JP2023064669A - Liquid crystal alignment agent, liquid crystal alignment film and manufacturing method for the same, and liquid crystal element - Google Patents

Abstract

To provide a liquid crystal alignment agent with which it is possible to form a liquid crystal alignment film having high dynamic strength.SOLUTION: A polymer [P] having a partial structure expressed by formula (1) is included in a liquid crystal alignment agent. In formula (1), B1 and B2 are a single bond or a divalent organic group independently of each other. J1 is a divalent group including a region that is cleaved by stimulus. m is 0 or 1. When m=1, X1 is a cross-linking group; when m=0, X1 is a group that forms an inclusion complex by mutual action with the polymer [P] or a group Z1 that a compound different from the polymer [P] has, with the inclusion complex being separable by stimulus. n is an integer 1-3. [*] represents a bond.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a liquid crystal aligning agent, a liquid crystal aligning film, a method for producing the same, and a liquid crystal element.

A liquid crystal element includes a liquid crystal alignment film having a function of aligning liquid crystal molecules in a liquid crystal layer in a predetermined direction. A liquid crystal alignment film is generally formed on a substrate by applying a liquid crystal alignment agent obtained by dissolving a polymer component in an organic solvent on the surface of the substrate, and preferably by heating.

In recent years, large-screen, high-definition liquid crystal televisions have become mainstream, and small display terminals such as smartphones and tablet PCs have become popular, and the demand for higher quality of liquid crystal elements is increasing. In view of these points, various liquid crystal aligning agents have been proposed in order to improve various characteristics of liquid crystal elements by improving liquid crystal alignment films (see, for example, Patent Document 1). Patent Literature 1 discloses that a liquid crystal aligning agent contains a cross-linking agent having a structure in which a methylol group is bonded to an aromatic ring together with a polyimide or a polyimide precursor.

WO2010/074269

As the definition of the liquid crystal element becomes higher, the demand for quality becomes more severe. Considering the application of rubbing treatment, the improvement of liquid crystal orientation and voltage retention, the suppression of yield reduction, and the suppression of film breakage at the sealant portion, the liquid crystal alignment film has high mechanical strength. is required.

The present invention has been made in view of the above problems, and a main object thereof is to provide a liquid crystal aligning agent capable of forming a liquid crystal aligning film having high mechanical strength.

（式（１）中、Ｂ^１及びＢ^２は、それぞれ独立して、単結合又は２価の有機基である。Ｊ^１は、刺激により開裂する部位を含む２価の基である。ｍは０又は１である。ｍが１の場合、Ｘ^１は架橋性基であり、ｍが０の場合、Ｘ^１は、重合体［Ｐ］又は重合体［Ｐ］とは異なる化合物が有する基Ｚ^１との相互作用により包接体を形成し、刺激により前記包接体が分離され得る基である。ｎは１～３の整数である。「＊」は結合手を表す。）
［２］ 上記［１］の液晶配向剤を用いて形成された液晶配向膜。
［３］ 上記［２］の液晶配向膜を具備する液晶素子。
［４］ 上記［１］の液晶配向剤を基板上に塗布する工程と、前記基板上の液晶配向剤に含まれる重合体を架橋させる工程と、架橋された重合体に刺激を付与することにより重合体間の結合又は相互作用を切断する工程と、を含む、液晶配向膜の製造方法。
［５］ 下記式（１Ａ）で表される部分構造を有する重合体。

（式（１Ａ）中、Ｂ^１及びＢ^２は、それぞれ独立して、単結合又は２価の有機基である。Ｊ^１は、刺激により開裂する部位を含む２価の基である。Ｘ^１は架橋性基である。ｎは１～３の整数である。「＊」は結合手を表す。） According to the present invention, the following means are provided.
[1] A liquid crystal aligning agent containing a polymer [P] having a partial structure represented by the following formula (1).

(In formula (1), B ¹ and B ² are each independently a single bond or a divalent organic group. J ¹ is a divalent group containing a site that cleaves upon stimulation. m is 0 or 1. When m is 1, X ¹ is a crosslinkable group, and when m is 0, X ¹ is a group Z possessed by the polymer [P] or a compound different from the polymer [P] A group that forms a clathrate by interaction with ¹ and can be separated from the clathrate by stimulation.n is an integer of 1 to 3. "*" represents a bond.)
[2] A liquid crystal alignment film formed using the liquid crystal alignment agent of [1] above.
[3] A liquid crystal device comprising the liquid crystal alignment film of [2] above.
[4] A step of applying the liquid crystal aligning agent of [1] above on a substrate, a step of cross-linking a polymer contained in the liquid crystal aligning agent on the substrate, and applying a stimulus to the cross-linked polymer. and a step of cutting bonds or interactions between polymers.
[5] A polymer having a partial structure represented by the following formula (1A).

(In formula (1A), B ¹ and B ² are each independently a single bond or a divalent organic group. J ¹ is a divalent group containing a site that cleaves upon stimulation. X ¹ is a crosslinkable group, n is an integer of 1 to 3, and "*" represents a bond.)

According to the liquid crystal aligning agent of the present invention, a polymer having a partial structure represented by the above formula (1) and two groups capable of forming a bond or interacting with the group X ¹ in the above formula (1) A liquid crystal alignment film having high mechanical strength can be formed by containing the compound having the above.

（式（１）中、Ｂ^１及びＢ^２は、それぞれ独立して、単結合又は２価の有機基である。Ｊ^１は、刺激により開裂する部位を含む２価の基である。ｍは０又は１である。ｍが１の場合、Ｘ^１は架橋性基であり、ｍが０の場合、Ｘ^１は、重合体［Ｐ］又は重合体［Ｐ］とは異なる化合物が有する基Ｚ^１との相互作用により包接体を形成し、刺激により前記包接体が分離され得る基である。ｎは１～３の整数である。「＊」は結合手を表す。） ≪Liquid crystal aligning agent≫
The liquid crystal aligning agent of the present disclosure contains a polymer [P] having a partial structure represented by formula (1) below.

(In formula (1), B ¹ and B ² are each independently a single bond or a divalent organic group. J ¹ is a divalent group containing a site that cleaves upon stimulation. m is 0 or 1. When m is 1, X ¹ is a crosslinkable group, and when m is 0, X ¹ is a group Z possessed by the polymer [P] or a compound different from the polymer [P] A group that forms a clathrate by interaction with ¹ and can be separated from the clathrate by stimulation.n is an integer of 1 to 3. "*" represents a bond.)

Here, the present inventors form a crosslinked structure (three-dimensional network structure) by covalent bonding or physical interaction (for example, hydrogen bonding) in the polymer network formed in the film by the liquid crystal aligning agent, After that, if the intermolecular bonds formed by the cross-linking reaction are cut, a plurality of homogeneously mixed independent polymer networks can be formed, and the mechanical strength of the liquid crystal alignment film can be improved. As a result of intensive studies based on this conjecture, it has become clear that the liquid crystal alignment agent containing the polymer [P] can improve the mechanical strength of the liquid crystal alignment film. Below, each component contained in a liquid crystal aligning agent and the other component mix|blended arbitrarily as needed are demonstrated.

As used herein, the term "hydrocarbon group" includes a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group. A "chain hydrocarbon group" means a straight chain hydrocarbon group or a branched hydrocarbon group that does not contain a cyclic structure in its main chain and is composed only of a chain structure. However, it may be saturated or unsaturated. The “alicyclic hydrocarbon group” means a hydrocarbon group containing only an alicyclic hydrocarbon structure as a ring structure and not containing an aromatic ring structure. However, it does not have to be composed only of an alicyclic hydrocarbon structure, and includes those having a chain structure in part thereof. An "aromatic hydrocarbon group" means a hydrocarbon group containing an aromatic ring structure as a ring structure. However, it does not have to be composed only of an aromatic ring structure, and may partially contain a chain structure or an alicyclic hydrocarbon structure.

<Polymer [P]>
In the above formula (1), the divalent organic groups represented by B ¹ and B ² may be groups capable of connecting the partial structure represented by the above formula (1) to the main skeleton of the polymer. , is not particularly limited. Specific examples of the divalent organic groups represented by B ¹ and B ² include -COO-, -OCO-, -CONR ¹ -, -NR ¹ CO-, and divalent hydrocarbons having 1 to 30 carbon atoms. -O-, -S-, -CO-, -COO-, -OCO-, -NR ¹ under the condition that any methylene groups in a group, a divalent hydrocarbon group having 2 to 30 carbon atoms are not adjacent to each other A divalent group substituted with -, -CONR ¹ - or -NR ¹ CO- may be mentioned. R ¹ is a hydrogen atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms or a thermally eliminable group. The thermally leaving group is preferably a carbamate-based leaving group, more preferably a tert-butoxycarbonyl group.

The divalent group represented by ^J1 contains a stimulus-cleaved site. The stimulus for causing cleavage at the site containing ^J1 is not particularly limited, but in that the stimulus can be efficiently applied from the outside to the film formed by the liquid crystal aligning agent, at least any one of light, heat and magnetic field is preferable, and at least one of light and heat is more preferable in terms of ease of application.

When J ¹ contains a site that is cleaved by heat, J ¹ is, for example, a group having a partial structure that is cleaved upon induction of a Diels-Alder reaction, a radical cleavage reaction, a pinacol rearrangement reaction, an exchange reaction, or the like by the application of heat. mentioned. Specific examples thereof include an unsaturated 6-membered ring structure formed by an addition reaction between a conjugated diene and an alkene as a group having a partial structure that is cleaved by inducing a Diels-Alder reaction upon application of heat. . Examples of the group having a partial structure that can be cleaved by inducing a radical cleavage reaction upon application of heat include a disulfide structure, an alkoxyamine structure, and a diarylbiphenylfuranone structure. Examples of the group having a partial structure that is cleaved by inducing an exchange reaction upon application of heat include an oxime ether structure, an enamine structure, a (thio)urea structure, an acetal structure, an aminal structure, an imine structure, and a siloxane structure. In addition, "(thio)urea" is meant to include urea and thiourea.

When J ¹ contains a photocleavable site, examples of J ¹ include groups having a benzyl ester structure, nitrobenzyl structure, methoxyphenyl ether structure or disulfide structure.

When J ¹ is a group containing a site that is cleaved by at least one of light and heat, J ¹ is, among others, an unsaturated 6-membered ring structure formed by an addition reaction of a conjugated diene and an alkene, a disulfide structure, an alkoxy A group having an amine structure, diarylbiphenylfuranone structure, oxime ether structure, enamine structure, (thio)urea structure, acetal structure, aminal structure, imine structure, pinacol structure, benzyl ester structure, nitrobenzyl structure, or methoxyphenyl ether structure. Preferably.

（式（１Ａ）中、Ｂ^１及びＢ^２は、それぞれ独立して、単結合又は２価の有機基である。Ｊ^１は、刺激により開裂する部位を含む２価の基である。Ｘ^１は架橋性基である。ｎは１～３の整数である。「＊」は結合手を表す。）
で表される部分構造を有する。ｍが１の場合、Ｘ^１で表される架橋性基が、重合体［Ｐ］又は重合体［Ｐ］とは異なる化合物が有する基と結合を形成することにより、架橋構造を有する膜を得ることができる。 When m is 1, the polymer [P] has the following formula (1A):

(In formula (1A), B ¹ and B ² are each independently a single bond or a divalent organic group. J ¹ is a divalent group containing a site that cleaves upon stimulation. X ¹ is a crosslinkable group, n is an integer of 1 to 3, and "*" represents a bond.)
It has a partial structure represented by When m is 1, the crosslinkable group represented by X ¹ forms a bond with a group possessed by the polymer [P] or a compound different from the polymer [P] to obtain a film having a crosslinked structure. be able to.

The crosslinkable group represented by ^X1 is preferably a group capable of forming a covalent bond by reacting with heating when forming a film using a liquid crystal aligning agent. In terms of high thermal reactivity, the crosslinkable group represented by X ¹ includes an oxetanyl group, an oxiranyl group, a group having a Meldrum's acid structure, a cyclocarbonate group, a carboxy group, a protected carboxy group, an amino group, a protected amino group, β-hydroxyamide group, carbon-carbon unsaturated bond-containing group, thiol group, protected thiol group, group having a cremone structure, cyanate group, protected isocyanate group, or oxazoline group is preferred. The carbon-carbon unsaturated bond-containing group includes a vinyl group, a (meth)acryloyl group, a maleimide group and the like. In addition, "(meth)acryloyl" is meant to include acryloyl and methacryloyl.

（式中、「＊」は結合手を表す。） When m is 1, specific examples of the partial structure represented by the above formula (1) include, for example, moieties represented by the following formulas (1-2-1) to (1-2-15) structure.

(In the formula, "*" represents a bond.)

When m is 1, the ratio of the partial structure represented by the above formula (1) in the polymer [P] is 2 mol% or more with respect to the total amount of the monomer units constituting the polymer [P]. is preferred, 5 mol % or more is more preferred, and 10 mol % or more is even more preferred. Further, when m is 1, the ratio of the partial structure represented by the above formula (1) is preferably 80 mol% or less, and 70 mol % or less is more preferable. When the proportion of the partial structure represented by the above formula (1) is within the above range, formation of a non-uniform crosslinked structure is suppressed, which is preferable in that it is possible to suppress a decrease in the toughness of the film.

When m is 0, X ¹ forms a clathrate through interaction with the group Z ¹ possessed by the polymer [P] or a compound different from the polymer [P], and the clathrate is separated by stimulation. It is a group to obtain. The clathrate formed by the interaction of X ¹ and Z ¹ is not particularly limited as long as it can be separated by a stimulus. From the point of view, the clathrate formed by the cyclodextrin structure is preferred.

When one of X ¹ and Z ¹ is a group having a cyclodextrin structure, the cyclodextrin structure is a monovalent group. The cyclodextrin structure may have a substituent on the ring portion. Examples of the substituent include an amino group, a thiol group, -OCO-(CH ₂ ) _r COOH, -NH-(CH ₂ ) _r NH ₂ , -NH-(CH ₂ CH ₂ O) _r NH ₂ and the like. .

When one of X ¹ and Z ¹ has a cyclodextrin structure, the other group should be able to form an inclusion body with the cyclodextrin structure and be separable from the cyclodextrin structure by stimulation. Such a group is preferably a group in which an isomerization reaction is induced by light, and includes, for example, a group having an azobenzene structure.

When m is 0, the ratio of the partial structure represented by the above formula (1) in the polymer [P] is 5 mol% or more with respect to the total amount of the monomer units constituting the polymer [P]. is preferred, 10 mol % or more is more preferred, and 30 mol % or more is even more preferred. When the ratio of the partial structure represented by the above formula (1) is within the above range, the clathrate can be sufficiently formed with the compound [A], which is preferable in that the effect of improving the film strength can be enhanced. .

The polymer [P] may have the partial structure represented by the above formula (1) on the side chain of the polymer, or may have it on the end of the polymer. Also, it may be present at both the side chain and terminal of the polymer. Among these, in that the partial structure represented by the above formula (1) can be sufficiently introduced into the polymer, the polymer [P] has the partial structure represented by the above formula (1) at least on the side of the polymer. It is preferred to have it in a chain.

The polymer [P] is a group capable of forming a bond with the group X ¹ in the formula (1) or interacting with the partial structure represented by the formula (1) to form a clathrate. (hereinafter also referred to as “group Y ¹ ”). By having the group X ¹ and the group Y ¹ in one molecule of the polymer [P], a crosslinked structure is formed between the molecules of the polymer [P], and a liquid crystal alignment film having sufficiently high film strength is obtained. It is preferable that

When m is 1, Y ¹ is a group capable of forming a covalent bond with X ¹ (crosslinkable group). Specific examples of Y ¹ when m is 1 include groups capable of forming a covalent bond with any of the groups described above as preferred examples of the crosslinkable group represented by X ¹ .

Preferred combinations of X ¹ and Y ¹ include a combination in which one is an amino group or a protected amino group and the other is an oxetanyl group, an oxiranyl group, a cyclocarbonate group or a cyanate group; is an oxetanyl group, an oxiranyl group, a β-hydroxyamide group or a cyanate group; a combination in which one is a carbon-carbon unsaturated bond-containing group and the other is a thiol group; one is a maleimide group and one is furyl A combination of groups and the like can be mentioned. The combination of X ¹ and Y ¹ is such that one of them is an amino group or a protected amino group, and the other is an oxetanyl group, an oxiranyl group, or a A combination of a cyclocarbonate group or a cyanate group; a combination of one of which is a carboxy group and the other of which is an oxetanyl group, an oxiranyl group, a β-hydroxyamide group or a cyanate group is particularly preferred.

In addition, when m is 0, ^Y1 is synonymous with ^Z1 . For ^Y1 when m is 0, the description of ^Z1 is used.

When m is 1, the proportion of Y ¹ in the polymer [P] is preferably 2 mol% or more, and preferably 5 mol% or more, with respect to the total amount of the monomer units constituting the polymer [P]. More preferably, 10 mol % or more is even more preferable. Further, when m is 0, the proportion of Y ¹ in the polymer [P] is preferably 5 mol% or more, preferably 10 mol%, with respect to the total amount of the monomer units constituting the polymer [P]. The above is more preferable, and 30 mol % or more is even more preferable.

The main chain of polymer [P] is not particularly limited. Polymer [P] is polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, and addition polymers. Among these, the polymer [P] is at least one polymer selected from the group consisting of polyamic acids, polyamic acid esters, polyimides and addition polymers, from the viewpoint of increasing the reliability of the resulting liquid crystal device. It is particularly preferred to include

(polyamic acid)
When the polymer [P] is a polyamic acid, the polyamic acid (hereinafter also referred to as polyamic acid [P]) is, for example, a tetracarboxylic dianhydride and a partial structure represented by the above formula (1). It can be obtained by reacting with a diamine containing a diamine (hereinafter also referred to as “specific diamine”).

・Tetracarboxylic dianhydrides Tetracarboxylic dianhydrides used in the synthesis of polyamic acid [P] include, for example, aliphatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, aromatic tetracarboxylic dianhydrides, Carboxylic acid dianhydride etc. can be mentioned. Specific examples thereof include 1,2,3,4-butanetetracarboxylic dianhydride and the like as the aliphatic tetracarboxylic dianhydride;
As alicyclic tetracarboxylic dianhydrides, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2 , 3,5-tricarboxycyclopentyl acetic acid 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-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride and the like;
As aromatic tetracarboxylic dianhydrides, pyromellitic dianhydride, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride, ethylene glycol bisanhydrotrimate, 4,4'-(hexafluoroisopropylidene 4,4'-Carbonyldiphthalic anhydride, 4,4'-carbonyldiphthalic anhydride, etc.; and tetracarboxylic dianhydrides described in JP-A-2010-97188 can be used. Tetracarboxylic dianhydrides may be used singly or in combination of two or more.

The tetracarboxylic dianhydride used for the synthesis of the polyamic acid [P] is a group consisting of aliphatic tetracarboxylic dianhydrides and alicyclic tetracarboxylic dianhydrides in that the solubility of the polymer can be increased. It preferably contains at least one selected from, and more preferably contains an alicyclic tetracarboxylic dianhydride. The amount of the alicyclic tetracarboxylic dianhydride used is preferably 20 mol% or more, and 40 mol% or more, relative to the total amount of the tetracarboxylic dianhydride used in the synthesis of the polyamic acid [P]. and more preferably 50 mol % or more.

（式（２）中、Ａ^１は３価の芳香環基である。Ｂ^１、Ｂ^２、Ｊ^１、Ｘ^１、ｍ及びｎは上記式（１）と同義である。） - Diamine The specific diamine used for synthesizing the polyamic acid [P] is not particularly limited as long as it has the partial structure represented by the above formula (1). Specific diamines include, for example, compounds represented by the compound represented by the following formula (2).

(In formula (2), A ¹ is a trivalent aromatic ring group. B ¹ , B ² , J ¹ , X ¹ , m and n are as defined in formula (1) above.)

In the above formula (2), the trivalent aromatic ring group represented by ^A1 is a group obtained by removing three hydrogen atoms from the ring portion of the aromatic ring. Examples of the aromatic ring include aromatic hydrocarbon rings such as benzene ring, naphthalene ring and anthracene ring; aromatic heterocycles such as pyridine ring and pyridazine ring. Among these, a benzene ring and a pyridine ring are particularly preferred. A substituent may be introduced into the aromatic ring of the aromatic ring group. Examples of such substituents include alkyl groups having 1 to 3 carbon atoms, halogen atoms, and hydroxyl groups.

Specific examples of the specific diamine include compounds represented by the following formulas (2-1) to (2-11).

The diamine used for synthesizing the polyamic acid [P] may be only the specific diamine, but together with the specific diamine, a diamine having no partial structure represented by the above formula (1) (hereinafter referred to as "other diamine" ) may also be used. Other diamine compounds include aliphatic diamines, alicyclic diamines, aromatic diamines, diaminoorganosiloxanes, and the like.

（式（Ｅ－１）中、Ｘ^I及びＸ^IIは、それぞれ独立して、単結合、－Ｏ－、＊－ＣＯＯ－又は＊－ＯＣＯ－（ただし、「＊」はＸ^Ｉとの結合手を示す。）である。Ｒ^Ｉは、炭素数１～３のアルカンジイル基である。Ｒ^ＩＩは、単結合又は炭素数１～３のアルカンジイル基である。Ｒ^ＩＩＩは、炭素数１～２０のアルキル基、アルコキシ基、フルオロアルキル基、又はフルオロアルコキシ基である。ａは０又は１である。ｂは０～３の整数である。ｃは０～２の整数である。ｄは０又は１である。ただし、１≦ａ＋ｂ＋ｃ≦３である。）
で表される化合物等の側鎖型ジアミン等を；
ジアミノオルガノシロキサンとして、例えば、１，３－ビス（３－アミノプロピル）－テトラメチルジシロキサン等を；それぞれ挙げることができるほか、特開２０１０－９７１８８号公報に記載のジアミンを用いることができる。ポリアミック酸［Ｐ］の合成に際し、ジアミンとしては、１種を単独で又は２種以上を組み合わせて使用することができる。 Specific examples of other diamines include aliphatic diamines such as metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine; alicyclic diamines such as 1,4- diaminocyclohexane, 4,4′-methylenebis(cyclohexylamine) and the like;
As aromatic diamines, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4-aminophenyl-4-aminobenzoate, 4,4'-diaminoazobenzene, 1,5-bis(4-aminophenoxy)pentane, 1 , 2-bis(4-aminophenoxy)ethane, 1,6-bis(4-aminophenoxy)hexane, bis[2-(4-aminophenyl)ethyl]hexanedioic acid, 2,6-diaminopyridine, 1, 4-bis-(4-aminophenyl)-piperazine, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl, 4, 4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-(phenylenediisopropylidene) 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)]dianiline, 4,4′-diaminobenzanilide, 4,4′-diaminostilbenzene, 1,4-bis(4-aminophenyl)-piperazine and other main-chain diamines:
dodecanoxy-2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecanoxy-2,4-diaminobenzene, octadecanoxy-2,4-diaminobenzene, pentadecanoxy-2,5-diaminobenzene, octadecanoxy-2,5 -diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, 3, Cholestanyl 5-diaminobenzoate, Cholestenyl 3,5-diaminobenzoate, Lanostanyl 3,5-diaminobenzoate, 3,6-bis(4-aminobenzoyloxy)cholestane, 3,6-bis(4-aminophenoxy) Cholestan, 4-(4′-trifluoromethoxybenzoyloxy)cyclohexyl-3,5-diaminobenzoate, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane, 3,5 -Diaminobenzoic acid = 5ξ-cholestan-3-yl, the following formula (E-1)

(In formula (E-1), X ^I and X ^II are each independently a single bond, -O-, *-COO- or *-OCO- (wherein "*" is a bond with X ^I ), R ^I is an alkanediyl group having 1 to 3 carbon atoms, R ^II is a single bond or an alkanediyl group having 1 to 3 carbon atoms, and R ^III is an alkanediyl group having 1 to 3 carbon atoms. 20 alkyl, alkoxy, fluoroalkyl or fluoroalkoxy groups, a is 0 or 1, b is an integer of 0 to 3, c is an integer of 0 to 2, d is 0 or 1, provided that 1≤a+b+c≤3.)
A side chain type diamine such as a compound represented by;
As the diaminoorganosiloxane, for example, 1,3-bis(3-aminopropyl)-tetramethyldisiloxane and the like can be mentioned; and diamines described in JP-A-2010-97188 can be used. When synthesizing the polyamic acid [P], the diamines may be used singly or in combination of two or more.

- Synthesis of polyamic acid Polyamic acid [P] can be obtained by reacting the above tetracarboxylic dianhydride and diamine together with a molecular weight modifier, if necessary. The ratio of the tetracarboxylic dianhydride and the diamine to be used in the synthetic reaction of the polyamic acid [P] is such that the acid anhydride group of the tetracarboxylic dianhydride is 0.00 to 1 equivalent of the amino group of the diamine. A ratio of 2 to 2 equivalents is preferred. Molecular weight modifiers include, for example, acid monoanhydrides such as maleic anhydride, phthalic anhydride and itaconic anhydride; monoamine compounds such as aniline, cyclohexylamine and n-butylamine; and monoisocyanate compounds such as phenyl isocyanate and naphthyl isocyanate. is mentioned. The proportion of the molecular weight modifier used is preferably 20 parts by mass or less with respect to a total of 100 parts by mass of the tetracarboxylic dianhydride and diamine used.

The synthesis reaction of polyamic acid [P] is preferably carried out in an organic solvent. At this time, the reaction temperature is preferably −20° C. to 150° C., and the reaction time is preferably 0.1 to 24 hours. Organic solvents used in the reaction include, for example, aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. Particularly preferred organic solvents are N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide, m-cresol and xylenol. and halogenated phenols, or a mixture of one or more of these with other organic solvents (e.g., butyl cellosolve, diethylene glycol diethyl ether, etc.). The amount (a) of the organic solvent used is such that the total amount (b) of the tetracarboxylic dianhydride and the diamine is 0.1 to 50% by mass with respect to the total amount (a+b) of the reaction solution. is preferred.

As described above, a reaction solution in which the polyamic acid [P] is dissolved is obtained. This reaction solution may be used for the preparation of the liquid crystal aligning agent as it is, or may be used for the preparation of the liquid crystal aligning agent after isolating the polyamic acid [P] contained in the reaction solution.

(polyamic acid ester)
When the polymer [P] is a polyamic acid ester, the polyamic acid ester can be obtained by, for example, [I] a method of reacting the polyamic acid [P] obtained by the above synthesis reaction with an esterifying agent, [II] tetra It can be obtained by a method of reacting a carboxylic acid diester with a diamine containing a specific diamine, a method of reacting a [III] tetracarboxylic acid diester dihalide with a diamine containing a specific diamine, and the like. The polyamic acid ester contained in the liquid crystal aligning agent may have only an amic acid ester structure, or may be a partially esterified product in which an amic acid structure and an amic acid ester structure coexist. The reaction solution obtained by dissolving the polyamic acid ester may be used for the preparation of the liquid crystal aligning agent as it is, or the polyamic acid ester contained in the reaction solution may be isolated and used for the preparation of the liquid crystal aligning agent.

(polyimide)
When the polymer [P] is a polyimide, the polyimide can be obtained, for example, by dehydrating and ring-closing the polyamic acid [P] synthesized as described above to imidize it. The polyimide may be a complete imidized product obtained by dehydrating and ring-closing all the amic acid structures that the precursor polyamic acid [P] had, and only a part of the amic acid structure is dehydrated and ring-closed to form the amic acid. It may be a partially imidized product in which the structure and the imide ring structure coexist. The polyimide used for preparing the liquid crystal aligning agent preferably has an imidization rate of 20 to 99%, more preferably 30 to 90%. The imidization rate is expressed as a percentage of the ratio of the number of imide ring structures to the sum of the number of amic acid structures and the number of imide ring structures of the polyimide. Here, part of the imide ring may be an isoimide ring.

The dehydration and ring closure of the polyamic acid [P] is preferably carried out by dissolving the polyamic acid [P] in an organic solvent, adding a dehydrating agent and a dehydration and ring closure catalyst to the solution, and heating if necessary. In this method, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent used is preferably 0.01 to 20 mol per 1 mol of the amic acid structure of the polyamic acid [P]. As the dehydration ring-closing catalyst, for example, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used. The amount of the dehydration ring-closing catalyst used is preferably 0.01 to 10 mol per 1 mol of the dehydrating agent used. Examples of the organic solvent used in the dehydration ring-closure reaction include the organic solvents exemplified as those used in the synthesis of the polyamic acid. The reaction temperature for the dehydration ring closure reaction is preferably 0 to 180°C. The reaction time is preferably 1.0 to 120 hours. The reaction solution containing the polyimide obtained by the above reaction may be used for the preparation of the liquid crystal aligning agent as it is, or may be used for the preparation of the liquid crystal aligning agent after isolating the polyimide. Polyimides can also be obtained by imidization of polyamic acid esters.

The solution viscosity of the polyamic acid, polyamic acid ester and polyimide to be contained in the liquid crystal aligning agent is preferably 10 to 800 mPa s when the concentration is 10% by mass, and is preferably 15 to 500 mPa s. More preferably, it has a solution viscosity of s. Incidentally, the solution viscosity (mPa s) is the E-type rotational It is a value measured at 25°C using a viscometer.

The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) of polyamic acid, polyamic acid ester and polyimide is preferably 1,000 to 500,000, more preferably 5,000 to 100,000. The molecular weight distribution (Mw/Mn) represented by the ratio of Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is preferably 15 or less, more preferably 10 or less.

(Polyorganosiloxane)
When the polymer [P] is a polyorganosiloxane, the polyorganosiloxane (hereinafter also referred to as "polysiloxane [P]") has a partial structure represented by the above formula (1), so long as the structure and The manufacturing method is not particularly limited. Polysiloxane [P] can be obtained, for example, by a hydrolysis/condensation reaction of a hydrolyzable silane compound. Specifically, the following methods [1] and [2] are mentioned.

[1] Synthesizing an epoxy group-containing polyorganosiloxane by hydrolytic condensation of a hydrolyzable silane compound (ms-1) having an epoxy group, or a mixture of the silane compound (ms-1) and another silane compound. Then, a method of reacting the obtained epoxy group-containing polyorganosiloxane with a carboxylic acid having a partial structure represented by the above formula (1) (hereinafter also referred to as "specific carboxylic acid").
[2] A method of hydrolytically condensing a hydrolyzable silane compound (ms-2) having a partial structure represented by the above formula (1), or a mixture of the silane compound (ms-2) and another silane compound. .
Among these, the method [1] is preferable because it is simple and can increase the introduction rate of the partial structure represented by the above formula (1) in the polysiloxane [P].

Specific examples of the silane compound (ms-1) include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropyl. methyldiethoxysilane, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethylmethyldimethoxysilane, 2-glycidoxyethyldimethylmethoxysilane, 2-glycidoxyethyldimethylethoxysilane, 4-glycidoxysilane Butyltrimethoxysilane, 4-glycidoxybutylmethyldimethoxysilane, 4-glycidoxybutylmethyldiethoxysilane, 4-glycidoxybutyldimethylmethoxysilane, 4-glycidoxybutyldimethylethoxysilane, 2-(3 ,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-(3,4-epoxycyclohexyl)propyltrimethoxysilane and the like. As the silane compound (ms-1), one of these can be used alone or two or more of them can be used in combination.

Other silane compounds used for synthesizing the epoxy group-containing polyorganosiloxane are not particularly limited as long as they are hydrolyzable silane compounds. Specific examples thereof include alkoxysilanes such as tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, and dimethyldiethoxysilane;
3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-(3 - Nitrogen/sulfur atom-containing alkoxysilanes such as cyclohexylamino)propyltrimethoxysilane and N-2-(aminoethyl)-3-aminopropyltrimethoxysilane;
3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropyltriethoxysilane, 6-(meth)acryloyloxyhexyltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3- (Meth)acryloxypropylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, p-styryltrimethoxysilane, and other unsaturated hydrocarbon-containing alkoxysilanes; trimethoxysilylpropylsuccinic anhydride, etc. is mentioned. Other silane compounds can be used singly or in combination of two or more. In addition, in this specification, "(meth)acryloxy" is meant to include "acryloxy" and "methacryloxy".

The hydrolysis/condensation reaction of the silane compound can be carried out by reacting one or more of the above silane compounds with water, preferably in the presence of a suitable catalyst and organic solvent. In the reaction, the ratio of water used is preferably 1 to 30 mol per 1 mol of the silane compound (total amount). Examples of the catalyst to be used include acids, alkali metal compounds, organic bases, titanium compounds, zirconium compounds and the like. The amount of the catalyst used varies depending on the type of catalyst, reaction conditions such as temperature, etc., and should be appropriately set. be. Examples of organic solvents to be used include hydrocarbons, ketones, esters, ethers, alcohols and the like. Among these, it is preferable to use a water-insoluble or poorly water-soluble organic solvent. The ratio of the organic solvent to be used is preferably 10 to 10,000 parts by mass with respect to 100 parts by mass of the silane compounds used in the reaction.

The above hydrolysis/condensation reaction is preferably carried out by heating, for example, in an oil bath. At that time, the heating temperature is preferably 130° C. or lower, and the heating time is preferably 0.5 to 12 hours. After completion of the reaction, the desired polyorganosiloxane can be obtained by drying the organic solvent layer separated from the reaction solution with a desiccant, if necessary, and then removing the solvent. The method for synthesizing the polyorganosiloxane is not limited to the hydrolysis/condensation reaction described above, and may be carried out, for example, by reacting a hydrolyzable silane compound in the presence of oxalic acid and alcohol.

In the above method [1], the epoxy group-containing polyorganosiloxane obtained by the above reaction is then reacted with a specific carboxylic acid. As a result, the epoxy group of the epoxy group-containing polyorganosiloxane reacts with the carboxyl group of the specific carboxylic acid to form polysiloxane [P] having the partial structure represented by the above formula (1) in the side chain. Obtainable.

Specific examples of the specific carboxylic acid include compounds represented by the following formulas (3-1) to (3-12).

The content of the partial structure represented by the above formula (1) in one molecule of polysiloxane [P] is preferably 5 mol% or more with respect to the silicon atoms possessed by polysiloxane [P], and 10 More preferably 15 mol % or more, more preferably 15 mol % or more. In addition, the content of the partial structure represented by the above formula (1) in one molecule of polysiloxane [P] is preferably 70 mol% or less with respect to the silicon atoms possessed by polysiloxane [P]. , is more preferably 60 mol % or less, and even more preferably 50 mol % or less.

In the synthesis of polysiloxane [P], the carboxylic acid used for the reaction with the epoxy group-containing polyorganosiloxane may be only the specific carboxylic acid, but other carboxylic acids other than the specific carboxylic acid may be used in combination. good too. The other carboxylic acid may be any carboxylic acid that does not have the partial structure represented by the above formula (1), and various carboxylic acids can be used.

The reaction between the epoxy group-containing polyorganosiloxane and the carboxylic acid can be preferably carried out in the presence of a catalyst and an organic solvent. As the catalyst to be used, for example, compounds known as so-called curing accelerators that promote the reaction of organic bases and epoxy compounds (eg, tertiary organic amines, quaternary organic amines, quaternary ammonium salts, etc.) can be used. The amount of the catalyst used is preferably 100 parts by mass or less, more preferably 0.1 to 20 parts by mass, per 100 parts by mass of the epoxy group-containing polyorganosiloxane.

Examples of organic solvents used in the above reaction include hydrocarbons, ethers, esters, ketones, amides, alcohols and the like. The organic solvent is preferably used in such a proportion that the solid content concentration (the ratio of the total weight of components other than the solvent in the reaction solution to the total weight of the solution) is 0.1% by mass or more. It is more preferable to use it in a proportion of up to 50% by mass. In the above reaction, the reaction temperature is preferably 0 to 200°C, more preferably 50 to 150°C. The reaction time is preferably 0.1 to 50 hours, more preferably 0.5 to 20 hours. After completion of the reaction, it is preferable to wash the organic solvent layer separated from the reaction solution with water. After washing with water, the organic solvent layer is dried with a suitable desiccant if necessary, and then the solvent is removed to obtain the target polysiloxane [P].

Polysiloxane [P] preferably has a solution viscosity of 1 to 500 mPa s, more preferably 3 to 200 mPa s, when it is made into a solution having a concentration of 10% by mass. is more preferable. For polysiloxane [P], the polystyrene equivalent weight average molecular weight (Mw) measured by GPC is preferably 1,000 to 200,000, more preferably 2,000 to 50,000, and 3 ,000 to 20,000.

(Addition polymer)
When the polymer [P] is an addition polymer, the addition polymer (hereinafter also referred to as “addition polymer [P]”) has a partial structure represented by the above formula (1) and is polymerized The structure and production method are not particularly limited as long as the polymer has a structural unit derived from a monomer having a carbon-carbon unsaturated bond. The addition polymer [P] is, for example, an unsaturated monomer (ma-1) having a partial structure represented by the above formula (1), or an unsaturated monomer (ma-1) and other unsaturated It can be obtained by polymerizing a mixture with a monomer.

Any monomer having a polymerizable carbon-carbon unsaturated bond can be used as the unsaturated monomer. Examples of the monomer include compounds having a (meth)acryloyl group, vinyl group, vinylphenyl group, maleimide group, and the like. The unsaturated polymer [P] includes poly(meth)acrylate, maleimide-based polymer, styrene-maleimide-based copolymer, and poly(meth)acrylamide, in that a liquid crystal alignment film having excellent liquid crystal alignment can be formed. At least one selected from the group consisting of can be preferably used.

（式（４－２）～式（４－１２）中、Ｒは水素原子又はメチル基である。） The unsaturated monomer (ma-1) is not particularly limited as long as it has the partial structure represented by the above formula (1). Specific examples of the unsaturated monomer (ma-1) include compounds represented by the following formulas (4-1) to (4-12).

(In formulas (4-2) to (4-12), R is a hydrogen atom or a methyl group.)

Specific examples of other unsaturated monomers include unsaturated carboxylic acids such as (meth)acrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, and vinylbenzoic acid; alkyl (meth)acrylates (e.g., methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc.), cycloalkyl (meth) acrylate, benzyl (meth) acrylate, trimethoxysilylpropyl (meth) acrylate, (meth) acrylic acid 2 -hydroxyethyl, glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, 3,4-epoxybutyl (meth)acrylate, and 4-hydroxybutyl glycidyl ether (meth)acrylate, etc. Unsaturated carboxylic acid esters: Unsaturated polyvalent carboxylic anhydrides such as maleic anhydride: (meth)acrylic compounds such as;
Aromatic vinyl compounds such as styrene, methylstyrene, divinylbenzene, 4-hydroxystyrene, 4-vinylbenzoic acid and 4-(glycidyloxymethyl)styrene; 1,3-butadiene and 2-methyl-1,3-butadiene, etc. a conjugated diene compound of;
N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, 4-(2,5-dioxo-3-pyrrolin-1-yl)benzoic acid, N-(4-glycidyloxyphenyl)maleimide, N-glycidylmaleimide , 3-maleimidobenzoic acid, 3-maleimidopropionic acid, 3-(2,5-dioxo-3-pyrrolin-1-yl)benzoic acid, and 4-(2,5-dioxo-3-pyrrolin-1-yl ) maleimide compounds such as methyl benzoate. In synthesizing the addition polymer [P], other unsaturated monomers may be used singly or in combination of two or more.

The content ratio of the partial structure represented by the above formula (1) in one molecule of the addition polymer [P] is 2 mol% or more with respect to the total structural units of the addition polymer [P]. It is preferably 5 mol % or more, more preferably 10 mol % or more. Further, the content ratio of the partial structure represented by the above formula (1) in one molecule of the addition polymer [P] is 60 mol% or less with respect to the total structural units of the addition polymer [P]. preferably 50 mol % or less.

The addition polymer [P] can be obtained, for example, by polymerizing monomers in the presence of a polymerization initiator. Polymerization initiators to be used include, for example, 2,2′-azobis(isobutyronitrile), 2,2′-azobis(2,4-dimethylvaleronitrile), 2,2′-azobis(4-methoxy-2 , 4-dimethylvaleronitrile) are preferred. The proportion of the polymerization initiator used is preferably 0.01 to 30 parts by mass with respect to 100 parts by mass of all monomers used in the reaction.

The above polymerization reaction is preferably carried out in an organic solvent. Examples of the organic solvent used for the reaction include alcohols, ethers, ketones, amides, esters, hydrocarbon compounds, etc. Diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether acetate and the like are preferred. The reaction temperature is preferably 30° C. to 120° C., and the reaction time is preferably 1 to 36 hours. The amount (a) of the organic solvent used is such that the total amount (b) of the monomers used in the reaction is 0.1 to 60% by mass with respect to the total amount (a+b) of the reaction solution. is preferred.

The polystyrene equivalent weight average molecular weight (Mw) measured by GPC of the addition polymer [P] is preferably 250 to 500,000, more preferably 500 to 100,000.

The method for producing the addition polymer [P] is not limited to the above. For example, after polymerizing a monomer containing an unsaturated monomer (m-1) having an epoxy group in the presence of a polymerization initiator, , can also be obtained by a method of reacting the resulting polymer with a specific carboxylic acid.

From the viewpoint of obtaining a liquid crystal alignment film with high mechanical strength, the content of the polymer [P] in the liquid crystal alignment agent is based on a total of 100 parts by mass of the solid components (that is, components other than the solvent) in the liquid crystal alignment agent. , preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and still more preferably 20% by mass or more.

<Other ingredients>
The liquid crystal aligning agent of the present disclosure may further contain components other than the polymer [P] (hereinafter also referred to as "other components"), if necessary. The other component is a component that does not have the partial structure represented by the above formula (1), and examples thereof include the following compound [A], polymer [Q], compound [B], solvent, and the like.

(Compound [A])
Compound [A] is a compound having two or more groups capable of forming a bond with group X ¹ in the above formula (1) (excluding polymers, hereinafter also referred to as "compound (A1)"), or It is a compound (hereinafter also referred to as "compound (A2)") having two or more groups capable of forming a clathrate by interacting with group ^X1 in the above formula (1). Among these, compound (A1) is a low-molecular-weight compound, and compound (A2) may be a low-molecular-weight compound or a polymer. The term "low-molecular-weight compound" as used herein refers to a compound having no molecular weight distribution, and is distinguished from a "polymer" having repeating units derived from monomers. By blending the compound [A] together with the polymer [P] in the liquid crystal aligning agent of the present disclosure, it is preferable in that a film having higher adhesion and film strength can be formed.

In the embodiment in which the liquid crystal aligning agent contains the compound [A] together with the polymer [P], when the polymer [P] has a group J ¹ (that is, when m in formula (1) is 1), the compound [A ] has, as the group Y ¹ , two or more groups capable of forming a bond with the group X ¹ of the polymer [P]. In this case, compound [A] (that is, compound (A1)) functions as a cross-linking agent by being mixed together with polymer [P]. As the compound (A1), the mobility of the compound (A1) is increased to allow the crosslinking reaction between the polymer [P] and the compound (A1) to proceed rapidly, thereby increasing the effect of improving the film strength. A low-molecular-weight compound having a molecular weight of 1,000 or less can be preferably used. The number of groups Y ¹ possessed by the compound (A1) is preferably 2-10, more preferably 2-6.

The compound (A1) can be selected depending on the group ^X1 possessed by the polymer [P]. Specific examples of the compound (A1) include, for example, compounds represented by the following formula.

In the embodiment in which the liquid crystal aligning agent contains the compound [A] together with the polymer [P], the polymer [P] forms a clathrate by interaction with the compound [A], and the clathrate is separated by stimulation. (i.e., m in formula (1) is 0), the compound [A] has two groups capable of interacting with the group X ¹ of the polymer [P] as the group Y ¹ have more than In this case, the compound [A] (that is, the compound (A2)) is preferably a polymer having a group ^Y1 in a side chain in order to increase the effect of improving the mechanical strength of the film.

When the compound (A2) is a polymer, its main chain is not particularly limited, but should be at least one selected from the group consisting of polyamic acids, polyamic acid esters, polyimides, polyorganosiloxanes, and addition polymers. is preferred, and at least one selected from the group consisting of polyorganosiloxanes and addition polymers is more preferred from the viewpoint of ease of synthesizing a polymer having a group ^Y1 in its side chain.

In the liquid crystal aligning agent of the present disclosure, the content of the compound [A] is, from the viewpoint of sufficiently obtaining the effect of improving the mechanical strength of the film, relative to the total amount of 100 parts by mass of the polymer [P] contained in the liquid crystal aligning agent. , 0.1 parts by mass or more. The content of the compound [A] is more preferably 0.5 parts by mass or more, still more preferably 1 part by mass or more, and even more preferably 2 parts by mass or more with respect to 100 parts by mass of the total amount of the polymer components. In addition, from the viewpoint of suppressing a decrease in the toughness of the film, the content of the compound [A] is preferably 35 parts by mass or less, more preferably 30 parts by mass or less, with respect to 100 parts by mass of the total amount of the polymer [P]. , more preferably 20 parts by mass or less. As the compound [A], one type may be used alone, or two or more types may be used in combination.

(Polymer [Q])
Polymer [Q] is a polymer that does not have the partial structure represented by the above formula (1). By including the polymer [Q] together with the polymer [P] in the liquid crystal aligning agent of the present disclosure, it is possible to further improve the mechanical strength of the film. The polymer [Q] is preferably at least one selected from the group consisting of polyamic acids, polyamic acid esters, polyimides and addition polymers. Specific examples of the polyamic acid, polyamic acid ester and polyimide as the polymer [Q] include polymers obtained by reacting the above-described tetracarboxylic dianhydride with other diamines. The addition polymer as the polymer [Q] is a polymer obtained using one or more monomers having a (meth)acryloyl group, vinyl group, vinylphenyl group or maleimide group. At least one selected from the group consisting of poly(meth)acrylates, maleimide-based polymers and styrene-maleimide-based copolymers is preferred. Among these, the polymer [Q] is particularly preferably at least one selected from the group consisting of polyamic acids, polyamic acid esters and polyimides.

In addition, according to the blend system of the polymer [P] and the polymer [Q], phase separation between the polymer [P] and the polymer [Q] is likely to occur in the liquid crystal alignment film. It is thought that coalescence can be easily unevenly distributed in the upper layer.

When the polymer [Q] is contained in the liquid crystal aligning agent, the content of the polymer [Q] in the liquid crystal aligning agent is 1 part by mass of the polymer [P] per 100 parts by mass of the polymer [Q]. The amount is preferably 5 parts by mass or more, more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more. The content of polymer [Q] is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, per 100 parts by mass of polymer [Q]. In preparation of the liquid crystal aligning agent, as the polymer [Q], one type may be used alone, or two or more types may be used in combination.

The total content of the polymer [P] and the polymer [Q] in the liquid crystal aligning agent is the total mass of solids contained in the liquid crystal aligning agent (liquid crystal It is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, relative to the total mass of components other than the solvent of the alignment agent).

(Compound [B])
Compound [B] is a compound capable of reacting with the residue of group ^J1 cleaved upon stimulation. By including such a compound [B] in the liquid crystal aligning agent, it is possible to suppress the recombination of residues cleaved by stimulation.

（式中、ｋは７～３０の整数である。） The compound [B] is a monofunctional compound capable of suppressing the reverse reaction of the reaction that progresses due to a stimulus when J ¹ in the above formula (1) is based on an equilibrium reaction (reversible reaction), in other words, a stimulus A monofunctional compound is used which is more reactive with the residues of the group ^J1 cleaved by. For example, J ¹ is an unsaturated 6-membered ring structure formed by an addition reaction between a conjugated diene and an alkene (for example, unsaturated 6-membered ring structure), the compound [B] can be preferably used in order to suppress recombination due to the Diels-Alder reaction after cleavage by application of a stimulus. Specific examples of the compound [B] in the case where J ¹ is a group having an unsaturated 6-membered ring structure formed by an addition reaction of a conjugated diene and an alkene include compounds having an anthracene structure. includes, for example, compounds represented by the following formulas.

(Wherein, k is an integer from 7 to 30.)

Further, when J ¹ is a group having a (thio)urea structure (for example, the urea structure in the above formula (1-2-13)), the compound [ A monoamine compound can be preferably used as B].

When the compound [B] is contained in the liquid crystal aligning agent, the content of the compound [B] in the liquid crystal aligning agent is preferably 1 part by mass or more with respect to 100 parts by mass of the polymer [P]. It is more preferable to set it as part by mass or more. In addition, the content of the compound [B] is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and 10 parts by mass or less with respect to 100 parts by mass of the polymer [P]. is more preferred. In preparation of a liquid crystal aligning agent, as compound [B], one type may be used alone, or two or more types may be used in combination.

Components other than the solvent that are blended as other components include, in addition to the above, functional silane compounds (e.g., 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, etc.), antioxidants, metal chelate compounds, curing accelerators, surfactants, fillers, dispersants, photosensitizers and the like. The content of these compounds can be appropriately selected according to each compound within a range that does not impair the effects of the present disclosure.

(solvent)
The liquid crystal aligning agent of the present disclosure is preferably prepared as a liquid composition in which the polymer [P] and optionally blended components are dissolved in a solvent. The solvent is preferably an organic solvent, and examples thereof include aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons.

Specific examples of organic solvents used include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,2-dimethyl-2-imidazolidinone, 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, methylmethoxypropionate, ethylethoxypropionate Onete, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl 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, diisopentyl ether, ethylene carbonate, propylene carbonate , cyclohexanone, diisobutyl ketone, 3-methoxy-1-butanol, and the like. These can be used individually or in mixture of 2 or more types.

The solid content concentration in the liquid crystal aligning agent (ratio of the total mass of components other than the solvent of the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., but preferably It is in the range of 1 to 10% by mass. When the solid content concentration is 1% by mass or more, there is a tendency that the film thickness of the coating film can be sufficiently secured and a good liquid crystal alignment film can be obtained. Moreover, when the solid content concentration is 10% by mass or less, the film thickness of the coating film does not become excessively large, and the viscosity of the liquid crystal aligning agent can be increased appropriately, and there is a tendency that the coatability can be improved.

≪Liquid crystal alignment film≫
The liquid crystal alignment film of the present disclosure is an alignment film formed from the liquid crystal alignment agent prepared as described above. The liquid crystal alignment film of the present disclosure is prepared by the following steps 1 to 3:
Step 1: a step of applying a liquid crystal aligning agent containing a polymer [P] onto a substrate;
Step 2: Step of cross-linking the polymer contained in the liquid crystal aligning agent on the substrate, and Step 3: Step of cutting the bond or interaction between the polymers by applying a stimulus to the cross-linked polymer.
It is preferable to manufacture by a method comprising

<Step 1: Coating step>
First, a liquid crystal aligning agent is applied onto a substrate, and preferably the coated surface is heated to form a coating film on the substrate. Examples of the substrate include glass such as float glass and soda glass; and transparent substrates made of resin such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly(alicyclic olefin). Application of the liquid crystal aligning agent to the substrate is preferably performed by an offset printing method, a flexographic printing method, a spin coating method, a roll coater method, or an inkjet printing method.

After applying the liquid crystal aligning agent, preheating (pre-baking) is preferably carried out for the purpose of preventing dripping of the applied liquid crystal aligning agent. The pre-baking temperature is preferably 30-200° C., and the pre-baking time is preferably 0.25-10 minutes.

<Step 2: Crosslinking step>
Subsequently, the polymer contained in the liquid crystal alignment film coated on the substrate is crosslinked. The cross-linking reaction may be performed by heat during pre-baking. Alternatively, baking (post-baking) may be performed following pre-baking to remove the solvent in the coating film and advance the cross-linking reaction. These embodiments are preferable in that the removal of the solvent and the cross-linking reaction can be performed in one step, and the simplification of the production process can be achieved. The baking temperature (post-baking temperature) at this time is preferably 80 to 280.degree. C., more preferably 100 to 250.degree. The post-bake time is preferably 5-200 minutes. The thickness of the film thus formed is preferably 0.001 to 1 μm. Alternatively, a separate heat treatment may be performed between pre-baking and post-baking to advance the cross-linking reaction.

<Step 3: Cutting step>
After cross-linking the polymer, a stimulus is applied to the cross-linked polymer to cause a cleavage reaction at the ^J1 site in the above formula (1) or separate the clathrate formed by the cross-linking step. Processing (disconnection processing) is performed. Cleavage treatment can be performed by a method depending on the stimulus applied to cut the bond or interaction between polymers formed by the cross-linking step. For example, if the stimulus for the cleavage treatment is heat, it is preferable to remove the solvent in the coating and post-bake for the crosslinking reaction to break the bonds or interactions between the polymers formed by the crosslinking step. . In this case, the three treatments of the heat treatment for removing the solvent, the treatment for the cross-linking reaction of the polymer, and the cutting treatment between the polymers can be performed in one step, which simplifies the manufacturing process. It is preferable in that it can be planned. Such a cutting treatment can be carried out by designing the cleavage temperature or separation temperature for cutting bonds or interactions between polymers to be higher than the cross-linking temperature.

In addition, when the stimulus for the cutting process is light, from the viewpoint of simplifying the process, light irradiation treatment for curing the sealant and light irradiation treatment for the optical alignment treatment are used. It is preferable to carry out a treatment for breaking bonds or interactions between polymers formed by the cross-linking step. It should be noted that the stimulus for the cutting process may be applied separately from the post-baking process, the seal hardening process, and the photo-alignment process.

≪Liquid crystal element≫
The liquid crystal element of the present disclosure includes a liquid crystal alignment film formed using the liquid crystal alignment agent described above. The operation mode of the liquid crystal in the liquid crystal element is not particularly limited. Field Switching) type, OCB (Optically Compensated Bend) type, PSA type (Polymer Sustained Alignment) type, and the like.

The liquid crystal element of the present disclosure can be manufactured by a method including the above-described coating step and liquid crystal cell construction step, and optionally including an orientation treatment step. It should be noted that the substrate used in the coating process differs depending on the desired operation mode. The alignment treatment process and the liquid crystal cell construction process are common to each operation mode.

Regarding the substrates used, two substrates provided with patterned electrodes are used when manufacturing a TN-type, STN-type or VA-type liquid crystal element. On the other hand, when manufacturing an IPS-type or FFS-type liquid crystal element, a substrate provided with electrodes patterned in a comb shape and a counter substrate provided with no electrodes are used. As the electrode, a transparent conductive film such as an NESA film (registered trademark of PPG, USA) made of tin oxide (SnO ₂ ) or an ITO film made of indium oxide-tin oxide (In ₂ O ₃ —SnO ₂ ) can be used. .

<Orientation treatment step>
When manufacturing a TN-type, STN-type, IPS-type, or FFS-type liquid crystal element, a treatment (orientation treatment) for imparting liquid crystal alignment ability to the formed coating film is performed. As a result, the coating film is provided with the ability to align liquid crystal molecules to form a liquid crystal alignment film. Orientation treatment includes a rubbing treatment in which the coating film formed on the substrate is rubbed in a certain direction with a roll wrapped with a cloth made of fibers such as nylon, rayon, cotton, etc., and a coating film formed on the substrate that is irradiated with light. A photo-alignment treatment or the like can be used for imparting liquid crystal alignment ability to the coating film. On the other hand, when manufacturing a vertically aligned (VA) type liquid crystal element, the coating film formed in the above step 1 can be used as a liquid crystal alignment film as it is. Orientation treatment may be applied to the film. A liquid crystal alignment film suitable for a vertically aligned liquid crystal element is also suitable for a PSA type liquid crystal element.

In the photo-alignment treatment, ultraviolet rays and visible rays including light having a wavelength of 150 to 800 nm can be used as the radiation to irradiate the coating film. Ultraviolet rays including light with a wavelength of 200 to 400 nm are preferred. When the radiation is polarized, it may be linearly polarized or partially polarized. When the radiation used is linearly polarized or partially polarized, irradiation may be performed in a direction perpendicular to the substrate surface, obliquely, or a combination thereof. In the case of non-polarized radiation, the irradiation direction is oblique.

Examples of light sources to be used include low pressure mercury lamps, high pressure mercury lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps and excimer lasers. The dose of radiation to the substrate surface is preferably 400 to 50,000 J/m ² , more preferably 1,000 to 20,000 J/m ² . After light irradiation for imparting alignment ability, the substrate surface is treated with, for example, water, an organic solvent (eg, methanol, isopropyl alcohol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, etc.), or a mixture thereof. A cleaning treatment or a substrate heating treatment may be performed.

<Cell construction process>
In this step, two substrates on which a liquid crystal alignment film is formed are prepared, and a liquid crystal cell is manufactured so that the liquid crystal is arranged between the two substrates adjacent to the liquid crystal alignment film. In order to manufacture a liquid crystal cell, for example, two substrates are arranged facing each other with a gap so that the liquid crystal alignment films face each other, and a sealant is applied to the outer peripheral edge of at least one of the two substrates. After that, a method of bonding two substrates together by irradiating an area containing a sealant with ultraviolet rays, and then injecting liquid crystal into a cell gap surrounded by the surface of the substrate and the sealant to seal the injection hole; A method using the ODF method and the like can be mentioned.

As the sealing agent, for example, an epoxy resin or the like containing a curing agent and aluminum oxide spheres as spacers can be used. Liquid crystals include nematic liquid crystals and smectic liquid crystals, among which nematic liquid crystals are preferred. In the PSA mode, 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 the pair of substrates.

Subsequently, for each mode liquid crystal cell, a polarizing plate is adhered to the outer surface of the liquid crystal cell, if necessary, to form a liquid crystal element. Examples of the polarizing plate include a polarizing plate in which a polarizing film called "H film" in which iodine is absorbed while stretching orientation of polyvinyl alcohol is sandwiched between cellulose acetate protective films, or a polarizing plate composed of the H film itself.

The liquid crystal device of the present disclosure can be effectively applied to various uses. Specifically, for example, various display devices such as watches, portable game machines, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, various monitors, liquid crystal televisions, information displays, etc. , a light control film, a retardation film, and the like.

The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

In the following examples, the solution viscosity, weight average molecular weight (Mw), number average molecular weight (Mn) and imidization rate of the polymer were measured by the following methods.
<Polymer Solution Viscosity>
The solution viscosity of the polymer was measured at 25°C using an E-type viscometer.
<Weight average molecular weight (Mw) and number average molecular weight (Mn)>
Mw and Mn were measured by gel permeation chromatography (GPC) under the following conditions. Molecular weight distribution (Mw/Mn) was calculated from the obtained Mw and Mn.
Apparatus: "GPC-101" of Showa Denko K.K.
GPC column: Shimadzu GLC Co., Ltd. "GPC-KF-801", "GPC-KF-802", "GPC-KF-803" and "GPC-KF-804" combined Mobile phase: tetrahydrofuran (THF )
Column temperature: 40°C
Flow rate: 1.0 mL/min Sample concentration: 1.0% by mass
Sample injection volume: 100 μL
Detector: Differential refractometer Standard substance: Monodisperse polystyrene <Imidation rate of polyimide>
The polyimide solution was poured into pure water, and the resulting precipitate was thoroughly dried under reduced pressure at room temperature, dissolved in deuterated dimethylsulfoxide, and subjected to ¹ H-NMR measurement at room temperature using tetramethylsilane as a reference substance. . From the obtained ¹ H-NMR spectrum, the imidization rate [%] was determined by the following formula (1).
Imidation rate [%]=(1−(β ¹ /(β ² ×α)))×100 (1)
(In formula (1), β ¹ is the peak area derived from protons of the NH group appearing near the chemical shift of 10 ppm, β ² is the peak area derived from other protons, and α is the precursor of the polymer (polyamic acid ) is the number ratio of other protons to one proton of the NH group.)

The abbreviations of the compounds used in the examples below are shown below. In the following, for convenience, "the compound represented by formula (X)" may be simply referred to as "compound (X)".

<Synthesis of polymer>
1. Synthesis of Polyamic Acid [Synthesis Example 1-1]
100 mol parts of 2,3,5-tricarboxycyclopentylacetic dianhydride as a tetracarboxylic dianhydride, and 30 mol parts of 4,4′-diaminodiphenyl ether as a diamine, cholestanyloxy-2,4-diaminobenzene 20 mol parts, and 50 mol parts of the compound (DA-4) were dissolved in N-methyl-2-pyrrolidone (NMP) and reacted at 60° C. for 4 hours to give polyamic acid (the polymer (PAA-1) A solution containing 20% by mass of ) was obtained. A small amount of this solution was taken and measured to have a solution viscosity of 570 mPa·s.

[Synthesis Examples 1-2 to 1-9]
Polymerization was carried out in the same manner as in Synthesis Example 1-1 except that the types and amounts of the tetracarboxylic dianhydride and diamine used in the polymerization were changed as shown in Table 1 to obtain a polyamic acid polymer (PAA-2 ) to (PAA-9) were obtained. In addition, the polymerization is performed so that the viscosity of the NMP solution with a polymer concentration of 10% by mass is 80 to 100 mPa s, and the molar ratio of the diamine and the tetracarboxylic dianhydride (diamine/tetracarboxylic dianhydride) is adjusted. It was carried out to 0.95-1.00. In Table 1, the numerical value of the acid anhydride represents the ratio (parts by moles) of each compound to 100 parts by moles of the total amount of tetracarboxylic dianhydride used in the synthesis. The numerical value of the diamine represents the ratio (mol parts) of each compound to 100 mol parts of the total amount of diamines used in the synthesis.

2. Synthesis of Polyimide [Synthesis Example 1-10]
100 mol parts of 2,3,5-tricarboxycyclopentylacetic dianhydride as a tetracarboxylic dianhydride, and 35 mol parts of 4,4′-diaminodiphenyl ether as a diamine, cholestanyloxy-2,4-diaminobenzene 5 mol parts and 60 mol parts of compound (DA-10) were dissolved in NMP and reacted at 60° C. for 4 hours to obtain a solution containing 20% by mass of polyamic acid. Next, NMP was added to the resulting polyamic acid solution, and pyridine and acetic anhydride were added in 3 molar equivalents relative to the carboxyl groups of the polyamic acid to carry out dehydration ring closure reaction at 80° C. for 4 hours. After the dehydration ring-closure reaction, the solvent in the system is replaced with new NMP and further concentrated to obtain a polyimide having an imidization rate of 58% (this is referred to as the polymer (PI-1)) containing 20% by mass. A solution was obtained. A small amount of this solution was taken and measured to have a solution viscosity of 490 mPa·s.

3. Synthesis of styrene-maleimide copolymer [Synthesis Example 2-1]
Under nitrogen, in a 100 mL two-necked flask, 20 mol parts of compound (MI-1), 10 mol parts of N-phenylmaleimide, 30 mol parts of 4-hydroxystyrene, 35 mol parts of glycidyl methacrylate, and 35 mol parts of methacrylic acid were added as polymerization monomers. 2 mol parts of 2,2′-azobis(2,4-dimethylvaleronitrile) as a radical polymerization initiator, and 50 ml of tetrahydrofuran as a solvent were added and polymerized at 70° C. for 5 hours. After reprecipitation in methanol, the precipitate was filtered and vacuum-dried at room temperature for 8 hours to obtain a styrene-maleimide copolymer (referred to as polymer (StMI-1)). The weight average molecular weight (Mw) measured in terms of polystyrene by GPC was 32000, and the molecular weight distribution (Mw/Mn) was 2.6.

[Synthesis Examples 2-2 and 2-3]
Polymerization was carried out in the same manner as in Synthesis Example 2-1, except that the types and amounts of the polymerization monomers were changed as shown in Table 2, to obtain polymers (StMI-2) and (StMI-2), which are styrene-maleimide copolymers. 3) were obtained respectively. In Table 2, the numerical values of the polymerized monomers represent the ratio (parts by mole) of each compound to 100 parts by moles of the total amount of the polymerized monomers used in the synthesis.

[Synthesis Example 2-4]
Using the compound (M-3) as a polymerization monomer, a polymer (PCD) having a cyclodextrin structure in its side chain was obtained according to the method described in Japanese Patent No. 6636610.

4. Synthesis of Polyorganosiloxane [Synthesis Example 3-1]
90.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 500 g of methyl isobutyl ketone, and 10.0 g of triethylamine were placed in a 1000 ml three-necked flask and mixed at room temperature. Then, 100 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and the reaction was carried out at 80° C. for 6 hours while mixing under reflux. After completion of the reaction, the organic layer was taken out and washed with a 0.2 mass % ammonium nitrate aqueous solution until the water after washing became neutral, and then the solvent and water were distilled off under reduced pressure. An appropriate amount of methyl isobutyl ketone was added to obtain a 50 mass % solution of a polymer (ESSQ-1), which is a polyorganosiloxane having epoxy groups.
In a 500 ml three-necked flask, 28.9 g of compound (CA-1) (50 mol% with respect to the amount of epoxy groups possessed by polymer (ESSQ-1)), 2.00 g of tetrabutylammonium bromide, polymer (ESSQ-1) 80 g of the containing solution and 239 g of methyl isobutyl ketone were added and stirred at 90° C. for 18 hours. After cooling to room temperature, the liquid separation washing operation was repeated 10 times with distilled water. After that, the organic layer was recovered, and after repeating concentration and NMP dilution twice with a rotary evaporator, the solid content concentration was adjusted to 10% by mass using NMP, and the NMP solution of the polymer (PSQ-1) was obtained. got

<Preparation and Evaluation of Liquid Crystal Aligning Agent>
[Example 1]
(1) Preparation of liquid crystal aligning agent (AL-1) To the solution containing the polymer (StMI-1) obtained in Synthesis Example 2-1, NMP and butyl cellosolve (BC) were added as solvents, and the solvent composition was NMP/BC. = 50/50 (mass ratio) and the solid content concentration was 4.0% by mass. A liquid crystal aligning agent (AL-1) was prepared by filtering this solution through a filter having a pore size of 0.2 μm.

(2) Adhesion evaluation to sealant Liquid crystal aligning agent (AL-1) is applied using a spinner on a glass substrate, pre-baked on a hot plate at 80 ° C. for 2 minutes, and then replaced with nitrogen. By heating (post-baking) in an oven at 230° C. for 30 minutes, a coating film having an average film thickness of 0.10 μm was formed. By repeating the same operation, two glass substrates each having a coating film formed thereon were produced. The polymer (StMI-1) contained in the liquid crystal aligning agent (AL-1) is molecularly designed as a polymer that undergoes a cross-linking reaction and disconnection of bonds between the polymers by heat. In this example, it is thought that the crosslinking reaction first progresses with the heating during post-baking to form the bonds between the polymers, and then the bonds between the polymers are cut by the subsequent heating.
Subsequently, an ODF sealant (manufactured by Sekisui Chemical Co., Ltd., S-WB42) was applied to the coating film of one glass substrate on which the coating film was formed so that the width was 1 mm, and another glass substrate was coated. They were laminated so that the coating film and the ODF sealant were in contact with each other. The applied sealant portion was irradiated with light of 30,000 J/m ² (converted to 365 nm) using a metal halide lamp, and then further heated in an oven at 120° C. for 1 hour. After heating, the adhesion of the film to the sealant was evaluated by measuring the adhesion force using a tension/compression tester manufactured by Imada Seisakusho (model number: SDWS-0201-100SL). It can be said that the higher the adhesive strength, the less likely the film is broken, and the higher the mechanical strength of the film. The evaluation was "Best (◎ ◎)" when the adhesion was 250 N/cm ² or more, "Excellent (◎)" when it was 200 N/cm ² or more and less than 250 N/cm ² , 150 N/cm ² or more and less than 200 N/cm ² "Good (○)", 100 N/cm ² or more and less than 150 N/cm ² "Fair (△)", and less than 100 N/cm ² was regarded as "defective (x)". As a result, in this example, the adhesive strength was 204 N/cm ² , and the adhesiveness was evaluated as "good (◯)".

(3) Film hardness evaluation Liquid crystal aligning agent (AL-1) was applied to a glass substrate using a spinner, prebaked on a hot plate at 80 ° C. for 2 minutes, and then replaced with nitrogen at 230 ° C. A coating film having an average film thickness of 0.10 μm was formed by heating (post-baking) in an oven for 30 minutes. Subsequently, the strength of the film formed on the glass substrate was measured with Nanoindenter TI-900 manufactured by Bruker. For the measurement, a diamond conical indenter with a curvature radius of 1 μm was used, and the film was scratched with a size of 10 μm while gradually increasing the load from 0 μN to 1000 μN over 15 seconds. (vertical load) was measured. It can be evaluated that the larger the load when the indenter is suddenly dented, the higher the film hardness and the higher the mechanical strength of the film. If the measured value of the load was 200 μN or less, it was “bad (x)”; (∘)”, when it was greater than 400 μN and 500 μN or less, it was evaluated as “excellent (⊚)”, and when it was greater than 500 μN, it was evaluated as “best (⊚)”.

[Examples 2 to 12 and Comparative Examples 1 to 3]
Liquid crystal aligning agents (AL-2) to (AL-12), (AR-1) to (AR-3) with the same solvent composition and solid content concentration as in Example 1 except that the formulation composition was changed as shown in Table 3. ) was prepared. Moreover, the adhesiveness of the film|membrane was evaluated like Example 1 using each liquid crystal aligning agent. Table 3 shows the evaluation results. In Table 3, "-" indicates that the compound was not used.

As shown in Table 3, Examples 1 to 12 using a liquid crystal aligning agent containing a polymer [P] are both "best (◎ ◎)" and "excellent (◎)" in film adhesion and film hardness. ” or “Good (◯)”, and the mechanical strength of the film was higher than that of Comparative Examples 1 to 3 that did not contain the polymer [P]. In particular, Examples 2 to 12 using the liquid crystal aligning agent containing the compound [A] together with the polymer [P] were evaluated as better than Example 1 in film adhesion and film hardness.

Claims (15)

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

(In formula (1), B ¹ and B ² are each independently a single bond or a divalent organic group. J ¹ is a divalent group containing a site that cleaves upon stimulation. m is 0 or 1. When m is 1, X ¹ is a crosslinkable group, and when m is 0, X ¹ is a group Z possessed by the polymer [P] or a compound different from the polymer [P] A group that forms a clathrate by interaction with ¹ and can be separated from the clathrate by stimulation.n is an integer of 1 to 3. "*" represents a bond.) A compound having two or more groups capable of forming a bond with the group X ¹ in the above formula (1) (excluding polymers), or a compound that interacts with the group X ¹ in the above formula (1) The liquid crystal aligning agent according to claim 1, further comprising a compound having two or more groups capable of forming a contact body. The liquid crystal aligning agent according to claim 1 or 2, wherein the stimulus for causing cleavage at ^J1 is at least one of light, heat and magnetic field. The liquid crystal aligning agent according to any one of claims 1 to 3, wherein said m is 1. J ¹ is an unsaturated 6-membered ring structure formed by an addition reaction between a conjugated diene and an alkene, a disulfide structure, an alkoxyamine structure, a diarylbiphenylfuranone structure, an oxime ether structure, an enamine structure, a (thio)urea structure, The liquid crystal aligning agent according to claim 4, which is a group having an acetal structure, an aminal structure, an imine structure, a pinacol structure, a benzyl ester structure, a nitrobenzyl structure, or a methoxyphenyl ether structure. X ¹ is an oxetanyl group, an oxiranyl group, a group having a Meldrum's acid structure, a cyclocarbonate group, a carboxy group, a protected carboxy group, an amino group, a protected amino group, a β-hydroxyamide group, a carbon-carbon unsaturated group. The liquid crystal aligning agent according to claim 4 or 5, which is a saturated bond-containing group, a thiol group, a protected thiol group, a group having a Kremn structure, a cyanate group, a protected isocyanate group, or an oxazoline group. The liquid crystal aligning agent according to any one of claims 4 to 6, further comprising a compound capable of reacting with the residue of ^J1 cleaved by stimulation. the m is 0;
The liquid crystal aligning agent according to any one of claims 1 to 3, wherein one of said X ¹ and said Z ¹ is a group having a cyclodextrin structure. The polymer [P] is at least one selected from the group consisting of polyamic acids, polyamic acid esters, polyimides, polyorganosiloxanes, and addition polymers, according to any one of claims 1 to 8. liquid crystal aligning agent. The liquid crystal aligning agent according to any one of claims 1 to 9, further comprising a polymer [Q] having no partial structure represented by formula (1). The liquid crystal aligning agent according to claim 10, wherein the polymer [Q] is at least one selected from the group consisting of polyamic acid, polyamic acid ester and polyimide. A liquid crystal alignment film formed using the liquid crystal alignment agent according to any one of claims 1 to 11. A step of applying the liquid crystal aligning agent according to any one of claims 1 to 11 onto a substrate;
cross-linking the polymer contained in the liquid crystal aligning agent on the substrate;
severing bonds or interactions between the polymers by applying a stimulus to the crosslinked polymers;
A method for manufacturing a liquid crystal alignment film, comprising: A liquid crystal device comprising the liquid crystal alignment film according to claim 12 . A polymer having a partial structure represented by the following formula (1A).

(In formula (1A), B ¹ and B ² are each independently a single bond or a divalent organic group. J ¹ is a divalent group containing a site that cleaves upon stimulation. X ¹ is a crosslinkable group, n is an integer of 1 to 3, and "*" represents a bond.)