JP6375789B2 - Liquid crystal aligning agent, liquid crystal aligning film, liquid crystal display element, retardation film and method for producing the same - Google Patents

Description

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display device, about the retardation film and a manufacturing how.

  Conventionally, as a liquid crystal display element, various drive systems having different electrode structures, physical properties of liquid crystal molecules to be used, manufacturing processes, and the like 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 for the liquid crystal alignment film, polyamic acid or polyimide is generally used from the viewpoints of various properties such as heat resistance, mechanical strength, and affinity with liquid crystal.

  In recent years, liquid crystal display elements are used not only for display terminals such as personal computers as in the past, but also for various applications such as liquid crystal televisions, car navigation systems, mobile phones, smartphones, and information displays. . Against this background, demands for higher performance of liquid crystal display elements are increasing, and liquid crystal alignment films are required to be able to further improve various characteristics required for liquid crystal display elements. Various liquid crystal aligning agents for obtaining such liquid crystal aligning films, polymers blended in the liquid crystal aligning agents, and monomers for obtaining the polymers have been proposed (for example, Patent Documents 1 and 2). reference).

  Patent Document 1 does not have polar groups such as 1,2-bis (4- (4-aminobenzyl) phenyl) ethane and 1,6-bis (4- (4-aminobenzyl) phenyl) hexane. It is disclosed that a polyimide obtained by a reaction between a diamine and tetracarboxylic dianhydride is used as a polymer component of a liquid crystal aligning agent. In addition, in Patent Document 2, it is obtained by reacting 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,5-bis [4- (4-aminophenoxy) phenoxy] pentane in Examples. It is disclosed that the polyamic acid obtained is used as a polymer component of a liquid crystal aligning agent.

  In addition, various optical materials are used for liquid crystal display elements. Above all, retardation films eliminate the object of viewing color dependency and the viewing angle dependency that the display color and contrast ratio change depending on the visual direction. It is used for the purpose. 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. It has been. In recent years, a liquid crystal alignment film in a retardation film has been produced by using a photo-alignment method that imparts liquid crystal alignment ability by irradiating a radiation-sensitive organic thin film formed on the substrate surface with polarized or non-polarized radiation. Various liquid crystal aligning agents for retardation films for producing a liquid crystal aligning film by such a method have been proposed (for example, see Patent Document 3).

  As a method for producing a retardation film on an industrial scale, a roll-to-roll method has been proposed (for example, see Patent Document 4). In this method, a film is unwound from a wound body of a long base film, a liquid crystal alignment film is formed on the unwound film, and a polymerizable liquid crystal is applied and cured on the liquid crystal alignment film. It is the method of performing the process and the process which laminates | stacks a protective film as needed in the continuous process, and collect | recovering the film after passing through these processes as a wound body.

Japanese Patent No. 3658798 International Publication No. 2004/053583 JP 2012-37868 A JP 2000-86786 A

  However, when the polyimide described in Patent Document 1 is used as the polymer component of the liquid crystal aligning agent, the liquid crystal aligning agent tends to have poor applicability to the substrate. Further, when a liquid crystal alignment film of an FFS type liquid crystal display element is produced using this liquid crystal aligning agent, the pretilt angle becomes too high and the viewing angle characteristics are inferior. In the liquid crystal display element using the liquid crystal aligning agent containing the polyamic acid of the said patent document 2, it will be inferior to a voltage holding characteristic and heat resistance.

  In addition, for the retardation film, by adopting the above roll-to-roll method, it can be easily produced on an industrial scale, but when the adhesion between the liquid crystal alignment film and the substrate film is insufficient, When the film is used as a wound body after completion of the process, the liquid crystal alignment film may be peeled off from the substrate film. In such a case, there may arise a problem that the product yield decreases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a liquid crystal aligning agent for forming a liquid crystal aligning film capable of suitably expressing various characteristics required for a liquid crystal display element. Another object of the present invention is to provide a liquid crystal aligning agent for forming a liquid crystal aligning film for a retardation film having good liquid crystal alignment and good adhesion to a substrate.

  As a result of intensive studies to achieve the above-described problems of the prior art, the present inventors have found that polyamic acid, polyamic acid ester and polyimide obtained by polycondensation of a diamine having a specific structure and a tetracarboxylic acid derivative. It has been found that the above problems can be solved by including at least one of the polymers, and the present invention has been completed. Specifically, the present invention provides the following liquid crystal aligning agent, liquid crystal alignment film, liquid crystal display element, retardation film, production method thereof, polymer and compound.

  In one aspect, the present invention provides at least one tetracarboxylic acid derivative selected from the group consisting of a tetracarboxylic dianhydride, a tetracarboxylic acid diester compound, and a tetracarboxylic acid diester dihalide, represented by the following formula (1): Provided is a liquid crystal aligning agent containing at least one polymer (P) selected from the group consisting of a polyamic acid, a polyamic acid ester and a polyimide obtained by reacting a diamine containing such a compound.

（式（１）中、Ｒ^Ａは、炭素数１〜３０の炭化水素基の炭素−炭素結合間及び当該炭化水素基と隣り合う位置の少なくともいずれかに、酸素原子又は硫黄原子を有する２価の基であり、当該炭化水素基が有する水素原子の少なくとも１つがハロゲン原子で置換されていてもよい。Ｘ^１及びＸ^２は、それぞれ独立に、単結合、酸素原子、硫黄原子又は２価の有機基である。但し、Ｘ^１及びＸ^２が酸素原子であり、かつＲ^Ａが−Ｏ−Ｒ^１−Ｏ−（Ｒ^１は炭素数１〜１８のアルカンジイル基である。）の場合、前記テトラカルボン酸誘導体が１，２，３，４−シクロブタンテトラカルボン酸二無水物である場合を除く。）

(In the formula (1), R ^A is a divalent having an oxygen atom or a sulfur atom at least at any position between the carbon-carbon bond of the hydrocarbon group having 1 to 30 carbon atoms and the position adjacent to the hydrocarbon group. And at least one hydrogen atom of the hydrocarbon group may be substituted with a halogen atom, X ¹ and X ² are each independently a single bond, an oxygen atom, a sulfur atom or a divalent group. An organic group, provided that when X ¹ and X ² are oxygen atoms and R ^A is —O—R ¹ —O— (R ¹ is an alkanediyl group having 1 to 18 carbon atoms), (Except when the tetracarboxylic acid derivative is 1,2,3,4-cyclobutanetetracarboxylic dianhydride)

  In another aspect, the present invention provides a liquid crystal alignment film formed using the liquid crystal alignment agent. Moreover, a liquid crystal display element and retardation film provided with the said liquid crystal aligning film are provided. Furthermore, in another aspect, the step of coating the liquid crystal aligning agent on a substrate to form a coating film, the step of irradiating the coating film with light, and the polymerization on the coating film after the light irradiation And a step of applying and curing a liquid crystal. Furthermore, at least one selected from the group consisting of the compound represented by the above formula (1), a diamine containing the compound, a tetracarboxylic dianhydride, a tetracarboxylic diester compound, and a tetracarboxylic diester dihalide. Provided is a polymer obtained by reacting with a tetracarboxylic acid derivative.

  Liquid crystal capable of suitably exhibiting various properties required for a liquid crystal display element by using a liquid crystal aligning agent containing a polymer obtained by the reaction of a diamine represented by the above formula (1) and a tetracarboxylic acid derivative. An alignment film can be formed. Moreover, according to the liquid crystal aligning agent of this invention, a high quality liquid crystal display element can be manufactured. Furthermore, the liquid crystal alignment film obtained using the liquid crystal aligning agent of this invention has favorable adhesiveness with respect to a board | substrate. Therefore, even when this is stored as a wound body, the liquid crystal alignment film and the substrate are difficult to peel off, and thus, for example, in the production of a retardation film, it is possible to suppress a decrease in product yield.

The schematic block diagram of a FFS type liquid crystal display element. The plane schematic diagram of a top electrode. (A) is a top view of a top electrode, (b) is the elements on larger scale of a top electrode.

  The liquid crystal aligning agent of this invention contains the at least 1 sort (s) of polymer (P) chosen from the group which consists of polyamic acid, polyamic acid ester, and a polyimide, and contains another component as needed. Below, each component contained in the liquid crystal aligning agent of this invention and the other component arbitrarily mix | blended as needed are demonstrated.

<Polymer (P): Polyamic acid>
The polyamic acid (hereinafter also referred to as polyamic acid (P)) as the polymer (P) in the present invention can be obtained by reacting a tetracarboxylic dianhydride and a diamine.

[Tetracarboxylic dianhydride]
Examples of tetracarboxylic dianhydrides used to synthesize polyamic acid (P) include aliphatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, and aromatic tetracarboxylic dianhydrides. Can be mentioned. Specific examples thereof include aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride;
Examples of the alicyclic tetracarboxylic dianhydride include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4, 5,9b-Hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b- Hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [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- No 1,2-dicarboxylic acid 3,5,6-tricarboxy-2-carboxymethylnorbornane-2: 3,5: 6-dianhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2 : 4,6: 8-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone, cyclohexanetetracarboxylic dianhydride Etc .;
Examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride and the like; respectively, and tetracarboxylic dianhydrides described in JP 2010-97188 A can be used. In addition, the said tetracarboxylic dianhydride can be used individually by 1 type or in combination of 2 or more types.

Examples of tetracarboxylic dianhydrides used in the synthesis include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4. , 5,9b-Hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b -Hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [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 Anhydride, 3,5,6-tricarboxy-2-carboxy-methyl-norbornane -2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^{2, 6]} Undecane-3,5,8,10-tetraone, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic dianhydride, ethylenediaminetetraacetic acid dianhydride, and pyromellitic dianhydride It is preferable to include at least one selected from the group consisting of products. Moreover, it is preferable that an alicyclic tetracarboxylic dianhydride is included from a viewpoint of transparency and solubility in a solvent, and it is preferable that an aromatic tetracarboxylic dianhydride is included from the viewpoint of electrical characteristics.

[Diamine]
The diamine used for synthesizing the polyamic acid (P) includes a compound represented by the above formula (1).

R ^A in the above formula (1) is a divalent having an oxygen atom or a sulfur atom at least between the carbon-carbon bond of the hydrocarbon group having 1 to 30 carbon atoms and at a position adjacent to the hydrocarbon group. It is a group. Here, the “hydrocarbon group” in this specification means a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. The “chain hydrocarbon group” means a linear or branched hydrocarbon group composed of only a chain structure without including a cyclic structure in the main chain, and may be saturated or unsaturated. The “alicyclic hydrocarbon group” means a hydrocarbon group that includes only an alicyclic hydrocarbon structure as a ring structure and does not include an aromatic ring structure. However, it is not necessary to be comprised only by the structure of an alicyclic hydrocarbon, The thing which has a chain structure in the part is also included. “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 part thereof may include a chain structure or an alicyclic hydrocarbon structure.

Specific examples of the hydrocarbon group having 1 to 30 carbon atoms include a chain hydrocarbon group such as a methylene group, an ethylene group, a propanediyl group, a butanediyl group, a pentanediyl group, a hexanediyl group, a heptanediyl group, an octanediyl group, Nonanediyl group, decanediyl group, dodecanediyl group, tetradecanediyl group, pentadecanediyl group, hexadecanediyl group, octadecanediyl group and the like can be mentioned, and these may be linear or branched. The alicyclic hydrocarbon group includes, for example, a group obtained by removing two hydrogen atoms from cyclopentane, cyclohexane, methylcyclohexane, ethylcyclohexane, propylcyclohexane, pentylcyclohexane, dimethylcyclohexane, etc .; as an aromatic hydrocarbon group Can include, for example, groups obtained by removing two hydrogen atoms from benzene, toluene, xylene, ethylbenzene, propylbenzene, pentylbenzene and the like; The hydrocarbon group in ^RA preferably has a divalent chain hydrocarbon group, more preferably a divalent chain hydrocarbon group, and particularly preferably an alkanediyl group.
Note that at least one hydrogen atom of the hydrocarbon group in R ^A may be substituted with a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

The number (total number) of oxygen atoms and sulfur atoms possessed by ^RA is not particularly limited, and can be appropriately selected depending on the number of carbon atoms of ^RA from the viewpoint of reducing the pretilt and improving the solubility of the polymer. Preferably it is 1-5, More preferably, it is 1-3. In addition, when R ^A has a plurality of these heteroatoms (oxygen atoms, sulfur atoms), it may have only one of oxygen atoms and sulfur atoms, or two of them. Also good.
The position where the oxygen atom or sulfur atom is introduced may be between the carbon-carbon bonds of the hydrocarbon group, may be adjacent to the hydrocarbon group, or both. Incidentally, "carbons of the hydrocarbon group - carbon-carbon bond" with the position of the heteroatom ^{X a} is ^"-R 10 ^-X a ^{-R 11} -" a ^{(where, R 10} and ^{R 11} represents a hydrocarbon group) a case, a "position adjacent to the hydrocarbon group", the position of the heteroatom ^{X a "*} -X a ^{-R 12} -" ^{(wherein, R 12} is a hydrocarbon group, "*" in ^{R a} It means a case where it becomes a bond with a benzene ring to be bonded.

X ¹ and X ² are each independently a single bond, an oxygen atom, a sulfur atom or a divalent organic group. Here, as the “divalent organic group” in X ¹ and X ² , for example, a substituted or unsubstituted alkanediyl group, a substituted or unsubstituted alkenediyl group, a carbonyl group, an ester group (—COO—), an amide group (—CO—NH—) and the like can be mentioned as preferred specific examples. The alkanediyl group of X ¹ and X ² preferably has 1 to 10 carbon atoms, more preferably 1 to 5 and even more preferably 1 to 3. The alkenediyl group preferably has 2 to 10 carbon atoms, more preferably 2 to 5 carbon atoms, and still more preferably 2 to 3 carbon atoms. In addition, examples of the substituent introduced into the alkanediyl group and alkenediyl group include an oxygen atom (—O—), a sulfur atom (—S—), and a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom, etc.). And a hydroxyl group.
X ¹ and X ² are preferably an oxygen atom, an ester group, an amide group, an alkanediyl group having 1 to 10 carbon atoms, or an alkenediyl group having 2 to 10 carbon atoms, preferably an oxygen atom, an amide group, carbon It is more preferably an alkanediyl group having 1 to 5 carbon atoms or an alkenediyl group having 2 to 5 carbon atoms, and particularly preferably an oxygen atom, an amide group, a methylene group, an ethylene group or a vinylene group.

（式（１−１）中、Ｒ^２は、炭素数１〜３０の２価の炭化水素基であり、Ｘ^３は、酸素原子又は硫黄原子であり、Ｘ^４は、単結合、酸素原子又は硫黄原子である。Ｘ^１及びＸ^２は上記式（１）と同義である。） Among the above, the compound represented by the above formula (1) is preferably a compound represented by the following formula (1-1).

(In the formula (1-1), ^{R 2} is a divalent hydrocarbon group having 1 to 30 carbon atoms, ^{X 3} is an oxygen atom or a sulfur atom, ^{X 4} represents a single bond, an oxygen atom or (It is a sulfur atom. X ¹ and X ² are synonymous with the above formula (1).)

As a specific example of R ² in the above formula (1-1), the description of the hydrocarbon group having 1 to 30 carbon atoms of R ^{A in} the above formula (1) can be applied. R ² is preferably a divalent chain hydrocarbon group, and more preferably an alkanediyl group. The alkanediyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 11 carbon atoms, and still more preferably 1 to 8 carbon atoms.
X ³ is an oxygen atom or a sulfur atom, and is preferably an oxygen atom. X ⁴ is a single bond, an oxygen atom or a sulfur atom, and preferably a single bond or an oxygen atom.

Preferable specific examples of the compound represented by the formula (1) include, for example, compounds represented by the following formulas (DA-1) to (DA-16).

From the viewpoint of sufficiently obtaining the effects of the present invention, the use ratio of the compound represented by the above formula (1) is in the range of 1 to 100 mol% with respect to the total amount of diamine used for the synthesis of polyamic acid. It is preferable. About a lower limit, More preferably, it is 5 mol% or more, More preferably, it is 15 mol% or more, Most preferably, it is 20 mol% or more. The compounds represented by the above formula (1) can be used singly or in combination of two or more.
In the compound represented by the above formula (1), the group “R ^A ” between two benzene rings is a hydrocarbon group having an oxygen atom or a sulfur atom. It is presumed that the coalescence increases the solubility of the polymer due to the improvement in polarity, and improves the applicability of the liquid crystal aligning agent to the substrate. Further, it is presumed that the rubbing stretchability is improved by improving the rotational property of the molecules, and this makes it possible to realize a low pretilt (an improved viewing angle) of the liquid crystal alignment film. The compound represented by the above formula (1) is a polymer capable of forming a liquid crystal alignment film having various properties such as liquid crystal alignment property, voltage holding property, and heat resistance by condensation polymerization with tetracarboxylic acid anhydride or the like. Both have the same action in that they can be obtained. Accordingly, even those not described in the following examples can be used in the present invention.

[Synthesis of Compound Represented by Formula (1) above]
The compound represented by the above formula (1) can be synthesized by appropriately combining organic chemistry methods. As an example, a dinitro intermediate having a nitro group is synthesized in place of the primary amino group in the above formula (1), and then the nitro group of the obtained dinitro intermediate is converted to an amino group using an appropriate reduction system. The method of making it.

The method for synthesizing the dinitro intermediate can be appropriately selected depending on the target compound. As an example, for example, when X ¹ and X ² are oxygen atoms, a dihydro compound represented by HO—Ph—R ^A —Ph—OH (Ph is a phenylene group) is synthesized, and the dihydro compound and halogenated nitrobenzene are synthesized. It can obtain by making it react. When X ¹ and X ² are methylene groups, a compound represented by Bz—R ^A —Bz (Bz is a phenyl group) is reacted with nitrobenzoic acid chloride, and the resulting reaction product has a carbonyl group. Can be obtained by reducing to a methylene group. When X ¹ and X ² are ester groups, they can be obtained by reacting the dihydro compound with nitrobenzoic acid chloride.
The reduction reaction of the dinitro intermediate can be preferably carried out in an organic solvent using a catalyst such as palladium carbon, platinum oxide, zinc, iron, tin, nickel or the like. Examples of the organic solvent used here include ethyl acetate, toluene, tetrahydrofuran, and alcohols. However, the synthesis procedure of the compound represented by the above formula (1) is not limited to the above method.

[Other diamines]
As the diamine used for the synthesis of the polyamic acid (P), the compound represented by the above formula (1) may be used alone, but together with the compound represented by the above formula (1), Other diamines may be used in combination.
Here, examples of the other diamine include aliphatic diamine, alicyclic diamine, aromatic diamine, and diaminoorganosiloxane. Specific examples of these diamine compounds include aliphatic diamines such as m-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, and 1,3-bis (aminomethyl) cyclohexane. Alicyclic diamines such as 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、ｎ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を； Examples of aromatic diamines include p-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl, 2,7-diaminofluorene, 4,4′-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl ] Propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane 4,4 ′-(p-phenylenediisopropylidene) bisaniline, 4,4 ′-(m-phenylenediisopropylene Riden) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diamino Pyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N , N′-bis (4-aminophenyl) -benzidine, N, N′-bis (4-aminophenyl) -N, N′-dimethylbenzidine, 1,4-bis- (4-aminophenyl) -piperazine, 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-indene-5-amine, 1- (4-aminophen 2) -2,3-dihydro-1,3,3-trimethyl-1H-indene-6-amine, 3,5-diaminobenzoic acid, cholestanyloxy-3,5-diaminobenzene, cholestenyloxy-3, 5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, cholestanyl 3,5-diaminobenzoate, cholestenyl 3,5-diaminobenzoate, 3,5-diamino Lanostanyl benzoate, 3,6-bis (4-aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 4- (4′-trifluoromethoxybenzoyloxy) cyclohexyl-3,5- Diaminobenzoate, 4- (4′-trifluoromethylbenzoyloxy) cyclohexyl-3,5-di Aminobenzoate, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4-butylcyclohexane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4-heptylcyclohexane, , 1-bis (4-((aminophenoxy) methyl) phenyl) -4-heptylcyclohexane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4- (4-heptylcyclohexyl) cyclohexane, 2,4-diamino-N, N-diallylaniline, 4-aminobenzylamine, 3-aminobenzylamine, 1,3-diamino-4-octadecyloxybenzene, 3- (3,5-diaminobenzoyloxy) cholestane, 3,6-bis (4-aminobenzoyloxy) cholestane and the following formula (D-1)

(In Formula (D-1), X ^I and X ^II are each independently 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 n is 0 or 1, provided that a and b are not 0 at the same time.)
A compound represented by:

  Examples of the diaminoorganosiloxane include 1,3-bis (3-aminopropyl) -tetramethyldisiloxane, and the like, and diamines described in JP 2010-97188 A can be used.

Examples of the divalent group represented by “—X ^I — (R ^I —X ^II ) _n —” in the formula (D-1) include an alkanediyl group having 1 to 3 carbon atoms, * —O—, * —COO— or * —O—C ₂ H ₄ —O— (however, a bond marked with “*” is bonded to a diaminophenyl group) is preferred.
Specific examples of the group “—C _c H _{2c + 1} ” include, for example, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group. Group, n-nonyl group, n-decyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group Group, n-eicosyl group and the like. The two amino groups in the diaminophenyl group are preferably in the 2,4-position or 3,5-position with respect to other groups.

なお、ポリアミック酸（Ｐ）の合成に使用するジアミンは、上記のものを１種単独で又は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 compound represented by the formula (D-1) include compounds represented by the following formulas (D-1-1) to (D-1-4). .

In addition, the diamine used for the synthesis | combination of polyamic acid (P) can use the said thing individually by 1 type or in combination of 2 or more types.

  When using the liquid crystal aligning agent of this invention for manufacture of a TN type, STN type, or vertical alignment type liquid crystal display element, as said other diamine, group which can provide pretilt angle expression ability with respect to a coating film (henceforth "" It is also preferable to include a diamine having a “pretilt angle imparting group”. Examples of the pretilt angle-providing group include alkyl groups having 4 to 20 carbon atoms, fluoroalkyl groups having 4 to 20 carbon atoms, alkoxy groups having 4 to 20 carbon atoms, groups having a steroid skeleton having 17 to 51 carbon atoms, and polycyclic rings. Examples thereof include a group having a structure.

Specific examples of the diamine having a pretilt angle imparting group include, for example, dodecaoxy-2,4-diaminobenzene, tetradecaoxy-2,4-diaminobenzene, octadecaoxy-2,4-diaminobenzene, and tetradecaoxy-2. , 5-diaminobenzene, pentadecaoxy-2,5-diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, Cholestanyl 3,5-diaminobenzoate, cholestenyl 3,5-diaminobenzoate, lanostannyl 3,5-diaminobenzoate, 3,6-bis (4-aminobenzoyloxy) cholestane, 4- (4′-trifluoromethoxy) Benzyloxy) cyclohexyl-3,5-diaminobenzoe 4- (4′-trifluoromethylbenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4-heptylcyclohexane, 1, 1-bis (4-((aminophenoxy) methyl) phenyl) -4-heptylcyclohexane, a diamine represented by the above formula (D-1), and the like can be given. In addition, the said diamine can be used individually by 1 type or in combination of 2 or more types.
When using a diamine having a pretilt angle imparting group, the proportion used is preferably 5 mol% or more, preferably 10 mol% or more, based on the total diamine, from the viewpoint of developing sufficiently high pretilt angle characteristics. It is more preferable. In addition, the upper limit of the use ratio is not particularly limited, but is preferably 99 mol% or less with respect to the total diamine from the viewpoint of not impairing the effect of the use of the compound represented by the formula (1). More preferably, it is 95 mol% or less.

[Molecular weight regulator]
When synthesizing the polyamic acid (P), a terminal-modified polymer may be synthesized using an appropriate molecular weight regulator together with the tetracarboxylic dianhydride and diamine as described above. By using such a terminal-modified polymer, the coating property (printability) of the liquid crystal aligning agent can be further improved without impairing the effects of the present invention.

Examples of molecular weight regulators include acid monoanhydrides, monoamine compounds, monoisocyanate compounds, and the like. Specific examples thereof include acid monoanhydrides such as maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic. Acid anhydrides, n-hexadecyl succinic anhydride, etc .; monoamine compounds such as aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, Examples of the monoisocyanate compound include n-dodecylamine and n-octadecylamine; for example, phenyl isocyanate and naphthyl isocyanate.
The use ratio of the molecular weight regulator is preferably 20 parts by weight or less, and more preferably 10 parts by weight or less with respect to 100 parts by weight of the total of the tetracarboxylic dianhydride and diamine used.

[Synthesis of polyamic acid]
The ratio of the tetracarboxylic dianhydride and the diamine used for the synthesis reaction of the polyamic acid (P) is such that the acid anhydride group of the tetracarboxylic dianhydride is 0 with respect to 1 equivalent of the amino group of the diamine. A ratio of 2 to 2 equivalents is preferable, and a ratio of 0.3 to 1.2 equivalents is more preferable. The synthesis reaction of polyamic acid (P) is preferably performed in an organic solvent. The reaction temperature at this time is preferably −20 ° C. to 150 ° C., 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 include aprotic polar solvents, phenol solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. Specific examples of these organic solvents include aprotic polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, Hexamethylphosphortriamide and the like; phenolic solvents such as phenol, m-cresol, xylenol, halogenated phenol and the like;
Examples of alcohols include methanol, ethanol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, and ethylene glycol monomethyl ether; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; and esters such as ethyl lactate, Butyl lactate, methyl acetate, ethyl acetate, butyl acetate, diethyl malonate, isoamyl propionate, isoamyl isobutyrate and the like; ethers such as diethyl ether, diisopentyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, Ethylene glycol-n-propyl ether, ethylene glycol-n-butyl ether, ethylene glycol dimethyl ether , Ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, tetrahydrofuran, etc .; halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, etc .; , Hexane, heptane, octane, benzene, toluene, xylene 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 of organic solvents), or one or more selected from the first group of organic solvents, It is preferable to use a mixture with one or more selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons (second group organic solvent). 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 with respect to the total amount of the first group organic solvent and the second group organic solvent. % Or less, more preferably 30% by weight or less. The amount of organic solvent used (α) is such that the total amount (β) of tetracarboxylic dianhydride and diamine is 0.1 to 50% by weight based on the total amount of the reaction solution (α + β). It is preferable that

  As described above, a reaction solution obtained by dissolving the polyamic acid (P) is obtained. This reaction solution may be used as it is for the preparation of the liquid crystal aligning agent, may be used for the preparation of the liquid crystal aligning agent after isolating the polyamic acid contained in the reaction solution, or the isolated polyamic acid was purified. You may use for preparation of a liquid crystal aligning agent. When polyamic acid is dehydrated and cyclized into a polyimide, the above reaction solution may be directly subjected to dehydration and cyclization reaction, or may be subjected to dehydration and cyclization reaction after isolating the polyamic acid contained in the reaction solution. Alternatively, the isolated polyamic acid may be purified and then subjected to a dehydration ring closure reaction. Isolation and purification of the polyamic acid can be performed according to known methods.

<Polymer (P): Polyamic acid ester>
The polyamic acid ester (hereinafter also referred to as polyamic acid ester (P)) as the polymer (P) of the present invention is, for example, [I] a polyamic acid (P) obtained by the above synthesis reaction and a hydroxyl group-containing compound. , A method of synthesizing by reacting a halide, an epoxy group-containing compound, etc., [II] a method of reacting a tetracarboxylic acid diester compound and a diamine, and [III] reacting a tetracarboxylic acid diester dihalide and a diamine. It can be obtained by the method. In the present specification, the “tetracarboxylic acid diester compound” means a compound in which two of the four carboxyl groups of tetracarboxylic acid are esterified and the remaining two are carboxyl groups. “Tetracarboxylic acid diester dihalide” means a compound in which two of the four carboxyl groups of tetracarboxylic acid are esterified and the remaining two are halogenated.

  Here, examples of the hydroxyl group-containing compound used in the method [I] include alcohols such as methanol, ethanol and propanol; phenols such as phenol and cresol. Examples of the halide include methyl bromide, ethyl bromide, stearyl bromide, methyl chloride, stearyl chloride, 1,1,1-trifluoro-2-iodoethane and the like, and as an epoxy group-containing compound, Examples thereof include propylene oxide. The tetracarboxylic acid diester compound used in the method [II] can be obtained, for example, by ring-opening the tetracarboxylic dianhydride exemplified in the synthesis of the polyamic acid (P) using the above alcohols. . The tetracarboxylic acid diester dihalide used in the method [III] can be obtained, for example, by reacting the tetracarboxylic acid diester compound obtained as described above with an appropriate chlorinating agent such as thionyl chloride. . The diamine used in the methods [II] and [III] contains the compound represented by the above formula (1). Moreover, you may use the said other amine as needed. The polyamic acid ester may have only an amic acid ester structure, or may be a partially esterified product in which an amic acid structure and an amic acid ester structure coexist.

<Polymer (P): Polyimide>
The polyimide (hereinafter also referred to as “polyimide (P)”) as the polymer (P) contained in the liquid crystal aligning agent of the present invention is a polyamic acid (P) synthesized as described above and dehydrating and ring-closing. Can be obtained by imidization.

  The polyimide (P) may be a completely imidized product obtained by dehydrating and ring-closing all of the amic acid structure that the polyamic acid that is the precursor of the polyimide (P), and part of the amic acid structure and the amic acid ester structure May be a partially imidized product in which at least one of an amic acid structure and an amic acid ester structure and an imide ring structure coexist. The polyimide (P) is preferably 30% or more, more preferably 40 to 99%, and still more preferably 50 to 99% in that the voltage holding ratio can be increased. . This imidation ratio represents the ratio of the number of imide ring structures to the total of the number of amic acid structures of polyimide, the number of amic acid ester structures, and the number of imide ring structures in percentage. Here, a part of the imide ring may be an isoimide ring.

  The polyamic acid is preferably dehydrated and closed by heating the polyamic acid, or by dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring-closing catalyst to the solution, and heating the solution as necessary. . Of these, the latter method is preferred.

  In the method of imidizing a polyamic acid solution by adding a dehydrating agent and a dehydrating ring-closing catalyst, acid anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used as the dehydrating agent. It is preferable that the usage-amount of a dehydrating agent shall be 0.01-20 mol with respect to 1 mol of the amic acid structure of a polyamic acid. As the dehydration ring closure catalyst, for example, tertiary amines such as pyridine, collidine, lutidine, triethylamine and the like can be used. It is preferable that the usage-amount of a dehydration ring-closing catalyst shall be 0.01-10 mol with respect to 1 mol of dehydrating agents to be used. Examples of the organic solvent used in the dehydration ring-closing reaction include the organic solvents exemplified as those used for the synthesis of polyamic acid. The reaction temperature of the dehydration ring closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C. The reaction time is preferably 1.0 to 120 hours, more preferably 2.0 to 30 hours.

  In this way, a reaction solution containing polyimide (P) is obtained. This reaction solution may be used for the preparation of the liquid crystal aligning agent as it is, may be used for the preparation of the liquid crystal aligning agent after removing the dehydrating agent and the dehydrating ring-closing catalyst from the reaction solution, and the liquid crystal after isolating the polyimide. You may use for preparation of an aligning agent, or you may use for preparation of a liquid crystal aligning agent, after purifying the isolated polyimide. These purification operations can be performed according to known methods.

<Solution viscosity and weight average molecular weight of polymer>
The polyamic acid, polyamic acid ester and polyimide as the polymer (P) obtained as described above have a solution viscosity of 10 to 800 mPa · s when this is a 10% by weight solution. It is preferable to have a solution viscosity of 15 to 500 mPa · s. In addition, the solution viscosity (mPa · s) of the above polymer is based on a polymer solution having a concentration of 10% by weight prepared using a good solvent for the polymer (eg, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). The value measured at 25 ° C. using an E-type rotational viscometer. Moreover, about the polyamic acid, polyamic acid ester, and polyimide which are contained in the liquid crystal aligning agent of this invention, the weight average molecular weight (Mw) of polystyrene conversion measured by the gel permeation chromatography (GPC) is 500-100,000. It is preferable that it is 1,000 to 50,000.

  The proportion of the polymer (P) used is preferably 50 to 100 parts by weight with respect to 100 parts by weight as a whole of the polymer components in the liquid crystal aligning agent. If it is less than 50 parts by weight, the effects of the present invention may not be sufficiently obtained. More preferably, it is 60 weight part or more, More preferably, it is 70 weight part or more. A polymer (P) can be used individually by 1 type or in combination of 2 or more types. The ratio of the polymer (P) used relative to 100 parts by weight of the total amount of solids contained in the liquid crystal aligning agent is preferably 30 parts by weight or more, more preferably 40 parts by weight or more, and 50 parts by weight. More preferably, the above is used.

<Other ingredients>
The liquid crystal aligning agent of this invention may contain the other component as needed. Examples of such other components include other polymers other than the polymer (P), compounds having at least one epoxy group in the molecule (hereinafter referred to as “epoxy group-containing compound”), and functional silane compounds. , Metal chelate compounds, curing accelerators, surfactants and the like.

[Other polymers]
The above other polymers can be used for improving solution properties and electrical properties. Examples of such other polymers include polyamic acid obtained by reaction of a diamine not containing the compound represented by the above formula (1) and tetracarboxylic dianhydride, polyimide obtained by dehydration ring closure of the polyamic acid, Examples thereof include polyamic acid esters, polyorganosiloxanes, polyesters, polyamides, cellulose derivatives, polyacetals, polystyrene derivatives, poly (styrene-phenylmaleimide) derivatives, and poly (meth) acrylates that are esterified products of the polyamic acid.

Moreover, when using the liquid crystal aligning agent of this invention for retardation films, the polymer which has a photo-alignment structure can be used preferably as said other polymer. Here, the photo-alignment structure is a concept including both a photo-alignment group and a decomposition type photo-alignment part. Specific examples include structures that exhibit photo-orientation properties by photoisomerization, photodimerization, photolysis, etc., for example, containing azobenzene, cinnamic acid, chalcone, benzophenone, coumarin and imide ring structures and their derivatives as basic skeletons And the like. Among these, it is preferable to include a polymer having a photoalignment group, and it is more preferable to include a polymer into which a group having a cinnamic acid structure (cinnamic acid or a derivative thereof) is introduced. Among them, a polyorganosiloxane having a cinnamic acid structure can be preferably used because it is easy to introduce a photoalignable group into the polymer.
In addition, the polymer which has a photoalignment group is compoundable by a conventionally well-known method. For example, the polyorganosiloxane having a photoalignable group as another polymer is a polyorganosiloxane having an epoxy group and a carboxylic acid having a photoalignable group, preferably an organic solvent such as ether, ester, ketone, etc. It can synthesize | combine by making it react in presence of catalysts, such as a quaternary ammonium salt.

  When adding another polymer to a liquid crystal aligning agent, it is preferable that the mixture ratio shall be 50 weight part or less with respect to a total of 100 weight part of the polymer contained in a liquid crystal aligning agent, The amount is more preferably 40 parts by weight, and still more preferably 0.1 to 30 parts by weight.

[Epoxy group-containing compound]
The epoxy group-containing compound can be used to improve the adhesion and electrical properties with the substrate surface in the liquid crystal alignment film. Examples of such epoxy group-containing compounds include 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-dibromoneopentyl glycol diglycidyl ether, N, N, N ′, N′-tetraglycidyl-m-xylylene diene Amine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ′, N′-tetraglycidyl-4,4′-diamy Diphenylmethane, N, N-diglycidyl - benzylamine, N, N-diglycidyl - aminomethyl cyclohexane, N, N-diglycidyl - may be mentioned as being preferred and cyclohexylamine. In addition, as an example of the epoxy group-containing compound, an epoxy group-containing polyorganosiloxane described in International Publication No. 2009/096598 can be used.
When adding these epoxy compounds to a liquid crystal aligning agent, it is preferable that the mixture ratio shall be 40 weight part or less with respect to a total of 100 weight part of the polymer contained in a liquid crystal aligning agent, 0.1-30 More preferred are parts by weight.

[Functional silane compounds]
The functional silane compound can be used for the purpose of improving the printability of the liquid crystal aligning agent. Examples of such functional silane compounds include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl). ) -3-Aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3- Aminopropyltrimethoxysilane, N-triethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-trimethoxysilyl -3,6- Methyl azananoate, N-benzyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, glycidoxymethyltrimethoxysilane, 2-glycidoxyethyltrimethoxysilane, 3-glycid And xylpropyltrimethoxysilane.
When these functional silane compounds are added to the liquid crystal aligning agent, the blending ratio is preferably 2 parts by weight or less with respect to a total of 100 parts by weight of the polymer contained in the liquid crystal aligning agent. It is more preferable to set it to -0.2 weight part.

[Metal chelate compounds]
When the polymer component of the liquid crystal aligning agent has an epoxy structure, the metal chelate compound is a liquid crystal aligning agent (particularly a liquid crystal for a retardation film) for the purpose of ensuring the mechanical strength of the film formed by low-temperature treatment. Contained in the alignment agent). As the metal chelate compound, it is preferable to use an acetylacetone complex or acetoacetic acid complex of a metal selected from aluminum, titanium and zirconium. Specifically, for example, diisopropoxyethyl acetoacetate aluminum, tris (acetylacetonate) aluminum, tris (ethylacetoacetate) aluminum, diisopropoxybis (ethylacetoacetate) titanium, diisopropoxybis (acetylacetonate) Examples thereof include titanium, tri-n-butoxyethyl acetoacetate zirconium, and di-n-butoxybis (ethyl acetoacetate) zirconium. When the metal chelate compound is added, the use ratio thereof is preferably 50 parts by weight or less, more preferably 0.1 to 40 parts by weight, with respect to a total of 100 parts of the components including the epoxy structure, More preferably, it is 1-30 weight part.

[Curing accelerator]
When the polymer component in the liquid crystal aligning agent has an epoxy structure, the curing accelerator is a liquid crystal in order to ensure the mechanical strength of the liquid crystal alignment film to be formed and the stability over time of the liquid crystal alignment. It is contained in an aligning agent (particularly a liquid crystal aligning agent for a retardation film). As the curing accelerator, for example, a compound having a phenol group, a silanol group, a thiol group, a phosphoric acid group, a sulfonic acid group, a carboxyl group, a carboxylic anhydride group, or the like can be used. A compound having is preferred. Specific examples thereof include compounds having a phenol group such as cyanophenol, nitrophenol, methoxyphenoxyphenol, thiophenoxyphenol, 4-benzylphenol; compounds having a silanol group such as trimethylsilanol, triethylsilanol, 1 , 1,3,3-tetraphenyl-1,3-disiloxanediol, 1,4-bis (hydroxydimethylsilyl) benzene, triphenylsilanol, tri (p-tolyl) silanol, diphenylsilanediol, etc. be able to. When the curing accelerator is added, the use ratio thereof is preferably 50 parts by weight or less, more preferably 0.1 to 40 parts by weight with respect to 100 parts by weight of the total components including the epoxy structure, and further Preferably it is 1-30 weight part.

[Surfactant]
The surfactant can be contained in a liquid crystal aligning agent (particularly, a liquid crystal aligning agent for a retardation film) for the purpose of improving the applicability of the liquid crystal aligning agent to the substrate. Examples of such surfactants include nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, silicone surfactants, polyalkylene oxide surfactants, and fluorine-containing surfactants. be able to. The proportion of the surfactant used is preferably 10 parts by weight or less, and more preferably 1 part by weight or less with respect to 100 parts by weight of the total amount of the liquid crystal aligning agent.
In addition to the above, other components include compounds having at least one oxetanyl group in the molecule, antioxidants, and the like.

<Solvent>
The liquid crystal aligning agent of the present invention is prepared as a liquid composition in which the polymer (P) and other components used as necessary are preferably dispersed or dissolved in an appropriate solvent.

  Examples of the organic solvent to be used include 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 methoxypropionate, ethyl ethoxypropionate, 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 Recall 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. be able to. These can be used alone or in admixture of two or more.

  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. The range is preferably 1 to 10% by weight. That is, the liquid crystal aligning agent of this invention is apply | coated to a substrate surface so that it may mention later, Preferably the coating film which becomes a liquid crystal aligning film or a coating film used as a liquid crystal aligning film is formed by heating. 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, it is difficult to obtain a good liquid crystal alignment film because the film thickness is excessive, and the viscosity of the liquid crystal aligning agent increases and the applicability decreases. There is a tendency.

  The particularly preferable solid content concentration range varies depending on the use of the liquid crystal aligning agent and the method used when the liquid crystal aligning agent is applied to the substrate. For example, when a liquid crystal aligning agent for a liquid crystal aligning film 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) Is particularly preferably in the range of 1.5 to 4.5% by weight. In the case of the printing method, it is particularly preferable that the solid content concentration is in the range of 3 to 9% by weight, and thereby the solution viscosity is in the range of 12 to 50 mPa · s. In the case of the inkjet method, it is particularly preferable that the solid content concentration is in the range of 1 to 5% by weight, and thereby the solution viscosity is in the range of 3 to 15 mPa · s. The temperature at the time of preparing the liquid crystal aligning agent of this invention becomes like this. Preferably it is 10-50 degreeC, More preferably, it is 20-30 degreeC. Moreover, about the liquid crystal aligning agent for retardation films, the solid content density | concentration of a liquid crystal aligning agent is 0.2 to 10 weight% from a viewpoint which makes the applicability | paintability of a liquid crystal aligning agent, and the film thickness of the coating film formed moderate. It is preferable that it is the range of 3-10 weight%.

<Liquid crystal display element and retardation film>
By using the liquid crystal aligning agent of the present invention described above, a liquid crystal aligning film can be produced. Moreover, the liquid crystal aligning film formed using the liquid crystal aligning agent of this invention is preferably applicable to the liquid crystal aligning film for liquid crystal display elements, and the liquid crystal aligning film for retardation films. Below, the liquid crystal display element and retardation film of this invention are demonstrated.

[Liquid crystal display element]
The liquid crystal display element of this invention comprises the liquid crystal aligning film formed using the said liquid crystal aligning 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. It can be applied to the driving method. The liquid crystal display element of the present invention can be produced, for example, by the following steps (I-1) to (I-3). In step (I-1), the substrate to be used varies depending on the desired operation mode. Steps (I-2) and (I-3) are common to each operation mode.

[Step (I-1): Formation of coating film]
First, the liquid crystal aligning agent of this invention is apply | coated on a board | substrate, Then, a coating film is formed on a board | substrate by heating an application surface.
(I-1A) When manufacturing a TN-type, STN-type, or VA-type liquid crystal display element, for example, first, a pair of two substrates provided with patterned transparent conductive films is formed, and each transparent conductive film is formed. On the surface, the liquid crystal aligning agent of the present invention is preferably applied by an offset printing method, a spin coating method, a roll coater method or an ink jet printing method, respectively. As the substrate, for example, glass such as float glass or soda glass; a transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, poly (cycloaliphatic olefin) can be used. As the 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. Can be used. In order to obtain a patterned transparent conductive film, for example, after forming a transparent conductive film without a pattern, a method of forming a pattern by photo-etching; a method of using a mask having a desired pattern when forming a transparent conductive film; And so on. When applying 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 or a functional titanium compound is formed on the surface of the substrate surface on which the coating film is formed. It is also possible to perform a pretreatment to apply the above in advance.

  After applying the liquid crystal aligning agent, preheating (pre-baking) is preferably performed for the purpose of preventing dripping of the applied liquid crystal aligning agent. The pre-baking 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, and more preferably 0.5 to 5 minutes. Then, a baking (post-baking) process is implemented for the purpose of removing a solvent completely and heat imidating the amic acid structure which exists in a polymer as needed. The firing temperature (post-bake temperature) at this time is preferably 80 to 300 ° C, more preferably 120 to 250 ° C. The post-bake time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The film thickness of the formed film is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

  (I-1B) When manufacturing an IPS type or FFS type liquid crystal display element, an electrode forming surface of a substrate provided with an electrode made of a transparent conductive film or a metal film patterned in a comb shape, and an electrode are provided. The liquid crystal aligning agent of this invention is each apply | coated to one surface of the counter substrate which is not formed, Then, a coating film is formed by heating each application surface. Regarding the material used for the substrate and the transparent conductive film, the coating method, the heating conditions after coating, the patterning method for the transparent conductive film or the metal film, the pretreatment of the substrate, and the preferred film thickness of the coating film to be formed The same as (I-1A). As the metal film, for example, a film made of a metal such as chromium can be used.

  In both cases (I-1A) and (I-1B), after applying a liquid crystal aligning agent on the substrate, an organic solvent is removed to form an alignment film or an alignment film. . At this time, when the polymer contained in the liquid crystal aligning agent of the present invention is a polyamic acid, a polyamic acid ester, or an imidized polymer having an imide ring structure and an amic acid structure Further, after the coating film is formed, the film may be further heated to cause the dehydration ring-closing reaction to proceed so that the coating film is more imidized.

[Step (I-2): Orientation ability imparting treatment]
When manufacturing a TN type, STN type, IPS type, or FFS type liquid crystal display element, as a treatment for imparting liquid crystal alignment ability to the coating film formed in the above step (I-1), the coating film is made of, for example, nylon or rayon. A rubbing process is carried out by rubbing in a certain direction with a roll wound with a cloth made of fibers such as cotton. Thereby, the orientation ability of a liquid crystal molecule is provided to a coating film, and it becomes a liquid crystal aligning film. On the other hand, when producing a VA type liquid crystal display element, the coating film formed in the above step (I-1) can be used as it is as a liquid crystal alignment film, but even if the coating film is rubbed. Good. In addition, the liquid crystal alignment film after the rubbing treatment is further subjected to a treatment for changing the pretilt angle of a part of the liquid crystal alignment film by irradiating a part of the liquid crystal alignment film with ultraviolet light, or a surface of the liquid crystal alignment film. A resist film is formed on the part, and a rubbing process is performed in a direction different from the previous rubbing process, followed by a process of removing the resist film, so that the liquid crystal alignment film has 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. Note that a liquid crystal alignment film suitable for a VA liquid crystal display element can also be suitably used for a PSA (Polymer sustained alignment) liquid crystal display element. As a process for imparting liquid crystal alignment ability to the coating film, a process by a photo-alignment method may be employed instead of the rubbing process.

[Step (I-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 cell is manufactured by disposing a liquid crystal between the two substrates disposed to face each other. In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example. The first method is a conventionally known method. First, two substrates are arranged opposite to each other through a gap (cell gap) so that the respective liquid crystal alignment films are opposed to each other, and the peripheral portions of the two substrates are bonded together using a sealant, and the substrate surface and the sealant are bonded. A liquid crystal cell is manufactured by injecting and filling the liquid crystal into the cell gap partitioned by the step of sealing the injection hole. The second method is a method called an ODF (One Drop Fill) method. For example, an ultraviolet light curable sealant is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and liquid crystal is dropped at predetermined locations on the liquid crystal alignment film surface. After that, the other substrate is bonded so that the liquid crystal alignment films face 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 sealant, thereby manufacturing a liquid crystal cell. . Regardless of which method is used, the liquid crystal cell produced 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. It is desirable to remove.

  As the sealing agent, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as a spacer can be used. Examples of the liquid crystal include nematic liquid crystals and smectic liquid crystals. Among them, nematic liquid crystals are preferable. For example, Schiff base liquid crystals, azoxy liquid crystals, biphenyl liquid crystals, phenyl cyclohexane liquid crystals, ester liquid crystals, terphenyl liquid crystals. Biphenylcyclohexane liquid crystal, pyrimidine liquid crystal, dioxane liquid crystal, bicyclooctane liquid crystal, cubane liquid crystal, and the like can be used. Further, cholesteric liquid crystals such as cholestyl chloride, cholesteryl nonate, cholesteryl carbonate; chiral agents such as those sold under the trade names “C-15” and “CB-15” (manufactured by Merck) A ferroelectric liquid crystal such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate may be added and used.

  And the liquid crystal display element of this invention can be obtained by bonding a polarizing plate on the outer surface of a liquid crystal cell. As a polarizing plate to be bonded to the outer surface of the liquid crystal cell, a polarizing film or an H film itself in which a polarizing film called an “H film” in which iodine is absorbed while stretching and aligning polyvinyl alcohol is sandwiched between cellulose acetate protective films The polarizing plate which consists of can be mentioned.

[Phase difference film]
When producing a retardation film using the liquid crystal aligning agent of the present invention, it is possible to form a uniform liquid crystal aligning film while suppressing the generation of dust and static electricity during the process, suitable for irradiation with radiation. It is preferable to use a photo-alignment method in that a plurality of regions having different liquid crystal alignment directions can be arbitrarily formed on the substrate by using a simple photomask. Specifically, the manufacturing method including the following steps (II-1) to (II-3) can be mentioned.

[Step (II-1): Formation of coating film by liquid crystal aligning agent]
First, the liquid crystal aligning agent of this invention is apply | coated on a board | substrate, and a coating film is formed. As the substrate used here, a transparent substrate made of a synthetic resin such as triacetyl cellulose (TAC), polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polyamide, polyimide, polymethyl methacrylate, polycarbonate, etc. is preferably exemplified. Can do. Of these, TAC is generally used as a protective layer for a polarizing film in a liquid crystal display device. In addition, polymethyl methacrylate can be preferably used as a substrate for a retardation film in that the hygroscopicity of the solvent is low, the optical properties are good, and the cost is low. In addition, for the substrate used for the application of the liquid crystal aligning agent, in order to further improve the adhesion between the substrate surface and the coating film, a conventionally known pretreatment is performed on the surface of the substrate surface on which the coating film is formed. It may be given.

  In many cases, the retardation film is used in combination with a polarizing film. At this time, it is necessary to attach the retardation film by precisely controlling the angle with respect to the polarization axis of the polarizing film in a specific direction so that the desired optical characteristics can be exhibited. Accordingly, by forming a liquid crystal alignment film having a liquid crystal alignment ability in a predetermined angle direction on a substrate such as a TAC film or polymethyl methacrylate, the angle of the retardation film is controlled on the polarizing film. The step of bonding can be omitted. Thereby, it can contribute to the improvement of productivity of a liquid crystal display element. In order to form a liquid crystal alignment film having a liquid crystal alignment ability in a direction of a predetermined angle, it is preferable to carry out by a photo alignment method using the liquid crystal aligning agent of the present invention.

The liquid crystal aligning agent can be applied onto the substrate by an appropriate application method such as a roll coater method, a spinner method, a printing method, an ink jet method, a bar coater method, an extrusion die method, a direct gravure coater method, a chamber. Doctor coater method, offset gravure coater method, single roll kiss coater method, reverse kiss coater method using small diameter gravure roll, 3 reverse roll coater method, 4 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, and the like can be employed.
After coating, the coated surface is heated (baked) to form a coating film. The heating temperature at this time is preferably 40 to 150 ° C, 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 (II-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. Here, examples of the light to be irradiated include ultraviolet rays and visible rays including light having a wavelength of 150 to 800 nm. Among these, ultraviolet rays containing light having a wavelength of 300 to 400 nm are preferable. Irradiation light may be polarized or non-polarized. As the polarized light, it is preferable to use light including linearly polarized light.
When the light to be used is polarized light, the light irradiation may be performed from a direction perpendicular to the substrate surface, an oblique direction, or a combination thereof. When irradiating non-polarized light, it is necessary to carry out from a direction oblique to the substrate surface.
Examples of the light source used include a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, and a mercury-xenon lamp (Hg-Xe lamp). Polarized light can be obtained by means of using these light sources in combination with, for example, a filter or a diffraction grating.
The dose of light is preferably less than 0.1 mJ / cm ² or more 1,000 mJ / cm ^2, more preferably to 1 to 500 mJ / cm ^2, further be 2~200mJ / cm ² preferable.

[Step (II-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, the coating film (liquid crystal layer) containing a polymerizable liquid crystal is formed. The polymerizable liquid crystal used here is a liquid crystal compound or a liquid crystal composition that is polymerized by at least one treatment of heating and light irradiation. As such 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, Vol. 3, No. 1 (1999) ), Pp 34-42). Further, cholesteric liquid crystal; discotic liquid crystal; twisted nematic alignment type liquid crystal to which a chiral agent is added may be used. The polymerizable liquid crystal may be a mixture of a plurality of liquid crystal compounds. The polymerizable liquid crystal may be a composition further containing a known polymerization initiator or a suitable solvent.
In order to apply the polymerizable liquid crystal as described above onto a coating film formed using a liquid crystal aligning agent, for example, an appropriate application method such as a bar coater method, a roll coater method, a spinner method, a printing method, an ink jet method or the like is used. Can be adopted.

Next, the coating film of the polymerizable liquid crystal formed as described above is subjected to one or more treatments selected from heating and light irradiation to cure the coating film to form a liquid crystal layer. It is preferable to perform these treatments in a superimposed manner because good alignment can be obtained.
The heating temperature of the coating film should be appropriately selected depending on the type of polymerizable liquid crystal 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 irradiation light, non-polarized ultraviolet rays 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 depending on desired optical characteristics. For example, when manufacturing a half-wave plate for visible light having a wavelength of 540 nm, a 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 from which the desired retardation is obtained varies depending on the optical characteristics of the polymerizable liquid crystal used. For example, when RMS03-013C manufactured by Merck is used, the thickness for manufacturing 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 as a retardation film of a liquid crystal display element. The liquid crystal display element to which the retardation film manufactured using the liquid crystal aligning agent of the present invention is applied is not limited in its driving method. For example, TN type, STN type, IPS type, FFS type, VA type and the like are known. It can be applied to various methods. The retardation film is used by attaching the substrate-side surface of the retardation film to the outer surface of the polarizing plate disposed on the viewing side of the liquid crystal display element. Therefore, it is preferable that the retardation film substrate is made of TAC or an acrylic base, and the retardation film substrate also functions as a protective film for the polarizing film.

  The liquid crystal display element of the present invention can be effectively applied to various devices, such as watches, portable games, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, cellular phones, smartphones, various types. It can be used for various display devices such as a monitor, a liquid crystal television, and an information display.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

In the following Examples and Synthesis Examples, the polymer weight average molecular weight Mw, imidization rate and epoxy equivalent, and the solution viscosity of the polymer solution were measured by the following methods.
[Weight average molecular weight Mw of polymer]
Mw is a polystyrene equivalent value measured by gel permeation chromatography under the following conditions.
Column: Tosoh Co., Ltd., TSKgelGRCXLII
Solvent: Tetrahydrofuran Temperature: 40 ° C
Pressure: 68 kgf / cm ²
[Imidation rate of polymer]
A solution containing polyimide is poured into pure water, and the resulting precipitate is sufficiently dried at room temperature under reduced pressure, then dissolved in deuterated dimethyl sulfoxide, and ¹ H-NMR is measured at room temperature using tetramethylsilane as a reference substance. did. From the obtained ¹ H-NMR spectrum, the imidation ratio was determined using the following mathematical formula (1).
Imidation ratio (%) = (1-A ¹ / A ² × α) × 100 (1)
(In Formula (1), A ¹ is a peak area derived from protons of NH groups appearing near 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). The number ratio of other protons to one proton of NH group in)
[Epoxy equivalent]
The epoxy equivalent was measured by the hydrochloric acid-methyl ethyl ketone method described in JIS C 2105.
[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.

<Synthesis of diamine>
[Example 1-1; Synthesis of Compound (DA-1)]
According to the following scheme 1, a compound represented by the above formula (DA-1) (hereinafter referred to as compound (DA-1)) was synthesized.

In a 3 L three-necked flask equipped with a thermometer and a three-way cock, 105.1 g (0.53 mol) of 4- (benzyloxy) phenol, 57.5 g (0.25 mol) of 1,5-dibromopentane, 138. potassium carbonate. 2 g (1.0 mol) and 1250 ml of dimethylformamide (DMF) were added and mixed. Subsequently, after heating up to 60 degreeC and making it react for 6 hours, it mixed with 2000 ml of ethyl acetate, and liquid-separated and washed with distilled water after that. Next, the organic layer was concentrated to precipitate a solid. The obtained solid was recrystallized from ethyl acetate and hexane, collected by filtration, and dried to give a compound represented by the above formula (DA-1-1) (shown as Compound (DA-1-1)). 99.6 g (0.21 mol) was obtained.
Next, 99.6 g (0.21 mol) of the compound (DA-1-1) obtained above and 10 g of 5% Pd / C were weighed into a 2 L three-necked flask equipped with a thermometer, a three-way cock and a dropping funnel. The system was evacuated and purged with nitrogen. Next, 1000 ml of tetrahydrofuran (THF) was added, and 100 ml of hydrazine monohydrate was slowly added dropwise while cooling so as not to exceed 10 ° C. Subsequently, it was made to react at room temperature for 6 hours. The solvent used for the reaction was previously substituted with nitrogen. After the reaction, the inorganic salt was removed by filtration, 1000 ml of ethyl acetate was mixed with the filtrate, and then separated and washed with distilled water. Next, the organic layer was concentrated to precipitate a solid. The obtained solid was collected and dried to obtain 56.4 g (0.20 mol) of a compound represented by the above formula (DA-1-2) (shown as compound (DA-1-2)). Obtained.

Next, in a 1 L three-necked flask equipped with a thermometer and a three-way cock, 56.4 g (0.20 mol) of the compound (DA-1-2) obtained above and 56.5 g of 4-fluoronitrobenzene (0. 40 mol), 108.1 g (0.78 mol) of potassium carbonate and 500 ml of dimethylformamide (DMF) were added and mixed. Subsequently, after heating up to 60 degreeC and making it react for 6 hours, it mixed with 1000 ml of ethyl acetate, and liquid-separated and washed with distilled water after that. Next, the organic layer was concentrated to precipitate a solid. The obtained solid was recrystallized from ethyl acetate and hexane, collected by filtration, and dried to show the compound represented by the above formula (DA-1-3) (dinitro intermediate (DA-1-3)). ) Was obtained 74.7 g (0.14 mol).
Next, in a 2 L autoclave under a nitrogen stream, 74.7 g (0.14 mol) of the above dinitro intermediate (DA-1-3), 7.5 g of 5% Pd / C, 200 mL of ethanol and 800 mL of tetrahydrofuran were added. After the addition, replacement with hydrogen was performed again, and the reaction was performed at room temperature in the presence of hydrogen. The reaction was followed by liquid chromatography, and after confirming the progress of the reaction, the reaction was filtered. The filtrate and 3000 mL of ethyl acetate were mixed and then separated and purified with distilled water. A solid was precipitated by removing the solvent from the obtained organic layer by distillation under reduced pressure. The precipitated solid was recrystallized from ethanol to obtain 58.3 g (0.12 mol) of Compound (DA-1).

[Example 1-2; Synthesis of compound (DA-2)]
According to the following scheme 2, a compound represented by the above formula (DA-2) (hereinafter referred to as compound (DA-2)) was synthesized.

In a 3 L three-necked flask equipped with a thermometer and a three-way cock, 99.5 g (0.5 mol) of 3-phenylpropyl bromide, 51.8 g (0.55 mol) of phenol, and 207.3 g (1.5 mol) of potassium carbonate And 2000 ml of dimethylformamide (DMF) were added and mixed. Subsequently, after heating up to 60 degreeC and making it react for 6 hours, it mixed with 2000 ml of ethyl acetate, and liquid-separated and washed with distilled water after that. Next, the organic layer was concentrated to precipitate a solid. The obtained solid was recrystallized from ethanol, collected by filtration, and dried to give a compound represented by the above formula (DA-2-1) (shown as Compound (DA-2-1)) at 77. 5 g (0.37 mol) was obtained.
Next, 243.3 g (1.83 mol) of aluminum chloride and 1000 mL of methylene chloride were mixed in a 2 L three-necked flask equipped with a thermometer and a three-way cock, and 162.6 g of 4-nitrobenzoic acid chloride (under ice cooling) 0.88 mol) was added and dissolved. Next, 400 mL of a methylene chloride solution containing 77.5 g (0.37 mol) of the compound (DA-2-1) was slowly added dropwise. After completion of dropping, the reaction was allowed to proceed for 6 hours while returning to room temperature. After confirming the completion of the reaction by liquid chromatography, the reaction solution was poured into a mixture of 10N hydrochloric acid and ice, and then extracted with chloroform. Subsequently, it wash | cleaned with sodium hydrogencarbonate aqueous solution, salt solution, and distilled water, and the organic layer was dried with magnesium sulfate. Subsequently, the solvent was removed by distillation under reduced pressure, and filtration was performed when crystals were sufficiently precipitated. 95.0 g of the compound represented by the above formula (DA-2-2) (shown as compound (DA-2-2)) was washed successively with water, ethanol and toluene and dried under reduced pressure. (0.19 mol) was obtained.

Next, 95.0 g of compound (DA-2-2) and 500 mL of dichloromethane were placed in a 1 L three-necked flask equipped with a thermometer, a dropping funnel and a three-way cock, and 120 g of trifluoromethanesulfonic acid was slowly added dropwise under ice cooling. . Subsequently, 120 g of triethylsilane was slowly added dropwise. After completion of dropping, the reaction was allowed to proceed for 10 hours while returning to room temperature. After confirming the completion of the reaction by liquid chromatography, the reaction solution was neutralized with an aqueous sodium carbonate solution and washed with water. The organic layer is concentrated, and a solid is precipitated, and then recrystallized with a toluene solvent, whereby the compound represented by the above formula (DA-2-3) (shown as dinitro intermediate (DA-2-3)). Of 71.9 g (0.15 mol) was obtained.
Next, 71.9 g (0.15 mol) of the dinitro intermediate (DA-2-3), 7.2 g of 5% Pd / C, 200 mL of ethanol and 800 mL of tetrahydrofuran were placed in a 2 L autoclave under a nitrogen stream. After the addition, replacement with hydrogen was performed again, and the reaction was performed at room temperature in the presence of hydrogen. The reaction was traced by HPLC, followed by filtration after confirming the progress of the reaction. The filtrate and 3000 mL of ethyl acetate were mixed and then separated and purified with distilled water. A solid was precipitated by removing the solvent from the obtained organic layer by distillation under reduced pressure. The precipitated solid was recrystallized from ethanol to obtain 53.3 g (0.13 mol) of Compound (DA-2).

[Example 1-3; Synthesis of Compound (DA-3)]
According to the following scheme 3, a compound represented by the above formula (DA-3) (hereinafter referred to as compound (DA-3)) was synthesized.

In a 3 L three-necked flask equipped with a thermometer and a three-way cock, 4-hydroxy-4′-nitrobiphenyl 180.8 g (0.84 mol), 1,3-dibromopropane 80.8 g (0.4 mol), potassium carbonate 221.1 g (1.6 mol) and 2000 ml of dimethylformamide (DMF) were added and mixed. Subsequently, after heating up to 60 degreeC and making it react for 6 hours, it mixed with 4000 ml of ethyl acetate, and liquid-separated and washed with distilled water after that. Next, the organic layer was concentrated to precipitate a solid. The obtained solid was recrystallized from ethanol, collected by filtration, and dried to give a compound represented by the above formula (DA-3-1) (shown as dinitro intermediate (DA-3-1)). 103.5 g (0.22 mol) was obtained.
Next, 103.5 g (0.22 mol) of the above dinitro intermediate (DA-3-1), 10.3 g of 5% Pd / C, 100 mL of ethanol and 500 mL of tetrahydrofuran were placed in a 2 L autoclave under a nitrogen stream. After the addition, replacement with hydrogen was performed again, and the reaction was performed at room temperature in the presence of hydrogen. The reaction was traced by HPLC, followed by filtration after confirming the progress of the reaction. The filtrate and 1000 mL of ethyl acetate were mixed, and then separated and purified with distilled water. A solid was precipitated by removing the solvent from the obtained organic layer by distillation under reduced pressure. The precipitated solid was recrystallized from ethanol to obtain 151.7 g (0.37 mol) of Compound (DA-3).

[Example 1-4; Synthesis of Compound (DA-4)]
According to the following scheme 4, a compound represented by the above formula (DA-4) (hereinafter referred to as compound (DA-4)) was synthesized.

In a 1 L three-necked flask equipped with a thermometer, a three-way cock and a dropping funnel, 43.4 g (0.15 mol) of a compound (DA-1-2) obtained in the same manner as in Example 1-1, triethylamine ( (TEA) 60.7 g (0.6 mol) and 300 ml of THF were mixed, and a solution of 69.6 g (0.38 mol) of 4-nitrobenzoyl chloride in 400 ml of THF was slowly added dropwise under ice cooling. After dropping, the mixture was reacted at room temperature for 12 hours, mixed with 1000 ml of ethyl acetate, and then separated and washed with distilled water. Next, the organic layer was concentrated to precipitate a solid. The obtained solid was recrystallized from ethyl acetate and hexane, collected by filtration, and dried to show the compound represented by the above formula (DA-4-1) (dinitro intermediate (DA-4-1)). 39.6 g (0.07 mol) was obtained.
Next, after adding 39.6 g (0.07 mol) of the above dinitro intermediate (DA-4-1), 4 g of 5% Pd / C, 100 mL of ethanol and 250 mL of tetrahydrofuran to a 2 L autoclave under a nitrogen stream. Then, replacement with hydrogen was performed again, and the reaction was performed at room temperature in the presence of hydrogen. The reaction was traced by HPLC, followed by filtration after confirming the progress of the reaction. A solid was precipitated by removing the solvent from the organic layer by vacuum distillation. The precipitated solid was recrystallized from ethanol to obtain 27.4 g (0.05 mol) of Compound (DA-4).

According to the following scheme 5, a compound represented by the following formula (DA-16) (hereinafter referred to as compound (DA-16)) was synthesized.

In a 1 L three-necked flask equipped with a thermometer, a three-way cock and a dropping funnel, 43.0 g (0.15 mol) of 1,5-bis (4-aminophenoxy) pentane, 60.7 g (0.6 mol) of triethylamine, and 300 ml of THF was mixed, and a solution of 69.6 g (0.38 mol) of 4-nitrobenzoic acid chloride in 400 ml of THF was slowly added dropwise under ice cooling. After dropping, the mixture was reacted at room temperature for 12 hours, mixed with 1000 ml of ethyl acetate, and then separated and washed with distilled water. Next, the organic layer was concentrated to precipitate a solid. The obtained solid was recrystallized from ethyl acetate and hexane, collected by filtration, and dried to obtain 46.8 g (0.08 mol) of an intermediate (DA-16-1).
Next, 46.8 g (0.08 mol) of the above nitro intermediate (DA-16-1), 4.5 g of 5% Pd / C, 100 mL of ethanol and 250 mL of tetrahydrofuran were added to a 2 L autoclave under a nitrogen stream. After replacement with hydrogen, the reaction was carried out at room temperature in the presence of hydrogen. The reaction was traced by HPLC, followed by filtration after confirming the progress of the reaction. A solid was precipitated by removing the solvent from the organic layer by distillation under reduced pressure. The precipitated solid was recrystallized from ethanol to obtain 31.5 g (0.06 mol) of the target compound (DA-16) as a white solid.

<Synthesis of polymer>
[Example 2-1; Synthesis of polymer (PA-1)]
10.7 g of pyromellitic dianhydride as tetracarboxylic dianhydride (93 mol parts with respect to 100 mol parts of the total amount of diamine used in the synthesis) and 12.41 g of compound (DA-1) as diamine ( 50 mol parts), 4.82 g (40 mol parts) of 4-aminophenyl-4′-aminobenzoate and 4,4 ′-[4,4′-propane-1,3-diylbis (piperidine-1,4). -Diyl)] 2.07 g (10 mole parts) of dianiline was dissolved in a mixed solvent of 85 g of N-methyl-2-pyrrolidone (NMP) and 85 g of γ-butyllactone (GBL) and reacted at 30 ° C. for 6 hours. went. The reaction mixture was then poured into a large excess of methanol to precipitate the reaction product. The recovered precipitate was washed with methanol and then dried under reduced pressure at 40 ° C. for 15 hours to obtain 28.2 g of polyamic acid (hereinafter referred to as polymer (PA-1)). The obtained polymer (PA-1) was prepared so that it might become 15 weight% in the solvent composition of NMP: GBL = 50: 50, and when the viscosity of this solution was measured, it was 550 mPa * s. Further, when this polymer solution was allowed to stand at 20 ° C. for 3 days, it did not gel and the storage stability was good.

[Example 2-2 to Example 2-5, Example 2-7, Example 2-8, Synthesis Examples 1 and 2]
In Example 2-1 above, a polymer was obtained in the same manner as in Example 2-1, except that the types and amounts of tetracarboxylic dianhydride and diamine used in the reaction were changed as shown in Table 1 below. In addition, the numerical value of Table 1 shows the use ratio (mol%) with respect to the whole quantity of the tetracarboxylic dianhydride used for reaction about the tetracarboxylic dianhydride, About the diamine, the diamine used for reaction The ratio of use (mol%) to the total amount of is shown. Each of the polymer solutions obtained in the examples was allowed to stand at 20 ° C. for 3 days. None of them was gelled, and the storage stability was good.

Abbreviations of tetracarboxylic dianhydride and diamine in Table 1 are as follows.
(Tetracarboxylic dianhydride)
AN-1; 1,2,3,4-cyclobutanetetracarboxylic dianhydride AN-2; pyromellitic dianhydride AN-3; 2,3,5-tricarboxycyclopentylacetic dianhydride AN-4; Ethylenediaminetetraacetic dianhydride AN-5; 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2- c] Furan-1,3-dione (diamine)
da-1; compound da-2 represented by the following formula (da-1); 4-aminophenyl-4′-aminobenzoate da-3; 4,4′-diaminodiphenylmethane da-4; 4,4′- [4,4′-propane-1,3-diylbis (piperidine-1,4-diyl)] dianiline da-5; 2,4-diamino-N, N-diallylaniline da-6; 4,4′-diamino Diphenylamine da-7; 3,5-diaminobenzoic acid da-8; 3,5-diaminobenzoic acid cholestanyl da-9; 4- (tetradecaoxy) benzene-1,3-diamine da-10: the above formula (DA -15) Compound da-11: 1,4-bis- (5-amino-pyridin-2-yl) -piperazine DA-16: Compound represented by the above formula (DA-16)

[Example 2-6; Synthesis of polymer (PI-1)]
16.58 g of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride (98 mol parts with respect to 100 mol parts of the total amount of diamine used in the synthesis), and compound (DA- 2) 25.52 g (80 mol parts) and 7.89 g (20 mol parts) of cholestanyl 3,5-diaminobenzoate were dissolved in 200 g of NMP and reacted at room temperature for 6 hours. Next, 250 g of NMP was added, 11.7 g of pyridine and 15.11 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 80 ° C. for 5 hours. The reaction mixture was then poured into a large excess of methanol to precipitate the reaction product. The recovered precipitate was washed with methanol, and then dried at 40 ° C. under reduced pressure for 15 hours to obtain a polyimide having an imidation ratio of about 65% (hereinafter referred to as polymer (PI-1)). The obtained polymer (PI-1) was prepared to be 15% by weight with NMP. It was 890 mPa * s when the viscosity of this solution was measured.

[Synthesis Example 3; Synthesis of polyorganosiloxane]
A reaction vessel equipped with a stirrer, thermometer, dropping funnel and reflux condenser was charged with 100.0 g of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 500 g of methyl isobutyl ketone and 10.0 g of triethylamine, and room temperature. Mixed. 100 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and the reaction was carried out at 80 ° C. for 6 hours while mixing under reflux. After completion of the reaction, the organic layer is taken out, washed with 0.2 wt% ammonium nitrate aqueous solution until the water after washing becomes neutral, and then the solvent and water are distilled off under reduced pressure to have an oxiranyl group. Polyorganosiloxane was obtained as a viscous transparent liquid. When ¹ H-NMR analysis was performed on the polyorganosiloxane having an oxiranyl group, a peak based on the oxiranyl group was obtained in the vicinity of the chemical shift (δ) = 3.2 ppm according to the theoretical intensity. It was confirmed that no side reaction occurred. The epoxy equivalent of the polyorganosiloxane having an oxiranyl group was measured and found to be 186 g / equivalent.
Next, in a 100 mL three-necked flask, 9.3 g of the polyorganosiloxane having the oxiranyl group obtained above, 26 g of methyl isobutyl ketone, 3 g of 4-phenoxycinnamic acid and UCAT 18X (trade name, manufactured by San Apro Co., Ltd.) 0.10 g Was reacted at 80 ° C. for 12 hours with stirring. After completion of the reaction, the reaction mixture was poured into methanol to recover the generated precipitate, which was dissolved in ethyl acetate to form a solution. 6.3 g of polyorganosiloxane (S-1) having a cinnamic acid structure was obtained as a white powder. The weight average molecular weight Mw in terms of polystyrene measured by gel permeation chromatography for this polyorganosiloxane (S-1) was 3,500.

<Preparation and evaluation of liquid crystal aligning agent>
[Example 3-1: FFS type liquid crystal display element]
(1) Preparation of liquid crystal aligning agent As a polymer, 100 parts by weight of the polymer (PA-1) obtained in Example 2-1 was mixed with γ-butyrolactone (GBL), NMP and butyl cellosolve (BC) (GBL). : NMP: BC = 40: 40: 20 (weight ratio)) to obtain a solution having a solid content concentration of 3.5% by weight. A liquid crystal aligning agent was prepared by filtering this solution through a filter having a pore size of 0.2 μm.

(2) Evaluation of applicability The liquid crystal aligning agent prepared above was applied on a glass substrate using a spinner, pre-baked on an 80 ° C. hot plate for 1 minute, and then the interior of the chamber was purged with nitrogen. A coating film having an average film thickness of 1,000 mm was formed by heating (post-baking) in an oven for 1 hour. This coating film was observed with a microscope having a magnification of 100 times to examine the presence or absence of film thickness unevenness and pinholes. In the evaluation, the case where neither film thickness unevenness nor pinhole was observed was evaluated as “good”, and the case where at least one of film thickness unevenness and pinhole was observed was determined as “bad”. In this example, neither film thickness unevenness nor pinhole was observed, and the coating property was “good”.

(3) Evaluation of rubbing resistance The coating film obtained above was rubbed at a roll rotation speed of 1000 rpm, a stage moving speed of 20 cm / sec, and a hair foot indentation length of 0.4 mm by a rubbing machine having a roll wrapped with a cotton cloth. The treatment was performed 7 times. Foreign matter (a piece of coating film) due to rubbing scraping on the obtained substrate was observed with an optical microscope, and the number of foreign matters in a 500 μm × 500 μm region was measured. In the evaluation, the rubbing resistance was “good” when the number of foreign substances was 3 or less, “good” when 4 or more and 7 or less were present, and the rubbing resistance “bad” when 8 or more. As a result, the rubbing resistance of this coating film was “good”.

(4) Manufacture of FFS type liquid crystal display element The FFS type liquid crystal display element shown in FIG. 1 was produced. First, a glass substrate 11a having two electrode pairs on one side each having a bottom electrode 15 having no pattern, a silicon nitride film as an insulating layer 14, and a top electrode 13 patterned in a comb shape in this order. And the counter glass substrate 11b provided with no electrode, and the liquid crystal aligning agent prepared in the above (1) is applied to the surface having the transparent electrode of the glass substrate 11a and one surface of the counter glass substrate 11b, respectively. Was applied to form a coating film. Next, this coating film was pre-baked for 1 minute on a hot plate at 80 ° C., and then heated (post-baked) at 230 ° C. for 15 minutes in an oven in which the inside of the chamber was replaced with nitrogen, so that the average film thickness was 1,000 mm. A coating film was formed. A schematic plan view of the top electrode 13 is shown in FIG. 2A is a top view of the top electrode 13, and FIG. 2B is an enlarged view of a portion C1 surrounded by a broken line in FIG. 2A. In this example, the line width d1 of the electrodes was 4 μm, and the distance d2 between the electrodes was 6 μm.

  Next, a rubbing process was performed on each surface of the coating film formed on the glass substrate with cotton to obtain a liquid crystal alignment film 12. In FIG.2 (b), the rubbing direction with respect to the coating film formed on the glass substrate 11a is shown by the arrow. These substrates are bonded through a spacer having a diameter of 3.5 μm so that the rubbing directions of the substrates 11a and 11b are antiparallel, and liquid crystal MLC-6221 (manufactured by Merck) is injected, and the liquid crystal layer 16 is injected. Formed. Furthermore, the liquid crystal display element 10 was produced by bonding a polarizing plate (not shown) on both outer surfaces of the substrates 11a and 11b so that the polarization directions of the two polarizing plates were orthogonal to each other.

(5) Evaluation of liquid crystal orientation For the FFS type liquid crystal display device manufactured as described above, the presence or absence of abnormal domains in the change in brightness when a voltage of 5 V is turned ON / OFF (applied / released) is observed with a microscope at a magnification of 50 times. did. In the evaluation, when the abnormal domain was not observed, the liquid crystal alignment was “good”, and when the abnormal domain was observed, the liquid crystal alignment was “bad”. In this liquid crystal display element, the liquid crystal orientation was “good”.
(6) Evaluation of voltage holding ratio For the FFS type liquid crystal display device manufactured as described above, a voltage of 5 V was applied at 23 ° C. with an application time of 60 microseconds and a span of 167 milliseconds, and 167 milliseconds after the release of application. When the voltage holding ratio (VHR) of was measured, it was 99.2%. In addition, as a measuring apparatus, Toyo Technica Co., Ltd. make and VHR-1 were used.

(7) per FFS type liquid crystal display device manufactured in heat-resistant evaluation above, to measure the voltage holding ratio similarly to the above (6), and its value as an initial VHR _{(VHR BF).} Next, the liquid crystal display element after the initial VHR measurement was left in an oven at 100 ° C. for 300 hours. Thereafter, the liquid crystal display element was left at room temperature and allowed to cool to room temperature, and then the voltage holding ratio (VHR _AF ) was measured in the same manner as described above. Moreover, the change rate (ΔVHR (%)) of the voltage holding ratio before and after the application of thermal stress was determined by the following mathematical formula (2).
ΔVHR = ((VHR _BF −VHR _AF ) ÷ VHR _BF ) × 100 (2)
Evaluation of heat resistance is “good” when the rate of change ΔVHR is less than 4%, “good” when 4% or more and less than 5%, and “high” when 5% or more. Went as "bad". As a result, ΔVHR of the liquid crystal display element of this example was 1.9%, and the heat resistance was “good”.

(8) Pretilt angle characteristics With respect to the liquid crystal display element manufactured above, the tilt angle of the liquid crystal molecules from the substrate surface was measured by a crystal rotation method using He-Ne laser light, and this value was defined as a pretilt angle θ. Non-Patent Document 1 (TJScheffer et.al., J. Appl. Phys. Vol. 48, p1783 (1977)) and Non-Patent Document 2 (F. Nakano et.al., JPN. J. Appl). Phys. Vol. 19, p2013 (1980)).
In the evaluation, when the pretilt angle θ is less than 1.0 °, the pretilt angle evaluation is “good”, and when it is 1.0 ° or more, the pretilt angle evaluation is “bad”. The pretilt angle change rate was 0.3 °, and the pretilt angle stability was judged as “good”.
(9) Contrast evaluation after driving stress (AC afterimage characteristics evaluation)
An FFS type liquid crystal cell was produced by performing the same operation as in the above (4) except that the polarizing plate was not bonded to both outer surfaces of the substrate. For this FFS type liquid crystal cell, a minimum relative transmission represented by the following formula (3) is used by using a device in which a polarizer and an analyzer are arranged between a light source and a light amount detector after being driven at an AC voltage of 10 V for 30 hours. The rate (%) was measured.
Minimum relative transmittance (%) = (β−B ⁰ ) / (B ¹⁰⁰ −B ⁰ ) × 100 (3)
(In Formula (3), B ⁰ is the transmission amount of light under a crossed Nicol in a blank. B ¹⁰⁰ is the transmission amount of light under a Paranicol in a blank. Β is a polarizer under a crossed Nicol. (This is the minimum light transmission amount with the liquid crystal display element sandwiched between the analyzers.)
The black level in the dark state is expressed by the minimum relative transmittance of the liquid crystal display element. In the FFS type liquid crystal display element, the smaller the black level in the dark state, the better the contrast. A sample having a minimum relative transmittance of less than 0.5% was evaluated as “good”, a sample having a minimum relative transmittance of less than 0.5% and less than 1.0% was evaluated as “good”, and a sample having a minimum relative transmittance of 1.0% or more was determined as “bad”. As a result, the minimum relative transmittance of this liquid crystal cell was 0.2%, which was judged as “good”.

[Example 3-2 to Example 3-5, Example 3-9 and Comparative Examples 1 and 2]
In Example 3-1 above, a liquid crystal aligning agent was prepared in the same manner as in Example 3-1, except that the polymer shown in Table 2 was used, and an FFS type liquid crystal display device was produced. Various evaluations were performed. The evaluation results are shown in Table 2 below.

  As shown in Table 2, in Examples 3-1 to 3-5 and 3-9, good results were obtained with respect to the coating property of the liquid crystal aligning agent and the rubbing resistance of the coating film. In addition, the orientation of liquid crystal molecules, voltage holding ratio, heat resistance, pretilt angle characteristics, and AC afterimage characteristics in the liquid crystal display element were also good results. On the other hand, in the comparative example 1, the applicability | paintability of the liquid crystal aligning agent was "poor", and it was a result inferior to the Example about the rubbing tolerance of a coating film. Moreover, in the liquid crystal display element of the comparative example 1, the voltage holding ratio, the pretilt angle characteristic, and the AC afterimage specification were inferior to the examples. In Comparative Example 2, a polymer obtained by reacting 1,2,3,4-cyclobutanetetracarboxylic dianhydride and compound (DA-1) was used, but the voltage holding ratio was low, and the liquid crystal cell The heat resistance was “bad”.

[Example 3-6: TN liquid crystal display element]
(1) Preparation of liquid crystal aligning agent 100 parts by weight of the polymer (PA-7) obtained in Example 2-5 as a polymer was used as a mixed solvent of NMP and BC (NMP: BC = 50: 50 (weight ratio)). This was dissolved to obtain a solution having a solid content concentration of 6.5% by weight. After sufficiently stirring this solution, a liquid crystal aligning agent was prepared by filtering through a filter having a pore size of 0.2 μm.
(2) Evaluation of printability The liquid crystal aligning agent prepared in the above (1) is applied to the transparent electrode surface of the glass substrate with a transparent electrode made of an ITO film using a liquid crystal alignment film printer (Nissha Printing Co., Ltd.). Apply and heat for 1 minute on a hot plate at 80 ° C (pre-bake) to remove the solvent, then heat on a hot plate at 200 ° C for 10 minutes (post-bake) to form a coating film with an average film thickness of 600 mm did. This coating 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, when neither printing unevenness nor pinhole was observed, the printability was “good”, and when at least one of printing unevenness and pinhole was slightly observed, printability was “good”, printing unevenness and pin The case where at least one of the holes was frequently observed was regarded as “printing failure”. In this example, neither printing unevenness nor pinholes were observed, and the printability was “good”.

(3) Manufacture of TN type liquid crystal cell Transparent electrode of glass substrate with transparent electrode made of ITO liquid crystal aligning agent prepared in (1) above using liquid crystal alignment film printer (Nissha Printing Co., Ltd.) After coating on the surface and heating (pre-baking) on a hot plate at 80 ° C. for 1 minute to remove the solvent, heating (post-baking) on a hot plate at 200 ° C. for 10 minutes to obtain a coating film with an average film thickness of 600 mm Formed. This coating film was rubbed with a rubbing machine having a roll wrapped with a rayon cloth at a roll rotation speed of 500 rpm, a stage moving speed of 3 cm / sec, and a hair foot indentation length of 0.4 mm to give liquid crystal alignment ability. . Then, ultrasonic cleaning was performed in ultrapure water for 1 minute, and then drying was performed in a 100 ° C. clean oven for 10 minutes to obtain a substrate having a liquid crystal alignment film. The above operation was repeated to obtain a pair (two) of substrates having a liquid crystal alignment film.
Next, for one of the pair of substrates, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 μm is applied to the outer edge of the surface having the liquid crystal alignment film, and then the pair of substrates is aligned with the liquid crystal alignment film surface. The adhesives were cured by overlapping and pressing them so that they face each other. Next, a nematic liquid crystal (MLC-6221, manufactured by Merck & Co., Inc.) is filled between a pair of substrates from the liquid crystal injection port, and then the liquid crystal injection port is sealed with an acrylic photo-curing adhesive, whereby a TN liquid crystal cell is obtained. Manufactured.

(4) Evaluation of liquid crystal orientation About the TN type | mold liquid crystal cell manufactured by said (3), the presence or absence of the abnormal domain when the voltage of 5V was turned on / off under crossed Nicols was observed with the microscope at 50 time magnification. Evaluation was performed in the same manner as in Example 3-1 (5). As a result, in this liquid crystal cell, the liquid crystal alignment was “good”.

(5) Evaluation of pretilt angle stability For the TN liquid crystal cell manufactured in (3) above, the angle of inclination of the liquid crystal molecules from the substrate surface is measured by a crystal rotation method using He—Ne laser light, and this value is expressed as It was the initial pre-tilt angle θ _IN. Non-Patent Document 1 (TJScheffer et.al., J. Appl. Phys. Vol. 48, p1783 (1977)) and Non-Patent Document 2 (F. Nakano et.al., JPN. J. Appl). Phys. Vol. 19, p2013 (1980)).
Then, the liquid crystal cell was measured for initial pretilt angle theta _IN, and the alternating voltage of 5V was applied for 100 hours. Thereafter, the pretilt angle was measured again by the same method as described above, and this value was defined as the pretilt angle θ _AF after voltage application. By substituting these measured values into the following formula (4), the amount of change in the pretilt angle (Δθ (°)) before and after voltage application was determined.
Δθ = | θ _AF −θ _IN | (4)
Pretilt angle stability is “good” when Δθ is less than 3%, pretilt angle stability is “good” when it is 3% or more and less than 4%, and pretilt angle stability is when it is 4% or more. As a result of evaluating “Poor”, the pretilt angle change rate of this liquid crystal cell was 2.8%, and it was judged that the pretilt angle stability was “good”.

(6) Evaluation of voltage holding ratio and heat resistance The voltage holding ratio (VHR _BF ) was measured in the same manner as (6) in Example 3-1 and the same as (7) in Example 3-1 above. Thus, the heat resistance of the liquid crystal display element was evaluated based on the change rate of the voltage holding ratio before and after application of thermal stress. As a result, VHR _BF was 98.9%. Further, ΔVHR was 2.9%, and the heat resistance was judged as “good”.

[Example 3-7: VA liquid crystal display element]
(1) Preparation of liquid crystal aligning agent NMP and BC were added to 100 parts by weight of the polymer (PI-1) obtained in Example 2-6 as a polymer, and the solid content concentration was 6.5% by weight. Was a solution of NMP: BC = 50: 50 (weight ratio). After sufficiently stirring this solution, a liquid crystal aligning agent was prepared by filtering with a filter having a pore size of 0.2 μm.
(2) Evaluation of printability Using the liquid crystal aligning agent prepared in (1) above, the printability was examined in the same manner as in Example 2-5 (2). It was not observed and the printability was “good”.

(3) Manufacture of VA type liquid crystal cell The liquid crystal aligning agent prepared above is liquid crystal aligning film printer (Nissha Printing Co., Ltd.) on the transparent electrode surface of a glass substrate with a transparent electrode (thickness 1 mm) made of ITO film. )), And heated (pre-baked) for 1 minute on a hot plate at 80 ° C. and further heated (post-baked) for 60 minutes on a hot plate at 200 ° C. Liquid crystal alignment film) was formed. This operation was repeated to obtain a pair (two) of glass substrates having a liquid crystal alignment film on the transparent conductive film. Next, for one of the pair of substrates, an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 μm is applied to the outer edge of the surface having the liquid crystal alignment film, and then the pair of substrates is aligned with the liquid crystal alignment film surface. The adhesives were cured by overlapping and pressing so that they face each other. Next, a nematic liquid crystal (MLC-6608, manufactured by Merck & Co., Inc.) was filled between the pair of substrates through the liquid crystal injection port, and then the liquid crystal injection port was sealed with an acrylic photo-curing adhesive to produce a VA liquid crystal cell. .

(4) Evaluation of liquid crystal orientation, voltage holding ratio, and heat resistance About the VA type liquid crystal cell manufactured in the above (3), when the liquid crystal orientation was evaluated in the same manner as (5) of Example 3-1, The liquid crystal orientation of this liquid crystal cell was “good”. Further, the voltage holding ratio (VHR _BF ) is measured in the same manner as (6) in Example 3-1, and the heat resistance (voltage before and after applying thermal stress) is measured in the same manner as (7) in Example 3-1. The rate of change in retention was evaluated. As a result, VHR _BF was 99.2%. Further, ΔVHR was 2.4%, and the heat resistance was judged as “good”.

[Example 3-8: Retardation film]
(1) Preparation of liquid crystal aligning agent 100 parts by weight of the polymer (PA-2) obtained in Example 2-2 and 5 parts by weight of the polyorganosiloxane (S-1) obtained in Synthesis Example 3 were mixed with NMP and BC. To a solution having a solid content concentration of 3.5% by weight. A liquid crystal aligning agent was prepared by filtering this solution through a filter having a pore size of 0.2 μm.
(2) Production of retardation film The liquid crystal aligning agent prepared above was applied to one surface of a TAC film as a substrate using a bar coater, and baked in an oven at 120 ° C for 2 minutes to have a film thickness of 100 nm. A coating film was formed. Next, the surface of the coating film was irradiated perpendicularly from the substrate normal line with polarized ultraviolet rays of 10 mJ / cm ² containing an emission line of 313 nm using a Hg—Xe lamp and a Grand Taylor prism. Next, the polymerizable liquid crystal (RMS03-013C, manufactured by Merck & Co., Inc.) was filtered through a filter having a pore size of 0.2 μm, and this polymerizable liquid crystal was applied onto the coated film after light irradiation by a bar coater. A coating film was formed. After baking for 1 minute in an oven adjusted to a temperature of 50 ° C., an unpolarized ultraviolet ray containing 365 nm emission line was irradiated at 1,000 mJ / cm ² from a direction perpendicular to the coating surface using an Hg-Xe lamp. A retardation film was produced by curing a polymerizable liquid crystal to form a liquid crystal layer.

(3) Evaluation of liquid crystal orientation About the retardation film manufactured by said (2), liquid crystal orientation is observed by observing the presence or absence of an abnormal domain by visual observation under crossed Nicols and a polarizing microscope (magnification 2.5 times). evaluated. The evaluation was that the alignment was good visually and the abnormal domain was not observed with a polarizing microscope. The liquid crystal alignment was “good”. The abnormal domain was not observed with the visual microscope, but the abnormal domain was observed with a polarizing microscope. The case where the liquid crystal orientation was “possible”, and the case where an abnormal domain was observed visually and with a polarizing microscope was regarded as “Poor”. As a result, this retardation film was evaluated as “good” for liquid crystal alignment.

(4) Adhesiveness Using the retardation film produced in (2) above, the adhesiveness of the coating film formed with the liquid crystal aligning agent to the substrate was evaluated. First, using an equally spaced spacer with a guide, a cutter knife was used to cut from the surface on the liquid crystal layer side of the retardation film to form 10 × 10 lattice patterns in a range of 1 cm × 1 cm. The depth of each cut was made to reach the middle of the substrate thickness from the surface of the liquid crystal layer. Next, after attaching a cellophane tape so as to cover the entire surface of the lattice pattern, the cellophane tape was peeled off. The notches in the lattice pattern after peeling were observed visually under crossed Nicols to evaluate the adhesion. The evaluation was that the adhesion was “good” when no peeling was observed at the portion along the cut line and at the intersection of the lattice pattern, and the number of lattices where peeling was observed in the above portion was the number of the entire lattice pattern. On the other hand, when the amount is less than 15%, the adhesion is “possible”, and when the number of lattices where peeling is observed in the above portion is 15% or more with respect to the total number of lattice patterns, the adhesion is “bad”. went. As a result, this retardation film had good adhesion.

  DESCRIPTION OF SYMBOLS 10 ... Liquid crystal display element, 11a, 11b ... Glass substrate, 12 ... Liquid crystal aligning film, 13 ... Top electrode, 14 ... Insulating layer, 15 ... Bottom electrode, 16 ... Liquid crystal layer

Claims (9)

Reaction of at least one tetracarboxylic acid derivative selected from the group consisting of tetracarboxylic dianhydride, tetracarboxylic acid diester compound, and tetracarboxylic acid diester dihalide with a diamine containing a compound represented by the following formula (1) A liquid crystal aligning agent containing at least one polymer (P) selected from the group consisting of a polyamic acid, a polyamic acid ester, and a polyimide obtained by heating.

(In the formula (1), R ^A is a divalent having an oxygen atom or a sulfur atom at least at any position between the carbon-carbon bond of the hydrocarbon group having 1 to 30 carbon atoms and the position adjacent to the hydrocarbon group. And at least one hydrogen atom of the hydrocarbon group may be substituted with a halogen atom, X ¹ and X ² are each independently an oxygen atom or an alkanediyl group having 1 to 10 carbon atoms. , An alkenediyl group having 2 to 10 carbon atoms, an ester group or an amide group, provided that X ¹ and X ² are oxygen atoms, and R ^A is —O—R ¹ —O— (R ¹ is carbon number 1). In the case of the alkanediyl group of ˜18), the case where the tetracarboxylic acid derivative is 1,2,3,4-cyclobutanetetracarboxylic dianhydride is excluded.) The liquid crystal aligning agent of Claim 1 whose diamine represented by the said Formula (1) is a diamine represented by a following formula (1-1).

(In the formula (1-1), ^{R 2} is a divalent hydrocarbon group having 1 to 30 carbon atoms, ^{X 1} and ^{X 2} each independently represent an oxygen atom, alkanediyl having from 1 to 10 carbon atoms Group, an alkenediyl group having 2 to 10 carbon atoms, an ester group or an amide group, X ³ is an oxygen atom or a sulfur atom, and X ⁴ is a single bond, an oxygen atom or a sulfur atom, provided that X ¹ , X ² , X ³ and X ⁴ are oxygen atoms and R ² is an alkanediyl group having 1 to 18 carbon atoms, the tetracarboxylic acid derivative is 1,2,3,4-cyclobutanetetracarboxylic acid Except for dianhydrides.) The liquid crystal aligning agent of Claim ² whose said R2 is a C1-C11 alkanediyl group. The tetracarboxylic acid derivative is 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro. -5- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl -5- (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [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 Acid anhydrides 3, 5, - tricarboxy-2-carboxymethyl-norbornane -2: 3,5: 6-dianhydride, 4,9-dioxatricyclo [5.3.1.0 ^{2, 6]} undecane -3,5,8, At least selected from the group consisting of 10-tetraone, bicyclo [3.3.0] octane-2,4,6,8-tetracarboxylic dianhydride, ethylenediaminetetraacetic acid dianhydride, and pyromellitic dianhydride. The liquid crystal aligning agent as described in any one of Claims 1-3 containing 1 type.   The liquid crystal aligning agent as described in any one of Claims 1-4 in which the said polymer (P) has a side chain structure which has a pretilt angle expression ability.   The liquid crystal aligning film formed using the liquid crystal aligning agent as described in any one of Claims 1-5.   A liquid crystal display device comprising the liquid crystal alignment film according to claim 6.   A retardation film comprising the liquid crystal alignment film according to claim 6. Applying the liquid crystal aligning agent according to any one of claims 1 to 5 on a substrate to form a coating film;
Irradiating the coating film with light;
A method of producing a retardation film, comprising: applying a polymerizable liquid crystal on the coating film after the light irradiation and curing the liquid crystal.

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