JP2022067054A - Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal element, and manufacturing method for liquid crystal element - Google Patents

Abstract

To provide a liquid crystal alignment agent capable of improving adhesiveness of a film to a substrate.SOLUTION: A liquid crystal alignment agent contains: a polymer component; and a compound [A] to be at least one kind selected from a group composed of a compound represented in formula (1) and a compound represented in formula (2). In the formula (1), Y1 and Y2 are hydrogen atom or a monovalent organic group. Z1 is a (c+d)-valent organic group satisfying (i), (ii) or (iii): (i) a (c+d)-valent group whose carbon number is 1 to 8 where at least one methylene group of a saturated chain hydrocarbon group is replaced by -O-; (ii) a (c+d)-valent saturated hydrocarbon group or the like whose carbon number is 11 or larger; and (iii) -S-, -SO2- or -CO-. In formula (2), at least one of Y3, Y3 of Y4, and Y4 is a monovalent group represented by one of formula (Y-1) to formula (Y-6).SELECTED DRAWING: None

Description

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, a liquid crystal element, and a method for manufacturing a liquid crystal element.

The liquid crystal element includes a liquid crystal alignment film having a function of orienting liquid crystal molecules in the liquid crystal layer in a certain direction. The liquid crystal alignment film is generally formed on the substrate by applying a liquid crystal alignment agent in which the polymer component is dissolved in an organic solvent to the surface of the substrate and preferably heating the substrate.

In recent years, large-screen, high-definition liquid crystal televisions have become the mainstream, and small display terminals such as smartphones and tablet PCs have become widespread, and the demand for higher quality liquid crystal elements has increased more than before. Therefore, conventionally, various liquid crystal alignment agents have been proposed in order to improve the performance of the liquid crystal alignment film and to improve various characteristics of the liquid crystal element (see, for example, Patent Document 1). Patent Document 1 discloses that a compound having a structure in which a methylol group is bonded to an aromatic ring is contained in a liquid crystal alignment agent together with a polyimide or a polyimide precursor.

International Publication No. 2010/074269

Liquid crystal elements are not only used in display terminals such as personal computers as in the past, but also indoors and outdoors such as LCD TVs, car navigation systems, mobile phones, smartphones, information displays, phase difference films, and dimming films. It is used in a wide variety of applications regardless of. Further, as the usage is expanded, it is expected that the liquid crystal element will be used in a harsher environment than before. For example, the liquid crystal element may be backlit for a long time due to continuous driving for a long time, or may be used in a high temperature and high humidity environment. Further, by using the liquid crystal element in a harsh environment, the liquid crystal alignment film is easily peeled off from the substrate. On the other hand, if the liquid crystal alignment film is peeled off from the substrate, there is a concern that the display quality of the liquid crystal element may be deteriorated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid crystal alignment agent capable of improving the adhesion of a film to a substrate.

（式（１）中、Ｙ^１及びＹ^２は、それぞれ独立して、水素原子又は１価の有機基である。Ｘ^１及びＸ^２は、それぞれ独立して、水酸基、炭素数１～４のアルキル基又は炭素数１～４のアルコキシ基である。ａ１及びａ２は、それぞれ独立して、１～３の整数である。ｂ１及びｂ２は、それぞれ独立して、０～３の整数である。ただし、１≦ａ１＋ｂ１≦５及び１≦ａ２＋ｂ２≦５を満たす。Ｚ^１は、下記（ｉ）、（ｉｉ）又は（ｉｉｉ）を満たす（ｃ＋ｄ）価の有機基である。
（ｉ）飽和鎖状炭化水素基の少なくとも１個のメチレン基が－Ｏ－に置き換えられてなる炭素数１～８の（ｃ＋ｄ）価の基、飽和鎖状炭化水素基の少なくとも１個の水素原子がフッ素原子で置換され、かつ当該飽和鎖状炭化水素基の少なくとも１個のメチレン基が－Ｏ－に置き換えられてなる炭素数１～８の（ｃ＋ｄ）価の基、又は、飽和鎖状炭化水素基の少なくとも１個の水素原子がカルボキシル基で置換された炭素数２～８の（ｃ＋ｄ）価の基。
（ｉｉ）炭素数１１以上の（ｃ＋ｄ）価の飽和炭化水素基、又は、炭素数７以上の（ｃ＋ｄ）価の芳香族炭化水素基。
（ｉｉｉ）－Ｓ－、－ＳＯ_２－又は－ＣＯ－。
ｃ及びｄは、それぞれ独立して、１～３の整数である。ただし、上記（ｉｉｉ）の場合、ｃ＋ｄ＝２である。Ｙ^１、Ｙ^２、Ｘ^１及びＸ^２につき、同一の記号が式中に複数個存在する場合、同一の記号の基は互いに同一又は異なる。）

（式（２）中、Ｙ^３及びＹ^４は、それぞれ独立して、水素原子又は１価の有機基である。ただし、式（２）中のＹ^３及びＹ^４のうち少なくとも１個は、下記式（Ｙ－１）～式（Ｙ－６）のうちいずれかで表される１価の基である。Ｘ^３及びＸ^４は、それぞれ独立して、水酸基、炭素数１～４のアルキル基又は炭素数１～４のアルコキシ基である。ａ３及びａ４は、それぞれ独立して、１～３の整数である。ｂ３及びｂ４は、それぞれ独立して、０～３の整数である。ただし、１≦ａ３＋ｂ３≦５及び１≦ａ４＋ｂ４≦５を満たす。Ｚ^２は、（ｅ＋ｆ）価の有機基である。ｅ及びｆは、それぞれ独立して、１～３の整数である。Ｙ^３、Ｙ^４、Ｘ^３及びＸ^４につき、同一の記号が式中に複数個存在する場合、同一の記号の基は互いに同一又は異なる。）

（式（Ｙ－１）～式（Ｙ－６）中、Ｒ^ａ及びＲ^ｂは、それぞれ独立して、水素原子又は炭素数１～４のアルキル基である。「＊」は結合手であることを示す。） According to the present invention, the following means are provided.
[1] Contains a polymer component and a compound [A] which is at least one selected from the group consisting of a compound represented by the following formula (1) and a compound represented by the following formula (2). , Liquid crystal alignment agent.

(In the formula (1), Y ¹ and Y ² are independently hydrogen atoms or monovalent organic groups. X ¹ and X ² are independently hydroxyl groups and having 1 to 4 carbon atoms, respectively. It is an alkyl group or an alkoxy group having 1 to 4 carbon atoms. A1 and a2 are independently integers of 1 to 3, and b1 and b2 are independently integers of 0 to 3. However, 1 ≦ a1 + b1 ≦ 5 and 1 ≦ a2 + b2 ≦ 5 are satisfied. Z ¹ is a (c + d) valent organic group satisfying the following (i), (ii) or (iii).
(I) A (c + d) -valent group having 1 to 8 carbon atoms in which at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—, and at least one hydrogen of the saturated chain hydrocarbon group. A (c + d) -valent group having 1 to 8 carbon atoms or a saturated chain in which the atom is replaced with a fluorine atom and at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—. A (c + d) -valent group having 2 to 8 carbon atoms in which at least one hydrogen atom of a hydrocarbon group is substituted with a carboxyl group.
(Ii) A (c + d) -valent saturated hydrocarbon group having 11 or more carbon atoms or a (c + d) -valent aromatic hydrocarbon group having 7 or more carbon atoms.
(Iii) -S-, -SO _2- or -CO-.
c and d are independently integers of 1 to 3. However, in the case of the above (iii), c + d = 2. If more than one identical symbol is present in the equation for Y ¹ , Y ² , X ¹ and X ² , the groups of the same symbol are the same or different from each other. )

(In formula (2), Y ³ and Y ⁴ are independent hydrogen atoms or monovalent organic groups, respectively. However, at least one of Y ³ and Y ⁴ in formula (2) is It is a monovalent group represented by any of the following formulas (Y-1) to (Y-6). X ³ and X ⁴ are independently hydroxyl groups and alkyl having 1 to 4 carbon atoms, respectively. It is a group or an alkoxy group having 1 to 4 carbon atoms. A3 and a4 are independently integers of 1 to 3. b3 and b4 are independently integers of 0 to 3. , 1 ≦ a3 + b3 ≦ 5 and 1 ≦ a4 + b4 ≦ 5. Z ² is an organic group having a (e + f) valence. E and f are independently integers of 1 to ³ , respectively. If multiple identical symbols are present in the equation for Y ⁴ , X ³ and X ⁴ , the groups of the same symbol are the same or different from each other.)

(In the formulas (Y-1) to (Y-6 ^{), Ra and R b are} independently hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. “*” Is a bond. Indicates that.)

[2] A liquid crystal alignment film formed by using the liquid crystal alignment agent of the above [1].
[3] A liquid crystal element provided with the liquid crystal alignment film of the above [2].
[4] A step of applying the liquid crystal alignment agent of the above [1] on the respective conductive films of a pair of substrates having a conductive film to form a coating film, and a pair of substrates coated with the liquid crystal alignment agent. A liquid crystal display including a step of constructing a liquid crystal cell by arranging the coating films so as to face each other across the liquid crystal layer, and a step of irradiating the liquid crystal cell with light while a voltage is applied between the conductive films. Manufacturing method of the element.

（式（１）中、Ｙ^１及びＹ^２は、それぞれ独立して、水素原子又は１価の有機基である。Ｘ^１及びＸ^２は、それぞれ独立して、水酸基、炭素数１～４のアルキル基又は炭素数１～４のアルコキシ基である。ａ１及びａ２は、それぞれ独立して、１～３の整数である。ｂ１及びｂ２は、それぞれ独立して、０～３の整数である。ただし、１≦ａ１＋ｂ１≦５及び１≦ａ２＋ｂ２≦５を満たす。Ｚ^１は、飽和鎖状炭化水素基の少なくとも１個の水素原子がカルボキシル基で置換された炭素数２～８の（ｃ＋ｄ）価の基であるか、又は、飽和鎖状炭化水素基の少なくとも１個の水素原子がフッ素原子で置換され、かつ当該飽和鎖状炭化水素基の少なくとも１個のメチレン基が－Ｏ－に置き換えられてなる炭素数１～８の（ｃ＋ｄ）価の基である。ｃ及びｄは、それぞれ独立して、１～３の整数である。Ｙ^１、Ｙ^２、Ｘ^１及びＸ^２につき、同一の記号が式中に複数個存在する場合、同一の記号の基は互いに同一又は異なる。） [5] A compound represented by the following formula (1).

(In the formula (1), Y ¹ and Y ² are independently hydrogen atoms or monovalent organic groups. X ¹ and X ² are independently hydroxyl groups and having 1 to 4 carbon atoms, respectively. It is an alkyl group or an alkoxy group having 1 to 4 carbon atoms. A1 and a2 are independently integers of 1 to 3. b1 and b2 are independently integers of 0 to 3. However, 1 ≦ a1 + b1 ≦ 5 and 1 ≦ a2 + b2 ≦ 5 are satisfied. Z ¹ has a (c + d) valence of 2 to 8 carbon atoms in which at least one hydrogen atom of the saturated chain hydrocarbon group is substituted with a carboxyl group. At least one hydrogen atom of the saturated chain hydrocarbon group is replaced with a fluorine atom, and at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—. It is a group of (c + d) valences having 1 to 8 carbon atoms. C and d are independently integers of 1 to 3. The same for Y ¹ , Y ² , X ¹ and X ² . If more than one symbol is present in the formula, the groups of the same symbol are the same or different from each other.)

（式（２）中、Ｙ^３及びＹ^４は、それぞれ独立して、水素原子又は１価の有機基である。ただし、式（２）中のＹ^３及びＹ^４のうち少なくとも１個は、下記式（Ｙ－３）～式（Ｙ－５）のうちいずれかで表される１価の基である。Ｘ^３及びＸ^４は、それぞれ独立して、水酸基、炭素数１～４のアルキル基又は炭素数１～４のアルコキシ基である。ａ３及びａ４は、それぞれ独立して、１～３の整数である。ｂ３及びｂ４は、それぞれ独立して、０～３の整数である。ただし、１≦ａ３＋ｂ３≦５及び１≦ａ４＋ｂ４≦５を満たす。Ｚ^２は、（ｅ＋ｆ）価の有機基である。ｅ及びｆは、それぞれ独立して、１～３の整数である。Ｙ^３、Ｙ^４、Ｘ^３及びＸ^４につき、同一の記号が式中に複数個存在する場合、同一の記号の基は互いに同一又は異なる。）

（式（Ｙ－３）～式（Ｙ－５）中、Ｒ^ａ及びＲ^ｂは、それぞれ独立して、水素原子又は炭素数１～４のアルキル基である。「＊」は結合手であることを示す。） [6] A compound represented by the following formula (2).

(In formula (2), Y ³ and Y ⁴ are independent hydrogen atoms or monovalent organic groups, respectively. However, at least one of Y ³ and Y ⁴ in formula (2) is It is a monovalent group represented by any of the following formulas (Y-3) to (Y-5). X ³ and X ⁴ are independently hydroxyl groups and alkyl having 1 to 4 carbon atoms, respectively. It is a group or an alkoxy group having 1 to 4 carbon atoms. A3 and a4 are independently integers of 1 to 3. b3 and b4 are independently integers of 0 to 3. , 1 ≦ a3 + b3 ≦ 5 and 1 ≦ a4 + b4 ≦ 5. Z ² is an organic group having a (e + f) valence. E and f are independently integers of 1 to ³ , respectively. If there are multiple identical symbols in the equation for Y ⁴ , X ³ and X ⁴ , the groups of the same symbols are the same or different from each other.)

(In formulas (Y-3) to (Y-5 ^{), Ra and R b are} independently hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. “*” Is a bond. Indicates that.)

According to the liquid crystal alignment agent of the present invention, the liquid crystal alignment film having excellent adhesion to the substrate can be formed by containing the compound [A] together with the polymer component.

≪Liquid crystal alignment agent≫
The liquid crystal alignment agent of the present disclosure is at least one compound [A] selected from the group consisting of a polymer component, a compound represented by the above formula (1), and a compound represented by the above formula (2). And contains. Hereinafter, each component contained in the liquid crystal alignment agent and other components optionally blended will be described.

In addition, in this specification, a "hydrocarbon group" means a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The "chain hydrocarbon group" means a linear hydrocarbon group and a branched hydrocarbon group which do not contain a cyclic structure in the main chain and are composed only of a chain structure. However, it may be saturated or unsaturated. The "alicyclic hydrocarbon group" means a hydrocarbon group containing only the alicyclic hydrocarbon structure as the ring structure and not containing the aromatic ring structure. However, it does not have to be composed only of the alicyclic hydrocarbon structure, and some of them have a chain structure. The "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 include a chain structure or an alicyclic hydrocarbon structure as a part thereof.

<Polymer component>
The polymer component contained in the liquid crystal alignment agent may be crosslinked by the compound [A], and its main skeleton is not particularly limited. Examples of the polymer component include polyamic acid, polyamic acid ester, polyimide, polyamine, polyenamine, polyorganosiloxane, polyester, polyamide, polyamideimide, polystyrene, polybenzoxazole precursor, polybenzoxazole, cellulose derivative, polyacetal, and poly. Examples thereof include a maleimide, a styrene-maleimide-based copolymer, or a polymer having a poly (meth) acrylate as a main skeleton and having a functional group that reacts with compound [A] (crosslinking reaction). In addition, (meth) acrylate means acrylate and methacrylate. The polyenamine is a polymer having a carbon-carbon double bond adjacent to the amino group of the polyamine, and examples thereof include polyenaminoketone, polyenaminoester, polyenaminonitrile, and polyenaminosulfonyl.

Among these, the polymer component is a portion derived from a polyamic acid, a polyamic acid ester, a polyimide, or a monomer having a polymerizable unsaturated bond in that the liquid crystal orientation and voltage holding characteristics of the liquid crystal element can be improved. It is preferably at least one selected from the group consisting of a polymer having a structure and polyorganosiloxane. Among these, the liquid crystal alignment agent of the present disclosure comprises a polyamic acid, a polyamic acid ester, and a polyimide as polymer components in that the liquid crystal orientation and voltage holding characteristics can be improved and the degree of freedom in selecting a monomer is high. It is particularly preferable to include at least one polymer selected from the group (hereinafter, also referred to as "polymer (PA)").

In the liquid crystal alignment agent of the present disclosure, at least a part of the polymer (PA) contained in the liquid crystal alignment agent is "* ⁴ " in that the effect of improving the adhesion of the film by using the compound [A] can be enhanced. -NR ¹¹ R ¹² "," * ⁴ -NR ^13- * ⁵ "," * ⁴ -NR ¹⁴ -CO-NR ^15- * ⁵ "," * ⁴ -NR ¹⁶ -CO- * ⁵ ", and" * ⁴ -COOR ¹⁷ "(where R ¹¹ is a hydrogen atom or a monovalent organic group. R ¹² is a protective group. R ¹³ to R ¹⁷ are independent hydrogen atoms or protective groups, respectively. . "* ⁴ " and "* ⁵ " indicate at least one group selected from the group consisting of a group consisting of a carbon atom constituting a carbon-carbon bond (hereinafter, "specific group"). It is preferable to include a structural unit derived from a diamine having (also referred to as "A"). By using a polymer containing a structural unit having such a specific group A, the reaction of the compound [A] with the polymer component can be promoted, and the adhesion between the liquid crystal alignment film and the substrate can be further improved. preferable.

Here, in the specific group A, the monovalent organic group represented by R ¹¹ is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms or a protecting group.
The protecting group possessed by the specific group A is preferably a monovalent organic group (heat desorbable group) that is desorbed by heat. Specific examples of the amino-protecting group include a carbamate-based protecting group, an amide-based protecting group, an imide-based protecting group, a sulfonamide-based protecting group, and the like. Among these, a carbamate-based protecting group is preferable, and specific examples thereof include, for example, a tert-butoxycarbonyl group, a benzyloxycarbonyl group, a 1,1-dimethyl-2-haloethyloxycarbonyl group, and 1,1. Examples thereof include -dimethyl-2-cyanoethyloxycarbonyl group, 9-fluorenylmethyloxycarbonyl group, allyloxycarbonyl group, 2- (trimethylsilyl) ethoxycarbonyl group and the like. Of these, the tert-butoxycarbonyl group (Boc group) is particularly preferable because it has high desorption by heat and can discharge the compound derived from the group desorbed by heating during film formation to the outside of the membrane as a gas. ..
Examples of the carboxyl-protecting group (R ¹⁷ ) include a tert-butyl group, an acetal ester structure of a carboxylic acid, and a ketal ester structure of a carboxylic acid.

The specific group A may be introduced into either the main chain or the side chain of the polymer. It is preferable that the group "* ⁴ -NR ^13- * ⁵ " constitutes a part of the main chain of the polymer. Here, the "main chain" of the polymer means the longest "stem" portion of the atomic chain of the polymer. The "side chain" means a portion branched from the "stem" of the polymer.

（式中、「＊」は、炭素－炭素結合を構成する炭素原子との結合手であることを示す。） Specific examples of the specific group A include the groups shown below.

(In the formula, "*" indicates a bond with a carbon atom constituting a carbon-carbon bond.)

In a polymer (PA) containing a structural unit derived from a monomer having a specific group A, the content of the structural unit derived from the monomer having a specific group A is the total content of the polymer. With respect to the monomer unit, 2 mol% or more is preferable, 5 mol% or more is more preferable, and 10 mol% or more is further preferable. The content of the structural unit derived from the monomer having the specific group A is preferably 45 mol% or less, more preferably 40 mol% or less, and more preferably 30 mol, based on the total monomer unit of the polymer. % Or less is more preferable. As the specific group A contained in the polymer (PA), only one type may be used, or two or more types may be used.

The polymer component contained in the liquid crystal alignment agent of the present disclosure is a group capable of imparting a pretilt angle to liquid crystal molecules in the liquid crystal layer when the liquid crystal alignment film is arranged adjacent to the liquid crystal layer (hereinafter, "orientation"). It is preferable to have a "group"). The orientation group referred to here is a group capable of imparting a liquid crystal alignment ability to an organic film formed by a liquid crystal alignment agent without irradiating with light. Specific examples of the orienting group include an alkyl group having 4 to 20 carbon atoms, an alkoxy group having 4 to 20 carbon atoms, a fluoroalkyl group having 4 to 20 carbon atoms, and a fluoroalkoxy group having 4 to 20 carbon atoms. More than one ring (preferably at least one ring selected from the group consisting of cyclohexane ring, benzene ring and naphthalene ring) directly or divalent linking group (eg, oxygen atom, -CO- or -COO-). Examples thereof include a group having a mesogen structure formed by binding via a group, a group having a steroid skeleton, and the like.

The polymer component preferably contains, as the polymer having an oriented group, a polymer having a partial structure represented by the following formula (3).
* -L ¹ -R ¹ -R ² -R ³ -R ⁴ ... (3)
(In the formula (3), L ¹ is a single bond, -O-, -CO-, -COO- * ¹ , -OCO- * ¹ , -NR ^{25-, -NR 25 -CO-} * ¹ , -CO. -NR ^25- * ¹ , a divalent group in which the hydrogen atom of an alkanediyl group having 1 to 6 carbon atoms and an alkanediyl group having 2 to 6 carbon atoms is substituted with a hydroxyl group, -OR ^26- * ¹ , Or -R ²⁶ -O- * ¹ (where R ²⁵ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. R ²⁶ is an alkanediyl group having 1 to 3 carbon atoms. ¹ ”indicates that it is a bond with R ^1. ) R ¹ and R ³ are independently single-bonded, substituted or unsubstituted phenylene groups, or substituted or unsubstituted cycloalkylenes, respectively. R ² is a single-bonded, substituted or unsubstituted phenylene group, substituted or unsubstituted cycloalkylene group, or -R ²⁷ -B ¹ -R ^28- (where R ²⁷ and R ²⁸ are, respectively. Independently substituted or unsubstituted phenylene group or cycloalkylene group. B ¹ is a single bond, -O-, -COO- * ² , -OCO- * ² , -OCH _2- * ² , -CH ₂ It is an O- * ² or an alkanediyl group having 1 to 3 carbon atoms. "* ² " indicates that it is a bond with R ^28. ) R ⁴ is a hydrogen atom, a fluorine atom, and Cyan group, CH ₃ COO- * ³ (“* ³ ” indicates a bond with R ³ ), an alkyl group having 1 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, and carbon. An alkoxy group having 1 to 18 carbon atoms, a fluoroalkoxy group having 1 to 18 carbon atoms, a hydrocarbon group having 17 to 51 carbon atoms having a steroid skeleton, or a hydrogen atom having an alkyl group or fluoroalkyl group having 1 to 18 carbon atoms. Is a monovalent group substituted with a cyano group, where all of R ¹ , R ² and R ³ are single bonds, or the substituted or unsubstituted phenylene possessed by R ¹ , R ² and R ³ . When the total number of groups and cycloalkylene groups is 1, R ⁴ has an alkyl group having 4 to 18 carbon atoms, a fluoroalkyl group having 4 to 18 carbon atoms, an alkoxy group having 4 to 18 carbon atoms, and 4 to 18 carbon atoms. It is a fluoroalkoxy group of 18 or a hydrocarbon group having 17 to 51 carbon atoms having a steroid skeleton. “*” Indicates a bond.)

In the above formula (3), the alkanediyl group represented by L1 is preferably ^linear . Examples of the monovalent hydrocarbon group having 1 to 10 carbon atoms represented by ^R25 include a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group, and preferably 1 to 3 carbon atoms. It is an alkyl group of.
For ^R4 , an alkyl group having 1 to 18 carbon atoms, a fluoroalkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, a fluoroalkoxy group having 1 to 18 carbon atoms, or an alkyl having 1 to 18 carbon atoms. The monovalent group in which the hydrogen atom of the group or fluoroalkyl group is substituted with a cyano group is preferably linear. These groups preferably have 2 to 18 carbon atoms, more preferably 3 to 18 carbon atoms, and even more preferably 4 to 18 carbon atoms. Examples of the hydrocarbon group having a steroid skeleton of ^R4 and having 17 to 51 carbon atoms include a cholestanyl group, a cholesteryl group, a lanostannyl group and the like.

（式（３－１）～式（３－１０）中、Ｒ^２０は、フッ素原子、シアノ基、炭素数１～２０のアルキル基、炭素数１～２０のフルオロアルキル基、炭素数１～２０のアルコキシ基、又は炭素数１～２０のフルオロアルコキシ基である。Ｘ^２１は、－Ｏ－、－ＣＯＯ－又は炭素数１～３のアルカンジイル基である。「＊」は結合手であることを示す。） As the orientation group, from the viewpoint of obtaining a liquid crystal element showing good liquid crystal orientation, R ¹ , R ² and R ³ are at least one of a substituted or unsubstituted phenylene group and a substituted or unsubstituted cycloalkylene group. , It is preferable to have two or more in total of R ¹ , R ² and R ³ , and it is more preferable to have 2 to four.
Specific examples of the oriented group include groups represented by the following formulas (3-1) to (3-10).

(In formulas (3-1) to (3-10), R ²⁰ is a fluorine atom, a cyano group, an alkyl group having 1 to 20 carbon atoms, a fluoroalkyl group having 1 to 20 carbon atoms, and 1 to 20 carbon atoms. Alkoxy group or fluoroalkoxy group having 1 to 20 carbon atoms. X ²¹ is an -O-, -COO- or an alkanediyl group having 1 to 3 carbon atoms. "*" Is a bond. Shows.)

The liquid crystal alignment agent of the present disclosure preferably contains at least one polymer selected from the group consisting of polyamic acid, polyamic acid ester and polyimide as the polymer having an orientation group. In the polymer, the content of the structural unit having an oriented group is preferably 1 mol% or more, more preferably 3 mol% or more, and 5 mol% or more, based on the total amount of the monomer units of the polymer. Is more preferable. The content of the structural unit having an oriented group is preferably 40 mol% or less, more preferably 35 mol% or less, still more preferably 30 mol% or less, based on the total amount of the monomer units of the polymer. .. The orientation group contained in the polymer component may be only one type or two or more types.

Next, a preferable example of the polymer contained in the liquid crystal alignment agent of the present disclosure will be described.

(Polyamic acid)
The polyamic acid can be obtained by reacting a tetracarboxylic acid dianhydride with a diamine compound.

-Tetracarboxylic acid dianhydride Examples of the tetracarboxylic acid dianhydride used for the synthesis of polyamic acid include aliphatic tetracarboxylic acid dianhydride, alicyclic tetracarboxylic acid dianhydride, and aromatic tetracarboxylic acid dianhydride. You can mention things. Specific examples of these include, for example, 1,2,3,4-butanetetracarboxylic acid dianhydride as the aliphatic tetracarboxylic acid dianhydride;
Examples of the alicyclic tetracarboxylic acid dianhydride include 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, and the like. 2,3,5-Tricarboxycyclopentylacetic acid dianhydride, 5- (2,5-dioxotetratetra-3-yl) -3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1 , 3-Dione, 5- (2,5-dioxotetratetra-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 acid dianhydride, cyclohexanetetracarboxylic acid dianhydride, etc. As aromatic tetracarboxylic acid dianhydrides, for example, pyromellitic acid dianhydride, 4,4'-(hexafluoroisopropylidene) diphthalic acid anhydride, ethylene glycol bisanhydrotrimate, 4,4'-(hexa). Fluoroisopropylidene) diphthalic acid anhydride, 4,4'-carbonyldiphthalic acid anhydride, etc .; in addition to each, the tetracarboxylic acid dianhydride described in JP-A-2010-97188 can be used. can. As the tetracarboxylic acid dianhydride, one type can be used alone or two or more types can be used in combination.

The tetracarboxylic acid dianhydride used for the synthesis of polyamic acid is an aliphatic tetracarboxylic acid dianhydride and an alicyclic tetracarboxylic acid dianhydride in that a liquid crystal alignment film showing good voltage holding characteristics can be obtained. It is preferable to contain at least one selected from the group consisting of substances, and more preferably to contain an alicyclic tetracarboxylic acid dianhydride. The amount of the alicyclic tetracarboxylic dianhydride used is preferably 20 mol% or more, preferably 40 mol% or more, based on the total amount of the tetracarboxylic dianhydride used for the synthesis of the polyamic acid. Is more preferable, and 50 mol% or more is further preferable.

-Diamine compound As the diamine compound used for the synthesis of polyamic acid, a known diamine compound can be used. Examples of the diamine compound include aliphatic diamines, alicyclic diamines, aromatic diamines, diaminoorganosiloxanes and the like. The diamine compound used for the synthesis of the polyamic acid preferably contains a diamine having a specific group A in that it has high reactivity with the compound [A] by heating and can further promote cross-linking.

（式中、Ｂｏｃはｔｅｒｔ－ブトキシカルボニル基を示す。） Specific examples of the diamine having the specific group A include compounds represented by the following formulas (d-1-1) to (d-1-28).

(In the formula, Boc represents a tert-butoxycarbonyl group.)

When synthesizing a polymer containing a structural unit derived from a monomer having a specific group A as a polymer (PA), the amount of the diamine having the specific group A used is the amount of the diamine used in the synthesis of the polymer. 4 mol% or more is preferable, 10 mol% or more is more preferable, and 20 mol% or more is further preferable with respect to the total amount. The amount of the diamine having the specific group A is preferably 90 mol% or less, more preferably 80 mol% or less, still more preferably 60 mol% or less, based on the total amount of the diamine used for the synthesis of the polymer. .. In synthesizing the polymer (PA), as the diamine having a specific group A, one type may be used alone, or two or more types may be used in combination.

（式（Ｅ－１）中、Ｘ^I及びＸ^IIは、それぞれ独立に、単結合、－Ｏ－、＊－ＣＯＯ－又は＊－ＯＣＯ－（ただし、「＊」はＸ^Ｉとの結合手を示す。）であり、Ｒ^Ｉは炭素数１～３のアルカンジイル基であり、Ｒ^ＩＩは単結合又は炭素数１～３のアルカンジイル基であり、ａは０又は１であり、ｂは０～２の整数であり、ｃは１～２０の整数であり、ｄは０又は１である。但し、ａ及びｂが同時に０になることはない。）
で表される化合物等を挙げることができる。 When forming a liquid crystal alignment film for a vertically oriented type or PSA type liquid crystal element, it is preferable to use a diamine having an oriented group together with a diamine having a specific group A in the synthesis of the polymer (PA). The diamine having an oriented group is preferably a diamine having a partial structure represented by the above formula (3). Specific examples of the diamine having an orienting group include, for example, dodecanoxy-2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecanoxy-2,4-diaminobenzene, octadecanoxy-2,4-diaminobenzene, and the like. Pentadecanoxy-2,5-diaminobenzene, octadecanoxy-2,5-diaminobenzene, cholestanoloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholestanoloxy-2,4-diaminobenzene , Cholestenyloxy-2,4-diaminobenzene, 3,5-diaminobenzoate cholestanyl, 3,5-diaminobenzoate cholestenyl, 3,5-diaminobenzoate lanostannyl, 3,6-bis (4-aminobenzoyloxy) ) Cholestan, 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-cholestane-3-yl, the following formula (E-1)

(In the formula (E-1), X ^I and X ^II are independently single-bonded, -O-, * -COO- or * -OCO- (where "*" is a bond with X ^I. ), ^{RI is an alcandiyl group having 1 to 3 carbon atoms, R II is} a single bond or an alcandiyl group having 1 to 3 carbon atoms, a is 0 or 1, and b is 0. It is an integer of ~ 2, c is an integer of 1 to 20, d is 0 or 1. However, a and b cannot be 0 at the same time.)
Examples thereof include compounds represented by.

When synthesizing a polymer having an orienting group as a polymer (PA), the amount of diamine having an orienting group is preferably 2 mol% or more based on the total amount of diamine used for synthesizing the polymer. , 6 mol% or more is more preferable, and 10 mol% or more is further preferable. The amount of the diamine having an oriented group is preferably 80 mol% or less, more preferably 70 mol% or less, still more preferably 60 mol% or less, based on the total amount of the diamine used in the synthesis of the polymer. .. In synthesizing the polymer (PA), as the diamine having an orienting group, one kind may be used alone, or two or more kinds may be used in combination.

In addition to the above, as the diamine compound used for the synthesis of polyamic acid, as an aliphatic diamine, metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine and the like; As diamines, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), etc.;
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] hexane diic 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'-diaminostylbenzene, 1,4-bis (4-aminophenyl) -piperazine and the like; as diaminoorganosiloxane, for example. 1,3-Bis (3-aminopropyl) -tetramethyldisiloxane and the like can be mentioned, respectively; and the diamine described in JP-A-2010-97188 can be used.

In the synthesis of the polyamic acid, the amount of other diamines used is preferably 70 mol% or less, more preferably 60 mol% or less, still more preferably 50 mol% or less, based on the total amount of diamines used in the synthesis. In synthesizing the polymer, as the other diamine, one type may be used alone, or two or more types may be used in combination.

-Synthesis of polyamic acid The polyamic acid can be obtained by reacting the tetracarboxylic acid dianhydride as described above with a diamine compound, if necessary, with a molecular weight adjusting agent. The ratio of the tetracarboxylic acid dianhydride used in the polyamic acid synthesis reaction to the diamine compound is 0.2 for the acid anhydride group of the tetracarboxylic acid dianhydride with respect to 1 equivalent of the amino group of the diamine compound. A ratio of up to 2 equivalents is preferable. Examples of the molecular weight adjusting agent include 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 phenylisocyanate and naphthylisocyanate. Can be mentioned. The proportion of the molecular weight adjusting agent used is preferably 20 parts by mass or less with respect to 100 parts by mass in total of the tetracarboxylic acid dianhydride and the diamine compound used.

The polyamic acid synthesis reaction is preferably carried out in an organic solvent. The reaction temperature at this time is preferably −20 ° C. to 150 ° C., and the reaction time is preferably 0.1 to 24 hours.
Examples of the organic solvent used in the reaction include an aprotonic polar solvent, a phenol solvent, an alcohol, a ketone, an ester, an ether, a halogenated hydrocarbon, and a hydrocarbon. Particularly preferred organic solvents are N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide, m-cresol, xylenol. And one or more selected from the group consisting of halogenated phenol may be used as a solvent, or a mixture of one or more of these with another organic solvent (eg, butyl cellosolve, diethylene glycol diethyl ether, etc.) may be used. preferable. The amount (a) of the organic solvent used shall be such that the total amount (b) of the tetracarboxylic acid dianhydride and the diamine is 0.1 to 50% by mass with respect to the total amount (a + b) of the reaction solution. Is preferable.
As described above, a reaction solution obtained by dissolving a polyamic acid is obtained. This reaction solution may be used as it is for the preparation of the liquid crystal alignment agent, or the polyamic acid contained in the reaction solution may be isolated and then used for the preparation of the liquid crystal alignment agent.

(Polyamic acid ester)
The polyamic acid ester is, for example, [I] a method of reacting the polyamic acid obtained by the above synthetic reaction with an esterifying agent, [II] a method of reacting a tetracarboxylic acid diester with a diamine compound, and [III] tetracarboxylic. It can be obtained by a method of reacting an acid diester dihalide with a diamine compound, or 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 partial esterified product in which the amic acid structure and the amic acid ester structure coexist. The reaction solution obtained by dissolving the polyamic acid ester may be used as it is for the preparation of the liquid crystal alignment agent, or the polyamic acid ester contained in the reaction solution may be isolated and then used for the preparation of the liquid crystal alignment agent. good.

(Polyimide)
The polyimide can be obtained, for example, by dehydrating and ring-closing the polyamic acid synthesized as described above to imidize it. The polyimide may be a completely imidized product in which all of the amic acid structure possessed by its precursor polyamic acid is dehydrated and ring-closed, and only a part of the amic acid structure is dehydrated and ring-closed to form an amic acid structure and an imide. It may be a partially imidized product in which a ring structure coexists. The polyimide used in the reaction preferably has an imidization ratio of 20 to 99%, more preferably 30 to 90%. This imidization ratio is expressed as a percentage of the ratio of the number of imide ring structures to the total number of amic acid structures and the number of imide ring structures of polyimide. Here, a part of the imide ring may be an isoimide ring.

The dehydration ring closure of the polyamic acid is preferably carried out by dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring closure catalyst to this solution, and heating as necessary. In this method, as the dehydrating agent, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride can be used. 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. As the dehydration ring closure catalyst, for example, tertiary amines such as pyridine, colidine, lutidine, and triethylamine can be used. The amount of the dehydration ring closure catalyst used is preferably 0.01 to 10 mol with respect to 1 mol of the dehydrating agent used. Examples of the organic solvent used for the dehydration ring closure reaction include organic solvents exemplified as those used for the synthesis of polyamic acid. The reaction temperature of 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 thus obtained may be used as it is for the preparation of the liquid crystal alignment agent, or may be used for the preparation of the liquid crystal alignment agent after isolating the polyimide. Polyimide can also be obtained by imidization of polyamic acid esters.

When a liquid crystal alignment ability is imparted to an organic film formed by using a liquid crystal alignment agent by a photo-alignment method, it is preferable that at least a part of the polymer component is a polymer having a photo-orientation group. The photo-orientation group refers to a functional group capable of imparting anisotropy to the film by a photoreaction such as a photoisomerization reaction, a photodimerization reaction, a photofries rearrangement reaction, or a photodecomposition reaction by light irradiation.

Specific examples of the photoorienting group include an azobenzene-containing group containing azobenzene or a derivative thereof as a basic skeleton, a keishide structure-containing group containing keiseki acid or a derivative thereof (keiseki acid structure) as a basic skeleton, a chalcone or a derivative thereof. A chalcone-containing group containing benzophenone or a derivative thereof as a basic skeleton, a coumarin-containing group containing coumarin or a derivative thereof as a basic skeleton, a cyclobutane-containing structure containing cyclobutane or a derivative thereof as a basic skeleton, stilben or Examples thereof include a stilben-containing group having the derivative as a basic skeleton, a phenylbenzoate or a phenylbenzoate-containing group containing the derivative thereof as a basic skeleton. Of these, the photooriented group is preferably at least one selected from the group consisting of an azobenzene-containing group, a lauric acid structure-containing group, a chalcone-containing group, a stilbene-containing group, a cyclobutane-containing structure, and a phenylbenzoate-containing group. A stilbene structure-containing group or a cyclobutane-containing structure is preferable because of its high sensitivity to light and easy introduction into the polymer.

The polymer having a photo-orientation group can be obtained by, for example, (1) a method obtained by polymerization using a monomer having a photo-orientation group, (2) a polymer having an epoxy group in a side chain, and the synthesis thereof. It can be obtained by a method of reacting the obtained epoxy group-containing polymer with a carboxylic acid having a photo-orientation group, or the like. The content ratio of the photo-oriented group in the polymer can be appropriately set according to the type of the photo-oriented group so as to impart a desired liquid crystal orientation ability to the coating film. For example, in the case of a lauric acid structure-containing group, the content ratio of the photo-oriented group is preferably 5 mol% or more, preferably 10 to 60 mol%, based on all the structural units of the polymer having the photo-oriented group. It is more preferable to do so. When the photo-oriented group has a cyclobutane-containing structure, the content ratio of the photo-oriented group is preferably 50 mol% or more, preferably 80 mol% or more, based on all the constituent units of the polymer having the photo-oriented group. Is more preferable. As the polymer having a photo-oriented group, one type may be used alone, or two or more types may be used in combination.

The polymer component contained in the liquid crystal alignment agent may be one kind alone or a plurality of kinds. For example, the liquid crystal alignment agent contains a first polymer and a second polymer having a higher polarity than the first polymer. In this case, it is preferable that the second polymer having high polarity is unevenly distributed in the lower layer and the first polymer is unevenly distributed in the upper layer to cause phase separation. Preferred embodiments of the polymer component of the liquid crystal alignment agent include the following (I) to (III).
(I) An embodiment in which the first polymer and the second polymer are selected from the group consisting of polyamic acid, polyamic acid ester and polyimide.
(II) An embodiment in which one of the first polymer and the second polymer is a kind of polymer selected from the group consisting of polyamic acid, polyamic acid ester and polyimide, and the other is polyorganosiloxane.
(III) One of the first polymer and the second polymer is at least one polymer selected from the group consisting of polyamic acid, polyamic acid ester and polyimide, and the other has a polymerizable unsaturated bond. An embodiment of a polymer having a structural unit derived from a monomer having a polymer (hereinafter, also referred to as “polymer (Pm)”).

(Polyorganosiloxane)
The polyorganosiloxane contained in the liquid crystal alignment agent can be obtained, for example, by hydrolyzing and condensing a hydrolyzable silane compound. Examples of the hydrolyzable silane compound include alkoxysilane compounds such as tetramethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, and dimethyldiethoxysilane; 3-mercaptopropyltriethoxysilane and mercaptomethyl. Nitrogen / sulfur-containing alkoxysilane compounds such as triethoxysilane, 3-aminopropyltrimethoxysilane, N- (3-cyclohexylamino) propyltrimethoxysilane; 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl Epoxy group-containing silane compounds such as triethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane; 3- (meth) acryloxypropyltrimethoxysilane, 3- Unsaturated bond-containing alkoxysilane compounds such as (meth) acryloxypropylmethyldimethoxysilane, 3- (meth) acryloxipropylmethyldiethoxysilane, vinyltriethoxysilane, p-styryltrimethoxysilane; trimethoxysilylpropylsuccinic acid Anhydrous substances and the like can be mentioned. The hydrolyzable silane compound may be used alone or in combination of two or more. In addition, "(meth) acryloxy" means to include "acryloxy" and "methacryloxy".

The above hydrolysis / condensation reaction is 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 with respect to 1 mol of the silane compound (total amount). Examples of the catalyst 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, and should be set appropriately, but is preferably 0.01 to 3 times the molar amount of the total amount of the silane compound, for example. .. Examples of the organic solvent to be used include hydrocarbons, ketones, esters, ethers, alcohols and the like, and among these, it is preferable to use a water-insoluble or sparingly water-soluble organic solvent. The ratio of the organic solvent used is preferably 10 to 10,000 parts by mass with respect to 100 parts by mass in total of the silane compound used in the reaction.

The above hydrolysis / condensation reaction is preferably carried out by heating in, for example, 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 organic solvent layer separated from the reaction solution is dried with a desiccant, if necessary, and then the solvent is removed to obtain the desired polyorganosiloxane. The method for synthesizing the polyorganosiloxane is not limited to the above-mentioned hydrolysis / condensation reaction, and may be carried out by, for example, a method of reacting a hydrolyzable silane compound in the presence of oxalic acid and alcohol.

When the polyorganosiloxane is a polymer having a functional group such as an oriented group or a photo-oriented group, the synthesis method thereof is not particularly limited. For example, an epoxy group-containing silane compound is used as at least a part of the raw material to synthesize a polyorganosiloxane having an epoxy group in the side chain (hereinafter, also referred to as “epoxide group-containing polyorganosiloxane”), and then an epoxy group-containing polyorganosiloxane is synthesized. Examples thereof include a method of reacting a polyorganosiloxane with a carboxylic acid having a functional group. This method is preferable because it is simple and can increase the introduction rate of functional groups. In addition, a polyorganosiloxane having a functional group in the side chain may be synthesized by a reaction containing a hydrolyzable silane compound having a functional group in the monomer. For polyorganosiloxane, the polystyrene-equivalent weight average molecular weight (Mw) measured by GPC is preferably in the range of 100 to 50,000, more preferably in the range of 200 to 10,000.

(Polymer (Pm))
Examples of the monomer having a polymerizable unsaturated bond used for the synthesis of the polymer (Pm) include compounds having a (meth) acryloyl group, a vinyl group, a vinylphenyl group, a maleimide group and the like. The polymer (Pm) is a group consisting of poly (meth) acrylates, maleimide-based polymers and styrene-maleimide-based copolymers in that functional groups can be easily introduced and liquid crystal orientation is good. At least one selected from the above can be preferably used.

Specific examples of the monomer having a polymerizable unsaturated bond include unsaturated carboxylic acids such as (meth) acrylic acid, α-ethylacrylic acid, maleic acid, fumaric acid, and vinyl benzoic acid: alkyl (meth) acrylic acid (for example). , (Meta) Methyl Acrylic Acid, (Meta) Acrylic Acid-2-ethylhexyl, etc.), (Meta) Acrylic Acid Cycloalkyl, (Meta) Acrylic Acid benzyl, (Meta) Acrylic Acid Trimethoxysilylpropyl, (Meta) Acrylic Acid Unsaturated carboxylics such as 2-hydroxyethyl, glycidyl (meth) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, 3,4-epoxybutyl (meth) acrylate, 4-hydroxybutyl glycidyl ether acrylate. Acid ester: Unsaturated polyvalent carboxylic acid anhydride such as maleic anhydride: (meth) acrylic compound such as;
Aromatic vinyl compounds such as styrene, methylstyrene, divinylbenzene and 4- (glycidyloxymethyl) styrene; conjugated diene compounds such as 1,3-butadiene, 2-methyl-1,3-butadiene;
N-methylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, 4- (2,5-dioxo-3-pyrrolin-1-yl) benzoic acid, N- (4-glycidyloxyphenyl) maleimide, N-glycidylmaleimide , 3-Maleimide Benzoic Acid, 3-Maleimide Propionic Acid, 3- (2,5-dioxo-3-pyrrolin-1-yl) Benzoic Acid, 4- (2,5-dioxo-3-pyrrolin-1-yl) Maleimide compounds such as methyl benzoate, and the like can be mentioned. Further, when the polymer (Pm) is a polymer having a functional group, a compound having a functional group can also be used as a monomer having a polymerizable unsaturated bond. As the monomer having a polymerizable unsaturated bond, one type can be used alone or two or more types can be used in combination.

The polymer (Pm) can be obtained, for example, by polymerizing a monomer having a polymerizable unsaturated bond in the presence of a polymerization initiator. Examples of the polymerization initiator used include 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), and 2,2'-azobis (4-methoxy-2). , 4-Dimethylvaleronitrile) and other azo compounds 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 the monomers used in the reaction. The polymerization reaction is preferably carried out in an organic solvent. Examples of the organic solvent used in the reaction include alcohols, ethers, ketones, amides, esters, hydrocarbon compounds and the like, and diethylene glycol ethylmethyl ether, propylene glycol monomethyl ether acetate and the like are preferable. 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 should be 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 preferable. For the polymer (Pm), the polystyrene-equivalent weight average molecular weight (Mw) measured by GPC is preferably 250 to 500,000, more preferably 500 to 100,000.

In the above embodiments (II) and (III), the total content of the polyamic acid, the polyamic acid ester and the polyimide is contained in the liquid crystal alignment agent from the viewpoint of obtaining a liquid crystal element having sufficiently high liquid crystal orientation and voltage holding characteristics. It is preferably 20% by mass or more, more preferably 30% by mass or more, and further preferably 50 to 98% by mass with respect to the total amount of the polymer components. When imparting liquid crystal alignment ability to an organic film formed by using a liquid crystal alignment agent by a photoalignment method, at least one selected from the group consisting of polyorganosiloxane, poly (meth) acrylate and a styrene-maleimide-based copolymer. By using a polymer having a photo-oriented group as the seed, an alignment film having better liquid crystal orientation can be obtained, which is preferable.

The content ratio of the polymer component in the liquid crystal alignment agent is the total mass of the solid content contained in the liquid crystal alignment agent (total mass of the components other than the solvent of the liquid crystal alignment agent) from the viewpoint of sufficiently increasing the film strength. On the other hand, it is preferably 50% by mass or more, more preferably 60% by mass or more, and further preferably 70% by mass or more.

（式（１）中、Ｙ^１及びＹ^２は、それぞれ独立して、水素原子又は１価の有機基である。Ｘ^１及びＸ^２は、それぞれ独立して、水酸基、炭素数１～４のアルキル基又は炭素数１～４のアルコキシ基である。ａ１及びａ２は、それぞれ独立して、１～３の整数である。ｂ１及びｂ２は、それぞれ独立して、０～３の整数である。ただし、１≦ａ１＋ｂ１≦５及び１≦ａ２＋ｂ２≦５を満たす。Ｚ^１は、下記（ｉ）、（ｉｉ）又は（ｉｉｉ）を満たす（ｃ＋ｄ）価の有機基である。
（ｉ）飽和鎖状炭化水素基の少なくとも１個のメチレン基が－Ｏ－に置き換えられてなる炭素数１～８の（ｃ＋ｄ）価の基、飽和鎖状炭化水素基の少なくとも１個の水素原子がフッ素原子で置換され、かつ当該飽和鎖状炭化水素基の少なくとも１個のメチレン基が－Ｏ－に置き換えられてなる炭素数１～８の（ｃ＋ｄ）価の基、又は、飽和鎖状炭化水素基の少なくとも１個の水素原子がカルボキシル基で置換された炭素数２～８の（ｃ＋ｄ）価の基。
（ｉｉ）炭素数１１以上の（ｃ＋ｄ）価の飽和炭化水素基、又は、炭素数７以上の（ｃ＋ｄ）価の芳香族炭化水素基。
（ｉｉｉ）－Ｓ－、－ＳＯ_２－又は－ＣＯ－。
ｃ及びｄは、それぞれ独立して、１～３の整数である。ただし、上記（ｉｉｉ）の場合、ｃ＋ｄ＝２である。Ｙ^１、Ｙ^２、Ｘ^１及びＸ^２につき、同一の記号が式中に複数個存在する場合、同一の記号の基は互いに同一又は異なる。）

（式（２）中、Ｙ^３及びＹ^４は、それぞれ独立して、水素原子又は１価の有機基である。ただし、式（２）中のＹ^３及びＹ^４のうち少なくとも１個は、下記式（Ｙ－１）～式（Ｙ－６）のうちいずれかで表される１価の基である。Ｘ^３及びＸ^４は、それぞれ独立して、水酸基、炭素数１～４のアルキル基又は炭素数１～４のアルコキシ基である。ａ３及びａ４は、それぞれ独立して、１～３の整数である。ｂ３及びｂ４は、それぞれ独立して、０～３の整数である。ただし、１≦ａ３＋ｂ３≦５及び１≦ａ４＋ｂ４≦５を満たす。Ｚ^２は、（ｅ＋ｆ）価の有機基である。ｅ及びｆは、それぞれ独立して、１～３の整数である。Ｙ^３、Ｙ^４、Ｘ^３及びＸ^４につき、同一の記号が式中に複数個存在する場合、同一の記号の基は互いに同一又は異なる。）

（式（Ｙ－１）～式（Ｙ－６）中、Ｒ^ａ及びＲ^ｂは、それぞれ独立して、水素原子又は炭素数１～４のアルキル基である。「＊」は結合手であることを示す。） <Compound [A]>
The compound [A] is at least one selected from the group consisting of the compound represented by the following formula (1) and the compound represented by the following formula (2).

(In the formula (1), Y ¹ and Y ² are independently hydrogen atoms or monovalent organic groups. X ¹ and X ² are independently hydroxyl groups and having 1 to 4 carbon atoms, respectively. It is an alkyl group or an alkoxy group having 1 to 4 carbon atoms. A1 and a2 are independently integers of 1 to 3, and b1 and b2 are independently integers of 0 to 3. However, 1 ≦ a1 + b1 ≦ 5 and 1 ≦ a2 + b2 ≦ 5 are satisfied. Z ¹ is a (c + d) valent organic group satisfying the following (i), (ii) or (iii).
(I) A (c + d) -valent group having 1 to 8 carbon atoms in which at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—, and at least one hydrogen of the saturated chain hydrocarbon group. A (c + d) -valent group having 1 to 8 carbon atoms or a saturated chain in which the atom is replaced with a fluorine atom and at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—. A (c + d) -valent group having 2 to 8 carbon atoms in which at least one hydrogen atom of a hydrocarbon group is substituted with a carboxyl group.
(Ii) A (c + d) -valent saturated hydrocarbon group having 11 or more carbon atoms or a (c + d) -valent aromatic hydrocarbon group having 7 or more carbon atoms.
(Iii) -S-, -SO _2- or -CO-.
c and d are independently integers of 1 to 3. However, in the case of the above (iii), c + d = 2. If more than one identical symbol is present in the equation for Y ¹ , Y ² , X ¹ and X ² , the groups of the same symbol are the same or different from each other. )

(In formula (2), Y ³ and Y ⁴ are independent hydrogen atoms or monovalent organic groups, respectively. However, at least one of Y ³ and Y ⁴ in formula (2) is It is a monovalent group represented by any of the following formulas (Y-1) to (Y-6). X ³ and X ⁴ are independently hydroxyl groups and alkyl having 1 to 4 carbon atoms, respectively. It is a group or an alkoxy group having 1 to 4 carbon atoms. A3 and a4 are independently integers of 1 to 3. b3 and b4 are independently integers of 0 to 3. , 1 ≦ a3 + b3 ≦ 5 and 1 ≦ a4 + b4 ≦ 5. Z ² is an organic group having a (e + f) valence. E and f are independently integers of 1 to ³ , respectively. If multiple identical symbols are present in the equation for Y ⁴ , X ³ and X ⁴ , the groups of the same symbol are the same or different from each other.)

(In the formulas (Y-1) to (Y-6 ^{), Ra and R b are} independently hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. “*” Is a bond. Indicates that.)

(Compound represented by the above formula (1))
In the above formula (1), the monovalent organic group represented by Y ¹ and Y ² is a monovalent hydrocarbon group having 1 to 20 carbon atoms and at least one methylene group contained in the hydrocarbon group. Is a monovalent group in which is replaced with -O-, -S-, -CO-, -COO-, -NR ^b- , -CONR ^b- , etc. (R ^b is a hydrogen atom or 1 of 1 to 10 carbon atoms). Hydrocarbon group of valence), monovalent heterocyclic group and the like can be mentioned. When Y ¹ and Y ² are monovalent hydrocarbon groups, the monovalent hydrocarbon group has an alkyl group having 1 to 7 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, or a cycloalkyl group having 6 to 12 carbon atoms. Aryl groups are preferable, and alkyl groups having 1 to 7 carbon atoms are more preferable.

The monovalent organic group represented by Y ¹ and Y ² is preferably a group desorbed by heating during film formation. When Y ¹ and Y ² are groups desorbed by heat, a preferable specific example thereof is an ether-based protective group such as an alkyl group having 1 to 7 carbon atoms, a benzyl group, or a p-methoxybenzyl group; a methoxymethyl group. , Ethoxyethyl group, 2-tetrahydropyranyl group and other acetal-based protective groups; acetyl group, benzoyl group and other acyl-based protective groups; allyl group, metalryl group and other allyl-based protective groups; trimethylsilyl group, triethylsilyl group, tert -Cyril ether-based protective groups such as a butyldimethylsilyl group can be mentioned. Of these, ether-based protecting groups, acetal-based protecting groups or acetyl groups are preferable, and alkyl groups having 1 to 7 carbon atoms and 2-tetrahydropyranyl are preferable from the viewpoint of achieving both ease of desorption by heat and storage stability. Groups, methoxymethyl groups, 1-ethoxyethyl or acetyl groups are more preferred.

Of the above, Y ¹ and Y ² contain a hydrogen atom, an ether-based protecting group, an acetal-based protecting group, or an acetyl group from the viewpoint of improving the adhesion between the liquid crystal alignment film and the substrate and the storage stability of the liquid crystal alignment agent. A hydrogen atom, an alkyl group having 1 to 7 carbon atoms, an acetyl group, a 2-tetrahydropyranyl group, a methoxymethyl group or a 1-ethoxyethyl group are more preferable.

As X ¹ and X ² , a hydroxyl group, an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms is preferable.
A1 and a2 are preferably 2 or 3, respectively, from the viewpoint of sufficiently obtaining the effect of improving the adhesion between the liquid crystal alignment film and the substrate. A1 + b1 and a2 + b2 are preferably 2 or more, and more preferably 2 to 4, respectively.
For c and d, c + d is preferably 2 to 6 and more preferably 2 to 4 from the viewpoint of sufficiently obtaining the effect of improving the adhesion to the substrate and the balance with the storage stability.

When Z ¹ satisfies (i), Z ¹ is the following (Z1), (Z2) or (Z3).
(Z1) A (c + d) -valent group having 1 to 8 carbon atoms in which at least one methylene group of a saturated chain hydrocarbon group is replaced with —O—.
(Z2) At least one hydrogen atom of the saturated chain hydrocarbon group is replaced with a fluorine atom, and at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—. A group of (c + d) valences of ~ 8.
(Z3) A group having a (c + d) valence of 2 to 8 carbon atoms in which at least one hydrogen atom of a saturated chain hydrocarbon group is substituted with a carboxyl group.

In the above group (Z1), the saturated chain hydrocarbon group may be linear or branched. When the saturated chain hydrocarbon group is linear, the alignment film is formed even when the width of the sealant (seal width) is narrowed when the pair of substrates are bonded together via the sealant after the formation of the liquid crystal alignment film. It is preferable in that the adhesion between the substrate and the substrate (hereinafter, also referred to as “narrow-width adhesion”) can be improved. When the saturated chain hydrocarbon group is linear, c + d is preferably 2.

In the group (Z1), the position of the oxygen atom in the saturated chain hydrocarbon group is not particularly limited. The oxygen atom may be present between the carbon-carbon bonds of the saturated chain hydrocarbon group, at the end of the saturated chain hydrocarbon group (ie, the portion bonded to the benzene ring in formula (1)). It may be present, or it may be present both between carbon-carbon bonds and at the ends. Of these, the group (Z1) is preferably a group bonded with an oxygen atom to at least ^one benzene ring linked via Z1 in the formula ( ¹ ), and is linked via Z1. It is more preferable that the group is bonded with an oxygen atom to all of the benzene rings to be formed.
The number of oxygen atoms contained in the group (Z1) is preferably 2 or more, and more preferably 2 to 6 in that the narrow-width adhesion can be further increased.

The group (Z2) is a group in which at least one hydrogen atom bonded to a carbon atom in the group (Z1) is replaced with a fluorine atom. In the group (Z2), the saturated chain hydrocarbon group is preferably linear for the same reason as the group (Z1). As for the description of specific examples and preferable examples of the positions of oxygen atoms in the group (Z2), the above description of the group (Z1) is incorporated.

In the above group (Z3), the saturated chain hydrocarbon group may be linear or branched. Further, the position and number of carboxyl groups in the saturated chain hydrocarbon group are not particularly limited. The carboxyl group is an alkanediyl group with respect to the saturated chain hydrocarbon moiety connecting two or more benzene rings in the formula (1) in that a liquid crystal alignment film having higher narrow-width adhesion can be obtained. It is preferable that they are bonded via each other. In this case, it is preferable in that the degree of freedom of movement of the carboxyl group is increased and the self-crosslinking property can be enhanced.
The number of carboxyl groups contained in the group (Z3) is preferably 1 to 6 and more preferably 1 to 3 from the viewpoint of achieving both narrow adhesion and storage stability.

（式（１－ｚ－１）中、Ｒ^５は、炭素数１～８のアルカンジイル基、炭素数１～８のフルオロアルカンジイル基、又はアルカンジイル基の炭素－炭素結合間に－Ｏ－を含む炭素数２～８の２価の基である。Ｙ^１、Ｙ^２、Ｘ^１、Ｘ^２、ａ１、ａ２、ｂ１及びｂ２は、上記式（１）と同義である。）

（式（１－ｚ－２）中、Ｒ^８は、単結合又は（ｃ＋１）価の飽和鎖状炭化水素基である。Ｒ^９は、単結合又は（ｄ＋１）価の飽和鎖状炭化水素基である。Ｒ^１０は、（ｇ＋２）価の飽和鎖状炭化水素基である。Ｒ^１１は、アルカンジイル基である。ただし、Ｒ^８、Ｒ^９、Ｒ^１０及びＲ^１１の炭素数の合計は２～８である。ｇは、１～３の整数である。Ｙ^１、Ｙ^２、Ｘ^１、Ｘ^２、ａ１、ａ２、ｂ１、ｂ２、ｃ及びｄは、上記式（１）と同義である。） When Z ¹ satisfies (i), preferred specific examples of the compound represented by the above formula (1) include the compound represented by the following formula (1-z-1) and the following formula (1-z-2). ) Is mentioned.

(In the formula (1-z-1), R ⁵ is an alkanediyl group having 1 to 8 carbon atoms, a fluoroalkanediyl group having 1 to 8 carbon atoms, or an -O- between carbon-carbon bonds of the alkanediyl group. It is a divalent group having 2 to 8 carbon atoms including. Y ¹ , Y ² , X ¹ , X ² , a1, a2, b1 and b2 are synonymous with the above formula (1).

(In the formula (1-z-2), R ⁸ is a single bond or (c + 1) -valent saturated chain hydrocarbon group. R ⁹ is a single bond or (d + 1) -valent saturated chain hydrocarbon group. R ¹⁰ is a saturated chain hydrocarbon group with a (g + 2) valence. R ¹¹ is an alcandiyl group, where the total number of carbon atoms of R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ is 2 to 8. g is an integer of 1 to 3. Y ¹ , Y ² , X ¹ , X ² , a1, a2, b1, b2, c and d are synonymous with the above formula (1). be.)

In the above formula (1-z- ¹ ), R5 is preferably "* -O- (CH ₂ ) _h -O- *", "* -O- (CF ₂ ) _h -O- *" or A group represented by "* -O- (R ⁶ -O) _i- *" (where R ⁶ is an alkanediyl group having 2 to 4 carbon atoms. H is an integer of 1 to 8. i is an integer of 1 to 8. It is an integer of 1 to 4).
In the above formula (1-z-2), 1 or 2 is preferable, and 1 is more preferable, respectively, from the viewpoint of developing adhesion to the substrate and storage stability in a well-balanced manner.
g is preferably 1 or 2.

By including the compound in which Z ¹ in the above formula (1) satisfies (i) in the liquid crystal alignment agent, a liquid crystal alignment film having good adhesion to the substrate can be formed. In particular, even when the sealing width is narrowed in order to narrow the frame of the liquid crystal element for the purpose of securing the movable area as wide as possible in the touch panel type liquid crystal element and reducing the size of the display panel, the alignment film is also used. It is preferable in that it can form a liquid crystal alignment film having excellent adhesion between the surface and the substrate (that is, narrow-width adhesion). That is, according to the compound in which Z ¹ in the above formula (1) satisfies (i), it is possible to obtain a liquid crystal alignment film suitable for narrowing the frame of the liquid crystal element while having excellent adhesion to the substrate. Further, by using the compound as the cross-linking agent, it is possible to obtain a liquid crystal element exhibiting a high voltage retention rate even when the liquid crystal alignment agent containing the cross-linking agent is used. Of the groups (Z1) to (Z3), Z ¹ is preferably a group (Z1) or a group (Z3) in that it has high compatibility with a polymer component and can improve coatability and liquid crystal orientation. Is.

When Z ¹ satisfies (ii), Z ¹ is the following (Z4) or (Z5).
(Z4) A (c + d) -valent saturated hydrocarbon group having 11 or more carbon atoms.
(Z5) A (c + d) -valent aromatic hydrocarbon group having 7 or more carbon atoms.

（式（１－ｚ－３）中、Ｒ^１２は、（ｃ＋１）価の飽和鎖状炭化水素基又は脂環式基である。Ｒ^１３は、（ｄ＋１）価の飽和鎖状炭化水素基又は脂環式基である。Ｒ^１４及びＲ^１５は、それぞれ独立して、単結合又はアルカンジイル基である。Ｒ^１６は、アルカンジイル基又は脂環式構造を有する２価の基である。ただし、Ｒ^１２、Ｒ^１３、Ｒ^１４、Ｒ^１５及びＲ^１６の炭素数の合計は１１以上である。Ｒ^１２、Ｒ^１３及びＲ^１６のうち少なくともいずれかは脂環式構造を有する。Ｙ^１、Ｙ^２、Ｘ^１、Ｘ^２、ａ１、ａ２、ｂ１、ｂ２、ｃ及びｄは、上記式（１）と同義である。） When Z ¹ is a group (Z 4), it is preferable that Z ¹ (that is, a saturated hydrocarbon group) has an alicyclic structure. In this case, a preferable specific example of the compound represented by the above formula (1) is a compound represented by the following formula (1-z-3).

(In the formula (1-z-3), R ¹² is a (c + 1) -valent saturated chain hydrocarbon group or an alicyclic group. R ¹³ is a (d + 1) -valent saturated chain hydrocarbon group or an alicyclic group. The alicyclic groups R ¹⁴ and R ¹⁵ are independently single-bonded or alkylan diyl groups, respectively. R ¹⁶ is an alcandiyl group or a divalent group having an alicyclic structure. , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ have a total carbon number of 11 or more. At least one of R ¹² , R ¹³ and R ¹⁶ has an alicyclic structure. Y ¹ , Y ² , X ¹ , X ² , a1, a2, b1, b2, c and d are synonymous with the above formula (1).)

In the above formula (1-z-3), the alicyclic group represented by R ¹² and R ¹³ has (c + 1) or (d + 1) hydrogen atoms removed from the ring portion of the alicyclic hydrocarbon ring. It is a base. The alicyclic hydrocarbon ring preferably has 4 or more ring members, more preferably 5 or more ring members, and even more preferably 5 to 12 ring members, in that it can form a liquid crystal alignment film having high resistance to high temperature and high humidity. The cyclopentane ring, cyclohexane ring or cycloheptane ring is particularly preferable as the alicyclic structure of the group (Z4) from the viewpoint of easily obtaining the compound, adhesion to the substrate, and developing high temperature and high humidity resistance in a well-balanced manner.
It is preferable that at least one of R ¹² and R ¹³ is an alicyclic group, and it is more preferable that both are alicyclic groups, because the effect of improving high temperature and high humidity resistance is high.

The alkanediyl group represented by R ¹⁴ and R ¹⁵ may be linear or branched. R ¹⁴ and R ¹⁵ are preferably a single bond or an alkanediyl group having 1 to 5 carbon atoms, and more preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms.

（式（ｒ－１）中、Ｒ^１７は、アルカンジイル基である。Ｒ^１８は、単結合又はアルカンジイル基である。Ｒ^１９は、１価の脂環式基である。「＊」は結合手であることを示す。） The alkanediyl group represented by R ¹⁶ may be linear or branched. When R ¹⁶ is an alkanediyl group, the number of carbon atoms is preferably 1 to 10, and more preferably 1 to 5 carbon atoms. When at least one of R ¹² and R ¹³ is an alicyclic group, R ¹⁶ is preferably an alkanediyl group. When R ¹⁶ is a divalent group having an alicyclic structure, examples of R ¹⁶ include a group represented by the following formula (r-1).

(In the formula (r-1), R ¹⁷ is an alkanediyl group. R ¹⁸ is a single bond or an alkanediyl group. R ¹⁹ is a monovalent alicyclic group. “*” Is a monovalent alicyclic group. Indicates that it is a bond.)

In the formula (r-1), R ¹⁷ preferably has 1 to 3 carbon atoms. ^R18 is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms. R ¹⁹ is preferably a substituted or unsubstituted cyclohexylene group. Examples of the substituent include a methyl group, an ethyl group, a fluorine atom and the like.
C and d are preferably 2 or 3, respectively, and more preferably 2 in that the resistance to high temperature and high humidity can be further increased.
The total number of carbon atoms of R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ and R ¹⁶ is preferably 40 or less, more preferably 30 or less, from the viewpoint of improving the coatability and suppressing the uneven orientation.

（式（１－ｚ－４）中、Ｒ^２０は、単結合又は（ｃ＋１）価の飽和鎖状炭化水素基である。Ｒ^２１は、単結合又は（ｄ＋１）価の飽和鎖状炭化水素基である。Ｒ^２２は、芳香環構造を有する２価の基である。ただし、Ｒ^２０、Ｒ^２１及びＲ^２２の炭素数の合計は７以上である。Ｙ^１、Ｙ^２、Ｘ^１、Ｘ^２、ａ１、ａ２、ｂ１、ｂ２、ｃ及びｄは、上記式（１）と同義である。Ｒ^２０が単結合の場合、ｃは１である。Ｒ^２１が単結合の場合、ｄは１である。） When Z ¹ is a group (Z 5), examples of the aromatic ring contained in Z ¹ (that is, an aromatic hydrocarbon group) include a benzene ring, a naphthalene ring, an anthracene ring, and a fluorene ring. When Z ¹ is the group (Z5), a preferable specific example of the compound represented by the above formula (1) is a compound represented by the following formula (1-z-4).

(In the formula (1-z-4), R ²⁰ is a single bond or (c + 1) -valent saturated chain hydrocarbon group. R ²¹ is a single bond or (d + 1) -valent saturated chain hydrocarbon group. R ²² is a divalent group having an aromatic ring structure. However, the total number of carbon atoms of R ²⁰ , R ²¹ and R ²² is 7 or more. Y ¹ , Y ² , X ¹ , X. ² , a1, a2, b1, b2, c and d are synonymous with the above formula (1). When R ²⁰ is a single bond, c is 1. When R ²¹ is a single bond, d is 1. Is.)

（式（ｒ－２－１）中、Ｒ^２３は、アルカンジイル基である。Ｒ^２４は、単結合又はアルカンジイル基である。Ｒ^２５は、１価の芳香環基である。式（ｒ－２－２）中、Ｒ^ｂは置換基である。ｔは０～４の整数である。「＊」は結合手であることを示す。） In the above formula (1-z-4), R ²² is preferably a group represented by the following formula (r-2-1) or a group represented by the following formula (r-2-2).

(In the formula (r-2-1), R ²³ is an alkanediyl group. R ²⁴ is a single bond or an alkanediyl group. R ²⁵ is a monovalent aromatic ring group. In -2-2), R ^b is a substituent. T is an integer from 0 to 4. "*" Indicates a bond.)

In the formula (r-2-1), R ²³ may be linear or branched. The carbon number of R ²³ is preferably 1 to 3. R ²⁴ is preferably a single bond or an alkanediyl group having 1 to 3 carbon atoms. R ²⁵ is preferably a substituted or unsubstituted phenyl group or naphthyl group. Examples of the substituent include a methyl group, an ethyl group, a fluorine atom and the like.

In the formula (r-2-2), examples of the substituent represented by R ^b include a halogen atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, an acetyl group and the like. t is preferably 0 to 2.

c and d are preferably 1 or 2, respectively, and more preferably 1.
The total number of carbon atoms of R ²⁰ , R ²¹ and R ²² is preferably 40 or less, more preferably 30 or less, from the viewpoint of improving coatability and suppressing uneven orientation.

By including the compound in which Z ¹ in the above formula (1) satisfies (ii) in the liquid crystal alignment agent, a liquid crystal alignment film having good adhesion to the substrate can be formed. Further, the above-mentioned structure of Z ¹ is highly hydrophobic, and by containing such a compound [A] in a liquid crystal alignment agent, performance deterioration is unlikely to occur even when exposed to a high temperature and high humidity environment, and high temperature and high humidity resistance is achieved. It is preferable in that an excellent liquid crystal alignment film can be formed. That is, according to the compound in which Z ¹ in the above formula (1) satisfies (ii), it is possible to obtain a liquid crystal alignment film having excellent high temperature and high humidity resistance in addition to adhesion to a substrate. Further, by using the compound as a cross-linking agent, it is preferable in that a liquid crystal element exhibiting a high voltage holding ratio can be obtained even when a liquid crystal alignment agent containing a cross-linking agent is used.

（式（１－ｚ－５）中、Ｚ^３は、－Ｓ－、－ＳＯ_２－又は－ＣＯ－である。Ｙ^１、Ｙ^２、Ｘ^１、Ｘ^２、ａ１、ａ２、ｂ１及びｂ２は、上記式（１）と同義である。） If Z ¹ satisfies (iii), then Z ¹ is -S-, -SO _2- or -CO-. In this case, the compound represented by the above formula (1) can be represented by the following formula (1-z-5).

(In equation (1-z-5), Z ³ is -S-, -SO _2- or -CO-. Y ¹ , Y ² , X ¹ , X ² , a1, a2, b1 and b2 are. , Synonymous with the above equation (1).)

Z ³ in the formula (1-z-5) can form a liquid crystal alignment film having excellent adhesion to the substrate even when the temperature at the time of film formation is high (for example, 200 ° C. or higher). S- or -SO _2- is preferable, and -SO _2- is more preferable.

By including the compound in which Z ¹ in the above formula (1) satisfies (iii) in the liquid crystal alignment agent, a liquid crystal alignment film having good adhesion to the substrate can be formed. Further, by incorporating the compound [A] in which the structure showing an electron-withdrawing group is introduced into Z ¹ in the above formula (1) in the liquid crystal alignment agent, the temperature at the time of film formation (post-baking temperature) is raised to a high temperature. Even in this case, the liquid crystal alignment film is less likely to peel off from the substrate, and the liquid crystal alignment film having excellent adhesion to the substrate can be formed, which is preferable. It is conceivable to raise the post-bake temperature in the manufacturing process to shorten the film forming step, but according to the compound in which Z ¹ in the above formula (1) satisfies (iii), the post-bake temperature is raised. However, it is suitable because the film does not easily peel off, the process compatibility range is wide, and the decrease in manufacturing yield can be suppressed. Further, by using the compound as a cross-linking agent, it is preferable in that a liquid crystal element exhibiting a high voltage holding ratio can be obtained even when a liquid crystal alignment agent containing a cross-linking agent is used.

As a specific example of the compound represented by the above formula (1), each of the following formulas (1-1-1) to (1-1-13) can be used as a compound when Z ¹ satisfies (i). The compounds represented by the following formulas (1-2-1) to (1-2-12) are used as compounds when Z ¹ satisfies (ii); Z ¹ Examples of the compound in which (iii) is satisfied include compounds represented by the following formulas (1-3-1) to (1-3-9). As the compound represented by the above formula (1), one kind may be used alone, or two or more kinds may be used in combination.

(Compound represented by the above formula (2))
In the above formula (2), the monovalent organic group represented by Y ³ and Y ⁴ is a monovalent hydrocarbon group having 1 to 20 carbon atoms and at least one methylene group contained in the hydrocarbon group. Is a monovalent group in which is replaced with -O-, -S-, -CO-, -COO-, -NR ^b- , -CONR ^b- , etc. (R ^b is a hydrogen atom or 1 of 1 to 10 carbon atoms). Hydrocarbon group of valence), monovalent heterocyclic group and the like can be mentioned. When Y ³ and Y ⁴ are monovalent hydrocarbon groups, the monovalent hydrocarbon group has an alkyl group having 1 to 7 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, or a cycloalkyl group having 6 to 12 carbon atoms. An aryl group is preferable, an alkyl group having 4 to 7 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms or an aryl group having 6 to 12 carbon atoms is more preferable, and an alkyl group having 4 to 7 carbon atoms is further preferable.

The monovalent organic group represented by Y ³ and Y ⁴ is preferably a group desorbed by heating during film formation. When Y ³ and Y ⁴ are groups desorbed by heat, preferred specific examples thereof include ether-based protective groups such as alkyl groups having 1 to 7 carbon atoms, benzyl groups, and p-methoxybenzyl groups; methoxymethyl groups, Acetal-based protective groups such as ethoxyethyl group and 2-tetrahydropyranyl group; Acyl-based protective groups such as acetyl group and benzoyl group; Allyl-based protective groups such as allyl group and metalryl group; trimethylsilyl group, triethylsilyl group, tert- Examples thereof include a silyl ether-based protective group such as a butyldimethylsilyl group. Further, a (meth) acryloyl group may be introduced into the compound represented by the above formula (2) as a monovalent organic group represented by Y ³ and Y ⁴ . Of these, an ether-based protecting group, an acetal-based protecting group, or an acetyl group is preferable, and an alkyl group having 1 to 7 carbon atoms, a 2-tetrahydropyranyl group, a methoxymethyl group, and 1 -Ethoxyethyl or acetyl groups are more preferred.

In the compound represented by the above formula (2), at least one of Y ³ and Y ⁴ in the above formula (2) is represented by any of the above formulas (Y-1) to (Y-6). Is the basis for being done. By containing such a compound in the liquid crystal alignment agent, the adhesion of the liquid crystal alignment film to the substrate is enhanced, and when the liquid crystal alignment film is peeled off from the substrate and the substrate is reused (reworked) in the manufacturing process of the liquid crystal element or the like. In addition, it is suitable in that the liquid crystal alignment film can be easily peeled off from the substrate (reworkability can be improved). Further, by using the compound represented by the above formula (2) as the cross-linking agent, it is preferable in that a liquid crystal element showing a high voltage retention rate can be obtained even when the liquid crystal alignment agent containing the cross-linking agent is used. be. From the viewpoint of achieving both adhesion to the substrate and reworkability of the liquid crystal alignment film, Y ³ and Y ⁴ are the above-mentioned formulas (Y-1) to (Y-6), and the above-mentioned formula (Y-2). A group represented by any of the above formulas (Y-6) is preferable, and the above formulas (Y-2) and (Y-) can be obtained in that a liquid crystal element having good liquid crystal orientation and voltage retention can be obtained. 4) The group represented by any of (Y-6) is more preferable, and an alkyl group having 4 to 7 carbon atoms, a 2-tetrahydropyranyl group, a methoxymethyl group, a 1-ethoxyethyl group or an acetyl group is particularly preferable. ..

Of Y ³ and Y ⁴ in the above formula (2), the total number of groups represented by any of the above formulas (Y-1) to (Y-6) has good adhesion to the substrate. From the viewpoint of obtaining a liquid crystal alignment film, two or more are preferable, and from the viewpoint of obtaining a liquid crystal alignment film showing a good balance between adhesion to a substrate and reworkability, all of Y ³ and Y ⁴ in the above formula (2) are used. It is particularly preferable that the group is represented by any of the above formulas (Y-1) to (Y-6). The compound represented by the above formula (2) may have only one type of groups represented by the above formulas (Y-1) to (Y-6), and may have two or more types. You may.

As X ³ and X ⁴ , a hydroxyl group, an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms is preferable.
Z ² includes a (e + f) -valent chain hydrocarbon group having 1 to 12 carbon atoms, an (e + f) -valent alicyclic hydrocarbon group having 3 to 12 carbon atoms, and a (e + f) -valent group having 6 to 12 carbon atoms. Aromatic hydrocarbon groups and the like can be mentioned. Of these, Z ² is preferably a (e + f) -valent linear or branched chain hydrocarbon group having 1 to 12 carbon atoms, and is preferably a (e + f) -valent linear or branched hydrocarbon group having 1 to 10 carbon atoms. Saturated chain hydrocarbon groups are more preferred.
A3 and a4 are preferably 2 or 3, respectively, from the viewpoint of sufficiently obtaining the effect of improving the adhesion between the liquid crystal alignment film and the substrate. A3 + b3 and a4 + b4 are preferably 2 or more, and more preferably 2 to 4, respectively.
For e and f, e + f is preferably 2 to 6 and more preferably 2 to 4 from the viewpoint of sufficiently obtaining the effect of improving the adhesion to the substrate and the balance with the storage stability.

By incorporating the compound represented by the above formula (2) as a cross-linking agent in the liquid crystal alignment agent, a liquid crystal alignment film having good adhesion to the substrate can be formed. Further, by introducing specific groups represented by the above formulas (Y-1) to (Y-6) into Y ³ and Y ⁴ in the above formula (2), a liquid crystal alignment film having excellent reworkability is obtained. It is preferable in that it can form.

Specific examples of the compound represented by the above formula (2) include compounds represented by the following formulas (2-1-1) to (2-1-10). As the compound represented by the above formula (2), one kind may be used alone, or two or more kinds may be used in combination.

The content of the compound [A] in the liquid crystal alignment agent is 0 with respect to 100 parts by mass of the total amount of the polymer components contained in the liquid crystal alignment agent in that the effect of improving the adhesion to the substrate can be sufficiently enhanced. It is preferably 5.5 parts by mass or more, more preferably 1 part by mass or more, and further preferably 2 parts by mass or more. Further, the content of the compound [A] is 100 parts by mass in total of the polymer components contained in the liquid crystal alignment agent from the viewpoint of suppressing the deterioration of performance due to the addition of an excessive amount and improving the storage stability. On the other hand, it is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and further 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.

<Other ingredients>
The liquid crystal alignment agent of the present disclosure may further contain a polymer component and other compounds other than the compound [A], if necessary. Specific examples thereof include epoxy compounds (eg, N, N, N', N'-tetraglycidyl-m-xylylene diamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N. , N', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N, N-diglycidyl-aminomethylcyclohexane, 1,6-hexanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, etc.), Functional silane compounds (eg, 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, etc.), antioxidants, metal chelate compounds, cure accelerators, surfactants, etc. Examples include fillers, dispersants, photosensitizers and the like. The content of other compounds can be appropriately selected according to each compound within a range that does not impair the effects of the present disclosure. When a compound different from the compound [A] is used in combination as the cross-linking agent, the content of the different compound is preferably 5% by mass or less with respect to the total amount of the compound [A] contained in the liquid crystal alignment agent. It is more preferably 1% by mass or less.

(solvent)
The liquid crystal alignment agent of the present disclosure is prepared as a liquid composition in which a polymer component, compound [A] and, if necessary, a component optionally blended are preferably dissolved in a solvent. The solvent is preferably an organic solvent, and examples thereof include an aprotonic polar solvent, a phenol solvent, an alcohol, a ketone, an ester, an ether, a halogenated hydrocarbon, and a hydrocarbon.
Specific examples of the organic solvent used include, for example, 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, ethylethoxypropi Onet, 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 Diethyl 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, diisobutylketone, 3-methoxy-1-butanol and the like. These can be used alone or in admixture of two or more.

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

≪Liquid crystal alignment film and liquid crystal element≫
The liquid crystal alignment film of the present disclosure is formed by the liquid crystal alignment agent prepared as described above. Further, the liquid crystal element of the present disclosure includes a liquid crystal alignment film formed by using the liquid crystal alignment agent described above. The operation mode of the liquid crystal in the liquid crystal element is not particularly limited, and for example, TN type, STN type, VA type (including VA-MVA type, VA-PVA type, etc.), IPS (In-Plane Switching) type, FFS (Fringe). It can be applied to various modes such as Field Switching) type, OCB (Optically Compensated Bend) type, and PSA type (Polymer Sustained Alignment). The liquid crystal element can be manufactured, for example, by a method including the following steps 1 to 3. In step 1, the substrate used differs depending on the desired operation mode. Step 2 and step 3 are common to each operation mode.

<Step 1: Formation of coating film>
First, a liquid crystal alignment agent is applied on the substrate, and preferably the coated surface is heated to form a coating film on the substrate. As the substrate, for example, glass such as float glass and soda glass; a transparent substrate made of a resin such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and poly (lipid ring type olefin) can be used. As the transparent conductive film provided on one surface of the substrate, a NESA film made of tin oxide (SnO ₂ ) (registered trademark of PPG Corporation in the United States), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), and the like are used. Can be used. When manufacturing a TN type, STN type or VA type liquid crystal element, two substrates provided with a patterned transparent conductive film are used. On the other hand, in the case of manufacturing an IPS type or FFS type liquid crystal element, a substrate provided with a comb-shaped patterned electrode and a facing substrate not provided with an electrode are used. The liquid crystal alignment agent is applied to the substrate on the electrode forming surface, preferably by an offset printing method, a flexographic printing method, a spin coating method, a roll coater method, or an inkjet printing method.

After the liquid crystal alignment agent is applied, preheating is preferably performed for the purpose of preventing the applied liquid crystal alignment agent from dripping. The prebake temperature is preferably 30 to 200 ° C., and the prebake time is preferably 0.25 to 10 minutes. After that, a firing (post-baking) step is carried out for the purpose of completely removing the solvent. The firing temperature (post-baking temperature) at this time is preferably 80 to 250 ° C, more preferably 80 to 200 ° C. The post-bake time is preferably 5 to 200 minutes. The film thickness of the film thus formed is preferably 0.001 to 1 μm.

<Step 2: Orientation treatment>
When manufacturing a TN type, STN type, IPS type or FFS type liquid crystal element, a treatment (alignment treatment) for imparting a liquid crystal alignment ability to the coating film formed in the above step 1 is performed. As a result, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film. The 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, and cotton, and the coating film formed on the substrate is irradiated with light. A photo-alignment treatment or the like that imparts a liquid crystal alignment ability to the coating film can be used. On the other hand, in the case of manufacturing a vertically oriented (VA) type liquid crystal element, the coating film formed in the above step 1 can be used as it is as a liquid crystal alignment film, but in order to further enhance the liquid crystal alignment ability, the coating film is used. The film may be oriented. A liquid crystal alignment film suitable for a vertically oriented liquid crystal element can also be suitably used for a PSA type liquid crystal element.

In the photoalignment process, the light irradiation includes a method of irradiating the coating film after the post-baking step, a method of irradiating the coating film after the pre-baking step and before the post-baking step, and a pre-baking step and a post-baking step. At least one of them can be used by a method of irradiating the coating film while heating the coating film, or the like. As the radiation to irradiate the coating film, for example, ultraviolet rays including light having a wavelength of 150 to 800 nm and visible light can be used. Preferably, it is ultraviolet light containing light having a wavelength of 200 to 400 nm. When the radiation is polarized, it may be linearly polarized or partially polarized. When the radiation to be used is linearly polarized light or partially polarized radiation, the irradiation may be performed from a direction perpendicular to the substrate surface, may be performed from an oblique direction, or may be performed in combination thereof. In the case of unpolarized radiation, the irradiation direction is diagonal.

Examples of the light source used include a low pressure mercury lamp, a high pressure mercury lamp, a deuterium hydrogen lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excima laser and the like. The irradiation amount of radiation on the substrate surface is preferably 400 to 50,000 J / m ² , and more preferably 1,000 to 20,000 J / m ² . After irradiation with light to impart orientation ability, the surface of the substrate is washed 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. Or a process of heating the substrate may be performed.

<Step 3: Construction of LCD cell>
Two substrates on which the liquid crystal alignment film is formed as described above are prepared, and the liquid crystal cell is manufactured so that the liquid crystal is arranged adjacent to the liquid crystal alignment film between the two substrates. 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 the peripheral portions of the two substrates are bonded with a sealant, and the substrate surface and the sealant are attached. Examples thereof include a method of injecting and filling a liquid crystal display in a cell gap surrounded by, and a method of sealing an injection hole, a method by an ODF method, and the like. As the sealing agent, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as a spacer can be used. Examples of the liquid crystal include a nematic liquid crystal and a smectic liquid crystal, and among them, the nematic liquid crystal is preferable. 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.

When manufacturing a PSA type liquid crystal element, the liquid crystal element can be manufactured by a method including the following three steps.
A step of applying the liquid crystal alignment agent of the present disclosure on each conductive film of a pair of substrates having a conductive film to form a coating film.
-A process of constructing a liquid crystal cell by arranging a pair of substrates coated with a liquid crystal alignment agent so that the coating films face each other across the liquid crystal layer.
-A process of irradiating a liquid crystal cell with light while a voltage is applied between the conductive films.

Specifically, first, a liquid crystal cell is constructed in the same manner as in steps 1 to 3 above, except that a photopolymerizable monomer is injected or dropped together with the liquid crystal between a pair of substrates having a conductive film. As the photopolymerizable monomer, a conventionally known compound can be used. Preferably, it is a polyfunctional (meth) acrylic monomer.
After that, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates. The voltage applied here can be, for example, a direct current or an alternating current of 5 to 50 V. As the light to be irradiated, for example, ultraviolet rays including light having a wavelength of 150 to 800 nm and visible light can be used. Of these, ultraviolet rays containing light having a wavelength of 300 to 400 nm are preferable. As the light source of the irradiation light, for example, a low pressure mercury lamp, a high pressure mercury lamp, a deuterium hydrogen lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excima laser and the like can be used. The irradiation amount of light is preferably 1,000 to 200,000 J / m ² , and more preferably 1,000 to 100,000 J / m ² .

For the liquid crystal cell in each mode, a polarizing plate is subsequently attached 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 polyvinyl alcohol is stretched and oriented and iodine is absorbed is sandwiched between a cellulose acetate protective film, or a polarizing plate made of the H film itself.

The liquid crystal element 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, LCD TVs, information displays, etc. , Dimming film, retardation film and the like.

Hereinafter, the present invention will be specifically described 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 ratio of the polymer were measured by the following methods.
<Solution viscosity of polymer>
The solution viscosity of the polymer was measured at 25 ° C. using an E-type viscometer.
<Weight average molecular weight and number average molecular weight>
Mw and Mn were measured by gel permeation chromatography (GPC) under the following conditions. The molecular weight distribution (Mw / Mn) was calculated from the obtained Mw and Mn.
Equipment: Showa Denko Corporation "GPC-101"
GPC column: Combines "GPC-KF-801", "GPC-KF-802", "GPC-KF-803" and "GPC-KF-804" manufactured by Shimadzu GLC Co., Ltd. Mobile phase: Tetrahydrofuran (THF) )
Column temperature: 40 ° C
Flow velocity: 1.0 mL / min Sample concentration: 1.0 mass%
Sample injection amount: 100 μL
Detector: Differential refractometer Standard material: Monodisperse polystyrene <Imidization rate of polyimide>
The polyimide solution was poured into pure water, the obtained precipitate was sufficiently dried under reduced pressure at room temperature, then dissolved in deuterated dimethyl sulfoxide, and ¹ H-NMR measurement was performed at room temperature using tetramethylsilane as a reference substance. .. From the obtained ¹ H-NMR spectrum, the imidization rate [%] was determined by the following mathematical formula (1).
Imidization rate [%] = (1- (β ¹ / (β ² × α))) × 100… (1)
(In formula (1), β ¹ is the peak area derived from the proton 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 ratio of the number 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 the formula (X)" may be simply referred to as "compound (X)".
・ Monomer and side chain carboxylic acid

-Compound [A]

<Synthesis of polymer>
1. 1. Polyimide synthesis [Synthesis example 1]
70 parts of 2,3,5-tricarboxycyclopentylacetic anhydride as tetracarboxylic acid dianhydride, 30 parts of pyromellitic acid dianhydride, and cholestanyloxy-2,4-diaminobenzene 30 as diamine. Polyamic by dissolving a molar part, 40 parts of compound (D-4), and 30 parts of 3,5-diaminobenzoic acid in N-methyl-2-pyrrolidone (NMP) and reacting at 40 ° C. for 24 hours. A solution containing 20% by mass of acid was obtained. Next, NMP was added to the obtained polyamic acid solution, and pyridine and acetic anhydride were added in an amount of 3.00 molar equivalents to the carboxyl group of the polyamic acid, and a dehydration ring closure reaction was carried out at 80 ° C. for 4 hours. After the dehydration ring closure reaction, the solvent in the system is replaced with a new γ-butyrolactone and further concentrated to obtain a polyimide having an imidization ratio of 63% (referred to as “polymer (P-1)”). A solution containing mass% was obtained. A small amount of this solution was taken, NMP was added, and the solution was measured as a solution having a concentration of 10% by mass, and the solution viscosity was 37 mPa · s.

[Synthesis Examples 2, 9 to 16]
Polymerization was carried out in the same manner as in Synthesis Example 1 except that the types and amounts of the tetracarboxylic acid dianhydride and the diamine used for the polymerization were changed as shown in Table 1. Solutions containing P-9) to (P-16) were obtained.

2. 2. Synthesis of polyamic acid [Synthesis example 3]
70 parts of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic acid dianhydride, 30 parts of 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, and cholestanol as diamine. 30 parts of oxy-2,4-diaminobenzene, 40 parts of 3,5-diamino-N, N-bis (pyridine-3-ylmethyl) benzamide, and 30 parts of 3,5-diaminobenzoic acid are dissolved in NMP. Then, the reaction was carried out at 40 ° C. for 24 hours to obtain a solution containing 20% by mass of a polyamic acid (referred to as “polymer (P-3)”). A small amount of this solution was taken, NMP was added, and the solution was measured as a solution having a concentration of 10% by mass, and the solution viscosity was 42 mPa · s.

[Synthesis Examples 4-8, 17]
Polymerization was carried out in the same manner as in Synthesis Example 3 except that the types and amounts of the tetracarboxylic acid dianhydride and the diamine used for the polymerization were changed as shown in Table 1, and the polymer (P-4) to be a polyamic acid. Solutions containing (P-8) and (P-17) were obtained. In Table 1, the numerical value of the acid anhydride represents the ratio (molar part) of each compound to 100 mol parts of the total amount of the tetracarboxylic dianhydride used for the synthesis. The numerical value of diamine represents the ratio (molar part) of each compound to 100 mol parts of the total amount of diamine used for synthesis.

3. 3. Synthesis of polyorganosiloxane [Synthesis Example 18]
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 then 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, washed with a 0.2 mass% ammonium nitrate aqueous solution until the washed water 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% by mass solution of a polymer (ESSQ-1) which is a polyorganosiloxane having an epoxy group.
In a 500 ml three-necked flask, 6.28 g of compound (C-1) (20 mol% with respect to the amount of epoxy group contained in the polymer (ESSQ-1)) and 3.44 g of compound (C-3) (polymer (ESSQ-). 10 mol% with respect to the amount of epoxy group contained in 1), 2.00 g of tetrabutylammonium bromide, 80 g of a polymer (ESSQ-1) -containing solution, and 239 g of methylisobutylketone were added, and the mixture was stirred at 90 ° C. for 18 hours. After cooling to room temperature, the liquid separation washing operation with distilled water was repeated 10 times. Then, the organic layer was recovered, and concentration and NMP dilution were repeated twice with a rotary evaporator, and then adjusted to a solid content concentration of 10% by mass using NMP to obtain an NMP solution of the polymer (PS-1). Got

[Synthesis Example 19]
The polymer (PS-2) which is a polyorganosiloxane is contained in an amount of 10% by mass in the same manner as in Synthesis Example 18 except that the type and amount of the side chain carboxylic acid used in the reaction are changed as shown in Table 2. An NMP solution was obtained. In Table 2, the numerical value of the side chain carboxylic acid represents the ratio (side chain modification rate, mol%) to the amount of the epoxy group possessed by the polymer (ESSQ-1).

4. Synthesis of styrene-maleimide-based polymer [Synthesis Example 20]
Under nitrogen, in a 100 mL two-necked flask, 10 mol parts of compound (M-1), 10 mol parts of compound (M-4), 35 mol parts of methacrylic acid, and 45 mol parts of glycidyl methacrylate were subjected to radical polymerization as polymerization monomers. 2 mol of 2,2'-azobis (2,4-dimethylvaleronitrile) as an agent and 50 ml of tetrahydrofuran as a solvent were added, and the mixture was 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 the desired polymer (PM-1). The weight average molecular weight Mw measured by GPC in terms of polystyrene was 30,000, and the molecular weight distribution Mw / Mn was 2.

[Synthesis Examples 21, 22]
Polymers (PM-2) and (PM-), which are styrene-maleimide-based copolymers, are the same as in Synthesis Example 20 except that the types and amounts of the polymerization monomers used in the reaction are changed as shown in Table 3. 3) were obtained respectively. In Table 3, the numerical value of the monomer represents the ratio (molar portion) of each compound to 100 mol parts of the total amount of the monomer used for the synthesis.

5. Preparation and evaluation of liquid crystal alignment agent (1)
[Example 1: PSA type liquid crystal display element]
(1) Preparation of liquid crystal alignment agent (AL-1) In a solution containing 100 parts by mass of the polymer (P-1) obtained in Synthesis Example 1, 5 parts by mass of compound (Ad-1), and NMP and butyl cellosolve as solvents (BC) was added to prepare a solution having a solvent composition of NMP / BC = 50/50 (mass ratio) and a solid content concentration of 4.0% by mass. A liquid crystal alignment agent (AL-1) was prepared by filtering this solution with a filter having a pore size of 0.2 μm.

(2) Evaluation of reworkability A liquid crystal alignment agent (AL-1) is applied with a spinner on a transparent conductive film made of an ITO film provided on one surface of a glass substrate having a thickness of 1 mm, and the temperature is 100 ° C. on a hot plate. , Prebaking was performed for 90 seconds to form a coating film having a film thickness of about 0.10 μm. This operation was repeated to prepare two substrates with a coating film. Next, the two obtained substrates were stored in a dark room at 25 ° C. under a nitrogen atmosphere. After 12 hours and 48 hours from the start of storage, one substrate was taken out, immersed in a beaker containing NMP whose temperature was adjusted to 40 ° C. for 2 minutes, washed several times with ultrapure water, and blown with air. Water droplets on the surface were removed. The ease of peeling (reworkability) of the liquid crystal alignment film from the substrate was evaluated by observing this substrate with an optical microscope and examining the presence or absence of residue of the coating film. The evaluation was that even if the substrate was taken out 48 hours after the start of storage, the reworkability was "good (○)" when no residue of the coating film was observed after NMP immersion, and the substrate after 48 hours was evaluated as having a coating film. Reworkability is "possible (△)" when residue is observed but not on the substrate after 12 hours, and reworkability is "defective (×)" when residue of the coating film is observed on the substrate after 12 hours. ) ”. As a result, the reworkability was "good (○)" in this example.

(3) Evaluation of film adhesion The liquid crystal alignment agent (AL-1) was applied onto a glass substrate using a spinner, prebaked on a hot plate at 80 ° C. for 2 minutes, and then the inside of the refrigerator was replaced with nitrogen 230. By heating (post-baking) in an oven at ° 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 on which the coating film was formed were produced. An ODF sealant (S-WB42, manufactured by Sekisui Chemical Co., Ltd.) is applied on the coating film of one glass substrate on which the coating film is formed so that the width is 1 mm, and the coating film is combined with the other glass substrate. They were bonded so that they would come into contact with the ODF sealant. Then, after irradiating with light of 30,000 J / m ² (365 nm conversion) using a metal halide lamp, it was heated in an oven at 120 ° C. for 1 hour. Then, the adhesion of the film to the substrate was evaluated by measuring the adhesion force using a tensile compression tester (model number: SDWS-0201-100SL) manufactured by Imada Seisakusho. The evaluation was "good (○)" when the adhesion was 175 N / cm ² or more, "possible (Δ)" when the adhesion was 150 N / cm ² or more and less than 175 N / cm ² , and less than 150 N / cm ² . If it was, it was regarded as "defective (x)". As a result, in this example, the adhesion was 192 N / cm ² , and the adhesion was evaluated as "good (◯)".

(4) Preparation of Liquid Crystal Composition 5% by mass of the liquid crystal compound represented by the following formula (L1-1) is added to 10 g of nematic liquid crystal (MLC-6608, manufactured by Merck), and the following formula (L2-1). 0.3% by mass of the photopolymerizable compound represented by (1) was added and mixed to obtain a liquid crystal composition LC1.

(5) Manufacture of PSA-type liquid crystal display element The liquid crystal alignment agent (AL-1) prepared above is applied onto each electrode surface of two glass substrates each having a conductive film composed of ITO electrodes patterned in a slit shape. It is applied using a liquid crystal alignment film printing machine (manufactured by Nissha Printing Co., Ltd.), heated (prebaked) on a hot plate at 80 ° C for 2 minutes to remove the solvent, and then placed on a hot plate at 230 ° C for 10 minutes. It was heated (post-baked) to form a coating film having an average film thickness of 0.06 μm. These coating films were ultrasonically cleaned in ultrapure water for 1 minute and then dried in a 100 ° C. clean oven for 10 minutes to obtain a pair (2 sheets) of substrates having a liquid crystal alignment film. The pattern of the electrodes used is the same as the electrode pattern in the PSA mode.
Next, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 μm was applied to the outer edge of the surface of one of the pair of substrates having the liquid crystal alignment film, and then the liquid crystal alignment film surfaces were overlapped so as to face each other. They were crimped together and the adhesive was cured. Next, a liquid crystal cell was manufactured by filling the liquid crystal composition LC1 prepared above between the pair of substrates from the liquid crystal injection port and then sealing the liquid crystal injection port with an acrylic photocurable adhesive. After that, an AC 10V having a frequency of 60 Hz was applied between the conductive films of the liquid crystal cell, and while the liquid crystal was being driven, an irradiation amount of 100,000 J / m ² was used using an ultraviolet irradiation device using a metal halide lamp as a light source. Irradiated with ultraviolet rays. It should be noted that this irradiation amount is a value measured using a photometer measured based on a wavelength of 365 nm. After that, polarizing plates are attached to both outer sides of the substrate so that their polarization directions are orthogonal to each other and the direction of projection of the optical axis of the liquid crystal alignment film on the substrate surface is 45 °. , PSA type liquid crystal display element was manufactured.

(6) Evaluation of liquid crystal orientation With respect to the PSA type liquid crystal display element manufactured above, the presence or absence of abnormal domains in the change in brightness when a voltage of 5 V is turned ON / OFF (applied / canceled) is observed with an optical microscope, and abnormalities are observed. The liquid crystal orientation was evaluated as "A" when there was no domain, "B" when there was an abnormal domain in part, and "C" when there was an abnormal domain as a whole. As a result, in this example, the liquid crystal orientation was "A".

(7) Evaluation of voltage retention rate (VHR) For the PSA type liquid crystal display element manufactured above, a voltage of 5 V was applied for an application time of 60 microseconds and a span of 167 milliseconds, and then 167 milliseconds after the application was released. The voltage retention rate of was measured. A VHR-1 manufactured by Toyo Corporation was used as the measuring device. At this time, "S" when the voltage holding ratio is 98% or more, "A" when 95% or more and less than 98%, "B" when 80% or more and less than 95%, 50% or more and less than 80%. In the case of "C", in the case of less than 50%, it was set as "D". As a result, in this example, the voltage holding ratio was evaluated as "A".

[Examples 2, 3, 5]
A liquid crystal alignment agent was prepared with the same solvent composition and solid content concentration as in Example 1 except that the compounding composition was changed as shown in Table 4. Further, using each liquid crystal alignment agent, the reworkability and the adhesion of the film are evaluated in the same manner as in Example 1, and the PSA type liquid crystal display element is manufactured to evaluate the liquid crystal orientation and the voltage retention rate. rice field. The results are shown in Table 4. In Table 4, "-" indicates that the compound was not used.

[Comparative Example 1]
A liquid crystal alignment agent (AR-1) was prepared with the same type of polymer, solvent composition and solid content concentration as in Example 1 except that the compound (Ad-1) was not blended. Further, using the prepared liquid crystal alignment agent, the reworkability and the adhesion of the film are evaluated in the same manner as in Example 1, and the PSA type liquid crystal display element is manufactured to evaluate the liquid crystal orientation and the voltage retention rate. rice field. The results are shown in Table 4.

[Example 4: Optical vertical liquid crystal display element]
(1) Preparation of liquid crystal alignment agent and evaluation of reworkability and film adhesion The liquid crystal alignment agent (AL-) has the same solvent composition and solid content concentration as in Example 1 except that the compounding composition is changed as shown in Table 4. 4) was prepared. Moreover, the reworkability and the adhesion of the film were evaluated in the same manner as in Example 1 using the liquid crystal alignment agent (AL-4). The results are shown in Table 4.

(2) Manufacture of Optical Vertical Liquid Crystal Display Element The liquid crystal alignment agent (AL-4) prepared above is applied to the transparent electrode surface of a glass substrate with a transparent electrode made of an ITO film using a spinner, and the temperature is 80 ° C. Pre-baked for 1 minute on the hot plate of. Then, the inside of the oven was heated at 230 ° C. for 1 hour in a nitrogen-substituted oven to form a coating film having a film thickness of 0.1 μm. Next, the surface of this coating film is irradiated with polarized ultraviolet rays of 1,000 J / m ² containing a emission line of 313 nm using an Hg-Xe lamp and a Gran Tailor prism from a direction inclined by 40 ° from the substrate normal, and the liquid crystal alignment ability. Was granted. The same operation was repeated to prepare a pair (two sheets) of substrates having a liquid crystal alignment film.
An epoxy resin adhesive containing aluminum oxide spheres having a diameter of 3.5 μm is applied to the outer periphery of the surface of one of the above substrates having a liquid crystal alignment film by screen printing, and then the liquid crystal alignment film surfaces of the pair of substrates are opposed to each other. The adhesive was heat-cured at 150 ° C. for 1 hour by pressure-bonding so that the projection directions of the optical axes of the ultraviolet rays of each substrate on the substrate surface were antiparallel. Next, a negative liquid crystal display (MLC-6608, manufactured by Merck & Co., Inc.) was filled in the gap between the substrates from the liquid crystal injection port, and then the liquid crystal injection port was sealed with an epoxy adhesive. Further, in order to remove the flow orientation at the time of liquid crystal injection, this was heated at 130 ° C. and then slowly cooled to room temperature. Next, the polarizing plates are attached to both outer sides of the substrate so that their polarization directions are orthogonal to each other and the liquid crystal alignment film is at an angle of 45 ° with the projection direction of the optical axis of the ultraviolet rays on the substrate surface. Manufactured an optical vertical liquid crystal display element.

(3) Evaluation of Liquid Crystal Orientation The liquid crystal orientation of the optical vertical liquid crystal display element manufactured above was evaluated in the same manner as in Example 1 above. As a result, in this example, the liquid crystal orientation was "A".
(4) Evaluation of Voltage Retention Rate (VHR) The voltage retention rate of the optical vertical liquid crystal display element manufactured above was evaluated in the same manner as in Example 1. As a result, in this example, the voltage holding ratio was evaluated as "A".

[Reference Examples 1A and 2A]
As an additive, compound (Ad-12) or compound (Ad-14) was used instead of compound [A], and the same solvent composition and solid content as in Example 1 except that the compounding composition was changed as shown in Table 4. Liquid crystal alignment agents (AR-2) and (AR-3) were prepared at different concentrations. Further, using each liquid crystal alignment agent, the reworkability and the adhesion of the film were evaluated in the same manner as in Example 1, and the PSA type liquid crystal display element was manufactured to evaluate the liquid crystal orientation and the voltage retention rate. .. The results are shown in Table 4.

As shown in Table 4, Examples 1 to 5 containing the compound (Ad-1), (Ad-2) or (Ad-3) had a membrane as compared with Comparative Example 1 in which no cross-linking agent was added. Adhesion and reworkability were good. Further, in Examples 1 to 5, the liquid crystal orientation and the voltage retention rate were also evaluated as "A", which were good.

In Reference Examples 1A and 2A in which other cross-linking agents (Ad-12) and (Ad-14) were used instead of the compound [A], the film adhesion was good, but the reworkability was poor. there were. Further, Reference Examples 1A and 2A were also inferior to Examples 1 to 5 in terms of voltage holding ratio.

6. Preparation and evaluation of liquid crystal alignment agent (2)
[Example 6: PSA type liquid crystal display element]
(1) Preparation of liquid crystal alignment agent (AL-6) In a solution containing 100 parts by mass of the polymer (P-1) obtained in Synthesis Example 1, 5 parts by mass of compound (Ad-4), and NMP and butyl cellosolve as solvents. (BC) was added to prepare a solution having a solvent composition of NMP / BC = 50/50 (mass ratio) and a solid content concentration of 4.0% by mass. A liquid crystal alignment agent (AL-6) was prepared by filtering this solution with a filter having a pore size of 0.2 μm.

(2) Evaluation of film adhesion The liquid crystal alignment agent (AL-6) prepared above was used for evaluation in the same manner as in "(3) Film adhesion evaluation" of Example 1. As a result, in this example, the adhesion was 189 N / cm ² , which was evaluated as "good (◯)".

(3) Evaluation of film adhesion after high-temperature baking The liquid crystal alignment agent (AL-6) prepared in (1) above is applied on a glass substrate using a spinner, and pre-baked on a hot plate at 80 ° C. for 2 minutes. After that, the inside of the refrigerator was heated (post-baked) in a nitrogen-substituted oven at 300 ° C. for 30 minutes to form a coating film having an average film thickness of 0.10 μm. By repeating the same operation, two glass substrates on which the coating film was formed were produced. An ODF sealant (S-WB42 manufactured by Sekisui Chemical Co., Ltd.) is applied on the coating film of one glass substrate on which the coating film is formed so that the width is 1 mm, and the coating film of the other glass substrate and the ODF seal are applied. The agents were bonded so that they would come into contact with each other. Then, after irradiating with light of 30,000 J / m ² (365 nm conversion) using a metal halide lamp, it was heated in an oven at 120 ° C. for 1 hour. Then, the adhesion of the film to the substrate was evaluated by measuring the adhesion force using a tensile compression tester (model number: SDWS-0201-100SL) manufactured by Imada Seisakusho. The evaluation was "especially good (◎)" when the adhesion was 175 N / cm ² or more, "good (○)" when the adhesion was 160 N / cm ² or more and less than 175 N / cm ² , and 150 N / cm ² . When it was less than 160 N / cm ² , it was regarded as "possible (Δ)", and when it was less than 150 N / cm ² , it was regarded as "defective (x)". As a result, in this example, the adhesion was 190 N / cm ² , and the adhesion was evaluated as "particularly good (⊚)".

(4) Manufacture of PSA-type liquid crystal display element A PSA-type liquid crystal display element is manufactured in the same manner as in Example 1 except that a liquid crystal alignment agent (AL-6) is used, and the liquid crystal orientation and voltage retention are evaluated. rice field. As a result, in this example, the liquid crystal orientation was evaluated as "A" and the voltage retention rate was evaluated as "S".

[Examples 7, 8, 10, 11 and Comparative Examples 2, 3]
A liquid crystal alignment agent was prepared with the same solvent composition and solid content concentration as in Example 6 except that the compounding composition was changed as shown in Table 5. Further, using each liquid crystal alignment agent, the adhesion of the film was evaluated in the same manner as in Example 6, and the PSA type liquid crystal display element was manufactured to evaluate the liquid crystal orientation and the voltage retention rate. The results are shown in Table 5. In Table 5, "-" indicates that the compound was not used.

[Example 9: Optical vertical liquid crystal display element]
A liquid crystal alignment agent (AL-9) was prepared with the same solvent composition and solid content concentration as in Example 6 except that the compounding composition was changed as shown in Table 5. Further, the adhesion of the film was evaluated in the same manner as in Example 6 using the liquid crystal alignment agent (AL-9). Further, an optical vertical liquid crystal display element was manufactured in the same manner as in Example 4 using a liquid crystal alignment agent (AL-9), and the liquid crystal orientation and voltage retention were evaluated. As a result, in this example, the liquid crystal orientation and the voltage retention rate were evaluated as "A".

As shown in Table 5, Examples 6 to 11 containing the compound (Ad-4) have better film adhesion and film adhesion after high temperature baking as compared with Comparative Example 2 not containing the cross-linking agent. It was good. Further, in Examples 6 to 11, the liquid crystal orientation and the voltage retention rate were also evaluated as "S" or "A", which were good.

On the other hand, in Comparative Example 3 in which another cross-linking agent (Ad-12) was used instead of the compound (Ad-4), the adhesion of the film was good when the post-bake temperature was 230 ° C. The adhesion of the film when the post-bake temperature was as high as 300 ° C. was evaluated as poor. Further, Comparative Example 3 was also inferior to Examples 6 to 11 in terms of voltage holding ratio.

7. Preparation and evaluation of liquid crystal alignment agent (3)
[Example 12: PSA type liquid crystal display element]
(1) Preparation of liquid crystal alignment agent (AL-12) In a solution containing 100 parts by mass of the polymer (P-1) obtained in Synthesis Example 1, 5 parts by mass of compound (Ad-5), and NMP and butyl cellosolve as solvents. (BC) was added to prepare a solution having a solvent composition of NMP / BC = 50/50 (mass ratio) and a solid content concentration of 4.0% by mass. A liquid crystal alignment agent (AL-12) was prepared by filtering this solution with a filter having a pore size of 0.2 μm.

(2) Evaluation of film adhesion Using the liquid crystal alignment agent (AL-12) prepared above, the film adhesion was evaluated in the same manner as in "(3) Film adhesion evaluation" of Example 1. As a result, in this example, the adhesion was 191 N / cm ² , which was evaluated as “good (◯)”.
(3) Manufacture and evaluation of PSA-type liquid crystal display element A PSA-type liquid crystal display element is manufactured in the same manner as in Example 1 except that a liquid crystal alignment agent (AL-12) is used, and evaluation of liquid crystal orientation and voltage retention is performed. Was done. As a result, in this example, the liquid crystal orientation was evaluated as "A" and the voltage retention rate was evaluated as "S".

(4) Evaluation of high temperature and high humidity resistance A PSA type liquid crystal display element manufactured at a post-bake temperature of 230 ° C. is stored in an oven set at 60 ° C. and a humidity of 90% for 300 hours, and then voltage is maintained in the same manner as above. The rate was measured. Let this value be VHR2, and let VHR1 be the voltage retention rate measured before storage under high temperature and high humidity conditions of 60 ° C. and 90% humidity. Was evaluated for high temperature and high humidity resistance. When ΔVHR is less than 5%, it is "especially good (◎)", when it is 5% or more and less than 10%, it is "good (○)", and when it is 10% or more and less than 20%, it is "possible (OK)". Δ) ”and 20% or more were regarded as“ defective (×) ”. As a result, in this example, it was "particularly good (⊚)".

[Examples 13, 14, 16, 17]
A liquid crystal alignment agent was prepared with the same solvent composition and solid content concentration as in Example 12 except that the compounding composition was changed as shown in Table 6. Further, using each liquid crystal alignment agent, the adhesion of the film is evaluated in the same manner as in Example 12, and a PSA type liquid crystal display element is manufactured to have liquid crystal orientation, voltage retention, and high temperature and high humidity resistance. Evaluation was performed. The results are shown in Table 6. In Table 6, "-" indicates that the compound was not used.

[Comparative Example 4]
A liquid crystal alignment agent having the same solvent composition and solid content concentration as in Example 12 except that the polymer (P-1) was changed to the polymer (P-15) and the compound (Ad-5) was not blended. (AR-6) was prepared. Further, using the prepared liquid crystal alignment agent, the adhesion of the film is evaluated in the same manner as in Example 12, and a PSA type liquid crystal display element is manufactured to have liquid crystal orientation, voltage retention and high temperature and high humidity resistance. Evaluation was performed. The results are shown in Table 6.

[Example 15: Optical vertical liquid crystal display element]
A liquid crystal alignment agent (AL-15) was prepared with the same solvent composition and solid content concentration as in Example 12 except that the compounding composition was changed as shown in Table 6. Further, the adhesion of the film was evaluated in the same manner as in Example 12 using the liquid crystal alignment agent (AL-15). Further, an optical vertical liquid crystal display element was manufactured using a liquid crystal alignment agent (AL-15) in the same manner as in Example 4, and the liquid crystal orientation, voltage retention rate, and high temperature and high humidity resistance were evaluated. As a result, in this example, the liquid crystal orientation was evaluated as "A" and the voltage retention rate was evaluated as "S". The evaluation of high temperature and high humidity resistance was "◎".

[Example 18: FFS type liquid crystal display element]
(1) Preparation of liquid crystal alignment agent and evaluation of film adhesion The liquid crystal alignment agent (AL-18) was prepared with the same solvent composition and solid content concentration as in Example 12 except that the compounding composition was changed as shown in Table 6. Prepared. In addition, the adhesion of the film was evaluated in the same manner as in Example 12 using the liquid crystal alignment agent (AL-18). The results are shown in Table 6.

(2) Manufacture of FFS type liquid crystal display element On each surface of a glass substrate in which a flat plate electrode, an insulating layer and a comb-shaped electrode are laminated on one side in this order, and a facing glass substrate on which no electrode is provided. The liquid crystal alignment agent (AL-18) prepared above was applied using a spinner and prebaked on a hot plate at 80 ° C. for 1 minute. Then, the inside of the oven was heated at 230 ° C. for 1 hour in a nitrogen-substituted oven to form a coating film having a film thickness of 0.1 μm. This coating film was subjected to a rubbing treatment using a rubbing machine having a roll wrapped with a nylon cloth at a roll rotation speed of 1000 rpm, a stage moving speed of 2.5 cm / sec, and a fluff pushing length of 0.4 mm. Then, it was ultrasonically washed in ultrapure water for 1 minute and then dried in a 100 ° C. clean oven for 10 minutes to obtain a substrate having a liquid crystal alignment film. By repeating this series of operations, a pair (two sheets) of substrates having a liquid crystal alignment film were produced.
An epoxy resin adhesive containing aluminum oxide spheres having a diameter of 3.5 μm is applied to the outer periphery of the surface of one of the above substrates having a liquid crystal alignment film by screen printing, and then the respective liquid crystal alignment film surfaces are laminated so as to face each other. They were crimped together and the adhesive was cured. Next, from the liquid crystal injection port, a nematic liquid crystal (MLC-6221) manufactured by Merck Co., Ltd. is filled between the pair of substrates, and then the liquid crystal injection port is sealed with an acrylic photocurable adhesive to polarize both sides of the outer side of the substrate. An FFS type liquid crystal display element was manufactured by laminating the plates.

(3) Evaluation of liquid crystal orientation, voltage retention and high temperature and high humidity resistance The FFS type liquid crystal display element manufactured in (2) above has the same liquid crystal orientation, voltage retention and high temperature and high humidity resistance as in Example 12. Was evaluated. As a result, in this example, the liquid crystal orientation was evaluated as "A" and the voltage retention rate was evaluated as "S". The evaluation of high temperature and high humidity resistance was "◎".

[Reference Examples 1B and 2B]
As an additive, compound (Ad-12) or compound (Ad-13) was used instead of compound [A], and the same solvent composition and solid content as in Example 12 except that the compounding composition was changed as shown in Table 6. Liquid crystal alignment agents (AR-7) and (AR-8) were prepared at different concentrations. Further, using each liquid crystal alignment agent, the adhesion of the film is evaluated in the same manner as in Example 12, and the PSA type liquid crystal display element is manufactured to evaluate the liquid crystal orientation, the voltage retention rate, and the high temperature and high humidity resistance. gone. The results are shown in Table 6.

As shown in Table 6, Examples 12 to 16 containing the compound (Ad-5) or (Ad-7) had better film adhesion and higher temperature and humidity than Comparative Example 4 in which no cross-linking agent was added. The resistance was good. Further, in Examples 12 to 16, the liquid crystal orientation and the voltage holding ratio were also evaluated as “S” or “A”, which were good.

In Reference Examples 1B and 2B in which another cross-linking agent (Ad-12) or (Ad-13) was used instead of the compounds (Ad-5) and (Ad-7), the film adhesion was good. However, the high temperature and high humidity resistance of the liquid crystal element was poor. Further, Reference Examples 1B and 2B were also inferior to Examples 12 to 16 in terms of voltage holding ratio.

8. Preparation and evaluation of liquid crystal alignment agent (4)
[Example 19: PSA type liquid crystal display element]
(1) Preparation of liquid crystal alignment agent (AL-19) In a solution containing 100 parts by mass of the polymer (P-1) obtained in Synthesis Example 1, 5 parts by mass of compound (Ad-6), and NMP and butyl cellosolve as solvents (BC) was added to prepare a solution having a solvent composition of NMP / BC = 50/50 (mass ratio) and a solid content concentration of 4.0% by mass. A liquid crystal alignment agent (AL-19) was prepared by filtering this solution with a filter having a pore size of 0.2 μm.

(2) Evaluation of film adhesion (seal width 1 mm)
Using the liquid crystal alignment agent (AL-19) prepared above, evaluation was performed in the same manner as in "(3) Evaluation of film adhesion" in Example 1. As a result, in this example, the adhesion was 189 N / cm ² , which was evaluated as "good (◯)".

(3) Evaluation of film adhesion (seal width 0.5 mm)
Examples except that the liquid crystal alignment agent (AL-19) prepared above was used and the seal width was changed from 1 mm to 0.5 mm in "(3) Evaluation of film adhesion" of Example 1. The adhesion of the film was evaluated in the same manner as in (3) of 1. The evaluation was "especially good (◎)" when the adhesion was 175 N / cm ² or more, "good (○)" when the adhesion was 160 N / cm ² or more and less than 175 N / cm ² , and 150 N / cm ² . When it was less than 160 N / cm ² , it was regarded as “possible (Δ)”, and when it was less than 150 N / cm ² , it was regarded as “defective (×)”. As a result, in this example, the adhesion was 185 N / cm ² , which was evaluated as "particularly good (⊚)".

(4) Manufacture of PSA-type liquid crystal display element A PSA-type liquid crystal display element is manufactured in the same manner as in Example 1 except that a liquid crystal alignment agent (AL-19) is used, and the liquid crystal orientation and voltage retention are evaluated. rice field. As a result, in this example, the liquid crystal orientation was evaluated as "A" and the voltage retention rate was evaluated as "S".

[Examples 20, 21, 23 to 25, 27 and Comparative Examples 5 to 8]
A liquid crystal alignment agent was prepared with the same solvent composition and solid content concentration as in Example 17 except that the compounding composition was changed as shown in Table 7. Further, using each liquid crystal alignment agent, the adhesion of the film was evaluated in the same manner as in Example 19, and the PSA type liquid crystal display element was manufactured to evaluate the liquid crystal orientation and the voltage retention rate. The results are shown in Table 7. In Table 7, "-" indicates that the compound was not used.

[Example 22: Optical vertical liquid crystal display element]
A liquid crystal alignment agent (AL-22) was prepared with the same solvent composition and solid content concentration as in Example 19 except that the compounding composition was changed as shown in Table 7. Further, the adhesion of the film was evaluated in the same manner as in Example 19 using the liquid crystal alignment agent (AL-22). Further, an optical vertical liquid crystal display element was manufactured in the same manner as in Example 5 using a liquid crystal alignment agent (AL-22), and the liquid crystal orientation and voltage retention were evaluated. The liquid crystal orientation of the liquid crystal display element was evaluated as "good", and the voltage retention rate was evaluated as "good".

[Example 26: FFS type liquid crystal display element]
(1) Preparation of liquid crystal alignment agent and evaluation of film adhesion A liquid crystal alignment agent (AL-26) was prepared with the same solvent composition and solid content concentration as in Example 19 except that the compounding composition was changed as shown in Table 7. .. Further, the adhesion of the film was evaluated in the same manner as in Example 19 using the liquid crystal alignment agent (AL-26). As a result, in this embodiment, the film adhesion evaluation when the seal width is 1 mm is “good (◯)”, and the film adhesion evaluation when the seal width is 0.5 mm is “especially good”. (◎) ”.

(2) Evaluation of Liquid Crystal Orientation An FFS type liquid crystal display element was manufactured in the same manner as in Example 18 using a liquid crystal alignment agent (AL-26), and the liquid crystal orientation was evaluated in the same manner as in Example 1 above. As a result, in this example, the liquid crystal orientation was "A".
(3) Evaluation of Voltage Retention Rate (VHR) An FFS type liquid crystal display element was manufactured in the same manner as in Example 18 using a liquid crystal alignment agent (AL-26), and the voltage retention rate was the same as in Example 1 above. Evaluation was performed. As a result, in this embodiment, the voltage holding ratio was evaluated as "S".

As shown in Table 7, Examples 19 to 27 containing the compounds (Ad-6) and (Ad-8) to (Ad-10) have a seal width as compared with Comparative Example 5 in which the cross-linking agent was not added. The adhesion of the film was good even when the thickness was narrowed to 0.5 mm. Further, in Examples 19 to 27, the liquid crystal orientation and the voltage holding ratio were also evaluated as “S” or “A”, which were good.
In contrast, comparison using other cross-linking agents (Ad-12), (A-13) or (Ad-14) in place of the compounds (Ad-6), (Ad-8) to (Ad-10). In Examples 6 to 8, when the seal width was narrowed, the adhesion of the film was not sufficient, and it was evaluated as defective. Further, Comparative Examples 6 to 8 were also inferior to Examples 19 to 27 in terms of voltage holding ratio.

Claims (9)

A liquid crystal display orientation containing a polymer component and a compound [A] which is at least one selected from the group consisting of a compound represented by the following formula (1) and a compound represented by the following formula (2). Agent.

(In the formula (1), Y ¹ and Y ² are independently hydrogen atoms or monovalent organic groups. X ¹ and X ² are independently hydroxyl groups and having 1 to 4 carbon atoms, respectively. It is an alkyl group or an alkoxy group having 1 to 4 carbon atoms. A1 and a2 are independently integers of 1 to 3, and b1 and b2 are independently integers of 0 to 3. However, 1 ≦ a1 + b1 ≦ 5 and 1 ≦ a2 + b2 ≦ 5 are satisfied. Z ¹ is a (c + d) valent organic group satisfying the following (i), (ii) or (iii).
(I) A (c + d) -valent group having 1 to 8 carbon atoms in which at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—, and at least one hydrogen of the saturated chain hydrocarbon group. A (c + d) -valent group having 1 to 8 carbon atoms or a saturated chain in which the atom is replaced with a fluorine atom and at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—. A (c + d) -valent group having 2 to 8 carbon atoms in which at least one hydrogen atom of a hydrocarbon group is substituted with a carboxyl group.
(Ii) A (c + d) -valent saturated hydrocarbon group having 11 or more carbon atoms or a (c + d) -valent aromatic hydrocarbon group having 7 or more carbon atoms.
(Iii) -S-, -SO _2- or -CO-.
c and d are independently integers of 1 to 3. However, in the case of the above (iii), c + d = 2. If more than one identical symbol is present in the equation for Y ¹ , Y ² , X ¹ and X ² , the groups of the same symbol are the same or different from each other. )

(In formula (2), Y ³ and Y ⁴ are independent hydrogen atoms or monovalent organic groups, respectively. However, at least one of Y ³ and Y ⁴ in formula (2) is It is a monovalent group represented by any of the following formulas (Y-1) to (Y-6). X ³ and X ⁴ are independently hydroxyl groups and alkyl having 1 to 4 carbon atoms, respectively. It is a group or an alkoxy group having 1 to 4 carbon atoms. A3 and a4 are independently integers of 1 to 3. b3 and b4 are independently integers of 0 to 3. , 1 ≦ a3 + b3 ≦ 5 and 1 ≦ a4 + b4 ≦ 5. Z ² is an organic group having a (e + f) valence. E and f are independently integers of 1 to ³ , respectively. If multiple identical symbols are present in the equation for Y ⁴ , X ³ and X ⁴ , the groups of the same symbol are the same or different from each other.)

(In the formulas (Y-1) to (Y-6 ^{), Ra and R b are} independently hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. “*” Is a bond. Indicates that.) The polymer component is at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, a polymer having a partial structure derived from a monomer having a polymerizable unsaturated bond, and polyorganosiloxane. The liquid crystal alignment agent according to claim 1, which comprises. The liquid crystal alignment agent according to claim 1 or 2, wherein the polymer component contains a polymer having a partial structure represented by the following formula (3).
* -L ¹ -R ¹ -R ² -R ³ -R ⁴ ... (3)
(In the formula (3), L ¹ is a single bond, -O-, -CO-, -COO- * ¹ , -OCO- * ¹ , -NR ^{25-, -NR 25 -CO-} * ¹ , -CO. -NR ^25- * ¹ , a divalent group in which the hydrogen atom of an alkanediyl group having 1 to 6 carbon atoms and an alkanediyl group having 2 to 6 carbon atoms is substituted with a hydroxyl group, -OR ^26- * ¹ , Or -R ²⁶ -O- * ¹ (where R ²⁵ is a hydrogen atom or a monovalent hydrocarbon group having 1 to 10 carbon atoms. R ²⁶ is an alkanediyl group having 1 to 3 carbon atoms. "* ¹ " indicates that it is a bond with R ^1. ) R ¹ and R ³ are independently single-bonded, substituted or unsubstituted phenylene groups, or substituted or unsubstituted, respectively. R ² is a single-bonded, substituted or unsubstituted phenylene group, substituted or unsubstituted cycloalkylene group, or -R ²⁷ -B ¹ -R ^28- (where R ²⁷ and R ²⁸ are. , Independently substituted or unsubstituted phenylene group or cycloalkylene group. B ¹ is a single bond, -O-, -COO- * ² , -OCO- * ² , -OCH _2- * ² , respectively. -CH ₂ O- * ² , or an alkanediyl group having 1 to 3 carbon atoms. "* ² " indicates that it is a bond with R ^28. ). R ⁴ is a hydrogen atom. Fluorine atom, cyano group, CH ₃ COO- * ³ (“* ³ ” indicates a bond with R ³ ), an alkyl group having 1 to 18 carbon atoms, and a fluoroalkyl group having 1 to 18 carbon atoms. A group, an alkoxy group having 1 to 18 carbon atoms, a fluoroalkoxy group having 1 to 18 carbon atoms, a hydrocarbon group having 17 to 51 carbon atoms having a steroid skeleton, or an alkyl group or a fluoroalkyl group having 1 to 18 carbon atoms. The hydrogen atom it has is a monovalent group substituted with a cyano group, where all of R ¹ , R ² and R ³ are single bonds, or the substitutions or absences of R ¹ , R ² and R ³ . When the total number of substituted phenylene groups and cycloalkylene groups is 1, ^R4 is an alkyl group having 4 to 18 carbon atoms, a fluoroalkyl group having 4 to 18 carbon atoms, an alkoxy group having 4 to 18 carbon atoms, and carbon. It is a fluoroalkoxy group having a number of 4 to 18 or a hydrocarbon group having a steroid skeleton and having a carbon number of 17 to 51. “*” Indicates a bond.) The polymer component is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide, and "* ⁴ -NR ¹¹ R ¹² " and "* ⁴ -NR ^13- * ⁵ ". , "* ⁴ -NR ¹⁴ -CO-NR ^15- * ⁵ ", "* ⁴ -NR ¹⁶ -CO- * ⁵ ", and "* ⁴ -COOR ¹⁷ " (however, R ¹¹ is a hydrogen atom or monovalent R ¹² is a protective group. R ¹³ to R ¹⁷ are independent hydrogen atoms or protective groups. “* ⁴ ” and “* ⁵ ” form a carbon-carbon bond. Any of claims 1 to 3, comprising a polymer having a structural unit derived from a diamine having at least one partial structure selected from the group consisting of (indicating that it is a bond with a constituent carbon atom). The liquid crystal alignment agent according to item 1. A liquid crystal alignment film formed by using the liquid crystal alignment agent according to any one of claims 1 to 4. A liquid crystal element provided with the liquid crystal alignment film according to claim 5. A step of applying the liquid crystal alignment agent according to any one of claims 1 to 4 on the respective conductive films of a pair of substrates having a conductive film to form a coating film.
A step of constructing a liquid crystal cell by arranging a pair of substrates coated with the liquid crystal alignment agent so that the coating films face each other with the liquid crystal layer interposed therebetween.
A step of irradiating the liquid crystal cell with light while a voltage is applied between the conductive films,
A method for manufacturing a liquid crystal element, including. A compound represented by the following formula (1).

(In the formula (1), Y ¹ and Y ² are independently hydrogen atoms or monovalent organic groups. X ¹ and X ² are independently hydroxyl groups and having 1 to 4 carbon atoms, respectively. It is an alkyl group or an alkoxy group having 1 to 4 carbon atoms. A1 and a2 are independently integers of 1 to 3, and b1 and b2 are independently integers of 0 to 3. However, 1 ≦ a1 + b1 ≦ 5 and 1 ≦ a2 + b2 ≦ 5 are satisfied. Z ¹ has a (c + d) valence of 2 to 8 carbon atoms in which at least one hydrogen atom of the saturated chain hydrocarbon group is substituted with a carboxyl group. At least one hydrogen atom of the saturated chain hydrocarbon group is replaced with a fluorine atom, and at least one methylene group of the saturated chain hydrocarbon group is replaced with —O—. It is a group of (c + d) valences having 1 to 8 carbon atoms. C and d are independently integers of 1 to 3. The same for Y ¹ , Y ² , X ¹ and X ² . If more than one symbol is present in the formula, the groups of the same symbol are the same or different from each other.) A compound represented by the following formula (2).

(In formula (2), Y ³ and Y ⁴ are independent hydrogen atoms or monovalent organic groups, respectively. However, at least one of Y ³ and Y ⁴ in formula (2) is It is a monovalent group represented by any of the following formulas (Y-3) to (Y-5). X ³ and X ⁴ are independently hydroxyl groups and alkyl having 1 to 4 carbon atoms, respectively. It is a group or an alkoxy group having 1 to 4 carbon atoms. A3 and a4 are independently integers of 1 to 3. b3 and b4 are independently integers of 0 to 3. , 1 ≦ a3 + b3 ≦ 5 and 1 ≦ a4 + b4 ≦ 5. Z ² is an organic group having a (e + f) valence. E and f are independently integers of 1 to ³ , respectively. If multiple identical symbols are present in the equation for Y ⁴ , X ³ and X ⁴ , the groups of the same symbol are the same or different from each other.)

(In formulas (Y-3) to (Y-5 ^{), Ra and R b are} independently hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. “*” Is a bond. Indicates that.)