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

Abstract

The present invention provides a liquid crystal alignment agent containing a polymer component, wherein the polymer component meets at least one of the following conditions (i) and (ii). Condition (i): The aforementioned polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) and a repeating unit (a1') represented by formula (1') and a polyimide consisting of a polyimide of the polyimide precursor. Condition (ii): The aforementioned polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and a polyimide consisting of a polyimide of a polyimide precursor with a amide. X 1. and X 1' represents a tetravalent organogroup independently. Y 1 indicates a divalent organogroup with an acetazoline skeleton. Y 1' represents a divalent organic group (Ah) with an aliphatic carboxyl group or a divalent organic group (ph) with a phenolic hydroxyl group. R and Z each independently represent a hydrogen atom or a monovalent organic group.

Description

Technical Field

[0001] This invention relates to a liquid crystal alignment agent, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element having the liquid crystal alignment film. Prior Technology

[0002] In the past, various driving methods have been developed for liquid crystal display elements, including different electrode structures and the physical properties of the liquid crystal molecules used. Examples include known TN (Twisted Nematic), STN (Super Twisted Nematic), VA (Vertical Alignment), IPS (In-Plane Switching), and FFS (Fringe Field Switching) display elements. These liquid crystal display elements have a liquid crystal alignment film to align the liquid crystal molecules. Known materials for the liquid crystal alignment film include polyamide, polyamide ester, polyimide, and polyamide. VA-type liquid crystal display elements, which are one of the driving methods of liquid crystal display elements, are known to be technology that involves adding photopolymerizable compounds to the liquid crystal composition in advance and using a vertical alignment film such as polyimide to apply voltage to the liquid crystal cells while irradiating them with ultraviolet light to accelerate the response speed of the liquid crystal (PSA (Polymer Sustained Alignment) type element) (see, for example, Patent Document 1 and Non-Patent Document 1).

[0003] In recent years, large-screen and high-resolution LCD TVs have become widely used. For such applications, LCD elements, compared to those used in displays primarily for text and static images, require the ability to withstand long-term use in harsh environments. The liquid crystal alignment film used in this context needs to be more reliable than previous versions. For example, regarding the electrical characteristics of the liquid crystal alignment film, known as voltage retention rate, not only must the initial characteristics be good, but it must also maintain good characteristics after prolonged exposure to high temperature and humidity. Patent Document 2 proposes a polyimide-based liquid crystal alignment film with an azirzoline backbone to address these challenges. [Previous Technical Documents] [Patent Literature]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2003-307720 [Patent Document 2] International Publication No. 2019 / 054443 [Non-patent literature]

[0005] [Non-Patent Literature 1] K. Hanaoka, SID 04 DIGEST, P1200-1202 Summary of the Invention

[0006] [The problem the invention aims to solve]

[0007] Furthermore, the demand for lower cost of liquid crystal display (LCD) components is currently higher than ever before, and various materials are gradually being used in the liquid crystal materials used in LCD components. In particular, when using low-cost liquid crystal materials, the probability of voltage retention degradation in LCD components increases, requiring liquid crystal alignment films with higher voltage retention rates than before.

[0008] In view of the above, the object of the present invention is to provide a liquid crystal alignment agent that can obtain a high voltage retention rate even after long-term exposure to high temperature and high humidity, a liquid crystal alignment film obtained by the liquid crystal alignment agent, and a liquid crystal display element using the film. [Methods for solving problems]

[0009] In order to achieve the above-mentioned objectives, the inventors of this invention conducted extensive research and discovered that liquid crystal alignment agents containing specific components are effective in achieving the above objectives, thus completing this invention.

[0010] This invention is based on this knowledge and insight, and its main points are as follows. [1] A liquid crystal alignment agent comprising a polymer component, wherein the polymer component meets at least one of the following conditions (i) and (ii), Condition (i): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having repeating units (a1) and (a1') having repeating units (a1') represented by formula (1) and a polyimide consisting of a polyimide derivative of the polyimide precursor. Condition (ii): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and a polyimide consisting of a amide of the polyimide precursor, and at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by the following formula (1') and a polyimide consisting of a amide of the polyimide precursor, [Chemistry 1] X1 and X1' each independently represent a tetravalent organic group, Y1 represents a divalent organic group with an acezoline skeleton, Y1' represents a divalent organic group with an aliphatic carboxyl group (Ah) or a divalent organic group with a phenolic hydroxyl group (ph), and R and Z each independently represent a hydrogen atom or a monovalent organic group. [2] As in [1], the liquid crystal alignment agent, wherein the divalent organic group (ph) has a structure represented by the following formula (ph-1) as the structure of the phenolic hydroxyl group, [Chemistry 2] Ar represents a benzene ring or a naphthalene ring, R represents a hydrogen atom, a methyl group, a methoxy group, or a halogen atom, and * represents an atomic bond. When Ar is a benzene ring, p represents an integer from 1 to 5, q represents an integer from 0 to 4, and r represents an integer from 1 to 5. The sum of p, q, and r is 6. When Ar is a naphthalene ring, p represents an integer from 1 to 7, q represents an integer from 0 to 6, and r represents an integer from 1 to 7. The sum of p, q, and r is 8. [3] Liquid crystal alignment agents such as [1] or [2], wherein the polymer component at least meets the condition (i). [4] Liquid crystal alignment agents such as [1] or [2], wherein the polymer component at least meets the condition (ii). [5] A liquid crystal alignment agent such as any one of [1] to [4], wherein the oxazoline skeleton in Y1 is located in the main chain of a polymer having Y1. [6] A liquid crystal alignment agent as described in any of [1] to [5], wherein Y1 has a substructure represented by the following formula (m-Ox), and the substructure represented by the formula (m-Ox) is located in the main chain of the polymer having Y1. [Chemistry 3] R 1 represents a hydrogen atom or a monovalent organic group, and * represents an atomic bond. [7] A liquid crystal alignment agent as described in any of [1] to [6], wherein the aliphatic carboxyl group has carbon atoms of the carboxyl group and methylene group bonded together with carbon atoms of an alicyclic structure. [8] A liquid crystal alignment agent as described in any of [1] to [7], wherein the divalent organic group (Ah) is a diamine (Ah) from which two amino groups have been removed. The specific diamine (Ah) is an aromatic diamine represented by "A1'-(L-Ah)m'" or "(A11')2-Ah'". A 1' indicates that there are two primary amino groups bonded to the m' valence group of the aromatic group. A 11' indicates that there is one primary amino group bonded to a monovalent aromatic group. L represents a single bond, -O-, -CO-, -CO-O-, -NR- (R represents a hydrogen atom or a methyl group), or -NR-CO- (R represents a hydrogen atom or a methyl group). Ah represents a monovalent aliphatic carboxyl group. m' is an integer from 1 to 2. Ah' represents a divalent aliphatic carboxyl group. [9] A liquid crystal alignment agent as described in any one of [1] to [8], wherein the polymer component meets at least one of the following conditions (i-1), (ii-1), and (ii-2). Condition (i-1): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1), a repeating unit (a1') represented by formula (1'), and a repeating unit (a2) represented by formula (2), and a polyimide consisting of a polyimide derivative of the polyimide precursor. Condition (ii-1): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) and a repeating unit (a2) represented by formula (2) and a polyimide consisting of a amide of the polyimide precursor, and at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by formula (1') and a polyimide consisting of a amide of the polyimide precursor, Condition (ii-2): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) and a polyimide consisting of a amide of the polyimide precursor, and at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by formula (1') and a repeating unit (a2) represented by formula (2) and a polyimide consisting of a amide of the polyimide precursor, [Chemistry 4] X2 represents a tetravalent organogroup, Y2 represents a divalent organogroup with the radical -XJ, and R and Z each independently represent a hydrogen atom or a monovalent organogroup. In this base -XJ, X represents a single bond, -(CH2)a- (a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH3)-, -NH-, -O-, -COO-, -OCO-, -Ak-O-CO-CH=CH-** (** represents an atomic bond with an aromatic hydrocarbon group, Ak represents a divalent organic group with 1 to 10 carbon atoms), or -(A1)a0-((CH2)a1-A1)m1- (a0 is an integer of 0 or 1, a1 is an integer from 1 to 15, A1 independently represents -O- or -COO-, m1 is an integer from 1 to 2, when m1 is 2, multiple a1 independently have this definition). J represents a monovalent organic group having at least one group selected from the group consisting of alicyclic hydrocarbon groups with 4 to 40 carbon atoms and aromatic hydrocarbon groups with 6 to 40 carbon atoms, wherein at least one of the hydrogen atoms of the alicyclic hydrocarbon group and the aromatic hydrocarbon group is substituted by a halogen atom, an alkyl group with 1 to 10 carbon atoms containing a halogen atom, an alkoxy group with 1 to 10 carbon atoms containing a halogen atom, an alkyl group with 3 to 10 carbon atoms, an alkoxy group with 3 to 10 carbon atoms, or an alkenyl substituent (v) with 3 to 10 carbon atoms, and any carbon-carbon single bond in such substituent (v) (except for the halogen atom) may be interrupted by -O-.

[10] The liquid crystal alignment agent of any one of [1] to [9], wherein the tetravalent organic group in X1 and X1' is a tetravalent organic group derived from tetracarboxylic dianhydride or its derivative, and the tetravalent organic group is a tetravalent organic group derived from acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride, or their derivatives.

[11] A liquid crystal alignment film is obtained from any of the liquid crystal alignment agents described in [1] to

[10] .

[12] A liquid crystal display element having a liquid crystal alignment film as described in

[11] .

[13] A method for manufacturing a liquid crystal display element includes the following steps (1) to (3) in sequence. Step (1): A liquid crystal alignment agent as described in any one of [1] to

[10] is coated onto at least one of a pair of substrates having a conductive film to form a coating film. Step (2): Calcine the coating film. Step (3): A liquid crystal layer is formed between the pair of substrates to create a liquid crystal cell.

[14] The manufacturing method of the liquid crystal display element as described in

[13] includes performing the following step (4) after steps (1) to (3). Step (4): Irradiate the liquid crystal cell with light.

[0011] Furthermore, in this specification, * indicates an atomic bond. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. [Effects of the Invention]

[0012] According to the liquid crystal alignment agent of the present invention, a liquid crystal alignment film with high voltage retention rate can still be obtained even after long-term exposure under high temperature and high humidity. The mechanism by which the above-mentioned effects of the present invention are obtained may not be clear, but it is believed that the following description is one of the reasons. The acetazoline skeleton contained in the polymer used in the present invention (e.g., the structures (s-Ox) and (m-Ox) described later) undergoes ring-opening and cross-linking reaction with the carboxylic acid in acetic acid during post-baking. This ring-opening reaction is promoted by the catalytic effect under acidic conditions. Therefore, by using divalent organic groups (Ah) containing aliphatic carboxyl groups or divalent organic groups (ph) containing phenolic hydroxyl groups, the ring-opening reaction proceeds more readily and cross-links with the carboxylic acid, and the film density of the obtained liquid crystal alignment film is increased. Therefore, it is believed that a liquid crystal alignment film with increased voltage retention rate can be obtained. Implementation

[0013] The following describes the components contained in the liquid crystal alignment agent of this specification, as well as other components that may be added as needed.

[0014] <Polymer Components> The liquid crystal alignment agent of this invention contains a polymer component. The polymer components meet at least one of the following conditions (i) and (ii). Condition (i): The polymer composition contains at least one polymer (P-a1+a1') selected from the group consisting of a polyimide precursor having repeating units (a1) represented by formula (1) and repeating units (a1') represented by formula (1') and a polyimide consisting of a polyimide of the polyimide precursor (also referred to as a copolymer). Condition (ii): The polymer component contains at least one polymer (P-a1) selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) and a polyimide consisting of a polyimide derivative of the polyimide precursor, and at least one polymer (P-a1') selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by formula (1') and a polyimide consisting of a polyimide derivative of the polyimide precursor (hereinafter, a mixture of polymer (P-a1) and polymer (P-a1') is also referred to as a polymer blend. The copolymers and polymer blends described above can be used alone or in combination. Furthermore, in condition (i), the repeating unit (a1) represented by equation (1) and the repeating unit (a1') represented by equation (1') exist within the same molecule of the polymer. Furthermore, the polymer component may also contain at least one polymer selected from the group consisting of a polyimide precursor that does not have the aforementioned repeating unit (a1) or the aforementioned repeating unit (a1') and a polyimide that is a polyimide derivative of the polyimide precursor.

[0015] When the polymer composition contains the copolymer, considering the viewpoint of ideally obtaining the effect of the present invention, the total content of the repeating unit (a1), the repeating unit (a1') and their amide structural units in the copolymer is preferably 5 to 100 mol%, more preferably 10 to 100 mol%, and even more preferably 20 to 100 mol%. Furthermore, considering the viewpoint of ideally obtaining the effects of the present invention, the total content of the repeating unit (a1) and the amide-imino structural unit of the repeating unit (a1) in the above copolymer is preferably 1 to 90 mol%, more preferably 5 to 85 mol%, and more preferably 10 to 80 mol%.

[0016] When the polymer composition contains the polymer blend, the total proportion of the repeating unit (a1) and the amide-imide structural unit of the repeating unit (a1) in the polymer (P-a1) is preferably 1 to 99 mol%, more preferably 2 to 95 mol%, and more preferably 5 to 90 mol% when considering the ideal effect of the present invention. Furthermore, considering the viewpoint of efficiently obtaining the effects of the present invention, the total content of the repeating unit (a1') and the amide-imide structural unit of the repeating unit (a1') in the above polymer (P-a1') is preferably 5 to 90 mol%, and 10 to 80 mol% is more ideal.

[0017] Furthermore, in the aforementioned polymer components, the mass ratio of the content of the aforementioned polymer (P-a1') to the content of the aforementioned polymer (P-a1) ((P-a1) / (P-a1')) is preferably 5 / 95 to 95 / 5, and more preferably 10 / 90 to 90 / 10.

[0018] (Repeating unit (a1)) In formula (1) above, Y1 represents a divalent organic group having an acetazoline skeleton. The acetazoline skeleton only needs to be present in at least one of the main chain and side chain of the polymer. When the acetazoline skeleton in Y1 is located on the side chain of a polymer having Y1, the position of the acetazoline skeleton in the side chain is not particularly limited; it can be in the middle portion or the end portion of the polymer side chain. In the above case, it is preferable that the acetazoline skeleton of Y1 is located at the end portion of the polymer side chain. Furthermore, it is preferable that Y1 has a substructure represented by the following formula (s-Ox). [Chemistry 5] n is an integer from 1 to 3. When n is 1, R represents a single bond, -O-, or an organogroup with a valence of (n+1). When n is 2 or 3, R represents an organogroup with a valence of (n+1).

[0019] In the above formula (s-Ox), the (n+1) valence organic group of R can be listed as -COO-, -CONH-, (n+1) valence hydrocarbon group (acyclic chain hydrocarbon group with (n+1) valence of 1~10 carbons, alicyclic hydrocarbon group with (n+1) valence of 3~10 carbons, aromatic hydrocarbon group with (n+1) valence of 6~18 carbons), (n+1) valence organic group in which at least one methylene group is replaced by a divalent functional group such as -O-, -S-, -CO-, -COO-, -COS-, -NR 1-, -CONR 1- (R 1 is a hydrogen atom or a hydrocarbon group with 1~6 carbons), (n+1) valence organic group in which at least one hydrogen atom of the above hydrocarbon group is replaced by a halogen atom, etc., (n+1) valence organic group in which a heterocyclic organic group is formed, etc.

[0020] A more ideal example of the substructure represented by the above formula (s-Ox) can be listed below, represented by formulas (s-Ox-1) to (s-Ox-5). [Chemistry 6] In the formula, L represents -CONH-, -NHCO-, -CO-N(CH 3)-, -NH-, -O-, -COO-, or -OCO-. n4 is an integer from 0 to 3, and n5 is an integer from 1 to 3.

[0021] When the acezoline skeleton in Y1 is located on the side chain of a polymer having Y1, Y1 is preferably a diamine with two amino groups removed from the substructure represented by the above formula (s-Ox) (hereinafter also referred to as a specific diamine (s-Ox)). Specific examples of the aforementioned specific diamine (s-Ox) are preferably aromatic diamines represented by "A1-(Z1)m" (A1 represents an m-valent group with two primary amino groups bonded to an aromatic group. Specific examples of aromatic ring structures of the aromatic group include benzene rings, naphthyl rings, biphenyl structures, or aromatic ring structures formed by two benzene rings linked by alkyl groups having 1 to 3 carbon atoms. Z1 represents the substructure represented by the above formula (s-Ox). m is an integer from 1 to 2.)

[0022] In the above-mentioned diamine "A1-(Z1)m", when the aromatic group of A1 represents a benzene ring, it is preferable that the two amino groups in the diaminophenyl group are at the 2,5-position or the 3,5-position relative to Z1.

[0023] When the acezoline skeleton in Y1 is located in the main chain of a polymer containing Y1, Y1 preferably has a secondary structure represented by the following formula (m-Ox). [Chemistry 7] R 1 represents a hydrogen atom or a monovalent organic group, and * represents an atomic bond.

[0024] The monovalent organic group in R 1 of the above formula (m-Ox) is preferably a monovalent organic group having an aromatic group (an aromatic ring structure in the aromatic group, such as a benzene ring), a monovalent chain hydrocarbon group having 1 to 10 carbon atoms (such as methyl, ethyl, propyl, etc.), or a monovalent alicyclic hydrocarbon group having 3 to 10 carbon atoms. The aforementioned monovalent organic group having an aromatic group may consist only of an aromatic group, or a portion thereof may contain a chain structure and at least one of the aforementioned alicyclic structures. Furthermore, the aforementioned alicyclic hydrocarbon group may consist only of an alicyclic structure (such as a cyclohexane ring), or a portion thereof may contain a chain structure. Moreover, the at least one hydrogen atom possessed by the aforementioned monovalent organic group having an aromatic group, the aforementioned chain hydrocarbon group, or the aforementioned alicyclic hydrocarbon group may be substituted with a halogen atom, a hydroxyl group, a cyano group, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluoroalkyl group having 1 to 3 carbon atoms, etc. Furthermore, any methylene group of the aforementioned monovalent organic group having an aromatic group, the aforementioned chain hydrocarbon group, or the aforementioned alicyclic hydrocarbon group may be replaced by -O-, -CO-, or -COO-. From the viewpoint of ideally achieving the effects of the present invention, R1 in the above formula (m-Ox) is preferably a hydrogen atom or a methyl group.

[0025] When the acetazoline skeleton in Y1 is located in the main chain of a polymer having Y1, Y1 is preferably a diamine (hereinafter also referred to as a specific diamine (m-Ox)) with two amino groups removed from it, having the structure represented by the above formula (m-Ox). Specific examples of the above-mentioned specific diamine (m-Ox) can be listed as diamines selected from the group represented by the following formulas (m-Ox-1) to (m-Ox-3). [Chemistry 8] R1 is synonymous with R1 in formula (m-Ox). R2 represents a divalent organogroup formed by inserting a single bond, -O-, -COO-, -OCO-, -CONR 11-, -NR 11CO-, -NR 11-, an alkyl group having 1 to 24 carbon atoms, or at least one position between carbon-carbon bonds and at the end of an alkyl group having 1 to 24 carbon atoms, consisting of a group selected from the group consisting of -O-, -COO-, -OCO-, -NR 11-, -CONR 11-, -NR 11CO-, and -NR 11-CO-NR 11-. R11 represents a hydrogen atom or a methyl group. W1 to W2, W4 each independently represent an aromatic hydrocarbon group, and W3 represents an aromatic hydrocarbon group or an alicyclic hydrocarbon group. a is an integer of 0 or 1. In equation (m-Ox-2), multiple R1, W1, and multiple R2 when a is 1 can be the same or different from each other.

[0026] The aromatic hydrocarbon groups in W1 to W4 may consist solely of an aromatic group (an aromatic ring structure within the aromatic group, such as a benzene ring, naphthalene ring, biphenyl structure, anthracene ring, etc.), or may be hydrocarbon groups linked by at least one of a chain structure (e.g., a structure with an alkyl group) and an alicyclic structure (e.g., a cyclohexane ring, etc.). Ideal examples of the aromatic ring structure of the aromatic hydrocarbon groups in W1 to W4 are benzene rings, naphthalene rings, and biphenyl structures. The alicyclic hydrocarbon group in W3 may consist solely of an alicyclic structure, or a portion of it may contain a chain structure. The alicyclic hydrocarbon group in W3 is preferably an alkylcyclohexyl group or an alkylbiscyclohexyl group. Furthermore, a portion of the hydrogen atoms in the aforementioned aromatic hydrocarbon group or alicyclic hydrocarbon group may be substituted by substituents, and any methylene group may be substituted by -O-, -CO-, or -COO-. Examples of substituents include halogen atoms, hydroxyl groups, cyano groups, alkyl groups with 1 to 3 carbon atoms, alkoxy groups with 1 to 3 carbon atoms, fluoroalkyl groups with 1 to 3 carbon atoms, dialkylamino groups (e.g., dimethylamino groups), carboxyamino groups (e.g., acetamino groups, acrylamino groups), etc.

[0027] Regarding the -R 2-W 2- in the above formulas (m-Ox-1) and (m-Ox-3), considering the ideal effect of the present invention, the following formulations are preferred: -(CH 2) nO-Ar 1-, -(CH 2) n-OCO-Ar 1-, -(CH 2) n-NR 11CO-Ar 1-, -(CH 2) n-NR 11-Ar 1- (n is an integer from 1 to 6. Ar 1 represents 1,4-epenylphenyl or 4,4'-biphenyldiyl. R 11 represents a hydrogen atom or a methyl group.) Regarding the -R 2-(W 3-R 2) α- in the above formula (m-Ox-2), considering the ideal effect of the present invention, the preferred formulations are -(CH 2) n-OCO-(CH 2) m-COO-(CH 2) n-, -(CH 2) n-NR 11CO-(CH 2) m-CONR 11-(CH 2) n-, -(CH 2) n-NR 11-CO-NR 11-(CH 2) n-, -(CH 2) n-OCO-Cy-COO-(CH 2) n-, -(CH 2) n-NR 11CO-Cy-CONR 11-(CH 2) n- (n is an integer from 1 to 6. m is an integer from 1 to 12. Cy represents 1,4-epenylphenyl or 1,4-epenylcyclohexyl. R 11 represents a hydrogen atom or a methyl group.) In (m-Ox-3), -W 4-, from the viewpoint of ideally obtaining the effects of the present invention, is preferably 1,4-elongylphenyl.

[0028] (Repeating unit (a1')) In the above formula (1'), Y 1' represents a divalent organic group (Ah) with an aliphatic carboxyl group or a divalent organic group (ph) with a phenolic hydroxyl group.

[0029] (Divalent organogroup (Ah)) Here, an aliphatic carboxyl group is a functional group in which at least one carboxyl group is directly bonded to an aliphatic group. The number of carboxyl groups bonded to the aliphatic group is not particularly limited, but from the perspective of availability, 1 to 8 is preferred. The specific examples of the aforementioned aliphatic groups are not particularly limited as long as they have an aliphatic structure, but it is preferable that they are aliphatic groups formed by carbon atoms of the carboxyl group and methylene group or carbon atoms forming an alicyclic structure. More ideal specific examples of aliphatic groups may include chain hydrocarbon groups with 1 to 30 carbon atoms, or alicyclic hydrocarbon groups with 3 to 30 carbon atoms. Here, "chain hydrocarbon group" refers to a straight-chain hydrocarbon group or a branched hydrocarbon group that does not contain an alicyclic structure. However, chain hydrocarbon groups can be saturated or unsaturated. Furthermore, in the aforementioned chain hydrocarbon groups, at least one of the carbon-carbon bonds or its terminal may contain -O-, -CO-, -CO-O-, -NR- (where R represents a hydrogen atom or a methyl group), or -NR-CO- (where R represents a hydrogen atom or a methyl group). (Hereinafter, these will also be referred to as heteroatom-containing groups.) The aforementioned alicyclic hydrocarbon groups may consist solely of alicyclic structures (e.g., cyclobutane ring, cyclopentane ring, cyclohexane ring, etc.), and some may also contain chain structures. Furthermore, these chain structures may also have heteroatom-containing groups inserted between carbon-carbon bonds. At least one of the hydrogen atoms of the carbon atom constituting the aliphatic group may be replaced by a halogen atom, hydroxyl group, cyano group, phenyl group, or amino group. The valence of the aforementioned aliphatic groups is preferably 1 to 2.

[0030] When Y1' is a divalent organic group (Ah), it is preferable that Y1' is a diamine with two amino groups removed from it (hereinafter also referred to as a specific diamine (Ah)). Specific examples of the aforementioned specific diamine (Ah) are preferably aromatic diamines represented by "A1'-(L-Ah)m'" or "(A11')2-Ah'". Here, A1' indicates that there are two primary amino groups bonded to the m' valence group of the aromatic group. A11' indicates that there is one primary amino group bonded to the monovalent group of the aromatic group. Specific examples of aromatic ring structures in aromatic groups are benzene rings, naphthyl rings, biphenyl structures, or aromatic ring structures consisting of two benzene rings linked by a linking group (-CH 2-, -C(CH 3) 2-, -O-, -CO-, -CO-O-, -NR- (R represents a hydrogen atom or a methyl group), or -NR-CO- (R represents a hydrogen atom or a methyl group), or -N=N-, etc.). L represents a single bond, -O-, -CO-, -CO-O-, -NR- (R represents a hydrogen atom or a methyl group), or -NR-CO- (R represents a hydrogen atom or a methyl group). Ah represents a monovalent aliphatic carboxyl group. m' is an integer from 1 to 2. Ah' represents a divalent aliphatic carboxyl group.

[0031] More ideal examples of the aforementioned specific diamines (Ah) can be listed from the group of diamines represented by the following formulas (Ah-1) to (Ah-5). [Chemistry 9] In formulas (Ah-1) to (Ah-3), L represents a single bond, -O-, -CO-, -CO-O-, -NR- (R represents a hydrogen atom or a methyl group), or -NR-CO- (R represents a hydrogen atom or a methyl group). Ak is an alkyl group with 1 to 20 carbon atoms, and one of the hydrogen atoms in the alkyl group may be replaced by a hydroxyl group, a halogen atom, or a phenyl group. In formula (Ah-3), n3 is an integer of 0 or 1. In formula (Ah-4), m4 independently represents an integer of 1 to 5. In formula (Ah-5), A5 represents a straight-chain or branched alkyl group with 1 to 5 carbon atoms, and m5 is an integer of 1 to 5.

[0032] (Divalent organic group (ph)) A divalent organic group (ph) possesses a phenolic hydroxyl group. A phenolic hydroxyl group refers to a hydroxyl group bonded to an aromatic hydrocarbon ring. Aromatic hydrocarbon rings include, for example, benzene rings and naphthalene rings. The divalent organic group (ph) preferably has a structure represented by the formula (ph-1) as the aforementioned phenolic hydroxyl group. [Chemistry 10] Ar represents a benzene ring or a naphthalene ring. R represents a hydrogen atom, a methyl group, a methoxy group, or a halogen atom. * represents an atomic bond. When Ar is a benzene ring, p represents an integer from 1 to 5, q represents an integer from 0 to 4, and r represents an integer from 1 to 5. The sum of p, q, and r is 6. When Ar is a naphthalene ring, p represents an integer from 1 to 7, q represents an integer from 0 to 6, and r represents an integer from 1 to 7. The sum of p, q, and r is 8.

[0033] When Y1' is a divalent organic group (ph), it is preferable that Y1' is a group from which two amino groups have been removed from a diamine having the structure represented by the above formula (ph) (hereinafter also referred to as a specific diamine (ph)). A more ideal specific example of the above specific diamine (ph) can be listed as a diamine represented by the following formula (ph-0). [Chemistry 11] P represents the structure shown in equation (ph-1) above (except that r in equation (ph-1) represents 1). L represents a single bond or a divalent group.

[0034] In the above formula (ph-0), the divalent group of L can be a divalent hydrocarbon group with 1 to 30 carbon atoms, or a group in which at least one methylene group is replaced by a divalent functional group such as -O-, -S-, -CO-, -COO-, -COS-, -NR-, -CONR-, -CO-NR-CO- (where R is a hydrogen atom or an alkyl group with 1 to 3 carbon atoms). Furthermore, the hydrogen atom in the hydrocarbon group can also be replaced by, for example, a halogen atom, a hydroxyl group, a cyano group, or an amino group. Hydrocarbon groups can be listed as chain hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. Specific examples of chain hydrocarbon groups include divalent straight-chain hydrocarbon groups with 1 to 30 carbon atoms that do not have a cyclic structure, or branched hydrocarbon groups, preferably alkyl groups with 1 to 30 carbon atoms. Specific examples of alicyclic hydrocarbon groups include the structures shown for alicyclic hydrocarbon groups in W3. Specific examples of aromatic hydrocarbon groups include the structures shown for aromatic hydrocarbon groups in W1 to W4 above. In the above formula (ph-0), the divalent base of L, considering the ideal effect of the present invention, is preferably -(CH2)nO- (n is an integer from 1 to 6), -(CH2)nC(=O)-NH- (n is an integer from 1 to 6), -(CH2)nOC(=O)- (n is an integer from 1 to 6), -(CH2)nC(=O)-O- (n is an integer from 1 to 6), -O-(CH2)nO- (n is an integer from 1 to 6), -C(=O)-O-(CH2)nO- (n is an integer from 1 to 6), -(CH2)mC(=O)-O-(CH2)n- (m and n are each an integer from 1 to 6), or -C(=O)-O-(CH2)nOC(=O)- (n is an integer from 1 to 6).

[0035] In the above formula (ph-0), P is preferably represented by the structure of the following formulas (p-1) to (p-6). [Chemistry 12]

[0036] Specific examples of the aforementioned diamines (ph) can be cited, for example, as shown in the following structural formulas (1-18). [Chemistry 13] [Chemistry 14]

[0037] Another embodiment of the present invention is a liquid crystal alignment agent in which the polymer component meets at least one of the following conditions (i-1), (ii-1), and (ii-2). Condition (i-1): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1), a repeating unit (a1') represented by formula (1'), and a repeating unit (a2) represented by formula (2), and a polyimide consisting of a polyimide of the polyimide precursor. Condition (ii-1): The above polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) above and a repeating unit (a2) represented by formula (2) below, and a polyimide consisting of a polyimide of the polyimide precursor, and at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by formula (1') above and a polyimide consisting of a polyimide of the polyimide precursor. Condition (ii-2): The above polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) above and a polyimide consisting of a polyimide of a polyimide precursor with a amide. and at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by formula (1') above and a repeating unit (a2) represented by formula (2) below and a polyimide consisting of a polyimide of a polyimide precursor with a amide. Furthermore, in condition (i-1), the repeating unit (a1) represented by equation (1), the repeating unit (a1') represented by equation (1'), and the repeating unit (a2) represented by equation (2) exist within the same molecule of the polymer.

[0038] (Repeating unit (a2)) The polymer component contained in the liquid crystal alignment agent of the present invention may further have a repeating unit (a2) represented by the following formula (2). The polymer component may also be a polyimide of a polyimide precursor having a repeating unit (a2) represented by the following formula (2). Furthermore, the repeating unit (a2) may be one type or two or more types. [Chemistry 15]

[0039] X2 represents a tetravalent organogroup. Y2 represents a divalent organogroup with the radical -XJ. R and Z each independently represent a hydrogen atom or a monovalent organogroup. In the above-mentioned base -XJ, X represents a single bond, -(CH2)a- (a is an integer from 1 to 15), -CONH-, -NHCO-, -CO-N(CH3)-, -NH-, -O-, -COO-, -OCO-, -Ak-O-CO-CH=CH-** (** represents an atomic bond with an aromatic hydrocarbon group. Ak represents a divalent organic group with 1 to 10 carbon atoms.), or -(A1)a0-((CH2)a1-A1)m1- (a0 is an integer of 0 or 1, a1 is an integer from 1 to 15, A1 independently represents -O- or -COO-, m1 is an integer from 1 to 2. When m1 is 2, multiple a1s independently have the above definitions.). J represents a monovalent organic group having at least one group selected from the group consisting of alicyclic hydrocarbon groups with 4 to 40 carbon atoms and aromatic hydrocarbon groups with 6 to 40 carbon atoms. However, at least one hydrogen atom in the aforementioned alicyclic hydrocarbon group and aromatic hydrocarbon group is substituted by a halogen atom, an alkyl group containing a halogen atom with 1 to 10 carbon atoms, an alkoxy group containing a halogen atom with 1 to 10 carbon atoms, an alkyl group with 3 to 10 carbon atoms, an alkoxy group with 3 to 10 carbon atoms, or an alkenyl substituent (v) with 3 to 10 carbon atoms. Furthermore, any carbon-carbon single bond in these substituents (v) (except for the halogen atom) may be interrupted by -O-. In addition to having the aforementioned alicyclic hydrocarbon group and aromatic hydrocarbon group, J may also have at least one group selected from the group consisting of alicyclic hydrocarbon groups and aromatic hydrocarbon groups substituted with unsubstituted or substituents other than the aforementioned substituents (v).

[0040] Of the Y 2 mentioned above, it is preferable to have two amino groups removed from the aromatic diamine represented by "AXJ" (hereinafter also referred to as a specific diamine (V)). In the aforementioned specific diamine (V), A indicates that there are two primary amino groups bonded to a monovalent aromatic group. Specific examples of aromatic ring structures in aromatic groups include benzene rings, naphthyl rings, and biphenyl structures.

[0041] The alicyclic hydrocarbon group with 4 to 40 carbon atoms in J can be exemplified by cyclobutyl, cyclopentyl, cyclohexyl, cyclodecyl, and groups with a steroid skeleton (e.g., cholesteryl, cholesterol, lanosteryl, etc.). The aromatic hydrocarbon group with 6 to 40 carbon atoms can be exemplified by phenyl, naphthyl, etc. When J contains at least one of cyclohexyl and phenyl, the group "-XJ" can be exemplified by the following structures (S1), and more ideal structures can be exemplified by the following formulas (S1-1) to (S1-5). [Chemistry 16] X1 represents the definition of X in the radical -XJ, or -O-CO-CH=CH-** (** represents an atomic bond with the phenyl group). G1 represents a divalent cyclic group selected from phenyl and cyclohexyl groups. Any hydrogen atom on the aforementioned cyclic group may also be replaced by an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorinated alkyl group having 1 to 3 carbon atoms, a fluorinated alkoxy group having 1 to 3 carbon atoms, or a fluorine atom. m is an integer from 1 to 4. When m is 2 or more, multiple X1 and G1 can each independently have the above definition. R 1 represents a fluorine atom, an alkyl group containing fluorine atoms with 1 to 10 carbon atoms, an alkoxy group containing fluorine atoms with 1 to 10 carbon atoms, an alkyl group with 3 to 10 carbon atoms, an alkoxy group with 3 to 10 carbon atoms, or an alkoxyalkyl group with 3 to 10 carbon atoms. [Chemistry 17] X1, R1 are synonyms with X1, R1 in the above equation (S1).

[0042] Specific examples of the aforementioned diamine (V) can be listed as diamines represented by formulas (d-1) to (d-2). More ideal examples can be listed as diamines represented by formulas (d-1) to (d-2) where the radical "-XJ" is the above structure (S1) or any of the above formulas (S1-1) to (S1-5), and diamines having a steroid skeleton such as cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryl 3,5-diaminobenzoate, cholesteryl 3,5-diaminobenzoate, lanosteryl 3,5-diaminobenzoate, and 3,6-bis(4-aminobenzoyloxy)cholestane. In the following formulas (d-1) to (d-2), X represents -Ak-O-CO-CH=CH-** (** represents an atomic bond with an aromatic hydrocarbon group. Ak represents a divalent organic group with 1 to 10 carbon atoms.). Ideal specific examples include [4-[(E)-3-[2-(2,4-diaminophenyl)ethoxy]-3-sideoxy-prop-1-enyl]phenyl]4-(4,4,4-trifluorobutoxy)benzoate and [4-[(E)-3-[[5-amino-2-[4-amino-2-[[(E)-3-[4-[4-(4,4,4-trifluorobutoxy)benzoyl]oxyphenyl]prop-2-enyl]oxymethyl]phenyl]phenyl]methoxy]-3-sideoxy-prop-1-enyl]phenyl]4-(4,4,4-trifluorobutoxy)benzoate. [Chemistry 18] X, J, and the X and J of the above basis -XJ are synonymous, including ideal states. In the aforementioned equation (d-2), the two X and J can be the same or different.

[0043] (Repeating unit (a3)) The polymer component contained in the liquid crystal alignment agent of the present invention may further have a repeating unit (a3) ​​represented by the following formula (3). The polymer component contained in the liquid crystal alignment agent of the present invention may also contain a polyimide that is a polyimide precursor having a repeating unit (a3) ​​represented by the following formula (3). Furthermore, the repeating unit (a3) ​​may be one type or two or more types. [Chemistry 19] X3 represents a tetravalent organogroup. Y3 represents a divalent organogroup, and specifically a divalent organogroup other than those defined by Y1, Y1', and Y2 in the above formula. The two R and Z are synonymous with R and Z in formula (1).

[0044] Y3 is preferably a divalent organic group from which two amino groups have been removed from the diamines described below (hereinafter also referred to as other diamines). Furthermore, other diamines are not particularly limited, and diamines other than those described below may also be used.

[0045] p-Phenylenediamine, 2,3,5,6-Tetramethyl-p-phenylenediamine, 2,5-Dimethyl-p-phenylenediamine, m-Phenylenediamine, 2,4-Dimethyl-m-phenylenediamine, 2,5-Diaminotoluene, 2,6-Diaminotoluene, 2,2'-Dimethyl-4,4'-Diaminobiphenyl, 3,3'-Dimethyl-4,4'-Diaminobiphenyl, 3,3'-Dimethoxy-4,4'-Diaminobiphenyl, 3,3'-Dihydroxy-4,4'-Diaminobiphenyl, 2,2'-Difluoro-4,4'-Diaminobiphenyl, 3,3'-Difluoro-4,4'-Diaminobiphenyl, 2,2'-Bis(trifluoromethyl)-4,4'-Diaminobiphenyl, 3,3'-Bis(trifluoromethyl)-4,4'-Diaminobiphenyl Aminobiphenyl, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 2,5-diaminonaphthalene, 2,6-diaminonaphthalene, 2,7-diaminonaphthalene, bis(4-aminophenoxy)methane, 1,2-bis(4-aminophenyl)ethane, 1,2-bis(4-aminophenoxy)ethane, 1,3-bis(3-aminophenyl)propane, 1,4-bis(4-aminophenyl)butane, 1,4-bis(4-amino-2-methylphenoxy)butane, 1,4-bis(3-aminophenyl)butane, bis(3,5-diaminophenyl)butane, (diethyl-4-aminophenyl)methane, 1,5-bis(4-aminophenoxy)pentane, 1,5-bis(3-aminophenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,6-bis(3-aminophenoxy)hexane, 1,7-bis(4-aminophenoxy)heptane, 1,7-bis(3-aminophenoxy)heptane, 1,8-bis(4-aminophenoxy)octane, 1,8-bis(3-aminophenoxy)octane, 1,9-bis(4-aminophenoxy)nonane, 1,9-bis(3-aminophenoxy)nonane, 1,10-bis(4-aminophenoxy)decane, 1,10-bis(3-aminophenoxy)decane, 1,11-bis(4-aminophenoxy)decane 1,11-bis(3-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)dodecane, 1,12-bis(3-aminophenoxy)dodecane, 3-[2-[2-[2-(4-aminophenoxy)ethoxy]ethoxy]aniline, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)diphenyl ether, 1,4-bis[4-(4-aminophenoxy)phenoxy]benzene, 1,2-bis(6-amino-2-naphthoxy)ethane, 1,2-Bis(6-amino-2-naphthyl)ethane, 6-[2-(4-aminophenoxy)ethoxy]-2-naphthylamine, 4'-[2-(4-aminophenoxy)ethoxy]-[1,1'-biphenyl]-4-amine, 1,4-bis[2-(4-aminophenyl)ethyl]succinate, 1,6-bis[2-(4-aminophenyl)ethyl]adipate, 1,4-epoxyphenylbis(4-aminobenzoate), 1,4-epoxyphenylbis(3-aminobenzoate), 1,3-epoxyphenylbis(4-aminobenzoate), 1,3-epoxyphenylbis(3-aminobenzoate), bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl) isophthalate; diamines with photoaligning groups such as 4,4'-diaminoazobenzene, diaminodiphenylacetylene, or 4,4'-diaminochalcone; diamines with photopolymerizable groups at the end such as 2-(2,4-diaminophenoxy)ethyl methacrylate and 2,4-diamino-N,N-diallyl aniline; benzoin or its alkyl ether derivatives represented by 1-(4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylpropanone, 2-(4-(2-hydroxy-2-methylpropionic acid)phenoxy)ethyl-3,5-diaminobenzoate, benzyl ketals, acetophenones, phosphine oxides, diphenyl ketones, or amino groups. Diamines such as diphenyl ketones, which possess an intramolecular group that functions as a free radical polymerization initiator (hereinafter also referred to as diamines with free radical initiation function); diamines with amide bonds such as 4,4'-diaminophenylaniline; diamines with urea bonds such as 1,3-bis(4-aminophenyl)urea, 1,3-bis(4-aminobenzyl)urea, and 1,3-bis(4-aminophenylethyl)urea; 4,4'-sulfadiphenylamine, 3,3'-sulfadiphenylamine, bis(4-aminophenyl)silane, bis(3-aminophenyl)silane, dimethyl-bis(4-aminophenyl)silane, dimethyl-bis(3-aminophenyl)silane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenylamine, etc. Benzene ether, 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis(3-aminophenyl)hexafluoropropane, 2,2-bis(3-amino-4-methylphenyl)hexafluoropropane, 2,2-bis(4-aminophenyl)propane, 2,2-bis(3-aminophenyl)propane, 2,2-bis(3-amino-4-methylphenyl)propane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ketone, 1,4-bis(4-aminophenyl)benzene, 1,3-Bis(4-aminophenyl)benzene, 1,4-bis(4-aminobenzyl)benzene; 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl)piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diamine N-phenyl-3,6-diaminocarbazole, N-(3-(1H-imidazol-1-yl)propyl-3,5-diaminobenzamide, 1,4-bis(p-aminobenzyl)piperidine, 4,4'-[propane-1,3-diylbis(piperidine-1,4-diyl)]diphenylamine, 4-(4-aminophenoxycarbonyl)-1-(4-aminophenyl)piperidine Diamines represented by formulas (z-1) to (z-5) (where m in formula (z-2) has each independently the following definition), 2,5-bis(4-aminophenyl)pyrrole, 4,4'-(1-methyl-1H-pyrrole-2,5-diyl)bis[aniline], 1,4-bis-(4-aminophenyl)-piperazine, 2-N-(4-aminophenyl)pyridine-2,5-diamine, 2-N-(5-aminopyridin-2-yl)pyridine-2,5-diamine, 2-(4-aminophenyl)-5-aminobenzimidazole, 2-(4-aminophenyl)-6-aminobenzimidazole, 5-(1H-benzimidazol-2-yl)phenyl-1,3-diamine, etc., containing heterocyclic diamines, or 4,4'-diaminodiphenylamine, 4,4'- Diamines with a diphenylamine structure, such as diaminodiphenyl-N-methylamine, N,N'-bis(4-aminophenyl)-1,4-phenylenediamine, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, or N,N'-bis(4-aminophenyl)-N,N'-dimethyl-1,4-phenylenediamine, are representative of diamines having at least one nitrogen-containing structure selected from the group consisting of nitrogen-containing heterocycles, secondary amine groups, and tertiary amine groups (hereinafter also referred to as specific nitrogen-containing structures). (However, the molecule does not contain an amine group that has been bonded to a protecting group that has been removed and replaced by a hydrogen atom upon heating. Specific diamines (s-Ox) and specific diamines (m-Ox) are excluded.) 3,5-Diphenyl Aminobenzyl alcohol, 2,4-diaminobenzyl alcohol; 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 1,2-bis(4-aminophenyl)ethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenyl ether-3,Aromatic diamines with aromatic carboxyl groups, such as 3'-dicarboxylic acid; 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 1-(4-aminophenyl)-1,3,3-trimethyl-1H-dihydroindene-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-indene-6-amine; N,N'-bis(2-tert-butoxycarbonylamino-4-aminophenyl)hexamethylenediamine, 4-amino-N-(2-tert-butoxycarbonylamino-4-aminophenyl)benzamide, N-[(2,5-diaminophenyl)methyl]-1,1-dimethylethyl ester of carbamate, N-[3-(2,5-diaminophenyl)propyl]-1, 1-Dimethyl ethyl ester, N,N-[(2,5-diamino-1,3-epoxyphenyl)di-3,1-propanediyl]bis-C,C-bis(1,1-dimethyl ethyl) ester, N-tert-butoxycarbonyl-N-(2-(4-aminophenyl)ethyl)-N-(4-aminobenzyl)amine, 4-amino-2-tert-butoxycarbonylamino-1,1'-[(1,1,3,3-tetramethyl-1,3-disiloxanediyl)di-4,1-butanediyl] ester, N-[2-(4-aminophenyl)ethyl]-N-[[[2-(4-aminophenyl)ethyl]amino]carbonyl]-1,1-dimethyl ethyl ester, N-(4-aminophenyl)-N -[[1-(4-aminophenyl)-4-piperidinyl]methyl]-1,1-dimethyl ethyl ester and other diamines having the group "-N(D)-" (D represents a protecting group that is removed and replaced by a hydrogen atom upon heating, preferably a tert-butoxycarbonyl). 1-Dodecyloxy-2,4-diaminobenzene, 1-tetradecyloxy-2,4-diaminobenzene, 1-pentadecanyloxy-2,4-diaminobenzene, 1-hexadecyloxy-2,4-diaminobenzene, 1-octadecyloxy-2,4-diaminobenzene, 1-dodecyloxy-2,5-diaminobenzene, 1-tetradecyloxy-2,5-diaminobenzene, 1-pentadecanyloxy-2,5-diaminobenzene, 1-hexadecyloxy-2,5-diaminobenzene, Aromatic diamines having long-chain alkyl groups with 12 to 20 carbons, represented by 1-octadecyloxy-2,5-diaminobenzene; diamines having siloxane bonds, such as 1,3-bis(3-aminopropyl)tetramethyldisiloxane and 1,3-bis[3-(p-aminophenylaminomethyl)propyl]tetramethyldisiloxane; diamines with two amino groups bonded to a alkyl group, such as m-xylene diamine, 1,3-propane diamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), and any of the formulas (Y-1) to (Y-167) disclosed in International Publication No. 2018 / 117239. [Chemistry 20]

[0046] The diamines with photopolymerizable groups at the ends and the diamines with free radical initiation functions mentioned above can be used, taking into account the viewpoint of accelerating the response speed of liquid crystal display elements using PSA and SC-PVA modes, in the manufacture of the above polymer components, one or more of them can be used.

[0047] Among the other diamines mentioned above, from the viewpoint of ideally obtaining the effects of the present invention, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ketone, 2,2'-dimethyl-4,4'-diaminobiphenyl, the above-mentioned diamines having free radical initiation function, the above-mentioned diamines having a specific nitrogen-containing structure, and the above-mentioned diamines having the group "-N(D)-" are preferred.

[0048] Furthermore, specific forms of polymer components having the aforementioned repeating unit (a2) and / or repeating unit (a3) ​​can be listed as copolymers and polymer blends. Examples of the copolymers described above include at least one polymer selected from the group consisting of polyimide precursors and their amide polymers having the repeating units (a1), (a1'), (a2), and / or (a3) ​​within the same molecule. The aforementioned polymer blend is, for example, a mixture of at least one polymer (P-a1+an) selected from the group consisting of polyimide precursors and their amide polymers having repeating units (a1), (a2), and / or (a3) ​​within the same molecule, and at least one polymer (P-a1'+an) selected from the group consisting of polyimide precursors and their amide polymers having repeating units (a1'), (a2), and / or (a3) ​​within the same molecule. The aforementioned copolymer or polymer blend can be used alone or in combination.

[0049] When the copolymer contains at least one of the repeating unit (a2) and the amide-imide structural unit of the repeating unit (a2), the total proportion of the repeating unit (a2) and the amide-imide structural unit of the repeating unit (a2) is preferably 5 to 95 mol%, more preferably 10 to 90 mol%, and more preferably 10 to 85 mol% of the total repeating unit constituting the copolymer, from the viewpoint of ideally obtaining the effects of the present invention. In this case, the total content of the aforementioned repeating unit (a1), the aforementioned repeating unit (a1') and their amide-modified structural units, from the viewpoint of ideally obtaining the effects of the present invention, is preferably 95 mol% or less, and more preferably 90 mol% or less.

[0050] In the above-mentioned polymer blend, when the polymer (P-a1+an) contains at least one of the repeating unit (a2) and the amide-imide structural unit of the repeating unit (a2), the total proportion of the repeating unit (a2) and the amide-imide structural unit of the repeating unit (a2) is preferably 5 to 95 mol%, more preferably 10 to 90 mol%, and more preferably 10 to 85 mol% of the total repeating unit constituting the polymer (P-a1+an) in order to ideally obtain the effects of the present invention. In this case, the total content of the repeating unit (a1) and the amide-imide structural unit of the repeating unit (a1) is preferably 95 mol% or less, and more preferably 90 mol% or less, from the viewpoint of ideally obtaining the effect of the present invention.

[0051] Furthermore, in the aforementioned polymer blend, when the polymer (P-a1'+an) contains at least one of the repeating unit (a3) ​​and the amide-imide structural unit of the repeating unit (a3), the total proportion of the repeating unit (a3) ​​and the amide-imide structural unit of the repeating unit (a3) ​​is, from the viewpoint of ideally obtaining the effects of the present invention, 10 to 95 mol% of all repeating units constituting the polymer (P-a1'+an) is more ideal, and 20 to 90 mol% is even more ideal. In this case, the total content of the repeating unit (a1') and the amide-imide structural unit of the repeating unit (a1') is preferably 95 mol% or less, and more preferably 90 mol% or less, from the viewpoint of ideally obtaining the effect of the present invention.

[0052] When the polymer component is the above-mentioned polymer blend, the mass ratio of the content of the above-mentioned polymer (P-a1'+an) to the content of the above-mentioned polymer (P-a1+an) ((P-a1+an) / (P-a1'+an)) is preferably 5 / 95 to 95 / 5, and more preferably 10 / 90 to 90 / 10.

[0053] In formulas (1), (1'), and (2) to (3) above, X1, X1', and X2 to X3 each independently represent a tetravalent organic group. X1, X1', and X2 to X3 are preferably tetravalent organic groups derived from tetracarboxylic dianhydrides or their derivatives (tetracarboxylic dihalides, tetracarboxylic diesters, or tetracarboxylic diester dihalides, etc.). Examples of tetravalent organic groups include acyclic aliphatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, aromatic tetracarboxylic dianhydrides, or their derivatives. It is more preferable that the tetracarboxylic dianhydride or its derivatives contain at least one substructure selected from the group consisting of benzene rings, cyclobutane rings, cyclopentane rings, and cyclohexane rings. To obtain the tetracarboxylic dianhydride or its derivatives that constitute the polyimide precursor in the polymer composition, it is preferable to use a tetravalent organic group derived from acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, or its derivatives. More preferably, it is a tetracarboxylic dianhydride or its derivatives containing at least one substructure selected from the group consisting of cyclobutane ring structure, cyclopentane ring structure, and cyclohexane ring structure. Furthermore, acyclic aliphatic tetracarboxylic dianhydrides are acidic dianhydrides obtained by intramolecularly dehydrating the four carboxyl groups bonded to the chain hydrocarbon structure. However, they do not necessarily have to be composed solely of chain hydrocarbon structures; some of them may also have alicyclic structures, aromatic ring structures, or heteroatoms such as oxygen atoms. Alicyclic tetracarboxylic dianhydrides are acidic dianhydrides obtained by intramolecular dehydration of four carboxyl groups, including at least one carboxyl group bonded by an alicyclic structure. However, none of these four carboxyl groups are bonded to an aromatic ring. Furthermore, it is not necessary for the structure to be solely alicyclic; a portion of it may also possess a chain hydrocarbon structure or an aromatic ring structure. Aromatic tetracarboxylic acid dianhydrides are acidic dianhydrides obtained by intramolecularly dehydrating four carboxyl groups, including at least one carboxyl group linked by an aromatic ring. However, they do not necessarily have to be composed solely of an aromatic ring structure; some may also have chain hydrocarbon structures or alicyclic structures.

[0054] It is preferable that X1, X1', and X2~X3 are tetravalent organic groups derived from the following tetracarboxylic dianhydrides or their derivatives (hereinafter collectively referred to as specific tetracarboxylic acid derivatives).

[0055] Acyclic aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride; 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dichloro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-difluoro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-bis(trifluoromethyl)-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4- Cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3',4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 4-(2,5-di-side-oxytetrahydrofuran-3-yl)tetrahydronaphthyl-1,2-dicarboxylic dianhydride, 5-(2,5-di-side-oxytetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 5-(2,5-di-side-oxytetrahydrofuran-3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, bicyclo[2 [2.2.2] Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, bicyclic [2.2.2]octane-2,3,5,6-tetracarboxylic dianhydride, 2,4,6,8-tetracarboxylic bicyclic [3.3.0]octane-2:4,6:8-dianhydride and other alicyclic tetracarboxylic dianhydrides; benzopyrene dianhydride, 3,3',4,4'-diphenyl ketone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3',4,4'-diphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-perfluoroisopropylidene diphthalene Aromatic tetracarboxylic acid dianhydrides such as formic acid dianhydride, 3,3',4,4'-biphenyltetracarboxylic acid dianhydride, 2,2',3,3'-biphenyltetracarboxylic acid dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, ethylene glycol bis(triphenyl)carboxylic acid anhydride, 4,4'-(hexafluoroisopropylidene)diphthalic acid anhydride, 4,4'-carbonyldiphthalic acid anhydride, 4,4'-oxobis(1,4-epoxyphenyl)bis(phthalic acid) dianhydride, or 4,4'-methylenebis(1,4-epoxyphenyl)bis(phthalic acid) dianhydride; others, such as the tetracarboxylic acid dianhydrides described in Japanese Patent Application Publication No. 2010-97188.

[0056] Ideal examples of the aforementioned specific tetracarboxylic acid derivatives are 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3- Difluoro-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-bis(trifluoromethyl)-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 3,3',4,4'-dicyclohexyltetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 5-(2,5-disideloxytetrahydrofuran) 5-(2,5-di-side-oxytetrahydrofuran-3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 2,4,6,8-tetracarboxylic acid bicyclo[3.3.0]octane-2:4,6:8-dianhydride, benzopyrene dicarboxylic acid ... Anhydride, 3,3',4,4'-diphenyl ketone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 2,2',3,3'-biphenyl tetracarboxylic dianhydride, or derivatives thereof.

[0057] The ideal proportion of the aforementioned specific tetracarboxylic acid derivatives is 10 mol% or more, more preferably 20 mol% or more, and even more preferably 50 mol% or more, relative to 1 mol of all tetracarboxylic acid components used to obtain the polyimide precursor contained in the polymer component.

[0058] In formulas (1), (1'), and (2) to (3), the monovalent organic groups R and Z are each independently a monovalent hydrocarbon group with 1 to 20 carbon atoms, a monovalent group A formed by replacing the methylene group of the hydrocarbon group with -O-, -S-, -CO-, -COO-, -COS-, -NR 3-, -CO-NR 3-, -Si(R 3) 2- (where R 3 is a hydrogen atom or a monovalent hydrocarbon group with 1 to 10 carbon atoms), -SO 2-, etc., a monovalent hydrocarbon group or at least one hydrogen atom bonded to the carbon atom of the monovalent group A is replaced by a halogen atom, hydroxyl, alkoxy, nitro, amino, mercapto, nitroso, alkylsilyl, alkoxysilyl, silyl alcohol, sulfinic acid, phosphin, carboxyl, cyano, sulfonyl, acetyl, etc., a monovalent group having a heterocyclic ring. Among them, alkyl groups with 1 to 10 carbon atoms, alkenyl groups with 2 to 10 carbon atoms, alkynyl groups with 2 to 10 carbon atoms, terbutoxycarbonyl groups, or 9-furomethoxycarbonyl groups are more ideal, alkyl groups with 1 to 3 carbon atoms are better, and methyl groups are even more ideal. From the perspective of achieving the effects of the present invention, it is more ideal for R and Z to be hydrogen atoms or alkyl groups having 1 to 3 carbon atoms, and even more ideal for hydrogen atoms or methyl groups.

[0059] <Polyimide precursors and manufacturing methods of polyimide> Examples of polyimide precursors used in this invention include polyamides and polyamide esters. The polyimide precursors used in this invention can be synthesized, for example, by a known method as described in International Publication No. 2013 / 157586. Specifically, it can be synthesized by reacting a diamine component and a tetracarboxylic acid derivative component in a solvent (condensation polymerization). Examples of the tetracarboxylic acid derivative component include tetracarboxylic dianhydride or its derivatives. When a portion of the polymer contains an acetic acid structure, for example, a polymer with an acetic acid structure (polyacrylic acid) can be obtained by reacting the tetracarboxylic dianhydride component with the diamine component. There are no particular restrictions on the solvent, as long as the resulting polymer can dissolve it. For example, when a polymer with repeating units represented by formula (1) above where R is a hydrogen atom is obtained, the diamine component can be a diamine with the structure -N(Z)-Y1-N(Z)- (Y1 and Z are defined as in formula (1) above), and the tetracarboxylic acid derivative component can be a tetracarboxylic acid derivative with the structure of the following formula. [Chemistry 21] The definition of X1 is the same as in equation (1) above.

[0060] Polyamides containing a portion of a polymer with a polyamide structure can be obtained by known methods such as: [I] reacting the polyamide obtained by the above methods with an esterifying agent; [II] reacting a tetracarboxylic acid diester with a diamine; [III] reacting a tetracarboxylic acid diester dihalide with a diamine.

[0061] Furthermore, polyimide can be obtained by cyclizing (nimidizing) the aforementioned polyimide precursor. Also, the nimidization rate referred to in this specification is the ratio of nimidyl groups to the total amount of nimidyl groups and carboxyl groups (or their derivatives) derived from tetracarboxylic dianhydride or its derivatives. The nimidization rate in polyimide is not necessarily 100% and can be adjusted arbitrarily according to the application and purpose. The amide content of the polyamide contained in the liquid crystal alignment agent of the present invention, considering the guarantee of solubility, is preferably 10-95%, more preferably 20-95%, and even more preferably 30-90%.

[0062] Methods for amide-imidizing polyimide precursors include thermal amide-imidization by directly heating a solution of the polyimide precursor or catalytic amide-imidization by adding a catalyst (such as an alkaline catalyst like pyridine or an acid anhydride like acetic anhydride) to a solution of the polyimide precursor.

[0063] <End-capping agent> When synthesizing the polymer of this invention, a tetracarboxylic acid component containing tetracarboxylic dianhydride or its derivatives, and a diamine component containing the aforementioned diamine, along with a suitable end-sealing agent, can be used to synthesize an end-sealing polymer. The end-sealing polymer has the effect of increasing the film hardness of the alignment film obtained from the coating and improving the adhesion properties between the sealant and the alignment film. The polyimide precursor and the ends of the polyimide in this invention are derived, for example, from amino, carboxyl, anhydride, or end-capping agents described below. Amine, carboxyl, and anhydride groups can be obtained through conventional condensation reactions or by sealing the ends using the end-capping agents described below.

[0064] End-capping agents, such as acetic anhydride, maleic anhydride, naphthalic anhydride, phthalic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, 3-(3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, 4-ethynylphthalic anhydride, etc.; dibutyl dicarbonate, diallyl dicarbonate, etc.; acrylonitrile chloride, methacrylic chloride, etc. Nicotinic acid, chlorocarbonyl compounds, etc.; monoamine compounds such as aniline, 2-aminophenol, 3-aminophenol, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, etc.; isocyanates with unsaturated bonds such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate.

[0065] The preferred ratio of the capping agent to the total 100 moles of diamine used is 0.01 to 20 moles, and even better is 0.01 to 10 moles.

[0066] When considering the strength, workability and coating properties of the liquid crystal alignment film obtained from it, the molecular weight of the polymer used in this invention is preferably 5,000 to 1,000,000, and more preferably 10,000 to 150,000, as determined by the GPC (Gel Permeation Chromatography) method.

[0067] (Liquid crystal alignment agent) The liquid crystal alignment agent of the present invention is a liquid composition formed by dispersing or dissolving polymers and other components as needed in a suitable organic solvent.

[0068] Furthermore, other polymers besides those mentioned above may also be mixed into the liquid crystal alignment agent used in the manufacture of the liquid crystal alignment film. Specific examples of other polymers include polymers selected from the group consisting of polysiloxanes, polyesters, polyamides, polyureas, polyorganosiloxanes, cellulose derivatives, polyacetals, polystyrene derivatives, poly(styrene-maleic anhydride) copolymers, poly(isobutylene-maleic anhydride) copolymers, poly(vinyl ether-maleic anhydride) copolymers, poly(styrene-phenylmaleimide) derivatives, and poly(meth)acrylates. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, SMA3000 (manufactured by Cray Valley), and GSM301 (manufactured by GIFUSHELLAC). Specific examples of poly(isobutylene-maleic anhydride) copolymers include ISOBAM-600 (manufactured by Kuraray). Specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by ASHLAND). Other polymers may be used alone or in combination of two or more. The content of other polymers should ideally be less than 50 parts by mass relative to the total number of polymers in the liquid crystal alignment agent (100 parts by mass), 1 to 50 parts by mass is better, and 5 to 40 parts by mass is even better.

[0069] The liquid crystal alignment agent of the present invention may also contain components other than those mentioned above, as needed. These components may include, for example, at least one crosslinking compound selected from the group consisting of a crosslinking compound (c-1) having at least one substituent selected from epoxy, oxacyclobutane, oxazoline, cyclic carbonate, terminal isocyanate, hydroxyl, and alkoxy groups, and a crosslinking compound (c-2) having a polymerizable unsaturated group; functional silane compounds; metal chelate compounds; curing accelerators; surfactants; antioxidants; sensitizers; preservatives; and compounds used to adjust the dielectric constant and resistance of the liquid crystal alignment film.

[0070] Ideal examples of the aforementioned crosslinking compounds (c-1) and (c-2) can be listed below. Compounds containing epoxy groups include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromonepentyl glycol diglycidyl ether, 1,3,5,6-tetracyclooxypropyl-2,4-hexanediol, bisphenol A type epoxy resins such as EPIKOTE 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins such as EPIKOTE 807 (manufactured by Mitsubishi Chemical Corporation), hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Corporation), and YX6... Epoxy resins containing a biphenyl backbone, such as 954BH30 (manufactured by Mitsubishi Chemical Corporation); phenol-formaldehyde varnish-type epoxy resins, such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.); cresol-formaldehyde varnish-type epoxy resins (ortho, meta, para) such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.); tetra(epoxypropoxymethyl)methane; N,N,N',N'-tetracyclooxypropyl-1,4-phenylenediamine; N,N,N',N'-tetracyclooxypropyl-2,2'-dimethyl-4,4'-diaminobiphenyl; 2,2-bis[4-(N,N-dicyclooxypropyl-4-aminophenoxy)phenyl]propane; N,N,N',N'-tetracyclooxypropyl Compounds containing tertiary nitrogen atoms and aromatic carbon atoms, such as -4,4'-diaminodiphenylmethane; N,N,N',N'-tetracyclooxypropyl-1,2-diaminocyclohexane, N,N,N',N'-tetracyclooxypropyl-1,3-diaminocyclohexane, N,N,N',N'-tetracyclooxypropyl-1,4-diaminocyclohexane, bis(N,N-dicyclooxypropyl-4-aminocyclohexyl)methane, bis(N,N-dicyclooxypropyl-2-methyl-4-aminocyclohexyl)methane, bis(N,N-dicyclooxypropyl-3-methyl-4-aminocyclohexyl)methane, 1,3-bis(N,N-dicyclooxypropylaminomethyl)cyclohexane, 1,4 Compounds containing tertiary nitrogen atoms and aliphatic carbon atoms bonded by tertiary nitrogen atoms, such as bis(N,N-dicyclooxypropylaminomethyl)cyclohexane, 1,3-bis(N,N-dicyclooxypropylaminomethyl)benzene, 1,4-bis(N,N-dicyclooxypropylaminomethyl)benzene, 1,3,5-tris(N,N-dicyclooxypropylaminomethyl)cyclohexane, and 1,3,5-tris(N,N-dicyclooxypropylaminomethyl)benzene; isocyanurate compounds such as tricyclooxypropyl isocyanate produced by Nissan Chemical Co., Ltd.; compounds described in paragraph

[0037] of Japanese Patent Application Publication No. 10-338880; and compounds described in International Patent Publication No. 2017 / 170483; Compounds containing oxetane groups include 1,4-bis{[(3-ethyl-3-oxetane)methoxy]methyl}benzene (ARON OXETANE OXT-121(XDO)), di[2-(3-oxetane)butyl] ether (ARON OXETANE OXT-221(DOX)), 1,4-bis[(3-ethyloxetane-3-yl)methoxy]benzene (HQOX), 1,3-bis[(3-ethyloxetane-3-yl)methoxy]benzene (RSOX), 1,2-bis[(3-ethyloxetane-3-yl)methoxy]benzene (CTOX), and compounds containing two or more oxetane groups as described in paragraphs

[0170] to

[0175] of International Publication No. 2011 / 132751. Compounds having an acezoline structure include compounds such as 2,2'-bis(2-acezoline), 2,2'-bis(4-methyl-2-acezoline), polymers and oligomers of EPOCROS (trade name, manufactured by Nippon Shokubai Co., Ltd.) with an acezoline group, and compounds described in paragraph

[0115] of Japanese Patent Application Publication No. 2007-286597; Compounds having a cyclic carbonate group include N,N,N',N'-tetratetra[(2-sideoxy-1,3-dioxolane-4-yl)methyl]-4,4'-diaminodiphenylmethane, N,N'-di[(2-sideoxy-1,3-dioxolane-4-yl)methyl]-1,3-phenylenediamine, and compounds described in paragraphs

[0025] to

[0030] and

[0032] of WO2011 / 155577, etc. Compounds having capped isocyanate groups include CORONATEAP Stable M, CORONATE2503, 2515, 2507, 2513, 2555, MILLIONATEMS-50 (all manufactured by Tosoh Corporation), TAKENATEB-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (all manufactured by Mitsui Chemicals Corporation), compounds having two or more protected isocyanate groups as described in paragraphs

[0046] to

[0047] of Japanese Patent Application Publication No. 2014-224978, and compounds having three or more protected isocyanate groups as described in paragraphs

[0119] to

[0120] of WO2015 / 141598, etc. Compounds having hydroxyl and / or alkoxy groups include N,N,N',N'-tetra(2-hydroxyethyl)hexamethylenediamine, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethoxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1,1,3,3,3-hexafluoropropane, compounds described in paragraph

[0058] of International Publication No. 2015 / 072554, Japanese Patent Application Publication No. 2016-118753, compounds described in Japanese Patent Application Publication No. 2016-200798, and compounds described in International Publication No. 2010 / 074269, etc. Crosslinked compounds with polymerizable unsaturated groups include glycerol mono(meth)acrylate, glycerol di(meth)acrylate (a mixture of 1,2- and 1,3-dimeth)acrylate, glycerol tri(meth)acrylate, glycerol 1,3-diglyceric acid di(meth)acrylate, neopentyl tert-ol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate, hexaethylene glycol mono(meth)acrylate, etc.

[0071] The liquid crystal alignment agent of the present invention contains a compound with a specific crosslinking group, which is preferably 0.1 to 30 parts by mass relative to 100 parts by mass of the total polymer components contained in the liquid crystal alignment agent, more preferably 0.1 to 20 parts by mass, and even more preferably 1 to 10 parts by mass.

[0072] Compounds used to adjust dielectric constant and resistance include monoamines such as 3-pyridinemethylamine, which have nitrogen-containing aromatic heterocycles. When using monoamines with nitrogen-containing aromatic heterocycles, it is preferable to use 0.1 to 30 parts by mass relative to 100 parts by mass of polymer components contained in the liquid crystal alignment agent, and more preferably 0.1 to 20 parts by mass.

[0073] Ideal examples of functional silane compounds include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-epoxypropoxypropylmethyldimethoxysilane. 3-Epoxypropoxypropyltrimethoxysilane, 3-Epoxypropoxypropylmethyldiethoxysilane, 3-Epoxypropoxypropyltriethoxysilane, p-Styrenetrimethoxysilane, 3-Methylpropoxypropylmethyldiethoxysilane, 3-Methylpropoxypropylmethyldiethoxysilane, 3-Methylpropoxypropylmethyldiethoxysilane, 3-Methylpropoxypropyltriethoxysilane, 3-Propylenepropoxypropyltrimethoxysilane, Tris(3-(trimethoxysilyl)propyl)isocyanurate, 3-Mercaptopropylmethyldiethoxysilane, 3-Mercaptopropyltrimethoxysilane, 3-Isocyanatepropyltriethoxysilane, etc. When using functional silane compounds, it is preferable to use 0.1 to 30 parts by mass relative to 100 parts by mass of polymer components contained in the liquid crystal alignment agent, and more preferably 0.1 to 20 parts by mass.

[0074] The organic solvents used in the liquid crystal alignment agent of this invention include lactone solvents such as γ-pentanolide and γ-butyrolactone; γ-butyrolactone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-n-propyl-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-n-butyl-2-pyrrolidone, N-tert-butyl-2-pyrrolidone, N-n-pentyl-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, and N-ethoxyethyl... -2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone and other acetamide solvents; N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-dimethylpropanediamide, N,N-diethylpropanediamide, N,N-dimethyllactamide, 3-methoxy-N,N-dimethylpropanediamide, 3-butoxy-N,N-dimethylpropanediamide, tetramethylurea and other acetamide solvents; cyclohexyl-2-pyrrolidone Ketones, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol monobutyl ether (butyl ceroxox), ethylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether ... Diethylene glycol monobutyl ether, propylene glycol diacetate, 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, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, diisobutylmethanol (2,6-dimethyl-4-heptanol), diisobutyl ketone (2,6-dimethyl-4-heptanone), isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, ethyl acetate, propyl acetate, etc. Two or more of these can be mixed.

[0075] Ideal solvent combinations include N-methyl-2-pyrrolidone with ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone with γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone with γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone with propylene glycol monobutyl ether, N-methyl-2-pyrrolidone with γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone with diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone with N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone, N-methyl-2-pyrrolidone with 4-hydroxy-4-methyl-2-pentanone and diisobutyl ketone, and N-methyl-2-pyrrolidone with 4-hydroxy-4-methyl-2-pentanone and dipropylene glycol monomethyl ether. N-methyl-2-pyrrolidone with 4-hydroxy-4-methyl-2-pentanone with propylene glycol monobutyl ether, N-methyl-2-pyrrolidone with 4-hydroxy-4-methyl-2-pentanone with propylene glycol diacetate, γ-butyrolactone with 4-hydroxy-4-methyl-2-pentanone with diisobutyl ketone, γ-butyrolactone with 4-hydroxy-4-methyl-2-pentanone with propylene glycol diacetate, N-methyl-2-pyrrolidone with γ-butyrolactone with propylene glycol monobutyl ether with diisobutyl ketone, N-methyl-2-pyrrolidone with γ-butyrolactone with propylene glycol monobutyl ether with diisopropyl ether, N-methyl-2-pyrrolidone with γ-butyrolactone with propylene glycol monobutyl ether with diisobutylmethanol, N-methyl-2-pyrrolidone with γ-butyrolactone with dipropylene glycol dimethyl ether, N -Methyl-2-pyrrolidone with propylene glycol monobutyl ether and dipropylene glycol dimethyl ether, cyclohexanone with ethylene glycol monobutyl ether, cyclohexanone with propylene glycol monobutyl ether, cyclohexanone with propylene glycol monomethyl ether, cyclopentanone with propylene glycol monobutyl ether, cyclopentanone with propylene glycol monomethyl ether, cyclohexanone with diethylene glycol monoethyl ether, cyclopentanone with diethylene glycol monoethyl ether, cyclohexanone with diisobutyl ketone, cyclopentanone with diisobutyl ketone, methyl isobutyl ketone with propylene glycol monobutyl ether, methyl ethyl ketone with propylene glycol monobutyl ether, cyclohexanone with 4-hydroxy-4-methyl-2-pentanone, cyclopentanone with 4-hydroxy-4-methyl-2-pentanone, cyclohexanone with diethylene glycol diethyl ether, cyclopentanone with diethylene glycol diethyl ether, tetramethylurea with propylene glycol diacetate, N,N-dimethylpropionylamine with propylene glycol monobutyl ether, tetramethyl Urea with propylene glycol monobutyl ether, tetramethylurea with cyclohexanone with propylene glycol monomethyl ether, N,N-dimethylpropionic acid with propylene glycol monomethyl ether, N,N-dimethylpropionic acid with ethylene glycol monobutyl ether acetate, N,N-dimethylpropionic acid with ethylene glycol monobutyl ether, N,N-diethylpropionic acid with propylene glycol monomethyl ether, tetramethylurea with propylene glycol monomethyl ether, N,N-dimethylpropionic acid with cyclohexanone with diethylene glycol diethyl ether, N,N-diethylmethionic acid with propylene glycol monomethyl ether, N,N-diethylmethionic acid with 4-hydroxy-4-methyl-2-pentanone, cyclohexanone with n-butyl acetate, cyclopentanone with n-butyl acetate, 4-hydroxy-4-methyl-2-pentanone with ethylene glycol monobutyl ether, cyclohexanone with propylene glycol diacetate, and cyclopentanone with propylene glycol diacetate, etc.The type and amount of such solvent can be appropriately selected according to the coating equipment, coating conditions, and coating environment of the liquid crystal alignment agent.

[0076] The concentration of solids in the liquid crystal alignment agent (the proportion of the total mass of components other than the solvent to the total mass of the liquid crystal alignment agent) can be appropriately selected considering factors such as viscosity and volatility, and is preferably in the range of 1 to 10% by mass. From the perspective of forming a uniform and defect-free coating, a concentration of 1% by mass or higher is ideal; from the perspective of the storage stability of the solution, a concentration of 10% by mass or lower is preferable. An ideal solids concentration is particularly high, ranging from 2 to 8% by mass.

[0077] <Liquid crystal alignment film> The liquid crystal alignment film of the present invention is obtained from the aforementioned liquid crystal alignment agent. The liquid crystal alignment film of the present invention can be a horizontally aligned or vertically aligned liquid crystal alignment film. Regarding vertically aligned liquid crystal alignment films, those used in vertically aligned liquid crystal display elements such as VA or PSA types are preferred.

[0078] Liquid crystal display element The liquid crystal display element of the present invention includes the above-described liquid crystal alignment film. The liquid crystal alignment agent of the present invention, having a liquid crystal layer between a pair of substrates having electrodes, and by disposing a liquid crystal composition containing a polymerizable compound that polymerizes due to at least one of active energy rays and heat between the pair of substrates, and by applying a voltage between the electrodes while simultaneously applying at least one of active energy irradiation and heating to polymerize the polymerizable compound, can also ideally be used as a liquid crystal display element.

[0079] The liquid crystal display element of the present invention can be manufactured by, for example, performing the following steps (1) to (3) or steps (1) to (4) in sequence. (1) The step of coating a liquid crystal alignment agent onto at least one of a pair of substrates having a conductive film to form a coating film. On one side of at least one of a pair of substrates having a patterned transparent conductive film, the liquid crystal alignment agent of the present invention is coated using a suitable coating method, such as roll coating, spin coating, printing, or inkjet coating, to form a coating film. Here, the substrate is not particularly limited to any substrate with high transparency; it can also be used simultaneously with glass substrates, silicon nitride substrates, acrylic substrates, polycarbonate substrates, or other plastic substrates. Furthermore, if the reflective liquid crystal display element is only one substrate, an opaque material such as a silicon wafer can be used, and the electrodes can be made of light-reflecting materials such as aluminum.

[0080] (2) The step of calcining the coating film. After the liquid crystal alignment agent is coated, the coating is calcined to prevent dripping of the coated liquid crystal alignment agent. Pre-heating (pre-baking) is preferred. The pre-baking temperature is preferably 30-200°C, more preferably 40-150°C, and even more preferably 40-100°C. The pre-baking time is preferably 0.25-10 minutes, more preferably 0.5-5 minutes. A post-baking step is then performed. The post-baking temperature is preferably 80-300°C, more preferably 120-250°C. The post-baking time is preferably 5-200 minutes, more preferably 10-100 minutes. The film thickness formed in this manner is ideally 5-300 nm, and more preferably 10-200 nm.

[0081] The coating formed by the above steps (1) and (2) can be used directly as a liquid crystal alignment film, or the coating can be subjected to alignment capability imparting treatment. Alignment capability imparting treatment can include friction treatment, which involves rubbing the coating in a certain direction with a roller wrapped with a cloth made of fibers such as nylon, silk, or cotton, and photoalignment treatment, which involves irradiating the coating with polarized or unpolarized radiation.

[0082] In photoalignment processing, the radiation used to irradiate the coating can be, for example, ultraviolet light or visible light containing wavelengths of 150-800 nm. When the radiation is polarized, it can be linearly polarized or partially polarized. Furthermore, when using linearly polarized or partially polarized radiation, irradiation can be performed perpendicular to the substrate surface, obliquely, or a combination thereof. When irradiating unpolarized radiation, the irradiation direction is set to oblique.

[0083] (3) Step of forming a liquid crystal layer between the above-mentioned pair of substrates to fabricate a liquid crystal cell. (3-1) When manufacturing VA-type liquid crystal display elements As described above, two substrates are prepared in which at least one of the two substrates forms the liquid crystal alignment film of the present invention, and liquid crystal is disposed between the two opposing substrates. Specifically, the following two methods can be listed. The first method is a conventionally known method. First, the two substrates are arranged facing each other with gaps (cell gaps) separated by each liquid crystal alignment film surface. Then, a sealant is applied to the periphery of the two substrates and they are bonded together. After the liquid crystal composition is injected into the cell gaps separated by the substrate surface and the sealant and comes into contact with the film surface, the injection hole is sealed.

[0084] The second method is called the ODF (One Drop Fill) method. A UV-curable sealant, for example, is applied to predetermined areas on one of the two substrates on which the liquid crystal alignment film has already been formed. Then, liquid crystal composition is dropped onto predetermined points on the surface of the liquid crystal alignment film. Next, the other substrate is bonded together with the liquid crystal alignment film faces facing each other, pressing the liquid crystal composition onto the entire substrate so that it contacts the film surface. Finally, the entire substrate is irradiated with UV light to harden the sealant. In either case, the liquid crystal composition is heated further until it reaches the temperature of the isotropic phase, and then slowly cooled to room temperature to remove the flow alignment during liquid crystal filling for a more ideal result.

[0085] There are no special restrictions on the liquid crystal composition mentioned above. Various liquid crystal compositions containing at least one liquid crystal compound (liquid crystal molecule) and having positive or negative dielectric anisotropy can be used. Furthermore, liquid crystal compositions with positive dielectric anisotropy are referred to as positive liquid crystals, and liquid crystal compositions with negative dielectric anisotropy are referred to as negative liquid crystals. The aforementioned liquid crystal composition may also contain liquid crystal compounds having fluorine atoms, hydroxyl groups, amino groups, fluorine-containing groups (e.g., trifluoromethyl), cyano groups, alkyl groups, alkoxy groups, alkenyl groups, isothiocyanate groups, heterocyclic groups, cycloalkanes, cycloalkenes, steroid skeletons, benzene rings, or naphthyl rings. It may also contain compounds with two or more rigid sites exhibiting liquid crystal properties (mesogen skeletons) within the molecule (e.g., rigid biphenyl structures, or biphenyl structures linked by alkyl groups in a double mesosome skeleton). The liquid crystal composition may be a nematic phase liquid crystal composition, a lamellar phase liquid crystal composition, or a cholesterol phase liquid crystal composition. Furthermore, in order to improve the alignment of the liquid crystal, additives may be added to the above-mentioned liquid crystal composition. Such additives include photopolymerizable monomers such as compounds with polymerizable groups; optically active compounds (e.g., S-811 manufactured by Merck); antioxidants; ultraviolet absorbers; pigments; defoamers; polymerization initiators; or polymerization inhibitors. Positive liquid crystal displays, such as Merck's ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, or MLC-7081, etc. Negative liquid crystal displays, such as MLC-6608, MLC-6609, MLC-6610, MLC-6882, MLC-6886, MLC-7026, MLC-7026-000, MLC-7026-100, or MLC-7029 manufactured by Merck. Furthermore, in the PSA process, an example of a liquid crystal containing a compound with polymerizable groups is MLC-3023 manufactured by Merck.

[0086] (3-2) Manufacturing of liquid crystal display elements using the PSA method Except for injecting or dropping a liquid crystal composition containing a compound with a polymerizable group, the process is the same as described in (3-1). The compound with a polymerizable group is, for example, a compound having a liquid crystal precursor structure and two or more photopolymerizable or thermally polymerizable groups. Examples of liquid crystal precursor structures include structures formed by the linkage of two or more aromatic or aliphatic groups, such as biphenyl structures, terphenyl structures, naphthalene rings, groups with two hydroxyl groups removed from bisphenol A, or structures where one of the hydrogen atoms is replaced by a fluorine atom. Specific examples of compounds include 4,4'-dimethylpropenyloxybiphenyl, or 3-fluoro-1,1'-biphenyl-4,4'-dimethyldimethacrylate.

[0087] (3-3) Case where a coating is formed on a substrate using a liquid crystal alignment agent containing a compound with polymerizable groups. Alternatively, a method similar to (3-1) above, followed by ultraviolet irradiation as described later, can be used to manufacture a liquid crystal display element. Using this method, similar to manufacturing a PSA-type liquid crystal display element, a liquid crystal display element with excellent response speed can be obtained with a low light irradiation amount. The compound having a polymerizable group can also be a compound having the aforementioned polymerizable group, and its content relative to 100 parts by mass of the total polymer component is preferably 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass. Furthermore, the aforementioned polymerizable group can be possessed by the polymer used as a liquid crystal alignment agent, such as a polymer obtained by using a diamine component containing a diamine terminally having the aforementioned photopolymerizable group in the reaction.

[0088] (4) Steps for irradiating liquid crystal cells The liquid crystal cells are irradiated by applying a voltage between the conductive films on the substrate as obtained in either (3-2) or (3-3) above. The applied voltage can be, for example, DC or AC of 5-50V. The irradiated light can be, for example, ultraviolet light or visible light containing wavelengths of 150-800nm, but ultraviolet light containing wavelengths of 300-400nm is preferred. The light source can be, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonant lamp, a xenon lamp, or an excimer laser. The irradiation intensity is preferably 1,000-200,000 J / m², more preferably 1,000-100,000 J / m².

[0089] Furthermore, a liquid crystal display element can be obtained by attaching a polarizing plate to the outer surface of the liquid crystal cell. Examples of polarizing plates attached to the outer surface of the liquid crystal cell include: polarizing plates made of a polarizing film called "H film" by extending polyvinyl alcohol to absorb iodine through a cellulose acetate protective film clamping the edges, or polarizing plates composed of the H film itself.

[0090] The liquid crystal display element of this invention can be effectively applied to various devices, such as: watches, portable game consoles, word processors, laptops, navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, various screens, LCD TVs, information displays, and other display devices. Furthermore, the aforementioned liquid crystal alignment agent can also be used in liquid crystal alignment films for phase retardation films, liquid crystal alignment films for scanning antennas, liquid crystal array antennas, or liquid crystal alignment films for transmission-scattering type liquid crystal dimming elements, or for other applications, such as protective films for color filters, gate insulating films for flexible displays, and substrate materials. [Example]

[0091] The following examples illustrate the present invention in detail, but the invention is not limited to these examples. The abbreviations of the compounds and the methods for determining their properties are as follows.

[0092] (Organic solvents) THF: Tetrahydrofuran NMP: N-methyl-2-pyrrolidone BCS: Butylcerox (ethylene glycol monobutyl ether)

[0093] (Tetracarboxylic acid dianhydride) (CA-1)~(CA-3): Each is a compound represented by the formula (CA-1)~(CA-3). [Chemistry 22]

[0094] (Diamine) (DA-1)~(DA-12): Each is a compound represented by the formulas (DA-1)~(DA-12). [Chemistry 23]

[0095] <Viscosity Measurement> The viscometer was a TVE-22H (manufactured by Toki Sangyo Co., Ltd.), with a sample volume of 1.1 mL and a conical rotor TE-1 (1°34', R24), and the measurement was performed at a temperature of 25°C.

[0096] <Determination of Molecular Weight> The following room-temperature gel permeation chromatography (GPC) apparatus was used to determine and calculate the number average molecular weight (Mn) and weight average molecular weight (Mw) as conversion values ​​for polyethylene glycol and polyethylene oxide. GPC device: GPC-101 (manufactured by Showa Denko Corporation) Series connection of GPC KD-803 and GPC KD-805 (manufactured by Showa Denko Corporation) Column temperature: 50℃ Dissolution solution: N,N-dimethylformamide (additives: lithium bromide monohydrate (LiBr·H₂O) 30 mmol / L, anhydrous phosphoric acid crystals (orthophosphoric acid) 30 mmol / L, tetrahydrofuran (THF) 10 mL / L) Flow rate: 1.0 mL / min Standard samples used for the measurement line: TSK standard polyethylene oxide (molecular weight; approx. 900,000, 150,000, 100,000 and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight; approx. 12,000, 4,000 and 1,000) (manufactured by Polymer Laboratory Corporation).

[0097] Synthesis of specific diamines (DA-4) to (DA-5) The synthetic methods for the compounds represented by formulas (DA-4) to (DA-5) are detailed below. Furthermore, the compounds represented by formulas (DA-4) to (DA-5) are novel compounds not disclosed in the literature.

[0098] <Determination by 1H-NMR> Apparatus: Fourier transform superconducting nuclear magnetic resonance (FT-NMR) system "Varian NMR System 400NB" (Varian) 400MHz, "AVANCE III" (BRUKER) 500MHz. Solvent: Deuterated dimethyl monoxide (DMSO-d6; Standard substance: Tetramethylsilane).

[0099] <Synthesis Example 1-1: Synthesis of DA-4> (Synthesis of DA-4-1) [Chemistry 24]

[0100] 3,5-Dinitrobenzyl alcohol (19.9 g, 100 mmol), THF (118 g), and triethylamine (12.5 g, 123 mmol) were charged into a 500 mL four-necked flask. After cooling to 5 °C in an ice bath, methanesulfonyl chloride (12.5 g, 109 mmol) was added dropwise. After the reaction was complete, the precipitated triethylamine salt was removed by filtration. The filtrate was concentrated to obtain crude DA-4-1. The mixture of crude DA-4-1 and 2-propanol (68.0 g) was stirred in a slurry at 80 °C for 1 hour. After cooling to room temperature, the crystals were recovered by filtration. The recovered crystals were dried under vacuum at 50 °C to obtain DA-4-1 (yield: 20.9 g, 75.6 mmol, 75.6% yield, yellow solid).

[0101] (Synthesis of DA-4-2) [Chemistry 25]

[0102] DA-4-1 (14.0 g, 50.7 mmol), potassium carbonate (12.4 g, 90.0 mmol), hydroquinone (90.6 g, 823 mmol), and ethanol (362 g) were added to a 1 L four-necked flask and reacted at 45 °C for 5 hours. After the reaction, the reaction solution and water (1200 g) were added to a 2 L beaker, causing crude DA-4-2 to precipitate. The precipitate was recovered by filtration and dried under vacuum at 50 °C. Methanol (350 g) and ethanol (190 g) were added to the crude DA-4-2 and heated to 60 °C to dissolve it. Insoluble matter was removed by filtration, and water (1000 g) was added to the filtrate to precipitate DA-4-2. The precipitated solid was recovered by filtration and dried under vacuum at 50 °C to obtain DA-4-2 (yield: 10.0 g, 34.5 mmol, 68.0%, yellow solid).

[0103] (Synthesis of DA-4) [Chemistry 26]

[0104] DA-4-2 (9.98 g, 34.4 mmol), THF (120 g), and carbon-supported platinum (3% by mass, 0.500 g) were added to a 500 mL four-necked flask and reacted at room temperature under hydrogen atmosphere. After the reaction was complete, the carbon-supported platinum was removed by filtration. The filtrate was concentrated, and the precipitated crystals were dried under vacuum at 50 °C to obtain DA-4 (yield: 7.71 g, 33.5 mmol, yield: 97.4%, orange solid). The 1H-NMR results shown below confirmed that this solid was DA-4. 1H-NMR (500MHz, DMSO-d 6): δ (ppm) = 8.86 (s, 1H), 6.75 (d, 2H, J = 9.0Hz), 6.64 (d, 2H, J = 9.0Hz), 5.83 (d, 2H, J = 1.9Hz), 5.74 (t, 1H, J=2.0Hz),4.71(br,4H),4.66(s,2H).

[0105] <Synthesis Example 1-2: Synthesis of DA-5> The diamine DA-5 was synthesized via the route shown below. [Chemistry 27]

[0106] (Synthesis of DA-5-1) Tetrahydrofuran (361 g), ethyl 3,4-dihydroxybenzoate (90.2 g, 495 mmol), and N,N-diisopropylethylamine (iPr 2EtN, 320 g, 2.48 mol) were placed in a 2000 mL four-necked flask. Chloromethyl ether (MOMCl, 179 g, 2.22 mol) was added dropwise under nitrogen atmosphere and ice-cold conditions. The reaction was allowed to proceed at room temperature until the reactants disappeared. After the reaction was complete, the reaction solution was diluted with ethyl acetate (1350 g) and the organic phase was washed with pure water (720 g). The organic phase was then washed twice with 2.0 mol / L hydrochloric acid solution (720 g) and three times with pure water (720 g). The obtained organic phase was concentrated under reduced pressure to obtain a pale yellow oily crude product. Ethanol (400 g) and pure water (274 g) were added to the crude product, followed by sodium hydroxide (21.8 g). The mixture was allowed to react at room temperature for 20 hours to hydrolyze the product. After the reaction was complete, 1.0 mol / L hydrochloric acid aqueous solution (600 mL) was added to the reaction solution to induce crystallization. Pure water (266 g) was then added to wash the slurry. The mixture was then filtered, and the filter was washed with pure water and hexane and dried to obtain DA-5-1 (yield: 111 g, 458 mmol, yield: 93%, white crystals).

[0107] (Synthesis of DA-5-2) In a 2000 mL four-necked flask, 3,5-dinitrobenzyl alcohol (75.2 g, 379 mmol), DA-5-1 (106 g, 438 mmol), 4-dimethylaminopyridine (DMAP, 4.62 g), and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC, 94.5 g) were added to tetrahydrofuran (452 ​​g) and reacted at room temperature under nitrogen atmosphere for 4 hours. After the reaction was completed, the reaction solution was injected into pure water (810 g) to induce crystallization. The mixture was filtered, and the filtrate was washed with pure water and then with methanol. The resulting filtrate was then washed with methanol (180 g), filtered, and dried to obtain DA-5-2 (yield: 156 g, 369 mmol, yield: 97%, pale yellow crystals).

[0108] (Synthesis of DA-5-3) In a 2000 mL four-necked flask, 200 g of 4.0 mol / L hydrochloric acid aqueous solution and DA-5-2 (131 g, 310 mmol) were added to tetrahydrofuran (195 g) and methanol (MeOH, 327 g), and the mixture was heated at 50 °C for approximately 12 hours. After the reaction was complete, 1310 g of ethyl acetate and 432 g of toluene were added to the reaction solution to separate the two phases. After removing the hydrochloric acid phase, the organic layer was washed three times with pure water (400 g). The organic phase was concentrated under reduced pressure to a total internal weight of 555 g, and 2-propanol (262 g) was added and stirred under ice-cold conditions to induce crystallization. The precipitated crystals were filtered and dried to obtain DA-5-3 (yield: 80.3 g, 240 mmol, 78% yield, yellow crystals).

[0109] (Synthesis of DA-5) In a 1000 mL four-necked flask, DA-5-3 (39.2 g, 117 mmol) and carbon-supported platinum (3.13 g by mass) were added to tetrahydrofuran (240 g) and methanol (80 g). The mixture was heated at 40 °C under hydrogen atmosphere for 2 days. After the reaction was complete, the mixture was filtered and concentrated under reduced pressure to a total internal weight of 35 g. Then, methanol (120 g) was added to induce crystallization. The crystals were filtered and dried to obtain DA-5 (yield: 28.0 g, 102 mmol, yield: 87%, pale yellow crystals). The 1H-NMR results shown below confirm that this solid is DA-5. 1H-NMR (400MHz, DMSO-d 6): δ (ppm) = 9.60 (s, 2H), 7.38 (s, 1H), 7.32-7.38 (m, 1H), 6.81 (d, 1H, J = 8.0Hz), 5.83 (d, 2H, J=1.6Hz),5.76-5.77(m,1H),4.96(s,2H),4.78(s,4H)

[0110] [Polymer Synthesis] <Synthesis example 2-1> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-1 (2.97 g, 10.0 mmol), DA-4 (0.921 g, 4.00 mmol), DA-6 (2.28 g, 6.00 mmol), CA-1 (2.50 g, 10.0 mmol), and NMP (34.7 g) were added, and the mixture was stirred at 60 °C for 3 hours while introducing nitrogen. Then, CA-2 (1.80 g, 9.20 mmol) and NMP (7.22 g) were added, and the mixture was stirred at 40 °C for 3 hours to obtain a polyacrylic acid solution (1) with a solid content of 20% by mass (viscosity: 690 mPa·s). The Mn of this polyacrylic acid was 12,400, and the Mw was 28,500.

[0111] <Synthesis example 2-2> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-1 (2.97 g, 10.0 mmol), DA-2 (0.893 g, 4.00 mmol), DA-6 (2.28 g, 6.00 mmol), CA-1 (2.50 g, 10.00 mmol), and NMP (34.8 g) were added, and the mixture was stirred at 60 °C for 3 hours while introducing nitrogen. Then, CA-2 (1.93 g, 9.84 mmol) and NMP (7.72 g) were added, and the mixture was stirred at 40 °C for 3 hours to obtain a polyacrylic acid solution (2) with a solid content of 20% by mass (viscosity: 720 mPa·s). The Mn of this polyacrylic acid was 15,600, and the Mw was 32,800.

[0112] <Synthesis example 2-3> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-1 (2.97 g, 10.0 mmol), DA-5 (1.10 g, 4.00 mmol), DA-6 (2.28 g, 6.00 mmol), CA-1 (2.50 g, 10.00 mmol), and NMP (35.4 g) were added, and the mixture was stirred at 60 °C for 3 hours while introducing nitrogen. Then, CA-2 (1.91 g, 9.74 mmol) and NMP (7.62 g) were added, and the mixture was stirred at 40 °C for 3 hours to obtain a polyacrylic acid solution (3) with a solid content of 20% by mass (viscosity: 680 mPa·s). The Mn of this polyacrylic acid was 16,800, and the Mw was 32,200.

[0113] <Synthesis example 2-4> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-8 (0.793 g, 4.00 mmol), DA-4 (0.921 g, 4.00 mmol), DA-9 (2.46 g, 6.00 mmol), DA-10 (1.45 g, 6.00 mmol), CA-2 (3.02 g, 15.4 mmol), and NMP (34.6 g) were added. The mixture was stirred at 40 °C for 3 hours while introducing nitrogen. Then, CA-3 (0.872 g, 4.00 mmol) and NMP (3.49 g) were added, and the mixture was stirred at room temperature for 3 hours to obtain a polyacrylic acid solution (4) with a solid content of 20% by mass (viscosity: 780 mPa·s). The Mn of this polyacrylic acid was 16,800, and the Mw was 32,400.

[0114] <Synthesis example 2-5> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-8 (0.793 g, 4.00 mmol), DA-2 (0.893 g, 4.00 mmol), DA-9 (2.46 g, 6.00 mmol), DA-10 (1.45 g, 6.00 mmol), and CA-2 (3.02 g, 15.4 mmol) were added, and the mixture was stirred at 40 °C for 3 hours while introducing nitrogen. Then, NMP (34.7 g), CA-3 (0.872 g, 4.00 mmol), and NMP (3.49 g) were added, and the mixture was stirred at room temperature for 3 hours to obtain a polyacrylic acid solution (5) with a solid content of 20% by mass (viscosity: 740 mPa·s). The Mn of this polyacrylic acid was 12,900, and the Mw was 23,900.

[0115] <Synthesis example 2-6> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-8 (0.793 g, 4.00 mmol), DA-3 (1.13 g, 4.00 mmol), DA-9 (2.46 g, 6.00 mmol), DA-10 (1.45 g, 6.00 mmol), CA-2 (3.02 g, 15.4 mmol), and NMP (34.4 g) were added. The mixture was stirred at 40 °C for 3 hours while introducing nitrogen. Then, CA-3 (0.872 g, 4.00 mmol) and NMP (3.49 g) were added, and the mixture was stirred at room temperature for 3 hours to obtain a polyacrylic acid solution (6) with a solid content of 20% by mass (viscosity: 745 mPa·s). The Mn of this polyacrylic acid was 11,500, and the Mw was 23,400.

[0116] <Synthesis example 2-7> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-1 (2.97 g, 10.0 mmol), DA-6 (2.28 g, 6.00 mmol), DA-12 (0.609 g, 4.00 mmol), CA-1 (2.50 g, 10.0 mmol), and NMP (33.5 g) were added, and the mixture was stirred at 60 °C for 3 hours while introducing nitrogen. Then, CA-2 (1.80 g, 9.20 mmol) and NMP (7.22 g) were added, and the mixture was stirred at 40 °C for 3 hours to obtain a polyacrylic acid solution (7) with a solid content of 20% by mass (viscosity: 650 mPa·s). The Mn of this polyacrylic acid was 11,900, and the Mw was 25,600.

[0117] <Synthesis example 2-8> In a 50 mL four-necked flask equipped with a stirrer and a nitrogen inlet tube, DA-1 (2.08 g, 7.00 mmol), DA-7 (2.61 g, 6.00 mmol), DA-10 (0.969 g, 4.00 mmol), DA-11 (0.991 g, 3.00 mmol), CA-1 (2.50 g, 10.0 mmol), and NMP (36.6 g) were added. The mixture was stirred at 60 °C for 3 hours while introducing nitrogen. Then, CA-2 (1.86 g, 9.50 mmol) and NMP (7.45 g) were added, and the mixture was stirred at 40 °C for 3 hours to obtain a polyacrylic acid solution (8) with a solid content of 20% by mass (viscosity: 690 mPa·s). The Mn of this polyacrylic acid was 10,900, and the Mw was 26,900.

[0118] The specifications of the polymers obtained from the above synthesis examples are shown in Table 1 below. [Table 1]

[0119] [Preparation of Liquid Crystal Alignment Agents] <Example 1-1> NMP (8.00 g) and BCS (8.00 g) were added to the polyamide solution (1) (4.00 g) obtained in Synthesis Example 2-1, and the mixture was stirred at room temperature for 3 hours to obtain the liquid crystal alignment agent (A-1).

[0120] <Examples 1-2~1-3, Comparative Example 1-1> Polyamide solution (2) to (3) and (7) were used instead of polyamide solution (1), and otherwise the same procedure as in Example 1-1 was performed to obtain the liquid crystal alignment agents (A-2) to (A-3) and (B-1) of Examples 1-2 to 1-3 and Comparative Example 1-1.

[0121] <Examples 1-4> NMP (8.00 g) and BCS (8.00 g) were added to the polyamide solution (8) (1.20 g) obtained in Synthesis Examples 2-8 and the polyamide solution (4) (2.80 g) obtained in Synthesis Examples 2-4, and the mixture was stirred at room temperature for 3 hours to obtain liquid crystal alignment agent (A-4).

[0122] <Examples 1-5~1-6> Instead of using polyamide solution (4), polyamide solutions (5) to (6) were used. Otherwise, the process was the same as in Examples 1-4 to obtain the liquid crystal alignment agents (A-5) to (A-6) of Examples 1-5 to 1-6.

[0123] The specifications of the liquid crystal alignment agents obtained in the above embodiments and comparative examples are shown in Table 2 below. [Table 2] Liquid crystal alignment agent polymer components Example 1-1 A-1 Polyamide solution (1) Examples 1-2 A-2 Polyamide solution (2) Examples 1-3 A-3 Polyamide solution (3) Examples 1-4 A-4 Polyamide solution (8), polyamide solution (4) Examples 1-5 A-5 Polyamide solution (8), polyamide solution (5) Examples 1-6 A-6 Polyamide solution (8), polyamide solution (6) Comparative Example 1-1 B-1 Polyamide solution (7)

[0124] The liquid crystal alignment agents (A-1) to (A-6) and (B-1) obtained in the manner described above showed no abnormalities such as turbidity or precipitation, confirming that they were homogeneous solutions. The obtained liquid crystal alignment agents were used to evaluate the voltage retention rate.

[0125] Fabrication of liquid crystal cells for voltage retention evaluation Using the liquid crystal alignment agent obtained above, liquid crystal cells were fabricated according to the following procedure. The liquid crystal alignment agent was spin-coated onto a glass substrate (3cm wide × 4cm long) with an ITO electrode. After drying on a hot plate at 70°C for 90 seconds, it was calcined in an infrared furnace at 230°C for 20 minutes to form a liquid crystal alignment film with a thickness of 100nm. Two substrates with the liquid crystal alignment film were prepared. On one substrate, 4μm diameter bead spacers (made by Nichibukai Chemical Co., Ltd., silk balls, SW-D1) were coated onto the liquid crystal alignment film. A thermosetting sealant (made by Mitsui Chemicals Co., Ltd., XN-1500T) was printed around the liquid crystal injection port. Then, the side of the other substrate with the formed liquid crystal alignment film was used as the inner side, and it was bonded to the first substrate. The sealant was then hardened to create a void. Liquid crystal MLC-3023 (made by Merck) was injected into this void using a depressurized injection method to form a liquid crystal cell. Then, with a DC voltage of 15V applied to the liquid crystal cell, UV light of 10J / cm², filtered through a cutoff filter with a wavelength of 325nm or less, was irradiated from the outside of the liquid crystal cell. The UV irradiance was measured using an ORC UV-MO3A photometer. Afterwards, to deactivate any unreacted polymeric compounds remaining in the liquid crystal cell, UV light (UV lamp: FLR40SUV32 / A-1) was applied for 30 minutes without voltage applied using a TOSHBA LIGHTECH UV-FL irradiation device (hereinafter also referred to as PSA treatment).

[0126] [Evaluation of Voltage Holding Rate] Voltage retention rate was determined using liquid crystal cells for evaluating voltage retention after PSA treatment. A voltage of 1V was applied for 60μsec in a 60°C hot air circulating oven, and the voltage was measured after 1667ms. The voltage retained was calculated and defined as the voltage retention rate. The voltage retention rate was measured using a VHR-1 meter manufactured by TOYO TECHNICA. A higher value is better. The evaluation criteria were: a voltage retention rate of 80% or higher after PSA treatment was rated as "0", and a rate below 80% was rated as "×".

[0127] [Evaluation of voltage retention rate after aging] The PSA-treated liquid crystal cells were placed in a high-temperature and high-humidity oven set at 60°C and 90% relative humidity for 10 days for curing. The voltage retention rate after curing was calculated in the same way as above. The evaluation criterion is that a voltage retention rate of 40% or higher after curing is rated as "0", and a rate of less than 40% is rated as "×".

[0128] [Table 3] Liquid crystal alignment agent Voltage holding rate (%) After PSA processing After maturation Example 1-1 A-1 84(〇) 48(〇) Examples 1-2 A-2 83(〇) 46(〇) Examples 1-3 A-3 82(〇) 48(〇) Examples 1-4 A-4 88(〇) 56(〇) Examples 1-5 A-5 86(〇) 50(〇) Examples 1-6 A-6 89(〇) 56(〇) Comparative Example 1-1 B-1 77(×) 35(×)

[0129] As shown in Table 3, the liquid crystal alignment films obtained using liquid crystal alignment agents (A-1) to (A-6) of Examples 1-1 to 1-6 showed higher voltage retention rates after PSA treatment and high temperature and high humidity curing compared to the liquid crystal alignment film obtained using liquid crystal alignment agent (B-1) of Comparative Example 1-1.

Claims

1. A liquid crystal alignment agent comprising a polymer component, wherein the polymer component meets at least one of the following conditions (i) and (ii): Condition (i): the polymer component comprises at least one polymer selected from the group consisting of a polyimide precursor having repeating units (a1) represented by formula (1) and repeating units (a1') represented by formula (1') and polyimides of the polyimide precursor. Condition (ii): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and a polyimide consisting of a polyimide of a polyimide precursor with a polyimide derivative thereof, and at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by the following formula (1') and a polyimide consisting of a polyimide precursor with a polyimide derivative thereof, where X1 and X1' each independently represent a tetravalent organic group, Y1 represents a divalent organic group having an acezoline skeleton, Y1' represents a divalent organic group having an aliphatic carboxyl group (Ah) or a divalent organic group having a phenolic hydroxyl group (ph), and R and Z each independently represent a hydrogen atom or a monovalent organic group.

2. The liquid crystal alignment agent as claimed in claim 1, wherein, The divalent organic group (ph) has the following structure (ph-1) as the structure of the phenolic hydroxyl group, where Ar represents a benzene ring or a naphthalene ring, R represents a hydrogen atom, methyl, methoxy, or halogen atom, and * represents an atomic bond. When Ar is a benzene ring, p represents an integer from 1 to 5, q represents an integer from 0 to 4, and r represents an integer from 1 to 5. The sum of p, q, and r is 6. When Ar is a naphthalene ring, p represents an integer from 1 to 7, q represents an integer from 0 to 6, and r represents an integer from 1 to 7. The sum of p, q, and r is 8.

3. The liquid crystal alignment agent as claimed in claim 1, wherein, The polymer component must at least meet condition (i).

4. The liquid crystal alignment agent as claimed in claim 1, wherein, The polymer component must at least meet this condition (ii).

5. The liquid crystal alignment agent as claimed in claim 1, wherein, The zozoline skeleton in Y1 is located in the main chain of a polymer having Y1.

6. The liquid crystal alignment agent as claimed in claim 1, wherein, Y1 has a substructure represented by the formula (m-Ox), and the substructure represented by the formula (m-Ox) is located in the main chain of the polymer having Y1, R1 represents a hydrogen atom or a monovalent organic group, and * represents an atomic bond.

7. The liquid crystal alignment agent as claimed in claim 1, wherein, In this aliphatic carboxyl group, the carbon atoms of the carboxyl group and the methylene group may form a carbon atom bond in an alicyclic structure.

8. The liquid crystal alignment agent as claimed in claim 1, wherein, The divalent organic group (Ah) is a diamine (Ah) from which two amino groups have been removed. The specific diamine (Ah) is an aromatic diamine represented by "A 1'-(L-Ah) m'" or "(A 11') 2-Ah'". A 1' represents a m' valence group with two primary amino groups bonded to an aromatic group, A 11' represents a monovalent group with one primary amino group bonded to an aromatic group, L represents a single bond, -O-, -CO-, -CO-O-, -NR-, or -NR-CO-, where R represents a hydrogen atom or a methyl group, Ah represents a monovalent aliphatic carboxyl group, m' is an integer from 1 to 2, and Ah' represents a divalent aliphatic carboxyl group.

9. The liquid crystal alignment agent as claimed in claim 1, wherein, The polymer composition meets at least one of the following conditions (i-1), (ii-1), and (ii-2): Condition (i-1): The polymer composition contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1), a repeating unit (a1') represented by formula (1'), and a repeating unit (a2) represented by formula (2), and a polyimide consisting of a polyimide of the polyimide precursor. Condition (ii-1): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) and a repeating unit (a2) represented by formula (2) and a polyimide consisting of a amide of the polyimide precursor, and at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by formula (1') and a polyimide consisting of a amide of the polyimide precursor, Condition (ii-2): The polymer component contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1) represented by formula (1) and a polyimide consisting of a polyimide of a polyimide precursor with a amide. It also contains at least one polymer selected from the group consisting of a polyimide precursor having a repeating unit (a1') represented by formula (1') and a repeating unit (a2) represented by formula (2) and a polyimide consisting of a polyimide of a polyimide precursor with a amide. X2 represents a tetravalent organic group, Y2 represents a divalent organic group having a group -XJ, and R and Z each independently represent a hydrogen atom or a monovalent organic group. In the group -XJ, X represents a single bond, -(CH2)a-, -CONH-, -NHCO-, or -CO-N(CH2)a-. 3) -, -NH-, -O-, -COO-, -OCO-, -Ak-O-CO-CH=CH-**, or -(A 1) a0-((CH 2) a1-A 1) m1-, where a is an integer from 1 to 15, ** represents an atomic bond with an aromatic hydrocarbon group, Ak represents a divalent organic group with 1 to 10 carbon atoms, a0 is an integer of 0 or 1, a1 is an integer from 1 to 15, A 1 independently represents -O- or -COO-, m1 is an integer from 1 to 2, when m1 is 2, multiple a1s independently have this definition. J represents a monovalent organic group having at least one group selected from the group consisting of alicyclic hydrocarbon groups with 4 to 40 carbon atoms and aromatic hydrocarbon groups with 6 to 40 carbon atoms, wherein at least one of the hydrogen atoms of the alicyclic hydrocarbon group and the aromatic hydrocarbon group is substituted by a halogen atom, an alkyl group containing a halogen atom with 1 to 10 carbon atoms, an alkoxy group containing a halogen atom with 1 to 10 carbon atoms, an alkyl group with 3 to 10 carbon atoms, an alkoxy group with 3 to 10 carbon atoms, or an alkenyl substituent (v) with 3 to 10 carbon atoms. Furthermore, any carbon-carbon single bond in such substituent (v) may be interrupted by -O-, except for the halogen atom.

10. The liquid crystal alignment agent as claimed in claim 1, wherein, The tetravalent organic groups in X1 and X1' are tetravalent organic groups derived from tetracarboxylic dianhydride or its derivatives, and the tetravalent organic groups are tetravalent organic groups derived from acyclic aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride, or their derivatives.

11. A liquid crystal alignment film obtained from a liquid crystal alignment agent as claimed in any one of claims 1 to 10.

12. A liquid crystal display element comprising a liquid crystal alignment film as claimed in claim 11.

13. A method for manufacturing a liquid crystal display element, comprising performing the following steps (1) to (3) in sequence: Step (1): applying a liquid crystal alignment agent as claimed in any one of claims 1 to 10 onto at least one of a pair of substrates having a conductive film to form a coating film; Step (2): calcining the coating film; Step (3): forming a liquid crystal layer between the pair of substrates to create a liquid crystal cell.

14. A method for manufacturing a liquid crystal display element as claimed in claim 13, comprising, after steps (1) to (3), performing the following step (4): irradiating the liquid crystal cell with light.