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

Abstract

The present invention provides: a liquid crystal alignment film in which generated charge can be reduced in a short time, while reducing the absolute value of accumulated charge; and a liquid crystal alignment agent that enables achievement of a liquid crystal alignment film in which flickering and charge accumulation attributable to the light of backlight are reduced.　Disclosed is a liquid crystal alignment agent which is characterized by containing at least one polymer (PO) that is selected from the group consisting of: a polyimide precursor having a partial structure (a0) represented by formula (0); and a polyimide that is an imidized product of the polyimide precursor. (In the formula, the definition of each symbol is as defined in the description.)

Description

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

[0001] The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film obtained from the liquid crystal aligning agent, a liquid crystal display device having the liquid crystal alignment film, and a novel diamine and polymer suitable for them.

[0002] Liquid crystal display elements are widely used as display units for personal computers, mobile phones, smartphones, televisions, etc. Liquid crystal display elements include, for example, a liquid crystal layer sandwiched between an element substrate and a color filter substrate, pixel electrodes and a common electrode that apply an electric field to the liquid crystal layer, an alignment film that controls the liquid crystal alignment of liquid crystal molecules in the liquid crystal layer, and thin film transistors (TFTs) that switch electrical signals supplied to the pixel electrodes. Known methods for driving liquid crystal molecules include vertical electric field methods such as the TN (Twisted Nematic) method and the VA (Vertical Alignment) method, and horizontal electric field methods such as the IPS (In-Plane Switching) method and the FFS (Fringe Field Switching) method. The horizontal electric field method, in which electrodes are formed on only one side of the substrate and an electric field is applied parallel to the substrate, is known as a liquid crystal display element that has a wider viewing angle and is capable of high-quality display compared to the conventional vertical electric field method, in which voltage is applied to electrodes formed on the top and bottom substrates to drive the liquid crystal.

[0003] As a liquid crystal aligning agent for a lateral electric field type liquid crystal display element, Patent Document 1 discloses a liquid crystal aligning agent containing a polymer obtained using a diamine component containing a diamine whose terminal amino group is alkylated.

[0004] WO2008-078796 publication

[0005] In IPS-mode liquid crystal display elements, static electricity easily accumulates in the liquid crystal cells. Furthermore, the application of asymmetric positive and negative voltages during operation can also cause charge accumulation in the liquid crystal cells. These accumulated charges can disrupt the liquid crystal alignment and cause image retention, significantly reducing the display quality of the liquid crystal display element. Furthermore, because charge accumulates when the liquid crystal cell is irradiated with backlight light immediately after operation, image retention can occur even after a short period of operation, and problems such as flickering can occur during operation.

[0006] In recent high-brightness liquid crystal display devices, the backlight brightness has become higher, and the visibility of afterimages due to accumulated charge has also increased, so liquid crystal alignment films that can reduce the absolute value of accumulated charge while quickly reducing the generated charge are required.In addition, there is a greater need than ever for liquid crystal alignment films that can reduce charge accumulation and flicker caused by backlight light.

[0007] In view of the above circumstances, the object of the present invention is to provide a liquid crystal alignment film that can reduce the absolute value of accumulated charge while reducing the generated charge in a short period of time, and a liquid crystal alignment agent that can obtain a liquid crystal alignment film in which charge accumulation and flicker caused by backlight light are reduced.

[0008] The present inventors have conducted extensive research to achieve the above object, and have found that the use of a polymer having a specific partial structure is effective for achieving the above object. They have also found that a liquid crystal aligning agent having the following constitution is optimal for achieving the above object, and have completed the present invention.

[0009] Thus, the present invention is based on the above findings and has the following gist: A liquid crystal aligning agent, comprising at least one polymer (P0) selected from the group consisting of a polyimide precursor having a partial structure (a0) represented by the following formula (0) and a polyimide which is an imidized product of the polyimide precursor: (In the formula, ** represents a bond to a saturated hydrocarbon group. ３ represents a branched alkyl group having 3 to 6 carbon atoms, or *-A ４ -Y ２ Represents. A ４represents an alkylene group having 1 to 6 carbon atoms; Y ２ represents an aromatic group, and * represents a bond. ２ Any hydrogen atom of the aromatic group in may be replaced with a monovalent group. X represents an (n+2)-valent aromatic group. Ｄ represents a hydrogen atom or a protecting group which is substituted with a hydrogen atom by heat, R Ｄ If there are multiple R Ｄ may be the same or different. n is an integer of 1 to 8.) Throughout this specification, examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, and * represents a bond. In the present invention, the main chain of a polymer refers to the "trunk" portion of the polymer, which is the longest chain of atoms. It is permissible for this "trunk" portion to contain a ring structure. Furthermore, the side chain of a polymer refers to the portion branching from the "trunk" of the polymer.

[0010] By using the liquid crystal aligning agent of the present invention, a liquid crystal alignment film can be obtained that can reduce the absolute value of accumulated charge while reducing generated charge in a short period of time, as well as a liquid crystal alignment film in which charge accumulation and flicker caused by backlight are reduced. The mechanism by which the above-mentioned effects of the present invention are achieved is not entirely clear, but the following is thought to be one of the reasons. During the baking process in the production of liquid crystal display elements, polyamic acid, the main component of the liquid crystal aligning agent, undergoes a thermal imidization reaction. The formation of imide rings not only makes it easier to absorb light, but also makes it less polar, making it difficult to reduce accumulated charge. It is thought that the above-mentioned effects are achieved because the imidization reaction is inhibited in the liquid crystal aligning agent containing the polymer having a specific partial structure of the present invention, even after the baking process, suppressing light absorption and making it more polar.

[0011] 1 is a schematic cross-sectional view showing an example of a horizontal electric field liquid crystal display element of the present invention, and FIG. 2 is a schematic cross-sectional view showing another example of a horizontal electric field liquid crystal display element of the present invention.

[0012] <Polymer (P0)> One embodiment of the polymer contained in the liquid crystal aligning agent of the present invention is at least one polymer (P0) selected from the group consisting of polyimide precursors having a partial structure (a0) represented by the above formula (0) and polyimides which are imidized products of the polyimide precursors. Note that the polymer (P0) may have the partial structure (a0) in the main chain of the polymer (P0) or in the side chain of the polymer (P0). (In the formula, ** represents a bond to a saturated hydrocarbon group. ３ represents a branched alkyl group having 3 to 6 carbon atoms, or *-A ４ -Y ２ Represents. A ４ represents an alkylene group having 1 to 6 carbon atoms; Y ２ represents an aromatic group, and * represents a bond. ２ Any hydrogen atom of the aromatic group in may be replaced with a monovalent group. X represents an (n+2)-valent aromatic group. Ｄ represents a hydrogen atom or a protecting group which is substituted with a hydrogen atom by heat, R Ｄ If there are multiple R Ｄ may be the same or different, and n is an integer of 1 to 8.

[0013] The polymer (P0) is also a polymer represented by the formula (2) described below, ２ In this case, **, which is a bond of the partial structure (a0), bonds to the saturated hydrocarbon group.

[0014] In the formula (0), X represents an aromatic group having a valence of (n+2). Specific examples of the aromatic group include the aromatic groups *-A ４ -Y ２ Y ２ Specific examples of the aromatic group in the formula (0) include (n+2)-valent aromatic groups obtained by removing (n+1) hydrogen atoms from the aromatic group in the formula (0). ３ is A in formula (2) described later. ３ is synonymous with.

[0015] -COOR in the above formula (0) Ｄ R inＤ represents a hydrogen atom or a protecting group that is replaced with a hydrogen atom by heat. The protecting group is preferably a protecting group that is removed by heat at 80°C or higher, and more preferably a protecting group that is removed by heat at 100°C or higher. Furthermore, from the viewpoint of suitably achieving the effects of the present invention, a protecting group that is removed by heat at 300°C or lower is preferred, a protecting group that is removed by heat at 250°C or lower is more preferred, and a protecting group that is removed by heat at 200°C or lower is even more preferred. Specific preferred examples of the protecting group that is replaced with a hydrogen atom by heat include structures selected from the group consisting of the following formulas (a-1) to (a-6): (In formula (a-2), R １ represents an alkyl group having 1 to 5 carbon atoms. * represents a bond.) <Polymer (P)> Another embodiment of the polymer contained in the liquid crystal aligning agent of the present invention is at least one polymer (P) selected from the group consisting of a polyimide precursor obtained using a tetracarboxylic acid component containing a tetracarboxylic acid dianhydride represented by the following formula (1) (also referred to as a specific aromatic tetracarboxylic acid component (p) in the present invention) and a diamine component containing a diamine represented by the following formula (2) (also referred to as a specific diamine (p) in the present invention), and a polyimide which is an imidized product of the polyimide precursor. The polymer (P) contained in the liquid crystal aligning agent of the present invention may be one type or two or more types. Here, the polyimide precursor is a polymer from which a polyimide can be obtained by imidizing a polyamic acid, a polyamic acid ester, or the like. (X ａ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride or a derivative thereof. ２ represents a divalent organic group having 2 to 42 carbon atoms and a saturated hydrocarbon group. ２ At least one of the amino groups bonded to X ２ A bonds to the saturated hydrocarbon group of ３ are each independently a branched alkyl group having 3 to 6 carbon atoms, or *-A ４ -Y ２ and * represents a bond. ４ represents an alkylene group having 1 to 6 carbon atoms; Y ２ represents an aromatic group. ２Any hydrogen atom of the aromatic group in may be replaced with a monovalent group.

[0016] (Tetracarboxylic Acid Component) The polyamic acid (P'), which is a polyimide precursor of the polymer (P), can be obtained, for example, by a polymerization reaction between a diamine component containing the specific diamine (p) and a tetracarboxylic dianhydride represented by the formula (1). When producing the polymer (P), the tetracarboxylic acid component to be reacted with the diamine component may be not only a tetracarboxylic acid dianhydride, but also a derivative of a tetracarboxylic acid dianhydride such as a tetracarboxylic acid, a tetracarboxylic acid dihalide, a tetracarboxylic acid dialkyl ester, or a tetracarboxylic acid dialkyl ester dihalide.

[0017] X in the above formula (1) ａ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride or a derivative thereof. The aromatic tetracarboxylic dianhydride is an acid dianhydride obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an aromatic ring. However, it is not necessary for the aromatic ring structure to be composed solely of an aromatic ring structure, and it may also have a chain hydrocarbon structure or an alicyclic structure in part. X in the above formula (1) ａ is preferably a structure selected from the following formulae (Xa-1) and (Xa-2):

[0018] (In formulas (Xa-1) to (Xa-2), j and k are integers of 0 or 1, and A １ and A ２ are each independently a single bond, —O—, —C(═O)—, —O—C(═O)—, a phenylene group, or —S(═O) ２ - or -NR-C(=O)- (R represents a hydrogen atom or a methyl group). ２ may be the same or different. * represents a bond.)

[0019] Preferred specific examples of the above formulae (Xa-1) and (Xa-2) include the following formulae (Xa-3) to (Xa-18). (* represents a bond.)

[0020] X ａ From the viewpoint of enhancing the liquid crystal alignment property, the above formulae (Xa-3) to (Xa-7) are more preferable, and the above formulae (Xa-3) to (Xa-6) are even more preferable.

[0021] The proportion of the specific aromatic tetracarboxylic acid component (p) used is preferably 10 mol % or more, more preferably 20 mol % or more, and even more preferably 50 mol % or more, based on 1 mol of all tetracarboxylic acid components used in the polymer (P).

[0022] The tetracarboxylic acid component used in the production of the polymer (P) may contain a tetracarboxylic acid component other than the specific aromatic tetracarboxylic acid component (p) (hereinafter also referred to as other tetracarboxylic acid component).

[0023] When other tetracarboxylic acid components are used in combination with the specific aromatic tetracarboxylic acid component (p), the amount of the specific aromatic tetracarboxylic acid component (p) used is preferably 90 mol % or less, more preferably 80 mol % or less, based on 1 mol of the total tetracarboxylic acid components used in the polymer (P).

[0024] Examples of the other tetracarboxylic acid component include acyclic aliphatic tetracarboxylic acid dianhydrides, alicyclic tetracarboxylic acid dianhydrides, and derivatives thereof. Here, the acyclic aliphatic tetracarboxylic acid dianhydrides are acid dianhydrides obtained by intramolecular dehydration of four carboxy groups bonded to a chain hydrocarbon structure. However, they do not necessarily have to be composed of chain hydrocarbon structures alone, and may also have an alicyclic structure or an aromatic ring structure as part of them.

[0025] Alicyclic tetracarboxylic acid dianhydrides are acid dianhydrides obtained by intramolecular dehydration of four carboxy groups, including at least one carboxy group bonded to an alicyclic structure. However, none of these four carboxy groups are bonded to an aromatic ring. Furthermore, they do not necessarily have to be composed solely of an alicyclic structure, and may partially contain a chain hydrocarbon structure or an aromatic ring structure.

[0026] The acyclic aliphatic or alicyclic tetracarboxylic acid dianhydride or a derivative thereof is preferably a tetracarboxylic acid dianhydride having at least one partial structure selected from the group consisting of a cyclobutane ring structure, a cyclopentane ring structure, and a cyclohexane ring structure, from the viewpoint of enhancing the liquid crystal alignment property.

[0027] The other tetracarboxylic acid component is preferably a tetracarboxylic acid dianhydride represented by the following formula (t) or a derivative thereof.

[0028] X in formula (t) Ｔ is a structure selected from the following formulas (X1-1) to (X1-23).

[0029]

[0030]

[0031]

[0032] In formulae (X1-1) to (X1-4), R １ ~R ２１ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group. １ ~R ２１ are each independently preferably a hydrogen atom, a halogen atom, a methyl group, or an ethyl group, and more preferably a hydrogen atom or a methyl group.

[0033] Specific examples of formula (X1-1) include the following formulae (1-1) to (1-6): From the viewpoint of enhancing the liquid crystal alignment property, formulae (1-1) to (1-2) are particularly preferred.

[0034] From the viewpoint of enhancing the liquid crystal alignment property, the X Ｔis preferably the above formula (X1-1) to (X1-10), or (X1-18) to (X1-23), more preferably the above formula (X1-1), (X1-5), (X1-7) to (X1-10), (X1-21), or (X1-23), and even more preferably the above formula (1-1), (1-2), (X1-5), (X1-7), (X1-8), or (X1-9).

[0035] Specific examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-biphenylsulfonetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3',4,4'-biphenylethertetracarboxylic dianhydride, 3,3',4,4'-perfluoroisopropylidenediphthalic dianhydride, and 3,3',4,4'-biphenyltetracarboxylic dianhydride. aromatic tetracarboxylic acid dianhydrides such as 2,2',3,3'-biphenyltetracarboxylic acid dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, ethylene glycol bisanhydrotrimate, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 4,4'-carbonyldiphthalic anhydride, 4,4'-oxydi(1,4-phenylene)bis(phthalic acid) dianhydride, and 4,4'-methylenedi(1,4-phenylene)bis(phthalic acid) dianhydride, or derivatives thereof.

[0036] (Specific diamine (p)) The specific diamine (p) of the present invention is a diamine represented by the above formula (2). The specific diamine (p) may be used singly or in combination of two or more. The amount of the specific diamine (p) used is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, relative to 1 mol of the diamine component used in the production of the polymer (P).

[0037] X in the above formula (2) ２ represents a divalent organic group having 2 to 42 carbon atoms and a saturated hydrocarbon group. ２ At least one of the amino groups bonded to X２ The divalent organic group preferably has 2 to 30 carbon atoms, and more preferably has 2 to 24 carbon atoms.

[0038] X in the above formula (2) ２ may be composed of only a chain hydrocarbon structure, or may have one or more ring structures such as an alicyclic structure or an aromatic ring structure, but preferably has one or more ring structures, and more preferably has one or more aromatic ring structures. In addition, the ring structure may be a nitrogen atom-containing structure containing a nitrogen atom.

[0039] X in the above formula (2) ２ is preferably a structure represented by the following formula (3), where the number of carbon atoms in the structure represented by formula (3) is 2 or more. ２ -(Y ３ -Z ３ ) ｎ - * (3) (Y ３ represents a divalent organic group having 6 to 30 carbon atoms and containing one or more ring structures. ２ , Z ３ each independently represents a divalent linear saturated hydrocarbon group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 4 to 6 carbon atoms, and n is an integer of 0 to 1. ３ Any hydrogen atom in the ring structure in may be replaced with a monovalent group. * represents a bond.

[0040] Y ３Examples of the ring structure contained in include an alicyclic structure and an aromatic ring structure, with an aromatic ring structure being preferred. The aromatic ring refers to an aromatic hydrocarbon or aromatic heterocycle, and includes monocyclic rings, fused rings, and rings in which monocyclic or fused rings are linked. Examples of the aromatic ring include a benzene ring, a naphthalene ring, and a biphenyl structure. Any hydrogen atom in the aromatic group may be replaced with a monovalent group. Examples of the monovalent group include a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, a fluoroalkenyl group having 2 to 10 carbon atoms, a fluoroalkoxy group having 1 to 10 carbon atoms, a carboxy group, a hydroxy group, an alkyloxycarbonyl group having 1 to 10 carbon atoms, a cyano group, and a nitro group.

[0041] Examples of the alicyclic structure include cyclopentane, cyclohexane, cycloheptane, cyclooctane, norbornane, and adamantane. ３ Is Z ２ , and / or Z ３ The polymer (P) is preferably bonded to Y through an atom constituting the ring structure, and more preferably bonded to Y through a carbon atom constituting the ring structure. ３ It is more preferable that the polymer (P) has a ring structure represented by Y in the main chain direction. ３ The phrase "having a ring structure represented by Y in the main chain direction of the polymer (P)" means that ３ This means that the ring structure contained in the group constitutes the main chain of the polymer (P).

[0042] When Y3 has two or more ring structures, the rings in the ring structures may be bonded to each other via a linking group. Examples of the linking group include a single bond, —CH ２ -, -C(CH ３ ) ２ -, -O-, -C(=O)-, -O-C(=O)-, -NR-C(=O)-, -NR- (R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a phenyl group, or a tert-butoxycarbonyl group), an alkylene group having 2 to 18 carbon atoms, or -CH of the alkylene group. ２ Part of - is -O-, -Si(CH３ ) ２ and divalent organic groups substituted with -, -C(=O)-, -O-C(=O)-, -NR-C(=O)-, or -NR- (R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a phenyl group, or a tert-butoxycarbonyl group).

[0043] Y ３ From the viewpoint of suitably obtaining the effects of the present invention, it is preferable that the compound has a structure represented by the following formula (4): (L is -CH ２ -, -O-, -C(=O)-, -N(R)- (wherein R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), a cyclohexylene group, or an alkylene group having 2 to 18 carbon atoms. However, any -CH ２ The - may be substituted with -O-, -O-C(=O)-, -C(=O)-, -N(R)- (wherein R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -N(R)-C(=O)- (wherein R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), a cyclohexylene group, or a phenylene group. Any hydrogen atom on the cyclohexylene group or phenylene group may be substituted with a halogen atom, or an alkyl or alkoxy group having 1 to 5 carbon atoms. C4 represents an aromatic group, an alicyclic hydrocarbon group, or an alicyclic hydrocarbon group containing a nitrogen atom selected from a piperidinediyl group and a piperazinediyl group. When multiple C4s are present, they may be the same or different. The piperidinediyl group is preferably a piperidine-1,4-diyl group, and the piperazinediyl group is preferably a piperazine-1,4-diyl group. R ４ represents a halogen atom, or an alkyl or alkoxy group having 1 to 5 carbon atoms, and any hydrogen atom of the alkyl or alkoxy group may be substituted with a halogen atom, and any hydrocarbon group may be substituted with an amino group protected with a tert-butoxycarbonyl group. Multiple a's are each independently an integer of 0 to 4, b is an integer of 1 to 3, and b is preferably an integer of 1 to 2, and c is an integer of 0 to 1. b+c is preferably an integer of 1 to 3. R ４When a plurality of a's are present, they may be the same or different.

[0044] More preferred specific examples of L include -O-, -O-C(=O)-, -C(=O)-, -N(R)- (R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -N(R)-C(=O)- (R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -N(R)-C(=O)-N(R)- (R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group; two Rs may be the same or different), -(CH ２ ) ｐ -, -O-(CH ２ ) ｐ -O-, -(CH ２ ) ｐ -OC(=O)-(CH ２ ) ｑ -, -(CH ２ ) ｐ -N(R)-(CH ２ ) ｑ -(R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -(CH ２ ) ｐ -N(R)-C(=O)-N(R)-(CH ２ ) ｑ -(R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group. Two R may be the same or different.), -O-(CH ２ ) ｐ -O-(CH ２ ) ｑ -O-, -(CH ２ ) ｐ’ -OC(=O)-(CH ２ ) ｑ -C(=O)-O-(CH ２ ) ｒ’ -, -(CH ２ ) ｐ’ -C(=O)-O-(CH ２ ) ｑ -OC(=O)-(CH ２ ) ｒ’ -, -(CH ２ ) ｐ’-OC(=O)-Q-C(=O)-O-(CH ２ ) ｑ’ -(Q represents a phenylene group or a cyclohexylene group), -(CH ２ ) ｐ’ -C(=O)-O-Q-OC(=O)-(CH ２ ) ｑ’ - (Q represents a phenylene group or a cyclohexylene group). Here, p represents an integer of 1 to 6, preferably an integer of 2 to 6. q represents an integer of 1 to 6, more preferably an integer of 2 to 6, and even more preferably an integer of 2 to 4. p', q', and r' each independently represent an integer of 0 to 6. In addition, the relationships 0≦p'+q'≦10 and 2≦p'+q+r'≦16 are satisfied.

[0045] Z in the above formula (3) ２ , Z ３ are each independently a divalent, linear, saturated hydrocarbon group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 4 to 6 carbon atoms. The divalent, linear, saturated hydrocarbon group having 1 to 6 carbon atoms may be linear or branched. From the viewpoint of improving liquid crystal alignment, a linear alkylene group is preferred, and a methylene group or an ethylene group is more preferred.

[0046] A in the above formula (2) ３ are each independently a branched alkyl group having 3 to 6 carbon atoms, or *-A ４ -Y ２ *-A ４ -Y ２ A in ４ is an alkylene group having 1 to 6 carbon atoms. ４ is preferably a methylene group or an ethylene group. ４ -Y ２ Y in ２ represents an aromatic group, and * represents a bond.

[0047] Y ２ From the viewpoint of suitably obtaining the effects of the present invention, Y is preferably a monovalent aromatic group having 4 to 30 carbon atoms. ２The aromatic group in the above refers to an aromatic hydrocarbon group or an aromatic heterocyclic group, and includes monocyclic groups, fused ring groups, and groups in which monocyclic or fused rings are linked. Any hydrogen atom in the aromatic group may be replaced with a monovalent group. Examples of the monovalent group include a halogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, a fluoroalkenyl group having 2 to 10 carbon atoms, a fluoroalkoxy group having 1 to 10 carbon atoms, a carboxy group, a hydroxy group, an alkyloxycarbonyl group having 1 to 10 carbon atoms, a cyano group, and a nitro group.

[0048] Y ２ Examples of the aromatic ring structure in the aromatic group include aromatic hydrocarbon rings such as a benzene ring, a naphthalene ring, and a biphenyl structure; 5-membered aromatic heterocycles such as a pyrrole ring, a furan ring, a thiophene ring, an imidazole ring, a pyrazole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, and a triazole ring; 6-membered aromatic heterocycles such as a pyridine ring, a pyrimidine ring, a pyridazine ring, a triazine ring, and a pyrazine ring; and polycyclic aromatic heterocycles such as an indole ring, a benzimidazole ring, a purine ring, a quinoline ring, an isoquinoline ring, a naphthyridine ring, a quinoxaline ring, a phthalazine ring, a carbazole ring, and an acridine ring.

[0049] More preferred specific examples of the diamine represented by the formula (2) include those represented by the following formula (D Ａ -1) to (D Ａ The diamines represented by the following formula (D-24) are also suitable. Ａ -1) to (D Ａ In formula (D-24), m is an integer of 0 to 6, and m1, m2, n1, and n2 are each an integer of 1 to 6. Ａ -1) to (D Ａ The hydrogen atom on the benzene ring in -24) may be substituted with a monovalent substituent.

[0050] The diamine component used in the production of the polymer (P) may contain a diamine other than the specific diamine (p) (hereinafter also referred to as "other diamine"). When other diamines are used in addition to the specific diamine (p), the amount of the specific diamine (p) used relative to 1 mole of the diamine component used in the production of the polymer (P) is preferably 90 mol% or less, more preferably 80 mol% or less.

[0051] Examples of other diamines include, but are not limited to, the following. The above other diamines may be used singly or in combination of two or more: p-phenylenediamine, m-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-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, 3,4'-diaminobiphenyl, 4,4'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, ＡＬ -1) to (d ＡＬdiamines represented by the formula (I-12), 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)undecane, 1,11-bis(3-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)undecane, 1,12-bis(4-aminophenoxy)dodecane, 1,12-bis(3-aminophenoxy)dodecane, 1,2-bis(6-amino-2-naphthyloxy)ethane, 1,2-bis(6-amino-2-naphthyl)ethane, 6-[2-(4-aminophenoxy)ethoxy]-2-naphthylamine, 1,4-phenylenebis(4-aminobenzoate), 1,4-phenylenebis(3-aminobenzoate), 1,3-phenylenebis(4-aminobenzoate), 1,3-phenylenebis(3-aminobenzoate) bis(4-aminophenyl)terephthalate, bis(3-aminophenyl)terephthalate, bis(4-aminophenyl)isophthalate, bis(3-aminophenyl)isophthalate, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 4-(2-(methylamino)ethyl)aniline, 4-(2-aminoethyl)aniline, 4,4'-diaminobenzophenone, 1,4-bis(4-aminophenyl)benzene, 1,3-bis(4-aminophenyl)benzene benzene, 1,4-bis(4-aminobenzyl)benzene, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy)diphenyl ether, 1,4-bis[4-(4-aminophenoxy)phenoxy]benzene (hereinafter, these are also collectively referred to as first diamines).diamines having a photoalignment group such as 4,4'-diaminoazobenzene or diaminotolane; diamines having an amide bond such as 4,4'-diaminobenzanilide; diamines having a urea bond such as 1,3-bis(4-aminophenyl)urea, 1,3-bis(4-aminobenzyl)urea, and 1,3-bis(4-aminophenethyl)urea; 2,6-diaminopyridine, 3,4-diaminopyridine, and 2,4-diaminopyrimidinyl 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N-(3-(1H-imidazol-1-yl)propyl-3,5-diaminobenzamide, 4-[4-[(4-aminophenoxy)methyl]-4,5-dihydro-4 heterocycle-containing diamines such as N,N'-methyl-2-oxazolyl]-benzeneamine, or diamines represented by the following formulae (z-1) to (z-13), or diamines having at least one nitrogen atom-containing structure selected from the group consisting of a nitrogen atom-containing heterocycle, a secondary amino group, and a tertiary amino group (hereinafter also referred to as a specific nitrogen atom-containing structure), typified by diamines having a diphenylamine structure such as 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenyl-N-methylamine, 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-benzenediamine (provided that the molecule does not have an amino group bonded to a protecting group that is cleaved by heating and replaced with a hydrogen atom; and the specific diamine (p) is excluded).), 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol; 4,4'-diamino-3,3'-dihydroxybiphenyl; 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 1,2-bis(4-aminophenyl)ethane-3-carboxylic acid, 4, Diamines having a carboxy group such as 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, and 4,4'-diaminodiphenylether-3,3'-dicarboxylic acid; 4-(2-(methylamino )ethyl)aniline, 4-(2-aminoethyl)aniline, 1-(4-aminophenyl)-1,3,3-trimethyl-1H-indan-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine; diamines having a photopolymerizable group at the terminal such as 2-(2,4-diaminophenoxy)ethyl methacrylate and 2,4-diamino-N,N-diallylaniline; cholestanyloxy-3,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene diamines having a steroid skeleton such as cholestanyloxy-2,4-diaminobenzene, cholestanyl 3,5-diaminobenzoate, cholestanyl 3,5-diaminobenzoate, lanostannyl 3,5-diaminobenzoate, and 3,6-bis(4-aminobenzoyloxy)cholestane; diamines represented by the following formulae (V-1) to (V-2); and groups "-N(D)-" such as those represented by the following formulae (5-1) to (5-8) (D represents a protecting group which is eliminated by heating and replaced with a hydrogen atom, and is preferably a tert-butoxycarbonyl group).diamines having a siloxane bond such as 1,3-bis(3-aminopropyl)-tetramethyldisiloxane; metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), and diamines in which two amino groups are bonded to a group represented by any one of formulas (Y-1) to (Y-167) described in WO2018 / 117239.

[0052]

[0053] In the formula (V-1), m and n each independently represent an integer of 0 to 3, and satisfy the relationship 1≦m+n≦4. j represents an integer of 0 or 1. X １ is -(CH ２ ) ａ -(a is an integer of 1 to 15), -CONH-, -NHCO-, -CO-N(CH ３ )-, -NH-, -O-, -CH ２ O-, -CH ２ represents —OCO—, —COO—, or —OCO—. １ represents a monovalent group such as a fluorine atom, a fluorine atom-containing alkyl group having 1 to 10 carbon atoms, a fluorine atom-containing alkoxy group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkoxyalkyl group having 2 to 10 carbon atoms. ２ is -O-, -CH ２ O-, -CH ２ m, n, and X represent —OCO—, —COO—, or —OCO—. １ , R １ When two occur, each independently has the above definition.

[0054] (Boc represents a tert-butoxycarbonyl group.)

[0055] Examples of the nitrogen atom-containing heterocycle that the diamine having a nitrogen atom-containing structure may have include pyrrole, imidazole, pyrazole, triazole, pyridine, pyrimidine, pyridazine, pyrazine, indole, benzimidazole, purine, quinoline, isoquinoline, naphthyridine, quinoxaline, phthalazine, triazine, carbazole, acridine, piperidine, piperazine, pyrrolidine, and hexamethyleneimine. Among these, pyridine, pyrimidine, pyrazine, piperidine, piperazine, quinoline, carbazole, and acridine are preferred.

[0056] From the viewpoint of enhancing liquid crystal alignment properties, the other diamine may be a diamine selected from the group consisting of the first diamine, a diamine having an amide bond, a diamine having a urea bond, a diamine having a group "-N(D)-", a diamine having a specific nitrogen atom-containing structure, and a diamine having a carboxy group.

[0057] (Liquid Crystal Aligning Agent) The liquid crystal aligning agent of the present invention is a liquid composition obtained by dispersing or dissolving the polymer (P) and other components used as needed, preferably in a suitable solvent.

[0058] The liquid crystal aligning agent of the present invention may contain other polymers other than the polymer (P). Specific examples of other polymers include, in addition to the polymer (P), at least one polymer selected from the group consisting of a polyimide precursor obtained using a diamine component not containing the specific diamine (p) and a polyimide which is an imidized product of the polyimide precursor (also referred to as polymer (B) in the present invention), polysiloxane, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-maleic anhydride) copolymer, poly(isobutylene-maleic anhydride) copolymer, poly(vinyl ether-maleic anhydride) copolymer, poly(styrene-phenylmaleimide) derivative, and a polymer selected from the group consisting of poly(meth)acrylate.

[0059] Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, SMA2000, and SMA3000 (manufactured by Cray Valley Corporation), and GSM301 (manufactured by Gifu Ceramics Manufacturing Co., Ltd.), while a specific example of poly(isobutylene-maleic anhydride) copolymers includes ISOBAM-600 (manufactured by Kuraray Co., Ltd.). A specific example of poly(vinyl ether-maleic anhydride) copolymers includes Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by Ashland). Among these, polymer (B) is more preferred from the viewpoint of improving the display quality of liquid crystal display elements. The other polymers may be used alone or in combination of two or more. The content of the other polymers is preferably 90 parts by mass or less, more preferably 10 to 90 parts by mass, and even more preferably 20 to 80 parts by mass, relative to 100 parts by mass of the total polymers contained in the liquid crystal aligning agent.

[0060] (Polymer (B)) Specific examples of the tetracarboxylic acid component used in the production of the polymer (B) include the same compounds as those exemplified for the polymer (P), including preferred specific examples. The tetracarboxylic acid component used in the production of the polymer (B) more preferably contains a tetracarboxylic acid dianhydride or a derivative thereof having at least one partial structure selected from the group consisting of a benzene ring, a cyclobutane ring, a cyclopentane ring, and a cyclohexane ring (hereinafter, these may be referred to as specific tetracarboxylic acid component (B)). The amount of the specific tetracarboxylic acid component (B) used is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 50 mol% or more, based on 1 mol of the total tetracarboxylic acid components used in the production of the polymer (B).

[0061] Examples of diamine components for obtaining polymer (B) include the diamines exemplified for polymer (P) above. Among these, at least one diamine selected from the group consisting of the first diamine, a diamine having a urea bond, a diamine having an amide bond, and a diamine having an "-N(D)-" group (also referred to as specific diamine (b) in the present invention) is preferably included. The diamine component may be a single diamine or a combination of two or more diamines. When specific diamine (b) is used, its amount is preferably 10 mol % or more, more preferably 20 mol % or more, of the total diamine components used in the production of polymer (B). When a diamine other than specific diamine (b) is used, the amount of specific diamine (b) is preferably 90 mol % or less, more preferably 80 mol % or less, based on 1 mole of the total diamine components used in the production of polymer (B).

[0062] (Production of Polyamic Acid) Polyamic acid is produced by reacting a diamine component and a tetracarboxylic acid component in an organic solvent. The ratio of the tetracarboxylic acid component and the diamine component used in the polyamic acid production reaction is preferably such that 1 equivalent of the amino group of the diamine component corresponds to 0.5 to 2 equivalents of the acid anhydride group of the tetracarboxylic acid component, more preferably 0.8 to 1.2 equivalents. As with a typical polycondensation reaction, the closer the equivalent of the acid anhydride group of the tetracarboxylic acid component is to 1 equivalent, the higher the molecular weight of the resulting polyamic acid. The reaction temperature in the production of polyamic acid is preferably −20 to 150°C, more preferably 0 to 100°C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours. Polyamic acid can be produced at any concentration, but the polyamic acid concentration is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The reaction can be carried out at a high concentration initially, with subsequent addition of solvent.

[0063] Specific examples of the organic solvent include cyclohexanone, cyclopentanone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide (hereinafter also referred to as DMAc), dimethyl sulfoxide, and 1,3-dimethyl-2-imidazolidinone. Furthermore, when the polymer has high solvent solubility, solvents such as methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, and diethylene glycol monoethyl ether can be used.

[0064] (Production of Polyamic Acid Ester) The polyamic acid ester can be obtained by known methods such as [I] a method of reacting the polyamic acid obtained by the above method with an esterifying agent, [II] a method of reacting a tetracarboxylic acid diester with a diamine, or [III] a method of reacting a tetracarboxylic acid diester dihalide with a diamine.

[0065] (Production of Polyimide) Polyimide can be obtained by ring-closing (imidizing) a polyimide precursor such as the polyamic acid or polyamic acid ester. The imidization ratio in this specification refers to the ratio of imide groups to the total amount of imide groups derived from tetracarboxylic dianhydride or its derivatives and carboxyl groups (or their derivatives). The imidization ratio does not necessarily have to be 100% and can be adjusted as desired depending on the application and purpose.

[0066] Methods for imidizing the polyimide precursor include thermal imidization, in which a solution of the polyimide precursor is heated as is, and catalytic imidization, in which a catalyst is added to a solution of the polyimide precursor. When thermally imidizing the polyimide precursor in solution, the temperature is preferably 100 to 400°C, more preferably 120 to 250°C, and it is preferable to carry out the thermal imidization while removing water produced by the imidization reaction from the system.

[0067] Catalytic imidization of polyimide precursors can be carried out by adding a basic catalyst and an acid anhydride to a solution of the polyimide precursor and stirring the mixture at preferably -20 to 250°C, more preferably 0 to 180°C. The amount of the basic catalyst is preferably 0.5 to 30 times, more preferably 2 to 20 times, the molar ratio of the amic acid groups, and the amount of the acid anhydride is preferably 1 to 50 times, more preferably 3 to 30 times, the molar ratio of the amic acid groups. Examples of basic catalysts include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Of these, pyridine is preferred because it has adequate basicity for promoting the reaction. Examples of acid anhydrides include acetic anhydride, trimellitic anhydride, and pyromellitic anhydride. Of these, acetic anhydride is preferred because it facilitates purification after the reaction. The imidization rate by catalytic imidization can be controlled by adjusting the catalyst amount, reaction temperature, and reaction time.

[0068] When recovering the produced polyimide precursor or polyimide from a reaction solution of a polyimide precursor or polyimide, the reaction solution may be precipitated by pouring the reaction solution into a solvent. Examples of solvents used for precipitation include methanol, ethanol, isopropyl alcohol (hereinafter also referred to as IPA), acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, toluene, benzene, and water. The polymer precipitated by pouring into the solvent can be recovered by filtration and then dried at room temperature or by heating under atmospheric or reduced pressure. Furthermore, the recovered polymer can be redissolved in an organic solvent and reprecipitated and recovered 2 to 10 times to reduce the amount of impurities in the polymer. Examples of solvents used in this process include alcohols, ketones, and hydrocarbons. Using three or more solvents selected from these solvents is preferred because it further increases the efficiency of purification.

[0069] When producing the polyimide precursor or polyimide of the present invention, a terminal-capped polymer may be produced using a tetracarboxylic acid component containing a tetracarboxylic dianhydride or a derivative thereof, a diamine component containing a diamine, and an appropriate terminal-capping agent. Terminal-capping polymers have the effect of improving the film hardness of the liquid crystal alignment film obtained by coating and improving the adhesion properties between the sealant and the liquid crystal alignment film. Examples of terminal groups of the polyimide precursor or polyimide of the present invention include amino groups, carboxy groups, acid anhydride groups, and groups derived from terminal-capping agents described below. The amino groups, carboxy groups, and acid anhydride groups can be obtained by a conventional condensation reaction or by terminal-capping with the following terminal-capping agents.

[0070] Examples of the end-capping agent include acid anhydrides such as acetic anhydride, maleic anhydride, nadic anhydride, phthalic anhydride, itaconic anhydride, 1,2-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, and 4-ethynylphthalic anhydride; dicarbonate diester compounds such as di-tert-butyl dicarbonate and diallyl dicarbonate; chlorocarbonyl compounds such as acryloyl chloride, methacryloyl chloride, and nicotinic acid chloride; Examples of the amino acid include 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, and n-octylamine; and isocyanates having an unsaturated bond such as ethyl isocyanate, phenyl isocyanate, naphthyl isocyanate, 2-acryloyloxyethyl isocyanate, and 2-methacryloyloxyethyl isocyanate.

[0071] The proportion of the end-capping agent used is preferably 0.01 to 20 parts by mole, and more preferably 0.01 to 10 parts by mole, per 100 parts by mole of the total of the diamine components used.

[0072] The polystyrene-equivalent weight average molecular weight (Mw) of the polyimide precursor and polyimide measured by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by GPC, is preferably 15 or less, more preferably 10 or less. By having the molecular weight within this range, good liquid crystal alignment properties can be ensured in liquid crystal display elements.

[0073] The organic solvent contained in the liquid crystal aligning agent according to the present invention is not particularly limited as long as it can uniformly dissolve the polymer (P) and other polymers added as needed. Examples of the organic solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactamide, N,N-diethylacetamide, N,N-dimethylpropionamide, tetramethylurea, N,N-diethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, γ-valerolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylacet ... Examples of suitable solvents include N-methyl-2-pyrrolidone, N-ethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, 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, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, and N-cyclohexyl-2-pyrrolidone (collectively referred to as "good solvents"). Among these, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, and γ-butyrolactone are preferred. The content of the good solvent is preferably 20 to 99% by mass, more preferably 20 to 90% by mass, and particularly preferably 30 to 80% by mass of the total solvent contained in the liquid crystal aligning agent.

[0074] Furthermore, the organic solvent contained in the liquid crystal aligning agent is preferably a mixed solvent containing, in addition to the above solvent, a solvent (also referred to as a poor solvent) that improves the coatability and surface smoothness of the coating film when the liquid crystal aligning agent is applied. Specific examples of poor solvents are listed below, but are not limited to these. The content of the poor solvent is preferably 1 to 80 mass %, more preferably 10 to 80 mass %, and particularly preferably 20 to 70 mass %, of the total solvent contained in the liquid crystal aligning agent. The type and content of the poor solvent are appropriately selected depending on the coater, coating conditions, coating environment, etc. of the liquid crystal aligning agent.

[0075] Examples of poor solvents include diisopropyl ether, diisobutyl ether, diisobutyl carbinol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-dibutoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, and 3-ethoxybutyl acetone. tartrate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene glycol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxyethoxy)-1- Propanol, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monopropyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol acetate, propylene glycol diacetate, Examples of suitable esters include n-butyl acetate, propylene glycol monoethyl ether acetate, cyclohexyl acetate, 4-methyl-2-pentyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl-4-heptanone), and (1S,5R)-6,8-dioxabicyclo[3.2.1]octan-4-one.

[0076] Of these, diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone is preferred.

[0077] Preferred solvent combinations of a good solvent and a poor solvent include N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone, and N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether. Coal diacetate, N,N-dimethyl lactamide and diisobutyl ketone, N-methyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-methyl-2-pyrrolidone, ethyl 3-ethoxypropionate and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, ethyl 3-ethoxypropionate and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, ethyl 3-ethoxypropionate and diethylene glycol mono propyl ether, N-ethyl-2-pyrrolidone, ethyl 3-ethoxypropionate, and diethylene glycol monopropyl ether, N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether acetate, N-ethyl-2-pyrrolidone and dipropylene glycol dimethyl ether, N,N-dimethyl lactamide and ethylene glycol monobutyl ether, N,N-dimethyl lactamide and propylene glycol diacetate, N-ethyl-2-pyrrolidone and diethylene glycol diethyl ether, N-ethyl-2 -pyrrolidone, diethylene glycol monoethyl ether, and butyl cellosolve acetate, N-methyl-2-pyrrolidone, diethylene glycol monomethyl ether, and butyl cellosolve acetate, N,N-dimethyl lactamide and diethylene glycol diethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone, and diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, and 4-hydroxy-4-methyl-2-pentanone,N-ethyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and diisobutyl ketone, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and dipropylene glycol monomethyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone, and dipropylene glycol monomethyl ether Methyl-2-pentanone and propylene glycol diacetate, N-ethyl-2-pyrrolidone, 4-hydroxy-4-methyl-2-pentanone and dipropylene glycol dimethyl ether, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diisobutyl ketone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and propylene glycol diacetate, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether and diisobutyl ketone, N-methyl-2-pi rolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisopropyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisobutylcarbinol, N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether, N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol pyrene glycol monomethyl ether, N-ethyl-2-pyrrolidone, diethylene glycol diethyl ether, and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and propylene glycol diacetate, N-ethyl-2-pyrrolidone, propylene glycol monobutyl ether, and diisobutyl ketone, N-ethyl-2-pyrrolidone, γ-butyrolactone, and diisobutyl ketone, N-ethyl-2-pyrrolidone, N,N-dimethyl lactamide, and diisobutyl ketone,Examples include N-methyl-2-pyrrolidone, ethylene glycol monobutyl ether, and ethylene glycol monobutyl ether acetate, γ-butyrolactone, ethylene glycol monobutyl ether acetate, and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone, ethylene glycol monobutyl ether acetate, and propylene glycol dimethyl ether, N-methyl-2-pyrrolidone, 4-methyl-2-pentyl acetate, and ethylene glycol monobutyl ether, N-ethyl-2-pyrrolidone, cyclohexyl acetate, and 4-hydroxy-4-methyl-2-pentanone, cyclohexanone, and propylene glycol monomethyl ether, cyclopentanone, and propylene glycol monomethyl ether, and N-methyl-2-pyrrolidone, cyclohexanone, and propylene glycol monomethyl ether.

[0078] (Liquid Crystal Aligning Agent) The liquid crystal aligning agent of the present invention contains the polymer (P) and, if necessary, the other polymers and the organic solvent. The total content of the polymers contained in the liquid crystal aligning agent of the present invention can be appropriately changed depending on the thickness of the coating film to be formed, but is preferably 1% by mass or more from the viewpoint of forming a uniform, defect-free coating film, and is preferably 10% by mass or less from the viewpoint of storage stability of the solution. A particularly preferred total polymer content is 2 to 8% by mass. The content of the polymer (P) used in the present invention is preferably 1 to 100% by mass, more preferably 10 to 100% by mass, and particularly preferably 20 to 100% by mass, based on the total polymers contained in the liquid crystal aligning agent.

[0079] The liquid crystal aligning agent of the present invention may contain, in addition to the polymer (P), the other polymer, and the organic solvent, other components (hereinafter also referred to as additive components). Examples of such additive components include at least one crosslinking compound selected from the group consisting of a crosslinking compound having at least one substituent selected from an oxiranyl group, an oxetanyl group, a blocked isocyanate group, an oxazoline group, a cyclocarbonate group, a hydroxy group, and an alkoxy group, and a crosslinking compound having a polymerizable unsaturated group, a functional silane compound, a metal chelate compound, a curing accelerator, a surfactant, an antioxidant, a sensitizer, a preservative, and a compound for adjusting the dielectric constant or electrical resistance of the resulting liquid crystal alignment film.

[0080] Specific preferred examples of the crosslinkable compound 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, glycerin diglycidyl ether, dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexaglycidyl ether, and bisphenol A type epoxy resins such as Epicoat (registered trademark) 828 (manufactured by Mitsubishi Chemical Corporation), bisphenol F type epoxy resins such as Epicoat 807 (manufactured by Mitsubishi Chemical Corporation), hydrogenated bisphenol A type epoxy resins such as YX-8000 (manufactured by Mitsubishi Chemical Corporation), biphenyl skeleton-containing epoxy resins such as YX6954BH30 (manufactured by Mitsubishi Chemical Corporation), phenol novolac type epoxy resins such as EPPN-201 (manufactured by Nippon Kayaku Co., Ltd.), (o, m, p-) cresol novolac type epoxy resins such as EOCN-102S (manufactured by Nippon Kayaku Co., Ltd.), resins, triglycidyl isocyanurates such as TEPIC (registered trademark) (manufactured by Nissan Chemical Industries, Ltd.), alicyclic epoxy resins such as CELLOXIDE (registered trademark) 2021P (manufactured by Daicel Corporation), compounds containing a tertiary nitrogen atom such as N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, or N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and compounds having two or more oxiranyl groups such as tetrakis(glycidyloxymethyl)methane. Compounds: compounds having two or more oxetanyl groups described in paragraphs

[0170] to

[0175] of WO 2011 / 132751; compounds having two or more oxetanyl groups, such as Coronate (registered trademark) AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Millionate (registered trademark) MS-50 (all manufactured by Tosoh Corporation), and Takenate (registered trademark) B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, and B-882N (all manufactured by Mitsui Chemicals, Inc.);Compounds having an oxazoline group such as 2,2'-bis(2-oxazoline), 2,2'-bis(4-methyl-2-oxazoline), 2,2'-bis(5-methyl-2-oxazoline), 1,2,4-tris(2-oxazolinyl)-benzene, and EPOCROS (registered trademark) (manufactured by Nippon Shokubai Co., Ltd.); compounds having a cyclocarbonate group described in paragraphs

[0025] to

[0030] and

[0032] of WO 2011 / 155577; N,N,N',N'-tetrakis(2-hydroxyethyl)adipamide, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethoxyphenyl)propane, 2,2-bis(4-hydroxy-3,5-di Examples of the crosslinkable compound include compounds having a hydroxy group or an alkoxy group, such as (hydroxymethylphenyl)-1,1,1,3,3,3-hexafluoropropane; and compounds represented by glycerin mono(meth)acrylate, glycerin di(meth)acrylate (1,2-,1,3-mixture), glycerin tris(meth)acrylate, glycerin 1,3-diglycerolate di(meth)acrylate, pentaerythritol tri(meth)acrylate, diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, tetraethylene glycol mono(meth)acrylate, pentaethylene glycol mono(meth)acrylate, and hexaethylene glycol mono(meth)acrylate. The content of the crosslinkable compound is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal alignment agent.

[0081] Examples of the compound for adjusting the dielectric constant or electrical resistance include monoamines having a nitrogen atom-containing aromatic heterocycle such as 3-picolylamine. The content of the monoamine having a nitrogen atom-containing aromatic heterocycle is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal aligning agent.

[0082] Specific preferred examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-glycidoxypropylmethyldimethoxysilane. Examples of the functional silane compound include 3-(2-methyl-2-methylpropyl)isocyanurate, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris(3-trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanatopropyltriethoxysilane. The content of the functional silane compound is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the polymer component contained in the liquid crystal alignment agent.

[0083] The solids concentration in the liquid crystal aligning agent (the ratio of the total mass of the components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected taking into consideration viscosity, volatility, etc., but is preferably 1 to 10% by mass. A particularly preferred range of solids concentration varies depending on the method used to apply the liquid crystal aligning agent to the substrate. For example, when using a spin coating method, a solids concentration of 1.5 to 4.5% by mass is particularly preferred. When using a printing method, a solids concentration of 3 to 9% by mass is particularly preferred, thereby resulting in a solution viscosity of 12 to 50 mPa·s. When using an inkjet method, a solids concentration of 1 to 5% by mass is particularly preferred, thereby resulting in a solution viscosity of 3 to 15 mPa·s. The temperature when preparing the polymer composition is preferably 10 to 50°C, more preferably 20 to 30°C.

[0084] <Liquid Crystal Alignment Film / Liquid Crystal Display Element> A liquid crystal alignment film can be produced by using the liquid crystal aligning agent. The liquid crystal display element of the present invention comprises the liquid crystal alignment film. The operation mode of the liquid crystal display element of the present invention is not particularly limited, and it can be applied to various operation modes, such as TN type, STN (Super Twisted Nematic) type, vertical alignment type (including VA-MVA type, VA-PVA type, etc.), IPS mode, FFS mode, and optically compensated bend mode (OCB type). The liquid crystal alignment film of the present invention is particularly suitable for horizontal alignment type liquid crystal display elements such as IPS mode or FFS mode.

[0085] The liquid crystal display element of the present invention can be produced, for example, by a method including the following steps (1) to (4), a method including steps (1) to (2) and (4), a method including steps (1) to (3), (4) and (5), or a method including steps (1) to (3), (4) and (6).

[0086] <Step (1): Step of Applying Liquid Crystal Alignment Agent to Substrate> Step (1) is a step of applying the liquid crystal aligning agent of the present invention to a substrate. Specific examples of step (1) are as follows. The liquid crystal aligning agent of the present invention is applied to one side of a substrate having a patterned transparent conductive film by an appropriate application method, such as a roll coater method, a spin coat method, a printing method, or an inkjet method. The substrate is not particularly limited as long as it is highly transparent. In addition to glass substrates and silicon nitride substrates, plastic substrates such as acrylic substrates and polycarbonate substrates can also be used. In addition, in reflective liquid crystal display elements, an opaque material such as a silicon wafer can be used for only one substrate. In this case, a light-reflecting material such as aluminum can also be used for the electrode. Furthermore, when manufacturing an IPS or FFS liquid crystal display element, a substrate having an electrode made of a comb-shaped patterned transparent conductive film or metal film and an opposing substrate having no electrode are used.

[0087] Examples of a method for applying the liquid crystal alignment agent to a substrate and forming a film include screen printing, offset printing, flexographic printing, an inkjet method, and a spray method. Among these, the application and film formation method by the inkjet method is preferably used.

[0088] <Step (2): Step of Baking the Applied Liquid Crystal Alignment Agent> Step (2) is a step of baking the liquid crystal alignment agent applied to the substrate to form a film. Specific examples of step (2) are as follows. After applying the liquid crystal alignment agent to the substrate in step (1), the solvent can be evaporated or the polyamic acid or polyamic acid ester can be thermally imidized using a heating means such as a hot plate, a hot air circulation oven, or an IR (infrared) oven. The drying and baking steps after applying the liquid crystal alignment agent of the present invention can be performed at any temperature and for any time, and may be performed multiple times. The temperature at which the solvent in the liquid crystal alignment agent is reduced can be, for example, 40 to 180°C. From the perspective of shortening the process, the baking can also be performed at 40 to 150°C. The baking time is not particularly limited, but may be 1 to 10 minutes or 1 to 5 minutes. When thermal imidization of polyamic acid or polyamic acid ester is carried out, a baking step may be added after the above step, for example, at a temperature range of 150 to 300°C or 150 to 250°C. The baking time is not particularly limited, but examples include baking times of 5 to 40 minutes or 5 to 30 minutes. If the film-like material after baking is too thin, the reliability of the liquid crystal display element may decrease, so the film thickness is preferably 5 to 300 nm, more preferably 10 to 200 nm.

[0089] <Step (3): Alignment Treatment of the Film Obtained in Step (2)> Step (3) is a step of optionally aligning the film obtained in Step (2). That is, in horizontal alignment type liquid crystal display devices such as IPS or FFS modes, the coating film is subjected to an alignment ability imparting treatment. On the other hand, in vertical alignment type liquid crystal display devices such as VA or PSA modes, the formed coating film can be used as a liquid crystal alignment film as is, or the coating film may be subjected to an alignment ability imparting treatment. Examples of alignment treatment methods for liquid crystal alignment films include rubbing treatment and photo-alignment treatment. Examples of photo-alignment treatment methods include irradiating the surface of the film with polarized radiation in a certain direction and, optionally, performing a heat treatment at a temperature preferably between 150 and 250°C to impart liquid crystal alignment (also referred to as liquid crystal alignment ability). The radiation can be ultraviolet light or visible light having a wavelength of 100 to 800 nm. Among these, ultraviolet light having a wavelength of 100 to 400 nm is preferred, and more preferably between 200 and 400 nm.

[0090] The rubbing treatment method includes rubbing the coating film in a certain direction with a roll wrapped with a cloth made of fibers such as nylon, rayon, or cotton. In the photo-alignment treatment method, when the radiation is polarized, it may be linearly polarized or partially polarized. Furthermore, when the radiation used is linearly polarized or partially polarized, irradiation may be performed from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these. When irradiating with unpolarized radiation, the irradiation direction is preferably oblique.

[0091] <Step (4): Step of preparing a liquid crystal cell> Two substrates on which a liquid crystal alignment film has been formed are prepared as described above, and a liquid crystal is placed between the two substrates arranged opposite each other. Specifically, the following two methods can be mentioned. In the first method, the two substrates are first arranged opposite each other with a gap (cell gap) between them so that the liquid crystal alignment films face each other. Next, the peripheries of the two substrates are bonded together using a sealant, and a liquid crystal composition is injected into the substrate surfaces and the cell gap defined by the sealant to contact the film surface, and then the injection hole is sealed.

[0092] The second method is called the ODF (One Drop Fill) method. A UV-curable sealant, for example, is applied to a predetermined location on one of two substrates on which a liquid crystal alignment film has been formed, and a liquid crystal composition is then dropped onto several predetermined locations on the liquid crystal alignment film. The other substrate is then attached so that the liquid crystal alignment film faces the other substrate, and the liquid crystal composition is spread over the entire surface of the substrate and brought into contact with the film surface. The entire surface of the substrate is then irradiated with UV light to cure the sealant. In either method, it is desirable to further heat the substrate to a temperature at which the liquid crystal composition assumes an isotropic phase and then slowly cool it to room temperature to remove flow alignment that occurs during liquid crystal filling. If the coating film is subjected to a rubbing treatment, the two substrates are positioned opposite each other so that the rubbing directions on each coating film are at a predetermined angle, for example, perpendicular or antiparallel. For example, an epoxy resin containing a curing agent and aluminum oxide spheres as spacers can be used as the sealant.

[0093] The liquid crystal composition is not particularly limited, and may be any of various liquid crystal compositions containing at least one liquid crystal compound (liquid crystal molecule) and having positive or negative dielectric anisotropy. Hereinafter, a liquid crystal composition having positive dielectric anisotropy will be referred to as a positive liquid crystal, and a liquid crystal composition having negative dielectric anisotropy will be referred to as a negative liquid crystal.

[0094] The liquid crystal composition may contain a liquid crystal compound having a fluorine atom, a hydroxy group, an amino group, a fluorine atom-containing group (e.g., a trifluoromethyl group), a cyano group, an alkyl group, an alkoxy group, an alkenyl group, an isothiocyanate group, a heterocycle, a cycloalkane, a cycloalkene, a steroid skeleton, a benzene ring, or a naphthalene ring, or may contain a compound having two or more rigid moieties (mesogenic skeletons) that exhibit liquid crystallinity in the molecule (e.g., a bimesogenic compound in which two rigid biphenyl structures or terphenyl structures are connected by an alkylene group). The liquid crystal composition may be a liquid crystal composition exhibiting a nematic phase, a liquid crystal composition exhibiting a smectic phase, or a liquid crystal composition exhibiting a cholesteric phase.

[0095] The liquid crystal composition may further contain an additive from the viewpoint of improving the liquid crystal alignment property. Examples of such additives include photopolymerizable monomers such as compounds having a polymerizable group; optically active compounds (e.g., S-811 manufactured by Merck & Co., Ltd.); antioxidants; ultraviolet absorbers; dyes; antifoaming agents; polymerization initiators; and polymerization inhibitors. Examples of positive-type liquid crystals include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, and MLC-7081 manufactured by Merck & Co., Ltd., and PA-1492 manufactured by DIC Corporation. Examples of negative-type liquid crystals include MLC-6608, MLC-6609, MLC-6610, and MLC-7026-100 manufactured by Merck & Co., Ltd. Examples of liquid crystals containing a compound having a polymerizable group include MLC-3023 manufactured by Merck & Co., Ltd.

[0096] The liquid crystal aligning agent of the present invention is also preferably used for a liquid crystal display element (PSA-type liquid crystal display element) manufactured through a step of: having a liquid crystal layer between a pair of substrates equipped with electrodes, disposing a liquid crystal composition containing a polymerizable compound that polymerizes by at least one of active energy rays and heat between the pair of substrates, and polymerizing the polymerizable compound by at least one of irradiation with active energy rays and heating while applying a voltage between the electrodes (hereinafter, this step is also referred to as step (5)). The liquid crystal aligning agent of the present invention is also preferably used for a liquid crystal display element (SC-PVA-type liquid crystal display element) manufactured through a step of having a liquid crystal layer between a pair of substrates equipped with electrodes, disposing a liquid crystal alignment film containing a polymerizable group that polymerizes by at least one of active energy rays and heat between the pair of substrates, and applying a voltage between the electrodes (hereinafter, this step is also referred to as step (6)).

[0097] A liquid crystal display element can be obtained by attaching a polarizing plate to the outer surface of the liquid crystal cell as needed. Examples of the polarizing plate to be attached to the outer surface of the liquid crystal cell include a polarizing plate in which a polarizing film called an "H film" made by stretching and aligning polyvinyl alcohol and absorbing iodine is sandwiched between cellulose acetate protective films, and a polarizing plate made of the H film itself.

[0098] An IPS substrate, which is a comb-teeth electrode substrate used in the IPS mode, has a base material, a plurality of linear electrodes formed on the base material and arranged in a comb-teeth pattern, and a liquid crystal alignment film formed on the base material so as to cover the linear electrodes. Meanwhile, an FFS substrate, which is a comb-teeth electrode substrate used in the FFS mode, has a base material, a surface electrode formed on the base material, an insulating film formed on the surface electrode, a plurality of linear electrodes formed on the insulating film and arranged in a comb-teeth pattern, and a liquid crystal alignment film formed on the insulating film so as to cover the linear electrodes.

[0099] FIG. 1 is a schematic cross-sectional view showing an example of an in-plane switching liquid crystal display element of the present invention, which is an example of an IPS-mode liquid crystal display element. In the in-plane switching liquid crystal display element 1 shown in FIG. 1 , liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2c and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 has a base 2a, a plurality of linear electrodes 2b formed on the base 2a and arranged in a comb-like pattern, and a liquid crystal alignment film 2c formed on the base 2a to cover the linear electrodes 2b. The counter substrate 4 has a base 4b and a liquid crystal alignment film 4a formed on the base 4b. The liquid crystal alignment film 2c is, for example, a liquid crystal alignment film of the present invention. The liquid crystal alignment film 4c is also a liquid crystal alignment film of the present invention. In this in-plane switching liquid crystal display element 1, when a voltage is applied to the linear electrodes 2b, an electric field is generated between the linear electrodes 2b, as indicated by electric field lines L.

[0100] FIG. 2 is a schematic cross-sectional view showing another example of an in-plane switching liquid crystal display element of the present invention, which is an example of an FFS-mode liquid crystal display element. In the in-plane switching liquid crystal display element 1 shown in FIG. 2, liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 having a liquid crystal alignment film 2h and a counter substrate 4 having a liquid crystal alignment film 4a. The comb-shaped electrode substrate 2 includes a base material 2d, a surface electrode 2e formed on the base material 2d, an insulating film 2f formed on the surface electrode 2e, a plurality of linear electrodes 2g formed on the insulating film 2f and arranged in a comb-like pattern, and a liquid crystal alignment film 2h formed on the insulating film 2f so as to cover the linear electrodes 2g. The counter substrate 4 includes a base material 4b and a liquid crystal alignment film 4a formed on the base material 4b. The liquid crystal alignment film 2h is, for example, a liquid crystal alignment film of the present invention. The liquid crystal alignment film 4a is also a liquid crystal alignment film of the present invention. In this IPS LCD element 1, when a voltage is applied to the surface electrodes 2e and the linear electrodes 2g, an electric field is generated between the surface electrodes 2e and the linear electrodes 2g as indicated by electric force lines L.

[0101] The liquid crystal alignment film of the present invention can be used for various purposes other than the above-mentioned purposes, for example, as a liquid crystal alignment film for a retardation film, a liquid crystal alignment film for a scanning antenna or a liquid crystal array antenna, or a liquid crystal alignment film for a transmission-scattering type liquid crystal dimming element. Furthermore, it can also be used for purposes other than liquid crystal alignment films, such as a protective film (e.g., a protective film for a color filter), a spacer film, an interlayer insulating film, an antireflection film, a wiring covering film, an antistatic film, and an insulating film for an electric motor (a gate insulating film for a flexible display).

[0102] The liquid crystal display element of the present invention can be effectively applied to various devices, and can be used in various display devices such as watches, portable games, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, various monitors, liquid crystal televisions, and information displays.

[0103] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The abbreviations of the compounds used and the methods for measuring the physical properties are as follows. (Organic solvents) MeOH: methanol IPA: isopropyl alcohol NMP: N-methyl-2-pyrrolidone BCS: ethylene glycol monobutyl ether (Tetracarboxylic acid dianhydrides) CA-1 to CA-5: compounds represented by the following formulas (CA-1) to (CA-5)

[0104]

[0105] (Diamine) DA-1 to DA-21: Compounds represented by the following formulas (DA-1) to (DA-21), respectively

[0106] Among the above diamines, DA-1 to DA-13 are included in the range of the specific diamine (p). (Reaction Reagent) B-1: A compound represented by the following formula (B-1):

[0107]

[0108] (Additives) AD-1 to AD-4: Compounds represented by the following formulas (AD-1) to (AD-4), respectively

[0109]

[0110] <Measurement of Viscosity> Measurement was carried out at 25°C using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL and a cone rotor TE-1 (1°34', R24).

[0111] <Measurement of Molecular Weight> Measurement was carried out using the following room temperature GPC (gel permeation chromatography) apparatus under the following conditions, and Mn and Mw were calculated as polyethylene glycol and polyethylene oxide equivalent values. GPC apparatus: GPC-101 (Showa Denko K.K.), Column: GPC KD-803 and GPC KD-805 (Showa Denko K.K.) connected in series, Column temperature: 50°C, Eluent: N,N-dimethylformamide (containing lithium bromide monohydrate (LiBr.H) as an additive), ２o-Phosphoric acid (o-Phosphoric acid) 30 mmol / L, tetrahydrofuran (THF) 10 mL / L), Flow rate: 1.0 mL / min. Standard samples for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight: about 900,000, about 150,000, about 100,000, and about 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight: about 12,000, about 4,000, and about 1,000) (manufactured by Polymer Laboratory Co., Ltd.).

[0112] [Synthesis of Monomers] DA-1 to DA-3, DA-6 to DA-8, and DA-11 were synthesized by the methods described below. DA-5 was purchased as a commercially available product (manufactured by Tokyo Chemical Industry Co., Ltd.). DA-4, DA-9, DA-10, DA-12, and DA-13 are novel compounds not previously disclosed in literature, and their synthesis methods are described in detail below. The products described in Monomer Synthesis Examples 1 to 13 below are １ The product was identified by H-NMR analysis (analysis conditions are as follows): Apparatus: Fourier transform superconducting nuclear magnetic resonance spectrometer (FT-NMR) "AVANCE III" (manufactured by BRUKER) 500 MHz Solvent: deuterated dimethyl sulfoxide (DMSO-d ６ ) Standard substance: tetramethylsilane (TMS)

[0113] <Monomer Synthesis Example 1: Synthesis of DA-1> Terephthalaldehyde (8.0 g, 59.6 mmol), MeOH (80 g), and isopropylamine (8.8 g, 149 mmol) were added to a 500 mL four-neck flask and stirred at room temperature (25 ° C) for 2 hours. Subsequently, sodium borohydride (2.48 g, 65.6 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After completion of the reaction, the solution was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10% by mass aqueous potassium hydroxide solution was added to the solid and stirred at room temperature for 2 hours, and chloroform (64 g) was added to the reaction solution and extracted. The organic layer was washed four times with pure water (80 g), and the extracted organic layer was concentrated and dried under reduced pressure at 40 ° C. to obtain DA-1 (yield: 11.7 g, 53.1 mmol, yield: 89%, whitish-yellow liquid). １ H-NMR (500MHz, [D ６]-DMSO): δ (ppm) = 7.24 (s, 4H), 3.64 (s, 4H), 2.68 (m, 2H), 1.75 (s, 2H), 0.982 (d, 12H).

[0114] <Monomer Synthesis Example 2: Synthesis of DA-2> Terephthalaldehyde (20.0 g, 149 mmol), MeOH (200 g), and benzylamine (35.1 g, 328 mmol) were added to a 500 mL four-neck flask and heated to reflux for 2 hours. Subsequently, sodium borohydride (6.20 g, 164 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After completion of the reaction, the mixture was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. The solid was recrystallized from a 10% by mass aqueous potassium hydroxide solution and then recrystallized from pure water to obtain DA-2 (yield: 44.9 g, 142 mmol, yield: 95%, white solid). １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 7.26-7.35 (m, 12H), 7.19-7.24 (t, 2H), 3.63-3.67 (d, 8H), 2.53 (s, 2H).

[0115] <Monomer Synthesis Example 3: Synthesis of DA-3> Terephthalaldehyde (16.0 g, 119 mmol), MeOH (160 g), and 3-picolylamine (28.3 g, 262 mmol) were added to a 500 mL four-neck flask and stirred at room temperature for 2 hours. Subsequently, sodium borohydride (4.96 g, 131 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After the reaction was completed, the solution was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10% by mass aqueous solution of potassium hydroxide was added to the solid and stirred at 100°C for 2 hours, and chloroform (320 g) was added to the reaction solution for extraction. The organic layer was washed four times with pure water (160 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (240 g) was added to the crystals, and the mixture was stirred at room temperature. The crystals were filtered and then dried under reduced pressure at 40°C to obtain DA-3 (yield: 21.7 g, 68.1 mmol, yield: 57%, whitish yellow crystals). １ H-NMR (500MHz, [D６ ]-DMSO): δ (ppm) = 8.52 (s, 2H), 8.44 (d, 2H), 7.75 (d, 2H), 7.33 (m, 2H), 7.28 (s, 4H), 3.69 (s, 4H), 3.66 (s, 4H) 2.67 (s, 2H).

[0116] <Monomer Synthesis Example 4: Synthesis of DA-4> Terephthalaldehyde (6.00 g, 44.7 mmol), MeOH (60 g), and 3-(aminomethyl)thiophene (11.1 g, 98.1 mmol) were added to a 500 mL four-neck flask and stirred at room temperature for 2 hours. Subsequently, sodium borohydride (2.88 g, 76.0 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After the reaction was completed, the mixture was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10% by mass aqueous solution of potassium hydroxide was added to the solid, and the mixture was stirred at 100°C for 2 hours. Chloroform (120 g) was added to the reaction solution and extracted. The organic layer was washed four times with pure water (60 g), and the extracted organic layer was concentrated, dried, and allowed to stand at room temperature for 10 minutes to precipitate crystals. Heptane (18 g) was added to the crystals, stirred at 0°C, and filtered. The crystals were then dried under reduced pressure at 40°C to obtain DA-4 (yield: 11.3 g, 34.4 mmol, 77% yield, white crystals). １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 7.37 (d, 2H), 7.27 (s, 4H), 6.95 (m, 4H), 3.84 (s, 4H), 3.68 (s, 4H), 2.67 (s, 2H).

[0117] <Monomer Synthesis Example 5: Synthesis of DA-6> Terephthalaldehyde (16.0 g, 119 mmol), MeOH (160 g), and 2-picolylamine (28.3 g, 262 mmol) were added to a 500 mL four-neck flask and stirred at room temperature for 2 hours. Subsequently, sodium borohydride (5.00 g, 131 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After the reaction was completed, the mixture was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt % aqueous potassium hydroxide solution was added to the solid and stirred at 100°C for 2 hours, and chloroform (320 g) was added to the reaction solution for extraction. The organic layer was washed four times with pure water (160 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (240 g) was added to the crystals, and the mixture was stirred at room temperature, filtered, and then dried to obtain 21.7 g of DA-6 (white-yellow crystals) (yield 57.3%). １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the target DA-6. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 8.48 (d, 2H), 7.75 (t, 2H), 7.46 (d, 2H), 7.29 (s, 4H), 7.23 (m, 2H), 3.77 (s, 4H), 3.70 (s, 4H), 2.70 (s, 2H)

[0118] <Monomer Synthesis Example 6: Synthesis of DA-7> To trans-1,4-cyclohexanediamine (12.0 g, 105 mmol) was added MeOH (120 g) as a solvent, followed by dropwise addition of benzaldehyde (24.5 g, 231 mmol). The mixture was stirred at room temperature for 2 hours. Subsequently, sodium borohydride (4.39 g, 116 mmol) was added with ice cooling, and the mixture was stirred at room temperature for 2 hours. After concentrating at 45°C for 1 hour, the mixture was diluted with acetone and the solution was filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt% aqueous potassium hydroxide solution was added to the solid, and the mixture was stirred at 100°C for 2 hours. Chloroform (360 g) was added to the reaction solution for extraction. The organic layer was washed four times with pure water (240 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (120 g) was added to the crystals, stirred at room temperature, filtered, and then dried to obtain 21.0 g of DA-7 (pale orange solid) (yield 66.0%). １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the desired DA-7. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 7.29 (m, 8H), 7.20 (t, 2H), 3.69 (s, 4H), 2.32 (s, 2H), 1.88 (d, 2H), 1.80 (s, 4H), 0.99 (t, 4H)

[0119] <Monomer Synthesis Example 7: Synthesis of DA-8> 2,6-pyridinedicarboxaldehyde (4.50 g, 33.3 mmol), MeOH (45 g), and benzylamine (7.85 g, 73.3 mmol) were added to a 500 mL four-neck flask and stirred at room temperature for 2 hours. Subsequently, sodium borohydride (1.38 g, 36.6 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After the reaction was completed, the mixture was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt% aqueous potassium hydroxide solution was added to the solid and stirred at 100°C for 2 hours. Chloroform (135 g) was added to the reaction solution and extracted. The organic layer was washed four times with pure water (90 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (45 g) was added to the crystals, stirred at room temperature, filtered, and then dried to obtain 8.87 g of DA-8 (a whitish-yellow oil) (yield 83.7%). of the object １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the desired DA-8. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 7.71 (t, 1H), 7.35 (d, 4H), 7.30 (t, 6H), 7.22 (t, 2H), 3.76 (s, 4H), 3.73 (s, 4H), 2.68 (s, 2H)

[0120] <Monomer Synthesis Example 8: Synthesis of DA-9> Terephthalaldehyde (6.00 g, 44.7 mmol), MeOH (60 g), and pyrazin-2-ylmethanamine (10.7 g, 98.4 mmol) were added to a 500 mL four-neck flask and stirred at room temperature for 2 hours. Subsequently, sodium borohydride (1.86 g, 49.2 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After the reaction was completed, the solution was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt % aqueous potassium hydroxide solution was added to the solid and stirred at 100°C for 2 hours, and chloroform (180 g) was added to the reaction solution for extraction. The organic layer was washed four times with pure water (120 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (60 g) was added to the crystals, stirred at room temperature, filtered, and then dried to obtain 9.20 g of DA-9 (reddish-black oil) (yield 64.3%). １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the desired DA-9. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 8.72 (d, 1H), 8.55 (m, 2H), 8.51 (t, 2H), 7.29 (s, 4H), 3.84 (s, 4H), 3.72 (s, 4H), 2.80 (s, 2H)

[0121] <Monomer Synthesis Example 9: Synthesis of DA-10> 4-Hydroxybenzaldehyde (16.5 g, 13.5 mmol), potassium carbonate (27.9 g, 202 mmol), and DMAc (100 g) were added to 1,2-Bis(tosyloxy)ethane (25.0 g, 67.5 mmol), and the mixture was heated to 105°C. After confirming the completion of the reaction, the mixture was crystallized from purified water (1500 g) and the white solid was filtered off. The resulting crystals were dried to obtain 13.0 g of DA-10-1 (white solid) (yield: 71.4%). １ H-NMR (500MHz) in DMSO-d ６: 9.89 (s, 2H), 7.89 (d, 4H), 7.20 (d, 4H), 4.49 (s, 4H). MeOH (75 g) and 3-picolylamine (4.40 g, 40.7 mmol) were added to the DA-10-1 (5.00 g, 18.5 mmol) obtained above, and the mixture was stirred at room temperature for 2 hours. Subsequently, sodium borohydride (0.768 g, 20.3 mmol) was added with ice cooling, and the mixture was stirred at room temperature for 2 hours. After the reaction was completed, the mixture was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt % aqueous potassium hydroxide solution was added to the solid, and the mixture was stirred at 100 °C for 2 hours. Chloroform (150 g) was added to the reaction solution and extracted. The organic layer was washed four times with pure water (100 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (50 g) was added to the crystals, stirred at room temperature, filtered, and then dried to obtain 4.22 g of DA-10 (white solid) (yield 50.2%). １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the desired DA-10. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 8.52 (s, 2H), 8.44 (d, 2H), 7.74 (d, 2H), 7.33 (m, 2H), 7.26 (d, 4H), 6.93 (d, 4H), 4.28 (s, 4H), 3.67 (s, 4H), 3.62 (s, 4H), 3.34 (s, 2H)

[0122] <Monomer Synthesis Example 10: Synthesis of DA-11> 5-Hydroxypyridine-2-carbaldehyde (19.9 g, 162 mmol), potassium carbonate (33.6 g, 243 mmol), and DMAc (120 g) were added to 1,2-Bis(tosyloxy)ethane (30.0 g, 81 mmol), and the mixture was heated to 105°C. After confirming the completion of the reaction, the mixture was crystallized from purified water (1,800 g) and the white solid was filtered off. The resulting crystals were dried to obtain 13.0 g of DA-11-1 (white solid) (yield: 71.4%). １ H-NMR (500MHz, [D ６]-DMSO): δ (ppm) = 9.91 (s, 2H), 8.56 (d, 2H), 7.96 (d, 2H), 7.67 (m, 2H), 4.62 (s, 4H). To the DA-11-1 (4.50 g, 16.5 mmol) obtained above, MeOH (67.5 g) and benzylamine (3.90 g, 36.4 mmol) were added and stirred at room temperature for 2 hours. Subsequently, sodium borohydride (0.689 g, 18.2 mmol) was added with ice cooling and stirred at room temperature for 2 hours. After completion of the reaction, the solution was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt % aqueous potassium hydroxide solution was added to the solid and stirred at 100 °C for 2 hours. Chloroform (135 g) was added to the reaction solution and extracted. The organic layer was washed four times with pure water (90 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (45 g) was added to the crystals, and the mixture was stirred at room temperature, filtered, and then dried to obtain 2.40 g of DA-11 (white solid) (yield 32.0%). １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the target DA-11. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 8.25 (d, 2H), 7.41 (m, 4H), 7.32 (m, 8H), 7.22 (t, 2H), 4.39 (s, 4H), 3.72 (s, 4H), 3.70 (s, 4H), 2.62 (s, 2H)

[0123] <Monomer Synthesis Example 11: Synthesis of DA-12> To piperazine (15.0 g, 174 mmol), potassium carbonate (52.9 g, 363 mmol) and DMAc (150 g) were added, and the mixture was heated to 105°C. Then, 4-fluorobenzaldehyde (47.5 g, 383 mmol) was added little by little, and the mixture was allowed to react at 105°C. After confirming the completion of the reaction, the white solid was crystallized from pure water (750 g) and filtered off. THF (225 g) was added, and the mixture was washed with a slurry at 65°C, and then immersed in an ice bath for filtration. The crystals obtained after filtration were dried, yielding 8.87 g of DA-12-1 (white solid) (yield: 55.9%). １ H-NMR (500 MHz) in DMSO-d６ : 9.73 (s, 2H), 7.75 (d, 4H), 7.06 (d, 4H), 3.61 (s, 8H). MeOH (120 g) and isopropylamine (3.53 g, 59.8 mmol) were added to the DA-12-1 (8.00 g, 27.2 mmol) obtained above, and the mixture was stirred at room temperature for 2 hours. Subsequently, sodium borohydride (2.57 g, 67.9 mmol) was added with ice cooling, and the mixture was stirred at room temperature for 2 hours. After the reaction was completed, the mixture was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt % aqueous potassium hydroxide solution was added to the solid, and the mixture was stirred at 100 °C for 2 hours. Chloroform (240 g) was added to the reaction solution and extracted. The organic layer was washed four times with pure water (160 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (80 g) was added to the crystals, stirred at room temperature, filtered, and then dried to obtain 8.10 g of DA-12 (white solid) (yield 62.3%). １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the desired DA-12. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 7.19 (d, 4H), 6.93 (d, 4H), 3.59 (s, 4H), 3.23 (s, 8H), 2.68 (m, 2H), 1.68 (s, 2H), 0.979 (d, 12H)

[0124] <Monomer Synthesis Example 12: Synthesis of DA-13> To DA-12-1 (7.00 g, 23.8 mmol), MeOH (105 g) and 3-picolylamine (5.66 g, 52.3 mmol) were added and stirred at room temperature for 2 hours. Subsequently, sodium borohydride (2.25 g, 59.5 mmol) was added with ice cooling, and the mixture was stirred at room temperature for 2 hours. After the reaction was completed, the mixture was diluted with acetone and filtered. 12 N hydrochloric acid was added, and the resulting solid was filtered off. A 10 wt % aqueous solution of potassium hydroxide was added to the solid, and the mixture was stirred at 100°C for 2 hours. Chloroform (210 g) was added to the reaction solution for extraction. The organic layer was washed four times with pure water (140 g), and the extracted organic layer was concentrated, dried, and left to stand overnight at room temperature to precipitate crystals. Heptane (70 g) was added to the crystals, and the mixture was stirred at room temperature, filtered, and then dried to obtain 3.55 g of DA-13 (white solid) (yield 31.1%). １ The results of H-NMR are shown below, and it was confirmed that the obtained solid was the target DA-13. １ H-NMR (500MHz, [D ６ ]-DMSO): δ (ppm) = 8.51 (s, 2H), 8.43 (d, 2H), 7.74 (d, 2H), 7.33 (m, 2H), 7.21 (d, 4H), 6.95 (d, 4H), 3.67 (s, 4H), 3.59 (s, 4H), 3.25 (s, 8H), 2.57 (s, 2H)

[0125] [Polymer Synthesis] <Synthesis Example 1> DA-1 (1.05 g, 4.78 mmol) and NMP (9.50 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature (25°C) while introducing nitrogen. Thereafter, CA-1 (1.39 g, 4.73 mmol) and NMP (8.50 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-1) with a solids concentration of 12% by mass (viscosity: 37 mPa s). The Mn of this polyamic acid was 4,828 and the Mw was 10,676. The polyamic acid (A-1) had the following partial structure (a0-A-1) and is included in the scope of polymer (P0).

[0126]

[0127] Synthesis Example 2 DA-2 (2.53 g, 8.00 mmol) and NMP (22.8 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (2.33 g, 7.92 mmol) and NMP (12.9 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-2) with a solids concentration of 12% by mass (viscosity: 17 mPa s). The Mn of this polyamic acid was 2,867 and the Mw was 8,933. The polyamic acid (A-2) had the following partial structure (a0-A-2) and is included in the scope of polymer (P0).

[0128]

[0129] Synthesis Example 3 DA-3 (2.55 g, 8.00 mmol) and NMP (22.9 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (2.33 g, 7.92 mmol) and NMP (12.8 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-3) with a solids concentration of 12% by mass (viscosity: 13 mPa s). The polyamic acid had an Mn of 2,048 and an Mw of 5,041. The polyamic acid (A-3) had the following partial structure (a0-A-3) and is included in the scope of polymer (P0).

[0130]

[0131] Synthesis Example 4 DA-4 (1.97 g, 6.00 mmol) and NMP (17.7 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (1.75 g, 5.94 mmol) and NMP (9.50 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-4) with a solids concentration of 12% by mass (viscosity: 19 mPa s). The Mn of this polyamic acid was 3,618 and the Mw was 11,403. The polyamic acid (A-4) had the following partial structure (a0-A-4) and is included in the scope of polymer (P0).

[0132]

[0133] Synthesis Example 5 DA-5 (2.40 g, 10.00 mmol) and NMP (27.6 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (2.91 g, 9.90 mmol) and NMP (11.30 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-5) with a solids concentration of 12% by mass (viscosity: 18 mPa s). The Mn of this polyamic acid was 3,823 and the Mw was 9,215. The polyamic acid (A-5) had the following partial structure (a0-A-5) and is included in the scope of polymer (P0).

[0134]

[0135] Synthesis Example 6 DA-6 (2.23 g, 7.00 mmol) and NMP (20.1 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (2.04 g, 6.93 mmol) and NMP (11.20 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-6) with a solids concentration of 12% by mass (viscosity: 47 mPa s). The Mn of this polyamic acid was 7,095 and the Mw was 22,170. The polyamic acid (A-6) had the following partial structure (a0-A-6) and is included in the scope of polymer (P0).

[0136]

[0137] Synthesis Example 7 DA-7 (2.06 g, 7.00 mmol) and NMP (18.5 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (2.04 g, 6.93 mmol) and NMP (11.50 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-7) with a solids concentration of 12% by mass (viscosity: 21 mPa s). The Mn of this polyamic acid was 4,711 and the Mw was 11,526. The polyamic acid (A-7) had the following partial structure (a0-A-7) and is included in the scope of polymer (P0).

[0138]

[0139] Synthesis Example 8 DA-8 (2.22 g, 7.00 mmol) and NMP (20.0 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while feeding nitrogen. Thereafter, CA-1 (2.04 g, 6.93 mmol) and NMP (11.20 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-8) with a solids concentration of 12% by mass (viscosity: 17 mPa s). The Mn of this polyamic acid was 3,590 and the Mw was 11,228. The polyamic acid (A-8) had the following partial structure (a0-A-8) and is included in the scope of polymer (P0).

[0140]

[0141] Synthesis Example 9 DA-9 (2.24 g, 7.00 mmol) and NMP (20.2 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (2.04 g, 6.93 mmol) and NMP (11.20 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-9) with a solids concentration of 12% by mass (viscosity: 17 mPa s). The Mn of this polyamic acid was 3,602 and the Mw was 15,171. The polyamic acid (A-9) had the following partial structure (a0-A-9) and is included in the scope of polymer (P0).

[0142]

[0143] Synthesis Example 10 DA-10 (1.46 g, 3.20 mmol) and NMP (13.1 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (0.93 g, 3.17 mmol) and NMP (4.40 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-10) with a solids concentration of 12% by mass (viscosity: 38 mPa s). The polyamic acid had an Mn of 4,052 and an Mw of 10,352. The polyamic acid (A-10) has the following partial structure (a0-A-10) and is included in the scope of polymer (P0).

[0144]

[0145] Synthesis Example 11 DA-11 (1.36 g, 3.00 mmol) and NMP (12.3 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-1 (0.87 g, 2.97 mmol) and NMP (4.10 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-4) with a solids concentration of 12% by mass (viscosity: 17 mPa s). The Mn of this polyamic acid was 3,202 and the Mw was 10,745. The polyamic acid (A-11) had the following partial structure (a0-A-11) and is included in the scope of polymer (P0).

[0146]

[0147] [Polymer Synthesis] <Synthesis Example 12> DA-12 (1.33 g, 3.50 mmol) and NMP (9.80 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature (25°C) while introducing nitrogen. Thereafter, CA-1 (1.02 g, 3.47 mmol) and NMP (7.50 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-12) with a solids concentration of 12% by mass (viscosity: 28 mPa s). The Mn of this polyamic acid was 4,750 and the Mw was 10,145. The polyamic acid (A-12) had the following partial structure (a0-A-12) and is included in the scope of polymer (P0).

[0148]

[0149] [Polymer Synthesis] <Synthesis Example 13> DA-13 (1.44 g, 3.00 mmol) and NMP (10.50 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature (25°C) while introducing nitrogen. Thereafter, CA-1 (0.87 g, 2.97 mmol) and NMP (6.40 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-13) with a solids concentration of 12% by mass (viscosity: 47 mPa s). The Mn of this polyamic acid was 4,836 and the Mw was 10,789. The polyamic acid (A-13) had the following partial structure (a0-A-13) and is included in the scope of polymer (P0).

[0150]

[0151] Synthesis Example 14 DA-2 (2.06 g, 6.50 mmol) and NMP (18.5 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-2 (1.40 g, 6.44 mmol) and NMP (6.90 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-14) with a solids concentration of 12% by mass (viscosity: 21 mPa s). The Mn of this polyamic acid was 4,281 and the Mw was 10,905. The polyamic acid (A-14) had the following partial structure (a0-A-14) and is included in the scope of polymer (P0).

[0152]

[0153] Synthesis Example 15 DA-3 (2.23 g, 7.00 mmol) and NMP (20.1 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-2 (1.51 g, 6.93 mmol) and NMP (7.4 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-15) with a solids concentration of 12% by mass (viscosity: 11 mPa s). The polyamic acid had an Mn of 2,820 and an Mw of 4,900. The polyamic acid (A-15) had the following partial structure (a0-A-15) and is included in the scope of polymer (P0).

[0154]

[0155] Synthesis Example 16 DA-2 (1.74 g, 5.5 mmol) and NMP (20.0 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-3 (1.76 g, 5.45 mmol) and NMP (5.60 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-16) with a solids concentration of 12% by mass (viscosity: 15 mPa s). The Mn of this polyamic acid was 2,073 and the Mw was 8,932. The polyamic acid (A-16) had the following partial structure (a0-A-16) and is included in the scope of polymer (P0).

[0156]

[0157] Synthesis Example 17 DA-2 (1.74 g, 5.50 mmol) and NMP (20.0 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while introducing nitrogen. Thereafter, CA-4 (1.69 g, 5.45 mmol) and NMP (5.10 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-17) with a solids concentration of 12% by mass (viscosity: 12 mPa s). The polyamic acid had an Mn of 1,513 and an Mw of 5,675. The polyamic acid (A-17) had the following partial structure (a0-A-17) and is included in the scope of polymer (P0).

[0158]

[0159] Synthesis Example 18 DA-14 (1.80 g, 12.0 mmol) and NMP (20.7 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and dissolved by stirring at room temperature while supplying nitrogen. Thereafter, CA-1 (3.49 g, 11.9 mmol) and NMP (18.1 g) were added, and the mixture was stirred at 50°C for 18 hours to obtain a solution of polyamic acid (A-18) with a solids concentration of 12% by mass (viscosity: 187 mPa s). The Mn of this polyamic acid was 4,753 and the Mw was 9,682. The polyamic acid (A-18) had the following partial structure (c-A-18):

[0160]

[0161] Synthesis Example 19: DA-15 (0.64 g, 3.0 mmol), DA-16 (2.22 g, 5.0 mmol), DA-17 (0.80 g, 2.0 mmol), and NMP (32.9 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was stirred at room temperature while introducing nitrogen to dissolve the mixture. Thereafter, CA-5 (2.13 g, 9.5 mmol) and NMP (9.5 g) were added, and the mixture was stirred at 40°C for 18 hours to obtain a solution of polyamic acid (A-19) with a solids concentration of 12% by mass (viscosity: 246 mPa s). The Mn of this polyamic acid was 10,028 and the Mw was 24,122.

[0162] Synthesis Example 20: DA-18 (0.81 g, 7.5 mmol), DA-19 (9.16 g, 7.5 mmol), DA-17 (3.98 g, 10.0 mmol), DA-20 (3.66 g, 15.0 mmol), DA-21 (2.72 g, 10.0 mmol), and NMP (139.1 g) were added to a 50 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and the mixture was dissolved by stirring at room temperature while supplying nitrogen. Thereafter, CA-5 (10.70 g, 47.8 mmol) and NMP (28.1 g) were added, and the mixture was stirred at 40°C for 18 hours to obtain a solution of polyamic acid (A-20) with a solids concentration of 12% by mass (viscosity: 233 mPa s). The Mn of this polyamic acid was 9,546 and the Mw was 23,698.

[0163] The types and amounts of the tetracarboxylic acid components and diamine components used in Synthesis Examples 1 to 20 are shown in Table 1.

[0164]

[0165] [Carboxylic Acid Protection of Polymer] <Carboxylic Acid Protection of Polymer Synthesis Example 21> B-1 (0.43 g, 1 molar equivalent relative to the carboxylic acid of A-2) was added to A-2 (5.00 g, 12 wt% NMP solution) in a 20 mL vial, and the mixture was purged with nitrogen, followed by stirring at room temperature for 24 hours to allow the reaction to proceed. After completion of the reaction, the reaction solution was added dropwise to IPA (30.0 g) with stirring, and the precipitated solid was recovered by suction filtration. The recovered solid was redissolved to form a 12 wt% NMP solution, and the process of adding dropwise to IPA (30.0 g) with stirring and washing by suction filtration was repeated twice. The washed solid was dried under reduced pressure to obtain a polyamic acid powder in which the carboxylic acid was protected with a tertiary butyl group (yield: 0.87 g, carboxylic acid protection rate: 67%). NMP (4.4 g) was added to this polyamic acid powder (0.6 g) and dissolved by stirring at room temperature for 24 hours to obtain a solution of polyamic acid (A-21) with a solids concentration of 12 mass % (viscosity: 12 mPa s). The polyamic acid had an Mn of 6,018 and an Mw of 9,992. The polyamic acid (A-21) has the following partial structure (a0-A-21) and is included in the scope of polymer (P0).

[0166]

[0167] Polymer Carboxylic Acid Protection Synthesis Example 22: A-2 (5.00 g, 12% by mass solution in NMP) and B-1 (2.14 g, 5 molar equivalents relative to the carboxylic acid of A-2) were added to a 20 mL vial, and the mixture was purged with nitrogen and then stirred at room temperature for 24 hours to allow the reaction to proceed. After completion of the reaction, the reaction solution was added dropwise to IPA (30.0 g) with stirring, and the precipitated solid was recovered by suction filtration. The recovered solid was redissolved to form a 12% by mass NMP solution, and the process of adding dropwise to IPA (30.0 g) with stirring and washing by suction filtration was repeated twice. The washed solid was dried under reduced pressure to obtain a polyamic acid powder in which the carboxylic acid was protected with tertiary butyl groups (yield: 1.05 g, carboxylic acid protection rate: 94%). NMP (4.4 g) was added to this polyamic acid powder (0.6 g) and dissolved by stirring at room temperature for 24 hours to obtain a solution of polyamic acid (A-22) with a solids concentration of 12 mass % (viscosity: 12 mPa s). The polyamic acid had an Mn of 5,707 and an Mw of 9,254. The polyamic acid (A-22) has the following partial structure (a0-A-22) and is included in the scope of polymer (P0).

[0168]

[0169] The types and amounts of polyamic acids and reaction reagents used in Synthesis Examples 21 and 22 are shown in Table 2.

[0170]

[0171] [Preparation of Liquid Crystal Alignment Agent] Example 1 The polyamic acid solution (A-1) obtained in Synthesis Example 1 was diluted with NMP and BCS, and the diluted solution was stirred at room temperature (25°C) for 2 hours to obtain a liquid crystal alignment agent (AL-1) having a mass ratio of polyamic acid solid content to each solvent (polyamic acid solid content:NMP:BCS) of 5:75:20.

[0172] <Examples 2 to 19 and Comparative Example 1> By performing the same operation as in Example 1 except that the polyamic acid solution used was changed as shown in Table 3, liquid crystal aligning agents AL-2 to AL-19, which are Examples 2 to 19 of the present invention, and liquid crystal aligning agent AL-C1, which is Comparative Example 1, were obtained.

[0173] Example 20 NMP, BCS, AD-1 (1 mass % NMP solution), and AD-2 (10 mass % NMP solution) were added to the polyamic acid solution (A-2) obtained in Synthesis Example 2, and the mixture was stirred at room temperature (25°C) for 2 hours, thereby obtaining a liquid crystal aligning agent (AL-20) in which the mass ratio of the polyamic acid solid content to each solvent (polyamic acid solid content:NMP:BCS) was 5:75:20.

[0174] <Examples 21 and 22> The liquid crystal aligning agents AL-21 and AL-22, which are Examples 21 and 22 of the present invention, were obtained by the same operation as in Example 20, except that the additives used were changed as shown in Table 3.

[0175] Example 23 The polyamic acid solution (A-2) obtained in Synthesis Example 2 and the polyamic acid solution (A-19) obtained in Synthesis Example 19 were diluted with NMP and BCS so that the mass ratio of the two types of polymer solid contents became 50:50, and the mixture was stirred at room temperature (25°C) for 2 hours to obtain a liquid crystal aligning agent (AL-23) in which the mass ratio of the polyamic acid solid content to each solvent (polyamic acid solid content:NMP:BCS) became 5:75:20.

[0176] <Example 24 and Comparative Examples 2 and 3> By performing the same operation as in Example 23 above, except that the polyamic acid solution used was changed as shown in Table 3, the liquid crystal aligning agent AL-24 of the present invention as Example 24 and the liquid crystal aligning agents AL-C2 and AL-C3 of Comparative Examples 2 and 3 were obtained.

[0177]

[0178] In Table 3, the numerical values ​​for Additive 1 and Additive 2 represent the proportion (parts by mass) of the additive relative to 100 parts by mass of the polyamic acid component.

[0179] [Fabrication of FFS-Driven Liquid Crystal Cell] A liquid crystal cell with the configuration of an FFS-mode liquid crystal display element was fabricated. First, a substrate with electrodes was prepared. The substrate was a rectangular glass substrate measuring 30 mm x 35 mm and 0.7 mm thick. A solid-patterned ITO electrode constituting a common electrode was formed on the substrate as a first layer. A SiN (silicon nitride) film deposited by CVD (chemical vapor deposition) was formed on the first common electrode as a second layer. The second SiN film had a thickness of 300 nm, which served as an interlayer insulating film. A comb-shaped pixel electrode formed by patterning an ITO film as a third layer was placed on the second SiN film. Two pixels, a first pixel and a second pixel, were formed, each measuring 10 mm long and 5 mm wide. This electrode-equipped substrate had a structure in which the first common electrode and the third pixel electrode were insulated by the second SiN film. The pixel electrode of the third layer had a comb-like shape with the central portion bent at an interior angle of 160° and multiple electrode lines, each 3 μm wide, arranged parallel to each other at intervals of 6 μm. One pixel was formed by multiple electrode lines and had a first region and a second region separated by a line connecting the bent portions.

[0180] The liquid crystal alignment agents (AL-C1), (AL-1) to (AL-19) obtained in Comparative Example 1 and Examples 1 to 19 were each filtered through a 1.0 μm pore size filter and then spin-coated onto the electrode-attached substrate (hereinafter referred to as the electrode substrate) and a glass substrate (hereinafter referred to as the counter substrate) with a 3.3 μm-high columnar spacer and an ITO film formed on the backside. The resulting substrate was dried on a hot plate at 80°C for 2 minutes and then baked in a hot air circulating oven at 230°C for 20 minutes to form a 100 nm thick coating. This coating was then subjected to a rubbing alignment treatment (roller diameter: 120 mm, roller rotation speed: 500 rpm, movement speed: 30 mm / sec, indentation length: 0.3 mm) using a rayon cloth (HY-5318 manufactured by Hyperflex). The substrate was then ultrasonically cleaned in pure water for 1 minute, water droplets removed with an air blower, and then dried in an oven at 80°C for 15 minutes to obtain a substrate with a liquid crystal alignment film. The liquid crystal alignment film formed on the electrode substrate was oriented so that the direction dividing the pixel bends was perpendicular to the liquid crystal alignment direction. The alignment film formed on the counter substrate was oriented so that the alignment direction of the liquid crystal on the electrode substrate was aligned with the alignment direction of the liquid crystal on the counter substrate when the liquid crystal cell was fabricated. The two substrates were combined into a pair, and a sealant (Mitsui Chemicals, Inc., XN-1500T) was printed on one substrate using a dispenser. Another substrate was then attached to the pair, facing each other so that the alignment directions of the liquid crystal alignment films were aligned at 0°. The bonded substrates were then pressure-bonded and heated in a circulating hot air oven at 150°C for 60 minutes to cure the sealant, producing an empty cell. A positive liquid crystal PA-1492 (DIC Corporation) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS drive liquid crystal cell. The obtained liquid crystal cell was then heated at 120°C for 1 hour and allowed to stand at 23°C overnight before being used for evaluation.<Formation of Liquid Crystal Alignment Film by Photo-Alignment Method> The liquid crystal alignment agents (AL-C2), (AL-C3), (AL-23), and (AL-24) obtained in Comparative Examples 2 and 3 and Examples 23 and 24 were each filtered through a filter with a pore size of 1.0 μm. The resulting solution was then applied by spin coating to the electrode-attached substrate (hereinafter referred to as the electrode substrate) and a glass substrate (hereinafter referred to as the counter substrate) having a 4 μm-high columnar spacer and an ITO film formed on the back surface. After drying for 2 minutes on a hot plate at 80 ° C, the substrate was baked for 30 minutes in an IR oven at 230 ° C to form a coating film with a thickness of 80 nm. 300 mJ / cm of polarized ultraviolet light with a wavelength of 254 nm was applied to the coating surface through a 240 nm low-cut filter and a polarizer. ２ The substrate was then irradiated with UV light and baked for 30 minutes in an IR oven at 230°C to obtain a substrate with a liquid crystal alignment film. The liquid crystal alignment film formed on the electrode substrate was oriented so that the direction dividing the interior angles of the pixel bends was perpendicular to the alignment direction of the liquid crystal. The liquid crystal alignment film formed on the counter substrate was oriented so that the alignment direction of the liquid crystal on the electrode substrate coincided with the alignment direction of the liquid crystal on the counter substrate when the liquid crystal cell was fabricated. The two substrates were combined into a pair, and a sealant (Mitsui Chemicals, Inc., XN-1500T) was printed on one substrate using a dispenser. Another substrate was then attached to the pair, facing each other with the alignment directions of the liquid crystal alignment films aligned at 0°. The bonded substrates were then pressure-bonded and heated in a circulating hot air oven at 150°C for 60 minutes to harden the sealant, producing an empty cell. A positive liquid crystal PA-1492 (DIC Corporation) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS drive liquid crystal cell. The obtained FFS drive liquid crystal cell was then heated at 120°C for 1 hour and left at 23°C overnight before being used for evaluation.

[0181] [Measurement of Relaxation Rate of Accumulated Charge] The liquid crystal cell prepared above was placed between two polarizing plates arranged with their polarization axes perpendicular to each other. With the pixel electrode and the common electrode shorted and at the same potential, an LED backlight was irradiated from below the two polarizing plates. The angle of the liquid crystal cell was adjusted so that the brightness of the LED backlight transmitted through the two polarizing plates was minimized. Next, a 30 Hz AC voltage was applied to the liquid crystal cell, and the AC voltage at which the relative transmittance was 23% was calculated as the driving voltage. For image retention evaluation, the liquid crystal cell was driven by applying a 30 Hz AC voltage at which the relative transmittance was 23%, while simultaneously applying a 1 V DC voltage for 30 minutes. After that, the application of the DC voltage alone was stopped, and the cell was driven by AC voltage alone for another 10 minutes, and the relative transmittance was measured. The evaluation criteria were as follows: if the relative transmittance relaxed to 25% or less within 10 minutes after the application of DC voltage was stopped, it was marked as "Good"; if it took 10 minutes or more for the relative transmittance to drop to 25% or less, it was marked as "Poor." The image retention evaluation according to the above-mentioned method was performed under a temperature condition where the temperature of the liquid crystal cell was 23°C. In addition, in Table 4 below, the "-" in Comparative Example 1 indicates that the relaxation rate of the accumulated charge was not measured.

[0182] [Evaluation of Photoresponsiveness] The liquid crystal cell prepared above was placed between two polarizing plates arranged so that their polarization axes were perpendicular to each other, and the LED backlight was turned on with no voltage applied. The angle of the liquid crystal cell was adjusted so that the brightness of the transmitted light was minimized. Next, a VT curve (voltage-transmittance curve) was measured while applying an AC voltage of 30 Hz to the liquid crystal cell, and the AC voltage at which the relative transmittance was 23% was calculated as the driving voltage. The liquid crystal cell was then left in the dark for 72 hours.

[0183] In the photoresponse measurement, a 30 Hz AC voltage was applied at the same time as the backlight was turned on, resulting in a relative transmittance of 23%, and the liquid crystal cell was driven for 30 minutes to track the flicker amplitude. The flicker amplitude was measured by reading the transmitted light from the LED backlight, which passed through two polarizing plates and the liquid crystal cell between them, using a Data Collection / Data Logger Switch Unit 34970A (manufactured by Agilent Technologies) connected via a photodiode and an I-V conversion amplifier. The flicker level was calculated based on this data using the following formula: Flicker Level (%) = {Flicker Amplitude / (2 × z)} × 100. In the above formula, z is the luminance value measured by the Data Collection / Data Logger Switch Unit 34970A when driven with a 30 Hz AC voltage at a relative transmittance of 23%. The evaluation of photoresponsiveness was performed by defining the difference between the maximum flicker level and the maximum value of the flicker level reached after 30 minutes of LED backlighting and AC voltage application as "good" and the difference between the maximum value and the initial flicker level as "poor" if the difference was 0.6% or more. The evaluation of the flicker level according to the above-described method was performed under the temperature condition of the liquid crystal cell at 23°C.

[0184] Table 4 shows the evaluation results of the relaxation speed of accumulated charges and flicker of the liquid crystal cells using the liquid crystal alignment agents of Examples 1 to 19, 23, and 24 and Comparative Examples 1 to 3.

[0185] As shown in Table 4, the liquid crystal display elements using the liquid crystal alignment agents of Examples 1 to 11, 14 to 19, and 24 were good in both the relaxation speed of accumulated charges and the photoresponsiveness. The liquid crystal display elements using the liquid crystal alignment agents of Examples 12, 13, and 23 were good in the relaxation speed of accumulated charges.

[0186] REFERENCE SIGNS LIST 1 IPS LCD element 2 Comb-tooth electrode substrate 2a Base material 2b Linear electrode 2c Liquid crystal alignment film 2d Base material 2e Planar electrode 2f Insulating film 2g Linear electrode 2h Liquid crystal alignment film 3 Liquid crystal 4 Counter substrate 4a Liquid crystal alignment film 4b Base material L Electric field lines

[0187] The entire contents of the specification, claims, drawings and abstract of Japanese Patent Application No. 2023-183784 filed on October 26, 2023 are hereby incorporated by reference as the disclosure of the present invention.

Claims

1. A liquid crystal aligning agent comprising at least one polymer (P0) selected from the group consisting of a polyimide precursor having a partial structure (a0) represented by the following formula (0) and a polyimide which is an imidized product of the polyimide precursor: (In the formula, ** represents a bond bonded to a saturated hydrocarbon group. ３ is a branched alkyl group having 3 to 6 carbon atoms, or *-A ４ -Y ２ Represents. A ４ represents an alkylene group having 1 to 6 carbon atoms; Y ２ represents an aromatic group, and * represents a bond. ２ Any hydrogen atom of the aromatic group in may be replaced with a monovalent group. X represents an aromatic group having a valence of (n+2). Ｄ represents a hydrogen atom or a protecting group which is substituted by a hydrogen atom by heat, R Ｄ If there are multiple R Ｄ may be the same or different, and n is an integer from 1 to 8.

2. The liquid crystal aligning agent according to claim 1, wherein the polymer (P0) is at least one polymer (P) selected from the group consisting of a polyimide precursor obtained by using a tetracarboxylic acid component containing a tetracarboxylic dianhydride represented by the following formula (1) and a diamine component containing a diamine represented by the following formula (2), and a polyimide which is an imidized product of the polyimide precursor. (X ａ represents a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. ２ represents a divalent organic group having 2 to 42 carbon atoms and a saturated hydrocarbon group. ２ At least one of the amino groups bonded to X ２ A bonds to the saturated hydrocarbon group of ３ are each independently a branched alkyl group having 3 to 6 carbon atoms, or *-A ４ -Y ２ Represents. A ４ represents an alkylene group having 1 to 6 carbon atoms; Y ２ represents an aromatic group, and * represents a bond. ２ Any hydrogen atom of the aromatic group in may be replaced with a monovalent group.

3. The above X ２ The liquid crystal aligning agent according to claim 2, wherein *-Z is a structure represented by the following formula (3): ２ -(Y3-Z3) ｎ -* (3) (Y3 represents a divalent organic group having 6 to 30 carbon atoms containing one or more ring structures. Z2 and Z3 each independently represent a divalent chain-like saturated hydrocarbon group having 1 to 6 carbon atoms or an alicyclic hydrocarbon group having 4 to 6 carbon atoms. n is an integer of 0 to 1. Y ３ Any hydrogen atom in the ring structure in may be replaced with a monovalent group. * represents a bond.) 4. The above Y ３ The liquid crystal aligning agent according to claim 3, wherein is a structure represented by the following formula (4): (L is -CH ２ -, -O-, -C(=O)-, -N(R)- (wherein R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), a cyclohexylene group, or an alkylene group having 2 to 18 carbon atoms. However, any -CH ２ - may be substituted by -O-, -O-C(=O)-, -C(=O)-, -N(R)- (wherein R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -N(R)-C(=O)- (wherein R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), a cyclohexylene group, or a phenylene group. ４ represents an aromatic group, an alicyclic hydrocarbon group, or an alicyclic hydrocarbon group containing a nitrogen atom selected from a piperidinediyl group and a piperazinediyl group. ４ When a plurality of R are present, they may be the same or different. ４ represents a halogen atom, or an alkyl or alkoxy group having 1 to 5 carbon atoms, any hydrogen atom of the alkyl or alkoxy group may be substituted with a halogen atom, and any hydrocarbon group may be substituted with an amino group protected with a tert-butoxycarbonyl group. Each of the multiple a's is independently an integer of 0 to 4, b is an integer of 1 to 3, and c is an integer of 0 to 1. R ４ When a is present in a plurality of groups, each group may be the same or different. * represents a bond.

5. The above-mentioned L is -O-, -O-C(=O)-, -C(=O)-, -N(R)- (R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -N(R)-C(=O)- (R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -N(R)-C(=O)-N(R)- (R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group. The two R's may be the same or different), -(CH ２ ) ｐ -, -O-(CH ２ ) ｐ -O-, -(CH ２ ) ｐ -OC(=O)-(CH ２ ) ｑ -, -(CH ２ ) ｐ -N(R)-(CH ２ ) ｑ -(R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group), -(CH ２ ) ｐ -N(R)-C(=O)-N(R)-(CH ２ ) ｑ -(R represents a hydrogen atom, a methyl group, or a tert-butoxycarbonyl group. The two R's may be the same or different.), -O-(CH ２ ) ｐ -O-(CH ２ ) ｑ -O-, -(CH ２ ) ｐ’ -OC(=O)-(CH ２ ) ｑ -C(=O)-O-(CH ２ ) ｒ’ -, -(CH ２ ) ｐ’ -C(=O)-O-(CH ２ ) ｑ -OC(=O)-(CH ２ ) ｒ’ -, -(CH ２ ) ｐ’ -OC(=O)-Q-C(=O)-O-(CH ２ ) ｑ’ -(Q represents a phenylene group or a cyclohexylene group), or -(CH ２ ) ｐ’ -C(=O)-O-Q-OC(=O)-(CH ２ ) ｑ’ -(Q represents a phenylene group or a cyclohexylene group). (p represents an integer of 1 to 6. q represents an integer of 1 to 6. p', q', and r' each independently represent an integer of 0 to 6. In addition, 0≦p'+q' ≦10 and 2≦p'+q+r' ≦16 are satisfied.) 6. The diamine represented by the formula (2) is a diamine represented by the following formula (D Ａ -1) to (D Ａ The liquid crystal aligning agent according to claim 2, which is a diamine represented by any one of the following formulas: (The above formula (D Ａ -1) to (D Ａ In formula (D-24), m is an integer of 0 to 6, and m1, m2, n1, and n2 each independently are an integer of 1 to 6. Ａ -1) to (D Ａ The hydrogen atom on the benzene ring in -24) may be substituted with a monovalent substituent.

7. The liquid crystal aligning agent according to claim 2, wherein the amount of the diamine represented by the formula (2) used is 5 mol % or more per 1 mol of the diamine component used in the production of the polymer (P).

8. X in the above formula (1) ａ The liquid crystal aligning agent according to claim 2, wherein the structure is selected from the following formulas (Xa-1) and (Xa-2): In formulas (Xa-1) to (Xa-2), j and k are integers of 0 or 1; １ and A ２ are each independently a single bond, -O-, -C(=O)-, -O-C(=O)-, a phenylene group, or -S(=O) ２ -, or -NR-C(=O)- (R represents a hydrogen atom or a methyl group). ２ may be the same or different. * represents a bond.) 9. The liquid crystal aligning agent according to claim 8, wherein the formulas (Xa-1) and (Xa-2) are any of structures selected from the following formulas (Xa-3) to (Xa-18): (* represents a bond.) 10. The liquid crystal aligning agent according to claim 2, wherein the amount of the tetracarboxylic dianhydride represented by the formula (1) and its derivatives used is 10 mol % or more per mol of the total tetracarboxylic acid components used in the production of the polymer (P).

11. A liquid crystal alignment film obtained from the liquid crystal aligning agent according to any one of claims 1 to 10.

12. A liquid crystal display device comprising the liquid crystal alignment film of claim 11.

13. A method for manufacturing a liquid crystal display element, comprising the following steps (1) to (3): step (1): applying the liquid crystal alignment agent according to any one of claims 1 to 10 onto a substrate; step (2): baking the applied liquid crystal alignment agent to obtain a film; and step (3): performing an alignment treatment on the film obtained in step (2).

14. The following formula (D Ａ -10), (D Ａ -11), (D Ａ -17), (D Ａ -18), or (D Ａ -24) is a diamine represented by the formula: (Formula (D Ａ -10), (D Ａ -11), (D Ａ -17), (D Ａ -18), (D Ａ In formula (D-24), m1, m2, n1, and n2 each independently represent an integer of 1 to 6. Ａ -10), (D Ａ -11), (D Ａ -17), (D Ａ -18), (D Ａ The hydrogen atom on the benzene ring in -24) may be substituted with a monovalent substituent.

15. A polymer obtained from a diamine component comprising the diamine according to claim 14.

16. A polyimide which is a polyimide precursor or an imidized product thereof obtained by a polycondensation reaction between a diamine component containing the diamine according to claim 14 and a tetracarboxylic acid component.