JP2018081225A - Liquid crystal alignment agent, method for manufacturing liquid crystal device, liquid crystal alignment film, liquid crystal device, and polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a PSA mode liquid crystal display device that can express a high voltage holding ratio even after irradiation of a liquid crystal cell with light, and reduces the occurrence of afterimages.SOLUTION: A specific polymer having a specific structure is made contained in a liquid crystal alignment agent for a PSA mode liquid crystal display device.SELECTED DRAWING: None

Description

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

  Conventionally, as a liquid crystal display element, various drive systems having different electrode structures and physical properties of liquid crystal molecules to be used have been developed. For example, TN type, STN type, VA type, in-plane switching type (IPS type), etc. Various liquid crystal display elements are known. These liquid crystal display elements have a liquid crystal alignment film for aligning liquid crystal molecules. As materials for the liquid crystal alignment film, for example, polyamic acid, polyamic acid ester, polyimide, polyester, polyorganosiloxane, and the like are known.

  In recent years, a PSA (Polymer Sustained Alignment) mode has been proposed as a new driving mode for controlling the alignment of liquid crystal molecules in a liquid crystal display device. In the PSA mode, a photopolymerizable compound is mixed in a liquid crystal material, a liquid crystal cell is assembled, and then light is applied to the liquid crystal cell in a state where a voltage is applied between a pair of electrodes sandwiching the liquid crystal layer. This is a technique for controlling the molecular orientation of liquid crystal molecules by polymerizing a polymerizable compound. According to this technique, there is an advantage that the viewing angle can be increased and the response speed can be increased.

  On the other hand, in the PSA mode, when the amount of light irradiation is insufficient, an unreacted photopolymerizable compound remains in the liquid crystal layer, and image burn-in (afterimage) is likely to occur due to the unreacted material. Further, if the amount of light irradiation is increased in order to completely react the photopolymerizable compound, the quality of the liquid crystal molecules and the liquid crystal alignment film may be deteriorated, and the display quality of the panel may be deteriorated. In order to eliminate such inconveniences, various techniques for reducing the amount of the photopolymerizable compound remaining in the liquid crystal layer without increasing the light irradiation amount have been proposed (see, for example, Patent Document 1). This Patent Document 1 discloses that a liquid crystal compound having a terphenyl ring structure (hereinafter also referred to as “terphenyl liquid crystal”) is contained in a liquid crystal layer.

  Furthermore, in recent years, further speed-up response of PSA type liquid crystal panels has been studied. As such a technique, a monofunctional liquid crystal compound having one of an alkenyl group and a fluoroalkenyl group (hereinafter referred to as “alkenyl”). Attempts have been made to introduce a liquid crystal layer into a liquid crystal layer (see, for example, Patent Documents 2 to 4).

International Publication No. 2009/050869 JP 2010-285499 A JP-A-9-104644 JP-A-6-108053

  However, even when terphenyl liquid crystal is introduced into the liquid crystal layer, there are still many unreacted photopolymerizable compounds remaining after light irradiation, and there is room for further improvement in terms of afterimage characteristics. In addition, a liquid crystal display device using an alkenyl liquid crystal can increase the response speed, but has a voltage holding ratio compared to a liquid crystal cell that does not include an alkenyl liquid crystal in a liquid crystal layer by light irradiation to the liquid crystal cell. It has become clear that the decline of From the viewpoint of further improving the display quality of the liquid crystal display element, it is required to suppress the decrease in the voltage holding ratio due to light irradiation as much as possible.

  The present invention has been made in view of the above problems, and it is a main object of the present invention to provide a liquid crystal aligning agent that can exhibit a high voltage holding ratio even after light irradiation to a liquid crystal cell and can obtain a liquid crystal display element that hardly causes an afterimage. And

As a result of intensive studies to achieve the above-described problems of the prior art, the present inventors have made a group consisting of a polysiloxane having a specific partial structure and a polyamic acid, a polyamic acid ester, a polyimide, and a polyamide having a specific partial structure. The present inventors have found that the above-mentioned problems can be solved by a liquid crystal aligning agent containing at least one polymer selected from the group consisting of: Specifically, the present invention provides the following liquid crystal aligning agent, liquid crystal element manufacturing method, liquid crystal alignment film, liquid crystal element, and polymer. Specifically, the following means are provided.
<1> Polysiloxane having at least one partial structure selected from the group represented by the following formula (1) and the following formulas (2) to (9), and
Selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, and selected from the group represented by the following formula (1-1), the following formula (1-2), and the following formulas (2) to (9). A polymer having at least one partial structure,
A liquid crystal aligning agent containing at least one polymer selected from the group consisting of:

(In the formulas (1) to (9),
X represents each independently a halogen atom, a hydroxyl group, a cyano group, a nitro group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms,
a is an integer of 0 to 4, b is an integer of 0 to 3, c is an integer of 0 to 5,
R ₁ , R ₂ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, or 1 to 20 carbon atoms. R ₁ represents an alkoxy group, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and an alkenyloxy group having 2 to 12 carbon atoms, R ₁ And R ₂ may be linked to form a 3- to 6-membered cyclic alkane or heterocyclic group, and an alkyl group, alkoxy group, aryl group, arylalkyl group, alkenyl group, alkenyloxy group, cyclic alkyl group, The heterocyclic group may have a substituent,
R ₃ represents a hydroxyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or any group represented by the following formula (10), and the alkoxy group may have a substituent,

(In Formula (10), Y ₂ is a methylene group, —NR, an oxygen atom, or a sulfur atom, R is independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X and c are the above Is the same.)
* Represents a bond. )

(In Formula (1-1) and (Formula 1-2),
X, a, R ₁ , R ₂ , R ₃ , * are the same as above,
d is an integer of 1 to 5,
R ₉ and R ₁₀ are each independently a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a carbon atom. Represents an arylalkyl group having 7 to 30 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and an alkenyloxy group having 2 to 12 carbon atoms, and R ₁ and R ₂ are linked to form a 3- to 6-membered cyclic alkane or A heterocyclic group may be formed, and an alkyl group, an alkoxy group, an aryl group, an arylalkyl group, an alkenyl group, an alkenyloxy group, a cyclic alkyl group, and a heterocyclic group may have a substituent,
At least one selected from the group of R ₉ and R ₁₀ represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkenyl group having 2 to 12 carbon atoms, or an alkenyloxy group having 2 to 12 carbon atoms. )
Applying the liquid crystal aligning agent of <1> above to the conductive film of a pair of substrates having a conductive film to form a coating film;
A step of constructing a liquid crystal cell by arranging the pair of substrates on which the coating film is formed so as to face each other with the coating film facing each other through a liquid crystal layer;
Irradiating the liquid crystal cell with light while applying a voltage between the conductive films of the pair of substrates.

  By producing a liquid crystal alignment film using the liquid crystal aligning agent, a high voltage holding ratio can be exhibited even after light irradiation with respect to the liquid crystal cell, and an afterimage can be hardly generated. Further, in the obtained liquid crystal display element, the response speed of the liquid crystal molecules is fast, and the display quality can be improved.

The figure which shows the electrode pattern of the transparent electrode film used in the Example and the comparative example. The figure which shows the electrode pattern of the transparent electrode film used in the Example and the comparative example. The figure which shows the electrode pattern of the transparent electrode film used in the Example and the comparative example.

  Below, each component contained in the liquid crystal aligning agent of this indication and the other component arbitrarily mix | blended as needed are demonstrated.

In the present specification, the “main chain” of a polymer refers to a “trunk” portion comprising the longest chain of atoms in the polymer. It is allowed that the “trunk” portion includes a ring structure. The “hydrocarbon group” is a concept including a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. The “chain hydrocarbon group” means a linear or branched hydrocarbon group that does not include a cyclic structure and is composed only of a chain structure. The “alicyclic hydrocarbon group” means a hydrocarbon group containing only an alicyclic hydrocarbon structure as a ring structure. However, it is not necessary to be constituted only by the structure of the alicyclic hydrocarbon, and a part thereof may have a chain structure. “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.
<Polymer (A)>
The polymer (A) is a polysiloxane having at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9), and
Selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, and selected from the group represented by the above formula (1-1), the above formula (1-2) and the above formulas (2) to (9) A polymer having at least one partial structure,
A polysiloxane having at least one partial structure selected from the group represented by the above formula (1), formula (3), formula (4) and formula (5), and
It is selected from the group consisting of polyamic acid, polyamic acid ester, polyimide and polyamide, and is represented by the above formula (1-1), formula (1-2), formula (3), formula (4) and formula (5). A polymer having at least one partial structure selected from the group described above is preferred.
In addition, a polymer (A) may be used individually by 1 type, and may be used in combination of 2 or more type.
The substituent of the alkyl group, alkoxy group, alkenyl group, alkenyloxy group, cyclic alkyl group, and heterocyclic group may be a hydroxyl group, a carboxyl group, a halogen atom, a cyano group, or a nitro group,
The substituent for the aryl group may be an alkyl group having 1 to 4 carbon atoms, a hydroxyl group, a carboxyl group, a halogen atom, a cyano group or a nitro group,
As the substituent of the arylalkyl group, an alkyl group having 1 to 4 carbon atoms, a hydroxyl group, an alkoxy group having 1 to 4 carbon atoms, an amino group, an alkylthio group having 1 to 4 carbon atoms, a carboxyl group, a halogen atom, It may be a cyano group or a nitro group.
The alkyl group, alkoxy group, alkenyl group, and cyclic alkyl group may have a branched structure.
Examples of the alkyl group having 1 to 20 carbon atoms include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, amyl, isoamyl, t-amyl, hexyl, heptyl, octyl, isooctyl, 2-ethylhexyl, t-octyl, nonyl, isononyl, decyl, isodecyl, undecyl, dodecyl, tetradecyl, hexadecyl, octadecyl, icosyl, cyclopentyl, cyclopentylmethyl, cyclopentylethyl, cyclohexyl, cyclohexylmethyl, cyclohexylethyl and the like.
Examples of the alkoxy group having 1 to 20 carbon atoms include methoxy, ethoxy, propyloxy, isopropyloxy, butoxy and the like.
Examples of the aryl group having 6 to 30 carbon atoms include a phenyl group, a naphthyl group, and a biphenylene group.
Examples of the arylalkyl group having 7 to 30 carbon atoms include benzyl, α-methylbenzyl, α, α-dimethylbenzyl, phenylethyl, 9-fluorenylmethyl and the like.
Examples of the alkenyl group having 2 to 12 carbon atoms include vinyl group, 1-propenyl group, 2-propenyl group, isopropenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1-octenyl group, 1 -Groups such as a decenyl group.
Examples of the alkenyloxy group having 2 to 12 carbon atoms include groups such as vinyloxy group and 1-propenyloxy group.
Examples of the 3- to 6-membered cyclic alkane include a cyclopentane ring and a cyclohexane ring.
Examples of the heterocyclic group include groups in which one of the carbon atoms of the cyclic alkane is replaced with a nitrogen atom.
[Polyorganosiloxane]
A polysiloxane having at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9) as the polymer (A) (hereinafter also referred to as “polyorganosiloxane (A)”) Can be obtained, for example, by hydrolyzing and condensing a hydrolyzable silane compound. Specifically, the following [1] or [2] can be mentioned.
[1] An epoxy group-containing polyorganosiloxane is synthesized by hydrolytic condensation of a hydrolyzable silane compound (ms-1) having an epoxy group or a mixture of the silane compound (ms-1) and another silane compound. Then, the resulting epoxy group-containing polyorganosiloxane and a carboxylic acid having at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9) (hereinafter “ A specific carboxylic acid ”),
[2] Hydrolyzable silane compound (ms-2) having at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9), or the silane compound And a method of hydrolyzing and condensing a mixture of (ms-2) and other silane compounds. Among these, the method [1] is simple and has at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9) in the polyorganosiloxane. This is preferable because the introduction rate can be increased.

  Specific examples of the silane compound (ms-1) include, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropyl. Methyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (3,4-epoxycyclohexyl) propyltrimethoxysilane, etc. Can be mentioned. As the silane compound (ms-1), one of these can be used alone, or two or more can be used in combination.

  Specific examples of the silane compound (ms-2) include compounds represented by the following formulas, for example.

As the silane compound (ms-2), one of these can be used alone, or two or more can be mixed and used.

Other silane compounds are not particularly limited as long as they are hydrolyzable silane compounds. For example, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimethyldimethoxysilane, dimethyl Alkoxysilanes such as diethoxysilane;
3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N- (3-cyclohexylamino) propyltri Nitrogen / sulfur-containing alkoxysilanes such as methoxysilane and N-2- (aminoethyl) -3-aminopropyltrimethoxysilane;
3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 6- (meth) acryloyloxyhexyltrimethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, 3- (Meth) acryloxypropylmethyldiethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, alkoxysilanes containing unsaturated bonds such as p-styryltrimethoxysilane; in addition to trimethoxysilylpropyl succinic anhydride Can be mentioned. Other silane compounds can be used alone or in combination of two or more.

  The hydrolysis / condensation reaction of the silane compound is carried out by reacting one or more of the above silane compounds with water, preferably in the presence of an appropriate catalyst and an organic solvent.

  In the method of [1] above, a sufficient amount of group at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9) is introduced into the side chain of the polymer. From the viewpoint of suppressing side reactions caused by an excessive amount of epoxy groups while enabling the epoxy group-containing polyorganosiloxane, the epoxy equivalent is preferably 100 to 10,000 g / mol, and 150 More preferably, it is -1,000 g / mol. Therefore, in synthesizing the epoxy group-containing polyorganosiloxane, it is preferable to adjust the use ratio of the silane compound (ms-1) so that the epoxy equivalent of the obtained polyorganosiloxane is in the above range. In the hydrolysis / condensation reaction, the proportion of water used is preferably 0.5 to 100 mol, more preferably 1 to 30 mol, per 1 mol of the silane compound (total amount).

  Examples of the catalyst used in the hydrolysis / condensation reaction include acids, alkali metal compounds, organic bases, titanium compounds, zirconium compounds and the like. The amount of catalyst used varies depending on the type of catalyst, reaction conditions such as temperature, and should be set as appropriate. For example, it is preferably 0.01 to 3 times the total amount of the silane compound. More preferably, it is 0.05-1 times mole.

  Examples of the organic solvent used in the above hydrolysis / condensation reaction include hydrocarbons, ketones, esters, ethers, alcohols and the like. Among these, it is preferable to use a water-insoluble or poorly water-soluble organic solvent. The use ratio of the organic solvent is preferably 10 to 10,000 parts by weight, and more preferably 50 to 1,000 parts by weight with respect to a total of 100 parts by weight of the silane compounds used in the reaction.

  The hydrolysis / condensation reaction is preferably carried out by heating with, for example, an oil bath. In the hydrolysis / condensation reaction, the heating temperature is preferably 130 ° C. or lower, more preferably 40 to 100 ° C. The heating time is preferably 0.5 to 12 hours, and more preferably 1 to 8 hours. During heating, the mixture may be stirred or placed under reflux. Moreover, after completion | finish of reaction, it is preferable to wash | clean the organic-solvent layer fractionated from the reaction liquid with water. In this washing, washing with water containing a small amount of salt (for example, an aqueous ammonium nitrate solution of about 0.2% by weight) is preferable in that the washing operation is facilitated. Washing is performed until the aqueous layer after washing becomes neutral, and then the organic solvent layer is dried with a desiccant such as anhydrous calcium sulfate or molecular sieve as necessary, and then the solvent is removed to remove the solvent. The polyorganosiloxane can be obtained. The method for synthesizing the polyorganosiloxane is not limited to the hydrolysis / condensation reaction described above, and may be performed by, for example, a method in which a hydrolyzable silane compound is reacted in the presence of oxalic acid and alcohol.

  In the method [1] above, the epoxy group-containing polyorganosiloxane obtained by the above reaction is then reacted with a specific carboxylic acid. As a result, the epoxy group of the epoxy group-containing polyorganosiloxane reacts with the carboxylic acid, and at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9). Can be obtained in the side chain.

  Specific examples of the specific carboxylic acid include compounds represented by the following formulas, for example.

  In addition, specific carboxylic acid can be used individually by 1 type or in combination of 2 or more types.

  The content ratio of at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9) in one molecule of the polyorganosiloxane sufficiently exhibits the effects of the present invention. From the viewpoint of the above, it is preferably 3 to 80 mol%, more preferably 5 to 75 mol%, still more preferably 10 to 70 mol%, based on the silicon atom of the polyorganosiloxane. . Therefore, when the polyorganosiloxane (A) is synthesized, the content ratio of at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9) is in the above range. It is preferable to select the ratio of the specific carboxylic acid used.

  In synthesizing the polyorganosiloxane (A), the carboxylic acid used for the reaction with the epoxy group-containing polyorganosiloxane may be only the specific carboxylic acid, but other carboxylic acids other than the specific carboxylic acid may be used in combination. Good.

  The other carboxylic acid is not particularly limited as long as it does not have at least one partial structure selected from the group represented by the above formula (1) and the above formulas (2) to (9). Examples thereof include carboxylic acids having the liquid crystal orientation group. Other carboxylic acids can be used alone or in combination of two or more.

  The proportion of the carboxylic acid to be reacted with the epoxy group-containing polyorganosiloxane is preferably 0.001 to 1.5 mol, based on 1 mol of the total epoxy groups of the polyorganosiloxane, 0.01 to 1 More preferably, it is 0.0 mol.

  The ratio of the other carboxylic acid used is preferably 80 mol% or less, more preferably 50 mol% or less, based on the total amount of carboxylic acid to be reacted with the epoxy group-containing polyorganosiloxane.

  The reaction between the epoxy group-containing polysiloxane and the carboxylic acid can be preferably carried out in the presence of a catalyst and an organic solvent. As said catalyst, a well-known compound etc. can be used as what is called a hardening accelerator which accelerates | stimulates reaction of an organic base and an epoxy compound, for example. Of these, tertiary organic amines or quaternary organic amines are preferred. The ratio of the catalyst used is preferably 100 parts by weight or less, more preferably 0.01 to 100 parts by weight, and still more preferably 0.1 to 20 parts by weight with respect to 100 parts by weight of the epoxy group-containing polysiloxane.

  Examples of the organic solvent used in the above reaction include hydrocarbons, ethers, esters, ketones, amides, alcohols and the like. Among these, from the viewpoints of solubility of raw materials and products, and ease of purification of the product, it is preferably at least one selected from the group consisting of ethers, esters and ketones, and specific examples of particularly preferred solvents Examples thereof include 2-butanone, 2-hexanone, methyl isobutyl ketone, and butyl acetate. The organic solvent is preferably used in such a ratio that the solid content concentration (the ratio of the total weight of components other than the solvent in the reaction solution to the total weight of the solution) is 0.1% by weight or more, It is more preferable to use it at a ratio of 5 to 50% by weight.

  The reaction temperature in the above reaction is preferably 0 to 200 ° C, more preferably 50 to 150 ° C. The reaction time is preferably 0.1 to 50 hours, more preferably 0.5 to 20 hours. Moreover, after completion | finish of reaction, it is preferable to wash | clean the organic-solvent layer fractionated from the reaction liquid with water. After washing with water, the organic solvent layer is dried with an appropriate desiccant as necessary, and then the solvent is removed, so that the organic solvent layer is selected from the group represented by the above formula (1) and the above formulas (2) to (9). A polyorganosiloxane having at least one partial structure in the side chain can be obtained.

Regarding the polyorganosiloxane (A), the polystyrene-equivalent weight average molecular weight (Mw) measured by GPC is preferably in the range of 100 to 50,000, and more preferably in the range of 200 to 10,000. When the weight average molecular weight of the polyorganosiloxane (A) is in the above range, it is easy to handle when producing a liquid crystal alignment film, and the obtained liquid crystal alignment film has sufficient material strength and characteristics.
[Polyamic acid]
A polyamic acid having at least one partial structure selected from the group represented by the above formula (1-1), the above formula (1-2) and the above formulas (2) to (9) as the polymer (A) ( (Hereinafter also referred to as “polyamic acid (A)”) is represented by, for example, tetracarboxylic dianhydride, the above formula (1-1), the above formula (1-2), and the above formulas (2) to (9). It can be obtained by reacting with a diamine having at least one partial structure selected from the group described above.
(Tetracarboxylic dianhydride)
Examples of tetracarboxylic dianhydrides used for the synthesis of polyamic acid (A) include aliphatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, and aromatic tetracarboxylic dianhydrides. be able to. 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, 5- (2,5-di Oxotetrahydrofuran-3-yl) -3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, 5- (2,5-dioxotetrahydrofuran-3-yl) -8 -Methyl-3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro -3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3 , 5,6-To Carboxy-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 and the like;
Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 4,4 ′-(hexafluoroisopropylidene) diphthalic anhydride, and the following formula (B-1)

(In Formula (B-1), X ¹ and X ² are each independently a single bond, an oxygen atom, a sulfur atom, —CO—, * —COO—, * —OCO—, * —CO—NR ²² —, * —NR ²² —CO— (wherein R ²² is a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms, “*” represents a bond to R ²¹ ). ²¹ is an alkanediyl group having 1 to 10 carbon atoms, a divalent group containing —O— between carbon-carbon bonds of the alkanediyl group, a cyclohexylene group, a phenylene group or a biphenylene group.
In addition, the tetracarboxylic dianhydrides described in JP 2010-97188 A can be used.

Specific examples of the alkanediyl group having 1 to 10 carbon atoms of R ²¹ in the formula (B-1) include, for example, a methylene group, an ethylene group, a propylene group, a butanediyl group, a pentanediyl group, a hexanediyl group, a heptanediyl group, and octane. A diyl group, a nonanediyl group, a decanediyl group, etc. are mentioned. In the divalent group containing —O— between the carbon-carbon bonds of the alkanediyl group, the number of oxygen atoms may be one or two or more.

  Specific examples of the compound represented by the formula (B-1) include, for example, compounds represented by the following formulas (B-1-1) to (B-1-4).

  In addition, the said tetracarboxylic dianhydride can be used individually by 1 type or in combination of 2 or more types.

The tetracarboxylic dianhydride used for the synthesis includes 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dihydrate from the viewpoint of affinity with liquid crystal and the like. Anhydride, 5- (2,5-dioxotetrahydrofuran-3-yl) -3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, 5- (2,5 -Dioxotetrahydrofuran-3-yl) -8-methyl-3a, 4,5,9b-tetrahydronaphtho [1,2-c] furan-1,3-dione, bicyclo [3.3.0] octane-2 , 4,6,8-tetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride, p-phenylenebis (trimellitic acid monoester anhydride), It is preferable to contain at least one compound selected from the group consisting of lomellitic dianhydride and a compound represented by the above formula (B-1). The amount of these preferred tetracarboxylic dianhydrides used (the total amount when two or more are used) is 5 mol% or more based on the total amount of tetracarboxylic dianhydrides used for the synthesis of polyamic acid. Preferably, the content is 10 mol% or more, more preferably 20 mol% or more.
(Diamine)
It has at least one partial structure selected from the group represented by the above formula (1-1), the above formula (1-2) and the above formulas (2) to (9) used for the synthesis of the polyamic acid (A). Diamine (hereinafter sometimes referred to as specific diamine)
Specific examples of the compound include compounds represented by the following formulas, for example.

  In the synthesis of the polyamic acid (A), a specific diamine may be used alone, or a diamine other than the specific diamine (hereinafter referred to as “other diamine”) may be used in combination.

Examples of such other diamines include aliphatic diamines, alicyclic diamines, aromatic diamines, and diaminoorganosiloxanes. Specific examples of these diamines include aliphatic diamines such as metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, and 1,3-bis (aminomethyl) cyclohexane. ;
Examples of alicyclic diamines include 1,4-diaminocyclohexane, 4,4′-methylenebis (cyclohexylamine) and the like;
Examples of the aromatic diamine include dodecanoxydiaminobenzene, tetradecanoxydiaminobenzene, pentadecanoxydiaminobenzene, hexadecanoxydiaminobenzene, octadecanoxydiaminobenzene, 3,5-diaminobenzoic acid 2- ( Methacryloyloxy) ethyl, cholestanyloxydiaminobenzene, cholesteryloxydiaminobenzene, cholestanyl diaminobenzoate, cholesteryl diaminobenzoate, lanostannyl diaminobenzoate, 3,6-bis (4-aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4-butylcyclohexane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4 -F Tylcyclohexane, 1,1-bis (4-((aminophenoxy) methyl) phenyl) -4-heptylcyclohexane, N- (2,4-diaminophenyl) -4- (4-heptylcyclohexyl) benzamide, E-1)

(In Formula (E-1), X ^I and X ^II are each independently a single bond, —O—, * —COO— or * —OCO— (where “*” represents a bond with X ^I). R ^I is an alkanediyl group having 1 to 3 carbon atoms, R ^II is a single bond or an alkanediyl group having 1 to 3 carbon atoms, a is 0 or 1, and b is 0 ) Is an integer of ˜2, c is an integer of 1 to 20, and d is 0 or 1. However, a and b are not 0 at the same time.)
Oriented group-containing diamine such as a compound represented by:
p-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfide, 4-aminophenyl-4′-aminobenzoate, 4,4′-diaminoazobenzene, 3,5-diaminobenzoic acid, 2 , 4-Diaminobenzoic acid, 2,6-diaminopyridine, 1,5-bis (4-aminophenoxy) pentane, 1,7-bis (4-aminophenoxy) heptane, bis [2- (4-aminophenyl) Ethyl] hexanedioic acid, N, N-bis (4-aminophenyl) methylamine, 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) fur Nyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 4,4 ′-(p-phenylenediisopropylidene) Bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl and the like;
Examples of the diaminoorganosiloxane include 1,3-bis (3-aminopropyl) -tetramethyldisiloxane; and the diamines described in JP-A 2010-97188 can be used.

Examples of the divalent group represented by “—X ^I — (R ^I —X ^II ) _d —” in the above formula (E-1) include alkanediyl groups 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. Examples of the group “—C _c H _{2c + 1} ” include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, a dodecyl group, a tridecyl group, and a tetradecyl group. Group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, eicosyl group and the like, and these are preferably linear. The two amino groups in the diaminophenyl group are preferably in the 2,4-position or 3,5-position with respect to other groups.

  Specific examples of the compound represented by the formula (E-1) include, for example, compounds represented by the following formulas (E-1-1) to (E-1-4).

  When applied to a liquid crystal aligning agent for a TN type, STN type or vertical alignment type liquid crystal display element, a group capable of exhibiting characteristics for controlling the alignment of liquid crystal molecules in the side chain of the polyamic acid (hereinafter referred to as “liquid crystal alignment group”) May also be introduced). Examples of the liquid crystal aligning group include an alkyl group having 4 to 20 carbon atoms, a fluoroalkyl group having 4 to 20 carbon atoms, an alkoxy group having 4 to 20 carbon atoms, a group having a steroid skeleton having 17 to 51 carbon atoms, and a polycyclic ring. Examples thereof include a group having a structure. The polyamic acid having a liquid crystal alignment group can be obtained, for example, by polymerization including an alignment group-containing diamine in the monomer composition. When using orientation group containing diamine, it is preferable that the compounding quantity shall be 3 mol% or more with respect to all the diamines used for a synthesis | combination from a liquid crystal aligning viewpoint, and shall be 5-70 mol%. Is more preferable.

  When providing the liquid crystal aligning ability with the photo-alignment method with respect to the coating film formed with the liquid crystal aligning agent, it is good also considering at least one part of polyamic acid (A) as a polymer which has a photo-alignment structure. As a specific example of the photoalignment structure, a group exhibiting photoalignment by photoisomerization, photodimerization, photolysis, or the like can be employed. Specifically, for example, an azo-containing group containing an azo compound or derivative thereof as a basic skeleton, a cinnamic acid-containing group containing cinnamic acid or a derivative thereof as a basic skeleton, or a chalcone-containing group containing chalcone or a derivative thereof as a basic skeleton A benzophenone-containing group containing benzophenone or a derivative thereof as a basic skeleton, a coumarin-containing group containing coumarin or a derivative thereof as a basic skeleton, a cyclobutane-containing structure containing cyclobutane or a derivative thereof as a basic skeleton, bicyclo [2.2.2 ] Bicyclo [2.2.2] octene-containing structure containing octene or a derivative thereof as a basic skeleton, the following formula (4)

(In Formula (4), X ⁴ is a sulfur atom, an oxygen atom or —NH—. “*” Represents a bond, respectively, provided that at least one of two “*” is bonded to an aromatic ring. doing.)
An ester group-containing structure containing a partial structure represented by the above as a basic skeleton, and the like.

  The polyamic acid having a photoalignment structure can be obtained, for example, by polymerization containing at least one of a tetracarboxylic dianhydride having a photoalignment structure and a diamine having a photoalignment structure as a raw material. In this case, the proportion of the monomer having a photo-alignment structure is preferably 20 mol% or more based on the total amount of monomers used for the synthesis of the polyamic acid, from the viewpoint of improving the photoreactivity. It is more preferable to set it to -80 mol%.

In synthesizing the polyamic acid (A), the specific diamine is used in an amount of 1 mol% or more with respect to the total amount of diamines used in the synthesis from the viewpoint of sufficiently achieving the effects of the present invention. It is preferably 5 mol% or more, more preferably 10 mol% or more. Moreover, although the upper limit of the usage rate of specific diamine is not restrict | limited in particular, when using other diamine, it is preferable to set it as 90 mol% or less, and it is more preferable to set it as 80 mol% or less.
(Synthesis of polyamic acid)
The polyamic acid can be obtained by reacting the tetracarboxylic dianhydride and diamine as described above with a molecular weight modifier as necessary. The ratio of the tetracarboxylic dianhydride and the diamine used in the polyamic acid synthesis reaction is 0.2 to 2 for the tetracarboxylic dianhydride acid anhydride group to 1 equivalent of the amino group of the diamine. The ratio which becomes an equivalent is preferable, and the ratio which becomes 0.3-1.2 equivalent is more preferable.

  Examples of the molecular weight modifier include acid monoanhydrides such as maleic anhydride, phthalic anhydride and itaconic anhydride, monoamine compounds such as aniline, cyclohexylamine and n-butylamine, and monoisocyanate compounds such as phenyl isocyanate and naphthyl isocyanate. Can be mentioned. The use ratio of the molecular weight modifier 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.

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

  Examples of the organic solvent used in the reaction include aprotic polar solvents, phenol solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons, and the like. Among these organic solvents, one or more selected from the group consisting of an aprotic polar solvent and a phenolic solvent (first group organic solvent), or one or more selected from the first group of organic solvents And a mixture of at least one selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons (second-group organic solvent). In the latter case, the proportion of the second group organic solvent used is preferably 50% by weight or less, more preferably 40% by weight, based on the total amount of the first group organic solvent and the second group organic solvent. Or less, more preferably 30% by weight or less.

  Particularly preferred organic solvents are N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide, m-cresol, xylenol. And at least one selected from the group consisting of halogenated phenols is used as a solvent, or a mixture of one or more of these and another organic solvent is preferably used in the above range. Examples of other organic solvents used at this time include butyl cellosolve, 2-butoxy-1-propanol, and diethylene glycol diethyl ether. The amount of organic solvent used (a) is such that the total amount (b) of tetracarboxylic dianhydride and diamine is 0.1 to 50% by weight based on the total amount (a + b) of the reaction solution. Is preferred.

As described above, a reaction solution obtained by dissolving polyamic acid 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. Isolation and purification of the polyamic acid can be performed according to known methods.
[Polyamic acid ester]
The polyamic acid ester as the polymer (A) is, for example, [I] a method of reacting the polyamic acid (A) obtained by the above synthesis reaction with an esterifying agent, and [II] a tetracarboxylic acid diester and a diamine. It can be obtained by a method of reacting, [III] a method of reacting a tetracarboxylic acid diester dihalide and a diamine, or the like.

  In this specification, “tetracarboxylic acid diester” 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.

  Examples of the esterifying agent used in Method [I] include a hydroxyl group-containing compound, an acetal compound, a halide, an epoxy group-containing compound, and the like. Specific examples thereof include hydroxyl group-containing compounds such as alcohols such as methanol, ethanol and propanol; phenols such as phenol and cresol; and acetal compounds such as N, N-dimethylformamide diethyl acetal, N, N-diethylformamide diethyl acetal and the like; halides such as methyl bromide, ethyl bromide, stearyl bromide, methyl chloride, stearyl chloride, 1,1,1-trifluoro-2-iodoethane and the like; epoxy group-containing Examples of the compound include propylene oxide.

  The tetracarboxylic acid diester used in the method [II] can be obtained, for example, by ring-opening the tetracarboxylic dianhydride exemplified in the synthesis of the polyamic acid with alcohols such as methanol and ethanol. The tetracarboxylic acid derivative used in method [II] may be only a tetracarboxylic acid diester, but may also be used in combination with tetracarboxylic dianhydride. Moreover, as diamine used by method [II], specific diamine may be used independently or other diamine may be used together. The reaction of Method [II] is preferably carried out in an organic solvent in the presence of a suitable dehydration catalyst. As an organic solvent, the organic solvent illustrated as what is used for the synthesis | combination of a polyamic acid can be mentioned. Examples of the dehydration catalyst include 4- (4,6-dimethoxy-1,3,5-triazin-2-yl) -4-methylmorpholinium halide, carbonylimidazole, a phosphorus condensing agent, and the like. The reaction temperature at this time is preferably -20 to 150 ° C, more preferably 0 to 100 ° C. The reaction time is preferably from 0.1 to 24 hours, more preferably from 0.5 to 12 hours.

  The tetracarboxylic acid diester dihalide used in Method [III] can be obtained, for example, by reacting the tetracarboxylic acid diester obtained as described above with an appropriate chlorinating agent such as thionyl chloride. The tetracarboxylic acid derivative used in the method [III] may be only a tetracarboxylic acid diester, but may also be used in combination with a tetracarboxylic dianhydride. Moreover, as diamine used by method [III], specific diamine may be used independently or other diamine may be used together. The reaction of Method [III] is preferably carried out in an organic solvent in the presence of a suitable base. As an organic solvent, the organic solvent illustrated as what is used for the synthesis | combination of a polyamic acid can be mentioned. As the base, for example, tertiary amines such as pyridine and triethylamine; alkali metals such as sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, sodium and potassium can be preferably used. The reaction temperature at this time is preferably -20 to 150 ° C, more preferably 0 to 100 ° C. The reaction time is preferably from 0.1 to 24 hours, more preferably from 0.5 to 12 hours.

The polyamic acid ester as the compound (A) 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. In addition, the reaction solution formed by dissolving the polyamic acid ester may be used for the preparation of the liquid crystal aligning agent as it is, or may be used for the preparation of the liquid crystal aligning agent after isolating the polyamic acid ester contained in the reaction solution. Alternatively, the isolated polyamic acid ester may be purified and then used for the preparation of the liquid crystal aligning agent. Isolation and purification of the polyamic acid ester can be performed according to a known method.
[Polyimide]
The polyimide as the polymer (A) can be obtained, for example, by dehydrating and ring-closing the polyamic acid (A) synthesized as described above to imidize.

  The polyimide may be a completely imidized product obtained by dehydrating and cyclizing all of the amic acid structure of the polyamic acid (A) that is a precursor thereof, and dehydrating and cyclizing only a part of the amic acid structure, A partially imidized product in which a structure and an imide ring structure coexist may be used. The polyimide to be used preferably has an imidization ratio of 20% or more, more preferably 30 to 99%, and still more preferably 40 to 99%. This imidation ratio represents the ratio of the number of imide ring structures to the total of the number of polyimide amic acid structures and the number of imide ring structures in percentage. Here, a part of the imide ring may be an isoimide ring.

  The dehydration ring closure of the polyamic acid (A) is preferably performed by heating the polyamic acid (A) or by dissolving the polyamic acid (A) in an organic solvent, and adding a dehydrating agent and a dehydration ring closure catalyst to this solution. Depending on the heating method. Of these, the latter method is preferred.

  In the method of adding a dehydrating agent and a dehydrating ring-closing catalyst to a polyamic acid solution, as the dehydrating agent, for example, acid anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used. 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 (A). 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 for the dehydration ring-closing reaction include the organic solvents exemplified as those used for the synthesis of the polyamic acid (A). 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 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. In addition, polyimide can also be obtained by imidation of polyamic acid ester.

  The polyamic acid, the polyamic acid ester, and the polyimide as the polymer (A) 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. The solution viscosity (mPa · s) of polyamic acid, polyamic acid ester, and polyimide was 10% by weight with a good solvent (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) of these polymers. Is a value measured at 25 ° C. using an E-type rotational viscometer.

The polystyrene-equivalent weight average molecular weight (Mw) measured by polyamic acid, polyamic acid ester and polyimide gel permeation chromatography (GPC) is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. Moreover, the molecular weight distribution (Mw / Mn) represented by the ratio between Mw and the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is preferably 15 or less, more preferably 10 or less. By being in such a molecular weight range, it is possible to ensure good orientation and stability of the liquid crystal display element.
[polyamide]
The polyamide as the polymer (A) can be obtained, for example, by a method of reacting dicarboxylic acid and diamine. Here, the dicarboxylic acid is preferably subjected to a reaction with a diamine after acid chloride using an appropriate chlorinating agent such as thionyl chloride.

Although it does not restrict | limit especially as dicarboxylic acid used for the synthesis | combination of polyamide, For example, oxalic acid, malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, 2 , Aliphatic dicarboxylic acids such as 1,2-dimethylglutaric acid, 3,3-diethylsuccinic acid, azelaic acid, sebacic acid, suberic acid, fumaric acid, muconic acid;
Dicarboxylic acids having an alicyclic structure such as cyclobutanedicarboxylic acid, 1-cyclobutenedicarboxylic acid, cyclopentanedicarboxylic acid, cyclohexanedicarboxylic acid;
Phthalic acid, isophthalic acid, terephthalic acid, 5-methylisophthalic acid, 5-tert-butylisophthalic acid, 2,5-dimethylterephthalic acid, naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-diphenylmethane Dicarboxylic acid, 4,4′-diphenylpropane dicarboxylic acid, 4,4′-diphenyl ether dicarboxylic acid, 4,4′-carbonyldibenzoic acid, 4-carboxycinnamic acid, p-phenylene diacrylic acid, 3,3′- [4,4 ′-(methylenedi-p-phenylene)] dipropionic acid, 4,4 ′-[4,4 ′-(oxydi-p-phenylene)] dibutyric acid, 3,4-diphenyl-1,2- And dicarboxylic acids having an aromatic ring such as cyclobutanedicarboxylic acid. In addition, dicarboxylic acid can be used individually by 1 type or in combination of 2 or more types.

  The diamine used for the synthesis of the polyamide as the polymer (A) includes a specific diamine. Moreover, you may use other diamine together as needed. A diamine can be used individually by 1 type or in combination of 2 or more types.

  The proportion of the dicarboxylic acid and diamine used in the polyamide synthesis reaction is preferably such that the carboxyl group of the dicarboxylic acid is 0.2 to 2 equivalents relative to 1 equivalent of the amino group of the diamine. A ratio of 1.2 equivalent is more preferable.

  The reaction between a dicarboxylic acid (preferably an acid-chloride dicarboxylic acid) and a diamine is preferably carried out in an organic solvent in the presence of a base. The reaction temperature at this time is preferably 0 ° C to 200 ° C, and more preferably 10 to 100 ° C. The reaction time is preferably 0.5 to 48 hours, and more preferably 1 to 36 hours.

  As the organic solvent used for the reaction, for example, tetrahydrofuran, dioxane, toluene, chloroform, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone and the like can be preferably used. The amount of the organic solvent used is preferably 400 to 900 parts by weight and more preferably 500 to 700 parts by weight with respect to 100 parts by weight of the total amount of dicarboxylic acid and diamine.

  As the base used in the above reaction, for example, tertiary amines such as pyridine, triethylamine, N-ethyl-N, N-diisopropylamine can be preferably used. The amount of the base used is preferably 2 to 4 mol and more preferably 2 to 3 mol with respect to 1 mol of the diamine.

  As described above, a reaction solution obtained by dissolving polyamide is obtained. This reaction solution may be used as it is for the preparation of the liquid crystal aligning agent, and may be used for the preparation of the liquid crystal aligning agent after isolating the polyamide contained in the reaction solution, or after purifying the isolated polyamide. You may use for preparation of a liquid crystal aligning agent. The isolation and purification of the polyamide can be performed according to known methods.

The solution viscosity of the polyamide as the polymer (A) is preferably a solution having a solution viscosity of 10 to 800 mPa · s, when the solution has a concentration of 10% by weight, and a solution of 15 to 500 mPa · s. More preferably, it has a viscosity. Moreover, about the polyamide, the polystyrene conversion weight average molecular weight (Mw) measured by GPC becomes like this. Preferably it is 1,000-500,000, More preferably, it is 5,000-300,000.
<Other ingredients>
The liquid crystal aligning agent which concerns on this invention may contain the other component as needed while containing a polymer (A). Examples of other components that may be blended in the liquid crystal aligning agent include polymers other than the polymer (A) (hereinafter referred to as “other polymers”), compounds having at least one epoxy group in the molecule, Examples include functional silane compounds, photopolymerizable compounds, antioxidants, metal chelate compounds, curing accelerators, surfactants, fillers, dispersants, and photosensitizers. Examples of the other polymer include polyamic acid having no cyclobutene ring structure, imidized polymer of the polyamic acid, polyamic acid ester having no cyclobutene ring structure, polyester, cellulose derivative, polyacetal, polystyrene derivative, poly (Styrene-phenylmaleimide) derivatives, poly (meth) acrylates and the like. The blending ratio of these other components can be appropriately selected according to each compound as long as the effects of the present disclosure are not impaired.

The blending ratio of the polymer (A) is preferably 30 parts by weight or more, more preferably 40 parts by weight or more, with respect to 100 parts by weight of the total polymer components contained in the liquid crystal aligning agent. More preferably, it is 50 parts by weight or more. This is because when the proportion is less than 30 parts by weight, the film is not sufficiently cured and the effects of the present invention tend not to be sufficiently obtained.
<Solvent>
The liquid crystal aligning agent which concerns on this invention is prepared as a liquid composition formed by disperse | distributing or melt | dissolving a polymer (A) and the other component mix | blended as needed in an organic 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 (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, etc. It is in the range of 1 to 10% by weight. That is, the liquid crystal aligning agent is applied to the substrate surface as will be described later, and preferably heated to form a coating film that is a liquid crystal alignment film or a coating film that becomes a liquid crystal alignment film. At this time, when the solid content concentration is less than 1% by weight, the film thickness of the coating film becomes too small, and it becomes difficult to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, 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 range of the solid content concentration varies depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, when the spinner method is used, 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 in the range of 1.5 to 4.5% by weight. It is particularly preferred. 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 when preparing the liquid crystal aligning agent is preferably 10 to 50 ° C, more preferably 20 to 30 ° C.
[Liquid crystal alignment film and liquid crystal display element]
By using the liquid crystal aligning agent described above, the liquid crystal alignment film according to the present invention is manufactured. Moreover, the liquid crystal display element which concerns on 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 according to 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. Although it can be applied to various operation modes, it is particularly suitable for a PSA mode liquid crystal display element (liquid crystal element).

The manufacturing method of the said liquid crystal display element can be manufactured by the process including the following processes, for example.
A step of forming a coating film by applying the liquid crystal aligning agent of the present invention on the conductive film of a pair of substrates having a conductive film;
A step of constructing a liquid crystal cell by arranging a pair of substrates on which the coating film is formed facing each other so that the coating film faces through a liquid crystal layer,
Irradiating the liquid crystal cell with light while applying a voltage between the conductive films of the pair of substrates.
[First step: Formation of coating film]
Examples of the substrate include glass such as float glass and soda glass; and a transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly (alicyclic olefin). As the conductive film, it is preferable to use a transparent conductive film, for example, a NESA film (registered trademark of PPG, USA) made of tin oxide (SnO ₂ ) or indium oxide-tin oxide (In ₂ O ₃ —SnO ₂ ). An ITO film or the like can be used. This conductive film is preferably a patterned conductive film partitioned into a plurality of regions. With such a conductive film, when a voltage is applied between the conductive films, the direction of the pretilt angle of the liquid crystal molecules can be changed for each region by applying a different voltage in each region. The characteristics can be made wider.

  As a method of applying the liquid crystal aligning agent of the present invention on the formation surface of the transparent conductive film on the pair of substrates, it can be preferably performed by an offset printing method, a spin coating method, a roll coater method or an ink jet printing method. 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 functional titanium is formed on the surface of the substrate surface on which the coating film is to be formed. You may give the pretreatment which apply | coats a compound etc. previously.

  After applying the liquid crystal aligning agent to the substrate, 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 post-bake temperature 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. Thus, the film thickness of the formed film is preferably 0.001 to 1 μm, more preferably 0.005 to 0.5 μm.

  By removing the organic solvent by heating after applying the liquid crystal aligning agent, a coating film to be an alignment film is formed. 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.

The coating film thus formed may be used as it is in the following second step, or may be subjected to a second step after rubbing the coating surface as necessary. The rubbing treatment can be performed by rubbing the coating film surface in a certain direction with a roll wound with a cloth made of fibers such as nylon, rayon, and cotton.
[Second step: Construction of liquid crystal cell]
A liquid crystal cell is manufactured by preparing two substrates on which a liquid crystal alignment film is formed as described above, and disposing a liquid crystal layer containing a liquid crystal compound and a photopolymerizable compound between the two substrates arranged opposite to each other. To do. In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example. The first method is a conventionally known method (vacuum injection 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. After injecting and filling the liquid crystalline compound and the photopolymerizable compound into the cell gap partitioned by the above, a liquid crystal cell is manufactured by sealing the injection hole. The second method is a method called an ODF (One Drop Fill) method. For example, an ultraviolet light curable sealing material is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and liquid crystal properties are applied to predetermined locations on the liquid crystal alignment film surface. After dropping the mixture of the compound and photopolymerizable compound, the other substrate is bonded so that the liquid crystal alignment film faces, and the liquid crystal compound is spread over the entire surface of the substrate, and then the entire surface of the substrate is irradiated with ultraviolet light. Then, the liquid crystal cell is manufactured by curing the sealant.

  Regardless of which method is used, the liquid crystal cell produced as described above is further heated to a temperature at which the used liquid crystalline compound takes an isotropic phase, and then gradually cooled to room temperature, whereby the flow during liquid crystal filling is The orientation may be removed.

  As the sealing agent, for example, an epoxy resin containing a curing agent and aluminum oxide spheres as a spacer can be used.

  As the liquid crystalline compound, nematic liquid crystal having negative dielectric anisotropy can be preferably used. For example, dicyanobenzene liquid crystal, pyridazine liquid crystal, Schiff base liquid crystal, azoxy liquid crystal, biphenyl liquid crystal, phenyl cyclohexane liquid crystal, A terphenyl liquid crystal or the like can be used. In addition, as the liquid crystal compound, an alkenyl liquid crystal that is a monofunctional liquid crystal compound having one of an alkenyl group and a fluoroalkenyl group is used in that the response speed of the PSA mode liquid crystal display element can be further increased. It is preferable to use together. As such alkenyl type liquid crystal, conventionally known ones can be used, and examples thereof include compounds represented by the following formulas (L1-1) to (L1-9).

As the photopolymerizable compound, a compound having a functional group capable of radical polymerization such as an acryloyl group, a methacryloyl group, and a vinyl group can be used. From the viewpoint of reactivity, it is preferable to use a polyfunctional compound having an acryloyl group or a methacryloyl group. Further, from the viewpoint of stably maintaining the orientation of the liquid crystal molecules, the photopolymerizable compound is a compound having a total of two or more of at least one of a cyclohexane ring and a benzene ring as the liquid crystal skeleton. Is preferred. In addition, a conventionally well-known thing can be used as such a photopolymerizable compound. The blending ratio of the photopolymerizable compound is preferably 0.1 to 0.5% by weight with respect to the total amount of the liquid crystal compound to be used. Moreover, it is preferable that the thickness of a liquid-crystal layer shall be 1-5 micrometers.
[Third step: light irradiation step]
After the construction of the liquid crystal cell, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films of the pair of substrates. The voltage applied here can be, for example, 5 to 50 V direct current or alternating current. Moreover, as light to irradiate, the ultraviolet-ray and visible light which contain light with a wavelength of 150-800 nm can be used, for example, However, The ultraviolet-ray containing light with a wavelength of 300-400 nm is preferable. As a light source of irradiation light, for example, a low pressure mercury lamp, a high pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, or the like can be used. In addition, the ultraviolet rays in the above preferable wavelength region can be obtained by means of using a light source in combination with, for example, a filter diffraction grating. The irradiation dose of light, preferably less than 1,000 J / ^{m 2} or more 200,000 J / ^{m 2,} more preferably from 1,000~100,000J / ^{m 2.}

  And a PSA mode liquid crystal display element can be obtained by bonding a polarizing plate to the outer surface of the liquid crystal cell after light irradiation. As a polarizing plate used here, a polarizing plate composed of a polarizing film called an “H film” in which polyvinyl alcohol is stretched and oriented while absorbing iodine and sandwiched between cellulose acetate protective films or a polarizing film made of the H film itself. Can be mentioned.

  The liquid crystal element of the present disclosure can be effectively applied to various applications, for example, watches, portable games, word processors, notebook computers, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smartphones, various monitors. It can be used for various display devices such as liquid crystal televisions and information displays, and light control films. Moreover, the liquid crystal element formed using the liquid crystal aligning agent of this indication can also be applied to retardation film.

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

The weight average molecular weight of each polymer, the epoxy equivalent, the solution viscosity of each polymer solution, and the imidization ratio of polyimide in each synthesis example were measured by the following methods.
[Weight average molecular weight of polymer]
The weight average molecular weight Mw of the polymer is a polystyrene 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
[Epoxy equivalent]
The epoxy equivalent is a value measured according to the “hydrochloric acid-methyl ethyl ketone method” of JIS C2105.
[Solution viscosity of polymer solution]
The solution viscosity [mPa · s] of the polymer solution was measured at 25 ° C. using an E-type rotational viscometer for a solution prepared to a polymer concentration of 10% by weight using a predetermined solvent.
[Imidation rate of polyimide]
The polyimide solution was poured into pure water, and the resulting precipitate was sufficiently dried under reduced pressure at room temperature, then dissolved in deuterated dimethyl sulfoxide, and ¹ H-NMR was measured at room temperature using tetramethylsilane as a reference substance. From the obtained ¹ H-NMR spectrum, the imidization rate [%] was determined by the formula represented by the following formula (x).

Imidation rate [%] = (1-A ¹ / A ² × α) × 100 (x)
(In Formula (x), 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 polymer precursor (polyamic acid). The number ratio of other protons to one proton of NH group in)
<Synthesis of polymer>
[Synthesis Example P1: Polyimide synthesis of polymer (A1)]
220 g (1.0 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride, 150 g (0.3 mol) of 3- (2,4-diaminophenoxy) cholestane as diamine, 93 g (0.2 mol) of a compound represented by the formula DA-1-1 and 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-indene-5-amine 133 g (0.5 mol) was dissolved in 2,200 g of N-methyl-2-pyrrolidone (NMP) and reacted at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. The solution viscosity measured by taking a small amount of the obtained polyamic acid solution was about 1,450 mPa · s.

Next, 2,800 g of NMP was added to the obtained polyamic acid solution, 79 g of pyridine and 100 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring-closing reaction, the solvent in the system is replaced with new NMP (by this operation, pyridine and acetic anhydride used in the dehydration ring-closing reaction are removed from the system), and the polyimide as the polymer (A1) A solution containing about 15% by weight of (P-1) was obtained. The imidation ratio of the obtained polyimide (P-1) was about 51%.

(DA-1-1)
[Synthesis Example P2: Polyamic acid synthesis of polymer (A1)]
200 g (1.0 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 52 g (0.1 mol) of 3- (3,5-diaminobenzoyloxy) cholestane as diamine ), 128 g (0.2 mol) of the compound represented by the following formula DA-4-1 and 150 g (0.7 mol) of 2,2′-dimethyl-4,4′-diaminobiphenyl were converted to 3,100 g of NMP and γ— It melt | dissolved in the mixed solvent which consists of 760 g of butyrolactone, and the solution containing 10 weight% of polyamic acids (P-2) which is a polymer (A1) was obtained by reacting at 40 degreeC for 3 hours. The solution viscosity of this polyamic acid solution was 160 mPa · s.

(DA-4-1)
[Synthesis Example P3: Polyimide synthesis of other polymers]
220 g (1.0 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride, 74 g (0.15 mol) of 3- (2,4-diaminophenoxy) cholestane as diamine, 1 40 g (0.15 mol) of-(4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-indene-5-amine and 110 g of 3,5-diaminobenzoic acid (0.7 Mol) was dissolved in 1,800 g of NMP and reacted at 60 ° C. for 6 hours to obtain a solution containing polyamic acid. The solution viscosity measured by separating a small amount of the obtained polyamic acid solution was about 1,300 mPa · s.

Next, 2,200 g of NMP was added to the obtained polyamic acid solution, 120 g of pyridine and 150 g of acetic anhydride were added, and dehydration ring closure reaction was performed at 110 ° C. for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with new NMP to obtain a solution containing about 15% by weight of another polymer, polyimide (P-3). The imidation ratio of the obtained polyimide (P-3) was about 67%.
[Synthesis Example P4: Synthesis of Polyamic Acid of Other Polymer]
2,3,5-Tricarboxycyclopentylacetic acid dianhydride 220 g (1.0 mol) as tetracarboxylic dianhydride, 4- (2- (4- (4-pentylcyclohexyl) phenoxy) ethoxy) benzene- as diamine 79 g (0.2 mol) of 1,3-diamine, 40 g (0.2 mol) of 4,4′-diaminodiphenylmethane, and 91 g (0.6 mol) of 2,5-diaminobenzoic acid were added to 2,700 g of NMP and γ- By dissolving in 1,200 g of butyrolactone and reacting at 40 ° C. for 3 hours, a solution containing 10% by weight of polyamic acid (P-4) as another polymer was obtained. The solution viscosity of this polyamic acid solution was 160 mPa · s.
[Synthesis Example S1: Synthesis of polyorganosiloxane of polymer (A1)]
In a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel and a reflux condenser, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECETS) 197 g as a hydrolyzable silane compound and the following formula (S-1 -1) 151 g (ECETS: compound represented by the following formula (S-1-1) = 80: 20 (molar ratio)), 500 g of methyl isobutyl ketone as a solvent, and 10.0 g of triethylamine as a catalyst. Charged and mixed at room temperature. Next, 100 g of deionized water was dropped from the dropping funnel over 30 minutes, and then the reaction was performed at 80 ° C. for 6 hours under reflux with stirring. 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 hydrolyze having an epoxy group. The condensate was obtained as a viscous transparent liquid.

When this hydrolysis condensate was subjected to ¹ H-NMR analysis, a peak attributed to the epoxy group was obtained in the vicinity of chemical shift (δ) = 3.2 ppm according to the theoretical intensity. It was confirmed that no reaction occurred.

Subsequently, the obtained hydrolysis condensate was reacted with carboxylic acid. First, the hydrolysis condensate having an epoxy group obtained above was charged into a 200 mL three-necked flask, and 30.0 g of methyl isobutyl ketone as a solvent and 75.1 g of 4-octyloxybenzoic acid (OCTBA) as a carboxylic acid (as a raw material) 30 mol% with respect to the total of the hydrolyzable silane compounds used and 38 mol% with respect to the epoxy group of the hydrolysis condensate.) And 36.1 g of 11- (4-cyclohexylphenoxy) undecanoic acid (It corresponds to 10 mol% with respect to the total of the hydrolyzable silane compounds used as raw materials.) 0.10 g of UCAT 18X (trade name, manufactured by San Apro Co., Ltd., epoxy compound curing accelerator) is charged as a catalyst. The reaction was carried out with stirring at 100 ° C. for 48 hours. After completion of the reaction, the organic layer obtained by adding ethyl acetate to the reaction mixture was washed with water three times, dried using magnesium sulfate, and then the solvent was distilled off to obtain a polyorganosiloxane (A1) as a polymer (A1). 367.4 g of S-1) was obtained. About this polyorganosiloxane (S-1), the weight average molecular weight Mw in terms of polystyrene measured by gel permeation chromatography (GPC) was 8,000.
[Synthesis Examples S2 to S4, S6: Synthesis of polyorganosiloxane]
A polyorganosiloxane (S-2) which is a polymer (A1) is obtained by performing the same operation as in Synthesis Example S1 except that the types and amounts of the hydrolyzable silane compound and carboxylic acid are as shown in Table 1 below. ) To (S-3), (S-6) and polyorganosiloxane (S-4) as other polymers were obtained. The yield and Mw of these polyorganosiloxanes are shown in Table 1 below.

The abbreviations of the respective compounds in Table 1 have the following meanings.
(Hydrolyzable silane compound)
ECETS: 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane S-1-1: a compound represented by the following formula (S-1-1)

(S-1-1)
TEOS: Tetraethoxysilane ODES: Octadecyltriethoxysilane S-1-2: Compound represented by the following formula (S-1-2)

(S-1-2)
(carboxylic acid)
OCTBA: 4-octyloxybenzoic acid CPUA: 11- (4-cyclohexylphenoxy) undecanoic acid PCHBA: 4- (4-pentylcyclohexyl) benzoic acid C-1-1: represented by the following formula (C-1-1) Compound

(C-1-1)
C-1-2: Compound represented by the following formula (C-1-2)

(C-1-2)
SACY: Succinic acid = 5ξ-cholestan-3-yl PCCHUBA: 11- (4- (4′-pentylbi (cyclohexane) -4-yl) phenoxy) undecanoic acid (compound represented by the following formula (p1))
C-1-3: Compound represented by the following formula (C-1-3)

(C-1-3)

In addition, the “molar ratio” of the hydrolyzable silane compound in Table 1 indicates the use ratio of each silane compound with respect to the total of the hydrolyzable silane compounds used. The “molar ratio” of the carboxylic acid indicates the use ratio of each carboxylic acid relative to the total of the hydrolyzable silane compounds used. In Synthesis Examples S1 to S4 and S6, two types of carboxylic acids were used.
[Synthesis Example S5: Synthesis of polyorganosiloxane of polymer (A1)]
An ethanol solution of oxalic acid was prepared by adding 52.8 g of ethanol to a four-necked reaction flask equipped with a reflux tube and adding 20.0 g of oxalic acid to the ethanol in small portions while stirring. Next, the solution was heated to the reflux temperature, and 20.8 g of tetraethoxysilane, 4.2 g of octadecyltriethoxysilane and 54 g of the compound represented by the above formula (S-1-2) were added to the solution under reflux. The mixture was added dropwise. After completion of the dropwise addition, heating was continued under reflux for 5 hours, followed by cooling and adding 75 g of butyl cellosolve to prepare a solution containing polyorganosiloxane (S-5) having a SiO ₂ concentration of 4% by weight. When this solution was analyzed by gas chromatography, no alkoxysilane monomer was detected.
<Preparation of liquid crystal composition>
[Preparation of Liquid Crystal Composition LC1]
5% by weight of a liquid crystalline compound represented by the above formula (L1-1) and a photopolymerizable compound represented by the following formula (L2-1) with respect to 10 g of nematic liquid crystal (MLC-6608, manufactured by Merck & Co., Inc.) Was added and mixed to obtain a liquid crystal composition LC1.

[Preparation of Liquid Crystal Composition LC2]
A liquid crystal composition LC2 was prepared in the same manner as the liquid crystal composition LC1 except that the amount of the liquid crystal compound represented by the formula (L1-1) was changed from 5 wt% to 10 wt%.
<Example 1>
[Preparation of liquid crystal aligning agent]
In the solution containing the polyimide (P-1) and the solution containing the polyamic acid (P-2), the respective solid weights are polyimide (P-1): polyamic acid (P-2) = 20: 80. NMP and butyl cellosolve (BC) were added as an organic solvent to the mixed solution to obtain a solution having a solvent composition of NMP: BC = 50: 50 (weight ratio) and a solid concentration of 6.0% by weight. A liquid crystal aligning agent was prepared by filtering this solution using a filter having a pore size of 1 μm.
[Manufacture of liquid crystal cells]
Using the liquid crystal aligning agent prepared above, the presence or absence of the pattern of the transparent electrode and the amount of ultraviolet irradiation (2 levels) were changed to produce a total of four liquid crystal cells. In addition, various characteristics of the manufactured liquid crystal cells were evaluated.
[Production of liquid crystal cell having transparent electrode without pattern]
The liquid crystal aligning agent prepared above was applied onto the transparent electrode surface of a glass substrate having a transparent electrode made of an ITO film using a liquid crystal alignment film printer (Nissha Printing Co., Ltd.), and a hot plate at 80 ° C. After removing the solvent by heating (prebaking) for 1 minute above, it was heated (postbaked) for 10 minutes on a hot plate at 150 ° C. to form a coating film having an average film thickness of 600 mm.

  The coating film was rubbed with a rubbing machine having a roll wrapped with a rayon cloth at a roll rotation speed of 400 rpm, a stage moving speed of 3 cm / sec, and a hair foot indentation length of 0.1 mm. 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. This operation was repeated to obtain a pair (two) of substrates having a liquid crystal alignment film. This rubbing process is a weak rubbing process performed for the purpose of controlling the tilting of the liquid crystal and performing alignment division by a simple method.

  Next, after applying an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 3.5 μm to the outer edge of the surface having the liquid crystal alignment film for one of the pair of substrates, the liquid crystal alignment film surface is placed on the pair of substrates. The adhesives were cured by overlapping and pressing so as to face each other. Next, the liquid crystal composition LC1 prepared above was filled between the pair of substrates from the liquid crystal inlet, and then the liquid crystal inlet was sealed with an acrylic photo-curing adhesive to produce a liquid crystal cell.

The above operation was repeated to produce two liquid crystal cells having a patternless transparent electrode. One of them was used for the evaluation of the voltage holding ratio as it was. For the remaining one liquid crystal cell, an alternating current of 10 Hz is applied between the conductive films and the liquid crystal is driven, and an ultraviolet irradiation device using a metal halide lamp as the light source is used. It was irradiated with ultraviolet rays at dose of m ^2. In addition, this irradiation amount is the value measured using the light meter measured on the basis of wavelength 365nm.
[Evaluation of voltage holding ratio]
For each liquid crystal cell manufactured 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 then the voltage holding ratio (VHR) after 167 milliseconds from the application release was measured. . The measurement results are shown in Table 2 below. In addition, as a measuring apparatus, Toyo Technica Co., Ltd. make and VHR-1 were used.
[Manufacture of Liquid Crystal Cell Having Patterned Transparent Electrode]
The liquid crystal aligning agent of Example 1 prepared above was patterned into a slit shape as shown in FIG. 1, and liquid crystal was formed on each electrode surface of two glass substrates each having an ITO electrode partitioned into a plurality of regions. It is applied using an alignment film printer (Nissha Printing Co., Ltd.), heated on a hot plate at 80 ° C. for 1 minute (prebaked) to remove the solvent, and then heated on a hot plate at 150 ° C. for 10 minutes. (Post-baking) to form a coating film having an average film thickness of 600 mm. The coating film was subjected to ultrasonic cleaning for 1 minute in ultrapure water and then dried in a clean oven at 100 ° C. for 10 minutes to obtain a substrate having a liquid crystal alignment film. This operation was repeated to obtain a pair (two) of substrates having a liquid crystal alignment film. The used electrode pattern is the same type as the electrode pattern in the PSA mode.

  Next, after applying an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 5.5 μm to the outer edges of the pair of substrates having the liquid crystal alignment film, the liquid crystal alignment film surfaces are overlapped and pressure-bonded so as to face each other. The adhesive was cured. Next, the liquid crystal composition LC1 prepared above was filled between the pair of substrates from the liquid crystal inlet, and then the liquid crystal inlet was sealed with an acrylic photo-curing adhesive to produce a liquid crystal cell.

The above operation was repeated to produce a total of two liquid crystal cells having patterned transparent electrodes. One of them was used for the evaluation of AC afterimage characteristics described later. With respect to the remaining one liquid crystal cell, at a dose of 100,000 J / m ² with a voltage applied between the conductive films in the same manner as in the case of manufacturing a liquid crystal display element having a transparent electrode without pattern. After light irradiation, it was subjected to evaluation of AC afterimage characteristics.
[Evaluation of AC afterimage characteristics (evaluation of pretilt angle stability)]
The liquid crystal cells produced above are described in “T. J. Scheffer et. Al., J. Appl. Phys. Vol 48, p1783 (1977)” and “F. Nakano, et. Al., JPN. J. Appl. Phys. Vol.19, p2013 (1980) "and measured by a rotating crystal method using He-Ne laser light. The measurement was performed with respect to a pretilt angle (initial pretilt angle θini) before voltage application to the liquid crystal cell, and a pretilt angle after driving for 13 hours at AC 9 V at room temperature (pretilt angle θac after driving). Further, the pretilt angle change rate β [%] was calculated by the following formula (y). The case where the pretilt angle change rate β was less than 3% was evaluated as “good”, the case where it was 3% or more and less than 5% was evaluated as “bad” when it was “good” or 5% or more. The results are shown in Table 2 below.

    Pretilt angle change rate β [%] = (θac−θini) / θini × 100 (y)

The “parts by weight” in Table 2 above indicates the blending amount of each component relative to 100 parts by weight of the total amount of the liquid crystal aligning agent.
<Examples 2 to 9, 11, 12 and Comparative Examples 1 and 2>
A liquid crystal aligning agent was prepared in the same manner as in Example 1 except that the type and amount of the polymer used for preparing the liquid crystal aligning agent were changed as shown in Table 2 above. In addition, about polyorganosiloxane (S-1)-(S-4), (S-6), after melt | dissolving in NMP, it used for preparation of the liquid crystal aligning agent. For polyorganosiloxane (S-5), the reaction solution was poured into a large excess of methanol to precipitate the reaction product, which was washed with methanol and then dried at 40 ° C. under reduced pressure for 15 hours. The powder obtained by the above was dissolved in NMP and used for the preparation of a liquid crystal aligning agent. Moreover, while using each of these liquid crystal aligning agents, the liquid crystal cell was manufactured similarly to Example 1, and the manufactured liquid crystal cell was evaluated. In Examples 6 and 12 and Comparative Example 1, the liquid crystal composition used in manufacturing the liquid crystal cell was changed from LC1 to LC2. The evaluation results are shown in Table 2 above.
[Evaluation of high-speed response]
<Example 6A>
Using the liquid crystal cell having the non-patterned transparent electrode produced in Example 6, the high-speed response of the liquid crystal molecules was evaluated. The liquid crystal cell manufactured above is sandwiched between two polarizing plates arranged in a crossed Nicol state. First, a visible light lamp is irradiated without applying a voltage, and the brightness of the light transmitted through the liquid crystal cell is measured. Measured with a multimeter, this value was taken as 0% relative transmittance. Next, the transmittance when AC 5 V was applied for 5 seconds between the electrodes of the liquid crystal cell was measured in the same manner as described above, and this value was defined as a relative transmittance of 100%. When AC 5 V was applied to each liquid crystal cell, the time until the relative transmittance shifted from 10% to 90% was measured, and this time was defined as the response speed. When the response speed was less than 5 msec, the high-speed response was “good”, and when it was 5 msec or more, the high-speed response was “good”. As a result, the high-speed response of the liquid crystal cell of Example 6 was “good”.
<Example 12A and Comparative Example 1A>
The response speed of the liquid crystal molecules was evaluated in the same manner as in Example 6A, except that the liquid crystal cell used was changed to that of Example 12 and Comparative Example 1. The results are shown in Table 3 below.

<Example 10>
[Preparation of liquid crystal aligning agent]
After dissolving the polyorganosiloxane (S-1) obtained in Synthesis Example S1 in NMP, this polyorganosiloxane-containing solution and the polyimide (P-3) as the other polymer obtained in Synthesis Example P3 are used. The contained solution was mixed so that the weight of each solid content was polyimide (P-3): polyorganosiloxane (S-1) = 90: 5. Next, after adding NMP and BC, N, N, N ′, N′-tetraglycidyl-4,4′-diaminodiphenylmethane was added in the same amount (by weight) as polyorganosiloxane (S-1), and the solvent composition was It was set as the solution of NMP: BC = 50: 50 (weight ratio) and the solid content concentration of 6.0 weight%. A liquid crystal aligning agent was prepared by filtering this solution using a filter having a pore size of 1 μm. Moreover, the liquid crystal cell was manufactured similarly to Example 1 except the point which changed the liquid crystal aligning agent to be used, and the evaluation was performed. The evaluation results are also shown in Table 2 above.

  In Comparative Examples 1 and 2, the decrease in the voltage holding ratio and the decrease in the AC afterimage characteristics due to ultraviolet irradiation appeared significantly. On the other hand, in Examples 1 to 12, a high voltage holding ratio was maintained even after ultraviolet irradiation, and the AC afterimage characteristics were also good. Among them, in Examples 3, 6, 7, 9, 11, and 12 using a liquid crystal aligning agent containing at least one of polyamic acid and polyimide as a polymer and polyorganosiloxane (A1), AC afterimage characteristics are particularly good. there were. From these results, when an alkenyl-based liquid crystal is used in the PSA mode to achieve high-speed response of the liquid crystal panel, a voltage due to ultraviolet irradiation is obtained by forming a liquid crystal alignment film with a liquid crystal aligning agent containing the polymer (A1). It was found that a decrease in retention rate can be suppressed and AC afterimage characteristics can be improved. In addition, from the results of Examples 6A and 12A, it was found that a liquid crystal display element with high high-speed response can be obtained.

  Furthermore, except that the ITO electrode pattern on the glass substrate was changed to a fishbone electrode pattern as shown in FIG. 2 and FIG. A liquid crystal cell was manufactured and evaluated in the same manner as described above. Also in this case, the same effects as in Examples 1 to 12 were exhibited.

DESCRIPTION OF SYMBOLS 1 ... ITO electrode, 2 ... Slit part, 3 ... Light-shielding film

Claims (7)

A polysiloxane having at least one partial structure selected from the group represented by the following formula (1) and the following formulas (2) to (9), and
Selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, and selected from the group represented by the following formula (1-1), the following formula (1-2), and the following formulas (2) to (9). A polymer having at least one partial structure,
A liquid crystal aligning agent containing at least one polymer selected from the group consisting of:
(In the formulas (1) to (9),
X represents each independently a halogen atom, a hydroxyl group, a cyano group, a nitro group, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms,
a is an integer of 0 to 4, b is an integer of 0 to 3, c is an integer of 0 to 5,
R ₁ , R ₂ , R ₄ , R ₅ , R ₆ , R ₇ and R ₈ each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, or 1 to 20 carbon atoms. R ₁ represents an alkoxy group, an aryl group having 6 to 30 carbon atoms, an arylalkyl group having 7 to 30 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and an alkenyloxy group having 2 to 12 carbon atoms, R ₁ And R ₂ may be linked to form a 3- to 6-membered cyclic alkane or heterocyclic group, and an alkyl group, alkoxy group, aryl group, arylalkyl group, alkenyl group, alkenyloxy group, cyclic alkyl group, The heterocyclic group may have a substituent,
R ₃ represents a hydroxyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or any group represented by the following formula (10), and the alkoxy group may have a substituent,

(In Formula (10), Y ₂ is a methylene group, —NR, an oxygen atom, or a sulfur atom, R is independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X and c are the above Is the same.)
* Represents a bond. )

(In Formula (1-1) and (Formula 1-2),
X, a, R ₁ , R ₂ , R ₃ , * are the same as above,
d is an integer of 1 to 5,
R ₉ and R ₁₀ are each independently a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 30 carbon atoms, or a carbon atom. Represents an arylalkyl group having 7 to 30 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, and an alkenyloxy group having 2 to 12 carbon atoms, and R ₁ and R ₂ are linked to form a 3- to 6-membered cyclic alkane or A heterocyclic group may be formed, and an alkyl group, an alkoxy group, an aryl group, an arylalkyl group, an alkenyl group, an alkenyloxy group, a cyclic alkyl group, and a heterocyclic group may have a substituent,
At least one selected from the group of R ₉ and R ₁₀ represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkenyl group having 2 to 12 carbon atoms, or an alkenyloxy group having 2 to 12 carbon atoms. ) A polysiloxane having at least one partial structure selected from the group represented by formula (1), formula (3), formula (4) and formula (5), and
It is selected from the group consisting of polyamic acid, polyamic acid ester, polyimide and polyamide, and is represented by the formula (1-1), formula (1-2), formula (3), formula (4) and formula (5). A polymer having at least one partial structure selected from the group consisting of:
The liquid crystal aligning agent of Claim 1 containing the at least 1 sort (s) of polymer chosen from the group which consists of. A step of applying a liquid crystal aligning agent according to any one of claims 1 and 2 to form a coating film on the conductive film of a pair of substrates having a conductive film;
A step of constructing a liquid crystal cell by arranging the pair of substrates on which the coating film is formed so as to face each other with the coating film facing each other through a liquid crystal layer;
Irradiating the liquid crystal cell with light while applying a voltage between the conductive films of the pair of substrates.   The liquid crystal aligning film formed using the liquid crystal aligning agent as described in any one of Claims 1-2.   A liquid crystal device comprising the liquid crystal alignment film according to claim 4.   A polysiloxane having at least one partial structure selected from the group represented by the formula (1) and the formulas (2) to (9). Selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, and selected from the group represented by the formula (1-1), the formula (1-2), and the formulas (2) to (9). A polymer having at least one partial structure.