JP6547461B2 - Liquid crystal alignment agent, liquid crystal alignment film, liquid crystal display element, retardation film, and method of producing retardation film - Google Patents

Description

  The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display device, a retardation film, and a method of manufacturing a retardation film.

  Heretofore, various liquid crystal display devices have been developed in which various driving methods having different electrode structures, physical properties of liquid crystal molecules, manufacturing processes, etc. have been developed. For example, TN type, STN type, VA type, in-plane switching type (IPS type), Various liquid crystal display elements such as FFS type are known. These liquid crystal display elements have a liquid crystal alignment film for aligning liquid crystal molecules. As a material of a liquid crystal aligning film, a polyamic acid and a polyimide are generally used from the point which various characteristics, such as heat resistance, mechanical strength, and affinity with a liquid crystal, are favorable. As a method of forming a liquid crystal aligning film on a substrate using a polyamic acid or a polyimide, for example, a solution containing a polyamic acid is applied on a substrate and heated to imidize it on the substrate to form a polyimide film. Generally, a method of applying a solution containing a soluble polyimide on a substrate and removing a solvent from the substrate to form a polyimide film is generally used.

  Moreover, in recent years, using a polyamic acid ester alone as a polymer component of a liquid crystal aligning agent, or using together with a polyamic acid or a polyimide is proposed (for example, refer patent documents 1-3).

Patent Document 1 discloses that a polyamic acid ester and a polyamic acid as a polymer component are contained in a liquid crystal aligning agent, and the weight average molecular weight of the polyamic acid ester is smaller than that of the polyamic acid. According to such a liquid crystal aligning agent, it is described in Patent Document 1 that fine irregularities generated on the film surface of the liquid crystal alignment film can be reduced, and the liquid crystal alignment and electric characteristics of the liquid crystal display element can be improved.
Patent Document 2 proposes a liquid crystal aligning agent containing a polyamic acid ester and a soluble polyimide. According to such a liquid crystal aligning agent as described in Patent Document 2, even if the imidization ratio is high, no whitening phenomenon occurs at the time of film formation, and the printability and the rubbing resistance of the film are good. It is described that the liquid crystal alignment and electrical properties can be improved.
Patent Document 3 contains, as a liquid crystal aligning agent for photoalignment treatment, at least one polymer selected from the group consisting of a polyamic acid ester having a cyclobutane ring in its main chain and its imidized polymer, and a polyamic acid. Liquid crystal alignment agents are disclosed.

  Various optical materials are used for the liquid crystal display element, and among them, the retardation film has the purpose of eliminating the coloring of the display and the purpose of eliminating the viewing angle dependency such that the display color and the contrast ratio change depending on the visual direction. Used in As such a retardation film, one having a liquid crystal alignment film formed on the surface of a substrate such as a TAC film and a liquid crystal layer formed by curing a polymerizable liquid crystal on the surface of the liquid crystal alignment film is known. ing. In addition, in the preparation of a liquid crystal alignment film in a retardation film, a photoalignment method of imparting liquid crystal alignment ability by irradiating polarized or non-polarized light to a radiation sensitive organic thin film formed on a substrate surface is used. Various liquid crystal aligning agents for retardation films for producing a liquid crystal alignment film by such a method have been proposed (see, for example, Patent Document 4).

  Further, in recent years, with the spread of mobile applications such as mobile phones, weight reduction and thickness reduction of liquid crystal display elements are required. Along with this, various attempts have been made to reduce the thickness of the substrate (see, for example, Patent Document 5).

International Publication No. 2011/115078 International Publication No. 2013/147083 International Publication No. 2011/115079 JP 2012-37868 A JP, 2012-243935, A JP, 2011-065195, A

  The inventors of the present invention have found that a liquid crystal aligning agent using a polyamic acid ester as a polymer component tends to cause warpage in the substrate due to film contraction when a coating film is formed on a thin substrate. Such warping of the substrate may cause a reduction in the product yield and a deterioration in the quality of the liquid crystal panel. In order to improve the display quality of the liquid crystal display element while responding to the thinning of the substrate in recent years, it is possible to reduce the warp of the substrate without impairing the basic characteristics such as the alignment of liquid crystal molecules and the voltage holding ratio. Materials are required. Moreover, also when it uses for the use of retardation film, it is preferable that it is a material which shows favorable liquid crystal orientation.

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a liquid crystal aligning agent which can reduce the warpage of a substrate and can obtain a liquid crystal display element having good liquid crystal alignment and voltage holding ratio. I assume. Another object of the present invention is to provide a liquid crystal aligning agent capable of obtaining a retardation film having good liquid crystal alignment properties.

  The present inventors diligently studied to achieve the problems of the prior art as described above, and when the polyamic acid ester structure and the specific partial structure were combined in the polymer component, the liquid crystal alignment and electrical properties were maintained. While finding that it is possible to suppress the warping of the substrate, the present invention has been solved. Specifically, the present invention provides the following liquid crystal alignment agent, liquid crystal alignment film, liquid crystal display element, retardation film, and method for producing retardation film.

（式（１）中、Ｒ^１及びＲ^２は、それぞれ独立に、炭素数１〜１２のアルキル基、−Ｓｉ（Ｒ^５）_３（ただし、Ｒ^５はアルキル基又はアルコキシ基であり、複数のＲ^５は同じでも異なってもよい。）、フッ素原子を有する１価の基、（メタ）アクリロイル基を有する１価の基、又は桂皮酸構造を有する１価の基であり、Ｒ^３及びＲ^４は、それぞれ独立に、水素原子、又は置換若しくは無置換の炭素数１〜１０の１価の鎖状炭化水素基である。Ｘ^１は４価の有機基であり、Ｙ^１は２価の有機基である。） In one aspect of the present invention, the polymer component contains one or more polymers, and the polymer component has a partial structure (c-1) represented by the following formula (1) And a liquid crystal aligning agent containing at least one partial structure (c-2) selected from the group consisting of a siloxane structure and a structure derived from a monomer having a polymerizable carbon-carbon unsaturated bond.

(In formula (1), R ¹ and R ² are each independently an alkyl group having 1 to 12 carbon atoms, —Si (R ⁵ ) ₃ (provided that R ⁵ is an alkyl group or an alkoxy group, R ⁵ may be the same or different), a monovalent group having a fluorine atom, a monovalent group having a (meth) acryloyl group, or a monovalent group having a cinnamic acid structure, and R ³ and R ⁴ each independently represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon hydrocarbon group having 1 to 10 carbon atoms X ¹ is a tetravalent organic group, and Y ¹ is a divalent It is an organic group.)

  The present invention provides, in another aspect, a liquid crystal alignment film formed using the liquid crystal alignment agent described above. Moreover, in another one side, the liquid crystal display element and retardation film which comprise the said liquid crystal aligning film are provided. Further, the step of applying the liquid crystal aligning agent as described above onto a substrate to form a coating, the step of irradiating the coating with light, and the step of applying and curing a polymerizable liquid crystal on the coating after light irradiation And providing a process for producing a retardation film.

  According to the liquid crystal aligning agent of the present invention, it is possible to obtain a liquid crystal display device capable of reducing the warpage of the substrate and having good liquid crystal alignment and voltage holding ratio. In addition, a retardation film having good liquid crystal alignment can be obtained.

Hereinafter, each component contained in the liquid crystal aligning film of this invention, and the component contained as needed are demonstrated.
<Polymer component>
The liquid crystal aligning agent of the present invention contains one or more polymers as a polymer component, and in the polymer component, a partial structure (c-1) represented by the above formula (1) and a siloxane And at least one partial structure (c-2) selected from the group consisting of a structure and a structure derived from a monomer having a polymerizable carbon-carbon unsaturated bond.

[Partial structure (c-1)]
In the partial structure (c-1), R ¹ and R ^{2 in} the above formula (1) are each an alkyl group having 1 to 12 carbon atoms, -Si (R ⁵ ) ₃ (wherein R ⁵ is an alkyl group or an alkoxy group) And a plurality of R ^{5 s} may be the same or different), a monovalent group having a fluorine atom, a monovalent group having a (meth) acryloyl group, or a monovalent group having a cinnamic acid structure.
Here, examples of the alkyl group having 1 to 12 carbon atoms include methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, and dodecyl group. And the like, which may be linear or branched. The alkyl group in R ¹ and R ² preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, and still more preferably a methyl group or an ethyl group, from the viewpoint of vaporizing a compound generated by post-baking during film formation. It is.

In the group "-Si ^(R _{5) 3",} alkyl group and alkoxy group for ^{R 5} preferably has 1 to 5 carbon atoms, 1 to 3 carbon atoms is more preferred.
As a monovalent group which has the said fluorine atom, a fluoroalkyl group, a fluoroalkoxy group, a fluoroalkyl ester group etc. are mentioned, for example, Preferably it is a fluoroalkyl group. The fluorinated alkyl group preferably has 1 to 5 carbon atoms, and more preferably 1 to 3 carbon atoms.
Examples of the monovalent group having a (meth) acryloyl groups, for example ^"-R 6 -A ^3" (wherein, ^{R 6} is a divalent organic group, ^{A 3} is (meth) acryloyl group.) And the like. The divalent organic group R ^6, for example _{-CH 2 -CH 2 -O - *,} - CH 2 -CH 2 -NH - *, - CH (CH 3) -CH 2 -O- *, and - _{CH (CH 3) -CH 2 -NH} - * (. which although a bond marked with "*" is bonded to ^{a 3)} can be mentioned as preferable specific examples. In addition, "(meth) acryloyl" is a meaning including acryloyl and methacryloyl.

（式（ｘ−１）及び式（ｘ−２）中、Ｒ^１１及びＲ^１４は、それぞれ独立に、水素原子、フッ素原子、炭素数１〜２０のアルキル基又は炭素数１〜２０のフルオロアルキル基である。Ｘ^１１、Ｘ^１２及びＸ^１３は、それぞれ独立に、単結合、酸素原子、硫黄原子、＊−ＣＯＯ−又は＊−ＯＣＯ−（ただし、「＊」を付した結合手がそれぞれＲ^１１、Ｒ^１２又はＲ^１４と結合する。）である。Ｒ^１２及びＲ^１５は、それぞれ独立に、１，４−フェニレン基又は１，４−シクロヘキシレン基である。Ｘ^１４は、単結合、炭素数１〜３のアルカンジイル基、酸素原子、硫黄原子又は−ＮＨ−である。Ｘ^１５は酸素原子、＊−ＣＯＯ−又は＊−ＯＣＯ−（ただし、「＊」を付した結合手がＲ^１６と結合する。）である。Ｒ^１６は２価の芳香族基、２価の脂環式基、２価の複素環式基又は２価の縮合環式基である。Ｒ^１７は単結合、＊−ＯＣＯ−（ＣＨ_２）_ｈ−又は＊−Ｏ−（ＣＨ_２）_ｉ−（ただし、「＊」を付した結合手がＲ^１６と結合し、ｈ及びｉはそれぞれ１〜１０の整数である。）である。Ｘ^１６は＊−ＣＯＯ−又は＊−ＯＣＯ−（ただし、「＊」を付した結合手がＲ^１７と結合する。）である。Ｒ^１３及びＲ^１８は、それぞれ独立にフッ素原子、シアノ基又はメチル基である。ａ、ｅ及びｄはそれぞれ独立に０〜３の整数であり、ｂ及びｆはそれぞれ独立に１〜１０の整数であり、ｃ及びｇはそれぞれ独立に０〜４の整数である。） The monovalent group having a cinnamic acid structure may be a monovalent group containing cinnamic acid or a derivative thereof as a basic skeleton, and the remaining structure is not particularly limited. As preferable specific examples, for example, a group represented by the following formula (x-1) and a group represented by the following formula (x-2) can be mentioned.

(In Formula (x-1) and Formula (x-2), R ¹¹ and R ¹⁴ each independently represent a hydrogen atom, a fluorine atom, an alkyl group having 1 to 20 carbon atoms, or a fluoroalkyl having 1 to 20 carbon atoms X ¹¹ , X ¹² and X ¹³ each independently represent a single bond, an oxygen atom, a sulfur atom, * -COO- or * -OCO- (wherein the bond with “*” is R ¹¹ binds to ^{R 12} or ^{R 14.)} a is ^{.R 12} and ^{R 15} are each independently a 1,4-phenylene group or a 1,4-cyclohexylene group ^{.X 14} is a single bond, alkanediyl group having 1 to 3 carbon atoms, an oxygen atom, a sulfur atom or -NH- in which ^{.X 15} is an oxygen atom, * - COO- or * -OCO- (where bond marked with "*" is R ¹⁶ binds to.) in which ^{.R 16} is a divalent aromatic Group, a divalent alicyclic group, a divalent heterocyclic group or a divalent fused cyclic group, R ¹⁷ is a single bond, * -OCO- (CH ₂ ) _h -or * -O- (CH ₂ ) _i — (wherein the bond attached with “*” is bonded to R ¹⁶ and h and i are each an integer of 1 to 10.) X ¹⁶ is * -COO- or * R ¹³ and R ¹⁸ each independently represent a fluorine atom, a cyano group or a methyl group, a, e and -OCO- (wherein the bond attached with “*” is bonded to R ¹⁷ ). d is each independently an integer of 0 to 3, b and f are each independently an integer of 1 to 10, and c and g are each independently an integer of 0 to 4.)

（式中、Ｒ^１１及びｂは、上記式（ｘ−１）中のＲ^１１及びｂと同義である。）

（式中、Ｒ^１４及びｆは、上記式（ｘ−２）中のＲ^１４及びｆと同義である。） Preferable specific examples of the monovalent group having a cinnamic acid structure include, as a group represented by the above formula (x-1), for example, the following formula (x-1-1) to the formula (x-1-11) As a group represented by the above formula (x-2), for example, a compound represented by each of the following formula (x-2-1) to the formula (x-2-3) Besides, the groups described in JP 2011-133825 A can be mentioned.

^{(Wherein, R 11} and b are as defined and ^{R 11} and b in the formula (x-1).)

^{(Wherein, R 14} and f have the same meanings as ^{R 14} and f in the formula (x-2).)

As R ¹ and R ^{2 in} the above-mentioned formula (1), from the viewpoint of suppressing the deterioration in quality due to the compound (impurity) derived from R ¹ and R ² remaining in the film and from the viewpoint of storage stability Among them, an alkyl group having 1 to 5 carbon atoms is preferable, and an alkyl group having 1 to 3 carbon atoms is more preferable. R ¹ and R ² may be the same or different between the partial structures.

R ³ and R ⁴ are a hydrogen atom or a substituted or unsubstituted C 1-10 monovalent chain hydrocarbon group. The monovalent chain hydrocarbon group in R ³ and R ⁴ may be saturated or unsaturated. Specifically, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, etc. may be mentioned, and these may be linear or branched. It is also good. As a substituent which the monovalent | monohydric chain hydrocarbon group of R ³ and R ⁴ may have, for example, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom etc.), a hydroxyl group, a cyano group, an alkoxy And the like.
Among these, a hydrogen atom or an alkyl group having 1 to 5 carbon atoms is preferable among R ³ and R ⁴ , and a hydrogen atom, a methyl group or an ethyl group is more preferable.

In the above formula (1), X ¹ is, for example, a tetravalent group derived from tetracarboxylic acid dianhydride, that is, a residue obtained by removing two acid anhydride groups from tetracarboxylic acid dianhydride, ¹ is, for example, a divalent group derived from diamine, that is, a residue obtained by removing two primary amino groups from diamine. As an example of an organic group in X ¹ and Y ¹ , for example, a hydrocarbon group, a methylene group of a hydrocarbon group is —O—, —COO—, —CO—, —NHCO—, —S—, —NH—, A group which is substituted by a functional group such as -SO _2- , a group having a heterocycle, and the like. In each of these groups, a hydrogen atom bonded to a carbon atom is substituted by, for example, a halogen atom, a hydroxyl group, a nitro group, an amino group, a carboxyl group, a thiol group, an alkylsilyl group, an alkoxysilyl group, an alkoxy group, etc. It is also good.

  Here, in the present specification, the term "hydrocarbon group" is meant to include a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group. "Chain chain hydrocarbon group" means a hydrocarbon group composed of only a chain structure, which does not contain a cyclic structure in the main chain. However, the chain structure may be linear or branched. The "alicyclic hydrocarbon group" means a hydrocarbon group containing only an alicyclic hydrocarbon structure as a ring structure and not including an aromatic ring structure. However, it does not need to be comprised only with the structure of alicyclic hydrocarbon, and the thing which has chain structure in the part is also included. Also, "aromatic hydrocarbon group" means a hydrocarbon group containing an aromatic ring structure as a ring structure. However, it is not necessary to be composed only of an aromatic ring structure, and a chain structure or a structure of alicyclic hydrocarbon may be included in part thereof. The "organic group" means a group containing a carbon atom, and may contain a hetero atom in the structure.

Examples of X ¹ include tetravalent groups derived from aliphatic tetracarboxylic acid dianhydrides, alicyclic tetracarboxylic acid dianhydrides or aromatic tetracarboxylic acid dianhydrides. Among them, a tetravalent group having a partial structure formed by removing two acid anhydride groups possessed by one compound selected from the group consisting of alicyclic tetracarboxylic acid dianhydride and aromatic tetracarboxylic acid dianhydride. Is preferred. From the viewpoint of liquid crystal alignment and solubility in solvents, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid 2: 3,5: 6-dianhydride is particularly preferable. 2,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 5- (2,5-dioxotetrahydrofuran-3-yl) -8-methyl-3a 1,4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, 5- (2,5-dioxotetrahydrofuran-3-yl) -3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic acid 2: 4,6: 8-dianhydride, 1, 2,4,5-cyclohexanetetracarboxylic acid It has a partial structure formed by removing two acid anhydride groups possessed by one compound selected from the group consisting of an anhydride and pyromellitic dianhydride (hereinafter, also referred to as "specific acid dianhydride"). It is a tetravalent group.
Examples of Y ¹ include divalent diamines derived from aliphatic diamines, alicyclic diamines, aromatic diamines or diaminoorganosiloxanes. Among them, a partial structure derived from an aromatic diamine is preferable from the viewpoint of liquid crystal alignment and electrical properties. A specific example of the diamine constituting the Y ^1, can be applied to the description of exemplified diamines below.

（式（ｃ−２−１）中、Ｒ^８は、水素原子、水酸基又は１価の有機基であり、分子内又は分子間で他の基と相互作用していてもよい。式中の２つのＲ^８は、同じでも異なっていてもよい。） [Partial structure (c-2)]
The siloxane structure in partial structure (c-2) has a siloxane bond (Si-O) in the backbone. For example, it is represented by the following formula (c-2-1).

(In the formula (c-2-1), R ⁸ represents a hydrogen atom, a hydroxyl group or a monovalent organic group, and may interact with other groups within or between molecules. 2 in the formula R ⁸ may be the same or different.)

Examples of the monovalent organic group of R ^{8 in} the above formula (c-2-1) include a hydroxyl group, an alkoxy group, a monovalent hydrocarbon group, and a methylene group of a monovalent hydrocarbon group as —O— and —COO. Groups obtained by substitution with functional groups such as-, -CO-, -NHCO-, -S-, -NH-, -SO _2- and the like, and groups having a heterocyclic ring, etc. The hydrogen atom to be bound is substituted, for example, by a halogen atom, a hydroxyl group, a nitro group, an amino group, a carboxyl group, a thiol group, an epoxy group, an alkylsilyl group, an alkoxysilyl group, an alkoxy group, a (meth) acryloyl group, a ureido group, etc. It may be As a specific example when R ⁸ in the above formula (c-2-1) interacts with another group in a molecule or between molecules, a covalent bond with another group in a molecule or between molecules is exemplified. Mode of formation or intermolecular force weaker than covalent bond (eg, ion-dipole interaction, dipole-dipole interaction, hydrogen bond, van der Waals force, etc.) And the like.

  Examples of the monomer having a polymerizable carbon-carbon unsaturated bond (hereinafter, also referred to as “polymerizable unsaturated compound”) include (meth) acrylic compounds, aromatic vinyl compounds, maleimide compounds, olefin hydrocarbons and the like. It can be mentioned. Among the polymerizable unsaturated compounds, at least one selected from the group consisting of (meth) acrylic compounds, aromatic vinyl compounds and maleimide compounds is preferable. The structure derived from the polymerizable unsaturated compound contained in the polymer component may be only one type or two or more types. In the present specification, "(meth) acrylic" is meant to include acrylic and methacrylic.

In the polymer component of the liquid crystal aligning agent, the partial structure (c-1) and the partial structure (c-2) may be present in the same molecule or may be present in different molecules. Specifically, an embodiment containing a polymer having a partial structure (c-1) and a partial structure (c-2); a polymer (A) having a partial structure (c-1), and a partial structure (c) The aspect etc. which contain the polymer (B) which has 2), etc. are mentioned. When the polymer (A) and the polymer (B) are contained, these two polymers may be present independently of each other in the liquid crystal aligning agent, or they may be the same or different heavy. At least a part of the combination may interact between molecules in the liquid crystal alignment agent after compounding. The "interaction" means to form a covalent bond between molecules or to form an intermolecular force weaker than the covalent bond.
The liquid crystal aligning agent of the present invention is an embodiment in which the partial structure (c-1) and the partial structure (c-2) are present in different molecules, that is, the polymer (A) having the partial structure (c-1) And a polymer (B) having a partial structure (c-2).

<Polymer (A)>
The polymer (A) can be obtained according to the usual method of organic chemistry. Specifically, for example, a method in which a polyamic acid is synthesized by reacting [1] tetracarboxylic acid dianhydride with a diamine, and then reacting the obtained polyamic acid with an esterification agent, [2] tetracarboxylic acid Method of reacting acid diester and diamine, method of reacting [3] tetracarboxylic acid diester dihalide and diamine, reaction of [4] tetracarboxylic acid dianhydride, diamine and esterifying agent in an organic solvent Methods, etc.

· Method [1] (tetracarboxylic acid dianhydride)
Examples of the tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid include aliphatic tetracarboxylic acid dianhydride, alicyclic tetracarboxylic acid dianhydride, and aromatic tetracarboxylic acid dianhydride. it can. Specific examples thereof include aliphatic tetracarboxylic acid dianhydrides such as butane tetracarboxylic acid dianhydride;
As alicyclic tetracarboxylic acid dianhydride, for example, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 5- (2,5-dicarboxylic acid dianhydride, etc. Oxotetrahydrofuran-3-yl) -8-methyl-3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, 5- (2,5-dioxotetrahydrofuran-3-) Yl) -3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro -3 '-(tetrahydrofuran-2', 5'-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3 , 5, 6- Carboxy-2-carboxymethyl norbornane-2: 3,5: 6-dianhydride, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic acid 2: 4,6: 8-di Anhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid 2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1 .0 ^2,6 ] Undecane-3,5,8,10-tetraone, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, bicyclo [2.2.2] oct-7-ene-2, 3,5,6-tetracarboxylic acid dianhydride etc .;
Examples of the aromatic tetracarboxylic acid dianhydride include, for example, pyromellitic acid dianhydride and the like, and besides, tetracarboxylic acid dianhydride described in JP-A-2010-97188 can be used. In addition, as tetracarboxylic acid dianhydride used for the synthesis | combination of a polyamic acid, these 1 type can be used individually or in combination of 2 or more types.

Preferred examples of the tetracarboxylic dianhydride used in the synthesis of the polyamic acid, the same compound as the particular dianhydrides exemplified by X ¹ in the formula (1). The ratio of use of this specific acid dianhydride is preferably 10 mol% or more, more preferably 20 mol% or more based on the total amount of tetracarboxylic acid dianhydride used in the synthesis of polyamic acid. Preferably, it is more preferably 30 mol% or more. The tetracarboxylic acid dianhydride used for the synthesis of the polyamic acid can be used alone or in combination of two or more of the above-mentioned compounds.

(Diamine)
As a diamine used for the synthesis | combination of a polyamic acid, an aliphatic diamine, an alicyclic diamine, an aromatic diamine, a diamino organosiloxane etc. can be mentioned, for example. As specific examples of these, as aliphatic diamines, for example, metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1,3-bis (aminomethyl) cyclohexane and the like; As alicyclic diamines, for example, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine) and the like;

（式（Ｄ−１）中、Ｘ^I及びＸ^IIは、それぞれ独立に、単結合、−Ｏ−、−ＣＯＯ−又は−ＯＣＯ−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。）
で表される化合物などのほか、 As aromatic diamines, for example, p-phenylenediamine, 4,4'-ethylenedianiline, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,2'-dimethyl -4,4'-Diaminobiphenyl, 4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl, 4,4'-diaminodiphenyl ether, 2- (4-aminophenyl) ethylamine, bis (4 -Aminophenyl) amine, N, N-bis (4-aminophenyl) methylamine, 4,4'-diaminobenzophenone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2- Bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexaf Oropropane, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4,4'-(m-phenylenediisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4'- Bis (4-aminophenoxy) biphenyl, N, N'-bis (4-aminophenyl) -benzidine, N, N'-bis (4-aminophenyl) -N, N'-dimethylbenzidine, dodecanoxy-2,4 -Diaminobenzene, tetradecanoxy-2,4-diaminobenzene, octadecanoxy-2,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestyloxy-3,5-diaminobenzene, cholestanyloxy-2, 4-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, 3,5-diaa Cholestanyl benzoate, cholestyl 3,5-diaminobenzoate, lanostanyl 3,5-diaminobenzoate, 3,6-bis (4-aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 4- (4'-Trifluoromethoxybenzyloxy) cyclohexyl-3,5-diaminobenzoate, {4- [2- (3,5-diaminophenoxy) -ethoxy] -phenyl} -ethanone, 3,4-diamino Benzophenone, {4- [2- (3,5-diaminophenoxy) -ethoxy] -phenyl} -phenyl-methanone, {4- [2- (2,4-diaminophenoxy) -ethoxy] -phenyl} -p- Toluyl-methanone, 2,7-diaminofluorenone, 2,7-diaminofluorene, and 9,9-bis (4- Minofeniru) fluorene, and the following formula (D-1)

(In the formula (D-1), X ^I and X ^II each independently represent a single bond, -O-, -COO- or -OCO-, and R ^I is an alkanediyl group having 1 to 3 carbon atoms R ^II is a single bond or an alkanediyl group having 1 to 3 carbon atoms, a is 0 or 1, b is an integer of 0 to 2, c is an integer of 1 to 20, and d is 0 or 1. However, a and b can not simultaneously be 0.)
In addition to the compounds represented by

のそれぞれで表される化合物等の窒素含有複素環ジアミン：下記式（ｄ−４）〜式（ｄ−７）

のそれぞれで表される化合物などを； 3,5-diaminobenzoic acid, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2, 2'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-3-carboxylic acid 4,4'-diaminodiphenylmethane-3-carboxylic acid, 4,4'-diaminodiphenylethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenylethane-3-carboxylic acid, and 4,4 ' Carboxyl group-containing diamines such as diaminodiphenyl ether-3,3'-dicarboxylic acid:
2,6-Diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 1,4- Bis- (4-aminophenyl) -piperazine, the following formulas (d-1) to (d-3)

And nitrogen-containing heterocyclic diamines such as compounds represented by each of the following formulas: (d-4) to (d-7)

Compounds represented by each of

  Examples of diaminoorganosiloxanes include 1,3-bis (3-aminopropyl) -tetramethyldisiloxane, 3,3 ′-[1,4-phenylenebis (dimethylsilanediyl)] bis (1-propanamine), etc. In addition to each of them, the diamine described in JP-A-2010-97188 can be used.

The divalent group represented by "-X ^I- (R ^I- X ^II ) _d- " in the above formula (D-1) is an alkanediyl group having 1 to 3 carbon atoms, * -O-, *- COO- or _{* -O-C 2 H 4 -O-} ( where bond marked with "*" is bonded to the diamino phenyl group.) is preferably. Group _"-C c _{H 2c + 1"} is preferably linear. The two amino groups in the diaminophenyl group are preferably in the 2,4- or 3,5-position relative to the other groups.
As a specific example of a compound represented by the said Formula (D-1), the compound etc. which are represented by each of following formula (D-1-1)-a formula (D-1-4) can be mentioned, for example . These diamines can be used alone or in combination of two or more.

(Synthesis of polyamic acid)
The ratio of tetracarboxylic acid dianhydride and diamine used in the synthesis reaction of the polyamic acid is 0.2 to 2 acid anhydride groups of tetracarboxylic acid dianhydride to 1 equivalent of amino group of diamine. The ratio which becomes equivalent is preferable, and the ratio which becomes 0.3-1.2 equivalent is more preferable.

In the synthesis of the polyamic acid, an end-modified polymer may be synthesized using an appropriate molecular weight modifier together with the above-described tetracarboxylic acid dianhydride and diamine. By using such a terminal-modified polymer, the coatability (printability) of the liquid crystal aligning agent can be further improved without impairing the effects of the present invention.
Examples of molecular weight modifiers 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 phenyl isocyanate and naphthyl isocyanate. It can be mentioned. The use ratio of the molecular weight modifier is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, based on 100 parts by weight of the total of tetracarboxylic acid dianhydride and diamine used.

  The synthesis reaction of polyamic acid is preferably carried out in an organic solvent. The reaction temperature at this time is preferably -20 ° C to 150 ° C, and more preferably 0 to 100 ° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

Examples of the organic solvent used for the reaction include aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons and the like. Among these organic solvents, one or more selected from the group consisting of an aprotic polar solvent and a phenolic solvent (first group organic solvent), or one or more selected from the first group organic solvent It is preferable to use a mixture of at least one selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons (second group organic solvents). In the latter case, the use ratio of the second group organic solvent is preferably 50% by weight or less, more preferably 40% by weight, based on the total amount of the first group organic solvent and the second group organic solvent. Or less, more preferably 30% by weight or less.
Particularly preferably, N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethylsulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide, m-cresol, xylenol and halogen. It is preferable to use, as a solvent, one or more selected from the group consisting of halogenated phenols, or a mixture of one or more of these and another organic solvent in the above ratio.
The amount (a) of the organic solvent used is such that the total amount (b) of the tetracarboxylic acid dianhydride and the diamine is 0.1 to 50% by weight with respect to the total amount (a + b) of the reaction solution. Is preferred.

  As described above, a reaction solution in which the polyamic acid is dissolved is obtained. The reaction solution may be subjected to the reaction with the esterification agent as it is, or the polyamic acid contained in the reaction solution may be isolated and then subjected to the reaction with the esterification agent, or the isolated polyamic acid After being purified, it may be subjected to a reaction with an esterification agent. The isolation and purification of the polyamic acid can be carried out according to known methods.

(Reaction of polyamic acid and esterifying agent)
Examples of the esterifying agent to be reacted with the polyamic acid include alcohols, halides, acetal compounds, epoxy compounds and the like. As specific examples of these, as alcohols, for example, methanol, ethanol, propanol, butanol, pentanol, hexanol, octanol, trifluoromethanol, 2,2,2-trifluoroethanol, 2- (meth) acryloyloxyethyl alcohol 1- (Meth) acryloyloxy-2-propyl alcohol, 2- (Meth) acrylamidoethyl alcohol, 1- (Meth) acrylamido-2-propyl alcohol etc. as a halide; eg methyl bromide, ethyl bromide, Methyl chloride, ethyl chloride and the like; acetal compounds such as N, N-dimethylformamide diethyl acetal, N, N-diethyl formamide diethyl acetal and the like; epoxy compounds such as represented by the above formula (x-1) That the epoxy group-containing compound having a group, an epoxy group-containing compound having a group represented by the formula (x-2), can be exemplified respectively. Among them, alcohols can be preferably used as the esterification agent.

The reaction of the polyamic acid with the esterifying agent is preferably carried out in an organic solvent. The reaction temperature at this time may be appropriately set according to the type of the esterifying agent, but for example, in the case of alcohols, -20 ° C to 200 ° C is preferable, and 0 to 120 ° C is more preferable. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.
As the organic solvent used for the reaction, the description of the organic solvent which can be used for the synthesis of polyamic acid can be applied. Specifically, N, N-dimethylformamide, N-methyl-2-pyrrolidone, (gamma) -butyrolactone etc. can be used preferably. The amount of the organic solvent used is preferably such that the polyamic acid is 0.1 to 50% by weight with respect to the total amount of the reaction solution. The amount of the esterifying agent used is preferably 0.002 to 10 moles, and more preferably 0.02 to 6 moles with respect to 1 mole of the amic acid structural unit of the polyamic acid.

Method [2] The tetracarboxylic acid diester used in the method [2] is obtained, for example, by ring-opening the tetracarboxylic acid dianhydride exemplified above using an alcohol such as methanol, ethanol, propanol and the like. be able to. Examples of the diamine to be reacted with the tetracarboxylic acid diester include the diamines exemplified in the synthesis of the above polyamic acid. The ratio of use of the tetracarboxylic acid diester and the diamine to be subjected to the synthesis reaction of the polyamic acid ester is such that the carboxyl group of the tetracarboxylic acid diester becomes 0.2 to 2 equivalents with respect to 1 equivalent of the amino group of the diamine. Is preferable, and a ratio of 0.3 to 1.2 equivalents is more preferable.

The reaction of the tetracarboxylic acid diester with the diamine is preferably carried out in an organic solvent in the presence of a dehydration catalyst and a base. The reaction temperature at this time is preferably -20 ° C to 150 ° C, and more preferably 0 to 100 ° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.
As the organic solvent used for the reaction, the description of the organic solvent which can be used for the synthesis of polyamic acid can be applied, among which N, N-dimethylformamide, N-methyl-2-pyrrolidone, γ-butyrolactone and the like Can be preferably used. The proportion of the organic solvent used is preferably such that the total amount of the tetracarboxylic acid diester and the diamine is 0.1 to 50% by weight with respect to the total amount of the reaction solution.

As a dehydration catalyst used for the above reaction, for example, 4- (4,6-dimethoxy-1,3,5-triazin-2-yl) -4-methylmorpholinium halide, carbonylimidazole, dicyclohexylcarbodiimide, phosphorus-based condensation Agents and the like. It is preferable to set it as 2-3 mol with respect to 1 mol of tetracarboxylic-acid diesters, and, as for the use ratio of these condensing agents, it is more preferable to set it as 2-2.5 mol.
As a base, for example, tertiary amines such as pyridine and triethylamine can be preferably used. The proportion of the base used is preferably 2 to 4 moles, and more preferably 2 to 3 moles per mole of diamine. The above reaction may be carried out in the presence of a Lewis acid for the purpose of promoting the progress of the reaction. The Lewis acid includes, for example, lithium halides such as lithium chloride.

Method [3] The tetracarboxylic acid diester dihalide used in Method [3] can be obtained by reacting the tetracarboxylic acid diester obtained as described above with a suitable chlorinating agent. Examples of chlorinating agents used in the reaction include thionyl chloride, phosgene, oxazol chloride and the like.
Examples of the diamine to be reacted with the tetracarboxylic acid diester dihalide include the diamines exemplified in the synthesis of the above polyamic acid. The ratio of the tetracarboxylic acid diester dihalide to the diamine is preferably 0.2 to 2 equivalents of the halogen atom of the tetracarboxylic acid diester dihalide relative to 1 equivalent of the amino group of the diamine. A ratio of 3 to 1.2 equivalents is more preferable.

  The reaction of the tetracarboxylic acid diester dihalide with the diamine is preferably carried out in an organic solvent in the presence of a base. As a base used for the above reaction, for example, tertiary amines such as pyridine and triethylamine; sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, potassium hydroxide, sodium, alkali metals such as potassium are preferably used. it can. The proportion of the base used is preferably 2 to 4 moles, and more preferably 2 to 3 moles per mole of diamine. As an organic solvent used for reaction, description of the organic solvent which can be used for the synthesis | combination of a polyamic acid can be applied. The proportion of the organic solvent used is preferably such that the total amount of the tetracarboxylic acid diester dihalide and the diamine is 0.1 to 50% by weight with respect to the total amount of the reaction solution. The reaction temperature is preferably -30 ° C to 150 ° C, and more preferably -10 to 100 ° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

Method [4] Method [4] is preferable in the case of obtaining a silyl-based polyamic acid ester. Examples of the esterifying agent used in the synthesis of the silyl polyamic acid ester include silylamide silylating agents such as bis (trimethylsilyl) acetamide, bis (trimethylsilyl) trifluoroacetamide, and bis (trimethylsilyl) urea.
The description of the organic solvent which can be used for the synthesis of the polyamic acid can be applied as the organic solvent used for the above reaction. The reaction temperature is preferably -20 ° C to 250 ° C, and more preferably -10 to 200 ° C. The reaction time is preferably 1 to 20 hours, more preferably 2 to 15 hours. The amount of the silylating agent used is preferably 0.1 to 3 moles, more preferably 0.5 to 2 moles relative to the amount of diamine used.

An end-modified polymer may be synthesized by further reacting a compound capable of reacting with the amino group at the polymer end with the polyamic acid ester obtained above. As such an end modifier, chlorocarbonyl compounds such as acryloyl chloride, methacryloyl chloride, isoxazole-5-carboxylic acid chloride, 2-furoyl chloride and the like can be mentioned.
The reaction of the polyamic acid ester with the terminal modifier can be carried out in an organic solvent, preferably in the presence of a base. The proportion of the terminal modifier used at this time is preferably 0.005 to 0.6 mol, and more preferably 0.01 to 0.2 mol per mol of diamine used in the reaction. . As a base, for example, tertiary amines such as pyridine and triethylamine can be preferably used. As the organic solvent, the description of organic solvents that can be used for the synthesis of polyamic acid can be applied, and for example, N, N-dimethylformamide, N-methyl-2-pyrrolidone, γ-butyrolactone, etc. are preferably used. be able to.

  Thus, a reaction solution containing the polyamic acid ester as the polymer (A) is obtained. The reaction solution may be used as it is for the preparation of a liquid crystal aligning agent, or may be subjected to the preparation of a liquid crystal aligning agent after isolating the polyamic acid ester contained in the reaction solution, or the isolated polyamic acid ester The liquid crystal aligning agent may be subjected to the preparation of the liquid crystal aligning agent. Isolation and purification of the polyamic acid ester can be carried out according to known methods.

  The polymer (A) may have only the structure (amic acid ester structure) represented by the above formula (1), or alternatively, a part of the polymer (A) may have an amic acid structure and an imide ring It may be a partial esterified product containing at least one of the structures (including an isoimide ring structure). From the viewpoint of sufficiently obtaining the effect of improving the warping of the substrate, the unevenness resistance around the sealing material in the liquid crystal display element (bezel unevenness resistance), the liquid crystal alignment property, and the voltage holding ratio, the polymer (A) has the above formula (1) It is preferable that it has 1 mol% or more with respect to the sum total of the amic acid ester structure which a polymer (A) has, the amic acid structure which a polymer (A) has, and an imide ring structure, 5 mol % Or more is more preferable, and 10 mol% or more is more preferable.

  The polymer (A) preferably has a solution viscosity of 15 to 1500 mPa · s when it is made a solution having a concentration of 15% by weight, and has a solution viscosity of 20 to 1200 mPa · s. Is more preferred. In addition, the solution viscosity (mPa · s) of this polymer is a polymer having a concentration of 15% by weight prepared using a good solvent (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) of the polymer (A) It is the value measured at 25 ° C. using a type E rotational viscometer for the solution.

  The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) of the polymer (A) is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000. It is. Further, the molecular weight distribution (Mw / Mn) represented by the ratio of the weight average molecular weight Mw and the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is preferably 15 or less, more preferably 10 or less. is there. By being in such a molecular weight range, good alignment and stability of the liquid crystal display element can be secured. In addition, a polymer (A) can be used individually by 1 type or in combination of 2 or more types.

<Polymer (B)>
The polymer (B) is a polymer having a partial structure (c-2), and specific examples include polyorganosiloxanes and polymers of monomers having a polymerizable carbon-carbon unsaturated bond.

[Polyorganosiloxane]
The polyorganosiloxane as the polymer (B) can be obtained, for example, by the hydrolysis / condensation reaction of a hydrolyzable silane compound.

The silane compound used in the above reaction may be a silane compound exhibiting hydrolyzability, and specific examples thereof include
3-glycidyloxypropyltrimethoxysilane, 3-glycidyloxypropyltriethoxysilane, 3-glycidyloxypropylmethyldimethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyldimethylmethoxysilane And epoxy group-containing silane compounds such as 3-glycidyloxypropyldimethylethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane and the like;

Alkoxysilane compounds such as tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, trimethoxysilylpropylsuccinic anhydride, dimethyldimethoxysilane, dimethyldiethoxysilane ;
3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, mercaptomethyltrimethoxysilane, mercaptomethyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-aminopropyltrimethoxysilane Nitrogen and sulfur-containing alkoxysilane compounds such as silane, 3-aminopropyltriethoxysilane, N- (3-cyclohexylamino) propyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane;
3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 6- (meth) acryloyloxyhexyltrimethoxysilane, 8- (meth) acryloyloxyoctyltrimethoxysilane, 3- (meth) acryloyloxypropyltrimethoxysilane Unsaturated bond-containing alkoxysilane compounds such as (meth) acryloyloxypropylmethyldimethoxysilane, 3- (meth) acryloyloxypropylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, p-styryltrimethoxysilane and the like;
And the like. These silane compounds may be used alone or in combination of two or more. In addition, "(meth) acryloyloxy" is a meaning including "acryloyloxy" and "methacryloyloxy."

  The above hydrolysis / condensation reaction can be carried out by reacting one or more of the above-mentioned silane compounds with water, preferably in the presence of a suitable catalyst and an organic solvent. In the hydrolysis / condensation reaction, the proportion of water used is preferably 0.5 to 100 mol, more preferably 1 to 30 mol, per 1 mol of the silane compound (total amount).

Examples of the catalyst used in the hydrolysis / condensation reaction include acids, alkali metal compounds, organic bases, titanium compounds and zirconium compounds. As specific examples of these, for example, inorganic acids such as hydrochloric acid, nitric acid and phosphoric acid, organic acids such as toluenesulfonic acid, phthalic acid, malonic acid, formic acid and oxalic acid, etc .; Sodium oxide, potassium hydroxide, sodium methoxide, potassium methoxide etc. as an organic base; for example, primary, secondary organic amines such as ethylamine, diethylamine, piperazine, piperidine, pyrrolidine, pyrrole: triethylamine, pyridine, 4-dimethylamino Tertiary organic amines such as pyridine: quaternary organic amines such as tetramethyl ammonium hydroxide can be mentioned respectively. Among these, alkali metal compounds or organic bases are preferable, and organic bases are more preferable.
The amount of organic base used varies depending on the type of organic base, reaction conditions such as temperature, etc., and should be set appropriately. For example, preferably 0.01 to 3 times the molar amount with respect to the total amount of silane compounds More preferably, it is 0.05-1 mol.

  As an organic solvent used in the case of said hydrolysis * condensation reaction, hydrocarbon, a ketone, ester, ether, alcohol etc. can be mentioned, for example. As specific examples thereof, hydrocarbons such as toluene and xylene; ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; esters such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, 3- As methoxybutyl acetate, ethyl lactate etc .; as ether, eg ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran etc .; As alcohol, eg 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether etc. Each can be mentioned. Among these, it is preferable to use a water insoluble or poorly water soluble organic solvent. In addition, these organic solvents can be used individually by 1 type or in mixture of 2 or more types. The proportion of the organic solvent used is preferably 10 to 10,000 parts by weight, more preferably 50 to 1,000 parts by weight, based on 100 parts by weight of the total silane compounds used in the reaction.

  The above hydrolysis / condensation reaction is preferably carried out by dissolving the silane compound as described above in an organic solvent, mixing this solution with an organic base and water, and heating with, for example, an oil bath. At the time of the hydrolysis / condensation reaction, the heating temperature is preferably 130 ° C. or less, more preferably 40 to 100 ° C. The heating time is preferably 0.5 to 12 hours, and more preferably 1 to 8 hours. During heating, the mixture may be stirred or may be under reflux. Further, after completion of the reaction, the organic solvent layer separated from the reaction solution is preferably washed with water. At the time of this washing, washing with water containing a small amount of salt (for example, an aqueous solution of about 0.2 wt% ammonium nitrate etc.) is preferable in that the washing operation becomes easy. Washing is performed until the aqueous layer after washing becomes neutral, and then the organic solvent layer is dried with a desiccant such as anhydrous calcium sulfate or molecular sieve if necessary, and then the solvent is removed. Can be obtained.

  When producing a TN type, STN type or vertical alignment type liquid crystal display element, at least a part of the polymer (B) is also referred to as a group capable of exhibiting pretilt angle characteristics (hereinafter, also referred to as "pretilt angle exhibiting group"). It may be a polyorganosiloxane having a side chain). Here, as the pretilt angle developing group, for example, an alkyl group having 2 to 20 carbon atoms, a fluoroalkyl group having 2 to 20 carbon atoms, an alkoxy group having 2 to 20 carbon atoms, and a steroid skeleton having 17 to 51 carbon atoms And groups having a structure in which two or more rings are linked, and the like. The alkyl group, the alkoxy group and the fluoroalkyl group in the pretilt angle developing group are preferably linear.

  The synthesis method of the polyorganosiloxane having a pretilt angle developing group is not particularly limited. For example, epoxy is obtained by hydrolysis / condensation reaction of a mixture of an epoxy group-containing silane compound or an epoxy group-containing silane compound and another silane compound. It can be obtained by a method of synthesizing a group-containing polyorganosiloxane and then reacting the obtained epoxy group-containing polyorganosiloxane with a carboxylic acid having a pretilt angle developing group.

  An epoxy group-containing polyorganosiloxane in view of suppressing a side reaction caused by an excessive amount of an epoxy group while making it possible to introduce a sufficient amount of a pretilt angle developing group to a side chain of a polymer The epoxy equivalent is preferably 80 to 10,000 g / mol, and more preferably 100 to 1,000 g / mol. Therefore, in synthesizing the epoxy group-containing polyorganosiloxane, it is preferable to adjust the use ratio of the epoxy group-containing silane compound so that the epoxy equivalent of the obtained polyorganosiloxane becomes the above range.

（式中、ｊは０〜１２の整数であり、ｈは１〜２０の整数である。Ｒ^７は１価の有機基であり、ｉは０〜５の整数である。）
なお、プレチルト角発現性基を有するカルボン酸は、これらのうちから選択される１種を単独で又は２種以上を組み合わせて使用することができる。 Specific examples of the carboxylic acid having a pretilt angle developing group include, for example, caproic acid, lauric acid, pentadecyl acid, palmitic acid, stearic acid, stearic acid, oleic acid, acetic acid, linoleic acid, linolenic acid, arachidic acid and the like having 6 carbon atoms 20 fatty acids, the compound etc. which are represented by each of following formula (4-1)-formula (4-10) are mentioned.

(Wherein, j is an integer of 0 to 12, h is an integer of 1 to 20. R ⁷ is a monovalent organic group, and i is an integer of 0 to 5).
In addition, the carboxylic acid which has a pretilt angle expression group can be used individually by 1 type selected from these, or in combination of 2 or more types.

  The reaction of the epoxy group-containing polyorganosiloxane with the carboxylic acid can preferably be carried out in the presence of a catalyst and an organic solvent. The proportion of the carboxylic acid to be reacted with the epoxy group-containing polyorganosiloxane is preferably 0.001 to 1.5 moles, relative to 1 mole of the epoxy groups contained in the epoxy group-containing polyorganosiloxane, and 0.01 It is more preferable to set it as -0.9 mol, and it is further more preferable to set it as 0.05-0.8 mol. When the proportion of the carboxylic acid used for the reaction with the epoxy group-containing polyorganosiloxane is less than 1 mole with respect to 1 mole of the epoxy group contained in the epoxy group-containing polyorganosiloxane, the epoxy group and the pretilt angle exhibiting property It is possible to obtain a polyorganosiloxane having a group in the side chain. It is preferable that a polymer (B) has an epoxy group in a side chain from the point which can fully acquire the reduction effect of the curvature of a board | substrate.

As a catalyst used for the said reaction, a compound well-known as a so-called hardening accelerator which accelerates | stimulates reaction of an organic base, an epoxy compound, etc. can be used, for example. Specifically, examples of the organic base include pyridine, 4-dimethylaminopyridine, tetramethylammonium hydroxide and the like. Further, as the above-mentioned curing accelerator, for example, benzyldimethylamine, 2-methylimidazole, diphenylphosphine, benzyltriphenylphosphonium chloride, zinc octylate, tin octylate, tetraethylammonium bromide, boron trifluoride, zinc chloride In addition to stannic chloride and the like, those known as latent curing accelerators can be used.
The above catalyst is preferably 100 parts by weight or less, more preferably 0.01 to 80 parts by weight, still more preferably 0.1 to 20 parts by weight, per 100 parts by weight of the epoxy group-containing polyorganosiloxane used in the reaction. Can be used in proportions.

  As an organic solvent used for the said reaction, hydrocarbon, ether, ester, a ketone, amide | amido, alcohol etc. can be mentioned, for example. Among these, ethers, esters and ketones are preferable from the viewpoint of the solubility of the raw material and the reaction product and the ease of purification of the reaction product. Specific examples of particularly preferred solvents include 2-butanone, 2-hexanone, methyl isobutyl ketone and butyl acetate. The organic solvent is preferably used in a proportion such that the solid concentration (the ratio of the total weight of components other than the solvent in the reaction solution to the total weight of the solution) is 0.1% by weight or more, It is more preferable to use it in the ratio which will be 5 to 50 weight%.

  The reaction temperature of the epoxy group-containing polyorganosiloxane and the carboxylic acid is preferably 0 to 200 ° C., more preferably 50 to 150 ° C. The reaction time is preferably 0.1 to 50 hours, more preferably 0.5 to 20 hours. Further, after completion of the reaction, the organic solvent layer separated from the reaction solution is preferably washed with water. After washing with water, the organic solvent layer is optionally dried with a suitable drying agent, and then the solvent is removed to obtain a polyorganosiloxane having a pretilt angle developing group in the side chain. In addition, the polyorganosiloxane which has a pretilt angle exhibiting group and a hydroxyl group in a side chain can be obtained by making epoxy group containing polyorganosiloxane and the carboxylic acid which has a pretilt angle exhibiting group react. It is preferable that a polymer (B) has a hydroxyl group at the point which the solubility with respect to the solvent of a polymer (B) improves, and the coating property (printability) of a liquid crystal aligning agent can be made favorable.

The polyorganosiloxane to be contained in the liquid crystal aligning agent of the present invention preferably has a solution viscosity of 2 to 600 mPa · s when it is made a solution with a concentration of 15% by weight, and 4 to 300 mPa · s It is more preferable to have solution viscosity. The solution viscosity (mPa · s) of the above-mentioned polymer is the E-type rotation of a polymer solution having a concentration of 15% by weight prepared using a good solvent (for example, N-methyl-2-pyrrolidone) of the polymer. It is a value measured at 25 ° C. using a viscometer.
The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography of the above polyorganosiloxane improves the liquid crystal alignment of the liquid crystal alignment film to be formed, and the temporal stability of the liquid crystal alignment. It is preferable that it is 500-50,000 from a viewpoint of ensuring, and it is more preferable that it is 1,000-30,000.

[Polymer of Monomer Having Polymerizable Carbon-Carbon Unsaturated Bond]
The polymer of the monomer having a polymerizable carbon-carbon unsaturated bond is also referred to as at least one monomer selected from the group consisting of (meth) acrylic compounds, aromatic vinyl compounds and maleimide compounds (hereinafter also referred to as "specific monomers"). The polymer which has a structural unit derived from can be used preferably.

Here, examples of the (meth) acrylic compound include unsaturated carboxylic acid, unsaturated carboxylic acid ester, unsaturated polyvalent carboxylic acid anhydride and the like.
As specific examples of these, as unsaturated carboxylic acid, for example, (meth) acrylic acid, (meth) acrylic acid ω-carboxypolycaprolactone, crotonic acid, α-ethyl acrylic acid, α-n-propyl acrylic acid, α- n-butyl acrylic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, vinylbenzoic acid and the like;

Examples of unsaturated carboxylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, allyl (meth) acrylate, (meth) acrylic Acid-n-butyl, (meth) acrylic acid-isobutyl, (meth) acrylic acid-t-butyl, (meth) acrylic acid cyclohexyl, benzyl (meth) acrylic acid, 2-ethylhexyl (meth) acrylic acid, (meth ) Alkyl group-containing unsaturated carboxylic acid esters such as lauryl acrylic acid; (meth) acrylic acid glycidyl, α-ethyl acrylic acid glycidyl, α-n-propyl acrylic acid glycidyl, α-n-butyl acrylic acid glycidyl, (meth) Acrylic acid 3,4-epoxybutyl, α-ethyl acrylic acid 3,4-epoxy ester (Meth) acrylic acid 3,4-epoxycyclohexylmethyl, (meth) acrylic acid 6,7-epoxyheptyl, α-ethyl acrylic acid 6,7-epoxyheptyl, acrylic acid 4-hydroxybutyl glycidyl ether, (meth ) Epoxy group-containing unsaturated carboxylic acid esters such as acrylic acid (3-ethyloxetan-3-yl) methyl; 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) acrylic acid Hydroxy-containing unsaturated carboxylic acid ester such as 4-hydroxybutyl; Silicon-containing unsaturated carboxylic acid ester such as trimethoxysilyl propyl (meth) acrylate; (meth) acrylic acid-N, N-dimethylaminoethyl (meth) Nitrogen-containing unsaturated carbon such as acrylic acid-N, N-diethylaminoethyl Acid esters; oxygen-containing unsaturated carboxylic acid esters such as methoxyethyl (meth) acrylate, methoxy polyethylene glycol (meth) acrylate, octoxy polyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate: α- Α-Alkoxyacrylic acid esters such as methyl methoxyacrylate and methyl α-ethoxyacrylate: crotonic acid esters such as methyl crotonate and ethyl crotonate;
As unsaturated polyvalent carboxylic acid anhydride, for example, maleic anhydride, itaconic acid anhydride, citraconic acid anhydride, cis-1,2,3,4-tetrahydrophthalic acid anhydride, etc. can be mentioned, respectively.

Examples of the aromatic vinyl compound include styrene, hydroxystyrene, methylstyrene, α-methylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 4-t-butylstyrene, vinylethylbenzene, divinylbenzene, t -Butoxystyrene, vinylbenzyldimethylamine, N, N-dimethylaminomethylstyrene, ethylstyrene, butylstyrene, vinylxylene, vinylnaphthalene, vinylpyridine, diphenylethylene, 4-vinylbenzyl glycidyl ether, etc .;
Examples of maleimide compounds include N-methyl maleimide, N-ethyl maleimide, N-butyl maleimide, N-cyclohexyl maleimide, N-phenyl maleimide, N-benzyl maleimide, N- (4-acetylphenyl) maleimide, N- (2 6,6-diethylphenyl) maleimide, N- (4-dimethylamino-3,5-dinitrophenyl) maleimide, N- [4- (2-benzoxazolyl) phenyl] maleimide and the like can be mentioned, respectively. The specific monomers can be used alone or in combination of two or more.

  When a polymer (B) is a polymer which has a structure derived from said specific monomer, the polymer which used only 1 type in a (meth) acrylic-type compound, an aromatic vinyl compound, and a maleimide compound for a monomer It may be a polymer obtained by combining two or more of these. Among them, a polymer of a monomer containing at least a (meth) acrylic compound (hereinafter, also referred to as "(meth) acrylic polymer") is preferable.

In the polymerization, from the viewpoint of improving the heat resistance of the liquid crystal alignment film, at least one selected from the group consisting of an aromatic vinyl compound and a maleimide compound may be used together with the (meth) acrylic compound. Moreover, you may use chain transfer agents, such as (alpha) -methylstyrene dimer, as needed with a (meth) acrylic-type compound.
The proportion of the (meth) acrylic compound used is preferably 50 mol% or more, more preferably 55 mol% or more, based on the total amount of the monomers used in the synthesis of the (meth) acrylic polymer. Preferably, it is more preferably 60 mol% or more.

In polymerization, a hydroxyl group-containing polymerizable unsaturated compound can be preferably used. In this case, by introducing a hydroxyl group derived from the compound into the side chain of the (meth) acrylic polymer, the solubility of the polymer (B) in a good solvent of the polyamic acid ester and the coating property on the substrate It is preferable at the point which can aim at an improvement.
The use ratio of the polymerizable unsaturated compound having a hydroxyl group is preferably 1 mol% or more, more preferably 1 to 50 mol%, and more preferably 5 to 40 based on the total amount of the monomers used for the polymerization. It is more preferable to set it as mol%.

In the synthesis of the polymer (B), the polymerization reaction of the above monomers is preferably carried out by radical polymerization. As a polymerization initiator to be used in the polymerization, for example, 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (4-) Azo compounds such as methoxy-2,4-dimethylvaleronitrile); organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butylperoxypivalate, 1,1'-bis (t-butylperoxy) cyclohexane; peroxidation Hydrogen; redox type initiators comprising these peroxides and a reducing agent, etc. may be mentioned. Among these, an azo compound can be preferably used. The polymerization initiator can be used singly or in combination of two or more.
The use ratio of the polymerization initiator is preferably 0.01 to 50 parts by weight, and more preferably 0.1 to 40 parts by weight with respect to 100 parts by weight of all the monomers used for the polymerization.

  The above 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 and hydrocarbon compounds. Among these, it is preferable to use at least one selected from the group consisting of alcohol and ether, and it is more preferable to use a partial ether of polyhydric alcohol. As a preferable specific example thereof, for example, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether acetate and the like can be mentioned. In addition, an organic solvent can be used individually by 1 type or in combination of 2 or more types.

  In the polymerization reaction, the reaction temperature is preferably 30 ° C. to 120 ° C., and more preferably 60 ° C. to 110 ° C. The reaction time is preferably 1 to 36 hours, and more preferably 2 to 24 hours. The amount (a) of the organic solvent used should be such that the total amount (b) of the monomers used for the reaction is 0.1 to 50% by weight with respect to the total amount (a + b) of the reaction solution Is preferred. After completion of the reaction, isolation and purification of the polymer can be carried out according to known methods, if necessary.

  When a TN type, STN type or vertical alignment type liquid crystal display device is manufactured, at least a part of the polymer (B) may be a polymer having the above pretilt angle developing group in a side chain. Although the synthesis method of the said polymer is not specifically limited, For example, the polymerization reaction of the mixture of the epoxy group containing polymerizable unsaturated compound, or the epoxy group containing polymerizable unsaturated compound, and the other polymerizable unsaturated compound A method of synthesizing an epoxy group-containing polymer and then reacting the obtained epoxy group-containing polymer with a carboxylic acid having a pretilt angle developing group can be mentioned.

In the epoxy group-containing polymer, the total amount (number of moles) of epoxy groups per 1 g is preferably 5.0 × 10 ⁻⁵ mol / g or more, and 1.0 × 10 ^{−4 to} 1.0 × It is more preferably 10 ⁻² mol / g, and still more preferably 5.0 × 10 ^{−4 to} 5.0 × 10 ⁻³ mol / g. Therefore, with respect to the use ratio of the epoxy group-containing polymerizable unsaturated compound, it is preferable to adjust the number of moles of the total of epoxy groups per 1 g of the epoxy group-containing polymer to be in the above numerical range.

  As a specific example of a carboxylic acid to be reacted with an epoxy group-containing polymer, an illustration of a carboxylic acid to be reacted with an epoxy group-containing polyorganosiloxane can be applied. The proportion of the carboxylic acid used is preferably 0.001 to 1.5 moles, and more preferably 0.01 to 0.9 moles, with respect to 1 mole in total of the epoxy groups in the polymer. More preferably, it is 0.05 to 0.8 mol. In addition, an epoxy group and a pretilt angle exhibiting group as a polymer (B) by making the use rate of the carboxylic acid used for reaction into less than 1 mol with respect to 1 mol of epoxy groups which an epoxy-group-containing polymer has. The polymer which has in the side chain can be obtained.

The reaction of the epoxy group-containing polymer with the carboxylic acid can be carried out preferably in the presence of a catalyst and an organic solvent. As a catalyst in the above reaction, for example, a compound known as a so-called curing accelerator which accelerates the reaction of an organic base and an epoxy compound can be used.
Examples of the organic base include: primary, secondary organic amines such as ethylamine, diethylamine, piperazine and piperidine; tertiary organic amines such as triethylamine, tri-n-propylamine, tri-n-butylamine and pyridine; tetramethylammonium hydroxy And quaternary organic amines such as sodium hydroxide; and the like. Among these, tertiary organic amines or quaternary organic amines are preferred as the organic base.
Examples of the curing accelerator include tertiary amines, imidazole compounds, organic phosphorus compounds, quaternary phosphonium salts, diazabicycloalkenes, organic metal compounds such as zinc octylate and tin octylate, quaternary ammonium salts, boron In addition to compounds and metal halide compounds such as zinc chloride and stannic chloride, etc., known ones as latent curing accelerators can be used. Among these, preferred are quaternary ammonium salts such as tetraethylammonium bromide and tetrabutylammonium bromide.
The amount of the catalyst used is preferably 100 parts by weight or less, more preferably 0.01 to 100 parts by weight or less, still more preferably 0.1 to 20 parts by weight, based on 100 parts by weight of the epoxy group-containing polymer to be reacted with carboxylic acid. It is a weight part.

As an organic solvent used for reaction, the illustration of the organic solvent which can be used for the synthesis | combination of a polymer (B) can be applied, It is preferable that it is ester or a ketone especially. The organic solvent is preferably used in a proportion such that the solid concentration (the ratio of the total weight of components other than the solvent in the reaction solution to the total weight of the solution) is 0.1% by weight or more, It is more preferable to use it in the ratio which will be 5 to 50 weight%.
In the reaction of the epoxy group-containing polymer with the carboxylic acid, the reaction temperature is preferably 0 to 200 ° C., and more preferably 50 to 150 ° C. The reaction time is preferably 0.1 to 50 hours, and more preferably 0.5 to 20 hours.

  The reaction solution containing the polymer (B) may be used as it is for the preparation of a liquid crystal aligning agent, or the polymer contained in the reaction solution may be used for the preparation of a liquid crystal aligning agent after isolation. Alternatively, the isolated polymer may be purified and then subjected to preparation of a liquid crystal aligning agent. The isolation and purification of the polymer can be carried out according to known methods.

The polymer (B) obtained as described above preferably has a solution viscosity of 2 to 600 mPa · s when it is made a solution with a concentration of 15% by weight, and 4 to 300 mPa · s. It is more preferable to have solution viscosity. The solution viscosity (mPa · s) of the above-mentioned polymer is the E-type rotation of a polymer solution having a concentration of 15% by weight prepared using a good solvent (for example, N-methyl-2-pyrrolidone) of the polymer. It is a value measured at 25 ° C. using a viscometer.
The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography for the polymer (B) improves the liquid crystal alignment of the liquid crystal alignment film to be formed, and temporally stabilizes the liquid crystal alignment. From the viewpoint of securing the property, it is preferably 250 to 500,000, more preferably 500 to 300,000, and still more preferably 1,000 to 200,000. In addition, a polymer (B) can be used individually by 1 type or in combination of 2 or more types.

As a preferable aspect in case the liquid crystal aligning agent of this invention contains a polymer (A) and a polymer (B) as a polymer component, the following [1] and [2] are mentioned.
[1] An embodiment containing a polyamic acid ester as the polymer (A) and containing a polyorganosiloxane as the polymer (B).
[2] An embodiment containing a polyamic acid ester as the polymer (A) and a (meth) acrylic polymer as the polymer (B).
The blend ratio of the polymer (A) to the polymer (B) in the liquid crystal aligning agent is a polymer (from the viewpoint of achieving a well-balanced effect of reducing the warping of the substrate, bezel unevenness resistance, liquid crystal alignment and voltage retention). The weight ratio of A) / polymer (B) is preferably 20/80 to 98/2. More preferably, it is 25/75 to 97/3, still more preferably 30/70 to 95/5, and particularly preferably 40/60 to 93/7. The liquid crystal aligning film obtained using the liquid crystal aligning agent containing a polymer (A) and a polymer (B) is favorable also about the permeability | transmittance of a film | membrane, and it is suitable at the point which can make the display quality of a display apparatus favorable. It is.

<Other ingredients>
The liquid crystal aligning agent of the present invention may further contain other components other than the polymer (A) and the polymer (B) as necessary. Examples of the other components include polymers other than the polymer (A) and the polymer (B), compounds having at least one epoxy group in the molecule (hereinafter referred to as “epoxy group-containing compounds”), A functional silane compound etc. can be mentioned.

[Other polymers]
The above other polymers can be used to improve solution properties and electrical properties. Examples of such other polymers include polyamic acids, polyimides, polyesters, polyamides, cellulose derivatives, polyacetals and the like.
When mix | blending said other polymer with a liquid crystal aligning agent, it is preferable to make the compounding ratio into 30 weight part or less with respect to 100 weight part of all the polymers in this composition, and 0.1-20 weight. It is more preferable to set it as a part, and it is more preferable to set it as 0.1 to 10 parts by weight.

[Epoxy group-containing compound]
An epoxy group containing compound can be used in order to improve adhesiveness with the substrate surface in a liquid crystal aligning film. Here, as the epoxy group-containing compound, for example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1 , 6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, 2, 2-dibromo neopentyl glycol diglycidyl ether, N, N, N ', N'-tetraglycidyl-m-xylene diamine 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycidyl-4,4′-diaminodi Preferred are epoxy group-containing polyorganosiloxanes described in WO 2009/096598, and the like. It can be mentioned.
When these epoxy group-containing compounds are blended in a liquid crystal aligning agent, the blending ratio is preferably 40 parts by weight or less, and 0.1 to 30 parts by weight with respect to 100 parts by weight in total of the polymers contained in the liquid crystal aligning agent. Part is more preferred.

[Functional Silane Compound]
The functional silane compound can be used to improve the printability of the liquid crystal aligning agent. Such functional silane compounds include, for example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) ) 3-Aminopropyltrimethoxysilane, 3-ureidopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-triethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4 , 7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, methyl 9-triethoxysilyl-3,6-diazanonanoate, N -Benzyl-3-aminopropyl Trimethoxysilane, N- phenyl-3-aminopropyltrimethoxysilane, glycidoxy methyl trimethoxy silane, can be cited glycidoxy methyl triethoxy silane.
When a functional silane compound is mix | blended with a liquid crystal aligning agent, 2 parts by weight or less is preferable with respect to a total of 100 parts by weight of the polymer, and 0.02 to 0.2 parts by weight is more preferable.

  As other components, metal chelate compounds such as diisopropoxyethyl acetoacetate aluminum and tris (acetylacetonate) aluminum besides the above; curing accelerators such as phenols and silanols; nonionic surfactant, anionic surfactant , Cationic surfactants, amphoteric surfactants, silicone surfactants, surfactants such as fluorosurfactants; antioxidants such as phenolic antioxidants and amine antioxidants; ethylene glycol diacrylate, Multifunctional (meth) acrylates such as 1,6-hexanediol diacrylate; etc. may be used.

<Solvent>
The liquid crystal aligning agent of the present invention is prepared as a liquid composition in which the above-mentioned polymer and other components which are optionally used are preferably dispersed or dissolved in a suitable solvent.

  As the solvent to be used, for example, N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene Glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxy propionate, ethyl ethoxy propionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol i-propyl ether, Ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol Diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisopentyl ether, ethylene carbonate, propylene carbonate, etc. It can be mentioned. These can be used individually by 1 type or in mixture of 2 or more types.

  The solid content concentration in the liquid crystal aligning agent of the present invention (the ratio of the total weight of components other than the solvent of the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility and the like. , Preferably in the range of 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention is applied to the substrate surface as described later, and preferably heated to form a coating film which is a liquid crystal alignment film or a coating film which becomes a liquid crystal alignment film. At this time, when the solid content concentration is less than 1% by weight, the film thickness of the coating film becomes too small, and it becomes difficult to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, the film thickness of the coating film becomes too large to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal alignment agent increases and the coatability decreases. There is a tendency.

  The particularly preferable solid concentration range varies depending on the application of the liquid crystal aligning agent and the method used when applying the liquid crystal aligning agent to the substrate. For example, when a liquid crystal aligning agent for a liquid crystal cell is applied to a substrate by a spinner method, the solid content concentration (the ratio of the total weight of all components other than the solvent in the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) The range of 1.5 to 4.5% by weight is particularly preferable. In the case of the printing method, it is particularly preferable to set the solid content concentration in the range of 3 to 9% by weight and thereby to set the solution viscosity in the range of 12 to 50 mPa · s. In the case of the inkjet method, it is particularly preferable to set the solid content concentration in the range of 1 to 5% by weight and thereby to set the solution viscosity in the range of 3 to 15 mPa · s. The temperature at the time of preparing the liquid crystal aligning agent of the present invention is preferably 10 to 50 ° C., more preferably 20 to 30 ° C. Moreover, about the liquid crystal aligning agent for retardation films, solid content concentration of a liquid crystal aligning agent is 0.2 to 10 weight% from a viewpoint of making coating property of a liquid crystal aligning agent, and the film thickness of the coating film formed appropriate. Is preferably in the range of 3 to 10% by weight.

<Liquid crystal display element and retardation film>
A liquid crystal aligning film can be manufactured by using the liquid crystal aligning agent of this invention demonstrated above. Moreover, the liquid crystal aligning film formed using the liquid crystal aligning agent of this invention can be preferably applied to the liquid crystal aligning film for liquid crystal display elements (for liquid crystal cells), and the liquid crystal aligning film for retardation films. Hereinafter, the liquid crystal display element and the retardation film of the present invention will be described.

[Liquid crystal display element]
The liquid crystal display element of the present invention comprises a liquid crystal alignment film formed using the liquid crystal alignment agent. The operation mode of the liquid crystal display element of the present invention is not particularly limited. For example, TN type, STN type, VA type (including VA-MVA type, VA-PVA type, etc.), IPS type, FFS type, OCB type, etc. Can be applied to the operation mode of The liquid crystal display element of the present invention can be produced, for example, by the process including the following (1-1) to (1-3). In the step (1-1), the substrate used differs depending on the desired operation mode. The step (1-2) and the step (1-3) are common to each operation mode.

[Step (1-1): Formation of Coating Film]
First, the liquid crystal aligning agent of the present invention is coated on a substrate, and then the coated surface is heated to form a coating film on the substrate.
(1-1A) For example, when manufacturing a TN type, STN type or VA type liquid crystal display element, first, each transparent conductive film is formed by using two substrates provided with the patterned transparent conductive film as a pair. On the surface, the liquid crystal aligning agent of the present invention is preferably applied by offset printing, spin coating, roll coating or inkjet printing. As the substrate, for example, glass such as float glass and soda glass; transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate and poly (alicyclic olefin) can be used. As a transparent conductive film provided on one surface of the substrate, a NESA film (registered trademark of PPG, USA) made of tin oxide (SnO ₂ ), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), etc. It can be used. In order to obtain a patterned transparent conductive film, for example, a method of forming a pattern by photo etching after forming a non-patterned transparent conductive film; a method of using a mask having a desired pattern when forming a transparent conductive film; And so on. At the time of application of the liquid crystal aligning agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film, a functional silane compound and a functional titanium compound are formed on the surface of the substrate surface on which the coating film is formed. It is possible to pre-treat application etc. beforehand.

  After the application of the liquid crystal alignment agent, preheating (pre-baking) is preferably performed for the purpose of preventing dripping of the applied liquid crystal alignment agent. The prebake temperature is preferably 30 to 200 ° C., more preferably 40 to 150 ° C., and particularly preferably 40 to 100 ° C. The pre-bake time is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes. Thereafter, a baking (post-baking) step is carried out for the purpose of completely removing the solvent and optionally thermally imidizing the amic acid structure present in the polymer. The baking temperature (post-baking temperature) at this time is preferably 80 to 300 ° C., more preferably 120 to 250 ° C. The post-baking time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The film thickness of the film thus formed is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

  (1-1B) When manufacturing an IPS type or FFS type liquid crystal display element, an electrode is provided on the electrode formation surface of a substrate provided with an electrode made of a transparent conductive film or a metal film patterned in a comb shape. The liquid crystal aligning agent of the present invention is applied to one side of the opposite substrate which has not been treated, and then the coated surface is heated to form a coating film. The material of the substrate and the transparent conductive film used at this time, the coating method, the heating conditions after coating, the patterning method of the transparent conductive film or metal film, the pretreatment of the substrate, and the preferred thickness of the coating film formed It is the same as (1-1A). For example, a film made of a metal such as chromium can be used as the metal film.

  In any case of the above (1-1A) and (1-1B), a liquid crystal aligning agent is applied on the substrate and then an organic solvent is removed to form a liquid crystal alignment film or a coating film to be a liquid crystal alignment film. Be done. At this time, the dehydration ring closure reaction of the polyamic acid ester and the polyimide compounded with the liquid crystal aligning agent of the present invention and the polyamic acid compounded according to the need is promoted by further heating after forming the coating film, thereby further imidation It may be a coated film.

[Step (1-2): Orientation Treatment]
In the case of producing a TN type, STN type, IPS type or FFS type liquid crystal display element, a treatment (orientation treatment) for imparting liquid crystal alignment ability to the coating film formed in the above step (1) is carried out. Thereby, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film. Examples of the orientation treatment include rubbing treatment in which a coating film is rubbed in a predetermined direction by a roll wound with a cloth made of fibers such as nylon, rayon, cotton, etc .; light orientation treatment in which light is irradiated to the coating film; On the other hand, when manufacturing a vertical alignment type liquid crystal display element, the coating film formed in the above step (1-1) can be used as a liquid crystal alignment film as it is, but the coating film is subjected to alignment treatment May be

  The liquid crystal alignment film after rubbing treatment is further irradiated with light to a part of the liquid crystal alignment film to change the pretilt angle of a part of the liquid crystal alignment film, or The resist film may be formed on the portion, and the rubbing treatment may be performed in a direction different from the rubbing treatment described above, and then the resist film may be removed to make the liquid crystal alignment film have different liquid crystal alignment capabilities for each region. . In this case, it is possible to improve the visibility characteristics of the obtained liquid crystal display element. The liquid crystal alignment film suitable for a VA type liquid crystal display element can be suitably used also for a liquid crystal display element of PSA (Polymer sustained alignment) type.

[Step (1-3): Construction of Liquid Crystal Cell]
Two substrates on which the liquid crystal alignment film is formed as described above are prepared, and a liquid crystal is disposed between two substrates disposed opposite to each other to manufacture a liquid crystal cell. For example, the following two methods may be mentioned to manufacture a liquid crystal cell. The first method is a conventionally known method. First, two substrates are disposed opposite to each other with a gap (cell gap) such that the liquid crystal alignment films face each other, and the peripheral portions of the two substrates are bonded using a sealing material, and the substrate surface and the sealing material After the liquid crystal is injected and filled in the cell gap partitioned by the above, the liquid crystal cell is manufactured by sealing the injection hole. The second method is a method called ODF (One Drop Fill) method. For example, a UV-curable sealant is applied to a predetermined place on one of the two substrates on which the liquid crystal alignment film is formed, and then liquid crystal is dropped on a predetermined number of places on the liquid crystal alignment film. After that, the other substrate is bonded so that the liquid crystal alignment film faces each other, and the liquid crystal is spread over the entire surface of the substrate, and then the entire surface of the substrate is irradiated with ultraviolet light to cure the sealing material. Do. Regardless of which method is used, the liquid crystal cell manufactured as described above is further heated to a temperature at which the liquid crystal used takes an isotropic phase, and then gradually cooled to room temperature, thereby achieving flow alignment at the time of liquid crystal filling. It is desirable to remove.

As a sealing material, what is normally used can be used as an adhesive agent for liquid crystals, for example, the epoxy resin etc. which contain a hardening agent can be used. Further, as the sealing material, one further containing an aluminum oxide sphere as a spacer may be used.
Examples of liquid crystals include nematic liquid crystals and smectic liquid crystals, among which nematic liquid crystals are preferred. For example, Schiff base liquid crystals, azoxy liquid crystals, biphenyl liquid crystals, phenylcyclohexane liquid crystals, ester liquid crystals, terphenyl liquid crystals, biphenyl A cyclohexane type liquid crystal, a pyrimidine type liquid crystal, a dioxane type liquid crystal, a bicyclooctane type liquid crystal, a cubane type liquid crystal, or the like can be used. In addition, cholesteric liquid crystals such as colestil chloride, cholesteryl nonaate, cholesteryl carbonate, and the like; and chiral agents such as those sold under the trade names "C-15" and "CB-15" (manufactured by Merck). And ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutyl cinnamate may be added and used.

  Then, a polarizing plate is attached to the outer surface of the liquid crystal cell, whereby the liquid crystal display element of the present invention can be obtained. As a polarizing plate to be bonded to the outer surface of a liquid crystal cell, the polarizing plate or H film itself is a polarizing film called “H film” which absorbs iodine while drawing and orienting polyvinyl alcohol, sandwiched by a cellulose acetate protective film The polarizing plate which consists of can be mentioned.

[Retardation film]
Next, the method of manufacturing a retardation film using the liquid crystal aligning agent of this invention is demonstrated. In the production of the retardation film of the present invention, it is possible to form a uniform liquid crystal alignment film while suppressing generation of dust and static electricity during the process, and a suitable photomask is used at the time of light irradiation. It is preferable to use the light alignment method in that a plurality of regions having different liquid crystal alignment directions can be arbitrarily formed on the substrate. Specifically, it can manufacture by passing through the following process (2-1)-a process (2-3).

[Step (2-1): Formation of Coating Film by Liquid Crystal Alignment Agent]
First, the liquid crystal aligning agent of the present invention is coated on a substrate to form a coating film. As a substrate used here, a transparent substrate made of a synthetic resin such as triacetyl cellulose (TAC), polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polyamide, polyimide, polymethyl methacrylate, polycarbonate etc. is preferably exemplified. Can. Among these, TAC is generally used as a protective layer of a polarizing film in a liquid crystal display element. In addition, polymethyl methacrylate can be preferably used as a substrate for a retardation film in that the solvent has low hygroscopicity, good optical properties, and low cost. In addition, to the board | substrate used for application | coating of a liquid crystal aligning agent, in order to make the adhesiveness of a substrate surface and a coating film further favorable, the conventionally well-known pretreatment is carried out to the surface which forms a coating film among substrate surfaces. It may be implemented.

  Retardation films are often used in combination with polarizing films. At this time, in order to exhibit desired optical characteristics, it is necessary to precisely control the angle with respect to the polarization axis of the polarizing film in a specific direction to bond the retardation film. Therefore, here, by forming a liquid crystal alignment film having liquid crystal alignment ability in the direction of a predetermined angle on a substrate such as a TAC film or polymethyl methacrylate, the retardation film is controlled on the polarizing film while controlling the angle. The step of bonding can be omitted. Further, this can contribute to the improvement of the productivity of the liquid crystal display element. In order to form a liquid crystal alignment film having liquid crystal alignment ability in the direction of a predetermined angle, it is preferable to carry out by the photo alignment method.

The application of the liquid crystal alignment agent onto the substrate can be carried out by an appropriate application method, for example, roll coater method, spinner method, printing method, ink jet method, bar coater method, extrusion die method, direct gravure coater method, chamber Doctor coater method, offset gravure coater method, single roll kiss coater method, reverse kiss coater method using small diameter gravure roll, three reverse roll coater method, four reverse roll coater method, slot die method, air doctor coater method A positive rotation roll coater method, a blade coater method, a knife coater method, an impregnation coater method, an MB coater method, an MB reverse coater method or the like can be employed.
After coating, the coated surface is heated (baked) to form a coating. The heating temperature at this time is preferably 40 to 150 ° C., and more preferably 80 to 140 ° C. The heating time is preferably 0.1 to 15 minutes, and more preferably 1 to 10 minutes. The film thickness of the coating film formed on the substrate is preferably 1 to 1,000 nm, more preferably 5 nm to 500 nm.

[Step (2-2): Light Irradiation Step]
Next, the coating film formed on the substrate as described above is irradiated with light to impart liquid crystal alignment ability to the coating film to form a liquid crystal alignment film. Here, as light to be irradiated, for example, ultraviolet light including visible light having a wavelength of 150 to 800 nm can be mentioned. Among these, ultraviolet rays containing light of a wavelength of 300 to 400 nm are preferable. The irradiation light may be polarized or non-polarized. It is preferable to use light including linear polarization as the polarization.
When the light to be used is polarized light, the light may be irradiated from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these. In the case of irradiating non-polarized light, it is necessary to carry out from a direction oblique to the substrate surface. As a light source to be used, a low pressure mercury lamp, a high pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, a mercury-xenon lamp (Hg-Xe lamp) etc. can be mentioned, for example. Polarization can be obtained by means of using these light sources, for example, in combination with filters, diffraction gratings and the like. The dose of light is preferably in a 0.1~1,000mJ / cm ^2, more preferably to 1 to 500 mJ / cm ^2, and even more preferably from 2~200mJ / cm ^2.

[Step (2-3): Formation of Liquid Crystal Layer]
Next, a polymerizable liquid crystal is applied and cured on the coating film after the light irradiation as described above. Thereby, a coating film (liquid crystal layer) containing a polymerizable liquid crystal is formed. The polymerizable liquid crystal used herein is a liquid crystal compound or a liquid crystal composition which is polymerized by at least one treatment of heating and light irradiation. As such a polymerizable liquid crystal, conventionally known ones can be used. Specifically, for example, non-patent document 1 (“UV-curable liquid crystal and its application”, liquid crystal, Volume 3, No. 1 (1999) And nematic liquid crystals described in pp. 34-42). In addition, it may be a cholesteric liquid crystal, a discotic liquid crystal, a twisted nematic alignment liquid crystal to which a chiral agent is added, or the like. The polymerizable liquid crystal may be a mixture of a plurality of liquid crystal compounds. The polymerizable liquid crystal may further be a composition containing a known polymerization initiator, a suitable solvent and the like.
In order to apply the above-mentioned polymerizable liquid crystal on the formed liquid crystal alignment film, an appropriate application method such as a bar coater method, a roll coater method, a spinner method, a printing method, an ink jet method can be adopted. .

Next, the coating film of the polymerizable liquid crystal formed as described above is cured by at least one treatment selected from heating and light irradiation to form a liquid crystal layer. Favorable orientation can be obtained by performing these treatments in a superimposed manner, which is preferable.
The heating temperature of a coating film is suitably selected by the kind of polymeric liquid crystal to be used. For example, when using RMS03-013C manufactured by Merck, it is preferable to heat at a temperature in the range of 40 to 80 ° C. The heating time is preferably 0.5 to 5 minutes.
As the irradiation light, non-polarized ultraviolet light having a wavelength in the range of 200 to 500 nm can be preferably used. The irradiation dose of light, preferably in the 50~10,000mJ / cm ^2, and more preferably a 100~5,000mJ / cm ^2.
The thickness of the liquid crystal layer to be formed is appropriately set according to the desired optical characteristics. For example, in the case of producing a half-wave plate in visible light with a wavelength of 540 nm, the thickness is selected such that the retardation of the formed retardation film is 240 to 300 nm. The thickness is selected such that the phase difference is 120 to 150 nm. The thickness of the liquid crystal layer capable of obtaining the desired retardation is different depending on the optical properties of the polymerizable liquid crystal used. For example, when using RMS 03-013C manufactured by Merck, the thickness for producing a quarter wave plate is in the range of 0.6 to 1.5 μm.

  The retardation film obtained as described above can be preferably applied to a retardation film of a liquid crystal display element. The liquid crystal display element to which the retardation film of the present invention is applied is not limited in its operation mode, and can be applied to various known modes such as TN type, STN type, IPS type, FFS type, VA type and the like. . The retardation film is used, for example, by sticking the surface of the retardation film on the substrate side to the outer surface of the polarizing plate disposed on the viewing side of the liquid crystal display element. In this case, preferably, the substrate of the retardation film is made of TAC or an acrylic substrate, and the substrate of the retardation film is also made to function as a protective film of a polarizing film. Moreover, the said retardation film may be arrange | positioned and used between the polarizing plate arrange | positioned at the visual recognition side of a liquid crystal display element, and a liquid crystal cell.

  The liquid crystal display device of the present invention can be effectively applied to various devices, and, for example, clocks, portable games, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, It can be used for various displays such as various monitors, liquid crystal televisions, and information displays.

  Hereinafter, the present invention will be more specifically described by way of examples, but the present invention is not limited to these examples.

The weight average molecular weight of each polymer, the imidation ratio of polyimide, the solution viscosity of each polymer solution, and the epoxy equivalent in the synthesis example were measured by the following methods.
[Weight average molecular weight of polymer]
The weight average molecular weight Mw of the polymer is a polystyrene conversion value measured by gel permeation chromatography under the following conditions.
Column: Tosoh Corp. TSKgel GRC XLII
Solvent: tetrahydrofuran or N, N-dimethylformamide solution containing lithium bromide and phosphoric acid Temperature: 40 ° C.
Pressure: 68 kgf / cm ²
[Imidation rate of polyimide]
A solution containing a polyimide is introduced into pure water, and the obtained precipitate is sufficiently dried under reduced pressure at room temperature and then dissolved in deuterated dimethyl sulfoxide to measure ¹ H-NMR at room temperature using tetramethylsilane as a reference substance. did. The imidation ratio [%] was determined from the obtained ¹ H-NMR spectrum using the following formula (1).
Imidation ratio [%] = (1−A ¹ / A ² × α) × 100 (1)
(In the formula (1), A ¹ is a proton-derived peak area of an NH group appearing in the vicinity of a chemical shift of 10 ppm, A ² is a peak area derived from other protons, and α is a precursor of a polymer (polyamic acid It is the number ratio of other protons to one proton of NH group in).
Solution viscosity of polymer solution
The solution viscosity [mPa · s] of the polymer solution was measured at 25 ° C. using an E-type rotational viscometer for a solution prepared to have a polymer concentration of 15% by weight using a predetermined solvent.
[Epoxy equivalent]
The epoxy equivalent was measured according to the "hydrochloric acid-methyl ethyl ketone method" of JIS C2105.

<Synthesis of polyamic acid ester>
Synthesis Example 1-1 Synthesis of Polymer (A-1)
6.92 g (80 mol parts per 100 mol parts of the total amount of diamine used in the synthesis) and 3.17 g (20 mol parts) of 4,4'-diaminodiphenylmethane as a diamine, 15 ml of pyridine as a base Also, 505 ml of N-methyl-2-pyrrolidone (NMP) was added and dissolved as a solvent. While stirring this solution with water cooling, 23.05 g (97 parts by mole) of dimethyl-1,3-bis (chlorocarbonyl) cyclobutane-2,4-carboxylate is added, and the solid concentration becomes 5% by weight. NMP was added as such and stirred for 4 hours with water cooling. This solution is poured into 250 g of water to precipitate a polymer, the polymer is separated by suction filtration, washed again with 250 g of water, washed three times with 63 g of methanol, and dried under reduced pressure at 40 ° C. 22 g of a polyamic acid ester powder of the polymer (A-1) was obtained. The weight average molecular weight of this polymer (A-1) was Mw = 27,000. The obtained polymer (A-1) was prepared to be 15% by weight with NMP.

Synthesis Example 1-2 Synthesis of Polymer (A-2)
2.00 g (0.01 mol) of 4,4'-diaminodiphenylmethane as a diamine, 40.94 g of N-methyl-2-pyrrolidone, 1.925 g (0.024 mol) of pyridine as a base were added and dissolved by stirring . Next, 2.82 g (0.0095 mol) of dimethyl-1,3-bis (chlorocarbonyl) cyclobutane-2,4-carboxylate was added while stirring this diamine solution, and the reaction was carried out for 4 hours under water cooling. Thereafter, 0.1725 g (0.0013 mol) of isoxazole-5-carboxylic acid chloride was added and reacted for 30 minutes under water cooling. Thereafter, 45.06 g of N-methyl-2-pyrrolidone was added to the reaction solution, and stirred at room temperature (20 ° C.) for 15 minutes. The obtained polyamic acid ester solution was poured into 495 g of ethanol while stirring, and the precipitated white precipitate was collected by filtration. Subsequently, the polymer is washed with 226 g of ethanol once, 451 g of water twice, 451 g of ethanol once, 113 g of ethanol three times, and dried to obtain polyamic acid ester powder 3 of polymer (A-2). I got .5g. Moreover, the weight average molecular weight of this polymer (A-2) was Mw = 18,000. The obtained polymer (A-2) was prepared to be 15% by weight with NMP.

<Synthesis of Polyorganosiloxane>
Synthesis Example 2-1 Synthesis of Polymer (BSi-1)
In a reaction vessel equipped with a stirrer, thermometer, dropping funnel and reflux condenser, 100.0 g of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECETS) as a hydrolysable silane compound, methyl isobutyl as a solvent 500 g of ketone and 10.0 g of triethylamine as a catalyst were charged and mixed at room temperature. After 100 g of deionized water was added dropwise from a dropping funnel over 30 minutes, the reaction was carried out at 80 ° C. for 6 hours while mixing under reflux. After completion of the reaction, the organic layer is taken out and washed with a 0.2 wt% aqueous ammonium nitrate solution until the water after washing becomes neutral, and then the solvent and water are distilled off under reduced pressure to obtain an epoxy group. The polyorganosiloxane was obtained as a viscous clear liquid. ¹ H-NMR analysis of this polyorganosiloxane having an epoxy group shows that a peak based on the epoxy group is obtained in the vicinity of the chemical shift (δ) = 3.2 ppm according to theoretical strength, and It was confirmed that no side reaction had occurred. The epoxy equivalent of this epoxy group-containing polyorganosiloxane was measured to be 186 g / equivalent.
Then, in a 200 mL three-necked flask, 10.0 g of the epoxy group-containing polyorganosiloxane obtained above, 30.28 g of methyl isobutyl ketone as a solvent, 3.87 g of 4- (4-pentylcyclohexyl) benzoic acid as a carboxylic acid (epoxy It corresponds to 25 mol% relative to the epoxy group of the group-containing polyorganosiloxane), and 0.10 g of UCAT 18X (trade name, manufactured by San Apro Co., Ltd.) as a catalyst is charged, and the reaction is carried out under stirring at 100 ° C. for 48 hours. went. After completion of the reaction, ethyl acetate was added to the reaction mixture, the solution obtained was washed three times with water, and the solvent was distilled off to obtain 9.5 g of polyorganosiloxane (BSi-1) having a pretilt angle developing group . The weight average molecular weight Mw of the obtained polymer was 5,500.

Synthesis Example 2-2 to Synthesis Example 2-4
An epoxy group-containing polyorganosiloxane was synthesized in the same manner as in Synthesis Example 2-1 except that the types and amounts of hydrolyzable silane compounds and carboxylic acids were as described in Table 1 below, and epoxy group-containing polyorgano compounds were synthesized. By reacting the siloxane and the carboxylic acid, polyorganosiloxanes (BSi-2) to (BSi-4) were obtained respectively. The Mw of these polyorganosiloxanes is shown in Table 1.

In Table 1, the numerical value of the hydrolyzable silane compound indicates the use ratio [mol%] of each compound to the total amount of monomers used for polymerization. The numerical value of the carboxylic acid indicates the ratio [mol%] of epoxy group-containing polyorganosiloxane used for the reaction to the epoxy group. The abbreviation of each compound in Table 1 has the following meaning, respectively.
(Hydrolyzable silane compound)
ECETS: 2- (3,4-Epoxycyclohexyl) ethyltrimethoxysilane (carboxylic acid)
PCHBA: 4- (4-pentylcyclohexyl) benzoic acid OCTBA: 4-octyloxybenzoic acid SACY: succinic acid = 5 = -cholestan-3-yl PCA: 4-phenoxycinnamic acid

<Synthesis of Polymer of Monomer Having Polymerizable Carbon-Carbon Double Bond>
Synthesis Example 3-1 Synthesis of Polymer (BAc-1)
In a reaction vessel equipped with a stirrer, a thermometer and a reflux condenser, as a polymerizable unsaturated compound, 3,4-epoxycyclohexylmethyl methacrylate (ECMMA, 60 moles per 100 moles of the total amount of monomers used for polymerization) Parts), 2-hydroxyethyl methacrylate (HEMA, 15 mol parts), N-cyclohexyl maleimide (CMI, 10 mol parts), and styrene (ST, 15 mol parts) are charged, and the total of the polymerizable unsaturated compounds is added. The mixture was dissolved by adding diethylene glycol ethyl methyl ether to 50 wt%. Here, 2,2′-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator, 3 mol% with respect to the total number of moles of the polymerizable unsaturated compound, and α-methylstyrene dimer as a chain transfer agent Only 0.5 times the weight of the polymerization initiator was added. Next, the system was purged with nitrogen by bubbling with a nitrogen stream for 10 minutes, and then a polymerization reaction was performed at 70 ° C. for 5 hours in a nitrogen atmosphere. After completion of the reaction, the reaction mixture was poured into a large excess of methanol to precipitate a reaction product. The recovered precipitate was washed with methanol and then dried under reduced pressure at 40 ° C. for 15 hours to obtain a methacrylic acid ester copolymer having an epoxy group.
Then, in a 200 mL three-necked flask, 10.0 g of the epoxy group-containing methacrylic acid ester copolymer obtained above, 30.28 g of methyl isobutyl ketone as a solvent, and 4- (4-pentylcyclohexyl) benzoic acid as a carboxylic acid. C. 01 g (corresponding to 25 mol% based on the epoxy group-containing methacrylic acid ester copolymer used for polymerization) and 0.10 g of UCAT 18X (trade name, manufactured by San-Apro Co., Ltd.) as a catalyst are charged, The reaction was carried out with stirring for 12 hours. After completion of the reaction, ethyl acetate was added to the reaction mixture, and the solution obtained was washed three times with water. The organic layer after water washing is introduced into a large excess of methanol to precipitate a polymer, and the recovered precipitate is dried at 40 ° C. for 12 hours to obtain a methacrylic acid ester copolymer having a pretilt angle developing group ( 10.5 g of BAc-1) was obtained. The weight average molecular weight Mw of the obtained polymer was 16,800.

Synthesis Example 3-2 to Synthesis Example 3-4
Polymers (BAc-2) to (BAc-4) by performing the same operation as in Synthesis Example 3-1 except that types and amounts of the polymerizable unsaturated compound and the carboxylic acid are as described in Table 2 below. I got each. The Mw of each polymer is shown in Table 2 below.

In Table 2, the numerical value of the polymerizable unsaturated compound indicates the use ratio [mol%] of each compound to the total amount of the monomers used for the polymerization. The numerical value of the carboxylic acid indicates the use ratio [mol%] of each compound to the total amount of the epoxy group-containing methacrylic acid ester copolymer used in the reaction. The abbreviation of each compound in Table 2 has the following meanings.
(Polymerizable unsaturated compound)
ECMMA: 3,4-epoxycyclohexylmethyl methacrylate HEMA: 2-hydroxyethyl methacrylate CMI: N-cyclohexyl maleimide ST: styrene BA: n-butyl acrylate (carboxylic acid)
PCHBA: 4- (4-pentylcyclohexyl) benzoic acid OCTBA: 4-octyloxybenzoic acid SACY: succinic acid = 5 = -cholestan-3-yl PCA: 4-phenoxycinnamic acid

<Synthesis of polyamic acid>
Synthesis Example 4-1 Synthesis of Polymer (PAm-1)
52 g (0.10 mol) of 3- (3,5-diaminobenzoyloxy) cholestane as diamine, 11 g (0.10 mol) of p-phenylenediamine and 45 g (0.30 mol) of 2,5-diaminobenzoic acid, and 110 g (0.50 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic acid dianhydride was dissolved in 870 g of NMP and reacted at 60 ° C. for 6 hours. The solution containing polyamic acid (PAm-1) was obtained by adding and diluting NMP and preparing so that a polyamic acid concentration might be 10 weight%. The solution viscosity of this polyamic acid solution was 120 mPa · s.

<Synthesis of Polyimide>
Synthesis Example 5-1 Synthesis of Polymer (PIm-1)
49 g (0.45 mol) of p-phenylenediamine as the diamine and 26 g (0.05 mol) of 3- (3,5-diaminobenzoyloxy) cholestane, and 2,3,5-tricarboxylic acid as the tetracarboxylic acid dianhydride 110 g (0.50 mol) of carboxycyclopentylacetic acid dianhydride was dissolved in 750 g of NMP and reacted at 60 ° C. for 6 hours. A small amount of the resulting polyamic acid solution was taken, NMP was added, and the viscosity was measured with a solution having a solid content concentration of 10% by weight, and it was 58 mPa · s. Next, 1800 g of NMP was added to the obtained polyamic acid solution, 40 g of pyridine and 51 g of acetic anhydride were added, and dehydration ring closure was carried out at 110 ° C. for 4 hours. After the imidization reaction, the solvent in the system was subjected to solvent substitution with fresh NMP to obtain a solution containing about 15% by weight of polyimide (PIm-1) having an imidation ratio of about 50%. A small amount of the obtained polyimide solution was taken, NMP was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 69 mPa · s.

Example 1 VA-Type Liquid Crystal Display Device
(1) Preparation of Liquid Crystal Alignment Agent In 80 parts by weight of the polymer (A-1) obtained in Synthesis Example 1-1 and 20 parts by weight of the polymer (BSi-1) obtained in Synthesis Example 2-1 as a polymer NMP and BC were added to form a solution having a solid concentration of 6.5% by weight and a solvent mixing ratio of NMP: BC = 50: 50 (weight ratio). The solution was sufficiently stirred and then filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent.

(2) Evaluation of printability The liquid crystal aligning agent prepared in the above (1) was applied to a transparent electrode surface of a glass substrate with a transparent electrode formed of an ITO film using a liquid crystal alignment film printing machine (manufactured by Nissha Printing Co., Ltd.). After applying and heating (pre-baking) for 1 minute on a hot plate at 80 ° C. to remove the solvent, heating (post-baking) for 10 minutes on a hot plate at 200 ° C., a coating film having an average film thickness of 0.06 μm Formed. The coated film was observed with a microscope with a magnification of 20 times to examine the presence or absence of printing unevenness and pinholes. In the evaluation, printability “good” when neither printing unevenness nor pinhole was observed, “printability” acceptable when printing unevenness and at least one of pinholes were slightly observed, printing unevenness, and pins When at least one of the holes was frequently observed, the printability was determined as "defective". In this example, neither printing unevenness nor pinholes were observed, and the printability was “good”.

(3) Evaluation of Transmittance The liquid crystal aligning agent prepared above is coated on a quartz substrate using a spin coater and heated (prebaked) on a hot plate at 80 ° C. for 1 minute to remove the solvent, 230 The film was heated (post-baked) in a clean oven at 15 ° C. for 15 minutes under nitrogen to form a coating having an average film thickness of 0.01 μm. About the quartz substrate which formed this coating film, the same kind quartz substrate which does not have a coating film is used as a reference using an ultraviolet visible near-infrared spectrophotometer (made by JASCO Corporation product name "V-670") The absorption spectrum in the ultraviolet and visible light region was measured. The film having a transmittance of 95% or more at a wavelength of 400 nm was regarded as "good", the one having a transmittance of 90% or more and less than 95% as "good", and less than 90% as "defective". The transmittance of the film formed using this alignment agent was 96.2%, which was "good".

(4) Evaluation of Warpage of Substrate A 310 μm-thick 4-inch silicon wafer whose curvature radius has been measured in advance by a thin film stress measurement device KLA-Tencor FLX-2300 was used. The liquid crystal aligning agent prepared above is applied to this silicon wafer respectively using a spin coater and heated (prebaked) on a hot plate at 80 ° C. for 1 minute to remove the solvent, and then on a hot plate at 200 ° C. The film was heated (post-baked) for 10 minutes to form a coating having an average film thickness of 0.08 μm. The curvature radius of the substrate after post-baking was measured, and the warpage stress was determined from the curvature radius before and after the formation of the coating film. The case where the warpage stress was 25 MPa or less was regarded as “good”, the case where it was larger than 25 MPa and less than 40 MPa as “good”, and the case where it was 40 MPa or more as “defective”. As a result, it was a result of "good" in this liquid crystal aligning agent.

(5) Production of VA-Type Liquid Crystal Cell A liquid crystal alignment film printing machine (Nippon Photography printing (stock) was made on the transparent electrode surface of the glass substrate with a transparent electrode (thickness 1 mm) made of ITO film. (Pre-baked) on a hot plate at 80 ° C. for 1 minute, and further heated (post-baked) on a hot plate at 200 ° C. for 60 minutes to give an average coating thickness of 0.08 μm. A film (liquid crystal alignment film) was formed. This operation was repeated to obtain a pair (two sheets) of glass substrates having a liquid crystal alignment film on a transparent conductive film. Next, for one of the pair of substrates, an aluminum oxide sphere-containing epoxy resin adhesive having a diameter of 5.5 μm is applied to the outer edge of the surface having the liquid crystal alignment film, and the pair of substrates is then subjected to the liquid crystal alignment film surface The two were put on top of one another and crimped to cure the adhesive. Next, a nematic liquid crystal (MLC-6608, manufactured by Merck) was filled between a pair of substrates from the liquid crystal injection port, and then the liquid crystal injection port was sealed with an acrylic photo-curing adhesive to manufacture a VA type liquid crystal cell. .

(6) Evaluation of Liquid Crystal Alignment With the liquid crystal cell manufactured in the above (5), the presence or absence of abnormal domain in the change of light and dark when the voltage of 5 V is turned on and off did. In the evaluation, the case where no abnormal domain is observed is regarded as “good” in liquid crystal alignment, the case where a slight abnormal domain is observed is regarded as “liquid crystal alignment”, and the case where many abnormal domains are observed is indicated as liquid crystal alignment It was "bad". In this liquid crystal display element, the liquid crystal alignment was "good".

(7) Evaluation of Voltage Holding Ratio With respect to the liquid crystal cell manufactured in (5) above, after applying a voltage of 5 V at 23 ° C. for an application time of 60 microseconds and a span of 167 milliseconds, 167 milliseconds after release of application. Voltage holding ratio (VHR) was measured. Evaluations were conducted with a VHR of 95% or more as “good”, and 90% or more and less than 95% as “OK” and less than 90% as “poor”. In this liquid crystal display element, the voltage holding ratio was 98.9%, which was an evaluation of “good”. In addition, as a measuring apparatus, Toyo Co., Ltd. make and VHR-1 were used.

(8) Non-uniformity resistance around seal material (bezel non-uniformity resistance)
The liquid crystal cell manufactured in the above (5) was stored for 100 days under the conditions of 25 ° C. and 50% RH, and was then driven at an alternating voltage of 5 V to observe the lighting state. The evaluation is "good" if no luminance difference (more black or more white) is visually recognized around the sealing material, but it is recognized if the luminance difference disappears in 1 to 10 minutes, "OK", 10 minutes The case where the luminance difference was visually recognized even after the lapse was regarded as "defective". As a result, in this liquid crystal display element, no luminance difference was visually recognized around the sealing material, and it was determined that bezel unevenness resistance was "good".

[Examples 2 to 8 and Comparative Examples 1 to 5]
A liquid crystal aligning agent is prepared in the same manner as in Example 1 except that the type and amount of the polymer to be used are changed as shown in Table 3 below, and a liquid crystal aligning agent is used to prepare a liquid crystal aligning agent of 2) The evaluation of (4) was performed. Further, in the same manner as in (5) of Example 1, a VA type liquid crystal cell was manufactured, and (6) to (8) of Example 1 were evaluated. The results are shown in Table 3 below.

  In Table 3, the "amount" of the polyamic acid ester and the other polymer indicates the use ratio [parts by weight] of each polymer to the total amount 100 parts by weight of the polymer component used for preparation of the liquid crystal aligning agent.

  As shown in Table 3, in Examples 1 to 8, all of the warping of the substrate, the liquid crystal alignment property, and the voltage holding ratio were evaluated as “good” or “good”. From this, it was found that in Examples 1 to 8, the warpage characteristics of the substrate can be improved while improving the liquid crystal alignment and the voltage holding ratio. Moreover, in Examples 1 to 8, the printability and transmittance of the coating film and the bezel unevenness resistance in the liquid crystal display element were also evaluated as “good” or “good”, and various characteristics were balanced. On the other hand, in Comparative Examples 1 to 5, any one of the voltage holding ratio and the warpage characteristic of the substrate was “defective”. From these things, according to the liquid crystal aligning agent containing partial structure (c-1) and partial structure (c-2) in a polymer component, in addition to printability, membrane permeability, and curvature suppression of a substrate, it is obtained. It was found that the liquid crystal alignment of the liquid crystal display element, the voltage holding characteristic and the bezel unevenness resistance can be improved in a well-balanced manner.

Example 9 Retardation Film
(1) Preparation of Liquid Crystal Alignment Agent As a polymer, 100 parts by weight of the polymer (A-1) obtained in Synthesis Example 1-1, and 10 parts by weight of the polymer (BSi-4) obtained in Synthesis Example 2-4 Was dissolved in a mixed solvent of NMP and BC (NMP: BC = 50: 50 (weight ratio)) to give a solution having a solid content concentration of 3.5% by weight. The solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent.

(2) Production of Retardation Film The liquid crystal aligning agent prepared above is coated on one surface of a TAC film as a substrate using a bar coater, and baked at 120 ° C. for 2 minutes in an oven to have a film thickness of 100 nm. A coating was formed. Then, 10 mJ / cm ² of polarized ultraviolet light containing a 313 nm bright line was irradiated perpendicularly to the substrate normal using the Hg-Xe lamp and a Glan-Taylor prism. Next, after filtering the polymerizable liquid crystal (RMS03-013C, manufactured by Merck) with a filter with a pore diameter of 0.2 μm, the polymerizable liquid crystal is coated on the coating after light irradiation by a bar coater to obtain a polymerizable liquid crystal A coating was formed. After baking for 1 minute in an oven adjusted to a temperature 50 ° C., using an Hg-Xe lamp with ultraviolet 1,000 mJ / cm ² of unpolarized light irradiated from a direction perpendicular to the coated surface containing the 365nm emission lines A retardation film was produced by curing the polymerizable liquid crystal to form a liquid crystal layer.

(3) Evaluation of Liquid Crystal Alignment Property The liquid crystal alignment property of the retardation film produced in (2) above was observed by visual observation under crossed nicols and the presence or absence of abnormal domain with a polarization microscope (2.5 times magnification) Photo-orientation) was evaluated. In the evaluation, when the alignment was visually observed to be good and the abnormal domain was not observed by the polarization microscope, the liquid crystal alignment "good", the abnormal domain was not observed visually but the abnormality was observed by the polarization microscope The case where the domain was observed was regarded as liquid crystal alignment "good", and the case where the abnormal domain was observed visually and with a polarization microscope was regarded as liquid crystal alignment "bad". As a result, this retardation film was evaluated as liquid crystal alignment "good".

(4) Adhesion Using the retardation film produced in (2) above, the adhesion of the coating film formed with the liquid crystal aligning agent to the substrate was evaluated. First, cuts were made from the surface on the liquid crystal layer side of the retardation film with a cutter knife using equally spaced spacers with guides, to form 10 × 10 grid patterns in the range of 1 cm × 1 cm. The depth of each cut was made to reach from the surface of the liquid crystal layer to the middle of the substrate thickness. Next, cellophane tape was adhered to cover the entire surface of the lattice pattern, and then the cellophane tape was peeled off. The adhesion was evaluated by observing the cut portion of the lattice pattern after peeling by visual observation under cross nicol. In the evaluation, the adhesion is "good" when peeling is not confirmed in the portion along the cut line and in the crossing portion of the lattice pattern, the number of lattices in which peeling is observed in the above portion is the number of whole lattice patterns. On the other hand, when the ratio is less than 15%, the adhesiveness is "good", and when the number of lattices in which peeling is observed in the above part is 15% or more with respect to the total number of grating patterns, the adhesiveness is "bad". went. As a result, this retardation film had good adhesion "good".

Claims (11)

It is selected from the group consisting of structures derived from a monomer having a carbon-carbon unsaturated bond - polymer having a partial structure represented by the following formula (1) (c-1) and (A), a siloxane structure and a polymerizable carbon Liquid crystal aligning agent containing the polymer (B) which has at least 1 type of partial structure (c-2).

(In the formula (1), ^{R 1} and ^{R 2} are each independently an alkyl group having 1 to 12 carbon atoms, .X ^{1 R 3} and ^{R 4} is water MotoHara child alicyclic tetracarboxylic It is a tetravalent group having a partial structure formed by removing two acid anhydride groups possessed by acid dianhydride , and Y ¹ is a divalent group derived from an aromatic diamine .) The liquid crystal aligning agent according to claim 1 , wherein the polymer (B) is a polymer having an epoxy group. The liquid crystal aligning agent of Claim 1 or 2 in which the said polymer (B) is a polymer which has a hydroxyl group. The blending ratio of the polymer (A) and the polymer (B) is, in weight ratio of the polymer (A) / polymer (B) is 20 / 80-98 / 2, of claims 1 to 3, The liquid crystal aligning agent as described in any one. The polymerizable carbon - monomer having a carbon-carbon unsaturated bond include (meth) acrylic compound is at least one compound selected from the group consisting of aromatic vinyl compounds and maleimide compounds, any of claims 1-4 one The liquid crystal aligning agent as described in a term. Said X ¹ is bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid 2: 3,5: 6-dianhydride, 1,2,3,4-cyclobutane tetracarboxylic acid Dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 5- (2,5-dioxotetrahydrofuran-3-yl) -8-methyl-3a, 4,5,9b-tetrahydronaphtho [1 , 2-c] furan-1,3-dione, 5- (2,5-dioxotetrahydrofuran-3-yl) -3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1, 3-dione, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic acid 2: 4,6: 8-dianhydride, and 1,2,4,5-cyclohexanetetracarboxylic acid compound of one selected from the group consisting of dianhydrides by Li Cheng group The liquid crystal aligning agent as described in any one of Claims 1-5 which is a tetravalent group which has a partial structure formed by removing two acid anhydride groups which it has. At least one selected from the group consisting of a polymer (A) having a partial structure (c-1) represented by the following formula (1) and a structure derived from a siloxane structure and a monomer having a polymerizable carbon-carbon unsaturated bond The liquid crystal aligning agent prepared by mix | blending the polymer (B) which has 1 type of partial structure (c-2).

(In the formula (1), ^{R 1} and ^{R 2} are each independently an alkyl group having 1 to 12 carbon atoms, .X ^{1 R 3} and ^{R 4} is water MotoHara child alicyclic tetracarboxylic It is a tetravalent group having a partial structure formed by removing two acid anhydride groups possessed by acid dianhydride , and Y ¹ is a divalent group derived from an aromatic diamine .) Liquid crystal alignment film formed by using the liquid crystal aligning agent according to any one of claims 1-7. The liquid crystal display element which comprises the liquid crystal aligning film of Claim 8 . The retardation film which comprises the liquid crystal aligning film of Claim 8 . Forming a claim 1-7 coated film by applying onto a substrate the liquid crystal alignment agent according to any one of the the steps of the coating film irradiation, on the coating film after irradiation the light And (ii) applying and curing a polymerizable liquid crystal on the film.