reduced pressure to obtain compound [H]. (25.3 g, 98% yield). The result of having measured the obtained compound [H] by NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 9.00 (1H, t), 8.57-8.56 (2H, m), 7.88 (1H, d), 7.22-7.21 (2H, m), 7.00-6.98 (2H , m), 5.58 (1H, d), 5.36 (2H, s), 2.50-2.37 (1H, m), 1.94-0.84 (30H, m).

Compound [H] (25.3 g, 44.2 mmol), iron (14.80 g, 265 mmol), 10 wt% ammonium chloride aqueous solution (71 g), and ethyl acetate (230 g) were added to a 500 mL four-necked flask at 70 ° C. Heating and stirring were performed. The reaction was monitored by HPLC, and after confirming the completion of the reaction, the solid content was removed by Celite filtration and washed with ethyl acetate and distilled water. After analyzing the filtrate and removing the aqueous layer, the organic layer was washed 3 times with distilled water (500 g) and dried over magnesium sulfate, and then the solvent was distilled off with an evaporator to obtain a crude product of compound DA-2. Got. Methanol (50 g) was added to the crude product and stirred at room temperature for 30 minutes, followed by filtration, washing with methanol and drying under reduced pressure to obtain Compound DA-2 (14.7 g, yield 64%). The results of NMR measurement of the obtained compound DA-2 are shown below.
¹ H-NMR (400 MHz, CDCl ₃ , δ ppm): 7.81 (1H, d), 7.20-7.18 (2H, m), 6.98-6.96 (2H, m), 6.11 (2H, d), 5.98 (1H, t ), 5.54 (1H, m), 4.99 (2H, s), 3.59 (4H, brs), 2.53-2.38 (1H, m), 1.87-0.90 (30H, m).

<Synthesis Example 3> Synthesis of DA-3 According to Synthesis Example 1-1 of Patent Document 1, DA-3 was synthesized.

<Synthesis Example 4> Synthesis of DA-4 DA-4 was synthesized according to Example 1 of JP-T-2001-517719.

<Creation of liquid crystal aligning agent A1>
CBDA (0.288 g, 1.50 mmol) and DA-1 (0.697 g, 1.5 mmol) were mixed in NMP (5.58 g) and reacted at room temperature for 10 hours to obtain a polyamic acid solution. To this polyamic acid solution, BCS (4.93 g) and NMP (4.93 g) were added to dilute the polyamic acid concentration to 6% by mass, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent A1. This polyamic acid had a number average molecular weight of 14,000 and a weight average molecular weight of 74,000.

<Creation of liquid crystal aligning agent A2>
CBDA (0.485 g, 2.50 mmol) and DA-2 (1.297 g, 2.5 mmol) were mixed in NMP (10.1 g) and reacted at room temperature for 10 hours to obtain a polyamic acid solution. To this polyamic acid solution, BCS (8.91 g) and NMP (8.91 g) were added to dilute the polyamic acid concentration to 6% by mass, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent A2. The number average molecular weight of this polyamic acid was 3500, and the weight average molecular weight was 5300.

<Creation of liquid crystal aligning agent A3>
CBDA (0.485 g, 2.50 mmol) and DA-3 (1.052 g, 2.5 mmol) were mixed in NMP (8.71 g) and reacted at room temperature for 10 hours to obtain a polyamic acid solution. To this polyamic acid solution, BCS (7.68 g) and NMP (7.68 g) were added to dilute the polyamic acid concentration to 6% by mass, and the mixture was stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent A3. The number average molecular weight of this polyamic acid was 5500, and the weight average molecular weight was 13000.

<Synthesis of Liquid Crystal Alignment Agent A4>
CBDA (1.537 g, 7.8 mmol), DA-4 (2.832 g, 6.4 mmol), PCH (0.609 g, 1.6 mmol) were mixed in NMP (19.91 g) and at room temperature for 10 hours. A polyamic acid solution was obtained by reaction. To this polyamic acid solution, NMP (33.19 g) and BCS (24.89 g) were added to dilute the polyamic acid concentration to 6% by mass, and the mixture was stirred at room temperature for 5 hours to obtain liquid crystal aligning agent A4. The number average molecular weight of this polyamic acid was 12,000, and the weight average molecular weight was 24,000.

<Example 1>
Using liquid crystal aligning agent A1, the liquid crystal aligning film was produced in the procedure shown below, and UV (ultraviolet) absorption spectrum was measured. In addition, a liquid crystal cell was prepared using the liquid crystal aligning agent A1 according to the procedure described below, and evaluation of a pretilt angle, evaluation of AC (alternating current) image sticking, and evaluation of backlight resistance were performed.

[Measurement of UV absorption spectrum]
Liquid crystal aligning agent A1 was spin-coated on a quartz substrate, dried for 90 seconds on a hot plate at 80 ° C., and then baked for 30 minutes in a hot air circulation oven at 200 ° C. to form a liquid crystal alignment film having a thickness of 100 nm. The substrate on which the liquid crystal alignment film was formed was measured for UV absorption spectrum using UV-3600 manufactured by Shimadzu Corporation, and the maximum absorption wavelength (λ _max ) was determined. The results are shown in Table 1.

[Production of liquid crystal cell]
The liquid crystal aligning agent A1 is spin-coated on the surface of the glass substrate with a transparent electrode made of ITO film on which the ITO film is formed, dried on an 80 ° C. hot plate for 90 seconds, and then heated in a 200 ° C. hot air circulation oven for 30 minutes. Baking was performed to form a liquid crystal alignment film having a thickness of 100 nm. The substrate on which the liquid crystal alignment film was formed was irradiated with 254 nm linearly polarized light UV having an irradiation intensity of 2.0 mW / cm ⁻² with an exposure amount of 0 to 1000 mJ. The direction of the incident light was inclined by 40 ° with respect to the normal direction of the substrate. The linearly polarized light UV was prepared by passing a 254 nm polarizing plate through a 254 nm bandpass filter through the ultraviolet light of a high-pressure mercury lamp.

  Two substrates were prepared, and 4 μm bead spacers were dispersed on the liquid crystal alignment film of one substrate, and then a sealant (XN-1500T manufactured by Kyoritsu Chemical Co., Ltd.) was printed thereon. Next, the liquid crystal alignment film surfaces of the two substrates are made to face each other, pressure-bonded so that the projection direction of the optical axis of the linearly polarized light UV on each substrate is antiparallel, and the sealant is thermally cured at 150 ° C. for 105 minutes. I let you. A negative liquid crystal (MLC-6608, manufactured by Merck & Co., Inc.) was injected into the empty cell by a reduced pressure injection method, and an isotropic treatment (liquid crystal realignment treatment by heating) was performed in an oven at 120 ° C. to produce a liquid crystal cell.

[Evaluation of pretilt angle]
The pretilt angle of the liquid crystal cell was measured by the Mueller matrix method using an “Axo Scan” manufactured by Axo Metrix. The results are shown in Table 1.

[Evaluation of AC image sticking]
After preparing the liquid crystal cell, the liquid crystal cell whose pretilt angle was measured was driven at an AC voltage of 16 Vpp for 240 hours, and after the drive was stopped, the pretilt angle of the liquid crystal cell was measured again one hour after the drive was stopped. Changes were evaluated. When the change in pretilt angle before and after AC driving (ACΔangle = pretilt angle before AC driving−pretilt angle after AC driving) was less than 0.2 °, it was determined that the AC image sticking characteristics were good. ACΔangle is shown in Table 1.

[Evaluation of backlight resistance]
After preparing the liquid crystal cell, the liquid crystal cell whose pretilt angle was measured was left (aging) on a backlight (BL) for 40 inch type liquid crystal TV (wavelength 400 to 800 nm), then removed from the BL, and 1 hour later. The pretilt angle of the liquid crystal cell was measured again, and the change in the pretilt angle before and after aging was evaluated. When the change in pretilt angle before and after aging (BLΔangle = pretilt angle before BL irradiation−pretilt angle after BL irradiation) was less than 0.1 °, the BL resistance was judged to be good. BLΔangle is shown in Table 1.

<Example 2>
A liquid crystal alignment film was prepared in the same manner as in Example 1 except that the liquid crystal alignment agent A2 was used instead of the liquid crystal alignment agent A1, and the UV absorption spectrum of the obtained liquid crystal alignment film was measured.

  Further, a liquid crystal cell was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent A2 was used instead of the liquid crystal aligning agent A1, and the obtained liquid crystal cell was evaluated for pretilt angle, evaluation for AC image sticking, and backlight. Resistance was evaluated. The results are shown in Table 1.

<Comparative Example 1>
A liquid crystal alignment film was prepared in the same manner as in Example 1 except that the liquid crystal alignment agent A3 was used instead of the liquid crystal alignment agent A1, and the UV absorption spectrum of the obtained liquid crystal alignment film was measured.

  A liquid crystal cell was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent A3 was used instead of the liquid crystal aligning agent A1, and the irradiation wavelength of the linearly polarized light UV was changed to 313 nm. The evaluation of the pretilt angle, the evaluation of AC image sticking, and the evaluation of backlight resistance were performed. The results are shown in Table 1.

<Comparative example 2>
A liquid crystal alignment film was prepared in the same manner as in Example 1 except that the liquid crystal alignment agent A4 was used instead of the liquid crystal alignment agent A1, and the UV absorption spectrum of the obtained liquid crystal alignment film was measured.

  Further, a liquid crystal cell was produced in the same manner as in Example 1 except that the liquid crystal aligning agent A4 was used instead of the liquid crystal aligning agent A1, and the irradiation wavelength of the linearly polarized light UV was changed to 313 nm. The evaluation of the pretilt angle, the evaluation of AC image sticking, and the evaluation of backlight resistance were performed. The results are shown in Table 1.

  From the results of Table 1 above, the liquid crystal display elements of Example 1 and Example 2 using the polymer having the structure represented by the formula [I] of the present invention in the side chain have a high pretilt angle, that is, high verticality. It was confirmed that the pre-tilt angle was little changed before and after AC driving because of the orientation ability, and good AC image sticking characteristics were exhibited. Moreover, because the structure represented by the formula [I] of the present invention has a UV absorption band in the vicinity of 254 nm which is a low wavelength region, the liquid crystal display elements of Example 1 and Example 2 are affected by the backlight. It was confirmed that the pretilt angle hardly changed even when exposed to backlight for a long time. On the other hand, Comparative Example 1 and Comparative Example 2 using the conventional diamine having a cinnamoyl group are likely to be affected by the backlight because of absorption near 300 nm, and gradually increase the pretilt angle when exposed to the backlight for a long time. It was found to cause changes.

Claims (6)

Polyimide precursor having a structure represented by the following formula [I] as a side chain, a polymer, wherein the polyimide precursor is a polyimide obtained by imidizing.

Wherein Y ¹ is a monocyclic ring having 5 or 6 atoms, two adjacent monocyclic rings having 5 or 6 atoms, a bicyclic ring system having 8 to 10 atoms, or An unsubstituted or substituted carbocyclic or heterocyclic divalent aromatic group selected from 13 or 14 tricyclic ring systems, wherein Y ² is a single bond or an ether A divalent linking group selected from the group consisting of a bond, an ester bond, an amide bond and a urethane bond, and Y ³ is a straight chain of 3 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom It is a monovalent organic group having an alkyl group or an alicyclic skeleton having 4 to 40 carbon atoms.) The polymer according to claim 1, wherein the polymer is obtained using a diamine represented by the following formula (1).

Wherein Y ¹ is a monocyclic ring having 5 or 6 atoms, two adjacent monocyclic rings having 5 or 6 atoms, a bicyclic ring system having 8 to 10 atoms, or An unsubstituted or substituted carbocyclic or heterocyclic divalent aromatic group selected from 13 or 14 tricyclic ring systems, wherein Y ² is a single bond or an ether A divalent linking group selected from the group consisting of a bond, an ester bond, an amide bond and a urethane bond, and Y ³ is a straight chain of 3 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom An alkyl group or a monovalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms, Y ⁴ is a single bond, a methylene group or an alkylene group having 2 to 6 carbon atoms, Y ⁵ is a single bond, Oxygen atom, * —OCO— or —CH ₂ O— * (however, the bond with “*” is Y ⁴ is a single bond.) However, when Y ⁴ is a single bond, Y ⁵ is a single bond.   A liquid crystal aligning agent comprising the polymer according to claim 1.   A liquid crystal alignment film obtained using the liquid crystal aligning agent according to claim 3.   A liquid crystal display element comprising the liquid crystal alignment film according to claim 4. A diamine represented by the following formula (1):

Wherein Y ¹ is a monocyclic ring having 5 or 6 atoms, two adjacent monocyclic rings having 5 or 6 atoms, a bicyclic ring system having 8 to 10 atoms, or An unsubstituted or substituted carbocyclic or heterocyclic divalent aromatic group selected from 13 or 14 tricyclic ring systems, wherein Y ² is a single bond or an ether A divalent linking group selected from the group consisting of a bond, an ester bond, an amide bond and a urethane bond, and Y ³ is a straight chain of 3 to 20 carbon atoms in which a hydrogen atom may be substituted with a fluorine atom An alkyl group or a monovalent organic group having an alicyclic skeleton having 4 to 40 carbon atoms, Y ⁴ is a single bond, a methylene group or an alkylene group having 2 to 6 carbon atoms, Y ⁵ is a single bond, Oxygen atom, * —OCO— or —CH ₂ O— * (however, the bond with “*” is Y ⁴ is a single bond.) However, when Y ⁴ is a single bond, Y ⁵ is a single bond.