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

Abstract

[Problem] To provide a cured film-forming composition which exhibits improved storage stability and gives an alignment material that exhibits excellent alignment sensitivity, excellent alignment properties and excellent adhesion to a TAC film. [Solution] A cured film-forming composition that contains: (A) a compound having a photo-aligning group and a substituent group selected from among a hydroxy group, a carboxyl group and an amino group; (B) a hydrophilic polymer having one or more substituent groups selected from among a hydroxy group, a carboxyl group and an amino group; (C) a polymer obtained by polymerizing a monomer such as an N-hydroxymethyl compound or an N-alkoxymethyl(meth)acrylamide compound; (D) a crosslinking catalyst; and a solvent that contains both an alcohol having a 1-5 carbon atoms and a C1-4 alkyl ester of a C1-4 fatty acid. Using this cured film-forming composition, a cured film is formed, and an alignment material is formed using optical alignment technology. A polymerizable liquid crystal is coated on the alignment material, curing is performed, and a phase difference material is obtained.

Description

Technical Field

[0001] The present invention relates to a cured film forming composition, an alignment material, and a retardation material.

Background Art

[0002] In the case of a circularly polarized glasses type 3D display, a retardation material is usually disposed on a display element that forms an image such as a liquid crystal panel. This retardation material is composed of a plurality of two types of retardation regions having different retardation characteristics regularly arranged, and constitutes a patterned retardation material. Hereinafter, in this specification, a retardation material patterned so as to arrange a plurality of retardation regions having different retardation characteristics as described above is referred to as a patterned retardation material.

[0003] The patterned retardation material can be produced, for example, by optically patterning a retardation material made of a polymerizable liquid crystal as disclosed in Patent Document 1. The optical patterning of the retardation material made of a polymerizable liquid crystal utilizes an optical alignment technique known in the formation of an alignment material for a liquid crystal panel. That is, a coating film made of an optically alignable material is provided on a substrate, and the coating film is irradiated with two types of polarized light having different polarization directions. Then, an optical alignment film is obtained as an alignment material in which two types of liquid crystal alignment regions having different liquid crystal alignment control directions are formed. A solution-like retardation material containing a polymerizable liquid crystal is applied on this optical alignment film to realize the alignment of the polymerizable liquid crystal. Thereafter, the aligned polymerizable liquid crystal is cured to form a patterned retardation material.

[0004] The antireflection film of an organic EL display is composed of a linear polarizing plate and a quarter-wave retardation plate, converts external light traveling toward the panel surface of the image display panel into linearly polarized light by the linear polarizing plate, and then converts it into circularly polarized light by the subsequent quarter-wave retardation plate. Here, although the external light by this circularly polarized light is reflected on the surface of the image display panel or the like, the rotation direction of the polarization plane is reversed during this reflection. As a result, this reflected light is converted into linearly polarized light in a direction blocked by the linear polarizing plate from the quarter-wave retardation plate, contrary to the arrival time, and then blocked by the subsequent linear polarizing plate, and as a result, the emission to the outside is significantly suppressed.

[0005] Regarding this quarter-wave retardation plate, Patent Document 2 has proposed a method of forming this optical film with inverse dispersion characteristics by combining a half-wave plate and a quarter-wave plate to form a quarter-wave retardation plate. In the case of this method, in a wide wavelength band used for displaying a color image, an optical film can be formed with inverse dispersion characteristics by using a liquid crystal material with positive dispersion characteristics.

[0006] In recent years, as a liquid crystal material applicable to this retardation layer, those having inverse dispersion characteristics have been proposed (Patent Documents 3 and 4). According to such a liquid crystal material with inverse dispersion characteristics, instead of forming a quarter-wave retardation plate with two retardation layers by combining a half-wave plate and a quarter-wave plate, a retardation layer can be formed with a single layer to ensure inverse dispersion characteristics, and thereby an optical film capable of ensuring a desired retardation in a wide wavelength band can be realized with a simple configuration.

[0007] An alignment layer is used to align the liquid crystal. As a method for forming the alignment layer, for example, a rubbing method and a photo-alignment method are known. The photo-alignment method is useful in that it does not generate static electricity or dust, which are problems of the rubbing method, and can control quantitative alignment processing.

[0008] In the formation of an alignment material using the photo-alignment method, as available photo-alignment materials, acrylic resins, polyimide resins, etc. having photo-dimerizable sites such as cinnamoyl groups and chalcone groups in the side chain are known. It has been reported that these resins exhibit the performance of controlling the alignment of liquid crystals (hereinafter, also referred to as liquid crystal alignment property) by irradiating with polarized UV light (see Patent Documents 5 to 7).

[0009] In addition, in a photo-alignment agent using a cinnamoyl moiety, there is also an example in which a thermal crosslinking system is introduced to improve alignment sensitivity and impart solvent resistance (see Patent Documents 8 and 9).

Prior Art Documents

Patent Documents

[0010] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2005-49865 Patent Document 2 Japanese Unexamined Patent Application Publication No. 10-68816 Patent Document 3 U.S. Patent No. 8,119,026 Specification Patent Document 4 Japanese Unexamined Patent Application Publication No. 2009-179563 Patent Document 5 Japanese Patent No. 3,611,342 Publication Patent Document 6 Japanese Unexamined Patent Application Publication No. 2009-058584 Patent Document 7 Japanese Patent Application Laid-Open No. 2001-517719 Patent Document 8 International Patent Application Publication WO2011 / 126022 Patent Document 9 International Patent Application Publication WO2014 / 010688 Summary of the Invention Problems to be Solved by the Invention

[0011] On the other hand, when introducing a thermosetting system into a cured film, if the cured film-forming composition can be stably stored, especially in a state where a crosslinking agent and a crosslinking catalyst coexist, it is highly advantageous in terms of handleability. Therefore, a simple method for improving this storage stability is required. Here, Patent Document 8 and the like describe that when using a TAC substrate, an alcohol solvent is preferable, and the reason is described as that the TAC film exhibits resistance. On the other hand, those patent documents do not describe adding an alcohol solvent to stabilize the varnish, and also do not describe mixing a fatty acid ester solvent that dissolves TAC together with the alcohol solvent to ensure the adhesion between the TAC film and the alignment material.

[0012] The present invention has been made based on the above findings and examination results. That is, the object thereof is to provide an aligning material having excellent alignment sensitivity, excellent orientation, and excellent adhesion to a TAC film, and to provide a curable film-forming composition with improved storage stability.

[0013] Other objects and advantages of the present invention will become apparent from the following description.

Means for Solving the Problems

[0014] The first aspect of the present invention is (A) a compound having a photo-aligning group and any one substituent selected from a hydroxy group, a carboxyl group, and an amino group, (B) a hydrophilic polymer having one or more substituents selected from a hydroxy group, a carboxyl group, and an amino group, (C) a polymer obtained by polymerizing a monomer containing an N-hydroxymethyl compound or an N-alkoxymethyl (meth)acrylamide compound, (D) a crosslinking catalyst, and It relates to a curable film-forming composition characterized by containing a solvent containing both an alcohol having 1 to 5 carbon atoms and a C1-C4 alkyl ester of a fatty acid having 1 to 4 carbon atoms.

[0015] In the first aspect of the present invention, it is preferable that the photo-aligning group of the component (A) is a functional group having a structure that undergoes photodimerization or photoisomerization.

[0016] In the first aspect of the present invention, it is preferable that the photo-aligning group of the component (A) is a cinnamoyl group.

[0017] In the first aspect of the present invention, it is preferable that the photo-aligning group of the component (A) is a group having an azobenzene structure.

[0018] In the first aspect of the present invention, the component (B) is preferably at least one polymer selected from the group consisting of polyether polyol, polyester polyol, polycarbonate polyol, and polycaprolactone polyol.

[0019] In the first aspect of the present invention, the component (B) is preferably cellulose or a derivative thereof.

[0020] In the first aspect of the present invention, the component (B) is preferably an acrylic polymer having at least one of a polyethylene glycol ester group and a hydroxyalkyl ester group having 2 to 5 carbon atoms, and at least one of a carboxyl group and a phenolic hydroxy group.

[0021] In the first aspect of the present invention, the component (B) is preferably an acrylic copolymer obtained by a polymerization reaction of a monomer containing at least one of a monomer having a polyethylene glycol ester group and a monomer having a hydroxyalkyl ester group having 2 to 5 carbon atoms, and at least one of a monomer having a carboxyl group and a monomer having a phenolic hydroxy group. Also, in the first aspect of the present invention, the component (B) is preferably an acrylic polymer having a hydroxyalkyl group in the side chain.

[0022] Also, in the first aspect of the present invention, it is preferable to further contain an adhesion improving component as the component (E).

[0023] In the first aspect of the present invention, the ratio of the component (A) to the component (B) is preferably 5:95 to 60:40 by mass ratio.

[0024] In the first aspect of the present invention, based on 100 parts by mass of the total amount of the compound of the component (A) and the polymer of the component (B), it is preferable to contain 10 to 150 parts by mass of the component (C).

[0025] In the first aspect of the present invention, it is preferable to contain 0.01 part by mass to 10 parts by mass of component (D) with respect to 100 parts by mass of the total amount of the compound of component (A) and the polymer of component (B).

[0026] The second aspect of the present invention relates to an alignment material characterized by being obtained by using the cured film-forming composition of the first aspect of the present invention.

[0027] The third aspect of the present invention relates to a retardation material characterized by being formed using the cured film obtained from the cured film-forming composition of the first aspect of the present invention.

Advantages of the Invention

[0028] According to the first aspect of the present invention, it is possible to provide an alignment material having excellent alignment sensitivity, excellent orientation, and excellent adhesion to a TAC film, and also to provide a cured film-forming composition with improved storage stability.

[0029] According to the second aspect of the present invention, it is possible to provide an alignment material having excellent alignment sensitivity, pattern formability, and transparency, and also excellent alignment uniformity.

[0030] According to the third aspect of the present invention, it is possible to provide a retardation material that can be formed with high efficiency even on alkali glass and enables optical patterning.

Modes for Carrying Out the Invention

[0031] <Cured Film-Forming Composition> The curable film-forming composition of the present embodiment contains a low-molecular-weight photo-orienting component as component (A), a hydrophilic polymer as component (B), a polymer obtained by polymerizing a monomer containing an N-hydroxymethyl compound or an N-alkoxymethyl (meth)acrylamide compound as component (C), and a crosslinking catalyst as component (D). The curable film-forming composition of the present embodiment can further contain a component for improving the adhesiveness of the cured film as component (E) in addition to components (A), (B), (C), and (D). And, as long as the effects of the present invention are not impaired, other additives can be contained.

[0032] Hereinafter, the details of each component will be described. <Component (A)> Component (A) contained in the curable film-forming composition of the present embodiment is the above-described low-molecular-weight photo-orienting component.

[0033] And, the low-molecular-weight photo-orienting component as component (A) can be a compound having a photo-orienting group and any one substituent selected from a hydroxy group, a carboxyl group, and an amino group. In a compound having a photo-orienting group and any one substituent selected from a hydroxy group, a carboxyl group, and an amino group, as described above, the photoreactive group constitutes the hydrophobic photoreactive part in the photoreactive component, and the hydroxy group or the like constitutes the hydrophilic thermal reactive part. In the present invention, the photo-orienting group refers to a functional group of a structural part that undergoes photodimerization or photoisomerization.

[0034] The structural part that undergoes photodimerization is a part that forms a dimer by light irradiation, and specific examples thereof include a cinnamoyl group, a chalcone group, a coumarin group, and an anthracene group. Among these, a cinnamoyl group having high transparency and photodimerization reactivity in the visible light region is preferable. The structural part that undergoes photoisomerization refers to a structural part that changes between a cis form and a trans form by light irradiation, and specific examples thereof include a part composed of an azobenzene structure, a stilbene structure, and the like. Among these, an azobenzene structure is preferable because of its high reactivity. A compound having a photo-orienting group and a hydroxy group is represented by, for example, the following formula.

[0035]

Chem.

[0036] In the above formula, A 1 and A 2 each independently represent a hydrogen atom or a methyl group, and X 1 represents a structure formed by bonding one to three units selected from alkylene having 1 to 18 carbon atoms, phenylene, biphenylene, or a combination thereof through one or more bonds selected from a single bond, an ether bond, an ester bond, an amide bond, a urethane bond, an amino bond, or a combination thereof. X 2 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. In that case, the alkyl group having 1 to 18 carbon atoms, the phenyl group, the biphenyl group, and the cyclohexyl group may be bonded through a covalent bond, an ether bond, an ester bond, an amide bond, or a urea bond. X 5 represents a hydroxy group, a carboxyl group, an amino group, or an alkoxysilyl group. X represents a single bond, an oxygen atom, or a sulfur atom. X 6 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, or a phenyl group. X 7 each independently represents a single bond, an alkylene group having 1 to 20 carbon atoms, an aromatic ring group, or an aliphatic ring group. Here, the alkylene group having 1 to 20 carbon atoms may be branched or linear.

[0037] In addition, in these substituents, phenylene, phenyl group, biphenylene, and biphenyl group may be substituted by the same or different one or more 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.

[0038] In the above formula, R 1 , R 2 , R3 , R 4 , R 5 , R 6 , R 7 and R 8 each independently represents 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.

[0039] Specific examples of the compound having a photo-orienting group and a hydroxy group as the component (A) include, for example, methyl 4-(8-hydroxyoctyloxy)benzoate, methyl 4-(6-hydroxyhexyloxy)benzoate, methyl 4-(4-hydroxybutyloxy)benzoate, methyl 4-(3-hydroxypropyloxy)benzoate, methyl 4-(2-hydroxyethyloxy)benzoate, methyl 4-hydroxymethyloxybenzoate, methyl 4-hydroxybenzoate, ethyl 4-(8-hydroxyoctyloxy)benzoate, ethyl 4-(6-hydroxyhexyloxy)benzoate, ethyl 4-(4-hydroxybutyloxy)benzoate, ethyl 4-(3-hydroxypropyloxy)benzoate, ethyl 4-(2-hydroxyethyloxy)benzoate, ethyl 4-hydroxymethyloxybenzoate, ethyl 4-hydroxybenzoate, phenyl 4-(8-hydroxyoctyloxy)benzoate, phenyl 4-(6-hydroxyhexyloxy)benzoate, phenyl 4-(4-hydroxybutyloxy)benzoate, phenyl 4-(3-hydroxypropyloxy)benzoate, phenyl 4-(2-hydroxyethyloxy)benzoate, phenyl 4-hydroxymethyloxybenzoate, phenyl 4-hydroxybenzoate, biphenyl 4-(8-hydroxyoctyloxy)benzoate, biphenyl 4-(6-hydroxyhexyloxy)benzoate, biphenyl 4-(4-hydroxybutyloxy)benzoate, biphenyl 4-(3-hydroxypropyloxy)benzoate, biphenyl 4-(2-hydroxyethyloxy)benzoate, biphenyl 4-hydroxymethyloxybenzoate, biphenyl 4-hydroxybenzoate, 8-hydroxyoctyl benzoate, 6-hydroxyhexyl benzoate, 4-hydroxybutyl benzoate, 3-hydroxypropyl benzoate, 2-hydroxyethyl benzoate, hydroxymethyl benzoate, 4-(8-hydroxyoctyloxy)azobenzene, 4-(6-hydroxyhexyloxy)azobenzene,4-(4-Hydroxybutyloxy)azobenzene, 4-(3-Hydroxypropyloxy)azobenzene, 4-(2-Hydroxyethyloxy)azobenzene, 4-Hydroxymethyloxyazobenzene, 4-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-Hydroxyoctyloxycoumarin, 6-Hydroxyhexyloxycoumarin, 6-(4-Hydroxybutyloxy)coumarin, 6-(3-Hydroxypropyloxy)coumarin, 6-(2-Hydroxyethyloxy)coumarin, 6-Hydroxymethyloxycoumarin, 6-Hydroxycoumarin are mentioned.

[0040] Specific examples of the compound having a photo-aligning 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-(N,N-dimethylamino)cinnamic acid and the like. Specific examples of the compound having a photo-aligning group and an amino group include methyl-4-aminocinnamic acid, ethyl-4-aminocinnamic acid, methyl-3-aminocinnamic acid, ethyl-3-aminocinnamic acid and the like. (A) component, the low-molecular-weight photo-alignment component, can include the above specific examples, but is not limited thereto.

[0041] Further, when the photo-alignment component as the (A) component is a compound having a photo-alignment group and a hydroxy group, as the (A) component, it is possible to use a compound having two or more photo-alignment groups and / or two or more hydroxy groups in the molecule. Specifically, as the (A) component, a compound having two or more photo-alignment groups together with one hydroxy group in the molecule, a compound having two or more hydroxy groups together with one photo-alignment group in the molecule, or a compound having two or more photo-alignment groups and two or more hydroxy groups in the molecule can be used. For example, for a compound having two or more photo-alignment groups and two or more hydroxy groups in the molecule, as an example, a compound represented by the following formula can be shown.

[0042]

Chemical formula

[0043] By appropriately selecting such a compound, it is possible to control the increase in the molecular weight of the photo-alignment component as the (A) component. As a result, as described later, when the photo-alignment component as the (A) component, the polymer as the (B) component, and the crosslinking agent as the (C) component undergo a thermal reaction, sublimation of the photo-alignment component as the (A) component can be suppressed. And the curable film-forming composition of the present embodiment can form an alignment material with high photoreaction efficiency as a cured film.

[0044] Further, as the compound of the (A) component in the curable film-forming composition of the present embodiment, it may be a mixture of a plurality of compounds having a photo-alignment group and any one substituent selected from a hydroxy group, a carboxyl group, and an amino group.

[0045] <(B) component> The (B) component contained in the curable film-forming composition of the present embodiment is a hydrophilic polymer. And the polymer as component (B) can be a polymer having one or more substituents selected from a hydroxy group, a carboxyl group, and an amino group (hereinafter also referred to as a specific polymer).

[0046] In the cured film-forming composition of the present embodiment, as the specific polymer which is component (B), it is preferable to select a highly hydrophilic polymer having high hydrophilicity so as to be more hydrophilic than component (A). And the specific polymer is preferably a polymer having a hydrophilic group such as a hydroxy group, a carboxyl group, or an amino group, and specifically, it is preferably a polymer having one or more substituents selected from a hydroxy group, a carboxyl group, and an amino group.

[0047] Examples of the polymer as component (B) include polymers having a linear structure or a branched structure such as acrylic polymers, polyamic acids, polyimides, polyvinyl alcohols, polyesters, polyester polycarboxylic acids, polyether polyols, polyester polyols, polycarbonate polyols, polycaprolactone polyols, polyalkyleneimines, polyallylamines, celluloses (cellulose or its derivatives), phenol novolak resins, melamine formaldehyde resins, and cyclic polymers such as cyclodextrins. Among these, as the acrylic polymer, a polymer obtained by polymerizing a monomer having an unsaturated double bond such as an acrylate ester, a methacrylate ester, or styrene can be applied.

[0048] As the specific polymer which is the component (B), preferably, hydroxyalkyl cyclodextrins, celluloses, acrylic polymers having at least one of a polyethylene glycol ester group and a hydroxyalkyl ester group having 2 to 5 carbon atoms and at least one of a carboxyl group and a phenolic hydroxy group, acrylic polymers having an aminoalkyl group in the side chain, acrylic polymers having a hydroxyalkyl group such as polyhydroxyethyl methacrylate in the side chain, polyether polyols, polyester polyols, polycarbonate polyols and polycaprolactone polyols.

[0049] As a preferable example of the specific polymer of the component (B), an acrylic polymer having at least one of a polyethylene glycol ester group and a hydroxyalkyl ester group having 2 to 5 carbon atoms and at least one of a carboxyl group and a phenolic hydroxy group may be any acrylic polymer having such a structure, and is not particularly limited with respect to the skeleton of the main chain of the polymer constituting the acrylic polymer and the types of side chains.

[0050] As a structural unit having at least one of a polyethylene glycol ester group and a hydroxyalkyl ester group having 2 to 5 carbon atoms, a preferable structural unit is represented by the following formula [B1]. As a structural unit having at least one of a carboxyl group and a phenolic hydroxy group, a preferable structural unit is represented by the following formula [B2].

[0051] [Chemical formula]

[0052] In the above formula [B1] and formula [B2], X 3 and X 4 each independently represent a hydrogen atom or a methyl group, and Y 1 is H-(OCH2CH2) n-group (wherein the value of n is from 2 to 50, preferably from 2 to 10), or a hydroxyalkyl group having 2 to 5 carbon atoms, and Y 2 represents a carboxyl group or a phenolic hydroxy group.

[0053] The acrylic polymer as an example of component (B) 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 excessively large exceeding 200,000, the solubility in the solvent may decrease and the handleability may deteriorate. If the weight average molecular weight is excessively small less than 3,000, insufficient curing may occur during thermosetting and the solvent resistance and heat resistance may decrease. The weight average molecular weight is a value obtained by gel permeation chromatography (GPC) using polystyrene as a standard material. The same shall apply hereinafter in this specification.

[0054] As a method for synthesizing the acrylic polymer which is an example of component (B), a method of copolymerizing a monomer having at least one of a polyethylene glycol ester group and a hydroxyalkyl ester group having 2 to 5 carbon atoms (hereinafter also referred to as b1 monomer) and a monomer having at least one of a carboxyl group and a phenolic hydroxy group (hereinafter also referred to as b2 monomer) is convenient.

[0055] Examples of the monomer having the above-described polyethylene glycol ester group include monoacrylate or monomethacrylate of H-(OCH2CH2) n -OH. The value of n is from 2 to 50, preferably from 2 to 10.

[0056] Examples of the monomer having a hydroxyalkyl ester group with 2 to 5 carbon atoms include 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, and 4-hydroxybutyl methacrylate.

[0057] Examples of the monomer having a carboxyl group described above include acrylic acid, methacrylic acid, and vinylbenzoic acid. Examples of the monomer having a phenolic hydroxy group described above include p-hydroxystyrene, m-hydroxystyrene, and o-hydroxystyrene.

[0058] In the present embodiment, when synthesizing the acrylic polymer which is an example of the component (B), monomers other than the b1 monomer and the b2 monomer, specifically, monomers having neither a hydroxy group nor a carboxyl group can be used in combination as long as the effects of the present invention are not impaired.

[0059] Examples of such monomers include acrylic ester compounds such as methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl methacrylate, butyl acrylate, isobutyl acrylate, and t-butyl acrylate; methacrylic ester compounds such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, and t-butyl methacrylate; maleimide compounds such as maleimide, N-methyl maleimide, N-phenyl maleimide, and N-cyclohexyl maleimide; acrylamide compounds, acrylonitrile, maleic anhydride, styrene compounds, and vinyl compounds.

[0060] The usage amounts of the b1 monomer and the b2 monomer used to obtain the acrylic polymer which is an example of the (B) component are preferably such that the b1 monomer is 2 mol% to 95 mol% and the b2 monomer is 5 mol% to 98 mol% based on the total amount of all the monomers used to obtain the acrylic polymer which is the (B) component.

[0061] When using a monomer having only a carboxyl group as the b2 monomer, based on the total amount of all the monomers used to obtain the acrylic polymer which is the (B) component, it is preferable that the b1 monomer is 60 mol% to 95 mol% and the b2 monomer is 5 mol% to 40 mol%. On the other hand, when using a monomer having only a phenolic hydroxyl group as the b2 monomer, it is preferable that the b1 monomer is 2 mol% to 80 mol% and the b2 monomer is 20 mol% to 98 mol%. When the amount of the b2 monomer is too small, the liquid crystal alignment property tends to be insufficient, and when it is too large, the compatibility with the (A) component tends to decrease.

[0062] The method for obtaining the acrylic polymer which is an example of the (B) component is not particularly limited. For example, it can be obtained by a polymerization reaction at a temperature of 50°C to 110°C in a solvent in which the b1 monomer, the b2 monomer, and optionally monomers other than the b1 monomer and the b2 monomer and a polymerization initiator etc. coexist. At that time, the solvent used is not particularly limited as long as it can dissolve the b1 monomer, the b2 monomer, optionally monomers other than the b1 monomer and the b2 monomer used, and the polymerization initiator etc. Specific examples are described in the section of <solvent> described later.

[0063] A preferred example of the specific polymer of component (B), an acrylic polymer having an aminoalkyl group in the side chain, is, for example, one obtained by polymerizing aminoalkyl ester monomers such as aminoethyl acrylate, aminoethyl methacrylate, aminopropyl acrylate, and aminopropyl methacrylate, or a copolymer of the aminoalkyl ester monomer and one or more monomers selected from the group consisting of the above b1 monomer, the above b2 monomer, and monomers other than these monomers, for example, monomers having neither a hydroxy group nor a carboxy group.

[0064] Examples of the acrylic polymer as the preferred specific polymer of component (B), which has a hydroxyalkyl group in the side chain, include, for example, those obtained by polymerizing hydroxyalkyl ester monomers such as hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, hydroxypentyl acrylate, and hydroxypentyl methacrylate, or a copolymer of the hydroxyalkyl ester monomer and one or more monomers selected from the group consisting of the above b1 monomer, the above b2 monomer, and monomers other than these monomers, for example, monomers having neither a hydroxy group nor a carboxy group.

[0065] The acrylic polymer, which is an example of component (B) obtained by the above method, is usually in a state of a solution dissolved in a solvent.

[0066] Also, the solution of the acrylic polymer, which is an example of the component (B) obtained by the above method, is poured into diethyl ether, water, etc. under stirring for reprecipitation. After the generated precipitate is filtered and washed, it is dried at normal temperature or under reduced pressure by heating or at normal pressure to obtain a powder of the acrylic polymer, which is an example of the component (B). By the above operation, the polymerization initiator and unreacted monomers coexisting with the acrylic polymer, which is an example of the component (B), can be removed. As a result, a purified powder of the acrylic polymer, which is an example of the component (B), can be obtained. If it cannot be sufficiently purified in one operation, the obtained powder can be redissolved in a solvent and the above operation can be repeated.

[0067] Examples of the polyether polyol, which is a preferred example of the specific polymer of the component (B), include polyethylene glycol, polypropylene glycol, and propylene glycol. Also, those obtained by adding or condensing propylene oxide, polyethylene glycol, polypropylene glycol, etc. to polyhydric alcohols such as bisphenol A, triethylene glycol, and sorbitol can be mentioned. Specific examples of the polyether polyol include ADEKA's Adeka Polyether P series, G series, EDP series, BPX series, FC series, CM series, NOF's Unionox (registered trademark) HC-40, HC-60, ST-30E, ST-40E, G-450, G-750, Unionox (registered trademark) TG-330, TG-1000, TG-3000, TG-4000, HS-1600D, DA-400, DA-700, DB-400, Nonion (registered trademark) LT-221, ST-221, OT-221, etc.

[0068] As a preferred example of the specific polymer of component (B), polyester polyol includes those obtained by reacting diols such as ethylene glycol, propylene glycol, butylene glycol, polyethylene glycol, and polypropylene glycol with polyvalent carboxylic acids such as adipic acid, sebacic acid, and isophthalic acid. Specific examples of polyester polyol include PolyLite (registered trademark) OD-X-286, OD-X-102, OD-X-355, OD-X-2330, OD-X-240, OD-X-668, OD-X-2108, OD-X-2376, OD-X-2044, OD-X-688, OD-X-2068, OD-X-2547, OD-X-2420, OD-X-2523, OD-X-2555, OD-X-2560 manufactured by DIC; Polyol P-510, P-1010, P-2010, P-3010, P-4010, P-5010, P-6010, F-510, F-1010, F-2010, F-3010, P-1011, P-2011, P-2013, P-2030, N-2010, PNNA-2016 manufactured by Kuraray, etc.

[0069] As a preferred example of the specific polymer of component (B), polycaprolactone polyol includes those obtained by ring-opening polymerization of ε-caprolactam using polyhydric alcohols such as trimethylolpropane and ethylene glycol as initiators. Specific examples of polycaprolactone polyol include PolyLite (registered trademark) OD-X-2155, OD-X-640, OD-X-2568 manufactured by DIC; Placcel (registered trademark) 205, L205AL, 205U, 208, 210, 212, L212AL, 220, 230, 240, 303, 305, 308, 312, 320 manufactured by Daicel Chemical Industries, etc.

[0070] As a polycarbonate polyol which is a preferred example of the specific polymer of component (B), those obtained by reacting a polyhydric alcohol such as trimethylolpropane or ethylene glycol with diethyl carbonate, diphenyl carbonate, ethylene carbonate, etc. can be mentioned. Specific examples of the polycarbonate polyol include Placcel (registered trademark) CD205, CD205PL, CD210, CD220, C-590, C-1050, C-2050, C-2090, C-3090, etc. manufactured by Daicel Chemical Industries, Ltd.

[0071] As cellulose which is a preferred example of the specific polymer of component (B), hydroxyalkyl celluloses such as hydroxyethyl cellulose and hydroxypropyl cellulose, hydroxyalkylalkyl celluloses such as hydroxyethylmethyl cellulose, hydroxypropylmethyl cellulose, and hydroxyethylethyl cellulose, and cellulose, etc. can be mentioned. For example, hydroxyalkyl celluloses such as hydroxyethyl cellulose and hydroxypropyl cellulose are preferred.

[0072] As preferable examples of the specific polymer of component (B), cyclodextrins include cyclodextrins such as α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin, methylated cyclodextrins such as methyl-α-cyclodextrin, methyl-β-cyclodextrin, and methyl-γ-cyclodextrin, hydroxymethyl-α-cyclodextrin, hydroxymethyl-β-cyclodextrin, hydroxymethyl-γ-cyclodextrin, 2-hydroxyethyl-α-cyclodextrin, 2-hydroxyethyl-β-cyclodextrin, 2-hydroxyethyl-γ-cyclodextrin, 2-hydroxypropyl-α-cyclodextrin, 2-hydroxypropyl-β-cyclodextrin, 2-hydroxypropyl-γ-cyclodextrin, 3-hydroxypropyl-α-cyclodextrin, 3-hydroxypropyl-β-cyclodextrin, 3-hydroxypropyl-γ-cyclodextrin, 2,3-dihydroxypropyl-α-cyclodextrin, 2,3-dihydroxypropyl-β-cyclodextrin, 2,3-dihydroxypropyl-γ-cyclodextrin, and other hydroxyalkyl cyclodextrins.

[0073] The melamine formaldehyde resin, which is a preferable example of the specific polymer of component (B), is a resin obtained by polycondensing melamine and formaldehyde and is represented by the following formula.

Chemical formula

[0074] From the viewpoint of storage stability, it is preferable that the methylol group generated during the polycondensation of melamine and formaldehyde in the melamine formaldehyde resin of component (B) is alkylated.

[0075] (B) component of the melamine formaldehyde resin can be obtained by a method which is not particularly limited, but generally, melamine and formaldehyde are mixed, made weakly alkaline using sodium carbonate, ammonia, etc., and then synthesized by heating at 60-100 °C. Further, the methylol group can be alkoxylated by reacting with alcohol.

[0076] (B) component of the melamine formaldehyde resin preferably has a weight average molecular weight of 250 to 5,000, more preferably 300 to 4,000, and even more preferably 350 to 3,500. If the weight average molecular weight is excessively large exceeding 5,000, the solubility in the solvent may decrease and the handleability may deteriorate. If the weight average molecular weight is excessively small less than 250, insufficient curing may occur during thermosetting and the solvent resistance and heat resistance may decrease.

[0077] In the present invention, the (B) component of the melamine formaldehyde resin may be used in liquid form or in solution form in which a purified liquid is redissolved in a solvent described later.

[0078] Also, in the present invention, the (B) component of the melamine formaldehyde resin may be a mixture of a plurality of types of (B) component of the melamine formaldehyde resin.

[0079] As an example of a preferred specific polymer of the (B) component, a phenol novolak resin includes, for example, a phenol-formaldehyde polycondensate.

[0080] In the cured film-forming composition of the present embodiment, the (B) component polymer may be used in powder form or in solution form in which a purified powder is redissolved in a solvent described later.

[0081] Also, in the cured film-forming composition of the present embodiment, the (B) component polymer may be a mixture of a plurality of types of (B) component polymers.

[0082] <(C) component> The component (C) contained in the curable film-forming composition of the present embodiment is a polymer obtained by polymerizing a monomer containing an N-hydroxymethyl compound or an N-alkoxymethyl (meth)acrylamide compound.

[0083] Examples of such polymers include polymers obtained by copolymerizing a monomer such as N-alkoxymethylacrylamide or N-hydroxymethylacrylamide alone or with a copolymerizable monomer. Examples of such polymers include, for example, poly(N-butoxymethylacrylamide), poly(N-ethoxymethylacrylamide), poly(N-methoxymethylacrylamide), poly(N-hydroxymethylacrylamide), a copolymer of N-butoxymethylacrylamide and styrene, a copolymer of N-butoxymethylacrylamide and methyl methacrylate, a copolymer of N-ethoxymethyl methacrylamide and benzyl methacrylate, and a copolymer of N-butoxymethylacrylamide, benzyl methacrylate and 2-hydroxypropyl methacrylate. The weight average molecular weight of such polymers is from 1,000 to 500,000, preferably from 2,000 to 200,000, more preferably from 3,000 to 150,000, and still more preferably from 3,000 to 50,000.

[0084] These polymers of component (C) can be used alone or in combination of two or more.

[0085] In the curable film-forming composition of the present embodiment, the content of the polymer obtained by polymerizing the monomer containing the N-hydroxymethyl compound or N-alkoxymethyl (meth)acrylamide compound as the component (C) is preferably 10 parts by mass to 150 parts by mass, more preferably 20 parts by mass to 100 parts by mass, based on 100 parts by mass of the total amount of the compound as the component (A) and the polymer of the component (B). When the content of the polymer obtained by polymerizing the monomer containing the N-hydroxymethyl compound or N-alkoxymethyl (meth)acrylamide compound as the component (C) is too small, the solvent resistance and heat resistance of the cured film obtained from the curable film-forming composition decrease, and the sensitivity during photoalignment decreases. On the other hand, when the content is too large, the photoalignment property and storage stability may decrease.

[0086] <Component (D)> The curable film-forming composition of the present embodiment further contains a crosslinking catalyst as the component (D) in addition to the components (A), (B), and (C). As the crosslinking catalyst as the component (D), for example, an acid or a thermal acid generator can be used. This component (D) is effective in promoting the thermosetting reaction of the curable film-forming composition of the present embodiment.

[0087] (D) components include sulfonic acid group-containing compounds, hydrochloric acid or its salts, and compounds that generate acids upon thermal decomposition during pre-baking or post-baking, that is, compounds that generate acids upon thermal decomposition at temperatures from 80 °C to 250 °C, and are not particularly limited. Such compounds include, for example, 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 and other sulfonic acids or their hydrates, salts, etc. Compounds that generate acids upon heating include, for example, bis(tosyloxy)ethane, bis(tosyloxy)propane, bis(tosyloxy)butane, p-nitrobenzyl tosylate, o-nitrobenzyl tosylate, 1,2,3-phenylenetris(methylsulfonate), p-toluenesulfonic acid pyridinium salt, p-toluenesulfonic acid morphonium 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-toluenesulfonate, N-ethyl-p-toluenesulfonamide, and compounds represented by the following formula, etc.

[0088] [Chemical formula]

[0089] [Chemical formula]

[0090] [Chemical]

[0091] [Chemical]

[0092] [Chemical]

[0093] [Chemical]

[0094] In the curable film-forming composition of this embodiment, the content of component (D) is preferably 0.01 part by mass to 10 parts by mass, more preferably 0.1 part by mass to 6 parts by mass, and still more preferably 0.5 part by mass to 5 parts by mass with respect to 100 parts by mass of the total amount of the compound of component (A) and the polymer of component (B). By setting the content of component (D) to 0.01 part by mass or more, sufficient thermosetting properties and solvent resistance can be imparted, and furthermore, high sensitivity to light irradiation can also be imparted.

[0095] <(E) component> The curable film-forming composition of the present invention can also contain, as component (E), a component that improves the adhesiveness of the formed curable film (hereinafter, also referred to as an adhesion-improving component).

[0096] (E) The adhesion improvement component, which is a component, can link the polymerizable functional group of the polymerizable liquid crystal and the crosslinking reaction site of the alignment material by a covalent bond so as to improve the adhesion between the alignment material obtained from the curable film-forming composition of the present invention and the layer of the polymerizable liquid crystal. As a result, the retardation film of the present embodiment formed by laminating the polymerizable liquid crystal cured on the alignment material of the present embodiment can maintain strong adhesion even under high-temperature and high-humidity conditions, and can exhibit high durability against peeling and the like.

[0097] As the component (E), monomers and polymers having a group selected from a hydroxy group and an N-alkoxymethyl group and a polymerizable group are preferable. Examples of such a component (E) include compounds having a hydroxy group and a (meth)acrylic group, compounds having an N-alkoxymethyl group and a (meth)acrylic group, polymers having an N-alkoxymethyl group and a (meth)acrylic group, and the like. Specific examples are shown below.

[0098] As an example of the component (E), a polyfunctional acrylate containing a hydroxy group (hereinafter, also referred to as a hydroxy group-containing polyfunctional acrylate) can be mentioned. Examples of the hydroxy group-containing polyfunctional acrylate which is an example of the component (E) include pentaerythritol triacrylate and dipentaerythritol pentaacrylate.

[0099] As an example of the component (E), a compound having one acrylic group and one or more hydroxy groups can also be mentioned.

[0100] In addition, examples of the compound of the component (E) include a compound having at least one polymerizable group containing a C=C double bond in one molecule and at least one N-alkoxymethyl group.

[0101] Examples of the polymerizable group containing a C=C double bond include an acrylic group, a methacrylic group, a vinyl group, an allyl group, a maleimide group, and the like.

[0102] As the compound having at least one polymerizable group containing a C═C double bond and at least one N-alkoxymethyl group in the molecule, preferably, for example, a compound represented by the following formula (X1) can be mentioned. [Chemical formula] (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)

[0103] 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, N-butoxymethyl (meth) acrylamide and the like. Note that (meth) acrylamide means both methacrylamide and acrylamide.

[0104] As another aspect of the compound having a polymerizable group containing a C═C double bond and an N-alkoxymethyl group in the (E) component, preferably, for example, the following compounds can be mentioned. [Chemical formula]

[0105] In the liquid crystal aligning agent of the embodiment of the present invention, the content of the (E) component is preferably 1 part by mass to 100 parts by mass, more preferably 5 parts by mass to 70 parts by mass with respect to 100 parts by mass of the aligning component which is the (A) component.

[0106] [Solvent] The cured film-forming composition of the present embodiment is mainly used in a solution state dissolved in a solvent. The solvent used at that time contains a C1-C4 alkyl ester of a C1-C4 fatty acid, and any solvent can be used as long as it can dissolve the component (A), the component (B), the component (C), the component (D) as required, and / or other additives described later. Other compositions, types, etc. are not particularly limited.

[0107] As the C1-C4 alkyl ester of the C1-C4 fatty acid, the fatty acid alkyl ester represented by the formula: R 1 COOR 2 (However, R 1 is a hydrogen atom or an alkyl group preferably having 1 to 4 carbon atoms, more preferably 1 or 2 carbon atoms, and R 2 is an alkyl group having 1 to 4 carbon atoms.) is suitable. Preferred specific examples include methyl formate, ethyl formate, n-propyl formate, i-propyl formate, n-butyl formate, i-butyl formate, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, i-propyl propionate, n-butyl propionate, or i-butyl propionate. In particular, methyl acetate, ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, or i-propyl propionate is preferred. One or more of these can be used.

[0108] Examples of the C1-C5 alcohol include methanol, ethanol, n-propanol, i-propanol, n-butanol, s-butanol, t-butanol, n-pentanol, etc. Among them, primary and secondary alcohols are preferred in terms of ease of capping.

[0109] In addition, the cured film-forming composition of the present invention may contain other solvents in addition to the C1-C5 alcohol and the C1-C4 alkyl ester of the C1-C4 fatty acid.

[0110] Specific examples of other solvents include, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-butanone, 3-methyl-2-pentanone, 2-pentanone, 2-heptanone, 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, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone, etc.

[0111] These solvents can be used singly or in combination of two or more.

[0112] <Other Additives> Furthermore, the curable film-forming composition of the present embodiment can contain, as necessary, a sensitizer, a silane coupling agent, a surfactant, a rheology modifier, a pigment, a dye, a storage stabilizer, an antifoaming agent, an antioxidant, etc., as long as the effects of the present invention are not impaired.

[0113] For example, the sensitizer is effective in promoting the photoreaction after forming a thermosetting film using the curable film-forming composition of the present embodiment.

[0114] Examples of other additives include sensitizers such as benzophenone, anthracene, anthraquinone, thioxanthone and the like and their derivatives, and nitrophenyl compounds. Among these, benzophenone derivatives and nitrophenyl compounds are preferred. Specific examples of preferred compounds include N,N-diethylaminobenzophenone, 2-nitrofluorene, 2-nitrofluorenone, 5-nitroacenaphthene, 4-nitrobiphenyl, 4-nitrobenzoic acid, 4-nitrostilbene, 4-nitrobenzophenone, 5-nitroindole and the like. In particular, N,N-diethylaminobenzophenone, which is a derivative of benzophenone, is preferred.

[0115] These sensitizers are not limited to the above. In addition, the sensitizers can be used alone or in combination of two or more compounds.

[0116] The proportion of the sensitizer used in the curable film-forming composition of the present embodiment is preferably 0.1 part by mass to 20 parts by mass, more preferably 0.2 part by mass to 10 parts by mass, based on 100 parts by mass of the total mass of the specific copolymer of component (A) and the acrylic polymer of component (B). If this ratio is too small, the effect as a sensitizer may not be sufficiently obtained, and if it is too large, a decrease in transmittance and roughness of the coating film may occur.

[0117] <Preparation of curable film-forming composition> The curable film-forming composition of the present embodiment contains (A) a compound having a photo-orienting group and any one substituent selected from a hydroxy group, a carboxyl group and an amino group, (B) a hydrophilic polymer having one or more substituents selected from a hydroxy group, a carboxyl group and an amino group, (C) a polymer obtained by polymerizing a monomer containing an N-hydroxymethyl compound or an N-alkoxymethyl (meth)acrylamide compound, (D) a crosslinking catalyst, and a solvent containing both an alcohol having 1 to 5 carbon atoms and an alkyl ester of a fatty acid having 1 to 4 carbon atoms with an alcohol having 1 to 4 carbon atoms. And as long as the effects of the present invention are not impaired, other additives can be contained.

[0118] The mixing ratio of component (A) and component (B) is preferably 5:95 to 60:40 by mass from the viewpoints of liquid crystal alignment property and solvent resistance.

[0119] The content ratio of an alcohol solvent having 1 to 5 carbon atoms and an alkyl ester solvent of a fatty acid having 1 to 4 carbon atoms and having 1 to 4 carbon atoms is preferably 10:90 to 90:10 by mass. Further, when the above-mentioned other solvent is contained, the total amount of the alcohol solvent having 1 to 5 carbon atoms and the alkyl ester solvent of the fatty acid having 1 to 4 carbon atoms and having 1 to 4 carbon atoms in the whole solvent is preferably 30% by mass to 99% by mass.

[0120] When the cured film-forming composition of the present embodiment is used as a solution, the mixing ratio, preparation method, etc. will be described in detail below. The proportion of the solid content in the cured film-forming composition of the present embodiment is not particularly limited as long as each component is uniformly dissolved in the solvent, but it is 1% by mass to 80% by mass, preferably 3% by mass to 60% by mass, and more preferably 5% by mass to 40% by mass. Here, the solid content means the one obtained by removing the solvent from all components of the cured film-forming composition.

[0121] The preparation method of the cured film-forming composition of the present embodiment is not particularly limited. As the preparation method, for example, into the solvent derived from component (B) or component (C), component (A) and, if necessary, component (E) etc. are put, an alkyl ester of a fatty acid having 1 to 4 carbon atoms is put, and then an alcohol solvent having 1 to 5 carbon atoms is put, and then component (D) is put to make a uniform solution, or at an appropriate stage of this preparation method, if necessary, component (E) and other additives are further added and mixed.

[0122] Further, the solution of the prepared cured film-forming composition is preferably filtered using a filter having a pore size of about 0.2 μm and then used.

[0123] <Cured Film, Alignment Material and Phase Difference Material> The solution of the curable film-forming composition of this embodiment is applied onto a substrate (for example, 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 (for example, a resin film such as a triacetyl cellulose (TAC) film, a cycloolefin polymer film, a polyethylene terephthalate film, an acrylic film, etc.) by bar coating, spin coating, flow coating, roll coating, slit coating, spin coating following slit coating, inkjet coating, printing, etc. to form a coating film, and then a cured film can be formed by heating and drying with a hot plate or an oven, etc.

[0124] As the conditions for heating and drying, the crosslinking reaction by the crosslinking agent may proceed to such an extent that the components of the alignment material formed from the cured film do not elute into the polymerizable liquid crystal solution applied thereon. For example, a heating temperature and a heating time appropriately selected from the range of a temperature of 60°C to 200°C and a time of 0.4 minutes to 60 minutes are adopted. The heating temperature and the heating time are preferably 70°C to 160°C and 0.5 minutes to 10 minutes.

[0125] The film thickness of the cured film formed using the curable composition of this embodiment is, for example, 0.05 μm to 5 μm, and can be appropriately selected in consideration of the step difference, optical and electrical properties of the substrate to be used.

[0126] The cured film thus formed can function as a member for aligning an alignment material, that is, a compound having liquid crystallinity such as liquid crystal, by performing polarized UV irradiation.

[0127] As the method of irradiating polarized UV, ultraviolet light or visible light having a wavelength of usually 150 nm to 450 nm is used, and it is performed by irradiating linearly polarized light from a vertical or oblique direction at room temperature or in a heated state.

[0128] Since the alignment layer formed from the curable film composition of this embodiment has solvent resistance and heat resistance, after applying a retardation material composed of a polymerizable liquid crystal solution onto this alignment layer, the retardation material is heated to the phase transition temperature of the liquid crystal to bring it into a liquid crystal state and aligned on the alignment layer. Then, the retardation material in the aligned state is cured as it is to form a retardation material as a layer having optical anisotropy.

[0129] As the retardation material, for example, a liquid crystal monomer having a polymerizable group and a composition containing the same are used. When the substrate forming the alignment layer is a film, the film having the retardation material of this embodiment is useful as a retardation film. The retardation material for forming such a retardation material becomes a liquid crystal state and takes an alignment state such as horizontal alignment, cholesteric alignment, vertical alignment, hybrid alignment, etc. on the alignment layer, and can be properly selected according to the required retardation.

[0130] Also, when manufacturing a patterned retardation material used for a 3D display, on the cured film formed by the above method from the curable film composition of this embodiment, from a predetermined reference through a mask of a line and space pattern, for example, polarized UV exposure is performed at an orientation of +45 degrees, and then, after removing the mask, polarized UV exposure is performed at an orientation of -45 degrees to obtain an alignment layer in which two types of liquid crystal alignment regions with different liquid crystal alignment control directions are formed. Then, after applying a retardation material composed of a polymerizable liquid crystal solution, the retardation material is heated to the phase transition temperature of the liquid crystal to bring it into a liquid crystal state and aligned on the alignment layer. Then, the retardation material in the aligned state is cured as it is to obtain a patterned retardation material in which a plurality of two types of retardation regions with different retardation characteristics are regularly arranged.

[0131] Also, using two substrates having the alignment layer of this embodiment formed as described above, after bonding them through a spacer so that the alignment layers on both substrates face each other, liquid crystal is injected between those substrates to form a liquid crystal display element in which the liquid crystal is aligned. Therefore, the cured film-forming composition of the present embodiment can be suitably used in the production of various retardation materials (retardation films), liquid crystal display elements, and the like.

Examples

[0132] Hereinafter, the present invention will be specifically described by way of examples of the present invention, but the present invention should not be construed as being limited thereto. [Abbreviations used in the examples] The meanings of the abbreviations used in the following examples are as follows. <Raw materials> BMAA: N-butoxymethylacrylamide AIBN: α,α'-azobisisobutyronitrile <Component A> MCA: 4-methoxycinnamic acid

Chemical formula

[0133] < (B) Component> HPC-SSL: hydroxypropyl cellulose < (C) Component> PB-1

Chemical formula

[0134] <Measurement of the Molecular Weight of the Polymer> The molecular weight of the acrylic copolymer in the polymerization example was measured as follows using a gel permeation chromatography (GPC) apparatus (HLC-8320) manufactured by Tosoh Corporation and columns (TSKgel ALPHA4000, TSKgel ALPHA3000) manufactured by Tosoh Corporation. The following number average molecular weight (hereinafter referred to as Mn) and weight average molecular weight (hereinafter referred to as Mw) were expressed as polystyrene conversion values. Column temperature: 40 °C Eluent: Tetrahydrofuran Flow rate: 1.0 mL / min Standard sample for calibration curve preparation: Standard polystyrene (molecular weights 427,000, 190,000, 37,900, 18,100, 5,970, 2,420, 1,010) manufactured by Tosoh Corporation

[0135] <Viscosity Measurement of the Liquid Crystal Alignment Material> Apparatus: Manufactured by Kyoto Electronics Industry Co., Ltd., EMS-1000 Measurement temperature: 25 °C Probe size: 2.0 mm Φ Rotation speed: 700 rpm Measurement time: 1 second

[0136] < (C) <Synthesis of Components> <Polymerization Example-1> 100.0 g of BMAA and 1.0 g of AIBN as a polymerization catalyst were dissolved in 193.5 g of PM and reacted at 80 °C for 20 hours to obtain an acrylic polymer solution. The Mn of the obtained acrylic polymer was 10,000 and the Mw was 23,000. The acrylic polymer solution was gradually dropped into 2000.0 g of hexane to precipitate a solid, and the polymer (PB-1) was obtained by filtration and drying under reduced pressure.

[0137] <Preparation Example 1> (A) As a component, 0.054 g of MCA, ( C )(B) As a component, 0.378 g of PB-1 obtained in Polymerization Example-1, ( B) 0.144 g of HPC-SSL as the (A) component and 0.144 g of PET-30 (manufactured by Nippon Kayaku Co., Ltd.) as the (E) component were mixed, and 2.484 g of PM, 4.968 g of BA, and 0.828 g of IPA as solvents were added thereto, followed by stirring for 1 hour. After visually confirming dissolution, a solution was obtained. Subsequently, the obtained solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent (A-1).

[0138] <Preparation Examples 2 to 6> The operations were carried out in the same manner as in Preparation Example 1 except that the components of the types and blending amounts shown in Table 1 below were used, and (A-2) to (A-5) and (B-1) were prepared.

Table 1

[0139] <Preparation of Catalyst Solution> <Preparation Example 7> 2.0 g of PTSA as the (D) component and 18.0 g of PM as the solvent were added, followed by stirring for 1 hour. After visually confirming dissolution, the solution was filtered through a filter with a pore size of 0.2 μm to prepare a catalyst solution (D-1).

[0140] <Preparation of Hardened Film Forming Composition (Liquid Crystal Aligning Agent)> <Example 1> 2.00 g of A-1 obtained in Preparation Example 1, D 0.06 g of -1 obtained in Preparation Example 7, and 0.60 g of EA as a diluting solvent were added, and the mixture was stirred for 1 minute to obtain a liquid crystal aligning agent AL-1.

[0141] <Example 2> The preparation was carried out in the same manner as in Example 1 except that A-2 obtained in Preparation Example 2 was used, and a liquid crystal aligning agent AL-2 was obtained.

[0142] <Example 3> The preparation was carried out in the same manner as in Example 1 except that A-3 obtained in Preparation Example 3 was used, and a liquid crystal aligning agent AL-3 was obtained.

[0143] <Example 4> Preparation was carried out in the same manner as in Example 1 except that A-4 obtained in Preparation Example 4 was used, and a liquid crystal aligning agent AL-4 was obtained.

[0144] <Example 5> Preparation was carried out in the same manner as in Example 1 except that A-5 obtained in Preparation Example 5 was used, and a liquid crystal aligning agent AL-5 was obtained.

[0145] <Comparative Example 1> Preparation was carried out in the same manner as in Example 1 except that B-1 obtained in Preparation Example 6 was used, and a liquid crystal aligning agent BL-1 was obtained.

[0146] <Preparation of Polymerizable Liquid Crystal Solution for Horizontal Alignment> <Preparation Example 9> 1.57 g of LC-242 (manufactured by BASF), which is a polymerizable liquid crystal for horizontal alignment, 0.047 g of Irgacure 907 (manufactured by BASF), which is a photo radical initiator, and 0.008 g of BYK-361N, which is a leveling agent, were added. Further, 6.55 g of NMP and 9.83 g of cyclopentanone were added as solvents, and the mixture was stirred for 2 hours and confirmed to be visually dissolved to obtain a 9 mass% polymerizable liquid crystal solution LC-1.

[0147] <Formation of Liquid Crystal Alignment Film and Production of Retardation Film> <Example 7> The liquid crystal aligning agent (AL-1) obtained in Example 1 was applied onto a TAC film as a substrate using a bar coater at a Wet film thickness of 10 μm. It was dried by heating at 120 °C for 1 minute in a thermal circulation oven to form a cured film on the film. Next, linearly polarized light of 313 nm was vertically irradiated onto the surface of this cured film with an exposure amount of 10 mJ / cm 2 to form a liquid crystal alignment film. The polymerizable liquid crystal solution LC-1 for horizontal alignment was applied onto the above liquid crystal alignment film using a bar coater at a Wet film thickness of 34 μm. Then, after drying by heating at 120 °C for 2 minutes in an oven, non-polarized light of 365 nm was vertically irradiated with an exposure amount of 500 mJ / cm 2 to cure the polymerizable liquid crystal and produce a retardation film.

[0148] <Examples 8 to 11, Comparative Examples 3> Using (AL-2) to (AL-5) and (BL-1) as the liquid crystal alignment agent, a retardation film was fabricated through the same operations as in Example 7.

[0149] For each of the retardation films fabricated above, evaluation was conducted by the following method. The evaluation results are shown in Table 2.

[0150] <Evaluation of alignment property> The retardation film on the fabricated substrate was sandwiched between a pair of polarizing plates, and the manifestation status of the retardation characteristics under crossed Nicols was observed visually. Those with retardation manifested without defects were marked as ○, and those without manifested retardation were marked as × in the column of "alignment property".

[0151] <Evaluation of adhesion> Using a cutter knife, 100 grids of cuts were made in a grid pattern at 1-mm intervals on the retardation film on the fabricated substrate. After strongly pressing a pressure-sensitive adhesive tape (Nichiban Co., Ltd.'s cellophane tape (registered trademark), 24 mm wide) and then peeling it off at once, evaluation was made based on the number of remaining grids. Those with all remaining were marked as ○, those with some peeled off were marked as △, and those with all peeled off were marked as × in the column of "adhesion".

Table 2

[0152] <Viscosity evaluation of liquid crystal alignment agent> For the liquid crystal alignment agents AL-1 to AL- 5 prepared in Examples 1 to 5 and the BL- 1 prepared in Comparative Example To 1 viscosity measurement was carried out. For the liquid crystal alignment agents obtained in Examples 1 to 5 and Comparative Example 1 after storing the obtained liquid crystal alignment agents at room temperature for a predetermined time, viscosity measurement was similarly carried out and is described in Table 3.

Table 3

[0153] It can be seen from the results in Table 2 that the liquid crystal alignment agent composition can obtain orientation and adhesion. However, from the results in Table 3, by adding a lower alcohol as the solvent composition, it becomes possible to stabilize the viscosity after the preparation of the liquid crystal alignment agent.

Industrial Applicability

[0154] The cured film-forming composition according to the present invention is very useful as an alignment material for forming a liquid crystal alignment film of a liquid crystal display element or an optically anisotropic film provided inside or outside the liquid crystal display element. In particular, it is suitable as a material for forming a patterned retardation material for a 3D display. Furthermore, it is also suitable as a material for forming cured films such as protective films, planarization films, and insulating films in various displays such as thin-film transistor (TFT) type liquid crystal display elements and organic EL elements. In particular, it is suitable as a material for forming an interlayer insulating film of a TFT type liquid crystal element, a protective film for a color filter, or an insulating film of an organic EL element.

Claims

1. (A) A compound having a photo-orienting group which is a functional group capable of photo-binary quantization or photo-isomerization, and any one substituent selected from a hydroxy group, a carboxyl group, and an amino group; (B) A hydrophilic polymer having one or more substituents selected from a hydroxy group, a carboxyl group, and an amino group; (C) A polymer obtained by polymerizing a monomer containing an N-hydroxymethyl or N-alkoxymethyl (meth)acrylamide compound; (D) A crosslinking catalyst, and A curing film-forming composition characterized by containing a solvent containing both an alcohol having 1 to 5 carbon atoms selected from methanol, ethanol, n-propanol, i-propanol, n-butanol, s-butanol, t-butanol, and n-pentanol, and a C1-C4 alkyl ester of a C1-C4 fatty acid.

2. The curing film-forming composition according to claim 1, wherein the photo-orienting group of the component (A) is a cinnamoyl group.

3. The curing film-forming composition according to claim 1, wherein the photo-orienting group of the component (A) is a group having an azobenzene structure.

4. The curing film-forming composition according to any one of claims 1 to 3, wherein the component (A) has two or more hydroxy groups.

5. The curing film-forming composition according to any one of claims 1 to 4, wherein the component (B) is at least one polymer selected from the group consisting of polyether polyol, polyester polyol, polycarbonate polyol, and polycaprolactone polyol.

6. The curing film-forming composition according to any one of claims 1 to 4, wherein the component (B) is cellulose or a derivative thereof.

7. The curable film-forming composition according to any one of claims 1 to 4, wherein component (B) is an acrylic polymer having at least one of a polyethylene glycol ester group and a hydroxyalkyl ester group having 2 to 5 carbon atoms, and at least one of a carboxyl group and a phenolic hydroxy group.

8. The curable film-forming composition according to any one of claims 1 to 4, wherein component (B) is an acrylic polymer having a hydroxyalkyl group in the side chain.

9. The curable film-forming composition according to any one of claims 1 to 8, further comprising an adhesion improving component as component (E).

10. The curable film-forming composition according to any one of claims 1 to 9, wherein the ratio of component (A) to component (B) is 5:95 to 60:40 by mass.

11. The curable film-forming composition according to any one of claims 1 to 10, containing 0.01 to 10 parts by mass of component (D) with respect to 100 parts by mass of the total amount of the compound of component (A) and the polymer of component (B).

12. An alignment material, characterized in that it is obtained by using the curable film-forming composition according to any one of claims 1 to 11.

13. A retardation material, characterized in that it is formed by using a cured film obtained from the curable film-forming composition according to any one of claims 1 to 11.

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