Liquid crystal alignment agents, liquid crystal alignment films, liquid crystal elements, polymers and compounds

Abstract

To provide a liquid crystal alignment agent that exhibits good coating properties, and reduces the generation of an afterimage due to accumulation of residual electric charges.SOLUTION: A liquid crystal alignment agent contains one or more polymers (P) selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide. The liquid crystal alignment agent satisfies at least one of a requirement (I) and a requirement (II). Requirement (I): containing a compound including a partial structure (A) and a partial structure (B) in the same molecule. Requirement (II): containing a compound including the partial structure (A) and the partial structure (B) in different molecules. The partial structure (A): at least one selected from the group consisting of a specific substituted heterocyclic structure, a quinone structure, and a tetracyanoquinodimethane structure. The partial structure (B): at least one selected from the group consisting of a partial structure represented by the following formula (b1) and a phenothiazine structure.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to liquid crystal alignment agents, liquid crystal alignment films, liquid crystal elements, polymers, and compounds. [Background technology]

[0002] Liquid crystal elements are used in a wide range of applications, from relatively large display devices such as LCD televisions and information displays to small display devices such as smartphones. The performance of a liquid crystal element is determined by various characteristics such as the orientation of the liquid crystals, the size of the pre-tilt angle, and the voltage retention rate. In order to improve the performance of liquid crystal elements, improvements have been made to the liquid crystal alignment film, which aligns the liquid crystals in a specific direction.

[0003] When voltage is applied to a liquid crystal element, charge accumulates within the liquid crystal cell, which is visible to the observer as an afterimage (DC afterimage), raising concerns about a decrease in the display quality of the liquid crystal element. Therefore, one of the required characteristics of a liquid crystal alignment film is low residual charge accumulation.

[0004] Therefore, various techniques have been proposed to suppress the accumulation of residual charge within liquid crystal cells and improve the display quality of liquid crystal elements (see, for example, Patent Document 1 and Patent Document 2). Patent Document 1 discloses reducing accumulated charge by incorporating a polyamic acid obtained by reacting a diamine compound containing a nitrogen-containing diamine such as N4,N4'-bis(4-aminophenyl)-benzidine with a tetracarboxylic dianhydride into a liquid crystal alignment agent. Patent Document 2 discloses obtaining a liquid crystal alignment film with rapid relaxation of accumulated charge by incorporating a polymer obtained from a diamine having a structure in which a carbazole structure and a benzene ring are bonded by an amino group into a liquid crystal alignment agent. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2008-107811 [Patent Document 2] International Publication No. 2018 / 110354 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] In recent years, large-screen and high-resolution liquid crystal display devices have been widely put into practical use. These applications require even greater display uniformity and less afterimage than before. Therefore, liquid crystal alignment films must be able to be formed using liquid crystal alignment agents that exhibit excellent coatability (printability), and must also have low residual charge accumulation. On the other hand, conventional methods of reducing residual charge accumulation in liquid crystal elements by introducing tertiary amines or nitrogen-containing aromatic heterocycles into the liquid crystal alignment film have become difficult to implement in recent years because the interaction between the functional groups (e.g., carboxyl groups) of the polymer components and the nitrogen-containing compounds causes a decrease in solubility, making it difficult to meet the high coatability requirements of today.

[0007] Furthermore, with the increasing versatility of liquid crystal devices in recent years, there is a growing demand for the development of liquid crystal elements that produce even less afterimages. To suppress afterimages and improve the quality of liquid crystal elements, it is necessary to ensure that charge does not easily accumulate in the liquid crystal cell, and that any accumulated charge is quickly relieved.

[0008] The object of the present invention is to provide a liquid crystal alignment agent that exhibits good coatability and allows for the creation of liquid crystal elements that are less prone to afterimages caused by the accumulation of residual charge. [Means for solving the problem]

[0009] Through diligent research, the inventors discovered that the above problems could be solved by introducing specific structural units into the liquid crystal alignment film, thus completing the present invention. Specifically, the present invention provides the following means.

[0010] <1> Requirements (I) and (II) below; Requirement (I): containing a compound that includes the following partial structure (A) and partial structure (B) within the same molecule, Requirement (II): containing a compound that includes the following partial structure (A) and partial structure (B) within different molecules, A liquid crystal alignment agent that satisfies at least one of the above. Partial structure (A): at least one selected from the group consisting of a substituted heterocyclic structure, a quinone structure, and a tetracyanoquinodimethane structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with an electron-withdrawing group that does not desorb upon heating at a temperature of 230 °C or lower Partial structure (B): at least one selected from the group consisting of the partial structure represented by the following formula (b1) and a phenothiazine structure [Chemical formula] (In formula (b1), X , B 1 and X 2 satisfy the following [i] or [ii]. "*" represents a bond. [i] X 1 is an aromatic ring group. B 1 is -NY 3 - or an aromatic heterocyclic group. X 2 and Y 3 are such that X 2 is an aromatic ring group and Y 3 is a hydrogen atom or a monovalent organic group, or X 2 and Y 3 are combined with each other to form a nitrogen-containing condensed 2 structure together with the nitrogen atom to which X 3 and Y Combined Ring are bonded. However, the nitrogen-containing condensed ring structure has an aromatic ring, and the nitrogen atom in B 1 is bonded to the aromatic ring in the nitrogen-containing condensed ring structure. [ii] B 1 is -NY 3 -. Y 3 is a hydrogen atom or a monovalent organic group. X 1 and X 2 are combined with each other to form X 1 and X 2Nitrogen-containing cells are formed together with the nitrogen atoms to which they are bonded. Combined Ring The structure is shown. However, the nitrogen-containing condensed ring structure has multiple aromatic rings, B 1 The nitrogen atom inside links the two aromatic rings in the nitrogen-containing condensed ring structure.

[0011] <2> The polymer (P) contains at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide, wherein the polymer (P) contains structural units derived from a diamine compound having the substructure (B), <1> The liquid crystal alignment agent described above.

[0012] <3> The polymer (P) contains at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide, wherein the polymer (P) contains the following structural units (UA) and structural units (UB) in the same molecule, or contains the following structural units (UA) and structural units (UB) in different molecules. <1> or <2> The liquid crystal alignment agent described above. Structural unit (UA): A structural unit derived from at least one selected from the group consisting of diamine compounds having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C (DA-1), and diamine compounds having a quinone structure (DA-2). Structural unit (UB): A structural unit derived from at least one selected from the group consisting of a diamine compound having a substructure represented by the above formula (b1) (DB-1) and a diamine compound having a phenothiazine structure (DB-2).

[0013] <4> The aforementioned diamine compound (DA-1) is a compound represented by the following formula (a1-1), as described above. <3> The liquid crystal alignment agent described above. [ka] (In formula (a1-1), A 1This is a group having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are replaced by electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C. 1 Ar is a single bond or a (n1+1) valence linking group. 1 (This is an aromatic ring group. n1 is either 1 or 2.)

[0014] <5> The aforementioned diamine compound (DA-2) is at least one selected from the group consisting of compounds represented by the following formula (a2-1) and compounds represented by the following formula (a2-2). <3> or <4> The liquid crystal alignment agent described above. [ka] (In formula (a2-1), A 2 R is a group that has a quinone structure. 2 Ar is a single bond or a (n²+1) valence linking group. 2 It is an aromatic ring group. n2 is either 1 or 2. In formula (a2-2), A 3 R is a group that has a quinone structure. 3 and R 4 Each of these is independently a single bond or a divalent organic group. 3 and Ar 4 These are each independent aromatic ring groups.

[0015] <6> The aforementioned diamine compound (DB-2) is a compound represented by the following formula (b2-1), as described above. <3> ~ <5> A liquid crystal alignment agent as described in any of the following. [ka] (In formula (b2-1), A 4 R is a group having a phenothiazine structure. 5 Ar is a single bond or a (n3+1) valence linking group. 5 (This is an aromatic ring group. n3 is either 1 or 2.)

[0016] <7> The polymer (P) further comprises structural units (UC) derived from a diamine compound having a substructure represented by the following formula (2), <2> ~ <6> A liquid crystal alignment agent as described in any of the following. [ka] (In formula (2), X 5 and X 6 These are each an independent aromatic ring group. 7 and R 8 Each of these is independently a single bond, an alkanediyl group having 1 to 10 carbon atoms, or a substituted alkanediyl group having 1 to 10 carbon atoms. 5 and Y 6 Each of them is independent of the others, * 4 -NR 9 -CO- or * 4 -CO-NR 9 - is R 9 is a hydrogen atom or a monovalent organic group. 4 " is Z 5 This represents a combination with Z. 5 is a single bond or a divalent organic group. m is 0 or 1. If m is 0, R 7 , R 8 Alternatively, both of these are alkanediyl groups or substituted alkanediyl groups having 1 to 10 carbon atoms. (* indicates a bond.)

[0017] <8> The above-mentioned compound containing the substructure (A) (excluding polymers) and the polymer (P) <2> The liquid crystal alignment agent described above.

[0018] <9> The electron-withdrawing group is at least one selected from the group consisting of a halogen atom, a cyano group, an alkyl halide, and an acyl group. <1> ~ <8> A liquid crystal alignment agent as described in any of the following. <10> The above further contains a polymer (Q) that does not have either the substructure (A) or the substructure (B), <1> ~ <9> A liquid crystal alignment agent as described in any of the following. <11> The polymer (Q) is at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, and addition polymer. <10> The liquid crystal alignment agent described above.

[0019] <12> the above <1> ~ <11> A liquid crystal alignment film formed using any of the liquid crystal alignment agents described in one of the following. <13> the above <12> A liquid crystal element comprising the liquid crystal alignment film described above.

[0020] <14> A polymer comprising a polyamic acid, a polyamic acid ester, or a polyimide, which contains the following structural units (UA) and (UB) within the same molecule. Structural unit (UA): A structural unit derived from at least one selected from the group consisting of diamine compounds having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C (DA-1), and diamine compounds having a quinone structure (DA-2). Structural unit (UB): A structural unit derived from at least one selected from the group consisting of a diamine compound having a substructure represented by the following formula (b1) (DB-1) and a diamine compound having a phenothiazine structure (DB-2). [ka] (In formula (b1), X 1 B 1 and X 2 It satisfies either [i] or [ii] below. [i]X 1 This is an aromatic ring group. 1 is, -NY 3 -or an aromatic heterocyclic group. X 2 and Y 3 X 2 is an aromatic ring group, Y 3 is a hydrogen atom or a monovalent organic group, or X 2 and Y 3 and are combined to form X 2 and Y 3 Nitrogen-containing cells are formed together with the nitrogen atoms to which they are bonded. Combined Ring The structure is shown. However, the nitrogen-containing condensed ring structure has an aromatic ring, B 1 The nitrogen atoms inside are bonded to the aromatic ring in the nitrogen-containing condensed ring structure. [ii]B 1 Ha-NY 3 - is Y 3 X is a hydrogen atom or a monovalent organic group. 1 and X 2 They are combined with each other to form X 1 and X 2 Nitrogen-containing cells are formed together with the nitrogen atoms to which they are bonded. Combined Ring The structure is shown. However, the nitrogen-containing condensed ring structure has multiple aromatic rings, B 1 The nitrogen atom inside links the two aromatic rings in the nitrogen-containing condensed ring structure. The asterisk (*) represents a bonding operation.

[0021] <15> The compound represented by the following formula (a1-1). [ka] (In formula (a1-1), A 1 This refers to a group having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with at least one selected from the group consisting of halogen atoms, cyano groups, alkyl halides, and acyl groups. 1 Ar is a single bond or a (n1+1) valence linking group. 1 (This is an aromatic ring group. n1 is either 1 or 2.)

[0022] <16> The compound represented by the following formula (a2-2). [ka] (In formula (a2-2), A 3 R is a group that has a quinone structure. 3 and R 4 Each of these is independently a single bond or a divalent organic group. 3 and Ar 4 These are each independent aromatic ring groups.

[0023] <17> The compound represented by the following formula (b2-1). [ka] (In formula (b2-1), A 4 R is a group having a phenothiazine structure. 5 Ar is a single bond or a (n3+1) valent saturated chain hydrocarbon group. 5 (This is an aromatic ring group. n3 is either 1 or 2.) [Effects of the Invention]

[0024] According to the liquid crystal alignment agent of the present invention, it is possible to obtain a liquid crystal element that exhibits good coatability, has low residual charge accumulation, and is less prone to afterimages (DC afterimages). [Brief explanation of the drawing]

[0025] [Figure 1] A figure showing the 1H-NMR spectrum of compound (DA-1). [Figure 2] A figure showing the 1H-NMR spectrum of compound (DA-9). [Modes for carrying out the invention]

[0026] Liquid crystal alignment agent The components included in the liquid crystal alignment agent of this disclosure, as well as other components that may be optionally added as needed, are described below.

[0027] In this specification, "hydrocarbon group" includes linear hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. "Linear hydrocarbon group" means a linear hydrocarbon group or a branched hydrocarbon group that does not contain a cyclic structure in its main chain and consists only of a linear structure. However, linear hydrocarbon groups may be saturated or unsaturated. "Alicyclic hydrocarbon group" means a hydrocarbon group that contains only the structure of an alicyclic hydrocarbon as its ring structure and does not contain an aromatic ring structure. However, an alicyclic hydrocarbon group does not have to consist only of the structure of an alicyclic hydrocarbon, and may also include those that have a linear structure as part of it. "Aromatic hydrocarbon group" means a hydrocarbon group that contains an aromatic ring structure as its ring structure. However, an aromatic hydrocarbon group does not have to consist only of an aromatic ring structure, and may include a linear structure or an alicyclic hydrocarbon structure as part of it. "Aromatic ring" means an aromatic hydrocarbon ring and an aromatic heterocycle. "Organic group" means an atomic group obtained by removing any hydrogen atom from a carbon-containing compound (i.e., an organic compound).

[0028] The "main chain" of a polymer refers to the "trunk" portion of the polymer, which consists of the longest chain of atoms. This "trunk" portion may contain a ring structure. For example, "having a specific structure in the main chain" means that the specific structure constitutes a part of the main chain. "Side chains" refer to the parts of a polymer that branch off from the "trunk." "Tetracarboxylic acid derivatives" include tetracarboxylic dianhydrides, tetracarboxylic diesters, and tetracarboxylic diester dihalides.

[0029] The liquid crystal alignment agent of this disclosure is a composition that satisfies at least one of the following requirements (I) and (II). Requirement (I): Contains a compound that includes substructure (A) and substructure (B) within the same molecule. Requirement (II): Contains a compound in which substructure (A) and substructure (B) are contained within different molecules.

[0030] Here, the above partial structure (A) is at least one selected from the group consisting of a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocycle are substituted with an electron-withdrawing group (however, a group that does not desorb by heating at a temperature of 230°C or lower), a quinone structure, and a tetracyanoquinodimethane structure. The above partial structure (B) is at least one selected from the group consisting of a partial structure represented by the following formula (b1) and a phenothiazine structure. [Chemical formula] [[ID=​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0031] If the liquid crystal alignment agent of this disclosure satisfies requirement (I), the compound containing substructure (A) and substructure (B) within the same molecule may be a polymer component or an additive component (i.e., a compound different from the polymer). Furthermore, if the liquid crystal alignment agent of this disclosure satisfies requirement (II), the compound having substructure (A) and the compound having substructure (B) may each be a polymer component or an additive component.

[0032] In terms of the ease of application of the liquid crystal alignment agent and its effect in improving afterimage reduction in liquid crystal elements, the liquid crystal alignment agent of this disclosure preferably contains a polymer (P) which is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide, and the polymer (P) preferably contains structural units derived from a diamine compound having a partial structure (B). Preferred embodiments of the liquid crystal alignment agent of this disclosure include the following embodiments [1] and [2]. Embodiment [1] The polymer (P) contains the following structural unit (UA) and structural unit (UB) within the same molecule, or contains structural unit (UA) and structural unit (UB) within different molecules. Structural unit (UA): A structural unit derived from at least one selected from the group consisting of diamine compounds having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C (DA-1), and diamine compounds having a quinone structure (DA-2). Structural unit (UB): A structural unit derived from at least one selected from the group consisting of a diamine compound having a substructure represented by the above formula (b1) (DB-1) and a diamine compound having a phenothiazine structure (DB-2). Embodiment [2] Contains a compound having a substructure (A) (excluding polymers) and a polymer (P) which is a polymer having a substructure (B).

[0033] The embodiment described in [1] above will be referred to as the first liquid crystal alignment agent, and the embodiment described in [2] above as the second liquid crystal alignment agent. The following will describe each liquid crystal alignment agent.

[0034] <First liquid crystal alignment agent> The first liquid crystal alignment agent contains a polymer (P) which is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide, and which contains specific structural units (structural units (UA) and structural units (UB)) in the same molecule or in different molecules. The polymer (P) contained in the first liquid crystal alignment agent of this disclosure and other optionally blended components will be described in detail below. In this specification, unless otherwise specified, each component may be used alone or in combination of two or more.

[0035] <Polymer (P)> Polymer (P) is a polymer that has structural units derived from a tetracarboxylic acid derivative and structural units derived from a diamine compound within the same molecule. Polymer (P) contains the above structural units (UA) and (UB) as structural units derived from the diamine compound within the same molecule, or contains structural units (UA) and (UB) within different molecules.

[0036] Specific embodiments of the liquid crystal alignment agent containing the polymer (P) include the following embodiments (I) and (II). (I) Contains a polymer (P1) having structural unit (UA) and structural unit (UB) within the same molecule. (II) A polymer (PA) having a structural unit (UA) and a polymer (PB) having a structural unit (UB) (provided that it is a polymer different from polymer (PA)) are contained. Of these, the embodiment (I) containing polymer (P1) is preferred because it allows for a sufficient reduction in DC afterimage while minimizing the components of the liquid crystal alignment agent. Note that diamine compounds (DA-1), (DA-2), (DB-1), and (DB-2) are all different compounds. Below, structural units (UA) and (UB) will be explained first.

[0037] [About structural units (UA)] A structural unit (UA) is derived from at least one selected from the group consisting of diamine compounds (DA-1) having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with electron-withdrawing groups (hereinafter also referred to as "electron-withdrawing group F1") that do not leave the ring when heated at temperatures below 230°C, and diamine compounds (DA-2) having a quinone structure. Both diamine compounds (DA-1) and diamine compounds (DA-2) are compounds that exhibit electron-accepting properties when used in combination with one or more selected from the group consisting of diamine compounds (DB-1) and diamine compounds (DB-2).

[0038] • Diamine compound (DA-1) The substituted heterocyclic structure of the diamine compound (DA-1) has a structure in which an electron-withdrawing group F1 is bonded to a nitrogen-containing aromatic heterocyclic ring. The nitrogen-containing aromatic heterocyclic ring to which the electron-withdrawing group F1 is bonded may be a monocyclic ring or a fused ring. Specific examples of the nitrogen-containing aromatic heterocyclic ring include a pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyrimidine ring, pyridazine ring, pyrazine ring, quinoline ring, isoquinoline ring, benzimidazole ring, indazole ring, acridine ring, etc. Of these, the nitrogen-containing aromatic heterocyclic ring to which the electron-withdrawing group F1 is bonded is preferably a pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyrimidine ring, pyridazine ring, or pyrazine ring, more preferably an imidazole ring, pyridine ring, pyrimidine ring, pyridazine ring, or pyrazine ring, and even more preferably an imidazole ring.

[0039] The electron-withdrawing group F1 is not particularly limited, as long as it is an electron-withdrawing group that does not leave the system when heated at temperatures below 230°C. For example, the electron-withdrawing group F1 is a group that does not leave the system even when heated at temperatures above 100°C. The electron-withdrawing group F1 is preferably at least one selected from the group consisting of halogen atoms, cyano groups, alkyl halides, and acyl groups. Here, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, iodine atoms, etc. Examples of alkyl halides include groups in which one or more hydrogen atoms of a linear or branched alkyl group having 1 to 10 carbon atoms are substituted with halogen atoms. Of these, alkyl halides having 1 to 6 carbon atoms are preferred, groups having 1 to 3 carbon atoms are more preferred, perfluoroalkyl groups having 1 to 3 carbon atoms are even more preferred, and trifluoromethyl groups are particularly preferred. The acyl group preferably has a structure in which a monovalent hydrocarbon group having 1 to 6 carbon atoms is bonded to a carbonyl group. In the acyl group, the hydrocarbon group bonded to the carbonyl group is more preferably an alkyl group having 1 to 3 carbon atoms, and even more preferably a methyl group or an ethyl group.

[0040] In the substituted heterocyclic structure of the diamine compound (DA-1), the number of electron-withdrawing groups F1 bonded to the nitrogen-containing aromatic heterocycle is not particularly limited. The number of electron-withdrawing groups F1 bonded to each nitrogen-containing aromatic heterocycle is, for example, 1 to 4, preferably 1 to 3, and more preferably 1 or 2.

[0041] The electron-withdrawing group F1 is preferably at least one selected from the group consisting of a halogen atom, a cyano group, a C1-C3 alkyl halide, and an acyl group, in order to further enhance the DC afterimage reduction effect. It is more preferably a cyano group or an acyl group, and particularly preferably a cyano group.

[0042] The diamine compound (DA-1) may have only one substituted heterocyclic structure, or it may have two or more. From the viewpoint of improving the solubility of the polymer (P) and ensuring the coatability of the liquid crystal alignment agent, the number of substituted heterocyclic structures in the diamine compound (DA-1) is preferably 1 to 3, and more preferably 1 or 2.

[0043] The diamine compound (DA-1) is preferably a compound represented by the following formula (a1-1). [ka] (In formula (a1-1), A 1 This is a group having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are replaced by electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C. 1 Ar is a single bond or a (n1+1) valence linking group. 1 (This is an aromatic ring group. n1 is either 1 or 2.)

[0044] In equation (a1-1), A 1 The above description applies to specific and preferred examples of the substituted heterocyclic structure, nitrogen-containing aromatic heterocyclic ring, and electron-withdrawing group F1 possessed by the compound.

[0045] If n1 is 1, R 1 The (n1+1) valence linking groups represented by -O-, -CO-, * 1 -O-CO-, * 1 -CO-O-, * 1 -NR 11 -CO-, * 1 -CO-NR 11 - The alkanediyl group having 1 to 4 carbon atoms, and any methylene group having 2 to 4 carbon atoms, are -O-, -CO-, -CO-O-, or -NR 11 A divalent group (R) is formed by replacing -CO-. 11 * is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. 1 " is Ar 1 Examples include (representing a coupling with) and so on.

[0046] If n1 is 2, R 1 The (n1+1) valency linking group represented by is a trivalent saturated chain hydrocarbon group having 1 to 4 carbon atoms, and any methylene group on a trivalent saturated chain hydrocarbon group having 2 to 4 carbon atoms is -O-, -CO-, -CO-O-, or -NR 11 A trivalent group formed by replacing -CO-, * 1 -N(-R 12 -)2(R 11 and "* 1 " is synonymous with the above, R 12 The alkanediyl group having 1 to 4 carbon atoms or any methylene group having 2 to 4 carbon atoms is -O-, -CO-, -CO-O-, or -NR 11 Examples include divalent groups that are replaced by -CO-.

[0047] In terms of being able to further reduce DC afterimages, R 1 It is preferable that the above is a (n1+1) valence linking group, and A 1 It is more preferable that the group is bonded to the nitrogen-containing aromatic heterocycle of the compound via an alkanediyl group. 1 However, A 1 If R is a group that is bonded to a nitrogen-containing aromatic heterocycle by an alkanediyl group, 1 Ar 1 It may be bonded to it by an alkanediyl group, such as -O-, -CO-, -CO-O-, or -NR 11 They may be joined with -CO-.

[0048] Ar 1 The aromatic ring group represented by has p hydrogen atoms from the ring portion of the aromatic ring (where p is R 1 The value is (n1+2) when it is a single bond, and R 1The group that has been removed (the value is 3 when it is not a single bond). Examples of aromatic rings that the aromatic ring group has include aromatic hydrocarbon rings such as benzene rings, naphthalene rings, and anthracene rings; and nitrogen-containing aromatic heterocycles such as pyrrole rings, imidazole rings, pyrazole rings, pyridine rings, pyrimidine rings, pyridazine rings, pyrazine rings, quinoline rings, isoquinoline rings, and benzimidazole rings. Among these, Ar 1 The aromatic ring of the aromatic ring group represented by is preferably a benzene ring, a naphthalene ring, a pyridine ring, or a pyrimidine ring, with a benzene ring being more preferred. 1 The aromatic ring group represented by may have substituents on the aromatic ring portion in addition to the two primary amino groups. Examples of such substituents include alkyl groups having 1 to 3 carbon atoms, halogen atoms, and the like.

[0049] Ar 1 The aromatic ring group represented by has two primary amino groups attached to its aromatic ring. The positions of these primary amino groups are not particularly limited. For example, Ar 1 When the aromatic ring group represented by has a benzene ring, the bonding positions of the two primary amino groups are those of other groups (R 1 For the above, the 2nd, 4th, 2nd, 5th, or 3rd, 5th positions are mentioned.

[0050] Specific examples of diamine compounds (DA-1) include the compounds represented by the following formulas (d-1-1) to (d-1-16). [ka] [ka] [ka]

[0051] When the polymer (P) contains structural units derived from the diamine compound (DA-1), the proportion of structural units derived from the diamine compound (DA-1) is preferably 2 mol% or more, and more preferably 5 mol% or more, relative to the total structural units derived from the diamine compound constituting the polymer (P). Furthermore, the proportion of structural units derived from the diamine compound (DA-1) is preferably 95 mol% or less, and more preferably 90 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0052] Furthermore, if the first liquid crystal alignment agent contains two or more polymers (P), the proportion of structural units derived from the diamine compound (DA-1) refers to the ratio of all structural units derived from the diamine compound (DA-1) contained in the two or more polymers (P) to the total structural units derived from the diamine compounds constituting the two or more polymers (P). For example, if the first liquid crystal alignment agent contains a first polymer and a second polymer as polymers (P), the proportion of structural units derived from the diamine compound (DA-1) refers to the ratio of the total amount of structural units derived from the diamine compound (DA-1) constituting the first polymer and the total amount of structural units derived from the diamine compound (DA-1) constituting the second polymer to the total amount of structural units derived from the diamine compound (DA-1) constituting the first polymer and the diamine compound (DA-1) constituting the second polymer (the same applies to the following structural units).

[0053] • Diamine compound (DA-2) Diamine compounds (DA-2) are compounds having a quinone structure in their main chain or side chain. Specifically, diamine compounds (DA-2) are preferably at least one selected from the group consisting of compounds represented by the following formula (a2-1) and compounds represented by the following formula (a2-2). [ka] (In formula (a2-1), A 2 R is a group that has a quinone structure. 2 Ar is a single bond or a (n²+1) valence linking group. 2It is an aromatic ring group. n2 is either 1 or 2. In formula (a2-2), A 3 R is a group that has a quinone structure. 3 and R 4 Each of these is independently a single bond or a divalent organic group. 3 and Ar 4 These are each independent aromatic ring groups.

[0054] Examples of quinone structures that the diamine compound (DA-2) may possess include a benzoquinone structure and a naphthoquinone structure. Of these, the benzoquinone structure is preferred for the quinone structure of the diamine compound (DA-2).

[0055] In equation (a2-1), A 2 It is preferable that the group is represented by the following formula (r-1). [ka] (In formula (r-1), R 21 , R 22 and R 23 Each of these is independently a hydrogen atom, a C1-C3 alkyl group, or a C1-C3 alkoxy group. 24 and R 25 Each of these is independently either a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. a is either 0 or 1. "*" represents a bond.

[0056] In equation (r-1), R 21 , R 22 and R 23 A hydrogen atom, a methyl group, or a methoxy group is preferred. 24 and R 25 A hydrogen atom or a methyl group is preferred.

[0057] If n2 is 1, R 2 The (n2+1) valent linking group represented by this is an alkanediyl group having 1 to 3 carbon atoms, with -O-, -CO-, -CO-O-, or -NR between the carbon-carbon bonds of the alkanediyl group. 14 -CO- containing a divalent group with 2 to 4 carbon atoms (R14 Examples include a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. When n2 is 2, R 2 Examples of (n²+1) valent linking groups represented by this expression include trivalent saturated chain hydrocarbon groups having 1 to 4 carbon atoms.

[0058] Ar 2 For specific and preferred examples of aromatic ring groups represented by formula (a1-1), see Ar 1 The explanation applies. n2 is preferably 1.

[0059] In equation (a2-2), A 2 It is preferable that the group is represented by the following formula (r-2). [ka] (In formula (r-2), R 26 and R 27 Each of these is independently a hydrogen atom, a C1-C3 alkyl group, or a C1-C3 alkoxy group. 28 and R 29 Each of these is independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. a1 and a2 are independently 0 or 1. (* represents a bond.)

[0060] In equation (r-2), R 26 and R 27 A hydrogen atom, a methyl group, or a methoxy group is preferred. 28 and R 29 A hydrogen atom or a methyl group is preferred. From the viewpoint of ease of synthesis of the compound represented by formula (a2-2), a1 and a2 are preferably 1.

[0061] In formula (a2-2), R 3 and R 4 The divalent organic group represented by is an alkanediyl group having 1 to 12 carbon atoms, or an alkanediyl group having 2 to 12 carbon atoms, in which one or more methylene groups are -O-, -CO-, -CO-O-, or -NR. 16 -CO-(R 16Examples include divalent groups in which ( is replaced by a hydrogen atom or an alkyl group having 1 to 3 carbon atoms). 3 and R 4 The alkanediyl group of the divalent organic group represented by is preferably linear in order to obtain a liquid crystal alignment film that exhibits good liquid crystal alignment properties. 3 and R 4 The divalent organic group represented by preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 3 carbon atoms.

[0062] Ar 3 and Ar 4 The aromatic ring group represented by is a group obtained by removing two arbitrary hydrogen atoms from the ring portion of an aromatic ring. The aromatic ring possessed by this aromatic ring group is Ar in formula (a1-1). 1 Examples include aromatic hydrocarbon rings and nitrogen-containing aromatic heterocycles, as illustrated in the explanation. 2 The aromatic ring present is preferably a benzene ring, a naphthalene ring, a pyridine ring, or a pyrimidine ring, with a benzene ring being more preferred. Also, Ar 3 and Ar 4 The aromatic ring group represented by may have substituents on the aromatic ring portion in addition to the primary amino group. Examples of such substituents include alkyl groups having 1 to 3 carbon atoms, halogen atoms, and the like.

[0063] Specific examples of diamine compounds (DA-2) include the compounds represented by the following formulas (d-2-1) to (d-2-9). [ka]

[0064] Diamine compound (DA-2) can enhance the effect of mitigating residual charge and reducing charge accumulation when used in combination with at least one selected from the group consisting of diamine compound (DB-1) and diamine compound (DB-2). Among these, compounds having a quinone structure in the main chain are preferred, and the compound represented by formula (a2-2) is more preferred. Specifically, compounds represented by formulas (d-2-1) to (d-2-3) and (d-2-7) can be preferably used.

[0065] When the polymer (P) contains structural units derived from the diamine compound (DA-2), the proportion of structural units derived from the diamine compound (DA-2) is preferably 2 mol% or more, and more preferably 5 mol% or more, relative to the total structural units derived from the diamine compound constituting the polymer (P). Furthermore, the proportion of structural units derived from the diamine compound (DA-2) is preferably 95 mol% or less, and more preferably 90 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0066] The proportion of structural units (UA) in the polymer (P) is preferably 5 mol% or more, and more preferably 10 mol% or more, relative to the total structural units derived from the diamine compound constituting the polymer (P). Furthermore, the proportion of structural units (UA) is preferably 95 mol% or less, and more preferably 90 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0067] [About Structural Units (UB)] The structural unit (UB) is derived from at least one selected from the group consisting of a diamine compound (DB-1) having a substructure represented by the above formula (b1) and a diamine compound (DB-2) having a phenothiazine structure. Both diamine compounds (DB-1) and (DB-2) are compounds that exhibit electron-donating properties when used in combination with one or more selected from the group consisting of diamine compounds (DA-1) and (DA-2). Note that diamine compound (DB-1) is a compound that does not have a phenothiazine structure, and in this respect, it differs from diamine compound (DB-2).

[0068] • Diamine compound (DB-1) In equation (b1), X 1 and X 2 Examples of aromatic ring groups represented by include divalent aromatic hydrocarbon groups and divalent aromatic heterocyclic groups. Examples of divalent aromatic heterocyclic groups include nitrogen-containing aromatic heterocyclic groups, oxygen-containing aromatic heterocyclic groups, sulfur-containing aromatic heterocyclic groups, etc., with nitrogen-containing aromatic heterocyclic groups being preferred. 1 and X 2 The aromatic ring group represented by may have substituents on the ring portion. Examples of such substituents include alkyl groups having 1 to 5 carbon atoms, halogen atoms, and the like.

[0069] X 1 , X 2 Specific examples include, as a divalent aromatic hydrocarbon group, a group obtained by removing any two hydrogen atoms bonded to carbon atoms constituting a benzene ring, naphthalene ring, or anthracene ring; as a divalent nitrogen-containing aromatic heterocyclic group, a group obtained by removing any two hydrogen atoms bonded to carbon atoms constituting a pyridine ring, pyrimidine ring, pyridazine ring, or pyrazine ring; as a divalent oxygen-containing aromatic heterocyclic group, a group obtained by removing any two hydrogen atoms bonded to carbon atoms constituting a furan ring; and as a divalent sulfur-containing aromatic heterocyclic group, a group obtained by removing any two hydrogen atoms bonded to carbon atoms constituting a thiophene ring. From the viewpoint of increasing the density of the liquid crystal alignment film, X 1and X 2 The aromatic ring group represented is preferably a divalent aromatic hydrocarbon group or a divalent nitrogen-containing aromatic heterocyclic group, more preferably a divalent aromatic hydrocarbon group, and even more preferably a phenylene group.

[0070] B 1 If it is an aromatic heterocyclic group, then the aromatic heterocyclic group is X 1 , X 2 Examples of divalent aromatic heterocyclic groups are given in the explanation. Of these, B 1 The aromatic heterocyclic group represented by is preferably a group obtained by removing any two hydrogen atoms bonded to carbon atoms constituting a pyrrole ring, furan ring, or thiophene ring, in order to enhance the effect of relaxing accumulated charge.

[0071] B 1 ga-NY 3 -If Y 3 The monovalent organic group represented by is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a group that is eliminated by heat to produce a hydrogen atom (hereinafter also referred to as a "thermally detachable group"). 3 If the group is a monovalent hydrocarbon group, the monovalent hydrocarbon group is preferably an alkyl group having 1 to 3 carbon atoms or a phenyl group, and more preferably an alkyl group having 1 to 3 carbon atoms.

[0072] Y 3 If Y is a thermally leaving group, 3Examples of such groups include carbamate-based thermally detachable groups, amide-based thermally detachable groups, imide-based thermally detachable groups, and sulfonamide-based thermally detachable groups. Of these, carbamate-based thermally detachable groups are preferred due to their high thermal detachability. Specific examples include tert-butoxycarbonyl group, benzyloxycarbonyl group, 1,1-dimethyl-2-haloethyloxycarbonyl group, allyloxycarbonyl group, 2-(trimethylsilyl)ethoxycarbonyl group, 9-fluorenylmethyloxycarbonyl group, and allyloxycarbonyl group. Among these, tert-butoxycarbonyl group (Boc group) is particularly preferred due to its excellent thermal detachability and the ability to reduce the amount of residue remaining in the film after deprotection.

[0073] Y 3 Of the above, a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a thermally desorbable group is preferred, and a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a tert-butoxycarbonyl group is more preferred.

[0074] X 1 B 1 and X 2 The above [i] is satisfied, and X 2 and Y 3 However, when combined with each other, X 2 and Y 3 Nitrogen-containing cells are formed together with the nitrogen atoms to which they are bonded. Combined Ring When describing the structure, the contraction Combined Ring Examples of structures include indoline structures, isoindoline structures, indole structures, 1,2,3,4-tetrahydroquinoline structures, 1,2-dihydroquinoline structures, 1,2-dihydroisoquinoline structures, and carbazole structures. 2 and Y 3 When these are combined with each other to form a nitrogen-containing condensed ring structure, B 1 The nitrogen atom inside is bonded by a single bond to the aromatic ring in the nitrogen-containing condensed ring structure.

[0075] X 1 B 1 and X 2 If the above [ii] is satisfied, X 1and X 2 However, when combined with each other, X 1 and X 2 Nitrogen-containing cells are formed together with the nitrogen atoms to which they are bonded. Combined Ring When describing the structure, the nitrogen content shrinkage Combined Ring The structure is preferably a carbazole structure. Specific examples of a carbazole structure include a structure obtained by removing any two hydrogen atoms from the ring portion of a 9H-carbazole ring or an N-substituted carbazole ring. Examples of N-substituted carbazole rings include 9-methylcarbazole and 9-ethylcarbazole.

[0076] A preferred specific example of the substructure represented by the above formula (b1) is X 1 B 1 and X 2 If the above [i] is satisfied, then the substructures etc. represented by each of the following equations (3-1) to (3-10) are X 1 B 1 and X 2 Examples of cases where the above [ii] is satisfied include the substructure represented by the following formula (3-11). From the viewpoint of obtaining a liquid crystal element in which residual charge accumulation is small and DC afterimages are less likely to occur, it is preferable that the polymer (P) has the substructure represented by the above formula (b1) in the main chain of the polymer (P). [ka] (In formulas (3-1) to (3-11), Y 3 and Y 4 Each of these is either a hydrogen atom or a monovalent organic group. (* represents a bond.)

[0077] The diamine compound (DB-1) may have only one substructure represented by formula (b1), or it may have two or more. If the diamine compound (DB-1) has two or more substructures represented by formula (b1), the number of substructures represented by formula (b1) in the diamine compound (DB-1) represents the total number. From the viewpoint of ensuring the solubility of the polymer (P), the total number of substructures represented by formula (b1) is preferably one or two per molecule of the diamine compound (DB-1). The diamine compound (DB-1) is preferably an aromatic diamine, and among these, it is preferably an aromatic diamine having a structure that allows the substructure represented by formula (b1) to be introduced into the main chain of the polymer (P).

[0078] Furthermore, "aromatic diamine" refers to a diamine in which two primary amino groups are bonded to the same or different aromatic rings within the molecule. In aromatic diamines, the aromatic ring to which the two primary amino groups are bonded may be a monoring or a fused ring. When the primary amino groups of an aromatic diamine are bonded to a fused ring, the primary amino groups in the aromatic diamine only need to be bonded to the aromatic rings constituting the fused ring, and the monoring sharing one side with the aromatic ring to which the primary amino groups are bonded may be an aromatic ring or an aliphatic ring.

[0079] Specific examples of diamine compounds (DB-1) include the compounds represented by formulas (d-3-1) to (d-3-22) below. [ka] [ka] [ka]

[0080] When the polymer (P) contains structural units derived from the diamine compound (DB-1), the proportion of structural units derived from the diamine compound (DB-1) is preferably 2 mol% or more, and more preferably 5 mol% or more, relative to the total structural units derived from the diamine compound constituting the polymer (P). Furthermore, the proportion of structural units derived from the diamine compound (DB-1) is preferably 90 mol% or less, and more preferably 80 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0081] • Diamine compound (DB-2) The diamine compound (DB-2) is a compound having a phenothiazine structure. Preferably, the diamine compound (DB-2) is a compound in which the phenothiazine structure can be introduced into the side chain of the polymer (P). Specifically, a compound represented by the following formula (b2-1) is preferably used. [ka] (In formula (b2-1), A 4 R is a group having a phenothiazine structure. 5 Ar is a single bond or a (n3+1) valence linking group. 5 (This is an aromatic ring group. n3 is either 1 or 2.)

[0082] In equation (b2-1), A 4 Preferably, this is a group obtained by removing one hydrogen atom bonded to a carbon or nitrogen atom constituting the ring structure represented by the following formula (r-3). [ka] (In formula (r-3), R 31 and R 32 Each of these is an alkyl group having 1 to 3 carbon atoms. Each of these is an integer from 0 to 4. If b1 is 2 or more, multiple R 31 They are the same or different. If b2 is 2 or more, multiple R 32 They are either the same or different.

[0083] If n3 in equation (b2-1) is 1, R 5 The (n3+1) valency linking groups represented by -O-, -CO-, * 3 -O-CO-, * 3 -CO-O-, * 3 -NR 17 -CO-, * 3 -CO-NR 17 - Any methylene group in an alkanediyl group having 1 to 4 carbon atoms or an alkanediyl group having 2 to 4 carbon atoms is -O-, -CO-, -CO-O-, or -NR 17 A divalent group (R) is formed by substitution with -CO-. 17 * is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. 3 " is Ar 5 Examples include (representing a coupling with) and so on.

[0084] If n3 is 2, R 5 The (n3+1) valent linking group represented by is a trivalent saturated chain hydrocarbon group having 1 to 4 carbon atoms, and any methylene group in a trivalent saturated chain hydrocarbon group having 2 to 4 carbon atoms is -O-, -CO-, -CO-O-, or -NR 17 A trivalent group formed by replacing -CO-, * 3 -N(-R 17 -)2(R 17 and "* 3 Examples include (which is synonymous with the above).

[0085] R 5 It is preferable that the linking group is of (n3+1) valency, as it has a high effect in reducing DC afterimages, and more preferably that it is a group that is bonded to the nitrogen atom in formula (r-3) (i.e., the nitrogen atom constituting the ring portion of the phenothiazine ring) by an alkanediyl group.

[0086] Ar 3 For specific and preferred examples of aromatic ring groups represented by formula (a1-1), see Ar 1 The explanation applies. n3 is preferably 1.

[0087] Specific examples of diamine compounds (DB-2) include the compounds represented by the following formulas (d-4-1) to (d-4-6). [ka]

[0088] When the polymer (P) contains structural units derived from the diamine compound (DB-2), the proportion of structural units derived from the diamine compound (DB-2) is preferably 2 mol% or more, and more preferably 5 mol% or more, relative to the total structural units derived from the diamine compound constituting the polymer (P). Furthermore, the proportion of structural units derived from the diamine compound (DB-2) is preferably 90 mol% or less, and more preferably 80 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0089] The proportion of structural units (UB) in the polymer (P) is preferably 2 mol% or more, and more preferably 5 mol% or more, relative to the total structural units derived from the diamine compound constituting the polymer (P). Furthermore, the proportion of structural units (UB) is preferably 90 mol% or less, and more preferably 85 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0090] From the viewpoint of sufficiently increasing the ability to relax residual charge accumulated by the application of a DC voltage in the resulting liquid crystal alignment film and sufficiently reducing DC afterimages, the ratio of structural units (UB) to structural units (UA) is preferably 0.05 to 9.0 moles. From the above viewpoint, the ratio of structural units (UB) to structural units (UA) is more preferably 0.10 to 5.0 moles, and even more preferably 0.12 to 3.5 moles.

[0091] [Other structural units] Polymer (P) may further contain structural units different from structural units (UA) and structural unit (UB) (hereinafter also referred to as "other structural units") as structural units derived from the diamine compound. Other structural units may be present in polymer (P1), polymer (PA), or polymer (PB), and may be present in two or more of these.

[0092] • Structural Unit (UC) The polymer (P) preferably further contains structural units (UC) derived from a diamine compound having a substructure represented by the following formula (2). By further including structural units (UC) in the polymer (P), the DC afterimage reduction effect can be further enhanced. [ka] (In formula (2), X 5 and X 6 These are each independently divalent aromatic ring groups. 7 and R 8 Each of these is independently a single bond, an alkanediyl group having 1 to 10 carbon atoms, or a substituted alkanediyl group having 1 to 10 carbon atoms. 5 and Y 6 Each of them is independent of the others, * 4 -NR 9 -CO- or * 4 -CO-NR 9 - is R 9 is a hydrogen atom or a monovalent organic group. 4 " is Z 5 This represents a combination with Z. 5 is a single bond or a divalent organic group. m is 0 or 1. If m is 0, R 7 , R 8 Alternatively, both of these are alkanediyl groups or substituted alkanediyl groups having 1 to 10 carbon atoms. (* indicates a bond.)

[0093] In equation (2), X 5 and X 6 The divalent aromatic ring group is preferably an aromatic hydrocarbon group. 5 , X 6Specific examples include groups formed by removing any two hydrogen atoms bonded to carbon atoms constituting an aromatic hydrocarbon ring such as a benzene ring, naphthalene ring, or anthracene ring. 5 and X 6 From the viewpoint of increasing the density of the liquid crystal alignment film, it is preferable that the aromatic ring possessed by X does not have substituents. 5 and X 6 Among these, the phenylene group is preferred, and the 1,4-phenylene group is particularly preferred.

[0094] R 7 and R 8 If is a substituted or unsubstituted alkanediyl group having 1 to 10 carbon atoms, then R 7 and R 8 It is preferable that the liquid crystal alignment is high and that the afterimage reduction effect is high. 7 and R 8 When is a substituted alkanediyl group, examples of substituents include halogen atoms, hydroxyl groups, amino groups, cyano groups, alkoxy groups, protected hydroxyl groups, protected amino groups, etc. 7 and R 8 Preferably, one or both of these are substituted or unsubstituted alkanediyl groups having 1 to 10 carbon atoms, R 7 and R 8 It is more preferable that both are substituted or unsubstituted alkanediyl groups having 1 to 10 carbon atoms.

[0095] Y 5 and Y 6 is an amide bond (* 4 -NR 9 -CO- or * 4 -CO-NR 9 -) R 9 The monovalent organic group represented is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms or a thermally desorbable group. 9 If the group is a monovalent hydrocarbon group, the monovalent hydrocarbon group is preferably an alkyl group having 1 to 3 carbon atoms or a phenyl group, and more preferably an alkyl group having 1 to 3 carbon atoms.

[0096] R9 If R is a thermally leaving group, 9 As for Y in equation (b1), 3 Examples of thermally desorbable groups include the groups shown. They exhibit excellent thermal desorption properties and can reduce the amount of residue remaining in the film of the deprotected portion, R 9 The thermally detachable group represented is preferably a tert-butoxycarbonyl group (Boc group).

[0097] R 9 Among these, hydrogen atoms, C1-C3 alkyl groups, or thermally detachable groups are preferred, and hydrogen atoms, C1-C3 alkyl groups, or tert-butoxycarbonyl groups are more preferred.

[0098] Z 5 Z is a single bond or a divalent organic group. In terms of being able to improve the voltage holding characteristics and liquid crystal alignment of liquid crystal elements, 5 It is preferable that the group is a divalent organic group. The divalent organic group may be a divalent hydrocarbon group having 1 to 20 carbon atoms, with -O-, -S-, or -NR between the carbon-carbon bonds of the hydrocarbon group. 9 -(However, R 9 Y 5 and Y 6 R inside 9 Examples include divalent groups having the same meaning as (and Z). 5 Y 5 and Y 6 It is bonded to the amide bond by a hydrocarbon group.

[0099] In terms of being able to increase the solubility of polymer (P), Z 5 The divalent organic groups represented by are, among these, divalent linear hydrocarbon groups having 1 to 20 carbon atoms, divalent alicyclic hydrocarbon groups having 4 to 20 carbon atoms, or -O-, -S-, or -NR between the carbon-carbon bonds of linear hydrocarbon groups. 9 It is preferably a divalent group having -, and a C1-C20 alkanediyl group or a C4-C12 cycloalkylene group is particularly preferred. 5 The number of carbon atoms is preferably 1 to 12, and more preferably 1 to 10. m is 0 or 1, and is preferably 1.

[0100] The diamine compound that provides the structural unit (UC) (hereinafter also referred to as "diamine compound (C)") is preferably an aromatic diamine, and among these, it is preferably an aromatic diamine having a structure that allows the substructure represented by the above formula (2) to be introduced into the main chain of the polymer (P).

[0101] Specific examples of diamine compounds (C) include the compounds represented by formulas (d-5-1) to (d-5-24) below. [ka] [ka] [ka] (In the formula, "Boc" represents a tert-butoxycarbonyl group.)

[0102] When the polymer (P) contains structural units (UC), the proportion of structural units (UC) is preferably 2 mol% or more, and more preferably 5 mol% or more, relative to the total structural units derived from the diamine compound constituting the polymer (P). Furthermore, the proportion of structural units (UC) is preferably 50 mol% or less, and more preferably 40 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0103] In order to enhance the improvement effect of DC afterimage characteristics, it is preferable that the structural unit (UC) is introduced into the same polymer together with structural unit (UA) and structural unit (UB). That is, it is preferable that the liquid crystal alignment agent of this disclosure includes a polymer (P) having structural unit (UA), structural unit (UB), and structural unit (UC) in a single molecule.

[0104] The polymer (P) may contain, as other structural units, a structural unit (UD) that does not have the partial structure represented by the above formula (2). Examples of the diamine compound constituting the structural unit (UD) include aliphatic diamines, aromatic diamines, diaminoorganosiloxanes, etc. Examples of the aliphatic diamine include chain diamines and alicyclic diamines.

[0105] Specific examples of these diamine compounds include, as chain diamines, metaxylylenediamine, hexamethylenediamine, etc.; as alicyclic diamines, 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), etc.; as aromatic diamines, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4-aminophenyl-4-aminobenzoate, 4,4'-diaminoazobenzene, 3,5-diaminobenzoic acid, 1,5-bis(4-aminophenoxy)pentane, 1,2-bis(4-aminophenoxy)ethane, 1,3-bis(4-aminophenoxy)propane, 1,6-bis(4-aminophenoxy)hexane, 6,6'-(pentamethylenedioxy)bis(3-aminopyridine), N,N'-di(5-amino-2-pyridyl)-N,N'-di(tert-butoxycarbonyl)ethylenediamine, bis[2-(4-aminophenyl)ethyl]hexanedioic acid, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenethylurea, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-(phenylenediisopropylidene)bisaniline, 2,6-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, N4,N4'-bis(4-aminophenyl)-N4,N4'-dimethylbenzidine, N,N'-bis(5-aminopyridin-2-yl)-N,N'-di(tert-butoxycarbonyl)ethylenediamine and other main-chain type diamines; Hexadecanoxy-2,4-diaminobenzene, octadecanoxy-2,4-diaminobenzene, octadecanoxy-2,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholestanyl 3,5-diaminobenzoate, cholesteryl 3,5-diaminobenzoate, lanostanyl 3,5-diaminobenzoate, 3,6-bis(4-aminobenzoyloxy)cholestane, 3,6-bis(4-aminophenoxy)cholestane, 4-(4'-trifluoromethoxybenzoyloxy)cyclohexyl 3,5-diaminobenzoate, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane, cholestan-3-yl 3,5-diaminobenzoate, the following formula (E-1) [Chemical formula] (In formula (E-1), X I and X II are each independently a single bond, -O-, *-COO- or *-OCO- (where "*" represents a bond to the diamino phenyl group side). R I is an alkanediyl group having 1 to 3 carbon atoms. R II is a single bond or an alkanediyl group having 1 to 3 carbon atoms. R III is an alkyl group, an alkoxy group, a fluoroalkyl group, or a fluoroalkoxy group having 1 to 20 carbon atoms. a is 0 or 1. b is an integer from 0 to 3. c is an integer from 0 to 2. d is 0 or 1. However, 1 ≤ a + b + c ≤ 3.) Side-chain diamines such as the compound represented by As the diaminoorganosiloxane, 1,3-bis(3-aminopropyl)-tetramethyldisiloxane and the like can be respectively mentioned.

[0106] Examples of the compound represented by formula (E-1) include compounds represented by each of the following formula (E-1-1) to formula (E-1-4). [ka]

[0107] When the polymer (P) contains structural units (UD), the proportion of structural units (UD) is preferably 65 mol% or less, and more preferably 55 mol% or less, relative to the total structural units derived from the diamine compound constituting the polymer (P).

[0108] [Structural units derived from tetracarboxylic acid derivatives] The structural units (hereinafter also referred to as "structural units (TA)") derived from tetracarboxylic acid derivatives that the polymer (P) possesses are not particularly limited, as long as they are compounds that can be condensed with diamine compounds to obtain a polymer. Examples of monomers that give structural units (TA) include aliphatic tetracarboxylic dianhydrides, aromatic tetracarboxylic dianhydrides, and their derivatives. Examples of aliphatic tetracarboxylic dianhydrides include linear tetracarboxylic dianhydrides and alicyclic tetracarboxylic dianhydrides.

[0109] Specific examples of these include, as chain-like tetracarboxylic dianhydrides, 1,2,3,4-butanetetracarboxylic dianhydride, ethylenediaminetetraacetic acid dianhydride, etc.; as alicyclic tetracarboxylic dianhydrides, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 5-(2,5-dioxotetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuran-3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho Examples of dianhydrides include to[1,2-c]furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, cyclopentanetetracarboxylic acid dianhydride, cyclohexanetetracarboxylic acid dianhydride, etc., and 3,5,6-tricarboxy-2-carboxymethylnorbornane-2:3,5:6-dianhydride; and as aromatic tetracarboxylic acid dianhydrides, examples include pyromellitic acid dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic acid anhydride, ethylene glycol bisanhydrotrimate, 4,4'-carbonyl diphthalic acid anhydride, and 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, etc.

[0110] The tetracarboxylic acid derivative that provides the structural unit (TA) preferably contains an aliphatic tetracarboxylic dianhydride or its derivative, and more preferably contains an alicyclic tetracarboxylic dianhydride or its derivative, in that it can improve the coatability and printability (especially inkjet coatability) of the resulting liquid crystal alignment agent and produce a liquid crystal alignment film that exhibits good liquid crystal alignment. In the polymer (P), the proportion of structural units derived from the alicyclic tetracarboxylic dianhydride or its derivative is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 50 mol% or more, relative to the total structural units derived from the tetracarboxylic acid derivative constituting the polymer (P).

[0111] [Synthesis of compounds] The methods for producing diamine compounds (DA-1), (DA-2), (DB-1), and (DB-2) are not particularly limited and can be produced by appropriately combining standard organic chemistry methods. One example is to first synthesize a dinitro intermediate having a nitro group instead of a primary amino group in the target diamine compound, and then aminate the nitro group of the obtained dinitro intermediate using a suitable reducing system.

[0112] The method for synthesizing the dinitro intermediate can be appropriately selected depending on the molecular structure of the target diamine compound. For example, the compound represented by the above formula (a1-1) is A 1 A secondary amine compound having a corresponding structure, and "Y 1 -R 1 -Ar 1 -(NO2)2" represents a dinitro compound (Y 1 A method of reacting an amino group with a functional group that can react with it (e.g., halogen atom, carboxyl group, halocarbonyl group, etc.); A 1 A secondary amine compound having a corresponding structure, and "Y 1 -R 1 -Y 2 Compounds having a substructure represented by " (Y 2 After reacting with a protected carboxyl group, the intermediate obtained by the reaction is mixed with Ar 1 A method of reacting a dinitro compound having a corresponding structure and a primary amino group with A 1 -R 1 A hydroxy compound having a corresponding structure and Ar 1 It can be synthesized by reacting a dinitro compound having the corresponding structure and halogen atom with [the compound name], etc. However, the method of synthesizing the diamine compound is not limited to the above.

[0113] [Synthesis of polymers (P)] The polymer (P) can be obtained by a method that includes a step of polymerizing monomers containing a tetracarboxylic acid derivative and a diamine compound.

[0114] • Polyamic acid When the polymer (P) is a polyamic acid, the polyamic acid (hereinafter also referred to as "polyamic acid (P)") can be obtained by reacting a tetracarboxylic dianhydride with a diamine compound, along with a molecular weight modifier as needed.

[0115] In the synthesis reaction of polyamic acid (P), the ratio of tetracarboxylic dianhydride to diamine compound used is preferably such that the acid anhydride groups of the tetracarboxylic dianhydride are 0.2 to 2 equivalents per 1 equivalent of amino groups of the diamine compound. Examples of molecular weight modifiers include acid monoanhydrides such as maleic anhydride, phthalic anhydride, and itaconic anhydride; monoamine compounds such as aniline, cyclohexylamine, and n-butylamine; and monoisocyanate compounds such as phenyl isocyanate and naphthyl isocyanate. The ratio of molecular weight modifier used is preferably 20 parts by mass or less per 100 parts by mass of the total amount of tetracarboxylic dianhydride and diamine compound used.

[0116] In the synthesis reaction of polyamic acid (P), the reaction temperature is preferably -20°C to 150°C, and the reaction time is preferably 0.1 to 24 hours. Examples of organic solvents used in the reaction include aprotic polar solvents, phenolic solvents, alcoholic solvents, ketone solvents, esteric solvents, etheric solvents, halogenated hydrocarbons, and hydrocarbons. Of these, it is preferable to use one or more selected from the group consisting of N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide, m-cresol, xylenol, and halogenated phenol as the reaction solvent, or to use a mixture of one or more of these and other organic solvents (e.g., butyl cellosolve, diethylene glycol diethyl ether, etc.). The amount of organic solvent used is preferably such that the total amount of tetracarboxylic dianhydride and diamine compound is 0.1 to 50% by mass of the total amount of the reaction solution.

[0117] When a polymer solution is obtained by dissolving polyamic acid (P) through the above polymerization, this polymer solution may be used directly for the preparation of the liquid crystal alignment agent, or the polyamic acid (P) contained in the polymer solution may be isolated before being used for the preparation of the liquid crystal alignment agent.

[0118] • Polyamic acid esters When the polymer (P) is a polyamic acid ester, the polyamic acid ester can be obtained, for example, by [I] reacting polyamic acid (P) with an esterifying agent, [II] reacting a tetracarboxylic acid diester with a diamine compound, or [III] reacting a tetracarboxylic acid dihalide with a diamine compound. The polyamic acid ester may have only an amic acid ester structure, or it may be a partially esterified product in which both an amic acid structure and an amic acid ester structure coexist. The reaction solution obtained by dissolving the polyamic acid ester may be used as is for the preparation of the liquid crystal alignment agent. Alternatively, the polyamic acid ester contained in the reaction solution may be isolated, and the isolated polyamic acid ester may be used for the preparation of the liquid crystal alignment agent.

[0119] Polyimide When the polymer (P) is a polyimide, the polyimide (hereinafter also referred to as "polyimide (P)") can be obtained, for example, by dehydrating and cyclizing a polyamic acid (P) to imidize it. Polyimide (P) may be a fully imidized product in which all of the amic acid structure present in its precursor, polyamic acid (P), has been dehydrated and cyclized, or it may be a partially imidized product in which only a part of the amic acid structure has been dehydrated and cyclized, resulting in the coexistence of amic acid structures and imide ring structures. The imidization rate of polyimide (P) is preferably 20 to 99%, and more preferably 30 to 90%. The imidization rate is expressed as a percentage of the ratio of the number of imide ring structures to the total number of amic acid structures and imide ring structures in the polyimide. Here, part of the imide ring may be an isoimide ring.

[0120] The dehydration ring closure of the polyamic acid (P) is preferably carried out by dissolving the polyamic acid (P) in an organic solvent, adding a dehydrating agent and a dehydration ring closure catalyst to this solution, and heating as necessary. In this method, as the dehydrating agent, for example, acid anhydrides such as acetic anhydride, propionic anhydride, trifluoroacetic anhydride, etc. can be used. The usage amount of the dehydrating agent is preferably 0.01 to 20 moles per 1 mole of the amic acid structure of the polyamic acid (P). As the dehydration ring closure catalyst, for example, tertiary amines such as pyridine, collidine, lutidine, triethylamine, etc. can be used. The usage amount of the dehydration ring closure catalyst is preferably 0.01 to 10 moles per 1 mole of the dehydrating agent used.

[0121] Examples of the organic solvent used in the dehydration ring closure reaction include the organic solvents exemplified as those used in the synthesis of the polyamic acid (P). The reaction temperature of the dehydration ring closure reaction is preferably 0 to 180°C. The reaction time is preferably 1.0 to 120 hours. The reaction solution containing the polyimide (P) may be directly used for the preparation of the liquid crystal aligning agent. Also, the polyimide (P) may be isolated from the reaction solution and the isolated polyimide (P) may be used for the preparation of the liquid crystal aligning agent. The polyimide (P) can also be obtained by the dehydration ring closure of the polyamic acid ester.

[0122] The solution viscosity of the polymer (P) preferably has a solution viscosity of 10 to 800 mPa·s when it is a solution with a concentration of 10% by mass, and more preferably has a solution viscosity of 15 to 500 mPa·s. The solution viscosity (mPa·s) is the value measured at 25°C using an E-type rotational viscometer for a polymer solution with a concentration of 10% by mass prepared using a good solvent of the polymer (P) (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0123] The weight-average molecular weight (Mw) of the polymer (P), measured by gel permeation chromatography (GPC) in terms of polystyrene, is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the number-average molecular weight (Mn) measured by GPC in terms of polystyrene, is preferably 7 or less, and more preferably 5 or less.

[0124] The content of polymer (P) in the liquid crystal alignment agent is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more, based on the total amount of solids contained in the liquid crystal alignment agent (i.e., the total mass of components other than the solvent in the liquid crystal alignment agent).

[0125] <Other ingredients> The first liquid crystal alignment agent may contain, in addition to the polymer (P), components other than the polymer (P) (hereinafter also referred to as "other components") as needed.

[0126] • Polymer (Q) The first liquid crystal alignment agent may further contain a polymer (Q) that does not have either substructure (A) or substructure (B). The main skeleton of polymer (Q) is not particularly limited. Examples of polymer (Q) include polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, polyester, polyenamine, polyurea, polyamide, polyamideimide, polybenzoxazole precursor, polybenzoxazole, cellulose derivative, polyacetal, and addition polymers (e.g., (meth)acrylic polymers, styrene polymers, maleimide polymers, styrene-maleimide copolymers). Of these, polymer (Q) is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, and addition polymers.

[0127] When polymer (Q) is included in the first liquid crystal alignment agent, the content of polymer (Q) is preferably 1 part by mass or more, and more preferably 2 parts by mass or more, based on 100 parts by mass of the total amount of polymer (P) and polymer (Q) contained in the first liquid crystal alignment agent. Furthermore, the content of polymer (Q) is preferably 95 parts by mass or less, and more preferably 90 parts by mass or less, based on 100 parts by mass of the total amount of polymer (P) and polymer (Q) contained in the first liquid crystal alignment agent.

[0128] ·solvent The first liquid crystal alignment agent is prepared as a liquid composition in which a polymer (P) and other components used as needed are dispersed or dissolved in a suitable solvent, preferably.

[0129] Organic solvents are preferred as solvents. Specific examples include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,2-dimethyl-2-imidazolidinone, 1,3-dimethyl-2-imidazolidinone, phenol, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, diacetone alcohol, 1-hexanol, 2-hexanol, propane-1,2-diol, 3-methoxy-1-butanol, ethylene glycol monomethyl ether, methyl lactate, ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl acetoacetate, ethyl acetoethyl acetate, ethyl propionate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, and ethylene glycol-i-propyl ether. Examples of solvents include ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisopentyl ether, ethylene carbonate, propylene carbonate, propylene glycol monomethyl ether (PGME), diethylene glycol diethyl ether acetate, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol diacetate, cyclopentanone, and cyclohexanone. As solvents, one type can be used alone or two or more types can be used in combination.

[0130] Other components to be incorporated into the first liquid crystal alignment agent include, in addition to those mentioned above, crosslinking agents, antioxidants, metal chelating compounds, curing accelerators, surfactants, fillers, dispersants, photosensitizers, and the like. The proportion of these other components can be appropriately selected for each compound, as long as it does not impair the effects of the present disclosure.

[0131] The solid content concentration in the first liquid crystal alignment agent (the ratio of the total mass of components other than the solvent in the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent) is appropriately selected considering viscosity, volatility, etc. The solid content concentration of the liquid crystal alignment agent is preferably in the range of 1 to 10% by mass. A solid content concentration of 1% by mass or more is preferable because it allows for sufficient film thickness of the coating and enables the production of a liquid crystal alignment film exhibiting better liquid crystal alignment properties. On the other hand, a solid content concentration of 10% by mass or less allows for a coating film of appropriate thickness, making it easier to obtain a liquid crystal alignment film exhibiting good liquid crystal alignment properties, and the viscosity of the liquid crystal alignment agent tends to be appropriate, resulting in good coatability.

[0132] <Second liquid crystal alignment agent> The second liquid crystal alignment agent contains a polymer (P), which is a polymer containing structural units derived from a diamine compound having substructure (B), and a compound having substructure (A) (excluding the polymer; hereinafter also referred to as "compound (MA)"). In the following explanation, the explanation of parts that overlap with the first liquid crystal alignment agent will be omitted, and the explanation of the first liquid crystal alignment agent will be used as a reference.

[0133] <Polymer (P)> The polymer (P) contained in the second liquid crystal alignment agent is a polymer having structural units derived from a tetracarboxylic acid derivative and structural units derived from a diamine compound within a single molecule, and includes the structural unit (UB) described above as the structural unit derived from the diamine compound. Specific examples and preferred examples of structural unit (UB), as well as the proportion of structural unit (UB) in polymer (P), are described in the description for the first liquid crystal alignment agent.

[0134] The polymer (P) may further contain structural units different from structural unit (UB) as structural units derived from the diamine compound. Examples of such structural units are the same as those described as other structural units in the description of the first liquid crystal alignment agent. The polymer (P) contained in the second liquid crystal alignment agent may contain structural unit (UA) together with structural unit (UB). It is preferable that the polymer (P) contained in the second liquid crystal alignment agent does not contain structural unit (UA) because it is easier to adjust the content of structural unit (UA) in the liquid crystal alignment agent.

[0135] In the second liquid crystal alignment agent, the content of polymer (P) is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more, based on the total amount of solids contained in the liquid crystal alignment agent. Furthermore, the content of polymer (P) is preferably 99% by mass or less, and more preferably 98% by mass or less, based on the total amount of solids contained in the liquid crystal alignment agent.

[0136] <Compound (MA)> Compound (MA) has at least one substructure (A) selected from the group consisting of a substituted heterocyclic structure substituted with an electron-withdrawing group F1, a quinone structure, and a tetracyanoquinodimethane structure. Specific and preferred examples of the substituted heterocyclic structure of compound (MA) are similar to those described as specific and preferred examples of the substituted heterocyclic structure of the diamine compound (DA-1) above.

[0137] Specific and preferred examples of the quinone structure of compound (MA) are similar to those described as specific and preferred examples of the quinone structure of the diamine compound (DA-2) above. From the viewpoint of enhancing interaction with substructure (B), it is preferable that the quinone structure of compound (MA) has a secondary amino group (-NH-) or a tertiary amino group bonded to the ring. The number of secondary and tertiary amino groups bonded to the ring of the quinone structure (the total amount if there are two or more types) is preferably one or two. The tetracyanoquinodimethane structure of compound (MA) may have substituents in the ring portion. Examples of such substituents include C1-C3 alkyl groups, C1-C3 alkoxy groups, halogen atoms, and the like.

[0138] Specific examples of compounds (MA) include compounds having a substituted heterocyclic structure substituted with an electron-withdrawing group F1, such as those represented by formulas (d-6-1) to (d-6-3) below; compounds having a quinone structure, such as those represented by formulas (d-6-4) to (d-6-7) below; and compounds having a tetracyanoquinodimethane structure, such as those represented by formulas (d-6-8) to (d-6-14) below. [ka]

[0139] In the second liquid crystal alignment agent, the content of compound (MA) is preferably 1 part by mass or more, more preferably 2 parts by mass or more, and even more preferably 5 parts by mass or more, based on 100 parts by mass of the total amount of polymer components contained in the liquid crystal alignment agent. Furthermore, the content of compound (MA) is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, and even more preferably 20 parts by mass or less, based on 100 parts by mass of the total amount of polymer components contained in the liquid crystal alignment agent.

[0140] The second liquid crystal alignment agent may, if necessary, further contain components other than the polymer (P) and compound (MA). Specific examples, preferred examples, and content ratios of such components are described in the description of other components in the first liquid crystal alignment agent.

[0141] <Liquid crystal alignment films and liquid crystal elements> The liquid crystal alignment film of this disclosure is manufactured using a liquid crystal alignment agent prepared as described above. The liquid crystal element of this disclosure comprises a liquid crystal alignment film formed using the liquid crystal alignment agent described above. The liquid crystal driving method in the liquid crystal element is not particularly limited and can be applied to various modes such as TN type, STN type, VA type (including VA-MVA type, VA-PVA type, etc.), IPS type, FFS type, OCB (Optically Compensated Bend) type, and PSA (Polymer Sustained Alignment) type. The liquid crystal element can be manufactured by a method including, for example, the following steps 1 to 3. In step 1, the substrate used differs depending on the desired operating mode. Steps 2 and 3 are common to each operating mode.

[0142] <Step 1: Formation of the coating> First, a liquid crystal alignment agent is applied to the substrate, and preferably the applied surface is heated to form a coating on the substrate. As the substrate, for example, glass such as float glass or soda glass; or transparent substrates made of plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, or poly(alicyclic olefin) can be used. As the transparent conductive film provided on one side of the substrate, a NESA film (registered trademark of PPG, Inc., USA) made of tin oxide (SnO2), or an ITO film made of indium oxide-tin oxide (In2O3-SnO2) can be used. When manufacturing TN, STN, or VA type liquid crystal elements, two substrates with patterned transparent conductive films are used. On the other hand, when manufacturing IPS or FFS type liquid crystal elements, a substrate with comb-shaped patterned electrodes and a counter substrate without electrodes are used.

[0143] The method for applying the liquid crystal alignment agent to the substrate is not particularly limited. The liquid crystal alignment agent can be applied to the substrate by, for example, a spin coating method, a printing method (e.g., offset printing method, flexographic printing method, etc.), an inkjet method, a slit coating method, a bar coater method, an extrusion die method, a direct gravure coater method, a chamber doctor coater method, an offset gravure coater method, an impregnation coater method, an MB coater method, etc.

[0144] After applying the liquid crystal alignment agent, preheating (pre-bake) is preferably performed to prevent dripping of the applied liquid crystal alignment agent. The pre-bake temperature is preferably 30 to 200°C, and the pre-bake time is preferably 0.25 to 10 minutes. After that, a firing (post-bake) step is performed to completely remove the solvent and, if necessary, to thermally imide the amic acid structure present in the polymer. The firing temperature (post-bake temperature) at this time is preferably 80 to 280°C, more preferably 80 to 250°C. The post-bake time is preferably 5 to 200 minutes. The film thickness of the formed film is preferably 0.001 to 1 μm.

[0145] <Step 2: Orientation Treatment> When manufacturing TN, STN, IPS, or FFS type liquid crystal elements, the coating film formed in step 1 is subjected to a process (alignment treatment) to impart liquid crystal alignment ability. This imparts the liquid crystal molecule alignment ability to the coating film, making it a liquid crystal alignment film. As the alignment treatment, it is preferable to use a rubbing treatment in which the surface of the coating film formed on the substrate is rubbed with cotton or nylon, or a photo-alignment treatment in which the coating film is irradiated with light to impart liquid crystal alignment ability. When manufacturing vertically aligned liquid crystal elements, the coating film formed in step 1 may be used as is as a liquid crystal alignment film, or an alignment treatment may be applied to the coating film to further enhance its liquid crystal alignment ability. A liquid crystal alignment film suitable for vertically aligned liquid crystal elements can also be preferably used for PSA type liquid crystal elements.

[0146] Light irradiation for photo-alignment can be carried out by methods such as irradiating the coating film after the post-bake process, irradiating the coating film after the pre-bake process but before the post-bake process, or irradiating the coating film while it is being heated in at least one of the pre-bake or post-bake processes. As radiation to irradiate the coating film, for example, ultraviolet light and visible light including light with wavelengths of 150 to 800 nm can be used. Preferably, ultraviolet light including light with wavelengths of 200 to 400 nm is used. If the radiation is polarized, it may be linearly polarized or partially polarized. If the radiation used is linearly polarized or partially polarized, irradiation may be carried out from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these. In the case of unpolarized radiation, the irradiation direction should be oblique.

[0147] Examples of light sources that can be used include low-pressure mercury lamps, high-pressure mercury lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, and excimer lasers. The radiation dose is preferably 200 to 30,000 J / m². 2 And more preferably, 500~10,000 J / m 2 In addition, after light irradiation to impart orientation ability, the substrate surface may be washed with, for example, water, an organic solvent (e.g., methanol, isopropyl alcohol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, etc.), or a mixture thereof, or the substrate may be heated.

[0148] <Step 3: Liquid Crystal Cell Construction> A liquid crystal cell is manufactured by preparing two substrates on which a liquid crystal alignment film is formed as described above, and placing liquid crystal between the two substrates which are placed opposite each other. Methods for manufacturing a liquid crystal cell include, for example, placing two substrates opposite each other with a gap in between so that the liquid crystal alignment films face each other, bonding the periphery of the two substrates with a sealant, injecting and filling the cell gap surrounded by the substrate surface and the sealant, and sealing the injection hole, or the ODF method. As the sealant, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as spacers can be used. Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals, with nematic liquid crystals being preferred.

[0149] In PSA mode, a polymerizable compound (e.g., a polyfunctional (meth)acrylate compound) is packed into the cell gap along with the liquid crystal, and after the liquid crystal cell is constructed, a voltage is applied between the conductive films of a pair of substrates, and the liquid crystal cell is irradiated with light. When manufacturing a PSA type liquid crystal element, the proportion of polymerizable compound used is, for example, 0.01 to 3 parts by mass, preferably 0.05 to 1 part by mass, per 100 parts by mass of the total liquid crystal.

[0150] When manufacturing liquid crystal display devices, a polarizing plate is then bonded to the outer surface of the liquid crystal cell. Examples of polarizing plates include a polarizing film called an "H film," which is made by stretching and oriented polyvinyl alcohol while absorbing iodine, sandwiched between cellulose acetate protective films, or a polarizing plate made of the H film itself.

[0151] The liquid crystal elements of this disclosure can be effectively applied to a variety of uses. Specifically, they can be used, for example, in various display devices such as watches, portable game consoles, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, various monitors, liquid crystal televisions, information displays, as well as in dimming devices, phase difference films, and the like. [Examples]

[0152] The embodiments will be described in more detail below based on the examples, but the present invention is not to be interpreted as being limited by the following embodiments.

[0153] In the following examples, the imidization rate of polyimide in the polymer solution, as well as the weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polymer, were measured by the following methods. The required amounts of the raw material compounds and polymers used in the following examples were obtained by repeating the synthesis on the synthesis scale shown in the synthesis examples below as needed.

[0154] [Imidification rate of polyimides] A polyimide solution was added to pure water, and the resulting precipitate was thoroughly dried under reduced pressure at room temperature. Then it was dissolved in deuterated dimethyl sulfoxide, with tetramethylsilane as the reference material, at room temperature. 1 1H-NMR measurements were performed. 1 The imidization rate [%] was determined from the 1H-NMR spectrum using the following formula (I). Imidization rate [%] = (1 - (A 1 / ( A 2 ×α)))×100 …(I) (In formula (I), A 1 This represents the peak area originating from the proton of the NH group, appearing around a chemical shift of 10 ppm. 2 α represents the peak area derived from other protons, and α is the ratio of other protons to one proton of the NH group in the polymer precursor (polyamic acid).

[0155] [Weight-average molecular weight (Mw) and number-average molecular weight (Mn)] Mw and Mn are polystyrene equivalent values ​​measured by GPC under the following conditions. Column: TSKgelGRCXLII, manufactured by Tosoh Corporation. Solvent: Tetrahydrofuran Temperature: 40℃ Pressure: 68 kgf / cm² 2

[0156] The abbreviations for the compounds are as follows. In the following, the compound represented by formula (X) may simply be referred to as "compound (X)".

[0157] (Tetracarboxylic acid dianhydride) [ka]

[0158] (Diamine compounds) [ka] [ka]

[0159] [ka] [ka] [ka] [ka]

[0160] [ka] [ka]

[0161] (Monomers containing carbon-carbon unsaturated bonds) [ka] [ka]

[0162] (Additives) [ka] [ka]

[0163] (solvent) NMP:N-methyl-2-pyrrolidone NEP:N-ethyl-2-pyrrolidone GBL: γ-Butyrolactone BC: Butyl cellosolve DEDG: Diethylene glycol diethyl ether DIBK: Diisobutylketone

[0164] (Synthetic solvent) DMF: N,N-dimethylformamide THF: Tetrahydrofuran DMAc: Dimethylacetamide

[0165] <Synthesis of Compounds> [Synthesis Example 1-1] Synthesis of Compound (DA-1) 4,5-Dicyanoimidazole (12.7 mmol) and potassium carbonate (15.3 mmol) were added to DMF (15 mL) and stirred at room temperature under nitrogen for 30 minutes. Then, 3,5-Dinitrobenzyl chloride (15.2 mmol) was added to the stirring reaction mixture and stirred at room temperature under nitrogen for 6 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DA-1-1) in 95% yield. Next, the intermediate (DA-1-1) (15.2 mmol), zinc powder (303 mmol), and ammonium chloride (152 mmol) were added to a mixed solvent of THF (30 mL) and ethanol (6 mL), and the mixture was stirred under nitrogen at 0°C. Then, pure water (432 mmol) was added dropwise, and stirring was continued at 0°C for 1 hour. After that, the mixture was stirred under nitrogen at room temperature for 5 hours. After the reaction was complete, the reaction solution was filtered through Celite, ethyl acetate was added, and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure to obtain the yellow solid compound (DA-1) in 70% yield. Figure 1 shows the compound (DA-1). 1 The measurement results of the H-NMR spectrum (DMSO-d6, 400MHz) are shown. API-ES m / z:239.1(calc. for [M+H] + :239.10) [ka]

[0166] [Synthesis Example 1-2] Synthesis of Compound (DA-2) 4,5-dicyanoimidazole (12.7 mmol) and triethylamine (15.3 mmol) were added to THF (15 mL) and stirred under nitrogen at 0°C for 10 minutes. Next, 3,5-dinitrobenzoyl chloride (12.7 mmol) dissolved in 10 mL of THF was added dropwise to the stirring reaction mixture, and stirring was continued at 0°C for 1 hour. Subsequently, the mixture was stirred under nitrogen at room temperature for 5 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DA-2-1) in 90% yield. Next, the intermediate (DA-2-1) (11.4 mmol) and 5% Pd / C (0.73 g) were added to a mixed solvent of THF (12 mL) and ethanol (12 mL), and the mixture was stirred under nitrogen at 0°C for 10 minutes. Then, hydrazine monohydrate (68.6 mmol) was added dropwise to the stirring reaction mixture, and stirring was continued at 0°C for 30 minutes. After that, the mixture was stirred under nitrogen at 66°C for 6 hours. After the reaction was complete, the reaction solution was filtered through Celite, ethyl acetate was added, and the mixture was separated and washed with water. Compound (DA-2) was obtained in 85% yield by concentrating the organic phase under reduced pressure. [ka]

[0167] [Synthesis Example 1-3] Synthesis of Compound (DA-3) 4,5-Dicyanoimidazole (12.7 mmol) and potassium carbonate (25.4 mmol) were added to DMF (25 mL) and stirred at room temperature under nitrogen for 30 minutes. Then, ethyl 3-bromopropionate (15.2 mmol) was added to the stirring reaction mixture and stirred at 100°C under nitrogen for 6 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DA-3-1) in 80% yield. The intermediate (DA-3-1) (10.2 mmol) was added to a 1 mol / L aqueous hydrochloric acid solution (20 mL) and stirred under reflux for 8 hours. The solution was then concentrated, washed with ethanol, and dried to obtain the compound represented by the following formula (DA-3-2) in 80% yield. Intermediate (DA-3-2) (8.1 mmol) was added to thionyl chloride (81.3 mmol). DMF (0.08 mmol) was added while stirring under nitrogen at room temperature. The mixture was then stirred under reflux for 1.5 hours. After the reaction was complete, the reaction mixture was concentrated and the residue was dissolved in THF (10 mL). This solution is designated as Solution A. Separately, 3,5-dinitroaniline (8.1 mmol) and triethylamine (16.3 mmol) were dissolved in THF (10 mL) and stirred under nitrogen at 0°C for 10 minutes. Solution A was added dropwise to this solution and stirring was continued at 0°C for 1 hour. The mixture was then stirred under nitrogen at room temperature for 3 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DA-3-3) in 85% yield. The intermediate (DA-3-3) (6.9 mmol) and 5% Pd / C (0.44 g) were added to a mixed solvent of THF (8 mL) and ethanol (8 mL), and the mixture was stirred under nitrogen at 0°C for 10 minutes. Next, hydrazine monohydrate (41.5 mmol) was added dropwise to the stirring reaction mixture, and stirring was continued at 0°C for 30 minutes. After that, the mixture was stirred under nitrogen at room temperature for 6 hours. After the reaction was complete, the reaction solution was filtered through Celite, ethyl acetate was added, and the mixture was separated and washed with water. Compound (DA-3) was obtained in 80% yield by concentrating the organic phase under reduced pressure. [ka]

[0168] [Synthesis Example 1-4] Synthesis of Compound (DA-4) Compound (DA-4) was obtained by the same method as in Synthesis Example 1-1, except that 4,5-dicyanoimidazole was replaced with 2,4,5-tribromoimidazole in the first step of the synthesis scheme of Synthesis Example 1-1.

[0169] [Synthesis Example 1-5] Synthesis of Compound (DA-5) Compound (DA-5) was obtained by the same method as in Synthesis Example 1-1, except that 3,5-dinitrobenzyl chloride was replaced with 2,4-dinitrobenzyl chloride in the first step of the synthesis scheme of Synthesis Example 1-1.

[0170] [Synthesis Example 1-6] Synthesis of Compound (DA-6) Compound (DA-6-1) (12.3 mmol) was added to DMAc (20 mL) and stirred under nitrogen at 0°C for 10 minutes. Then, sodium tert-butoxide (18.5 mmol) was added to the stirring reaction mixture in several portions, and stirring continued at 0°C for 30 minutes. Subsequently, 2,4-dinitrofluorobenzene (13.5 mmol) dissolved in DMAc (5 mL) was added to the stirring reaction mixture, and the mixture was stirred under nitrogen at 0°C for 6 hours. After the reaction was complete, water was added, followed by ethyl acetate and liquid-liquid washing. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DA-6-2) in 90% yield. The intermediate (DA-6-2) (11.1 mmol) and 5% Pd / C (0.71 g) were added to a mixed solvent of THF (12 mL) and ethanol (12 mL), and the mixture was stirred under nitrogen at 0°C for 10 minutes. Next, hydrazine monohydrate (66.4 mmol) was added dropwise to the stirring reaction mixture, and stirring was continued at 0°C for 30 minutes. Subsequently, the mixture was stirred under nitrogen at 66°C for 6 hours. After the reaction was complete, the reaction solution was filtered through Celite, ethyl acetate was added, and the mixture was separated and washed with water. Compound (DA-6) was obtained in 90% yield by concentrating the organic phase under reduced pressure. Compound (DA-6-1) was synthesized according to a known document (Bioorganic & Medicinal Chemistry Letters (2019), 29(9), 1138-1142). [ka]

[0171] [Synthesis Example 1-7] Synthesis of Compound (DA-7) Compound (DA-7) was obtained by the same method as in Synthesis Example 1-1, except that 4,5-dicyanoimidazole was replaced with 4-acetylimidazole in the first step of the synthesis scheme of Synthesis Example 1-1.

[0172] [Synthesis Example 1-8] Synthesis of Compound (DA-8) Compound (DA-8) was synthesized in the same manner as in Synthesis Example 1-1, except that in the first step of the synthesis scheme of Synthesis Example 1-1, 4,5-dicyanoimidazole was replaced with 4,5-bis(trifluoromethyl)imidazole and 3,5-dinitrobenzyl chloride was replaced with 2,4-dinitrobenzyl chloride.

[0173] [Synthesis Examples 1-9] Synthesis of Compound (DA-9) 2,5-Dimethoxy-1,4-benzoquinone (17.8 mmol) was added to ethanol (25 mL) and stirred at room temperature under nitrogen. 2-(4-aminophenyl)ethylamine (36.0 mmol) dissolved in ethanol (15 mL) was added dropwise to the reaction mixture and stirred at room temperature under nitrogen for 5 hours. After the reaction was complete, the precipitated solid was filtered off, washed with ethanol, and dried to obtain the maroon solid compound (DA-9) in 95% yield. Figure 2 shows the compound (DA-9). 1 The measurement results of the H-NMR spectrum (DMSO-d6, 400MHz) are shown. API-ES m / z:377.2(calc. for [M+H] + :377.20) [ka]

[0174] [Synthesis Example 1-10] Synthesis of compound (DA-10) Compound (DA-10) was obtained by the same method as in Synthesis Example 1-9, except that 2-(4-aminophenyl)ethylamine was replaced with 4-aminobenzylamine.

[0175] [Synthesis Example 1-11] Synthesis of compound (DA-11) 3-(4-nitrophenyl)propionic acid (15.0 mmol) was added to thionyl chloride (150.0 mmol). Under nitrogen at room temperature, DMF (0.15 mmol) was added while stirring. Then, the mixture was stirred under reflux for 1.5 hours. After the reaction was complete, the reaction mixture was concentrated and the residue was dissolved in THF (20 mL). This solution is designated as solution B. Separately, ethylenediamine (30.0 mmol) and triethylamine (60.0 mmol) were dissolved in THF (30 mL) and stirred under nitrogen at 0°C for 10 minutes. Solution B was added dropwise to this solution and stirring was continued at 0°C for 1 hour. Then, the mixture was stirred under nitrogen at room temperature for 3 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DA-11-1) in 70% yield. The intermediate (DA-11-1) (10.5 mmol) and 5% Pd / C (0.67 g) were added to ethanol (25 mL), and the reaction vessel was purged with nitrogen. Then, the reaction vessel was purged with hydrogen, and the mixture was stirred at room temperature for 12 hours. After the reaction was complete, THF was added to the reaction solution, and the mixture was filtered by Celite. The filtrate was concentrated under reduced pressure to obtain the compound represented by the following formula (DA-11-2) in 90% yield. For the third step of the synthesis scheme below, compound (DA-11) was obtained by the same method as in Synthesis Example 1-9, except that 2-(4-aminophenyl)ethylamine was changed to the intermediate (DA-11-2) and the solvent was changed from ethanol to THF. [ka]

[0176] [Synthesis Example 1-12] Synthesis of compound (DA-12) 2-amino-5-nitrobenzylamine (10.0 mmol) and 5% Pt / C (1.56 g) were added to ethanol (40 mL), and the reaction vessel was purged with nitrogen. Then, the reaction vessel was purged with hydrogen, and the mixture was stirred at room temperature for 12 hours. After the reaction was complete, THF was added to the reaction solution, and the mixture was filtered by Celite. The filtrate was concentrated under reduced pressure to obtain the compound represented by the following formula (DA-12-1) in 90% yield. 2,5-Dimethoxy-1,4-benzoquinone (18.0 mmol) was added to ethanol (35 mL) and stirred at room temperature under nitrogen. Intermediate (DA-12-1) (9.0 mmol), dissolved in ethanol (15 mL), was added dropwise to the reaction mixture and stirred at room temperature under nitrogen for 3 hours. After the reaction was complete, the solvent was removed and the residue was purified by silica gel column chromatography (eluted with a mixed solvent of ethyl acetate and hexane) to obtain compound (DA-12). [ka]

[0177] [Synthesis Example 1-13] Synthesis of compound (DA-13) Compound (DA-13) was obtained by the same method as in Synthesis Example 1-12, except that 2,5-dimethoxy-1,4-benzoquinone was replaced with 2,3-dimethylbenzoquinone in the second step of the synthesis scheme in Synthesis Example 1-12.

[0178] [Synthesis Example 1-14] Synthesis of compound (DA-14) The following formula (DA-14-1) (21.0 mmol) and 5% Pd / C (1.34 g) were added to ethanol (50 mL), and the reaction vessel was purged with nitrogen. Then, the reaction vessel was purged with hydrogen, and the mixture was stirred at room temperature for 12 hours. After the reaction was complete, THF was added to the reaction solution, and the mixture was filtered by Celite. The filtrate was concentrated under reduced pressure to obtain the compound represented by the following formula (DA-14-2) in 90% yield. Regarding the second step of the synthesis scheme below, the compound (DA-14) was synthesized in the same manner as in Synthesis Example 1-12, except that intermediate (DA-12-1) was changed to intermediate (DA-14-2) in the second step of the synthesis scheme of Synthesis Example 1-12, and compound (DA-14) was obtained. The compound represented by the following formula (DA-14-1) was synthesized according to known literature (Oriental Journal of Chemistry (2013), 29(1), 17-22). [ka]

[0179] [Synthesis Example 1-15] Synthesis of compound (DB-23) Phenothiazine (10.0 mmol) and 3,5-dinitrobenzyl chloride (10.0 mmol) were added to THF (30 mL) and stirred at room temperature under nitrogen for 10 minutes. Then, sodium hydroxide (13.0 mmol) dissolved in pure water (15 mL) was added to the stirring reaction mixture and stirred at room temperature under nitrogen for 6 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (eluted with a mixed solvent of ethyl acetate and hexane) to obtain the following formula (DB-23-1) in 70% yield. Next, intermediate (DB-23-1) (7.0 mmol), zinc powder (140 mmol), and ammonium chloride (70.0 mmol) were added to a mixed solvent of THF (30 mL) and ethanol (5 mL), and stirred under nitrogen at 0°C. Then, pure water (200 mmol) was added dropwise, and stirring continued at 0°C for 1 hour. After that, stirring was carried out under nitrogen at room temperature for 5 hours. After the reaction was complete, the reaction solution was filtered through Celite, ethyl acetate was added, and the mixture was separated and washed with water. Compound (DB-23) was obtained in 90% yield by concentrating the organic phase under reduced pressure. 1 The measurement results for the H-NMR spectrum (DMSO-d6, 400MHz, ppm) are as follows. δ= 7.05(m,4H),6.87(t,J=7.6 Hz, 2H), 6.74 (d, J=8.8 Hz, 2H), 5.72 (s, 2H), 5.68 (s, 1H), 4.77 (s, 2H), 4.72(s, 4H).API-ES m / z:320.1(calc. for [M+H] + :320.12) [ka]

[0180] [Synthesis Example 1-16] Synthesis of Compound (DB-24) 3,5-Dinitroaniline (15.0 mmol) and triethylamine (18.0 mmol) were added to THF (20 mL) and stirred under nitrogen at 0°C for 10 minutes. Then, 3-bromopropionyl chloride (15.0 mmol) dissolved in THF (10 mL) was added dropwise, and stirring continued at 0°C for 1 hour. After that, stirring was carried out under nitrogen at room temperature for 3 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DB-24-1) in 90% yield. The second and third reactions in the following synthesis scheme were synthesized in the same manner as in Synthesis Example 1-15, except that 3,5-dinitrobenzyl chloride was replaced with intermediate (DB-24-1), to obtain compound (DB-24). [ka]

[0181] [Synthesis Example 1-17] Synthesis of compound (DB-25) 2,4-Dinitrophenol (10.0 mmol) and potassium carbonate (20.0 mmol) were added to DMF (20 mL) and stirred at room temperature under nitrogen for 10 minutes. Then, 1,2-Dibromoethane (20.0 mmol) dissolved in DMF (5 mL) was added to the stirring reaction mixture. The mixture was then stirred at 100°C under nitrogen for 6 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (eluting with a mixed solvent of ethyl acetate and hexane) to obtain the following formula (DB-25-1) in 80% yield. For the second step of the synthesis scheme below, the reaction was carried out in the same manner as in Synthesis Example 1-15, except that 3,5-dinitrobenzyl chloride was replaced with intermediate (DB-25-1) in the first step of the synthesis scheme in Synthesis Example 1-15, and intermediate (DB-25-2) was obtained. The intermediate (DB-25-2) (5.0 mmol) and 5% Pd / C (0.32 g) were added to a mixed solvent of THF (8 mL) and ethanol (8 mL), and the mixture was stirred under nitrogen at 0°C for 10 minutes. Next, hydrazine monohydrate (30.0 mmol) was added dropwise to the stirring reaction mixture, and stirring was continued at 0°C for 30 minutes. After that, the mixture was stirred under nitrogen at 66°C for 6 hours. After the reaction was complete, the reaction solution was filtered through Celite, ethyl acetate was added, and the mixture was separated and washed with water. Compound (DB-25) was obtained in 80% yield by concentrating the organic phase under reduced pressure. [ka]

[0182] [Synthesis Example 1-18] Synthesis of compound (DB-26) 10.0 mmol of 2-methoxyphenothiazine and 20.0 mmol of sodium hydroxide were added to 20 mL of DMSO and stirred under nitrogen at room temperature for 15 minutes. Then, 100 mmol of iodomethane was added dropwise. The mixture was then stirred at 65°C for 9 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DB-26-1) in 90% yield. Intermediate (DB-26-1) (9.0 mmol) was added to dichloromethane (18 mL) and stirred under nitrogen at 0°C for 15 minutes. Then, boron tribromide (13.5 mL of 1 M dichloromethane solution) was added dropwise. After that, the mixture was stirred under nitrogen at 0°C for 2 hours, and after raising the temperature to room temperature, stirring was continued for a further 10 hours. After the reaction was complete, water was added, neutralized with saturated sodium bicarbonate aqueous solution, and liquid-liquid extraction was performed with dichloromethane. The organic phase was concentrated under reduced pressure and dried to obtain the compound represented by the following formula (DB-26-2) in 95% yield. Intermediate (DB-26-2) (8.6 mmol) and potassium carbonate (17.1 mmol) were added to DMF (15 mL) and stirred at room temperature under nitrogen for 30 minutes. Next, intermediate (DB-26-1) (8.6 mmol), dissolved in DMF (5 mL), was added to the stirring reaction mixture and stirred at 100°C under nitrogen for 6 hours. After the reaction was complete, ethyl acetate was added and the mixture was separated and washed with water. The organic phase was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (elution with a mixed solvent of ethyl acetate and hexane) to obtain the compound represented by the following formula (DB-26-3) in 80% yield. Regarding the fourth step of the synthesis scheme below, the reaction was carried out in the same manner as in Synthesis Example 1-17, except that intermediate (DB-25-2) was changed to intermediate (DB-26-3) in the third step of the synthesis scheme in Synthesis Example 1-17, and intermediate (DB-26) was obtained. [ka]

[0183] [Synthesis Example 1-19] Synthesis of compound (DB-27) Compound (DB-27) was obtained by the same method as in Synthesis Example 1-18, except that the intermediate (DB-25-1) in the third step of the synthesis scheme was changed to 2,4-dinitrofluorobenzene.

[0184] [Synthesis Example 1-20] Synthesis of Compound (DB-28) Compound (DB-28) was obtained by the same method as in Synthesis Example 1-6, except that compound (DA-6-1) was replaced with phenothiazine in the first step of the synthesis scheme in Synthesis Example 1-6.

[0185] <Synthesis of polymers> 1. Synthesis of polyamic acids [Synthesis Example 2-1] 100 moles of compound (c-1) as a tetracarboxylic dianhydride, and 60 moles of compound (DA-1), 10 moles of compound (DB-20), and 30 moles of compound (b-13) as diamine compounds were dissolved in N-methyl-2-pyrrolidone (NMP), and the reaction was carried out at room temperature for 6 hours to obtain a solution containing 15% by mass of polyamic acid (referred to as polymer (PAA-1)).

[0186] [Synthesis Examples 2-2 to 2-34, 2-38 to 2-41] The same procedure as in Synthesis Example 2-1 was followed, except that the types and amounts of tetracarboxylic dianhydride and diamine compounds used were changed as shown in Table 1 or Table 2, to obtain a solution containing polyamic acid (polymers (PAA-2) to (PAA-38)).

[0187] 2. Synthesis of polyimides [Synthesis Example 2-35] A solution containing 20% ​​by mass of polyamic acid was obtained by dissolving 30 mole parts of compound (b-14) and 70 mole parts of compound (b-15) as diamine compounds in N-methyl-2-pyrrolidone (NMP), adding 50 mole parts of compound (c-1) and 50 mole parts of compound (c-4) as tetracarboxylic dianhydrides, and reacting at 40°C for 24 hours. Next, NMP was added to the obtained polymer solution to make a 10% by mass polyamic acid solution, and pyridine and acetic anhydride were added to carry out a dehydration and cyclization reaction at 90°C for 4 hours. After the dehydration and cyclization reaction, the solvent in the system was replaced with fresh NMP to obtain a solution containing 15% by mass of polyimide (referred to as polymer (PI-1)) with an imidization rate of approximately 60%.

[0188] [Synthesis examples 2-36, 2-37, 2-42, 2-43] The same procedure as in Synthesis Example 2-35 was followed, except that the types and amounts of tetracarboxylic dianhydride and diamine compounds used were changed as shown in Table 1 or Table 2, to obtain a solution containing polyimide (polymer (PI-2) to (PI-5)).

[0189] [Table 1]

[0190] [Table 2]

[0191] 3. Synthesis of styrene-maleimide copolymers [Synthesis Example 3-1] Under nitrogen, 5.00 g of compound (M-1), 1.05 g of compound (M-2), 4.80 g of compound (M-3), and 2.26 g of compound (M-4) were added to a 100 mL two-necked flask as polymerization monomers, 0.39 g of 2,2'-azobis(2,4-dimethylvaleronitrile) as a radical polymerization initiator, 0.39 g of 2,4-diphenyl-4-methyl-1-pentene as a chain transfer agent, and 52.5 ml of N-methyl-2-pyrrolidone (NMP) as a solvent. Polymerization was carried out at 70°C for 6 hours. After reprecipitation in methanol, the precipitate was filtered and vacuum-dried at room temperature for 8 hours to obtain a styrene-maleimide copolymer (referred to as polymer (MI-1)). The weight-average molecular weight Mw, measured in polystyrene equivalent by GPC, was 30000, and the molecular weight distribution Mw / Mn was 2.

[0192] [Synthesis Example 3-2] Under nitrogen, 10 moles of compound (M-5), 10 moles of compound (M-6), 30 moles of compound (M-7), 10 moles of compound (M-8), 20 moles of compound (M-9), and 20 moles of compound (M-10) were added to a 100 mL two-necked flask as polymerization monomers, 2 moles of 2,2'-azobis(2,4-dimethylvaleronitrile) as a radical polymerization initiator, and 50 ml of tetrahydrofuran as a solvent. Polymerization was carried out at 70°C for 6 hours. After reprecipitation in methanol, the precipitate was filtered and vacuum-dried at room temperature for 8 hours to obtain a styrene-maleimide copolymer (referred to as polymer (MI-2)). The weight-average molecular weight Mw, measured in polystyrene equivalent by GPC, was 92700, and the molecular weight distribution Mw / Mn was 4.78.

[0193] <Preparation and evaluation of liquid crystal alignment agents> [Example 1: Optical FFS type liquid crystal display element] 1. Preparation of liquid crystal alignment agent To a solution containing polymer (PAA-1) obtained in Synthesis Example 2-1, a solution containing polymer (PAA-35) obtained in Synthesis Example 2-38 was added so that the solid content ratio was polymer (PAA-1):polymer (PAA-35) = 60:40 (mass ratio). The solution was then diluted with NMP, GBL, and BC to obtain a solution with a solvent composition ratio of NMP:GBL:BC = 45:30:25 (mass ratio) and a solid content concentration of 3.5% by mass. This solution was filtered through a 0.2 μm pore size filter to prepare the liquid crystal alignment agent (AL-1).

[0194] 2. Manufacturing of FFS-type liquid crystal cells using photoalignment method A glass substrate (referred to as the first substrate) was prepared, on which a flat electrode (bottom electrode), an insulating layer, and a comb-shaped electrode (top electrode) were laminated in that order on one side, and a glass substrate (referred to as the second substrate) without electrodes was prepared. Next, a liquid crystal alignment agent (AL-1) was applied to the electrode-forming surface of the first substrate and one side of the second substrate using a spinner, and heated on an 80°C hot plate for 1 minute (pre-bake). After that, it was dried (post-bake) in a 230°C oven with nitrogen purging for 30 minutes to form a coating with an average film thickness of 0.1 μm. The obtained coating was exposed to 4,000 J / m of ultraviolet light containing linearly polarized 254 nm emission lines using an Hg-Xe lamp. 2 The substrate was irradiated from the direction normal to the substrate to perform photoalignment treatment. The irradiation dose was measured using a light meter that measures at a wavelength of 254 nm. Next, the photoaligned coating was heat-treated by heating it in a clean oven at 230°C for 30 minutes to form a liquid crystal alignment film. Next, on one of the pair of substrates on which the liquid crystal alignment film was formed, an epoxy resin adhesive containing 3.5 μm diameter aluminum oxide spheres was screen printed onto the outer edge of the surface with the liquid crystal alignment film. Then, the substrates were stacked and pressed together so that the projection direction of the polarization axis onto the substrate surface during light irradiation was antiparallel, and the adhesive was heat-cured at 150°C for 1 hour. Subsequently, negative liquid crystal (Merck, MLC-6608) was filled between the pair of substrates through the liquid crystal injection port, and the liquid crystal injection port was sealed with epoxy adhesive to obtain an optical FFS type liquid crystal cell. Furthermore, to remove the flow orientation during liquid crystal injection, this was heated at 120°C and then slowly cooled to room temperature. The above series of operations was performed with a post-bake UV irradiation dose of 100 to 10,000 J / m². 2 By varying the exposure levels within the specified range, we manufactured three or more liquid crystal cells with different UV irradiation levels, and then evaluated the liquid crystal cell that exhibited the best orientation characteristics (optimal exposure level).

[0195] 3. Evaluation (1) DC afterimage characteristics at room temperature The liquid crystal cell manufactured in step 2 above was placed in an environment of 25°C and 1 atmosphere. After driving it with a 30Hz AC square wave (AC) at a relative transmittance of 100% and setting the brightness difference between any two pixels to 0, the brightness was set to 5000 cd / m². 2 Under backlight illumination, the liquid crystal cell was AC-driven, and a DC (direct current) of 0.5V was applied to only one pixel for 60 minutes to accumulate charge. When the application of DC 0.5V was terminated and the system was returned to AC-only operation, resulting in a relative transmittance of 50%, a brightness difference (defined as ΔL1) was created between the two pixels due to the accumulated charge. The change in this brightness difference ΔL1 over time was observed, and the time it took for the brightness difference ΔL1 to fall below 36.8% of its initial value after the application of DC 0.5V was terminated was defined as the afterimage erasure time. The shorter this time, the faster the accumulated charge in that liquid crystal cell dissipates, resulting in easier afterimage erasure and indicating good DC afterimage characteristics. The evaluation was as follows: afterimage erasure time of less than 10 minutes was rated as "very good (◎)", 10 minutes or more but less than 20 minutes was rated as "good (○)", 20 minutes or more but less than 30 minutes was rated as "acceptable (△)", and 30 minutes or more was rated as "poor (×)". As a result, this example received a "very good (◎)" rating.

[0196] (2) DC afterimage characteristics at 60°C The liquid crystal cell manufactured in step 2 above was placed in an environment of 60°C and 1 atmosphere. After driving it with a 30Hz AC square wave at 100% relative transmittance and setting the brightness difference between any two pixels to 0, the brightness was set to 5000 cd / m². 2Under backlight illumination, the LCD was AC-driven, and a DC (direct current) of 0.1V was applied to only one pixel for 60 minutes to accumulate charge. When the DC 0.1V application was terminated and the system was returned to AC-only operation, resulting in a relative transmittance of 50%, a brightness difference (defined as ΔL2) was created between the two pixels due to the accumulated charge. As a general trend, charge tends to accumulate more easily in liquid crystal cells at higher temperatures than at room temperature. Therefore, to compare the ease of charge accumulation of liquid crystal cells between samples under more stringent conditions, the ease of charge accumulation of each liquid crystal element was evaluated by reflecting the initial amount of accumulated charge in a high-temperature environment (short-term afterimage evaluation). The smaller the brightness difference ΔL2, the less likely the liquid crystal cell is to accumulate charge, indicating better performance. The luminance difference ΔL2 divided by the average luminance of the two pixels was rated as "Excellent (◎)" if it was less than 1%, "Good (○)" if it was between 1% and 2%, "Acceptable (△)" if it was between 2% and 3%, and "Poor (×)" if it was 3% or more. As a result, this example received an evaluation of "Excellent (◎)".

[0197] (3) Evaluation of liquid crystal alignment The liquid crystal cells manufactured in step 2 above were observed under a microscope at 50x magnification to check for the presence or absence of abnormal domains in the change in brightness when a 5V voltage was turned ON and OFF (applied and released). The evaluation was "good" if no abnormal domains were observed and "poor" if abnormal domains were observed. As a result, this embodiment was evaluated as "good".

[0198] (4) Evaluation of inkjet coating properties As the substrate to which the liquid crystal alignment agent was applied, a glass substrate with transparent electrodes made of ITO was heated on a hot plate at 200°C for 1 minute, and then washed with ultraviolet / ozone to reduce the water contact angle on the transparent electrode surface to 10° or less. The liquid crystal alignment agent (AL-1) prepared in 1. above was applied to the transparent electrode surface of the glass substrate with transparent electrodes using an inkjet coating machine (manufactured by Shibaura Mechatronics Co., Ltd.). The application conditions were 2,500 strokes / (nozzle·minute), with a discharge rate of 250 mg / 10 seconds, and applied in two passes (a total of four passes). After application, the substrate was left to stand for 1 minute and then heated at 80°C to form a coating with an average film thickness of 0.1 μm. The number of unevenness and bleeds in the obtained coating was observed with the naked eye under irradiation with an interference fringe measurement lamp (sodium lamp). The results were evaluated as follows: "Excellent (◎)" if the total number of uneven and repelled areas was 0, "Good (○)" if the total number of uneven and repelled areas was 1 or more but less than 3, and "Poor (×)" if the total number of uneven and repelled areas was 3 or more. It should be noted that good polymer solubility tends to improve inkjet coating properties. As a result, the inkjet coating properties of the liquid crystal alignment agent in this example were evaluated as "Excellent (◎)".

[0199] [Examples 2-10, 13-19, 21-35 and Comparative Examples 1-4] Liquid crystal alignment agents were prepared in the same manner as in Example 1, except that the composition of the liquid crystal alignment agent was changed as shown in Table 3. Furthermore, using the obtained liquid crystal alignment agent, optical FFS type liquid crystal cells were manufactured in the same manner as in Example 1, and various evaluations were performed. The results are shown in Table 4.

[0200] [Example 11: Rubbing FFS type liquid crystal display element] 1. Preparation of liquid crystal alignment agent To a solution containing the polymer (PAA-11) obtained in Synthesis Example 2-11, a solution containing the polymer (PAA-38) obtained in Synthesis Example 2-41 was added so that the solid content ratio was polymer (PAA-11):polymer (PAA-38) = 60:40 (by mass). Further, 10 parts by mass of additive (AD-1) were added for every 100 parts by mass of the total polymer (PAA-11) and polymer (PAA-38). By diluting this with NMP, NEP, and BC, a solution with a solid content concentration of 4.0% by mass and a solvent composition ratio of NMP:NEP:BC = 25:55:20 (by mass) was obtained. Liquid crystal alignment agent (AL-11) was prepared by filtering this solution through a pore size filter of 0.2 μm.

[0201] 2. Manufacturing of FFS-type liquid crystal cells using the rubbing method A first substrate and a second substrate were prepared in the same manner as in Example 1. Next, a liquid crystal alignment agent (AL-11) was applied to the electrode formation surface of the first substrate and one side of the second substrate using a spinner, and heated on a hot plate at 110°C for 3 minutes (pre-bake). After that, drying was performed in a 230°C oven with nitrogen purging for 30 minutes (post-bake) to form a coating film with an average thickness of 0.08 μm. Next, the coating film surface was rubbed using a rubbing machine with a roll wrapped in rayon cloth at a roll rotation speed of 1000 rpm, a stage movement speed of 3 cm / sec, and a pile insertion length of 0.3 mm. After that, ultrasonic cleaning was performed in ultrapure water for 1 minute, and then drying in a 100°C clean oven for 10 minutes to obtain a pair of substrates having a liquid crystal alignment film. Next, for a pair of substrates having a liquid crystal alignment film, an epoxy resin adhesive containing 3.5 μm diameter aluminum oxide spheres was screen-printed and applied, leaving a liquid crystal injection port at the edge of the surface where the liquid crystal alignment film was formed. Then, the substrates were stacked and pressed together, and the adhesive was heat-cured at 150°C for 1 hour. Next, negative liquid crystal (Merck MLC-6608) was filled into the gap between the pair of substrates through the liquid crystal injection port, and the liquid crystal injection port was sealed with epoxy adhesive. Furthermore, to eliminate the flow orientation during liquid crystal injection, this was heated to 120°C and then slowly cooled to room temperature to manufacture a liquid crystal cell (rubbing FFS type liquid crystal cell). When stacking the pair of substrates, the rubbing methods of each substrate were made to be opposite parallel.

[0202] 3. Evaluation Using the liquid crystal alignment agent prepared in 1. above and the liquid crystal cell manufactured in 2. above, various evaluations were performed in the same manner as in Example 1. The evaluation results are shown in Table 4.

[0203] [Examples 12, 20, 36] Liquid crystal alignment agents were prepared in the same manner as in Example 11, except that the composition of the liquid crystal alignment agent was changed as shown in Table 3. Furthermore, using the obtained liquid crystal alignment agent, rubbing FFS type liquid crystal cells were manufactured in the same manner as in Example 11, and various evaluations were performed. The evaluation results are shown in Table 4.

[0204] [Comparative Examples 1A to 4A] Rubbing FFS type liquid crystal cells were manufactured in the same manner as in Example 11, except that AR-1 to AR-4 listed in Table 3 were used as liquid crystal alignment agents, and various evaluations were performed. As a result, Comparative Examples 1A to 4A showed results equivalent to those of Comparative Examples 1 to 4 (optical FFS type liquid crystal display elements).

[0205] [Table 3]

[0206] [Table 4]

[0207] [Example 37: Optical Vertical Liquid Crystal Display Element] 1. Preparation of liquid crystal alignment agent To a solution containing the polymer (PAA-1) obtained in Synthesis Example 2-1, the polymer (MI-1) obtained in Synthesis Example 3-1 was added in a ratio of 5 parts by mass of polymer (MI-1) to 95 parts by mass of polymer (PAA-1) on a solid content basis. The solution was then diluted with NMP, GBL, DEDG, and DIBK to obtain a solution with a solid content concentration of 3.5% by mass and a solvent composition ratio of NMP:GBL:DEDG:DIBK = 20:30:40:10 (by mass). This solution was filtered through a 0.2 μm pore size filter to prepare the liquid crystal alignment agent (AL-37).

[0208] 2. Manufacturing of vertical optical liquid crystal cells (UV2A) The liquid crystal alignment agent (AL-37) prepared in step 1 above was applied to the transparent electrode surface of a glass substrate with a transparent electrode made of an ITO film using a spinner, and pre-baked on a hot plate at 80°C for 1 minute. Then, it was heated in an oven with nitrogen purging at 230°C for 1 hour to form a coating with a thickness of 0.1 μm. Next, the surface of this coating was exposed to polarized ultraviolet light containing a 313 nm emission line at 1,000 J / m using an Hg-Xe lamp and a Gran-Taylor prism. 2 The substrate was irradiated from a direction tilted 40° from the substrate normal to impart liquid crystal alignment capability. The same operation was repeated to create a pair (2 substrates) of substrates with a liquid crystal alignment film. An epoxy resin adhesive containing 3.5 μm diameter aluminum oxide spheres was screen printed onto the outer periphery of one of the substrates having a liquid crystal alignment film. Then, the liquid crystal alignment film surfaces of the pair of substrates were placed facing each other, and they were pressed together so that the projection direction of the ultraviolet light axis of each substrate onto the substrate surface was opposite parallel. The adhesive was then heat-cured at 150°C for 1 hour. Next, negative liquid crystal (Merck MLC-6608) was filled into the gap between the substrates through the liquid crystal injection port, and the liquid crystal injection port was sealed with epoxy adhesive. Furthermore, to remove the flow orientation during liquid crystal injection, it was heated at 130°C and then slowly cooled to room temperature.

[0209] 3. Evaluation The liquid crystal alignment agent prepared in 1. above and the liquid crystal cell manufactured in 2. above were used to perform various evaluations in the same manner as in Example 1. The evaluation results are shown in Table 6.

[0210] [Comparative Example 5] A liquid crystal alignment agent was prepared in the same manner as in Example 37, except that the composition of the liquid crystal alignment agent was changed as shown in Table 5. Furthermore, a vertical-optical liquid crystal cell was manufactured using the obtained liquid crystal alignment agent in the same manner as in Example 37, and various evaluations were performed. The evaluation results are shown in Table 6.

[0211] [Table 5]

[0212] [Table 6]

[0213] [Example 38: PSA-type liquid crystal display element] 1. Preparation of liquid crystal alignment agent To a solution containing the polymer (PI-2) obtained in Synthesis Example 2-36, the polymer (MI-2) obtained in Synthesis Example 3-2 was added so that the ratio of polymer (MI-2) to polymer (PI-2) was 5 parts by mass, on a solid content basis. The solution was then diluted with NMP and BC to obtain a solution with a solvent composition of NMP / BC = 50 / 50 (mass ratio) and a solid content concentration of 3.5% by mass. This solution was filtered through a 0.2 μm pore size filter to prepare the liquid crystal alignment agent (AL-38).

[0214] 2. Manufacturing of PSA-type liquid crystal cells (1) Preparation of liquid crystal composition To 10 g of nematic liquid crystal (Merck, MLC-6608), 5% by mass of a liquid crystalline compound represented by the following formula (L1-1) and 0.3% by mass of a photopolymerizable compound represented by the following formula (L2-1) were added and mixed to obtain liquid crystal composition LC1. [ka]

[0215] (2) Manufacturing of liquid crystal cells The liquid crystal alignment agent (AL-38) prepared above was applied to the transparent electrode surface of a glass substrate with a transparent electrode made of ITO film using a spinner. After pre-baking on an 80°C hot plate for 1 minute, the solvent was removed by heating in a nitrogen-purged oven at 200°C for 1 hour to form a coating film (liquid crystal alignment film) with a thickness of 0.08 μm. This coating film was then rubbed using a rubbing machine with a roll wrapped in rayon cloth at a roll rotation speed of 400 rpm, a stage movement speed of 3 cm / second, and a pile insertion length of 0.1 mm. Subsequently, ultrasonic cleaning was performed in ultrapure water for 1 minute, and then drying in a 100°C clean oven for 10 minutes to obtain a substrate with a liquid crystal alignment film. This operation was repeated to obtain a pair (2 sheets) of substrates with a liquid crystal alignment film. This rubbing process was a weak rubbing process performed to control the tilting of the liquid crystals and to perform alignment division in a simple manner. An epoxy resin adhesive containing aluminum oxide spheres with a diameter of 3.5 μm was screen printed onto the outer periphery of one of the substrates having a liquid crystal alignment film. Then, the liquid crystal alignment film surfaces of the pair of substrates were placed facing each other, overlapped, and pressed together. The adhesive was then heat-cured at 150°C for 1 hour. Next, the liquid crystal composition LC1 was filled into the gap between the substrates through the liquid crystal injection port, the liquid crystal injection port was sealed with an epoxy adhesive, and then, to remove the flow orientation during liquid crystal injection, it was heated at 150°C for 10 minutes and then slowly cooled to room temperature. Next, a 10V AC current with a frequency of 60Hz is applied between the electrodes of the obtained liquid crystal cell, and while the liquid crystal is in operation, ultraviolet light of 50,000 J / m² is irradiated using an ultraviolet irradiation device with a metal halide lamp as the light source. 2 The irradiation was performed at the specified dose. This dose was measured using a light meter that measures at a wavelength of 365 nm. A PSA-type liquid crystal cell was manufactured using this method.

[0216] 3. Evaluation Using the liquid crystal alignment agent prepared in 1. above and the liquid crystal cell manufactured in 2. above, various evaluations were performed in the same manner as in Example 1. The evaluation results are shown in Table 8.

[0217] [Comparative Example] 6 ] Liquid crystal alignment agents were prepared in the same manner as in Example 38, except that the composition of the liquid crystal alignment agent was changed as shown in Table 7. Furthermore, PSA-type liquid crystal cells were manufactured using the obtained liquid crystal alignment agents in the same manner as in Example 38, and various evaluations were performed. The evaluation results are shown in Table 8.

[0218] [Table 7]

[0219] [Table 8]

[0220] As shown in Tables 4, 6, and 8, Examples 1 to 38, which used liquid crystal alignment agents containing polymer (P), exhibited superior liquid crystal alignment properties compared to Comparative Examples 1 to 6, which used liquid crystal alignment agents without polymer (P), while also demonstrating excellent DC afterimage characteristics at room temperature (i.e., relaxation characteristics of accumulated charge) and DC afterimage characteristics at 60°C (i.e., resistance to charge accumulation). Furthermore, the liquid crystal alignment agents of Examples 1 to 38 also exhibited excellent inkjet coating properties.

[0221] From these results, it has become clear that a liquid crystal alignment agent containing polymer (P) can be used to obtain a liquid crystal element that exhibits good coating properties, excellent liquid crystal alignment, low charge accumulation, and rapid residual charge relaxation.

Claims

1. A polymer (P) which is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide, The polymer (P) is a liquid crystal alignment agent that contains the following structural unit (UA) and structural unit (UB) within the same molecule, or contains the following structural unit (UA) and structural unit (UB) within different molecules. Structural Unit (UA): A structural unit derived from at least one selected from the group consisting of diamine compounds having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C (DA-1), and diamine compounds having a quinone structure (DA-2). Structural Unit (UB): A structural unit derived from at least one selected from the group consisting of a diamine compound having a substructure represented by the following formula (b1) (DB-1) and a diamine compound having a phenothiazine structure (DB-2). 【Chemistry 1】 (In formula (b1), X １ , B １ and X ２ The following conditions [i] or [ii] are met. "*" represents a combination. [i] X １ is an aromatic ring group. B １ is -NY ３ - or an aromatic heterocyclic group. X ２ and Y ３ are such that X ２ is an aromatic ring group and Y ３ is a hydrogen atom or a monovalent organic group, or X ２ and Y ３ are combined with each other to represent a nitrogen-containing condensed ring structure formed by the nitrogen atom to which X ２ and Y ３ are attached. However, the nitrogen-containing condensed ring structure has an aromatic ring, and the nitrogen atom in B １ is bonded to the aromatic ring in the nitrogen-containing condensed ring structure. [ii] B １ Ha - NY ３ - is Y ３ X is a hydrogen atom or a monovalent organic group. １ and X ２ X is formed by combining them with each other. １ and X ２ This represents a nitrogen-containing condensed ring structure formed together with the nitrogen atom to which it is bonded. However, the nitrogen-containing condensed ring structure has multiple aromatic rings, and B １ The nitrogen atom inside links the two aromatic rings in the nitrogen-containing condensed ring structure.

2. The liquid crystal alignment agent according to claim 1, wherein the diamine compound (DA-1) is a compound represented by the following formula (a1-1). 【Chemistry 2】 (In formula (a1-1), A １ This is a group having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are replaced by electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C. １ Ar is a single bond or a (n1+1) valence linking group. １ (This is an aromatic ring group. n1 is either 1 or 2.)

3. The liquid crystal alignment agent according to claim 1, wherein the diamine compound (DA-2) is at least one selected from the group consisting of compounds represented by the following formula (a2-1) and compounds represented by the following formula (a2-2). 【Transformation 3】 (In formula (a2-1), A ２ R is a group that has a quinone structure. ２ Ar is a single bond or a (n²+1) valence linking group. ２ It is an aromatic ring group. n2 is either 1 or 2. In formula (a2-2), A ３ R is a group that has a quinone structure. ３ and R ４ Each of these is independently a single bond or a divalent organic group. ３ and Ar ４ These are each independent aromatic ring groups.

4. The liquid crystal alignment agent according to claim 1, wherein the diamine compound (DB-2) is a compound represented by the following formula (b2-1). 【Chemistry 4】 (In formula (b2-1), A ４ R is a group having a phenothiazine structure. ５ Ar is a single bond or a (n3+1) valence linking group. ５ (This is an aromatic ring group. n3 is either 1 or 2.)

5. The liquid crystal alignment agent according to claim 1, wherein the polymer (P) further comprises structural units (UC) derived from a diamine compound having a substructure represented by the following formula (2). 【Transformation 5】 (In formula (2), X ５ and X ６ These are each an independent aromatic ring group. ７ and R ８ Each of these is independently a single bond, a carbon-1 to carbon-10 alkanediyl group, or a carbon-1 to carbon-10 substituted alkanediyl group. ５ and Y ６ Each of them is independent of the others, * ４ -NR ９ -CO- or * ４ -CO-NR ９ - is R ９ is a hydrogen atom or a monovalent organic group. ４ " is Z ５ This represents a combination with Z. ５ is a single bond or a divalent organic group. m is 0 or 1. If m is 0, R ７ , R ８ Alternatively, both of these are alkanediyl groups or substituted alkanediyl groups having 1 to 10 carbon atoms. (* indicates a bond.)

6. The liquid crystal alignment agent according to claim 1, wherein the electron-withdrawing group is at least one selected from the group consisting of a halogen atom, a cyano group, an alkyl halide, and an acyl group.

7. The liquid crystal alignment agent according to claim 1, further comprising a polymer (Q) having neither of the following substructures (A) and (B). Substructure (A): At least one selected from the group consisting of a substituted heterocyclic structure, a quinone structure, and a tetracyanoquinodimethane structure, in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are replaced by electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C. Substructure (B): At least one selected from the group consisting of the substructure represented by the above formula (b1) and the phenothiazine structure.

8. The liquid crystal alignment agent according to claim 7, wherein the polymer (Q) is at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, and addition polymer.

9. A liquid crystal alignment film formed using the liquid crystal alignment agent described in any one of claims 1 to 8.

10. A liquid crystal element comprising the liquid crystal alignment film described in claim 9.

11. A polymer comprising a polyamic acid, a polyamic acid ester, or a polyimide, which contains the following structural units (UA) and (UB) within the same molecule. Structural Unit (UA): A structural unit derived from at least one selected from the group consisting of diamine compounds having a substituted heterocyclic structure in which one or more hydrogen atoms bonded to a nitrogen-containing aromatic heterocyclic ring are substituted with electron-withdrawing groups that do not leave the ring when heated at temperatures below 230°C (DA-1), and diamine compounds having a quinone structure (DA-2). Structural Unit (UB): A structural unit derived from at least one selected from the group consisting of a diamine compound having a substructure represented by the following formula (b1) (DB-1) and a diamine compound having a phenothiazine structure (DB-2). 【Transformation 6】 (In formula (b1), X １ , B １ and X ２ It satisfies either [i] or [ii] below. [i]X １ This is an aromatic ring group. B １ is, -NY ３ - Or it is an aromatic heterocyclic group. X ２ and Y ３ is, X ２ is an aromatic ring group, Y ３ is a hydrogen atom or a monovalent organic group, or X ２ and Y ３ and are combined to form X ２ and Y ３ This represents a nitrogen-containing condensed ring structure formed together with the nitrogen atom to which it is bonded. However, the nitrogen-containing condensed ring structure has an aromatic ring, and B １ The nitrogen atoms inside are bonded to the aromatic ring in the nitrogen-containing condensed ring structure. [ii] B １ Ha - NY ３ - is Y ３ X is a hydrogen atom or a monovalent organic group. １ and X ２ X is formed by combining them with each other. １ and X ２ This represents a nitrogen-containing condensed ring structure formed together with the nitrogen atom to which it is bonded. However, the nitrogen-containing condensed ring structure has multiple aromatic rings, and B １ The nitrogen atom inside links the two aromatic rings in the nitrogen-containing condensed ring structure. The asterisk (*) represents a bonding operation.

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