JP6617878B2 - Liquid crystal alignment treatment agent and liquid crystal display element using the same - Google Patents

Description

  The present invention relates to a liquid crystal alignment treatment agent used in the production of a liquid crystal display element, a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent, and a liquid crystal display element using the liquid crystal alignment film.

  In recent years, liquid crystal display elements have become widely used in large-screen liquid crystal televisions and high-definition mobile applications (display parts of digital cameras and mobile phones). The unevenness of the step of the substrate is getting larger. Even in such a situation, it has been demanded that the liquid crystal alignment film is uniformly coated on a large substrate or a step from the viewpoint of display characteristics. When the liquid crystal alignment treatment agent (also referred to as coating solution) of polyamic acid or solvent-soluble polyimide (also referred to as soluble polyimide), which is a polyimide precursor, is applied to a substrate in the process of preparing the liquid crystal alignment film, it is industrially flexographic. In general, it is performed by a printing method or an ink jet coating method. At that time, in addition to N-methyl-2-pyrrolidone and γ-butyrolactone, which are solvents having excellent resin solubility (also referred to as good solvents), the coating solution has a coating film uniformity of the liquid crystal alignment film. In order to increase this, butyl cellosolve, which is a solvent having low resin solubility (also referred to as a poor solvent), or the like is mixed (see, for example, Patent Document 1).

JP-A-2-37324

  The liquid crystal alignment film is required to have functions for controlling the alignment state of the liquid crystal (also referred to as liquid crystal alignment) and for electrical characteristics such as reliability and image sticking characteristics in the liquid crystal display element. On the other hand, using a liquid crystal alignment treatment agent in which a polymer of polyamic acid or soluble polyimide having liquid crystal alignment characteristics and a polymer having electric characteristics is mixed is used as a method for enhancing the characteristics. Yes.

  However, in these polymers, there are many cases where the solvent solubility of the polymer is different or the polarity of the polymer is different. Accordingly, in the liquid crystal aligning agent containing these polymers, the polymer component is likely to precipitate while the liquid crystal aligning agent is being stored. Thus, when precipitation of a polymer component occurs, when the liquid-crystal aligning agent is apply | coated to a board | substrate, it exists in the tendency for the coating-film uniformity of a liquid crystal aligning film to fall. That is, the deposited polymer component generates repellency and pinholes, and when the liquid crystal display element is formed, the portion becomes a display defect. Even when the storage stability of the liquid crystal aligning agent is excellent, the polymer component may aggregate (also referred to as whitening / aggregation) on the substrate when the liquid crystal aligning agent is applied on the substrate. When this whitening / aggregation occurs, the coating film uniformity of the liquid crystal alignment film decreases as described above, and a uniform coating property cannot be obtained, resulting in a display defect in the liquid crystal display element.

  In recent years, a liquid crystal display element using a backlight with a large amount of light irradiation, such as a car navigation system or a large television, may be used or left in an environment exposed to light irradiation for a long time. is there. Even under such severe conditions, high stability is required for the voltage holding ratio which is one of the electrical characteristics of the liquid crystal display element. That is, if the voltage holding ratio is reduced by light irradiation from the backlight, a burn-in defect (also referred to as line burn-in), which is one of display defects of the liquid crystal display element, is likely to occur. A high liquid crystal display element cannot be obtained. Therefore, in the liquid crystal alignment film, in addition to good initial characteristics, for example, it is required that the voltage holding ratio does not easily decrease even after being exposed to light irradiation for a long time.

  Then, this invention aims at providing the liquid-crystal aligning agent which has the said characteristic. That is, the object of the present invention is to provide a liquid crystal alignment treatment agent containing two or more different polymers, which has excellent storage stability of the liquid crystal alignment treatment agent, and when the liquid crystal alignment treatment agent is applied on a substrate, It aims at providing the liquid crystal aligning film which suppressed the whitening and aggregation of a polymer component, and was excellent in the coating-film uniformity. In addition, an object is to provide a liquid crystal alignment film that can suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time in addition to good initial characteristics.

  Another object of the present invention is to provide a liquid crystal display device having the liquid crystal alignment film.

  Furthermore, an object of this invention is to provide the liquid-crystal aligning agent which can provide the said liquid crystal aligning film.

  As a result of intensive studies, the present inventor has found that a liquid crystal alignment treatment agent having two polymers having a specific structure is extremely effective for achieving the above object, and completes the present invention. It came.

That is, the present invention has the following gist.
(1) Liquid crystal aligning agent containing the following (A) component and (B) component.
(A) Component: A polymer containing at least one selected from a polyimide precursor having a structure having a nitrogen atom and a polyimide.
(B) Component: A polymer containing at least one selected from a polyimide precursor having a structure represented by the following formula [2] and a polyimide.

（式［２］中、Ｙ^１およびＹ^７はそれぞれ独立して、単結合、炭素数１〜１０のアルキレン基、−Ｏ−、−Ｎ（Ｒ^１）−（Ｒ^１は水素原子または炭素数１〜３のアルキル基を示す）、−ＣＯＮ（Ｒ^２）−（Ｒ^２は水素原子または炭素数１〜３のアルキル基を示す）、−Ｎ（Ｒ^３）ＣＯ−（Ｒ^３は水素原子または炭素数１〜３のアルキル基を示す）、−ＣＨ_２Ｏ−、−ＣＯＯ−および−ＯＣＯ−から選ばれる少なくとも１種の有機基を示し、Ｙ^２およびＹ^６はそれぞれ独立して、炭素数１〜１０のアルキレン基を示し、Ｙ^３およびＹ^５はそれぞれ独立して、水素原子または炭素数１〜１０のアルキル基を示し、Ｙ^４は酸素原子または硫黄原子を示す）。

(Wherein [2], ^{Y 1} and ^{Y 7} are each independently a single bond, an alkylene group having 1 to 10 carbon ^{atoms, -O -, - N (R} 1) - (R 1 is a hydrogen atom or a carbon atoms 1 to 3 alkyl groups ), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom) Or an alkyl group having 1 to 3 carbon atoms), at least one organic group selected from —CH ₂ O—, —COO— and —OCO—, wherein Y ² and Y ⁶ are each independently carbon An alkylene group having 1 to 10 carbon atoms, Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and Y ⁴ represents an oxygen atom or a sulfur atom).

(2) The liquid crystal alignment according to (1), wherein the structure having a nitrogen atom in the component (A) is at least one structure selected from the structures represented by the following formulas [1a] to [1c]. Processing agent.

（式［１ａ］中、Ｘ^１はベンゼン環または窒素含有芳香族複素環を示し、Ｘ^２は水素原子または炭素数１〜１２の脂肪族基で置換されたジ置換アミノ基を示し、式［１ｂ］中、Ｘ^３およびＸ^７はそれぞれ独立して、炭素原子を６〜１５個有し、かつベンゼン環を１〜２個有する芳香族基を示し、Ｘ^４およびＸ^６はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示し、Ｘ^５は炭素数２〜５のアルキレン基またはビフェニル基を示し、ｍは０または１の整数を示し、式［１ｃ］中、Ｘ^８およびＸ^１０はそれぞれ独立して、下記の式［１ｃ−ａ］および式［１ｃ−ｂ］で示される構造から選ばれる少なくとも１種の構造を示し、Ｘ^９は炭素数１〜１０のアルキレン基またはベンゼン環を示す）。

(In Formula [1a], X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring, X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms; 1b], X ³ and X ⁷ are each independently an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings, and X ⁴ and X ⁶ are each independently , A hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X ⁵ represents an alkylene group or biphenyl group having 2 to ⁵ carbon atoms, m represents an integer of 0 or 1, and in formula [1c], X ⁸ And X ¹⁰ each independently represents at least one structure selected from the structures represented by the following formulas [1c-a] and [1c-b], and X ⁹ represents an alkylene group having 1 to 10 carbon atoms. Or a benzene ring).

(3) In the above (1) or (2), the polymer of the component (A) is a polymer obtained by using a diamine compound represented by the following formula [1-1] as a part of the raw material. The liquid crystal aligning agent of description.

（式［１−１］中、Ｘ^Ａは前記式［１ａ］〜式［１ｃ］で示される構造から選ばれる少なくとも１種の構造を有する炭素数５〜５０の有機基を示し、Ａ^１およびＡ^２はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示す）。

(In Formula [1-1], X ^A represents an organic group having 5 to 50 carbon atoms having at least one structure selected from the structures represented by Formula [1a] to Formula [1c], and A ¹ and A ² each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(4) The liquid crystal according to (3), wherein the diamine compound is a polymer obtained by using a diamine compound represented by the following formulas [1a-1] to [1c-1] as a part of a raw material. Alignment treatment agent.

（式［１ａ−１］中、Ｘ^１はベンゼン環または窒素含有芳香族複素環を示し、Ｘ^２は水素原子または炭素数１〜１２の脂肪族基で置換されたジ置換アミノ基を示し、式［１ｂ−１］中、Ｘ^３およびＸ^７はそれぞれ独立して、炭素原子を６〜１５個有し、かつベンゼン環を１〜２個有する芳香族基を示し、Ｘ^４およびＸ^６はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示し、Ｘ^５は炭素数２〜５のアルキレン基またはビフェニル基を示し、ｍは０または１の整数を示し、式［１ｃ−１］中、Ｘ^８およびＸ^１０はそれぞれ独立して、前記式［１ｃ−ａ］および式［１ｃ−ｂ］で示される構造から選ばれる少なくとも１種の構造を示し、Ｘ^９は炭素数１〜５のアルキレン基またはベンゼン環を示し、式［１ａ−１］〜式［１ｃ−１］中、Ａ^１〜Ａ^６はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示す）。

(In the formula [1a-1], X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring, X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms, In formula [1b-1], X ³ and X ⁷ each independently represent an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings, and X ⁴ and X ⁶ are Each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X ⁵ represents an alkylene group or biphenyl group having 2 to ⁵ carbon atoms, m represents an integer of 0 or 1, and the formula [1c- 1], X ⁸ and X ¹⁰ each independently represent at least one structure selected from the structures represented by the formulas [1c-a] and [1c-b], and X ⁹ has 1 carbon atom. To an alkylene group or a benzene ring, represented by formulas [1a-1] to [ 1c-1], A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

(5) The liquid-crystal aligning agent as described in said (4) whose said diamine compound is at least 1 sort (s) of diamine compound chosen from the diamine compound shown by the following formula [1-1a]-a formula [1-4a]. .

（式［１−３ａ］中、Ｒ^１は水素原子または炭素数１〜５のアルキル基を示し、式［１−４ａ］中、ｎは１〜１０の整数を示し、式［１−１ａ］〜式［１−４ａ］中、Ａ^１〜Ａ^８はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示す）。

(In the formula [1-3a], R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. In the formula [1-4a], n represents an integer of 1 to 10, and the formula [1-1a] In Formula [1-4a], A ^{1 to} A ⁸ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

(6) The above-mentioned (1) to (5), wherein the polymer of the component (B) is a polymer obtained by using a diamine compound represented by the following formula [2-1] as a part of the raw material. The liquid-crystal aligning agent in any one.

（式［２−１］中、Ｙ^Ａは前記式［２］で示される構造を有する有機基を示し、Ａ^１およびＡ^２はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示す）。

(In Formula [2-1], Y ^A represents an organic group having the structure represented by Formula [2], and A ¹ and A ² are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Showing).

(7) The liquid-crystal aligning agent as described in said (6) whose said diamine compound is a polymer obtained by using the diamine compound shown by following formula [2a] for some raw materials.

（式［２ａ］中、Ｙ^１およびＹ^７はそれぞれ独立して、単結合、炭素数１〜１０のアルキレン基、−Ｏ−、−Ｎ（Ｒ^１）−（Ｒ^１は水素原子または炭素数１〜３のアルキル基を示す）、−ＣＯＮ（Ｒ^２）−（Ｒ^２は水素原子または炭素数１〜３のアルキル基を示す）、−Ｎ（Ｒ^３）ＣＯ−（Ｒ^３は水素原子または炭素数１〜３のアルキル基を示す）、−ＣＨ_２Ｏ−、−ＣＯＯ−および−ＯＣＯ−から選ばれる少なくとも１種の有機基を示し、Ｙ^２およびＹ^６はそれぞれ独立して、炭素数１〜１０のアルキレン基を示し、Ｙ^３およびＹ^５はそれぞれ独立して、水素原子または炭素数１〜１０のアルキル基を示し、Ｙ^４は酸素原子または硫黄原子を示し、Ａ^１およびＡ^２はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示す）。

(In Formula [2a], Y ¹ and Y ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —N (R ¹ ) — (R ¹ is a hydrogen atom or a carbon number, 1 to 3 alkyl groups ), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom) Or an alkyl group having 1 to 3 carbon atoms), at least one organic group selected from —CH ₂ O—, —COO— and —OCO—, wherein Y ² and Y ⁶ are each independently carbon an alkylene group having 1 to 10, ^{Y 3} and ^{Y 5} each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, ^{Y 4} represents an oxygen atom or a sulfur atom, ^{a 1} and a ² each independently represent a hydrogen atom or alkyl of 1 to 5 carbon atoms A group).

(8) The liquid crystal aligning agent according to (7), wherein the diamine compound is at least one diamine compound selected from diamine compounds represented by the following formulas [2-1a] to [2-3a]. .

（式［２−１ａ］〜式［２−３ａ］中、Ａ^１〜Ａ^６はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示す）。

(In the formulas [2-1a] to [2-3a], A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

(9) The polymer of the component (A) and the polymer of the component (B) are at least one selected from a polyimide precursor and a polyimide obtained by using a tetracarboxylic acid component represented by the following formula [3] The liquid crystal aligning agent according to any one of (1) to (8) above, which is a polymer of

（式［３］中、Ｚは下記の式［３ａ］〜式［３ｋ］で示される構造から選ばれる少なくとも１種の構造を示す）。

(In formula [3], Z represents at least one structure selected from structures represented by formula [3a] to formula [3k] below).

（式［３ａ］中、Ｚ^１〜Ｚ^４は水素原子、メチル基、エチル基、プロピル基、塩素原子またはベンゼン環を示し、それぞれ同じであっても異なってもよく、式［３ｇ］中、Ｚ^５およびＺ^６は水素原子またはメチル基を示し、それぞれ同じであっても異なってもよい）。

(In the formula [3a], Z ^{1 to} Z ⁴ represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring, which may be the same or different, and in the formula [3g] Z ⁵ and Z ⁶ each represent a hydrogen atom or a methyl group, and may be the same or different.

(10) The tetracarboxylic acid component is a tetracarboxylic acid having at least one structure selected from the structures represented by the formula [3a] and the formulas [3e] to [3g], wherein Z in the formula [3] The liquid-crystal aligning agent as described in said (9) which is a component.

(11) In the polymer of the component (A), the diamine compound represented by the formula [1a-1] to the formula [1c-1] is 5 mol% to 95 mol% in 100 mol% of all diamine components. The liquid crystal aligning agent according to any one of (4) to (10) above.

(12) In the polymer of the component (B), the diamine compound represented by the formula [2a] is 5 mol% to 95 mol% in 100 mol% of all diamine components. The liquid crystal aligning agent in any one of 11).

(13) Any of (1) to (12) above, wherein the polymer of component (B) is 0.5 to 950 parts by mass with respect to 100 parts by mass of polymer of component (A). A liquid crystal alignment treatment agent according to claim 1.

(14) The above (1) to (13) containing at least one solvent selected from N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone and γ-butyrolactone as a solvent for the liquid crystal aligning agent. The liquid-crystal aligning agent in any one of.

(15) As a solvent for the liquid crystal aligning agent, at least selected from 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether and dipropylene glycol dimethyl ether The liquid-crystal aligning agent in any one of said (1)-(14) containing 1 type of solvent.

(16) In the liquid crystal aligning agent, at least one substitution selected from the group consisting of a crosslinkable compound having an epoxy group, an isocyanate group, an oxetane group or a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group or a lower alkoxyalkyl group The liquid crystal aligning agent according to any one of (1) to (15) above, comprising at least one crosslinkable compound selected from a crosslinkable compound having a group and a crosslinkable compound having a polymerizable unsaturated bond.

(17) A liquid crystal alignment film obtained from the liquid crystal alignment treatment agent according to any one of (1) to (16).

(18) A liquid crystal alignment film obtained by an inkjet method using the liquid crystal aligning agent according to any one of (1) to (16).

(19) A liquid crystal display device having the liquid crystal alignment film according to (17) or (18).

  The liquid crystal aligning agent containing at least one polymer selected from the polyimide precursor or polyimide having a specific structure of the present invention is excellent in storage stability of the liquid crystal aligning agent, and the liquid crystal aligning agent is used as a substrate. When applied on the top, whitening and aggregation of the polymer component can be suppressed, and a liquid crystal alignment film excellent in coating film uniformity can be obtained. In addition, in addition to good initial characteristics, the liquid crystal alignment film can suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time. Therefore, the liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the present invention has excellent reliability, and is used for a large-screen high-definition liquid crystal television, a small-sized car navigation system, a smartphone, and the like. It can be suitably used.

  The present invention is described in detail below.

The present invention relates to a liquid crystal alignment treatment agent containing the following components (A) and (B), a liquid crystal alignment film obtained by using the liquid crystal alignment treatment agent, and a liquid crystal display element having the liquid crystal alignment film. is there.
Component (A): a polymer containing at least one selected from a polyimide precursor having a structure having a nitrogen atom and polyimide (also referred to as a specific polymer (A)).
Component (B): a polymer (specific polymer (B)) containing at least one selected from polyimide precursors and polyimides having a structure represented by the following formula [2] (also referred to as specific structure (2)) Also called).

（式［２］中、Ｙ^１およびＹ^７はそれぞれ独立して、単結合、炭素数１〜１０のアルキレン基、−Ｏ−、−Ｎ（Ｒ^１）−（Ｒ^１は水素原子または炭素数１〜３のアルキル基を示す）、−ＣＯＮ（Ｒ^２）−（Ｒ^２は水素原子または炭素数１〜３のアルキル基を示す）、−Ｎ（Ｒ^３）ＣＯ−（Ｒ^３は水素原子または炭素数１〜３のアルキル基を示す）、−ＣＨ_２Ｏ−、−ＣＯＯ−および−ＯＣＯ−から選ばれる少なくとも１種の有機基を示し、Ｙ^２およびＹ^６はそれぞれ独立して、炭素数１〜１０のアルキレン基を示し、Ｙ^３およびＹ^５はそれぞれ独立して、水素原子または炭素数１〜１０のアルキル基を示し、Ｙ^４は酸素原子または硫黄原子を示す）。

(Wherein [2], ^{Y 1} and ^{Y 7} are each independently a single bond, an alkylene group having 1 to 10 carbon ^{atoms, -O -, - N (R} 1) - (R 1 is a hydrogen atom or a carbon atoms 1 to 3 alkyl groups ), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom) Or an alkyl group having 1 to 3 carbon atoms), at least one organic group selected from —CH ₂ O—, —COO— and —OCO—, wherein Y ² and Y ⁶ are each independently carbon An alkylene group having 1 to 10 carbon atoms, Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and Y ⁴ represents an oxygen atom or a sulfur atom).

  The reason why the problem of the present invention is solved in the liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention is not necessarily clear, but is considered as follows.

  That is, the interaction between the nitrogen atom in the structure having a nitrogen atom contained in the specific polymer (A) and the carboxyl group (COOH group) in the specific polymer (B), and the above-mentioned in the specific polymer (B) The specific polymer (A) and the specific polymer (B) are compatible with each other by the interaction between the nitrogen atom in the formula [2] and the carboxyl group in the specific polymer (A). It is thought that precipitation of these polymer components during storage of the agent and whitening / aggregation when applied to the substrate can be suppressed.

  Moreover, it is thought that the structure which has a nitrogen atom in a specific polymer (A) can trap the ionic impurity component which is a factor which reduces a voltage holding rate. That is, the liquid crystal display element can trap ionic impurities that are generated by exposure to light for a long time, and accordingly, a decrease in voltage holding ratio can be suppressed.

  From the above points, the liquid crystal aligning agent containing at least one polymer selected from the polyimide precursor or polyimide having the specific structure of the present invention is excellent in the storage stability of the liquid crystal aligning agent, and the liquid crystal When the alignment treatment agent is applied onto the substrate, whitening and aggregation of the polymer component can be suppressed, and a liquid crystal alignment film excellent in coating film uniformity can be obtained. In addition, in addition to good initial characteristics, the liquid crystal alignment film can suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time.

<Structure having nitrogen atom>
The specific polymer (A) of the present invention is a polymer containing at least one selected from a polyimide precursor having a structure having a nitrogen atom and a polyimide.

  Specific examples of the structure having a nitrogen atom include structures represented by the following formulas [1a] to [1c].

In the formula [1a], X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring.

In the formula [1a], X ² represents a disubstituted amino group substituted with a hydrogen atom or an aliphatic group having 1 to 12 carbon atoms.

In the formula [1a], when X ² is a hydrogen atom, X ¹ represents a nitrogen-containing aromatic heterocyclic ring, and X ² is a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms. , X ¹ represents a benzene ring.

In the formula [1b], X ³ and X ⁷ each independently represent an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings.

In formula [1b], X ⁴ and X ⁶ each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

In the formula [1b], X ⁵ represents an alkylene group having 2 to ⁵ carbon atoms or a biphenyl group.

  In the formula [1b], m represents an integer of 0 or 1.

In formula [1c], X ⁸ and X ¹⁰ each independently represent at least one structure selected from structures represented by the following formula [1c-a] and formula [1c-b].

式［１ｃ］中、Ｘ^９は炭素数１〜５のアルキレン基またはベンゼン環を示す。

In the formula [1c], X ⁹ represents an alkylene group having 1 to 5 carbon atoms or a benzene ring.

<Specific structure (2)>
The specific polymer (B) of the present invention is a polymer containing at least one selected from a polyimide precursor having a specific structure (2) represented by the following formula [2] and a polyimide.

In Formula [2], Y ¹ and Y ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —S—, —N (R ¹ ) — (R ¹ is a hydrogen atom) Or an alkyl group having 1 to 3 carbon atoms), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ Represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), at least one organic group selected from —CH ₂ O—, —COO—, and —OCO—. Of these, a single bond, —O—, —S—, —OCO— or —COO— is preferable. More preferred is a single bond, —O— or —S— from the viewpoint of liquid crystal alignment properties and film hardness of the liquid crystal alignment film.

In formula [2], Y ² and Y ⁶ each independently represent an alkylene group having 1 to 10 carbon atoms. Among these, an alkylene group having 1 to 3 carbon atoms is preferable, and the structure may be either a straight chain or a branched chain. Specifically, from the viewpoint of liquid crystal alignment properties and film hardness of the liquid crystal alignment film, a methylene group (—CH ₂ —), an ethylene group (—CH ₂ CH ₂ ) having a structure with a free rotation portion and small steric hindrance. -), propylene (- _{(CH 2) 3} -) or an isopropyl group _{(-C (CH 2) 2 -} ) is preferred.

In formula [2], Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Of these, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable. Particularly preferred is a hydrogen atom.

In the formula [2], Y ⁴ represents an oxygen atom or a sulfur atom. Of these, oxygen atoms are preferred from the viewpoint of the film hardness of the liquid crystal alignment film.

<Specific polymer (A) / Specific polymer (B)>
The specific polymer (A) and the specific polymer (B) of the present invention are at least one polymer selected from a polyimide precursor and a polyimide (also collectively referred to as a polyimide polymer). Especially, it is preferable that the polyimide-type polymer of this invention is a polyimide precursor or a polyimide obtained by making a diamine component and a tetracarboxylic acid component react.

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

（式［Ａ］中、Ｒ^１は４価の有機基であり、Ｒ^２は２価の有機基であり、Ａ^１およびＡ^２はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示し、Ａ^３およびＡ^４はそれぞれ独立して、水素原子、炭素数１〜５のアルキル基またはアセチル基を示し、ｎは正の整数を示す）。

(In formula [A], R ¹ is a tetravalent organic group, R ² is a divalent organic group, and A ¹ and A ² are each independently a hydrogen atom or an alkyl having 1 to 5 carbon atoms. And A ³ and A ⁴ each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an acetyl group, and n represents a positive integer).

  Examples of the diamine component include diamine compounds having two primary or secondary amino groups in the molecule.

  Examples of the tetracarboxylic acid component include tetracarboxylic acid compounds, tetracarboxylic dianhydrides, tetracarboxylic acid dihalide compounds, tetracarboxylic acid dialkyl ester compounds, and tetracarboxylic acid dialkyl ester dihalide compounds.

In order to obtain a polyamic acid in which A ¹ and A ² in the formula [A] are hydrogen atoms, a diamine compound having two primary or secondary amino groups in the molecule, a tetracarboxylic acid compound or tetra It can be obtained by reacting with a carboxylic anhydride.

In order to obtain a polyamic acid alkyl ester in which A ¹ and A ² in the formula [A] are an alkyl group having 1 to 5 carbon atoms, the diamine compound, a tetracarboxylic acid dihalide compound, a tetracarboxylic acid dialkyl ester compound, or It can be obtained by reacting with a tetracarboxylic acid dialkyl ester dihalide compound. Further, the polyamic acid obtained by the method, it is also possible to introduce an alkyl group of 1 to 5 carbon atoms for A ¹ and A ² of the formula [A].

  The specific polymer (A) of the present invention is a polymer having a structure having a nitrogen atom. Especially, it is preferable that it is a structure shown by the said formula [1a]-a formula [1c].

  The method for introducing the structure having a nitrogen atom of the present invention into the specific polymer (A) is not particularly limited, but a diamine compound having a structure represented by the formulas [1a] to [1c] is used as a raw material. It is preferable to use it for the part.

  Specifically, it is preferable to use a diamine compound represented by the following formula [1-1] (also referred to as a specific diamine compound (1)).

In Formula [1-1], X ^A represents an organic group having at least one structure selected from the structures represented by Formula [1a] to Formula [1c].

In Formula [1-1], A ¹ and A ² each independently represent a hydrogen atom or an alkylene group having 1 to 5 carbon atoms.

  More specifically, diamine compounds represented by the following formulas [1a-1] to [1c-1] are preferably used.

In the formula [1a-1], X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring.

In the formula [1a-1], X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms.

In the formula [1a-1], when X ² is a hydrogen atom, X ¹ represents a nitrogen-containing aromatic heterocyclic ring, and X ² is a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms. In this case, X ¹ represents a benzene ring.

In formula [1b-1], X ³ and X ⁷ each independently represent an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings.

In formula [1b-1], X ⁴ and X ⁶ each independently represent a hydrogen atom or an alkylene group having 1 to 5 carbon atoms.

In the formula [1b-1], X ⁵ represents an alkylene group having 2 to ⁵ carbon atoms or a biphenyl group.

  In the formula [1b-1], m represents an integer of 0 or 1.

In formula [1c-1], X ⁸ and X ¹⁰ each independently represent at least one structure selected from structures represented by the following formulas [1c-a] and [1c-b].

In formula [1c-1], X ⁹ represents an alkylene group having 1 to 5 carbon atoms or a benzene ring.

  Specific diamine compounds of the specific diamine compound (1) of the present invention include diamine compounds represented by the following formulas [1-1a] to [1-4a].

In formula [1-3a], R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  In the formula [1-4a], n represents an integer of 1 to 10.

In formula [1-1a] to formula [1-4a], A ^{1 to} A ⁸ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  Especially, it is preferable to use the diamine compound shown by the said Formula [1-3a] or Formula [1-4a].

  The specific diamine compound (1) in the specific polymer (A) of the present invention is preferably 1 mol% to 95 mol% in 100 mol% of all diamine components. Especially, 5 mol%-95 mol% are preferable. More preferably, it is 20 mol% to 80 mol%.

  The specific diamine compound (1) of the present invention includes the solubility of the specific polymer (A) of the present invention in the solvent, the coating property of the liquid crystal alignment treatment agent, the liquid crystal alignment property when the liquid crystal alignment film is formed, the voltage holding ratio, One type or a mixture of two or more types can be used depending on characteristics such as accumulated charge.

  The specific polymer (B) of the present invention is a polymer having a specific structure (2).

  Although there is no restriction | limiting in particular in the method to introduce | transduce the specific structure (2) of this invention into a specific polymer (B), It is preferable to use the diamine compound which has a specific structure (2) for a diamine component. It is particularly preferable to use a diamine compound having a structure represented by the formula [2].

  Specifically, it is preferable to use a diamine compound represented by the following formula [2-1] (also referred to as a specific diamine compound (2)).

In Formula [2-1], Y ^A represents an organic group having a structure represented by Formula [2].

In Formula [2-1], A ¹ and A ² each independently represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

  More specifically, it is preferable to use a diamine compound represented by the following formula [2a].

In formula [2a], Y ¹ and Y ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —S—, —N (R ¹ ) — (R ¹ is a hydrogen atom) Or an alkyl group having 1 to 3 carbon atoms), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ Represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), at least one organic group selected from —CH ₂ O—, —COO—, and —OCO—. Of these, a single bond, —O—, —S—, —OCO— or —COO— is preferable. More preferably, it is a single bond, —O— or —S— which is a structure which is as flexible as possible and has a small steric hindrance in terms of liquid crystal orientation and film hardness.

In formula [2a], Y ² and Y ⁶ each independently represent an alkylene group having 1 to 10 carbon atoms. Among these, an alkylene group having 1 to 3 carbon atoms is preferable, and the structure may be either a straight chain or a branched chain. Specifically, from the viewpoint of liquid crystal alignment properties and film hardness of the liquid crystal alignment film, a methylene group (—CH ₂ —), an ethylene group (—CH ₂ CH ₂ ) having a structure with a free rotation portion and small steric hindrance. -), propylene (- _{(CH 2) 3} -) or an isopropyl group _{(-C (CH 2) 2 -} ) is preferred.

In formula [2a], Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms. Of these, a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable. Particularly preferred is a hydrogen atom.

In formula [2a], Y ⁴ represents an oxygen atom or a sulfur atom. Of these, oxygen atoms are preferred from the viewpoint of the film hardness of the liquid crystal alignment film.

Preferred combinations of Y ¹ , Y ² , Y ³ , Y ⁴ , Y ⁵ , Y ⁶ and Y ^{7 in} the formula [2a] are as shown in Table 1 below.

  Especially, the combination shown by Formula [2-1a], Formula [2-2a], Formula [2-4a], Formula [2-5a], Formula [2-7a], and Formula [2-8a] is preferable. .

In formula [2a], A ¹ and A ² each independently represent a hydrogen atom or an alkylene group having 1 to 5 carbon atoms.

  Specific diamine compounds of the specific diamine compound (2) of the present invention include diamine compounds represented by the following formulas [2-1a] to [2-3a].

（式［２−１ａ］〜式［２−３ａ］中、Ａ^１〜Ａ^６はそれぞれ独立して、水素原子または炭素数１〜５のアルキル基を示す）。

(In the formulas [2-1a] to [2-3a], A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms).

  The specific diamine compound (2) in the specific polymer (B) of the present invention is preferably 1 mol% to 95 mol% in 100 mol% of all diamine components. Especially, 5 mol%-95 mol% are preferable. More preferably, it is 20 mol% to 80 mol%.

  The specific diamine compound (2) of the present invention has the solubility in the solvent of the specific polymer (B) of the present invention, the coating property of the liquid crystal alignment treatment agent, the liquid crystal alignment property when it is used as a liquid crystal alignment film, the voltage holding ratio, One type or a mixture of two or more types can be used depending on characteristics such as accumulated charge.

  As a diamine component of the specific polymer (A) and the specific polymer (B) of the present invention, other diamines other than the specific diamine compound (1) and the specific diamine compound (2) unless the effects of the present invention are impaired. A compound (also referred to as other diamine compound) can be used.

  Specifically, 2,4-dimethyl-m-phenylenediamine, 2,6-diaminotoluene, m-phenylenediamine, p-phenylenediamine, 4,4′-diaminobiphenyl, 3,3′-dimethyl-4, 4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy-4,4'-diamino Biphenyl, 3,3′-difluoro-4,4′-biphenyl, 3,3′-trifluoromethyl-4,4′-diaminobiphenyl, 3,4′-diaminobiphenyl, 3,3′-diaminobiphenyl, 2, , 2′-diaminobiphenyl, 2,3′-diaminobiphenyl, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylmethane, 3, 4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2 ' -Diaminodiphenyl ether, 2,3'-diaminodiphenyl ether, 4,4'-sulfonyldianiline, 3,3'-sulfonyldianiline, bis (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl- Bis (4-aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4′-thiodianiline, 3,3′-thiodianiline, 4,4′-diaminodiphenylamine, 3,3′-diaminodiphenylamine, 3,4'-diaminodipheny Amine, 2,2′-diaminodiphenylamine, 2,3′-diaminodiphenylamine, N-methyl (4,4′-diaminodiphenyl) amine, N-methyl (3,3′-diaminodiphenyl) amine, N-methyl ( 3,4′-diaminodiphenyl) amine, N-methyl (2,2′-diaminodiphenyl) amine, N-methyl (2,3′-diaminodiphenyl) amine, 4,4′-diaminobenzophenone, 3,3 ′ -Diaminobenzophenone, 3,4'-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2'-diaminobenzophenone, 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1, , 7-Diaminonaphthalene, 1,8-diaminonaphthalene, 2,5-diaminonaphthalene 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-aminophenyl) ethane, 1,2-bis (3-aminophenyl) ethane, 1, 3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (4-aminophenyl) butane, 1,4-bis (3-aminophenyl) butane, Bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-amino) Phenyl) benzene, 1,3-bis (4-aminophenyl) benzene, 1,4-bis (4-aminobenzyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4′- 1,4-phenylenebis (methylene)] dianiline, 4,4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,4 ′-[1,4-phenylenebis (methylene)] dianiline, 3, 4 ′-[1,3-phenylenebis (methylene)] dianiline, 3,3 ′-[1,4-phenylenebis (methylene)] dianiline, 3,3 ′-[1,3-phenylenebis (methylene)] Dianiline, 1,4-phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylenebis [(3-aminophenyl) methanone], 1,4-phenylenebis (4-aminobenzoate), 1,4-phenylenebis (3-amino Zoate), 1,3-phenylenebis (4-aminobenzoate), 1,3-phenylenebis (3-aminobenzoate), bis (4-aminophenyl) terephthalate, bis (3-aminophenyl) terephthalate, bis (4 -Aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, N, N '-(1,4-phenylene) bis (4-aminobenzamide), N, N'-(1,3-phenylene) bis (4-aminobenzamide), N, N ′-(1,4-phenylene) bis (3-aminobenzamide), N, N ′-(1,3-phenylene) bis (3-aminobenzamide), N, N '-Bis (4-aminophenyl) terephthalamide, N, N'-bis (3-aminophenyl) terephthalamide, N, N'-bis (4- Aminophenyl) isophthalamide, N, N′-bis (3-aminophenyl) isophthalamide, 9,10-bis (4-aminophenyl) anthracene, 4,4′-bis (4-aminophenoxy) diphenylsulfone, 2 , 2′-bis [4- (4-aminophenoxy) phenyl] propane, 2,2′-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2′-bis (4-aminophenyl) ) Hexafluoropropane, 2,2′-bis (3-aminophenyl) hexafluoropropane, 2,2′-bis (3-amino-4-methylphenyl) hexafluoropropane, 2,2′-bis (4- Aminophenyl) propane, 2,2′-bis (3-aminophenyl) propane, 2,2′-bis (3-amino-4-methylpheny) ) Propane, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3- Aminophenoxy) butane, 1,5-bis (4-aminophenoxy) pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,6-bis (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- (3-aminophenoxy) heptane, 1,8-bis (4-aminophenoxy) octane, 1,8 -Bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3-aminophenoxy) nonane, 1,10- (4-amino Phenoxy) decane, 1,10- (3-aminophenoxy) decane, 1,11- (4-aminophenoxy) undecane, 1,11- (3-aminophenoxy) undecane, 1,12- (4-aminophenoxy) Dodecane, 1,12- (3-aminophenoxy) dodecane, bis (4-aminocyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) methane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane or 1 , 12-diaminododecane, and diamine compounds in which these amino groups are secondary amino groups. It is done.

  Moreover, the diamine compound which has a long-chain alkyl group with high hydrophobicity in the side chain of a diamine compound can also be used.

  Other diamine compounds of the present invention include the solubility of the specific polymer (A) and the specific polymer (B) of the present invention in a solvent, the coating property of a liquid crystal aligning agent, and the liquid crystal alignment properties when used as a liquid crystal alignment film. One type or a mixture of two or more types can be used depending on characteristics such as voltage holding ratio and accumulated charge.

  As the specific polymer (A) and specific polymer (B) of the present invention, that is, the tetracarboxylic acid component for producing these polyimide polymers, tetracarboxylic dianhydride represented by the following formula [3] It is preferable to use a product. At that time, not only the tetracarboxylic dianhydride represented by the formula [3] but also the tetracarboxylic acid derivative tetracarboxylic acid, tetracarboxylic acid dihalide compound, tetracarboxylic acid dialkyl ester compound or tetracarboxylic acid dialkyl ester di Halide compounds can also be used (the tetracarboxylic dianhydride represented by the formula [3] and its derivatives are collectively referred to as a specific tetracarboxylic acid component).

（式［３］中、Ｚは下記の式［３ａ］〜式［３ｋ］で示される構造から選ばれる少なくとも１種の構造を示す）。

(In formula [3], Z represents at least one structure selected from structures represented by formula [3a] to formula [3k] below).

In the formula [3a], Z ^{1 to} Z ⁴ represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring, and may be the same or different.

In formula [3g], Z ⁵ and Z ⁶ each independently represent a hydrogen atom or a methyl group, and may be the same or different.

  Of the Z in the formula [3], the formula [3a], the formula [3c] to the formula [3g] or the formula [3k] are used from the viewpoint of easy synthesis and easy polymerization reactivity when producing a polymer. ] The tetracarboxylic dianhydride of the structure shown by these and its tetracarboxylic acid derivative are preferable. More preferable is the structure represented by the formula [3a] or the formula [3e] to the formula [3g]. Particularly preferred are tetracarboxylic dianhydrides and their tetracarboxylic acid derivatives having the structure represented by the formula [3a], the formula [3e] or the formula [3f].

  The specific tetracarboxylic acid component in the specific polymer (A) and the specific polymer (B) of the present invention is preferably 1 mol% to 100 mol% in 100 mol% of all tetracarboxylic acid components. Especially, 5 mol%-95 mol% are preferable. More preferably, it is 20 mol% to 80 mol%.

  The specific tetracarboxylic acid component of the present invention includes the solubility of the specific polymer (A) and the specific polymer (B) of the present invention in a solvent, the coating property of a liquid crystal aligning agent, and the liquid crystal alignment film. One type or a mixture of two or more types can be used depending on the properties such as orientation, voltage holding ratio, and accumulated charge.

  As long as the effects of the present invention are not impaired, other tetracarboxylic acid components other than the specific tetracarboxylic acid component are used for the specific polymer (A) and the polyimide polymer of the specific polymer (B). You can also.

  Examples of other tetracarboxylic acid components include the following tetracarboxylic acid compounds, tetracarboxylic dianhydrides, tetracarboxylic acid dihalide compounds, tetracarboxylic acid dialkyl ester compounds, and tetracarboxylic acid dialkyl ester dihalide compounds.

  That is, as other tetracarboxylic acid components, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 1,2,5,6-anthracenetetracarboxylic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid, 2,3,3 ′, 4-biphenyltetracarboxylic acid, bis (3,4-dicarboxyphenyl) ether, 3,3 ′, 4,4 ′ -Benzophenone tetracarboxylic acid, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1, 1,3,3,3-hexafluoro-2,2-bis (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bi (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3,4-dicarboxyphenyl) pyridine, 3,3 ′, 4,4 ′ -Diphenylsulfonetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid or 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid.

  The other tetracarboxylic acid component of the present invention includes the solubility of the specific polymer (A) and the specific polymer (B) of the present invention in a solvent, the coating property of a liquid crystal aligning agent, and the liquid crystal alignment film. One type or a mixture of two or more types can be used depending on the properties such as orientation, voltage holding ratio, and accumulated charge.

<Method for Producing Specific Polymer (A) / Specific Polymer (B)>
In the present invention, the specific polymer (A) and the specific polymer (B), that is, methods for producing these polyimide polymers are not particularly limited. Usually, it is obtained by reacting a diamine component and a tetracarboxylic acid component. In general, at least one tetracarboxylic acid component selected from the group consisting of tetracarboxylic dianhydrides and their derivatives is reacted with a diamine component consisting of one or more diamine compounds. And a method of obtaining a polyamic acid. Specifically, a method of obtaining polyamic acid by polycondensation of tetracarboxylic dianhydride and primary or secondary diamine compound, dehydration polycondensation reaction of tetracarboxylic acid and primary or secondary diamine compound A method of obtaining polyamic acid by polycondensation of a tetracarboxylic acid dihalide and a primary or secondary diamine compound is used.

  In order to obtain the polyamic acid alkyl ester, a method of polycondensing a tetracarboxylic acid obtained by dialkyl esterifying a carboxylic acid group with a primary or secondary diamine compound, a tetracarboxylic acid dihalide obtained by dialkyl esterifying a carboxylic acid group, and A method of polycondensation with a primary or secondary diamine compound or a method of converting a carboxyl group of a polyamic acid into an ester is used.

  In order to obtain polyimide, a method is used in which the polyamic acid or polyamic acid alkyl ester is cyclized to form polyimide.

  The reaction between the diamine component and the tetracarboxylic acid component is usually carried out in a solvent with the diamine component and the tetracarboxylic acid component. The solvent used at that time is not particularly limited as long as the produced polyimide precursor is soluble. Although the specific example of the solvent used for reaction below is given, it is not limited to these examples.

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

（式［Ｄ−１］中、Ｄ^１は炭素数１〜３のアルキル基を示し、式［Ｄ−２］中、Ｄ^２は炭素数１〜３のアルキル基を示し、式［Ｄ−３］中、Ｄ^３は炭素数１〜４のアルキル基を示す）。

(In the formula [D-1], D ¹ represents an alkyl group having 1 to 3 carbon atoms, and in the formula [D-2], D ² represents an alkyl group having 1 to 3 carbon atoms, and the formula [D-3 ], D < ³ > shows a C1-C4 alkyl group .

  These solvents may be used alone or in combination. Furthermore, even if it is a solvent which does not dissolve a polyimide precursor, you may mix and use it for the said solvent in the range which the produced | generated polyimide precursor does not precipitate. Moreover, since water in the solvent inhibits the polymerization reaction and further causes hydrolysis of the produced polyimide precursor, it is preferable to use a dehydrated and dried solvent.

  When the diamine component and the tetracarboxylic acid component are reacted in a solvent, the solution in which the diamine component is dispersed or dissolved in the solvent is stirred, and the tetracarboxylic acid component is added as it is or dispersed or dissolved in the solvent. Methods, conversely, a method of adding a diamine component to a solution in which a tetracarboxylic acid component is dispersed or dissolved in a solvent, a method of alternately adding a diamine component and a tetracarboxylic acid component, etc., and any of these methods May be used. In addition, when reacting using a plurality of diamine components or tetracarboxylic acid components, they may be reacted in a premixed state, individually or sequentially, or further individually reacted low molecular weight substances. May be mixed and reacted to form a polymer. Although the polymerization temperature in that case can select the arbitrary temperature of -20 degreeC-150 degreeC, Preferably it is the range of -5 degreeC-100 degreeC. The reaction can be carried out at any concentration, but if the concentration is too low, it is difficult to obtain a high molecular weight polymer, and if the concentration is too high, the viscosity of the reaction solution becomes too high and uniform stirring is difficult. It becomes. Therefore, Preferably it is 1-50 mass%, More preferably, it is 5-30 mass%. The initial reaction can be carried out at a high concentration, and then a solvent can be added.

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

  The polyimide of the present invention is a polyimide obtained by ring closure of the polyimide precursor, and in this polyimide, the ring closure rate (also referred to as imidation rate) of the amic acid group is not necessarily 100%. It can be arbitrarily adjusted according to the purpose.

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

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

  The catalyst imidation of the polyimide precursor is performed by adding a basic catalyst and an acid anhydride to the polyimide precursor solution and stirring at -20 ° C to 250 ° C, preferably 0 ° C to 180 ° C. it can. The amount of the basic catalyst is 0.5 to 30 mol times, preferably 2 to 20 mol times of the amic acid group, and the amount of the acid anhydride is 1 to 50 mol times of the amic acid group, Preferably they are 3 mol times-30 mol times. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. 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.

  When recovering the produced polyimide precursor or polyimide from the polyimide precursor or polyimide reaction solution, the reaction solution may be poured into a solvent and precipitated. Examples of the solvent used for precipitation include methanol, ethanol, isopropyl alcohol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polymer precipitated in the solvent can be collected by filtration, and then dried by normal temperature or reduced pressure at room temperature or by heating. Moreover, when the polymer which carried out precipitation collection is re-dissolved in a solvent and the operation which carries out reprecipitation collection is repeated 2-10 times, the impurity in a polymer can be decreased. Examples of the solvent at this time include alcohols, ketones, and hydrocarbons, and it is preferable to use three or more kinds of solvents selected from these because purification efficiency is further increased.

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

  As the specific polymer (A) of the present invention, any polyimide polymer of polyamic acid, polyamic acid alkyl ester and polyimide may be used. Of these, polyamic acid alkyl ester or polyimide is preferable. More preferably, it is a polyimide. Specifically, a polyimide having an imidization rate of 50% or more is preferable, and a polyimide having an imidization rate of 70% or more is more preferable.

  As the specific polymer (B) of the present invention, any polyimide polymer of polyamic acid, polyamic acid alkyl ester and polyimide may be used. Of these, polyamic acid or polyamic acid alkyl ester is preferable. More preferred is polyamic acid.

  The ratio of the specific polymer (A) and the specific polymer (B) in the liquid crystal aligning agent of the present invention is 0.5 mass for the specific polymer (B) with respect to 100 mass parts of the specific polymer (A). Parts to 950 parts by mass are preferred. Especially, 10 mass parts-900 mass parts are preferable, and 10 mass parts-400 mass parts are more preferable.

  All of the polymer components in the liquid crystal aligning agent of the present invention may be the specific polymer (A) and the specific polymer (B) of the present invention, and other polymers are mixed. May be. Examples of the other polymer include the polyimide polymer not having a structure having a nitrogen atom and the polyimide polymer not having a specific structure (2) according to the present invention. Furthermore, a cellulose polymer, an acrylic polymer, a methacrylic polymer, polystyrene, polyamide, or polysiloxane may be used. At that time, the content of the other polymer other than that is 0.5 parts by mass with respect to 100 parts by mass of the specific polymer (A) and the specific polymer (B) of the present invention. -30 mass parts. Especially, 1 mass part-20 mass parts are preferable.

  Moreover, it is preferable that content of the solvent in the liquid-crystal aligning agent of this invention is 70 mass%-99.9 mass%. This content can be appropriately changed depending on the application method of the liquid crystal aligning agent and the film thickness of the target liquid crystal alignment film.

  The solvent used for the liquid crystal aligning agent of this invention will not be specifically limited if it is a solvent (it is also called a good solvent) in which a specific polymer (A) and a specific polymer (B) are dissolved. Although the specific example of a good solvent is given to the following, it is not limited to these examples.

  For example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-imidazolidinone, methyl ethyl ketone , Cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, and the like.

  Of these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and γ-butyrolactone are preferably used.

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

It is preferable that the good solvent in the liquid-crystal aligning agent of this invention is 20 mass%-99 mass% of the whole solvent contained in a liquid-crystal aligning agent. Especially, 20 mass%-90 mass% are preferable. More preferably, it is 30% by mass to 80% by mass.

  The liquid crystal aligning agent of the present invention uses a solvent (also referred to as a poor solvent) that improves the coating properties and surface smoothness of the liquid crystal aligning film when the liquid crystal aligning agent is applied unless the effects of the present invention are impaired. be able to. Although the specific example of a poor solvent is given to the following, it is not limited to these examples.

  For example, ethanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, isopentyl alcohol, tert-pentyl alcohol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol, 2-ethyl-1-butanol, 1-heptanol 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 1,2- Etanji 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentane Diol, 2-methyl-2,4-pentanediol, 2-ethyl-1,3-hexanediol, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2-hexanone, 2 Heptanone, 4-heptanone, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate 2- (methoxymethoxy) ethanol, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, 2- (hexyloxy) ethanol, furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monobutyl ether, 1- (Butoxyethoxy) propanol, propylene glycol monomethyl ether acetate, dipropylene glycol, Dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monoacetate Tar, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2- (2-ethoxyethoxy) ethyl acetate, diethylene glycol acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol Monoethyl ether, milk Methyl, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, 3-methoxypropion Ethyl acid, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, lactic acid Examples thereof include isoamyl esters and solvents represented by the above formulas [D-1] to [D-3].

  Among these, 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether or dipropylene glycol dimethyl ether is preferably used.

  It is preferable that these poor solvents are 1 mass%-80 mass% of the whole solvent contained in a liquid-crystal aligning agent. Especially, 10 mass%-80 mass% are preferable. More preferably, it is 20 mass%-70 mass%.

  The liquid crystal aligning agent of the present invention has at least one substitution selected from the group consisting of a crosslinkable compound having an epoxy group, an isocyanate group, an oxetane group or a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group and a lower alkoxyalkyl group. It is preferable to introduce a crosslinkable compound having a group or a crosslinkable compound having a polymerizable unsaturated bond. It is necessary to have two or more of these substituents and polymerizable unsaturated bonds in the crosslinkable compound.

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

  The crosslinkable compound having an oxetane group is a crosslinkable compound having at least two oxetane groups represented by the following formula [4A].

  Specific examples include crosslinkable compounds represented by the formulas [4a] to [4k] published on pages 58 to 59 of International Publication No. WO2011 / 132751 (published 2011.10.27).

  The crosslinkable compound having a cyclocarbonate group is a crosslinkable compound having at least two cyclocarbonate groups represented by the following formula [5A].

  Specifically, the crosslinkable compounds represented by the formulas [5-1] to [5-42] described on pages 76 to 82 of International Publication No. WO2012 / 014898 (published on 2012.2.2) are listed. It is done.

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

  As an example of such a melamine derivative or a benzoguanamine derivative, MX-750 in which an average of 3.7 methoxymethyl groups is substituted per one triazine ring of a commercially available product, and an average of 5. methoxymethyl groups per one triazine ring. 8-substituted MW-30 (Sanwa Chemical Co., Ltd.) and Cymel 300, 301, 303, 350, 370, 771, 325, 327, 703, 712 and other methoxymethylated melamines, Cymel 235, 236 Methoxymethylated butoxymethylated melamine such as 238, 212, 253, and 254, butoxymethylated melamine such as Cymel 506 and 508, carboxyl group-containing methoxymethylated isobutoxymethylated melamine such as Cymel 1141, Cymel 1123 and the like Methoxymethylated etoxy Methylated benzoguanamine, methoxymethylated butoxymethylated benzoguanamine such as Cymel 1123-10, butoxymethylated benzoguanamine such as Cymel 1128, carboxyl group-containing methoxymethylated ethoxymethylated benzoguanamine such as Cymel 1125-80 (Cyanamide). Examples of glycoluril include butoxymethylated glycoluril such as Cymel 1170, methylolated glycoluril such as Cymel 1172, and methoxymethylolated glycoluril such as Powderlink 1174.

  Examples of the benzene or phenolic compound having a hydroxyl group or an alkoxyl group include 1,3,5-tris (methoxymethyl) benzene, 1,2,4-tris (isopropoxymethyl) benzene, 1,4-bis ( sec-butoxymethyl) benzene or 2,6-dihydroxymethyl-p-tert-butylphenol.

  More specifically, the crosslinkable compounds represented by the formulas [6-1] to [6-48], which are published on pages 62 to 66 of International Publication No. WO2011 / 132751 (published 2011.10.27). Is mentioned.

  Examples of the crosslinkable compound having a polymerizable unsaturated bond include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, and tri (meth) acryloyloxyethoxytrimethylol. Crosslinkable compounds having three polymerizable unsaturated groups in the molecule such as propane or glycerin polyglycidyl ether poly (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (Meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene glycol Di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide bisphenol A type di (meth) acrylate, propylene oxide bisphenol type di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin Di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, diglycidyl phthalate di (meth) acrylate or hydroxypivalic acid neo A crosslinkable compound having two polymerizable unsaturated groups in the molecule, such as pentyl glycol di (meth) acrylate, in addition to 2-hydroxyethyl (meth) acrylate 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 3-chloro It has one polymerizable unsaturated group in the molecule such as 2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl phosphate ester, or N-methylol (meth) acrylamide. Examples thereof include a crosslinkable compound.

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

（式［７Ａ］中、Ｅ^１はシクロヘキサン環、ビシクロヘキサン環、ベンゼン環、ビフェニル環、ターフェニル環、ナフタレン環、フルオレン環、アントラセン環またはフェナントレン環からからなる群から選ばれる基を示し、Ｅ^２は下記の式［７ａ］または式［７ｂ］から選ばれる基を示し、ｎは１〜４の整数を示す）。

(In the formula [7A], E ¹ represents a group selected from the group consisting of a cyclohexane ring, a bicyclohexane ring, a benzene ring, a biphenyl ring, a terphenyl ring, a naphthalene ring, a fluorene ring, an anthracene ring or a phenanthrene ring; ² represents a group selected from the following formula [7a] or [7b], and n represents an integer of 1 to 4.

  The said compound is an example of a crosslinkable compound, It is not limited to these. Moreover, the crosslinkable compound used for the liquid-crystal aligning agent of this invention may be 1 type, and may be combined 2 or more types.

  It is preferable that content of the crosslinkable compound in the liquid-crystal aligning agent of this invention is 0.1 mass part-150 mass parts with respect to 100 mass parts of all the polymer components. Especially, in order for a crosslinking reaction to advance and to express the target effect, 0.1 mass part-100 mass parts are preferable with respect to 100 mass parts of all the polymer components. More preferred is 1 part by mass to 50 parts by mass.

  As long as the liquid crystal aligning agent of the present invention does not impair the effects of the present invention, a compound that improves the uniformity and surface smoothness of the liquid crystal aligning film when the liquid crystal aligning agent is applied can be used.

  Examples of the compound that improves the film thickness uniformity and surface smoothness of the liquid crystal alignment film include fluorine-based surfactants, silicone-based surfactants, and nonionic surfactants.

  More specifically, for example, F-top EF301, EF303, EF352 (above, manufactured by Tochem Products), MegaFuck F171, F173, R-30 (above, manufactured by Dainippon Ink), Florard FC430, FC431 (or more , Manufactured by Sumitomo 3M Limited), Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (above, manufactured by Asahi Glass).

  The use ratio of these surfactants is preferably 0.01 parts by mass to 2 parts by mass, more preferably 0.01 parts by mass with respect to 100 parts by mass of all the polymer components contained in the liquid crystal aligning agent. -1 part by mass.

  Furthermore, in the liquid crystal alignment treatment agent of the present invention, as a compound that promotes charge transfer in the liquid crystal alignment film and promotes charge loss of the element, page 69 of International Publication No. WO2011 / 132751 (published 2011.10.20). It is also possible to add a nitrogen-containing heterocyclic amine compound represented by the formula [M1] to the formula [M156], which is listed on page 73. This amine compound may be added directly to the liquid crystal aligning agent, but it is added after a solution having a concentration of 0.1% by mass to 10% by mass, preferably 1% by mass to 7% by mass with an appropriate solvent. It is preferable. The solvent is not particularly limited as long as it is a solvent that dissolves the specific polymer (A) and the specific polymer (B) described above.

  The liquid crystal alignment treatment agent of the present invention includes, in addition to the above poor solvent, crosslinkable compound, resin film or compound that improves the film thickness uniformity and surface smoothness of the liquid crystal alignment film, and a compound that promotes charge removal, As long as the effects of the present invention are not impaired, a dielectric or conductive material for changing the electrical characteristics such as the dielectric constant and conductivity of the liquid crystal alignment film may be added.

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

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

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

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

  As a method for manufacturing a liquid crystal cell, prepare a pair of substrates on which a liquid crystal alignment film is formed, spray spacers on the liquid crystal alignment film of one substrate, and place the other side of the liquid crystal alignment film on the other side. And a method of sealing the substrate by injecting liquid crystal under reduced pressure, or a method of bonding the substrate after dropping the liquid crystal on the surface of the liquid crystal alignment film on which the spacers are dispersed, and the like.

  As described above, the liquid crystal aligning agent of the present invention has excellent storage stability of the liquid crystal aligning agent, and suppresses whitening and aggregation of the polymer component when the liquid crystal aligning agent is applied on the substrate. And the liquid crystal aligning film excellent in the coating-film uniformity can be obtained. In addition, in addition to good initial characteristics, the liquid crystal alignment film can suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time. Therefore, the liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the present invention has excellent reliability, and is used for a large-screen high-definition liquid crystal television, a small-sized car navigation system, a smartphone, and the like. It can be suitably used.

The present invention will be described in more detail with reference to the following examples, but is not limited thereto.
"Abbreviations used in the synthesis examples, examples and comparative examples of the present invention"
Abbreviations used in the synthesis examples, examples and comparative examples are as follows.

<Monomer for producing the polyimide polymer of the present invention>
(Specific diamine compound (1) of the present invention)
A1: Diamine compound represented by the following formula [A1] A2: Diamine compound represented by the following formula [A2]

(Specific diamine compound (2) of the present invention)
B1: Diamine compound represented by the following formula [B1]

(Other diamine compounds)
C1: p-phenylenediamine C2: diamine compound represented by the following formula [C2] C3: diamine compound represented by the following formula [C3]

(Specific tetracarboxylic acid component of the present invention)
D1: 1,2,3,4-cyclobutanetetracarboxylic dianhydride D2: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride D3: the following formula [D3 ] The tetracarboxylic dianhydride shown by this

(Other tetracarboxylic acid components)
E1: pyromellitic dianhydride

"Crosslinkable compound used in the present invention"
K1: Crosslinkable compound represented by the following formula [K1]

"Solvent used in the present invention"
NMP: N-methyl-2-pyrrolidone γ-BL: γ-butyrolactone BCS: ethylene glycol monobutyl ether DPM: dipropylene glycol monomethyl ether

"Measurement of molecular weight of polyimide polymer of the present invention"
The molecular weights of the polyimide precursor and the polyimide in the synthesis example are obtained by using a normal temperature gel permeation chromatography (GPC) apparatus (GPC-101) (manufactured by Showa Denko KK) and a column (KD-803, KD-805) (manufactured by Shodex). The measurement was performed as follows.

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

"Measurement of imidization ratio of polyimide of the present invention"
The imidation ratio of polyimide in the synthesis example was measured as follows. 20 mg of polyimide powder was put into an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube standard, φ5 (manufactured by Kusano Kagaku)), and deuterated dimethyl sulfoxide (DMSO-d6, 0.05 mass% TMS (tetramethylsilane)). (Mixed product) (0.53 ml) was added and completely dissolved by applying ultrasonic waves. This solution was measured for proton NMR at 500 MHz with an NMR measuring instrument (JNW-ECA500) (manufactured by JEOL Datum). The imidation rate is determined based on protons derived from structures that do not change before and after imidation as reference protons, and the peak integrated value of these protons and proton peaks derived from NH groups of amic acid appearing in the vicinity of 9.5 ppm to 10.0 ppm. Using the integrated value, the following formula was used.

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

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

"Synthesis of polyimide polymer of the present invention"
<Synthesis Example 1>
D3 (13.5 g, 45.0 mmol), B1 (2.69 g, 9.02 mmol), C1 (3.40 g, 31.4 mmol) and C3 (1.56 g, 4.48 mmol) were converted to NMP (84.7 g). Then, the mixture was reacted at 40 ° C. for 20 hours to obtain a polyamic acid solution having a resin solid content concentration of 20% by mass. The viscosity of this polyamic acid at a temperature of 25 ° C. was 900 mPa · s.

  After diluting the resulting polyamic acid solution (80.0 g) with NMP (200.0 g), acetic anhydride (36.5 g) and pyridine (17.0 g) were added as an imidization catalyst at 40 ° C. The reaction was performed for 3 hours. This reaction solution was poured into methanol (1170 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (1). The imidation ratio of this polyimide was 85%, the number average molecular weight was 11,900, and the weight average molecular weight was 28,500.

<Synthesis Example 2>
D2 (2.25 g, 8.99 mmol), D3 (10.8 g, 36.0 mmol), B1 (2.68 g, 8.98 mmol), C1 (3.40 g, 31.4 mmol) and C3 (1.57 g, 4.50 mmol) was mixed in NMP (82.9 g) and reacted at 40 ° C. for 24 hours to obtain a polyamic acid solution having a resin solid content concentration of 20 mass%. The viscosity of this polyamic acid at a temperature of 25 ° C. was 980 mPa · s.

  After diluting the resulting polyamic acid solution (80.0 g) with NMP (200.0 g), acetic anhydride (37.2 g) and pyridine (17.3 g) were added as an imidization catalyst at 40 ° C. The reaction was performed for 3 hours. This reaction solution was poured into methanol (1170 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (2). The imidation ratio of this polyimide was 65%, the number average molecular weight was 10,200, and the weight average molecular weight was 21,500.

<Synthesis Example 3>
D1 (3.92 g, 20.0 mmol), E1 (3.66 g, 16.8 mmol), A2 (2.55 g, 12.0 mmol) and C2 (5.55 g, 28.0 mmol) NMP (44.2 g) And in γ-BL (44.2 g) and reacted at 25 ° C. for 2 hours to obtain a polyamic acid solution (3) having a resin solid content concentration of 15% by mass. The viscosity of this polyamic acid at a temperature of 25 ° C. was 340 mPa · s. The number average molecular weight of this polyamic acid was 14,200, and the weight average molecular weight was 29,900.

<Synthesis Example 4>
D1 (3.92 g, 20.0 mmol), E1 (3.66 g, 16.8 mmol), A1 (2.39 g, 12.0 mmol) and C2 (5.55 g, 28.0 mmol) were added to NMP (44.2 g). And in γ-BL (44.2 g) and reacted at 25 ° C. for 2 hours to obtain a polyamic acid solution (4) having a resin solid content concentration of 15% by mass. The viscosity of this polyamic acid at a temperature of 25 ° C. was 330 mPa · s. The number average molecular weight of this polyamic acid was 13,300, and the weight average molecular weight was 27,900.

<Synthesis Example 5>
D1 (5.65 g, 28.8 mmol), D3 (2.40 g, 7.9 mmol), A1 (6.38 g, 32.0 mmol) and C2 (1.58 g, 7.97 mmol) were combined with NMP (44.2 g). And γ-BL (44.2 g) were mixed and reacted at 25 ° C. for 2 hours to obtain a polyamic acid solution (5) having a resin solid content concentration of 10% by mass. The viscosity of this polyamic acid at a temperature of 25 ° C. was 170 mPa · s. The number average molecular weight of this polyamic acid was 16,700, and the weight average molecular weight was 35,700.

<Synthesis Example 6>
D3 (14.4 g, 48.0 mmol), C1 (4.67 g, 43.2 mmol) and C3 (1.67 g, 4.79 mmol) were mixed in NMP (83.0 g) and reacted at 40 ° C. for 20 hours. Thus, a polyamic acid solution having a resin solid content concentration of 20% by mass was obtained. The viscosity of this polyamic acid at a temperature of 25 ° C. was 890 mPa · s.

  After diluting the resulting polyamic acid solution (80.0 g) with NMP (200.0 g), acetic anhydride (41.7 g) and pyridine (19.1 g) were added as an imidization catalyst at 40 ° C. The reaction was performed for 3 hours. This reaction solution was poured into methanol (1190 ml), and the resulting precipitate was filtered off. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyimide powder (6). The imidation ratio of this polyimide was 85%, the number average molecular weight was 10,300, and the weight average molecular weight was 22,800.

<Synthesis Example 7>
D1 (3.92 g, 20.0 mmol), E1 (3.66 g, 16.8 mmol) and C2 (7.93 g, 40.0 mmol) in NMP (44.2 g) and γ-BL (44.2 g). The mixture was reacted at 25 ° C. for 2 hours to obtain a polyamic acid solution (7) having a resin solid content concentration of 15% by mass. The viscosity of this polyamic acid at a temperature of 25 ° C. was 330 mPa · s. The number average molecular weight of this polyamic acid was 13,600, and the weight average molecular weight was 34,200.

  Table 2 shows the polyimide polymers of the present invention.

＊１：ポリアミド酸。

* 1: Polyamic acid.

“Production of Liquid Crystal Alignment Treatment Agent of the Present Invention”
In Examples 1 to 6 and Comparative Examples 1 to 3 described below, production examples of liquid crystal alignment treatment agents are described. Moreover, this liquid crystal aligning agent is used also for evaluation.

  The liquid crystal aligning agents of the present invention are shown in Table 3 and Table 4.

  Using the liquid crystal alignment treatment agents obtained in the examples and comparative examples of the present invention, "Evaluation of storage stability of liquid crystal alignment treatment agents", "Evaluation of whitening and aggregation of liquid crystal alignment treatment agents" and "Voltage holding ratio" Evaluation "was performed.

"Evaluation of storage stability of liquid crystal alignment treatment agent"
The liquid crystal aligning agents obtained in Examples and Comparative Examples of the present invention were pressure filtered through a membrane filter having a pore diameter of 1 μm and stored at −15 ° C. for 48 hours. Thereafter, the occurrence of turbidity and precipitates in the liquid crystal aligning agent was confirmed by visual observation.

  Tables 5 and 6 show the results obtained in the examples and comparative examples. In the table, turbidity and precipitates were not observed, and the solution was a uniform solution, and turbidity and precipitates were observed as x.

  Also, the ITO surface of the substrate with 30 × 40 mm ITO electrodes (40 mm long × 30 mm wide, 0.7 mm thick) obtained by washing the liquid crystal aligning agent stored at −15 ° C. for 48 hours with pure water and IPA And an ITO substrate with a liquid crystal alignment film was prepared by heat treatment at 100 ° C. for 5 minutes on a hot plate. And the pinhole of the obtained board | substrate with a liquid crystal aligning film was evaluated.

  The evaluation was performed by visually observing the substrate under a sodium lamp. Specifically, the number of pinholes observed on the substrate with a liquid crystal alignment film was counted, and the smaller the number of pinholes, the smaller the precipitates in the liquid crystal alignment treatment agent, and the better this evaluation was (Table) 5 and Table 6 show the number of pinholes).

  Tables 5 and 6 show the results obtained in the examples and comparative examples.

"Evaluation of whitening and aggregation of liquid crystal alignment agents"
The liquid crystal aligning agent obtained in the examples and comparative examples of the present invention was filtered under pressure with a membrane filter having a pore diameter of 1 μm, and 1 ml was dropped on a 100 × 100 mm Cr substrate. Then, it was allowed to stand in an environment of a temperature of 27 ° C. and a humidity of 65%, and the time until turbidity (whitening / aggregation) occurred in the dropped liquid crystal alignment treatment agent was measured.

  In the evaluation, the longer the time until turbidity occurred, the better the whitening / aggregation characteristics of the liquid crystal aligning agent (the times are shown in Tables 5 and 6).

  Tables 5 and 6 show the results obtained in the examples and comparative examples.

"Evaluation of voltage holding ratio"
40 × 30 mm ITO electrode substrate (40 mm × 40 mm) obtained by pressure-filtering the liquid crystal aligning agent obtained in the examples and comparative examples of the present invention with a membrane filter having a pore diameter of 1 μm and washing with pure water and IPA. The film is spin-coated on an ITO surface with a width of 30 mm and a thickness of 0.7 mm, and heat-treated on a hot plate at 80 ° C. for 90 seconds and in an IR (infrared) type clean oven at 230 ° C. for 15 minutes. Obtained an ITO substrate with a polyimide liquid crystal alignment film of 100 nm.

  A rubbing apparatus having a roll diameter of 120 mm was used to rub the coated surface of the ITO substrate with a roll of 1000 rpm, a roll traveling speed of 35 mm / sec, and a pushing amount of 0.7 mm.

  Two ITO substrates with this liquid crystal alignment film were prepared, combined with a 4 μm spacer sandwiched with the liquid crystal alignment film surface on the inside, and the periphery was adhered with a sealant to produce an empty cell. MLC-3018U (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 liquid crystal cell.

  The voltage holding ratio was evaluated using the obtained liquid crystal cell. Specifically, a voltage of 4 V was applied for 60 μs at a temperature of 90 ° C., a voltage after 166.7 ms was measured, and how much the voltage could be held was calculated as a voltage holding ratio (also referred to as VHR). The measurement was performed using a voltage holding ratio measuring device (VHR-1) (manufactured by Toyo Technica Co., Ltd.) with settings of Voltage: ± 1 V, Pulse Width: 60 μs, and Frame Period: 166.7 ms.

Furthermore, 5 J / cm ² of ultraviolet rays in terms of 365 nm was converted into a liquid crystal cell for which the measurement of the voltage holding ratio immediately after the production of the liquid crystal cell was completed, using a desktop UV curing device (HCT3B28HEX-1) (manufactured by Senlite). Irradiation was performed, and the voltage holding ratio was measured under the same conditions as described above.

  The value of the voltage holding ratio immediately after the production of the liquid crystal cell was higher, and the evaluation was better as the value after the ultraviolet irradiation was smaller than the value of the voltage holding ratio immediately after the production of the liquid crystal cell (Table 5). And Table 6 shows the values of VHR immediately after the liquid crystal cell was produced and after ultraviolet irradiation).

  Tables 5 and 6 show the results obtained in the examples and comparative examples.

<Example 1>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (1) (3.00 g) obtained by the synthesis method of Synthesis Example 1, and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (3) obtained by the synthesis method of Synthesis Example 3 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (1). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (1), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

<Example 2>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (1) (3.00 g) obtained by the synthesis method of Synthesis Example 1, and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (4) obtained by the synthesis method of Synthesis Example 4 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (2). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (2), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

<Example 3>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (1) (3.00 g) obtained by the synthesis method of Synthesis Example 1, and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (5) obtained by the synthesis method of Synthesis Example 5 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (3). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (3), "evaluation of storage stability of liquid crystal aligning agent", "evaluation of whitening / aggregation of liquid crystal aligning agent" and "evaluation of voltage holding ratio" were performed. .

<Example 4>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (2) (3.00 g) obtained by the synthesis method of Synthesis Example 2, and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (3) obtained by the synthesis method of Synthesis Example 3 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (4). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (4), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

<Example 5>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (2) (3.00 g) obtained by the synthesis method of Synthesis Example 2, and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (4) obtained by the synthesis method of Synthesis Example 4 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (5). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (5), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

<Example 6>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (2) (3.00 g) obtained by the synthesis method of Synthesis Example 2, and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (5) obtained by the synthesis method of Synthesis Example 5 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (6). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (6), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

<Comparative Example 1>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (6) (3.00 g) obtained by the synthesis method of Synthesis Example 6 and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (7) obtained by the synthesis method of Synthesis Example 7 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (7). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (7), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

<Comparative example 2>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (1) (3.00 g) obtained by the synthesis method of Synthesis Example 1, and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (7) obtained by the synthesis method of Synthesis Example 7 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (8). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormality such as turbidity or precipitation.

  Using the obtained liquid crystal aligning agent (8), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

<Comparative Example 3>
NMP (11.0 g) and γ-BL (11.0 g) are added to the polyimide powder (6) (3.00 g) obtained by the synthesis method of Synthesis Example 6 and dissolved by stirring at 50 ° C. for 20 hours. It was. To this solution, NMP (4.00 g), γ-BL (6.00 g), BCS (10.0 g) and DPM (5.00 g) were added and stirred at 50 ° C. for 20 hours to obtain a polymer solution. It was.

  On the other hand, NMP was added to the polyamic acid solution (3) obtained by the synthesis method of Synthesis Example 3 so that the resin solid content concentration was 6% by mass to obtain a polymer solution.

  Then, the said 2 polymer solution was mixed, K1 (0.15g) was added to the solution, and it stirred at 25 degreeC for 20 hours, and obtained the liquid-crystal aligning agent (9). This liquid crystal aligning agent was confirmed to be a uniform solution without any abnormalities such as turbidity and precipitation.

  Using the obtained liquid crystal aligning agent (9), “evaluation of storage stability of liquid crystal aligning agent”, “evaluation of whitening / aggregation of liquid crystal aligning agent” and “evaluation of voltage holding ratio” were performed. .

＊１：すべての重合体１００質量部に対する特定重合体（Ａ）の導入量（質量部）を示す。
＊２：すべての重合体１００質量部に対する特定重合体（Ｂ）の導入量（質量部）を示す。
＊３：すべての溶媒１００質量部に対するその他重合体の導入量（質量部）を示す。

* 1: An introduction amount (parts by mass) of the specific polymer (A) with respect to 100 parts by mass of all polymers.
* 2: Indicates the introduction amount (parts by mass) of the specific polymer (B) with respect to 100 parts by mass of all polymers.
* 3: An introduction amount (parts by mass) of other polymer with respect to 100 parts by mass of all solvents.

＊１：すべての重合体１００質量部に対する特定重合体（Ａ）の導入量（質量部）を示す。
＊２：すべての重合体１００質量部に対する特定重合体（Ｂ）の導入量（質量部）を示す。
＊３：すべての溶媒１００質量部に対するその他重合体の導入量（質量部）を示す。

* 1: An introduction amount (parts by mass) of the specific polymer (A) with respect to 100 parts by mass of all polymers.
* 2: Indicates the amount (parts by mass) of the specific polymer (B) introduced relative to 100 parts by mass of all polymers.
* 3: An introduction amount (parts by mass) of other polymer with respect to 100 parts by mass of all solvents.

  As can be seen from the above results, the liquid crystal aligning agent of the example of the present invention is superior in storage stability of the liquid crystal aligning agent compared to the liquid crystal aligning agent of the comparative example, and the liquid crystal aligning agent is used as the substrate. When applied on the top, whitening and aggregation of the polymer component could be suppressed. In addition, in addition to good initial characteristics, it was possible to suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time.

  Specifically, examples of the liquid crystal aligning agent using the specific polymer (A) and the specific polymer (B) of the present invention, a polymer not containing the specific diamine compound (1) and the specific diamine compound ( It is a comparative example of the liquid crystal aligning agent using the polymer which does not contain 2), ie, a comparison between Example 1 and Comparative Example 1. In this comparative example, turbidity and precipitates are likely to occur during storage of the liquid crystal alignment treatment agent compared to the corresponding examples, and when the liquid crystal alignment treatment agent is applied on the substrate, the polymer component Whitening / aggregation of ash became easier. In addition, regarding the voltage holding ratio, in addition to the value immediately after the production of the liquid crystal cell, the decrease after being exposed to light irradiation for a long time became large.

  Furthermore, with the Example of the liquid-crystal aligning agent using the specific polymer (A) and specific polymer (B) of this invention, and the Example of the liquid-crystal aligning agent which uses only one of them Comparison, that is, comparison between Example 1 and Comparative Example 2 or Comparative Example 3. In these comparative examples, as described above, when the liquid crystal alignment treatment agent is stored, turbidity and precipitates are likely to occur during storage, and when the liquid crystal alignment treatment agent is applied on the substrate, as in the above examples. In addition, whitening and aggregation of the polymer component was likely to occur. In addition, regarding the voltage holding ratio, in addition to the value immediately after the production of the liquid crystal cell, the decrease after being exposed to light irradiation for a long time became large.

  The liquid crystal aligning agent of the present invention is excellent in storage stability of the liquid crystal aligning agent, and when the liquid crystal aligning agent is applied on the substrate, it suppresses whitening / aggregation of the polymer component, and the coating film uniformity. An excellent liquid crystal alignment film can be provided. In addition, in addition to good initial characteristics, the liquid crystal alignment film can suppress a decrease in voltage holding ratio even after being exposed to light irradiation for a long time.

  Therefore, the liquid crystal display element having a liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of the present invention has excellent reliability, and is used for a large-screen high-definition liquid crystal television, a small-sized car navigation system, a smartphone, and the like. It can be suitably used.

Claims (17)

Liquid crystal aligning agent containing the following (A) component and (B) component.
Component (A): a polymer containing at least one selected from polyamic acid having a structure having a nitrogen atom and polyimide, and the structure having the nitrogen atom has the following formulas [1a] to [1c]: It is at least 1 type of structure chosen from the structure shown by these.
(B) Component: A polymer containing at least one selected from polyamic acid and polyimide having a structure represented by the following formula [2].

(In Formula [1a], X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring, X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms; 1b], X ³ and X ⁷ are each independently an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings, and X ⁴ and X ⁶ are each independently , A hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X ⁵ represents an alkylene group or biphenyl group having 2 to ⁵ carbon atoms, m represents an integer of 0 or 1, and in formula [1c], X ⁸ And X ¹⁰ each independently represents at least one structure selected from the structures represented by the following formulas [1c-a] and [1c-b], and X ⁹ represents an alkylene group having 1 to 10 carbon atoms. Or a benzene ring).

(Wherein [2], ^{Y 1} and ^{Y 7} are each independently a single bond, an alkylene group having 1 to 10 carbon ^{atoms, -O -, - N (R} 1) - (R 1 is a hydrogen atom or a carbon atoms 1 to 3 alkyl groups ), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom) Or an alkyl group having 1 to 3 carbon atoms), at least one organic group selected from —CH ₂ O—, —COO— and —OCO—, wherein Y ² and Y ⁶ are each independently carbon An alkylene group having 1 to 10 carbon atoms, Y ³ and Y ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and Y ⁴ represents an oxygen atom or a sulfur atom). The liquid crystal aligning agent according to claim 1, wherein the polymer of the component (A) is a polymer obtained by using a diamine compound represented by the following formula [1-1] as a part of a raw material.

(In Formula [1-1], X ^A represents an organic group having 5 to 50 carbon atoms having at least one structure selected from the structures represented by Formula [1a] to Formula [1c], and A ¹ and A ² each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms). The liquid crystal aligning agent according to claim 2, wherein the diamine compound is a diamine compound represented by the following formulas [1a-1] to [1c-1].

(In the formula [1a-1], X ¹ represents a benzene ring or a nitrogen-containing aromatic heterocyclic ring, X ² represents a hydrogen atom or a disubstituted amino group substituted with an aliphatic group having 1 to 12 carbon atoms, In formula [1b-1], X ³ and X ⁷ each independently represent an aromatic group having 6 to 15 carbon atoms and 1 to 2 benzene rings, and X ⁴ and X ⁶ are Each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, X ⁵ represents an alkylene group or biphenyl group having 2 to ⁵ carbon atoms, m represents an integer of 0 or 1, and the formula [1c- 1], X ⁸ and X ¹⁰ each independently represent at least one structure selected from the structures represented by the formulas [1c-a] and [1c-b], and X ⁹ has 1 carbon atom. To an alkylene group or a benzene ring, represented by formulas [1a-1] to [ 1c-1], A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The liquid crystal aligning agent according to claim 3, wherein the diamine compound is at least one diamine compound selected from diamine compounds represented by the following formulas [1-1a] to [1-4a].

(In the formula [1-3a], R ¹ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. In the formula [1-4a], n represents an integer of 1 to 10, and the formula [1-1a] In Formula [1-4a], A ^{1 to} A ⁸ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The polymer of the said (B) component is a polymer obtained using the diamine compound shown by following formula [2-1] for a part of raw material, As described in any one of Claims 1-4. The liquid crystal aligning agent of description.

(In Formula [2-1], Y ^A represents an organic group having the structure represented by Formula [2], and A ¹ and A ² are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. Showing). The liquid crystal aligning agent according to claim 5, wherein the diamine compound is a diamine compound represented by the following formula [2a].

(In Formula [2a], Y ¹ and Y ⁷ are each independently a single bond, an alkylene group having 1 to 10 carbon atoms, —O—, —N (R ¹ ) — (R ¹ is a hydrogen atom or a carbon number, 1 to 3 alkyl groups ), —CON (R ² ) — (R ² represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms), —N (R ³ ) CO— (R ³ represents a hydrogen atom) Or an alkyl group having 1 to 3 carbon atoms), at least one organic group selected from —CH ₂ O—, —COO— and —OCO—, wherein Y ² and Y ⁶ are each independently carbon an alkylene group having 1 to 10, ^{Y 3} and ^{Y 5} each independently represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, ^{Y 4} represents an oxygen atom or a sulfur atom, ^{a 1} and a ² each independently represent a hydrogen atom or alkyl of 1 to 5 carbon atoms A group). The liquid crystal aligning agent according to claim 6, wherein the diamine compound is at least one diamine compound selected from diamine compounds represented by the following formulas [2-1a] to [2-3a].

(In the formulas [2-1a] to [2-3a], A ^{1 to} A ⁶ each independently represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms). The polymer of the component (A) and the polymer of the component (B) are at least one polymer selected from polyamic acid and polyimide obtained by using a tetracarboxylic acid component represented by the following formula [3]. The liquid-crystal aligning agent as described in any one of Claims 1-7.

(In formula [3], Z represents at least one structure selected from structures represented by formula [3a] to formula [3k] below).

(In the formula [3a], Z ^{1 to} Z ⁴ represent a hydrogen atom, a methyl group, an ethyl group, a propyl group, a chlorine atom or a benzene ring, which may be the same or different, and in the formula [3g] Z ⁵ and Z ⁶ each represent a hydrogen atom or a methyl group, and may be the same or different.   The tetracarboxylic acid component is a tetracarboxylic acid component having at least one structure selected from a structure in which Z in the formula [3] is represented by [3a] and formulas [3e] to [3g]. 8. The liquid crystal aligning agent according to 8.   In the polymer of the component (A), the diamine compound represented by the formula [1a-1] to the formula [1c-1] is 5 mol% to 95 mol% in 100 mol% of all diamine components. The liquid crystal aligning agent as described in any one of Claims 3-9.   The polymer of the said (B) component WHEREIN: The diamine compound shown by the said formula [2a] is 5 mol%-95 mol% in 100 mol% of all the diamine components, Any one of Claims 6-10. The liquid crystal aligning agent according to one item.   The polymer of said (B) component is 0.5 mass part-950 mass parts with respect to 100 mass parts of polymers of said (A) component, It is any one of Claims 1-11. Liquid crystal alignment treatment agent.   The solvent for a liquid crystal aligning agent contains at least one solvent selected from N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and γ-butyrolactone. Liquid crystal aligning agent as described in.   As a solvent for the liquid crystal aligning agent, at least one selected from 1-hexanol, cyclohexanol, 1,2-ethanediol, 1,2-propanediol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether and dipropylene glycol dimethyl ether The liquid-crystal aligning agent as described in any one of Claims 1-13 containing a solvent.   The liquid crystal aligning agent has at least one substituent selected from the group consisting of a crosslinkable compound having an epoxy group, an isocyanate group, an oxetane group or a cyclocarbonate group, a hydroxyl group, a hydroxyalkyl group or a lower alkoxyalkyl group. The liquid-crystal aligning agent as described in any one of Claims 1-14 containing the crosslinkable compound and the at least 1 sort (s) of crosslinkable compound chosen from the crosslinkable compound which has a polymerizable unsaturated bond.   The liquid crystal aligning film obtained from the liquid-crystal aligning agent as described in any one of Claims 1-12 and Claim 15.   The liquid crystal display element which has a liquid crystal aligning film of Claim 16.