Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal element and its manufacturing method, polymer and diamine

Abstract

This invention provides a liquid crystal alignment agent, which yields a liquid crystal alignment film with high reliability and excellent narrow-line adhesion even under harsh conditions, a liquid crystal element, a method for manufacturing the same, a polymer, and a diamine. This invention incorporates a polymer (P) having a partial structure represented by formula (1) into the liquid crystal alignment agent. Wherein, R... 1 and R 2 Each is independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. X 1 Alkyl groups consisting of single bonds, 1 to 6 carbon atoms, -O-, -CH2-O-* 1 -O-(CH2) a -O-, -(CH2) b -COO-* 1 、-(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 a is an integer from 1 to 6. b is an integer from 0 to 6.

Description

Technical Field

[0001] This invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, a liquid crystal element, a polymer, and a diamine. Background Technology

[0002] Liquid crystal elements are used in a wide range of applications, from large display devices such as LCD TVs and information displays to small display devices such as smartphones and personal computers (PCs). With this diversification, there is a demand for high display quality in liquid crystal elements. As one of the ways to further improve the quality of liquid crystal elements, various characteristics of liquid crystal alignment films have been improved (for example, see Patent Document 1).

[0003] Patent Document 1 discloses the following: polyamic acid and polyimide are manufactured using a diamine having an acetophenone structure and a vertical alignment structure in the molecule; a liquid crystal alignment film is then fabricated using a liquid crystal alignment agent containing the manufactured polyimide. Thus, in the liquid crystal alignment film described in Patent Document 1, by irradiating with a long wavelength of 365 nm, a tilt angle of 85° to 89.5°, necessary for either polymer-stable alignment (PSA) or vertical alignment (VA), can be observed.

[0004] In mobile display devices such as smartphones or tablet PCs, narrow bezels are sought to increase the operating area of ​​the touchscreen while miniaturizing the display device. One method for achieving narrow bezels is known to be a method of bonding the substrates together by applying a sealant to the liquid crystal alignment film after forming a liquid crystal alignment film on the entire substrate surface (for example, see Patent Document 2).

[0005] [Existing Technical Documents]

[0006] [Patent Literature]

[0007] [Patent Document 1] International Publication No. 2017 / 030170

[0008] [Patent Document 2] Japanese Patent Application Publication No. 2013-109154 Summary of the Invention

[0009] [The problem the invention aims to solve]

[0010] With the increasing versatility of applications, it is envisioned that liquid crystal elements will be used in more demanding environments than before. As liquid crystal elements, it is required that they maintain performance even when used under harsh conditions. Specifically, they are required to have reliability that can withstand long-term use in high-temperature environments, or high reliability relative to high temperature and high humidity resistance.

[0011] When a sealant is applied to a liquid crystal alignment film for the purpose of narrowing the bezel of the liquid crystal element, there is a tendency for the liquid crystal alignment film to peel off from the substrate in the sealant area. In recent years, in order to further narrow the bezel, research has been conducted on reducing the width of the sealant (hereinafter also referred to as "seal width"). It is required that even when the substrates are bonded together with a narrowed seal width, the liquid crystal alignment film is not prone to peeling off from the substrate in the sealant area (hereinafter also referred to as "narrow line adhesion").

[0012] The present invention was made in view of the above circumstances, and its main objective is to provide a liquid crystal alignment agent that can produce a liquid crystal alignment film with high reliability and excellent narrow-line adhesion even when used under harsh conditions.

[0013] [Technical means to solve the problem]

[0014] To address the aforementioned problems, the inventors focused on introducing specific chromanone structures into polymers. Specifically, the present invention employs the following methods to solve the above-mentioned problems.

[0015] [1] A liquid crystal alignment agent comprising a polymer (P) having a partial structure represented by the following formula (1).

[0016] [Chemistry 1]

[0017]

[0018] (In equation (1), R) 1 and R 2 Each is independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. X 1 It is a single bond, an alkyl diyl group with 1 to 6 carbon atoms, -O-, or -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 a is an integer from 1 to 6. b is an integer from 0 to 6. 1" " indicates a bond with the benzene ring in equation (1). "*" indicates a bond.

[0019] [2] A liquid crystal alignment film formed using a liquid crystal alignment agent according to [1].

[0020] [3] A liquid crystal element comprising a liquid crystal alignment film according to [2].

[0021] [4] A method for manufacturing a liquid crystal element includes: a step of forming a coating by coating a liquid crystal alignment agent according to [1] onto each conductive film of a pair of substrates having a conductive film; a step of constructing a liquid crystal cell by arranging the pair of substrates having the coating on facing each other with the coating separated by a liquid crystal layer; and a step of irradiating the liquid crystal cell with light while applying a voltage between the conductive films.

[0022] [5] An aggregate having a partial structure represented by the formula (1).

[0023] [6] A diamine, represented by the following formula (2-1).

[0024] [Chemistry 2]

[0025]

[0026] (In equation (2-1), R) 1 and R 2 Each is independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. X 1 It is a single bond, an alkyl diyl group with 1 to 6 carbon atoms, -O-, or -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 a is an integer from 1 to 6. b is an integer from 0 to 6. 1 " represents the bond with the benzene ring in formula (2-1). Ar 1 It is a trivalent aromatic cyclic group.

[0027] [7] A diamine, represented by the following formula (2-2).

[0028] [Chemistry 3]

[0029]

[0030] (In equation (2-2), R) 1 and R2 Each is independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. X 1 It is a single bond, an alkyl diyl group with 1 to 6 carbon atoms, -O-, or -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 a is an integer from 1 to 6. b is an integer from 0 to 6. 1 " represents the bond with the benzene ring in equation (2-2). Ar 2 and Ar 4 Each is an independent divalent aromatic cyclic group. Ar 3 It is a trivalent aromatic cyclic group. X 2 and X 3 Each is independently a single bond, -O-, -CH2-, -CO-, -NR. 3 -、-COO-、-OCO-、-CONR 3 -or-NR 3 CO-. R 3 (It can be a hydrogen atom or a monovalent organic group.)

[0031] [The effects of the invention]

[0032] According to the liquid crystal alignment agent containing the polymer (P), a liquid crystal alignment film with high reliability and excellent narrow-line adhesion can be obtained even when used under harsh conditions. Detailed Implementation

[0033] The following provides a detailed description of matters related to the form disclosed herein. Furthermore, in this specification, the term "hydrocarbon group" encompasses chain-like hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. "Chain-like hydrocarbon group" refers to a straight-chain hydrocarbon group or a branched hydrocarbon group that consists only of a chain structure and does not contain a ring structure. It can be saturated or unsaturated. "Alicyclic hydrocarbon group" refers to a hydrocarbon group that contains only an alicyclic hydrocarbon structure as its ring structure and does not contain an aromatic ring structure. It is not necessary for it to consist only of an alicyclic hydrocarbon structure; it may also include a group with a chain structure in a portion thereof. "Aromatic hydrocarbon group" refers to a hydrocarbon group that contains an aromatic ring structure as its ring structure. It is not necessary for it to consist only of an aromatic ring structure; it may also include a chain structure or an alicyclic hydrocarbon structure in a portion thereof. The "main chain" of a polymer refers to the longest "trunk" portion of the atomic chain of the polymer. The "side chain" of a polymer refers to the branched portion from the "trunk" of the polymer. The term "organic radical" refers to an atomic group formed by removing any hydrogen atom from a carbon-containing compound (i.e., an organic compound).

[0034] <<Liquid Crystal Alignment Agent>>

[0035] The liquid crystal alignment agent disclosed herein contains a polymer (P) having a partial structure represented by the following formula (1).

[0036] [Chemistry 4]

[0037]

[0038] (In equation (1), R) 1 and R 2 Each is independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. X 1 It is a single bond, an alkyl diyl group with 1 to 6 carbon atoms, -O-, or -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 a is an integer from 1 to 6. b is an integer from 0 to 6. 1 " " indicates a bond with the benzene ring in equation (1). "*" indicates a bond.

[0039] <Polymer (P)>

[0040] In the above equation (1), in R 1 and R 2When the represented group is an alkyl group having 1 to 3 carbon atoms, the alkyl group can be linear or branched. Specific examples of alkyl groups having 1 to 3 carbon atoms include methyl, ethyl, n-propyl, and isopropyl. Among these, from the viewpoint of improving the narrow-line closeness of liquid crystal alignment films, R... 1 and R 2 The alkyl group represented is preferably methyl or ethyl, more preferably methyl.

[0041] R 1 and R 2 The radicals represented can all be hydrogen atoms, but from the viewpoint of making the obtained liquid crystal alignment film have better high temperature and high humidity resistance, it is preferable that at least one of them is an alkyl group having 1 to 3 carbon atoms, and more preferably R. 1 and R 2 All are alkyl groups having 1 to 3 carbon atoms. That is, R 1 and R 2 R is preferred 1 It is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R 2 It is an alkyl group having 1 to 3 carbon atoms, more preferably R. 1 and R 2 They are alkyl groups having 1 to 3 carbon atoms.

[0042] In X 1 When the represented group is an alkyldiyl group having 1 to 6 carbon atoms, the alkyldiyl group can be linear or branched. From the viewpoint of obtaining a liquid crystal element with good liquid crystal alignment, X 1 The alkyl diene represented is preferably linear. From the viewpoint of improving film density and polymer entanglement, as well as improving narrow-line tightness and reliability (especially reliability during long-term use under high-temperature environments (hereinafter also referred to as "long-term thermal reliability") and resistance to high temperature and humidity), X... 1 The alkyl diol represented preferably has 1 to 5 carbon atoms, more preferably 1 to 4, and particularly preferably 1 to 3. Furthermore, for the same reason, a and b are preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less.

[0043] As specific examples of the partial structure represented by the above formula (1), the partial structures represented by the following formulas (1-1) to (1-33) can be listed respectively.

[0044] [Chemistry 5]

[0045]

[0046] [Chemistry 6]

[0047]

[0048] [Chemistry 7]

[0049]

[0050] <Specific Forms of Aggregates (P)>

[0051] The main framework of the polymer (P) is not particularly limited, but from the viewpoint of good heat resistance or mechanical strength, affinity with liquid crystals, etc., it is preferably selected from at least one of the group consisting of polyamic acid, polyimide, polyamic acid ester, polyorganosiloxane and addition polymers. The polymer (P) may have the partial structure represented by the formula (1) at the end of the main chain or the partial structure represented by the formula (1). In terms of high incorporation rate of the partial structure represented by the formula (1) and easy adjustment of the incorporation amount of the partial structure represented by the formula (1), the polymer (P) is preferably a structural unit derived from a monomer that has the partial structure represented by the formula (1). Hereinafter, preferred examples of the polymer (P) will be described.

[0052] [Polyamic acid]

[0053] Polyamic acid (hereinafter also referred to as "polyamic acid (P)") as polymer (P) can be obtained by polymerization using monomers having a partial structure represented by the formula (1). Examples of methods for manufacturing polyamic acid (P) include: [1] a method of polymerizing a monomer containing a tetracarboxylic dianhydride having a partial structure represented by the formula (1); [2] a method of polymerizing a monomer containing a diamine (hereinafter also referred to as "specific diamine") having a partial structure represented by the formula (1). Of these, the method using a specific diamine is preferred in terms of ease of monomer synthesis.

[0054] (Tetracarboxylic acid dianhydride)

[0055] Examples of tetracarboxylic dianhydrides used in the synthesis of polyamic acid (P) include aliphatic tetracarboxylic dianhydrides and aromatic tetracarboxylic dianhydrides. Examples of aliphatic tetracarboxylic dianhydrides include chain tetracarboxylic dianhydrides and alicyclic tetracarboxylic dianhydrides.

[0056] Specific examples of them include 1,2,3,4-butanetetracarboxylic anhydride, etc.

[0057] Examples of alicyclic tetracarboxylic dianhydrides include: 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxylated cyclopentylacetic dianhydride, 5-(2,5-dioxotetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuran-3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 2,4,6,8-tetracarboxylated bicyclo[3.3.0]octane-2:4,6:8-dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride, etc.

[0058] Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 4,4'-(hexafluoroisopropylidene)phthalic anhydride, ethylene glycol dimethacrylate, and 4,4'-carbonyl phthalic anhydride. In addition, tetracarboxylic dianhydrides described in Japanese Patent Application Publication No. 2010-97188 may be used. One tetracarboxylic dianhydride may be used alone or in combination of two or more.

[0059] In terms of improving the solubility of the polymer and obtaining a liquid crystal alignment film exhibiting good electrical properties, the tetracarboxylic dianhydride used in the synthesis of polyamic acid is preferably an aliphatic tetracarboxylic dianhydride (i.e., at least one selected from the group consisting of chain tetracarboxylic dianhydrides and alicyclic tetracarboxylic dianhydrides), more preferably an alicyclic tetracarboxylic dianhydride. The amount of alicyclic tetracarboxylic dianhydride used is preferably 20 mol% or more, more preferably 40 mol% or more, and even more preferably 50 mol% or more, relative to the total amount of tetracarboxylic dianhydride used in the synthesis of polyamic acid (P).

[0060] (Diamine)

[0061] ·Specific diamine

[0062] The specific diamine used in the synthesis of polyamic acid (P) is not particularly limited as long as it has the partial structure represented by formula (1). The specific diamine may have the partial structure represented by formula (1) in the main chain or in the side chain. Preferably, at least one selected from the group consisting of compounds represented by formula (2-1) and compounds represented by formula (2-2) is used as the specific diamine.

[0063] [Chemistry 8]

[0064]

[0065] (In equations (2-1) and (2-2), Ar) 1 and Ar 3 Each is an independent trivalent aromatic cyclic group. Ar2 and Ar 4 Each is independently a divalent aromatic cyclic group. X 2 and X 3 Each is independently a single bond, -O-, -CH2-, -CO-, -NR. 3 -、-COO-、-OCO-、-CONR 3 -or-NR 3 CO-. R 3 It can be a hydrogen atom or a monovalent organic group. R 1 R 2 and X 1 (This has the same meaning as equation (1) above.)

[0066] In equations (2-1) and (2-2), Ar 1 and Ar 3 The trivalent aromatic ring group referred to is a group formed by removing three hydrogen atoms from the ring portion of a substituted or unsubstituted aromatic ring. Examples of such aromatic rings include: aromatic hydrocarbon rings such as benzene rings, biphenyl rings, naphthalene rings, and anthracene rings; and aromatic heterocycles such as pyridine rings and pyridazine rings. Among these, benzene rings and pyridine rings are preferred, and benzene rings are more preferred. Furthermore, in Ar... 1 and Ar 3 Substituents may also be introduced into the aromatic ring of the trivalent aromatic ring group. Examples of such substituents include: alkyl groups having 1 to 3 carbon atoms, alkoxy groups having 1 to 3 carbon atoms, halogen atoms, hydroxyl groups, cyano groups, nitro groups, carboxyl groups, etc.

[0067] Ar 2 and Ar 4 The divalent aromatic ring group represented is a group formed by removing two hydrogen atoms from the ring portion of a substituted or unsubstituted aromatic ring. As a specific example of the aromatic ring, Ar... 1 and Ar 3 The aromatic hydrocarbon rings and aromatic heterocycles illustrated in the description. Among these, benzene rings, biphenyl rings, naphthalene rings, and pyridine rings are preferred, more preferably benzene rings and pyridine rings, and even more preferably benzene rings. Furthermore, in Ar... 2 and Ar 4 The aromatic ring represented by the divalent aromatic ring group may also be introduced with substituents (e.g., alkyl groups having 1 to 3 carbon atoms, halogen atoms, etc.).

[0068] In R 3 When the represented group is a monovalent organic group, it is used as R 3 The monovalent organic groups represented can be listed as monovalent hydrocarbon groups having 1 to 10 carbon atoms, and monovalent thermally detachable groups. As R... 3Specific examples of monovalent hydrocarbon groups include alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 4 to 10 carbon atoms, aryl groups having 6 to 10 carbon atoms, and aralkyl groups having 6 to 10 carbon atoms. Among these, alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups, and phenyl groups are preferred, and alkyl groups having 1 to 3 carbon atoms are more preferred.

[0069] In R 3 In the case of a monovalent thermally detachable radical, R 3 The thermally detachable group is preferably a monovalent group that detaches upon heating during film formation. Specific examples of thermally detachable groups include: tert-butoxycarbonyl (Boc group), benzyloxycarbonyl, 1,1-dimethyl-2-haloethyloxycarbonyl, allyloxycarbonyl, 2-(trimethylsilyl)ethoxycarbonyl, 9-fluorenylmethyloxycarbonyl, etc. Among these, the Boc group is particularly preferred in terms of excellent thermal detachment and reduced residual amount of the detached structure in the film.

[0070] As specific examples of a particular diamine, the compounds represented by formula (2-1) may include, for example, the compounds represented by formulas (2-1-1) to (2-1-32) below; the compounds represented by formula (2-2) may include, for example, the compounds represented by formulas (2-2-1) to (2-2-4) below.

[0071] [Chemistry 9]

[0072]

[0073] [Chemistry 10]

[0074]

[0075] [Chemistry 11]

[0076]

[0077] [Chemistry 12]

[0078]

[0079] [Chemistry 13]

[0080]

[0081] [Chemistry 14]

[0082]

[0083] Specific diamines can be synthesized by a suitable combination of general organic chemistry methods. As an example of a synthetic method, the following approach can be described: synthesizing a dinitro intermediate having a nitro group in place of the primary amino group in formulas (2-1) and (2-2), and then amination of the nitro group of the obtained dinitro intermediate using a suitable reducing system.

[0084] The method for synthesizing the aforementioned dinitro intermediate is not particularly limited and can be suitably selected depending on the target compound. For example, a method can be described in which a dinitro compound having a haloalkyl, halogen, acyl chloride, or alkyl acyl chloride group is reacted with a specific compound having the ring structure and hydroxyl group of formula (2-1) or (2-2) in an organic solvent in the presence of a base catalyst (sodium hydroxide, triethylamine, potassium carbonate, etc.). However, the method for synthesizing the specific dinitro intermediate is not limited to those described above.

[0085] The reduction reaction of the dinitro intermediate is preferably carried out in an organic solvent using catalysts such as palladium on carbon, platinum oxide, zinc, iron, tin, nickel, platinum on carbon, and osmium on carbon. Examples of organic solvents used herein include ethyl acetate, toluene, tetrahydrofuran, and alcohols. Alternatively, two or more of these organic solvents may be used in combination. The synthetic procedures for the compounds represented by formula (2-1) and formula (2-2) are not limited to the methods described herein.

[0086] Other diamines

[0087] The diamine used in the synthesis of polyamic acid (P) may be only a specific diamine, but may also be used in combination with diamines that do not have the partial structure represented by formula (1) (hereinafter also referred to as "other diamines"). Examples of other diamines include aliphatic diamines, aromatic diamines, and diamino organosiloxanes. Examples of aliphatic diamines include chain diamines and alicyclic diamines.

[0088] Other specific examples of diamines include: m-phenylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, etc.

[0089] Examples of alicyclic diamines include: 1,4-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine), etc.

[0090] Aromatic diamines include: p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4-aminophenyl-4-aminobenzoate, 4,4'-diaminoazobenzene, 3,5-diaminobenzoic acid, 1,5-bis(4-aminophenoxy)pentane, 1,2-bis(4-aminophenoxy)ethane, 1,3-bis(4-aminophenoxy)propane, 1,6-bis(4-aminophenoxy)hexane, bis[2-(4-aminophenyl)ethyl]adipic acid, 2,6-diaminopyridine, 1,4-bis-(4-aminophenyl)piperazine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(triphenyl)-2-aminobenzene, etc. Main-chain diamines include fluoromethyl)-4,4'-diaminobiphenyl, 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-(phenylene diisopropylidene)bisaniline, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-[4,4'-propane-1,3-diylbis(piperidine-1,4-diyl)]diphenylamine, 4,4'-diaminobenzoylaniline, 4,4'-diaminostyrylbenzene, and 1,4-bis(4-aminophenyl)-piperazine.

[0091] Dodecyloxy-2,4-diaminobenzene, pentadecyloxy-2,4-diaminobenzene, hexadecyloxy-2,4-diaminobenzene, octadecyloxy-2,4-diaminobenzene, pentadecyloxy-2,5-diaminobenzene, octadecyloxy-2,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, 3,5-diaminobenzoic acid cholesterane Alkyl ester, 3,5-diaminobenzoic acid cholesterol, 3,5-diaminobenzoic acid lanosteryl ester, 3,6-bis(4-aminobenzoyloxy)cholestane, 3,6-bis(4-aminophenoxy)cholestane, 4-(4'-trifluoromethoxybenzoyloxy)cyclohexyl-3,5-diaminobenzoic acid ester, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane, 3,5-diaminobenzoic acid = 5ξ-cholestane-3-yl, and the following formula (E-1)

[0092] [Chemistry 15]

[0093]

[0094] (In formula (E-1), X) I and X II Each can be independently represented as a single bond, -O-, *-COO-, or *-OCO- (where "*" indicates a bond to the diaminophenyl side). R I It is an alkyldiyl group having 1 to 3 carbon atoms. R IIIt is a single bond or an alkyldiyl group having 1 to 3 carbon atoms. R III It can be an alkyl, alkoxy, fluoroalkyl, or fluoroalkoxy group having 1 to 20 carbon atoms. a is 0 or 1. b is an integer from 0 to 3. c is an integer from 0 to 2. d is 0 or 1. Where 1 ≤ a + b + c ≤ 3.

[0095] The compounds represented include side-chain diamines, etc.

[0096] Examples of diamino organosiloxanes include 1,3-bis(3-aminopropyl)-tetramethyldisiloxane, and other diamines described in Japanese Patent Application Publication No. 2010-97188 may also be used. In the synthesis of polyamic acid (P), one or more diamines may be used alone or in combination as other diamines.

[0097] In polyamic acid (P), the proportion of the partial structure represented by formula (1) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, relative to all diamine units contained in polyamic acid (P). Furthermore, the proportion of the partial structure represented by formula (1) is preferably 95 mol% or less, more preferably 90 mol% or less, and even more preferably 85 mol% or less, relative to all diamine units contained in polyamic acid (P). If the proportion of the partial structure represented by formula (1) in polyamic acid (P) is within the aforementioned range, improved narrow-line adhesion, long-term thermal reliability, and resistance to high temperature and humidity can be sufficiently obtained, and this is preferred in this respect.

[0098] Synthesis of polyamic acid

[0099] Polyamic acid (P) can be obtained by reacting the tetracarboxylic dianhydride described above with a diamine and, if necessary, a molecular weight adjuster. The preferred ratio of tetracarboxylic dianhydride to diamine used in the synthesis reaction of polyamic acid (P) is 0.2 to 2 equivalents relative to the amino group of the diamine.

[0100] Examples of molecular weight modifiers include: maleic anhydride, phthalic anhydride, itaconic anhydride, and other monoanhydrides; aniline, cyclohexylamine, n-butylamine, and other monoamine compounds; and phenyl isocyanate, naphthyl isocyanate, and other monoisocyanate compounds. The proportion of the molecular weight modifier used is preferably 20 parts by mass or less, relative to a total of 100 parts by mass of the tetracarboxylic dianhydride and diamine used.

[0101] The synthesis reaction of polyamic acid (P) is preferably carried out in an organic solvent. The preferred reaction temperature is -20°C to 150°C, and the preferred reaction time is 0.1 h to 24 h. Examples of organic solvents used in the reaction include: aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. Particularly preferred organic solvents are those selected from the group consisting of N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphoric triamine, m-cresol, xylenol, and halogenated phenols, or mixtures of these solvents with other organic solvents (e.g., butyl cellosolve, diethylene glycol diethyl ether, etc.). The amount (a) of the organic solvent used is preferably set such that the total amount (b) of the tetracarboxylic dianhydride and diamine is 0.1% to 50% by mass relative to the total amount (a+b) of the reaction solution.

[0102] A reaction solution is obtained by dissolving polyamic acid (P) in the manner described above. The reaction solution can be used directly for the preparation of a liquid crystal alignment agent, or it can be used for the preparation of a liquid crystal alignment agent after separating the polyamic acid (P) contained in the reaction solution.

[0103] (polyamide ester)

[0104] Polyamic acid esters (hereinafter also referred to as "polyamic acid esters (P)") as polymers (P) can be obtained, for example, by methods such as: [I] reacting polyamic acid (P) obtained by the synthesis reaction with an esterifying agent; [II] reacting a tetracarboxylic acid diester with a diamine containing a specific diamine; [III] reacting a tetracarboxylic acid diester dihalide with a diamine containing a specific diamine. The polyamic acid ester (P) contained in the liquid crystal alignment agent of this disclosure may have only an amide ester structure, or it may be a partial esterification with both an amide acid structure and an amide ester structure. The reaction solution obtained by dissolving polyamic acid ester (P) can be directly used in the preparation of the liquid crystal alignment agent, or it can be used in the preparation of the liquid crystal alignment agent after separating the polyamic acid ester (P) contained in the reaction solution.

[0105] (Polyimide)

[0106] Polyimide (hereinafter also referred to as "polyimide (P)") as polymer (P) can be obtained, for example, by dehydrating and ring-closing polyamic acid (P) synthesized in the manner described above, and then imidizing it. Polyimide (P) can be a fully imidized product obtained by dehydrating and ring-closing all the amic acid structures possessed by the polyamic acid (P) as its precursor, or it can be a partially imidized product obtained by dehydrating and ring-closing only a portion of the amic acid structure, resulting in the coexistence of the amic acid structure and the imide ring structure. The imidization rate of polyimide (P) is preferably 20% or more, more preferably 30% to 95%. The imidization rate is expressed as a percentage representing the proportion of the number of imide ring structures relative to the total number of amic acid structures and imide ring structures in the polyimide. Here, a portion of the imide ring may be an isoimide ring.

[0107] The dehydration and ring-closure of polyamic acid (P) is preferably carried out by dissolving polyamic acid (P) in an organic solvent, adding a dehydrating agent and a dehydration and ring-closure catalyst to the solution, and heating as needed. In this method, anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used as dehydrating agents. The amount of dehydrating agent used is preferably 0.01 mol to 20 mol relative to 1 mol of the amic acid structure of polyamic acid (P). Tertiary amines such as pyridine, trimethylpyridine, dimethylpyridine, and triethylamine can be used as dehydration and ring-closure catalysts. The amount of dehydration and ring-closure catalyst used is preferably 0.01 mol to 10 mol relative to 1 mol of the dehydrating agent used. Examples of organic solvents used in the synthesis of polyamic acid (P) can be cited as examples of organic solvents used in the dehydration and ring-closure reaction. The reaction temperature of the dehydration and ring-closure reaction is preferably 0°C to 180°C. The reaction time is preferably 1.0 h to 120 h. Furthermore, the reaction solution containing the polyimide (P) obtained through the reaction can be used directly for the preparation of a liquid crystal alignment agent, or it can be used for the preparation of a liquid crystal alignment agent after the polyimide (P) has been separated. Alternatively, polyimide (P) can also be obtained by imidization of polyamic acid ester (P).

[0108] Regarding the solution viscosity of polyamic acid, polyamic acid ester, and polyimide contained in the liquid crystal alignment agent, when preparing a 10% by mass solution, a solution viscosity of 10 mPa·s to 800 mPa·s is preferred, and a solution viscosity of 15 mPa·s to 500 mPa·s is more preferred. Furthermore, the solution viscosity (mPa·s) is a value obtained by measuring a 10% by mass polymer solution prepared using a type E rotational viscometer at 25°C with a good solvent for the polymer (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0109] The weight-average molecular weight (Mw) of polyamic acid, polyamic acid ester, and polyimide converted from polystyrene by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, more preferably 5,000 to 100,000. The molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the number-average molecular weight (Mn) of polystyrene determined by GPC, is preferably 15 or less, more preferably 10 or less.

[0110] (Polyorganosiloxane)

[0111] The method of manufacturing a polyorganosiloxane (hereinafter also referred to as "polysiloxane (P)") as a polymer (P) is not particularly limited as long as it has a partial structure represented by the formula (1). Polysiloxane (P) can be obtained, for example, by hydrolysis / condensation reaction of a hydrolytic silane compound. Specifically, the methods described in [1] and [2] below can be cited.

[0112] [1] A method for synthesizing an epoxy-containing polyorganosiloxane by hydrolyzing and condensing a silane compound (ms-1) having an epoxy group or a mixture of silane compound (ms-1) and other silane compounds, and then reacting the obtained epoxy-containing polyorganosiloxane with a carboxylic acid having a partial structure represented by the formula (1) (hereinafter also referred to as "specific carboxylic acid").

[0113] [2] A method for hydrolyzing and condensing a hydrolytic silane compound (ms-2) having a partial structure represented by formula (1) or a mixture of silane compound (ms-2) and other silane compounds.

[0114] Of these, method [1] is simple and can improve the incorporation rate of the partial structure represented by formula (1) in polysiloxane (P), and is preferred in this respect.

[0115] Specific examples of silane compounds (ms-1) include: 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-(3,4-epoxycyclohexyl)propyltrimethoxysilane, etc. As silane compounds (ms-1), one of these or a mixture of two or more can be used.

[0116] There are no particular restrictions on other silane compounds used in the synthesis of epoxy-containing polyorganosiloxanes, as long as they exhibit hydrolytic properties. Specific examples include, for instance, alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane.

[0117] 3-Mercaptopropyltrimethoxysilane, 3-Mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, 3-ureapropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(3-cyclohexylamino)propyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, and other alkoxysilanes containing nitrogen / sulfur atoms; 3-(meth)acryloyloxypropyltrimethoxysilane, Alkoxysilanes containing unsaturated hydrocarbons, such as 3-(meth)acryloyloxypropyltriethoxysilane, 6-(meth)acryloyloxyhexyltrimethoxysilane, 3-(meth)acryloyloxypropylmethyldimethoxysilane, 3-(meth)acryloyloxypropylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, and p-styryltrimethoxysilane, are also included. Other examples include trimethoxysilylpropylsuccinic anhydride. As other silane compounds, one or more can be used alone or in combination. Furthermore, in this specification, "(meth)acryloyloxy" includes both "acryloyloxy" and "methacryloyloxy".

[0118] The hydrolysis / condensation reaction of silane compounds can be carried out by reacting one or more of the silane compounds described above with water, preferably in the presence of a suitable catalyst and an organic solvent. During the reaction, the proportion of water used is preferably 1 to 30 moles relative to 1 mole of the total silane compound. Examples of catalysts used include acids, alkali metal compounds, organic bases, titanium compounds, zirconium compounds, etc. The amount of catalyst used varies depending on the type of catalyst, reaction conditions such as temperature, etc., and should be appropriately set; for example, it is preferably 0.01 to 3 moles relative to the total silane compound. Examples of organic solvents used include hydrocarbons, ketones, esters, ethers, alcohols, etc. Among these, water-insoluble or poorly soluble organic solvents are preferred. The proportion of organic solvent used is preferably 10 to 10,000 parts by mass relative to 100 parts by mass of the total silane compound used in the reaction.

[0119] The hydrolysis / condensation reaction is preferably carried out by heating, for example, in an oil bath. In this case, the heating temperature is preferably set to below 130°C, and the heating time is preferably set to 0.5 to 12 hours. After the reaction is complete, the organic solvent layer separated from the reaction solution is dried with a desiccant as needed to remove the solvent, thereby obtaining the target polyorganosiloxane. Furthermore, the synthesis method of the polyorganosiloxane is not limited to the hydrolysis / condensation reaction described above; for example, it can also be carried out by reacting a hydrolyzable silane compound in the presence of oxalic acid and an alcohol.

[0120] In the method described in [1], the epoxy-containing polyorganosiloxane obtained by the reaction is then reacted with a specific carboxylic acid. Thus, the epoxy groups of the epoxy-containing polyorganosiloxane react with the carboxyl groups of the specific carboxylic acid to obtain a polysiloxane (P) having a partial structure represented by formula (1) in its side chain.

[0121] Specific examples of a particular carboxylic acid include compounds represented by formulas (3-1) to (3-4) below.

[0122] [Chemistry 16]

[0123]

[0124] In one molecule of polysiloxane (P), the proportion of the partial structure represented by formula (1) relative to the silicon atoms present in polysiloxane (P) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more. Furthermore, in one molecule of polysiloxane (P), the proportion of the partial structure represented by formula (1) relative to the silicon atoms present in polysiloxane (P) is preferably 70 mol% or less, more preferably 60 mol% or less, and even more preferably 50 mol% or less.

[0125] Furthermore, in the synthesis of polysiloxanes (P), the carboxylic acid used in the reaction with the epoxy-containing polyorganosiloxane may be a specific carboxylic acid, but other carboxylic acids besides the specific carboxylic acid may also be used. Any carboxylic acid that does not have the partial structure represented by formula (1) may be used; various carboxylic acids can be employed. Examples of other carboxylic acids include, for instance, carboxylic acids having vertically oriented groups (mesocrystalline structures, etc.).

[0126] The reaction of epoxy-containing polyorganosiloxanes with carboxylic acids is preferably carried out in the presence of a catalyst and an organic solvent. As the catalyst used, for example, existing compounds that promote the reaction of organic bases and epoxy compounds as so-called curing accelerators (e.g., tertiary organic amines, quaternary organic amines, quaternary ammonium salts, etc.) can be used. The amount of catalyst used is preferably 100 parts by mass or less, more preferably 0.1 to 20 parts by mass, relative to 100 parts by mass of the epoxy-containing polyorganosiloxane.

[0127] Examples of organic solvents used in the reaction include hydrocarbons, ethers, esters, ketones, amides, and alcohols. The organic solvent is preferably used at a concentration of 0.1% by mass or more (the ratio of the total mass of components other than the solvent in the reaction solution to the total mass of the solution), more preferably at a concentration of 5% to 50% by mass. In the reaction, the reaction temperature is preferably 0°C to 200°C, more preferably 50°C to 150°C. The reaction time is preferably 0.1 hours to 50 hours, more preferably 0.5 hours to 20 hours. After the reaction is complete, the organic solvent layer separated from the reaction solution is preferably washed with water. After washing with water, the organic solvent layer is dried with a suitable desiccant if necessary, and the solvent is removed, thereby obtaining the polysiloxane (P) as the target material.

[0128] The polysiloxane (P) preferably has a solution viscosity of 1 mPa·s to 500 mPa·s when prepared as a 10% by mass solution, more preferably a solution viscosity of 3 mPa·s to 200 mPa·s. Regarding the polysiloxane (P), the weight-average molecular weight (Mw) of the polystyrene, as determined by GPC, is preferably 1,000 to 200,000, more preferably 2,000 to 50,000, and even more preferably 3,000 to 20,000.

[0129] (Addition polymer)

[0130] The method of manufacturing an addition polymer (hereinafter also referred to as "addition polymer (P)") as long as it has the partial structure represented by the formula (1) is not particularly limited. The addition polymer (P) is preferably a polymer having structural units derived from monomers that have polymerizable carbon-carbon unsaturated bonds (hereinafter also referred to as "unsaturated monomers"). The addition polymer (P) can be obtained, for example, by polymerizing an unsaturated monomer (ma-1) having the partial structure represented by the formula (1), or a mixture of an unsaturated monomer (ma-1) and other unsaturated monomers.

[0131] As an unsaturated monomer, any monomer having polymerizable carbon-carbon unsaturated bonds can be used. Examples of such monomers include compounds having (meth)acryloyl, vinyl, vinylphenyl, and maleimide groups. Regarding the formation of liquid crystal alignment films with excellent liquid crystal orientation properties, at least one unsaturated polymer (P) preferably uses the group consisting of poly(meth)acrylates, maleimide polymers, and styrene-maleimide copolymers.

[0132] The unsaturated monomer (ma-1) is not particularly limited as long as it has the partial structure represented by formula (1). Specific examples of unsaturated monomers (ma-1) include compounds represented by formulas (4-1) to (4-10) respectively.

[0133] [Chemistry 17]

[0134]

[0135] Other specific examples of unsaturated monomers include: unsaturated carboxylic acids such as (meth)acrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, and vinylbenzoic acid; unsaturated carboxylic acid esters such as alkyl (meth)acrylates (e.g., methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, cycloalkyl (meth)acrylates, benzyl (meth)acrylate, trimethoxysilylpropyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, glycidyl (meth)acrylate, 3,4-epoxycyclohexyl methyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, and 4-hydroxybutyl glycidyl (meth)acrylate; and unsaturated polycarboxylic anhydrides such as maleic anhydride.

[0136] Aromatic vinyl compounds such as styrene, methylstyrene, divinylbenzene and 4-(glycidoxymethyl)styrene; conjugated diene compounds such as 1,3-butadiene and 2-methyl-1,3-butadiene;

[0137] Compounds such as N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, 4-(2,5-dioxo-3-pyrrololin-1-yl)benzoic acid, N-(4-glycidyloxyphenyl)maleimide, N-glycidylmaleimide, 3-maleimidebenzoic acid, 3-maleimidepropionic acid, 3-(2,5-dioxo-3-pyrrololin-1-yl)benzoic acid, and methyl 4-(2,5-dioxo-3-pyrrololin-1-yl)benzoate are maleimide compounds. In the synthesis of addition polymers (P), they can be used as other unsaturated monomers, either alone or in combination of two or more.

[0138] In one molecule of the addition polymer (P), the proportion of the partial structure represented by formula (1) is preferably 2 mol% or more, more preferably 5 mol% or more, and even more preferably 10 mol% or more, relative to all the structural units of the addition polymer (P). Furthermore, in one molecule of the addition polymer (P), the proportion of the partial structure represented by formula (1) is preferably 60 mol% or less, more preferably 50 mol% or less, and even more preferably 40 mol% or less, relative to all the structural units of the addition polymer (P).

[0139] Addition polymers (P) can be obtained, for example, by polymerizing monomers in the presence of a polymerization initiator. Preferred polymerization initiators include, for example, azo compounds such as 2,2'-azobis(isobutyronitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile). The proportion of polymerization initiator used is preferably set to 0.01 to 30 parts by mass relative to 100 parts by mass of all monomers used in the reaction.

[0140] The polymerization reaction is preferably carried out in an organic solvent. Examples of organic solvents used in the reaction include alcohols, ethers, ketones, amides, esters, and hydrocarbon compounds, with diethylene glycol ethyl methyl ether and propylene glycol monomethyl ether acetate being preferred. The reaction temperature is preferably set to 30°C to 120°C, and the reaction time is preferably set to 1 hour to 36 hours. The amount (a) of organic solvent used is preferably set to be 0.1% to 60% by mass relative to the total amount (b) of monomers used in the reaction and the total amount (a+b) of the reaction solution.

[0141] For the addition polymer (P), the weight-average molecular weight (Mw) of polystyrene as determined by GPC is preferably 250 to 500,000, more preferably 500 to 100,000. Furthermore, the molecular weight distribution (Mw / Mn), expressed as the ratio of Mw to the number-average molecular weight (Mn) of polystyrene as determined by GPC, is preferably 8 or less, more preferably 6 or less.

[0142] Furthermore, the method for manufacturing addition polymers (P) is not limited to those described above. For example, it can also be obtained by polymerizing a monomer containing an unsaturated monomer (m-1) having an epoxy group in the presence of a polymerization initiator, and then reacting the polymer of the obtained monomer with a specific carboxylic acid.

[0143] The polymer (P) preferably comprises a structural unit derived from a monomer having at least one partial structure selected from the group consisting of nitrogen-containing heterocycles, amino groups, protected amino groups, amide groups, protected amide groups, urea groups, and protected urea groups (hereinafter also referred to as "nitrogen-containing monomers"). The nitrogen-containing monomer is a base capable of incorporating at least one partial structure selected from the group consisting of nitrogen-containing heterocycles, amino groups, protected amino groups, amide groups, protected amide groups, urea groups, and protected urea groups into the polymer (P). When the polymer (P) has a structural unit derived from a nitrogen-containing monomer, in addition to the improved effect resulting from the incorporation of the partial structure represented by formula (1), a further improvement in long-term thermal reliability can be obtained, which is preferred in this respect.

[0144] Examples of nitrogen-containing heterocycles include: pyrrole, imidazole, pyrazole, triazole, pyridine, pyrimidine, pyridazine, pyrazine, indole, benzimidazole, purine, quinoline, isoquinoline, naphthidine, quinoxaline, phthalazine, triazine, carbazole, acridine, piperidine, piperazine, pyrrolidine, hexamethyleneimine, etc. Preferably, the nitrogen-containing heterocycle of the nitrogen-containing monomer is selected from at least one group consisting of pyridine, pyrimidine, pyrazine, piperidine, piperazine, quinoline, benzimidazole, carbazole, and acridine.

[0145] The amino group, the protected amino group, the amide group, the protected amide group, the urea group, and the protected urea group are preferably structures represented by the following formula (N-1).

[0146] [Chemistry 18]

[0147]

[0148] (In formula (N-1), R) 20 It consists of a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent thermally decomposable group. (* indicates a bond.)

[0149] In the above equation (N-1), R is... 20 The monovalent hydrocarbon group represented can be, for example, alkyl groups such as methyl, ethyl, and propyl; cycloalkyl groups such as cyclohexyl; and aryl groups such as phenyl and methylphenyl. As R... 20 The monovalent thermally detachable radical represented can be applied using R. 3 Specific examples and preferred examples are explained for monovalent thermally detachable radicals. R 20 Preferably, it is a hydrogen atom, methyl, or tert-butoxycarbonyl group. When the nitrogen-containing monomer has an amino group, the amino group is preferably a group different from the group participating in the polymerization, more preferably a secondary or tertiary amino group.

[0150] Regarding the improvement in long-term thermal reliability, the nitrogen-containing monomer is preferably a monomer having at least one selected from the group consisting of a nitrogen-containing heterocycle, a protected amino group, and a protected amide group, and is particularly preferably a monomer having a nitrogen-containing heterocycle. Preferably, a monomer capable of introducing at least one selected from the group consisting of a nitrogen-containing heterocycle, a protected amino group, and a protected amide group into the side chain of the polymer is used, and more preferably, a monomer capable of introducing a nitrogen-containing heterocycle into the side chain of the polymer is used. Furthermore, the nitrogen-containing monomer is preferably a compound that does not have the partial structure represented by formula (1). That is, preferably, the nitrogen-containing structure and the structural unit having the partial structure represented by formula (1) are separately introduced into the polymer (P).

[0151] When the polymer (P) comprises structural units derived from a nitrogen-containing monomer, the polymer (P) is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide. In this case, the nitrogen-containing monomer is preferably a diamine, more preferably a diamine having at least one partial structure selected from the group consisting of a nitrogen-containing heterocycle, secondary amino group, tertiary amino group, protected amino group, amide group, protected amide group, urea group, and protected urea group.

[0152] Specific examples of nitrogen-containing monomers that are diamines include: 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4-bis-(4-aminophenyl)-piperazine, 3,6-diaminoacridine, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N,N'-bis(4-aminophenyl)-benzidine, N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, and compounds represented by formulas (N-1-1) to (N-1-17) respectively.

[0153] [Chemistry 19]

[0154]

[0155] [Chemistry 20]

[0156]

[0157] In the polymer (P), from the viewpoint of fully obtaining the improvement effect on long-term thermal reliability, the proportion of structural units derived from nitrogen-containing monomers relative to the total amount of structural units in the polymer (P) is preferably 1 mol% or more, more preferably 2 mol% or more, and even more preferably 5 mol% or more. Furthermore, the proportion of structural units derived from nitrogen-containing monomers relative to the total amount of structural units in the polymer (P) is preferably 40 mol% or less, more preferably 35 mol% or less. The nitrogen-containing monomer can be used alone or in combination of two or more.

[0158] When the polymer (P) contains structural units derived from nitrogen-containing monomers, the polymer (P) preferably also contains structural units derived from monomers having carboxyl groups or protected carboxyl groups (hereinafter also referred to as "carboxyl-containing monomers"). By further incorporating structural units derived from carboxyl-containing monomers into the polymer (P), the electrical properties of the liquid crystal alignment film can be improved, and long-term thermal reliability and resistance to high temperature and humidity can be improved, which is preferred in this respect.

[0159] Specific examples of diamines containing a carboxyl group include: 3,5-diaminobenzoic acid, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, and compounds formed by replacing the hydrogen atoms of the carboxyl group of these diamines with thermally detachable groups (e.g., tertiary hydrocarbon groups, groups with acetal structures, etc.).

[0160] When the polymer (P) contains structural units derived from carboxyl-containing monomers, from the viewpoint of fully obtaining improved long-term thermal reliability and resistance to high temperature and humidity, the proportion of structural units derived from carboxyl-containing monomers relative to the total number of structural units in the polymer (P) is preferably 1 mol% or more, more preferably 2 mol% or more, and even more preferably 5 mol% or more. Furthermore, the proportion of structural units derived from carboxyl-containing monomers relative to the total number of structural units in the polymer (P) is preferably 40 mol% or less, more preferably 35 mol% or less. The carboxyl-containing monomer can be used alone or in combination of two or more.

[0161] Additionally, the polymer (P) may contain structural units derived from a monomer that has at least one of the following groups (hereinafter also referred to as "vertically oriented groups") having a side chain of an alkyl group selected from 4 to 30 carbon atoms, a halogenated alkyl group with 4 to 30 carbon atoms, an alkoxy group with 4 to 30 carbon atoms, a halogenated alkoxy group with 4 to 30 carbon atoms, a polycyclic structure having two or more rings directly or through a divalent linker, and a group having a steroid backbone, and does not have a monomer (hereinafter also referred to as "monomer containing oriented groups") representing a partial structure of the formula (1).

[0162] As a specific example of a vertically oriented base, the base represented by the following equation (5) can be listed.

[0163] *-L 1 -R 11 -R 12 -R 13 -R 14 …(5)

[0164] (In equation (5), L) 1 For single bonds, -O-, -CO-, -COO-* 1 -OCO-* 1 -NR 15 -、-NR 15 -CO-* 1 -CO-NR 15 -* 1 Alkyl groups with 1 to 6 carbon atoms, -OR 16 -* 1 , or -R 16 -O-* 1 (where R) 15 R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. 16 It is an alkyldiyl group having 1 to 3 carbon atoms. 1 "Indicates to R" 11 The bond structure. ). R 11 and R 13 Each is independently a single bond, a phenylene group, or a cycloalkylene group, R 12 Single bond, phenylene, cycloalkylene, -R 17 -B 1 -* 2 、or -B 1 -R 17 -* 2 (where R) 17 It is a phenylene or cycloalkylene group, B 1 -COO-* 3 -OCO-* 3 Or alkyldiyl groups having 1 to 3 carbon atoms. 2 "Indicates to R"13 The key, "* 3 "Indicates to R" 17 The bond structure. ). R 14 It consists of a hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 30 carbon atoms, a fluoroalkyl group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, a fluoroalkoxy group having 1 to 30 carbon atoms, or a hydrocarbon group having 17 to 51 carbon atoms with a steroid skeleton. Among these, in R... 11 R 12 and R 13 When all keys are single keys, R 14 It can be an alkyl group with 4 to 30 carbon atoms, a fluoroalkyl group with 4 to 30 carbon atoms, an alkoxy group with 4 to 30 carbon atoms, a fluoroalkoxy group with 4 to 30 carbon atoms, or a hydrocarbon group with 17 to 51 carbon atoms having a steroid skeleton. * indicates a bond.

[0165] In equation (5), L 1 B 1 alkyl diols, and R 14 The alkyl, fluoroalkyl, alkoxy, and fluoroalkoxy groups are preferably linear. As R 14 The group having a steroid skeleton, for example, includes: cholesteryl group, cholesteryl group, lanostane group, etc. R is preferred. 11 R 12 and R 13 At least two of them have phenylene or cycloalkylene groups.

[0166] As specific examples of the partial structure represented by formula (5), examples include the partial structures represented by formulas (5-1) to (5-12) below, such as cholesteryloxy, cholesteryloxycarbonyl, cholesteryloxy, lanostaneyloxy, etc. The vertically oriented group is not limited to these specific examples.

[0167] [Chemistry 21]

[0168]

[0169] In polymer (P), from the viewpoint of obtaining good pretilt angle characteristics, the proportion of structural units derived from monomers containing orientation groups relative to the total number of structural units in polymer (P) is preferably 1 mol% or more, more preferably 2 mol% or more, and even more preferably 5 mol% or more. Furthermore, the proportion of structural units derived from monomers containing orientation groups relative to the total number of structural units in polymer (P) is preferably 30 mol% or less, more preferably 20 mol% or less. The monomers containing orientation groups may be used alone or in combination of two or more.

[0170] Furthermore, in the polymer (P), structural units derived from monomers containing orientation groups are introduced separately from structural units having the partial structure represented by formula (1). In this case, the amount of structural units derived from monomers containing orientation groups can be adjusted independently of the amount of partial structure represented by formula (1). In addition, when vertical orientation groups are introduced into the polymer, a liquid crystal alignment film with high film density can be formed, thereby obtaining a liquid crystal alignment film with good narrow line adhesion, long-term thermal reliability, and high temperature and humidity resistance, which is preferred in this respect.

[0171] The proportion of polymer (P) in the liquid crystal alignment agent is preferably 2% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more, relative to the total amount of polymer components contained in the liquid crystal alignment agent. Furthermore, the polymer (P) used in the preparation of the liquid crystal alignment agent may be only one type, or two or more types may be combined. Based on the liquid crystal alignment agent containing polymer (P), a liquid crystal alignment film exhibiting good pretilt angle characteristics, high reliability under harsh conditions, and excellent narrow-line adhesion can be obtained.

[0172] <Other Ingredients>

[0173] The liquid crystal alignment agent disclosed herein contains polymer (P) as described above, but may also contain other components besides polymer (P) as needed.

[0174] (Aggregate (Q))

[0175] For the purpose of further improving the liquid crystal alignment or electrical properties, the liquid crystal alignment agent disclosed herein may also contain a polymer (hereinafter also referred to as "polymer (Q)") that does not have the partial structure represented by the formula (1).

[0176] Examples of polymers (Q) include polyamic acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane, and addition polymers. From the viewpoint of improving electrical properties, affinity with liquid crystals, mechanical strength, and affinity with the polymer (P), the polymer (Q) is preferably at least one selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, polyorganosiloxane, and addition polymers, and more preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, and polyorganosiloxane.

[0177] From the viewpoint that the improved effect of the formulation of polymer (P) and polymer (Q) can be uniformly exhibited when polymer (Q) is contained in the liquid crystal alignment agent, the content ratio of polymer (Q) is preferably set to 1 part by mass or less, more preferably 2 parts by mass or less, and even more preferably 5 parts by mass or less, relative to the total mass of polymer (P) and polymer (Q) contained in the liquid crystal alignment agent of 100 parts by mass.

[0178] (Cross-linking agent)

[0179] The liquid crystal alignment agent disclosed herein may further contain a crosslinking agent. By further containing a crosslinking agent, the film density of the liquid crystal alignment film can be increased, which can further improve the effect on narrow line adhesion, and is preferred in this respect.

[0180] As a crosslinking agent, examples include compounds having functional groups (hereinafter also referred to as "crosslinking groups") capable of reacting with functional groups (e.g., amino, carboxyl, epoxy, polymeric unsaturated bond groups, etc.) possessed by polymer (P) or polymer (Q). Specifically, examples of crosslinking groups include: cyclic ether groups, carboxyl groups, cyclic carbonate groups, alcoholic hydroxyl groups (hydroxymethyl, etc.), β-hydroxyamide groups, amino groups, protected amino groups, protected isocyanate groups, trialkoxysilyl groups, polymeric unsaturated bond groups, maleimide groups, etc. The number of crosslinking groups possessed by the crosslinking agent is preferably two or more, more preferably three or more, and even more preferably three to six.

[0181] When formulating a crosslinking agent, the content of the crosslinking agent in the liquid crystal alignment agent is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, relative to 100 parts by mass of the total polymer component in the liquid crystal alignment agent. Furthermore, from the viewpoint of suppressing performance degradation due to excessive addition, the content of the crosslinking agent is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, relative to 100 parts by mass of the total polymer component in the liquid crystal alignment agent. In addition, one type of crosslinking agent or a combination of two or more types can be used as the crosslinking agent.

[0182] (solvent)

[0183] Liquid crystal alignment agents are typically prepared in the form of a liquid composition, preferably a polymer (P) and other components as needed, dispersed or dissolved in a suitable solvent.

[0184] Examples of organic solvents used include: N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,2-dimethyl-2-imidazolium ketone, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone (diacetone alcohol), ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, etc. Ethyl alcohol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, ethylene carbonate, propylene carbonate, etc. These can be used alone or in combination of two or more.

[0185] Other components, besides those mentioned above, may include, for example, functional silane compounds, polyfunctional (meth)acrylates, antioxidants, metal chelate compounds, curing accelerators, surfactants, fillers, dispersants, photosensitizers, etc. The proportions of these other components may be appropriately selected based on the specific compounds, without compromising the effectiveness of this disclosure.

[0186] The concentration of solid components in the liquid crystal alignment agent (the proportion of the total mass of components other than the solvent in the total mass of the liquid crystal alignment agent) can be appropriately selected considering factors such as viscosity and volatility, and is preferably in the range of 1% to 10% by mass. That is, the liquid crystal alignment agent is coated onto the substrate surface as described later, preferably by heating, thereby forming a coating that serves as a liquid crystal alignment film or a coating that forms a liquid crystal alignment film. At this point, if the solid component concentration is 1% by mass or more, the film thickness of the coating can be sufficiently ensured, and a good liquid crystal alignment film can be easily obtained, which is preferable from this viewpoint. Furthermore, if the solid component concentration is 10% by mass or less, the film thickness of the coating will not become excessive, a good liquid crystal alignment film can be obtained, and the viscosity of the liquid crystal alignment agent can be appropriately ensured, resulting in good coatability.

[0187] Based on the above description of this disclosure, the following liquid crystal alignment agent is provided.

[0188] <Means 1> A liquid crystal alignment agent containing a polymer (P) having a partial structure represented by the formula (1).

[0189] <Meaning 2> The liquid crystal alignment agent according to <Meaning 1>, wherein the polymer (P) is at least one selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane and addition polymers.

[0190] <Method 3> The liquid crystal alignment agent according to <Method 1> or <Method 2>, wherein the polymer (P) comprises structural units derived from a diamine having a partial structure represented by the formula (1).

[0191] <Means 4> The liquid crystal alignment agent according to <Means 3>, wherein the diamine is at least one selected from the group consisting of the compound represented by formula (2-1) and the compound represented by formula (2-2).

[0192] <Method 5> The liquid crystal alignment agent according to any one of <Method 1> to <Method 4> further comprises a polymer that does not have the partial structure represented by the formula (1).

[0193] <Meaning 6> The liquid crystal alignment agent according to any one of <Meaning 1> to <Meaning 5>, wherein the polymer (P) comprises a structural unit derived from a monomer having at least one partial structure selected from the group consisting of nitrogen-containing heterocycles, amino groups, protected amino groups, amide groups, protected amide groups, urea groups and protected urea groups.

[0194] <Method 7> A liquid crystal alignment agent according to any one of <Method 1> to <Method 6>, wherein the polymer (P) comprises a structural unit derived from a monomer having at least one of the following groups in which the side chain is selected from an alkyl group having 4 to 30 carbon atoms, a halogenated alkyl group having 4 to 30 carbon atoms, an alkoxy group having 4 to 30 carbon atoms, a halogenated alkoxy group having 4 to 30 carbon atoms, a polycyclic structure having two or more rings directly or through a divalent linker, and a group having a steroid backbone, and does not have a partial structure represented by the formula (1).

[0195] <<Liquid Crystal Alignment Films and Liquid Crystal Elements>>

[0196] The liquid crystal alignment film disclosed herein can be formed from a liquid crystal alignment agent prepared as described above. Furthermore, the liquid crystal element of this disclosure includes a liquid crystal alignment film formed using the liquid crystal alignment agent described above. The operating mode of the liquid crystal in the liquid crystal element is not particularly limited, and can be applied to various modes such as twisted nematic (TN), super twisted nematic (STN), vertical alignment (VA) (including vertical alignment-multi-domain vertical alignment (VA-MVA), vertical alignment-patterned vertical alignment (VA-PVA), etc.), in-plane switching (IPS), fringe field switching (FFS), optically compensated bending (OCB), and polymer-sustained alignment (PSA). Liquid crystal elements can be manufactured, for example, by a method including the following steps 1 to 3. In step 1, the substrate used varies depending on the desired operating mode. Steps 2 and 3 are common to all operating modes.

[0197] (Step 1: Coating Formation)

[0198] First, a liquid crystal alignment agent is coated onto a substrate, preferably by heating the coated surface, thereby forming a coating film on the substrate. Examples of substrates that can be used include: float glass, soda glass, etc.; and transparent substrates containing plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly(alicyclic olefins). As a transparent conductive film disposed on one side of the substrate, a NESA film (a registered trademark of PPG Industries, Inc.) containing tin oxide (SnO2) or an indium tin oxide (ITO) film containing indium oxide-tin oxide (In2O3-SnO2) can be used. When manufacturing TN, STN, or VA type liquid crystal elements, two substrates with patterned transparent conductive films are used. On the other hand, when manufacturing IPS or FFS type liquid crystal elements, a substrate with electrodes containing a patterned comb-shaped transparent conductive film or metal film and an opposing substrate without electrodes are used. As a metal film, for example, a film containing metals such as chromium can be used. The coating of the liquid crystal alignment agent on the substrate is preferably performed on the electrode forming surface using offset printing, spin coating, roller coating or inkjet printing.

[0199] After applying the liquid crystal alignment agent, preheating (pre-baking) is preferably performed to prevent the liquid crystal alignment agent from dripping. The pre-baking temperature is preferably 30°C to 150°C, more preferably 40°C to 120°C. The pre-baking time is preferably 0.25 minutes to 10 minutes.

[0200] Then, a calcination (post-baking) process is performed to further remove the solvent and, if necessary, to thermally imide the amyl acid structure present in the polymer. From the viewpoint of suppressing degradation such as fading caused by high temperatures during the formation of the liquid crystal alignment film on the color filter, and from the viewpoint of reducing environmental impact, the calcination temperature (post-baking temperature) at this time is preferably 250°C or lower, more preferably 230°C or lower, and even more preferably 180°C or lower. Furthermore, from the viewpoint of suppressing the decrease in liquid crystal alignment or reliability due to the influence of residual solvent components in the film, the post-baking temperature is preferably 80°C or higher, more preferably 120°C or higher. The post-baking time is preferably 5 minutes to 150 minutes. The film thickness thus formed is preferably 0.001 μm to 1 μm. After the liquid crystal alignment agent is coated onto the substrate, the organic solvent is removed, thereby forming a liquid crystal alignment film, or a coating that becomes a liquid crystal alignment film.

[0201] (Process 2: Orientation Treatment)

[0202] In manufacturing TN, STN, IPS, or FFS type liquid crystal elements, a process (alignment treatment) is performed to impart liquid crystal alignment capability to the coating film formed in step 1. This imparts the alignment capability of the liquid crystal molecules to the coating film, creating a liquid crystal alignment film. Preferably, the alignment treatment involves rubbing the surface of the coating film formed on the substrate with cotton or the like, or photoalignment treatment by irradiating the coating film with light to impart liquid crystal alignment capability. In manufacturing vertically aligned liquid crystal elements, the coating film formed in step 1 can be used directly as a liquid crystal alignment film; however, to further improve the liquid crystal alignment capability, an alignment treatment can also be performed on the coating film. The liquid crystal alignment film preferred for vertically aligned liquid crystal display elements can also preferably be used for PSA type liquid crystal display elements.

[0203] Light irradiation in photoalignment processing can be performed by methods such as: irradiating a coating after a post-baking process; irradiating a coating after a pre-baking process and before a post-baking process; or irradiating the coating during heating in at least one of the pre-baking and post-baking processes. In photoalignment processing, the radiation used to irradiate the coating can be, for example, ultraviolet light or visible light with wavelengths from 150 nm to 800 nm. Ultraviolet light with wavelengths from 200 nm to 400 nm is preferred. When the radiation is polarized, it can be linearly polarized or partially polarized. Furthermore, when using linearly polarized or partially polarized radiation, irradiation can be performed from a direction perpendicular to the substrate surface, from an inclined direction, or a combination of these. When irradiating unpolarized radiation, the irradiation direction is set to an inclined direction.

[0204] The light source used 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. The preferred radiation dose is 400 J / m². 2 ~20,000 J / m 2 More preferably 1,000 J / m 2 ~5,000 J / m 2 To improve reactivity, the coating film can be heated while being irradiated with light. Furthermore, the process may include a step of contacting the light-treated organic film with water, a water-soluble organic solvent, or a mixture of water and a water-soluble organic solvent.

[0205] (Step 3: Construction of liquid crystal cells)

[0206] Two substrates with liquid crystal alignment films formed as described above are prepared, and liquid crystal is disposed between the two substrates facing each other, thereby manufacturing a liquid crystal cell. Examples of methods for manufacturing a liquid crystal cell include: [1] arranging two substrates facing each other with liquid crystal alignment films facing each other and a gap (spacer) between them, bonding the peripheries of the two substrates together with a sealant, injecting liquid crystal to fill the cell gap defined by the substrate surface and the sealant, and sealing the injection hole; [2] applying a sealant to a predetermined area on one of the substrates with the liquid crystal alignment film, then dropping liquid crystal at predetermined locations on the surface of the liquid crystal alignment film, bonding the other substrate with the liquid crystal alignment films facing each other, and allowing the liquid crystal to diffuse across the entire surface of the substrate (one-drop filling (ODF) method), etc. Preferably, the manufactured liquid crystal cell is further subjected to a process that involves heating it to a temperature at which the liquid crystal used achieves an isotropic phase, and then slowly cooling it to room temperature, thereby removing the flow alignment during liquid crystal filling.

[0207] As a sealant, for example, a hardener and epoxy resin containing alumina balls as spacers can be used. As spacers, photoresist spacers, bead spacers, etc., can be used.

[0208] Examples of liquid crystals used include nematic liquid crystals and smectic liquid crystals, with nematic liquid crystals being preferred. Examples of nematic liquid crystals include Schiff base-based liquid crystals, azo-based liquid crystals, biphenyl-based liquid crystals, phenylcyclohexane-based liquid crystals, ester-based liquid crystals, terphenyl-based liquid crystals, biphenylcyclohexane-based liquid crystals, pyrimidine-based liquid crystals, dioxane-based liquid crystals, dicyclooctane-based liquid crystals, and cubane-based liquid crystals. Furthermore, cholesteric liquid crystals, chiral reagents, and ferroelectric liquid crystals can be added to these liquid crystals for further processing.

[0209] As one aspect of the manufacturing method of the liquid crystal element disclosed herein, a method including the following steps [A] to [C] can be listed.

[0210] [A] A process of forming a coating by coating the liquid crystal alignment agent of the present disclosure onto each conductive film of a pair of substrates having conductive films.

[0211] [B] A process of constructing a liquid crystal cell by arranging a pair of substrates with coatings facing each other with the coatings separated by a liquid crystal layer.

[0212] [C] A process of irradiating the liquid crystal cell with light while applying a voltage between the conductive films.

[0213] For example, in PSA mode, the following process is performed: a polymeric compound (such as a polyfunctional (meth)acrylate compound) is filled into the intercellular space along with liquid crystal, and after the liquid crystal cell is constructed, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of a pair of substrates. When manufacturing a PSA mode liquid crystal element, the proportion of the polymeric compound used is, for example, 0.01 to 3 parts by mass, preferably 0.1 to 1 part by mass, relative to a total of 100 parts by mass of liquid crystal.

[0214] Next, a polarizing plate is attached to the outer surface of the liquid crystal cell as needed. Examples of polarizing plates include those formed by sandwiching a polarizing film called an "H-film" with a cellulose acetate protective film, or those containing an H-film itself, wherein the "H-film" is formed by absorbing iodine while extending and aligning polyvinyl alcohol. Thus, a liquid crystal element is obtained.

[0215] The liquid crystal element disclosed herein can be effectively applied to a variety of uses. Specifically, it can be used in various display devices such as clocks, portable game consoles, word processors, laptop personal computers, car navigation systems, camcorders, personal digital assistants (PDAs), digital cameras, mobile phones, smartphones, various monitors, LCD TVs, information displays, or dimming films. Furthermore, the liquid crystal element formed using the liquid crystal alignment agent disclosed herein can also be used in optical films such as retardation films.

[0216] [Example]

[0217] The following is a detailed description using examples, but the content of this disclosure is not limited to the following examples.

[0218] In the following examples, the weight-average molecular weight (Mw), number-average molecular weight (Mn), and molecular weight distribution (Mw / Mn), the imidization rate of the polyimide, and the solution viscosity of the polymer solution were determined by the following methods.

[0219] <Weight-average molecular weight, number-average molecular weight, and molecular weight distribution>

[0220] Mw and Mn were determined by gel permeation chromatography (GPC) under the following conditions. Furthermore, the molecular weight distribution (Mw / Mn) was calculated from the obtained Mw and Mn.

[0221] Device: Showa Denko (stock)'s "GPC-101"

[0222] GPC tubing: Combining Shimadzu GLC's "GPC-KF-801", "GPC-KF-802", "GPC-KF-803" and "GPC-KF-804"

[0223] Mobile phase: Tetrahydrofuran (THF)

[0224] Column temperature: 40℃

[0225] Flow rate: 1.0 mL / min

[0226] Sample concentration: 1.0% by mass

[0227] Sample injection volume: 100 μL

[0228] Detector: Differential refractometer

[0229] Standard material: Monodisperse polystyrene

[0230] <Imidification rate of polyimide>

[0231] The imidized polymer was dried under reduced pressure at room temperature and then dissolved in deuterated dimethyl sulfoxide. Tetramethylsilane was used as a reference substance, and proton NMR spectra were measured at room temperature. 1 The imidization rate was determined by the formula (I) below, representing the H-Nuclear Magnetic Resonance (NMR).

[0232] Imidification rate (%) = (1-(A) 1 / (A 2 ×α)))×100…(I)

[0233] (In formula (I), A 1 It is the peak area of ​​protons originating from NH groups that appears near a chemical shift of 10 ppm, A 2 It is the peak area derived from other protons, and α is the ratio of the number of other protons to the number of 1 proton of the NH group in the polymer precursor (polyamic acid).

[0234] <Solution viscosity of polymer solutions>

[0235] The solution viscosity (mPa·s) of the polymer solution was measured using an E-type rotational viscometer at 25°C.

[0236] The compounds used in the examples below are shown below. In addition, for convenience, the "compound represented by formula (X)" will sometimes be simply referred to as "compound (X)".

[0237] (Tetracarboxylic acid dianhydride)

[0238] [Chemistry 22]

[0239]

[0240] (Specific diamine)

[0241] [Chemistry 23]

[0242]

[0243] (Other diamines)

[0244] [Chemistry 24]

[0245]

[0246] [Chemistry 25]

[0247]

[0248] [Chemistry 26]

[0249]

[0250] [Chemistry 27]

[0251]

[0252] (Unsaturated monomers)

[0253] [Chemistry 28]

[0254]

[0255] (additive)

[0256] [Chemistry 29]

[0257]

[0258] <Synthesis of Monomers>

[0259] [Synthetic Example 1-1: Synthesis of Compound (M-1)]

[0260] The following procedure was followed to synthesize compound (M-1).

[0261] [Chemistry 30]

[0262]

[0263] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 23.21 g of acetone were dissolved in 100 mL of acetonitrile and reacted at 45 °C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice using 100 mL of 1 equivalent hydrochloric acid and twice using 100 mL of water. The organic layer was concentrated using an evaporator, and then thermally recrystallized by adding hexane. The obtained solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 10.1 g of compound (M-1-1).

[0264] Subsequently, 50 mL of tetrahydrofuran was added to 4.00 g of compound (M-1-1) and 4.96 g of 3,5-dinitrobenzyl chloride, and the mixture was heated to 40 °C. A solution prepared by dissolving 1.00 g of sodium hydroxide in 35 mL of distilled water was added dropwise, and the mixture was allowed to react at room temperature for 12 hours after the addition was complete. After the reaction, the reaction solution was injected into 500 mL of distilled water, and the precipitated solid was filtered and washed with 2-propanol. Then, the mixture was vacuum dried and recrystallized to obtain 6.9 g of compound (M-1-2).

[0265] 5.0 g of compound (M-1-2), 0.86 g of 5% palladium on carbon, 30 mL of tetrahydrofuran, and 30 mL of ethanol were added, and the mixture was heated to 80 °C. 4.03 g of hydrazine monohydrate was then added dropwise, and the mixture was heated under reflux for 6 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated using 600 mL of distilled water. The obtained solid was filtered, washed with water, and then dried under vacuum to obtain 3.8 g of compound (M-1).

[0266] [Synthetic Example 1-2: Synthesis of Compound (M-2)]

[0267] The following procedure is followed to synthesize compound (M-2).

[0268] [Chemistry 31]

[0269]

[0270] The compound (M-2-1) was synthesized in 6.5 g by means of the method described in Bioorganic & Medicinal Chemistry Letters (Bioorg. Med. Chem. Lett.) 1999, 9, 2773-2778.

[0271] Subsequently, 5.0 g of compound (M-2-1) and 3.70 g of triethylamine were dissolved in 30 mL of N,N-dimethylformamide. A solution prepared by dissolving 5.95 g of 2,4-dinitrofluorobenzene in 20 mL of N,N-dimethylformamide was added dropwise, and the reaction was allowed to proceed at room temperature for 8 hours. After the reaction, the reaction solution was reprecipitated using 400 mL of distilled water. The obtained solid was filtered, washed with water and ethanol, and then dried under vacuum to obtain 9.1 g of compound (M-2-2).

[0272] 7.0 g of compound (M-2-2), 1.35 g of 5% palladium on carbon, 45 mL of tetrahydrofuran, and 45 mL of ethanol were added, and the mixture was heated to 80 °C. 6.37 g of hydrazine monohydrate was then added dropwise, and the mixture was heated under reflux for 6 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated using 900 mL of distilled water. The obtained solid was filtered, washed with water, and then dried under vacuum to obtain 5.8 g of compound (M-2).

[0273] [Synthetic Examples 1-3: Synthesis of Compound (M-3)]

[0274] The following procedure is followed to synthesize compound (M-3).

[0275] [Chemistry 32]

[0276]

[0277] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 28.44 g of butyraldehyde were dissolved in 100 mL of acetonitrile and reacted at 45 °C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice using 100 mL of 1 equivalent hydrochloric acid and twice using 100 mL of water. The organic layer was concentrated using an evaporator, and then thermally recrystallized by adding hexane. The obtained solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 10.8 g of compound (M-3-1).

[0278] Subsequently, 7.00 g of compound (M-3-1) and 6.87 g of triethylamine were dissolved in 120 mL of tetrahydrofuran, and the solution was cooled to 0°C in an ice bath. A solution containing 7.83 g of 3,5-dinitrobenzoyl chloride dissolved in 80 mL of tetrahydrofuran was then added dropwise. After the addition was complete, the mixture was allowed to react at room temperature for 12 hours. Following the reaction, the reaction solution was reprecipitated using 900 mL of distilled water. The obtained solid was filtered, washed with water and 2-propanol, and then dried under vacuum to obtain 11.1 g of compound (M-3-2).

[0279] 10.0 g of compound (M-3-2) and 1.59 g of 5% palladium on carbon were added to 50 mL of tetrahydrofuran and 50 mL of ethanol. After purging the reaction vessel with hydrogen, the reaction was carried out at room temperature for 12 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated with 1000 mL of distilled water. The obtained solid was filtered, washed with water, and then dried under vacuum to obtain 7.7 g of compound (M-3).

[0280] [Synthetic Examples 1-4: Synthesis of Compound (M-4)]

[0281] The following procedure was followed to synthesize compound (M-4).

[0282] [Chemistry 33]

[0283]

[0284] Compound (M-4-1) was synthesized in 5.2 g according to the method described in "Macromolecules 2003, 36, 4385-4396". Subsequently, two drops of N,N-dimethylformamide were added to 5.00 g of compound (M-4-1) and 9 mL of thionyl chloride, and the mixture was reacted at 80 °C for 2 hours. After the reaction, the thionyl chloride was removed under reduced pressure to obtain 5.2 g of compound (M-4-2).

[0285] In Synthesis Examples 1-3, compounds (M-4-2) and (M-4-3) were used instead of 3,5-dinitrobenzoyl chloride and compound (M-3-1), respectively. Otherwise, 4.8 g of compound (M-4) was obtained by the same method as in Synthesis Examples 1-3.

[0286] [Synthetic Examples 1-5: Synthesis of Compound (M-5)]

[0287] The following procedure was followed to synthesize compound (M-5).

[0288] [Chemistry 34]

[0289]

[0290] Compound (M-5-1) was synthesized in 6.1 g according to the method described in the Canadian Journal of Chemistry (Can.J.Chem.), 1985, 63, 2589-2596. Subsequently, two drops of N,N-dimethylformamide were added to 5.00 g of (2,4-dinitrophenyl)-acetic acid and 16 mL of thionyl chloride, and the mixture was reacted at 80 °C for 2 h. After the reaction, the thionyl chloride was removed under reduced pressure to obtain 5.0 g of compound (M-5-2).

[0291] In Synthesis Examples 1-3, compounds (M-5-2) and (M-5-1) were used instead of 3,5-dinitrobenzoyl chloride and compound (M-3-1), respectively. Otherwise, 5.3 g of compound (M-5) was obtained by the same method as in Synthesis Examples 1-3.

[0292] [Synthetic Examples 1-6: Synthesis of Compound (M-6)]

[0293] The following procedure was followed to synthesize compound (M-6).

[0294] [Chemistry 35]

[0295]

[0296] 5.00 g of compound (M-1-1) was dissolved in 50 mL of tetrahydrofuran, followed by the addition of 3.92 g of potassium carbonate and 2.96 g of 2-bromoethanol. The mixture was heated under reflux for 12 hours. After cooling to room temperature, the solvent was removed using a rotary evaporator. 50 mL of ethyl acetate and 50 mL of 2 equivalents of sodium hydroxide were added, and the mixture was stirred at room temperature for 1 hour. The mixture was then purified twice by liquid-liquid extraction using 1 equivalent of hydrochloric acid and twice by liquid-liquid extraction using water. The separated organic layer was distilled under reduced pressure to remove the solvent and dried, yielding 4.3 g of compound (M-6-1).

[0297] Subsequently, 4.0 g of compound (M-6-1) and 2.1 g of triethylamine were dissolved in 40 mL of tetrahydrofuran. A solution prepared by dissolving 3.31 g of 2,4-dinitrofluorobenzene in 40 mL of tetrahydrofuran was added dropwise, and the reaction was allowed to proceed at room temperature for 8 hours. After the reaction, the reaction solution was reprecipitated using 800 mL of distilled water. The obtained solid was filtered, washed with water and ethanol, and then dried under vacuum to obtain 5.1 g of compound (M-6-2).

[0298] 5.0 g of compound (M-6-2), 0.79 g of 5% palladium on carbon, 25 mL of tetrahydrofuran, and 25 mL of ethanol were added, and the mixture was heated to 80 °C. Then, 3.73 g of hydrazine monohydrate was added dropwise, and the mixture was heated under reflux for 6 hours. After cooling to room temperature, the filtered reaction solution was reprecipitated using 500 mL of distilled water. The obtained solid was filtered, washed with water, and then dried under vacuum to obtain 3.7 g of compound (M-6).

[0299] [Synthetic Examples 1-7: Synthesis of Compound (M-7)]

[0300] The following procedure was followed to synthesize compound (M-7).

[0301] [Chemistry 36]

[0302]

[0303] Compound (M-7-1) was synthesized according to the method described in Tetrahedron Letters (Tetrahedron Lett.) 2001, 42, 4001-4003, yielding 6.5 g of compound (M-7-1). Subsequently, 5.00 g of compound (M-7-1) was dissolved in 50 mL of tetrahydrofuran, followed by the addition of 3.92 g of potassium carbonate and 3.62 g of 4-bromo-1-butanol, and the mixture was heated under reflux for 12 hours. After cooling to room temperature, the solvent was removed using a rotary evaporator. Then, 50 mL of ethyl acetate and 50 mL of 2 equivalents of sodium hydroxide were added, and the mixture was stirred at room temperature for 1 hour. The mixture was then purified twice by liquid-liquid extraction using 1 equivalent of hydrochloric acid and twice by liquid-liquid extraction using water. The separated organic layer was distilled under reduced pressure to remove the solvent and dried, yielding 4.8 g of compound (M-7-2).

[0304] In Synthesis Examples 1-3, compound (M-7-2) was used instead of compound (M-3-1). Otherwise, 4.8 g of compound (M-7) was obtained by the same method as in Synthesis Examples 1-3.

[0305] [Synthetic Examples 1-8: Synthesis of Compound (M-8)]

[0306] The following procedure was followed to synthesize compound (M-8).

[0307] [Chemistry 37]

[0308]

[0309] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 38.70 g of cyclohexanone were dissolved in 100 mL of acetonitrile and reacted at 45 °C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice using 100 mL of 1 equivalent hydrochloric acid and twice using 100 mL of water. The organic layer was concentrated using an evaporator, and then thermally recrystallized by adding hexane. The obtained solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 12.3 g of compound (M-8-1).

[0310] In Synthesis Examples 1-3, compound (M-8-1) was used instead of compound (M-3-1). Otherwise, 5.3 g of compound (M-8) was obtained by the same method as in Synthesis Examples 1-3.

[0311] [Synthetic Examples 1-9: Synthesis of Compound (M-9)]

[0312] The following procedure was followed to synthesize compound (M-9).

[0313] [Chemistry 38]

[0314]

[0315] 10.00 g of 2,5-dihydroxyacetophenone, 11.12 g of pyrrolidine, and 45.0 g of heptanal were dissolved in 100 mL of acetonitrile and reacted at 45 °C for 10 hours. After the reaction, 100 mL of ethyl acetate was added, and the mixture was separated twice using 100 mL of 1 equivalent hydrochloric acid and twice using 100 mL of water. The organic layer was concentrated using an evaporator, and then thermally recrystallized by adding hexane. The obtained solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 12.7 g of compound (M-9-1).

[0316] In Synthesis Examples 1-3, compound (M-9-1) was used instead of compound (M-3-1). Otherwise, 5.8 g of compound (M-9) was obtained by the same method as in Synthesis Examples 1-3.

[0317] [Synthetic Examples 1-10: Synthesis of Compound (M-10)]

[0318] The following procedure was followed to synthesize compound (M-10).

[0319] [Chemistry 39]

[0320]

[0321] 4.17 g of 4-(chloromethyl)styrene, 5.00 g of compound (M-1-1), and 9.0 g of potassium carbonate were dissolved in 80 mL of dimethylformamide and reacted at 60 °C for 12 hours. After the reaction was complete, the reaction solution was added dropwise to 800 mL of distilled water, and the resulting solid was collected by filtration. Then, recrystallization was performed using THF solvent, and the obtained solid was collected by filtration and drying to obtain 6.7 g of compound (M-10).

[0322] [Synthetic Example 1-11: Synthesis of Compound (M-11)]

[0323] The following procedure was followed to synthesize compound (M-11).

[0324] [Chemistry 40]

[0325]

[0326] 7.00 g of 2,5-dihydroxyacetophenone, 7.79 g of pyrrolidine, and 8.82 g of 4-phenylcyclohexanone were dissolved in 50 mL of N,N-dimethylformamide and reacted at 100 °C for 24 hours. After the reaction, 200 mL of ethyl acetate was added, and the mixture was separated twice using 100 mL of 1 equivalent hydrochloric acid and twice using 100 mL of water. The organic layer was concentrated using an evaporator, and then thermally recrystallized by adding hexane. The obtained solid was filtered, washed with 2-propanol, and dried under vacuum to obtain 11.3 g of compound (M-11-1).

[0327] In Synthesis Examples 1-10, compound (M-11-1) was used instead of compound (M-1-1), and otherwise, 7.5 g of compound (M-11) was obtained by the same method as in Synthesis Examples 1-10.

[0328] <Synthesis of Polymers>

[0329] 1. Synthesis of polyimide

[0330] [Synthesis example 2-1]

[0331] 100 moles of compound (TA-1) as a tetracarboxylic dianhydride, 10 moles of compound (DA-4) as a diamine, 40 moles of compound (DA-7), 20 moles of compound (DA-8), and 30 moles of compound (M-1) were dissolved in 170 g of N-methyl-2-pyrrolidone (NMP), and the reaction was carried out at 40 °C for 24 hours to obtain a solution containing 20% ​​by mass of polyamic acid. Subsequently, NMP was added to the obtained polyamic acid solution, along with pyridine and acetic anhydride, each in 1.8 molar equivalents relative to the carboxyl groups of the tetracarboxylic dianhydride derived from the polyamic acid, and a dehydration and ring-closing reaction was carried out at 80 °C for 4 hours. Following the dehydration and ring-closing reaction, the solvent in the system was replaced with fresh NMP, followed by concentration, to obtain a solution containing 15% by mass of polyimide with an imidization rate of 70% (designated as polymer (PI-1)). A small amount of the solution was aliquoted and NMP was added to prepare a 10% by mass solution, the viscosity of which was measured to be 42 mPa·s.

[0332] The obtained polymer solution was then injected into a large amount of excess methanol to precipitate the reaction product. The precipitate was washed with methanol and dried under reduced pressure at 40°C for 15 hours to obtain the polymer (PI-1).

[0333] [Synthesis Example 2-3 to Synthesis Example 2-10, Synthesis Example 2-12 to Synthesis Example 2-15]

[0334] As described in Table 1, the types and amounts of tetracarboxylic dianhydride and diamine used in the polymerization were changed. Except for this, the polymerization was carried out in the same manner as in Synthesis Example 2-1, yielding polymers (PI-2) to (PI-10), and polymers (PI-12) to (PI-15) as polyimides. Furthermore, in Table 1, the values ​​for tetracarboxylic dianhydride represent the proportion (molar parts) of each compound relative to 100 molar parts of the total tetracarboxylic dianhydride used in the synthesis. The values ​​for diamine represent the proportion (molar parts) of each compound relative to 100 molar parts of the total diamine used in the synthesis.

[0335] 2. Synthesis of polyamic acid

[0336] [Synthesis example 2-2]

[0337] 100 moles of compound (TA-1) as a tetracarboxylic dianhydride, 50 moles of compound (DA-3) as a diamine, 20 moles of compound (DA-7) and 30 moles of compound (M-2) were dissolved in 170 g of NMP and reacted at 60 °C for 8 hours to obtain a solution containing 20% ​​by mass of a polymer (PI-2) as a polyamic acid. The viscosity of the solution was 39 mPa·s.

[0338] [Synthesis Example 2-11, Synthesis Example 2-16 to Synthesis Example 2-19]

[0339] As described in Table 1, the types and amounts of tetracarboxylic dianhydride and diamine used in the polymerization were changed. Otherwise, the polymerization was carried out in the same manner as in Synthesis Example 2-2, and polymers (PI-11), (PI-16) to (PI-19) as polyamic acid were obtained.

[0340] [Table 1]

[0341]

[0342] 3. Synthesis of addition polymers

[0343] [Synthesis Example 3-1]

[0344] Under nitrogen atmosphere, 30 moles of compound (E-1), 20 moles of compound (E-4), 20 moles of compound (E-5), and 30 moles of compound (M-10) as monomers, 2 moles of 2,2'-azobis(2,4-dimethylpentanones) as a free radical polymerization initiator (relative to 100 moles of monomers), and 50 mL of tetrahydrofuran as solvent were added to a 100 mL two-necked flask, and polymerization was carried out at 70 °C for 6 hours. Furthermore, the total molar amount of monomers was set to 50 mmol for the polymerization reaction. After reprecipitation in n-hexane, the precipitate was filtered and vacuum dried at room temperature for 8 hours to obtain the target polymer (ACR-1). The weight-average molecular weight (Mw), determined by GPC-based polystyrene conversion, was 47,700, and the molecular weight distribution (Mw / Mn) was 2.0.

[0345] [Synthesis example 3-2]

[0346] The monomers were selected according to the types and molar ratios shown in Table 2, and polymerization was carried out in the same manner as in Synthesis Example 3-1 to obtain a polymer (ACR-2) with the same weight average molecular weight and molecular weight distribution as polymer (ACR-1). Furthermore, the total molar amount of monomers was set to 50 mmol, as in Synthesis Example 3-1. The values ​​in Table 2 represent the amount (mol%) of each monomer relative to all monomers used in the synthesis of the polymer.

[0347] [Table 2]

[0348]

[0349] 4. Synthesis of Polyorganosiloxanes

[0350] [Synthesis Example 4-1]

[0351] 90.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 500 g of methyl isobutyl ketone, and 10.0 g of triethylamine were added to a 1000 ml three-necked flask and mixed at room temperature. Then, 100 g of deionized water was added dropwise over 30 minutes using a self-dropping funnel, and the mixture was stirred under reflux at 80 °C for 6 hours. After the reaction was complete, the organic layer was removed and washed with a 0.2% ammonium nitrate aqueous solution until the washing water was neutral. The solvent and water were then removed by distillation under reduced pressure. An appropriate amount of methyl isobutyl ketone was added to obtain a 50% solution (ESSQ-1) as a polymer of an epoxy-containing polyorganosiloxane.

[0352] In a 500 ml three-necked flask, 18.68 g of compound (C-1) (30 mol% relative to the amount of epoxy groups in the polymer (ESSQ-1), 4.00 g of tetrabutylammonium bromide, 80 g of a solution containing polymer (ESSQ-1), and 294 g of methyl isobutyl ketone were added, and the mixture was stirred at 90 °C for 18 hours. After cooling to room temperature, the mixture was subjected to 10 separate washing operations using distilled water. The organic layer was then recovered, and after two rounds of concentration and NMP dilution using a rotary evaporator, the solution was adjusted with NMP to a solids concentration of 10% by mass to obtain an NMP solution of polymer (PS-1).

[0353] [Chemistry 41]

[0354]

[0355] <Preparation and Evaluation of Liquid Crystal Alignment Agents>

[0356] [Example 1]

[0357] (1) Preparation of liquid crystal alignment agent (AL-1)

[0358] To 100 parts by mass of the polymer (PI-1) obtained in Synthesis Example 2-1, 5 parts by mass of the polymer (PS-1) obtained in Synthesis Example 4-1, 10 parts by mass of the compound (Add-1) as a crosslinking agent, and NMP and butyl cellosolve (BC) as solvents were added to prepare a solution with a solvent composition of NMP / BC = 50 / 50 (mass ratio) and a solid content concentration of 4.0% by mass. The solution was filtered using a filter with a pore size of 0.2 μm to prepare the liquid crystal alignment agent (AL-1).

[0359] (2) Preparation of liquid crystal compositions

[0360] To obtain liquid crystal composition LC1, 5% by mass of a liquid crystal compound represented by formula (L1-1) and 0.3% by mass of a photopolymerizable compound represented by formula (L2-1) were added to 10g of nematic liquid crystal (Merck, MLC-6608) and mixed.

[0361] [Chemistry 42]

[0362]

[0363] (3) Manufacturing of PSA type liquid crystal display elements

[0364] Using a liquid crystal alignment film printing machine (manufactured by Nippon Shashin Printing Co., Ltd.), the liquid crystal alignment agent (AL-1) prepared above was coated onto the electrode surfaces of two glass substrates, each having a conductive film including ITO electrodes patterned into slit shapes. After removing the solvent by heating on a hot plate at 80°C for 2 minutes (pre-baking), the substrates were then heated on a hot plate at 230°C for 30 minutes (post-baking) to form a coating with an average film thickness of 100 nm. These coatings were then ultrasonically cleaned in ultrapure water for 1 minute and dried in a clean oven at 100°C for 10 minutes, thereby obtaining a pair (two pieces) of substrates with liquid crystal alignment films. Furthermore, the electrode pattern used is the same as the electrode pattern in the PSA mode.

[0365] Next, an epoxy resin adhesive containing alumina spheres with a diameter of 5.5 μm is applied to the outer edge of the surface of one of the pair of substrates with the liquid crystal alignment film. Then, the substrates are overlapped and pressed together with the liquid crystal alignment film surfaces facing each other, and the adhesive is allowed to harden. Next, the liquid crystal composition LC1 prepared above is filled between the pair of substrates through the liquid crystal injection port, and the liquid crystal injection port is sealed using an acrylic photocurable adhesive, thereby manufacturing a liquid crystal cell. Then, with the liquid crystal driven by a 10V AC current at a frequency of 60Hz applied between the conductive films of the liquid crystal cell, an ultraviolet irradiation device using a metal halide lamp as the light source is used at 100,000 J / m². 2 The ultraviolet light is irradiated with an irradiation dose. Furthermore, the irradiation dose is a value measured using a photometer with a wavelength of 365 nm as a reference. Then, polarizing plates are attached to the outer two sides of the substrate with their polarization directions orthogonal to each other and at a 45° angle to the projection direction of the ultraviolet light axis of the liquid crystal alignment film onto the substrate surface, thereby manufacturing a PSA-type liquid crystal display element.

[0366] (4) Evaluation of the pre-tilt angle

[0367] For the liquid crystal display element manufactured in (2), the angle at which the liquid crystal molecules tilt from the substrate surface is determined by using the crystallization rotation method of He-Ne laser light, according to the method described in the non-patent literature (TJ Cheffer et al., Journal of Applied Physics, J. Appl. Phys., vo. 19, p. 2013 (1980)). This value is set as the pretilt angle. At this time, a pretilt angle of 88.5 degrees or less is set as "good (○)", a pretilt angle of more than 88.5 degrees and less than 89.0 degrees is set as "acceptable (△)", and a pretilt angle of more than 89.0 degrees is set as "poor (×)". As a result, in this embodiment, the evaluation is "good (○)".

[0368] (5) Evaluation of narrow-line tightness

[0369] Liquid crystal alignment agent (AL-1) was applied to a glass substrate using a spinner. After pre-baking at 80°C for 2 minutes, the substrate was heated for 30 minutes in a 230°C oven purged with nitrogen (post-baking) to form a coating with an average thickness of 0.10 μm. This process was repeated to create two coated glass substrates. On the coating of one glass substrate, an ODF sealant (manufactured by Sekisui Chemicals, S-WB42) was applied with a width of 0.5 mm (i.e., a sealing width of 0.5 mm). The other glass substrate was then bonded together with its coating in contact with the ODF sealant. The substrate was then irradiated with a metal halide lamp at 30,000 J / m². 2 After being exposed to light (converted to 365nm), the wires were heated in an oven at 120°C for 1 hour. Then, the bonding strength was measured using a tensile and compression testing machine (model: SDWS-0201-100SL) from Imada Manufacturing Co., Ltd., thereby evaluating the narrow wire bonding performance. In the evaluation, a bonding strength of 175 N / cm was used. 2 The above conditions are set as "Excellent (◎)", and the contact strength is set at 160 N / cm. 2 Above and less than 175 N / cm 2 The condition is set to "Good (○)", and the contact force is set to 150 N / cm. 2 Above and below 160 N / cm 2 The condition is set to "allowable (△)", and the contact force is less than 150 N / cm. 2 The condition is set as "Poor (×)". As a result, in this embodiment, the contact force is 180 N / cm. 2 The narrow-line tightness is rated as "particularly good (◎)".

[0370] (6) Evaluation of long-term thermal reliability

[0371] Without attaching polarizing plates to the outer two sides of the substrate, the same operation as described in (3) was performed to manufacture a PSA-type liquid crystal cell. For the PSA-type liquid crystal cell, a voltage of 5V was applied for a duration of 60 microseconds and a span of 167 milliseconds, and the voltage retention rate was measured from the time the application was removed until 167 milliseconds later. The measuring apparatus used was a VHR-1 manufactured by TOYO Corporation.

[0372] In addition, the voltage retention rate was measured again after the obtained liquid crystal cells were stored in a constant temperature bath at 100°C for 21 days (approximately 500 hours). The long-term thermal reliability (i.e., reliability to withstand long-term high-temperature use) of the liquid crystal cells was evaluated based on the decrease in voltage retention rate caused by storage in the 100°C constant temperature bath (voltage retention rate after liquid crystal cell manufacturing (%) - voltage retention rate after storage in the constant temperature bath (%)). In the evaluation, a voltage retention rate decrease of less than 15% was designated as "Excellent (◎)", a decrease of 15% or more but less than 25% was designated as "Good (○)", a decrease of 25% or more but less than 40% was designated as "Acceptable (△)", and a decrease of 40% or more was designated as "Poor (×)". In this example, the evaluation is "Good (○)".

[0373] (7) Evaluation of high temperature and high humidity resistance

[0374] The PSA-type liquid crystal display element manufactured by the method described in (3) was stored in an oven set at 60°C and 90% humidity for 300 hours, and the voltage retention rate was measured in the same manner as in (6). This value was set as VHR2, and the voltage retention rate measured before storage under high temperature and high humidity conditions of 60°C and 90% humidity was set as VHR1. The reduction in voltage retention rate ΔVHR was calculated by subtracting VHR1 from VHR2, and the high temperature and high humidity resistance was evaluated based on ΔVHR. A ΔVHR less than 5% was designated as "Excellent (◎)", a ΔVHR of 5% or more but less than 10% was designated as "Good (○)", a ΔVHR of 10% or more but less than 20% was designated as "Acceptable (△)", and a ΔVHR of 20% or more was designated as "Poor (×)". In this embodiment, the evaluation was "Excellent (◎)".

[0375] [Examples 2 to 13 and Comparative Examples 1 to 4]

[0376] As shown in Table 3, the formulation composition was modified. Except for this, liquid crystal alignment agents (AL-2) to (AL-9) and (AR-1) to (AR-4) were prepared using the same solvent composition and solid component concentration as in Example 1. Furthermore, PSA-type liquid crystal display elements were manufactured using each liquid crystal alignment agent in the same manner as in Example 1, and various evaluations were performed. The evaluation results are shown in Table 3. In Table 3, the parts of polymer and crosslinking agent are expressed as parts by mass.

[0377] [Table 3]

[0378]

[0379] As can be seen from the results of the above embodiments, in the liquid crystal alignment agents of Examples 1 to 13 containing polymer (P), the pretilt angle characteristics, narrow line adhesion, long-term thermal reliability, and high temperature and humidity resistance are improved in a balanced manner. In particular, R in the above formula (1) is used. 1 and R 2 The polymers (P) with substituents in Examples 1, 4 to 13 have excellent resistance to high temperature and high humidity, which is rated as "particularly good".

[0380] In contrast, in Comparative Examples 1 to 4, which do not contain polymer (P), the narrow-line tightness, long-term thermal reliability, and resistance to high temperature and humidity are worse than those of Examples 1 to 13. Furthermore, Comparative Examples 3 and 4 also show worse pretilt angle characteristics than Examples 1 to 13. Furthermore, in Comparative Examples 1 to 3, where polymers (PI-12), (PI-13), and (ACR-2) with chromone structures but different substituents were used instead of polymer (P), the narrow-line tightness, long-term thermal reliability, and high-temperature and high-humidity resistance were insufficient. The reason for this is presumably that, compared with polymers (PI-1) to (PI-8), (PI-14) to (PI-17), and (ACR-1) used in Examples 1 to 13, polymers (PI-12), (PI-13), and (ACR-2) have larger side chain structures, thus reducing film density or side chain entanglement.

Claims

1. A liquid crystal alignment agent comprising a polymer (P) having a partial structure represented by the following formula (1), In equation (1), R 1 and R 2 Each is independently an alkyl group having 1 to 3 carbon atoms; X 1 It is a single bond, an alkyl diyl group with 1 to 6 carbon atoms, -O-, or -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 ;a is an integer from 1 to 6;b is an integer from 0 to 6;"* 1 "" indicates a bond with the benzene ring in formula (1); "*" indicates a bond.

2. The liquid crystal alignment agent according to claim 1, wherein, The polymer (P) is at least one selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, polyamide, polyorganosiloxane and addition polymers.

3. The liquid crystal alignment agent according to claim 1, wherein, The polymer (P) comprises structural units derived from a diamine having a partial structure represented by the formula (1).

4. The liquid crystal alignment agent according to claim 3, wherein, The diamine is at least one selected from the group consisting of compounds represented by formula (2-1) and compounds represented by formula (2-2). In equations (2-1) and (2-2), Ar 1 and Ar 3 Each is independently a trivalent aromatic cyclic group; Ar 2 and Ar 4 Each is independently a divalent aromatic cyclic group; X 2 and X 3 Each is independently a single bond, -O-, -CH2-, -CO-, -NR. 3 -、-COO-、-OCO-、-CONR 3 -or-NR 3 CO-;R 3 It is a hydrogen atom or a monovalent organic group; R 1 R 2 and X 1 This has the same meaning as the above equation (1).

5. The liquid crystal alignment agent according to claim 1 further comprises a polymer that does not have the partial structure represented by formula (1).

6. The liquid crystal alignment agent according to claim 1, wherein, The polymer (P) comprises structural units derived from monomers having at least one partial structure selected from the group consisting of nitrogen-containing heterocycles, amino groups, protected amino groups, amide groups, protected amide groups, urea groups, and protected urea groups.

7. The liquid crystal alignment agent according to claim 1, wherein, The polymer (P) comprises structural units derived from monomers having at least one of the following groups in which the side chain is selected from alkyl groups having 4 to 30 carbon atoms, halogenated alkyl groups having 4 to 30 carbon atoms, alkoxy groups having 4 to 30 carbon atoms, halogenated alkoxy groups having 4 to 30 carbon atoms, polycyclic structures having two or more rings directly or through divalent linkages, and groups having a steroid backbone, and does not have the partial structure represented by formula (1).

8. A liquid crystal alignment film formed using a liquid crystal alignment agent as described in any one of claims 1 to 7.

9. A liquid crystal element comprising the liquid crystal alignment film as described in claim 8.

10. A method for manufacturing a liquid crystal element, comprising: The process of forming a coating by coating a liquid crystal alignment agent as described in any one of claims 1 to 7 onto each of the conductive films in a pair of substrates having conductive films; The process of constructing a liquid crystal cell by arranging a pair of substrates with the coating formed thereon facing each other with the coating separated by a liquid crystal layer. as well as The process of irradiating the liquid crystal cell with light while applying a voltage between the conductive films.

11. An polymer having a partial structure represented by the following formula (1), In equation (1), R 1 and R 2 Each is independently an alkyl group having 1 to 3 carbon atoms; X 1 It is a single bond, an alkyl diyl group with 1 to 6 carbon atoms, -O-, or -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 ;a is an integer from 1 to 6;b is an integer from 0 to 6;"* 1 "" indicates a bond with the benzene ring in formula (1); "*" indicates a bond.

12. A diamine, represented by the following formula (2-1), In equation (2-1), R 1 and R 2 Each is independently an alkyl group having 1 to 3 carbon atoms; X 1 -O-, -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 ;a is an integer from 1 to 6;b is an integer from 0 to 6;"* 1 " represents the bond with the benzene ring in formula (2-1); Ar 1 It is a trivalent, unsubstituted benzene ring.

13. A diamine, represented by the following formula (2-2), In equation (2-2), R 1 and R 2 Each is independently an alkyl group having 1 to 3 carbon atoms; X 1 -O-, -CH2-O-* 1 -O-(CH2) a -O-、-(CH2) b -COO-* 1 -(CH2) b -COO-(CH2) a -O-* 1 or -O-CO-* 1 ;a is an integer from 1 to 6;b is an integer from 0 to 6;"* 1 " represents the bond with the benzene ring in formula (2-2); Ar 2 and Ar 4 Each is an independent divalent, unsubstituted benzene ring; Ar 3 It is a trivalent, unsubstituted benzene ring; X 2 and X 3 They can be independently -O-, -CH2-, or -NH-.

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