Alignment film, optical film, and image display device

Abstract

To provide an alignment film, an optical film, and an image display device that achieve reduced dust generation and exhibit high alignment characteristics.SOLUTION: An alignment film produced using a cured product of a composition comprising a polyfunctional monomer and an acrylic polymer, wherein the content of the polyfunctional monomer is 30 mass% or more relative to the total mass of solids in the composition, the content of the acrylic polymer is 0.01 to 10.0 mass% relative to the total mass of solids in the composition, and the acrylic polymer satisfies either one of the following conditions 1 and 2: Condition 1: containing no aromatic ring. Condition 2: containing a predetermined mesogenic group.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an alignment film, an optical film, and an image display device. [Background technology]

[0002] Optical films such as optical compensation sheets and retardation films are used in various image display devices to eliminate image coloration or widen the viewing angle. Stretched birefringent films have been used as optical films, but in recent years, it has been proposed to use optical films having a liquid crystal cured layer instead of stretched birefringent films.

[0003] When forming such a liquid crystal cured layer, an alignment film is usually used. For example, Patent Document 1 describes an alignment film obtained by rubbing a cured product of a resin composition for a liquid crystal alignment film, which contains an acrylic copolymer (A), which is a copolymer obtained from raw materials including a bifunctional (meth)acrylate (a1) having a benzene ring structure in the main chain and a monofunctional polymerizable compound (a2), and a solvent (B) ([Claim 1]

[0110] ). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-188610 Summary of the Invention [Problem to be solved by the invention]

[0005] Here, the alignment film is generally used after being given an alignment control force by a rubbing treatment. However, it is known that debris of the alignment film generated during the rubbing treatment may cause bright spot defects in an optical film having a liquid crystal cured layer. Therefore, the present inventors have studied the alignment film described in Patent Document 1 and found that although the alignment of the liquid crystal compound in the cured liquid crystal layer (hereinafter also simply referred to as "alignment") is good, in consideration of the standards for bright spot defects that have arisen in recent years due to improvements in the display performance of various devices and the diversification of uses of display devices, it is highly necessary to suppress the generation of debris from the alignment film (hereinafter also referred to as "dust generation").

[0006] Therefore, an object of the present invention is to provide an alignment film, an optical film, and an image display device that are suppressed from generating dust and have high alignment properties. [Means for solving the problem]

[0007] As a result of intensive research to achieve the above object, the present inventors have found that an alignment film prepared using a cured product of a composition in which a polyfunctional monomer and an acrylic polymer that satisfies predetermined conditions are blended in specific amounts, has reduced dust generation and has high alignment, and have completed the present invention. That is, the present inventors have found that the above problems can be solved by the following configuration.

[0008] [1] An alignment film made using a cured product of a composition containing a polyfunctional monomer and an acrylic polymer, The content of the polyfunctional monomer is 30% by mass or more based on the total mass of the solid content of the composition, the content of the acrylic polymer is 0.01 to 10.0% by mass relative to the total mass of the solid content of the composition; An alignment film, wherein the acrylic polymer satisfies either of the following conditions 1 and 2: Condition 1: No aromatic ring. Requirement 2: The compound has a mesogen group represented by formula (M) described below. [2] The alignment film according to [1], wherein the polyfunctional monomer is a monomer having three or more polymerizable groups. [3] The alignment film according to [2], wherein the polymerizable group is any one of an epoxy group, an acryloyl group, and a methacryloyl group. [4] The alignment film according to any one of [1] to [3], wherein the acrylic polymer has a polymerizable group. [5] The alignment film according to any one of [1] to [4], wherein the acrylic polymer contains a fluorine atom or a silicon atom. [6] The alignment film according to any one of [1] to [5], wherein the weight-average molecular weight of the acrylic polymer is 30,000 or more when the acrylic polymer satisfies condition 1, and 10,000 or more when the acrylic polymer satisfies condition 2. [7] An optical film having an alignment film and a liquid crystal curing layer, The alignment film is the alignment film according to any one of [1] to [6], An optical film, wherein the liquid crystal cured layer is a layer in which the alignment state of a liquid crystal compound is fixed. [8] The liquid crystal curing layer is one or more optically anisotropic layers, The optical film according to [7], wherein at least one optically anisotropic layer has a λ / 4 function. [9] An image display device having the optical film according to [7] or [8].

[10] The image display device according to [9], which is a liquid crystal display device.

[11] The image display device according to

[10] , which is an organic EL display device. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide an alignment film, an optical film, and an image display device that are suppressed from generating dust and have high alignment properties. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below. The following description of the components may be based on typical embodiments of the present invention, but the present invention is not limited to such embodiments. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. In addition, in the present specification, in the numerical ranges described in stages, the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in the numerical ranges described in the present specification, the upper or lower limit value described in a certain numerical range may be replaced with a value shown in the examples. In addition, in this specification, each component may be a single substance corresponding to the component, or two or more substances may be used in combination. Here, when two or more substances are used in combination for each component, the content of that component refers to the total content of the substances used in combination, unless otherwise specified. Furthermore, in this specification, the bonding direction of a divalent group (for example, -CO-O-) is not particularly limited unless the bonding position is clearly stated. For example, when L in XLY is -COO-, if the position bonding to the X side is *1 and the position bonding to the Y side is *2, L may be *1-O-CO-*2 or *1-CO-O-*2.

[0011] [Alignment film] The alignment film of the present invention is an alignment film prepared using a cured product of a composition containing a polyfunctional monomer and an acrylic polymer (hereinafter also referred to as an "alignment film-forming composition"), and more precisely, is an alignment film obtained by subjecting the cured product to a rubbing treatment. In addition, the alignment film of the present invention has a polyfunctional monomer content of 30 mass % or more relative to the total mass of the solid content of the alignment film-forming composition, and a acrylic polymer content of 0.01 to 10.0 mass % relative to the total mass of the solid content of the alignment film-forming composition. In the alignment film of the present invention, the acrylic polymer satisfies either of the following conditions 1 and 2. Condition 1: No aromatic ring. Requirement 2: The compound has a mesogen group represented by formula (M) described below.

[0012] In the present invention, as described above, an alignment film prepared using a cured product of a composition in which a polyfunctional monomer and the above-mentioned acrylic polymer are blended in the above-mentioned mass % each has reduced dust generation and high alignment properties. The reason why these effects are exhibited is not clear in detail, but the present inventors speculate as follows. In other words, by incorporating a polyfunctional monomer in an amount of 30% by mass or more relative to the total mass of the solid content of the composition for forming an alignment film, a three-dimensionally crosslinked cured product was obtained, and resistance to rubbing treatment (especially scrubbing) was improved, which is thought to have suppressed dust generation. Furthermore, it is believed that the incorporation of an acrylic polymer satisfying the above-mentioned condition 1 or 2 in an amount of 0.01 to 10.0 mass % relative to the total mass of the solid content of the composition for forming an alignment film facilitates the generation of an alignment control force by rubbing treatment, thereby enhancing the alignment of the liquid crystal compound. In particular, it is believed that the acrylic polymer satisfying condition 1 does not have an aromatic ring, thereby increasing the mobility of the polymer main chain and thus facilitating the generation of an alignment control force by rubbing treatment. Furthermore, it is believed that the acrylic polymer satisfying condition 2 has a mesogen group with three or more aromatic rings, thereby enhancing the interaction with the liquid crystal compound and improving the alignment control force.

[0013] [Composition for forming alignment film] The composition for forming an alignment film used to prepare the alignment film of the present invention is a composition containing a polyfunctional monomer and an acrylic polymer, as described above.

[0014] <Polyfunctional Monomer> The polyfunctional monomer contained in the composition for forming an alignment film is not particularly limited as long as it is a monomer having two or more identical polymerizable groups. Furthermore, the polyfunctional monomer is preferably a monomer having 3 or more polymerizable groups, more preferably a monomer having 3 to 8 polymerizable groups, and even more preferably a monomer having 3 to 6 polymerizable groups, because this further suppresses dust generation of the alignment film. When the polyfunctional monomer has 3 or more polymerizable groups, it is sufficient that at least two of the polymerizable groups are the same polymerizable group.

[0015] Here, the polymerizable group is not particularly limited, but is preferably a polymerizable group capable of radical polymerization or cationic polymerization. As the radical polymerizable group, a known radical polymerizable group can be used, and preferred examples include an acryloyl group or a methacryloyl group. In this case, it is known that the polymerization rate of an acryloyl group is generally fast, and from the viewpoint of improving productivity, an acryloyl group is preferred, but a methacryloyl group can also be used as the polymerizable group. As the cationically polymerizable group, known cationically polymerizable groups can be used, and specific examples thereof include an alicyclic ether group, a cyclic acetal group, a cyclic lactone group, a cyclic thioether group, a spiro orthoester group, and a vinyloxy group. Among them, an alicyclic ether group or a vinyloxy group is preferred, and an epoxy group, an oxetanyl group, or a vinyloxy group is particularly preferred. Of these polymerizable groups, any one of an epoxy group, an acryloyl group, and a methacryloyl group is preferred.

[0016] Examples of polyfunctional monomers having two or more epoxy groups include alicyclic epoxy compounds having a cyclic aliphatic skeleton and two or more epoxy groups in the molecule, and specifically, compounds represented by the following formula: L1 represents an alkylene group having 2 to 18 carbon atoms, which may have a branched chain and may contain a cyclic skeleton (for example, a cyclohexane ring). Furthermore, a, b, c, d, e, and f each independently represent an integer of 0 to 30, and m1 and n1 each independently represent an integer of 1 to 30.

[0017] [ka] JPEG2025132767000002.jpg3871 JPEG2025132767000003.jpg2677 JPEG2025132767000004.jpg5573

[0018] Examples of polyfunctional monomers having two or more acryloyl groups or methacryloyl groups include trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, dipentaerythritol hexaacrylate, caprolactone-modified dipentaerythritol hexaacrylate, pentaerythritol triacrylate, and pentaerythritol tetraacrylate.

[0019] In the present invention, the polyfunctional monomer contained in the composition for forming an alignment film is preferably a non-liquid crystal compound. Specifically, it is preferably a compound that does not have a mesogen group, as described later in connection with the acrylic polymer.

[0020] Furthermore, as described above, the content of the polyfunctional monomer contained in the composition for forming an alignment film is 30% by mass or more, preferably 40% by mass or more, more preferably 50% by mass or more, and even more preferably 50 to 95% by mass, relative to the total mass of the solid content of the composition for forming an alignment film. The content of the polyfunctional monomer is preferably 5,000 to 500,000 parts by mass, and more preferably 10,000 to 100,000 parts by mass, relative to 100 parts by mass of the acrylic polymer described below.

[0021] <Acrylic polymer> The acrylic polymer contained in the composition for forming an alignment film is an acrylic polymer that satisfies either of the following conditions 1 and 2, as described above. Here, "acrylic polymer" refers to a polymer having, as a repeating unit (monomer unit) constituting the polymer, a repeating unit derived from a monomer having at least one acryloyl group or methacryloyl group (for example, acrylic acid, methacrylic acid, acrylic acid ester, methacrylic acid ester, acrylamide, methacrylamide, etc.).

[0022] Condition 1: No aromatic ring. Requirement 2: The compound has a mesogen group represented by the following formula (M). [ka] Here, in the above formula (M), * indicates the bond position. n represents an integer of 2 or more. Ph 11 and Ph 12 Each independently represents an aromatic ring, and multiple Ph 11 may be the same or different. L 11 represents a single bond or a divalent linking group, and a plurality of L 11 may be the same or different.

[0023] In addition, the aromatic ring specified as "not having" in condition 1 and Ph in the above formula (M) in condition 2 are 11 and Ph 12 Examples of the aromatic ring represented by the formula (I) include aromatic rings having 6 to 20 carbon atoms, and specific examples thereof include aromatic hydrocarbon rings such as a benzene ring, a naphthalene ring, an anthracene ring, and a phenanthroline ring; and aromatic heterocycles such as a furan ring, a pyrrole ring, a thiophene ring, a pyridine ring, a thiazole ring, and a benzothiazole ring.

[0024] In condition 2, n in the formula (M) above represents an integer of 2 or more, preferably an integer of 2 to 5, more preferably an integer of 2 to 4, and even more preferably 2 or 3.

[0025] Also, L in condition 2 11 Examples of the divalent linking group represented by one embodiment of the formula include -CO-, -O-, -CO-O-, -C(=S)O-, -CR 1 R 2 -, -CR 1 R 2 -CR 1 R 2 -, -O-CR 1 R 2-, -CR 1 R 2 -O-CR 1 R 2 -,-CO-O-CR 1 R 2 -, -O-CO-CR 1 R 2 -, -CR 1 R 2 -O-CO-CR 1 R 2 -, -CR 1 R 2 -CO-O-CR 1 R 2 -, -NR 5 -CR 1 R 2 -, and -CO-NR 5 - and others. R 1 , R 2 and R 5 each independently represents a hydrogen atom, a fluorine atom, or an alkyl group having 1 to 12 carbon atoms. Among these, any one of -CO-, -O- and -CO-O- is preferred.

[0026] (Acrylic polymer that meets condition 1) Examples of acrylic polymers that satisfy condition 1, that is, acrylic polymers that do not have an aromatic ring, include polymers that have one or more types of repeating units A represented by the following formula (A). [ka]

[0027] In the above formula (A), R A1 represents a hydrogen atom or a substituent. Also, X is -O-, -S-, or -NR A2 - represents R A2 represents a hydrogen atom or a substituent. Also, L A1 represents a single bond or a divalent linking group. Also, T A1represents a hydrogen atom or a substituent, and may be linked to the main chain of another acrylic polymer.

[0028] In the above formula (A), R A1 represents a hydrogen atom or a substituent. where R A1 The type of the substituent represented by one embodiment of the formula (I) is not particularly limited, and examples thereof include known substituents. Examples of the substituent include a halogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a cyano group, a carboxy group, an alkoxycarbonyl group, and a hydroxyl group. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms, with fluorine and chlorine atoms being preferred. The alkyl group is preferably, for example, a linear alkyl group having 1 to 18 carbon atoms, or a branched or cyclic alkyl group having 3 to 18 carbon atoms, more preferably a linear alkyl group having 1 to 4 carbon atoms, and further preferably a methyl group or an ethyl group. The alkoxy group is, for example, preferably an alkoxy group having 1 to 18 carbon atoms, more preferably an alkoxy group having 1 to 4 carbon atoms, and further preferably a methoxy group or an ethoxy group. Examples of the aryl group include aryl groups having 6 to 12 carbon atoms, such as a phenyl group, an α-methylphenyl group, and a naphthyl group, with a phenyl group being preferred. Examples of the aryloxy group include a phenoxy group, a naphthoxy group, an imidazoyloxy group, a benzimidazoyloxy group, a pyridin-4-yloxy group, a pyrimidinyloxy group, a quinazolinyloxy group, a purinyloxy group, and a thiophen-3-yloxy group. Examples of the alkoxycarbonyl group include a methoxycarbonyl group and an ethoxycarbonyl group. R A1 is preferably a hydrogen atom or an alkyl group, and more preferably a hydrogen atom or a methyl group.

[0029] In the above formula (A), X is —O—, —S—, or —NR A2 - represents R A2 represents a hydrogen atom or a substituent. where R A2 The substituents represented by one embodiment of the above R A1 In addition, R A2 is preferably a hydrogen atom or an alkyl group. X is -O- or -NR A2 It is preferably -, more preferably -O- or -NH-, and further preferably -O-.

[0030] In the above formula (A), L A1 represents a single bond or a divalent linking group. where L A1 Examples of the divalent linking group represented by one embodiment of the formula (1) include an optionally substituted divalent aliphatic hydrocarbon group, -O-, -S-, -N(Q)-, -CO-, or a combination thereof. Q represents a hydrogen atom or a substituent. Examples of the divalent aliphatic hydrocarbon group include alkylene groups having 1 to 10 carbon atoms, alkenylene groups having 1 to 10 carbon atoms, and alkynylene groups having 1 to 10 carbon atoms. Examples of groups combining these include groups combining at least two or more selected from the group consisting of the above-mentioned divalent aliphatic hydrocarbon groups, -O-, -S-, -N(Q)-, and -CO-, such as the divalent aliphatic hydrocarbon group -O- and the divalent hydrocarbon group -N(Q)-. L A1is preferably a divalent linking group formed by combining at least two or more groups selected from the group consisting of a linear alkylene group having 1 to 10 carbon atoms which may have a substituent, a branched alkylene group having 3 to 10 carbon atoms which may have a substituent, a cyclic alkylene group having 3 to 10 carbon atoms which may have a substituent, -O-, and -N(Q)-, and more preferably a divalent linking group formed by combining at least two or more groups selected from the group consisting of a linear alkylene group having 1 to 10 carbon atoms which may have a substituent, a cyclic alkylene group having 3 to 10 carbon atoms which may have a substituent, -O-, and -NH-. The substituents that the divalent aliphatic hydrocarbon group may have and the substituents represented by one embodiment of Q include the substituents represented by the above R A1 Examples of the substituents include the groups exemplified in one embodiment of the above.

[0031] In the above formula (A), T A1 represents a hydrogen atom or a substituent, and may be linked to the main chain of another acrylic polymer. where T A1 The substituents represented by one embodiment of the above R A1 Examples of the substituent include the groups exemplified as the substituents represented by one embodiment of the formula (1) and polymerizable groups. Examples of the polymerizable group include the same polymerizable groups as those described above for the polyfunctional monomer.

[0032] Specific examples of the repeating unit A represented by the above formula (A) include the following. The acrylic polymer satisfying the condition 1 may have one or more types of repeating unit A. [ka]

[0033] (Acrylic polymer that meets condition 2) Examples of acrylic polymers that satisfy condition 2, i.e., acrylic polymers having a mesogen group represented by the above formula (M), include polymers having one or more types of repeating units B represented by the following formula (B): [ka]

[0034] In the above formula (B), R B1 represents a hydrogen atom or a substituent. Also, X is -O-, -S-, or -NR B2 - represents R B2 represents a hydrogen atom or a substituent. Also, L B1 and L B2 each independently represents a single bond or a divalent linking group. Furthermore, Mes represents a mesogenic group represented by formula (M) explained in the above-mentioned condition 2. Also, T B1 represents a hydrogen atom or a substituent, and may be linked to the main chain of another acrylic polymer.

[0035] In the above formula (B), R B1 represents a hydrogen atom or a substituent. where R B1 Examples of the substituent represented by one embodiment of the formula (A) include R A1 Examples of the substituents include the groups exemplified in one embodiment of the above. Also, R B1 is preferably a hydrogen atom or an alkyl group, and more preferably a hydrogen atom or a methyl group.

[0036] In the above formula (B), X is —O—, —S—, or —NR B2 - represents R B2 represents a hydrogen atom or a substituent. where R B2 Examples of the substituent represented by one embodiment of the formula (A) include R A1 In addition, R B2is preferably a hydrogen atom or an alkyl group. X is -O- or -NR B2 It is preferably -, more preferably -O- or -NH-, and further preferably -O-.

[0037] In the above formula (B), L B1 and L B2 each independently represents a single bond or a divalent linking group. where L B1 and L B2 As a divalent linking group represented by one embodiment of the formula (A), L A1 Examples of the divalent linking group include the groups exemplified as the divalent linking group represented by one embodiment of the formula (1).

[0038] In the above formula (B), Mes represents a mesogenic group represented by formula (M) explained in the above-mentioned condition 2.

[0039] In the above formula (B), T B1 represents a hydrogen atom or a substituent, and may be linked to the main chain of another acrylic polymer. where T B1 Examples of the substituent represented by one embodiment of the formula (A) include R A1 Examples of the substituent include the groups exemplified as the substituents represented by one embodiment of the formula (1) and polymerizable groups. Examples of the polymerizable group include the same polymerizable groups as those described above for the polyfunctional monomer.

[0040] Specific examples of the repeating unit A represented by the above formula (B) include the following. The acrylic polymer satisfying the condition 2 may have one or more types of repeating unit B. [ka]

[0041] In the present invention, it is preferable that the acrylic polymer satisfying the above-mentioned condition 1 or 2 has a polymerizable group, because this further suppresses dust generation from the alignment film and improves adhesion between the alignment film and the cured liquid crystal layer. For example, when the acrylic polymer is a polymer having one or more repeating units A represented by the above formula (A), T A1 is preferably a polymerizable group, more preferably a polymerizable group capable of radical polymerization or cation polymerization, and further preferably any one of an epoxy group, an acryloyl group, and a methacryloyl group.

[0042] In addition, in the present invention, for reasons of further improving the orientation, the acrylic polymer satisfying the above-mentioned condition 1 or 2 preferably contains a fluorine atom or a silicon atom, and more preferably further contains a repeating unit containing a fluorine atom or a silicon atom. The fluorine atom or silicon atom may be contained in the repeating unit A or B described above. Furthermore, when the acrylic polymer satisfying the above-mentioned condition 1 or 2 further has a repeating unit containing a fluorine atom or a silicon atom, the content of the repeating unit is preferably 10 to 80 mass %, more preferably 20 to 65 mass %, and even more preferably 30 to 50 mass %, based on the total repeating units of the acrylic polymer.

[0043] (fluorine atom-containing repeating unit) An example of a repeating unit containing a fluorine atom is a repeating unit C represented by the following formula (C). [ka]

[0044] In the above formula (C), R C1 represents a hydrogen atom or a substituent. Also, X is -O-, -S-, or -NR C2 - represents R C2 represents a hydrogen atom or a substituent. In addition, in the above formula (C), L C1 represents a single bond or a divalent linking group. In the above formula (C), Y represents a hydrogen atom or a fluorine atom, and m represents an integer of 2-20.

[0045] In the above formula (C), R C1 represents a hydrogen atom or a substituent. where R C1 Examples of the substituent represented by one embodiment of the formula (A) include R A1 Examples of the substituents include the groups exemplified in one embodiment of the above. Also, R C1 is preferably a hydrogen atom or an alkyl group, and more preferably a hydrogen atom or a methyl group.

[0046] In the above formula (C), X is —O—, —S—, or —NR C2 - represents R C2 represents a hydrogen atom or a substituent. where R C2 Examples of the substituent represented by one embodiment of the formula (A) include R A1 In addition, R C2 is preferably a hydrogen atom or an alkyl group. X is -O- or -NR C2 It is preferably -, more preferably -O- or -NH-, and further preferably -O-.

[0047] In the above formula (C), L C1 represents a single bond or a divalent linking group. where L C1 As a divalent linking group represented by one embodiment of the formula (A), L A1 Examples of the divalent linking group include the groups exemplified as the divalent linking group represented by one embodiment of the formula (1). L C1 is preferably a linear alkylene group having 1 to 10 carbon atoms.

[0048] In the above formula (C), Y represents a hydrogen atom or a fluorine atom, and is preferably a hydrogen atom.

[0049] In the above formula (C), m represents an integer of 2 to 20, preferably an integer of 3 to 12, and more preferably an integer of 4 to 8.

[0050] Specific examples of repeating units containing a fluorine atom include repeating units represented by the following formulae C-1 to C-8. [ka] JPEG2025132767000012.jpg37132

[0051] (Repeating units containing silicon atoms) Examples of the repeating unit containing a silicon atom include repeating unit D represented by the following formula (D). [ka]

[0052] In the above formula (D), R D1 represents a hydrogen atom or a substituent. Also, X is -O-, -S-, or -NR D2 - represents R D2 represents a hydrogen atom or a substituent. Also, L D1 represents a p+1 valent linking group, where p represents an integer of 2 or greater. Also, R 11 , R 12 , and ,R 13 each independently represents an alkyl group, an alkenyl group, an aryl group, or an alkylenearyl group, which may have a substituent.

[0053] In the above formula (D), R D1 represents a hydrogen atom or a substituent. where R D1 Examples of the substituent represented by one embodiment of the formula (A) include RA1 Examples of the substituents include the groups exemplified in one embodiment of the above. Also, R D1 is preferably a hydrogen atom or an alkyl group, and more preferably a hydrogen atom or a methyl group.

[0054] In the above formula (D), X is —O—, —S—, or —NR D2 - represents R D2 represents a hydrogen atom or a substituent. where R D2 Examples of the substituent represented by one embodiment of the formula (A) include R A1 In addition, R D2 is preferably a hydrogen atom or an alkyl group. X is -O- or -NR D2 It is preferably -, more preferably -O- or -NH-, and further preferably -O-.

[0055] In the above formula (D), p represents an integer of 2 or more, preferably an integer of 3 or more, more preferably an integer of 3 to 6, and even more preferably an integer of 3 to 5.

[0056] In the above formula (D), L D1 represents a p+1-valent linking group. Suitable examples of the p+1-valent linking group include p+1-valent hydrocarbon groups having 1 to 10 carbon atoms which may have a substituent, in which some of the carbon atoms constituting the hydrocarbon group may be substituted with heteroatoms. The substituent that the hydrocarbon group may have is, for example, R A1 Among them, an alkyl group is preferable, a linear alkyl group having 1 to 4 carbon atoms is more preferable, and a methyl group or an ethyl group is even more preferable. Examples of heteroatoms that may substitute a portion of the carbon atoms include silicon atoms, oxygen atoms, and nitrogen atoms. L D1Examples of the group include a group represented by the following structural formula K-1-L, a group represented by the structural formula K-2-L, and a group represented by the structural formula K-3-L. In the sub-structural formulas, * represents the bonding position with X in formula (D), and ** represents -SiR in formula (D). 11 R 12 R 13 represents the bonding position with the group represented by the formula:

[0057] [ka]

[0058] In the above formula (D), R 11 , R 12 , and ,R 13 Each of R in the formula (A) represents an alkyl group, an alkenyl group, an aryl group, or an alkylenearyl group, which may have a substituent. A1 Among them, a halogen atom, an alkyl group, or an alkoxy group is preferable. Examples of the alkyl group include linear alkyl groups having 1 to 18 carbon atoms and branched or cyclic alkyl groups having 3 to 18 carbon atoms. Specific examples include methyl, ethyl, propyl, butyl, isopropyl, tert-butyl, and cyclohexyl groups. The alkenyl group includes, for example, alkenyl groups having 2 to 12 carbon atoms. The aryl group may, for example, be an aryl group having 6 to 12 carbon atoms. The alkylenearyl group may, for example, be an alkylenearyl group having 7 to 30 carbon atoms. R 11 , R 12 , and ,R 13 are preferably all alkyl groups.

[0059] Specific examples of the repeating unit containing a silicon atom include repeating units corresponding to the monomers represented by the following K-1 to K-33. The monomer represented by the following formula K-29 is a mixture of monomers with different numbers of -(O-Si(CH3)2)-, and is therefore expressed as an average value of n ≈ 11. The same applies to the monomer represented by the following formula K-30.

[0060] [ka]

[0061] [ka]

[0062] In the present invention, when the acrylic polymer satisfies the above-mentioned condition 1, the weight average molecular weight is preferably 30,000 or more, more preferably 30,000 to 80,000, and even more preferably 30,000 to 60,000, for the reason that the orientation is further improved. For the same reason, when the acrylic polymer satisfies the above-mentioned condition 2, the weight average molecular weight is preferably 10,000 or more, more preferably 10,000 to 50,000, and even more preferably 10,000 to 30,000. Here, the weight average molecular weight in the present invention is a value measured by gel permeation chromatography (GPC) under the following conditions. Solvent (eluent): THF (tetrahydrofuran) ·Device name: TOSOH HLC-8320GPC Column: Three TOSOH TSKgel Super HZM-H (4.6 mm x 15 cm) columns connected together Column temperature: 40℃ Sample concentration: 0.1% by mass ·Flow rate: 1.0ml / min Calibration curve: TOSOH TSK standard polystyrene. Calibration curves are based on seven samples with Mw = 2,800,000 to 1,050 (Mw / Mn = 1.03 to 1.06).

[0063] In the present invention, the content of the acrylic polymer contained in the composition for forming an alignment film is, as described above, 0.01 to 10.0 mass % relative to the total mass of the solid content of the composition for forming an alignment film, preferably 0.02 to 8.0 mass %, more preferably 0.04 to 6.0 mass %, and even more preferably 0.05 to 2.0 mass %.

[0064] <Other ingredients> The composition for forming an alignment film may contain components other than the above-mentioned polyfunctional monomer and acrylic polymer, for example, a monofunctional monomer, a thermal acid generator, a polymerization initiator, a solvent, etc., which will be described later.

[0065] (monofunctional monomer) The composition for forming an alignment film may contain a monofunctional monomer having one polymerizable group. Here, examples of the polymerizable group include the same polymerizable groups as those explained in the above-mentioned polyfunctional monomer. Examples of such monofunctional monomers having one polymerizable group include cyclic ethers such as 1,2-epoxycyclohexane, 1,4-epoxycyclohexane, 1-methyl-1,2-epoxycyclohexane, 2,3-epoxynorbornane, and 1,3-epoxypropane; and acrylate monomers such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and 2-hydroxy-3-phenoxypropyl acrylate.

[0066] (thermal acid generator) When the above-mentioned polyfunctional monomer has a cationically polymerizable group (e.g., an epoxy group), the composition for forming an alignment film preferably contains a thermal acid generator, i.e., a catalyst that generates an acid when heated and cationic polymerizes the epoxy group through the action of the acid, from the viewpoint of curing the polyfunctional monomer. The thermal acid generator is not particularly limited as long as it can generate an acid by heat, and examples thereof include onium salts such as sulfonium salts, benzothiazolium salts, ammonium salts, and phosphonium salts. Specific examples of thermal acid generators include salts of a cation selected from benzyl(4-hydroxyphenyl)methylsulfonium, (4-acetoxyphenyl)dimethylsulfonium, (4-hydroxyphenyl)dimethylsulfonium, (2-methylbenzyl)(4-hydroxyphenyl)methylsulfonium, (1-naphthylmethyl)(4-hydroxyphenyl)methylsulfonium, and benzyl(4-acetoxyphenyl)methylsulfonium, and an anion selected from tris(pentafluoroethyl)trifluorophosphate, hexafluorophosphate, tetrafluoroborate, tetrakis(pentafluorophenyl)borate, hexafluoroantimonate, p-toluenesulfonate, dodecylbenzenesulfonate, trifluoromethanesulfonate, and perfluorobutanesulfonate.

[0067] (Polymerization initiator) When the above-mentioned polyfunctional monomer has a radical polymerizable group (e.g., an acryloyl group, a methacryloyl group, etc.), the composition for forming an alignment film preferably contains a polymerization initiator from the viewpoint of curing the polyfunctional monomer. The polymerization initiator is not particularly limited, and examples thereof include a thermal polymerization initiator and a photopolymerization initiator depending on the type of polymerization reaction. The polymerization initiator is preferably a photopolymerization initiator that can initiate a polymerization reaction by irradiation with ultraviolet light. Examples of photopolymerization initiators include α-carbonyl compounds, acyloin ethers, α-hydrocarbon-substituted aromatic acyloin compounds, polynuclear quinone compounds, combinations of triarylimidazole dimers and p-aminophenyl ketones, acridine and phenazine compounds, oxadiazole compounds, and acylphosphine oxide compounds.

[0068] (solvent) The composition for forming an alignment film preferably contains a solvent from the viewpoint of workability when forming an alignment film. Examples of solvents include ketones (e.g., acetone, 2-butanone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone), ethers (e.g., dioxane and tetrahydrofuran), aliphatic hydrocarbons (e.g., hexane), alicyclic hydrocarbons (e.g., cyclohexane), aromatic hydrocarbons (e.g., toluene, xylene, and trimethylbenzene), halogenated carbons (e.g., dichloromethane, dichloroethane, dichlorobenzene, and chlorotoluene), esters (e.g., methyl acetate, ethyl acetate, and butyl acetate), water, alcohols (e.g., ethanol, isopropanol, butanol, and cyclohexanol), cellosolves (e.g., methyl cellosolve and ethyl cellosolve), cellosolve acetates, sulfoxides (e.g., dimethyl sulfoxide), and amides (e.g., dimethylformamide and dimethylacetamide). The solvent may be used alone or in combination of two or more kinds.

[0069] [Method for producing alignment film] The alignment film of the present invention is a film produced using the cured product of the above-mentioned composition for forming an alignment film, and the manufacturing procedure thereof is not particularly limited. For example, a method of applying the composition for forming an alignment film onto a support, forming a coating film on the support, curing the coating film, and then performing a rubbing treatment to form an alignment film can be mentioned. The method for applying the composition for forming an alignment film onto the support is not particularly limited, and examples thereof include wire bar coating, extrusion coating, direct gravure coating, reverse gravure coating, and die coating. The method for curing the coating film is not particularly limited, and examples thereof include light irradiation treatment and heat treatment, with light irradiation being preferred. After the composition for forming an alignment film is applied to the support, the support to which the composition for forming an alignment film has been applied may be subjected to a drying treatment to remove the solvent, if necessary.

[0070] <Rubbing process> The rubbing step is a step of subjecting the cured product of the alignment film-forming composition to a rubbing treatment. Here, the rubbing treatment can be a treatment method that is widely used as a liquid crystal alignment treatment step for liquid crystal display devices, in which the surface of the alignment film is rubbed in a certain direction with paper, gauze, felt, rubber, nylon, polyester fiber, or the like to obtain alignment.

[0071] The thickness of the alignment film of the present invention is not particularly limited, but is preferably 0.2 to 1.0 μm, more preferably 0.4 to 0.8 μm.

[0072] [Optical film] The optical film of the present invention is an optical film having the above-described alignment film of the present invention and a liquid crystal cured layer. The liquid crystal cured layer of the optical film of the present invention is a layer in which the alignment state of the liquid crystal compound is fixed.

[0073] [Liquid crystal hardening layer] As described above, the liquid crystal cured layer of the optical film of the present invention is a layer in which the orientation state of the liquid crystal compound is fixed, and is preferably a layer formed by applying a liquid crystal cured layer-forming composition to the coating film formed by horizontally aligning, vertically aligning, tilting, or twisting the liquid crystal compound and fixing that state. Furthermore, as described in WO2021 / 033640, the liquid crystal cured layer may have multiple orientation states in a single layer, such as a first region in which the orientation state of the liquid crystal compound is fixed in a twisted orientation along a helical axis extending along the thickness direction, and a second region in which the orientation state of the liquid crystal compound is fixed in a homogeneous orientation (horizontal orientation). The cured liquid crystal layer is more preferably an optically anisotropic layer, in which case it is no longer necessary to exhibit liquid crystallinity after it has been formed into a layer. Furthermore, the optically anisotropic layer may be formed from a layer including a plurality of liquid crystal cured layers, as will be described later.

[0074] <Liquid crystal compounds> The liquid crystal compound contained in the composition for forming a liquid crystal cured layer preferably has a polymerizable group. Here, examples of the polymerizable group include the same polymerizable groups as those explained in the above-mentioned polyfunctional monomer.

[0075] The liquid crystal compound is not particularly limited, and examples thereof include compounds that can be aligned in any of homeotropic alignment, homogeneous alignment, hybrid alignment, and cholesteric alignment. Generally, liquid crystal compounds can be classified into rod-shaped and discotic types based on their shape. Each of these types can be further divided into low-molecular-weight and high-molecular-weight types. A high-molecular-weight compound generally refers to a compound with a degree of polymerization of 100 or more (see "Polymer Physics: Phase Transition Dynamics," by Masao Doi, p. 2, Iwanami Shoten, 1992). While any liquid crystal compound can be used in the present invention, rod-shaped or discotic liquid crystal compounds (discotic liquid crystal compounds) are preferred. Furthermore, liquid crystal compounds that are monomers or have a relatively low molecular weight with a degree of polymerization of less than 100 are preferred.

[0076] Preferred examples of rod-shaped liquid crystal compounds include those described in claim 1 of JP-A-11-513019 or paragraphs

[0026] to

[0098] of JP-A-2005-289980. Preferred examples of discotic liquid crystal compounds include those described in paragraphs

[0020] to

[0067] of JP-A-2007-108732 or paragraphs

[0013] to

[0108] of JP-A-2010-244038.

[0077] As the liquid crystal compound, a liquid crystal compound with reverse wavelength dispersion can be used. Here, in this specification, the liquid crystal compound having "reverse wavelength dispersion" refers to a compound in which, when the in-plane retardation (Re) value of a retardation film produced using the compound is measured at a specific wavelength (visible light range), the Re value becomes equal to or increases as the measured wavelength increases.

[0078] The reverse wavelength dispersion liquid crystal compound is not particularly limited as long as it can form a reverse wavelength dispersion film, and examples thereof include compounds represented by general formula (I) described in JP-A-2008-297210 (particularly, compounds described in paragraphs

[0034] to

[0039] ), compounds represented by general formula (1) described in JP-A-2010-084032 (particularly, compounds described in paragraphs

[0067] to

[0073] ), and compounds represented by general formula (1) described in JP-A-2016-081035 (particularly, compounds described in paragraphs

[0043] to

[0055] ). Further examples include the compounds described in paragraphs

[0027] to

[0100] of JP 2011-006360 A, paragraphs

[0028] to

[0125] of JP 2011-006361 A, paragraphs

[0034] to

[0298] of JP 2012-207765 A, paragraphs

[0016] to

[0345] of JP 2012-077055 A, paragraphs

[0017] to

[0072] of WO12 / 141245 A, paragraphs

[0021] to

[0088] of WO12 / 147904 A, and paragraphs

[0028] to

[0115] of WO14 / 147904 A.

[0079] <Polymerization initiator> The liquid crystal cured layer-forming composition preferably contains a polymerization initiator. Examples of the polymerization initiator include those described above in the composition for forming an alignment film.

[0080] <Solvent> The composition for forming a liquid crystal cured layer preferably contains a solvent from the viewpoint of workability when forming the liquid crystal cured layer. Examples of the solvent include those described above in the composition for forming an alignment film.

[0081] <Leveling agent> The composition for forming a liquid crystal cured layer preferably contains a leveling agent from the viewpoint of keeping the surface of the liquid crystal cured layer smooth and facilitating alignment control. As such a leveling agent, a fluorine-based leveling agent or a silicon-based leveling agent is preferred because of the high leveling effect relative to the amount added. Examples of the leveling agent include compounds described in paragraphs

[0079] to

[0102] of JP-A No. 2007-069471, compounds represented by general formula (I) described in JP-A No. 2013-047204 (particularly compounds described in paragraphs

[0020] to

[0032] ), compounds represented by general formula (I) described in JP-A No. 2012-211306 (particularly compounds described in paragraphs

[0022] to

[0029] ), liquid crystal alignment promoters represented by general formula (I) described in JP-A No. 2002-129162 (particularly compounds

[0076] to

[0078] and

[0082] to

[0084] ), and the compounds represented by general formulas (I), (II) and (III) described in JP-A-2005-099248 (particularly the compounds described in paragraphs

[0092] to

[0096] ).

[0082] <Other ingredients> The liquid crystal cured layer-forming composition may contain other components in addition to the above-mentioned components. Examples of the other components include a chiral agent, a tilt angle control agent, an alignment aid, a plasticizer, and a crosslinking agent. In addition, the composition may contain an ionic compound, a conductive polymer, or the like as an antistatic agent.

[0083] The thickness of the liquid crystal cured layer is not particularly limited, but is preferably 0.7 to 2.5 μm, more preferably 0.9 to 2.2 μm, from the viewpoint of making the device thinner.

[0084] The alignment state of the liquid crystal compound in the cured liquid crystal layer of the optical film of the present invention is not particularly limited, and may be any of horizontal alignment, vertical alignment, tilt alignment, and twist alignment. Furthermore, the layer may have multiple orientation states, such as the liquid crystal cured layer described in WO2021 / 033640, which has, along the thickness direction, a first region in which the orientation state of liquid crystal compounds twisted along a helical axis extending along the thickness direction is fixed, and a second region in which the orientation state of liquid crystal compounds homogeneously oriented (horizontally oriented) is fixed. In this specification, the term "horizontal alignment" means that the major surface of the cured liquid crystal layer (or, when the cured liquid crystal layer is formed on a member such as a support or an alignment film, the surface of the member) is parallel to the long axis direction of the liquid crystal compound. In addition, in this specification, the term "vertical alignment" means that the main surface of the cured liquid crystal layer (or, when the cured liquid crystal layer is formed on a member such as a support or an alignment film, the surface of the member) is perpendicular to the long axis direction of the liquid crystal compound. It is not required that the liquid crystal molecules are strictly parallel, but in this specification, the term "alignment" means that the angle between the long axis direction of the liquid crystal compound and the main surface of the cured liquid crystal layer is less than 10°.

[0085] The liquid crystal cured layer is preferably an optically anisotropic layer.

[0086] The optically anisotropic layer including the liquid crystal cured layer formed using the alignment film of the present invention preferably has a λ / 4 function. Here, "having a λ / 4 function" means a function of converting linearly polarized light of a specific wavelength into circularly polarized light (or circularly polarized light into linearly polarized light). An optically anisotropic layer having a λ / 4 function can be suitably used as a λ / 4 plate. The optically anisotropic layer may have a plurality of liquid crystal cured layers.

[0087] Examples of optically anisotropic layers include a positive A plate, a positive C plate, and an optically anisotropic layer having, along the thickness direction, a first region in which the orientation state of liquid crystal compounds twisted along a helical axis extending along the thickness direction is fixed, and a second region in which the orientation state of liquid crystal compounds homogeneously oriented (horizontally oriented) is fixed (hereinafter, this embodiment will also be referred to as "optically anisotropic layer A").

[0088] Here, the positive A plate and the positive C plate are defined as follows: When the refractive index in the in-plane direction of the slow axis (the direction in which the in-plane refractive index is greatest) of the film is nx, the refractive index in the direction perpendicular to the in-plane slow axis is ny, and the refractive index in the thickness direction is nz, a positive A plate satisfies the relationship of formula (A1), and a positive C plate satisfies the relationship of formula (C1). Note that a positive A plate has a positive Rth value, and a positive C plate has a negative Rth value. Formula (A1) nx>ny≒nz Formula (C1) nz>nx≒ny The above "≒" includes not only the case where the two are completely identical, but also the case where the two are substantially identical. Regarding "substantially the same," for a positive A plate, "ny≒nz" ​​includes, for example, when (ny-nz)×d (where d is the film thickness) is -10 to 10 nm, preferably -5 to 5 nm, and "nx≒nz" includes, for example, when (nx-nz)×d (where d is the film thickness) is -10 to 10 nm, preferably -5 to 5 nm. For a positive C plate, "nx≒ny" includes, for example, when (nx-ny)×d (where d is the film thickness) is 0 to 10 nm, preferably 0 to 5 nm.

[0089] When the liquid crystal cured layer of the optical film of the present invention is a positive A plate, from the viewpoint of functioning as a λ / 4 plate, Re(550) is preferably 100 to 180 nm, more preferably 120 to 160 nm, still more preferably 130 to 150 nm, and particularly preferably 130 to 145 nm.

[0090] An optically anisotropic layer (optically anisotropic layer A) having, along the thickness direction, a first region in which the orientation state of liquid crystal compounds twisted along a helical axis extending along the thickness direction is fixed, and a second region in which the orientation state of liquid crystal compounds homogeneously oriented (horizontally oriented) is fixed will be described in detail. When the thickness of the first region of the optically anisotropic layer A is d1 (nm) and the refractive index anisotropy of the first region measured at a wavelength of 550 nm is Δn1, it is preferable that the first region satisfies the following formula (1-1) in order to enable the optically anisotropic layer to be suitably applied to a circular polarizing plate. Formula (1-1) 100nm≦Δn1d1≦240nm Among these, it is more preferable to satisfy formula (1-2), and it is even more preferable to satisfy formula (1-3). Formula (1-2) 120nm≦Δn1d1≦220nm Formula (1-3) 140nm≦Δn1d1≦200nm The refractive index anisotropy Δn1 means the refractive index anisotropy of the first region.

[0091] The absolute value of the twist angle of the liquid crystal compound in the first region is not particularly limited, but is preferably 60 to 120°, more preferably 70 to 110°, in order to enable the optically anisotropic layer to be suitably applied to a circular polarizer. The twist angle is measured using an Axoscan manufactured by Axometrics and its instrument analysis software.

[0092] Furthermore, when the thickness of the second region of the optically anisotropic layer A is d2 (nm) and the refractive index anisotropy of the second region measured at a wavelength of 550 nm is Δn2, it is preferable that the second region satisfies the following formula (2-1), in order to make the optically anisotropic layer suitable for use in a circular polarizer. Formula (2-1) 100nm≦Δn2d2≦240nm Among these, it is more preferable to satisfy the formula (2-2), and it is even more preferable to satisfy the formula (2-3). Formula (2-2) 120nm≦Δn2d2≦220nm Formula (2-3) 140nm≦Δn2d2≦200nm The refractive index anisotropy Δn2 means the refractive index anisotropy of the second region.

[0093] [Support] The optical film of the present invention may have a support for supporting the above-mentioned alignment film. The type of support is not particularly limited, and known supports can be used. A transparent support is particularly preferred. The transparent support refers to a support having a visible light transmittance of 60% or more, preferably 80% or more, and more preferably 90% or more.

[0094] Examples of the support include a glass substrate and a polymer film. Examples of polymer film materials include cellulose-based polymers; acrylic polymers containing acrylate ester polymers such as polymethyl methacrylate and lactone ring-containing polymers; thermoplastic norbornene-based polymers; polycarbonate-based polymers; polyester-based polymers such as polyethylene terephthalate and polyethylene naphthalate; styrene-based polymers such as polystyrene and acrylonitrile-styrene copolymers; polyolefin-based polymers such as polyethylene, polypropylene, and ethylene-propylene copolymers; vinyl chloride-based polymers; amide-based polymers such as nylon and aromatic polyamides; imide-based polymers; sulfone-based polymers; polyethersulfone-based polymers; polyetheretherketone-based polymers; polyphenylene sulfide-based polymers; vinylidene chloride-based polymers; vinyl alcohol-based polymers; vinyl butyral-based polymers; arylate-based polymers; polyoxymethylene-based polymers; epoxy-based polymers; or mixtures of these polymers. The support is preferably peelable.

[0095] [Image display device] The image display device of the present invention is an image display device having the optical film of the present invention. The display element used in the image display device is not particularly limited, and examples thereof include a liquid crystal cell, an organic electroluminescence (hereinafter abbreviated as "EL (Electro Luminescence)") display panel, and a plasma display panel. The image display device is preferably a liquid crystal display device using a liquid crystal cell as a display element, or an organic EL display device using an organic EL display panel as a display element.

[0096] [Liquid crystal display device] A liquid crystal display device, which is an example of an image display device, is a liquid crystal display device having a polarizing plate formed using the optical film of the present invention and a liquid crystal cell. Of the polarizing plates provided on both sides of the liquid crystal cell, it is preferable to use the above-mentioned polarizing plate as the front-side polarizing plate, and it is more preferable to use the above-mentioned polarizing plate as the front-side and rear-side polarizing plates.

[0097] [Organic EL display device] An organic EL display device, which is one example of an image display device, may have, in this order from the viewing side, a polarizer, a λ / 4 plate obtained from the optical film of the present invention, and an organic EL display panel. An organic EL display panel is a display panel configured using organic EL elements each having an organic light-emitting layer (organic electroluminescence layer) sandwiched between electrodes (a cathode and an anode). The configuration of the organic EL display panel is not particularly limited, and any known configuration may be used. [Example]

[0098] The present invention will be described in more detail below with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the examples shown below.

[0099] [Example 1] [Preparation of Cellulose Acylate Film (Support)] The following composition was charged into a mixing tank, stirred, and further heated at 90°C for 10 minutes. Thereafter, the obtained composition was filtered through a filter paper having an average pore size of 34 μm and a sintered metal filter having an average pore size of 10 μm to prepare a dope. The solid concentration of the dope was 23.5% by mass, the amount of the plasticizer added was the ratio relative to the cellulose acylate, and the solvent for the dope was methylene chloride / methanol / butanol=81 / 18 / 1 (mass ratio).

[0100] ---------------------------------------------------------------------------------- Cellulose acylate dope (1) ---------------------------------------------------------------------------------- Cellulose acylate (acetyl substitution degree 2.86, viscosity average polymerization degree 310) 100 parts by mass Sugar ester compound 1 (represented by chemical formula (S4)) 6.0 parts by mass Sugar ester compound 2 (represented by chemical formula (S5)) 2.0 parts by mass Silica particle dispersion (AEROSIL R972, manufactured by Nippon Aerosil Co., Ltd.) 0.1 part by mass Solvent (methylene chloride / methanol / butanol) ----------------------------------------------------------------------------------

[0101] [ka] JPEG2025132767000018.jpg5583

[0102] The dope prepared above was cast using a drum film-forming machine. Specifically, the dope was cast from a die onto a metal support cooled to 0°C, and then the resulting web (film) was peeled off. The drum was made of SUS (Steel Special Use Stainless Steel). Next, the web (film) obtained by casting was peeled off from the drum and dried for 20 minutes in a tenter apparatus, which clipped both ends of the web with clips while transporting the film at 30 to 40° C. Subsequently, the web was post-dried by zone heating while being transported with rolls, to produce a cellulose acylate film.

[0103] [Formation of alignment film] On the surface of the cellulose acylate film opposite to the surface that had been in contact with the drum, the following composition 1 for forming an alignment film was continuously applied using a #4 wire bar. The coating was dried with hot air at 140°C for 120 seconds to volatilize the solvent and heat-set the coating, thereby forming an alignment film.

[0104] ---------------------------------------------------------------------------------- Composition for forming alignment film 1 ---------------------------------------------------------------------------------- Multifunctional monomer: aliphatic cyclic tetrafunctional epoxy resin (Epolead GT401, manufactured by Daicel Corporation) 93.11 parts by mass Acrylic polymer: 0.74 parts by mass of Polymer 1-1 below Thermal acid generator: tetrakispentafluorophenylsulfonium borate salt (San-Aid SI-B3A, manufactured by Sanshin Chemical Industry Co., Ltd.) 5.59 parts by mass Hardener: Diisopropylethylamine 0.56 parts by mass Butyl acetate 853.2 parts by mass Methyl ethyl ketone 46.8 parts by mass ----------------------------------------------------------------------------------

[0105] Polymer 1-1 [ka]

[0106] [Formation of Optically Anisotropic Layer] The alignment film prepared above was subjected to a continuous rubbing treatment. At this time, the longitudinal direction of the long film was parallel to the conveying direction, and the angle between the longitudinal direction of the film (conveying direction) and the rotation axis of the rubbing roller was 78°. The longitudinal direction of the film (conveying direction) was set to 90°, and when observed from the film side, the width direction of the film was set as the reference (0°) and clockwise directions were expressed as positive values, so the rotation axis of the rubbing roller was at an angle of 12°. In other words, the position of the rotation axis of the rubbing roller was rotated 78° counterclockwise from the longitudinal direction of the film.

[0107] The rubbed cellulose acylate film was used as a substrate, and an optically anisotropic layer-forming composition (1) containing a rod-shaped liquid crystal compound having the following composition was applied using a Giesser coater to form a composition layer. Next, the obtained composition layer was heated at 95° C. for 60 seconds, which caused the rod-like liquid crystal compound in the composition layer to be aligned in a predetermined direction. Thereafter, the composition layer was irradiated with ultraviolet light (irradiation dose: 25 mJ / cm ) using a 365 nm LED (Light Emitting Diode) lamp (manufactured by Acroedge Co., Ltd.) at 30°C in oxygen-containing air (oxygen concentration: approximately 20% by volume). 2 ). The resulting composition layer was then heated at 95°C for 10 seconds. Thereafter, nitrogen purging was carried out to adjust the oxygen concentration to 100 ppm by volume, and the composition layer was irradiated with ultraviolet light (irradiation dose: 500 mJ / cm ) using a metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at 80°C. 2 ), an optically anisotropic layer in which the alignment state of the liquid crystal compound was fixed was formed. In this way, an optical film (F-1) was produced.

[0108] ---------------------------------------------------------------------------------- Composition for forming optically anisotropic layer (1) ---------------------------------------------------------------------------------- 80 parts by mass of the following rod-shaped liquid crystal compound (A): 17 parts by mass of the following rod-shaped liquid crystal compound (B) 3 parts by mass of the following polymerizable compound (C): Ethylene oxide modified trimethylolpropane triacrylate (V#360, manufactured by Osaka Organic Chemical Co., Ltd.) 4 parts by mass Photopolymerization initiator (Irgacure 819, manufactured by BASF) 3 parts by mass 0.47 parts by mass of the following left-twisted chiral agent (L2) 0.42 parts by mass of the right-twisted chiral agent (R2) shown below 0.08 parts by mass of the following polymer (A) Methyl isobutyl ketone 78 parts by mass Ethyl propionate 78 parts by mass ----------------------------------------------------------------------------------

[0109] Rod-like liquid crystal compound (A) [a mixture of the following liquid crystal compounds (RA), (RB), and (RC) in a mass ratio of 84:14:2] [ka]

[0110] Rod-shaped liquid crystal compound (B) [ka]

[0111] Polymerizable compound (C) (In the following formula, Me represents a methyl group.) [ka]

[0112] Left-twisted chiral agent (L2) [ka]

[0113] Right-twisted chiral agent (R2) [ka]

[0114] Polymer (A) [fluorine part: 39% by mass, mesogen part: 61% by mass, weight average molecular weight: 25,000] [ka]

[0115] The optical film (F-1) prepared above was cut parallel to the rubbing direction, and the optically anisotropic layer was observed from the cross section using a polarizing microscope. The optically anisotropic layer had a thickness of 2.7 μm, and the 1.3 μm thick region (d2) on the substrate side of the optically anisotropic layer (second region) showed homogeneous alignment (horizontal alignment) without a twist angle, while the 1.4 μm thick region (d1) on the air side (opposite the substrate) of the optically anisotropic layer (first region) showed a twisted alignment of the liquid crystal compound. The optical properties of the optical film (F-1) were determined using an Axoscan from Axometrics and its analysis software (Multi-Layer Analysis). The product (Δn2d2) of Δn2 and the thickness d2 at a wavelength of 550 nm in the second region was 177 nm, the twist angle of the liquid crystal compound was 0°, and the alignment axis angle of the liquid crystal compound relative to the longitudinal direction was -11° on the side in contact with the substrate and -11° on the side in contact with the first region. In addition, the product (Δn1d1) of Δn1 and thickness d1 at a wavelength of 550 nm in the first region was 180 nm, the twist angle of the liquid crystal compound was 80°, and the alignment axis angle of the liquid crystal compound relative to the longitudinal direction was -11° on the side in contact with the second region and -91° on the air side.

[0116] [Examples 2 to 28] Optical films (F-2) to (F-28) of Examples 2 to 27 were produced in the same manner as Example 1, except that the components of the composition for forming an alignment film, such as the type and content of the multifunctional monomer, the type, weight-average molecular weight and content of the acrylic polymer, and the presence or absence and content of the monofunctional monomer, were changed to those shown in Table 1 below. In Examples 6 and 23, Celloxide 2021P, which was blended as a polyfunctional monomer, is an aliphatic cyclic bifunctional epoxy resin (manufactured by Daicel Corporation).

[0117] [Example 29] An optical film (F-29) was produced in the same manner as in Example 1, except that the method for forming the alignment film was changed as follows. [Formation of alignment film] On the surface of the cellulose acylate film opposite to the surface that had been in contact with the drum, Composition 29 for forming an alignment film having the following composition was continuously applied using a #4 wire bar. The film was dried with hot air at 100°C for 60 seconds to volatilize the solvent. Thereafter, nitrogen purging was performed to adjust the oxygen concentration to 1%, and the composition layer was irradiated with ultraviolet light (irradiation dose: 100 mJ / cm) using a metal halide lamp (manufactured by Eye Graphics Co., Ltd.) at 25°C. 2 ) and an alignment film was formed.

[0118] ---------------------------------------------------------------------------------- Composition for forming alignment film 29 ---------------------------------------------------------------------------------- Multifunctional monomer: Caprolactone-modified dipentaerythritol Hexaacrylate (DPCA-20, manufactured by Nippon Kayaku Co., Ltd.) 95.97 parts by mass Acrylic polymer: 0.19 parts by mass of the above polymer 1-1 ·Photopolymerization initiator: Omnirad819 (IGM Resins BV) 3.84 parts by mass Butyl acetate 86.3 parts by mass Methyl ethyl ketone 147.0 parts by mass ----------------------------------------------------------------------------------

[0119] [Example 30] An optical film (F-30) of Example 30 was produced in the same manner as in Example 29, except that the type of acrylic polymer in the composition for forming an alignment film was changed to the contents shown in Table 1 below.

[0120] [Comparative Example 1] An acrylic copolymer (A1) (referred to as comparative polymer in Table 1 below) was synthesized with reference to Synthesis Example 1 described in paragraphs

[0069] and

[0070] of JP-A-2022-188610. Next, with reference to Preparation Example 1 described in paragraph

[0093] of the same publication, an alignment film-forming composition H1 was prepared. An optical film (H-1) of Comparative Example 1 was produced in the same manner as in Example 1, except that the composition 1 for forming an alignment film was changed to the composition H1 for forming an alignment film.

[0121] [Comparative Examples 2 to 6] Optical films (H-2) to (H-6) of Comparative Examples 2 to 6 were produced in the same manner as in Example 1, except that the components of the composition for forming an alignment film, such as the presence or absence and content of a polyfunctional monomer, the presence or absence, type and content of an acrylic polymer, and the presence or absence and content of a monofunctional monomer, were changed to those shown in Table 1 below.

[0122] [evaluation] The prepared optical films and the alignment films during preparation were evaluated as follows, and the results are shown in Table 1 below.

[0123] [Orientation] The optically anisotropic layer in the prepared optical film was observed at random in 10 fields (field size 1715×1280 μm) at a magnification of 50 times using a polarizing microscope in a crossed Nicol state, and each field was classified into the following three categories. I: No optical defects observed. II: Slight optical defects are observed, but at a level that does not pose a problem in practical use. III: Many optical defects are observed, and the level is problematic for practical use. The ten visual fields were evaluated according to the following criteria: A rating of C or higher can be evaluated as an alignment film having high alignment properties. <Standards> AA: All 10 fields of view are I. A: All 10 fields are I or II, with 1 to 2 II fields. B: All 10 fields are I or II, with 3 to 5 II fields. C: All 10 fields are I or II, with 6 to 10 II fields. D: 10 fields contain III, and the number of III fields is 1 to 5. E: 10 fields contained III, and the number of III fields was 6–10.

[0124] [Dust generation] In Examples 1 to 30 and Comparative Examples 1 to 6, when an alignment film was formed by rubbing, the number of floating particles having a particle size of 0.3 μm or more was measured using a particle counter HANDHELD3016 manufactured by Lighthouse Corp. The measurement was performed at the position indicated by the symbol A in Figure 4 of JP 2013-205453 A (an explanatory diagram showing the installation location of the particle counter). The relative ratio was calculated when the number in Comparative Example 1 was taken as 100, and the results were evaluated on a 6-point scale according to the following criteria. Note that a rating of C or higher can be evaluated as suppressing dust generation. <Standards> AA: Ratio less than 1.0 A: The ratio is greater than or equal to 1.0 and less than 5.0 B: Ratio is 5.0 or more and less than 20.0 C: Ratio is greater than or equal to 20.0 and less than 50.0 D: Ratio is 50.0 or more and less than 80.0 E: Ratio is 80.0 or more

[0125] [Adhesion] A cross-cut 100-square test was carried out on the optically anisotropic layers of the optical films produced in Examples 1, 4, 14, 18, 21, 22, 29, and 30. The adhesive tape used in the peel test was Cellotape (registered trademark), and the peel test was carried out three times. After the peel test, the number of squares from which half or more of the area had peeled was counted and evaluated according to the following criteria. A rating of B or higher was considered to indicate excellent adhesion. <Standards> A: 0 to 20 squares peeled off B: 20 ​​to 50 squares peeled off C: 50 or more squares have been removed

[0126] [Table 1]

[0127] The structures of the acrylic polymers in Table 1 are shown below. The comparative polymer used in Comparative Example 1 is, as described above, an acrylic copolymer (A1) with reference to Synthesis Example 1 described in paragraphs

[0069] and

[0070] of JP-A-2022-188610.

[0128] Polymer 1-1 (homopolymer) [ka]

[0129] Polymer 1-2 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0130] Polymer 1-3 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0131] Polymer 1-4 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0132] Polymer 1-5 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0133] Polymer 1-6 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0134] Polymer 2-1 (homopolymer) [ka]

[0135] Polymer 2-2 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0136] Polymer 2-3 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0137] Polymer 2-4 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0138] Polymer 2-5 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0139] Polymer 2-6 (The numbers in the following formula indicate the content (% by mass) of each repeating unit relative to the total repeating units in the polymer.) [ka]

[0140] From the results shown in Table 1, it was found that when the acrylic polymer described in JP 2022-188610 A (i.e., the above-mentioned Patent Document 1) was blended in the preparation of the alignment film, the alignment of the liquid crystal compound in the optically anisotropic layer was good, but dust generation could not be suppressed (Comparative Example 1). Furthermore, when no polyfunctional monomer was added to prepare the alignment film, the alignment of the liquid crystal compound in the optically anisotropic layer was good, but it was found that dust generation could not be suppressed (Comparative Example 2). Furthermore, when the amount of polyfunctional monomer blended was less than 30% by mass relative to the total mass of the solid content of the composition, the alignment of the liquid crystal compound in the optically anisotropic layer was good, but it was found that dust generation could not be suppressed (Comparative Examples 3 and 4). Furthermore, when no acrylic polymer was blended, dust generation could be suppressed, but it was found that the alignment of the liquid crystal compound in the optically anisotropic layer was poor (Comparative Example 5). Furthermore, when the amount of acrylic polymer blended was more than 10.0% by mass relative to the total mass of the solid content of the composition, the alignment of the liquid crystal compound in the optically anisotropic layer was good, but it was found that dust generation could not be suppressed (Comparative Example 6).

[0141] In contrast, it was found that an alignment film prepared using a cured product of a composition in which a polyfunctional monomer and an acrylic polymer satisfying the above-mentioned condition 1 or 2 were blended in specific amounts exhibited good alignment of the liquid crystal compound in the optically anisotropic layer and suppressed dust generation (Examples 1 to 30). In particular, a comparison between Example 4 and Example 6 revealed that dust generation can be further suppressed when the polyfunctional monomer has three or more polymerizable groups. Furthermore, a comparison between Example 1 and Example 4 revealed that when the acrylic polymer has a polymerizable group, dust generation is further suppressed and adhesion to the cured liquid crystal layer is also improved. Furthermore, comparison between Example 4 and Example 7, and comparison between Examples 15 to 19, revealed that when the acrylic polymer contains a fluorine atom or a silicon atom, the alignment of the liquid crystal compound in the optically anisotropic layer becomes better. Furthermore, the results of Examples 3 to 5 show that the alignment of the liquid crystal compound in the optically anisotropic layer is improved when the weight-average molecular weight of the acrylic polymer satisfying Condition 1 is 30,000 or more. Similarly, the results of Examples 17 to 19 show that the alignment of the liquid crystal compound in the optically anisotropic layer is improved when the weight-average molecular weight of the acrylic polymer satisfying Condition 2 is 10,000 or more.

Claims

1. An alignment film made using a cured product of a composition containing a polyfunctional monomer and an acrylic polymer, the content of the polyfunctional monomer is 30% by mass or more based on the total mass of the solid content of the composition, the content of the acrylic polymer is 0.01 to 10.0% by mass based on the total mass of the solid content of the composition, The acrylic polymer satisfies either of the following conditions 1 and 2: Condition 1: No aromatic ring. Condition 2: The compound has a mesogen group represented by the following formula (M). 【Chemical 1】 Here, in the formula (M), * indicates the bond position. n represents an integer of 2 or more. Ph １１ and Ph １２ each independently represents an aromatic ring, and a plurality of Ph １１ may be the same or different. L １１ represents a single bond or a divalent linking group, and a plurality of L １１ may be the same or different.

2. 2. The alignment film according to claim 1, wherein the polyfunctional monomer is a monomer having three or more polymerizable groups.

3. 3. The alignment film according to claim 2, wherein the polymerizable group is any one of an epoxy group, an acryloyl group, and a methacryloyl group.

4. The alignment film according to claim 1 , wherein the acrylic polymer has a polymerizable group.

5. The alignment film according to claim 1 , wherein the acrylic polymer contains a fluorine atom or a silicon atom.

6. 2. The alignment film according to claim 1, wherein the weight average molecular weight of the acrylic polymer is 30,000 or more when the acrylic polymer satisfies the condition 1, and 10,000 or more when the acrylic polymer satisfies the condition 2.

7. An optical film having an alignment film and a liquid crystal cured layer, The alignment film is the alignment film according to any one of claims 1 to 6, The optical film, wherein the liquid crystal cured layer is a layer in which the alignment state of a liquid crystal compound is fixed.

8. the liquid crystal cured layer is an optically anisotropic layer, The optical film according to claim 7 , wherein the optically anisotropic layer has a λ / 4 function.

9. An image display device comprising the optical film according to claim 7 .

10. 10. The image display device according to claim 9, which is a liquid crystal display device.

11. The image display device according to claim 9, which is an organic EL display device.

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