TWI868144B - Cured film forming composition, alignment material and phase difference material - Google Patents

Abstract

The subject of the present invention is to provide an alignment material and a cured film forming composition for obtaining the alignment material. The alignment material has excellent alignment sensitivity and not only excellent alignment uniformity, but also has resistance to solvents in liquid crystal solutions even in the form of a thin film, and can function as a protective layer for protecting a film substrate. The solution is a cured film forming composition, which contains: (A) a photo-alignment group and a compound of one substituent selected from the group consisting of a hydroxyl group, a carboxyl group and an amino group, (B) a polymer formed by polymerizing a monomer containing at least an N-alkoxymethyl (meth) acrylamide compound, and (C) a polymer formed by polymerizing a monomer containing at least an N-hydroxyalkyl (meth) acrylamide compound, and may further contain a crosslinking catalyst (D) and an adhesion enhancing component (E) as necessary. The cured film forming composition is used to form a cured film, and an alignment material is formed by using a photoalignment technique. A polymerizable liquid crystal is applied on the alignment material and cured to obtain a phase difference material.

Description

Cured film forming composition, alignment material and phase difference material

The present invention relates to a hardened film forming composition, an alignment material and a phase difference material.

In the case of a 3D display of a circularly polarized glasses type, a phase difference material is usually arranged on a display element such as a liquid crystal panel that forms an image. The phase difference material is a patterned phase difference material formed by regularly arranging two types of phase difference regions with different phase difference characteristics. Moreover, in the following, in this specification, the phase difference material patterned by arranging a plurality of phase difference regions with different phase difference characteristics is referred to as a patterned phase difference material.

The patterned phase difference material can be produced by optically patterning a phase difference material containing polymeric liquid crystal, as disclosed in Patent Document 1. The optical patterning of the phase difference material containing polymeric liquid crystal utilizes the well-known photo-alignment technology in the formation of the alignment material of the liquid crystal panel. That is, a coating film containing a photo-alignment material is provided on a substrate, and two types of polarized light with different polarization directions are irradiated thereon. Subsequently, a photo-alignment film is obtained as an alignment material in which two types of liquid crystal alignment regions with different alignment control directions of the liquid crystal have been formed. A solution-state phase difference material containing polymeric liquid crystal is coated on the photo-alignment film, thereby realizing the alignment of the polymeric liquid crystal. Thereafter, the aligned polymeric liquid crystal is hardened to form a patterned phase difference material.

The anti-reflection film of the organic EL display is composed of a linear polarizer and a 1/4 wavelength phase difference plate. The linear polarizer converts the external light toward the panel surface of the image display panel into linear polarization, and then converts it into circular polarization by the 1/4 wavelength phase difference plate. Here, although the external light formed by the circular polarization is reflected on the surface of the image display panel, the rotation direction of the polarization plane is reversed during the reflection. As a result, the reflected light is converted into linear polarization in the direction blocked by the linear polarizer by the 1/4 wavelength phase difference plate in the opposite direction to when it arrived, and then blocked by the linear polarizer. As a result, the outgoing light to the outside is significantly suppressed.

Regarding the 1/4 wavelength phase difference plate, Patent Document 2 has proposed a method of forming a 1/4 wavelength phase difference plate by combining a 1/2 wavelength plate and a 1/4 wavelength plate, and forming the optical film by using the anti-dispersion property. In the case of this method, a liquid crystal material using the positive dispersion property can be used in a wide wavelength range for color image display, and an optical film can be formed by using the anti-dispersion property.

In recent years, liquid crystal materials having anti-dispersion properties have been proposed as liquid crystal materials applicable to the phase difference layer (Patent Documents 3 and 4). If liquid crystal materials having such anti-dispersion properties are used, it is possible to replace the phase difference layer composed of two layers of a half-wave plate and a quarter-wave plate to form a quarter-wave plate, and instead to form a phase difference layer with a single layer while ensuring the anti-dispersion properties, and thereby to realize an optical film that can ensure the desired phase difference in a wide wavelength range with a simple structure.

An alignment layer is used to align liquid crystals. As methods for forming the alignment layer, there are known methods such as rubbing and photo-alignment. The photo-alignment method does not have the problems of the rubbing method, that is, it does not generate static electricity or dust, and is extremely useful in controlling the quantitative alignment process.

In the formation of alignment materials using the photo-alignment method, acrylic resins or polyimide resins having photodimerization sites such as cinnamyl groups and chalcone groups on the side chains are known as materials with photo-alignment properties. It has been reported that these resins show the ability to control liquid crystal alignment (hereinafter also referred to as liquid crystal alignment) by polarized UV irradiation (see Patent Documents 5 to 7).

In addition to the liquid crystal alignment ability, the alignment layer is also required to be solvent resistant. For example, the alignment layer may be exposed to heat or solvents during the manufacturing process of the phase difference material. If the alignment layer is exposed to a solvent, there is a concern that the liquid crystal alignment ability may be significantly reduced.

Therefore, for example, in Patent Document 8, in order to obtain a stable liquid crystal alignment ability, a liquid crystal alignment agent has been proposed, which contains: a polymer component having a structure capable of undergoing a crosslinking reaction due to light and a structure capable of undergoing a crosslinking reaction due to heat; and, a liquid crystal alignment agent, which contains: a polymer component having a structure capable of undergoing a crosslinking reaction due to light, and a compound having a structure capable of undergoing a crosslinking reaction due to heat. [Prior art document] [Patent document]

[Patent Document 1] Japanese Patent Publication No. 2005-49865 [Patent Document 2] Japanese Patent Publication No. 10-68816 [Patent Document 3] U.S. Patent No. 8119026 [Patent Document 4] Japanese Patent Publication No. 2009-179563 [Patent Document 5] Japanese Patent No. 3611342 [Patent Document 6] Japanese Patent Publication No. 2009-058584 [Patent Document 7] Japanese Patent Publication No. 2001-517719 [Patent Document 8] Japanese Patent No. 4207430

[The problem that the invention wants to solve]

As mentioned above, the phase difference material is composed of a layer of hardened polymerizable liquid crystal laminated on an alignment material, i.e., a photo-alignment film. Therefore, it is considered necessary to develop an alignment material that can have both excellent liquid crystal alignment and solvent resistance.

However, according to the inventors' review, it is known that acrylic resins having photodimerization sites such as cinnamyl or chalcone groups on the side chains cannot obtain sufficient properties when used to form phase difference materials. In particular, in order to irradiate these resins with polarized UV to form an alignment material, and use the alignment material to manufacture a phase difference material containing polymerizable liquid crystal, a huge amount of polarized UV exposure is required. The polarized UV exposure is more than the sufficient polarized UV exposure required to align the liquid crystal used in a normal liquid crystal panel (for example, about 30mJ/ ^cm2 ).

As a reason for the increase in polarized UV exposure, it can be cited that in the case of forming a phase difference material, unlike the liquid crystal used in a liquid crystal panel, the polymerizable liquid crystal is used in a solution state and is coated on the alignment material.

When attempting to use an acrylic resin or the like having a photodimerization site such as a cinnamoyl group on the side chain to form an alignment material and align the polymerizable liquid crystal, photocrosslinking due to the photodimerization reaction will occur in the acrylic resin or the like. Furthermore, until resistance to the polymerizable liquid crystal solution is exhibited, it is necessary to perform polarized light irradiation with a huge amount of exposure. In order to align the liquid crystal of the liquid crystal panel, it is usually sufficient to allow only the surface of the photoalignable alignment material to undergo a dimerization reaction. However, when attempting to use the above-mentioned conventional materials such as the acrylic resin to make the alignment material exhibit solvent resistance, it is necessary to allow the reaction to proceed to the interior of the alignment material, and a greater amount of exposure will be required. As a result, there is a problem that the alignment sensitivity of the conventional material becomes very small.

In order to make the resin of the above-mentioned conventional materials exhibit such solvent resistance, a technique of adding a crosslinking agent is known. However, it is known that after the heat curing reaction using the crosslinking agent, a three-dimensional structure is formed inside the formed coating film, and the photoreactivity decreases. In other words, the orientation sensitivity is greatly reduced, and even if the conventional material is added with a crosslinking agent, the desired effect cannot be obtained.

Furthermore, various organic solvents are used in liquid crystal inks, and as a substrate, a film with low resistance to organic solvents may be used. Therefore, for the reason of protecting the film, an alignment film with high solvent resistance is required.

In view of the above, a photo-alignment technology that can improve the alignment sensitivity of the alignment material and reduce the exposure amount of polarized UV light, and a cured film forming composition that can be used as a liquid crystal alignment agent for photo-alignment used to form the alignment material are required. In addition, a technology that can efficiently provide a phase difference material is required.

The purpose of the present invention is achieved based on the above knowledge and review results. That is, the purpose of the present invention is to provide a cured film forming composition that can be used as a liquid crystal alignment agent for photo-alignment, and the liquid crystal alignment agent for photo-alignment is used to provide an alignment material that not only has excellent alignment sensitivity, but also has excellent alignment uniformity, and even in the form of a thin film, it is still resistant to solvents in the liquid crystal solution, and can also function as a protective layer to protect the film substrate.

Other purposes and advantages of the present invention can be clearly understood from the following description. [Means for solving the problem]

The first aspect of the present invention is related to a hardened film forming composition, which is characterized by containing: (A) a compound having a photo-alignment group and a substituent selected from the group consisting of a hydroxyl group, a carboxyl group and an amino group, (B) a polymer formed by polymerizing a monomer containing at least an N-alkoxymethyl (meth) acrylamide compound, and (C) a polymer formed by polymerizing a monomer containing at least an N-hydroxyalkyl (meth) acrylamide compound.

In the first aspect of the present invention, the photo-alignment group of the component (A) is preferably a functional group of a structure that undergoes photodimerization or photoisomerization. In the first aspect of the present invention, the photo-alignment group of the component (A) is preferably a cinnamyl group. In the first aspect of the present invention, the photo-alignment group of the component (A) is preferably a group of an azobenzene structure. In the first aspect of the present invention, it is preferred to further contain a crosslinking catalyst as the component (D). In the first aspect of the present invention, it is preferred to further contain an adhesion-enhancing component as the component (E). In the first aspect of the present invention, the total amount of the components (B) and (C) is preferably 100 to 3000 parts by mass relative to 100 parts by mass of the component (A). In the first aspect of the present invention, the mass ratio of component (B) to component (C) is preferably 1:99 to 99:1. In the first aspect of the present invention, it is preferred to contain 0.01 to 10 parts by mass of component (D) relative to 100 parts by mass of the total amount of components (B) and (C).

The second aspect of the present invention is an alignment material, characterized in that it is obtained by using the cured film forming composition of the first aspect of the present invention.

The third aspect of the present invention is a phase difference material characterized by being formed using a cured film obtained from a cured film forming composition as in the first aspect of the present invention. [Effect of the invention]

According to the first aspect of the present invention, a cured film forming composition can be provided, which is used to provide an alignment material, which not only has excellent alignment sensitivity but also excellent alignment uniformity, and even in the form of a thin film, is resistant to solvents in a liquid crystal solution and can also function as a protective layer for protecting a film substrate.

According to the second aspect of the present invention, an alignment material can be provided, which not only has excellent alignment sensitivity but also excellent alignment uniformity. Even in the form of a thin film, it is still resistant to solvents in a liquid crystal solution and can also function as a protective layer to protect a film substrate.

According to the third aspect of the present invention, a phase difference material can be provided, which can be formed with high efficiency even on a film substrate and can be optically patterned.

＜Curing film forming composition＞

The cured film forming composition of the present invention contains: (A) a compound having a photo-alignment group and one substituent selected from the group consisting of a hydroxyl group, a carboxyl group and an amino group (hereinafter also described as a "low molecular photo-alignment component"), (B) a polymer formed by polymerizing a monomer containing at least an N-alkoxymethyl (meth) acrylamide compound, and (C) a polymer formed by polymerizing a monomer containing at least an N-hydroxyalkyl (meth) acrylamide compound. In addition to the components (A), (B) and (C), the cured film forming composition of the present invention may also contain a crosslinking catalyst (D) and a component for improving the adhesion of the cured film (E). In addition, other additives may be contained as long as they do not impair the effects of the present invention.

The following describes the details of each component. ＜Component (A)＞ The component (A) contained in the cured film forming composition of the present invention is a low molecular weight photo-alignment component as described above.

Furthermore, the low molecular weight photo-alignment component of component (A) is a compound having a photo-alignment group and a substituent selected from the group consisting of a hydroxyl group, a carboxyl group and an amino group. In the compound having a photo-alignment group and a substituent selected from the group consisting of a hydroxyl group, a carboxyl group and an amino group, as described above, the photo-alignment group reacts with light to form a hydrophobic photo-alignment part, and the hydroxyl group etc. constitute a hydrophilic thermal reaction part. Moreover, in the present invention, the photo-alignment group refers to a functional group of a structural part that undergoes photodimerization or photoisomerization.

The structural site that undergoes photodimerization refers to a site that forms a dimer due to light irradiation, and specific examples thereof include cinnamyl, chalcone, coumarin, anthracene, etc. Among them, cinnamyl is preferred because it has high transparency and photodimerization reactivity in the visible light region. In addition, the structural site that undergoes photoisomerization refers to a structural site that is converted into a cis-isomer and a trans-isomer due to light irradiation, and specific examples thereof include sites including azobenzene structure and stilbene structure. Among them, from the perspective of high reactivity, azobenzene structure is preferred. Compounds having a photo-alignment group and a hydroxyl group are, for example, those shown in the following formula.

In the above formulas [A1] to [A5], ^A1 and ^A2 are each independently a hydrogen atom or a methyl group, ^X1 is a divalent group bonded to an alkylene group having 1 to 18 carbon atoms, a phenylene group, a biphenylene group, or a combination thereof, via one or more bonds selected from a single bond, an ether bond, an ester bond, an amide bond, a carbamate bond, an amine bond, or a combination thereof. ^X2 is a hydrogen atom, a halogen atom, a cyano group, an alkyl group having 1 to 18 carbon atoms, a phenyl group, a biphenylene group, or a cyclohexyl group. In this case, the alkyl group having 1 to 18 carbon atoms, a phenyl group, a biphenylene group, and a cyclohexyl group may be bonded to the benzene ring via a covalent bond, an ether bond, an ester bond, an amide bond, or a urea bond. ^X5 represents a hydroxyl group, a carboxyl group, an amino group or an alkoxysilyl group. ^{X represents a single bond, an oxygen atom or a sulfur atom. X6} represents a hydroxyl group, an alkyl group, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, a phenyl group, a phenoxy group or a biphenyloxy group. ^X7 represents a single bond, an alkylene group having 1 to 20 carbon atoms, a divalent group formed by removing two hydrogen atoms from an aromatic ring, or a divalent group formed by removing two hydrogen atoms from an aliphatic ring. Here, the alkylene group having 1 to 20 carbon atoms may be branched or linear.

Furthermore, among the substituents, phenylene, phenylene, biphenylene, biphenylyl, phenoxy and biphenyloxy may be substituted by one or more substituents which are the same or different and are selected from alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, halogen atoms, trifluoromethyl groups and cyano groups.

In the above formula, ^R1 , ^R2 , ^R3 , ^R4 , ^R5 , ^R6 , ^R7 and ^R8 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.

Examples of the alkyl group having 1 to 18 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, 1-methyl-n-butyl, 2-methyl-n-butyl, 3-methyl-n-butyl, 1,1-dimethyl-n-propyl, 1,2-dimethyl-n-propyl, 2,2-dimethyl-n-propyl, 1-ethyl-n-propyl, n-hexyl, 1-methyl-n-pentyl, 2-methyl-n-pentyl, 3-methyl-n-pentyl, 4-methyl-n-pentyl, 1,1-dimethyl-n-butyl, 1,2-dimethyl-n-butyl 1,3-dimethyl-n-butyl, 2,2-dimethyl-n-butyl, 2,3-dimethyl-n-butyl, 3,3-dimethyl-n-butyl, 1-ethyl-n-butyl, 2-ethyl-n-butyl, 1,1,2-trimethyl-n-propyl, 1,2,2-trimethyl-n-propyl, 1-ethyl-1-methyl-n-propyl, 1-ethyl-2-methyl-n-propyl, n-heptyl, 1-methyl-n-hexyl, 2-methyl-n-hexyl, 3-methyl-n-hexyl, 1,1-dimethyl-n-pentyl, 1,2-dimethyl-n-pentyl, 1,3-dimethyl-n-pentyl, 2,2-dimethyl -n-pentyl, 2,3-dimethyl-n-pentyl, 3,3-dimethyl-n-pentyl, 1-ethyl-n-pentyl, 2-ethyl-n-pentyl, 3-ethyl-n-pentyl, 1-methyl-1-ethyl-n-butyl, 1-methyl-2-ethyl-n-butyl, 1-ethyl-2-methyl-n-butyl, 2-methyl-2-ethyl-n-butyl, 2-ethyl-3-methyl-n-butyl, n-octyl, 1-methyl-n-heptyl, 2-methyl-n-heptyl, 3-methyl-n-heptyl, 1,1-dimethyl-n-hexyl, 1,2-dimethyl-n-hexyl, 1,3-dimethyl-n-hexyl, 2,2- dimethyl-n-hexyl, 2,3-dimethyl-n-hexyl, 3,3-dimethyl-n-hexyl, 1-ethyl-n-hexyl, 2-ethyl-n-hexyl, 3-ethyl-n-hexyl, 1-methyl-1-ethyl-n-pentyl, 1-methyl-2-ethyl-n-pentyl, 1-methyl-3-ethyl-n-pentyl, 2-methyl-2-ethyl-n-pentyl, 2-methyl-3-ethyl-n-pentyl, 3-methyl-3-ethyl-n-pentyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, etc. As the above-mentioned alkylene groups having 1 to 18 carbon atoms, there can be cited divalent groups formed by removing one hydrogen atom from the above-mentioned alkyl groups. As the above-mentioned alkyl group having 1 to 4 carbon atoms, there can be mentioned groups having the corresponding number of carbon atoms among the groups listed above. As the above-mentioned alkoxy group having 1 to 10 carbon atoms, alkoxy group having 1 to 4 carbon atoms, and alkylthio group having 1 to 10 carbon atoms, there can be mentioned groups having the corresponding number of carbon atoms among groups obtained by oxylating or thiolation of the above-mentioned alkyl groups. As the above-mentioned alkylene group having 1 to 20 carbon atoms, there can be mentioned divalent groups obtained by removing one hydrogen atom from the above-mentioned alkyl groups and alkyl groups having 1 to 20 carbon atoms such as n-nonadecanyl and n-eicosyl.

Specific examples of the compound having a photoalignment group and a hydroxyl group as component (A) include 4-(8-hydroxyoctyloxy)cinnamic acid methyl ester, 4-(6-hydroxyhexyloxy)cinnamic acid methyl ester, 4-(4-hydroxybutoxy)cinnamic acid methyl ester, 4-(3-hydroxypropoxy)cinnamic acid methyl ester, 4-(2-hydroxyethoxy)cinnamic acid methyl ester, 4-(4-hydroxybutoxy)cinnamic acid methyl ester, 4-(6-hydroxyhexyloxy)cinnamic acid ethyl ester, 4-(4-hydroxybutoxy)cinnamic acid ethyl ester, 4-(3-hydroxypropoxy)cinnamic acid ethyl ester, 4-(2-hydroxyethoxy)cinnamic acid ethyl ester, 4-hydroxymethoxycinnamic acid ethyl ester, 4-hydroxycinnamic acid 4-(6-hydroxyhexyloxy)cinnamic acid phenyl ester, 4-(4-hydroxybutoxy)cinnamic acid phenyl ester, 4-(3-hydroxypropoxy)cinnamic acid phenyl ester, 4-(2-hydroxyethoxy)cinnamic acid phenyl ester, 4-hydroxymethoxycinnamic acid phenyl ester, 4-hydroxycinnamic acid phenyl ester, 4-(8-hydroxyoctyloxy)cinnamic acid phenyl ester, 4-(6-hydroxyhexyloxy)cinnamic acid phenyl ester, 4-(4-hydroxybutoxy)cinnamic acid phenyl ester, 4-(3-hydroxypropoxy)cinnamic acid phenyl ester, 4-(2-hydroxyethoxy)cinnamic acid phenyl ester, 4-hydroxymethoxycinnamic acid phenyl ester, 4-hydroxycinnamic acid phenyl ester, 4-(8-hydroxyoctyloxy)cinnamic acid phenyl ester, 4-(6-hydroxyhexyloxy)cinnamic acid biphenyl ester, 4-(4-hydroxybutoxy)cinnamic acid biphenyl ester, 4-(3-hydroxypropoxy)cinnamic acid biphenyl ester, 4-(2-hydroxyethoxy)cinnamic acid biphenyl ester, 4-hydroxymethoxycinnamic acid biphenyl ester, 4-hydroxycinnamic acid biphenyl ester, 8-hydroxyoctyl cinnamic acid, 6- Hydroxyhexyl ester, 4-hydroxybutyl cinnamate, 3-hydroxypropyl cinnamate, 2-hydroxyethyl cinnamate, hydroxymethyl cinnamate, 4-(8-hydroxyoctyloxy)azobenzene, 4-(6-hydroxyhexyloxy)azobenzene, 4-(4-hydroxybutoxy)azobenzene, 4-(3-hydroxypropoxy)azobenzene, 4-(2-hydroxyethoxy)azobenzene, 4-hydroxymethoxy Azobenzene, 4-hydroxyazobenzene, 4-(8-hydroxyoctyloxy) chalcone, 4-(6-hydroxyhexyloxy) chalcone, 4-(4-hydroxybutoxy) chalcone, 4-(3-hydroxypropoxy) chalcone, 4-(2-hydroxyethoxy) chalcone, 4-hydroxymethoxy chalcone, 4-hydroxy chalcone, 4'-(8-hydroxyoctyloxy) chalcone, 4'-(6- 4'-(4-hydroxybutoxy)chalcone, 4'-(3-hydroxypropoxy)chalcone, 4'-(2-hydroxyethoxy)chalcone, 4'-hydroxymethoxychalcone, 4'-hydroxychalcone, 7-(8-hydroxyoctyloxy)coumarin, 7-(6-hydroxyhexyloxy)coumarin, 7-(4-hydroxybutoxy)coumarin, 7-(3-hydroxypropoxy)chalcone, 4'-(2-hydroxyethoxy)chalcone, 4'-hydroxymethoxychalcone, 4'-hydroxychalcone, 7-(8-hydroxyoctyloxy)coumarin, 7-(6-hydroxyhexyloxy)coumarin, 7-(4-hydroxybutoxy)coumarin, 7-(3- 6-(4-hydroxybutoxy)coumarin, 6-(3-hydroxypropoxy)coumarin, 6-(2-hydroxyethoxy)coumarin, 6-hydroxymethoxycoumarin, 6-hydroxycoumarin.

Specific examples of compounds having a photo-alignment group and a carboxyl group include cinnamic acid, ferulic acid, 4-nitrocinnamic acid, 4-methoxycinnamic acid, 3,4-dimethoxycinnamic acid, coumarin-3-carboxylic acid, 4-(dimethylamino)cinnamic acid, etc. Specific examples of compounds having a photo-alignment group and an amino group include 4-aminocinnamic acid methyl, 4-aminocinnamic acid ethyl, 3-aminocinnamic acid methyl, 3-aminocinnamic acid ethyl, etc. (A) The low molecular weight photo-alignment component of the component can be exemplified as above, but is not limited thereto.

Furthermore, when the low molecular weight photo-alignment component of component (A) is a compound having a photo-alignment group and a hydroxyl group, a compound having two or more photo-alignment groups and/or two or more hydroxyl groups in the molecule can be used as component (A). Specifically, as component (A), a compound having one hydroxyl group and two or more photo-alignment groups in the molecule, or a compound having one photo-alignment group and two or more hydroxyl groups in the molecule, or a compound having two or more photo-alignment groups and hydroxyl groups in the molecule can be used. For example, as an example of a compound having two or more photo-alignment groups and hydroxyl groups in the molecule, a compound shown in the following formula can be exemplified.

By appropriately selecting such a compound, it is possible to control and increase the molecular weight of the low molecular weight photo-alignment component of component (A). As a result, as described below, when the low molecular weight photo-alignment component of component (A) and the polymer of component (B) and the polymer of component (C) undergo a thermal reaction, the sublimation of the low molecular weight photo-alignment component of component (A) can be suppressed. Furthermore, the cured film forming composition of the present invention can be formed as a cured film as an alignment material with high photoreaction efficiency.

The compound as the component (A) in the cured film forming composition of the present invention may be a mixture of a plurality of compounds having a photo-alignment group and one substituent selected from the group consisting of a hydroxyl group, a carboxyl group and an amino group.

<Component (B)> The component (B) contained in the curing film forming composition of the present invention is a polymer obtained by polymerizing a monomer containing at least an N-alkoxymethyl (meth) acrylamide compound. In addition, N-alkoxymethyl (meth) acrylamide means both N-alkoxymethyl acrylamide and N-alkoxymethyl methacrylamide.

Examples of such polymers include polymers obtained by polymerizing an N-alkoxymethyl (meth) acrylamide compound alone or copolymerizing a copolymerizable monomer. Examples of such polymers include poly(N-butoxymethyl acrylamide), poly(N-ethoxymethyl acrylamide), poly(N-methoxymethyl acrylamide), copolymers of N-butoxymethyl acrylamide and styrene, copolymers of N-butoxymethyl acrylamide and methyl methacrylate, copolymers of N-ethoxymethyl acrylamide and benzyl methacrylate, and copolymers of N-butoxymethyl acrylamide, benzyl methacrylate, and 2-hydroxypropyl methacrylate.

The method for obtaining the polymer of component (B) used in the present invention is not particularly limited. For example, it can be obtained by polymerizing the polymer at a temperature of 50 to 110°C in a solvent in which an N-alkoxymethyl (meth) acrylamide compound and a desired copolymerizable monomer and a polymerization initiator coexist. At this time, the solvent used is not particularly limited as long as it can dissolve the N-alkoxymethyl (meth) acrylamide compound, the desired copolymerizable monomer and a polymerization initiator. As a specific example, it is described in the <Solvent> described later. The polymer obtained by the above method is generally in the form of a solution dissolved in a solvent.

Furthermore, the polymer solution obtained by the above method is put into diethyl ether or water in agitation to precipitate, and the precipitate formed is filtered and washed, and then dried at room temperature or heated under normal pressure or reduced pressure to obtain a polymer powder. Through the above operation, the polymerization initiator and unreacted monomers coexisting with the polymer can be removed, and as a result, a purified polymer powder can be obtained. In the case that the purification cannot be fully achieved by one operation, the obtained powder can be dissolved in a solvent again, and the above operation can be repeated.

In the present invention, the polymer of the component (B) may be used in the form of a powder, or in the form of a solution obtained by dissolving a purified powder in a solvent described below.

Furthermore, in the present invention, the polymer of the component (B) may be a mixture of plural polymers.

In the present invention, when the above-mentioned copolymerizable monomer is used in the production of the polymer of component (B), the amount of the copolymerizable monomer used is preferably 1 mol% to 200 mol%, more preferably 10 mol% to 100 mol%, relative to the total molar number of the monomers used in the production of the polymer of component (B).

The weight average molecular weight of the polymer of component (B) is 1,000 to 500,000, preferably 2,000 to 200,000, more preferably 3,000 to 150,000, and 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 sample.

The polymers of the component (B) may be used alone or in combination of two or more.

＜Component (C)＞ Component (C) is a polymer obtained by polymerizing a monomer containing at least an N-hydroxyalkyl (meth) acrylamide compound. In addition, N-hydroxyalkyl (meth) acrylamide means both N-hydroxyalkyl acrylamide and N-hydroxyalkyl methacrylamide.

When the composition of the present invention is formed into a coating and then heat-cured, the N-alkoxymethyl group of the component (B) reacts with the hydroxyl group of the component (C) to form a bond, thereby making the coating strong and stable and achieving solvent resistance.

Examples of the N-hydroxyalkyl (meth) acrylamide compound include N-(2-hydroxyethyl) acrylamide, N-(2-hydroxyethyl) methacrylamide, N-(2-hydroxypropyl) acrylamide, N-(2-hydroxypropyl) methacrylamide, N-(4-hydroxybutyl) acrylamide, N-(4-hydroxybutyl) methacrylamide, N-(2,3-dihydroxypropyl) acrylamide, and N-(2,3-dihydroxypropyl) methacrylamide.

In the present invention, when manufacturing the polymer of component (C), monomers other than the above-mentioned N-hydroxyalkyl (meth) acrylamide compound (hereinafter also referred to as "other monomers") may be copolymerized. In the present invention, when other monomers are used in manufacturing the polymer of component (C), the amount of the other monomers used is preferably 30 mol% to 90 mol%, more preferably 30 mol% to 70 mol%, relative to the total molar number of the monomers used in manufacturing the polymer of component (C).

As other monomers, for example, industrially available monomers capable of undergoing free radical polymerization reaction can be cited.

Specific examples of other monomers include unsaturated carboxylic acids, acrylate compounds, methacrylate compounds, amide group-containing monomers, maleimide compounds, acrylonitrile, maleic anhydride, styrene compounds, and vinyl compounds.

Specific examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid and the like.

Examples of the acrylate compound include methacrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthracenyl acrylate, anthracenyl methacrylate, phenyl acrylate, 2,2,2-trifluoroethyl acrylate, tert-butyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, Acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2,3-dihydroxypropyl acrylate, diethylene glycol monoacrylate, caprolactone 2-(acryloyloxy)ethyl ester, poly(ethylene glycol) ethyl ether acrylate, 5-acryloyloxy-6-hydroxynorbornene-2-carboxylic acid-6-lactone, acrylyl ethyl isocyanate, and 8-ethyl-8-tricyclodecyl acrylate, epoxypropyl acrylate, etc.

Examples of the methacrylate compound include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthracenyl methacrylate, anthracenyl methyl methacrylate, phenyl methacrylate, 2,2,2-trifluoroethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl-2-adamantyl methacrylate, acrylate, γ-butyrolactone methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2,3-dihydroxypropyl methacrylate, diethylene glycol monomethacrylate, caprolactone 2-(methacryloyloxy)ethyl ester, poly(ethylene glycol) ethyl ether methacrylate, 5-methacryloyloxy-6-hydroxynorbornene-2-carboxylic acid-6-lactone, methacryloyl ethyl isocyanate, and 8-ethyl-8-tricyclodecyl methacrylate, epoxypropyl methacrylate, etc.

Examples of the amide group-containing monomer include N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, N-methyl(methyl)acrylamide, N-ethyl(methyl)acrylamide, N-propyl(methyl)acrylamide, N-butyl(methyl)acrylamide, N-isobutyl(methyl)acrylamide, N-hexyl(methyl)acrylamide, N-octyl(methyl)acrylamide, amine, N-(methoxymethyl)(meth)acrylamide, N-(methoxybutyl)(meth)acrylamide, N-(ethoxymethyl)(meth)acrylamide, N-(butoxymethyl)(meth)acrylamide, N-(isobutoxymethyl)(meth)acrylamide, N-(isobutoxyethyl)(meth)acrylamide, N-vinylphthalimide, N-vinylsuccinimide, etc.

Examples of the vinyl compound include vinyl ether, methyl vinyl ether, benzyl vinyl ether, vinyl naphthalene, vinyl anthracene, vinyl biphenyl, vinyl carbazole, 2-hydroxyethyl vinyl ether, phenyl vinyl ether, and propyl vinyl ether.

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

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

Examples of the acrylonitrile compound include acrylonitrile and the like.

The method for obtaining the polymer of the component (C) used in the present invention is not particularly limited. In the method for producing the polymer of the component (B), an N-hydroxyalkyl (meth)acrylamide compound may be used instead of the N-alkoxymethyl (meth)acrylamide compound.

The weight average molecular weight of the polymer of component (C) is 1,000 to 500,000, preferably 2,000 to 200,000, more preferably 3,000 to 150,000, and more preferably 3,000 to 100,000. The weight average molecular weight is a value obtained by gel permeation chromatography (GPC) using polystyrene as a standard sample.

The polymers of the component (C) may be used alone or in combination of two or more.

The content of the polymer of the component (B) and the polymer of the component (C) in the cured film forming composition of the present invention is preferably 100 to 3000 parts by mass, more preferably 200 to 2500 parts by mass, and particularly preferably 300 to 2000 parts by mass, relative to 100 parts by mass of the component (A).

The mass ratio of component (B) to component (C) is preferably 1:99 to 99:1, more preferably 5:95 to 95:5, and particularly preferably 10:90 to 90:10.

<(D) component> The cured film forming composition of the present invention may contain a crosslinking catalyst as a (D) component in addition to the (A) component, the (B) component, and the (C) component. As the crosslinking catalyst of the (D) component, for example, an acid or a thermal acid generator may be used. The (D) component is effective in promoting the thermal curing reaction of the cured film forming composition of the present invention.

As the above-mentioned acid, there can be cited compounds containing sulfonic acid groups, hydrochloric acid or its salts, etc. Moreover, as the above-mentioned thermal acid generator, as long as it is a compound that generates acid by thermal decomposition during pre-baking or post-baking, that is, a compound that generates acid by thermal decomposition at a temperature of 80°C to 250°C, it is not particularly limited. As the acid, for example, hydrochloric acid or its salt; 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, etc., or sulfonic acids or their hydrates or salts, etc. can be cited. Examples of compounds that generate an acid by heat include bis(toluenesulfonyloxy)ethane, bis(toluenesulfonyloxy)propane, bis(toluenesulfonyloxy)butane, p-nitrobenzyl toluenesulfonate, o-nitrobenzyl toluenesulfonate, 1,2,3-phenylenetris(methylsulfonate), p-pyridinium toluenesulfonate, p-morpholinium toluenesulfonate, p-ethyl toluenesulfonate, p-propyl toluenesulfonate, p-butyl toluenesulfonate, p-isobutyl toluenesulfonate, p-methyl toluenesulfonate, p-phenylethyl toluenesulfonate, cyanomethyl p-toluenesulfonate, 2,2,2-trifluoroethyl p-toluenesulfonate, 2-hydroxybutyl p-toluenesulfonate, N-ethyl-p-toluenesulfonamide, and compounds represented by the following formulas.

The content of the component (D) in the cured film forming composition of the present invention is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 6 parts by mass, and more preferably 0.5 to 5 parts by mass, relative to 100 parts by mass of the total of the polymer of the component (B) and the polymer of the component (C). By making the content of the component (D) greater than 0.01 parts by mass, sufficient heat curing and solvent resistance can be imparted, and high sensitivity to light irradiation can also be imparted. However, when the content exceeds 10 parts by mass, the storage stability of the composition may be reduced.

<Component (E)> The cured film forming composition of the present invention may contain a component that improves the adhesion of the formed cured film (hereinafter also referred to as an adhesion-enhancing component) as component (E).

The adhesion-enhancing component of component (E) can link the polymerizable functional group of the polymerizable liquid crystal and the cross-linking reaction site of the alignment material through a covalent bond, thereby improving the adhesion of the alignment material and the polymerizable liquid crystal layer obtained from the cured film-forming composition of the present invention. As a result, the phase difference material of the present embodiment, which is formed by laminating the cured polymerizable liquid crystal on the alignment material of the present embodiment, can maintain strong adhesion even under high temperature and high humidity conditions, and can show high durability against peeling, etc.

As the component (E), a monomer or polymer having a group selected from a hydroxyl group and an N-alkoxymethyl group and a polymerizable group is preferred. Examples of such component (E) include compounds having a hydroxyl group and a (meth)acryloyl group, compounds having an N-alkoxymethyl group and a (meth)acryloyl group, and polymers having an N-alkoxymethyl group and a (meth)acryloyl group. Specific examples thereof are shown below.

As an example of the component (E), there can be cited a polyfunctional acrylate containing a hydroxyl group (hereinafter, also referred to as a polyfunctional acrylate containing a hydroxyl group). As an example of the polyfunctional acrylate containing a hydroxyl group as the component (E), there can be cited, for example, pentaerythritol triacrylate and dipentaerythritol pentaacrylate.

Another example of the component (E) is a compound having one (meth)acryloyl group and one or more hydroxyl groups.

Examples of the compound of the component (E) include compounds having at least one polymerizable group including a C=C double bond and at least one N-alkoxymethyl group in one molecule.

Examples of the polymerizable group containing a C=C double bond include an acryl group, a methacryl group, a vinyl group, an allyl group, and a maleimide group.

As the compound having at least one polymerizable group including a C=C double bond and at least one N-alkoxymethyl group in one molecule, preferably, there can be mentioned a compound represented by the following formula (X1). (In the formula, R ³¹ represents a hydrogen atom or a methyl group, and R ³² represents a hydrogen atom, or a linear or branched alkyl group having 1 to 10 carbon atoms).

Examples of the alkyl group having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, 1-methyl-n-butyl, 2-methyl-n-butyl, 3-methyl-n-butyl, 1,1-dimethyl-n-propyl, 1,2-dimethyl-n-propyl, 2,2-dimethyl-n-propyl, 1-ethyl-n-propyl, n-hexyl, 1-methyl-n-pentyl, 2-methyl-n-pentyl, 3-methyl-n-pentyl, 4-methyl-n-pentyl, 1,1-dimethyl-n-butyl , 1,2-dimethyl-n-butyl, 1,3-dimethyl-n-butyl, 2,2-dimethyl-n-butyl, 2,3-dimethyl-n-butyl, 3,3-dimethyl-n-butyl, 1-ethyl-n-butyl, 2-ethyl-n-butyl, 1,1,2-trimethyl-n-propyl, 1,2,2-trimethyl-n-propyl, 1-ethyl-1-methyl-n-propyl, 1-ethyl-2-methyl-n-propyl, n-heptyl, 1-methyl-n-hexyl, 2-methyl-n-hexyl, 3-methyl-n-hexyl, 1,1-dimethyl-n-pentyl, 1,2-dimethyl-n -pentyl, 1,3-dimethyl-n-pentyl, 2,2-dimethyl-n-pentyl, 2,3-dimethyl-n-pentyl, 3,3-dimethyl-n-pentyl, 1-ethyl-n-pentyl, 2-ethyl-n-pentyl, 3-ethyl-n-pentyl, 1-methyl-1-ethyl-n-butyl, 1-methyl-2-ethyl-n-butyl, 1-ethyl-2-methyl-n-butyl, 2-methyl-2-ethyl-n-butyl, 2-ethyl-3-methyl-n-butyl, n-octyl, 1-methyl-n-heptyl, 2-methyl-n-heptyl, 3-methyl-n-heptyl, 1,1-dimethyl n-pentyl, 1-methyl-2-ethyl-n-pentyl, 1-methyl-3-ethyl-n-pentyl, 2-methyl-2-ethyl-n-pentyl, 2-methyl-3-ethyl-n-pentyl, 3-methyl-3-ethyl-n-pentyl, n-nonyl, n-decyl, etc.

Specific examples of the compound represented by the above formula (X1) include acrylamide compounds or methacrylamide compounds substituted with a hydroxymethyl group or an alkoxymethyl group such as N-hydroxymethyl (meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-ethoxymethyl (meth)acrylamide, and N-butoxymethyl (meth)acrylamide. In addition, (meth)acrylamide refers to both methacrylamide and acrylamide.

As other aspects of the compound having a polymerizable group containing a C=C double bond and an N-alkoxymethyl group as the component (E), preferably, for example, the following compounds can be cited.

The content of the component (E) in the cured film forming composition of the present invention is preferably 1 to 100 parts by mass, more preferably 5 to 70 parts by mass, relative to 100 parts by mass of the low molecular weight photo-alignment component (A).

<Solvent> The curable film forming composition of the present invention is mainly used in a solution state dissolved in a solvent. The solvent used at this time can dissolve the (A) component, the (B) component and the (C) component, and the necessary (D) component, the (E) component and/or other additives described below, and its type and structure are not particularly limited.

Specific examples of the solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl solvent acetate, ethyl solvent acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-butanone, 3-methyl-2-pentanone, 2-pentanone, 2-heptanone, γ-butyrolactone, 2- Ethyl hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutyrate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone. These solvents may be used alone or in combination of two or more.

<Other additives> In addition, as long as the effects of the present invention are not impaired, the curing film forming composition of the present invention may contain sensitizers, silane coupling agents, surfactants, rheology modifiers, pigments, dyes, storage stabilizers, defoamers, antioxidants, etc. as necessary.

For example, the sensitizer is a substance that effectively promotes the photoreaction after forming a heat-cured film using the cured film-forming composition of the present invention.

As an example of other additives, sensitizers include benzophenone, anthracene, anthraquinone, thioxanthene, and derivatives thereof, as well as nitrophenyl compounds. Among them, benzophenone derivatives and nitrophenyl compounds are preferred. As specific examples of preferred compounds, N,N-diethylaminobenzophenone, 2-nitrofluorene, 2-nitrofluorene, 5-nitroacenaphthene, 4-nitrobiphenyl, 4-nitrocinnamic acid, 4-nitrostilbene, 4-nitrobenzophenone, 5-nitroindole, and the like can be cited. In particular, N,N-diethylaminobenzophenone, which is a derivative of benzophenone, is preferred.

The sensitizers are not limited to the above ones. In addition, the sensitizers can be used alone or in combination of two or more compounds.

The usage ratio of the sensitizer in the hardened film forming composition of the present invention is preferably 0.1 to 20 parts by weight, more preferably 0.2 to 10 parts by weight, relative to 100 parts by weight of the low molecular weight photo-alignment component (A). If the ratio is too small, the effect of the sensitizer may not be fully obtained, and if it is too large, the transmittance may be reduced and the coating may be rough.

<Preparation of the curing film forming composition> The curing film forming composition of this embodiment contains: (A) a low molecular weight photo-alignment component, (B) a polymer formed by polymerizing a monomer containing at least an N-alkoxymethyl (meth) acrylamide compound, and (C) a polymer formed by polymerizing a monomer containing at least an N-hydroxyalkyl (meth) acrylamide compound. In addition, (D) a crosslinking catalyst, (E) an adhesion enhancing component and/or other additives may be contained as necessary.

The following details the blending ratio, preparation method, etc. when the cured film forming composition of the present invention is used as a solution. The ratio of the solid components in the cured film forming composition of the present invention is not particularly limited as long as each component is uniformly dissolved in the solvent, and is preferably 1 mass% to 80 mass%, preferably 3 mass% to 60 mass%, and more preferably 5 mass% to 40 mass%. Here, the solid components refer to all the components of the cured film forming composition minus the solvent.

The method for preparing the curable film forming composition of the present invention is not particularly limited. For example, the preparation method includes a method of mixing the (A) component, the (C) component, and the (D) component and the (E) component as required in a predetermined ratio with respect to a solution of the (B) component dissolved in a solvent to prepare a uniform solution, or a method of adding other additives as required in an appropriate stage of the preparation method.

In the preparation of the curable film forming composition of the present invention, the polymer solution obtained by the polymerization reaction in the solvent can be directly used. In this case, for example, the solution of the component (C) is added with the components (A), (B), and if necessary, (D) and (E) to prepare a uniform solution. At this time, additional solvent can be added for the purpose of adjusting the concentration. In this case, the solvent used in the formation process of the component (C) and the solvent used for adjusting the concentration of the curable film forming composition can be the same or different.

Furthermore, the prepared solution of the cured film forming composition is preferably filtered using a filter having a pore size of about 0.2 μm before use.

<Curing film, alignment material and phase difference material> The solution of the curing film forming composition of the present invention is applied to a substrate (e.g., a silicon/silicon dioxide coated substrate, a silicon nitride substrate, a substrate coated with a metal such as aluminum, molybdenum, chromium, etc., a glass substrate, a quartz substrate, an ITO substrate, etc.) or a film (e.g., a triacetyl cellulose (TAC) film, a cycloolefin polymer) A coating film is formed by coating on a resin film such as a polymer film, a polyethylene terephthalate film, an acrylic film, etc. by a rod coating method, a spin coating method, a cast coating method, a roll coating method, a slit coating method, a slit coating method followed by a spin coating method, an ink jet coating method, a printing method, etc., and then, by heating and drying using a heating plate or an oven, a cured film can be formed.

As the conditions for heat drying, the components of the alignment material formed from the cured film will not precipitate to the extent of the polymerizable liquid crystal solution coated thereon, and the crosslinking reaction using the crosslinking agent will proceed. For example, the heating temperature and heating time can be appropriately selected from the range of 60°C to 200°C and the time of 0.4 minutes to 60 minutes. The heating temperature and heating time are preferably 70°C to 160°C and 0.5 minutes to 10 minutes.

The thickness of the cured film formed using the cured film forming composition of the present invention is, for example, 0.05 μm to 5 μm, which can be appropriately selected after considering the step difference or optical and electrical properties of the substrate used.

The cured film formed by this operation can function as an alignment material, that is, a component for aligning a compound having liquid crystal properties such as liquid crystal, by irradiating with polarized UV.

As a method of polarized UV irradiation, ultraviolet light or visible light with a wavelength of 150nm to 450nm is usually used, and linear polarized light is irradiated from a vertical or oblique direction at room temperature or in a heated state.

Since the alignment material formed by the cured film forming composition of the present invention has solvent resistance and heat resistance, after coating the phase difference material including the polymerizable liquid crystal solution on the alignment material, the phase difference material is made into a liquid crystal state by heating to the phase transition temperature of the liquid crystal, and the phase difference material is aligned on the alignment material. Moreover, by directly curing the phase difference material in the alignment state, the phase difference material can be formed as a layer having optical anisotropy.

As the phase difference material, for example, a liquid crystal monomer having a polymerizable group and a composition containing the same can be used. In addition, when the substrate forming the alignment material is a film, the film having the phase difference material of the present invention can be used as a phase difference film. The phase difference material forming such a phase difference material is a liquid crystal material that adopts a horizontal alignment, a cholesterol alignment, a vertical alignment, a mixed alignment, etc. on the alignment material, and can be used separately according to the necessary phase difference.

Furthermore, in the case of manufacturing a patterned phase difference material used in a 3D display, on a cured film formed by the above method and formed from a composition of the cured film of the present invention, a mask of line width and line spacing pattern is placed, and polarized UV is exposed from a specified reference, for example, in a direction of +45 degrees. After removing the mask, polarized UV is exposed in a direction of -45 degrees, and an alignment material is obtained in which two types of liquid crystal alignment regions with different alignment control directions of the liquid crystal are formed. Thereafter, after applying a phase difference material containing a polymerizable liquid crystal solution, the phase difference material is made into a liquid crystal state by heating to the phase transition temperature of the liquid crystal, and the alignment is made on the alignment material. Furthermore, the phase difference material that has become an alignment state is directly cured, and a patterned phase difference material in which two types of phase difference regions with different phase difference characteristics are individually arranged in a plurality of regularities can be obtained.

Furthermore, two substrates with the alignment material of the present invention formed by the above operation can be used, and after being bonded together with a spacer in a manner that the alignment materials on the two substrates face each other, liquid crystal can be injected between the substrates to form a liquid crystal display element with the liquid crystal aligned. Therefore, the cured film forming composition of the present invention can be suitably used in the manufacture of various phase difference materials (phase difference films) or liquid crystal display elements, etc. [Example]

Hereinafter, the present invention will be specifically described by taking the embodiments of the present invention as examples, but the present invention is not to be construed as being limited to the examples.

[Omission symbols used in the examples] The meanings of the omission symbols used in the following examples are as follows. <Raw materials> BMAA: N-butoxymethyl acrylamide AIBN: α,α'-azobisisobutyronitrile MMA: methyl methacrylate HEAA: N-(2-hydroxyethyl)acrylamide MAIB: dimethyl 2,2-azobisisobutyrate

＜Ingredient A＞ MCA: 4-Methoxycinnamic acid

<Component B> PB-1: a component represented by the following structural formula.

<Component C> PC-1: a component having the following structural formula. PC-2: The one represented by the following structural formula.

＜Component D＞ PTSA: p-Toluenesulfonic acid monohydrate

<Component E> E-1: A compound having an N-alkoxymethyl group and an acryl group represented by the following structural formula

<Solvent> The resin compositions of the embodiments and comparative examples contain a solvent, and propylene glycol monomethyl ether (PM) and butyl acetate (BA) are used as the solvent.

<Measurement of molecular weight of polymer> The molecular weight of the acrylic copolymer in the polymerization example was measured by the following operation using a gel permeation chromatography (GPC) apparatus (HLC-8320) manufactured by Tosoh Corporation and columns manufactured by Tosoh Corporation (TSKgel ALPHA4000, TSKgel ALPHA3000). In addition, the number average molecular weight (hereinafter referred to as Mn) and weight average molecular weight (hereinafter referred to as Mw) described below are expressed as polystyrene-equivalent values. Column temperature: 40°C Eluent: tetrahydrofuran Flow rate: 1.0 mL/min Standard sample for calibration curve preparation: Standard polystyrene manufactured by Tosoh Corporation (molecular weight 427,000, 190,000, 37,900, 18,100, 5,970, 2,420, 1,010)

<Synthesis of component B> <Polymerization Example-1> By dissolving 100.0 g of BMAA and 1.0 g of AIBN as a polymerization catalyst in 193.5 g of PM and reacting at 80°C for 20 hours, an acrylic polymer solution was obtained. The Mn of the obtained acrylic polymer was 10,000 and the Mw was 23,000. The acrylic polymer solution was slowly dripped into 2000.0 g of hexane to precipitate a solid, and the polymer (PB-1) was obtained by filtering and drying under reduced pressure.

<Synthesis of component C> <Polymerization example-2> 7.0g of MMA, 5.8g of HEAA, and 0.23g of polymerization catalyst MAIB were dissolved in 13.0g of PM. 6.50g of PM was added to a four-neck flask in advance and the dissolved solution was dripped into a drip tank preheated to 85°C for 3 hours, and an acrylic polymer solution was obtained by reacting it for 3 hours under reflux. The Mn of the obtained acrylic polymer was 12,600 and the Mw was 43,100. A 40% PM solution of the target polymer (PC-1) was obtained.

<Synthesis of component C> <Polymerization example-3> 47.10g of BMAA, 34.5g of HEAA, and 0.829g of polymerization catalyst MAIB were dissolved in 82.50g of PM. 41.25g of PM was added to a four-neck flask in advance and the dissolved solution was dripped into a drip tank preheated to 85°C for 3 hours. After dripping, the acrylic polymer solution was obtained by reacting it for 5 hours. The Mn of the obtained acrylic polymer was 6,500 and the Mw was 17,000. A 40% PM solution of the target polymer (PC-2) was obtained.

<Preparation of liquid crystal alignment agent (cured film forming composition)> <Preparation Example 1> Mix 0.079 g of MCA as component (A), 0.66 g of PB-1 obtained in Polymerization Example-1 as component (B), 0.26 g of 40% PM solution of polymer (PC-1) obtained in Polymerization Example-2 as component (C), 0.056 g of E-1 (94.6% BA solution manufactured by Junsei Chemical Co., Ltd.) as component (E), and 0.021 g of PTSA as component (D), and add 6.65 g of PM and 1.62 g of BA as solvent to the mixture, stir for 1 hour, and visually confirm that the mixture has dissolved to obtain a solution. Next, the obtained solution was filtered using a filter with a pore size of 0.2 μm to prepare a liquid crystal alignment agent (A-1).

<Preparation Examples 2~6> Except for using the types and blending amounts of the components shown in Table 1 below, the other operations are the same as in Preparation Example 1 to prepare the liquid crystal alignment agents (A-2)~(A-4), (B-1), and (B-2).

APEPO-1: RFK-505 (manufactured by Kawasaki Chemical Industries, Ltd.) PEPO-1: Polylite 8651 (manufactured by DIC Corporation)

<Preparation of polymerizable liquid crystal solution for horizontal alignment> <Preparation Example 1> Add 1.57g of LC-242 (produced by BASF) for polymerizable liquid crystal for horizontal alignment, 0.047g of Irgacure907 (produced by BASF) for photoradical initiator, 0.008g of BYK-361N for leveler, and then add 6.55g of N-methylpyrrolidone (NMP) and 9.83g of cyclopentanone as solvent, stir for 2 hours and visually confirm that it has dissolved, to obtain 9% by mass of polymerizable liquid crystal solution LC-1.

<Formation of liquid crystal alignment film and preparation of phase difference film><Example1> On a triacetyl cellulose (TAC) film as a substrate, the liquid crystal alignment agent (A-1) prepared in Preparation Example 1 was applied to a wet film thickness of 6 μm using a rod coater. In a heat cycle oven, heat drying was performed at 130°C for 2 minutes to form a cured film on the film. Next, a linear polarized light of 313 nm was vertically irradiated to the surface of the cured film at an exposure dose of 10 mJ/ ^cm2 to form a liquid crystal alignment film. On the above-mentioned liquid crystal alignment film, a polymerizable liquid crystal solution LC-1 for horizontal alignment was applied to a wet film thickness of 34 μm using a rod coater. Next, after being dried in an oven at 120°C for 2 minutes, the polymerizable liquid crystal was cured by vertically irradiating the film with 365nm non-polarized light at an exposure dose of 300mJ/ ^cm2 under nitrogen to produce a phase difference film.

＜Examples 2 to 4＞ Using (A-2) to (A-4) as liquid crystal alignment agents, the phase difference film was prepared by the same operation as in Example 1.

<Comparative Example 1> On the TAC film used as a substrate, the liquid crystal alignment agent (B-1) prepared in Preparation Example 1 was applied to a wet film thickness of 4μm using a rod coater. In a heat cycle oven, heat drying was performed at 130°C for 2 minutes to form a cured film on the film. Next, the surface of the cured film was vertically irradiated with 313nm linear polarized light at an exposure dose of 10mJ/ ^cm2 to form a liquid crystal alignment film. On the above-mentioned liquid crystal alignment film, a polymerizable liquid crystal solution LC-1 for horizontal alignment was applied to a wet film thickness of 34μm using a rod coater. Next, after heat drying at 120°C for 2 minutes in an oven, the polymerizable liquid crystal was cured by vertically irradiating with 365nm non-polarized light at an exposure dose of 300mJ/ ^cm2 under nitrogen to produce a phase difference film.

<Comparative Example 2> Using (B-1) as a liquid crystal alignment agent, the same operation as in Comparative Example 1 was performed to produce a phase difference film.

The phase difference films prepared above were evaluated according to the following method. The evaluation results are shown in Table 2.

<Evaluation of Orientation> Use a pair of polarizing plates to clamp the retardation film on the prepared substrate, and visually observe the retardation characteristics under the orthogonal Nicol. The ones that exhibit retardation without defects are rated as ○, and those that do not exhibit retardation are rated as ×, and recorded in the "Orientation" column.

<TAC protection> The retardation film containing the TAC film that was produced was rated as ○ if it was not curled, and rated as × if it was curled, and recorded in the "protection" column.

From the results in Table 2, it is clear that by using a polymer obtained by polymerizing a monomer containing an N-hydroxyalkyl (meth) acrylamide compound as component (C), it is possible to obtain an orientation property for a liquid crystal solution containing NMP, and it is also possible to protect the TAC film from damage caused by NMP. [Industrial Applicability]

The cured film forming composition of the present invention is very useful as a liquid crystal alignment film of a liquid crystal display element, or an alignment material for forming an optical anisotropic film disposed inside or outside a liquid crystal display element, and is particularly suitable as a material for forming a patterned phase difference material of a 3D display. In addition, it is suitable as a material for forming a cured film such as a protective film, a planarization film, and an insulating film in various displays such as thin film transistor (TFT) type liquid crystal display elements or organic EL elements, and is particularly suitable as a material for forming an interlayer insulating film of a TFT type liquid crystal element, a protective film of a color filter, or an insulating film of an organic EL element.

Claims (8)

A cured film forming composition characterized by containing: (A) a compound having a photo-alignment group and a substituent selected from the group consisting of a hydroxyl group, a carboxyl group and an amino group, (B) a polymer obtained by polymerizing a monomer containing at least an N-alkoxymethyl (meth) acrylamide compound, and (C) a polymer obtained by polymerizing a monomer containing at least an N-hydroxyalkyl (meth) acrylamide compound; the photo-alignment group of (A) is a cinnamyl group, a chalcone group, a coumarin group, or a group having an azobenzene structure. The hardened film forming composition of claim 1 further contains a crosslinking catalyst as component (D). The hardened film forming composition of claim 1 or 2 further contains an adhesion enhancing component as component (E). For the hardened film forming composition of claim 1 or 2, the total amount of component (B) and component (C) is 100 to 3000 parts by mass relative to 100 parts by mass of component (A). For example, in the hardened film forming composition of claim 1 or 2, the mass ratio of component (B) to component (C) is 1:99 to 99:1. The hardened film forming composition of claim 2 contains 0.01 to 10 parts by mass of component (D) relative to 100 parts by mass of the total of component (B) and component (C). An alignment material characterized by being obtained by using a hardened film forming composition as described in any one of claim 1 to claim 6. A phase difference material characterized by being formed using a cured film obtained from a cured film forming composition as described in any one of claims 1 to 6.