JP6410026B2 - Hydrogen bond cured film forming composition having photo-alignment property - Google Patents

Description

  In recent years, in the field of displays such as a television using a liquid crystal panel, development of a 3D display capable of enjoying 3D images has been promoted as an effort toward high performance. In the 3D display, for example, a right-eye image is visually recognized by an observer's right eye, and a left-eye image is visually recognized by an observer's left eye, whereby a stereoscopic image can be displayed.

There are various 3D display methods for displaying 3D images, and lenticular lens methods, parallax barrier methods, and the like are known as methods that do not require dedicated glasses.
And as one of the display systems in which an observer wears glasses and observes a 3D image, a circularly polarized glasses system or the like is known (see, for example, Patent Document 1).

  In the case of a circularly polarized glasses type 3D display, a retardation material is usually disposed on a display element that forms an image, such as a liquid crystal panel. In this retardation material, a plurality of two kinds of retardation regions having different retardation characteristics are regularly arranged, and a patterned retardation material is formed. Hereinafter, in the present specification, a retardation material patterned so as to arrange a plurality of retardation regions having different retardation characteristics is referred to as a patterned retardation material.

  For example, as disclosed in Patent Document 2, the patterned retardation material can be produced by optically patterning a retardation material made of a polymerizable liquid crystal. Optical patterning of a retardation material made of a polymerizable liquid crystal utilizes a photo-alignment technique known for forming an alignment material for a liquid crystal panel. That is, a coating film made of a photo-alignment material is provided on a substrate, and two types of polarized light having different polarization directions are irradiated on the coating film. Then, a photo-alignment film is obtained as an alignment material in which two types of liquid crystal alignment regions having different liquid crystal alignment control directions are formed. A solution-like retardation material containing a polymerizable liquid crystal is applied on the photo-alignment film to realize the alignment of the polymerizable liquid crystal. Thereafter, the aligned polymerizable liquid crystal is cured to form a patterned retardation material.

  In the formation of alignment materials using the photo-alignment technology of liquid crystal panels, acrylic resins and polyimide resins having photodimerization sites such as cinnamoyl groups and chalcone groups in the side chain are known as usable photo-alignment materials. . These resins have been reported to exhibit the ability to control the alignment of liquid crystals (hereinafter also referred to as liquid crystal alignment) by irradiation with polarized UV (see Patent Documents 3 to 5).

Japanese Patent Laid-Open No. 10-232365 JP 2005-49865 A Japanese Patent No. 3611342 JP 2009-058584 A JP-T-2001-517719

As described above, the patterned retardation material is configured by laminating a cured polymerizable liquid crystal layer on a photo-alignment film that is an alignment material. And the patterned phase difference material which has such a laminated structure can be used for the structure of 3D display with the laminated state.
Therefore, it is necessary to develop a cured film that can be used as an alignment material having both excellent liquid crystal alignment properties and light transmission properties, and a cured film forming composition for forming the cured film.

  The object of the present invention has been made based on the above findings and examination results. That is, an object of the present invention is to provide a cured film forming composition suitable for forming a cured film having excellent liquid crystal orientation and light transmission characteristics. In particular, an object of the present invention is to provide a cured film forming composition that forms a cured film that exhibits excellent liquid crystal alignment and light transmission when a polymerizable liquid crystal layer is disposed thereon as an alignment material. Is to provide things.

  An object of the present invention is to provide an alignment material having excellent liquid crystal alignment properties and light transmission characteristics.

  An object of the present invention is to provide a retardation material capable of high-precision optical patterning.

  Other objects and advantages of the present invention will become apparent from the following description.

  As a result of intensive studies to solve the above problems, the present inventors have found the present invention. That is, the present invention is as follows.

[1] As a component (A), a repeating unit having a photoalignable group, and a polymer and a solvent having one or more groups selected from a CONH ₂ group and a COOH group only in a repeating unit other than the repeating unit And a hydrogen-bonded cured film-forming composition having photo-alignment characteristics, characterized by satisfying the following (I):
(I): When one or more groups selected from the CONH ₂ group and the COOH group of the component (A) are only COOH groups, a urethane bond is further present in the side chain of the component (A), or (B And a polymer having at least one selected from a CONH ₂ group and a urethane bond in the repeating unit as an essential component.
[2] The cured film-forming composition as described in 1 above, which does not contain a crosslinking agent that reacts with any of CONH ₂ groups, COOH groups, and urethane bonds.
[3] The cured film house-forming composition as described in 1 or 2 above, wherein the urethane bond is present in the side chain having a photoreactive group.
[4] The hydrogen bond cured film forming composition as described in any one of 1 to 3 above, wherein the component (A) is an acrylic polymer.
[5] The hydrogen bond cured film forming composition as described in any one of 1 to 3 above, wherein the photo-alignable group of the component (A) is a functional group having a structure capable of photodimerization or photoisomerization.
[6] The hydrogen bond cured film forming composition as described in any one of 1 to 4 above, wherein the photoalignable group of the component (A) is a cinnamoyl group.
[7] The hydrogen bond cured film forming composition as described in any one of 1 to 4 above, wherein the photoalignable group of the component (A) is a group having an azobenzene structure.
[8] The hydrogen bond cured film forming composition according to any one of 1 to 7 above, which contains a solvent capable of forming a hydrogen bond with the component (A) and / or the component (B).
[9] The hydrogen-bonded cured film-forming composition as described in any one of 2 to 8 above, wherein the proportion of the component (A) is 5 to 100% by mass based on the total amount of the components (A) and (B) object.
[10] The component (A) according to any one of 1 to 9 above, wherein the proportion of the unit structure having a photoalignable group in the polymer is 50 to 90% by mass based on the total mass of the polymer. A hydrogen-bonded cured film-forming composition.
[11] An alignment material obtained by using the hydrogen bond cured film forming composition according to any one of 1 to 10 above.
[12] A retardation material comprising a cured film obtained from the hydrogen-bonded cured film-forming composition according to any one of 1 to 10 above.

  According to the 1st aspect of this invention, the cured film formation composition suitable for formation of the cured film which has the outstanding liquid crystal aligning property and light transmittance can be provided.

  According to the second aspect of the present invention, it is possible to provide an alignment material excellent in liquid crystal alignment and light transmittance.

  According to the third aspect of the present invention, it is possible to provide a retardation material capable of high-precision optical patterning.

The present invention is characterized in that the performance is improved by using the curable resin composition, that is, the (A) component, which is a repeating unit having a photoalignment group, and a repeating unit other than the repeating unit. When the polymer having a group selected from a CONH ₂ group and a COOH group only in the unit and the component (A) is a polymer having a photo-alignment group and a COOH group, the side chain of the photopolymer is included. A cured film having photo-alignment properties, which further contains, as an essential component, a polymer having at least one selected from a CONH ₂ group and a urethane bond in the repeating unit, which is a component (B) in which a urethane bond exists. A forming composition. Furthermore, in addition to (A) component and (B) component, it is a polyester composition for thermosetting film formation which can also contain a sensitizer as (C) component.
Hereinafter, details of each component will be described.

[Component (A) and Component (B)]
In the composition of the present invention, the component (A) is a polymer having a repeating unit having a photoalignment group and a group selected from a CONH ₂ group and a COOH group only in a repeating unit other than the repeating unit, In the case where one or more groups selected from the CONH ₂ group and the COOH group of the component (A) are only COOH groups, a urethane bond is further present in the side chain of the component (A), or the component (B) A polymer having at least one selected from a CONH ₂ group and a urethane bond in a repeating unit is further contained as an essential component. Here, the polymer as the component (B) may or may not have a photoreactive group.

  As the component (A), an acrylic polymer is preferable. In the present invention, the acrylic copolymer refers to a copolymer obtained by polymerizing a monomer having an unsaturated double bond such as (meth) acrylic acid, (meth) acrylic acid ester, (meth) acrylamide, and styrene. .

  The acrylic polymer of the component (A) and the component (B) (hereinafter also referred to as a specific polymer) may be an acrylic polymer having such a structure, and the main chain skeleton of the polymer constituting the acrylic polymer and It does not specifically limit about the kind of side chain.

  In the component (A) and the component (B), the photoalignable group is preferably a group having a site selected from a photodimerization site and a photoisomerization site. Examples of the photodimerization site include a cinnamoyl group, a chalcone group, a coumarin group, and an anthracene group. Of these, a cinnamoyl group is preferred because of its high transparency in the visible light region and high photodimerization reactivity. The photoisomerization site is a site where the cis form and trans form are changed by light irradiation, and specific examples thereof include azobenzene, stilbene and the like. Of these, azobenzene groups are preferred because of their high reactivity. A more preferred cinnamoyl group is a structure represented by the following formula [1] or [2]. Further, preferred azobenzene and stilbene have a structure represented by the following formula [3].

In Formula [1] and Formula [2], X ¹ represents an alkyl group having 1 to 18 carbon atoms, a phenyl group, or a biphenyl group. In that case, the hydrogen atom of a phenyl group and a biphenyl group may be substituted by the group chosen from a halogen atom, an alkoxy group, and a cyano group. X ² represents a hydrogen atom, a cyano group, an alkyl group having 1 to 18 carbon atoms, a phenyl group, a biphenyl group, or a cyclohexyl group. In this case, the alkyl group having 1 to 18 carbon atoms, the phenyl group, the biphenyl group, and the cyclohexyl group may be bonded via a covalent bond, an ether bond, an ester bond, a carbonyl, an amide bond, a urethane bond, or a urea bond. . Moreover, the hydrogen atom of a phenyl group and a biphenyl group may be substituted by any of a halogen atom, an alkoxy group, and a cyano group.

Y ¹ and Y ² in Formula [3] each independently represent N (nitrogen atom) or CH. X ² represents a hydrogen atom, a cyano group, an alkyl group having 1 to 18 carbon atoms, a phenyl group, a biphenyl group, or a cyclohexyl group. In this case, the alkyl group having 1 to 18 carbon atoms, the phenyl group, the biphenyl group, and the cyclohexyl group may be bonded through a covalent bond, an ether bond, a carbonyl, an ester bond, an amide bond, a urethane bond, or a urea bond. .

  In the above formula [1] and formula [2], A represents any one of formula [A1], formula [A2], formula [A3], formula [A4], formula [A5], and formula [A6].

In the above formula [A1], formula [A2], formula [A3], formula [A4], formula [A5] and formula [A6], R ³¹ , R ³² , R ³³ , R ³⁴ , R ³⁵ , R ³⁶ , R ³⁷ and R ³⁸ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a trifluoromethyl group, or a cyano group.

  As a method for introducing a photoalignable group into the component (A) and / or the component (B), as described above, the acrylic copolymer having a photodimerization site and a thermal crosslinking site in the side chain of the component (A) is used. Examples of the synthesis method include a method of copolymerizing a monomer having a photodimerization site and a monomer having a thermal crosslinking site.

  Examples of the monomer having a photodimerization group include monomers having a cinnamoyl group, a chalcone group, a coumarin group, an anthracene group, and the like. Among these, a monomer having a cinnamoyl group is particularly preferable because of its high transparency in the visible light region and high photodimerization reactivity.

  As a monomer which has a photoisomerization group, the monomer which has an azobenzene group, a stilbene group etc. is mentioned, for example.

  Among these, a monomer having a cinnamoyl group having a structure represented by the above formula [1] or [2] is more preferable. Specific examples of such a monomer are monomers represented by the following formula [3] or formula [4].

Here, X ¹ , X ² and A represent the meanings defined in the formula [1] and formula [2]. X ³ and X ⁵ each independently represent a single bond, a divalent group selected from the group consisting of alkylene having 1 to 20 carbons, cycloalkylene having 3 to 10 carbons and aromatic rings, or this group In this case, the plurality of groups are bonded with a bonding group selected from a single bond, an ester bond, an ether bond, an amide bond, a urethane bond and a urea bond. It may be. Here, the alkylene group having 1 to 20 carbon atoms may be branched or linear, and may contain a C═C double bond or a triple bond. X ⁴ and X ⁶ represent a polymerizable group. Specific examples of the polymerizable group include acryloyl group, methacryloyl group, styrene group, maleimide group, acrylamide group, and methacrylamide group.

In the component (A) and the component (B), monomers that give a repeating unit having a COOH group (carboxyl group) include acrylic acid, methacrylic acid, crotonic acid, mono- (2- (acryloyloxy) ethyl) phthalate, mono -(2- (methacryloyloxy) ethyl) phthalate, N- (carboxyphenyl) maleimide, N- (carboxyphenyl) methacrylamide, N- (carboxyphenyl) acrylamide, p-vinylbenzoic acid, and the like.

In the component (A) and the component (B), examples of the monomer that gives a repeating unit having a CONH ₂ group (amide group) include acrylamide, methacrylamide, and p-vinylbenzoic acid amide.

  As another method for introducing a photo-alignable group into the component (A), an acrylic polymer having a specific functional group is generated in advance by a polymerization method such as radical polymerization, and then the specific functional group and the photo-alignment are prepared. By reacting a compound having a reactive group (hereinafter referred to as a specific compound) to generate a specific side chain, a photoreactive group can be introduced into the polymer as the component (A). The same applies when it is desired to introduce a photo-alignment group into the component (B).

  Here, the specific functional group refers to a functional group such as a carboxyl group, a glycidyl group, a hydroxy group, an amino group having active hydrogen, a phenolic hydroxy group or an isocyanate group, or a plurality of types of functional groups selected from these functional groups. .

  In the reaction for generating the specific side chain described above, the preferred combination of the specific functional group and the functional group of the specific compound that is involved in the reaction is a carboxyl group and an epoxy group, a hydroxy group and an isocyanate group, or a phenolic group. A hydroxy group and an epoxy group, a carboxyl group and an isocyanate group, an amino group and an isocyanate group, or a hydroxy group and an acid chloride. Furthermore, a more preferable combination is a carboxyl group and glycidyl methacrylate, or a hydroxy group and isocyanate ethyl methacrylate.

  In the reaction for generating the specific side chain described above, the polymer having the specific functional group is a monomer having a functional group (specific functional group) for reacting with the specific compound in addition to the specific monomer X1, that is, a carboxyl group. , A copolymer obtained by using, as an essential component, a monomer having a glycidyl group, a hydroxy group, an amino group having active hydrogen, a phenolic hydroxy group or an isocyanate group (hereinafter also referred to as a specific monomer X2), and its number average The molecular weight is 2,000 to 25,000. Here, the monomer having the specific functional group used for the polymerization may be used alone, or a plurality of types may be used in combination as long as the combination does not react during the polymerization.

  The specific example of the monomer required in order to obtain the polymer which has a specific functional group, ie, specific monomer X2, is given to the following. However, it is not limited to these.

  Examples of the monomer having a carboxyl group include acrylic acid, methacrylic acid, crotonic acid, mono- (2- (acryloyloxy) ethyl) phthalate, mono- (2- (methacryloyloxy) ethyl) phthalate, and N- (carboxyphenyl). ) Maleimide, N- (carboxyphenyl) methacrylamide and N- (carboxyphenyl) acrylamide, p-vinylbenzoic acid and the like.

  Examples of the monomer having a glycidyl group include glycidyl methacrylate, glycidyl acrylate, allyl glycidyl ether, 3-ethenyl-7-oxabicyclo [4.1.0] heptane, 1,2-epoxy-5-hexene and 1,7. -Octadiene monoepoxide and the like.

  Examples of the monomer having a hydroxy group include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, 2,3- Dihydroxypropyl acrylate, 2,3-dihydroxypropyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, caprolactone 2- (acryloyloxy) ethyl ester, caprolactone 2- (methacryloyloxy) ethyl ester, poly (ethylene glycol) ethyl ether acrylate, poly (Ethylene glycol) ethyl ether methacrylate, 5-acryloyl Shi-6-hydroxy-norbornene-2-carboxylic-6-lactone and 5-methacryloyloxy such acryloyloxy-6-hydroxy-norbornene-2-carboxylic-6-lactone.

  Examples of the monomer having an amino group include 2-aminoethyl acrylate and 2-aminomethyl methacrylate.

  Examples of the monomer having a phenolic hydroxy group include hydroxystyrene, N- (hydroxyphenyl) acrylamide, N- (hydroxyphenyl) methacrylamide and N- (hydroxyphenyl) maleimide.

  As a monomer which has an isocyanate group, acryloyl ethyl isocyanate, methacryloyl ethyl isocyanate, m-tetramethyl xylene isocyanate, etc. are mentioned, for example.

In the side chain thus obtained, specific examples of X ³ and X ⁵ include the following formulas (A-1) to (A-11).

  When it is desired to leave the specific functional group, after producing a polymer having the specific functional group, a compound having a photoreactive group having a smaller number of moles than the specific functional group may be reacted.

The amount of the monomer having a photoreactive group used to obtain the specific copolymer and the monomer having a group selected from a CONH ₂ group and a COOH group is 40 to 90% by mass of the monomer having a photoreactive group, The monomer having a group selected from a CONH ₂ group and a COOH group is preferably 10 to 60% by mass. By setting the content of the monomer having a photoreactive group to 40% by mass or more, high sensitivity and good liquid crystal alignment can be imparted. On the other hand, when the content of the monomer having a group selected from CONH ₂ group and COOH is 10% by mass or more, sufficient curability due to hydrogen bonding can be imparted, and high-sensitivity and good liquid crystal orientation is maintained. can do.

In the present invention, a monomer that can be copolymerized with a monomer having a photoreactive group, a group selected from a CONH ₂ group and a COOH group (hereinafter also referred to as a specific functional group) when obtaining a specific copolymer. (Hereinafter also referred to as a monomer having a non-reactive functional group) can be used in combination.
Specific examples of such monomers include acrylic ester compounds, methacrylic ester compounds, maleimide compounds, N-substituted acrylamide compounds, acrylonitrile, maleic anhydride, styrene compounds and vinyl compounds.
Hereinafter, although the specific example of the said monomer is given, it is not limited to these.

Examples of the acrylic ester compound include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthryl acrylate, anthryl methyl acrylate, phenyl acrylate, glycidyl acrylate, 2,2,2-trifluoroethyl acrylate. Tert-butyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, 2-aminoethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2 -Methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate Rate, 8-methyl-8-tricyclodecyl acrylate, and the like 8-ethyl-8-tricyclodecyl acrylate.

  Examples of the methacrylic acid ester compound include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthryl methacrylate, anthryl methyl methacrylate, phenyl methacrylate, glycidyl methacrylate, 2,2,2-trifluoroethyl methacrylate. Tert-butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, 2-aminomethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2 -Methyl-2-adamantyl methacrylate Over DOO, .gamma.-butyrolactone methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, and, 8-ethyl-8-tricyclodecyl methacrylate.

  Examples of the vinyl compound include methyl vinyl ether, benzyl vinyl ether, vinyl naphthalene, vinyl carbazole, allyl glycidyl ether, 3-ethenyl-7-oxabicyclo [4.1.0] heptane, 1,2-epoxy-5-hexene. And 1,7-octadiene monoepoxide.

  Examples of the styrene compound include styrene, methylstyrene, chlorostyrene, bromostyrene, and the like.

  Examples of the maleimide compound include maleimide, N-methylmaleimide, N-phenylmaleimide, and N-cyclohexylmaleimide.

The method for obtaining the specific copolymer used in the present invention is not particularly limited. For example, in a solvent in which a monomer having a specific functional group, a monomer having a non-reactive functional group, and a polymerization initiator coexist if desired, 50 It is obtained by carrying out a polymerization reaction at a temperature of from 110 to 110 ° C. In that case, the solvent used will not be specifically limited if it dissolves the monomer which has a specific functional group, the monomer which has a non-reactive functional group used depending on necessity, a polymerization initiator, etc. Specific examples include solvents described in Solvents described below.
The specific copolymer thus obtained is usually in the form of a solution dissolved in a solvent.

In addition, the solution of the specific copolymer obtained as described above is re-precipitated by stirring with stirring such as diethyl ether or water, and the generated precipitate is filtered and washed, and then under normal pressure or reduced pressure. Thus, the powder of the specific copolymer can be obtained by drying at room temperature or by heating. By such an operation, the polymerization initiator and unreacted monomer coexisting with the specific copolymer can be removed, and as a result, a purified powder of the specific copolymer can be obtained. If sufficient purification cannot be achieved by a single operation, the obtained powder may be redissolved in a solvent and the above operation may be repeated.
In the present invention, the powder of the specific copolymer may be used as it is, or the powder may be redissolved in a solvent described later and used as a solution.

The acrylic copolymer of component (A) and component (B) preferably has a weight average molecular weight of 3,000 to 200,000. When the weight average molecular weight is over 200,000, the solubility in the solvent is lowered and the handling property is lowered. On the other hand, when the weight average molecular weight is less than 3,000, the liquid crystal orientation is too small. May decrease.

The component (A) is a polymer having a photoalignment group and a COOH group, and the polymer (B) contains a polymer having at least one selected from a CONH ₂ group and a urethane bond in the repeating unit. In this case, the content of the component (B) is 3 to 10000 parts by mass, more preferably 5 to 2000 parts by mass, per 100 parts by mass of the component (A).

  In the present invention, the acrylic copolymer of the component (A) and the component (B) may be a mixture of a plurality of types of specific copolymers.

<(C) component>
In the present invention, a sensitizer may be contained as the component (C). This component (C) is effective in promoting the photodimerization reaction after forming the thermosetting film of the present invention.

  (C) As a sensitizer of a component, derivatives, such as a benzophenone, anthracene, anthraquinone, thioxanthone, are mentioned. Of these, N, N-diethylaminobenzophenone, which is a benzophenone derivative, is particularly preferred.

  These sensitizers are not particularly limited to those described above. These can be used alone or in combination of two or more compounds.

  In the present invention, the use ratio of the sensitizer of the component (C) is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 10 parts by mass with respect to 100 parts by mass of the component (A). It is. If this ratio is too small, the effect as a sensitizer may not be sufficiently obtained. If it is too large, the transmittance may be lowered or the coating film may be roughened.

<Solvent>
The thermosetting film-forming composition having photo-alignment property of the present invention is often used in a solution state dissolved in a solvent. The solvent used in that case is a solvent that dissolves the component (A) and the component (B) and, if necessary, the component (C) and / or other additives described later, and has such a dissolving ability. If so, the type and structure thereof are not particularly limited.

Specific examples of the solvent include, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether Acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, 3-methyl-2-pentanone, 2-pentanone, 2-heptanone, γ-butyrolactone, ethyl 2-hydroxypropionate , Ethyl 2-hydroxy-2-methylpropionate, eth Ethyl ethyl acetate, hydroxy hydroxyethyl, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, Examples include ethyl pyruvate, ethyl acetate, butyl acetate, isobutyl acetate, ethyl lactate, butyl lactate, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylpyrrolidone, and cyclopentyl methyl ether.

  These solvents can be used singly or in combination of two or more. Among these solvents, propylene glycol monomethyl ether, cyclohexanone, 2-heptanone, propylene glycol propyl ether, ethyl lactate, butyl lactate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, 3- Methyl ethoxypropionate is more preferred because it has good polymer solubility and film-forming properties and high safety.

  In addition, a solvent that can form a hydrogen bond with the component (A) and / or the component (B) can also be used. By using such a solvent, it is possible to prevent the component (A) and / or the component (B) from aggregating and precipitating in the solvent, and to improve the stability of the solution.

Specific examples of the solvent capable of forming a hydrogen bond with the component (A) and the component (B) include, for example, basic solvents such as triethylamine, tripropylamine, tributylamine and pyridine, acidic solvents such as formic acid and acetic acid, Neutral solvents such as water, ethanol, acetonitrile and the like.

<Other additives>
Furthermore, the cured film-forming composition having photo-alignment property of the present invention is a silane coupling agent, a surfactant, a rheology modifier, a pigment, a dye, a storage as long as the effects of the present invention are not impaired. Stabilizers, antifoaming agents, antioxidants and the like can be contained. In addition, even if it contains the crosslinking agent, it does not need to contain. Even when the crosslinking agent is not contained, the present invention is effective.

<A cured film forming composition having photo-alignment>
The cured film forming composition having photo-alignment property of the present invention contains an acrylic copolymer of the component (A) and / or the component (B) and, if desired, a sensitizer of the component (C), and further other additives. It is a composition which can contain 1 or more types. Usually, they are often used as a solution in which they are dissolved in a solvent.

Especially, the preferable example of the cured film formation composition which has the photo-alignment property of this invention is as follows.
[1]: Hydrogen bond curing having photo-alignment property, which contains a repeating unit having a photo-alignment group as a component (A), a polymer having a CONH ₂ group only in a repeating unit other than the repeating unit, and a solvent. Film-forming composition.
[2]: Photo-alignment comprising, as component (A), a repeating unit having a photo-alignment group, a polymer having a COOH group only in a repeating unit other than the repeating unit, and further having a urethane bond and a solvent. Composition for forming a hydrogen bond cured film.
[3]: 3 to 10,000 based on (A) a repeating unit having a photoalignable group, a polymer having a COOH group only in a repeating unit other than the repeating unit, and 100 parts by mass of component (A) A cured film-forming composition having photo-alignment properties containing a component (B) of a part by mass and a solvent.

The blending ratio, preparation method, etc. in the case of using the cured film forming composition having photo-alignment property of the present invention as a solution will be described in detail below.
The ratio of the solid content in the cured film forming composition having photo-alignment property of the present invention is not particularly limited as long as each component is uniformly dissolved in the solvent, but is 1 to 80% by mass, The amount is preferably 2 to 60% by mass, more preferably 3 to 40% by mass. Here, solid content means what remove | excluded the solvent from all the components of the cured film formation composition which has photo-orientation property.

  Although the preparation method of the cured film formation composition which has the photo-orientation property of this invention is not specifically limited, As the preparation method, (A) component is melt | dissolved in a solvent, for example, (B) component, Can be obtained by mixing the component (C) at a predetermined ratio to obtain a uniform solution, or at a suitable stage of the preparation method, and further adding other additives as necessary.

  In preparing the thermosetting film-forming composition having photo-alignment property of the present invention, a solution of a specific copolymer obtained by a polymerization reaction in a solvent can be used as it is. In this case, when the solution of the specific copolymer, that is, the solution of the component (A) is mixed with the component (B), the component (C), etc. as described above to obtain a uniform solution, a solvent is further added for the purpose of concentration adjustment May be added. At this time, the solvent used in the production process of the specific copolymer and the solvent used for concentration adjustment when preparing the thermosetting film-forming composition having photo-alignment may be the same or different. Also good.

  Thus, the prepared solution of the thermosetting film-forming composition having photo-alignment properties is preferably used after being filtered using a filter having a pore diameter of about 0.2 μm.

<Coating film, cured film and liquid crystal alignment layer>
The solution of the thermosetting film-forming composition having photo-alignment which is one embodiment of the present invention is coated with a substrate (for example, a silicon / silicon dioxide-coated substrate, a silicon nitride substrate, a metal such as aluminum, molybdenum, or chromium). Substrate, glass substrate, quartz substrate, ITO substrate, etc.) and film (for example, resin film such as triacetyl cellulose film, polyester film, acrylic film) etc., bar coating, spin coating, flow coating, roll coating, Apply by slit coating, spin coating following slit, inkjet coating, printing, etc., and then dry (bake) with a hot plate or oven, etc., so that (A) components or (A) component and (B) A coating film in which hydrogen bonds are formed between the components can be formed.

  As the baking conditions, for example, a heating temperature and a heating time appropriately selected from the range of a temperature of 50 ° C. to 160 ° C. and a time of 0.3 to 60 minutes are employed. The heating temperature and heating time are preferably 80 to 140 ° C. and 0.5 to 10 minutes.

  The film thickness of the coating film is, for example, 0.05 μm to 5 μm, and can be appropriately selected in consideration of the level difference of the substrate to be used and optical and electrical properties.

The cured film thus formed can function as a liquid crystal material alignment layer, that is, a layer for aligning a liquid crystal compound by performing modified UV irradiation.
As an irradiation method of polarized UV, ultraviolet light having a wavelength of 150 to 450 nm is usually used, and irradiation is performed by irradiating linearly polarized light from a vertical or oblique direction at room temperature or in a heated state.

After coating the retardation material on the liquid crystal alignment layer formed in this manner, the retardation material is photocured in a liquid crystal state by heating to form a layer having optical anisotropy.
As the retardation material, for example, a liquid crystal monomer having a polymerizable group or a composition containing the same is used. And when the base material which forms a liquid crystal aligning layer is a film, it is useful as an optically anisotropic film. Such retardation materials include those having alignment properties such as horizontal alignment, cholesteric alignment, vertical alignment, hybrid alignment, and the like, and can be selectively used depending on the required phase difference.

  Further, when producing a patterned retardation material used for a 3D display, a line and space pattern mask is applied to the cured film formed by the above-described method from the retardation material forming resin composition of the present embodiment. For example, the polarized UV exposure is performed in a +45 degree direction from a predetermined reference, and then the polarized UV is exposed in a -45 degree direction after removing the mask. An alignment material in which regions are formed is obtained. Thereafter, after applying a retardation material made of a polymerizable liquid crystal solution, the retardation material is brought into a liquid crystal state by being heated to the phase transition temperature of the liquid crystal, and is aligned on the alignment material. Then, the retardation material in an oriented state is cured as it is, and a patterned retardation material in which a plurality of two types of retardation regions having different retardation characteristics are regularly arranged can be obtained.

  Further, after bonding the two substrates having the liquid crystal alignment layer formed as described above so that the liquid crystal alignment layer faces each other through a spacer, liquid crystal is injected between the substrates, and the liquid crystal A liquid crystal display element in which is aligned can also be obtained.

  Therefore, the thermosetting film-forming composition having photo-alignment property of the present invention can be suitably used for various optical anisotropic films and liquid crystal display elements.

  Hereinafter, the present embodiment will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

[Compositional components used in Examples and their abbreviations]
Each composition component used in the following examples and comparative examples is as follows.

<Polymer raw material>
CIN1: (E) -2- (methacryloyloxy) ethyl 3- (4- (4-propylcyclohexyl) phenyl) acrylate CIN2: 6-hydroxyhexyloxycinnamic acid methyl ester and 2-isocyanatoethyl methacrylate CIN3: 4- (6-methacryloxyhexyl-1-oxy) cinnamic acid methyl ester CIN4: 4- (6-methacryloxyhexyl-1-oxy) cinnamic acid MAA: methacrylic acid MAM : Methacrylamide GMA: Glycidyl methacrylate MMA: Methyl methacrylate AAM: Acrylamide P-95: Soluble nylon resin (manufactured by Toray)
AIBN: α, α′-azobisisobutyronitrile BETAC: benzyltriethylammonium chloride BHT: dibutylhydroxytoluene <solvent>
Each of the phase difference material forming resin compositions of Examples and Comparative Examples contained a solvent, and propylene glycol monomethyl ether (PM), cyclohexanone (CH), and triethylamine (TEA) were used as the solvent.

<Measurement of molecular weight of polymer>
The molecular weight of the acrylic copolymer in the polymerization example is as follows using a room temperature gel permeation chromatography (GPC) apparatus (GPC-101) manufactured by Shodex Co., Ltd. and columns (KD-803, KD-805) manufactured by Shodex Co. And measured.
The following number average molecular weight (hereinafter referred to as Mn) and weight average molecular weight (hereinafter referred to as Mw) were expressed in terms of polystyrene.
Column temperature: 50 ° C
Eluent: N, N-dimethylformamide (as additives, lithium bromide-hydrate (LiBr · H ₂ O) is 30 mmol / L, phosphoric acid / anhydrous crystal (o-phosphoric acid) is 30 mmol / L, tetrahydrofuran (THF) is 10 mL / L)
Flow rate: 1.0 mL / min Standard sample for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight: about 900,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation and polyethylene glycol (manufactured by Polymer Laboratories) Molecular weight about 12,000, 4,000, 1,000).

<Polymerization example 1>
CIN1 6.0 g, MAA 4.0 g, and AIBN 0.3 g as a polymerization catalyst were dissolved in 41.2 g of PM and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration 20% by mass) ( P1) was obtained. Mn of the obtained acrylic copolymer was 70,00 and Mw was 12,600.

<Polymerization example 2>
CIN2 7.0 g, MAA 3.0 g, and AIBN 0.3 g as a polymerization catalyst were dissolved in PM 33.0 g and CH 8.2 g, and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration). 20% by mass) (P2) was obtained. Mn of the obtained acrylic copolymer was 9,500 and Mw was 20,400.

<Polymerization Example 3>
CIN2 7.0 g, MAM 3.0 g, and AIBN 0.3 g as a polymerization catalyst were dissolved in PM 33.0 g and CH 8.2 g and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration). 20% by mass) (P3) was obtained. Mn of the obtained acrylic copolymer was 11,200 and Mw was 22,800.

<Polymerization example 4>
CIN3 7.0 g, MAM 3.0 g, and AIBN 0.3 g as a polymerization catalyst were dissolved in PM 33.0 g and CH 8.2 g, and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration). 20% by mass) (P4) was obtained. Mn of the obtained acrylic copolymer was 5,100 and Mw was 7,000.

<Polymerization example 5>
CIN3 6.0 g, MAA 4.0 g, and AIBN 0.3 g as a polymerization catalyst were dissolved in PM 33.0 g and CH 8.2 g, and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration). 20% by mass) (P5) was obtained. Mn of the obtained acrylic copolymer was 10,300 and Mw was 34,300.

<Polymerization Example 6>
CIN2 8.0 g, MAA 8.0 g, and AIBN 0.5 g as a polymerization catalyst were dissolved in PM 52.7 g and CH 13.2 g, and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration). 20% by mass) was obtained. Mn of the obtained acrylic copolymer was 9,500 and Mw was 21,000. An acrylic copolymer having a polymerizable double bond group is prepared by dissolving 0.5 g of GMA, 0.01 g of BTEAC, and 0.01 g of BHT in 15.4 g of this acrylic copolymer solution and reacting at 90 ° C. for 20 hours. A polymer solution (solid concentration 22.5% by mass) (P6) was obtained.

<Polymerization Example 7>
CIN2 10.0 g, AIBN 0.3 g as a polymerization catalyst was dissolved in PM 33.0 g and CH 8.2 g, and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration 20 mass%) ( P7) was obtained. Mn of the obtained acrylic copolymer was 9,700 and Mw was 18,500.

<Polymerization Example 8>
CIN4 7.0 g, MMA 3.0 g, and AIBN 0.3 g as a polymerization catalyst were dissolved in 41.2 g of PM and reacted at 80 ° C. for 20 hours to obtain an acrylic copolymer solution (solid content concentration 20% by mass) ( P8) was obtained. Mn of the obtained acrylic copolymer was 12,000 and Mw was 30,000.

<Polymerization example 9>
7.0 g of MMA, 3.0 g of AAM, 0.5 g of AIBN as a polymerization catalyst were dissolved in 41.2 g of PM, and reacted at 80 ° C. for 20 hours, whereby an acrylic copolymer solution (solid content concentration 20 mass%) ( P3) was obtained.

<Examples 1-9, Comparative Examples 1-7>
The components shown in Table 1 were mixed with the components (A) to (B) and the solvent, and Examples 1 to 1 were prepared by adjusting the amount of the solvent added so that the solid content concentration of the final composition was 5% by mass. 9. The cured film forming composition of Comparative Examples 1-7 was prepared. The orientation sensitivity of the obtained composition was evaluated. In addition, the composition ratio in Table 1 represents the ratio in solid content.

[Evaluation of orientation sensitivity]
After each cured film forming composition of Examples and Comparative Examples was applied on a TAC film or an acrylic film using a bar coater, the cured film was dried by heating in a thermal circulation oven at a temperature of 100 ° C. for 2 minutes. Formed. Each cured film was vertically irradiated with 313 nm linearly polarized light to form an alignment material. A horizontal alignment polymerizable liquid crystal solution is applied onto an alignment material on a substrate using a bar coater, and then heated and dried on a hot plate at 75 ° C. for 60 seconds to form a coating film having a thickness of 1.0 μm. did. The coating film on the substrate was irradiated with 300 mJ / cm ² of ultraviolet light to prepare a retardation material. The retardation material on the prepared substrate is sandwiched between a pair of polarizing plates, the state of retardation property development in the retardation material is observed, and the exposure amount of polarized UV necessary for the alignment material to exhibit liquid crystal alignment is determined. It was.

[Evaluation results]
Table 2 shows the results of the above evaluation.

The alignment materials obtained using the cured film-forming compositions of Examples 1 to 9 have a low value of ⁵ to 10 mJ / cm ² for the exposure amount of polarized UV necessary to exhibit liquid crystal alignment. Good alignment sensitivity was exhibited.

On the other hand, the cured films obtained using the cured film forming compositions of Comparative Examples 1 to 7 require a high exposure amount of 35 mJ / cm ^{2 in} order to exhibit liquid crystal alignment, or an exposure of 50 mJ / cm ² or more. Even when an amount of polarized UV light was irradiated, the liquid crystal alignment was poor.

  As described above, the cured film obtained from the thermosetting film-forming composition having the photo-alignment property of the present invention obtained results showing good liquid crystal alignment properties.

  The polyester composition for forming a thermosetting film according to the present invention is very useful as an optically anisotropic film or a liquid crystal alignment layer of a liquid crystal display element, and further various types such as a thin film transistor (TFT) type liquid crystal display element and an organic EL element. Materials for forming a cured film such as a protective film, a planarizing film, and an insulating film in a display, especially as a material for forming an interlayer insulating film for a TFT liquid crystal element, a protective film for a color filter, an insulating film for an organic EL element, etc. Is preferred.

Claims (12)

As the component (A), a repeating unit having a photoalignment group, a polymer having one or more groups selected from a CONH ₂ group and a COOH group only in a repeating unit other than the repeating unit, and a solvent, A hydrogen-bonded cured film-forming composition having photoalignment, characterized by satisfying the following (I):
(I): When one or more groups selected from the CONH ₂ group and the COOH group of the component (A) are only COOH groups, a urethane bond is further present in the side chain of the component (A), or (B And a polymer having at least one selected from a CONH ₂ group and a urethane bond in the repeating unit as an essential component. The composition for forming a hydrogen-bonded cured film according to claim 1, which does not contain a crosslinking agent that reacts with any one of a CONH ₂ group, a COOH group, and a urethane bond. Urethane bond hydrogen bonding cured film-shaped formed composition according to claim 1 or 2, characterized in that present on the side chain with a photoreactive group. The hydrogen bond cured film forming composition in any one of Claims 1 thru | or 3 whose (A) component is an acrylic polymer. The hydrogen bond cured film forming composition in any one of Claims 1 thru | or 3 whose photo-alignment group of (A) component is a functional group of the structure which carries out photodimerization or photoisomerization. The hydrogen bond cured film forming composition in any one of Claims 1 thru | or 4 whose photo-alignment group of (A) component is a cinnamoyl group. The hydrogen bond cured film forming composition in any one of Claims 1 thru | or 4 whose photo-alignment group of (A) component is group of azobenzene structure. The hydrogen bond cured film forming composition in any one of Claims 1 thru | or 7 containing the solvent which can form a hydrogen bond with (A) component and / or (B) component. The composition for forming a hydrogen bond cured film according to any one of claims 2 to 8, wherein the ratio of the component (A) is 5 to 100% by mass based on the total amount of the component (A) and the component (B). The hydrogen in any one of Claims 1 thru | or 9 whose presence rate of the unit structure which has a photo-alignment group in the polymer of (A) component is 50 to 90 mass% based on the total mass of this polymer. Bonded cured film forming composition. An alignment material obtained by using the hydrogen bond cured film forming composition according to claim 1. A retardation material comprising a cured film obtained from the hydrogen-bonded cured film-forming composition according to claim 1.