TWI555777B - Liquid crystal alignment agent for photo-alignment, liquid crystal alignment film and manufacturing method thereof, liquid crystal display device, compound and polymer - Google Patents

Description

Liquid alignment agent for liquid alignment, liquid crystal alignment film, and method for producing the same, Liquid crystal display elements, compounds, and polymers

The present invention relates to a method for producing a liquid crystal alignment film, a liquid crystal alignment agent for photoalignment, a liquid crystal display device, a compound, and a polymer, and more particularly to a technique for forming a liquid crystal alignment film of a liquid crystal display device of a transverse electric field type by a photo-alignment method.

Conventionally, as the liquid crystal display element, various driving methods have been developed in which the electrode structure or the physical properties of the liquid crystal molecules to be used are different. For example, a twisted nematic (TN) type or a super twisted nematic (Super Twisted Nematic) is known. Longitudinal electric field type liquid crystal display elements such as Vertical Alignment (VA) type, or transverse electric field mode such as In-Plane Switching (IPS) and Fringe Field Switching (FFS) Various liquid crystal display elements such as liquid crystal display elements. Longitudinal electric field type liquid crystal display element The liquid crystal display element of the transverse electric field type is configured such that the electrodes are formed on the pair of substrates arranged in the opposite direction and the electric field is generated in the direction perpendicular to the substrate. An electrode is formed on one of the pair of substrates, and an electric field is generated in a direction parallel to the substrate. Thus, it is known that the lateral electric field type liquid crystal display element has a wide viewing angle characteristic and can perform high quality display as compared with the prior longitudinal electric field mode.

The liquid crystal display element controls the alignment state of the liquid crystal molecules by the liquid crystal alignment film formed on the substrate. As a material of the liquid crystal alignment film, polyacrylic acid or polyimide is usually used from the viewpoint of various properties such as heat resistance, mechanical strength, and affinity with liquid crystal. In addition, as a method of imparting a liquid crystal alignment ability to a coating film formed of a liquid crystal alignment agent containing a polyphthalic acid or the like, in recent years, a photoalignment method using photoisomerization, photodimerization, photodecomposition, or the like has been proposed as A technique that replaces the friction method. This photoalignment method is a method of controlling the alignment of liquid crystal molecules by irradiating polarized or non-polarized radiation to a radiation-sensitive organic thin film formed on a substrate to impart anisotropy to the film. According to this method, generation of dust or static electricity in the step can be suppressed as compared with the conventional rubbing method, and thus occurrence of display failure or deterioration in yield due to dust or the like can be suppressed. In addition, it also has an advantage that the liquid crystal alignment ability can be uniformly imparted to the organic thin film formed on the substrate.

Various liquid crystal alignment agents have been proposed as a liquid crystal alignment agent used for forming a liquid crystal alignment film of a liquid crystal display device by a photo-alignment method (see, for example, Patent Document 1 to Patent Document 4). In Patent Document 1, a liquid crystal alignment agent containing a polymer having a group having a chalcone structure in a side chain is subjected to a liquid crystal alignment agent. It is disclosed in Patent Document 2 that a liquid crystal alignment agent containing a polymer having a flavonoid structure is disclosed. Further, in Patent Document 3, a liquid crystal alignment agent containing a polymer having an azobenzene structure or an anthracene structure is disclosed, and in Patent Document 4, an azo compound containing a low molecular weight is used. Liquid crystal alignment agents have been disclosed.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2003-307736

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2004-163646

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2002-250924

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2004-83810

Although the optical alignment method has the above-described advantages, in the liquid crystal display device using the transverse electric field method using the photoalignment method, burn-in may become a problem, and improvement is desired. Further, when the liquid crystal alignment ability is imparted to the coating film by the photo-alignment method, the coating film is required to have good sensitivity to light.

Further, in the case of a photo-alignment method in which a chemical change occurs by irradiation with ultraviolet rays or the like, there is a tendency that electrical characteristics are generally poor as compared with the liquid crystal alignment film which has been subjected to the rubbing treatment in the prior art, especially in the photodecomposition accompanying the polymer. In the case of the liquid crystal cell, there is a problem that the impurity ions increase and the voltage holding ratio is liable to decrease. On the other hand, with the recent increase in quality of liquid crystal panels, it is required to display a high voltage holding ratio in a liquid crystal display element.

The present invention has been made in view of the above problems, and a main object thereof is to provide a method for producing a liquid crystal alignment film which can exhibit good liquid crystal alignment by light irradiation with a coating film and can be obtained by burning. A liquid crystal display element with few high voltage holding ratios is attached.

The inventors of the present invention have diligently studied in order to achieve the above-described problems of the prior art, and have focused on a photo-Fries rearrangement as a mechanism for causing anisotropicity of a film by light irradiation. . The light Freyce rearrangement reaction is a reaction that produces a skeleton change of a molecular structure by a rearrangement reaction of a phenyl ester to an aromatic hydroxyketone. Further, the inventors of the present invention have found that at least one of polyamic acid, polyphthalate, and polyimine having a phenyl ester structure in the main chain is used and a liquid crystal alignment film is formed by photo-alignment method. As a result, the problem can be solved, and the present invention has been completed. Specifically, the present invention provides the following methods for producing a liquid crystal alignment film, a liquid alignment agent for photoalignment, a liquid crystal display device, a compound, and a polymer.

In one aspect, the present invention provides a method for producing a liquid crystal alignment film, comprising: a film forming step of applying a photo-alignment liquid crystal alignment agent containing a polymer (C) onto a substrate to form a coating film, the polymerization The substance (C) is at least one selected from the group consisting of polylysine, polyphthalate, and polyimine, and has a structure represented by the following formula (1) in the main chain (Y) And a light irradiation step of irradiating the coating film with light to form a liquid crystal alignment film.

(In the formula (1), X ¹ is a sulfur atom or an oxygen atom. "*" represents a bonding bond, respectively, wherein at least one of the two "*"s is bonded to the aromatic ring.)

Since the coating film formed by the liquid alignment alignment agent containing the polymer (C) has a good sensitivity to light, according to the method for producing a liquid crystal alignment film of the present invention, it is possible to obtain a good liquid crystal alignment by light irradiation. Liquid crystal alignment film. Further, a liquid crystal display element having less burnt and exhibiting a high voltage holding ratio can be obtained.

In another aspect, the present invention provides a liquid alignment agent for photoalignment characterized by comprising a polymer (C) selected from the group consisting of polylysine, polyphthalate, and poly At least one of the group consisting of ruthenium and having a structure (Y) represented by the formula (1) in the main chain. Further, in another aspect, a liquid crystal display element comprising a liquid crystal alignment film formed using the above-described production method is provided.

In another aspect, the present invention provides a compound represented by the following formula (2). Further, a polymer obtained by reacting at least one or two or more kinds of tetracarboxylic dianhydrides containing the compound with a diamine is provided.

(In the formula (2), R ²⁰ is a fluorine atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms or a fluoroalkyl group having 1 to 3 carbon atoms, and m is 0 to 4 An integer of n is 1 or 2. wherein, when a plurality of R ²⁰ are present in the molecule, the plurality of R ²⁰ are each independently and have the definition.)

Hereinafter, a method for producing a liquid crystal alignment film of the present invention will be described, and a photo-alignment liquid crystal alignment agent of the present invention used in the production method will be described. First, each component of the liquid alignment liquid crystal alignment agent (hereinafter also referred to as "photoalignment agent") and other components arbitrarily arbitrarily prepared will be described.

<polymer composition>

The photo-aligning agent of the present invention contains, as a polymer component, at least one of polyamine, polyglycolate, and polyimine obtained by reacting tetracarboxylic dianhydride with a diamine. Further, in particular, the polymer (C) having a structure (Y) represented by the following formula (1) in the main chain is polymerized as at least one of polyamine, polyglycolate and polyimine. Things.

(In the formula (1), X ¹ is a sulfur atom or an oxygen atom. "*" represents a bonding bond, respectively, wherein at least one of the two "*"s is bonded to the aromatic ring.)

Examples of the aromatic ring to which the "*" in the formula (1) is bonded include a benzene ring, a naphthalene ring, an anthracene ring and the like. Among these aromatic rings, a benzene ring is preferred from the viewpoint of liquid crystal alignment and transparency. From the viewpoint of sensitivity to light, X ¹ is preferably a sulfur atom, and from the viewpoint of easy availability and a wide selection of monomers which can be used, X ¹ is preferably an oxygen atom. Hereinafter, polyphthalic acid, polyphthalate, and polyimine having the above structure (Y) will be described in order.

<Polymer (C); Polylysine>

The synthesis of poly-proline (hereinafter also referred to as "poly-proline (C)") of the polymer (C) in the present invention includes, for example, the following method: [i] including the structure ( One or two or more kinds of tetracarboxylic dianhydrides of tetracarboxylic dianhydride (hereinafter also referred to as specific tetracarboxylic dianhydride) of Y) and a diamine having no structure (Y) And [ii] one or more selected from the group consisting of a tetracarboxylic dianhydride having the structure (Y) and a diamine (hereinafter, also referred to as a specific diamine) having the above structure (Y) a method in which a diamine is reacted; [iii] one or two or more kinds of tetracarboxylic dianhydrides containing a specific tetracarboxylic dianhydride are reacted with one or two or more kinds of diamines containing a specific diamine Methods.

[Specific tetracarboxylic dianhydride]

The specific tetracarboxylic dianhydride is a compound having a group represented by the above formula (1) and two acid anhydride groups (-CO-O-CO-), and specifically, it is represented by the following formula (a).

(In the formula (a), X ¹ is a sulfur atom or an oxygen atom. R ¹ and R ² each independently represent a monovalent organic group having one acid anhydride group, and at least one of R ¹ and R ² has an aromatic ring. The bonding bond of at least one side of "-CO-X ¹ -" is bonded to the aromatic ring.)

Examples of the monovalent organic group of R ¹ and R ² in the formula (a) include a group in which a hydrocarbon group having a carbon number of 1 to 40 is bonded to an acid anhydride group, and a hydrogen atom of the hydrocarbon group is derived from a halogen atom. The isosubstituted group contains "-O-", "-S-", "-CO-", "-CO-O-", "-CO-S-", and the carbon-carbon bond of the hydrocarbon group. A group obtained by bonding an acid anhydride group such as "-SO ₂ -", "-N=N-", "-NH-", or "-CO-NH-".

Here, the "hydrocarbon group" in the present specification may be a saturated hydrocarbon group or an unsaturated hydrocarbon group, and is a meaning including a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. In addition, the "chain hydrocarbon group" means a linear hydrocarbon group and a branched hydrocarbon group which do not contain a cyclic structure and contain only a chain structure. The "alicyclic hydrocarbon group" means a hydrocarbon group having a structure containing only an alicyclic hydrocarbon as a ring structure and not containing an aromatic ring structure. However, it is not necessary to include a structure containing only an alicyclic hydrocarbon, and a structure having a chain structure in a part thereof. The "aromatic hydrocarbon group" means a hydrocarbon group containing an aromatic ring structure as a ring structure. However, it is not necessary to include only the aromatic ring structure, and a structure of a chain structure or an alicyclic hydrocarbon may be contained in a part thereof.

The acid anhydride group of R ¹ and R ² is preferably bonded to an aromatic ring, and the aromatic ring is more preferably a benzene ring or a naphthalene ring. Specifically, R ¹ and R ² preferably have any one of the groups represented by the following formulas (a1-1) to (a1-3).

(wherein "*" represents a bond bond to a carbonyl group, an oxygen atom of "-O-C(=O)-" or a sulfur atom of "-S-C(=O)-".)

In the above, from the viewpoint of the liquid crystal alignment property, R ¹ and R ² more preferably have a group represented by the following formula (a1-1) or formula (a1-3), and particularly preferably have the formula The base represented by (a1-1). Further, the bond bond in each of the following formulae (a1-1) to (a1-3) is preferably bonded to a carbonyl group.

When one of R ¹ and R ² is a group represented by any one of the formulae (a1-1) to (a1-3), the other formula may be exemplified by the following formula (a2) ) the base represented.

(In the formula (a2), Ar ¹ is a benzene ring or a naphthalene ring, and X ² is -O-CO-* ¹ , -S-CO-* ¹ , -NH-CO-* ¹ , -O-, -CO- O-* ¹ , -CO-S-* ¹ or -CO- (where "* ¹ " represents a bonding bond bonded to Ar ¹ ). R ³ and R ⁷ are each independently substituted or unsubstituted Extending a cyclohexyl group, stretching a phenyl group or stretching a biphenyl group. In the case where n1=n3=1, R ⁶ is a divalent chain hydrocarbon group having a carbon number of 1 to 20, and a carbon-carbon group at the chain hydrocarbon group. A divalent group containing "-O-" between the bonds, -O-, -S-, -CO-, -CO-O-, -CO-S-, -SO ₂ -, -N=N-, - NH- or -CO-NH-, in the case where n1=n3=1, R ⁶ is a divalent chain hydrocarbon group having 1 to 20 carbon atoms or contains a carbon-carbon bond between the chain hydrocarbon groups. -O- "divalent group .n1, n2, n3 and m1 are independently 0 or 1." * "indicates a bond X ¹ bonds.)

From the viewpoint of liquid crystal alignment and transparency, Ar ^{1 of} the formula (a2) is preferably a benzene ring. From the viewpoint of the sensitivity to light, X ² is preferably -O-CO-* ¹ , -S-CO-* ¹ , -CO-O-* ¹ or -CO-S-* ¹ , more preferably -O- CO-* ¹ or -S-CO-* ¹ , and further preferably -S-CO-* ¹ .

From the viewpoint of making the sensitivity to light more favorable, R ³ and R ^{7 are} preferably a phenyl group or a biphenyl group. In addition, when R ³ and R ⁷ have a substituent, examples of the substituent include a fluorine atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, and a carbon number of 1. ~3 fluoroalkyl and the like. With respect to R ³ , the position of the substituent may be any of an ortho, meta or para position with respect to X ² , and with respect to R ⁷ , the position of the substituent may be an ortho, meta or para position with respect to X ¹ . One. However, when "-CO-O-" or "-CO-S-" is bonded to the benzene ring, the substituent is preferably ortho to the viewpoint of the sensitivity of light becoming high.

Furthermore, the reason why the coating film containing the polymer (C) exhibits liquid crystal alignment ability by light irradiation is not clear, and it is unclear whether it depends mainly on the light Fress rearrangement reaction or on the basis "-CO-X ¹ - The light decomposition, or depends on the two. Therefore, when "-CO-O-" or "-CO-S-" is bonded to the benzene ring, the substituent is introduced to the ortho position relative to the group, and the reason why the sensitivity becomes high is not clear, but It is presumed that if the generation of photodecomposition is dominant, it is difficult to rearrange due to introduction of a substituent, and as a result, photolysis is promoted.

Preferably, at least one of n1 and n3 is 1, more preferably n1=n3=1.

In view of the fact that the sensitivity to light is high, R ⁶ is preferably a divalent chain hydrocarbon group having 1 to 20 carbon atoms or a divalent group containing "-O-" between carbon-carbon bonds of the chain hydrocarbon group. The group represented by the following formula (3) is more preferable.

(In the formula (3), k and m are each independently 0 or 1, and l is an integer of 2 to 5, and n is an integer of 1 to 4. "*" represents a bonding key, respectively.)

From the viewpoint of appropriately performing the development of the anisotropy by light irradiation, m1 is preferably 1. Further, by using n2 in the formula (a2) and tetracarboxylic dianhydride having m1 as 1, a polylysine (C) having a structure represented by the formula (3) in the main chain can be obtained. .

Preferable specific examples of the group represented by the formula (a2) include a group represented by each of the following formulas (a2-1) to (a2-39).

(wherein, "*" indicates a bond key bonded to X ¹ .)

As the group represented by the formula (a2), among these, From the viewpoint of the sensitivity of light or the effect of reducing the burn-up, it is preferable to have the following formula (a2-3), formula (a2-4), formula (a2-6), formula (a2-7), and formula (a2). -9), a group represented by each of the formulae (a2-10), (a2-15), (a2-16), and (a2-30) to (a2-40), particularly preferably The groups represented by the formulae (a2-3), (a2-4), (a2-6), (a2-7), and (a2-30) to (a2-34).

Preferable specific examples of the specific tetracarboxylic dianhydride include compounds represented by the following formulas (a-1) to (a-15). Further, the following formula (a-3) and formula (a-4) correspond to the compound represented by the above formula (2). The specific tetracarboxylic dianhydride may be used alone or in combination of two or more.

The specific tetracarboxylic dianhydride in the present invention can be produced by suitably combining a conventional method of organic chemistry. For example, the tetracarboxylic dianhydride represented by the above formula (2) can be obtained by reacting trimellitic trichloride with a corresponding dithiol compound in a suitable organic solvent. Further, in the tetracarboxylic dianhydride represented by the above formula (2), as the substituent represented by R ²⁰ , a substituent which the R ³ and R ^{7 of} the formula (a2) may have may be used. instruction of. As the specific tetracarboxylic dianhydride, a compound obtained by introducing R ²⁰ as a substituent onto the benzene ring of the compound represented by the above formula (2) can also be preferably used.

[Other tetracarboxylic dianhydride]

In the case of the methods of [i] and [iii], as the tetracarboxylic dianhydride for the synthesis of polyglycine, only a specific tetracarboxylic dianhydride may be used, or a specific tetracarboxylic acid may be used. The acid dianhydride is used in combination with a tetracarboxylic dianhydride having no such structure (Y). As the tetracarboxylic dianhydride (also referred to as "other tetracarboxylic dianhydride") having no such structure (Y) which can be used in the methods of the above [i] to [iii], for example, aliphatic Tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride, and the like.

Specific examples of the tetracarboxylic dianhydride include, as the aliphatic tetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, and the like; as the alicyclic tetracarboxylic dianhydride, For example, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro- 5-(tetrahydro-2,5-dioxo-3-furanyl)-naphthoquinone [1,2-c]furan-1,3-dione, 1,3,3a,4,5,9b- Hexahydro-8-methyl-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphthoquinone [1,2-c]furan-1,3-dione, 3-oxa Bicyclo[3.2.1]octane-2,4-dione-6-spiro-3'-(tetrahydrofuran-2',5'-dione), 5-(2,5-dioxotetrahydro-3 -furyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2:3,5:6- Dihydride, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, 4,9-dioxatricyclo[5.3.1.0 ^2,6 ] The undecane-3,5,8,10-tetraketone, cyclohexanetetracarboxylic dianhydride, and the like; examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride and the like; The tetracarboxylic dianhydride or the like described in JP-A-2010-97188 is used. In addition, the other tetracarboxylic dianhydride may be used alone or in combination of two or more.

In the methods of [i] and [iii], the specific tetracarboxylic acid is used in comparison with the total amount of the tetracarboxylic dianhydride used for the synthesis of polyglycine, from the viewpoint of sufficiently obtaining the effects of the present invention. The use ratio of the dianhydride is preferably 30 mol% or more, more preferably 40 mol% or more, and still more preferably 50 mol% or more.

[specific diamine]

The specific diamine is a compound having a group represented by the above formula (1) and two primary amino groups, and is represented, for example, by the following formula (b).

(In the formula (b), X ¹ is a sulfur atom or an oxygen atom. R ⁴ and R ⁵ are each independently a divalent organic group, and at least one of R ⁴ and R ⁵ has an aromatic ring. "-CO-X ¹ The bond bond on at least one of the -" bonds to the aromatic ring.)

Examples of the divalent organic group of R ⁴ and R ⁵ in the formula (b) include a hydrocarbon group having 1 to 30 carbon atoms, a hydrogen atom of the hydrocarbon group substituted with a halogen atom or the like, and a hydrocarbon group. The carbon-carbon bond contains "-O-", "-S-", "-CO-", "-CO-O-", "-CO-S-", "-N=N-", etc. Base. Specific examples of the group "-R ⁴ -NH ₂ " and the group "-R ⁵ -NH ₂ " include a group represented by the following formula (b2). Further, the radical "-R ⁴ -NH ₂ " and the radical "-R ⁵ -NH ₂ " may be the same or different.

(In the formula (b2), A ¹ is a phenyl group, a biphenyl group or a cyclohexylene group, and X ⁴ is -O-CO-* ³ , -S-CO-* ³ , -O-, -CO-O -* ³ , -CO-S-* ³ , -CO-, -N=N-, -C=C- or -C≡C- (where "* ³ " represents the bond key bonded to A ¹ R ⁸ and R ¹⁰ are each independently a substituted or unsubstituted phenyl or anthracenyl group. R ⁹ is a divalent chain hydrocarbon group having 1 to 20 carbon atoms, and carbon at the chain hydrocarbon group. - a divalent group containing "-O-" between the carbon bonds. n4, n5, and n6 are each independently 0 or 1, and m2 is an integer of 0 to 2. "*" indicates a bonding bond.)

From the viewpoint of enhancing the sensitivity to light, the A ^{1 of} the formula (b2) preferably extends a phenyl group or a biphenyl group. X ⁴ is preferably -O-CO-* ³ , -S-CO-* ³ , -CO-O-* ³ or -CO-S-* ³ , more preferably -O-CO-* ³ or -S-CO- * ³ , and further preferably -S-CO-* ³ .

When the ring of R ⁸ and R ¹⁰ has a substituent, examples of the substituent include a fluorine atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, and a carbon number of 1. ~3 fluoroalkyl and the like. The position of the substituent is not particularly limited, but when "-CO-O-" or "-CO-S-" is bonded to the benzene ring of R ⁸ and R ¹⁰ with respect to "-CO-O-" or "-CO-S-", preferably ortho.

Preferably, at least one of n4 and n6 is 1. From the viewpoint of appropriately performing the development of the anisotropy by light irradiation, m2 is preferably 1 or 2.

R ^{9 is} more preferably a group represented by the formula (3). Further, by using the diamine in which the n5 in the formula (b2) is 1, and m2 is 1 or 2, a polylysine having a structure represented by the formula (3) in the main chain can be obtained (C). ).

From the viewpoint of improving the effect on the sensitivity of light, X ¹ in the formula (b) is preferably a sulfur atom, and from the viewpoint of availability, an oxygen atom is preferred.

Preferable specific examples of the group represented by the formula (b2) include a group represented by each of the following formulas (b2-1) to (b2-19).

(where "*" means the keying key)

As a group represented by the above formula (b2), from the viewpoint of enhancing the sensitivity of the polymer (C) to light, it is preferable that the formula (b2-2) to the formula (b2-5) and the formula (b2) -7) a group represented by each of the formulae (b2-9), (b2-13), and (b2-15) to (b2-19), more preferably by the formula (b2-2) a group represented by each of the formulae (b2-5), (b2-7) to (b2-9), (b2-18), and (b2-19).

Specific examples of the specific diamine used for the synthesis of the poly-proline in the present invention include 4-aminophenyl-4'-aminobenzoic acid ester (represented by the following formula (b-1) Compound), 3,3'-dimethyl-4-aminophenyl-4'-aminobenzoate, 3,3',5,5'-tetramethyl-4-aminophenyl -4'-aminobenzoic acid ester, 3-methyl-4-aminophenyl-4'-aminobenzoic acid ester, which is represented by the following formula (b-2) to formula (b-19) Compounds represented by the formulas and the like. In addition, as the specific diamine, one type of the compound may be used alone or two or more types may be used in combination.

[Other diamines]

In the case of the methods of [ii] and [iii], as the diamine for the synthesis of polylysine, only a specific diamine may be used, or a specific diamine may be used without the structure. The diamine of (Y) is used in combination. The diamine (hereinafter, also referred to as "other diamine") which does not have the structure (Y) which can be used in the method of the above [i] to [iii] may be an aliphatic diamine or an alicyclic two. An amine, an aromatic diamine, a diamine organic oxirane or the like. Among them, a diamine having a nitrogen-containing hetero ring, a diamine having a structure exhibiting a photosensitizing function, a diamine having a carboxyl group, a diamine having a spacer structure, or the like can be preferably used.

The diamine having a nitrogen-containing hetero ring has, for example, a nitrogen-containing hetero ring such as acridine, pyrrolidine, pyridine, pyrazine, pyridazine, pyrimidine or levoxazine, and two primary amino groups. It is preferable from the viewpoint of improving the effect of reducing the burn-in of the liquid crystal display element by using such a diamine in the synthesis of polyamic acid (C). Among them, a diamine having an acridine ring or a pyridazine ring as a nitrogen-containing hetero ring is preferable from the viewpoint of a high effect of reduction in sintering, and a diamine having an acridine ring is more preferable.

Specific examples of the diamine having a nitrogen-containing hetero ring include a compound represented by each of the following formulas (b3-1) to (b3-4).

The use ratio of the diamine having a nitrogen-containing hetero ring is preferably 40 mol% or less, and more preferably 30 mol% or less, based on the total amount of the diamine used for the synthesis. Further, the lower limit of the use ratio is not particularly limited, but in order to obtain an effect of improving the baking characteristics by using the diamine, it is preferably set to 1 mol% with respect to the total amount of the diamine used for the synthesis. the above. Further, by using the above-exemplified diamine having a nitrogen-containing hetero ring, polyamic acid (C) having a nitrogen-containing hetero ring in the main chain can be obtained.

In the diamine having a structure capable of exhibiting a light sensitizing function, the term "light sensitizing function" means that an intersystem crossing phenomenon is rapidly generated after a singlet excited state is caused by irradiation of light. The function of transforming the state into a triplet state. If a collision occurs with another molecule in the triplet state, the opponent is made to be in an excited state, and the self is restored to the basic state. The use of such a diamine in the synthesis of polyamic acid (C) is preferred from the viewpoint of enhancing the sensitivity of the polymer (C) to light. Specific examples of the diamine include 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, and {4-[2-(3,5-di). Aminophenoxy)-ethoxy]-phenyl}-ethanone, 3,4-diaminobenzophenone, {4-[2-(3,5-diaminophenoxy)- Ethoxy]-phenyl}-phenyl-methanone, {4-[2-(2,4-diaminophenoxy)-ethoxy]-phenyl}-phenyl-methanone, { 4-[2-(2,4-Diaminophenoxy)-ethoxy]-phenyl}-p-toluidine a benzophenone structure diamine such as ketone or {4-[2-(2,4-diaminophenoxy)-ethoxy]-phenyl}-o-tolylmethyl ketone-ketone A diamine having a fluorene structure such as 2,7-diaminofluorenone, 2,7-diamino fluorene or 9,9-bis(4-aminophenyl)fluorene.

From the viewpoint of suppressing the decrease in sensitivity caused by excessive introduction, the use ratio of the diamine having a structure exhibiting a photosensitizing function is preferably set to 20 mol% with respect to the total amount of the diamine used for the synthesis. Hereinafter, it is more preferably 15 mol% or less. Further, the lower limit of the use ratio is not particularly limited, but in order to sufficiently obtain the effect of the sensitivity increase by the use of the diamine, it is preferably set to 1 mol% with respect to the total amount of the diamine used for the synthesis. the above. Further, by carrying out polymerization using the diamine which exhibits a photosensitizing function, polylysine (C) having a structure having a photosensitizing function can be obtained.

The carboxyl group-containing diamine is a diamine having at least one carboxyl group and two primary amine groups. It is preferable from the viewpoint of further increasing the effect of reducing the burn-in of the liquid crystal display element by using the diamine in the polymerization of the polyamic acid (C). The carboxyl group-containing diamine is preferably an aromatic carboxylic acid, and specific examples thereof include 3,5-diaminobenzoic acid, 2,4-diaminobenzoic acid, and 2,5-diamino group. Monocarboxylic acid such as benzoic acid; 4,4'-diaminobiphenyl-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3 '-Diaminobiphenyl-4,4'-dicarboxylic acid, 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane- 3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-3-carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 4,4'-diamine Diphenylethane-3,3'-dicarboxylic acid, 4,4'-diaminodiphenylethane-3-carboxylic acid, 4,4'-diaminodiphenyl ether-3, Dicarboxylic acid such as 3'-dicarboxylic acid.

The ratio of use of the carboxyl group-containing diamine to the total amount of the diamine used for the synthesis is preferably 40% by mole or less, and more preferably 30% by mole or less. Further, the lower limit of the use ratio is not particularly limited, but in order to obtain an effect of improving the baking characteristics by using the diamine, it is preferably set to 1 mol% with respect to the total amount of the diamine used for the synthesis. the above.

The diamine having a spacer structure is a linear amine having a linear chain hydrocarbon group or a linear structure having a "-O-" group between carbon-carbon bonds in the hydrocarbon group, and examples thereof include A diamine or the like of the structure represented by the above formula (3). By using this diamine, the effect of the sensitivity improvement of the polymer (C) becomes high, and it is preferable.

Examples of the diamine having a spacer structure include aliphatic diamines such as 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine; and 4,4 '-Ethylene diphenylamine, an aromatic diamine such as a compound represented by the following formula (b4-1), or the like. Among them, an aromatic diamine is preferred.

The ratio of use of the diamine having a spacer structure is not particularly limited, but in order to sufficiently obtain the effect of the sensitivity increase by using the diamine, it is preferably set to 10 mol with respect to the total amount of the diamine used for the synthesis. More than or equal to the ear, more preferably 20 mol% or more. Further, by carrying out polymerization using the diamine having a spacer structure, polyamic acid (C) having a structure represented by the above formula (3) in the main chain can be obtained.

As the other diamine, a diamine other than the above compound can also be used. Make Specific examples of the diamines include, for example, m-xylylenediamine as the aliphatic diamine, and 1,4-diaminocyclohexane and 4,4'- as the alicyclic diamine. Methylene bis(cyclohexylamine), 1,3-bis(aminomethyl)cyclohexane, etc.; as the aromatic diamine, for example, p-phenylenediamine, 4,4'-diaminobiphenyl Methane, 4,4'-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'- Diamino-2,2'-bis(trifluoromethyl)biphenyl, 4,4'-diaminodiphenyl ether, 2,2-bis[4-(4-aminophenoxy)benzene Propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'- (p-phenylene diisopropyl) diphenylamine, 4,4'-(meta-phenyl diiso-propyl)diphenylamine, 1,4-bis(4-aminophenoxy)benzene, 4 , 4'-bis(4-aminophenoxy)biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diamine Acridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3 ,6-Diaminocarbazole, N,N'-bis(4-aminophenyl)-benzidine N,N'-bis(4-aminophenyl)-N,N'-dimethylbenzidine, 1,4-bis-(4-aminophenyl)-pyridazine, dodecyloxy- 2,4-Diaminobenzene, tetradecyloxy-2,4-diaminobenzene, pentadecyloxy-2,4-diaminobenzene, hexadecyloxy-2,4-di Aminobenzene, octadecyloxy-2,4-diaminobenzene, dodecyloxy-2,5-diaminobenzene, tetradecyloxy-2,5-diaminobenzene, ten Pentameryl-2,5-diaminobenzene, cetyloxy-2,5-diaminobenzene, octadecyloxy-2,5-diaminobenzene, cholestyloxy- 3,5-Diaminobenzene, cholestyloxy-3,5-diaminobenzene, cholestyloxy-2,4-diaminobenzene, cholesteneoxy-2,4-di Aminobenzene, cholesteryl 3,5-diaminobenzoic acid, cholesteryl 3,5-diaminobenzoic acid, lanostino 3,5-diaminobenzoic acid, 3 ,6-bis(4-aminobenzylideneoxy)cholestane, 3,6-bis(4-amine Benzophenoxy)cholestane, 4-(4'-trifluoromethoxybenzylideneoxy)cyclohexyl-3,5-diaminobenzoate, 4-(4'-trifluoromethyl Benzobenzyloxy)cyclohexyl-3,5-diaminobenzoate, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane Alkane, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-heptylcyclohexane, 1,1-bis(4-((aminophenoxy)methyl) Phenyl)-4-heptylcyclohexane, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-(4-heptylcyclohexyl)cyclohexane; For example, 1,3-bis(3-aminopropyl)-tetramethyldioxane and the like can be used as the diamine-based organic siloxane. In addition, Japanese Patent Laid-Open Publication No. 2010-97188 can be used. The diamine described in the above. As the diamine, one type of the above diamine may be used alone or two or more types may be used in combination.

In the method of the above [ii], from the viewpoint of obtaining a liquid crystal display element having good sensitivity to light, the use ratio of the specific diamine is preferably relative to the total amount of the synthetic diamine used for the polyamic acid. It is 30% by mole or more, more preferably 40% by mole or more, and still more preferably 50% by mole or more. Further, in the case of the method (iii), the use ratio of the specific diamine is preferably 1 mol% or more, more preferably 5 mol%, based on the total amount of the diamine used for the synthesis of polyglycine. More than 8% of the ear.

It is considered that the sensitivity of the polymer (C) to light is determined according to the total amount of the structure (Y) contained in the main chain of the polymer. Therefore, from the viewpoint of making the sensitivity of the polymer (C) to light good, it is particularly preferable to use the monomer for the synthesis of the polymer (C) as the specific tetracarboxylic dianhydride and the specific A combination of diamines.

The content of the structure (Y) in the polymer (C) is preferably from 1 × 10 ^-5 mol / g to 1 × 10 ^-2 mol / g, from the viewpoint of improving the sensitivity to light. More preferably, it is 5 × 10 ^-5 mol / g - 5 × 10 ^-3 mol / g. Therefore, it is preferable to set the type and amount of the specific tetracarboxylic dianhydride and the specific diamine to be used so that the content of the structure (Y) in the polymer (C) is within the above range.

Further, specific tetracarboxylic dianhydrides and specific ones are available for the purpose of exhibiting good sensitivity and burning characteristics, and high voltage holding ratio, and having a common structure (Y) in the main chain. Diamines all have the same effect. Therefore, it can be used in the present invention even if it is not described in the following examples. Further, the same applies to other tetracarboxylic dianhydrides and other diamines used together with a specific tetracarboxylic dianhydride or a specific diamine, and it can be used in the present invention even if it is not described in the following examples.

[Molecular weight regulator]

When the polyamic acid is synthesized, the tetracarboxylic dianhydride and the diamine as described above may be used together with a suitable molecular weight modifier to synthesize the terminal-modified polymer. By forming the terminal-modified polymer, the coating property (printability) of the photo-aligning agent can be further improved without impairing the effects of the present invention.

Examples of the molecular weight modifier include an acid monoanhydride, a monoamine compound, and a monoisocyanate compound. As specific examples thereof, examples of the acid monoanhydride include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decyl succinic anhydride, n-dodecyl succinic anhydride, and n-tetradecyl amber. An acid anhydride, n-hexadecyl succinic anhydride or the like; examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, and the like; as a monoisocyanate compound, For example, phenyl isocyanate, naphthyl isocyanate, etc. are 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, based on 100 parts by weight of the total of the tetracarboxylic dianhydride and the diamine to be used.

<Synthesis of polylysine>

The ratio of use of the tetracarboxylic dianhydride to the diamine for the synthesis reaction of the poly-proline in the present invention is preferably 1 equivalent to the amine group of the diamine, and the acid anhydride group of the tetracarboxylic dianhydride becomes 0.2 equivalent to 2 equivalents. More preferably, the acid anhydride group of the tetracarboxylic dianhydride becomes a ratio of 0.3 equivalent to 1.2 equivalent.

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

Here, examples of the organic solvent used for the reaction include an aprotic polar solvent, a phenol solvent, an alcohol, a ketone, an ester, an ether, a halogenated hydrocarbon, and a hydrocarbon.

Specific examples of the organic solvent include, as the aprotic polar solvent, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, and N-ethyl-2- Pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylhydrazine, γ-butyrolactone, tetramethylurea, hexamethylphosphonium triamine, etc.; Examples of the phenol-based solvent include phenol, m-cresol, xylenol, and halogenated phenol. Examples of the alcohol include methanol, ethanol, isopropanol, cyclohexanol, ethylene glycol, and propylene glycol. 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, etc., and examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and the like; Examples of the ester include ethyl lactate, butyl lactate, methyl acetate, and acetic acid. Ethyl ester, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, isoamyl propionate, isoamyl isobutyrate, diethyl oxalate, diethyl malonate, etc.; Examples of the ether include diethyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol-n-butyl ether, and ethylene glycol. Ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, two Ethylene glycol monoethyl ether acetate, tetrahydrofuran, etc.; examples of the halogenated hydrocarbon include dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, and the like. O-dichlorobenzene or the like; examples of the hydrocarbon include hexane, heptane, octane, benzene, toluene, xylene, and the like. Further, a compound corresponding to the first solvent and the second solvent shown below may be used.

Among these organic solvents, one or more selected from the group consisting of an aprotic polar solvent and a phenol solvent (A solvent), or one or more selected from the group consisting of A solvents and alcohols, ketones, and the like are preferably used. a mixture of one or more of the group consisting of esters, ethers, halogenated hydrocarbons, and hydrocarbons (B solvent). In the latter case, the use ratio of the B solvent is preferably 50 wt% or less, more preferably 40 wt% or less, still more preferably 30 wt% or less, based on the total amount of the A solvent and the B solvent.

The amount (a) of the organic solvent to be used is preferably such an amount that the total amount (b) of the tetracarboxylic dianhydride and the diamine becomes 0.1 wt% to 50 wt% with respect to the total amount of the reaction solution (a+b). %.

A reaction solution obtained by dissolving polylysine was obtained in the manner described. The reaction solution may be directly supplied to the preparation of the photo-aligning agent, or may be contained in the reaction solution. Some polylysine may be used for the preparation of the photo-aligning agent after segregation, or may be prepared for the photo-alignment agent after refining the isolated polylysine. In addition, when polypyridic acid is subjected to dehydration ring closure to form a polyimine, the reaction solution may be directly supplied to a dehydration ring-closure reaction, or may be obtained by isolating the polylysine contained in the reaction solution. The dehydration ring closure reaction may be carried out after the dehydration ring closure reaction or the isolated polyamic acid may be purified. The isolation and purification of polylysine can be carried out according to a known method.

<Polyurethane>

The polyphthalate contained in the photoalignment agent of the present invention has the above structure (Y) in the main chain. For example, the synthesis of such a polyperurethane (hereinafter also referred to as "polyperurethane (C)") can be carried out by [i] opening a tetracarboxylic dianhydride to form a dicarboxylic acid diester. a method of reacting the obtained dicarboxylic acid diester with a diamine in the presence of a dehydration catalyst; [ii] obtaining a diester diterpene chloride by using a tetracarboxylic dianhydride to obtain a diester diterpene chloride a method of reacting with a diamine; [iii] a method of esterifying the carboxyl group of the polyproline (C), and the like. Further, in the method [i] and the method [ii], by using at least one of the tetracarboxylic dianhydride and the diamine as the compound (Y), a polymer (C) can be obtained. Polyamide. As a method of synthesizing the polyglycolate (C), the method [i] in the method is preferably used.

In the case where the polyglycolate (C) of the present invention is synthesized by the method [i], it is obtained by a ring-opening reaction of tetracarboxylic dianhydride at the time of the synthesis reaction. In the case of a dicarboxylic acid diester, for example, an alcohol such as methanol or ethanol can be used.

The ratio of the dicarboxylic acid diester to the diamine obtained by the ring-opening reaction is preferably 1 equivalent to the amine group of the diamine, and the carboxyl group of the dicarboxylic acid diester is 0.2 to 2 equivalents, more preferably two. The carboxyl group of the carboxylic acid diester becomes a ratio of 0.3 equivalent to 1.2 equivalent. Further, as the tetracarboxylic dianhydride and the diamine used for the reaction, the description of the tetracarboxylic dianhydride and the diamine used in the synthesis of the polyamic acid (C) can be applied. Further, in the synthesis reaction, a dicarboxylic acid diester may be prepared instead of the ring opening of the tetracarboxylic dianhydride to obtain a dicarboxylic acid diester, and the compound is used as a starting material to synthesize the polyfluorene in the present invention. Amine ester (C).

The synthesis reaction of the polyamine ester (C) is preferably carried out in an organic solvent. The reaction temperature at this time is preferably -20 ° C to 80 ° C, more preferably 0 ° C to 60 ° C. Further, the reaction time is preferably from 0.5 to 48 hours, more preferably from 1.5 to 24 hours. The organic solvent used for the reaction is exemplified as an organic solvent exemplified as the organic solvent which can be used for the synthesis of the polyamic acid (C). In addition, the amount (a) of the organic solvent used is preferably such an amount that the total amount (b) of the dicarboxylic acid diester and the diamine becomes 0.1 wt% with respect to the total amount (a+b) of the reaction solution. 50 wt%.

Examples of the dehydrating solvent include 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium halide, carbonylimidazole, and phosphorus-based condensation. Agents, etc. The amount of the dehydration catalyst to be used is preferably 1.8 times to 4 times moles, more preferably 2.2 times to 3.5 times moles, relative to the amount of the dicarboxylic acid diester used for the reaction.

The synthesis reaction can be carried out in the presence of a base. As the base, for example, a trialkylamine such as triethylamine or an N-alkylmorpholine such as N-methylmorpholine can be preferably used. relatively The amount of the dicarboxylic acid diester used in the reaction is 1 mole, and the amount of the base used is preferably 0.5 to 3 moles, more preferably 0.7 to 2 moles.

A reaction solution obtained by dissolving polyglycolate was obtained in the manner described. The reaction solution may be directly supplied to the preparation of the photo-aligning agent, or may be prepared for the photo-alignment agent after segregating the polyphthalate contained in the reaction solution, or may also be used for the isolated poly-proline. The ester is refined and then supplied to the preparation of the photoalignment agent. The isolation and purification of the polyamidite can be carried out according to a known method.

<polyimine]

The polyimine (as hereinafter also referred to as "polyimine (C)")) as the polymer (C) contained in the photo-aligning agent of the present invention can be, for example, synthesized by the poly-proline as described above. (C) A dehydration ring closure is carried out to obtain a hydrazine imidization.

The polyimine (C) may be a fully ruthenium imide formed by dehydration ring closure of all of the proline structures of polyglycolic acid (C) as a precursor thereof, or may be only ruthenium A part of the structure of the amino acid is subjected to a dehydration ring closure, and a partial ruthenium imide of a guanidine structure and a quinone ring structure. The polyamidimide (C) in the present invention has a ruthenium iodide ratio of preferably 5% or more, more preferably 10% to 60%, still more preferably 15% to 50%. The ruthenium imidization ratio is a ratio of the number of quinone ring structures to the total number of guanidine structures and the number of quinone ring structures of the polyimine. Here, a part of the quinone ring may also be an isoindole ring.

The dehydration ring closure of polylysine is preferably carried out by (I) heating a polylysine; or (II) dissolving polylysine in an organic solvent, adding a dehydrating agent to the solution; Dehydration closed-loop catalyst and heating as needed law.

The reaction temperature in the method (I) is preferably from 50 ° C to 200 ° C, more preferably from 60 ° C to 170 ° C. The reaction time is preferably from 0.5 to 48 hours, more preferably from 2 to 20 hours.

Further, in the method (II), as the dehydrating agent, for example, an acid anhydride such as acetic anhydride, propionic anhydride or trifluoroacetic anhydride can be used. The amount of the dehydrating agent to be used is preferably from 0.01 mol to 20 mol based on 1 mol of the proline structure of the polyglycolic acid. As the dehydration ring-closing catalyst, for example, a tertiary amine such as pyridine, N-methylacridine, trimethylpyridine, lutidine or triethylamine can be used. The amount of the dehydration ring-closure catalyst used is preferably set to 0.01 mol to 10 mol with respect to 1 mol of the dehydrating agent to be used. The organic solvent used for the dehydration ring-closure reaction is exemplified as the organic solvent exemplified as the organic solvent used in the synthesis of polyglycine. The reaction temperature of the dehydration ring closure reaction is preferably from 0 ° C to 180 ° C, more preferably from 10 ° C to 150 ° C. The reaction time is preferably from 1.0 to 120 hours, more preferably from 2.0 to 30 hours. The dehydration ring closure of polylysine preferably utilizes the method of (II) of these methods.

The polyimine obtained in the method (I) may be directly supplied to the preparation of the photo-aligning agent, or may be supplied to the preparation of the photo-aligning agent after refining the obtained polyimine. On the other hand, in the method (II), a reaction solution containing polyiminoimine can be obtained. The reaction solution may be directly supplied to the preparation of the photo-aligning agent, or may be prepared for the photo-alignment agent after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution, or may be provided after the selenium imidization is isolated. Preparation of a photo-alignment agent, or may be provided to a photo-alignment agent after refining the isolated polyimine Preparation. These refining operations can be carried out according to a known method.

<Solid viscosity of polymer>

The polyamic acid (C), polyphthalate (C) and polyimine (C) obtained in the above manner preferably have a concentration of 10 m% when it is made into a solution having a concentration of 10 wt%. s~800 mPa. The solution viscosity of s is more preferably 15 mPa. s~500 mPa. s solution viscosity. Further, the solution viscosity (mPa.s) of the polymer is a concentration of 10 wt% prepared for a good solvent (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) using the polymer. The polymer solution was measured using an E-type rotational viscometer at 25 °C.

<weight average molecular weight of polymer>

The polyamic acid (C), polyphthalate (C), and polyimine (C) are preferably polystyrene-reduced weight averages measured by Gel Permeation Chromatography (GPC). The molecular weight is from 500 to 500,000, and more preferably the weight average molecular weight is from 1,000 to 300,000.

From the viewpoint of sufficiently obtaining the effect of the present invention, the content ratio of the polymer (C) in the photo-aligning agent is preferably 10 parts by weight based on 100 parts by weight of the total of the polymer component contained in the photo-aligning agent. The above is more preferably 20 parts by weight or more, and still more preferably 30 parts by weight or more.

<Other ingredients>

The photoalignment agent of the present invention may contain other components as needed. Examples of the other component include a polymer other than the polymer (C) and a compound having at least one epoxy group in the molecule (hereinafter referred to as "epoxy group-containing compound". ")", a functional decane compound, a photosensitizer, and the like.

[Other polymers]

The other polymers can be used to improve solution properties or electrical properties. The other polymer may, for example, be a polylysine obtained by reacting the other tetracarboxylic dianhydride with the other diamine (hereinafter also referred to as "other polylysine") or a poly A phthalate (hereinafter also referred to as "other polyphthalate"), a polyimine which is obtained by dehydration ring closure of the other polyamine (hereinafter also referred to as "other polyimine") ), polyester, polyamine, polyorganosiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly(styrene-phenylmethylene iodide) derivative, poly( Methyl) acrylate or the like.

When other polymers are added to the photo-aligning agent, the compounding ratio is preferably 90% by weight or less, more preferably 80% by weight or less, and still more preferably 70%, based on the total amount of the polymer in the composition. Below wt%.

[Epoxy group-containing compound]

The epoxy group-containing compound can be used to enhance the adhesion or electrical properties of the liquid crystal alignment film to the substrate surface. Here, examples of the epoxy group-containing compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether. , neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, trimethylolpropane triglycidyl ether, 2,2-dibromo neopentyl glycol condensate Glycerol ether, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N , N', N'-tetraglycidyl-4,4'-diaminodiphenyl Preferred examples of the alkane, N,N-diglycidyl-benzylamine, N,N-diglycidyl-aminomethylcyclohexane, N,N-diglycidyl-cyclohexylamine and the like. Further, as the epoxy group-containing compound, an epoxy group-containing polyorganosiloxane having the disclosure of WO 2009/096598 can be used. When these epoxy compounds are added to the photo-aligning agent, the compounding ratio is preferably 40 parts by weight or less, more preferably 0.1 parts by weight to 30 parts by weight, based on 100 parts by weight of the total of the polymers contained in the photo-aligning agent.

[functional decane compound]

The functional decane compound can be used for the purpose of improving the printability of the photoalignment agent. Examples of such a functional decane compound include 3-aminopropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 2-aminopropyltrimethoxydecane, and 2-amino group. Propyltriethoxydecane, N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldi Methoxydecane, 3-ureidopropyltrimethoxydecane, 3-ureidopropyltriethoxydecane, N-ethoxycarbonyl-3-aminopropyltrimethoxydecane, N-triethyl Oxymethalylpropyltriethylenetriamine, 10-trimethoxycarbamimidyl-1,4,7-triazadecane, 9-trimethoxyformamidin-3,6-diazepine Acetate, methyl 9-trimethoxycarbamido-3,6-diazanonanoate, N-benzyl-3-aminopropyltrimethoxydecane, N-phenyl-3-amine Propyltrimethoxydecane, glycidoxymethyltrimethoxydecane, 2-glycidoxyethyltrimethoxydecane, 3-glycidoxypropyltrimethoxydecane, and the like. When these functional decane compounds are added to the photo-aligning agent, the compounding ratio is preferably 2 parts by weight or less, more preferably 0.02 parts by weight to 0.2 parts by weight, based on 100 parts by weight of the total of the polymer.

[Light sensitizer]

The photosensitizer is a compound having a photosensitizing function that exhibits a sensitizing action by light irradiation, and can be used for the purpose of promoting photoreaction with a lifting sensitivity in combination with the polymer (C). Examples of such a photosensitizer include acetophenone, acetophenone benzyl ketal, 2,2-dimethoxy-2-phenylacetophenone, 3-methylacetophenone, and Benzophenone, 4-diethylamino-2-hydroxybenzophenone, 2-hydroxybenzophenone, 4-methylbenzophenone, 3,4-dimethylbenzophenone, 3- (4-Benzylmercapto-phenoxy)propyl, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-diaminobenzophenone, 4,4'-bis(dimethylamino)benzophenone, benzil, fluoranthene, 3,5-dinitrobenzene, 4-methyl-3,5-dinitrobenzene Benzobenzene, anthracene, anthrone, benzaldehyde, anthracene, triphenylamine, carbazole, benzoin, 2-naphthylacetone, 1-naphthylethyl ketone, benzoin ethyl ether, thioxanthone, two Ethyl thioxanthone, 2-isopropyl thioxanthone, 2-chlorothiazinone, and the like. From the viewpoint of obtaining good sensitivity, the compounding ratio of the photosensitizer is usually from 0.1 part by weight to 15 parts by weight, preferably from 3 parts by weight to 10 parts by weight, based on 100 parts by weight of the total of the polymer.

Further, as the other component, in addition to the above components, an additive which is usually added to the photo-aligning agent, for example, a compound having at least one oxetanyl group in the molecule, an antioxidant, or the like can be used.

In a preferred embodiment of the photo-aligning agent of the present invention, the polymer component may be, for example, the following: (I) only comprising a polyphthalic acid (C), a polyamidomate (C), and a polyfluorene. a form of one of the groups consisting of imines (C); (II) a form comprising at least one selected from the group consisting of polyaminic acid (C) and polypyridamine (C) and other polyamidene; (III) comprising polyimine (C) And a form of poly-polyglycolic acid; (IV) comprising at least one selected from the group consisting of poly-proline (C) and polyimine (C), and polyglycolate (C) Form (V) comprising at least one selected from the group consisting of poly-proline (C), polyphthalate (C), and polyimine (C) with other polymers, and other polymers It is a form selected from at least one of the group consisting of other poly-proline, other polyamidomate, and other polyimine.

Among these forms, it is preferable that the form of the polyimine is used to improve the mechanical strength and the voltage holding ratio. Specifically, the form of the above (II) or the above (III) is preferable. The form is more preferably the form of the above (III). Moreover, it is preferable to further reduce the baking of a liquid crystal display element by the form containing a poly phthalate, and it is preferable to contain only a poly phthalate in the above (I). The form of C) or the form of the above (IV) is more preferably a form in which only the polyphthalate (C) is contained in the above (I). Further, the blending ratio of the polyamine, the polyphthalate, and the polyimine in each form can be arbitrarily set in accordance with the use of the liquid crystal display element to be applied or the like.

<solvent>

The photo-aligning agent of the present invention is preferably formed by dissolving a polymer component or other component arbitrarily arbitrarily dissolved in an organic solvent.

As the solvent used in the preparation of the photoalignment agent of the present invention, it can be used. A solvent which can dissolve the polymer contained in the photo-aligning agent. Further, a poor solvent of the polymer may be used in combination within a range in which the polymer contained in the photo-aligning agent does not precipitate. Specifically, the solvent to be used in the preparation of the photo-alignment agent of the present invention is preferably at least one of the first solvent represented by the following [A] and the second solvent represented by the following [B]. More preferably, the first solvent and the second solvent are simultaneously contained.

[A] is at least one selected from the group consisting of a compound represented by the following formula (4), a compound represented by the following formula (5), and 1,3-dimethyl-2-imidazolidinone. The first solvent.

(In the formula (4), R ¹¹ is a monovalent hydrocarbon group having 2 to 5 carbon atoms or a monovalent group having "-O-" in a carbon-carbon bond in the hydrocarbon group.)

(In the formula (5), R ¹² and R ¹³ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a monovalent "-O-" having a carbon-carbon bond between the hydrocarbon groups; , R ¹² and R ¹³ may be bonded to each other to form a ring structure. R ¹⁴ is an alkyl group having 1 to 6 carbon atoms)

[B] is at least one selected from the group consisting of a compound represented by the following formula (6), a compound represented by the following formula (7), and a compound represented by the following formula (8). 2 solvent.

(In the formula (6), R ¹⁵ and R ¹⁷ are each independently a monovalent hydrocarbon group having 1 to 3 carbon atoms, and R ¹⁶ is an alkanediyl group having 2 to 5 carbon atoms.)

R ¹⁸ -OR ¹⁸ (7)

(In the formula (7), R ¹⁸ is a monovalent oxy group containing one "-O-" between carbon-carbon bonds of a linear or branched alkyl group having 3 to 5 carbon atoms, or a branched alkyl group having a carbon number of 3 to 5)

(In the formula (8), X ⁵ is -C(OH)R ^a - (wherein R ^a is an alkyl group having 1 or 2 carbon atoms), -CO- or -COO-* (where * represents R ^{19 is} a bonding bond), and R ¹⁹ is an alkyl group having 1 to 4 carbon atoms.)

Hereinafter, the first solvent and the second solvent will be described separately.

[1st solvent]

(compound represented by formula (4))

In the first solvent, the compound represented by the formula (4), the monovalent hydrocarbon group having 2 to 5 carbon atoms of R ¹¹ is preferably a chain hydrocarbon group, and examples thereof include an alkane having 2 to 5 carbon atoms. Base, alkenyl, alkynyl and the like. In addition, examples of the monovalent group containing "-O-" between the carbon-carbon bonds in the hydrocarbon group include an alkoxyalkyl group having 2 to 5 carbon atoms.

Specific examples of the alkyl group include, for example, an ethyl group, a propyl group, a butyl group, and a pentyl group, and examples of the alkyl group having 2 to 5 carbon atoms; and examples of the alkenyl group having 2 to 5 carbon atoms include a vinyl group. a 1-propenyl group, a 2-propenyl group, a 3-butenyl group or the like; and examples of the alkynyl group having 2 to 5 carbon atoms include an ethynyl group, a 2-propynyl group, a 2-butynyl group, and the like; The alkoxyalkyl group having a number of 2 to 5 may, for example, be a methoxymethyl group, a methoxyethyl group, a methoxypropyl group, a methoxybutyl group, an ethoxymethyl group or an ethoxyethyl group. Etc.; these groups may be linear or branched. As R ¹¹ , among the above groups, an alkyl group having 2 to 5 carbon atoms or an alkoxyalkyl group is preferable.

Specific examples of the compound represented by the formula (4) include N-ethyl-2-pyrrolidone, N-(n-propyl)-2-pyrrolidone, and N-isopropyl-2-pyrrolidone. , N-(n-butyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N Ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone, and the like. Among these compounds, N-ethyl-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-(tert-butyl)-2-pyrrolidone, N-methoxypropyl- can be preferably used. 2-pyrrolidone. In addition, the compound represented by the formula (4) may be used alone or in combination of two or more.

(compound represented by formula (5))

In the first solvent, the compound represented by the formula (5), and the monovalent hydrocarbon group having 1 to 6 carbon atoms of R ¹² and R ¹³ may, for example, be a chain having 1 to 6 carbon atoms. A hydrocarbon group, an alicyclic hydrocarbon group having 3 to 6 carbon atoms, an aromatic hydrocarbon group having 5 or 6 carbon atoms, and the like. In addition, examples of the monovalent group containing "-O-" between the carbon-carbon bonds of the hydrocarbon group include an alkoxyalkyl group having 2 to 6 carbon atoms.

Specific examples of the bases include, as a chain hydrocarbon group having 1 to 6 carbon atoms, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc., and these groups may be linear or may be used. It is branched. In addition, examples of the alicyclic hydrocarbon group having a carbon number of 3 to 6 include a cyclopentyl group and a cyclohexyl group; and examples of the aromatic hydrocarbon group include a phenyl group; and the alkoxyalkyl group having a carbon number of 2 to 6; Examples of the group include a compound listed in R ¹¹ and the like. Further, R ¹² and R ¹³ in the formula (5) may be the same as or different from each other. Further, R ¹² and R ¹³ may form a ring together with a nitrogen atom to which R ¹² and R ¹³ are bonded by mutual bonding. Examples of the ring formed by bonding R ¹² and R ^{13 to} each other include a pyrrolidine ring and an acridine ring, and a monovalent chain hydrocarbon group such as a methyl group may be bonded to these rings.

R ¹² and R ^{13 are} preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom or a methyl group.

Examples of the alkyl group having 1 to 6 carbon atoms of R ¹⁴ include the groups exemplified in the description of the alkyl group having 1 to 6 carbon atoms of R ¹² and R ¹³ .

Specific examples of the compound represented by the formula (5) include 3-butoxy-N,N-dimethylpropane decylamine and 3-methoxy-N,N-dimethyl group. Propane decylamine, 3-hexyloxy-N,N-dimethylpropane decylamine, isopropoxy-N-isopropyl-propionamide, n-butoxy-N-isopropyl-propionamide Wait. In addition, the compound represented by the formula (5) may be used alone or in combination of two or more.

In particular, the first solvent is preferably at least one selected from the group consisting of the compound represented by the formula (4) and 1,3-dimethyl-2-imidazolidinone, and more preferably selected from the group consisting of In the compound represented by the formula (4), a group consisting of a compound wherein R ¹¹ is an alkyl group having 2 to 5 carbon atoms or an alkoxyalkyl group, and 1,3-dimethyl-2-imidazolidinone At least one of the groups.

From the viewpoint of appropriately suppressing the precipitation of the polymer component on the printing machine when printing on the substrate, the first amount is the total amount of the solvent contained in the photo-aligning agent. The amount of the solvent used is preferably 5 wt% or more, and more preferably 10 wt% or more. In addition, the upper limit of the amount of use is not particularly limited, but is preferably 95% by weight or less, and more preferably 90% by weight or less based on the total amount of the solvent contained in the photo-aligning agent. As the first solvent, one type of the compound may be used alone or two or more types may be used in combination.

Further, since the first solvent dissolves the polymer (C) and has a relatively high boiling point, it is presumed that the first solvent is used as a solvent component of the liquid crystal alignment agent to suppress the photo-alignment agent when it is printed on the substrate. The solvent is volatilized from the printing machine, and precipitation of the polymer component can be suppressed, and as a result, printability (especially continuous printing property) can be improved.

[2nd solvent]

(compound represented by formula (6))

In the case of the compound represented by the above formula (6), the hydrocarbon group having 1 to 3 carbon atoms in R ¹⁵ and R ¹⁷ may, for example, be a methyl group, an ethyl group, a n-propyl group or an isopropyl group. The alkyl group having a carbon number of 1 to 3 or the like; a monovalent unsaturated hydrocarbon group having a carbon number of 2 or 3 such as a vinyl group or an allyl group. Among these groups, R ¹⁵ and R ^{17 are} preferably a methyl group or an ethyl group. Further, R ¹⁵ and R ¹⁷ may be the same or different from each other.

Examples of the alkanediyl group having 2 to 5 carbon atoms of R ¹⁶ include an exoethyl group, a propane-1,2-diyl group, a propane-1,3-diyl group, a butane-1,3-diyl group, and a butyl group. Alkyl-1,4-diyl, pentane-1,5-diyl and the like.

Preferable specific examples of the compound represented by the above formula (6) include an alkylene glycol diacetate such as ethylene glycol diacetate or propylene glycol diacetate. Acid ester. Among them, propylene glycol diacetate can be preferably used. As the compound represented by the formula (6), one type of the compound may be used alone or two or more types may be used in combination.

(compound represented by formula (7))

The compound represented by the above formula (7) has two R ¹⁸ groups via an ether bond. Specific examples of such a compound include, as the compound having an oxygen group in the case of R ¹⁸ , diethylene glycol dimethyl ether, diethylene glycol diethyl ether or the like; and a compound in which R ¹⁸ is a branched alkyl group. Examples thereof include diisopropyl ether, diisoamyl ether, di-sec-butyl ether, and di-sec-pentyl ether. As the compound represented by the above formula (7), among these compounds, at least one of diethylene glycol diethyl ether and diisoamyl ether is preferable. In addition, as the compound represented by the formula (7), one type of the compound may be used alone or two or more types may be used in combination.

(compound represented by formula (8))

X ⁵ in the formula (8) is preferably a group "-C(OH)R ^a -", more preferably a group "-C(OH)(CH ₃ )-". Further, the alkyl group having 1 to 4 carbon atoms of R ¹⁹ may be linear or branched, and is preferably a methyl group or an ethyl group.

Preferable specific examples of the compound represented by the above formula (8) include diacetone alcohol, acetamidineacetone, ethyl acetate ethyl acetate, and the like, and diacetone alcohol is particularly preferably used. In addition, as the compound represented by the formula (8), one type of the compound may be used alone or two or more types may be used in combination.

In particular, the second solvent is more preferably selected from the group consisting of the compound represented by the formula (6) and the compound represented by the formula (8). There is one less, and a compound represented by the above formula (8) is more preferable.

From the viewpoint of suppressing the precipitation of the polymer and improving the coatability (printability) of the substrate, the amount of the second solvent used is preferably 1 wt% with respect to the total amount of the solvent contained in the photo-aligning agent. 70 wt%, more preferably 3 wt% to 60 wt%. As the second solvent, one type of the above-mentioned compounds may be used alone or two or more types may be used in combination.

In addition, the ratio of the first solvent to the second solvent is preferably 0.03 times the amount of the second solvent used for the amount of the first solvent. The weight is more than 0.05 times by weight or more. In addition, the amount of the second solvent to be used relative to the amount of the first solvent is preferably 2.5 times by weight or less, and more preferably 2.0 times by weight or less, from the viewpoint of suppressing the precipitation of the polymer.

In addition, it is presumed that the second solvent is a solvent which is not easily swelled by APR (registered trademark, the same applies hereinafter) of a printing plate of a printing machine which is generally used for coating a photo-aligning agent on a substrate, and The solvent is less likely to be immersed in the printing plate at the time of printing, and the printability (especially continuous printability) can be made good.

[3rd solvent]

As the solvent contained in the photo-alignment agent of the present invention, other solvents (third solvent) other than the first solvent and the second solvent may be used. Examples of the third solvent include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, and N,N-dimethyl group. Acetamine, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, B Glycol ether, ethylene glycol-n-propyl ether, ethylene glycol-isopropyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol Alcohol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, Dipropylene Glycol Monomethyl Ether (DPM), diisobutyl ketone , isoamyl propionate, isoamyl isobutyrate, ethylene carbonate, propylene carbonate and the like. The third solvent may be used alone or in combination of two or more.

The content of the third solvent is preferably 80% by weight or less, more preferably 70% by weight or less, still more preferably 50% by weight or less, and particularly preferably 30% by weight or less, based on the total amount of the solvent contained in the liquid crystal alignment agent.

The solid content concentration in the photo-alignment agent of the present invention (the ratio of the total weight of the components other than the solvent of the liquid crystal alignment agent to the total weight of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, etc., but is preferably selected. A range of 1 wt% to 10 wt%. In other words, the photo-aligning agent of the present invention is applied to the surface of the substrate as described later, and is preferably heated to form a coating film to be a liquid crystal alignment film. However, in this case, when the solid content concentration is less than 1 wt%, the coating film is formed. The film thickness becomes too small to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, the film thickness of the coating film becomes too large, and it is difficult to obtain a favorable liquid crystal alignment film, and the viscosity of the photo-alignment agent increases and the coating property deteriorates.

The range of the particularly preferable solid content concentration differs depending on the method used when the photo-aligning agent is coated on the substrate. For example, in the case of using the rotator method, it is particularly preferable to set the solid content concentration to a range of 1.5 wt% to 4.5 wt%. Using printing In the case of the method, it is particularly preferable to set the solid content concentration to a range of 3 wt% to 9 wt%, thereby making the solution viscosity 12 mPa. s~50 mPa. The scope of s. In the case of using the inkjet method, it is particularly preferable to set the solid content concentration to a range of 1 wt% to 5 wt%, thereby making the solution viscosity 3 mPa. s~15 mPa. The scope of s. The temperature at which the photo-aligning agent of the present invention is prepared is preferably from 10 ° C to 50 ° C, more preferably from 20 ° C to 30 ° C.

<Liquid alignment film>

The liquid crystal alignment film in the present invention is formed by a photoalignment method using a photoalignment agent prepared as described above. The liquid crystal alignment film is preferably applied to a liquid crystal display element of a TN type, an STN type or a transverse electric field type. Among them, in particular, it is preferably applied to a liquid crystal display element of a transverse electric field type such as an IPS type or an FFS type, thereby maximizing the effect of reducing the adhesion of the liquid crystal display element.

The liquid crystal alignment film in the present invention can be produced by a film forming step of applying a photo-aligning agent of the present invention onto a substrate to form a coating film, and a light irradiation step of performing the coating film formed. Light is irradiated to form a liquid crystal alignment film.

[Film formation step]

In this step, the photoalignment liquid crystal alignment agent of the present invention is applied onto a substrate, and then the coated surface is heated to form a coating film on the substrate.

When applied to a TN type or STN type liquid crystal display element, two sheets of the substrate on which the patterned transparent conductive film is provided are paired, and then the photoalignment agent of the present invention is applied to each of the two substrates to be transparently conductive. A coating film is formed on the formed surface of the film. On the other hand, when applied to a liquid crystal display element of a transverse electric field mode, one will be The substrate having the electrode including the patterned transparent conductive film or the metal film is paired with the opposite substrate not provided with the electrode, and then the photo-aligning agent of the present invention is applied to the forming surface and the opposite side of the electrode, respectively. A coating film is formed on one side of the substrate.

In either case, as the substrate, for example, glass such as float glass, soda glass, or the like may be used, including, for example, polyethylene terephthalate, polybutylene terephthalate, polyether oxime, polycarbonate. A transparent substrate of plastic. As the transparent conductive film, for example, an ITO film containing In ₂ O ₃ —SnO ₂ , a NESA (registered trademark) film containing SnO ₂ , or the like can be used. As the metal film, for example, a film containing a metal such as chromium can be used. For the patterning of the transparent conductive film and the metal film, for example, a method of forming a pattern by a photolithography method, a sputtering method, or the like after forming a transparent conductive film having no pattern, and a method of forming a transparent conductive film may be used. A method of masking a desired pattern. Further, when the photo-aligning agent is applied, in order to improve the adhesion between the substrate, the conductive film or the electrode and the coating film, the surface on which the coating film is formed on the surface of the substrate may be coated with a functional decane compound and functionality. Pretreatment of titanium compounds and the like.

The application of the liquid crystal alignment agent to the substrate is preferably carried out by a coating method such as an offset printing method, a spin coating method, a roll coater method, or an inkjet printing method. After the application of the photoalignment agent, in order to prevent sag of the applied liquid crystal alignment agent, etc., it is preferable to carry out preheating (prebaking) (prebaking step). The prebaking temperature is preferably 30 ° C to 200 ° C, more preferably 40 ° C to 150 ° C, and particularly preferably 40 ° C to 100 ° C. The prebaking time is preferably from 0.25 minutes to 10 minutes, more preferably from 0.5 minutes to 5 minutes. Thereafter, the solvent is completely removed, and if necessary, a post-baking step of calcining the pre-baked coating film is carried out for the purpose of thermally imidating the proline structure present in the polymer. The post-baking temperature at this time is preferably 80 ° C to 300 ° C, more preferably 120 ° C to 250 ° C. The post-baking time is preferably from 5 minutes to 200 minutes, more preferably from 10 minutes to 100 minutes. The film thickness of the coating film after post-baking is preferably 0.001 μm to 1 μm, and more preferably 0.005 μm to 0.5 μm.

[Light irradiation step]

In this step, the coating film formed on the substrate is irradiated with polarized or non-polarized radiation, thereby imparting liquid crystal alignment ability. The radiation irradiation can be performed by the following method: [1] a method of irradiating the coating film after the post-baking step; [2] a method of irradiating the coating film before the pre-baking step and the post-baking step; [3] A method of irradiating a coating film during heating of a coating film in at least one of a prebaking step and a post baking step. The method [2] is preferred from the viewpoint that the effect of reducing the burn-in in the liquid crystal display element is higher.

As the radiation, for example, ultraviolet light or visible light containing light having a wavelength of 150 nm to 800 nm can be used. When the radiation is polarized, it may be linearly polarized or partially polarized. Further, when the radiation to be used is linearly polarized or partially polarized, the irradiation may be performed from a direction perpendicular to the substrate surface, or may be performed from an oblique direction, or may be performed by combining the two. When the non-polarized radiation is irradiated, the direction of the irradiation is set to the oblique direction.

As the light source to be used, for example, a low pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser or the like can be used. The ultraviolet light in a preferred wavelength region can be obtained by a method in which a light source is used in combination with, for example, a filter, a diffraction grating, or the like. The irradiation amount of the radiation is preferably 100 J/m ² to 50,000 J/m ² , and more preferably 300 J/m ² to 20,000 J/m ² . Further, in order to improve the reactivity, light irradiation to the coating film can be performed while the coating film is warmed. The temperature at the time of warming is usually from 30 ° C to 250 ° C, preferably from 40 ° C to 200 ° C, more preferably from 50 ° C to 150 ° C. Thus, a liquid crystal alignment film is formed on the substrate.

<Liquid crystal display element>

The liquid crystal display element of the present invention comprises the liquid crystal alignment film obtained in the above manner. The liquid crystal display element of the present invention can be produced, for example, in the following manner. First, a pair of substrates in which the liquid crystal alignment film is formed as described above is prepared, and a liquid crystal cell having a liquid crystal sandwiched between the pair of substrates is manufactured. When manufacturing a liquid crystal cell, the following two methods are mentioned, for example. The first method is a method that has been known from the past. This method is as follows. First, two substrates are placed facing each other with a gap (cell gap) interposed therebetween, and the peripheral portions of the two substrates are bonded together by a sealant, and the surface of the substrate is sealed. After filling the liquid crystal into the cell gap divided by the agent, the injection hole is sealed, thereby manufacturing a liquid crystal cell.

The second method is a method called the One Drop Fill (ODF) method. First, a sealing agent such as an ultraviolet curable layer is applied to a predetermined position on one substrate, and the liquid crystal is added dropwise to the liquid crystal alignment film surface, and then the other substrate is bonded to the liquid crystal alignment film in the opposite direction, and then The entire surface of the substrate is irradiated with ultraviolet light to harden the sealant, thereby manufacturing a liquid crystal cell. In the case of using any of the methods, it is preferred to heat the liquid crystal cell until the liquid crystal to be used obtains the temperature of the isotropic phase, and then slowly cool to room temperature, thereby removing the flow alignment when the liquid crystal is filled. Then, the polarizing plate is attached to the outer surface of the liquid crystal cell, thereby The liquid crystal display element of the present invention can be obtained. Further, when the radiation is linearly polarized, the angle formed by the polarization direction of the irradiated radiation and the angle between each substrate and the polarizing plate are appropriately adjusted for the two substrates on which the liquid crystal alignment film is formed, whereby desired Liquid crystal display element.

As the sealant, for example, an epoxy resin containing an alumina ball as a spacer and a curing agent can be used.

For the liquid crystal, for example, a nematic liquid crystal or a smectic liquid crystal can be used. Among them, a liquid crystal having a positive dielectric anisotropy of a nematic liquid crystal is preferably used. For example, a biphenyl liquid crystal or a phenylcyclohexane can be used. Liquid crystal, ester liquid crystal, terphenyl liquid crystal, biphenyl cyclohexane liquid crystal, pyrimidine liquid crystal, dioxane liquid crystal, bicyclooctane liquid crystal, cetane liquid crystal, or the like. Further, for example, the following compounds may be added to the liquid crystal: cholesteric liquid crystal such as cholesteryl cholesteryl, cholesteryl phthalate or cholesteryl carbonate; as the trade names "C-15" and "CB-15" (a chiral agent sold by Merck); a ferroelectric liquid crystal such as a nonoxybenzylidene-p-amino-2-methylbutyl cinnamate or the like.

Examples of the polarizing plate include a polarizing plate in which a polarizing film called "H film" is sandwiched between a cellulose acetate protective film, and a polarizing plate including an H film itself, which is oriented to extend polyvinyl alcohol on one side. A polarizing film that absorbs iodine.

The liquid crystal display element of the present invention has a liquid crystal alignment film formed by the photoalignment method using the photoalignment agent of the present invention, thereby exhibiting a wide viewing angle characteristic and high quality especially when applied to a liquid crystal display element of a transverse electric field type. The characteristics are displayed, and the burn-in is small, and the high voltage holding ratio is displayed. Therefore, the liquid crystal display of the present invention The display element can be effectively applied to various devices, for example, it can be suitably used as a clock, a portable game machine, a word processor, a notebook personal computer, a car navigation system, a camcorder, a personal digital assistant (PDA). Liquid crystal display elements used in various display devices such as digital still cameras, mobile phones, smart phones, various monitors, liquid crystal televisions, and information displays.

[Examples]

Hereinafter, the present invention will be specifically described by examples, but the present invention is not limited by the examples.

The weight average molecular weight of each polymer in the synthesis example and the solution viscosity of each polymer solution were measured by the following methods.

[weight average molecular weight of polymer]

The weight average molecular weight Mw of the polymer is a value in terms of polystyrene measured by gel permeation chromatography under the following conditions.

Pipe column: manufactured by Tosoh (shares), TSKgelGRCXLII

Solvent: tetrahydrofuran

Temperature: 40 ° C

Pressure: 68 kgf/cm ²

[Solid viscosity of polymer solution]

Solution viscosity of polymer solution [mPa. s] is a solution in which the polymer concentration was adjusted to 10 wt% using N-methyl-2-pyrrolidone (NMP), and the measurement was carried out at 25 ° C using an E-type rotational viscometer.

[Determination of sulfhydrylation rate]

The solution of polyimine is put into pure water, and the obtained precipitate is sufficiently dried under reduced pressure at room temperature, and then dissolved in deuterated dimethyl hydrazine, and tetramethyl decane is used as a reference substance. ¹ H-NMR was measured at room temperature. From the ¹ H-NMR spectrum obtained, the oxime imidization ratio [%] was determined by the formula represented by the following formula (1).

醯imination rate [%]=(1-A ¹ /A ² ×α)×100...(1)

(In the formula (1), A ¹ is the peak area of the proton derived from the NH group appearing near the chemical shift of 10 ppm, A ² is the peak area derived from other protons, and α is the precursor of the other proton to the polymer. (proportion of the number of protons of the NH group in (polyproline))

<Synthesis of tetracarboxylic dianhydride>

[Example 1]

In a 2000 mL three-necked flask to which a stirrer was added, 93.3 g of trimellitine chloride was added, and 450 g of tetrahydrofuran was added, followed by stirring to dissolve. Thereafter, the mixture was cooled to 0 ° C, and 30.0 g of 1,4-phenyldithiol dissolved in 200 g of pyridine was slowly added dropwise thereto, and stirred at room temperature for 20 hours. The solid precipitated at this time was removed by filtration, and the filtrate was poured into 500 g of hexane to carry out reprecipitation, and then the precipitate was collected by filtration (white solid). This white solid was recrystallized with 200 g of acetic anhydride to obtain 21.2 g of the compound (A-3) represented by the formula (a-3).

[Embodiment 2]

In addition to using 4,4'-biphenyldithiol 46.1 g instead of 1,4-benzenedithiol, and changing the amount of hexane in the reprecipitation to 2,500 g, In the same manner as in Synthesis Example 1, 26.3 g of the compound (A-4) represented by the formula (a-4) was obtained.

<Synthesis of polylysine>

[Synthesis Example 1]

4.48 g (0.0106 mol) of the compound (A-1) represented by the formula (a-1) and 1.155 g (0.0107 mol) of p-phenylenediamine as a diamine as a tetracarboxylic dianhydride In NMP 54 g, and reacted at room temperature for 6 hours. Thus, a solid concentration of 10% and a solution viscosity of 130 mPa were obtained. 59 g of poly-proline solution of s. This polyamic acid was used as the polymer (C-1).

[Synthesis Example 2]

The compound (A-2) represented by the formula (a-2), 4.982 g (0.0093 mol), and the p-phenylenediamine 1.018 g (0.0094 mol) as a diamine, were dissolved as tetracarboxylic dianhydride. In NMP 54 g, and reacted at 60 ° C for 6 hours. Thus, a solid concentration of 10% and a solution viscosity of 154 mPa were obtained. 59 g of poly-proline solution of s. This polyamic acid was used as the polymer (C-2).

[Example 3]

Compound (A-3) as a tetracarboxylic dianhydride 4.907 g (0.0100 mol), p-phenylenediamine 1.093 g (0.0101 mol) as a diamine was dissolved in NMP 54 g, and reacted at room temperature. 10 hours. Thus, a solid concentration of 10% and a solution viscosity of 115 mPa were obtained. 59 g of poly-proline solution of s. This polyaminic acid was used as the polymer (C-3).

[Example 4]

5.449 g (0.0096 mol) of compound (A-4) as a tetracarboxylic dianhydride, and 1.051 g (0.0097 mol) of p-phenylenediamine as a diamine were dissolved in NMP 58.5 g, and reacted at 60 ° C. 10 hours. Thus, a solid concentration of 10% and a solution viscosity of 137 mPa were obtained. 59 g of poly-proline solution of s. This polyaminic acid was used as the polymer (C-4).

[Synthesis Example 3]

4.92 g (0.0078 mol) of the compound (A-2) as a tetracarboxylic dianhydride, and 1.808 g (0.0079 mol) of the compound (B-1) represented by the formula (b-1) as a diamine. Dissolved in NMS 54.0 g and reacted at room temperature for 10 hours. Thus, a solid concentration of 10% and a solution viscosity of 100 mPa were obtained. 59 g of poly-proline solution of s. This polyamic acid was used as the polymer (C-5).

[Example 5]

4.81 g (0.0083 mol) of compound (A-3) as a tetracarboxylic dianhydride, 1.919 g (0.0084 mol) of a compound (B-1) as a diamine were dissolved in NMP 54.0 g at room temperature The reaction was carried out for 10 hours. Thus, a solid concentration of 10% and a solution viscosity of 94 mPa were obtained. 59 g of poly-proline solution of s. This polyaminic acid was used as the polymer (C-6).

[Synthesis Example 4]

4.228 g (0.00801 mol) of the compound (A-2) as a tetracarboxylic dianhydride, 1.718 g (0.00809 mol) of 4,4'-ethylenediphenylamine as a diamine was dissolved in NMP 54.0 g, and The reaction was carried out for 10 hours at room temperature. Thus, a solid concentration of 10% and a solution viscosity of 320 mPa were obtained. 59 g of poly-proline solution of s. Polylysine As the polymer (C-7).

[Embodiment 6]

4.175 g (0.0085 mol) of the compound (A-3) as a tetracarboxylic dianhydride, 1.825 g (0.0086 mol) of 4,4'-ethylenediphenylamine as a diamine was dissolved in NMP 54.0 g, and The reaction was carried out for 10 hours at room temperature. Thus, a solid concentration of 10% and a solution viscosity of 230 mPa were obtained. 59 g of a poly-proline solution of s. This polyamic acid was used as the polymer (C-8).

[Synthesis Example 7 to Synthesis Example 32]

The polymer (C-11) to the polymer (S-11) was synthesized by the same operation as in Synthesis Example 1, except that the type and amount of the tetracarboxylic dianhydride and the diamine used were changed as shown in Table 2 below. C-36).

[Synthesis Example 33]

200 g (1.0 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride, 2,2'-dimethyl-4,4'- as diamine 210 g (1.0 mol) of diaminobiphenyl dissolved in a mixed solvent of NMP 370 g and γ-butyrolactone 3,300 g, and reacted at 40 ° C for 3 hours to obtain a solid concentration of 10 wt%, The solution viscosity is 160 mPa. s polylysine solution. This polyaminic acid was used as the polymer (CR-1).

<Synthesis of polyamidomate>

[Synthesis Example 5]

70.1 g (0.153 mol) of the compound (A) as a tetracarboxylic dianhydride was added to 75 g of methanol to prepare a dicarboxylic acid diester. The obtained precipitate was collected by filtration, washed with methanol, and dried under reduced pressure to give a dicarboxylic acid diester powder. Make it available After dissolving 27.7 g (0.053 mol) of the dicarboxylic acid diester in NMP 333 g, 6.10 g (0.0565 mol) of p-phenylenediamine as a diamine was added thereto and dissolved. To this solution was added 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM, 15±2 wt%) Hydrate) 46.8 g (0.169 mol), further adding 59.8 g of NMP, and reacting at room temperature for 4 hours to obtain a polyamidate solution. Thereafter, a large amount of water was added to the obtained polyphthalate solution, and the precipitate was collected and dried to obtain a polyphthalate (polymer (C-9)).

<Synthesis of Polyimine>

[Synthesis Example 6]

a compound (A-5) represented by the above formula (a-5) and 2-(4-aminophenyl)ethylamine as a diamine as a tetracarboxylic dianhydride (relative to tetracarboxylic acid) The dianhydride was used in an amount of 1.01 times moles, dissolved in NMP, and reacted at room temperature for 6 hours. Thus, a polyaminic acid solution having a solid concentration of 15% was obtained. Then, N-methyl acridine and acetic anhydride were used in an amount of 0.25 mol per mol of tetracarboxylic dianhydride, respectively, and the dehydration ring closure was carried out at 75 ° C for 3 hours. reaction. After the dehydration ring closure, the solvent in the system was subjected to solvent replacement using a new NMP, and a solution containing 15% by weight of polyamidiamine having a ruthenium iodide ratio of 20% was obtained. This polyimine was used as the polymer (C-10).

The types and blending amounts of the tetracarboxylic dianhydride and the diamine used for the synthesis of the polymer are shown in Tables 1 and 2 below.

In Tables 1 and 2, the numerical values in parentheses in the column of tetracarboxylic dianhydride indicate the ratio (molar parts) to 100 moles of the total of the tetracarboxylic dianhydride used. The numerical values in parentheses in the column of diamine indicate the ratio (molar parts) relative to the total of 100 moles of the diamine used. The abbreviations of tetracarboxylic dianhydride and diamine have the following meanings, respectively.

<tetracarboxylic dianhydride>

A-1 to a-14; a compound represented by each of the formulae (a-1) to (a-14)

Ac-1: 4,4'-oxydiphthalic anhydride

Ac-2: 2,3,5-tricarboxydicyclopentyl acetic acid dianhydride

Ac-3: 1,2,3,4-cyclobutane tetracarboxylic dianhydride

Ac-4: 1,2,4,5-cyclohexanetetracarboxylic dianhydride

Ac-5: a compound represented by the formula (a-15)

<Diamine>

B-1, b-5, b-8~b-18: each of the formulae (b-1), (b-5), (b-8) to (b-18) Compound represented

Bc-1: p-phenylenediamine

Bc-2: 4,4'-ethylene diphenylamine

Bc-3: 2-(4-Aminophenyl)ethylamine

Bc-4: 4,4'-diaminodiphenyl ether

Bc-5: a compound represented by the formula (b4-1)

Bc-6: 2,7-diaminofluorenone

Bc-7: 3,5-diaminobenzoic acid

Bc-8: a compound represented by the formula (b3-1)

Bc-9: 2,2'-dimethyl-4,4'-diaminobiphenyl

[Embodiment 7]

<Preparation of liquid crystal alignment agent for light alignment>

NMP and butyl cellosolve (BC) were added to the solution containing the polymer (C-1) obtained in the synthesis example 1 and sufficiently stirred to prepare a solvent composition of NMP: BC = 70:30 ( A weight ratio) of a solution having a solid concentration of 3.0 wt%. This solution was filtered using a filter having a pore size of 0.45 μm to prepare a photo-aligning agent (D-1).

<Manufacture of liquid crystal display element>

A metal substrate (electrode A and electrode B) having two systems of chromium-containing crystals (electrode A and electrode B) patterned in a comb shape and having a voltage applied to the electrode A and the electrode B independently was prepared. The glass substrate and the counter-glass substrate to which the electrode is not provided are paired, and the photo-aligning agent prepared as described above is applied to the surface of the glass substrate having the electrode and the surface facing the glass substrate by using a rotator. D-1). Then, it was prebaked on a hot plate at 80 ° C for 1 minute, and then heated in an oven which was purged with nitrogen in the system at 200 ° C for 1 hour (post-baking) to form a film thickness of 0.1. Μm coating film. Then, using a Hg-Xe lamp and a Glan-Taylor prism, the surface of the coating film was irradiated with a polarized ultraviolet ray of 10,000 J/m ² containing an open line of 313 nm from the vertical direction of the substrate surface, thereby obtaining A pair of substrates of a liquid crystal alignment film.

Then, the surface of the one substrate of the pair of substrates having the liquid crystal alignment film On the outer circumference, an epoxy resin bonding agent having an alumina ball having a diameter of 3.5 μm is applied by screen printing, and the liquid crystal alignment film of the pair of substrates is faced to face the orientation of each substrate when the polarized ultraviolet ray is irradiated. In the opposite manner, the bonding was carried out by crimping, and the bonding agent was thermally hardened at 150 ° C for 1 hour. Then, the liquid crystal "MLC-7028" manufactured by Merck was filled from the liquid crystal injection port to the gap between the substrates, and then the liquid crystal injection port was sealed with an epoxy-based adhesive. Further, in order to remove the flow alignment at the time of liquid crystal injection, it was heated at 150 ° C and then slowly cooled to room temperature. Then, the polarizing plates are bonded to the outer surfaces of the substrate so that the polarizing directions thereof are orthogonal to each other and orthogonal to the direction of the projection of the optical axis of the polarized ultraviolet rays of the liquid crystal alignment film, thereby forming a liquid crystal display element. .

In addition, the liquid crystal display element was produced by the same operation as described above except that the ultraviolet irradiation amount was changed from 10,000 J/m ² to 7,000 J/m ² and 5,000 J/m ² , respectively, and the total amount of ultraviolet irradiation was different. 3 liquid crystal display elements.

<Evaluation of Liquid Crystal Display Element>

(1) Evaluation of liquid crystal alignment (sensitivity evaluation)

With respect to the three liquid crystal display elements manufactured as described above, the presence or absence of an abnormal region in the change in brightness and darkness when a voltage of 5 V was applied/released was observed by an optical microscope. The evaluation was performed in such a manner that the liquid crystal alignment property was "good" when no abnormal region was observed, and the liquid crystal alignment "bad" was observed when the abnormal region was observed. In addition, it can be said that the smaller the amount of ultraviolet irradiation when the liquid crystal alignment property is observed, the better the sensitivity of the coating film to ultraviolet rays. As a result, the liquid crystal display element having an ultraviolet irradiation amount of 5,000 J/m ² has poor liquid crystal alignment properties. However, when the ultraviolet irradiation amount is 7,000 J/m ² or 10,000 J/m ² , good liquid crystal alignment properties are exhibited.

(2) Evaluation of burning characteristics

Among the liquid crystal display elements manufactured as described above, the liquid crystal display element having an ultraviolet irradiation amount of 10,000 J/m ² was used to evaluate the baking characteristics. First, the liquid crystal display element was placed in an environment of 25 ° C and 1 atm. without applying a voltage to the electrode B, a combined voltage of an alternating voltage of 3.5 V and a direct current voltage of 5 V was applied to the electrode A for 2 hours. Shortly thereafter, a voltage of 4 V was applied to both the electrode A and the electrode B. The time from when the voltage of the alternating current of 4 V was applied to the both electrodes was measured, and the time until the difference in the light transmittance of the electrode A and the electrode B was not visually recognized was measured. When the time is less than 20 seconds, the burnt characteristics are evaluated as "show"; when the time is 20 seconds or more and less than 60 seconds, the burnt characteristics are evaluated as "excellent"; at this time When the time is 60 seconds or more and less than 100 seconds, the baking characteristics are evaluated as "good"; when the time is 100 seconds or more and less than 150 seconds, the baking characteristics are evaluated as "OK"; When the time exceeds 150 seconds, the burn-in characteristics are evaluated as "poor". As a result, the baking characteristics of the liquid crystal display element of Example 7 were "OK".

(3) Evaluation of voltage retention rate

Among the liquid crystal display elements manufactured as described above, a liquid crystal display element having an ultraviolet irradiation amount of 10,000 J/m ² was applied with a voltage of 5 V at 60 ° C with an application time of 60 μsec and a span of 167 msec. Thereafter, the voltage holding ratio after 167 milliseconds after the application was released was measured. The measuring device used "VHR-1" manufactured by Toyo Corporation (stock). The liquid crystal display element had a voltage holding ratio of 98.5%.

[Examples 8 to 14]

A photo-aligning agent (D-2) to a photo-aligning agent (D-8) were prepared and manufactured in the same manner as in the above-described Example 7, except that the types of the polymers to be used were changed as in Table 3 below. A total of three liquid crystal display elements. In addition, various evaluations of the manufactured liquid crystal display elements were performed. The evaluation results are shown in Table 3 below.

In Table 3, the numerical values in parentheses in the column of the polymer indicate the blending ratio (parts by weight) based on 100 parts by weight of the total of the polymers used in the preparation of the photoalignment agent. In addition, "1" in the column of the manufacturing method means that the coating film after post-baking is irradiated with radiation to produce a liquid crystal alignment film.

As shown in Table 3, in Examples 7 to 14, all of the ultraviolet irradiation amounts of about 10,000 J/m ² showed good liquid crystal alignment properties. In the examples 9 to 12 and the example 14, the liquid crystal alignment property was excellent even when the ultraviolet irradiation amount was about 5,000 J/m ² , and the sensitivity to ultraviolet light was excellent. Therefore, the photo-aligning agents of Examples 9 to 12 and 14 can have a small amount of light irradiation required for the liquid crystal alignment of the coating film, so that the production efficiency of the liquid crystal display element is good, which contributes to reduction in production cost. .

Further, the liquid crystal display elements of Examples 7 to 14 were less burned and showed a high voltage holding ratio of 98.5% or more. Therefore, it is understood that the liquid crystal alignment agent (D-1) to the liquid crystal alignment agent (D-8) containing the polymer (C) having the above structure (Y) in the main chain can be suitably applied to liquid crystal alignment by photoalignment method. Film formation. Further, it is understood that the liquid crystal display element having the liquid crystal alignment film formed using the liquid crystal alignment agent exhibits excellent display characteristics.

[Example 17]

A photo-aligning agent (D-11) was prepared in the same manner as in the above Example 7, except that the type of the polymer used in the preparation of the photo-aligning agent was changed to the polymer (C-9). Further, in the preparation of the photoalignment agent (D-11), a powder recovered by reprecipitation was used instead of the polymer solution. In addition, the same operation as in the above-described Example 7 was carried out, except that the photo-aligning agent (D-11) was used, and the polarized ultraviolet rays were irradiated before the prebaking and the post-baking, thereby producing ultraviolet irradiation. A total of three liquid crystal display elements are different in quantity. Further, various evaluations were carried out in the same manner as in the above-described Example 7 using the obtained liquid crystal display element. The evaluation results thereof are shown in Table 4 below.

[Embodiment 18]

The photo-aligning agent (D-1) prepared in the above Example 7 is applied onto a substrate, and then, after the prebaking and after the post-baking, the polarized ultraviolet rays are irradiated, and in addition to this, the implementation is performed In the same operation as in Example 7, a total of three liquid crystal display elements having different ultraviolet irradiation amounts were prepared. In addition, using the obtained liquid crystal display element, Various evaluations were performed in the same manner as in the above-described Example 7. The evaluation results thereof are shown in Table 4 below.

[Example 19 to Example 28, Example 30 to Example 47]

A photo-aligning agent (D-12) to a photo-aligning agent (D-21) was prepared in the same manner as in Example 7 except that the types of the polymers used were changed as in Table 4 below. Further, a total of three liquid crystal display elements were produced in the same manner as in Example 17 using the obtained photo-aligning agent (D-12) to photo-aligning agent (D-21), respectively, and were the same as in the above-described Example 7. The way to conduct various evaluations. The evaluation results thereof are shown in Table 4 below. Further, in Example 45, two kinds of polymers were used as the polymer component of the photoalignment agent.

[Example 29]

A photo-aligning agent (D-22) was prepared in the same manner as in the above Example 7, except that 8 parts by weight of an anthrone was added as a sensitizer with respect to 100 parts by weight of the polymer. Further, a total of three liquid crystal display elements were produced in the same manner as in the above-described Example 17, except that the photo-aligning agent (D-22) was used, and various evaluations of the produced liquid crystal display elements were performed. The evaluation results thereof are shown in Table 4 below.

In Table 4, the numerical values in parentheses in the column of the polymer indicate relative to the optical alignment. The compounding ratio (parts by weight) of 100 parts by weight of the total of the polymers used in the preparation of the agent. The numerical value in parentheses in the column of the additive indicates the compounding ratio (parts by weight) based on 100 parts by weight of the total of the polymer used in the preparation of the photoalignment agent. In addition, "2" in the column of the manufacturing method indicates that a liquid crystal alignment film is produced by irradiating a coating film before baking and after baking.

As shown in Table 4, in Examples 17 to 47, good liquid crystal alignment properties were exhibited at an ultraviolet irradiation amount of about 10,000 J/m ² . In Example 20, Example 21, Example 28 to Example 30, Example 34 to Example 37, Example 39, Example 46, and Example 47, even when the ultraviolet irradiation amount was set to 5,000 J When it is about /m ² , it also shows good liquid crystal alignment, and it is excellent in sensitivity to ultraviolet rays. Further, the liquid crystal display elements of Examples 17 to 47 were less burned and showed a high voltage holding ratio. Among them, the baking characteristics of Example 17, Example 27, Example 34 - Example 37, and Example 44 were especially excellent.

[Example 48]

<Preparation of liquid crystal alignment agent for light alignment>

A solution containing polylysine as the polymer (C-1) was obtained by performing the same operation as in Synthesis Example 1. The polyaminic acid solution was poured into a very excess methanol, and the obtained precipitate was washed with methanol, and then dried at 40 ° C for 15 hours under reduced pressure, thereby obtaining a poly-proline (polymer (C) -1)) powder. To the obtained polymer (C-1), N-ethyl-2-pyrrolidone (NEP) as a first solvent, diacetone alcohol (DAA) as a second solvent, and γ-butyl as a third solvent were added. Lactone (GBL), and the solvent composition is NEP:DAA:GBL=30: 40:30 (weight ratio), a solution having a solid concentration of 6.5 wt%. This solution was filtered using a filter having a pore size of 1 μm to prepare a photo-aligning agent (D-41).

<Evaluation of swelling property of printing plate>

The swellability (swellability) of the APR plate was evaluated for the photo-aligning agent (D-41) prepared in the manner described above. The APR plate is a resin plate formed by irradiating a partially cured liquid photosensitive resin with ultraviolet rays, and is generally used for a printing plate of a liquid crystal alignment film printer. When the photo-aligning agent is brought into contact with the APR plate, the APR plate is less likely to swell, indicating that the photo-aligning agent is less likely to be immersed in the APR plate during printing, and the printability is good. The evaluation of the swellability was carried out by immersing the APR plate in a photo-aligning agent (D-41) for 1 day, and measuring the change in weight of the APR plate before and after immersion. At this time, when the weight increase of the APR plate is less than 4%, the APR plate is not easily swollen and is evaluated as "good"; in the case where the weight increase of the APR plate is 4% or more and less than 6%. The evaluation was "may"; when the amount of increase was 6% or more, the APR version was easily swollen and evaluated as "poor". As a result, in the photo-aligning agent (D-41), the swelling property of the printing plate was "good".

<Printability evaluation>

With respect to the photo-aligning agent (D-41) prepared as described above, the printability (continuous printability) at the time of continuous printing on the substrate was evaluated. The evaluation was carried out in the following manner. First, using a liquid crystal alignment film printing machine (manufactured by Japan Photo Printing Co., Ltd., Angstromer form "S40L-532"), the amount of the liquid crystal alignment agent applied to the anilox roll is 20 drops (about 0.2 g). Next, the prepared liquid crystal alignment agent (D-41) is coated on a transparent substrate of a glass substrate with a transparent electrode including an ITO film. On the pole. The coating on the substrate was carried out 20 times using a new substrate at intervals of 1 minute.

Then, the photo-aligning agent (D-41) was dispensed onto the anilox roller (one-way) at intervals of 1 minute, and the operation of bringing the anilox roller into contact with the printing plate a total of 10 times each time (hereinafter, referred to as Dry operation) (Printing on the glass substrate is not performed during this period). In addition, this dry operation is an operation for attempting to perform printing of the photo-aligning agent (D-41) under severe conditions.

After 10 empty runs, the glass substrate was used for official printing. In the main printing, after the idling operation, five substrates were placed at intervals of 30 seconds, and each substrate coated with the photo-aligning agent (D-41) was heated (prebaked) for one minute at 80 ° C to remove the solvent. Thereafter, heating was carried out at 200 ° C for 10 minutes (post-baking) to form a coating film having a film thickness of about 80 nm. The printability was evaluated by observing the coating film with a microscope having a magnification of 20 times. The evaluation was carried out in such a manner that the precipitation of the polymer was not observed from the first official printing after the dry operation, and the printing property was "good"; the polymerization was observed in the first official printing after the dry operation. In the case where the precipitation of the polymer was not observed during the period of the fifth printing, the printing property was "may"; and the precipitation of the polymer was observed even after the fifth printing was repeated. It is "bad" for printability. In the experiment, it is understood that when the liquid crystal alignment agent having good printability is used, the precipitation of the polymer is favored (disappeared) while the substrate is continuously supplied. As a result, the printability when the number of times of dry operation was 10 was "good".

Furthermore, the number of times of dry operation is changed to 15 times, 20 times, 25 times, Printability was evaluated in the same manner as described above. As a result, the printability when the number of empty runs was 25 was "may", and when it was 15 times and 20 times, the printability was "good".

[Example 49 to Example 63]

A photo-aligning agent (D-42) to a photo-aligning agent (D-56) was prepared in the same manner as in Example 48 except that the polymer and solvent used in the preparation of the photo-aligning agent were changed as shown in Table 5 below. . Further, using these photo-aligning agents (D-42) to photo-aligning agents (D-56) and the photo-aligning agents (D-1) prepared in the above-mentioned Example 18, Example 20, Example 36, and Example 47, respectively. The optical alignment agent (D-13), the optical alignment agent (D-29), and the optical alignment agent (D-40) were evaluated for the swellability and printability of the printing plate in the same manner as in Example 48. Their results are shown in Table 5 below.

In Table 5, the abbreviations of the solvent compositions are respectively the following meanings.

(1st solvent)

a: N-ethyl-2-pyrrolidone (NEP)

b: N-pentyl-2-pyrrolidone (NPP)

c: 1,3-dimethyl-2-imidazolidinone (DMI)

(second solvent)

d: propylene glycol diacetate (PGDAc)

e: diacetone alcohol (DAA)

f: diethylene glycol diethyl ether (DEDG)

g: diisoamyl ether (DIPE)

(third solvent)

h: γ-butyrolactone (GBL)

i: propylene carbonate (PC)

j: N-methyl-2-pyrrolidone (NMP)

m: butyl cellosolve (BC)

As shown in Table 5, the photo-aligning agent of the Example did not easily swell the APR plate, and the printability was also good. Among them, in Examples 48 to 63 in which the first solvent and the second solvent were used, the APR plate was less likely to swell.

Claims (12)

A method for producing a liquid crystal alignment film, comprising: a film forming step of coating a photoalignment liquid crystal alignment agent containing a polymer (C) on a substrate to form a coating film, wherein the polymer (C) is selected from the group consisting of At least one of the group consisting of lysine, polyphthalate, and polyimine, and having a structure (Y) represented by the following formula (1) in the main chain, the polymer (C) Is a polymer obtained by reacting tetracarboxylic dianhydride with one or more diamines containing a diamine having the above structure (Y), and the diamine having the structure (Y) includes a formula At least one of (b-1), formula (b-5), formula (b-8) to formula (b-18); and a light irradiation step of irradiating the coating film with light to form a liquid crystal alignment film ; (in the formula (1), X ¹ is a sulfur atom or an oxygen atom; "*" represents a bonding bond; wherein at least one of the two "*" is bonded to the aromatic ring); The method for producing a liquid crystal alignment film according to claim 1, wherein the film forming step includes a prebaking step of preheating the photoalignment liquid crystal alignment agent coated on the substrate, and The pre-baked coating film is further subjected to a post-baking step of heating, and the light-irradiating step irradiates the coating film before the pre-baking step and the post-baking step with light. The method for producing a liquid crystal alignment film according to claim 1, wherein the film forming step includes a prebaking step of preheating the photoalignment liquid crystal alignment agent coated on the substrate, and The pre-baked coating film is further subjected to a post-baking step of heating, and the light irradiation step irradiates the coating film after the post-baking step with light. The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the polymer (C) is a tetracarboxylic dianhydride containing the structure (Y). A polymer obtained by reacting one or two or more kinds of tetracarboxylic dianhydride with one or two or more kinds of diamines containing a diamine having the above structure (Y). The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the polymer (C) further has a structure represented by the following formula (3) in the main chain. (In the formula (3), k and m are each independently 0 or 1, l is an integer of 2 to 5, n is an integer of 1 to 4; "*" represents a bonding key). The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the polymer (C) further has a nitrogen-containing hetero ring in the main chain. The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the polymer (C) is a tetracarboxylic dianhydride and a diamine having a carboxyl group. Or a polymer obtained by reacting two or more kinds of diamines. The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the liquid alignment alignment agent further comprises a photosensitizer. The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the polymer (C) further has a structure capable of exhibiting a light sensitizing function, and the visible light increase The structure of the sensory function includes a benzophenone structure or a quinone structure. The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the liquid alignment alignment agent contains the polymer (C) and a solvent, and the solvent contains At least one of a group consisting of a compound represented by the following formula (4), a compound represented by the following formula (5), and 1,3-dimethyl-2-imidazolidinone, (In the formula (4), R ¹¹ is a monovalent hydrocarbon group having 2 to 5 carbon atoms or a monovalent group having "-O-" between carbon-carbon bonds in the hydrocarbon group) (In the formula (5), R ¹² and R ¹³ are each independently a hydrogen atom, a monovalent hydrocarbon group having 1 to 6 carbon atoms, or a "-O-" group in a carbon-carbon bond in the hydrocarbon group. A monovalent group, R ¹² and R ¹³ may be bonded to each other to form a ring structure; and R ¹⁴ is an alkyl group having 1 to 6 carbon atoms). The method for producing a liquid crystal alignment film according to any one of claims 1 to 3, wherein the liquid alignment alignment agent contains the polymer (C) and a solvent, and the solvent contains At least one of a group consisting of a compound represented by the following formula (6), a compound represented by the following formula (7), and a compound represented by the following formula (8), (In the formula (6), R ¹⁵ and R ¹⁷ are each independently a monovalent hydrocarbon group having 1 to 3 carbon atoms, and R ¹⁶ is an alkanediyl group having 2 to 5 carbon atoms) R ¹⁸ -OR ¹⁸ (7) (In the formula (7), R ¹⁸ is a monovalent oxy group containing one "-O-" between carbon-carbon bonds of a linear or branched alkyl group having 3 to 5 carbon atoms, or a branched alkyl group having a carbon number of 3 to 5) (In the formula (8), X ⁵ is -C(OH)R ^a - (wherein R ^a is an alkyl group having 1 or 2 carbon atoms), -CO- or -COO-* (where * represents R key ^{19 is} bonded), R ¹⁹ is a carbon number of 1 - 4 alkyl group). A liquid crystal display element comprising a liquid crystal alignment film produced by the production method according to any one of claims 1 to 11.