JPWO2014092170A1 - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

A liquid crystal containing at least one polymer selected from a polyimide precursor and a polyimide obtained by polymerizing a tetracarboxylic acid component and a diamine component, and comprising the following component (A) and component (B): Alignment agent. (A) component: The tetracarboxylic acid component contains at least one selected from 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, and the diamine component A polymer containing a diamine having a side chain represented by the following formula (1) [Chemical Formula 1] (In formula (1), P1 represents a single bond, etc., and Q1, Q2, and Q3 are each independently a divalent group. Represents a benzene ring or the like, p, q and r each independently represent an integer of 0 or 1, and P2 represents a hydrogen atom or the like.) (B) component: the tetracarboxylic acid component, and a diamine component Is a polymer composed only of a diamine having a —CR212— group in the main chain (wherein two R21 each independently represents a hydrogen atom or the like).

Description

  The present invention relates to a liquid crystal aligning agent used for producing a liquid crystal alignment film, a liquid crystal alignment film using the same, and a liquid crystal display element.

  Liquid crystal display elements are currently widely used as display devices. A liquid crystal alignment film, which is a constituent member of a liquid crystal display element, is a film for uniformly arranging liquid crystals. However, not only the alignment uniformity of liquid crystals but also various characteristics are required.

  For example, in the manufacturing process of the liquid crystal alignment film, an alignment process called rubbing is generally performed by rubbing the surface of the polymer film with a cloth. However, if the rubbing resistance of the liquid crystal alignment film is insufficient, the film is scraped to generate scratches and dust, or the film itself is peeled off, thereby degrading the display quality of the liquid crystal display element. The liquid crystal display element is driven by applying a voltage to the liquid crystal. For this reason, when the voltage holding ratio (VHR) of the liquid crystal alignment film is low, a sufficient voltage is not applied to the liquid crystal, and the display contrast is lowered. In addition, when charge is accumulated in the liquid crystal alignment film due to the voltage for driving the liquid crystal and it takes time for the accumulated charge to be removed, a phenomenon such as afterimage or display burn-in occurs.

  Various proposals have been made for simultaneously satisfying some of the above required characteristics. For example, Patent Document 1 proposes a method for obtaining a liquid crystal alignment film having excellent rubbing resistance and less afterimage and image sticking. Further, Patent Document 2 proposes a method for obtaining a liquid crystal alignment film having excellent liquid crystal alignment properties, alignment regulating power, and rubbing resistance, a high voltage holding ratio, and reduced charge accumulation.

International Publication No. WO02 / 33481 Pamphlet International Publication No. WO2004 / 053583 Pamphlet

  In recent years, high-definition images such as photographs and moving pictures are displayed on multifunctional mobile phones (smartphones) and tablet terminals, such as TVs and personal computers. High-quality display performance equivalent to or better than that has been demanded.

  By the way, display screens for mobile phones and tablet terminals are frequently turned on and off (or the backlight is frequently turned on and off), and are watched by users from the moment they are displayed. There are features that are not often seen in other applications. For this reason, the requirements for charge accumulation and the like are more severe than ever.

  An object of the present invention is to solve the above-mentioned problems of the prior art, and a liquid crystal capable of obtaining a liquid crystal alignment film having a high voltage holding ratio and a very small charge accumulation while maintaining rubbing resistance. An object is to provide an alignment agent, a liquid crystal alignment film, and a liquid crystal display element.

The inventor has conducted research to achieve the above object, and has arrived at the present invention having the following summary.
1. The liquid crystal aligning agent characterized by containing the following (A) component and the following (B) component.

(A) component: at least one polymer selected from a polyimide precursor obtained by polymerizing a tetracarboxylic acid component and a diamine component and a polyimide obtained by imidizing this polyimide precursor, The tetracarboxylic acid component is 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1- It contains at least one selected from naphthalene succinic acid diester and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid diester dichloride, and the diamine component is represented by the following formula (1): Polymer comprising a diamine having a side chain represented

（式（１）中、Ｐ^１は単結合または２価の有機基を表し、Ｑ^１、Ｑ^２、Ｑ^３はそれぞれ独立して２価のベンゼン環又はシクロヘキサン環を表し、ｐ、ｑ、ｒはそれぞれ独立して０又は１の整数を表し、Ｐ^２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２価の有機基を表す。）
（Ｂ）成分：テトラカルボン酸成分とジアミン成分とを重合反応させることにより得られるポリイミド前駆体及びこのポリイミド前駆体をイミド化して得られるポリイミドから選択される少なくとも一種の重合体であって、前記テトラカルボン酸成分が３，４−ジカルボキシ−１，２，３，４−テトラヒドロ−１−ナフタレンコハク酸二無水物、３，４−ジカルボキシ−１，２，３，４−テトラヒドロ−１−ナフタレンコハク酸ジエステル及び３，４−ジカルボキシ−１，２，３，４−テトラヒドロ−１−ナフタレンコハク酸ジエステルジクロリドから選択される少なくとも一種を含み、なおかつ、前記ジアミン成分が主鎖に−ＣＲ^２１ _２−基（ここで、２つのＲ^２１は、それぞれ独立に水素原子または有機基を表し、２つのＲ^２１が一緒になることで環状構造を形成してもよい。）を有するジアミンのみからなる重合体

(In Formula (1), P ¹ represents a single bond or a divalent organic group, Q ¹ , Q ² , and Q ³ each independently represent a divalent benzene ring or a cyclohexane ring, and p, q, r Each independently represents an integer of 0 or 1, and P ² represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or a divalent organic group having 12 to 25 carbon atoms having a steroid skeleton.)
(B) component: at least one polymer selected from a polyimide precursor obtained by polymerizing a tetracarboxylic acid component and a diamine component and a polyimide obtained by imidizing this polyimide precursor, The tetracarboxylic acid component is 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1- It contains at least one selected from naphthalene succinic acid diester and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid diester dichloride, and the diamine component is -CR ^{21 in the} main chain. ₂ - group (wherein two ^{R 21} each independently represent a hydrogen atom or an organic group, two ^{R 21} are one May form a cyclic structure consisting thing.) Consisting only of a diamine having a polymer

  2. In the component (B), the diamine component consists only of a diamine represented by the following formula (2). The liquid crystal aligning agent of description.

（式（２）中、２つのＸはそれぞれ独立に酸素原子または単結合を表し、ｎは１〜１０の整数を表し、２つのＲ^２２はそれぞれ独立に水素原子、炭素数１〜５のアルキル基、炭素数１〜５のフルオロアルキル基またはフッ素原子を表すか、２つのＲ^２２が一緒になって、炭素数２〜７のアルキレン基を形成することで、環状構造を形成してもよい。）

(In formula (2), two X's each independently represent an oxygen atom or a single bond, n represents an integer of 1 to 10, and two R ^22's each independently represent a hydrogen atom or an alkyl having 1 to 5 carbon atoms. Represents a group, a fluoroalkyl group having 1 to 5 carbon atoms or a fluorine atom, or two R ²² together form an alkylene group having 2 to 7 carbon atoms to form a cyclic structure .)

3. In the component (A), the diamine having a side chain represented by the formula (1) is a diamine represented by the following formula (3). Or 2. Liquid crystal aligning agent as described in.

（式（３）中、Ｐ^１は単結合または２価の有機基を表し、Ｑ^１、Ｑ^２、Ｑ^３はそれぞれ独立して２価のベンゼン環又はシクロヘキサン環を表し、ｐ、ｑ、ｒはそれぞれ独立して０又は１の整数を表し、Ｐ^２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２価の有機基を表す。）

(In Formula (3), P ¹ represents a single bond or a divalent organic group, Q ¹ , Q ² , and Q ³ each independently represent a divalent benzene ring or a cyclohexane ring, and p, q, r Each independently represents an integer of 0 or 1, and P ² represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or a divalent organic group having 12 to 25 carbon atoms having a steroid skeleton.)

  4). 1. ~ 3. A liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to any one of the above to a substrate and baking it.

  5. 4). A liquid crystal display element comprising the liquid crystal alignment film described in 1.

  Since the liquid crystal aligning agent of the present invention contains the specific component (A) and component (B), the voltage holding ratio is high while maintaining the rubbing resistance, which has been a conventionally required characteristic, and in the present age. It is possible to form a liquid crystal alignment film that has a very small charge accumulation to meet even strict requirements.

The present invention is described in detail below.
The liquid crystal aligning agent of this invention contains the said (A) component and the said (B) component. The liquid crystal alignment agent is a solution for producing a liquid crystal alignment film, and the liquid crystal alignment film is a film for aligning liquid crystals in a predetermined direction. Each component contained in the liquid crystal aligning agent of this invention is explained in full detail below.

<(A) component>
The component (A) contained in the liquid crystal aligning agent of the present invention is selected from a polyimide precursor obtained by polymerizing a tetracarboxylic acid component and a diamine component, and a polyimide obtained by imidizing this polyimide precursor. At least one polymer. Examples of the polyimide precursor include polyamic acid (also referred to as polyamic acid), polyamic acid ester, and the like.

  In the component (A), the tetracarboxylic acid component is 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride (hereinafter also referred to as “TDA”). 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid diester (hereinafter also referred to as “TDA diester”), and 3,4-dicarboxy-1,2,3, It contains at least one selected from 4-tetrahydro-1-naphthalene succinic diester dichloride (hereinafter also referred to as “TDA diester dichloride”). Therefore, although mentioned later in detail, the polymer of the component (A) is a polymer having a tetravalent structure represented by the following formula (4) derived from TDA, TDA diester or TDA diester dichloride.

  In the component (A), the content of the total amount of TDA, TDA diester and TDA diester dichloride with respect to the total amount of the tetracarboxylic acid component is, for example, 20 to 100 mol%, preferably 40 to 100 mol%.

Furthermore, in the component (A), the diamine component to be polymerized with the tetracarboxylic acid component includes a diamine having a side chain represented by the above formula (1). The main chain of diamine is a structure connecting two amino groups of diamine, and the side chain of diamine is a structure branched from a structure connecting two amino groups of diamine. Therefore, since the polymer of the component (A) includes a diamine having a side chain represented by the formula (1) as a raw material diamine component, the polymer of the component (A) is, for example, It has a benzene ring in the main chain, ^-P 1 bound to the benzene ring _{^{- (Q 1) p - (}} Q 2) q - (Q 3) is a structure having r -P ² as a side chain.

In the side chain represented by the formula (1), a TN (Twisted Nematic) mode in which a relatively low pretilt angle of 3 to 5 ° is required, or an OCB (Optically Compensated Bend) in which a pretilt of 8 to 20 ° is required. In the mode or the like, a side chain (-P ^1- (Q ¹ ) _p- (Q ² ) _q- (Q ³ ) _r -P ² ) having a relatively low tilting ability is preferable.

As a structure having a relatively small ability to develop a tilt, in formula (1), P ¹ is preferably —O—, —NHCO— or —CONH—, p is 0 to 1, q is 0 to 1, and r is 0. When p and / or q is 1, P ² is preferably a linear alkyl having 1 to 12 carbon atoms, and when p = q = r = 0, P ² is a linear alkyl having 10 to 22 carbon atoms. A divalent organic group selected from a C12-25 organic group having a group or a steroid skeleton is preferred. Specific examples of the structure of the side chain having a small tilting ability are shown in Table 1, but are not limited thereto. In this specification, the organic group is, for example, —O—, —NHCO—, —CONH—, —COO—, or a hydrocarbon group which may have N or O.

  From the viewpoint of electrical characteristics, a diamine having a long-chain alkyl side chain as shown in [1-1] of Table 1 is preferable, and is represented by [1-9] of Table 1 from the viewpoint of liquid crystal alignment and pretilt stability. Diamines having side chains are preferred.

On the other hand, in the VA (Vertical Alignment) mode and the like, vertical alignment can be obtained by using a side chain having a large tilting ability. As a preferable structure of the formula (1) in the VA mode, in the formula, P ¹ is preferably —O—, —COO—, or —CH ₂ O—, p is 0 to 1, q is 0 to 1, and r is 0-1 are preferred, ^{P 2} is preferably 2 to 22. In the case of p = q = r = 0, P ² is preferably a linear alkyl group having 18 to 22 carbon atoms or a divalent organic group that is an organic group having 12 to 25 carbon atoms having a steroid skeleton. Specific structures of side chains having a large tilting ability are shown in Tables 2-1 and 2-2.

  These side chains have a high tilting ability and are preferable when used in the VA mode. In particular, diamines having side chains such as [1-15] and [1-31] are preferable because they have a high tilting ability and exhibit vertical alignment with a relatively small amount of side chains. The diamine having a side chain of 1-34] is preferable in terms of printability of the liquid crystal aligning agent because it has a very high ability to develop a tilt and can achieve vertical alignment with a very small amount of side chain.

On the other hand, in the diamine having a side chain represented by the formula (1), P ¹ is preferably —NHCO—, and P ² is preferably an alkyl group having 1 to 16 carbon atoms, preferably 3 to 10 carbon atoms. Further, Q ¹ , Q ² , Q ³ and p, q, r are appropriately combined. Also, ^-P 1 according diamine having a benzene ring in the main chain, bonded to the benzene ring _{^{- (Q 1) P - (}} Q 2) q - (Q 3) structure with r -P ² as a side chain , The position of each substituent on the benzene ring is not particularly limited, but the positional relationship between the two amino groups is preferably meta or para.

  Examples of the diamine having a side chain represented by the above formula (1) include the following [DA-1] to [DA-26].

（式［ＤＡ−１］から式［ＤＡ−５］中、Ｒ_６は、炭素数１〜２２のアルキル基またはフッ素含有アルキル基である。）

(In Formula [DA-1] to Formula [DA-5], R ₆ is an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group.)

（式［ＤＡ−６］から式［ＤＡ−９］中、Ｓ_５は、それぞれ同一でも異なっていてもよく、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＨ_２−、−Ｏ−、−ＣＯ−、または−ＮＨ−を示し、Ｒ_６は炭素数１〜２２のアルキル基またはフッ素含有アルキル基を示す。）

(In the formulas [DA-6] to [DA-9], S _{5 s} may be the same as or different from each other, and —COO—, —OCO—, —CONH—, —NHCO—, —CH ₂ —, -O-, -CO-, or -NH- is represented, and R ₆ represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group.

（式［ＤＡ−１０］および式［ＤＡ−１１］中、Ｓ_６は、−Ｏ−、−ＯＣＨ_２−、−ＣＨ_２Ｏ−、−ＣＯＯＣＨ_２−、または−ＣＨ_２ＯＣＯ−を示し、Ｒ_７は炭素数１〜２２のアルキル基、アルコキシ基、フッ素含有アルキル基またはフッ素含有アルコキシ基である。）

(In Formula [DA-10] and Formula [DA-11], S ₆ represents —O—, —OCH ₂ —, —CH ₂ O—, —COOCH ₂ —, or —CH ₂ OCO—, and R ₇ is an alkyl group having 1 to 22 carbon atoms, an alkoxy group, a fluorine-containing alkyl group or a fluorine-containing alkoxy group.

（式［ＤＡ−１２］から式［ＤＡ−１４］中、Ｓ_７は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、または−ＣＨ_２−を示し、Ｒ_８は炭素数１〜２２のアルキル基、アルコキシ基、フッ素含有アルキル基またはフッ素含有アルコキシ基である。）

(In the formulas [DA-12] to [DA-14], S ₇ represents —COO—, —OCO—, —CONH—, —NHCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH _2. O—, —OCH ₂ —, or —CH ₂ — is represented, and R ₈ represents an alkyl group having 1 to 22 carbon atoms, an alkoxy group, a fluorine-containing alkyl group, or a fluorine-containing alkoxy group.

（式［ＤＡ−１５］および式［ＤＡ−１６］中、Ｓ_８は、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−ＣＯＯＣＨ_２−、−ＣＨ_２ＯＣＯ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、−ＣＨ_２−、−Ｏ−、または−ＮＨ−を示し、Ｒ_９はフッ素基、シアノ基、トリフルオロメタン基、ニトロ基、アゾ基、ホルミル基、アセチル基、アセトキシ基、または水酸基である。）

(In Formula [DA-15] and Formula [DA-16], S ₈ represents —COO—, —OCO—, —CONH—, —NHCO—, —COOCH ₂ —, —CH ₂ OCO—, —CH _2. O—, —OCH ₂ —, —CH ₂ —, —O—, or —NH—, and R ₉ 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. Group or hydroxyl group.)

（式［ＤＡ−１７］から式［ＤＡ−２０］中、Ｒ_１０は炭素数３〜１２のアルキル基であり、１，４−シクロへキシレンのシス−トランス異性は、それぞれトランス体である。）

(In the formulas [DA-17] to [DA-20], R ₁₀ is an alkyl group having 3 to 12 carbon atoms, and the cis-trans isomerism of 1,4-cyclohexylene is a trans isomer. )

  The content of the diamine having a side chain represented by the above formula (1) is preferably 5 to 50 mol% with respect to the total amount of the diamine component, and 5 to 30 mol% from the viewpoint of pretilt uniformity and printability. Is particularly preferred.

In the component (A), the diamine having a side chain represented by the formula (1) is a diamine represented by the above formula (3), that is, the main chain has a benzene ring, and is bonded to the benzene ring. the _{^{-P 1 - (Q 1) p}} - (Q 2) q - (Q 3) diamine is a structure having r -P ² as a side chain is preferable from the viewpoint of availability and the like.

  In the diamine represented by the formula (3), the position of each substituent on the benzene ring is not particularly limited, but the positional relationship between the two amino groups is preferably meta or para.

  The tetracarboxylic acid component which is the raw material of the component (A) may contain other tetracarboxylic acid derivatives other than the above-mentioned TDA, TDA diester and TDA diester dichloride. Examples of other tetracarboxylic acid derivatives in the component (A) include the following tetracarboxylic dianhydrides.

Examples of the tetracarboxylic dianhydride having an alicyclic structure or an aliphatic structure include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutane. Tetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetra Carboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic Acid dianhydride, 3,4-dicarboxy-1-cyclohexylsuccinic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, bicyclo [3.3.0] octane-2,4 6,8-tetracarboxylic dianhydride, 3,3 ′, 4,4′-dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, cis-3,7-dibutyl Cycloocta-1,5-diene-1,2,5,6-tetracarboxylic dianhydride, tricyclo [4.2.1.0 ^2,5 ] nonane-3,4,7,8-tetracarboxylic acid -3, 4: 7,8-dianhydride, 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-dianhydride, and the like.

  As aromatic tetracarboxylic dianhydride, pyromellitic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic acid Dianhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,3,3 ′, 4′- Benzophenonetetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid A dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride etc. are mentioned.

  The tetracarboxylic dianhydride may be used alone or in combination of two or more depending on the liquid crystal alignment properties of the liquid crystal alignment film to be formed, such as voltage holding characteristics and accumulated charges.

  Moreover, tetracarboxylic acid dialkyl ester and tetracarboxylic acid dialkyl diester dichloride are mentioned as another tetracarboxylic acid derivative which the tetracarboxylic acid component which is the raw material of the component (A) may contain. When the tetracarboxylic acid component contains such a tetracarboxylic acid dialkyl ester or tetracarboxylic acid dialkyl ester dichloride, the polymer becomes a polyamic acid ester that is a polyimide precursor. The tetracarboxylic acid dialkyl ester that can be used is not particularly limited, and examples thereof include aliphatic tetracarboxylic acid diesters and aromatic tetracarboxylic acid dialkyl esters. 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 1,2,3,4-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'-dicyclohexyl tetracarboxylic 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-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.

  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-Naphthalenetetracarboxylic acid dialkyl ester Tel and the like.

  Moreover, the tetracarboxylic-acid dialkyl diester dichloride as another tetracarboxylic acid derivative which the tetracarboxylic-acid component which is a raw material of (A) component may contain includes the dichloride of the said tetracarboxylic-acid diester.

  In the component (A), the content of the total amount of other tetracarboxylic acid derivatives other than TDA, TDA diester and TDA diester dichloride with respect to the total amount of the tetracarboxylic acid component is preferably 0 to 80 mol%, more preferably 0 to 40 mol. %.

  Moreover, the diamine component which is a raw material of (A) component may contain other diamine other than the diamine which has a side chain represented by the said Formula (1). Examples of such other diamines in the component (A) include the following alicyclic diamines, aromatic diamines, heterocyclic diamines, aliphatic diamines and urea bond-containing diamines.

  Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4′-diaminodicyclohexylmethane, 4,4′-diamino-3,3′-dimethyldicyclohexylamine, and isophorone diamine. Etc.

  Examples of aromatic diamines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 3,5-diaminotoluene, 1,4-diamino- 2-methoxybenzene, 2,5-diamino-p-xylene, 1,3-diamino-4-chlorobenzene, 3,5-diaminobenzoic acid, 1,4-diamino-2,5-dichlorobenzene, 4,4 ′ -Diamino-1,2-diphenylethane, 4,4'-diamino-2,2'-dimethylbibenzyl, 4,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 2,2'-diaminostilbene, 4,4'-diamino Tilben, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl sulfide, 4,4′-diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfone, 4,4′- Diaminobenzophenone, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 3,5-bis (4- Aminophenoxy) benzoic acid, 4,4′-bis (4-aminophenoxy) bibenzyl, 2,2-bis [(4-aminophenoxy) methyl] propane, 2,2-bis [4- (4-aminophenoxy) Phenyl] hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, bi [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, 1,1-bis (4-aminophenyl) cyclohexane, α, α′-bis (4-amino Phenyl) -1,4-diisopropylbenzene, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis (3-aminophenyl) hexafluoropropane, 2,2-bis (4-aminophenyl) hexa Fluoropropane, 4,4′-diaminodiphenylamine, 2,4-diaminodiphenylamine, 1,8-diaminonaphthalene, 1,5-diaminonaphthalene, 1,5-diaminoanthraquinone, 1,3-diaminopyrene, 1,6- Diaminopyrene, 1,8-diaminopyrene, 2,7-diaminofluorene, 1,3-bis (4-aminophenyl) Nyl) tetramethyldisiloxane, benzidine, 2,2′-dimethylbenzidine, 1,2-bis (4-aminophenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,4-bis (4 -Aminophenyl) butane, 1,5-bis (4-aminophenyl) pentane, 1,6-bis (4-aminophenyl) hexane, 1,7-bis (4-aminophenyl) heptane, 1,8-bis (4-aminophenyl) octane, 1,9-bis (4-aminophenyl) nonane, 1,10-bis (4-aminophenyl) decane, 1,3-bis (4-aminophenoxy) propane, 1,4 -Bis (4-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,7-bis (4-a Minophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,10-bis (4-aminophenoxy) decane, di (4-aminophenyl) ) Propane-1,3-dioate, di (4-aminophenyl) butane-1,4-dioate, di (4-aminophenyl) pentane-1,5-dioate, di (4-aminophenyl) hexane-1, 6-dioate, di (4-aminophenyl) heptane-1,7-dioate, di (4-aminophenyl) octane-1,8-dioate, di (4-aminophenyl) nonane-1,9-dioate, di (4-aminophenyl) decane-1,10-dioate, 1,3-bis [4- (4-aminophenoxy) phenoxy] propane, 1,4-bis 4- (4-aminophenoxy) phenoxy] butane, 1,5-bis [4- (4-aminophenoxy) phenoxy] pentane, 1,6-bis [4- (4-aminophenoxy) phenoxy] hexane, 1, 7-bis [4- (4-aminophenoxy) phenoxy] heptane, 1,8-bis [4- (4-aminophenoxy) phenoxy] octane, 1,9-bis [4- (4-aminophenoxy) phenoxy] Nonane, 1,10-bis [4- (4-aminophenoxy) phenoxy] decane and the like can be mentioned.

  Examples of aromatic-aliphatic diamines include diamines represented by the following formula [DAM].

（式［ＤＡＭ］中、Ａｒはベンゼン環またはナフタレン環を表し、Ｒ_１は炭素原子数が１〜５のアルキレン基であり、Ｒ_２は水素原子またはメチル基である。

(In the formula [DAM], Ar represents a benzene ring or a naphthalene ring, R ₁ represents an alkylene group having 1 to 5 carbon atoms, and R ₂ represents a hydrogen atom or a methyl group.

  Specific examples of the aromatic-aliphatic diamine include 3-aminobenzylamine, 4-aminobenzylamine, 3-amino-N-methylbenzylamine, 4-amino-N-methylbenzylamine, 3-aminophenethylamine, 4 -Aminophenethylamine, 3-amino-N-methylphenethylamine, 4-amino-N-methylphenethylamine, 3- (3-aminopropyl) aniline, 4- (3-aminopropyl) aniline, 3- (3-methylaminopropyl) ) Aniline, 4- (3-methylaminopropyl) aniline, 3- (4-aminobutyl) aniline, 4- (4-aminobutyl) aniline, 3- (4-methylaminobutyl) aniline, 4- (4- Methylaminobutyl) aniline, 3- (5-aminopentyl) aniline, 4- (5-aminopenti) ) Aniline, 3- (5-methylaminopentyl) aniline, 4- (5-methylaminopentyl) aniline, 2- (6-aminonaphthyl) methylamine, 3- (6-aminonaphthyl) methylamine, 2- ( 6-aminonaphthyl) ethylamine, 3- (6-aminonaphthyl) ethylamine and the like.

  Examples of heterocyclic diamines include 2,6-diaminopyridine, 2,4-diaminopyridine, 2,4-diamino-1,3,5-triazine, 2,7-diaminodibenzofuran, 3,6-diaminocarbazole 2,4-diamino-6-isopropyl-1,3,5-triazine, 2,5-bis (4-aminophenyl) -1,3,4-oxadiazole and the like.

  Examples of aliphatic diamines include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7- Diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1,9-diamino-5-methylnonane, 1,12-diaminododecane, Examples include 1,18-diaminooctadecane and 1,2-bis (3-aminopropoxy) ethane.

  Examples of urea bond-containing diamines include N, N′-bis (4-aminophenethyl) urea.

  Moreover, the diamine component in (A) component may contain the following diamines.

  In the formula [DA-31], m is an integer of 0 to 3, and in the formula [DA-34], n is an integer of 1 to 5. By introducing [DA-27] and [DA-28], the voltage holding ratio (also referred to as VHR) of the liquid crystal display element using the liquid crystal alignment film formed from the liquid crystal aligning agent of the present invention is further improved. be able to. [DA-29] to [DA-34] are preferable because they are effective in reducing the accumulated charge of the liquid crystal display element.

  In addition, examples of the diamine component in the component (A) include diaminosiloxanes represented by the following formula [DA-35].

（式［ＤＡ−３５］中、ｍは、１から１０の整数である。）

(In the formula [DA-35], m is an integer of 1 to 10.)

  The diamine component in these components (A) can be used alone or in combination of two or more depending on the liquid crystal alignment properties, voltage holding characteristics, accumulated charge, and the like when the liquid crystal alignment film is formed. The mixing ratio is not limited.

  In addition, the molecular weight of the polymer (polyimide precursor, polyimide) of the component (A) is determined by considering the strength of the obtained liquid crystal alignment film, the workability when forming the liquid crystal alignment film, and the uniformity of the liquid crystal alignment film. The weight average molecular weight measured by the Gel Permeation Chromatography method is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

  In addition, it is preferable that the polymer of (A) component is a polyimide. The component (A) tends to exist on the surface of the liquid crystal alignment film (that is, the side opposite to the substrate) when the liquid crystal alignment film is formed, and the polymer present on the surface of the liquid crystal alignment film touches the liquid crystal and directly affects the value of VHR. This is because it is better to have many imide groups that do not cause a reversible reaction in order to contribute. Moreover, it is preferable that the imidation ratio of this polyimide is 60 to 90%.

<(B) component>
The component (B) contained in the liquid crystal aligning agent of the present invention is selected from a polyimide precursor obtained by polymerizing a tetracarboxylic acid component and a diamine component, and a polyimide obtained by imidizing this polyimide precursor. At least one polymer. Examples of the polyimide precursor include polyamic acid (also referred to as polyamic acid), polyamic acid ester, and the like.

  In the component (B), the tetracarboxylic acid component is 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, 3,4-dicarboxy-1 , 2,3,4-tetrahydro-1-naphthalene succinic acid diester and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid diester dichloride. Therefore, as will be described in detail later, the polymer of component (B) is also a polymer having a tetravalent structure represented by the above formula (4) derived from TDA, TDA diester or TDA diester dichloride.

  In the component (B), the total content of TDA, TDA diester and TDA diester dichloride with respect to the total amount of the tetracarboxylic acid component is 20 to 100 mol%, preferably 40 to 100 mol%.

Furthermore, in the component (B), the diamine component that undergoes a polymerization reaction with the tetracarboxylic acid component is a —CR ²¹ ₂ — group in the main chain (wherein two R ²¹ each independently represents a hydrogen atom or an organic group). It consists only of a diamine (hereinafter also referred to as “diamine having a —CR ²¹ ₂ — group in the main chain”) having two R ²¹ together to form a cyclic structure. As long as the diamine has a —CR ²¹ ₂ — group in the main chain, one kind or two or more kinds may be used in combination. The polymer of the component (B) is only a diamine having a —CR ²¹ ₂ — group in the main chain as the starting diamine component, and will be described in detail later. However, the polymer of the component (B) is —CR in the main chain. ^The structure has ²¹ ₂ −. The main chain of diamine is a structure that connects two amino groups of diamine. Further, the ^{-CR 21} ₂ - Examples of the organic group of group ^{R 21,} an alkyl group having 1 to 5 carbon atoms, fluoroalkyl group having 1 to 5 carbon atoms, and a fluorine atom. Moreover, two R < ²¹ > may join together and form a cyclic structure by forming a C2-C7 alkylene group, for example.

Examples of the diamine having a —CR ²¹ ₂ — group in the main chain include the following alicyclic diamines, aromatic diamines, aromatic-aliphatic diamines, aliphatic diamines, urea bond-containing diamines, and the like.

  Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4′-diaminodicyclohexylmethane, 4,4′-diamino-3,3′-dimethyldicyclohexylamine, and isophorone diamine. Etc.

  Examples of aromatic diamines include 4,4′-diamino-1,2-diphenylethane, 4,4′-diamino-2,2′-dimethylbibenzyl, 4,4′-diaminodiphenylmethane, 3,3 ′. -Diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 2,2-bis [(4-aminophenoxy) methyl] propane, 2,2-bis [4 -(4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 1,1-bis (4-aminophenyl) cyclohexane, α, α'-bis (4-aminophenyl) -1,4-diisopropylbenzene, 2,2-bis (3-aminophenyl) hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 1,2-bis (4-aminophenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,4-bis (4-aminophenyl) butane, , 5-bis (4-aminophenyl) pentane, 1,6-bis (4-aminophenyl) hexane, 1,7-bis (4-aminophenyl) heptane, 1,8-bis (4-aminophenyl) octane 1,9-bis (4-aminophenyl) nonane, 1,10-bis (4-aminophenyl) decane, 1,3-bis (4-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) ) Butane, 1,5-bis (4-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1, -Bis (4-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,10-bis (4-aminophenoxy) decane, di (4-aminophenyl) propane-1,3-dioate Di (4-aminophenyl) butane-1,4-dioate, di (4-aminophenyl) pentane-1,5-dioate, di (4-aminophenyl) hexane-1,6-dioate, di (4- Aminophenyl) heptane-1,7-dioate, di (4-aminophenyl) octane-1,8-dioate, di (4-aminophenyl) nonane-1,9-dioate, di (4-aminophenyl) decane- 1,10-dioate, 1,3-bis [4- (4-aminophenoxy) phenoxy] propane, 1,4-bis [4- (4-aminophenoxy) Enoxy] butane, 1,5-bis [4- (4-aminophenoxy) phenoxy] pentane, 1,6-bis [4- (4-aminophenoxy) phenoxy] hexane, 1,7-bis [4- (4 -Aminophenoxy) phenoxy] heptane, 1,8-bis [4- (4-aminophenoxy) phenoxy] octane, 1,9-bis [4- (4-aminophenoxy) phenoxy] nonane, 1,10-bis [ 4- (4-aminophenoxy) phenoxy] decane and the like.

  Examples of aromatic-aliphatic diamines include diamines represented by the following formula [DAM].

（式［ＤＡＭ］中、Ａｒはベンゼン環またはナフタレン環を表し、Ｒ_１は炭素原子数が１〜５のアルキレン基であり、Ｒ_２は水素原子またはメチル基である。）

(In the formula [DAM], Ar represents a benzene ring or a naphthalene ring, R ₁ is an alkylene group having 1 to 5 carbon atoms, and R ₂ is a hydrogen atom or a methyl group.)

  Specific examples of the aromatic-aliphatic diamine include 3-aminobenzylamine, 4-aminobenzylamine, 3-amino-N-methylbenzylamine, 4-amino-N-methylbenzylamine, 3-aminophenethylamine, 4 -Aminophenethylamine, 3-amino-N-methylphenethylamine, 4-amino-N-methylphenethylamine, 3- (3-aminopropyl) aniline, 4- (3-aminopropyl) aniline, 3- (3-methylaminopropyl) ) Aniline, 4- (3-methylaminopropyl) aniline, 3- (4-aminobutyl) aniline, 4- (4-aminobutyl) aniline, 3- (4-methylaminobutyl) aniline, 4- (4- Methylaminobutyl) aniline, 3- (5-aminopentyl) aniline, 4- (5-aminopenti) ) Aniline, 3- (5-methylaminopentyl) aniline, 4- (5-methylaminopentyl) aniline, 2- (6-aminonaphthyl) methylamine, 3- (6-aminonaphthyl) methylamine, 2- ( 6-aminonaphthyl) ethylamine, 3- (6-aminonaphthyl) ethylamine and the like.

  Examples of aliphatic diamines include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7- Diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1,9-diamino-5-methylnonane, 1,12-diaminododecane, Examples include 1,18-diaminooctadecane and 1,2-bis (3-aminopropoxy) ethane.

  Examples of urea bond-containing diamines include N, N′-bis (4-aminophenethyl) urea.

Incidentally, -CR 21 ² in the main chain in the component (B) _- Examples of the diamine having a group, the diamine represented by the above formula (2) is preferable in terms of availability and the like. Examples of such a diamine include diamines exemplified as aromatic diamines in the description of the component (B).

Thus obtained by polymerizing a diamine having a —CR ²¹ ₂ — group in the main chain and a tetracarboxylic acid component containing TDA, TDA diester or TDA diester dichloride (hereinafter also referred to as “TDA etc.”). It is estimated that a liquid crystal alignment film having a very high resistance can be obtained by including a polyimide precursor or polyimide in the liquid crystal aligning agent together with the component (A). This liquid crystal alignment film having a very high resistance is less likely to cause a current to flow when a voltage is applied than a liquid crystal alignment agent having a low resistance. It is presumed that a liquid crystal alignment film having a very small value was obtained. Note that since the accumulated charge itself is very small, it takes a long time for the accumulated charge to escape, and there is no conventional problem that an afterimage or display burn-in occurs.

  The tetracarboxylic acid component which is the raw material of the component (B) may contain other tetracarboxylic acid derivatives other than the TDA, TDA diester and TDA diester dichloride. Such other tetracarboxylic acid derivatives in the component (B) include other tetracarboxylic acid derivatives in the component (A).

  In the component (B), the content of the total amount of other tetracarboxylic acid derivatives other than TDA, TDA diester and TDA diester dichloride with respect to the total amount of the tetracarboxylic acid component is preferably 0 to 80 mol%, more preferably 0 to 60 mol. %.

  The tetracarboxylic acid component in the component (B) may be the same as or different from the tetracarboxylic acid component in the component (A).

  In addition, the molecular weight of the polymer (polyimide precursor, polyimide) of the component (A) is determined by considering the strength of the obtained liquid crystal alignment film, the workability when forming the liquid crystal alignment film, and the uniformity of the liquid crystal alignment film. The weight average molecular weight measured by the Gel Permeation Chromatography method is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

  The polymer of component (B) is preferably a polyimide precursor. This is because the component (B) tends to exist on the side of the substrate on which the liquid crystal aligning agent is applied (that is, the side opposite to the surface of the liquid crystal alignment film) when the liquid crystal alignment film is formed. This is because having a large number of polar groups provides good adhesion to the substrate and excellent printability.

  The ratio of the component (A) and the component (B) contained in the liquid crystal aligning agent of the present invention is not particularly limited. For example, in terms of mass ratio, (A) component: (B) component = 5-50: 95-50, Preferably (A) component: (B) component = 5-30: 95-70 by mass ratio.

Thus, the liquid crystal aligning agent of this invention is a polymer obtained by making the tetracarboxylic-acid component containing TDA etc. react with the diamine component containing the diamine which has a side chain represented by the said Formula (1). Specific (B) which is a polymer obtained by reacting a specific (A) component, a tetracarboxylic acid component containing TDA or the like, and a diamine component consisting only of a diamine having a —CR ²¹ ₂ — group in the main chain Since it contains components, as shown in the examples to be described later, while maintaining the rubbing resistance, which has been required conventionally, it has a high voltage holding ratio and also has a charge storage enough to meet the strict demands of today. It is possible to form a liquid crystal alignment film having a very small. Therefore, features that are not often seen in other applications, such as frequent display on-off (or frequent backlight on-off) and being watched by users from the moment they are displayed. The display screen can be suitably used for mobile phones and tablet terminals.

Such an effect of the present invention is a specific polymer obtained by reacting a tetracarboxylic acid component containing TDA or the like and a diamine component containing a diamine having a side chain represented by the above formula (1) ( A specific component (B) which is a polymer obtained by reacting the component A) with a tetracarboxylic acid component containing TDA or the like and a diamine component consisting only of a diamine having a —CR ²¹ ₂ — group in the main chain. This is an effect exhibited for the first time when the liquid crystal aligning agent is contained. For example, when a polymer that does not use TDA or the like as a raw material is used, the RDC is large, that is, the charge accumulation is large, and the rubbing resistance is not good, and the effect of the liquid crystal aligning agent of the present invention cannot be exhibited. In addition, the component (B) also has a large RDC when a polymer that does not use TDA or the like as a raw material is used. Even when TDA or the like is used as a raw material, if a diamine having no —CR ²¹ ₂ — in the main chain is used as the diamine component of the raw material, the RDC is large.

  In order to obtain the polymer of the above component (A) and the polymer of the component (B) by a polymerization reaction of the tetracarboxylic acid component and the diamine component of each raw material, a known synthesis method can be used. In general, the tetracarboxylic acid component and the diamine component are reacted in an organic solvent. The reaction between the tetracarboxylic acid component and the diamine component is advantageous in that it proceeds relatively easily in an organic solvent and no by-products are generated.

  The organic solvent used for the reaction between the tetracarboxylic acid component and the diamine component is not particularly limited as long as the generated polyamic acid dissolves. Specific examples are given below.

  N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethyl urea, pyridine, dimethyl sulfone, 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-methoxypropionate Propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 3-methoxy-N, N-dimethylpropanamide, 3-ethoxy-N, N-dimethyl Examples include propanamide and 3-butoxy-N, N-dimethylpropanamide. These may be used alone or in combination. Furthermore, even if the solvent does not dissolve the polyamic acid, it may be used by mixing with the above solvent as long as the produced polyamic acid does not precipitate.

  In addition, since water in the organic solvent inhibits the polymerization reaction and further causes hydrolysis of the generated polyamic acid, it is preferable to use a dehydrated and dried organic solvent as much as possible.

  When the tetracarboxylic acid component and the diamine 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. On the contrary, 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. Any method may be used. In addition, when the tetracarboxylic acid component or diamine component is composed of a plurality of types of compounds, they may be reacted in a premixed state, may be individually reacted sequentially, or may be mixed with individually reacted low molecular weight substances. It is good also as a high molecular weight body by making it react.

  The polymerization temperature at that time can be selected from an arbitrary temperature of -20 ° C to 150 ° C, preferably in the range of -5 ° C to 100 ° C. The reaction can be carried out at any concentration, but if the concentration is too low, it is difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution becomes too high and uniform stirring is difficult. Therefore, the total concentration of the tetracarboxylic acid component and the diamine component in the reaction solution is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The initial stage of the reaction is carried out at a high concentration, and then an organic solvent can be added.

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

  The polyimide can be obtained by dehydrating and ring-closing the polyimide precursor such as the polyamic acid or polyamic acid ester. In polyimide, the dehydration cyclization rate (imidation rate) of the amic acid group is not necessarily 100%, and can be arbitrarily adjusted in the range of 0% to 100% depending on the application and purpose.

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

  The temperature when polyamic acid or polyamic acid ester is thermally imidized in a solution is 100 ° C. to 400 ° C., preferably 120 ° C. to 250 ° C., and is performed while removing water generated by the imidation reaction from the system. Is preferred.

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

  In addition, as a method for synthesizing a polyamic acid ester, a tetracarboxylic acid diester dichloride obtained by reacting the tetracarboxylic acid diester with a halogenating agent such as thionyl chloride, sulfuryl chloride, oxalyl chloride, phosphorus oxychloride, and a diamine component are used. And a method of reacting a tetracarboxylic acid diester and a diamine component in the presence of a suitable condensing agent and a base. Alternatively, it can also be obtained by polymerizing a polyamic acid in advance and esterifying the carboxylic acid in the amic acid using a polymer reaction.

  Specifically, tetracarboxylic acid diester dichloride and diamine in the presence of a base and an organic solvent are −20 ° C. to 150 ° C., preferably 0 ° C. to 50 ° C., 30 minutes to 24 hours, preferably 1 to 4 hours. It can be synthesized by reacting.

  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.

  When conducting condensation polymerization in the presence of a condensing agent, 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- (benzotriazole-1- Yl) -N, N, N ′, N′-tetramethyluronium hexafluorophosphate, (2,3-dihydro-2-thioxo-3-benzoxazolyl) phosphonate diphenyl, 4- (4,6 -Dimethoxy-1,3,5-triazin-2-yl) 4-methoxymorpholium chloride n-hydrate Yes.

  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 tetracarboxylic acid diester.

  The solvent used in the above reaction can be the solvent used when polymerizing the polyamic acid shown above, but N-methyl-2-pyrrolidone and γ-butyrolactone are preferred from the solubility of the monomer and polymer. These may be used alone or in combination of two or more. The concentration at the time of synthesis is preferably 1 to 30% by mass and more preferably 5 to 20% by mass from the viewpoint that polymer precipitation is unlikely to occur and a high molecular weight body is easily obtained. 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.

  When recovering the polyimide precursor such as polyamic acid, polyamic acid ester, polyimide precursor such as polyamic acid, polyamic acid ester, and polyimide reaction solution, polyimide, and polyimide, the reaction solution is poured into a poor solvent. It can be 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 precipitated in a poor solvent and collected by filtration can be dried at normal temperature or under reduced pressure at room temperature or by heating. Moreover, when the polymer which carried out precipitation collection | recovery is re-dissolved in an organic solvent and the operation which carries out reprecipitation collection | recovery is repeated 2 to 10 times, the impurity in a polymer can be decreased. Examples of the poor solvent at this time include alcohols, ketones, hydrocarbons and the like, and it is preferable to use three or more kinds of poor solvents selected from these because purification efficiency is further improved.

  The polyimide precursor obtained by polymerizing such a tetracarboxylic acid component and a diamine component is, for example, a polymer having a repeating unit represented by the following formula [a]. A polyimide obtained by dehydrating and ring-closing a polyimide precursor having such a repeating unit is polyimide.

（式［ａ］中、Ｒ_１１は、原料のテトラカルボン酸成分（例えば下記式（ｃ））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（例えば下記式（ｂ））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 a raw material tetracarboxylic acid component (eg, the following formula (c)), and R ₁₂ is a raw material diamine component (eg, the following formula (b )) Is a divalent organic group, A ₁₁ and A ₁₂ are a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, which may be the same or different, and j is a positive integer. Is shown.)

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], since R ₁₁ is a group derived from a tetracarboxylic acid component as a raw material, the polyimide precursor of the component (A) and the component (B) is represented by R ₁₁ in the above formula (4). Has a structure. In addition, since R ₁₂ is a group derived from a diamine component as a raw material, the polyimide precursor of component (A) is R ₁₂ is -P ^1- (Q ¹ ) _p- (Q ² ) _q- (Q ³ ) It has a side chain represented by _r— P ² , and the polyimide precursor of component (B) has R ₁₂ having —CR ²¹ ₂ — in the main chain.

（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].)

  The liquid crystal aligning agent of this invention contains an organic solvent in addition to above-described (A) component and (B) component. And the liquid crystal aligning agent of this invention is a form of the solution which said (A) component and (B) component melt | dissolved in the organic solvent.

  As long as the liquid crystal aligning agent of this invention has the form of the solution in which (A) component and (B) component were melt | dissolved in the organic solvent, the manufacture is not ask | required. For example, a method of mixing the powder of the component (A) and the component (B) and dissolving in an organic solvent, a method of mixing the powder of the component (A) and the solution of the component (B), and a solution of the component (A) ( There are a method of mixing the powder of component B) and a method of mixing the solution of component (A) and the solution of component (B). Even when the good solvent in which the component (A) is dissolved differs from the good solvent in which the component (B) is dissolved, a uniform mixed solution of the component (A) and the component (B) can be obtained. A method of mixing the solution and the solution of component (B) is more preferable.

  Here, the solution of the component (A) or the solution of the component (B) may be the reaction solution obtained when the component (A) or the component (B) is synthesized in an organic solvent, The reaction solution may be diluted with an appropriate solvent. Moreover, when (A) component and (B) component are obtained as a powder, this may be dissolved in an organic solvent to form a solution.

  The said organic solvent contained in the liquid crystal aligning agent of this invention will not be specifically limited if (A) component and (B) component melt | dissolve uniformly. Specific examples thereof include N, N-dimethylformamide, N, N-diethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-methylcaprolactam, Examples include 2-pyrrolidone, N-vinyl-2-pyrrolidone, dimethyl sulfoxide, dimethyl sulfone, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide and the like. You may use these 1 type or in mixture of 2 or more types. Moreover, even if it is a solvent which cannot melt | dissolve (A) component and (B) component uniformly independently, if it is a range in which (A) component and (B) component do not precipitate, it may mix with said organic solvent. Good.

  The liquid crystal aligning agent of the present invention contains, in addition to the above, other polymers other than the component (A) and the component (B) as the polymer component as long as the effects of the present invention are not impaired. May be. Examples of such other polymers include polyamic acid, polyamic acid ester, polyimide, and polyamide that do not use any of TDA, TDA diester, and TDA diester dichloride as raw materials.

  The content (concentration) of the polymer component contained in the liquid crystal aligning agent of the present invention can be appropriately changed depending on the thickness of the liquid crystal alignment film (polyimide film) to be formed. From the viewpoint of forming a film, the content of the polymer component with respect to the organic solvent is preferably 0.5% by mass or more, and preferably 15% by mass or less, more preferably from the viewpoint of storage stability of the solution. 1 to 10% by mass. In this case, a concentrated solution of the polymer component may be prepared in advance and diluted when the liquid crystal aligning agent is prepared from the concentrated solution. The concentration of the concentrated solution of the polymer component is preferably 10 to 30% by mass, and more preferably 10 to 15% by mass. Alternatively, the polymer component powder may be heated when the solution is prepared by dissolving the powder in an organic solvent. The heating temperature is preferably 20 ° C to 150 ° C, particularly preferably 20 ° C to 80 ° C. Moreover, when other polymers other than (A) component and (B) component are also contained, content of polymers other than (A) component and (B) component in a polymer component is 0. It is 5 mass%-15 mass%, Preferably it is 1 mass%-10 mass%.

  Moreover, the liquid crystal aligning agent of this invention may contain components other than a polymer component. Examples thereof include solvents and compounds that improve the film thickness uniformity and surface smoothness when a liquid crystal aligning agent is applied, and compounds that improve the adhesion between the liquid crystal aligning film and the substrate.

  Specific examples of the solvent (poor solvent) that improves the uniformity of the film thickness and the 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, 1-hexanol, 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, 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- Low 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, lactate isoamyl ester Examples include solvents having surface tension.

  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 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 polymer 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-to Ethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltri Methoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-amino Propyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl 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-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetra Glycidyl-2,4-hexanediol, N, N, N ′, N ′,-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N Examples include ', N',-tetraglycidyl-4,4'-diaminodiphenylmethane.

  Further, in addition to improving the adhesion between the substrate and the film, the following phenoplast-based additive may be introduced into the liquid crystal aligning agent for the purpose of further preventing deterioration of electrical characteristics due to the backlight. Specific phenoplast additives are shown below, but are not limited to this structure.

  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 the polymer component contained in a liquid crystal aligning agent, and more. Preferably it is 1-20 mass parts. 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 liquid crystal orientation may be deteriorated.

  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.

<Liquid crystal alignment film and liquid crystal display element>
The liquid crystal aligning 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, light irradiation or the like, or without alignment treatment in vertical alignment applications. In this case, the substrate to be used is not particularly limited as long as it is a highly transparent substrate, and a glass substrate or a plastic substrate such as an acrylic substrate or a polycarbonate substrate can be used. In addition, it is preferable to use a substrate on which an ITO (Indium Tin Oxide) electrode or the like for driving a liquid crystal is formed from the viewpoint of simplifying the process. Further, in the reflection type liquid crystal display element, an opaque material such as a silicon wafer can be used as long as the substrate is only on one side, and in this case, a material that reflects light such as aluminum can be used.

  The application method of the liquid crystal aligning agent is not particularly limited, but industrially, a method of screen printing, offset printing, flexographic printing, ink jet, or the like is common. Other coating methods include dip, roll coater, slit coater, spinner and the like, and these may be used depending on the purpose. In this invention, it is estimated that it is isolate | separated into the layer of (A) component and the layer of (B) component in the step which apply | coated the liquid crystal aligning agent to the board | substrate.

  Firing after applying the liquid crystal aligning agent on the substrate can be performed at 50 to 300 ° C., preferably 80 to 250 ° C. by a heating means such as a hot plate, and the solvent can be evaporated to form a coating film. If the thickness of the coating film formed 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. Preferably it is 10-100 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 alignment film thus obtained is presumed to be separated into two layers, a layer derived from the component (A) and a layer derived from the component (B).

  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 twisted nematic (TN) method, a vertical alignment (VA) method, a horizontal alignment (IPS) method, an OCB alignment (OCB: OCB). There are various types such as Optically Compensated Bend).

  As a liquid crystal cell manufacturing method, a pair of substrates on which a liquid crystal alignment film is formed are prepared, spacers are scattered on the liquid crystal alignment film of one substrate, and the liquid crystal alignment film surface is on the inside, Examples include a method of bonding substrates and injecting liquid crystal under reduced pressure, or a method of sealing by bonding a substrate after dropping the liquid crystal on the liquid crystal alignment film surface on which spacers are dispersed. The thickness of the spacer at this time is preferably 1 to 30 μm, more preferably 2 to 10 μm.

  Examples of the liquid crystal include positive liquid crystal having positive dielectric anisotropy and negative liquid crystal having negative dielectric anisotropy, specifically, for example, MLC-2003, MLC-6608, MLC-6609 manufactured by Merck & Co., Inc. Etc. can be used.

  As described above, the liquid crystal display device manufactured using the liquid crystal aligning agent of the present invention has a high voltage holding ratio while maintaining the rubbing resistance, which has been a conventionally required characteristic, and is modern. As the strict requirements are satisfied, the charge accumulation becomes very small, and it can be suitably used for, for example, a mobile phone or a tablet terminal.

  Hereinafter, the present invention will be specifically described with reference to examples. However, it goes without saying that the present invention is not construed as being limited to these examples. In addition, the symbol used below and the measuring method of each characteristic are as follows.

(Tetracarboxylic dianhydride)
CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride TDA: 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride PPHT: N, N ′ -Bis (1,2-cyclohexanedicarboxylic anhydride-4-ylcarbonyl) -1,4-phenylenediamine

(Diamine)
DBA: 3,5-diaminobenzoic acid p-PDA: p-phenylenediamine DDM: 4,4′-diaminodiphenylmethane BAPU: 1,3-bis (4-aminophenethyl) urea APC16: 1,3-diamino-4- Hexadecyloxybenzene APC18: 1,3-diamino-4-octadecyloxybenzene DADPA: 4,4′-diaminodiphenylamine DA-5MG: 1,5-bis (4-aminophenoxy) pentane

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

(Additive)
LS-2450: 3-aminopropyldiethoxymethylsilane LS-3150: 3-aminopropyltriethoxysilane TM-BIP: 2,2′-bis [4-hydroxy-3,5-bis (hydroxymethyl) phenyl] propane LS-2450 and LS-3150 are trade names of Shin-Etsu Chemical Co., Ltd.

[Measurement of molecular weight of polymer]
The molecular weights of the polyimide and polyamic acid in the synthesis examples were measured with a GPC (room temperature gel permeation chromatography) apparatus, and the number average molecular weight (hereinafter also referred to as Mn) and the weight average molecular weight (hereinafter referred to as Mn) as polyethylene glycol and polyethylene oxide equivalent values. Mw.) Was calculated.
GPC device: manufactured by Shodex (GPC-101)
Column: manufactured by Shodex (series of KD803 and KD805)
Column temperature: 50 ° C
Eluent: N, N-dimethylformamide (as additives, 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 / standard sample for preparing a calibration curve: TSK standard polyethylene oxide (weight average molecular weight (Mw) of about 900,000, 150,000, 100,000, 30000) manufactured by Tosoh Corporation, and polyethylene glycol (peak top molecular weight manufactured by Polymer Laboratories) (Mp) about 12000, 4000, 1000). In order to avoid the overlapping of peaks, the measurement was performed separately on two samples: a sample in which 4 types of 900000, 100000, 12000, and 1000 were mixed and a sample in which 3 types of 150,000, 30000, and 4000 were mixed.

[Measurement of imidization rate]
The imidation ratio of polyimide was measured as follows. 20 mg of the polyimide powder was put into an NMR sample tube, and 0.53 mL of deuterated dimethyl sulfoxide (DMSO-d6, 0.05% TMS mixed product) was added and completely dissolved. 500 MHz proton NMR was measured for this solution with the NMR measuring device by the JEOL datum company (JNM-ECA500). The imidation rate is determined based on protons derived from structures that do not change before and after imidation as reference protons, and the peak integrated value of these protons and the proton peak derived from the NH group of polyamic acid appearing near 9.5 to 10.0 ppm. It calculated | required by following Formula using the integrated value.
Imidation ratio (%) = (1−α · x / y) × 100
In the above formula, x is the proton peak integrated value derived from the NH group of the polyamic acid, y is the peak integrated value of the reference proton, and α is one NH group proton of the polyamic acid in the case of the polyamic acid (imidation rate is 0%). The number ratio of the reference protons.

[Production of liquid crystal cell]
A liquid crystal aligning agent was spin-coated on a glass substrate with a transparent electrode, dried on a hot plate at a temperature of 80 ° C. for 60 seconds, and then fired in a nitrogen atmosphere using a 220 ° C. IR (infrared) oven for 20 minutes. A coating film having a thickness of 100 nm was formed. This coating film surface is rubbed with a rubbing apparatus having a roll diameter of 120 mm using a cotton cloth (YA-25C, manufactured by Yoshikawa) under the conditions of a roll rotation speed of 1000 rpm, a roll traveling speed of 50 mm / sec, and an indentation amount of 0.4 mm. A substrate with a film was obtained.

  Two substrates are prepared, a 4 μm spacer is sprayed on the surface of the liquid crystal alignment film, and a sealing agent (Sumitomo Chemical Co., Ltd. NX-1500T) is printed on it with a seal dispenser. After bonding the substrates so that the liquid crystal alignment film faces each other and the rubbing direction is perpendicular, the sealing agent is cured (temporary curing: 80 ° C. for 10 minutes, main curing: 150 ° C. for 1 hour 45 minutes) to form an empty cell. Produced. Liquid crystal MLC-2003 (Merck Japan Co., Ltd.) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain a twisted nematic liquid crystal cell. In addition, these operation was performed using each liquid crystal aligning agent obtained in Examples 1-8 and Comparative Examples 1-5.

[Evaluation of rubbing resistance]
At the stage of obtaining a substrate with a liquid crystal alignment film in [Production of liquid crystal cell], the surface of the liquid crystal alignment film was observed with a confocal laser microscope and visually, and evaluated according to the following criteria. The results are shown in Table 3.
○: Scraped and rubbing scratches are not observed either visually or with a laser microscope.
Δ: Scraping and rubbing scratches are not observed visually, but scraping and rubbing scratches are observed with a laser microscope.
X: A film | membrane peels or a rubbing damage | wound is observed also with a laser microscope and visual observation.

[Measurement of VHR (voltage holding ratio)]
A voltage of 4V is applied for 60 μs at a temperature of 60 ° C. to the twisted nematic liquid crystal cell manufactured by the method described in [Preparation of liquid crystal cell] above, and the voltage after 166.7 ms is measured. Whether it was made was calculated as a voltage holding ratio, and evaluated according to the following criteria. For measuring the voltage holding ratio, a VHR-1 voltage holding ratio measuring device manufactured by Toyo Corporation was used. The results are shown in Table 3.
A: Over 85% B: 80% to 85%
Δ: Less than 80%

[Measurement of volume resistivity]
Each composition [AL-1] to [AL-10] was filtered through a 0.2 μm filter, and then applied onto a glass substrate with an ITO transparent electrode by spin coating, and then on a hot plate at 80 ° C. for 1 minute. After drying, baking was performed at 220 ° C. for 20 minutes to form a film having a thickness of 220 nm. Aluminum is deposited on the surface of the coating film by a vacuum deposition method through a mask at a vacuum degree of 1.0 × 10 ⁻³ Pa and a deposition rate of 1 nm / s, and an upper electrode of 1.0 mmφ is formed to measure volume resistivity. A sample was prepared.
A voltage of 10 V is applied between the ITO electrode and the aluminum electrode of this sample, the current value 180 seconds after the voltage application is measured, and the volume resistivity is calculated from this value and the measured values of the electrode area and film thickness. did.
The resistance value was measured under the condition that an LED backlight was installed under the sample substrate. The apparatus used for the measurement was a 6517A ELECTROMETER manufactured by KEITHLEY, and measurement was performed in a nitrogen atmosphere using a shield box SM-1 with a positioner manufactured by MEASURE Jig. The results are shown in Table 4.

[Measurement of RDC (residual DC voltage)]
To the twisted nematic liquid crystal cell manufactured by the method described in [Preparation of liquid crystal cell], a DC voltage was applied from 0 V to 1.0 V at a temperature of 23 ° C., and the flicker amplitude at each voltage was applied. Measurement was performed using a level photoelectric conversion device, and a calibration curve was created at the flicker amplitude level and applied voltage. Ground the liquid crystal cell for 5 minutes and leave it alone. After applying the AC voltage to V50 (voltage that reduces the luminance) and the DC voltage of 5.0 V for 1 hour, measure the flicker amplitude level immediately after setting the DC voltage to 0 V only. The RDC was estimated by comparing with a calibration curve prepared in advance. This RDC estimation method is called a flicker reference method. Moreover, when RDC is small, it can be said that charge accumulation is small. The results are shown in Table 3.
◎: Less than 0.05 ○: 0.05 or more and less than 0.08 Δ: 0.08 or more and less than 0.20 ×: 0.20 or more

[Synthesis example]
The numerical value in parentheses described after the tetracarboxylic acid component and the diamine component represents the molar fraction of the raw material monomer at the time of polymer synthesis.

(Synthesis Example 1)
Polymerization of polyamic acid [PAA-1: TDA (50) CBDA (50) / DDM (100)] and preparation of composition [AL-1: TDA (50) CBDA (50) / DDM (100)] Nitrogen inlet tube In a 50 ml four-necked flask equipped with a mechanical stirrer, 2.78 g (14.01 mmol) of DDM was measured, 17.40 g of GBL was added and dissolved, cooled to about 10 ° C. under a nitrogen atmosphere, and TDA of 2.10 g. (6.99 mmol) was added little by little, and it was returned to room temperature and reacted for 2 hours. Thereafter, 1.26 g (6.42 mmol) of CBDA and 17.40 g of NMP were added, and the mixture was returned to room temperature and reacted for 4 hours to obtain a 15% by mass solution of polyamic acid [PAA-1]. The number average molecular weight of the obtained polyamic acid [PAA-1] was 15,200, and the weight average molecular weight was 47,500.

  In a 50 ml Erlenmeyer flask equipped with a stirrer, 15.02 g of the obtained 15% by mass polyamic acid [PAA-1] solution was weighed, and 16.89 g of GBL and 5.64 g of BCS were added, followed by 2 hours at room temperature. The mixture was stirred to obtain a composition [AL-1] having a solid content concentration of 6.0% by mass, GBL of 59% by mass, NMP of 20% by mass, and BCS of 15% by mass.

(Synthesis Example 2)
Preparation of composition [AL-2: TDA (50) CBDA (50) / DDM (100) + LS-3150 (1)] 15% by mass obtained in Synthesis Example 1 in a 50 ml Erlenmeyer flask equipped with a stirrer 14.12 g of a solution of polyamic acid [PAA-1] was weighed, and 0.42 g of a solution obtained by diluting GBL 15.56 g, BCS 5.56 g, and LS-3150 to 2% by mass with NMP was added, and the mixture was stirred at room temperature for 2 hours. Thus, a composition [AL-2] having a solid content concentration of 6.0% by mass, GBL of 59% by mass, NMP of 20% by mass, and BCS of 15% by mass was obtained.

(Synthesis Example 3)
Preparation of Composition [AL-3: TDA (50) CBDA (50) / DDM (100) + LS-3150 (1) + TM-BIP (1)] Obtained in Synthesis Example 1 in a 50 ml Erlenmeyer flask equipped with a stirrer 14.12 g of the obtained 15% by mass polyamic acid [PAA-1] solution was weighed, GBL 15.35 g, BCS 5.35 g, LS-3150 diluted to 5% by mass with NMP 0.42 g, TM -0.42 g of a solution obtained by diluting BIP to 5% by mass with NMP was added and stirred at room temperature for 2 hours. The solid content concentration was 6.0% by mass, GBL was 59% by mass, NMP was 20% by mass, and BCS was 15%. A mass% composition [AL-3] was obtained.

(Synthesis Example 4)
Polymerization and composition of polyamic acid [PAA-2: TDA (50) CBDA (50) / BAPU (20) DDM (80)] [AL-4: TDA (50) CBDA (50) / BAPU (20) DDM ( 80) + LS-3150 (1) + TM-BIP (1)] In a 50 ml four-necked flask equipped with a nitrogen inlet tube and a mechanical stirrer, 0.71 g (2.38 mmol) of BAPU and 1.90 g of DDM (9 .58 mmol), 20.18 g of GBL was added and dissolved, cooled to about 10 ° C. under a nitrogen atmosphere, 1.80 g (6.30 mmol) of TDA was added little by little, and the mixture was returned to room temperature and reacted for 2 hours. Thereafter, 1.08 g (5.44 mmol) of CBDA and 20.18 g of NMP were added, and the mixture was returned to room temperature and reacted for 4 hours to obtain a 12 mass% polyamic acid [PAA-2] solution. The number average molecular weight of the obtained polyamic acid [PAA-2] was 12,700, and the weight average molecular weight was 38,200.

  15.01 g of a 12% by weight polyamic acid [PAA-2] solution obtained in a 50 ml Erlenmeyer flask equipped with a stirrer was weighed, GBL 9.78 g, BCS 4.50 g, and LS-3150 were 5 NMP. 0.36 g of a solution diluted to 5% by mass and 0.36 g of a TM-BIP diluted to 5% by mass with NMP were added and stirred at room temperature for 2 hours. The solid content concentration was 6.0% by mass and GBL was 59% by mass. %, NMP 20 mass%, BCS 15 mass% composition [AL-4].

(Synthesis Example 5)
Polymerization and composition of polyamic acid [PAA-3: TDA (30) CBDA (70) / DDM (100)] [AL-5: TDA (30) CBDA (70) / DDM (100) + LS-3150 (1) Preparation of + TM-BIP (1)] In a 50 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 2.97 g (14.98 mmol) of DDM was measured, and 18.09 g of GBL was added and dissolved. The mixture was cooled to about 10 ° C., 1.35 g (4.50 mmol) of TDA was added little by little, and the mixture was returned to room temperature and reacted for 2 hours. Thereafter, 2.05 g (10.50 mmol) of CBDA and 18.09 g of NMP were added, and the mixture was returned to room temperature and reacted for 4 hours to obtain a 15% by mass polyamic acid [PAA-3] solution. The resulting polyamic acid [PAA-3] had a number average molecular weight of 11,000 and a weight average molecular weight of 41,000.

  A solution of 15% by mass of polyamic acid [PAA-3] obtained in a 50 ml Erlenmeyer flask equipped with a stir bar was weighed 15.00 g, and GBL 15.97 g, BCS 5.63 g, and LS-3150 were NMP 5 0.45 g of a solution diluted to 5% by mass and 0.45 g of a TM-BIP diluted to 5% by mass with NMP were added and stirred at room temperature for 2 hours. The solid content concentration was 6.0% by mass and GBL was 59% by mass. %, NMP 20% by mass, and BCS 15% by mass [AL-5].

(Synthesis Example 6)
Polymerization of polyamic acid [PAA-4: TDA (70) CBDA (30) / DDM (100)] and composition [AL-6: TDA (70) CBDA (30) / DDM (100) + LS-3150 (1) Preparation of + TM-BIP (1)] In a 50 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 2.97 g (14.98 mmol) of DDM was measured and 19.86 g of GBL was added and dissolved. The mixture was cooled to about 10 ° C., 3.15 g (10.48 mmol) of TDA was added little by little, and the mixture was returned to room temperature and reacted for 2 hours. Thereafter, 0.88 g (4.50 mmol) of CBDA and 19.86 g of NMP were added, and the mixture was returned to room temperature and reacted for 4 hours to obtain a 15% by mass polyamic acid [PAA-4] solution. The number average molecular weight of the obtained polyamic acid [PAA-4] was 14,500, and the weight average molecular weight was 45,100.

  A solution of 15% by mass of polyamic acid [PAA-4] obtained in a 50 ml Erlenmeyer flask equipped with a stirrer was weighed 15.00 g, and GBL 15.97 g, BCS 5.63 g, LS-3150 was NMP 5 0.45 g of a solution diluted to 5% by mass and 0.45 g of a TM-BIP diluted to 5% by mass with NMP were added and stirred at room temperature for 2 hours. The solid content concentration was 6.0% by mass and GBL was 59% by mass. %, NMP 20% by mass and BCS 15% by mass [AL-6].

(Synthesis Example 7)
Polymerization of polyamic acid [PAA-5: TDA (100) / p-PDA (90) APC18 (10)] In a 50 ml four-necked flask equipped with a nitrogen inlet tube and a mechanical stirrer, 9.00 g (0.030 mol) of TDA , 2.92 g (0.027 mol) of p-PDA and 1.13 g (0.0030 mol) of APC18 were reacted in NMP73.40 g at 50 ° C. for 24 hours to obtain polyamic acid [PAA-5]. A solution was obtained. The number average molecular weight of the obtained polyamic acid [PAA-5] was 15,800, and the weight average molecular weight was 49,200.

(Synthesis Example 8)
Preparation of polyimide [SPI-1: TDA (100) / p-PDA (90) APC18 (10)] A solution of polyamic acid [PAA-5] obtained in Synthesis Example 7 was added to a 100 ml Erlenmeyer flask equipped with a stirrer. 20.00 g, NMP 30.67 g, acetic anhydride 7.16 g and pyridine 3.32 g were added, and the mixture was stirred at room temperature for 30 minutes and then stirred at 40 ° C. for 3 hours for reaction. After completion of the reaction, the polymer (polyimide) was slowly poured into 214 g of methanol, and stirred for 30 minutes, and then the solid was collected by filtration. The obtained solid was sufficiently washed with methanol and then vacuum-dried at 100 ° C. to obtain a polyimide powder. The imidation ratio of the obtained polyimide [SPI-1] was 85%.

  29.00 g of GBL was added to 2.60 g of the obtained polyimide powder, stirred and dissolved at 50 ° C. for 24 hours, and confirmed to be completely dissolved, 4.00 g of GBL, 2% by mass of LS-2450 6.15 g of GBL solution was added and stirred at 50 ° C. for 24 minutes to obtain a polyimide solution [SPI-1a] having a solid content concentration of 6.0% by mass and GBL of 94% by mass.

(Synthesis Example 9)
Polymerization of polyamic acid [PAA-6: TDA / BAPU (30) p-PDA (60) APC18] In a 50 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 9.31 g (0.031 mol) of TDA, BAPU 2.77 g (0.0093 mol) of p-PDA, 2.01 g (0.019 mol) of p-PDA and 1.17 g (0.0031 mol) of APC18 were allowed to react at 50 ° C. for 24 hours in 86.38 g of NMP. A solution of polyamic acid [PAA-6] was obtained. The number average molecular weight of the obtained polyamic acid [PAA-6] was 10,500, and the weight average molecular weight was 35,900.

(Synthesis Example 10)
Preparation of Polyimide [SPI-2: TDA / BAPU (30) p-PDA (60) APC18] In a 100 ml Erlenmeyer flask equipped with a stirrer, a solution of polyamic acid [PAA-6] obtained in Synthesis Example 9 was added. 0.000 g, NMP (50.50 g), acetic anhydride (10.01 g) and pyridine (4.65 g) were added, and the mixture was stirred at room temperature for 30 minutes, and then stirred at 40 ° C. for 3 hours for reaction. After completion of the reaction, the polymer was slowly poured into 580 g of methanol to precipitate the polymer, stirred for 30 minutes, and then the solid was collected by filtration. The obtained solid was sufficiently washed with methanol and then vacuum-dried at 100 ° C. to obtain a polyimide powder. The imidation ratio of the obtained polyimide [SPI-2] was 82%.

  Add 30.59 g of GBL to 2.66 g of the obtained polyimide powder, stir and dissolve at 50 ° C. for 24 hours, confirm that it is completely dissolved, 6.55 g of GBL, 2% by mass of LS-2450 6.83 g of GBL solution was added and stirred at 50 ° C. for 24 minutes to obtain a polyimide solution [SPI-2a] having a solid content concentration of 6.0% by mass and GBL of 94% by mass.

(Synthesis Example 11)
Polymerization of polyamic acid [PAA-7: TDA (100) / p-PDA (90) APC16 (10)] 7.51 g (0.025 mol) of TDA in a 50 ml four-necked flask equipped with a nitrogen inlet tube and a mechanical stirrer , P-PDA 2.43 g (0.023 mol) and APC16 0.87 g (0.0025 mol) were reacted in NMP 61.26 g at 50 ° C. for 24 hours to obtain a solution of polyamic acid [PAA-7] Got. The number average molecular weight of the obtained polyamic acid [PAA-7] was 13,600, and the weight average molecular weight was 50,200.

(Synthesis Example 12)
Preparation of polyimide [SPI-3: TDA (100) / p-PDA (90) APC16 (10)] A solution of polyamic acid [PAA-7] obtained in Synthesis Example 11 was added to a 100 ml Erlenmeyer flask equipped with a stirrer. 20.00 g, NMP 30.67 g, acetic anhydride 7.18 g, and pyridine 3.33 g were added, and the mixture was stirred at room temperature for 30 minutes, and then stirred at 40 ° C. for 3 hours for reaction. After completion of the reaction, the polymer was slowly poured into 214 g of methanol to precipitate a polymer, stirred for 30 minutes, and then a solid was collected by filtration. The obtained solid was sufficiently washed with methanol and then vacuum dried at 100 ° C. to obtain a polyimide powder. The imidation ratio of the obtained polyimide [SPI-3] was 88%.

  29.90 g of GBL was added to 2.60 g of the obtained polyimide powder, stirred and dissolved at 50 ° C. for 24 hours, and confirmed to be completely dissolved, 4.00 g of GBL, 2% by mass of LS-2450 6.15 g of the GBL solution was added and stirred at 50 ° C. for 24 minutes to obtain a polyimide solution [SPI-3a] having 6.0% by mass and 94% by mass of GBL.

(Comparative Synthesis Example 1)
Polymerization of polyamic acid [PAA-8: PPHT (90) CBDA (10) / p-PDA (90) APC18 (10)] In a 50 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 2.44 g of PPHT was obtained. The reaction was carried out in 0.12 g of CBDA, 0.58 g of p-PDA, 0.26 g of APC18, and 19.11 g of NMP for 4 hours to obtain a solution of polyamic acid [PAA-8]. The number average molecular weight of the obtained polyamic acid [PAA-8] was 13,000, and the weight average molecular weight was 45,000.

(Comparative Synthesis Example 2)
Preparation of polyimide [SPI-4: PPHT (90) CBDA (10) / p-PDA (90) APC18 (10)] In a 100 ml Erlenmeyer flask equipped with a stir bar, polyamic acid [PAA obtained in Comparative Synthesis Example 1] -8] was added, 22.37 g of NMP, 33.72 g of NMP, 5.96 g of acetic anhydride and 2.77 g of pyridine were added, and the mixture was stirred at room temperature for 30 minutes and then stirred at 70 ° C. for 3 hours for reaction. After completion of the reaction, the polymer was slowly poured into 250 g of methanol to precipitate a polymer, stirred for 30 minutes, and then a solid was collected by filtration. The obtained solid was sufficiently washed with methanol and then vacuum dried at 100 ° C. to obtain a polyimide powder. The imidation ratio of the obtained polyimide [SPI-4] was 88%.

  33.00 g of GBL was added to 2.60 g of the obtained polyimide powder, stirred and dissolved at 50 ° C. for 24 hours, and confirmed to be completely dissolved. The solid concentration was 6.0% by mass and GBL was 94 A mass% polyimide solution [SPI-4a] was obtained.

(Comparative Synthesis Example 3)
Polymerization and composition of polyamic acid [PAA-9: TDA (50) CBDA (50) / DDM (20) p-PDA (80)] [AL-7: TDA (50) CBDA (50) / DDM (20) Preparation of p-PDA (80) + LS-3150 (1)] In a 100 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 1.58 g (8.00 mmol) of DDM and 3.46 g of p-PDA (32 1.00 mmol), and 41.32 g of GBL was added and dissolved, cooled to about 10 ° C. under a nitrogen atmosphere, 6.00 g (20.00 mmol) of TDA was added little by little, and the mixture was returned to room temperature and reacted for 2 hours. Thereafter, 3.52 g (18.00 mmol) of CBDA and 41.32 g of NMP were added, and the mixture was returned to room temperature and reacted for 4 hours to obtain a 15% by mass polyamic acid [PAA-9] solution. The number average molecular weight of the obtained polyamic acid [PAA-9] was 7,100, and the weight average molecular weight was 15,000.

  GBL 97.2 g, BCS 48.6 g, and LS-3150 0.15 g were added to the obtained 15% by mass polyamic acid [PAA-9] solution, and the mixture was stirred at room temperature for 2 hours. A composition [AL-7] having 0 mass%, GBL 59 mass%, NMP 20 mass%, and BCS 15 mass% was obtained.

(Comparative Synthesis Example 4)
Polymerization and composition of polyamic acid [PAA-10: TDA (70) CBDA (30) / DDM (20) p-PDA (80)] [AL-8: TDA (70) CBDA (30) / DDM (20) Preparation of p-PDA (80) + LS-3150 (1)] In a 100 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 1.58 g (8.00 mmol) of DDM and 3.46 g of p-PDA (32 (.00 mmol), 43.46 g of GBL was added and dissolved, cooled to about 10 ° C. under a nitrogen atmosphere, 8.40 g (28.00 mmol) of TDA was added little by little, and the mixture was returned to room temperature and reacted for 2 hours. Thereafter, 1.88 g (9.60 mmol) of CBDA and 43.46 g of NMP were added, and the mixture was returned to room temperature and reacted for 4 hours to obtain a 15 mass% polyamic acid [PAA-10] solution. The number average molecular weight of the obtained polyamic acid [PAA-10] solution was 7,100, and the weight average molecular weight was 15,000.

  To the obtained polyamic acid [PAA-10] solution, 97.2 g of GBL, 48.6 g of BCS, 0.15 g of LS-3150 were added, and the mixture was stirred at room temperature for 2 hours. The solid content concentration was 6.0% by mass, A composition [AL-8] having 59% by mass of GBL, 20% by mass of NMP and 15% by mass of BCS was obtained.

(Comparative Synthesis Example 5)
Polymerization and composition of polyamic acid [PAA-11: TDA (50) CBDA (50) / DBA (30) DDM (70)] [AL-9: TDA (50) CBDA (50) / DBA (30) DDM ( 70) + LS-3150 (1) + TM-BIP (1)] In a 100 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 2.08 g (10.50 mmol) of DDM and 0.68 g of DBA (4 Then, 18.06 g of GBL was added and dissolved, cooled to about 10 ° C. under a nitrogen atmosphere, 2.25 g (7.5 mmol) of TDA was added little by little, and the mixture was returned to room temperature and reacted for 2 hours. Thereafter, 1.35 g (6.90 mmol) of CBDA and 18.06 g of NMP were added, and the mixture was returned to room temperature and reacted for 4 hours to obtain a 15% by mass solution of polyamic acid [PAA-11]. The number average molecular weight of the obtained polyamic acid [PAA-11] was 9,400, and the weight average molecular weight was 25,900.

  A solution of polyamic acid [PAA-11] obtained in a 50 ml Erlenmeyer flask equipped with a stir bar was measured at 15.05 g, and GBL 16.02 g, BCS 5.64 g, and LS-3150 were diluted to 5% by mass with NMP. 0.45 g of the obtained solution and 0.45 g of TM-BIP diluted to 5% by mass with NMP were added and stirred at room temperature for 2 hours. The solid content concentration was 6.0% by mass, GBL was 59% by mass, and NMP was A composition [AL-9] having 20% by mass and BCS of 15% by mass was obtained.

(Comparative Synthesis Example 6)
Polymerization of polyamic acid [PAA-12: TDA (20) CBDA (80) / DADPA (80) DDM (20)] and composition [AL-10: TDA (20) CBDA (80) / DADPA (80) DDM ( 20)] In a 100 ml four-necked flask equipped with a nitrogen introduction tube and a mechanical stirrer, 2.39 g (12.00 mmol) of DADPA and 0.59 g (3.00 mmol) of DDM were measured, and 55.37 g of NMP was added. The mixture was dissolved and cooled to about 10 ° C. under a nitrogen atmosphere, 0.90 g (3.0 mmol) of TDA and 2.26 g (11.55 mmol) of CBDA were added little by little, the mixture was returned to room temperature, reacted for 4 hours, and polyamic acid [ PAA-12] solution was obtained.

  In a 200 ml Erlenmeyer flask equipped with a stirrer, 61.01 g of the obtained polyamic acid [PAA-12] solution was weighed, 24.60 g of BCS and 36.91 g of NMP were added, and the mixture was stirred at room temperature for 2 hours. A composition [AL-10] having a partial concentration of 5.0% by mass, NMP of 75% by mass, and BCS of 20% by mass was obtained.

(Comparative Synthesis Example 7)
Polymerization of polyamic acid [PAA-13: TDA (100) / DA-5MG (100)] and preparation of polyimide [SPI-5: TDA (100) / DA-5MG (100)] A nitrogen introduction tube and a mechanical stirrer are provided. In another 100 ml four-necked flask, DA-5MG 3.72 g and TDA 3.70 g were reacted in 66.88 g of NMP for 4 hours to obtain a solution of polyamic acid [PAA-13].

  To a 200 ml Erlenmeyer flask equipped with a stirrer, 74.31 g of the obtained polyamic acid [PAA-13] solution, 72.31 g of NMP, 15.48 g of acetic anhydride, and 7.19 g of pyridine were added, and 30 at room temperature. The mixture was stirred for 3 minutes and then reacted at 40 ° C. for 3 hours. After completion of the reaction, the polymer was slowly poured into 500 g of methanol, and the polymer was stirred. After stirring for 30 minutes, the solid was collected by filtration. The obtained solid was sufficiently washed with methanol and then vacuum dried at 100 ° C. to obtain a polyimide ([SPI-5]) powder.

  80.00 g of GBL and 15.00 g of BCS were added to 5.00 g of the obtained polyimide powder, and the mixture was stirred at 50 ° C. for 6 hours. The solid content concentration was 5.0 mass%, NMP was 80 mass%, and BCS was 15 mass. % Polyimide solution [SPI-5a] was obtained.

(Example 1) [AL-1]: [SPI-1a] = 80: 20
[AL-1] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

(Example 2) [AL-2]: [SPI-1a] = 80: 20
[AL-2] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

(Example 3) [AL-3]: [SPI-1a] = 80: 20
[AL-3] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

(Example 4) [AL-3]: [SPI-2a] = 80: 20
[AL-3] and [SPI-2a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

(Example 5) [AL-5]: [SPI-1a] = 80: 20
[AL-5] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

(Example 6) [AL-6]: [SPI-1a] = 80: 20
[AL-6] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

(Example 7) [AL-3]: [SPI-3a] = 80: 20
[AL-3] and [SPI-3a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

(Example 8) [AL-4]: [SPI-1a] = 80: 20
[AL-4] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

Comparative Example 1 [AL-9]: [SPI-1a] = 80: 20
[AL-9] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

Comparative Example 2 [AL-3]: [SPI-4a] = 80: 20
[AL-3] and [SPI-4a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

Comparative Example 3 [AL-7]: [SPI-1a] = 80: 20
[AL-7] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

Comparative Example 4 [AL-8]: [SPI-1a] = 80: 20
[AL-8] and [SPI-1a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

Comparative Example 5 [AL-10]: [SPI-5a] = 80: 20
[AL-10] and [SPI-5a] were mixed at a mass ratio of 80:20 and stirred at room temperature for 2 hours to obtain a liquid crystal aligning agent.

As shown in Table 3, a polymer obtained by reacting a tetracarboxylic acid component containing TDA with a diamine component containing a diamine having a side chain represented by the above formula (1), and a tetracarboxylic acid containing TDA Examples 1 to 8, which are liquid crystal aligning agents each having a polymer obtained by reacting an acid component with a diamine component consisting only of a diamine having —CR ²¹ ₂ — in the main chain, are both VHR and rubbing resistant. The RDC was also very low.

On the other hand, Comparative Example 2 using a polymer not using TDA as a raw material, and Comparative Examples 1 and 3 using a polymer containing a diamine in which the diamine component of the raw material does not have —CR ²¹ ₂ — in the main chain as component (B). 4 and 4 and Comparative Example 5 in which the diamine having the side chain represented by the formula (1) was not used as the component (A), RDC was significantly larger than those in Examples 1-8. In addition, from Table 4, compositions [AL-7] to [AL-10] using a polymer including a diamine having no —CR ²¹ ₂ — in the main chain have a low volume resistivity. In Comparative Examples 1 and 3 to 5 using [AL-7] to [AL-10] as the component (B), it is estimated that RDC was large.

Claims (5)

The liquid crystal aligning agent characterized by containing the following (A) component and the following (B) component.
(A) component: at least one polymer selected from a polyimide precursor obtained by polymerizing a tetracarboxylic acid component and a diamine component and a polyimide obtained by imidizing this polyimide precursor, The tetracarboxylic acid component is 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1- It contains at least one selected from naphthalene succinic acid diester and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid diester dichloride, and the diamine component is represented by the following formula (1): Polymer comprising a diamine having a side chain represented

(In Formula (1), P ¹ represents a single bond or a divalent organic group, Q ¹ , Q ² , and Q ³ each independently represent a divalent benzene ring or a cyclohexane ring, and p, q, r Each independently represents an integer of 0 or 1, and P ² represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or a divalent organic group having 12 to 25 carbon atoms having a steroid skeleton.)
(B) component: at least one polymer selected from a polyimide precursor obtained by polymerizing a tetracarboxylic acid component and a diamine component and a polyimide obtained by imidizing this polyimide precursor, The tetracarboxylic acid component is 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1- It contains at least one selected from naphthalene succinic acid diester and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic acid diester dichloride, and the diamine component is -CR ^{21 in the} main chain. ₂ - group (wherein two ^{R 21} each independently represent a hydrogen atom or an organic group, two ^{R 21} are one May form a cyclic structure consisting thing.) Consisting only of a diamine having a polymer 2. The liquid crystal aligning agent according to claim 1, wherein in the component (B), the diamine component comprises only a diamine represented by the following formula (2).

(In formula (2), two X's each independently represent an oxygen atom or a single bond, n represents an integer of 1 to 10, and two R ^22's each independently represent a hydrogen atom or an alkyl having 1 to 5 carbon atoms. A cyclic structure may be formed by representing a group, a fluoroalkyl group having 1 to 5 carbon atoms, or a fluorine atom, or by combining two R ^22s together to form alkylene having 2 to 7 carbon atoms. ) The liquid crystal aligning agent according to claim 1 or 2, wherein in the component (A), the diamine having a side chain represented by the formula (1) is a diamine represented by the following formula (3).

(In Formula (3), P ¹ represents a single bond or a divalent organic group, Q ¹ , Q ² , and Q ³ each independently represent a divalent benzene ring or a cyclohexane ring, and p, q, r Each independently represents an integer of 0 or 1, and P ² represents a hydrogen atom, an alkyl group having 1 to 22 carbon atoms, or a divalent organic group having 12 to 25 carbon atoms having a steroid skeleton.)   A liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to any one of claims 1 to 3 to a substrate and baking it.   A liquid crystal display element comprising the liquid crystal alignment film according to claim 4.