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

Abstract

To provide a liquid crystal alignment film that exhibits excellent adhesion (close adhesion) between the polyimide-based liquid crystal alignment film and a sealing agent or a substrate; a liquid crystal aligning agent therefor; and a liquid crystal display device provided with the liquid crystal alignment film.SOLUTION: Provided are a diamine having a structure represented by the following formula, a polymer obtained therefrom, and a liquid crystal aligning agent containing the polymer. Refer to the specification for symbols in the formula.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polymer having a protecting group which is substituted with a hydrogen atom by heat, which is used in a liquid crystal display element, a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element using the same, and a novel diamine used therein. [Background technology]

[0002] Various driving methods have been developed for liquid crystal display elements, which differ in electrode structure, physical properties of the liquid crystal molecules used, manufacturing process, etc., and known liquid crystal display elements include TN (twisted nematic) type, STN (super-twisted nematic) type, VA (vertical alignment) type, MVA (multi-domain vertical alignment) type, IPS (in-plane switching) type, FFS (fringe field switching) type, and PSA (polymer-sustained alignment) type. These liquid crystal display elements are equipped with a liquid crystal alignment film to align the liquid crystal molecules. The liquid crystal alignment film is generally made of a polymer such as polyamic acid, polyimide, or polysiloxane, because of its excellent properties such as heat resistance, mechanical strength, and affinity with liquid crystal.

[0003] As the resolution of liquid crystal display elements increases, there are demands for suppressing the decrease in contrast of liquid crystal display elements and reducing the afterimage phenomenon. In addition to excellent liquid crystal alignment properties and stable pretilt angles, liquid crystal alignment films are increasingly required to have properties such as a high voltage holding ratio, suppression of afterimages caused by AC driving, small residual charge when a DC voltage is applied, and / or rapid relaxation of residual charge accumulated by a DC voltage. Various proposals have been made for polyimide-based liquid crystal alignment films to meet the above demands (see Patent Documents 1 to 5). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-316200 [Patent Document 2] Japanese Patent Application Publication No. 10-104633 [Patent Document 3] Japanese Patent Application Publication No. 8-76128 [Patent Document 4] Japanese Patent Application Publication No. 9-138414 [Patent Document 5] Japanese Patent Application Publication No. 11-38415 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent liquid crystal display devices, in order to expand the effective pixel area, there is a demand for increasingly smaller frame areas, which are the peripheral edges of the substrate where no pixels are formed. As panel frames become narrower, the sealant used to bond two substrates together to produce a liquid crystal display device is now applied to a polyimide-based liquid crystal alignment film. However, because polyimides do not have polar groups, covalent bonds cannot be formed between the sealant and the surface of the liquid crystal alignment film, resulting in insufficient adhesion between the substrates. Therefore, improving the adhesion (adhesion) between the polyimide-based liquid crystal alignment film and the sealant or substrates is a challenge. [Means for solving the problem]

[0006] The present inventors have conducted extensive research to solve the above problems, and as a result have found that various properties can be improved simultaneously by introducing a specific structure into a polymer contained in a liquid crystal aligning agent, and have completed the present invention. The present invention is based on this finding and has the following gist. 1. A liquid crystal aligning agent containing a polymer obtained from a diamine represented by the following general formula (1) and an organic solvent. [ka] (In formula (1), T 1 and T 2are each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -N(CH3)-, -CON(CH3)-, or -N(CH3)CO-, and W is a single bond or a divalent organic group (provided that T 1 or T 2 When is a single bond, W is a single bond, and Q represents a substituent represented by the following formula (2). Two Qs in a molecule may be the same or different. [ka] (In formula (2), X is a single bond, -O-, -COO-, -OCO-, or -S-; R 1 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, A is a protecting group that is substituted with a hydrogen atom by heat, and n is an integer of 1 to 6. [Effects of the Invention]

[0007] According to the liquid crystal aligning agent of the present invention, a liquid crystal display element having excellent adhesion (tightness) between a polyimide-based liquid crystal alignment film and a sealing agent or substrate, and a liquid crystal alignment film that provides the same can be obtained.

[0008] The liquid crystal aligning agent of the present invention provides a liquid crystal alignment film with excellent adhesion to a sealant. By using this liquid crystal alignment film, a liquid crystal display device with excellent adhesion between substrates and high shock resistance can be obtained. The mechanism by which adhesion to a sealant is improved is not entirely clear, but it is thought that the presence of a group having an NA structure at a predetermined position on the benzene ring suppresses intramolecular cyclization when an A group is eliminated from the NA group of the diamine and replaced with a hydrogen atom. As a result, the amino group generated by elimination of the protecting group upon heating is exposed on the surface of the liquid crystal alignment film, and the interaction between this group and the functional group in the sealant is thought to improve adhesion between the liquid crystal alignment film and the sealant. DETAILED DESCRIPTION OF THE INVENTION

[0009] The liquid crystal aligning agent of the present invention is a liquid crystal aligning agent containing a polymer (hereinafter also referred to as a specific polymer) obtained from a diamine having a structure (hereinafter also referred to as a specific structure) represented by the above formula (1). Each condition will be described in detail below.

[0010] <Diamines with specific structures> In the above formula (1), T 1 , T 2 , W, and Q have the meanings as described above. In the above formula (1), T 1 and T 2 are preferably each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, or -N(CH3)-, and W is preferably a single bond or a hydrocarbon group having a linear, branched, or cyclic structure. The hydrocarbon group preferably has 1 to 20 carbon atoms, and a portion of the hydrocarbon group may be substituted with -O-, -COO-, or -OCO-. Preferred specific examples of the cyclic structure include a phenylene group and a cyclohexylene group. In the above formula (2), X is preferably any one of a single bond, -O-, -COO-, and -OCO-, and R 1 is preferably a hydrogen atom. A is preferably a tert-butoxycarbonyl group, and n is preferably an integer of 1 to 6. Specific examples of the diamine of the above formula (1) include, but are not limited to, the diamines represented by the following DA-1 to DA-4, in which Boc represents a tert-butoxycarbonyl group. [ka]

[0011] <Polymer> The polymer of the present invention is a polymer obtained using the above diamine. Specific examples include polyamic acid, polyamic acid ester, polyimide, polyurea, polyamide, etc., but from the viewpoint of use as a liquid crystal aligning agent, it is more preferable to use at least one selected from a polyimide precursor having a structural unit represented by the following formula (3) and a polyimide which is an imidized product thereof: [ka] However, X 1 is a tetravalent organic group derived from a tetracarboxylic acid derivative, and Y 1 is a divalent organic group derived from a diamine having a structure represented by the formula (1), and R 2 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 2 is preferably a hydrogen atom, a methyl group, or an ethyl group from the viewpoint of ease of imidization by heating. 2 may be the same or different from each other.

[0012] <Tetracarboxylic acid dianhydride> X1 is a tetravalent organic group derived from a tetracarboxylic acid derivative, and its structure is not particularly limited. X1 in the polyimide precursor is appropriately selected depending on the required properties, such as the solubility of the polymer in a solvent, the coatability of a liquid crystal alignment agent, the alignment of liquid crystals when formed into a liquid crystal alignment film, the voltage holding ratio, and the stored charge. One type of X1 may be present in the same polymer, or two or more types may be present in the same polymer.

[0013] Specific examples of X1 include structures of formulae (X-1) to (X-46) listed in pages 13 and 14 of International Publication No. 2015 / 119168.

[0014] Preferred structures of X1 are shown below, but the present invention is not limited to these. [ka]

[0015] [ka]

[0016] Of the above structures, (A-1) and (A-2) are particularly preferred from the viewpoint of photoalignment, (A-4) is particularly preferred from the viewpoint of further improving the relaxation rate of accumulated charges, and (A-15) to (A-17) are particularly preferred from the viewpoint of further improving the liquid crystal alignment and the relaxation rate of accumulated charges.

[0017] <Polymers (other structural units)> The polyimide precursor having the structural unit represented by formula (3) may further have at least one selected from the structural unit represented by the following formula (4) and its imidized structure, within the range that does not impair the effects of the present invention. [ka] In formula (4), X2 is a tetravalent organic group derived from a tetracarboxylic acid derivative, Y2 is a divalent organic group derived from a diamine that does not contain the structure of formula (1) in the main chain direction, R5 is defined as R2 in formula (3), and R6 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. At least one of the two R6s is preferably a hydrogen atom. The two R5s and R6s may be the same or different from each other.

[0018] Specific examples of X2 include the same structures as those exemplified for X1 in formula (3), including preferred examples. Furthermore, Y2 in the polyimide precursor is a divalent organic group derived from a diamine that does not contain the structure of formula (1) in the main chain direction, and its structure is not particularly limited. Furthermore, Y2 is appropriately selected depending on the required degree of properties, such as the solubility of the polymer in a solvent, the coatability of the liquid crystal alignment agent, the alignment of the liquid crystal when formed into a liquid crystal alignment film, the voltage holding ratio, and the stored charge, and may be one type or two or more types mixed in the same polymer.

[0019] Specific examples of Y2 include the structure of formula (2) described in paragraph 4 of WO 2015 / 119168, and the structures of formulae (Y-1) to (Y-97) and (Y-101) to (Y-118) described in paragraphs 8 to 12; a divalent organic group obtained by removing two amino groups from formula (2) described in paragraph 6 of WO 2013 / 008906; a divalent organic group obtained by removing two amino groups from formula (1) described in paragraph 8 of International Publication No. 2015 / 060360; a divalent organic group obtained by removing two amino groups from formula (1) described in paragraph 8 of Japanese Patent Publication No. 2012-173514; and a divalent organic group obtained by removing two amino groups from formulas (A) to (F) described in paragraph 9 of International Publication No. 2010-050523.

[0020] Preferred structures of Y2 are shown below, but the present invention is not limited to these. [ka]

[0021] [ka]

[0022] [ka]

[0023] [ka]

[0024] Of the above structures, (B-28) and (B-29) are particularly preferred from the viewpoint of further improving film hardness, (B-1) to (B-3) are particularly preferred from the viewpoint of further improving liquid crystal alignment, (B-14) to (B-18) and (B-27) are particularly preferred from the viewpoint of further improving the relaxation rate of accumulated charges, and (B-26) is preferred from the viewpoint of further improving the voltage holding ratio. In (B-28) to (B-30), the two n's may be the same or different.

[0025] <Diamine with specific side chain structure> Also, Y 2 It is also preferable to use a diamine having a specific side chain structure as the diamine. The diamine having a specific side chain structure is represented by, for example, the following formulas [1] and [2]. [ka] In the above formula [2], X is a single bond, -O-, -C(CH3)2-, -NH-, -CO-, -NHCO-, -COO-, -(CH2) m X represents a divalent organic group consisting of -, -SO2-, or any combination thereof. Among these, X represents a single bond, -O-, -NH-, -O-(CH2) m Preferred is -O-. As "any combination thereof", -O-(CH2) m -O-, -OC(CH3)2-, -CO-(CH2) m -, -NH-(CH2) m -, -SO2-(CH2) m -, -CONH-(CH2) m -, -CONH-(CH2) m -NHCO-, -COO-(CH2) m Examples include, but are not limited to, -OCO-, etc. m is an integer of 1 to 8. In the above formulas [1] and [2], Y each independently represents at least one selected from the side chain structures represented by formulas [S1] to [S3]. In the above formula [2], the two Ys may be the same or different. Details of the side chain structures represented by formulas [S1] to [S3] will be described later.

[0026] In addition, in the above formula [2], Y may be in the meta position or the ortho position relative to the position of X, but is preferably in the ortho position. That is, the above formula [2] is preferably the following formula [2']. [ka]

[0027] In addition, in the above formula [2], the positions of the two amino groups (-NH2) may be any positions on the benzene ring, but the positions represented by the following formulas [2]-a1 to [2]-a3 are preferred, and the following formula [2]-a1 is more preferred. In the following formulas, X is the same as in the above formula [2]. Note that the following formulas [2]-a1 to [2]-a3 explain the positions of the two amino groups, and the notation of Y represented in the above formula [2] is omitted.

[0028] [ka]

[0029] Therefore, based on the above formula [2'] and [2]-a1 to [1]-a3, the above formula [2] is preferably any structure selected from the following formulas [2]-a1-1 to [2]-a3-2, and more preferably a structure represented by the following formula [2]-a1-1: In the following formula, X and Y are the same as in formula [2].

[0030] [ka]

[0031] These two-chain diamines represented by the formula [2] can be used alone or in combination of two or more. Depending on the properties required for the liquid crystal alignment film or liquid crystal display element, it is possible to appropriately adjust whether to use one type alone or in combination of two or more types, and when using two or more types in combination, the ratio, etc.

[0032] In the above formulas [1] and [2], Y represents a specific side chain structure selected from the group represented by the following formulas [S1] to [S3]. Hereinafter, such specific side chain structures will be explained in the order of formulas [S1] to [S3].

[0033] An example of the specific side chain structure is a diamine having a specific side chain structure represented by the following formula [S1]. [ka] In the above formula [S1], X 1 and X 2 are each independently a single bond, -(CH2) a -(a is an integer of 1 to 15), -CONH-, -NHCO-, -CON(CH3)-, -NH-, -O-, -COO-, -OCO- or -((CH2) a1 -A1) m1 In this, a plurality of a1's each independently represents an integer of 1 to 15, a plurality of A1's each independently represents an oxygen atom or -COO-, and m1 is 1 or 2.

[0034] Among these, X is the most popular from the viewpoint of raw material availability and ease of synthesis. 1 and X 2 are each independently a single bond, -(CH2) a - (where a is an integer of 1 to 15), -O-, -CHO- or -COO- is preferred. 1 and X 2 are each independently a single bond, -(CH2) a - (where a is an integer of 1 to 10), -O-, -CH2O- or -COO-.

[0035] In addition, in the above formula [S1], G 1 and G 2 each independently represents a divalent cyclic group selected from a divalent aromatic group having 6 to 12 carbon atoms or a divalent alicyclic group having 3 to 8 carbon atoms. Any hydrogen atom on the cyclic group may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkoxyl group having 1 to 3 carbon atoms, a fluorine-containing alkyl group having 1 to 3 carbon atoms, a fluorine-containing alkoxyl group having 1 to 3 carbon atoms, or a fluorine atom. m and n each independently represent an integer of 0 to 3, and the sum of m and n is 1 to 4. X 1 , X 2 , G 1 and G 2 If there are multiple X 1 , X 2 , G 1 and G 2may be the same or different from each other.

[0036] In addition, in the above formula [S1], R 1 represents alkyl having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, or alkoxyalkyl having 2 to 20 carbon atoms, and R 1 Any hydrogen atom forming the group may be substituted with fluorine. Examples of the divalent aromatic group having 6 to 12 carbon atoms include phenylene, biphenylene, and naphthalene. Examples of the divalent alicyclic group having 3 to 8 carbon atoms include cyclopropylene and cyclohexylene.

[0037] Therefore, preferred specific examples of the above formula [S1] include, but are not limited to, the following formulae [S1-x1] to [S1-x7].

[0038] [ka] In the above formulas [S1-x1] to [S1-x7], R 1 is the same as in the above formula [S1]. p is -(CH2) a A1 represents an oxygen atom or -COO-* (the bond marked with "*" is (CH2)) a2 A2 represents an oxygen atom or *-COO- (the bond marked with "*" is (CH2) a2 a1 is an integer of 0 or 1, and a2 is an integer of 2 to 10. Cy, i.e., a group written as "Cy" in a cyclohexane ring, represents a 1,4-cyclohexylene group or a 1,4-phenylene group.

[0039] An example of the specific side chain structure is the specific side chain structure represented by the following formula [S2]. [ka] In the above formula [S2], X 3represents a single bond, -CONH-, -NHCO-, -CON(CH3)-, -NH-, -O-, -CHO-, -COO- or -OCO-. 3 is preferably -CONH-, -NHCO-, -O-, -CHO-, -COO- or -OCO-. 2 represents alkyl having 1 to 20 carbon atoms or alkoxyalkyl having 2 to 20 carbon atoms, and R 2 Any hydrogen atom forming R may be substituted with fluorine. 2 is preferably alkyl having 3 to 20 carbon atoms or alkoxyalkyl having 2 to 20 carbon atoms.

[0040] Further, an example of the specific side chain structure is the specific side chain structure represented by the following formula [S3]. [ka] In the above formula [S3], X 4 represents -CONH-, -NHCO-, -O-, -COO- or -OCO-. 3 represents a structure having a steroid skeleton. The steroid skeleton here has a skeleton represented by the following formula (st) in which three six-membered rings and one five-membered ring are bonded.

[0041] [ka]

[0042] An example of the above formula [S3] is the following formula [S3-x], but is not limited thereto. [ka] In the formula [S3-x], X represents the formula [X1] or [X2]. Col represents a group selected from the group consisting of the formulae [Col1] to [Col3], and G represents a group selected from the group consisting of the formulae [G1] to [G4]. * represents a bonding site to another group.

[0043] Examples of preferred combinations of X, Col and G in the above formula [S3-x] include a combination of formula [X1] with formulas [Col1] and [G2], a combination of formula [X1] with formulas [Col2] and [G2], a combination of formula [X2] with formulas [Col1] and [G2], a combination of formula [X2] with formulas [Col2] and [G2], and a combination of formula [X1] with formulas [Col3] and [G1].

[0044] Specific examples of the formula [S3] include a structure obtained by removing a hydroxyl group (hydroxy group) from a steroid compound described in paragraph

[0024] of JP-A-4-281427, a structure obtained by removing an acid chloride group from a steroid compound described in paragraph

[0030] of the same publication, a structure obtained by removing an amino group from a steroid compound described in paragraph

[0038] of the same publication, a structure obtained by removing a halogen group from a steroid compound described in paragraph

[0042] of the same publication, and structures described in paragraphs

[0018] to

[0022] of JP-A-8-146421.

[0045] These diamines having specific side chain structures represented by the above formulae [S1] to [S3] can be used alone or in combination of two or more. Depending on the properties required for the liquid crystal alignment film or liquid crystal display element, it is possible to appropriately adjust whether to use one type alone or in combination of two or more types, and when using two or more types in combination, the ratio, etc.

[0046] Among these, examples of diamines having a side chain structure selected from the group represented by the above formulas [S1] to [S3] include diamines having structures of the following formulas [1-S1] to [1-S3] and [2-S1] to [1-S3], respectively. [ka]

[0047] In the above formulas [1-S1] and [2-S1], X 1 , X 2 , G 1 , G 2 , R 1 , m and n are the same as in the above formula [S1]. In the above formula [1-S2], X 3and R 2 is the same as in the above formula [S2]. In the above formula [1-S3], X 4 and R 3 is the same as in the above formula [S3]. In the above formulas [1-S1] and [2-S1] to [2-S3], X 1 , X 2 , G 1 , G 2 , X 3 , R 2 , X 4 , R 3 , m and n are multiple, there are multiple X 1 , X 2 , G 1 , G 2 , X 3 , R 2 , X 4 , R 3 , m and n may be the same or different from each other.

[0048] Among these, examples of the diamines represented by the above formulas [1-S1] to [1-S3] include, but are not limited to, the specific structures shown below. [ka]

[0049] Examples of diamines represented by the above formulas [2-S1] to [2-S3] include, but are not limited to, the specific structures shown below. [ka]

[0050] <Other diamines: diamines with photoreactive side chains> Also, Y 2 It is also preferable to use a diamine having a photoreactive side chain as the diamine component. When the diamine component contains a diamine having a photoreactive side chain, it becomes possible to introduce a photoreactive side chain into the specific polymer or other polymers.

[0051] Examples of diamines having a photoreactive side chain include, but are not limited to, those represented by the following formula [VIII] or [IX]. [ka]

[0052] [ka]

[0053] In the above formulas [VIII] and [IX], the positions of the two amino groups (-NH2) may be any positions on the benzene ring, for example, the 2,3 positions, the 2,4 positions, the 2,5 positions, the 2,6 positions, the 3,4 positions, or the 3,5 positions on the benzene ring relative to the bonding group of the side chain. From the viewpoint of reactivity in synthesizing a polyamic acid, the 2,4 positions, the 2,5 positions, or the 3,5 positions are preferred. Taking into consideration the ease of synthesizing a diamine, the 2,4 positions or the 3,5 positions are more preferred.

[0054] In addition, in the above formula [VIII], R 8 represents a single bond, -CH2-, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CHO-, -N(CH3)-, -CON(CH3)- or -N(CH3)CO-. In particular, R 8 is preferably a single bond, —O—, —COO—, —NHCO— or —CONH—.

[0055] In addition, in the above formula [VIII], R 9 represents a single bond or an alkylene group having 1 to 20 carbon atoms which may be substituted with a fluorine atom. Here, -CH2- in the alkylene group may be optionally substituted with -CF2- or -CH=CH-, and may be substituted with any of the following groups when they are not adjacent to each other: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, or a divalent carbocyclic or heterocyclic ring.

[0056] Of the above, specific examples of the divalent carbocyclic or heterocyclic ring include, but are not limited to, structures selected from the following formula (1a): [ka]

[0057] In addition, in the above formula [VIII], R 9 can be formed by a common organic synthesis method, but from the viewpoint of ease of synthesis, a single bond or an alkylene group having 1 to 12 carbon atoms is preferred.

[0058] In addition, in the above formula [VIII], R 10 represents a photoreactive group selected from the group consisting of the following formula (1b): 10 In terms of photoreactivity, a methacrylic group, an acrylic group, or a vinyl group is preferred. [ka]

[0059] In the formula [IX], Y1 represents -CH2-, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO-. Y2 represents an alkylene group having 1 to 30 carbon atoms, or a divalent carbocyclic or heterocyclic ring. One or more hydrogen atoms in the alkylene group, divalent carbocyclic or heterocyclic ring may be substituted with a fluorine atom or an organic group. When Y2 is one of the following groups that are not adjacent to each other, -CH2- may be substituted with these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, or -CO-. Examples of the organic group include a substituent selected from the group consisting of a halogen atom-containing alkyl group, a halogen atom-containing alkoxy group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, and a heteroatom-containing group in which a carbon-carbon bond in any methylene group of the halogen atom-containing alkyl group, halogen atom-containing alkoxy group, alkyl group, alkoxy group, and alkenyl group is interrupted by an oxygen atom.

[0060] In the formula [IX], Y3 represents -CH2-, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO-, or a single bond. Y4 represents a cinnamoyl group. Y5 represents a single bond, an alkylene group having 1 to 30 carbon atoms, or a divalent carbocyclic or heterocyclic ring. One or more hydrogen atoms in the alkylene group, divalent carbocyclic or heterocyclic ring may be substituted with a fluorine atom or an organic group. When Y5 is not adjacent to any of the following groups, -CH2- may be substituted with these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, or -CO-. Y6 represents a photopolymerizable group such as an acrylic group or a methacrylic group. Examples of the organic group include a substituent selected from the group consisting of a halogen atom-containing alkyl group, a halogen atom-containing alkoxy group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 1 to 10 carbon atoms, and a heteroatom-containing group in which a carbon-carbon bond in any methylene group of the halogen atom-containing alkyl group, halogen atom-containing alkoxy group, alkyl group, alkoxy group, and alkenyl group is interrupted by an oxygen atom.

[0061] Specific examples of such diamines having a photoreactive side chain represented by the above formula [VIII] or [IX] include, but are not limited to, diamines selected from the following formula (1c): [ka] In the above formula (1c), X 9 and X 10 each independently represents a single bond, -O-, -COO-, -NHCO- or -NH-. Y represents an alkylene group having 1 to 20 carbon atoms which may be substituted with a fluorine atom.

[0062] Diamines having a photoreactive side chain include those of the following formula [VII]. The diamine of formula [VII] has a moiety having a radical-generating structure in the side chain. The radical-generating structure decomposes upon exposure to ultraviolet light to generate radicals. [ka] In the above formula [VII], Ar represents at least one aromatic hydrocarbon group selected from the group consisting of phenylene, naphthylene, and biphenylene, and a hydrogen atom of the aromatic hydrocarbon group may be substituted with a halogen atom. Since Ar having a carbonyl bond is involved in the absorption wavelength of ultraviolet light, a structure with a long conjugation length, such as naphthylene or biphenylene, is preferred for increasing the wavelength. On the other hand, when Ar has a structure such as naphthylene or biphenylene, solubility may be reduced, making synthesis more difficult. Since a phenyl group can provide sufficient properties when the ultraviolet light wavelength is in the range of 250 nm to 380 nm, a phenyl group is most preferred for Ar.

[0063] In the above Ar, the aromatic hydrocarbon group may have a substituent other than a halogen atom, and examples of the substituent here include preferably an electron-donating organic group such as an alkyl group, a hydroxyl group, an alkoxy group, or an amino group.

[0064] In the formula [VII], R1 and R2 each independently represent an alkyl group, an alkoxy group, a benzyl group, or a phenethyl group having 1 to 10 carbon atoms. In the case of an alkyl group or an alkoxy group, R1 and R2 may form a ring.

[0065] In the above formula [VII], T1 and T2 each independently represent a single bond, or a bonding group such as -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CHO-, -N(CH)-, -CON(CH)-, or -N(CH)CO-.

[0066] In formula [VII], S represents a single bond or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms. Here, -CH2- or -CF2- in the alkylene group may be optionally substituted with -CH=CH-, and may be substituted with any of the following groups when they are not adjacent to each other: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic ring, or a divalent heterocyclic ring.

[0067] In addition, in the formula [VII], Q represents a structure selected from the following formula (1d). [ka] In the above formula (1d), R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. R represents -CH2-, -NR-, -O-, or -S-. The two Rs may be the same or different.

[0068] In the formula [VII], Q is preferably an electron-donating organic group, and is preferably a hydroxy group, an alkoxy group, an amino group, etc., as mentioned in the examples of Ar above. When Q is an amino derivative, there is a possibility that a carboxylic acid group generated during polymerization of a polyamic acid, which is a precursor of a polyimide, and an amino group may form a salt, and thus a hydroxy group or an alkoxy group is more preferred.

[0069] In addition, in the above formula [VII], the positions of the two amino groups (—NH2) may be any of o-phenylenediamine, m-phenylenediamine, and p-phenylenediamine, but m-phenylenediamine and p-phenylenediamine are preferred in terms of reactivity with acid dianhydrides.

[0070] Therefore, the following formula is a preferred specific example of the above formula [VII] in terms of ease of synthesis, versatility, properties, etc. In the following formula, n is an integer of 2 to 8. [ka]

[0071] These diamines having photoreactive side chains represented by the above formula [VII], [VIII], or [IX] can be used alone or in combination of two or more. Whether they are used alone or in combination of two or more, and when two or more are used in combination, the ratio, etc., can be appropriately adjusted depending on the liquid crystal alignment property, pretilt angle, voltage retention characteristic, stored charge, and other characteristics when used as a liquid crystal alignment film, and the response speed of the liquid crystal when used as a liquid crystal display element.

[0072] When a polyimide precursor having a structural unit represented by formula (3) also has a structural unit represented by formula (4), the structural unit represented by formula (3) preferably accounts for 10 mol % or more, more preferably 15 mol % or more, and particularly preferably 20 mol % or more of the total of formulas (3) and (4).

[0073] The molecular weight of the polyimide precursor used in the present invention is preferably 2,000 to 500,000, more preferably 5,000 to 300,000, and even more preferably 10,000 to 100,000, in terms of weight average molecular weight.

[0074] The polyimide having the divalent group represented by formula (1) in the main chain may be obtained by ring-closing the polyimide precursor. In this polyimide, the ring-closure rate of the amic acid group (also called the imidization rate) does not necessarily need to be 100% and can be adjusted as desired depending on the application or purpose. 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.

[0075] The liquid crystal aligning agent of the present invention is a composition containing the above-mentioned specific polymer and an organic solvent, and may contain two or more specific polymers having different structures. Furthermore, the liquid crystal aligning agent of the present invention may contain a polymer other than the specific polymer (hereinafter also referred to as a second polymer) and various additives to the extent that the effects described in the present invention are exhibited.

[0076] When the liquid crystal aligning agent of the present invention contains a second polymer, the ratio of the specific polymer to the total polymer components is preferably 5% by mass or more, and an example thereof is 5 to 95% by mass.

[0077] Examples of the second polymer include polyamic acid, polyimide, polyamic acid ester, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene or its derivative, poly(styrene-phenylmaleimide) derivative, and poly(meth)acrylate.

[0078] In particular, a polyamic acid obtained from a tetracarboxylic dianhydride component and a diamine component (hereinafter also referred to as a second polyamic acid) is preferable as the second polymer.

[0079] An example of a tetracarboxylic dianhydride component for obtaining the second polyamic acid is a compound represented by the following formula (11): The dianhydride component may be composed of one type of compound or two or more types of compounds. [ka] In formula (11), A is a tetravalent organic group, preferably a tetravalent organic group having 4 to 30 carbon atoms.

[0080] Specific examples of A include the same structures as those exemplified for X1 in formula (3), including preferred examples.

[0081] The diamine component for obtaining the second polyamic acid can be appropriately determined depending on the purpose, and for example, a diamine represented by the following formula (12) can be used. [ka] (Y9 represents a divalent organic group. A9 are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkynyl group having 2 to 5 carbon atoms, and may be the same or different. From the viewpoint of liquid crystal alignment, A9 is preferably a hydrogen atom or a methyl group.)

[0082] The structures of Y9 in formula (12), which are preferably used as the diamine component for obtaining the second polyamic acid, are shown below, but the present invention is not limited to these. [ka]

[0083] For the purpose of improving electrical properties and relaxation properties, Y9 is preferably a divalent organic group having a tertiary nitrogen atom or a divalent organic group having -NH-CO-NH- in the molecule. Specific examples of formula (12) when Y9 is a divalent organic group having a tertiary nitrogen atom include diamines having a pyrrole structure described in International Publication WO2017 / 126627, preferably diamines having a structure represented by the following formula (pr):

[0084] [ka] (R 1 represents a hydrogen atom, hydrogen, a fluorine atom, a cyano group, a hydroxyl group, or a methyl group, and R 2 are each independently a single bond or a group "*1-R 3 -Ph-*2" and R 3 is a single bond, -O-, -COO-, -OCO-, -(CH2) l -, -O(CH2) m represents a divalent organic group selected from -O-, -CONH-, and -NHCO- (l and m represent integers of 1 to 5), *1 represents the site of bonding to the benzene ring in formula (pr), *2 represents the site of bonding to the amino group in formula (pr). Ph represents a phenylene group. n represents 1 to 3. R 1 and R 2 If there are two or more, there are two or more R 1 and R 2may be the same or different from each other.), a diamine having a pyrrole structure described in International Publication WO2018 / 062197, preferably a diamine having a structure represented by the following formula (pn):

[0085] [ka] (R 1 and R 2 each independently represents a hydrogen atom or a methyl group, R 3 is a single bond or a group "*1-R 4 -Ph-*2" and R 4 is a single bond, -O-, -COO-, -OCO-, -(CH2) l -, -O(CH2) m represents a divalent organic group selected from -O-, -CONH-, and -NHCO- (l and m represent integers of 1 to 5), *1 represents the site of bonding to the benzene ring in formula (pn), *2 represents the site of bonding to the amino group in formula (pn), Ph represents a phenylene group, and n represents 1 to 3. R 1 , R 2 and R 3 If there are two or more, there are two or more R 1 , R 2 and R 3 may be the same or different from each other.), a diamine having a carbazole structure described in International Publication WO2018 / 110354, preferably a diamine having a structure represented by the following formula (cz):

[0086] [ka] (R 1 represents a hydrogen atom or a methyl group, and R 2 represents a methyl group), diamines having a nitrogen-containing heterocycle described in paragraphs

[0173] to

[0188] of International Publication WO2015 / 046374, diamines having a nitrogen-containing structure described in paragraph

[0050] of JP2016-218149A, and diamines represented by the following formula (BP):

[0087] [ka] (X is a biphenyl ring or a fluorene ring; Y is a benzene ring, a biphenyl ring, or a group selected from -phenylene-Z-phenylene-; Z is a divalent group represented by -O-, -NH-, -CH2-, -SO2-, -C(CH3)2-, or -C(CF3)2-; A and B each independently represent a hydrogen atom or a methyl group), 2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, Lysine, 2,4-diaminopyrimidine, 5,6-diamino-2,3-dicyanopyrazine, 5,6-diamino-2,4-dihydroxypyrimidine, 2,4-diamino-6-dimethylamino-1,3,5-triazine, 1,4-bis(3-aminopropyl)piperazine, 4,4'-[4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)]dianiline, 2,4-diamino-6-isopropoxy-1 ,3,5-triazine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4-diamino-6-phenyl-1,3,5-triazine, 2,4-diamino-6-methyl-s-triazine, 2,4-diamino-1,3,5-triazine, 4,6-diamino-2-vinyl-s-triazine, 3,5-diamino-1,2,4-triazole, 6,9-diamino-2-ethoxyacridine lactate, 3,8- Examples thereof include diamino-6-phenylphenanthridine, 1,4-diaminopiperazine, 3,6-diaminoacridine, bis(4-aminophenyl)phenylamine, 4,4'-diphenylmethylamine, 4,4'-diphenylamine, 3,6-diaminocarbazole, 9-methyl-3,6-diaminocarbazole, 9-ethyl-3,6-diaminocarbazole, and diamines represented by the following formulas (w1) to (w2).

[0088] [ka] (Sp represents phenylene, pyrrolidine, piperidine, piperazine, a divalent chain hydrocarbon group having 2 to 20 carbon atoms, or a group in which -CH2- of the divalent chain hydrocarbon group has been substituted with a group selected from -O-, -CO-, -CO-O-, -NRCO- (R represents a hydrogen atom or a methyl group), -NRCOO- (R represents a hydrogen atom or a methyl group), -CONR- (R represents a hydrogen atom or a methyl group), -COS-, -NR- (R represents a methyl group), pyrrolidine, piperidine, and piperazine.)

[0089] Specific examples of formula (12) in which Y9 in formula (12) is a divalent organic group having -NH-CO-NH- in the molecule include diamines in which A1 in the above formula (4) is -NH-CO-NH-, a group in which at least one -CH2- in a chain hydrocarbon group having 2 to 20 carbon atoms is substituted with -NH-CO-NH-, or a group in which at least one -CH2- in a chain hydrocarbon group having 2 to 20 carbon atoms is substituted with -NH-CO-NH- and at least one other -CH2- is substituted with a group selected from -O-, -CO-, -CO-O-, -NRCO- (R represents a hydrogen atom or a methyl group), -NRCOO- (R represents a hydrogen atom or a methyl group), -CONR- (R represents a hydrogen atom or a methyl group), -COS-, and -NR- (R represents a methyl group). More preferred specific examples of diamines include diamines represented by the following formulas (U-1) to (U-9). [ka]

[0090] Preferred specific examples of the diamines represented by the above formulas (w1) and (w2) include diamines represented by the following formulas (n3-1) to (n3-7) and diamines represented by the following formulas (n4-1) to (n4-6). [ka]

[0091] [ka]

[0092] To improve printability, diamine compounds having a carboxy group (-COOH group) or a hydroxy group (-OH group) can also be used. Specific examples include 2,4-diaminophenol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, and 3,5-diaminobenzoic acid. Among these, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, and 3,5-diaminobenzoic acid are preferred. Diamine compounds represented by the following formulas [3b-1] to [3b-4] and diamine compounds in which the amino group is a secondary amino group can also be used.

[0093] [ka] (In formula [3b-1], Q 1 represents a single bond, -CH2-, -C2H4-, -C(CH3)2-, -CF2-, -C(CF3)2-, -O-, -CO-, -NH-, -N(CH3)-, -CONH-, -NHCO-, -C2O-, -OCH2-, -COO-, -OCO-, -CON(CH3)- or -N(CH3)CO-; m1 and m2 each independently represent an integer of 0 to 4, and m1 + m2 represents an integer of 1 to 4; in formula [3b-2], m3 and m4 each independently represent an integer of 1 to 5; in formula [3b-3], Q 2 represents a linear or branched alkyl group having 1 to 5 carbon atoms, m5 represents an integer of 1 to 5, and in formula [3b-4], Q 3 and Q 4 each independently represents a single bond, -CH2-, -C2H4-, -C(CH3)2-, -CF2-, -C(CF3)2-, -O-, -CO-, -NH-, -N(CH3)-, -CONH-, -NHCO-, -C2O-, -OCH2-, -COO-, -OCO-, -CON(CH3)- or -N(CH3)CO-, and m6 represents an integer of 1 to 4.

[0094] The diamine component for obtaining the second polyamic acid may be, in addition to the above, the diamine used in the specific polymer or a known diamine, but the present invention is not limited thereto. The diamine component for obtaining the second polyamic acid may be one type of diamine, or two or more types of diamines may be used in combination.

[0095] <Methods of producing polyamic acid, polyamic acid ester, and polyimide> The polyimide precursors used in the present invention, that is, polyamic acid ester, polyamic acid, and polyimide, can be synthesized by known methods such as those described in International Publication WO2013 / 157586.

[0096] <Liquid crystal alignment agent> The liquid crystal aligning agent of the present invention contains a specific polymer. The liquid crystal aligning agent of the present invention may contain other polymers in addition to the specific polymer and, if desired, a second polymer. Examples of the other polymers include polyamic acid, polyimide, polyamic acid ester, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivatives, polyacetal, polystyrene or its derivatives, poly(styrene-phenylmaleimide) derivatives, and poly(meth)acrylate.

[0097] The liquid crystal aligning agent is used to prepare a liquid crystal alignment film, and is in the form of a coating liquid from the viewpoint of forming a uniform thin film. The liquid crystal aligning agent of the present invention is also preferably a coating liquid containing a polymer component containing a specific polymer and an organic solvent. In this case, the concentration of the polymer in the liquid crystal aligning agent can be appropriately changed depending on the thickness of the coating film to be formed. From the viewpoint of forming a uniform, defect-free coating film, the concentration is preferably 1% by mass or more, and from the viewpoint of the storage stability of the solution, the concentration is preferably 10% by mass or less. A particularly preferred polymer concentration is 2 to 8% by mass.

[0098] The organic solvent contained in the liquid crystal aligning agent is not particularly limited as long as it can uniformly dissolve the polymer component. Specific examples include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, and 3-butoxy-N,N-dimethylpropanamide (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 good solvent in the liquid crystal aligning agent of the present invention preferably accounts for 20 to 99 mass %, more preferably 20 to 90 mass %, and particularly preferably 30 to 80 mass %, of the total solvent contained in the liquid crystal aligning agent.

[0099] In addition, the organic solvent contained in the liquid crystal aligning agent is preferably a mixed solvent containing, in addition to the above-mentioned solvent, a solvent (also called a poor solvent) that improves the coating property when coating the liquid crystal aligning agent and the surface smoothness of the coating film. Specific examples of the organic solvent to be used in combination are listed below, but are not limited to these examples. For example, 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-butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ethyl ether, diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 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 monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxy)-2-propanol, Examples of the alkyl esters include (2-ethoxy)-1-propanol, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, ethylene glycol monoacetate, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy)ethyl acetate, diethylene glycol acetate, propylene glycol diacetate, n-butyl acetate, propylene glycol monoethyl ether 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, and diisobutyl ketone (2,6-dimethyl-4-heptanone).

[0100] Of these, it is preferable to use 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, and diisobutyl ketone.

[0101] 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-methyl-2-pyrrolidone, γ-butyrolactone, 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, and N-methyl-2-pyrrolidone and γ-butyrolactone. Examples of poor solvents include N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and 2,6-dimethyl-4-heptanone; N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and diisopropyl ether; N-methyl-2-pyrrolidone, γ-butyrolactone, propylene glycol monobutyl ether, and 2,6-dimethyl-4-heptanol; N-methyl-2-pyrrolidone, γ-butyrolactone, and dipropylene glycol dimethyl ether; and N-methyl-2-pyrrolidone, propylene glycol monobutyl ether, and dipropylene glycol dimethyl ether. These poor solvents preferably account for 1 to 80 mass % of the total solvent contained in the liquid crystal aligning agent, more preferably 10 to 80 mass %, and particularly preferably 20 to 70 mass %. The type and content of such solvents are appropriately selected depending on the coating device, coating conditions, and coating environment of the liquid crystal aligning agent.

[0102] The liquid crystal aligning agent of the present invention may additionally contain components other than the polymer component and the organic solvent. Such additional components include an adhesion aid for improving the adhesion between the liquid crystal alignment film and the substrate or between the liquid crystal alignment film and the sealant, a compound for increasing the strength of the liquid crystal alignment film (hereinafter also referred to as a crosslinking compound), a dielectric or conductive substance for adjusting the dielectric constant or electrical resistance of the liquid crystal alignment film, etc.

[0103] As the crosslinkable compound, from the viewpoints of generating less AC afterimages and having a high effect of improving film strength, a compound having at least one group selected from the group consisting of an oxiranyl group, an oxetanyl group, a protected isocyanate group, a protected isothiocyanate group, a group containing an oxazoline ring structure, a group containing a Meldrum's acid structure, a cyclocarbonate group, and a group represented by the following formula (d), or a compound selected from compounds represented by the following formula (e) (hereinafter, these are also collectively referred to as compound (C)). [ka] (In formula (d), R2 and R3 each independently represent a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH2-OH". * represents a bond. In formula (e), A represents an (m+n)-valent organic group having an aromatic ring, R and R' represent a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, m represents an integer of 1 to 6, and n represents an integer of 0 to 4. Any hydrogen atom in the aromatic ring may be replaced with 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, or a fluoroalkoxy group having 1 to 10 carbon atoms.)

[0104] Specific examples of compounds having an oxiranyl group include compounds having two or more oxiranyl groups, such as the compounds described in paragraph

[0037] of JP-A-10-338880 and compounds having a triazine ring skeleton described in International Publication WO 2017 / 170483. Among these, particularly preferred are compounds containing nitrogen atoms, such as N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-p-phenylenediamine, and compounds represented by the following formulas (r-1) to (r-3): [ka]

[0105] Specific examples of the compound having an oxetanyl group include compounds having two or more oxetanyl groups described in paragraphs

[0170] to

[0175] of International Publication No. 2011 / 132751.

[0106] Specific examples of compounds having a protected isocyanate group include compounds having two or more protected isocyanate groups described in paragraphs

[0046] to

[0047] of JP 2014-224978 A, and compounds having three or more protected isocyanate groups described in paragraphs

[0119] to

[0120] of WO 2015 / 141598. Among these, compounds represented by the following formulae (bi-1) to (bi-3) are preferred. [ka]

[0107] Specific examples of compounds having a protected isothiocyanate group include compounds having two or more protected isothiocyanate groups, as described in JP-A-2016-200798.

[0108] Specific examples of compounds having a group containing an oxazoline ring structure include compounds containing two or more oxazoline structures described in paragraph

[0115] of JP-A No. 2007-286597.

[0109] Specific examples of compounds having a group containing a Meldrum's acid structure include compounds having two or more Meldrum's acid structures, as described in International Publication WO2012 / 091088.

[0110] Specific examples of compounds having a cyclocarbonate group include compounds described in International Publication WO2011 / 155577.

[0111] Examples of the alkyl group having 1 to 3 carbon atoms for R2 and R3 in the group represented by formula (d) include the groups exemplified in formulas (l) and (n) above.

[0112] Specific examples of compounds having a group represented by formula (d) include compounds having two or more groups represented by formula (d) described in International Publication WO2015 / 072554 and paragraph

[0058] of JP2016-118753A, compounds described in JP2016-200798A, etc. Among these, compounds represented by the following formulae (hd-1) to (hd-8) are preferred. [ka]

[0113] Examples of the (m+n)-valent organic group having an aromatic ring for A in formula (e) include an (m+n)-valent aromatic hydrocarbon group having 5 to 30 carbon atoms, an (m+n)-valent organic group to which an aromatic hydrocarbon group having 5 to 30 carbon atoms is bonded directly or via a linking group, and an (m+n)-valent group having an aromatic heterocycle. Examples of the aromatic hydrocarbon group include benzene and naphthalene. Examples of the aromatic heterocycle include a pyrrole ring, an imidazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a quinoline ring, an isoquinoline ring, a carbazole ring, a pyridazine ring, a pyrazine ring, a benzimidazole ring, a benzimidazole ring, an indole ring, a quinoxaline ring, and an acridine ring. Examples of the linking group include an alkylene group having 1 to 10 carbon atoms, a group obtained by removing one hydrogen atom from the alkylene group, and a divalent or trivalent cyclohexane ring. Any hydrogen atom in the alkylene group may be substituted with a fluorine atom or an organic group such as a trifluoromethyl group. Specific examples include compounds described in International Publication WO2010 / 074269. Preferred specific examples include the following formulae (e-1) to (e-10): [ka]

[0114] The above compounds are examples of crosslinkable compounds, and the present invention is not limited thereto. For example, components other than those described above are disclosed on pages 53

[0105] to 55

[0116] of International Publication No. 2015 / 060357. The crosslinkable compound contained in the liquid crystal aligning agent of the present invention may be one type, or two or more types may be combined. The content of the crosslinkable compound in the liquid crystal aligning agent of the present invention is preferably 0.5 to 20 parts by mass relative to 100 parts by mass of the polymer component contained in the liquid crystal aligning agent, and more preferably 1 to 15 parts by mass from the viewpoint of promoting the crosslinking reaction to exhibit the desired effect and minimizing the occurrence of AC afterimages.

[0115] Examples of the adhesion aid 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, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, and N-trimethoxysilylpropyltriethoxysilane. Triethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis(oxyethylene)-3-aminopropyltrimethoxysilane, N-bis(oxyethylene)-3-aminopropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,Examples of silane coupling agents include 4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-isocyanatepropyltriethoxysilane. When using these silane coupling agents, the amount 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, from the viewpoint of reducing the occurrence of AC afterimages.

[0116] <Liquid crystal alignment film / LCD element> A liquid crystal alignment film can be produced by using the liquid crystal aligning agent. A liquid crystal display element according to the present invention includes a liquid crystal alignment film formed using the liquid crystal aligning agent. The operation mode of the liquid crystal display element according to the present invention is not particularly limited, and it can be applied to various operation modes, such as TN (Twisted Nematic) type, STN type, vertical alignment type (including VA-MVA type, VA-PVA type, etc.), in-plane switching type (IPS type), FFS (Fringe Field Switching) type, and optically compensated bend type (OCB type).

[0117] The liquid crystal display element according to the present invention can be manufactured by, for example, the following steps (1-1) to (1-3). In step (1-1), different substrates are used depending on the desired operation mode. Steps (1-2) and (1-3) are common to all operation modes.

[0118] [Step (1-1): Formation of coating film] First, the liquid crystal aligning agent of the present invention is applied onto a substrate, and then the coated surface is heated to form a coating film on the substrate.

[0119] (1-1A) For example, when fabricating a TN-type, STN-type, or VA-type liquid crystal display device, first, two substrates each having a patterned transparent conductive film are used as a pair. The liquid crystal alignment agent prepared above is applied to the surface of each substrate, preferably by offset printing, spin coating, roll coating, or inkjet printing. Examples of suitable substrates include glass substrates such as float glass and soda glass; and transparent substrates made of plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly(alicyclic olefin). Examples of suitable transparent conductive films to be applied to one side of the substrate include NESA films (registered trademark of PPG, Inc., USA) made of tin oxide (SnO), and ITO films made of indium oxide-tin oxide (InO-SnO). Patterned transparent conductive films can be obtained by, for example, forming an unpatterned transparent conductive film followed by photoetching to form a pattern; or by using a mask with the desired pattern when forming the transparent conductive film. When applying the liquid crystal alignment agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film, the surface of the substrate on which the coating film is to be formed may be subjected to a pretreatment in which a functional silane compound, a functional titanium compound, or the like is applied in advance.

[0120] After applying the liquid crystal aligning agent, preheating (prebaking) is preferably performed to prevent dripping of the applied liquid crystal aligning agent. The prebaking temperature is preferably 30 to 200°C, more preferably 40 to 150°C, and particularly preferably 40 to 100°C. The prebaking time is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes. Thereafter, the solvent is completely removed, and a baking (postbaking) step is performed, if necessary, to thermally imidize the amic acid structure present in the polymer. The baking temperature (postbaking temperature) at this time is preferably 80 to 300°C, more preferably 120 to 250°C. The postbaking time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The film thickness of the film thus formed is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

[0121] (1-1B) When manufacturing an IPS or FFS liquid crystal display element, a liquid crystal alignment agent is applied to the electrode-forming surface of a substrate having an electrode made of a comb-tooth-patterned transparent conductive film or metal film and to one surface of an opposing substrate having no electrode, and then each coated surface is heated to form a coating film. The materials of the substrate and transparent conductive film used, the coating method, the heating conditions after coating, the method for patterning the transparent conductive film or metal film, the pretreatment of the substrate, and the preferred thickness of the coating film are the same as those described above in (1-1A). The metal film can be, for example, a film made of a metal such as chromium.

[0122] In both of the above cases (1-1A) and (1-1B), a liquid crystal alignment film or a coating film that will become a liquid crystal alignment film is formed by applying the liquid crystal alignment agent to a substrate and then removing the organic solvent. At this time, the coating film may be further heated after formation to promote a dehydration ring-closing reaction of the polyamic acid, polyamic acid ester, and polyimide blended in the liquid crystal alignment agent according to the present invention, thereby forming a more imidized coating film.

[0123] [Step (1-2): Treatment for providing alignment ability] When manufacturing a TN-type, STN-type, IPS-type, or FFS-type liquid crystal display element, the coating film formed in the above step (1-1) is subjected to a treatment to impart liquid crystal alignment ability. This imparts the ability to align liquid crystal molecules to the coating film, turning it into a liquid crystal alignment film. Examples of treatments to impart alignment ability include a rubbing treatment in which the coating film is rubbed in a certain direction with a roll wrapped with a cloth made of fibers such as nylon, rayon, or cotton, and a photoalignment treatment in which the coating film is irradiated with polarized or unpolarized radiation. On the other hand, when manufacturing a VA-type liquid crystal display element, the coating film formed in the above step (1-1) can be used as a liquid crystal alignment film as is, or the coating film may be subjected to an alignment ability imparting treatment.

[0124] When imparting liquid crystal alignment ability to a coating film by photoalignment treatment, the radiation to be irradiated to the coating film can be, for example, ultraviolet light and visible light containing light with a wavelength of 150 to 800 nm. When the radiation is polarized, it may be linearly polarized or partially polarized. Furthermore, when the radiation used is linearly polarized or partially polarized, the radiation may be applied from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these. When irradiating with unpolarized radiation, the radiation is applied from an oblique direction.

[0125] Examples of light sources that can be used include low-pressure mercury lamps, high-pressure mercury lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, and excimer lasers. Ultraviolet light in a preferred wavelength range can be obtained by using a light source in combination with, for example, a filter, a diffraction grating, etc. The radiation dose is preferably 10 to 5,000 mJ / cm. 2 and more preferably 30 to 2,000 mJ / cm 2 is.

[0126] The coating film may be irradiated with light while being heated to enhance reactivity. The temperature during heating is usually 30 to 250°C, preferably 40 to 200°C, and more preferably 50 to 150°C.

[0127] Furthermore, when ultraviolet light containing light with a wavelength of 150 to 800 nm is used, the photo-irradiated film obtained in the above process can be used as a liquid crystal alignment film as is, but the photo-irradiated film may also be baked, washed with water or an organic solvent, or a combination of these. The baking temperature in this case is preferably 80 to 300°C, more preferably 80 to 250°C. The baking time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The baking may be performed once or twice or more times. The photo-alignment treatment here corresponds to a treatment of light irradiation in a state where the film is not in contact with the liquid crystal layer.

[0128] The organic solvent used for the washing is not particularly limited, but specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, and cyclohexyl acetate.

[0129] The rubbing treatment may be followed by further treatments such as irradiating a portion of the liquid crystal alignment film with ultraviolet light to change the pretilt angle of a portion of the liquid crystal alignment film, or by forming a resist film on a portion of the liquid crystal alignment film surface, rubbing the film in a direction different from the previous rubbing treatment, and then removing the resist film, so that the liquid crystal alignment film has different liquid crystal alignment capabilities in different regions. In these cases, the visibility of the resulting liquid crystal display element can be improved. Liquid crystal alignment films suitable for VA-type liquid crystal display elements can also be used suitably for PSA (polymer sustained alignment)-type liquid crystal display elements.

[0130] [Step (1-3): Construction of Liquid Crystal Cell] (1-3A) Two substrates with liquid crystal alignment films formed thereon are prepared as described above, and a liquid crystal cell is fabricated by disposing a liquid crystal between the two substrates facing each other. There are two methods for fabricating a liquid crystal cell, for example. The first method is a conventionally known method. First, the two substrates are placed facing each other with a gap (cell gap) between them so that their liquid crystal alignment films face each other. The peripheries of the two substrates are bonded together with a sealant. Liquid crystal is injected into the substrate surfaces and the cell gap defined by the sealant, and the injection hole is then sealed to fabricate a liquid crystal cell. The second method is a technique called the ODF (One Drop Fill) method. A UV-curable sealant, for example, is applied to a predetermined location on one of the two substrates with a liquid crystal alignment film. Liquid crystal is then dropped onto several predetermined locations on the liquid crystal alignment film surface. The other substrate is then bonded to the other substrate so that the liquid crystal alignment films face each other, and the liquid crystal is spread over the entire surface of the substrate. The entire surface of the substrate is then irradiated with UV light to harden the sealant, thereby fabricating a liquid crystal cell. In either case, it is desirable to further heat the liquid crystal cell manufactured as described above to a temperature at which the liquid crystal used assumes an isotropic phase, and then slowly cool it to room temperature to remove the flow orientation that occurs during liquid crystal filling.

[0131] As the sealing agent, for example, an epoxy resin containing a hardener and aluminum oxide spheres as spacers can be used.

[0132] Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals, with nematic liquid crystals being preferred. Examples include Schiff-based liquid crystals, azoxy liquid crystals, biphenyl liquid crystals, phenylcyclohexane liquid crystals, ester liquid crystals, terphenyl liquid crystals, biphenylcyclohexane liquid crystals, pyrimidine liquid crystals, dioxane liquid crystals, bicyclooctane liquid crystals, and cubane liquid crystals. These liquid crystals may also be supplemented with cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonaate, and cholesteryl carbonate; chiral agents such as those sold under the trade names "C-15" and "CB-15" (manufactured by Merck); and ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate. The liquid crystal may also contain an anisotropic dye. The term "dye" refers to a material capable of intensively absorbing or transforming light in at least a portion or all of the visible light range, e.g., the wavelength range of 400 nm to 700 nm. The term "anisotropic dye" refers to a material capable of anisotropically absorbing light in at least a portion or all of the visible light range. The use of such dyes can control the color of a liquid crystal cell. The type of anisotropic dye is not particularly limited; for example, black dyes or color dyes can be used. The ratio of the anisotropic dye to the liquid crystal is appropriately selected within a range that does not impair the desired physical properties. For example, the anisotropic dye can be included in a ratio of 0.01 to 5 parts by weight per 100 parts by weight of the liquid crystal compound, but this ratio can be modified within an appropriate range as needed.

[0133] (1-3B) When manufacturing a PSA type liquid crystal display element, a liquid crystal cell is constructed in the same manner as in (1-3A) above, except that a photopolymerizable compound such as any of the following formulae (w-1) to (w-5) is injected or dropped together with the liquid crystal. [ka]

[0134] Thereafter, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates. The voltage applied here can be, for example, a direct current or alternating current of 5 to 50 V. The light to be irradiated can be, for example, ultraviolet light and visible light containing light with a wavelength of 150 to 800 nm, but ultraviolet light containing light with a wavelength of 300 to 400 nm is preferred. The light source for the irradiated light can be, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, or an excimer laser. Ultraviolet light in the above-mentioned preferred wavelength range can be obtained by using the light source in combination with, for example, a filter diffraction grating. The light irradiation dose is preferably 100 mJ / cm. 2 More than 30,000mJ / cm 2 less than 100 to 20,000 mJ / cm 2 is.

[0135] (1-3C) When a coating film is formed on a substrate using a liquid crystal alignment agent containing a compound (polymer or additive) having a photopolymerizable group, a liquid crystal cell may be constructed in the same manner as in (1-3A) above, followed by a process of irradiating the liquid crystal cell with light while applying a voltage between the conductive films of a pair of substrates to produce a liquid crystal display element. This method allows the advantages of the PSA mode to be realized with a small amount of light irradiation. The light irradiation to the liquid crystal cell may be performed while the liquid crystal is driven by applying a voltage, or may be performed while applying a low voltage that does not drive the liquid crystal. The applied voltage may be, for example, 0.1 to 30 V, DC or AC. The conditions for the light irradiation can be the same as those described in (1-3B) above. The light irradiation treatment here corresponds to the light irradiation treatment in contact with the liquid crystal layer.

[0136] The liquid crystal display element according to the present invention can be obtained by laminating a polarizing plate to the outer surface of the liquid crystal cell. Examples of the polarizing plate to be laminated to the outer surface of the liquid crystal cell include a polarizing film called an "H film" made by stretching and aligning polyvinyl alcohol and absorbing iodine, sandwiched between cellulose acetate protective films, and a polarizing plate made of the H film itself.

[0137] The liquid crystal display element according to 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. [Example]

[0138] The present invention will be further specifically described below with reference to examples. However, the present invention is not limited to these examples. In the following, the abbreviations of the compounds and the methods for measuring the respective properties are as follows. (acid dianhydride) DC-1 to DC-3: Compounds represented by the following formulas (DC-1) to (DC-3), respectively (diamine) DA-1 to DA-10: Compounds represented by the following formulas (DA-1) to (DA-10), respectively (solvent) NMP: N-methyl-2-pyrrolidone BCS: Butyl cellosolve [ka] (Boc represents a tert-butoxycarbonyl group.)

[0139] The methods for measuring the following properties and the methods for preparing the measurement samples etc. are as follows. <Viscosity measurement> The viscosity of the polyamic acid solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL (milliliters), a cone rotor TE-1 (1°34', R24), and a temperature of 25°C.

[0140] <Molecular weight measurement> The molecular weights of the polyimide precursor and polyimide were measured using a room temperature gel permeation chromatography (GPC) apparatus (GPC-101) (manufactured by Showa Denko K.K.) and columns (KD-803, KD-805) (manufactured by Showa Denko K.K.) as follows. Column temperature: 50℃ Eluent: N,N-dimethylformamide (additives: lithium bromide monohydrate (LiBr·H2O) 30 mmol / L, phosphoric acid anhydrous crystal (o-phosphoric acid) 30 mmol / L, tetrahydrofuran (THF) 10 ml / L) Flow rate: 1.0ml / min Standard samples for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight: approximately 900,000, 150,000, 100,000, and 30,000) (manufactured by Tosoh Corporation) and polyethylene glycol (molecular weight: approximately 12,000, 4,000, and 1,000) (manufactured by Polymer Laboratory Co., Ltd.).

[0141] <Measurement of imidization rate> 20 mg of polyimide powder was placed in an NMR (nuclear magnetic resonance) sample tube (NMR sampling tube standard, φ5 (Kusano Scientific Co., Ltd.)), and 0.53 mL of deuterated dimethyl sulfoxide (DMSO-d6, 0.05 wt% TMS (tetramethylsilane) mixture) was added. The solution was sonicated to completely dissolve it. Proton NMR at 500 MHz was measured using an NMR spectrometer (JNW-ECA500) (JEOL Datum Co., Ltd.). The imidization ratio was calculated using the integrated peak value of this proton and the integrated peak value of the proton derived from the NH group of the amic acid, which appeared around 9.5 to 10.0 ppm, according to the following equation: Imidization rate (%) = (1 - α x / y) x 100 In the above formula, x is the integrated value of the proton peak derived from the NH group of the amic acid, y is the integrated value of the peak of the reference proton, and α is the ratio of the number of reference protons to one NH group proton of the amic acid in the case of polyamic acid (imidization rate 0%).

[0142] DA-1 to DA-4 are novel compounds that have not been published in the literature, and their synthesis methods are described in detail below.

[0143] The products described in the following Synthesis Examples 1 to 4 are 1 The product was identified by H-NMR analysis (analysis conditions are as follows). Equipment: BRUKER ADVANCE III-500MHz Measurement solvent: DMSO-d6 Reference material: tetramethylsilane (TMS) (δ 0.0 ppm for 1 H)

[0144] (Synthesis Example 1: Synthesis of DA-1) DA-1 was synthesized according to the following procedure. [ka]

[0145] <Synthesis of compound [1]> (4,4'-Dinitro-[1,1'-biphenyl]-2,2'-diyl)dimethanol (120 g, 0.394 mol) was added to chloroform (720 g) and thionyl chloride (117 g, 0.986 mol). Pyridine (1 mL) was added and the mixture was stirred at 50°C for 19 hours. After the reaction was completed, water (720 g) was added to the reaction mixture for separation and washing, and chloroform (720 g) was added for separation and extraction. The resulting organic phase was concentrated, and the crystals were slurry-washed with hexane (20.0 g) and filtered. The resulting crystals were dried to obtain compound [1] (yield: 115 g, 0.337 mol, 85%). 1H-NMR(500MHz) in DMSO-d6:8.59(d,J=3.0Hz,2H),8.36-8.32(m,2H),7.63(m,2H),4.69(d,J=15.0Hz,2H),4.48(d,J=14.5Hz,2H).

[0146] <Synthesis of compound [2]> Compound [1] (115 g, 0.337 mol) was added with N,N-dimethylformamide (460 g) and potassium phthalimide (131 g, 0.708 mol) and stirred for 19 hours at 25° C. After the reaction was completed, ethyl acetate (960 g) and water (960 g) were added, and white crystals precipitated. These were filtered, washed with water (600 g), and the resulting crystals were dried to obtain compound [2] (yield: 125 g, 0.222 mol, 66%). 1 H-NMR(500MHz) in DMSO-d6:8.26(d,J=2.5Hz,2H),8.17-8.14(m,2H),7.85-7.80(m,8H),7.56(d,J=10.5Hz,2H),4.74-4.62(m,4H).

[0147] <Synthesis of compound [3]> Compound [2] (119 g, 0.212 mol) was added to tetrahydrofuran (595 g) and hydrazine monohydrate (79%) (174 g, 4.29 mol) and stirred at 65 °C for approximately 3 days. After the reaction was completed, white crystals precipitated outside the system. These were removed by filtration, and the filtrate was concentrated and dried to obtain crude compound [3] (yield: 65.6 g). The resulting compound was used directly in the next step. 1 H-NMR(500MHz) in DMSO-d6:8.55(d,J=2.4Hz,2H),8.18-8.15(m,2H),7.41(d,J=8.4Hz,2H),3.50-3.38(m,4H),3.26(br,4H).

[0148] <Synthesis of compound [4]> To the crude product of compound [3] (50.0 g, 0.165 mol), methanol (300 g) was charged and stirred while cooling in an ice bath. Di-tert-butyl dicarbonate (74.0 g, 0.339 mol) diluted with methanol (50.0 g) was added dropwise while paying attention to exotherm, and after the dropwise addition was completed, it was stirred at 25 °C for 3 hours. Since white crystals had precipitated outside the system, these were filtered, the cake was washed with methanol (150 g), and the obtained crystals were dried to obtain compound [4] (yield: 65.7 g, 0.131 mol, yield 79%). 1 H-NMR(500MHz) in DMSO-d6: 8.27(s,2H), 8.22(d,J=10.0Hz,2H), 7.47-7.37(m,4H), 3.95-3.76(m,4H), 1.36(s,18H).

[0149] <Synthesis of DA-1> To compound [4] (50.0 g, 0.0995 mol), tetrahydrofuran (300 g) and methanol (60.0 g) were added. After nitrogen substitution, 5% palladium carbon (hydrous product) (4.00 g) was added and nitrogen substitution was carried out again. A hydrogen Tedlar bag was attached and it was stirred at 25 °C for 24 hours. After the reaction was completed, it was passed through a membrane filter to remove palladium carbon, and then the filtrate was concentrated and dried to obtain DA-1 (yield: 42.9 g, 0.0969 mol, yield 97%). 1 H-NMR(500MHz) in DMSO-d6: 6.95(t,J=5.0Hz,2H), 6.66(d,J=10.0Hz,2H), 6.56(s,2H), 6.44(m,2H), 4.97(s,4H), 3.82-3.74(m,8H), 1.38(s,18H).

[0150] (Synthesis Example 2: Synthesis of DA-2) DA-2 was synthesized according to the following procedure.

Chemical formula

[0151] <Synthesis of compound [5]> 2-Chloroethylamine hydrochloride (51.9 g, 0.447 mol) and triethylamine (49.6 g, 0.490 mol) were added to methanol (204 g) and stirred under ice-cooled conditions under a nitrogen atmosphere. Di-tert-butyl dicarbonate (117 g, 0.536 mol) dissolved in methanol (102 g) was added dropwise, carefully monitoring the heat generation. Once the heat generation ceased, the mixture was stirred at 25 °C for 15 hours. After the reaction was complete, 4-dimethylaminopyridine (0.543 g, 4.44 mmol) was added and the mixture was stirred at 60 °C for 1 hour to react the excess di-tert-butyl dicarbonate with the methanol. The reaction mixture was then concentrated. Ethyl acetate (300 g) was added to the concentrated crude product, which was then washed with purified water (300 g x 3 times). The organic phase was concentrated under reduced pressure and dried to obtain crude compound [5] (yield: 77.8 g). The resulting compound was used directly in the next step.

[0152] <Synthesis of compound [6]> 2-Amino-5-nitrophenol (54.8 g, 0.356 mol), potassium carbonate (61.8 g, 0.447 mol), and potassium iodide (5.90 g, 0.0355 mol) were added to N,N-dimethylacetamide (210 g) and heated to 100 °C. Crude compound [5] (77.8 g) dissolved in N,N-dimethylacetamide (70.0 g) was added dropwise and stirred at 100 °C for 21 hours. Ethyl acetate (280 g) and purified water (280 g) were added to the reaction solution, and the precipitated crystals were separated by filtration to obtain crude compound [6]. The filtrate was concentrated, and ethyl acetate (90.0 g) and methanol (340 g) were added and stirred to precipitate crystals. The mixture was then filtered and the resulting crystals were washed with methanol (140 g) to obtain crude compound [6]. The crude products obtained in the above two steps were combined and crystallized with ethyl acetate (480 g) and toluene (480 g). The crystals were filtered and dried to obtain compound [6] (yield: 63.3 g, 0.213 mol). 1H-NMR(500MHz) in DMSO-d6: 7.74(dd, 1H, J = 8.8Hz, 2.4Hz), 7.53(d, 1H, J = 2.4Hz), 6.64(d, 1H, J = 8.8Hz), 7.20(t, 1H, J = 6.0Hz), 4.00 - 3.97(m, 2H), 6.54(br, 2H), 3.39 - 3.34(m, 2H), 1.93(s, 9H).

[0153] <Synthesis of Compound [7]> To compound [6] (15.0 g, 0.0505 mol), tetrahydrofuran (90.0 g) and pyridine (4.28 g, 0.0541 mol) were charged, and the mixture was stirred while cooling to 5 °C in an ice bath. Adipic acid dichloride (4.50 g, 0.0246 mol) diluted with tetrahydrofuran (15.0 g) was added dropwise, and after the addition was complete, the mixture was stirred at 25 °C for 19 hours. After completion of the reaction, water (105 g) was added to the reaction solution, methanol (315 g) was added, and the mixture was stirred for 40 minutes to precipitate crystals. These were filtered, and the obtained crystals were dried to obtain compound [7] (yield: 15.6 g, 0.0221 mol, yield 90%). 1 H-NMR(500MHz) in DMSO-d6: 9.23(s, 2H), 8.49(d, J = 9.0Hz, 2H), 7.90 - 7.87(m, 2H), 7.77(s, 2H), 7.23(t, J = 5.5Hz, 2H), 4.14(br, 4H), 3.40(br, 4H), 2.59(br, 4H), 1.70(br, 4H), 1.42(s, 18H).

[0154] <Synthesis of DA-2> To compound [7] (15.5 g, 0.0220 mol), N,N-dimethylformamide (465 g) was added. After nitrogen substitution, 5% palladium carbon (hydrous product) (1.24 g) was added, followed by nitrogen substitution. A hydrogen Tedlar bag was attached, and the mixture was stirred at 50 °C for five days. After completion of the reaction, the mixture was passed through a membrane filter to remove palladium carbon. Then, ethyl acetate (930 g) was added to the filtrate, and the mixture was washed by liquid separation three times with water (800 g). The organic phase was concentrated and dried to obtain DA-2 (yield: 9.41 g, 0.0146 mol, yield 66%). 1H-NMR(500MHz) in DMSO-d6: 8.54(s, 2H), 7.46(d, J = 8.5Hz, 2H), 7.05(t, J = 5.5Hz, 2H), 6.20(d, J = 2.0Hz, 2H), 6.09 - 6.07(m, 2H), 4.90(s, 4H), 3.83(t, J = 5.5Hz, 4H), 3.30(br, 4H), 2.33(br, 4H), 1.62(br, 4H), 1.42(s, 18H).

[0155] (Synthesis Example 3: Synthesis of DA-3) DA-3 was synthesized according to the following procedure.

Chemical Structure

[0156] (Synthesis of Compound [8]) To compound [6] (15.0 g, 0.0505 mol), tetrahydrofuran (90.0 g) and pyridine (4.28 g, 0.0541 mol) were charged, and the mixture was stirred while cooling to 5 °C in an ice bath. Terephthaloyl chloride (5.00 g, 0.0246 mol) diluted with tetrahydrofuran (15.0 g) was added dropwise, and after the addition, the mixture was stirred at 25 °C for 20 hours. After completion of the reaction, water (105 g) was added to the reaction solution, methanol (315 g) was added, and the mixture was stirred for 40 minutes to precipitate crystals. These were filtered, and the obtained crystals were dried to obtain compound [8] (yield: 14.4 g, 0.0198 mol, yield 81%). 1 H-NMR(500MHz) in DMSO-d6: 9.80(s, 2H), 8.49(d, J = 9.0Hz, 2H), 8.17(s, 4H), 7.98 - 7.96(m,​​​​​Compound [8] (14.3 g, 0.0203 mol) was added to N,N-dimethylformamide (489 g) and purged with nitrogen. Then, 5% palladium carbon (wet) (1.14 g) was added and purged with nitrogen. A hydrogen Tedlar bag was attached and the mixture was stirred at 50 °C for approximately 5 days. After the reaction was complete, the palladium carbon was removed by passing the mixture through a membrane filter. Ethyl acetate (978 g) was added to the filtrate, which was then washed three times with water (800 g). The organic phase was concentrated and dried to obtain crude DA-3 crystals. These were crystallized with ethyl acetate and hexane, filtered, and the resulting crystals were dried to obtain DA-3 (yield: 10.0 g, 0.0151 mol, 74%). 1 H-NMR(500MHz) in DMSO-d6:9.30(s,2H),8.05(s,4H),7.44(d,J=8.5Hz,2H),7.01(t,J=5.5Hz,2H),6.29(d,J=1.5Hz,2 H),6.18-6.16(m,2H),5.06(s,4H),3.91(t,J=5.0Hz,4H),3.33(br,4H),1.62(br,4H),1.42(s,18H).

[0158] (Synthesis Example 4: Synthesis of DA-4) DA-4 was synthesized by the following procedure. [ka]

[0159] <Synthesis of compound [9]> Ethylene glycol (13.7 g, 0.221 mol) was charged with N,N-dimethylacetamide (150 g) and potassium carbonate (67.0 g, 0.485 mol), and the mixture was heated and stirred at an internal temperature of 100 °C. 2-Fluoro-5-nitrobenzonitrile (76.0 g, 0.458 mol) dissolved in N,N-dimethylacetamide (300 g) was added dropwise via a dropping funnel over 50 minutes, followed by heating and stirring for 6 hours from the end of the addition. After the reaction was completed, the reaction mixture was cooled and poured into stirred water (2250 g) for water-based crystallization. This mixture was filtered, and the resulting wet crystals were added to tetrahydrofuran (100 g) and stirred. A 100 g mixture of concentrated hydrochloric acid and methanol (1 / 1) was added and filtered. The filtered crystals were dried to obtain compound [9] (yield: 54.6 g, 0.700 mol, 70%).

[0160] <Synthesis of compound

[10] > To compound [9] (30.5 g, 0.0861 mol), tetrahydrofuran (305 g) was added and the mixture was purged with nitrogen. Borane-tetrahydrofuran complex (287 mL, 0.9 mol / L solution: 0.258 mol) was added dropwise at 25°C. After the addition was complete, the mixture was heated to reflux at 65°C for 17 hours. After the reaction was complete, methanol was added to quench the excess borane, and a 1 / 1 mixed solvent of concentrated hydrochloric acid and methanol (400 g) was added and the mixture was stirred at 25°C for 14 hours. The resulting mixture was collected by Buchner filtration, washed with tetrahydrofuran, and then dried to obtain compound

[10] (yield: 19.3 g, 0.0443 mol, 51%).

[0161] <Synthesis of compound

[11] > To 19.3 g (0.0443 mol) of compound

[10] , 77.2 g of methanol and 10.3 g (0.0976 mol) of triethylamine were charged, and the mixture was stirred under ice-cooling conditions in a nitrogen atmosphere. Di-tert-butyl dicarbonate (21.3 g, 0.0976 mol) dissolved in 19.3 g of methanol was added dropwise, and the mixture was stirred at 45 °C for 15 hours. After completion of the reaction, the reaction solution was poured into 96.5 g of water for dilution and crystallization. After further adding 128 g of methanol, the mixture was filtered to obtain sticky yellow crystals. These were washed with tetrahydrofuran / methanol to remove stickiness, and then filtered to collect yellow crystals (11A). The filtrate was concentrated, washed with tetrahydrofuran / methanol in the same manner, and yellow crystals (11B) were collected by filtration. The obtained crystals (11A, 11B) were dried to obtain compound

[11] (yield: 17.1 g, 0.0304 mol, yield 69%). 1 H-NMR(500MHz) in DMSO-d6:8.23-8.18(m,2H),8.02(d,J=1.0Hz,2H),7.39(br,2H),7.31(d,J=9.0Hz,2H),4.61(s,4H),4.12(d,J=6.0Hz,4H),1.41(s,18H).

[0162] <Synthesis of DA−4> To 27.0 g (0.0480 mol) of compound

[12] , 459 g of tetrahydrofuran and 27 g of methanol were added. After nitrogen substitution, 2.16 g of 5% palladium carbon (hydrous) was added, followed by nitrogen substitution again. A hydrogen Tedlar bag was attached, and the mixture was stirred at room temperature for 3 days. Since the reaction did not proceed completely, after removing the palladium carbon by passing through a membrane filter, 2.16 g of 5% palladium carbon (hydrous) was added again, followed by nitrogen substitution, and a hydrogen Tedlar bag was attached, and the mixture was stirred at 45 °C for 2 days to complete the reaction. After completion of the reaction, the palladium carbon was removed by passing through a membrane filter, and the filtrate was concentrated. The crude product was purified by column chromatography (ethyl acetate / hexane = 2 / 1 (volume ratio)) to obtain DA-4 (yield: 13.7 g, 0.0273 mol, yield 57%). 1H-NMR(500MHz) in DMSO-d6:6.93(t,J=5.5Hz,2H),6.71(d,J=8.5Hz,2H),6.44(s,2H),6.41-6 .39(m,2H),4.63(s,4H),4.11(s,4H),4.06(d,J=6.0Hz,4H),1.34(s,18H).

[0163] "Synthesis of polyamic acid" (Synthesis Example 5) In a 50 mL four-neck flask equipped with a stirrer, 1.62 g (2.2 mmol) of a 60 wt% NMP solution of DA-1, 1.43 g (13.2 mmol) of DA-7, and 2.51 g (6.6 mmol) of DA-8 were weighed out and dissolved in 19.7 g of NMP. While stirring, 2.75 g (11.0 mmol) of DC-1 was added to the diamine solution, followed by 11.0 g of NMP. The mixture was stirred at 60 °C for 3 hours. Subsequently, while stirring, 1.94 g (9.89 mmol) of DC-2 was added to the solution, followed by 7.06 g of NMP. The mixture was stirred at 40 °C for 15 hours to obtain a polyamic acid solution (A-1, viscosity: 721 mPa s, number average molecular weight: 10,143).

[0164] (Synthesis Examples 6 to 9) Polyamic acid solutions (A-2) to (A-5) shown in Table 1 were obtained in the same manner as in Synthesis Example 5, except that the diamine component and the acid dianhydride component were changed to those shown in the table below. The viscosity and molecular weight of the obtained polyamic acid are shown in Table 1 below. [Table 1]

[0165] "Synthesis of soluble polyimides" (Synthesis Example 10) NMP was added to 25 g of the polyamic acid solution (A-1) obtained in Synthesis Example 5 to dilute it to 6.5% by mass. Then, acetic anhydride (5.76 g) and pyridine (1.79 g) were added as imidization catalysts, and the mixture was allowed to react at 50°C for 3 hours. The reaction solution was poured into 300 mL of methanol, and the resulting precipitate was filtered off. The precipitate was washed with methanol and dried under reduced pressure at 100°C to obtain polyimide powder (A-1-PI). The imidization rate of this polyimide was 52%. NMP (21.6 g) was added to 2.4 g of the polyimide powder (A-1-PI) obtained above, and the mixture was stirred at 80°C for 20 hours to dissolve the polyimide, yielding a soluble polyimide (A-1-PI) solution.

[0166] (Synthesis Examples 11 to 14) Soluble polyimide solutions (A-2-PI) to (A-5-PI) shown in Table 2 were obtained in the same manner as in Synthesis Example 10, except that the polyamic acid solution was changed to one shown in Table 2. The imidization ratios of the obtained soluble polyimides are shown in Table 2. [Table 2]

[0167] "Preparation of liquid crystal alignment agent" Example 1 NMP (6.0 g) and BCS (8.0 g) were added to the polyamic acid (A-1) solution (6.0 g) obtained in Synthesis Example 5, and the mixture was stirred at room temperature for 10 hours to obtain a liquid crystal alignment agent (PAA-1) containing 6 mass % of polyamic acid (A-1), 54 mass % of NMP, and 40 mass % of BCS.

[0168] Example 2 BCS (16.0 g) was added to the soluble polyimide (A-1-PI) solution (24.0 g) obtained in Synthesis Example 10, and the mixture was stirred at room temperature for 10 hours to obtain a liquid crystal alignment agent (SPI-1) containing 6 mass % of soluble polyimide (A-1-PI), 54 mass % of NMP, and 40 mass % of BCS.

[0169] (Examples 3 to 6 and Comparative Examples 1 to 4) Liquid crystal alignment agents (PAA-2) to (PAA-5) and (SPI-2) to (SPI-5) were obtained by carrying out the same procedures as in Example 1 or Example 2, except that the polyamic acid solution or the soluble polyimide solution was changed to that shown in Table 3 below. [Table 3]

[0170] "Preparation of seal adhesion evaluation sample" The liquid crystal alignment agents prepared in Examples 1 to 6 and Comparative Examples 1 to 4 were spin-coated onto rectangular glass substrates with transparent electrodes, measuring 30 mm in length, 40 mm in width, and 1.1 mm in thickness, and then dried on a hot plate at 70°C for 90 seconds. After that, the substrates were baked in a hot air circulating oven at 230°C for 20 minutes to form liquid crystal alignment films with a thickness of 100 nm. Two substrates were prepared in this way, and 4 μm bead spacers were applied to the liquid crystal alignment film surface of one of the substrates, followed by application of a sealant (723K1 manufactured by Kyoritsu Chemical Industry Co., Ltd.). Next, these substrates were bonded together with the liquid crystal alignment film surfaces facing each other, with an overlap width of 1 cm. The amount of sealant dispensed was adjusted so that the diameter of the sealant after bonding would be 3 mm. The two bonded substrates were then fixed with clips, and a 365 nm wavelength equivalent of 4 J / cm was applied. 2 The adhesive was then irradiated with ultraviolet light at 120°C for 1 hour and thermally cured to prepare a sample for evaluating adhesion.

[0171] "Seal adhesion measurement" Adhesion evaluation was performed using a desktop precision universal testing machine (AGS-X 500N) (Shimadzu Corporation). After fixing the edges of the top and bottom substrates of the obtained evaluation sample, the substrates were pressed from above the center, and the strength (N) at the time of peeling was measured. The pressure (N) was then normalized by the measured diameter (mm) of the sealant, and the seal adhesion (N / mm) was evaluated using this value. The results are shown in Table 4. As a result, Examples 1 to 6 obtained from diamines DA-1, DA-2, and DA-3 having two Boc amino groups had higher seal adhesion than Comparative Examples 1 and 2 obtained from diamine DA-6 having one Boc amino group. Furthermore, Examples 1 to 6 had higher seal adhesion than Comparative Examples 3 and 4, which had the same mole percentage of Boc amino groups in their compositions as Examples 1 to 6. [Table 4]

[0172] "Synthesis of polyamic acid" (Synthesis Examples 15 to 17) Using the diamine components and acid dianhydride components shown in Table 5 below, all of the diamine components were dissolved in NMP, and the acid dianhydride components were added thereto and stirred at 40°C for 15 hours to obtain polyamic acid solutions (A-6) to (A-8). In Table 5, the numbers in parentheses indicate the proportion (by molar) of each compound for the diamine component relative to 100 parts by molar of the total amount of diamines used in the synthesis, the proportion (by molar) of each compound for the dianhydride component relative to 100 parts by molar of the total amount of dianhydrides used in the synthesis, and the proportion (by molar) of each organic solvent relative to 100 parts by mass of the total amount of organic solvents contained in the prepared solution. [Table 5]

[0173] "Preparation of liquid crystal alignment agent" (Example 7 and Comparative Examples 5 to 6) Liquid crystal aligning agents (PAA-6) to (PAA-8) were obtained in the same manner as in Example 1, except that the polyamic acid solution was changed to one shown in Table 6 below. [Table 6]

[0174] "Preparation of seal adhesion evaluation sample" The liquid crystal alignment agents obtained in Example 7 and Comparative Examples 5 and 6 were filtered through a filter with a pore size of 1.0 μm, and then spin-coated onto a rectangular ITO substrate measuring 30 mm in length, 40 mm in width, and 1.1 mm in thickness. After drying for 2 minutes on a hot plate at 80°C, the substrate was baked for 30 minutes in a hot air circulating oven at 230°C to form a coating film with a thickness of 100 nm. Linearly polarized ultraviolet light with a wavelength of 254 nm and an extinction ratio of 26:1 was irradiated onto the coating surface through a polarizer at a dose of 200 mJ / cm. 2 The substrate was heated on a hot plate at 230° C. for 30 minutes to obtain a substrate with a liquid crystal alignment film. After applying 4 μm particle size spacer beads to the liquid crystal alignment film surface of the substrate thus obtained, a sealant (XN-1500T manufactured by Kyoritsu Chemical Industries) was dripped onto a position 5 mm from the short edge of the substrate. The amount of sealant dripped was adjusted so that the diameter of the sealant after lamination would be 3 mm. Next, an ITO substrate of the same size as above but without the liquid crystal alignment agent was prepared and laminated so that the substrate overlap width was 1 cm. The two laminated substrates were fixed with clips and then thermally cured at 150°C for 1 hour to prepare a sample for adhesion evaluation.

[0175] "Seal adhesion measurement" The seal adhesion (N / mm) was evaluated in the same manner as above, and the results are shown in Table 7. As a result, Example 7 obtained from diamine DA-4 having two Boc amino groups had better seal adhesion than Comparative Example 6 obtained from diamine DA-6 having one Boc amino group. Also, Example 7 obtained from diamine DA-4 having a Boc amino group at the meta position of the amino group had better seal adhesion than Comparative Example 5 obtained from diamine DA-5 having a Boc amino group at the ortho position of the amino group. [Table 7]

[0176] As can be seen from the above results, in the adhesion evaluation, the liquid crystal alignment film obtained from the liquid crystal alignment agent using diamine compound DA-1, DA-2, DA-3 or DA-4 was found to have higher adhesion than the liquid crystal alignment film obtained from the liquid crystal alignment treatment agent using diamine compound DA-5 or DA-6. Specifically, this is shown in the comparison between Examples 1 to 6 and Comparative Examples 1 to 4 shown in Table 4, and the comparison between Example 7 and Comparative Examples 5 and 6 in Table 7.

[0177] From the above, it is possible to improve the seal adhesion by using the diamine represented by formula (1) of the present invention. [Industrial Applicability]

[0178] A liquid crystal display element using a liquid crystal alignment film obtained from the liquid crystal aligning agent of the present invention can be suitably used as a liquid crystal display element, and these elements are also useful in liquid crystal displays for display purposes, as well as in light control windows and optical shutters that control the transmission and blocking of light.

[0179] The entire contents of the specification, claims and abstract of Japanese Patent Application No. 2020-23546, filed on February 14, 2020, are hereby incorporated by reference as part of the disclosure of the specification of the present invention.

Claims

1. A diamine represented by the following general formula (1): 【Chemistry 1】 (In formula (1), T １ and T ２ are each independently a single bond, —O—, —COO—, —OCO—, —NHCO—, —CONH—, —NH—, or —N(CH ３ )-,-CON(CH ３ )-, and -N(CH ３ )CO—, and W is a single bond or a divalent organic group (provided that T １ or T ２ is a single bond, W is a single bond), and Q represents a substituent represented by the following formula (2). Two Qs in a molecule may be the same or different. 【Chemistry 2】 (In formula (2), X is a single bond, —O—, —COO—, —OCO—, or —S—; R １ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, A is a Boc (tert-butoxycarbonyl) group, and n is an integer of 1 to 6.

2. A polymer obtained from the diamine of claim 1, The polymer is at least one polymer selected from the group consisting of polyimide precursors having a structural unit represented by the following formula (3) and polyimides which are imidized products thereof: 【Transformation 3】 In the formula (1), X 1 is a tetravalent organic group derived from at least one tetracarboxylic acid derivative selected from the following structures; Y 1 is a divalent organic group derived from a diamine represented by the formula (1); and R 2 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. 【Chemistry 4】 【Transformation 5】

3. The polymer according to claim 2 , wherein the structural unit represented by the formula (3) accounts for 10 mol % or more of all structural units of the polymer.

4. The diamine according to claim 1, which is represented by any one of DA-1 to DA-4 below. 【Transformation 6】 (Boc represents a tert-butoxycarbonyl group.)

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