Liquid crystal aligning agent, liquid crystal alignment film, and liquid crystal display element using the same

Abstract

To provide a liquid crystal aligning agent which exhibits good aligning properties and can form a liquid crystal alignment film having good adhesion to a sealing agent.SOLUTION: This liquid crystal aligning agent contains a polymer (A) having a repeating unit represented by the following formula (3) and a repeating unit represented by a specific formula (5). (R31 to R34 are each independently a hydrogen atom, a halogen atom, a C1-6 alkyl group, a C2-6 alkenyl group, a C2-6 alkynyl group, a C1-6 monovalent organic group having a fluorine atom, or a phenyl group, which may be the same or different from each other, provided that at least one of R31 to R34 represents a group other than a hydrogen atom within the above definitions.)SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, and a liquid crystal display element using the same. [Background technology]

[0002] Conventionally, liquid crystal devices have been widely used as display units for personal computers, mobile phones, smartphones, television receivers, etc. A liquid crystal device includes, for example, a liquid crystal layer sandwiched between an element substrate and a color filter substrate, pixel electrodes and a common electrode for applying an electric field to the liquid crystal layer, an alignment film for controlling the alignment of liquid crystal molecules in the liquid crystal layer, and thin film transistors (TFTs) for switching electric signals supplied to the pixel electrodes. Known methods for driving liquid crystal molecules include vertical electric field methods such as the TN method and the VA method, and horizontal electric field methods such as the IPS method and the FFS (fringe field switching) method.

[0003] At present, the most industrially widespread liquid crystal alignment film is produced by rubbing the surface of a film made of polyamic acid and / or polyimide obtained by imidizing the polyamic acid formed on an electrode substrate in one direction with a cloth such as cotton, nylon, or polyester, which is called a rubbing treatment. The rubbing treatment is an industrially useful method that is simple and has excellent productivity. However, with the increase in performance, definition, and size of liquid crystal display elements, various problems have become clear, such as scratches on the surface of the alignment film caused by the rubbing treatment, dust generation, effects due to mechanical force and static electricity, and even non-uniformity within the alignment treatment surface. As a liquid crystal alignment treatment method that replaces the rubbing treatment, a photoalignment method is known in which liquid crystal alignment ability is imparted by irradiating polarized radiation. As liquid crystal alignment treatments using the photoalignment method, those using a photoisomerization reaction, a photocrosslinking reaction, a photodecomposition reaction, and the like have been proposed (see Non-Patent Document 1 and Patent Document 1).

[0004] A liquid crystal alignment film, which is a component of a liquid crystal display element, is a film for uniformly aligning liquid crystals, but various other characteristics are required in addition to the uniformity of liquid crystal alignment. For example, there is a problem that electric charges are accumulated in the liquid crystal alignment film due to the voltage driving the liquid crystal, which affects the display as an afterimage or burn-in (hereinafter referred to as an afterimage caused by residual DC) and significantly reduces the display quality of the liquid crystal display element, so a liquid crystal alignment agent that overcomes these problems has been proposed (see Patent Document 2).

[0005] In addition, in the IPS and FFS driving methods, the stability of liquid crystal alignment is also important. If the stability of liquid crystal alignment is low, the liquid crystal will not return to its initial state when driven for a long time, which causes a decrease in contrast and image sticking (hereinafter referred to as AC image retention). Patent Document 3 discloses a specific liquid crystal alignment agent as a method for solving the above problem.

[0006] Furthermore, with the spread of tablets and smartphones, development of narrow-frame liquid crystal display elements that ensure as wide a display area as possible is underway. This narrowing of the frame has made it necessary to apply a sealant onto the liquid crystal alignment film, and Patent Document 4 discloses a liquid crystal alignment agent that maintains liquid crystal alignment and has good adhesion to the sealant. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 9-297313 [Patent Document 2] International Publication No. 2005 / 083504 Brochure [Patent Document 3] International Publication No. 2015 / 050135 Brochure [Patent Document 4] International Publication No. 2015 / 060360 Brochure [Non-patent literature]

[0008] [Non-Patent Document 1] "Liquid Crystal Photo-Alignment Film" Kidowaki, Ichimura, Functional Materials, November 1997, Vol. 17, No. 11, pp. 13-22 Summary of the Invention [Problem to be solved by the invention]

[0009] Furthermore, there is an ever-increasing demand for higher definition liquid crystal display elements, and it is becoming more important than ever to exhibit good display quality. The present invention has been made in consideration of the above circumstances, and has as its main object to provide a liquid crystal alignment film that has good liquid crystal alignment properties and good adhesion to a sealant, and a liquid crystal alignment agent that enables a narrow frame due to the good adhesion between the liquid crystal alignment film and the sealant, thereby enabling the production of a liquid crystal display element that exhibits good display quality. [Means for solving the problem]

[0010] As a result of intensive research, the present inventors have found that the above problems can be solved by using a liquid crystal aligning agent containing a polymer component having a specific repeating unit, and have thus completed the present invention. The present invention relates to the following. A liquid crystal aligning agent comprising a polymer (A) having repeating units represented by the following formulae (1), (2), (3) and (4). [ka] (R1 to R4 each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different, but at least one of R1 to R4 represents a group other than a hydrogen atom as defined above. Y1 represents a divalent organic group having a partial structure represented by the following formula (H).) [ka] (Q3 Ha-(CH2) n (n is an integer of 2 to 20), and any -CH2- may be replaced with a group selected from -O- and -C(=O)-, but the oxygen atoms are not directly bonded to each other. Any hydrogen atoms on the two benzene rings may be replaced with a monovalent organic group. * represents a bond.) [ka] (X2 is a tetravalent organic group having an alicyclic structure of 5 or more members. Y2 is a divalent organic group having a partial structure represented by the above formula (H).) [ka] (R in Equation (3) 31 From R 34 are defined the same as R1 to R4 in the above formula (1), respectively. X4 in the formula (4) is defined the same as X2 in the above formula (2). Y3 and Y4 each represent a divalent organic group represented by the following formula (I). [ka] (* represents a bond.) Effect of the Invention

[0011] According to the liquid crystal alignment agent of the present invention, a liquid crystal alignment film having good liquid crystal alignment and good adhesion to a sealant can be obtained, and because of the good adhesion between the liquid crystal alignment film and the sealant, a further narrowing of the frame can be achieved, thereby obtaining a liquid crystal display element exhibiting good display quality. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Each component contained in the liquid crystal aligning agent of the present invention and other components that are optionally blended as necessary will be described below. <Polymer (A)> The liquid crystal aligning agent of the present invention contains a polymer (A) having repeating units represented by the above formula (1), (2), (3) and (4). By using such a constitution, a liquid crystal alignment film with little AC afterimage can be obtained, and a liquid crystal display element with excellent contrast can be obtained.

[0013] In the above formulas (1) and (2), X2, Y1, Y2, R1, R2, R3, and R4 are as defined above.

[0014] Specific examples of the alkyl group having 1 to 6 carbon atoms in R1 to R4 include a methyl group, an ethyl group, a propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, and an n-pentyl group. Specific examples of the alkenyl group having 2 to 6 carbon atoms in R1 to R4 include a vinyl group, a propenyl group, and a butynyl group, which may be linear or branched. Specific examples of the alkynyl group having 2 to 6 carbon atoms in R1 to R4 include an ethynyl group, a 1-propynyl group, and a 2-propynyl group. Examples of the halogen atom in R1 to R4 include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Examples of the monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom include a fluoromethyl group and a trifluoromethyl group. From the viewpoint of high photoreactivity, R1 to R4 are hydrogen atoms or methyl groups, and it is preferable that at least one of R1 to R4 is a methyl group, and more preferably at least two of R1 to R4 are methyl groups. It is even more preferable that R1 and R4 are methyl groups, and R2 and R3 are hydrogen atoms.

[0015] Specific examples of the monovalent organic group substituting any hydrogen atom on the benzene ring in the above formula (H) include a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, and a monovalent organic group containing a fluorine atom and having 1 to 6 carbon atoms, and include the structures exemplified above for R1 to R4. As the partial structure represented by the above formula (H), from the viewpoint of reducing the occurrence of AC image sticking, partial structures represented by any of the following formulae (H-1) to (H-7) can be mentioned. [ka]

[0016] Preferred specific examples of Y1 in the above formula (1) include divalent organic groups represented by any of the following formulae (h-1) to (h-8), from the viewpoint of reducing the occurrence of AC afterimages. [ka]

[0017] The polymer (A) has a repeating unit represented by the above formula (2) from the viewpoint of increasing heat resistance. The tetravalent organic group of X2 in formula (2) is preferably a tetravalent organic group having a 5- to 8-membered alicyclic structure, and more preferably a tetravalent organic group having a 5- to 7-membered alicyclic structure. The alicyclic structure having 5 or more members means that, when the alicyclic structure to which the imide group is bonded is a polycyclic structure, each of the rings contained in the polycyclic structure has 5 or more atoms constituting the ring. The alicyclic structure may be bonded to at least one of the two imide groups, and may have a chain hydrocarbon structure or an aromatic ring structure together with the alicyclic structure.

[0018] Preferred specific examples of X2 include tetravalent organic groups represented by any of the following formulas (X2-1) to (X2-12). [ka]

[0019] From the viewpoints of reducing the occurrence of AC image retention and enhancing the contrast of a liquid crystal display device, X2 in formula (2) is more preferably any one of (X2-1) to (X2-4). Preferable specific examples of Y2 in the above formula (2) are the same as the preferable specific examples of Y1 in the above formula (1).

[0020] In order to reduce AC afterimages, the polymer (A) contains the repeating units represented by the above formula (1) and the repeating units represented by the above formula (2) in an amount of preferably 1 to 95 mol %, more preferably 5 to 90 mol %, based on all repeating units. The ratio ((1):(2)) of the repeating units represented by the above formula (1) to the repeating units represented by the above formula (2) in the polymer (A) is preferably 70:30 to 99:1, more preferably 75:25 to 98:2, and even more preferably 80:20 to 97:3.

[0021] The polymer (A) has a repeating unit represented by the above formula (3) and a repeating unit represented by the above formula (4) from the viewpoint of improving the contrast and seal adhesion of a liquid crystal display device. From the viewpoint of reducing AC afterimages, the polymer (A) preferably contains 5 to 99 mol %, and more preferably 10 to 95 mol %, of the total of the repeating units represented by the formula (3) and the repeating units represented by the formula (4) based on all the repeating units. The ratio ((3):(4)) of the repeating unit represented by the above formula (3) to the repeating unit represented by the above formula (4) in the polymer (A) is preferably 70:30 to 99:1, more preferably 75:25 to 98:2, and even more preferably 80:20 to 97:3.

[0022] The ratio ((1):(3)) of the repeating unit represented by formula (1) to the repeating unit represented by formula (3) in the polymer (A) is preferably 1:99 to 99:1, more preferably 5:95 to 80:20, and even more preferably 10:90 to 70:30. The ratio ((2):(4)) of the repeating unit represented by formula (2) to the repeating unit represented by formula (4) in the polymer (A) is preferably 1:99 to 99:1, more preferably 5:95 to 80:20, and even more preferably 10:90 to 70:30.

[0023] The polymer (A) preferably contains the repeating units represented by the above formulas (1), (2), (3) and (4) in an amount of 6 to 100 mol %, and more preferably 15 to 100 mol %, based on the total repeating units contained in the polymer (A).

[0024] From the viewpoint of further enhancing adhesion to a sealing material, the polymer (A) may have at least one repeating unit selected from the group consisting of a repeating unit represented by the following formula (5) and a repeating unit represented by the following formula (6). [ka] (R 51 From R 54 are the same as R1 to R4 in the above formula (1), including preferred specific examples, and Y5 and Y6 each independently represent a divalent organic group having a partial structure represented by the following formula (J-1) or a divalent organic group represented by the following formula (J-2). X6 in formula (6) is the same as X2 in the above formula (2). [ka]

[0025] In the above formula (J-1) and formula (J-2), Q5 is a single bond, -(CH2) n -(n is an integer from 1 to 20), or -(CH2) n -O-, -COO-, -OCO-, -NQ9-, -NQ9CO-, -CONQ9-, -NQ9CONQ, provided that any -CH2- in 10 Q and Q are groups that can be replaced by -, -NQCOO-, or -OCOO-. 10 each independently represents a hydrogen atom or a monovalent organic group. Q6 and Q7 each independently represent -H, -NHD, -N(D)2, a group having -NHD, or a group having -N(D)2. Q8 represents -NHD, -N(D)2, a group having -NHD, or a group having -N(D)2. D represents a carbamate-based protecting group, and examples of the carbamate-based protecting group include a tert-butoxycarbonyl group or a 9-fluorenylmethoxycarbonyl group. However, at least one of Q5, Q6, and Q7 has a carbamate-based protecting group in the group. *1 represents a bond.

[0026] Preferred specific examples of Y5 and Y6 from the viewpoint of reducing AC afterimages include divalent organic groups represented by any one of the following formulas (J-1-a) to (J-1-d) and (J-2-1): Boc represents a tert-butoxycarbonyl group. [ka]

[0027] The polymer (A) may further have at least one repeating unit selected from the group consisting of repeating units represented by the following formulae (PI-A-1) and (PA-1), in addition to the repeating units represented by the above formulae (1) to (4) and the repeating units represented by the above formulae (5) and (6). [ka]

[0028] In formula (PI-A-1), X I1 represents a tetravalent organic group, Y I1 represents a divalent organic group. I1 is a tetravalent organic group represented by the following formula (g) or has the same meaning as X2 in the above formula (2), Y I1 represents a structure other than the divalent organic group having the partial structure represented by the above formula (H), the divalent organic group represented by the above formula (I), the divalent organic group having the partial structure represented by the above formula (J-1), and the divalent organic group represented by the above formula (J-2). X I1Examples of the tetravalent organic group include the tetravalent organic groups represented by the following formula (g) and the tetravalent organic groups exemplified as X2 in the above formula (2), as well as the tetravalent organic groups represented by the following formula (X I1 -1)~(X I1 -13), and a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride. [ka] (R1, R2, R3, and R4 are defined as R1, R2, R3, and R4 in the above formula (1).)

[0029] [ka]

[0030] Above X 11 An aromatic tetracarboxylic dianhydride that gives a tetravalent organic group is an acid dianhydride obtained by intramolecular dehydration of a carboxyl group bonded to an aromatic ring such as a benzene ring or a naphthalene ring. Specific examples include a tetravalent organic group represented by any one of the following formulae (X3-1) to (X3-2) and a tetravalent organic group represented by any one of the following formulae (Xr-1) to (Xr-7). [ka] (x and y each independently represent a single bond, an ether (-O-), a carbonyl (-CO-), an ester (-COO-), an alkanediyl group having 1 to 5 carbon atoms, 1,4-phenylene, a sulfonyl, or an amide group. j and k each represent 0 or 1. * represents a bond.) [ka]

[0031] In formula (PI-A-1), Y I1Specific examples of the divalent organic group include a divalent organic group having a partial structure represented by the above formula (H), a divalent organic group represented by the above formula (I), a divalent organic group having a partial structure represented by the above formula (J-1), and a divalent organic group represented by the above formula (J-2), as well as a divalent organic group represented by any of the following formulas (o-1) to (o-23), and a group represented by any of the formulas (Y-1) to (Y-167) described in International Publication No. 2018 / 117239 (hereinafter also referred to as WO). [ka]

[0032] [ka]

[0033] [ka]

[0034] In formula (PA-1), X A1 represents a tetravalent organic group, Y A1 represents a divalent organic group. A1 Specific examples of X in the above formula (PI-A-1) include I1 Examples of the structure are shown in Y A1 Specific examples of the above include Y in formula (PI-A-1). I1 Examples of the structure include those shown in

[0035] In formula (PA-1), R A1 is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. A11 , Z A12 are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may have a substituent, an alkenyl group having 2 to 10 carbon atoms which may have a substituent, an alkynyl group having 2 to 10 carbon atoms which may have a substituent, a tert-butoxycarbonyl group, or a 9-fluorenylmethoxycarbonyl group.

[0036] Above R A1Specific examples of the alkyl group having 1 to 5 carbon atoms include a methyl group, an ethyl group, a propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, an n-pentyl group, etc. From the viewpoint of ease of imidization by heating, R1 is preferably a hydrogen atom or a methyl group.

[0037] Above Z A11 , Z A12 Specific examples of the alkyl group having 1 to 10 carbon atoms include, in addition to the specific examples of the alkyl group having 1 to 5 carbon atoms exemplified for R1 above, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, etc. A11 , Z A12 Specific examples of the alkenyl group having 2 to 10 carbon atoms include a vinyl group, a propenyl group, and a butynyl group, which may be linear or branched. A11 , Z A12 Specific examples of the alkynyl group having 2 to 10 carbon atoms include an ethynyl group, a 1-propynyl group, and a 2-propynyl group. Z A11 , Z A12 may have a substituent, and examples of the substituent include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a hydroxyl group, a cyano group, and an alkoxy group.

[0038] When the polymer A contains the repeating unit represented by the formula (5) and the repeating unit represented by the formula (6), the ratio ((5):(6)) is preferably 70:30 to 99:1, more preferably 75:25 to 98:2, and even more preferably 80:20 to 97:3.

[0039] In the polymer (A), the sum of the repeating units represented by the formula (5) and the repeating units represented by the formula (6) is preferably 1 to 40 mol %, more preferably 1 to 30 mol %, and even more preferably 5 to 30 mol %, based on the total repeating units contained in the polymer (A). In this case, the total amount of the repeating units represented by the above formulas (1), (2), (3) and (4) is preferably 6 to 99 mol %, more preferably 15 to 99 mol %, and still more preferably 15 to 95 mol %, based on the total amount of repeating units contained in the polymer (A).

[0040] <Second Polymer> The liquid crystal aligning agent of the present invention is a composition containing the above polymer (A) and an organic solvent, and may contain two or more polymers (A) having different structures. The liquid crystal aligning agent of the present invention may also contain a polymer other than the polymer (A) (hereinafter, also referred to as a second polymer) and various additives. When the liquid crystal aligning agent of the present invention contains a second polymer, the content of the polymer (A) in the total polymer components is preferably 5 mass % or more, more preferably 5 to 95 mass %, and more preferably 10 to 90 mass %.

[0041] Examples of the second polymer include polyamic acid, polyimide, polyamic acid ester, polyester, polyamide, polyurea, polyorganosiloxane, cellulose derivatives, polyacetal, polystyrene or derivatives thereof, poly(styrene-phenylmaleimide) derivatives, and poly(meth)acrylates.

[0042] 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.

[0043] An example of the tetracarboxylic dianhydride component for obtaining the second polyamic acid is a compound represented by the following formula (11): The tetracarboxylic dianhydride component may be composed of two or more types of compounds. [ka] (A is a tetravalent organic group, preferably a tetravalent organic group having 4 to 30 carbon atoms).

[0044] Preferred examples of A are shown below, but the invention is not limited to these. [ka]

[0045] Among the above, (A-1) and (A-2) are preferable from the viewpoint of further improving the photoalignment property, (A-4) is preferable from the viewpoint of further improving the relaxation speed of the accumulated charge, and (A-15) to (A-17), etc. are preferable from the viewpoint of further improving the liquid crystal alignment property and the relaxation speed of the accumulated charge.

[0046] 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. Two A9's each independently represent 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. From the viewpoint of liquid crystal alignment, A9 is preferably a hydrogen atom or a methyl group.)

[0047] For the purpose of improving the electrical properties and relaxation properties, Y9 is preferably a divalent organic group having a secondary or tertiary nitrogen atom, or a divalent organic group having --NH--CO--NH-- in the molecule. Specific examples of the diamine represented by formula (12) in the case where Y9 is a divalent organic group having a secondary or tertiary nitrogen atom include any of the following diamines (a) to (d).

[0048] (a) A diamine having a pyrrole structure as described in WO2017 / 126627, preferably a diamine having a structure represented by the following formula (pr): [ka] (R 1 represents a hydrogen atom, a fluorine atom, a cyano group, a hydroxyl group, or a methyl group.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 a site bonded to the benzene ring in formula (pr), and *2 represents a site bonded to the amino group in formula (pr). Ph represents a phenylene group. n is 1 to 3.

[0049] (b) A diamine having a pyrrole structure as described in WO2018 / 062197, preferably a diamine having a structure represented by the following formula (pn):

[0050] [ka] (R 1 and R 2 R each independently represents a hydrogen atom or a methyl group. 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 a site bonded to the benzene ring in formula (pn), *2 represents a site bonded to the amino group in formula (pn), Ph represents a phenylene group, and n represents 1 to 3.

[0051] (c) A diamine having a carbazole structure described in WO2018 / 110354, preferably a diamine having a structure represented by the following formula (cz): [ka] (R 1 represents a hydrogen atom or a methyl group, R 2 represents a methyl group.)

[0052] (d) diamines having a nitrogen-containing heterocycle as described in

[0173] to

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

[0050] of JP2016-218149, and diamines represented by the following formula (BP): [ka] (X is a biphenyl ring or a fluorene ring; Y is a benzene ring, a biphenyl ring, or a group selected from -Ph-Z-Ph-, where Ph is a phenylene group; Z is a divalent group represented by -O-, -NH-, -CH2-, -SO2-, -C(CH3)2-, or -C(CF3)2-; A and B are hydrogen atoms or methyl groups), 2,3-diaminopyridine, 2,6-diaminopyridine, 3,4-diaminopyridine, 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 Azine, 2,4-diamino-6-methoxy-1,3,5-triazine, 2,4-diamino-6-phenyl-1,3,5-triazine, 2,4-diamino-6-methyl-1,3,5-triazine, 2,4-diamino-1,3,5-triazine, 4,6-diamino-2-vinyl-1,3,5-triazine, 3,5-diamino-1,2,4-triazole, 6,9-diamino-2-ethoxyacridine lactate, 3,8-di Amino-6-phenylphenanthridine, 1,4-diaminopiperazine, 3,6-diaminoacridine, bis(4-aminophenyl)-N-phenylamine, 4,4'-diphenyl-N-methylamine, 4,4'-diaminodiphenylamine, 3,6-diaminocarbazole, 9-methyl-3,6-diaminocarbazole, 9-ethyl-3,6-diaminocarbazole, and diamines represented by the following formula (w1) or (w2).

[0053] [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 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-, -NR- (R represents a methyl group), pyrrolidine, piperidine, and piperazine.)

[0054] Specific examples of the diamine represented by formula (12) when Y9 is a divalent organic group having -NH-CO-NH- in the molecule include diamines represented by formula (13) below, where A1 is -NH-CO-NH-, a group in which at least one -CH2- of an alkylene group having 2 to 20 carbon atoms is substituted with -NH-CO-NH-, or a group in which at least one -CH2- of an alkylene 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 the diamine include diamines represented by any of the following formulas (U-1) to (U-9).

[0055] [ka] (A1 represents a single bond, -NH-CO-NH-, or an alkylene group having 2 to 20 carbon atoms (wherein any -CH2- in the alkylene group may be substituted with -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), or -NH-CO-NH-). A2 represents a halogen atom, a hydroxyl group, or an alkyl or alkoxy group having 1 to 5 carbon atoms (any hydrogen atom in the alkyl or alkoxy group may be substituted with a halogen atom). a represents an integer of 0 to 4, and when a is 2 or more, A2 may be the same or different. b and c represent integers of 1 or 2.)

[0056] [ka]

[0057] Preferred specific examples of the diamine represented by the above formula (w1) or (w2) include diamines represented by any of the following formulas (n3-1) to (n3-7) and diamines represented by any of the following formulas (n4-1) to (n4-6). [ka]

[0058] [ka]

[0059] For the purpose of improving printability, diamines having a carboxyl group (COOH group) or a hydroxyl group (OH group) can also be used. Specifically, 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, or 3,5-diaminobenzoic acid can be mentioned. Among them, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, or 3,5-diaminobenzoic acid is preferable. In addition, diamines represented by the following formulas [3b-1] to [3b-4], or diamines in which the amino group is a secondary amino group, can also be used.

[0060] [ka]

[0061] 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-, -CH2O-, -OCH2-, -COO-, -OCO-, -CON(CH3)- or N(CH3)CO-; m 1 and m 2 each independently represents an integer of 0 to 4, and m 1 +m 2 represents an integer of 1 to 4. In formula [3b-2], m 3 and m 4 Each independently represents an integer of 1 to 5. In formula [3b-3], Q 2 represents a linear or branched alkylene group having 1 to 5 carbon atoms; m 5 represents an integer of 1 to 5. In formula [3b-4], Q 3 and Q 4each independently represents a single bond, -CH2-, -C2H4-, -C(CH3)2-, -CF2-, -C(CF3)2-, -O-, -CO-, -NH-, -N(CH3)-, -CONH-, -NHCO-, -CHO-, -OCH2-, -COO-, -OCO, -CON(CH3)- or -N(CH3)CO-; m 6 represents an integer from 1 to 4.)

[0062] As the diamine component for obtaining the second polyamic acid, in addition to the above, the diamine used for obtaining the polymer (A) or a known diamine can be used. As the diamine component for obtaining the second polyamic acid, two or more kinds of diamines may be used in combination.

[0063] <Methods of producing polyamic acid, polyamic acid ester, and polyimide> The polyimide precursors, ie, polyamic acid ester, polyamic acid and polyimide, used in the present invention can be produced by known methods such as those described in WO2013 / 157586.

[0064] <Liquid crystal alignment agent> The liquid crystal alignment agent of the present invention may contain the polymer (A) and, if desired, a second polymer, and further may contain other polymers in addition to these. 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, poly(meth)acrylates, etc.

[0065] The liquid crystal aligning agent is used to prepare a liquid crystal alignment film, and takes 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 the above-mentioned polymer component and an organic solvent. In this case, the concentration (content) 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 and defect-free coating film, it is preferably 1% by mass or more, and from the viewpoint of storage stability of the solution, it is preferably 10% by mass or less. A particularly preferred polymer concentration is 2 to 8% by mass.

[0066] The organic solvent contained in the liquid crystal alignment agent is not particularly limited as long as it is a solvent (also called a good solvent) in which the polymer component is uniformly dissolved. Specific examples thereof include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylsulfoxide, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, etc. Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethylpropanamide, or γ-butyrolactone is preferred. The good solvent preferably accounts for 20 to 99% by mass, more preferably 20 to 90% by mass, and particularly preferably 30 to 80% by mass of the entire solvent contained in the liquid crystal aligning agent.

[0067] In addition, the organic solvent contained in the liquid crystal alignment agent is preferably a mixed solvent that uses a solvent (also called a poor solvent) that improves the coating property and the surface smoothness of the coating film when applying the liquid crystal alignment agent in addition to a good solvent. Specific examples of the poor solvent 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, 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-butoxyethoxy) 1-propanol, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, 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, diisobutyl ketone (2,6-dimethyl-4-heptanone), and the like.

[0068] Among these, the poor solvent is preferably diisobutyl carbinol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone.

[0069] Preferred combinations of good and poor solvents 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 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 are preferably 1 to 80% by mass, more preferably 10 to 80% by mass, and particularly preferably 20 to 70% by mass of the total solvent contained in the liquid crystal alignment agent. The type and content of such solvents are appropriately selected depending on the coating device, coating conditions, coating environment, etc. of the liquid crystal alignment agent.

[0070] The liquid crystal alignment agent of the present invention may additionally contain components other than the polymer component and the organic solvent. Such additional components include an adhesion assistant for increasing 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 material for adjusting the dielectric constant or electrical resistance of the liquid crystal alignment film, etc.

[0071] 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 represented by the following formula (e) (hereinafter these are also collectively referred to as compound (C)). [ka] (R 71 is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH2-OH". 72 and R 73 are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH2-OH". * indicates a bond. A represents an organic group having a valence of (m+n) and an aromatic ring. m represents an integer of 1 to 6, and n represents an integer of 0 to 4.)

[0072] Specific examples of compounds having an oxiranyl group include compounds having two or more oxiranyl groups, such as the compounds described in

[0037] of JP-A-10-338880 and compounds having a triazine ring skeleton described in WO2017 / 170483. Among these, 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 any of the following formulas (r-1) to (r-3), are particularly preferred. [ka]

[0073] Specific examples of the compound having an oxetanyl group include compounds having two or more oxetanyl groups described in

[0170] to

[0175] of WO2011 / 132751.

[0074] Specific examples of compounds having a protected isocyanate group include compounds having two or more protected isocyanate groups described in

[0046] to

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

[0119] to

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

[0075] Specific examples of compounds having a protected isothiocyanate group include compounds having two or more protected isothiocyanate groups described in JP 2016-200798 A. Specific examples of compounds having a group containing an oxazoline ring structure include compounds containing two or more oxazoline structures described in

[0115] of JP-A-2007-286597.

[0076] Specific examples of the compound having a group containing a Meldrum's acid structure include compounds having two or more Meldrum's acid structures described in WO2012 / 091088. Specific examples of the compound having a cyclocarbonate group include the compounds described in WO2011 / 155577. Examples of the alkyl group having 1 to 3 carbon atoms for R1, R2, and R3 in the group represented by the above formula (d) include a methyl group, an ethyl group, and a propyl group.

[0077] Specific examples of the compound having a group represented by the above formula (d) include compounds having two or more groups represented by the above formula (d) described in WO2015 / 072554 and JP 2016-118753 A

[0058] , compounds described in JP 2016-200798 A, etc. Among these, compounds represented by any of the following formulas (hd-1) to (hd-8) are preferred.

[0078] [ka]

[0079] Examples of the (m+n)-valent organic group having an aromatic ring in A of the above 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 above alkylene group, and a divalent or trivalent cyclohexane ring. Any hydrogen atom of the alkylene group may be substituted with an organic group such as a fluorine atom or a trifluoromethyl group. Specific examples include compounds described in WO2010 / 074269. Preferred specific examples include any of the following formulae (e-1) to (e-9).

[0080] [ka]

[0081] The above compounds are examples of crosslinkable compounds, and are not limited thereto. For example, the components other than those described above are disclosed in

[0105] to

[0116] of WO2015 / 060357. In addition, the crosslinkable compounds contained in the liquid crystal aligning agent of the present invention may be combined in two or more kinds. 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 viewpoints of proceeding with the crosslinking reaction to exhibit the intended effect and minimizing the occurrence of AC afterimages.

[0082] 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-trimethoxysilylpropyl. 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. The amount of these silane coupling agents used 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.

[0083] <Method of manufacturing liquid crystal alignment film> The liquid crystal alignment film using the liquid crystal aligning agent of the present invention can be produced by using the above-mentioned liquid crystal aligning agent of the present invention by a known method for obtaining a liquid crystal alignment film from a liquid crystal aligning agent. In particular, a liquid crystal alignment film using the liquid crystal aligning agent of the present invention can be efficiently produced by sequentially carrying out the following steps (1), (2), (3), and preferably step (4).

[0084] <Process (1)> This is a process of applying the liquid crystal alignment agent of the present invention onto a substrate. The substrate to which the liquid crystal alignment agent is applied is not particularly limited as long as it is a highly transparent substrate, and glass substrates, silicon nitride substrates, plastic substrates such as acrylic substrates and polycarbonate substrates, etc. can also be used. In this case, it is preferable to use a substrate on which an ITO electrode for driving the liquid crystal is formed, from the viewpoint of simplifying the process. In addition, in a reflective liquid crystal display element, one of the substrates can be an opaque one such as a silicon wafer, and in this case, a light-reflecting material such as aluminum can also be used for the electrode. Industrially, the liquid crystal alignment agent is generally applied by screen printing, offset printing, flexographic printing, inkjet printing, etc. Other application methods include a dip method, a roll coater method, a slit coater method, a spinner method, a spray method, etc., and these may be used depending on the purpose.

[0085] <Process (2)> Step (2) is a step of heating the coating film of the liquid crystal alignment agent obtained in step (1). After the liquid crystal alignment agent is applied on the substrate, the solvent can be evaporated or the amic acid or amic acid ester in the polymer can be thermally imidized by a heating means such as a hot plate, a heat circulation type oven, or an IR (infrared) type oven. The drying and baking steps after the application of the liquid crystal alignment agent can be performed at any temperature and time, and may be performed multiple times. The temperature for removing the organic solvent of the liquid crystal alignment agent can be, for example, 40 to 150°C. From the viewpoint of shortening the process, it may be performed at 40 to 120°C. The baking time is not particularly limited, but may be 1 to 10 minutes or 1 to 5 minutes. When the amic acid or amic acid ester in the polymer is thermally imidized, the polymer can be baked at, for example, 190 to 250°C or 200 to 240°C after the step of removing the organic solvent. The baking time is not particularly limited, but may be 5 to 40 minutes or 5 to 30 minutes.

[0086] <Process (3)> Step (3) is a step of irradiating the film obtained in step (2) with polarized ultraviolet light. The wavelength of the ultraviolet light is preferably 200 to 400 nm, more preferably 200 to 300 nm. In order to improve the liquid crystal alignment, the substrate coated with the liquid crystal alignment film may be irradiated with ultraviolet light while being heated at 50 to 250°C. The dose of the radiation is 1 to 10,000 mJ / cm. 2 is preferable, and 100 to 5,000 mJ / cm 2 The liquid crystal alignment film thus prepared can stably align liquid crystal molecules in a certain direction. The higher the extinction ratio of the polarized UV light, the higher the anisotropy that can be imparted, which is preferable. Specifically, the extinction ratio of the linearly polarized UV light is preferably 10:1 or more, and more preferably 20:1 or more.

[0087] <Process (4)> Step (4) is a step of baking the film obtained in step (3) at 100° C. or higher and at a temperature higher than that in step (2). The baking temperature is not particularly limited as long as it is 100° C. or higher and higher than the baking temperature in step (2), but is preferably 150 to 300° C., more preferably 150 to 250° C., and even more preferably 200 to 250° C. The baking time is preferably 5 to 120 minutes, more preferably 5 to 60 minutes, and even more preferably 5 to 30 minutes. The thickness of the liquid crystal alignment film after baking is preferably 5 to 300 nm, more preferably 10 to 200 nm, since if it is too thin, the reliability of the liquid crystal display element may decrease.

[0088] Furthermore, after carrying out either the above step (3) or (4), the obtained liquid crystal alignment film can be subjected to a contact treatment using water and / or a solvent. The solvent used in the contact treatment is not particularly limited as long as it dissolves the decomposition product generated from the liquid crystal alignment film by irradiation with ultraviolet light. 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. Among them, water, 2-propanol, 1-methoxy-2-propanol, and ethyl lactate are preferred from the viewpoint of versatility and solvent safety. Water, 1-methoxy-2-propanol, and ethyl lactate are more preferred. Two or more types of solvents may be combined.

[0089] The above-mentioned contact treatment, that is, the method of treating the liquid crystal alignment film irradiated with polarized ultraviolet light with water or a solvent, includes immersion treatment and spray treatment (also called spray treatment). The treatment time in these treatments is preferably 10 seconds to 1 hour from the viewpoint of efficiently dissolving the decomposition products generated from the liquid crystal alignment film by ultraviolet light. In particular, immersion treatment for 1 to 30 minutes is preferred. The solvent during the above-mentioned contact treatment may be at room temperature or heated, and is preferably 10 to 80°C. In particular, 20 to 50°C is preferred. In addition, from the viewpoint of the solubility of the decomposition products, ultrasonic treatment or the like may be performed as necessary.

[0090] After the contact treatment, it is preferable to rinse the liquid crystal alignment film with a low boiling point solvent such as water, methanol, ethanol, 2-propanol, acetone, or methyl ethyl ketone (also called rinsing). Either rinsing or baking may be performed, or both may be performed. The baking temperature is preferably 150 to 300°C, more preferably 180 to 250°C, and more preferably 200 to 230°C. The baking time is preferably 10 seconds to 30 minutes, and more preferably 1 to 10 minutes.

[0091] The liquid crystal alignment film of the present invention is suitable as a liquid crystal alignment film for a liquid crystal display element of a horizontal electric field type such as an IPS type or an FFS type, and is particularly useful as a liquid crystal alignment film for a liquid crystal display element of an FFS type. The liquid crystal display element is obtained by obtaining a substrate with a liquid crystal alignment film obtained from a liquid crystal alignment agent, and then producing a liquid crystal cell by a known method, and using the liquid crystal cell. As an example of a method for fabricating a liquid crystal cell, a liquid crystal display element having a passive matrix structure will be described below. However, a liquid crystal display element having an active matrix structure in which a switching element such as a TFT (Thin Film Transistor) is provided in each pixel portion constituting an image display may also be used.

[0092] Specifically, transparent glass substrates are prepared, and a common electrode is provided on one substrate, and a segment electrode is provided on the other substrate. These electrodes may be, for example, ITO electrodes, and are patterned to display a desired image. Next, an insulating film is provided on each substrate so as to cover the common electrode and the segment electrode. The insulating film may be, for example, a SiO2-TiO2 film formed by the sol-gel method. Next, a liquid crystal alignment film is formed on each substrate, and one substrate is superimposed on the other substrate so that the liquid crystal alignment film faces each other, and the periphery is bonded with a sealant. In order to control the gap between the substrates, a spacer is usually mixed into the sealant, and it is also preferable to scatter spacers for controlling the gap between the substrates on the inner surface where the sealant is not provided. An opening is provided in a part of the sealant so that liquid crystal can be filled from the outside. Next, a liquid crystal material is injected into the space surrounded by the two substrates and the sealant through the opening provided in the sealant, and then the opening is sealed with an adhesive. For the injection, a vacuum injection method or a method utilizing capillary action in the atmosphere may be used. The liquid crystal material may be either a positive type liquid crystal material or a negative type liquid crystal material. Next, a polarizing plate is installed. Specifically, a pair of polarizing plates is attached to the surface of the two substrates opposite to the liquid crystal layer.

[0093] As described above, by using the manufacturing method of the present invention, it is possible to suppress the occurrence of image retention due to long-term AC driving in liquid crystal display elements of IPS driving type or FFS driving type. In addition, by removing the organic solvent at 40 to 150°C in step (2) and then carrying out step (3), a liquid crystal alignment film can be obtained with fewer steps than in the past. The liquid crystal alignment agent of the present invention can be particularly preferably used in a manufacturing method of a liquid crystal alignment film including a step of removing the organic solvent at 40 to 150°C in step (2) and then carrying out step (3).

[0094] As described above, by using the liquid crystal alignment agent of the present invention, it is possible to obtain a liquid crystal alignment film with little residual DC-derived afterimage or AC afterimage and high seal adhesion. In particular, it is possible to obtain a liquid crystal display element with excellent contrast in which the brightness variation in the plane during black display is suppressed, and a liquid crystal display element with good display quality can be obtained. EXAMPLES

[0095] The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. The abbreviations of compounds and the measuring methods of each property are as follows. (solvent) NMP: N-methyl-2-pyrrolidone, GBL: γ-butyrolactone, BCS: butyl cellosolve; (Diamine) DA-1 to DA-4: Compounds represented by the following formulas (DA-1) to (DA-4), respectively: (Tetracarboxylic acid dianhydride) CA-1 and CA-2: Compounds represented by the following formulas (CA-1) and (CA-2), respectively (Additives) C-1: A compound represented by the following formula (C-1): C-2: 2,2'-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane S-1: a compound represented by the following formula (S-1):

[0096] [ka]

[0097] [ka]

[0098] [ka]

[0099] <Viscosity measurement> Measurements were performed at 25°C using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.) with a sample volume of 1.1 mL and a cone rotor TE-1 (1°34', R24).

[0100] <Measurement of imidization rate> 20 mg of polyimide powder was placed in an NMR sample tube (NMR sampling tube standard, φ5 (Kusano Scientific Co., Ltd.)), deuterated dimethyl sulfoxide (DMSO-d6, 0.05% TMS (tetramethylsilane) mixture) (0.53 mL) was added, and the mixture was completely dissolved by ultrasonication. This solution was measured by 500 MHz proton NMR using an NMR measurement device (JNW-ECA500) (JEOL Datum Co., Ltd.). The imidization rate was calculated by the following formula using the proton peak integrated value of this proton and the proton peak integrated value of the proton peak derived from the NH group of the amic acid that appears around 9.5 ppm to 10.0 ppm. Imidization rate (%) = (1-α·x / y) × 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%).

[0101] [Polymer synthesis example] The following are examples of synthesizing polyamic acid and polyimide. Note that PI stands for polyimide.

[0102] <Synthesis Example 1> 7.33 g (0.03 mol) of DA-1 was weighed out into a 200 mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 99.1 g of NMP was added and dissolved by stirring while supplying nitrogen. 6.19 g (0.028 mol) of CA-1 was added while stirring this diamine solution, and the mixture was stirred at 40°C for 24 hours to obtain a polyamic acid solution (A-1) (viscosity: 107 mPa s).

[0103] <Synthesis Example 2> 4.10g (0.0168mol) of DA-1 and 8.32g (0.0392mol) of DA-3 were weighed out into a 200mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 176g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. 11.6g (0.0518mol) of CA-1 was added while stirring this diamine solution, and the mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (A-2) (viscosity: 219mPa s).

[0104] <Synthesis Example 3> 6.37g (0.03mol) of DA-3 was weighed out into a 100mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, and 92.3g of NMP was added and dissolved by stirring while supplying nitrogen. 6.22g (0.0278mol) of CA-1 was added while stirring this diamine solution, and the mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (A-3) (viscosity: 347mPa s).

[0105] <Synthesis Example 4> 2.05g (0.0084mol) of DA-1 and 4.16g (0.0196mol) of DA-3 were weighed out into a 100mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 88.6g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. 5.52g (0.0246mol) of CA-1 and 0.35g (0.0014mol) of CA-2 were added while stirring this diamine solution, and the mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (A-4) (viscosity: 213mPa s).

[0106] <Synthesis Example 5> 3.23g (0.0084mol) of DA-2 and 4.16g (0.0196mol) of DA-3 were weighed out into a 200mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 97.3g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. 5.52g (0.0246mol) of CA-1 and 0.35g (0.0014mol) of CA-2 were added while stirring this diamine solution, and the mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (A-5) (viscosity: 198mPa·s).

[0107] <Synthesis Example 6> In a 200mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 1.37g (0.0056mol) of DA-1, 4.16g (0.0196mol) of DA-3, and 1.56g (0.0028mol) of DA-4 were weighed out, 95.1g of NMP was added, and the mixture was dissolved by stirring while supplying nitrogen. While stirring this diamine solution, 5.52g (0.0246mol) of CA-1 and 0.35g (0.0014mol) of CA-2 were added, and the mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (A-6) (viscosity: 224mPa·s).

[0108] <Synthesis Example 7> 1.37g (0.0056mol) of DA-1, 4.16g (0.0196mol) of DA-3, and 1.56g (0.0028mol) of DA-4 were weighed out into a 200mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 95.3g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. 5.21g (0.0232mol) of CA-1 and 0.700g (0.0028mol) of CA-2 were added while stirring this diamine solution, and the mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (A-7) (viscosity: 177mPa·s).

[0109] <Synthesis Example 8> 1.37g (0.0056mol) of DA-1, 4.16g (0.0196mol) of DA-3, and 1.56g (0.0028mol) of DA-4 were weighed into a 200mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 95.6g of NMP was added, and the mixture was stirred and dissolved while supplying nitrogen. 4.90g (0.0218mol) of CA-1 and 1.05g (0.0042mol) of CA-2 were added while stirring this diamine solution, and the mixture was stirred at 40℃ for 24 hours to obtain a polyamic acid solution (A-8) (viscosity: 176mPa·s).

[0110] <Synthesis Example 9> 35g (0.0093mol) of the obtained polyamic acid solution (A-1) was taken in a 100mL four-neck flask equipped with a stirrer and a nitrogen inlet tube, 11.7g of NMP was added, and the mixture was stirred for 30 minutes. 2.84g of acetic anhydride (3 equivalents relative to the molar amount of polyamic acid) and 0.73g of pyridine (equivalent to the molar amount of polyamic acid) were added to the obtained polyamic acid solution, and the mixture was heated at 50°C for 3 hours to perform chemical imidization. The obtained reaction solution was poured into 150ml of methanol while stirring, and the precipitate was filtered off. The same operation was carried out twice to wash the resin powder, and then the resin powder was dried at 60°C for 12 hours to obtain a polyimide resin powder. The imidization rate of this polyimide resin powder was 71%. 3.60 g of the obtained polyimide resin powder was placed in a 100 ml Erlenmeyer flask, 26.4 g of NMP was added so that the solid concentration was 12%, and the mixture was stirred at 70° C. for 24 hours to dissolve the polyimide resin, thereby obtaining a polyimide solution (A-1-PI).

[0111] <Synthesis Examples 10 to 16> The same procedure as in Synthesis Example 9 was used except that the raw materials shown in Table 1 below were used. The specifications of the polyimides obtained in Synthesis Examples 10 to 16 are shown in Table 1 together with those of Synthesis Example 9. [Table 1]

[0112] The numbers in parentheses in Table 1 indicate the blending ratio (parts by mole) of each compound relative to 100 parts by mole of the total amount of tetracarboxylic acid derivatives used in the synthesis for the tetracarboxylic acid components, and the blending ratio (parts by mole) of each compound relative to 100 parts by mole of the total amount of diamines used in the synthesis for the diamine components. The numbers in parentheses indicate the blending ratio (parts by mass) of each organic solvent relative to 100 parts by mass of the total amount of organic solvents contained in the polyamic acid solution or polyimide solution.

[0113] [Preparation of liquid crystal alignment agent] <Comparative Example 1> 7.5 g of polyimide solution (A-1-PI) was weighed out into a 20 ml sample tube containing a stirrer, and 2.23 g of NMP, 5.10 g of GBL, 4.0 g of BCS, 0.90 g of GBL solution containing 1 wt% of S-1, and 0.27 g of NMP solution containing 10 wt% of C-1 were added and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (R1).

[0114] <Example 1> In a 20 ml sample tube containing a stirrer, 7.5 g of polyimide solution (A-4-PI) was taken, and 2.23 g of NMP, 5.10 g of GBL, 4.0 g of BCS, 0.90 g of GBL solution containing 1 wt% of S-1, and 0.27 g of NMP solution containing 10 wt% of C-1 were added, and stirred with a magnetic stirrer for 30 minutes to obtain a liquid crystal alignment agent (1).

[0115] <Examples 2 to 6, Comparative Example 3> In Examples 2 to 6 and Comparative Example 3, each liquid crystal alignment agent was obtained in the same manner as in Comparative Example 1 and Example 1, except that each polyimide solution, additive, and organic solvent listed in the following Table 2 were used. The specifications of each obtained liquid crystal alignment agent are shown in Table 1 together with the liquid crystal alignment agents of Example 1 and Comparative Example 1.

[0116] [Table 2] The numbers in parentheses indicate the blending ratio (mass %) of each component relative to 100 parts by mass of the total amount of the liquid crystal alignment agent.

[0117] <Preparation of Liquid Crystal Display Element> A substrate with electrodes was prepared. The substrate was a glass substrate with a size of 30 mm x 35 mm and a thickness of 0.7 mm. An IZO electrode with a solid pattern was formed on the substrate as the first layer, which constituted the counter electrode. A SiN (silicon nitride) film formed by CVD was formed as the second layer on the first layer of the counter electrode. The thickness of the second layer of the SiN film was 500 nm, and it functions as an interlayer insulating film. A comb-shaped pixel electrode formed by patterning the IZO film as the third layer was arranged on the second layer of the SiN film, forming two pixels, the first pixel and the second pixel. The size of each pixel was 10 mm in length and about 5 mm in width. At this time, the first layer of the counter electrode and the third layer of the pixel electrode were electrically insulated by the action of the second layer of the SiN film.

[0118] The pixel electrode in the third layer has a comb-like shape composed of multiple electrode elements arranged in a "L" shape with a bent central portion. The width of each electrode element in the short direction is 3 μm, and the distance between the electrode elements is 6 μm. Since the pixel electrode forming each pixel is composed of multiple electrode elements arranged in a "L" shape with a bent central portion, the shape of each pixel is not rectangular, but has a shape similar to a bold "L" shape that is bent in the center like the electrode elements. Each pixel is divided into upper and lower parts by the central bend, and has a first region above the bent part and a second region below the bent part.

[0119] A liquid crystal alignment agent filtered through a filter with an average pore size of 1.0 μm was spin-coated onto the surface of each of the above-mentioned electrode-attached substrate and a glass substrate having a columnar spacer with a height of 4 μm and an ITO film formed on the back surface, and then dried on a hot plate at 80° C. for 2 minutes. After that, linearly polarized ultraviolet light with an extinction ratio of 26:1 and a wavelength of 254 nm was irradiated on the coating surface through a polarizer at 150 to 350 mJ / cm. 2 The coating was then irradiated and then baked in a hot air circulating oven at 230° C. for 30 minutes to obtain substrates with a liquid crystal alignment film having a thickness of 100 nm. Next, a sealant was printed on one of the pair of glass substrates with liquid crystal alignment film, and the other substrate was attached so that the liquid crystal alignment film faces each other, and the sealant was cured to prepare an empty cell. Liquid crystal MLC-3019 (Merck) was injected into this empty cell by a reduced pressure injection method, and the injection port was sealed to obtain an FFS drive liquid crystal cell. The obtained liquid crystal cell was then heated at 120°C for 1 hour and left overnight before being used for evaluation.

[0120] [evaluation] <Evaluation of liquid crystal alignment> Using liquid crystal cells before the ISO treatment, those with initial flow alignment were rated as "bad" and those without initial flow alignment were rated as "good."

[0121] <Evaluation of seal adhesion> [Sample preparation] The liquid crystal alignment agent prepared above was applied by spin coating to an ITO substrate of 30 mm x 40 mm. After drying for 2 minutes on a hot plate at 80 ° C, the coating surface was irradiated with 254 nm ultraviolet light through a polarizing plate, and then baked for 20 minutes in a hot air circulation oven at 230 ° C to form a coating film with a thickness of 100 nm. Two substrates obtained in this way were prepared, and 4 μm bead spacers were applied to the liquid crystal alignment film surface of one substrate, and then a sealant (XN-1500T manufactured by Kyoritsu Chemical Industry Co., Ltd.) was dropped. Next, the liquid crystal alignment film surface of the other substrate was placed inside, and the substrates were laminated so that the overlap width was 1 cm. At that time, the amount of the sealant dropped was adjusted so that the diameter of the sealant after lamination was 3 mm. 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.

[0122] [Seal adhesion measurement] The sample substrates prepared above were fixed at the ends of the top and bottom substrates in a bench-top precision universal testing machine (AGS-X 500N, manufactured by Shimadzu Corporation), and the strength (N) at the time of peeling was measured by pressing the substrate from the top center of the substrate. This peel strength (N) was calculated based on the adhesive area (mm 2 ) normalized by (peel strength (N) / adhesive area (mm 2)) for each sample was compared with the seal adhesion (N / mm 2 ) and the seal adhesion is 4N / mm 2 A value greater than 4N / mm was evaluated as "good". 2 The following cases were rated as "poor".

[0123] [Table 3] [Industrial Applicability]

[0124] The liquid crystal aligning agent of the present invention is useful for forming a liquid crystal alignment film in a wide range of liquid crystal display elements, such as those using the IPS driving method or the FFS driving method. The entire contents of the specification, claims, drawings, and abstract of Japanese Patent Application No. 2019-034305, filed on February 27, 2019, are hereby incorporated by reference as the disclosure of the specification of the present invention.

Claims

1. A liquid crystal aligning agent comprising a polymer (A) having a repeating unit represented by the following formula (3) and a repeating unit represented by the following formula (5): 【Chemistry 1】 (R in formula (3) ３１ From R ３４ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. ３１ From R ３４ At least one of Y represents a group other than a hydrogen atom as defined above. ３ represents a divalent organic group represented by the following formula (I): 【Chemistry 2】 (* represents a bond.) 【Chemistry 3】 (R ５１ From R ５４ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. ５１ From R ５４ At least one of Y represents a group other than a hydrogen atom as defined above. ５ each independently represents a divalent organic group having a partial structure represented by the following formula (J-1), or a divalent organic group represented by the following formula (J-2). 【Chemistry 4】 (Q ５ is a single bond, -(CH ２ ) ｎ -(n is an integer from 1 to 20), or -(CH ２ ) ｎ Any of -CH ２ -O-, -COO-, -OCO-, -NQ, etc., provided that - is not adjacent to each other. ９ --, --NQ ９ CO-, -CONQ ９ --, --NQ ９ CONQ １０ --, --NQ ９ It is a group that can be replaced by COO- or -OCOO-. ９ and Q. １０ Each of Q independently represents a hydrogen atom or a monovalent organic group. ６ , Q ７ are each independently -H, -NHD, -N(D) ２ , a group having -NHD, or -N(D) ２ Q represents a group having the formula: ８ -NHD, -N(D) ２ , a group having -NHD, or -N(D) ２ D represents a carbamate protecting group. ５ , Q ６ and Q. ７ At least one of the groups has a carbamate-based protecting group. *1 represents a bond.)

2. Q ５ However, (CH ２ ) ｎ Any of -CH ２ -NQ under the condition that - is not adjacent to each other ９ --, --NQ ９ CO- or -CONQ ９ The liquid crystal aligning agent according to claim 1, wherein the aryl group is a group substituted with -.

3. 3. The liquid crystal aligning agent according to claim 1, wherein the polymer (A) is a polyimide having an imide ratio of 71% or more.

4. Further, the liquid crystal aligning agent according to any one of claims 1 to 3, which contains 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 represented by the following formula (e). 【Chemistry 5】 (R ７１ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ２ -OH". ７２ and R ７３ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ２ -OH". * indicates a bond. A represents an (m+n)-valent organic group having an aromatic ring. m represents an integer of 1 to 6, and n represents an integer of 0 to 4.

5. Seal adhesion is 4N / mm ２ The liquid crystal aligning agent according to any one of claims 1 to 4, wherein a liquid crystal alignment film having a size larger than

6. A liquid crystal alignment film comprising a polymer (A) having a repeating unit represented by the following formula (3) and a repeating unit represented by the following formula (5): 【Chemistry 6】 (R in formula (3) ３１ From R ３４ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. ３１ From R ３４ At least one of Y represents a group other than a hydrogen atom as defined above. ３ represents a divalent organic group represented by the following formula (I): 【Chemistry 7】 (* represents a bond.) 【Chemistry 8】 (R ５１ From R ５４ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. ５１ From R ５４ At least one of Y represents a group other than a hydrogen atom as defined above. ５ each independently represents a divalent organic group having a partial structure represented by the following formula (J-1), or a divalent organic group represented by the following formula (J-2). 【Chemistry 9】 (Q ５ is a single bond, -(CH ２ ) ｎ -(n is an integer from 1 to 20), or -(CH ２ ) ｎ Any of -CH ２ -O-, -COO-, -OCO-, -NQ, etc., provided that - is not adjacent to each other. ９ --, --NQ ９ CO-, -CONQ ９ --, --NQ ９ CONQ １０ --, --NQ ９ It is a group that can be replaced by COO- or -OCOO-. ９ and Q. １０ Each of Q independently represents a hydrogen atom or a monovalent organic group. ６ , Q ７ are each independently -H, -NHD, -N(D) ２ , a group having -NHD, or -N(D) ２ Q represents a group having the formula: ８ -NHD, -N(D) ２ , a group having -NHD, or -N(D) ２ D represents a carbamate protecting group. ５ , Q ６ and Q. ７ At least one of the groups has a carbamate-based protecting group. *1 represents a bond.)

7. Q ５ However, (CH ２ ) ｎ Any of -CH ２ -NQ under the condition that - is not adjacent to each other ９ --, --NQ ９ CO- or -CONQ ９ The liquid crystal alignment film according to claim 6, wherein the aryl group is a group substituted with -.

8. 8. The liquid crystal alignment film according to claim 6, wherein the polymer (A) is a polyimide having an imide ratio of 71% or more.

9. Further, 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 represented by the following formula (e) (hereinafter, these are also collectively referred to as compound (C)). The liquid crystal alignment film according to any one of claims 6 to 8. 【Chemistry 10】 (R ７１ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ２ -OH". ７２ and R ７３ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ２ -OH". * indicates a bond. A represents an (m+n)-valent organic group having an aromatic ring. m represents an integer of 1 to 6, and n represents an integer of 0 to 4.

10. Seal adhesion is 4N / mm ２ The liquid crystal alignment film according to any one of claims 6 to 9, wherein

11. A method for producing a liquid crystal alignment film, comprising the following steps (1) to (3): Step (1): A step of applying a liquid crystal aligning agent containing a polymer (A) having a repeating unit represented by the following formula (3) and a repeating unit represented by the following formula (5) onto a substrate. Step (2): A step of heating the coating film of the liquid crystal alignment agent obtained in step (1). Step (3): A step of irradiating the film obtained in step (2) with polarized ultraviolet light. 【Chemistry 11】 (R in formula (3) ３１ From R ３４ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. ３１ From R ３４ At least one of Y represents a group other than a hydrogen atom as defined above. ３ represents a divalent organic group represented by the following formula (I): 【Chemistry 12】 (* represents a bond.) 【Chemistry 13】 (R ５１ From R ５４ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group, and may be the same or different. ５１ From R ５４ At least one of Y represents a group other than a hydrogen atom as defined above. ５ each independently represents a divalent organic group having a partial structure represented by the following formula (J-1), or a divalent organic group represented by the following formula (J-2). 【Chemistry 14】 (Q ５ is a single bond, -(CH ２ ) ｎ -(n is an integer from 1 to 20), or -(CH ２ ) ｎ Any of -CH ２ -O-, -COO-, -OCO-, -NQ, etc., provided that - is not adjacent to each other. ９ --, --NQ ９ CO-, -CONQ ９ --, --NQ ９ CONQ １０ --, --NQ ９ It is a group that can be replaced by COO- or -OCOO-. ９ and Q. １０ Each of Q independently represents a hydrogen atom or a monovalent organic group. ６ , Q ７ are each independently -H, -NHD, -N(D) ２ , a group having -NHD, or -N(D) ２ Q represents a group having the formula: ８ -NHD, -N(D) ２ , a group having -NHD, or -N(D) ２ D represents a carbamate protecting group. ５ , Q ６ and Q. ７ At least one of the groups has a carbamate-based protecting group. *1 represents a bond.)

12. Q ５ However, (CH ２ ) ｎ Any of -CH ２ -NQ under the condition that - is not adjacent to each other ９ --, --NQ ９ CO- or -CONQ ９ The method for producing a liquid crystal alignment film according to claim 11, wherein the aryl group is a group substituted with -.

13. The method for producing a liquid crystal alignment film according to claim 11 or 12, wherein the polymer (A) is a polyimide having an imide ratio of 71% or more.

14. Further, 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 represented by the following formula (e) (hereinafter, these are also collectively referred to as compound (C)). The method for producing a liquid crystal alignment film according to any one of claims 11 to 13. 【Chemistry 15】 (R ７１ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ２ -OH". ７２ and R ７３ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or "*-CH ２ -OH". * indicates a bond. A represents an (m+n)-valent organic group having an aromatic ring. m represents an integer of 1 to 6, and n represents an integer of 0 to 4.

15. The seal adhesion of the liquid crystal alignment film is 4N / mm. ２ The method for producing a liquid crystal alignment film according to any one of claims 11 to 14, wherein

16. The method for producing a liquid crystal alignment film according to any one of claims 11 to 15, further comprising the following step (4): Step (4): A step of baking the film obtained in step (3) at a temperature of 100° C. or higher and at a temperature higher than that in step (2).

17. In the step (2), the coating film of the liquid crystal alignment agent is heated at a temperature of 40 to 180° C.; The method for producing a liquid crystal alignment film according to any one of claims 11 to 16.

18. A liquid crystal display device comprising a liquid crystal alignment film obtained by the method for producing a liquid crystal alignment film according to any one of claims 11 to 17.

19. A liquid crystal display device comprising the liquid crystal alignment film according to any one of claims 6 to 10.

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