WO2025170009A1 - Cured film-forming composition, alignment material, and retardation material - Google Patents

Abstract

[Problem] To provide a cured film-forming composition that involves the use of a film such as an acrylic film as a base material, has excellent solvent resistance, is capable of aligning a polymerizable liquid crystal with high sensitivity, and is for forming a cured film used to form an alignment material with little cissing by low-temperature firing at less than 100°C. [Solution] A cured film-forming composition containing (A) a low molecular compound having a photo-alignable group and a thermally crosslinkable group, (B) a crosslinking agent having an N-hydroxymethyl group or an N-alkoxymethyl group, (C) a polymer in which 60 mol% or more of the total repeating units include a hydroxyl group, (D) a polymer that has a repeating unit having a hydroxyl group and in which a repeating unit represented by formula (X) accounts for 45 mol% or more of the total repeating units, (E) inorganic fine particles surface-modified with a group having no (meth)acrylic groups, (F) a low molecular compound having both a (meth)acrylic group and a hydroxy group, and (G) a crosslinking catalyst. (In the formula, R¹ represents a hydrogen atom or a methyl group, and R² represents a linear or branched alkyl group having 1-5 carbon atoms.)

Description

Cured film-forming composition, alignment material, and retardation material

The present invention relates to a cured film-forming composition that forms a cured film that aligns liquid crystal molecules, a cured film, an optical film, an alignment material, and a retardation material. In particular, the present invention relates to a patterned retardation material used in 3D displays that use circularly polarized glasses, and a retardation material used in circular polarizers that are used as anti-reflection films in organic EL displays, as well as a cured film-forming composition, a cured film, an optical film, an alignment material, and a retardation material that are useful for producing the retardation material.

In circularly polarized glasses-based 3D displays, the alignment material is typically a retardation material placed on a display element that forms an image, such as a liquid crystal panel. The retardation material used for this purpose has a patterned configuration in which two types of retardation regions with different retardation characteristics are regularly arranged in multiples. Note that, hereafter in this specification, such a patterned retardation material that arranges multiple retardation regions with different retardation characteristics will be referred to as a patterned retardation material.

Patterned retardation materials can be produced by optically patterning a retardation material made of polymerizable liquid crystals, as disclosed in Patent Document 1, for example. Optical patterning of retardation materials made of polymerizable liquid crystals utilizes photo-alignment technology known for forming alignment materials for liquid crystal panels. That is, a coating film made of a photo-alignable material is provided on a substrate, and two types of polarized light with different polarization directions are irradiated onto it. A photo-alignment film is then obtained as an alignment material in which two types of liquid crystal alignment regions with different liquid crystal alignment control directions are formed. A solution-like retardation material containing polymerizable liquid crystals is applied onto this photo-alignment film to achieve alignment of the polymerizable liquid crystals. The oriented polymerizable liquid crystal is then cured to form a patterned retardation material.

Anti-reflection coatings on organic EL displays are composed of a linear polarizer and a quarter-wave retardation plate. External light directed toward the surface of the image display panel is converted into linearly polarized light by the linear polarizer, and then converted into circularly polarized light by the subsequent quarter-wave retardation plate. This circularly polarized external light is reflected by the surface of the image display panel, but the direction of rotation of the polarization plane is reversed during this reflection. As a result, this reflected light is converted by the quarter-wave retardation plate into linearly polarized light in a direction that is blocked by the linear polarizer, in the opposite direction to when it arrived, and is then blocked by the subsequent linear polarizer, resulting in significant suppression of external emission.

Regarding quarter-wave retardation plates, Patent Document 2 proposes a method of constructing this optical film with reverse dispersion characteristics by combining a half-wave plate and a quarter-wave plate to form a quarter-wave retardation plate. With this method, an optical film with reverse dispersion characteristics can be constructed using a liquid crystal material with positive dispersion characteristics over the wide wavelength range used to display color images.

In recent years, liquid crystal materials with reverse dispersion characteristics have been proposed as materials suitable for use in this retardation layer (Patent Documents 3 and 4). With such liquid crystal materials with reverse dispersion characteristics, instead of combining a half-wave plate and a quarter-wave plate to form a quarter-wave retardation plate using two retardation layers, it is possible to ensure reverse dispersion characteristics by forming the retardation layer from a single layer, thereby enabling the realization of an optical film with a simple configuration that can ensure the desired retardation over a wide wavelength band.

Alignment layers are used to align liquid crystals. Known methods for forming alignment layers include rubbing and photo-alignment. Photo-alignment is useful because it does not generate static electricity or dust, which are problems with rubbing, and allows for quantitative control of the alignment process.

Acrylic resins and polyimide resins with photodimerization moieties such as cinnamoyl groups and chalcone groups in the side chains are known as photoalignment materials that can be used to form alignment materials using the photoalignment method. These resins have been reported to exhibit the ability to control the alignment of liquid crystals (hereinafter referred to as liquid crystal alignment) when irradiated with polarized UV light (see Patent Documents 5 to 7).

In addition to being able to align liquid crystals, the alignment layer also needs to be solvent-resistant. For example, the alignment layer may be exposed to heat or solvents during the manufacturing process of the retardation material. If an alignment layer lacks solvent resistance and is exposed to solvent, its liquid crystal alignment ability may be significantly reduced.

For example, Patent Document 8 proposes a liquid crystal aligning agent containing a polymer component having a structure capable of undergoing a photo-induced crosslinking reaction and a structure that crosslinks when heated, in order to obtain stable liquid crystal alignment ability, and a liquid crystal aligning agent containing a polymer component having a structure capable of undergoing a photo-induced crosslinking reaction and a compound having a structure that crosslinks when heated.

In addition, the alignment layer must have good adhesion to the liquid crystal layer. If the adhesion between the alignment layer and the liquid crystal layer formed on top of it is insufficient, the liquid crystal layer may peel off, for example, during the winding process when manufacturing the retardation film.

Furthermore, from the standpoint of workability, it is desirable to be able to create an orientation layer by firing at a low temperature of less than 100°C.

Japanese Patent Application Laid-Open No. 2005-49865 Japanese Patent Application Publication No. 10-68816 U.S. Patent No. 8,119,026 JP 2009-179563 A Patent No. 3611342 JP 2009-058584 A Special Publication No. 2001-517719 Patent No. 4207430

When a retardation material is manufactured using photo-alignment technology, in recent years, in response to demands for reduced manufacturing costs, there has been a demand for the production of optical materials using a so-called roll-to-roll method on inexpensive resin films such as acrylic films, TAC (triacetyl cellulose) films, and COP (cycloolefin polymer) films, and there is a particular demand for the use of acrylic films as resin films (substrates) due to their excellent optical properties and reliability, as well as the advantage of being able to reduce manufacturing costs.
However, in the case of a photo-alignment film formed from the above-mentioned conventional materials, it has been difficult to align a polymerizable liquid crystal because the cured film formed by low-temperature baking at less than 100° C. has low solvent resistance. In particular, when a film such as an acrylic film is used as the substrate, the low solvent resistance of the alignment film causes the generation of areas that repel the liquid crystal, so-called repelling, which causes alignment defects.

Therefore, there is a need for a cured film (alignment material) that has excellent solvent resistance, can align polymerizable liquid crystals with high sensitivity, has excellent adhesion to the liquid crystal layer and acrylic film, and causes little liquid crystal repelling. There is also a need for a cured film-forming composition that is suitable for forming a cured film (alignment material) with such properties.

The present invention was made based on the above findings and research results. Specifically, the object of the present invention is to provide a cured film-forming composition that uses a film such as an acrylic film as a substrate, has excellent solvent resistance, is capable of aligning polymerizable liquid crystals with high sensitivity, and can form a cured film used to form an alignment material with little repelling by baking at a low temperature of less than 100°C.

Another object of the present invention is to provide an optical film having the above-mentioned cured film, and an alignment material and a retardation material formed using the cured film or optical film.

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

As a result of extensive research to solve the above problems, the inventors discovered that a cured film obtained from a cured film-forming composition having a specific composition has excellent solvent resistance, is capable of aligning polymerizable liquid crystals with high sensitivity, and can be used as an alignment material that has excellent adhesion to liquid crystal layers and acrylic films and causes little repelling of liquid crystals, thereby completing the present invention.

That is, the first aspect of the present invention is
(A) a low molecular weight compound having a photoalignable group and a thermally crosslinkable group;
(B) a crosslinking agent having an N-hydroxymethyl group or an N-alkoxymethyl group;
(C) a polymer having 60 mol % or more of all repeating units containing a hydroxy group;
(D) A polymer having 45 mol % or more of repeating units represented by the following formula (X) based on all repeating units, and also having a repeating unit having a hydroxy group:
(E) inorganic fine particles whose surface has been modified with a group having no (meth)acrylic group;
The present invention relates to a cured film-forming composition containing (F) a low molecular weight compound having both a (meth)acrylic group and a hydroxy group, and (G) a crosslinking catalyst.
(In the above formula, ^R1 represents a hydrogen atom or a methyl group, and ^R2 represents a linear or branched alkyl group having 1 to 5 carbon atoms.)

In the first aspect of the present invention, the photoalignable group of the component (A) is preferably a functional group having a structure that undergoes photodimerization or photoisomerization.
In the first aspect of the present invention, the photoalignable group of the component (A) is preferably a cinnamoyl group or a group having an azobenzene structure.
In the first aspect of the present invention, the crosslinking agent (B) is preferably a polymer obtained by polymerizing a monomer selected from N-hydroxymethyl(meth)acrylamide and N-alkoxymethyl(meth)acrylamide compounds.

The second aspect of the present invention relates to a cured film obtained from the cured film-forming composition of the first aspect of the present invention.

A third aspect of the present invention relates to an optical film having a cured film according to the second aspect of the present invention.

A fourth aspect of the present invention relates to an alignment material formed using the cured film of the second aspect of the present invention.

The fifth aspect of the present invention relates to a retardation material formed using the cured film of the second aspect of the present invention.

Throughout this specification, (meth)acrylic refers to both acrylic and methacrylic.

According to the present invention, it is possible to provide a cured film-forming composition which can form, by baking at a low temperature of less than 100°C, a cured film that has excellent solvent resistance, can align polymerizable liquid crystals with high sensitivity, causes little liquid crystal repelling, and provides an alignment material that has excellent adhesion to a liquid crystal layer.
Furthermore, according to the present invention, it is possible to provide an optical film having the above-mentioned cured film, and an alignment material and a retardation material formed using the cured film or the optical film.

The cured film-forming composition of the present invention will be described in detail below, citing specific examples of its components, etc. Then, the cured film and alignment material of the present invention that use the cured film-forming composition of the present invention, as well as retardation materials and liquid crystal display elements, etc., that are formed using the alignment material will be described.

<Cured film forming composition>
The cured film-forming composition of the present invention contains (A) a low molecular weight compound having a photoalignable group and a thermally crosslinkable group, (B) a crosslinking agent having an N-hydroxymethyl group or an N-alkoxymethyl group, (C) a polymer having 60 mol % or more of all repeating units containing repeating units having a hydroxy group, (D) a polymer having 45 mol % or more of all repeating units containing repeating units represented by the above formula (X) and repeating units having a hydroxy group, (E) inorganic fine particles surface-modified with a group not containing a (meth)acrylic group, (F) a low molecular weight compound having both a (meth)acrylic group and a hydroxy group, and (G) a crosslinking catalyst. Furthermore, other additives may be added as long as they do not impair the effects of the present invention. Furthermore, the cured film-forming composition of the present invention contains a solvent and can be in the form of a so-called varnish.
Each component will be described in detail below.

[Component (A)]
The component (A) in the cured film-forming composition of the present invention is a low molecular weight compound having a photoalignable group and a thermally crosslinkable group. That is, the component (A) is a component that imparts photoalignment properties to a cured film obtained from the cured film-forming composition of the present invention, and in this specification, the component (A) is also referred to as a photoalignment component.

<Low molecular weight compound having a photoalignment group and a thermal crosslinking group>
The low molecular weight compound of the component (A) is a compound having a lower molecular weight than the polymer of the component (C) described below, which serves as the base for film formation in the cured film-forming composition of the present invention, and serves as a photoalignment component in the cured film-forming composition.

In the cured film-forming composition of the present invention, the low-molecular-weight compound of component (A) is a compound having a photoalignable group and further having a thermally crosslinkable group which is at least one group selected from the group consisting of a hydroxy group, a carboxy group, an amide group, an amino group, and an alkoxysilyl group. The photoalignable group may also contain a carboxy group or an amide group.

In the present invention, the term "photoalignable group" generally refers to a functional group that exhibits the property of alignment upon irradiation with light, and typically refers to a functional group at a structural site that undergoes photodimerization or photoisomerization. Other photoalignable groups include, for example, functional groups that undergo a photo-induced Fries rearrangement reaction (example compounds: benzoic acid ester compounds, etc.) and groups that undergo a photodecomposition reaction (example compounds: cyclobutane rings, etc.).

The photodimerizable structural moiety that the low molecular weight compound of component (A) can have as a photoalignment group is a moiety that forms a dimer upon irradiation with light, and specific examples include cinnamoyl groups, chalcone groups, coumarin groups, and anthracene groups. Of these, cinnamoyl groups are preferred due to their high transparency in the visible light region and high photodimerization reactivity.

Furthermore, the photoisomerizable structural moiety that the low molecular weight compound of component (A) can have as a photoalignment group refers to a structural moiety that changes between cis and trans isomers upon irradiation with light, and specific examples include moieties consisting of an azobenzene structure, a stilbene structure, etc. Of these, the azobenzene structure is preferred due to its high reactivity.

A low molecular weight compound having a photoalignable group and a thermally crosslinkable group (at least one group selected from the group consisting of a hydroxy group, a carboxy group, an amide group, an amino group, and an alkoxysilyl group) is, for example, a compound represented by the following formula:

In the formula, A ¹ and A ² each independently represent a hydrogen atom or a methyl group.

^X11 is a structure in which 1 to 3 substituents selected from an alkylene group having 1 to 18 carbon atoms, a phenylene group, a biphenylene group, or a combination thereof are bonded via one or more bonds selected from a single bond, an ether bond, an ester bond, an amide bond, a urea bond, a urethane bond, an amino bond, a carbonyl bond, or a combination thereof, and a structure in which a plurality of the substituents are linked via the bond may be formed.

^X12 represents a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 18 carbon atoms, a phenyl group, a biphenyl group, or a cyclohexyl group, wherein two or more groups may be bonded to the alkyl group having 1 to 18 carbon atoms, the phenyl group, the biphenyl group, and the cyclohexyl group via a covalent bond, an ether bond, an ester bond, an amide bond, or a urea bond.

X ¹³ represents a hydroxy group, a mercapto group, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, a phenoxy group, a biphenyloxy group, or a phenyl group.

^X14 represents a single bond, an alkylene group having 1 to 20 carbon atoms, a divalent aromatic ring group, or a divalent aliphatic ring group, wherein the alkylene group having 1 to 20 carbon atoms may be branched or linear.

X ¹⁵ represents a hydroxy group, a carboxy group, an amide group, an amino group or an alkoxysilyl group, provided that when X ¹⁴ is a single bond, X ¹⁵ is a hydroxy group or an amino group.

X represents a single bond, an oxygen atom, or a sulfur atom, provided that when X ¹⁴ is a single bond, X is also a single bond.

In addition, when these substituents contain a benzene ring, the benzene ring may be substituted with one or more identical or different substituents selected from an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom, a trifluoromethyl group, and a cyano group.

In the above formula, R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ 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.

Specific examples of the low molecular weight compound having a photoalignable group and a hydroxy group, which is the component (A), include compounds represented by the above formulas [A11] to [A15], as well as compounds other than those formulas, such as 4-(8-hydroxyoctyloxy)cinnamic acid methyl ester, 4-(6-hydroxyhexyloxy)cinnamic acid methyl ester, 4-(4-hydroxybutyloxy)cinnamic acid methyl ester, 4-(3-hydroxypropyloxy)cinnamic acid methyl ester, and 4-(2-hydroxyethyloxy)cinnamic acid methyl ester. ethyl ester, 4-hydroxymethyloxycinnamic acid methyl ester, 4-hydroxycinnamic acid methyl ester, 4-(8-hydroxyoctyloxy)cinnamic acid ethyl ester, 4-(6-hydroxyhexyloxy)cinnamic acid ethyl ester, 4-(4-hydroxybutyloxy)cinnamic acid ethyl ester, 4-(3-hydroxypropyloxy)cinnamic acid ethyl ester, 4-(2-hydroxyethyloxy)cinnamic acid ethyl ester, 4-hydroxymethyloxycinnamic acid ethyl ester, 4-hydroxy hydroxycinnamic acid ethyl ester, 4-(8-hydroxyoctyloxy)cinnamic acid phenyl ester, 4-(6-hydroxyhexyloxy)cinnamic acid phenyl ester, 4-(4-hydroxybutyloxy)cinnamic acid phenyl ester, 4-(3-hydroxypropyloxy)cinnamic acid phenyl ester, 4-(2-hydroxyethyloxy)cinnamic acid phenyl ester, 4-hydroxymethyloxycinnamic acid phenyl ester, 4-hydroxycinnamic acid phenyl ester, 4-(8-hydroxyoctyloxy)cinnamic acid phenyl ester 4-(6-hydroxyhexyloxy)cinnamic acid biphenyl ester, 4-(4-hydroxybutyloxy)cinnamic acid biphenyl ester, 4-(3-hydroxypropyloxy)cinnamic acid biphenyl ester, 4-(2-hydroxyethyloxy)cinnamic acid biphenyl ester, 4-hydroxymethyloxycinnamic acid biphenyl ester, 4-hydroxycinnamic acid biphenyl ester, cinnamic acid 8-hydroxyoctyl ester, cinnamic acid 6-hydroxyhexyl esters, cinnamic acid 4-hydroxybutyl ester, cinnamic acid 3-hydroxypropyl ester, cinnamic acid 2-hydroxyethyl ester, cinnamic acid hydroxymethyl ester, 4-(8-hydroxyoctyloxy)azobenzene, 4-(6-hydroxyhexyloxy)azobenzene, 4-(4-hydroxybutyloxy)azobenzene, 4-(3-hydroxypropyloxy)azobenzene, 4-(2-hydroxyethyloxy)azobenzene, 4-hydroxymethyloxyazobenzene, 4-hydroxyazobenzene hydroxyazobenzene, 4-(8-hydroxyoctyloxy)chalcone, 4-(6-hydroxyhexyloxy)chalcone, 4-(4-hydroxybutyloxy)chalcone, 4-(3-hydroxypropyloxy)chalcone, 4-(2-hydroxyethyloxy)chalcone, 4-hydroxymethyloxychalcone, 4-hydroxychalcone, 4'-(8-hydroxyoctyloxy)chalcone, 4'-(6-hydroxyhexyloxy)chalcone, 4'-(4-hydroxybutyloxy)chalcone, 4'- (3-hydroxypropyloxy)chalcone, 4'-(2-hydroxyethyloxy)chalcone, 4'-hydroxymethyloxychalcone, 4'-hydroxychalcone, 7-(8-hydroxyoctyloxy)coumarin, 7-(6-hydroxyhexyloxy)coumarin, 7-(4-hydroxybutyloxy)coumarin, 7-(3-hydroxypropyloxy)coumarin, 7-(2-hydroxyethyloxy)coumarin, 7-hydroxymethyloxycoumarin, 7-hydroxycoumarin, 6-hydroxyoctyloxy Octyloxycoumarin, 6-hydroxyhexyloxycoumarin, 6-(4-hydroxybutyloxy)coumarin, 6-(3-hydroxypropyloxy)coumarin, 6-(2-hydroxyethyloxy)coumarin, 6-hydroxymethyloxycoumarin, 6-hydroxycoumarin, 4-[4-(8-hydroxyoctyloxy)benzoyl]cinnamic acid methyl ester, 4-[4-(6-hydroxyhexyloxy)benzoyl]cinnamic acid methyl ester, 4-[4-(4-hydroxybutyloxy)benzo 4-[4-(3-hydroxypropyloxy)benzoyl]cinnamic acid methyl ester, 4-[4-(2-hydroxyethyloxy)benzoyl]cinnamic acid methyl ester, 4-[4-hydroxymethyloxybenzoyl]cinnamic acid methyl ester, 4-[4-hydroxybenzoyl]cinnamic acid methyl ester, 4-[4-(8-hydroxyoctyloxy)benzoyl]cinnamic acid ethyl ester, 4-[4-(6-hydroxyhexyloxy)benzoyl]cinnamic acid ethyl ester esters, 4-[4-(4-hydroxybutyloxy)benzoyl]cinnamic acid ethyl ester, 4-[4-(3-hydroxypropyloxy)benzoyl]cinnamic acid ethyl ester, 4-[4-(2-hydroxyethyloxy)benzoyl]cinnamic acid ethyl ester, 4-[4-hydroxymethyloxybenzoyl]cinnamic acid ethyl ester, 4-[4-hydroxybenzoyl]cinnamic acid ethyl ester, 4-[4-(8-hydroxyoctyloxy)benzoyl]cinnamic acid tert-butyl ester, 4-[4-(6-hydroxyhexyloxy)benzoyl]cinnamic acid tert-butyl ester, 4-[4-(4-hydroxybutyloxy)benzoyl]cinnamic acid tert-butyl ester, 4-[4-(3-hydroxypropyloxy)benzoyl]cinnamic acid tert-butyl ester, 4-[4-(2-hydroxyethyloxy)benzoyl]cinnamic acid tert-butyl ester, 4-[4-hydroxymethyloxybenzoyl]cinnamic acid tert-butyl ester, 4-[4-hydroxy 4-[4-(4-hydroxypropyloxy)benzoyl]cinnamic acid phenyl ester, 4-[4-(2-hydroxyethyloxy)benzoyl]cinnamic acid phenyl ester, 4-[4-(4-hydroxybutyloxy)benzoyl]cinnamic acid phenyl ester, 4-[4-(3-hydroxypropyloxy)benzoyl]cinnamic acid phenyl ester, 4-[4-(2-hydroxyethyloxy)benzoyl]cinnamic acid phenyl ester, 4-[4- 4-[4-hydroxymethyloxybenzoyl]cinnamic acid phenyl ester, 4-[4-hydroxybenzoyl]cinnamic acid phenyl ester, 4-[4-(8-hydroxyoctyloxy)benzoyl]cinnamic acid biphenyl ester, 4-[4-(6-hydroxyhexyloxy)benzoyl]cinnamic acid biphenyl ester, 4-[4-(4-hydroxybutyloxy)benzoyl]cinnamic acid biphenyl ester, 4-[4-(3-hydroxypropyloxy)benzoyl]cinnamic acid biphenyl ester, 4-[4- (2-hydroxyethyloxy)benzoyl]cinnamic acid biphenyl ester, 4-[4-hydroxymethyloxybenzoyl]cinnamic acid biphenyl ester, 4-[4-hydroxybenzoyl]cinnamic acid biphenyl ester, 4-benzoylcinnamic acid 8-hydroxyoctyl ester, 4-benzoylcinnamic acid 6-hydroxyhexyl ester, 4-benzoylcinnamic acid 4-hydroxybutyl ester, 4-benzoylcinnamic acid 3-hydroxypropyl ester, 4-benzoylcinnamic acid 2-hydroxyethyl ester Ester, 4-benzoylcinnamic acid hydroxymethyl ester, 4-[4-(8-hydroxyoctyloxy)benzoyl]chalcone, 4-[4-(6-hydroxyhexyloxy)benzoyl]chalcone, 4-[4-(4-hydroxybutyloxy)benzoyl]chalcone, 4-[4-(3-hydroxypropyloxy)benzoyl]chalcone, 4-[4-(2-hydroxyethyloxy)benzoyl]chalcone, 4-(4-hydroxymethyloxybenzoyl)chalcone, 4-(4-hydroxybenzo yl)chalcone, 4'-[4-(8-hydroxyoctyloxy)benzoyl]chalcone, 4'-[4-(6-hydroxyhexyloxy)benzoyl]chalcone, 4'-[4-(4-hydroxybutyloxy)benzoyl]chalcone, 4'-[4-(3-hydroxypropyloxy)benzoyl]chalcone, 4'-[4-(2-hydroxyethyloxy)benzoyl]chalcone, 4'-(4-hydroxymethyloxybenzoyl)chalcone, 4'-(4-hydroxybenzoyl)chalcone, etc.

Specific examples of the low molecular weight compound (A) having a photoalignable group and a carboxy group include cinnamic acid, ferulic acid, 4-methoxycinnamic acid, 4-propoxycinnamic acid, 3,4-dimethoxycinnamic acid, coumarin-3-carboxylic acid, and 4-(N,N-dimethylamino)cinnamic acid.

Specific examples of the low molecular weight compound having a photoalignable group and an amide group, component (A), include cinnamic acid amide, 4-methylcinnamic acid amide, 4-ethylcinnamic acid amide, 4-methoxycinnamic acid amide, and 4-ethoxycinnamic acid amide.

Specific examples of the low molecular weight compound having a photoalignable group and an amino group, which is component (A), include 4-aminocinnamic acid methyl ester, 4-aminocinnamic acid ethyl ester, 3-aminocinnamic acid methyl ester, and 3-aminocinnamic acid ethyl ester.

Specific examples of the low molecular weight compound having a photoalignable group and an alkoxysilyl group, component (A), include 4-(3-trimethoxysilylpropyloxy)cinnamic acid methyl ester, 4-(3-triethoxysilylpropyloxy)cinnamic acid methyl ester, 4-(3-trimethoxysilylpropyloxy)cinnamic acid ethyl ester, 4-(3-triethoxysilylpropyloxy)cinnamic acid ethyl ester, 4-(3-trimethoxysilylhexyloxy)cinnamic acid methyl ester, 4-(3-triethoxysilylhexyloxy)cinnamic acid methyl ester, 4-(3-trimethoxysilylhexyloxy)cinnamic acid ethyl ester, 4-(3-triethoxysilylhexyloxy)cinnamic acid ethyl ester, 4-(3-triethoxysilylhexyloxy)cinnamic acid ethyl ester, and 4-(3-triethoxysilylhexyloxy)cinnamic acid ethyl ester.

The low molecular weight compound of component (A) is preferably a compound in which a polymerizable group is bonded via a spacer to a group in which a photoalignable moiety and a thermally crosslinkable moiety are bonded, as represented by the following formula (1):
(In the formula, R ¹⁰¹ represents a hydroxy group, an amino group, a hydroxyphenoxy group, a carboxyphenoxy group, an aminophenoxy group, an aminocarbonylphenoxy group, a phenylamino group, a hydroxyphenylamino group, a carboxyphenylamino group, an aminophenylamino group, a hydroxyalkylamino group, or a bis(hydroxyalkyl)amino group; X ¹⁰¹ represents a phenylene group which may be substituted with any substituent; and the benzene ring in these definitions may be substituted with a substituent.)

When the benzene ring has a substituent, examples of the substituent include alkyl groups such as methyl, ethyl, propyl, butyl, and isobutyl; haloalkyl groups such as trifluoromethyl; alkoxy groups such as methoxy and ethoxy; halogen atoms such as iodine, bromine, chlorine, and fluorine; cyano; and nitro.

As R ¹⁰¹ in the above formula (1), a hydroxy group and an amino group are preferred, and a hydroxy group is particularly preferred.

The spacer may be a divalent group selected from a linear alkylene group, a branched alkylene group, a cyclic alkylene group, and a phenylene group, or a group formed by bonding multiple such divalent groups. In this case, the bond between the divalent groups constituting the spacer, the bond between the spacer and the group represented by formula (1) above, and the bond between the spacer and the polymerizable group may be a single bond, an ester bond, an amide bond, a urea bond, or an ether bond. When there are multiple divalent groups, the divalent groups may be the same or different, and when there are multiple bonds, the bonds may be the same or different.

Specific examples of such low molecular weight compounds (A) in which a polymerizable group is bonded to a group comprising a photoalignment moiety and a thermal crosslinking moiety include 4-(6-methacryloxyhexyl-1-oxy)cinnamic acid, 4-(6-acryloxyhexyl-1-oxy)cinnamic acid, 4-(3-methacryloxypropyl-1-oxy)cinnamic acid, 4-(4-(3-methacryloxypropyl-1-oxy)acryloxy)benzoic acid, 4-(4-(6-methacryloxyhexyl-1-oxy)benzoyloxy)cinnamic acid, 4-(6-methacryloxyhexyl-1-oxy)cinnamamide, 4-(6-methacryloxyhexyl-1-oxy)-N-(4-cyanophenyl)cinnamamide, and 4-(6-methacryloxyhexyl-1-oxy)-N-bishydroxyethylcinnamamide.

Specific examples of the low-molecular-weight photoalignment component (A) include, but are not limited to, the above.

As described above, in the present invention, a low molecular weight compound can be used as component (A). Component (A) may also be a mixture of one or more low molecular weight compounds.

[(B) Component]
The component (B) contained in the cured film-forming composition of the present embodiment is a crosslinking agent having an N-hydroxymethyl group or an N-alkoxymethyl group, and more specifically, includes an N-hydroxymethyl compound, an N-alkoxymethyl compound, or a polymer obtained by polymerizing a monomer selected from N-hydroxymethyl(meth)acrylamide and N-alkoxymethyl(meth)acrylamide compounds.

N-hydroxymethyl compounds and N-alkoxymethyl compounds include, for example, methylol compounds such as alkoxymethylated glycoluril, alkoxymethylated benzoguanamine, and alkoxymethylated melamine.

Specific examples of alkoxymethylated glycolurils include 1,3,4,6-tetrakis(methoxymethyl)glycoluril, 1,3,4,6-tetrakis(butoxymethyl)glycoluril, 1,3,4,6-tetrakis(hydroxymethyl)glycoluril, 1,3-bis(hydroxymethyl)urea, 1,1,3,3-tetrakis(butoxymethyl)urea, 1,1,3,3-tetrakis(methoxymethyl)urea, 1,3-bis(hydroxymethyl)-4,5-dihydroxy-2-imidazolinone, and 1,3-bis(methoxymethyl)-4,5-dimethoxy-2-imidazolinone. Commercially available products include glycoluril compounds (trade names: Cymel (registered trademark) 1170, Powderlink (registered trademark) 1174) manufactured by Nippon Cytec Industries Co., Ltd. (formerly Mitsui Cytec Co., Ltd.), methylated urea resin (trade name: UFR (registered trademark) 65), butylated urea resin (trade name: UFR (registered trademark) 300, U-VAN10S60, U-VAN10R, U-VAN11HV), and urea/formaldehyde resin (high condensation type, trade name: Beckamin (registered trademark) J-300S, P-955, N) manufactured by DIC Corporation (formerly Dainippon Ink and Chemicals Co., Ltd.).

Specific examples of alkoxymethylated benzoguanamine include tetramethoxymethylbenzoguanamine. Commercially available products include those manufactured by Nippon Cytec Industries Co., Ltd. (formerly Mitsui Cytec Co., Ltd.) (product name: Cymel (registered trademark) 1123) and those manufactured by Sanwa Chemical Co., Ltd. (product names: Nikalac (registered trademark) BX-4000, BX-37, BL-60, and BX-55H).

Specific examples of alkoxymethylated melamine include hexamethoxymethyl melamine. Commercially available products include methoxymethyl-type melamine compounds (trade names: Cymel® 300, 301, 303, and 350) and butoxymethyl-type melamine compounds (trade names: Mycoat® 506 and 508) manufactured by Nihon Cytec Industries Co., Ltd. (formerly Mitsui Cytec Co., Ltd.), and methoxymethyl-type melamine compounds (trade names: Nikalac® MW-30, MW-22, MW-11, MS-001, MX-002, MX-730, MX-750, and MX-035) and butoxymethyl-type melamine compounds (trade names: Nikalac® MX-45, MX-410, and MX-302) manufactured by Sanwa Chemical Co., Ltd.

Furthermore, compounds obtained by condensing melamine compounds, urea compounds, glycoluril compounds, and benzoguanamine compounds in which the hydrogen atoms of the amino groups have been substituted with methylol groups or alkoxymethyl groups may also be used. Examples include the high-molecular-weight compounds produced from melamine compounds and benzoguanamine compounds described in U.S. Patent No. 6,323,310. Commercially available melamine compounds include Cymel (registered trademark) 303, and commercially available benzoguanamine compounds include Cymel (registered trademark) 1123 (both manufactured by Nippon Cytec Industries Co., Ltd. (formerly Mitsui Cytec Co., Ltd.)).

Polymers obtained by polymerizing a monomer selected from N-hydroxymethyl(meth)acrylamide and N-alkoxymethyl(meth)acrylamide compounds include polymers obtained by polymerizing a monomer such as N-alkoxymethyl(meth)acrylamide or N-hydroxymethyl(meth)acrylamide, either alone or copolymerized with a copolymerizable monomer. Examples of such polymers include poly(N-butoxymethylacrylamide), poly(N-ethoxymethylacrylamide), poly(N-methoxymethylacrylamide), poly(N-hydroxymethylacrylamide), copolymers of N-butoxymethylacrylamide and styrene, copolymers of N-butoxymethylacrylamide and methyl methacrylate, copolymers of N-ethoxymethylmethacrylamide and benzyl methacrylate, and copolymers of N-butoxymethylacrylamide, benzyl methacrylate, and 2-hydroxypropyl methacrylate. The weight-average molecular weight of such polymers is 1,000 to 500,000, preferably 2,000 to 200,000, more preferably 3,000 to 150,000, and even more preferably 3,000 to 50,000. The weight-average molecular weight is a value obtained by gel permeation chromatography (GPC) using polystyrene as a standard. The same applies hereinafter in this specification.

These crosslinking agents for component (B) can be used alone or in combination of two or more.

In the cured film-forming composition of this embodiment, the content of the crosslinking agent having an N-hydroxymethyl group or an N-alkoxymethyl group as component (B) is preferably 100 to 2,000 parts by mass, and more preferably 200 to 1,500 parts by mass, based on 100 parts by mass of the compound as component (A).

[(C) Component]
The component (C) contained in the cured film-forming composition of the present invention is a polymer (hereinafter also referred to as specific polymer C) having, as a unit structure, repeating units having a hydroxy group in an amount of 60 mol % or more of all repeating units.

Examples of the polymer that is component (C) include acrylic polymers, urethane-modified acrylic polymers, polyamic acids, polyimides, polyvinyl alcohols, polyesters, polyester polycarboxylic acids, polyether polyols, polyester polyols, polycarbonate polyols, polycaprolactone polyols, polyalkyleneimines, polyallylamine, celluloses (cellulose or derivatives thereof), polymers with a linear or branched chain structure such as phenol novolac resins, and cyclic polymers such as cyclodextrins.

Among these, acrylic polymers include polymers obtained by (co)polymerizing acrylic acid esters, methacrylic acid esters, and these with monomers having unsaturated double bonds, such as styrene. A simple synthesis method is to (co)polymerize a monomer having a hydroxy group and, if desired, other monomers.

Examples of monomers 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-acryloyloxy-6-hydroxynorbornene-2-carboxylic-6-lactone, and 5-methacryloyloxy-6-hydroxynorbornene-2-carboxylic-6-lactone.

Among these, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate are particularly preferred.

Furthermore, in the cured film-forming composition of the present invention, when obtaining specific polymer C, a monomer copolymerizable with the monomer having a hydroxy group (hereinafter also referred to as a monomer having a non-reactive functional group) can be used in combination.

Specific examples of such monomers having a non-reactive functional group include acrylic acid ester compounds, methacrylic acid ester compounds, maleimide compounds, acrylamide compounds, acrylonitrile, maleic anhydride, styrene compounds, and vinyl compounds.
Specific examples of the monomer having the non-reactive functional group are listed below, but the present invention is not limited to these.

Examples of the acrylic acid ester compounds mentioned above include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, benzyl acrylate, naphthyl acrylate, anthryl acrylate, anthrylmethyl acrylate, phenyl acrylate, glycidyl acrylate, 2,2,2-trifluoroethyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, and 8-ethyl-8-tricyclodecyl acrylate.

Examples of the methacrylic acid ester compounds mentioned above include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthryl methacrylate, anthrylmethyl methacrylate, phenyl methacrylate, glycidyl methacrylate, 2,2,2-trifluoroethyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl-2-adamantyl methacrylate, γ-butyrolactone methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, and 8-ethyl-8-tricyclodecyl methacrylate.

Examples of the maleimide compounds mentioned above include maleimide, N-methylmaleimide, N-phenylmaleimide, and N-cyclohexylmaleimide.

Examples of the styrene compounds mentioned above include styrene, methylstyrene, chlorostyrene, bromostyrene, etc.

Examples of the vinyl compounds mentioned above 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.

The method for obtaining the specific polymer C used in the cured film-forming composition of the present invention is not particularly limited, but examples include a method of carrying out a polymerization reaction at a temperature of 50°C to 110°C in a solvent containing a monomer having a hydroxy group, optionally a monomer having a non-reactive functional group, a polymerization initiator, etc. The solvent used in this case is not particularly limited, as long as it dissolves the monomer having a hydroxy group, optionally a monomer having a non-reactive functional group, and a polymerization initiator, etc. Specific examples include the solvents described below under [Solvent].

The specific polymer C obtained in this manner is usually in the form of a solution dissolved in a solvent, and can be used as is as the polymer solution of component (C) in the present invention.

Furthermore, the solution of specific polymer C obtained as described above can be reprecipitated by adding it to diethyl ether, water, or the like while stirring. The resulting precipitate can be filtered and washed, and then dried at room temperature or by heating under normal or reduced pressure to obtain a powder of specific polymer C. This procedure makes it possible to remove the polymerization initiator and unreacted monomers that coexist with specific polymer C, resulting in a purified powder of specific polymer C. If sufficient purification cannot be achieved in one procedure, the obtained powder can be redissolved in a solvent and the above procedure can be repeated.

In the cured film-forming composition of the present invention, the powder of the specific polymer C may be used as is as the polymer of component (C), or the powder may be redissolved in, for example, a solvent described below and used in the form of a solution.

The acrylic polymer, an example of component (C), preferably has a weight-average molecular weight of 3,000 to 200,000, more preferably 4,000 to 150,000, and even more preferably 5,000 to 100,000. If the weight-average molecular weight is too high, exceeding 200,000, solubility in solvents may decrease, resulting in poor handling, while if the weight-average molecular weight is too low, below 3,000, the polymer may not cure sufficiently during heat curing, resulting in poor solvent resistance and heat resistance.

Furthermore, in the composition of the present invention, component (C) may be a mixture of multiple types of polymers exemplified as component (C).

The content of component (C) in the cured film-forming composition of the present invention is 50 to 1,500 parts by mass, preferably 100 to 1,000 parts by mass, and more preferably 200 to 500 parts by mass, based on 100 parts by mass of component (A).

[(D) Component]
The component (D) contained in the cured film-forming composition of the present invention is a polymer (hereinafter also referred to as specific copolymer D) having repeating units represented by the following formula (X) in an amount of 45 mol % or more of all repeating units and having a repeating unit having a hydroxy group:
(In the above formula, ^R1 represents a hydrogen atom or a methyl group, and ^R2 represents a linear or branched alkyl group having 1 to 5 carbon atoms.)
Hereinafter, a monomer that provides a repeating unit represented by the above formula (X) will be referred to as a specific monomer X.

Examples of specific monomer X, the alkyl acrylate or alkyl methacrylate monomer, include alkyl acrylate compounds such as methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, and tert-butyl acrylate, and alkyl methacrylate compounds such as methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, and tert-butyl methacrylate.

Among these specific monomers X, methyl methacrylate is particularly preferred in terms of availability and affinity with the acrylic film used as the substrate.
That is, it is preferable that the component (D) is a polymer obtained using methyl methacrylate as a monomer, in other words, a polymer having a unit structure in which R ¹ and R ² in formula (X) both represent a methyl group.

Specific copolymer D, component (D), can be a polymer obtained by polymerizing specific monomer X, such as alkyl acrylate or alkyl methacrylate, as well as a monomer having an unsaturated double bond, such as styrene.

Furthermore, component (D) is preferably an acrylic copolymer obtained by copolymerizing specific monomer X, an alkyl acrylate or alkyl methacrylate, with a monomer having a hydroxy group.

A simple method for synthesizing an acrylic copolymer in which a monomer having a hydroxy group is further copolymerized with specific monomer X, an alkyl acrylate or alkyl methacrylate ester, is to copolymerize specific monomer X with at least one monomer selected from monomers having a hydroxy group.

Examples of monomers having a hydroxy group include 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, 6-hydroxyhexyl acrylate, 6-hydroxyhexyl methacrylate, 8-hydroxyoctyl acrylate, 8-hydroxyoctyl methacrylate, 10-hydroxydecyl acrylate, 10-hydroxydecyl 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-acryloyloxy-6-hydroxynorbornene-2-carboxylic-6-lactone, 5-methacryloyloxy-6-hydroxynorbornene-2-carboxylic-6-lactone, etc.

Among these, 4-hydroxybutyl acrylate and 4-hydroxybutyl methacrylate are particularly preferred.

Furthermore, in the present invention, when obtaining specific copolymer D, in addition to specific monomer X and a monomer having a hydroxy group, a monomer (other monomer) that is copolymerizable with the specific monomer but does not have the crosslinkable group can be used in combination.

Specific examples of such other monomers include specific monomer X, as well as acrylic acid ester compounds or methacrylic acid ester compounds having a structure different from that of the monomer having a hydroxy group, maleimide compounds, acrylamide compounds, acrylonitrile, maleic anhydride, styrene compounds, and vinyl compounds.

Specific examples of the other monomers are listed below, but the present invention is not limited to these.
Examples of acrylic acid ester compounds having a structure different from that of the specific monomer X or the like include benzyl acrylate, naphthyl acrylate, anthryl acrylate, anthrylmethyl acrylate, phenyl acrylate, phenoxyethyl acrylate, glycidyl acrylate, 2,2,2-trifluoroethyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, and 8-ethyl-8-tricyclodecyl acrylate.

Methacrylic acid ester compounds having a structure different from that of the specific monomer X, etc., include, for example, benzyl methacrylate, naphthyl methacrylate, anthryl methacrylate, anthrylmethyl methacrylate, phenyl methacrylate, phenoxyethyl methacrylate, glycidyl methacrylate, 2,2,2-trifluoroethyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl-2-adamantyl methacrylate, γ-butyrolactone methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, and 8-ethyl-8-tricyclodecyl methacrylate.

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

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

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

In the polymer of component (D), the abundance ratio of the unit structure represented by formula (X) is preferably 45 mol % to 95 mol %, more preferably 55 mol % to 90 mol %, and even more preferably 70 mol % to 90 mol %, based on the total amount of the polymer.
That is, the amount of specific monomer X used to obtain specific copolymer D, which is component (D), is preferably 45 mol % to 95 mol %, more preferably 55 mol % to 90 mol %, and even more preferably 70 mol % to 90 mol %, based on the total amount of all monomers used to obtain specific copolymer D, which is component (D).

Furthermore, from the viewpoint of strengthening the adhesion between the film and the substrate through sufficient reaction with component (B), the total amount of hydroxyl group-containing monomers used in component (D) is preferably 5 mol % to 30 mol % based on the total amount of all monomers used to obtain specific copolymer D, which is component (D).

The method for obtaining specific copolymer D, an example of component (D), is not particularly limited. For example, it can be obtained by a polymerization reaction at a temperature of 50°C to 130°C in a solvent containing specific monomer X, a monomer having a hydroxy group, and optionally other monomers (other monomers), a polymerization initiator, etc. The solvent used is not particularly limited, as long as it dissolves the monomer represented by formula X above, the monomer having a hydroxy group, optionally other monomers (other monomers), and the polymerization initiator, etc. Specific examples of solvents used in the polymerization reaction are described in the section below under "Solvent."

The acrylic polymer, an example of component (D), obtained by the above method is usually in the form of a solution dissolved in a solvent, and can be used as is as a solution of component (D) in the present invention.

Furthermore, the solution of the acrylic polymer, an example of component (D), obtained by the above method can be reprecipitated by pouring it into diethyl ether, water, or the like while stirring. The resulting precipitate can then be filtered and washed, and then dried at room temperature or by heating under atmospheric or reduced pressure to obtain a powder of specific copolymer D, component (D). The above-mentioned procedure can remove the polymerization initiator and unreacted monomers that coexist with specific copolymer D, component (D), resulting in a purified powder of specific copolymer D, an example of component (D). If sufficient purification cannot be achieved in a single procedure, the obtained powder can be redissolved in a solvent and the above-mentioned procedure can be repeated.

In the cured film-forming composition of the present invention, the specific copolymer D of component (D) may be used in powder form, or in solution form in which the purified powder is redissolved in a solvent described below.

Furthermore, in the cured film-forming composition of the present invention, the component (D) may be a mixture of two or more of the specific copolymers D shown as examples of the component (D).
The acrylic polymer, which is an example of component (D), preferably has a weight-average molecular weight of 3,000 to 200,000, more preferably 4,000 to 150,000, and even more preferably 5,000 to 100,000. If the weight-average molecular weight is too high, exceeding 200,000, the solubility in solvents may decrease, resulting in poor handling, while if the weight-average molecular weight is too low, less than 3,000, the polymer may not cure sufficiently during heat curing, resulting in poor solvent resistance and heat resistance.

The content of component (D) in the cured film-forming composition of the present invention is preferably 10 to 500 parts by mass, more preferably 20 to 300 parts by mass, and even more preferably 30 to 200 parts by mass, based on 100 parts by mass of the low molecular weight compound having a photoalignable group and a thermally crosslinkable group (component (A)).

[(E) component]
The component (E) contained in the cured film-forming composition of this embodiment is inorganic fine particles that have been surface-modified with a group that does not have a (meth)acrylic group.
The inorganic fine particles of component (E) include silica particles with a primary particle diameter of 1 nm to 200 nm, which are surface-modified with a group that does not have a (meth)acrylic group.In particular, from the viewpoint of the storage stability of the varnish, silica particles surface-modified with at least one silane coupling agent are preferred.Furthermore, from the viewpoint of not affecting the liquid crystal alignment, silica particles with a primary particle diameter of 1 nm to 100 nm or 20 nm to 100 nm that are surface-modified with a silane coupling agent are preferred.

The silane coupling agent used to modify the surface of the silica particles of component (E) of the cured film-forming composition of the present invention may be one that does not have a (meth)acrylic group, and examples thereof include methyltrimethoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, isopropyltrimethoxysilane, n-butyltrimethoxysilane, isobutyltrimethoxysilane, n-pentyltrimethoxysilane, cyclopentyltrimethoxysilane, n-hexyltrimethoxysilane, cyclohexyltrimethoxysilane, isooctyltrimethoxysilane, phenyltrimethoxysilane, p-tolyltrimethoxysilane, benzyltrimethoxysilane, 1-naphthyltrimethoxysilane, trimethoxy[3-(phenylamino)propyl]silane, [3-(N,N- [dimethylamino)propyl]trimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 8-(2-aminoethylamino)octyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatopropyltrimethoxysilane, tris[3-(trimethoxysilyl)propyl]isocyanurate, methyltriethoxysilane, ethyltriethoxysilane, n-propyltriethoxysilane, isopropyltriethoxysilane, n-butyltriethoxysilane, isobutyltriethoxysilane, n-pentyltriethoxysilane, cyclopentyltriethoxysilane, n-hexyltriethoxysilane, cyclohexyltriethoxysilane, isooctyltriethoxysilane Sisilane, trialkoxysilanes such as phenyltriethoxysilane, p-tolyltriethoxysilane, benzyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltriethoxysilane, and tris[3-(triethoxysilyl)propyl]isocyanurate, dimethyldimethoxysilane, diethyldimethoxysilane, diisobutyldimethoxysilane, cyclopentylmethyldimethoxysilane, dicyclopentyldimethoxysilane, cyclohexylmethyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldimethoxysilane, di-p-tolyldimethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-mercaptopropylmethyldimethoxysilane Dialkoxysilanes such as dimethyldiethoxysilane, diethyldiethoxysilane, diisobutyldiethoxysilane, cyclopentylmethyldiethoxysilane, dicyclopentyldiethoxysilane, cyclohexylmethyldiethoxysilane, phenylmethyldiethoxysilane, diphenyldiethoxysilane, di-p-tolyldiethoxysilane, 3-(2-aminoethylamino)propylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, and 3-mercaptopropylmethyldiethoxysilane; monoalkoxysilanes such as trimethylmethoxysilane, triethylmethoxysilane, phenyldimethylmethoxysilane, diphenylmethylmethoxysilane, and triphenylmethoxysilane; and polyfunctional silane coupling agents.

Silane coupling agents can be used alone or in combination of two or more.

When surface-modifying silica particles using a silane coupling agent, the amount of the silane coupling agent used is preferably 0.1 to 2.0 mmol, more preferably 0.5 to 2.0 mmol, and even more preferably 0.5 to 1.7 mmol, per 1 g of silica particles.

By using an amount of silane coupling agent greater than 0.1 millimoles, the affinity and adhesion between the surface of the silica particles and the organic resin are sufficient, the transmittance of the cured product and molded article obtained from the cured film-forming composition of the present invention does not decrease, and cracks can be prevented from occurring at the base of the cured product and molded article after the development process using an organic solvent. By using an amount of silane coupling agent less than 2.0 millimoles, the silane coupling agent does not become excessive relative to the silica particles, and no silane coupling agent is left unused in the surface modification of the silica particles, allowing the storage stability and mechanical properties of the cured product and molded article to be maintained.

In the cured film-forming composition of the present invention, the silica particles of component (E) have a primary particle diameter of, for example, 1 nm to 200 nm. Here, primary particles are particles that make up the powder, and particles formed by agglomeration of these primary particles are called secondary particles. The primary particle diameter can be calculated from the relationship D = 6/(ρS), which holds between the specific surface area (surface area per unit mass) S of the silica particles measured by gas adsorption (BET) method, the density ρ of the silica particles, and the primary particle diameter D. The primary particle diameter calculated from this relationship is the average particle diameter, which is the diameter of the primary particles. Using particles with a primary particle diameter greater than 1 nm can suppress silica particle aggregation and improve storage stability. Using particles with a primary particle diameter smaller than 200 nm can improve the transparency of the cured product and molded article.

The silica particles of component (E) can be obtained by reacting surface-unmodified silica particles with the silane coupling agent using any of a variety of known methods. For example, it is preferable to use the surface-unmodified silica particles in the form of a dispersion of the silica particles in an organic solvent (organosilica sol).

The organosilica sol may be a commercially available water-dispersed silica sol in which the water is replaced with an organic solvent using known methods such as reduced pressure distillation or ultrafiltration, or a commercially available powdered silica particle dispersed in an organic solvent.

The silica solids concentration in the organosilica sol is not particularly limited, but is generally preferably 60% by mass or less.

The content of component (E) in the cured film-forming composition of the present invention is preferably 3 to 60 parts by mass, more preferably 3 to 45 parts by mass, and even more preferably 5 to 30 parts by mass, relative to 100 parts by mass of the total amount of components (A), (B), (C), (D), and (F) described below contained in the cured film-forming composition. If the content of component (E) is less than 3 parts by mass, the heat resistance of the cured product and molded article obtained from the cured film-forming composition may be deteriorated. If the content of component (E) is more than 60 parts by mass, haze may occur in the cured product and molded article, and the transmittance may be reduced.

The component (E) may be used singly or in combination of two or more. For example, multiple silica particles with different primary particle sizes may be combined, or multiple silica particles with different types and amounts of silane coupling agent used for surface modification may be combined.

[Component (F)]
The component (F) contained in the cured film-forming composition of the present embodiment is a compound having a hydroxy group and a (meth)acrylic group.

The compound of component (F) preferably has one or more hydroxy groups and one or more (meth)acrylic groups.

When a cured film formed from the cured film-forming composition of this embodiment containing component (F) is used as an alignment material, the polymerizable functional groups of the polymerizable liquid crystal and the cross-linking reaction sites of the alignment material can be covalently linked to improve adhesion between the alignment material and the polymerizable liquid crystal layer. As a result, the retardation material of this embodiment, which is formed by laminating cured polymerizable liquid crystal on the alignment material of this embodiment, can maintain strong adhesion even under high-temperature and high-humidity conditions and exhibit high durability against peeling, etc.

The content of component (F) in the cured film-forming composition of this embodiment is preferably 1 to 150 parts by mass, and more preferably 1 to 70 parts by mass, based on 100 parts by mass of the low molecular weight compound having a photoalignable group and a thermally crosslinkable group, which is component (A).

Furthermore, in the cured film-forming composition of this embodiment, component (F) may be a mixture of multiple types of compounds of component (F).

Below are preferred examples of compounds for component (F). Note that compounds for component (F) are not limited to the following compound examples.

(In the above formula, R ¹¹¹ represents a hydrogen atom or a methyl group, s represents an integer of 1 to 10, and m, n, o, p, q, and r each independently represent an integer of 0 to 6.)

[(G) component]
The cured film-forming composition of the present invention further contains a crosslinking catalyst as a component (G) in addition to the above-described components (A), (B), (C), (D), (E), and (F).

The crosslinking catalyst component (G) can be, for example, an acid or a thermal acid generator. Component (G) is effective in accelerating the thermal curing reaction when forming a cured film from the cured film-forming composition of the present invention (i.e., the composition that forms the cured film on the surface of the optical film of the present invention, as described below).

When an acid or thermal acid generator is used as component (G), component (G) is not particularly limited as long as it is a sulfonic acid group-containing compound, hydrochloric acid or its salt, or a compound that generates an acid upon thermal decomposition during pre-baking or post-baking, i.e., a compound that generates an acid upon thermal decomposition at a temperature of 60°C to 250°C.

Such compounds include, for example, sulfonic acids such as hydrochloric acid, methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, butanesulfonic acid, pentanesulfonic acid, octanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, camphorsulfonic acid, trifluoromethanesulfonic acid, p-phenolsulfonic acid, 2-naphthalenesulfonic acid, mesitylenesulfonic acid, p-xylene-2-sulfonic acid, m-xylene-2-sulfonic acid, 4-ethylbenzenesulfonic acid, 1H,1H,2H,2H-perfluorooctanesulfonic acid, perfluoro(2-ethoxyethane)sulfonic acid, pentafluoroethanesulfonic acid, nonafluorobutane-1-sulfonic acid, dodecylbenzenesulfonic acid, 1,2-ethanedisulfonic acid, and methanesulfonic anhydride, as well as hydrates and salts thereof.

Furthermore, examples of compounds that generate acid when heated (by thermal decomposition) include bis(tosyloxy)ethane, bis(tosyloxy)propane, bis(tosyloxy)butane, p-nitrobenzyl tosylate, o-nitrobenzyl tosylate, 1,2,3-phenylene tris(methylsulfonate), p-toluenesulfonic acid pyridinium salt, p-toluenesulfonic acid morpholinium salt, p-toluenesulfonic acid ethyl ester, p-toluenesulfonic acid propyl ester, p-toluenesulfonic acid butyl ester, p-toluenesulfonic acid isobutyl ester, p-toluenesulfonic acid methyl ester, p-toluenesulfonic acid phenethyl ester, cyanomethyl p-toluenesulfonate, 2,2,2-trifluoroethyl p-toluenesulfonate, 2-hydroxybutyl p-tosylate, N-ethyl-4-toluenesulfonamide, and compounds represented by the following formulas [TAG-1] to [TAG-41].

The (G) component is commercially available, and examples include TA-100, TA-100FG, IK-1, and IK-1FG (all manufactured by San-Apro Co., Ltd.), San-Aid (registered trademark) SI-B2A, San-Aid (registered trademark) SI-B7, San-Aid (registered trademark) SI-B3A, San-Aid (registered trademark) SI-B3, San-Aid (registered trademark) SI-B5, San-Aid (registered trademark) SI-B4, San-Aid (registered trademark) SI-150, San-Aid (registered trademark) SI-110, San-Aid (registered trademark) SI-60, San-Aid (registered trademark) SI-80, and San-Aid (registered trademark) SI-100 (all manufactured by Sanshin Chemical Industry Co., Ltd.).

The content of component (G) in the cured film-forming composition of the present invention is preferably 0.01 to 100 parts by weight, more preferably 1 to 100 parts by weight, even more preferably 10 to 100 parts by weight, and particularly preferably 20 to 80 parts by weight, per 100 parts by weight of component (A). By ensuring that the content of component (G) is 0.01 parts by weight or more, sufficient thermosetting properties and solvent resistance can be imparted, and high sensitivity to light exposure can also be imparted. Furthermore, by ensuring that the content is 100 parts by weight or less, the storage stability of the cured film-forming composition can be improved.

[Other additives]
The cured film-forming composition according to an embodiment of the present invention may contain other additives as long as the effects of the present invention are not impaired.
Other additives that may be included include, for example, a sensitizer, which is effective in accelerating the photoreaction when forming a cured film on the surface of the optical film of the present invention.

Sensitizers include derivatives of benzophenone, anthracene, anthraquinone, and thioxanthone, as well as nitrophenyl compounds. Of these, the benzophenone derivative N,N-diethylaminobenzophenone and the nitrophenyl compounds 2-nitrofluorene, 2-nitrofluorenone, 5-nitroacenaphthene, 4-nitrobiphenyl, 4-nitrocinnamic acid, 4-nitrostilbene, 4-nitrobenzophenone, and 5-nitroindole are particularly preferred.

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

In an embodiment of the present invention, when a sensitizer is used, the proportion used is preferably 1 to 100 parts by mass, and more preferably 10 to 80 parts by mass, per 100 parts by mass of component (A). If this proportion is too small, the effect of the sensitizer may not be fully achieved, and if it is too large, the transmittance of the cured film formed may decrease, or the coating film may become rough.

In addition, the cured film-forming composition of this embodiment of the present invention may contain other additives such as silane coupling agents, surfactants, rheology modifiers, pigments, dyes, storage stabilizers, antifoaming agents, and antioxidants, as long as the effects of the present invention are not impaired.

[solvent]
The cured film-forming composition according to the embodiment of the present invention can be used in the form of a solution dissolved in a solvent. The solvent used in this case is one that dissolves the components (A), (B), (C), (D), (E), (F), and (G), and, if necessary, other additives, and the type and structure of the solvent are not particularly limited as long as it has the ability to dissolve the components.

Specific examples of solvents include 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, propylene glycol propyl ether acetate, cyclopentyl methyl ether, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, 3-methyl-2-pentanone, 2-pentanone, 2-heptanone, Examples of suitable solvents include acetone, γ-butyrolactone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, n-propyl acetate, isopropyl acetate, methanol, ethanol, n-propanol, isopropanol, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone.

Solvents are commercially available, and examples include Neoethanol (registered trademark) PM, Neoethanol (registered trademark) MIP, Neoethanol (registered trademark) IPM, Neoethanol (registered trademark) IPE, Neoethanol (registered trademark) PHI, Neoethanol (registered trademark) MHI, Neoethanol (registered trademark) PIP, Neoethanol (registered trademark) HIMTE, Neoethanol (registered trademark) PHM, Neoethanol (registered trademark) IPME, and Neoethanol (registered trademark) P-7 (all manufactured by Taishin Chemical Co., Ltd.).

These solvents can be used alone or in combination of two or more. Of these solvents, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, methyl ethyl ketone, cyclohexanone, 2-heptanone, propylene glycol propyl ether, propylene glycol propyl ether acetate, ethyl acetate, ethyl lactate, butyl lactate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, and Neoethanol (registered trademark) IPM are more preferred due to their excellent film-forming properties and high safety.

<Preparation of Cured Film-Forming Composition>
The cured film-forming composition of the present invention (i.e., the composition that forms the cured film on the surface of the optical film of the present invention) comprises, as described above, component (A) a low molecular weight compound having a photoalignment group and a thermally crosslinkable group (photoalignment component), component (B) a crosslinker having an N-hydroxymethyl group or an N-alkoxymethyl group, component (C) a polymer having 60 mol % or more of all repeating units containing repeating units having a hydroxy group, component (D) a polymer having 45 mol % or more of all repeating units of repeating units represented by formula (X) and having repeating units containing a hydroxy group, component (E) inorganic fine particles that are surface-modified with a group that does not contain a (meth)acrylic group, component (F) a low molecular weight compound having both a (meth)acrylic group and a hydroxy group, and component (G) a crosslinking catalyst, and in one embodiment, further contains a solvent, and the above-mentioned components can be dissolved in the solvent. The cured film-forming composition of the present invention can also contain other additives as long as they do not impair the effects of the present invention.

Preferred examples of the cured film-forming composition of the present invention are as follows:

A cured film-forming composition comprising: component (A); 100 to 2,000 parts by weight of component (B) based on 100 parts by weight of the compound that is component (A); 50 to 1,500 parts by weight of component (C) based on 100 parts by weight of component (A); 10 to 500 parts by weight of component (D) based on 100 parts by weight of the low molecular weight compound that has a photoalignable group and a thermally crosslinkable group that is component (A); 3 to 60 parts by weight of component (E) based on 100 parts by weight of the total of components (A), (B), (C), (D), and (F); 1 to 150 parts by weight of component (F) based on 100 parts by weight of component (A); 0.01 to 100 parts by weight of component (G) based on 100 parts by weight of component (A); and a solvent.

The blending ratios, preparation method, etc. when the cured film-forming composition of the present invention is used as a solution (so-called varnish) will be described in detail below.
The solid content of the cured film-forming composition of the present invention is not particularly limited as long as each component is uniformly dissolved in the solvent, but is preferably 1 to 80% by mass, more preferably 2 to 60% by mass, and even more preferably 3 to 40% by mass. Here, the solid content refers to all components of the cured film-forming composition excluding the solvent.

The method for preparing the cured film-forming composition of the present invention is not particularly limited. Examples of preparation methods include mixing components (A), (B), (C), (E), (F), and (G) in a predetermined ratio with a solution of component (D) dissolved in a solvent to form a homogeneous solution, or adding and mixing other additives as needed at an appropriate stage in this preparation method. Furthermore, component (G) may be added immediately before use to enhance the storage stability of the varnish.

In preparing the cured film-forming composition of the present invention, as described above, the solution of specific copolymer D (component (D)) obtained by polymerization in a solvent can be used as is. In this case, for example, components (A), (B), (C), (E), (F), etc. are added to a solution of component (D) obtained by copolymerizing the aforementioned monomer having a hydroxy group, monomer X, and, if desired, other monomers to form a homogeneous solution. At this time, additional solvent may be added to adjust the concentration. In this case, the solvent used in the production process of component (D) and the solvent used to adjust the concentration of the cured film-forming composition may be the same or different.

It is also preferable to filter the prepared solution of the cured film-forming composition using a filter with a pore size of approximately 0.2 μm before using it to form a cured film.

<Optical film>
The optical film of the present invention is preferably obtained by applying the above-mentioned cured film-forming composition (a solution thereof) onto a film (for example, a resin film such as a triacetyl cellulose (TAC) film, a cycloolefin polymer film, a polyethylene terephthalate film, or an acrylic film) substrate by bar coating, spin coating, flow coating, roll coating, slit coating, spin coating followed by slit coating, inkjet coating, printing, or the like to form a coating film, and then heating and drying the coating on a hot plate, in an oven, or the like to form a cured film.

As the acrylic film, a film made of a copolymer whose main monomer component is alkyl methacrylate ester and/or alkyl acrylate ester can be used as appropriate.

It is preferable that the film used as the substrate has a thickness of 20 μm to 100 μm.

The conditions for heat drying are such that, when using a cured film as a liquid crystal alignment film as described below, the curing reaction proceeds to such an extent that the components of the liquid crystal alignment film do not dissolve into the polymerizable liquid crystal solution that is applied on top of it. For example, a heating temperature and heating time selected appropriately from the ranges of 50°C to 99°C and 0.4 to 60 minutes are used. The heating temperature and heating time are preferably 60°C to 95°C and 0.5 to 10 minutes.

The thickness of the cured surface film in the optical film of the present invention is, for example, 0.05 μm to 10 μm, and can be selected appropriately taking into consideration the unevenness and optical and electrical properties of the film used as the substrate.

The optical film of the present invention produced in this manner can be irradiated with polarized UV light, causing the cured film formed on the substrate to function as a liquid crystal alignment film, i.e., as a component for aligning compounds with liquid crystallinity, including polymerizable liquid crystals, and thus the optical film can be used as an alignment material.

Polarized UV irradiation typically uses ultraviolet to visible light with wavelengths between 150 nm and 450 nm, and is performed by irradiating the material with linearly polarized light from a vertical or oblique direction at room temperature or in a heated state.

In the alignment material of the present invention, the cured film that becomes the liquid crystal alignment film is solvent-resistant and heat-resistant. Therefore, after applying a retardation material made of a polymerizable liquid crystal solution onto this alignment material, the retardation material can be converted to a liquid crystal state by heating it to the phase transition temperature of the liquid crystal, and then oriented on the alignment material. Then, by curing the retardation material in the desired alignment state, a retardation material with a layer having optical anisotropy can be formed.

For example, liquid crystal monomers having polymerizable groups and compositions containing them are used as retardation materials. In the present invention, the substrate of the alignment material is a film, so the retardation material of the present invention is useful as a retardation film. Retardation materials that form such retardation materials are in a liquid crystal state and can assume orientation states such as horizontal alignment, cholesteric alignment, vertical alignment, and hybrid alignment on the alignment material, and each can be used depending on the required retardation characteristics.

Furthermore, when producing a patterned retardation material for use in 3D displays, the cured film on the surface of the optical film of the present invention is exposed to polarized UV light through a line-and-space pattern mask at an angle of, for example, +45 degrees from a predetermined reference. The mask is then removed and the cured film is exposed to polarized UV light at an angle of -45 degrees with a smaller exposure dose. This allows the cured film on the film surface to become a liquid crystal alignment film with two types of liquid crystal alignment domains that differ in their liquid crystal alignment control directions, and the optical film can be made into an alignment material with two types of liquid crystal distribution domains. A retardation material made of a polymerizable liquid crystal solution is then applied to the alignment material, and the retardation material is then placed in a liquid crystal state by heating to the liquid crystal phase transition temperature. The polymerizable liquid crystal in the liquid crystal state is oriented on the alignment material with the two types of liquid crystal alignment domains formed, forming alignment states corresponding to each liquid crystal alignment domain. The retardation material with this alignment state is then cured as is to fix the above-mentioned alignment state, thereby obtaining a patterned retardation material with two types of retardation domains with different retardation characteristics, each arranged in a regular pattern.

The optical film of the present invention can also be used as a liquid crystal alignment film for a liquid crystal display element. For example, the optical film of the present embodiment formed as described above can be used to manufacture a liquid crystal display element in which the liquid crystal is aligned by laminating two optical films together via a spacer so that the alignment materials of the two optical films face each other, and then injecting liquid crystal between the substrates.
Therefore, the optical film of the present invention can be suitably used in the production of various retardation materials (retardation films), liquid crystal display elements, and the like.

The present invention will be explained in more detail below using examples, but the present invention is not limited to these examples.

[Abbreviations used in the Examples]
The abbreviations used in the following examples have the following meanings.

<Raw materials>
BMAA: N-butoxymethylacrylamide 4HBA: 4-hydroxybutyl acrylate MMA: methyl methacrylate AIBN: α,α'-azobisisobutyronitrile MAIB: 2,2'-azobis(isobutyrate) dimethyl

<Solvent>
PM: Propylene glycol monomethyl ether MEK: Methyl ethyl ketone IPM: Neoethanol (registered trademark) IPM (manufactured by Taishin Chemical Co., Ltd.)
EA: ethyl acetate CPN: cyclopentanone

<Component (A): Low-Molecular-Weight Compound Having a Photoalignable Group and a Thermally Crosslinkable Group>
M6CA:

6CAM:

<Inorganic fine particle component>
E-1 (Alkylsilyl-modified organosilica sol) (corresponding to component (E))
E-2 (organosilica sol having (meth)acrylic groups)
E-3 (organosilica sol having (meth)acrylic groups)

<Component (F): Low-Molecular-Weight Compound Having Both a (Meth)acrylic Group and a Hydroxy Group>
PE-200: Blemmer (registered trademark) PE-200 (manufactured by NOF Corporation) (polyethylene glycol monomethacrylate)
CHDMMA: 1,4-cyclohexanedimethanol monoacrylate (manufactured by Shinryo Corporation)

<(G) component: crosslinking catalyst>
CSA: (±)-10-camphorsulfonic acid

<Measurement of weight average molecular weight>
Apparatus: GPC apparatus (HLC-8320) manufactured by Tosoh Corporation
Column: Shodex (registered trademark) Asahipak GF-310HQ, GF-510HQ, and GF-710HQ manufactured by Showa Denko K.K.
Column oven: 40°C
Flow rate: 0.6 ml/min Eluent: N,N-dimethylformamide Standard sample: polystyrene

<Synthesis of component (B)>
<Synthesis Example 1>
BMAA (145.5 g) and AIBN (4.6 g) as a polymerization catalyst were dissolved in PM (150.1 g), and this solution was then added dropwise over 30 minutes to a flask containing PM (200.1 g) maintained at 80°C. After completion of the addition, the mixture was reacted at 80°C for 5 hours to obtain an acrylic polymer solution (PB-1) (solids concentration 30% by mass). The weight average molecular weight Mw of the obtained acrylic polymer was 23,000.

<Synthesis of Component (C)>
<Synthesis Example 2>
4HBA (197.0 g) and MAIB (3.1 g) as a polymerization catalyst were dissolved in PM (133.4 g), and this solution was then added dropwise over 2 hours to a flask containing PM (166.8 g) maintained at 70°C. After completion of the addition, the mixture was allowed to react at 70°C for 18 hours to obtain an acrylic polymer solution (PC-1) (solids concentration 40% by mass). The weight average molecular weight Mw of the obtained acrylic polymer was 22,700.

<Synthesis of Component (D)>
<Synthesis Example 3>
MMA (84.4 g), 4HBA (13.5 g), and MAIB (2.2 g) as a polymerization catalyst were dissolved in PM (150.1 g), and this solution was then added dropwise over 2 hours to a flask containing PM (250.2 g) maintained at 70°C. After completion of the addition, the mixture was allowed to react at 70°C for 18 hours to obtain an acrylic copolymer solution (PD-1) (solids concentration 20% by mass). The weight average molecular weight Mw of the resulting acrylic copolymer was 38,900.

<Preparation of Composition>
<Preparation Example 1>
(A) component M6CA (0.080 g), (B) component 30 mass% PM solution of the acrylic polymer obtained in Synthesis Example 1 (PB-1) (1.093 g), (C) component 40 mass% PM solution of the acrylic polymer obtained in Synthesis Example 2 (PC-1) (0.520 g), (D) component 20 mass% PM solution of the acrylic copolymer obtained in Synthesis Example 3 (PD-1) (0.400 g), (E) component E-1 (0.267 g), (F) component PE-200 (0.024 g), and PM (7.614 g) were added, stirred for 2 hours, and dissolution was confirmed visually. Thereafter, by filtration through a glass filter having a pore size of 1.0 μm, a composition (A-1) having a solids concentration of 8.0 mass% was prepared.

<Preparation Examples 2 to 8>
Compositions (A-2) to (A-4) and (C-1) to (C-5) were prepared in the same manner as in Preparation Example 1, except that the types and amounts of each component shown in Table 1 below were used.

In Table 1, the numbers in parentheses for components (A) through (F) and other components indicate the mass ratio of each component (excluding the solvent if diluted with a solvent).

<Preparation of crosslinking catalyst solution>
<Preparation Example 10>
CSA (2.0 g) as a crosslinking catalyst and PM (18.0 g) as a solvent were added, stirred for 1 hour, and dissolved visually. The solution was filtered through a filter with a pore size of 0.2 μm to prepare a crosslinking catalyst solution (G-1).

<Preparation Example 11>
<Preparation of polymerizable liquid crystal solution for horizontal alignment>
Paliocolor (registered trademark) LC-242 (manufactured by BASF Japan Ltd.) (19.3 g), which is a polymerizable liquid crystal for horizontal alignment, Omnirad (registered trademark) 907 (manufactured by IGM Resins BV (formerly BASF Japan Ltd.)) (0.6 g) as a photoradical initiator, and BYK (registered trademark) -361N (manufactured by BYK Japan K.K.) (0.1 g) as a leveling agent were added, and CPN (80 g) was further added as a solvent. The mixture was stirred for 2 hours, and dissolution was confirmed visually. The mixture was then filtered through a PTFE filter with a pore size of 0.2 μm to obtain a 20% by mass polymerizable liquid crystal solution (LC-1).

<Preparation of Cured Film-Forming Composition>
<Example 1-1>
A-1 (2.00 g) obtained in Preparation Example 1, G-1 (0.08 g) obtained in Preparation Example 10, EA (0.90 g) as a dilution solvent, and IPM (0.90 g) were added and stirred for 15 hours to obtain a cured film-forming composition (AL-1).

<Examples 1-2 to 1-4>
Cured film-forming compositions (AL-2) to (AL-4) were obtained in the same manner as in Example 1-1, except that A-2 to A-4 were used instead of A-1.

<Comparative Examples 1-1 to 1-5>
Cured film-forming compositions CL-1 to CL-5 were obtained in the same manner as in Example 1-1, except that C-1 to C-5 were used instead of A-1.

<Formation of Liquid Crystal Alignment Film and Preparation of Retardation Film>
<Example 2-1>
The cured film-forming composition (AL-1) obtained in Example 1-1 was applied to an acrylic film substrate using a bar coater to a wet film thickness of 6 μm. Heat drying was performed in a heat circulation oven at 90°C for 1 minute to form a cured film on the film. The surface of this cured film was then irradiated vertically with linearly polarized light having a wavelength of 313 nm at an exposure dose of 20 mJ/ ^cm² to form a liquid crystal alignment film. Polymerizable liquid crystal solution LC-1 for horizontal alignment was applied to the liquid crystal alignment film using a bar coater to a wet film thickness of 8 μm. Next, heat drying was performed in an oven at 90°C for 1 minute, and then the polymerizable liquid crystal was cured by vertical irradiation with unpolarized light having a wavelength of 365 nm at an exposure dose of 500 mJ/ ^cm² under a nitrogen atmosphere to produce a retardation film (S-1).

<Examples 2-2 to 2-4, Comparative Examples 2-1 to 2-5>
The same procedure as in Example 2-1 was carried out except that AL-2 to AL-4 or CL-1 to CL-5 were used instead of the cured film-forming composition AL-1, to produce retardation films (S-2) to (S-4) and (R-1) to (R-5), as shown in the table below.

[Orientation evaluation]
The retardation films S-1 to S-4 and R-1 to R-5 obtained in Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-5 were sandwiched between a pair of polarizing plates, and the state of expression of retardation properties under crossed Nicols was visually observed. The films in which retardation was expressed without defects were evaluated as "A," and the films in which retardation was not expressed were evaluated as "C." The results are shown in Table 3.

[Cleaning evaluation]
The retardation films S-1 to S-4 and R-1 to R-5 obtained in Examples 2-1 to 2-4 and Comparative Examples 2-1 to 2-5 were sandwiched between a pair of polarizing plates, and the state of expression of retardation characteristics under crossed Nicols was visually observed. Those without any repelling of the liquid crystal layer in the central 50 x 50 mm range were evaluated as "A", those with several to 20 repellings of the liquid crystal layer were evaluated as "B", and those with more than 20 repellings of the liquid crystal layer were evaluated as "C". The results are shown in Table 3.

[Adhesion evaluation]
The retardation film on the substrate thus prepared was cut into 100 squares at 1 mm intervals in a grid pattern using a cutter knife, and Cellotape (registered trademark) (manufactured by Nichiban Co., Ltd., 24 mm wide) was firmly pressed onto the film, which was then peeled off in one go to measure the number of grids remaining on the substrate. The results were evaluated as "A" if all the grids remained, "B" if some of the grids peeled off, and "C" if all the grids peeled off. The results are shown in Table 3.

As is clear from the results in Table 3, none of the retardation films obtained in Examples 2-1 to 2-4 exhibited cissing and showed good alignment. Furthermore, it can be seen that the adhesion to the liquid crystal and the substrate was good. In contrast, in Comparative Examples 2-1 to 2-5, no good retardation films were obtained that satisfied all of the properties of alignment, cissing, and adhesion.
By using inorganic fine particles that have been surface-modified with groups that do not have (meth)acrylic groups as component (E), interaction with component (F), a low molecular weight compound that has both (meth)acrylic groups and hydroxyl groups, is suppressed, resulting in component (F) being ubiquitous on the surface and not hindering its function as an adhesion promoter, and it is thought that an alignment material with high adhesion to the liquid crystal layer can be obtained.

Films formed with the cured film of the present invention are extremely useful as liquid crystal alignment materials for liquid crystal display elements, and as alignment materials for forming optically anisotropic films provided inside or outside liquid crystal display elements, and are particularly suitable as materials for forming patterned retardation materials for 3D displays. Furthermore, they are also suitable as materials for forming cured films such as protective films, planarizing films, and insulating films in various displays such as thin-film transistor (TFT) liquid crystal display elements and organic EL elements, and are particularly suitable as materials for forming interlayer insulating films in TFT liquid crystal elements, protective films for color filters, or insulating films in organic EL elements.

Claims (9)

(A) a low molecular weight compound having a photoalignable group and a thermally crosslinkable group;
(B) a crosslinking agent having an N-hydroxymethyl group or an N-alkoxymethyl group;
(C) a polymer having 60 mol % or more of all repeating units containing a hydroxy group;
(D) A polymer having 45 mol % or more of repeating units represented by the following formula (X) based on all repeating units, and also having a repeating unit having a hydroxy group:
(E) inorganic fine particles whose surface has been modified with a group having no (meth)acrylic group;
A cured film-forming composition comprising: (F) a low molecular weight compound having both a (meth)acrylic group and a hydroxy group; and (G) a crosslinking catalyst.
(In the above formula, ^R1 represents a hydrogen atom or a methyl group, and ^R2 represents a linear or branched alkyl group having 1 to 5 carbon atoms.) The cured film-forming composition according to claim 1, wherein the photoalignable group of component (A) is a functional group having a structure that undergoes photodimerization or photoisomerization. The cured film-forming composition according to claim 1, wherein the photoalignable group of component (A) is a cinnamoyl group. The cured film-forming composition according to claim 1, wherein the photoalignable group of component (A) is a group having an azobenzene structure. The cured film-forming composition according to claim 1, wherein the crosslinking agent (B) is a polymer obtained by polymerizing a monomer selected from N-hydroxymethyl(meth)acrylamide and N-alkoxymethyl(meth)acrylamide compounds. A cured film obtained from the cured film-forming composition described in any one of claims 1 to 5. An optical film having the cured film described in claim 6. An alignment material formed using the cured film described in claim 6. A retardation material formed using the cured film according to claim 6 .