Optical film, polarizing plate, composition for alignment film formation, and method for producing polarizing plate

Abstract

The present invention addresses the problem of providing an optical film demonstrating excellent UV absorbency, excellent alignment of liquid crystal compounds in an optical anisotropic layer, and excellent adherence with an alignment membrane and the optical anisotropic layer. This optical film comprises an alignment membrane and an optical anisotropic layer disposed adjacent to the alignment membrane. The optical anisotropic layer is formed using a composition containing a liquid crystal compound. The alignment membrane contains UV-absorber-containing particles and a cured product of a polymerizable compound having a polymerizable group. The average particle diameter of the particles is 500 nm or less and the maximum absorption wavelength of the UV absorber is within a range from 320 to 400 nm.

Description

Optical film, polarizing plate, composition for forming alignment film, and method for manufacturing polarizing plate

[0001] The present invention relates to an optical film, a polarizing plate, a composition for forming an alignment film, and a method for producing a polarizing plate.

[0002] Optically anisotropic layers are used in a variety of applications. Specific applications of optically anisotropic layers include widening the viewing angle in image display devices and suppressing coloration. For example, a layer formed using a liquid crystal compound has been proposed as an optically anisotropic layer.

[0003] Furthermore, in image display devices, a layer containing an ultraviolet absorber may be provided in order to improve the durability of an optical laminate (optical film) containing an optically anisotropic layer. For example, Patent Document 1 discloses an optical laminate (optical film) having a positive A layer and an ultraviolet absorbing layer in contact with the positive A layer. It also discloses that the ultraviolet absorbing layer is an alignment film and that the positive A layer contains a liquid crystal compound.

[0004] Japanese Patent Application Laid-Open No. 2021-189224

[0005] Patent Document 1 describes an embodiment in which a molecular ultraviolet absorber is used as the ultraviolet absorber contained in the ultraviolet absorbing layer. The present inventors formed an alignment film containing an ultraviolet absorber with reference to the technology described in Patent Document 1, and then formed an optically anisotropic layer containing a liquid crystal compound on the alignment film. However, they found that the adhesion between the alignment film and the optically anisotropic layer was sometimes insufficient. Furthermore, in the optically anisotropic layer formed on the alignment film, high alignment of the liquid crystal compound contained in the optically anisotropic layer is also required.

[0006] Therefore, an object of the present invention is to provide an optical film that has excellent ultraviolet absorption properties, excellent alignment of a liquid crystal compound in an optically anisotropic layer, and excellent adhesion between an alignment film and an optically anisotropic layer. Another object of the present invention is to provide a polarizing plate including the optical film, a composition for forming an alignment film, and a method for producing a polarizing plate.

[0007] As a result of intensive research aimed at solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved when particles containing a specific ultraviolet absorber have a particle size equal to or smaller than a specific size, and have thus completed the present invention. That is, it has been found that the above-mentioned problems can be solved by the following configuration.

[0008] [1] An optical film comprising an alignment film and an optically anisotropic layer disposed adjacent to the alignment film, wherein the optically anisotropic layer is formed using a composition containing a liquid crystal compound, the alignment film comprises particles containing an ultraviolet absorber and a cured product of a polymerizable compound having a polymerizable group, the particles having an average particle size of 500 nm or less, and the ultraviolet absorber having a maximum absorption wavelength in the range of 320 to 400 nm. [2] The optical film according to [1], wherein the maximum absorption wavelength is in the range of 360 to 400 nm. [3] The optical film according to [1] or [2], wherein the liquid crystal compound has a polymerizable group, and wherein the polymerizable group of the liquid crystal compound and the polymerizable group of the polymerizable compound are both radically polymerizable groups, or the polymerizable group of the liquid crystal compound and the polymerizable group of the polymerizable compound are both cationically polymerizable groups. [4] The optical film according to any one of [1] to [3], wherein the particles have polymerizable groups, and the polymerizable groups of the particles and the polymerizable group of the polymerizable compound are both radically polymerizable groups, or the polymerizable groups of the particles and the polymerizable group of the polymerizable compound are both cationically polymerizable groups. [5] A polarizing plate comprising the optical film according to any one of [1] to [4], and a polarizer. [6] A composition for forming an alignment film, comprising particles containing an ultraviolet absorber and a polymerizable compound having a polymerizable group, wherein the particles have an average particle size of 500 nm or less, and the ultraviolet absorber has a maximum absorption wavelength in the range of 320 to 400 nm. [7] The composition for forming an alignment film according to [6], wherein the maximum absorption wavelength is in the range of 360 to 400 nm. [8] The composition for forming an alignment film according to [6] or [7], wherein the particles have polymerizable groups, and the polymerizable groups of the particles and the polymerizable groups of the polymerizable compound are both radical polymerizable groups, or the polymerizable groups of the particles and the polymerizable groups of the polymerizable compound are both cationically polymerizable groups.[9] A method for producing a polarizing plate, comprising the steps of: applying the composition for forming an alignment film according to any one of [6] to [8] onto a support to form a first coating film, and performing an alignment treatment on the first coating film; applying a composition containing a liquid crystal compound onto the first coating film that has been subjected to the alignment treatment to form a second coating film; performing a curing treatment on the first coating film and the second coating film to form an alignment film and an optically anisotropic layer, thereby forming a laminate including the support, the alignment film, and the optically anisotropic layer; and bonding the laminate and the polarizer so that the optically anisotropic layer and the polarizer face each other, and peeling the support from the resulting bonded product to obtain a polarizing plate including the polarizer, the optically anisotropic layer, and the alignment film.

[0009] According to the present invention, an optical film having excellent ultraviolet absorption properties, excellent alignment of a liquid crystal compound in an optically anisotropic layer, and excellent adhesion between an alignment film and an optically anisotropic layer can be provided. The present invention also provides a polarizing plate including the optical film, a composition for forming an alignment film, and a method for producing a polarizing plate.

[0010] The present invention will be described in detail below. The following description of the components may be based on representative embodiments of the present invention, but the present invention is not limited to such embodiments.

[0011] The meaning of each description in this specification is as follows: 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.

[0012] In this specification, Re(λ) and Rth(λ) represent the in-plane retardation and the thickness direction retardation, respectively, at a wavelength λ. Unless otherwise specified, the wavelength λ is 550 nm. In this specification, Re(λ) and Rth(λ) are values ​​measured at a wavelength λ using an AxoScan manufactured by Axometrics. By inputting the average refractive index ((nx + ny + nz) / 3) and film thickness (d (μm)) into AxoScan, the following slow axis direction (°) is calculated: Re(λ) = R0(λ) Rth(λ) = ((nx + ny) / 2 - nz) × d. Note that R0(λ) is displayed as a numerical value calculated by AxoScan, but it means Re(λ).

[0013] In this specification, the refractive indices nx, ny, and nz are measured using an Abbe refractometer (NAR-4T, manufactured by Atago Co., Ltd.) with a sodium lamp (λ = 589 nm) as a light source. When measuring wavelength dependency, measurements can be made using a multi-wavelength Abbe refractometer DR-M2 (manufactured by Atago Co., Ltd.) in combination with an interference filter. Values ​​from the Polymer Handbook (John Wiley & Sons, Inc.) and catalogs of various optical films can also be used. Examples of average refractive index values ​​for major optical films are listed below: cellulose acylate (1.48), cycloolefin polymer (1.52), polycarbonate (1.59), polymethyl methacrylate (1.49), and polystyrene (1.59).

[0014] In addition, the bonding direction of the divalent group (for example, —O—CO—) described in this specification is not particularly limited. １ -L ２ -L ３ In the bond ２ When is —O—CO—, L １ The position where it is bonded to the side is *1, L ３ If the position bonded to the side is *2, then L ２may be *1-O-CO-*2 or *1-CO-O-*2. In this specification, "(meth)acrylate" is a notation representing "acrylate" or "methacrylate", "(meth)acrylic" is a notation representing "acrylic" or "methacrylic", and "(meth)acryloyl" is a notation representing "acryloyl" or "methacryloyl".

[0015] <Optical Film> The optical film of the present invention includes an alignment film and an optically anisotropic layer disposed adjacent to the alignment film. The optical film of the present invention is characterized in that the alignment film contains particles containing an ultraviolet absorber and a cured product of a polymerizable compound having a polymerizable group, the particles having an average particle size of 500 nm or less, and the ultraviolet absorber having a maximum absorption wavelength in the range of 320 to 400 nm.

[0016] Although the detailed mechanisms by which the optical film of the present invention exhibits excellent UV absorption properties, excellent alignment of the liquid crystal compound in the optically anisotropic layer, and excellent adhesion between the alignment film and the optically anisotropic layer are not entirely clear, the inventors speculate as follows. The optical film of the present invention exhibits excellent UV absorption properties because it contains a UV absorber whose maximum absorption wavelength is in the range of 320 to 400 nm. Meanwhile, polymerization of a polymerizable compound contained in an alignment film is generally promoted by UV light. Therefore, if the alignment film contains a UV absorber, polymerization of the polymerizable compound contained in the alignment film may be inhibited. It is believed that if UV absorber molecules are uniformly dispersed in the alignment film, polymerization of the polymerizable compound may be inhibited uniformly throughout the alignment film. Here, in the present invention, since the UV absorber is contained in particles, it can be said that the initiation of polymerization of the polymerizable compound in areas where the UV absorber is not present in the vicinity is less likely to be inhibited. This is believed to result in polymerization of the polymerizable compound proceeding in the alignment film, resulting in excellent adhesion between the alignment film and the optically anisotropic layer. The particles contained in the alignment film may also be present between the alignment film and a layer of a composition containing a liquid crystal compound formed on the alignment film. Since particles do not usually have the ability to align liquid crystal compounds, it is thought that the regions where the particles exist at the interface may become alignment defects of the liquid crystal compounds. Here, in the present invention, since the average particle diameter of the particles contained in the alignment film is 500 nm or less, the regions where alignment defects occur are small, and as a result, it is thought that the alignment of the liquid crystal compounds in the optically anisotropic layer is excellent.

[0017] The components included in the optical film will be described below.

[0018] [Alignment Film] The alignment film contained in the optical film of the present invention contains particles containing an ultraviolet absorber and a cured product of a polymerizable compound having a polymerizable group. There are no particular limitations on the method for obtaining the alignment film contained in the optical film, but a method of applying an alignment film-forming composition (described later) to a support, and performing an alignment treatment and a curing treatment to obtain the alignment film is preferred. Therefore, the alignment film may contain components contained in the alignment film-forming composition (described later) and components derived from the components contained in the alignment film-forming composition. Components other than the particles containing an ultraviolet absorber and the cured product of the polymerizable compound having a polymerizable group will be described later. The alignment film may also be a photo-alignment film that exhibits the ability to align liquid crystal compounds upon light irradiation. The alignment film will be described below.

[0019] (Particles) The particles contain an ultraviolet absorber. The particles may contain an ultraviolet absorber, and may also contain components other than the ultraviolet absorber. Furthermore, the particles may consist solely of a polymeric ultraviolet absorber. In this specification, "particles containing an ultraviolet absorber" may refer to an embodiment in which the particles contain a low-molecular-weight ultraviolet absorber or a polymeric ultraviolet absorber. A low-molecular-weight ultraviolet absorber is a compound that has ultraviolet absorption ability but does not have a repeating unit. A polymeric ultraviolet absorber is a polymer compound that has a repeating unit containing a structure with ultraviolet absorption ability. Furthermore, the state of the ultraviolet absorber contained in the particles is not particularly limited. The ultraviolet absorber may be contained uniformly throughout the particles, or may be contained in a state in which the ultraviolet absorber is concentrated in a portion of the particles. When the ultraviolet absorber is contained in a state in which the ultraviolet absorber is concentrated in a portion of the particles, there may be many portions in the particles where the ultraviolet absorber is concentrated, or there may be only one portion where the ultraviolet absorber is concentrated (e.g., a core-shell structure). The particles also preferably have a polymerizable group, and more preferably have a polymerizable group on the surface of the particles. Examples of the polymerizable group include a radically polymerizable group and a cationically polymerizable group. Details of the components contained in the particles will be described later in the section on the composition for forming an alignment film.

[0020] The particles have an average particle size of 500 nm or less. The average particle size of the particles is preferably 20 to 500 nm, more preferably 30 to 450 nm, and even more preferably 50 to 300 nm. The average particle size of the particles is obtained by preparing a cross section of the optical film and averaging the equivalent circle diameters of the cross sections of the particles on the surface of the cross section of the alignment film. Specifically, the optical film is first embedded in an epoxy resin. The embedded optical film is cut with an ultramicrotome to obtain a sliced ​​sample of the optical film for observation. If necessary, the surface of the obtained sample for observation is subjected to a carbon vapor deposition treatment to ensure surface conductivity. The obtained slice-like sample is then attached to a wire grid, and the sample is observed using a transmission electron microscope (TEM) or a scanning transmission electron microscope (STEM). As the TEM or STEM device, for example, the "JEM-F200" manufactured by JEOL Ltd. can be used. The magnification is changed appropriately depending on the object of observation, and observation is performed at multiple locations while changing the observation area. In the obtained TEM or STEM image, the circle-equivalent diameter of the particle cross section is measured. Measurements are continued until 100 particle cross sections are measured, and the arithmetic mean is taken as the average particle diameter of the particles. Note that if the number of particle cross sections included in one TEM or STEM image is less than the above number, measurements are continued in other TEM or STEM images until the above number is reached. Furthermore, when the image of the particles is unclear in the TEM image or STEM image (for example, when the difference in electron beam transmittance between the cured product of the polymerizable compound of the alignment film and the particles is small), elemental mapping may be performed using an energy dispersive X-ray spectrometer attached to the TEM or STEM device, and the particle size may be measured by comparing it with the TEM or STEM image.

[0021] The maximum absorption wavelength of the ultraviolet absorber contained in the particles is located in the range of 320 to 400 nm. The maximum absorption wavelength of the ultraviolet absorber contained in the particles is preferably located in the range of 360 to 400 nm. The maximum absorption wavelength of the ultraviolet absorber contained in the particles can be measured using a spectrophotometer. More specifically, the alignment film is separated from the optically anisotropic layer, and the absorption spectrum of the alignment film is obtained using the spectrophotometer. Note that the absorption spectrum of a layer other than the alignment film contained in the optical film may be measured in advance and compared with the absorption spectrum of the entire optical film to obtain the maximum absorption wavelength of the ultraviolet absorber contained in the particles.

[0022] The content of particles in the alignment film can be adjusted appropriately depending on the particles used, but from the viewpoint of maintaining good alignment, it is preferably 0.1 to 30 mass %, more preferably 0.5 to 25 mass %, even more preferably 1 to 20 mass %, particularly preferably 1 to 10 mass %, and most preferably 1 to 5 mass %, relative to the total mass of the alignment film.

[0023] (Cured Product of Polymerizable Compound) A cured product of a polymerizable compound is obtained by curing the polymerizable compound. The polymerizable compound is a compound having a polymerizable group. Examples of the polymerizable group that the polymerizable compound has include a radical polymerizable group, a cationically polymerizable group, and an anionically polymerizable group, and a radical polymerizable group or a cationically polymerizable group is preferred. The polymerizable compound may have multiple types of polymerizable groups. For example, the polymerizable compound may be a compound having a radical polymerizable group and a cationically polymerizable group.

[0024] When the particles have a polymerizable group, it is also preferable that the polymerizable group of the particles and the polymerizable group of the polymerizable compound are both radical polymerizable groups, or that the polymerizable group of the particles and the polymerizable group of the polymerizable compound are both cationic polymerizable groups. When the above requirements are satisfied, the adhesion between the alignment film and the optically anisotropic layer is more excellent. Details of the polymerizable compound will be described in detail later in the section on the composition for forming an alignment film.

[0025] The content of the cured polymerizable compound in the alignment film is preferably 50 to 99.9 mass%, more preferably 60 to 99 mass%, even more preferably 70 to 99 mass%, particularly preferably 80 to 99 mass%, and most preferably 85 to 99 mass%, based on the total mass of the alignment film.

[0026] The thickness of the alignment film is preferably from 0.01 to 10 μm, more preferably from 0.01 to 5 μm, and even more preferably from 0.01 to 1 μm.

[0027] [Optically Anisotropic Layer] The optically anisotropic layer is a layer formed using a composition containing a liquid crystal compound. The optically anisotropic layer is preferably a layer formed by fixing the alignment state of the liquid crystal compound. In a layer in which the alignment state of the liquid crystal compound is fixed, optical properties derived from the liquid crystal compound are exhibited, and these optical properties vary depending on the liquid crystal compound and the alignment direction and alignment state of the liquid crystal compound. In a layer in which the alignment state of the liquid crystal compound is fixed, it is sufficient that the alignment state of the liquid crystal compound is fixed, and the liquid crystal compound may no longer have liquid crystallinity.

[0028] The orientation state of the liquid crystal compound in the optically anisotropic layer can be appropriately selected depending on the application of the optical film. Examples of the orientation state of the liquid crystal compound include nematic orientation (an orientation state similar to that in a nematic phase), smectic orientation (an orientation state similar to that in a smectic phase), and cholesteric orientation (an orientation state similar to that in a cholesteric phase). The orientation direction of the liquid crystal compound may be parallel to the in-plane direction of the optically anisotropic layer (homogeneous orientation) or perpendicular to the in-plane direction of the optically anisotropic layer (homeotropic orientation). The orientation direction may also be tilted from the direction parallel to or perpendicular to the in-plane direction of the optically anisotropic layer. The orientation direction of the liquid crystal compound may also vary across the thickness of the optically anisotropic layer. For example, when the liquid crystal compound is cholesterically oriented, the pitch of the cholesteric phase may vary across the thickness of the optically anisotropic layer. Such an optically anisotropic layer is also called a pitch gradient layer. When the liquid crystal compound is homogeneously aligned, the alignment direction on one surface of the optically anisotropic layer may be inclined from the horizontal to the in-plane direction of the optically anisotropic layer.

[0029] The optically anisotropic layer is formed by fixing the aligned state of the liquid crystal compound. Here, the "fixed" state refers to a state in which the aligned liquid crystal compound is maintained. For example, a state in which there is no fluidity and the fixed alignment state can be stably maintained without causing changes in the alignment form due to external fields or external forces within a temperature range of 0 to 50°C, or even under more severe conditions, within a temperature range of -30 to 70°C. Examples of such fixation methods include, as described in detail below, a method in which a polymerizable liquid crystal compound is oriented to form an aligned state, and then a curing treatment is performed to react the polymerizable groups, thereby fixing the aligned state of the liquid crystal compound.

[0030] The thickness of the optically anisotropic layer is not particularly limited, but is preferably 0.5 to 10 μm. Below, the components contained in the composition containing a liquid crystal compound (hereinafter also referred to as "liquid crystal composition") will be explained.

[0031] (Liquid Crystal Compound) The type of liquid crystal compound contained in the liquid crystal composition is not particularly limited. Generally, liquid crystal compounds can be classified into rod-shaped types (rod-shaped liquid crystal compounds) and discotic types (discotic liquid crystal compounds) based on their shape. Liquid crystal compounds can also be classified into low-molecular-weight types and polymer types. Polymers generally refer to compounds with a degree of polymerization of 100 or more (Masao Doi, Polymer Physics / Phase Transition Dynamics, p. 2, Iwanami Shoten, 1992). In the present invention, any liquid crystal compound can be used, but rod-shaped or discotic liquid crystal compounds are preferred, and rod-shaped liquid crystal compounds are more preferred. Two or more rod-shaped liquid crystal compounds, two or more discotic liquid crystal compounds, or a mixture of a rod-shaped liquid crystal compound and a discotic liquid crystal compound may also be used.

[0032] The liquid crystal compound may be a polymerizable liquid crystal compound having a polymerizable group. That is, for example, it may be a polymerizable rod-shaped liquid crystal compound or a polymerizable discotic liquid crystal compound. The type of polymerizable group possessed by the liquid crystal compound is not particularly limited, and a radically polymerizable group or a cationically polymerizable group is preferred, a polymerizable ethylenically unsaturated group or a ring-polymerizable group is more preferred, and a (meth)acryloyl group, a vinyl group, a styryl group, an allyl group, or an epoxy group is even more preferred. Examples of rod-shaped liquid crystal compounds include the liquid crystal compounds described in claim 1 of JP-A-11-513019 and paragraphs

[0026] to

[0098] of JP-A-2005-289980. Examples of discotic liquid crystal compounds include the liquid crystal compounds described in paragraphs

[0020] to

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

[0013] to

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

[0033] The content of the liquid crystal compound in the liquid crystal composition is not particularly limited, but is preferably 50% by mass or more, more preferably 70% by mass or more, based on the total mass of all solids in the liquid crystal composition. The upper limit is not particularly limited, but is often 95% by mass or less. The solid content refers to components that can form a cured product after removing the solvent, and is considered to be solid even if the component is in a liquid state.

[0034] (Other Polymerizable Compounds) The liquid crystal composition may contain other polymerizable compounds having one or more polymerizable groups. Here, the polymerizable group of the other polymerizable compounds is not particularly limited, and examples thereof include an acryloyl group, a methacryloyl group, a vinyl group, a styryl group, and an allyl group. Among these, it is preferable that the other polymerizable compounds have an acryloyl group or a methacryloyl group.

[0035] Other polymerizable compounds include non-liquid crystal polymerizable compounds. Specific examples include esters of polyhydric alcohols and (meth)acrylic acid (e.g., ethylene glycol di(meth)acrylate, 1,4-cyclohexane diacrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,2,3-cyclohexane tetramethacrylate, polyurethane polyacrylate, and polyester polyacrylate), vinylbenzene and derivatives thereof, vinyl sulfone, acrylamide, and methacrylamide.

[0036] When such other polymerizable compounds are contained, the content thereof is preferably less than 50% by mass, more preferably 40% by mass or less, and still more preferably 2 to 30% by mass, relative to the mass of the liquid crystal compound (total mass of the liquid crystal compounds when a plurality of liquid crystal compounds are present).

[0037] (Chiral Dopant) The liquid crystal composition may contain a chiral dopant. When the liquid crystal composition contains a chiral dopant, the liquid crystal compound can be twisted and aligned along the helical axis. This alignment state is also called cholesteric alignment. The type of chiral dopant is not particularly limited. Any of the known chiral dopants (for example, those described in "Liquid Crystal Device Handbook," edited by the 142nd Committee of the Japan Society for the Promotion of Science, Chapter 3, Section 4-3, "Chiral Dopants for TN and STN," page 199, 1989) can be used.

[0038] The chiral agent may be a photosensitive chiral agent (hereinafter simply referred to as "chiral agent A") whose helical twisting force changes upon irradiation with light. Chiral agent A may be liquid crystalline or non-liquid crystalline. Chiral agent A generally contains an asymmetric carbon atom. Note that chiral agent A may be an axially asymmetric compound or a planar asymmetric compound that does not contain an asymmetric carbon atom. Chiral agent A may have a polymerizable group.

[0039] The chiral agent A may be a chiral agent whose helical twisting power increases or decreases upon light irradiation. Among these, a chiral agent whose helical twisting power decreases upon light irradiation is preferred. In this specification, "increase and decrease in helical twisting power" refers to an increase or decrease when the initial helical direction of the chiral agent A (before light irradiation) is defined as "positive." Therefore, even when the helical twisting power continues to decrease upon light irradiation and exceeds 0, the helical direction becomes "negative" (i.e., when a helical twist is induced in the opposite helical direction to the initial helical direction (before light irradiation)), this also falls under the category of a "chiral agent whose helical twisting power decreases."

[0040] Examples of chiral agents A include so-called photoreactive chiral agents. Photoreactive chiral agents have a chiral moiety and a photoreactive moiety that undergoes structural changes upon light irradiation, and are compounds that, for example, significantly change the twisting power of a liquid crystal compound depending on the amount of irradiation. Among these, chiral agents A are preferably compounds having at least a photoisomerizable moiety, and it is more preferable that the photoisomerizable moiety has a photoisomerizable double bond. When the chiral agent has a photoisomerizable group, this is preferred because a pattern with a desired reflection wavelength corresponding to the emission wavelength can be formed by irradiating a photomask with actinic rays or the like after coating and orientation. Preferred photoisomerizable groups are isomerizable moieties of compounds that exhibit photochromic properties, azobenzene moieties, cinnamoyl moieties, α-cyanocinnamoyl moieties, stilbene moieties, and chalcone moieties. Specific compounds that can be used include those described in JP-A-2002-080478, JP-A-2002-080851, JP-A-2002-179668, JP-A-2002-179669, JP-A-2002-179670, JP-A-2002-179681, JP-A-2002-179682, JP-A-2002-338575, JP-A-2002-338668, JP-A-2003-313189, and JP-A-2003-313292.

[0041] The liquid crystal composition may contain two or more types of chiral dopants A, or may contain at least one type of chiral dopants A and at least one type of chiral dopants whose helical twisting power does not change upon irradiation with light.

[0042] The content of the chiral dopant A in the liquid crystal composition is not particularly limited, but is preferably 5.0% by mass or less, more preferably 3.0% by mass or less, and even more preferably 2.0% by mass or less, relative to the total mass of the liquid crystal compound, in order to facilitate uniform alignment of the liquid crystal compound. The lower limit of the content of the chiral dopant A is not particularly limited, but is preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and even more preferably 0.05% by mass or more, relative to the total mass of the liquid crystal compound.

[0043] (Polymerization Initiator) The liquid crystal composition may contain a polymerization initiator. The polymerization reaction initiated by the polymerization initiator may be a thermal polymerization reaction using a thermal polymerization initiator or a photopolymerization reaction using a photopolymerization initiator, with a photopolymerization reaction being more preferred. Examples of the photopolymerization initiator include α-carbonyl compounds (described in U.S. Patent Nos. 2,367,661 and 2,367,670), acyloin ethers (described in U.S. Patent No. 2,448,828), α-hydrocarbon-substituted aromatic acyloin compounds (described in U.S. Patent No. 2,722,512), polynuclear quinone compounds (described in U.S. Patent Nos. 3,046,127 and 2,951,758), a combination of triarylimidazole dimer and p-aminophenyl ketone (described in U.S. Patent No. 3,549,367), acrylic esters (described in U.S. Patent Nos. 2,448,828), α-hydrocarbon-substituted aromatic acyloin compounds (described in U.S. Patent Nos. 2,722,512), polynuclear quinone compounds (described in U.S. Patents Nos. 3,046,127 and 2,951,758), a combination of triarylimidazole dimer and p-aminophenyl ketone (described in U.S. Patent No. 3,549,367), and the like. Examples of suitable oxime ester compounds include azine and phenazine compounds (described in JP-A-60-105667 and U.S. Pat. No. 4,239,850), oxadiazole compounds (described in U.S. Pat. No. 4,212,970), acylphosphine oxide compounds (described in JP-B-63-040799, JP-B-5-029234, JP-A-10-095788, and JP-A-10-029997), and oxime ester compounds (e.g., OXE-01 and OXE-02 manufactured by Omni Corporation, and NCI-1919 manufactured by Adeka Corporation).

[0044] When the liquid crystal composition contains a polymerization initiator, the content of the polymerization initiator is preferably 0.01 to 20% by mass, more preferably 0.4 to 8% by mass, based on the total mass of the solid content of the liquid crystal composition.

[0045] (Solvent) The liquid crystal composition may contain a solvent. As the solvent, an organic solvent is preferably used. Examples of the organic solvent include amides (e.g., N,N-dimethylformamide, etc.), sulfoxides (e.g., dimethyl sulfoxide, etc.), hydrocarbons (e.g., toluene, hexane, etc.), alkyl halides (e.g., chloroform, dichloromethane, etc.), esters (e.g., methyl acetate, butyl acetate, ethyl propionate, etc.), ketones (e.g., acetone, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone, cyclopentanone, etc.), and ethers (e.g., tetrahydrofuran, 1,2-dimethoxyethane, etc.). Of these organic solvents, esters and ketones are preferred. One type of solvent may be used alone, or two or more types may be used in combination.

[0046] (Other Components) The liquid crystal composition may contain components other than the above-mentioned components, such as a liquid crystal alignment control agent, an acid generator, a surfactant, a tilt angle control agent, an alignment film interface alignment agent, a plasticizer, and a crosslinking agent.

[0047] [Other Components] The optical film of the present invention may include other components. Examples of other components include a support. Details of the support will be described later. When the optical film further includes a support, the support is preferably provided on the alignment layer side of the optical film.

[0048] <Composition for forming an alignment film> The composition for forming an alignment film of the present invention contains particles containing an ultraviolet absorber and a polymerizable compound having a polymerizable group, the particles having an average particle size of 500 nm or less, and the maximum absorption wavelength of the ultraviolet absorber being in the range of 320 to 400 nm. The above-mentioned alignment film can be formed by applying the composition for forming an alignment film to a support, and then performing an alignment treatment and a curing treatment. The components contained in the composition for forming an alignment film will be described below.

[0049] [Particles] The particles contained in the composition for forming an alignment film of the present invention contain an ultraviolet absorber, and have an average particle size of 500 nm or less. The maximum absorption wavelength of the ultraviolet absorber is located in the range of 320 to 400 nm.

[0050] The average particle size of the particles is measured according to the method described above. Specifically, in the procedure described above, a film including at least an alignment film formed from a composition for forming an alignment film is used instead of the optical film, and the average particle size is measured. The preferred embodiment of the average particle size of the particles is the same as the preferred embodiment of the average particle size of the particles described above.

[0051] The maximum absorption wavelength of the ultraviolet absorber contained in the particles is located in the range of 320 to 400 nm. The maximum absorption wavelength of the ultraviolet absorber contained in the particles is preferably located in the range of 360 to 400 nm. The maximum absorption wavelength of the ultraviolet absorber contained in the particles is measured in accordance with the method described above. More specifically, in the above-described procedure, an alignment film formed from the alignment film-forming composition is used, and the absorption spectrum of the alignment film is obtained with a spectrophotometer. The maximum absorption wavelength of the ultraviolet absorber contained in the particles may also be measured using a particle dispersion. The components contained in the particles will be described in detail below.

[0052] (Ultraviolet Absorber) The particles contained in the composition for forming an alignment film of the present invention contain an ultraviolet absorber. As described above, the ultraviolet absorber may be either a low-molecular-weight ultraviolet absorber or a polymeric ultraviolet absorber.

[0053] The maximum absorption wavelength of the ultraviolet absorber is as described above. The structure having ultraviolet absorption ability contained in the ultraviolet absorber is not particularly limited as long as it is a structure derived from a compound having a maximum absorption wavelength within the above range, and examples thereof include structures derived from compounds selected from the group consisting of benzophenone-based compounds, benzoxazinone-based compounds, anthracene-based compounds, benzotriazole-based compounds, indole-based compounds, methine-based compounds, benzodithiol-based compounds, and hydroxyphenyltriazine-based compounds. Among these, structures derived from benzodithiol-based compounds are preferred. Benzodithiol-based compounds are easy to adjust the maximum absorption wavelength to the above preferred range.

[0054] The ultraviolet absorber is preferably a specific polymer containing a repeating unit A having a structure represented by the following formula (A1).

[0055]

[0056] In formula (A1), Y １１ or Y １２ one of the groups represents a cyano group, and the other represents a cyano group, an optionally substituted alkylcarbonyl group, an optionally substituted arylcarbonyl group, an optionally substituted heterocyclic carbonyl group, an optionally substituted alkylsulfonyl group, an optionally substituted arylsulfonyl group, an optionally substituted carbamoyl group, an optionally substituted sulfamoyl group, an optionally substituted alkoxycarbonyl group, or an optionally substituted aryloxycarbonyl group. １１ is *1-L Ｖ１１ -*2. V １２ represents a hydrogen atom, a monovalent substituent, or *1-L Ｖ１２ -*2. Ｖ１１ and L Ｖ１２ Each of R independently represents a single bond or a divalent linking group. *1 represents the bonding position to the main chain of the specific polymer. *2 represents the bonding position to the benzene ring specified in formula (A1). R １１ and R １２ each independently represents a hydrogen atom or a monovalent substituent.

[0057] Y １１ and Y １２ The alkylcarbonyl group represented by the following formula (I) which may have a substituent is preferably an alkylcarbonyl group having 2 to 8 carbon atoms which may have a substituent, more preferably an acetyl group, an ethylcarbonyl group or a t-butylcarbonyl group, and even more preferably an ethylcarbonyl group or a t-butylcarbonyl group. １１ and Y １２ The optionally substituted arylcarbonyl group represented by the formula (I) is preferably an optionally substituted arylcarbonyl group having 2 to 14 carbon atoms, more preferably a benzoyl group or a naphthoyl group, and even more preferably a benzoyl group. １１ and Y １２The heterocyclic carbonyl group represented by the formula (I) and optionally having a substituent is preferably a heterocyclic carbonyl group having 2 to 14 carbon atoms and optionally having a substituent, more preferably a 2-pyridinecarbonyl group or a 2-thiophenecarbonyl group, and even more preferably a 2-pyridinecarbonyl group. The heterocycle constituting the heterocyclic carbonyl group may be either aromatic or non-aromatic. Y １１ and Y １２ The alkylsulfonyl group represented by the following formula (I) which may have a substituent is preferably an alkylsulfonyl group having 1 to 4 carbon atoms which may have a substituent, and more preferably methanesulfonyl. １１ and Y １２ The optionally substituted arylsulfonyl group represented by the following formula is preferably an optionally substituted arylsulfonyl group having 6 to 10 carbon atoms, more preferably benzenesulfonyl. １１ and Y １２ The optionally substituted carbamoyl group represented by the formula (I) is preferably an unsubstituted carbamoyl group or an optionally substituted alkylcarbamoyl group having 1 to 9 carbon atoms, more preferably an unsubstituted carbamoyl group or an optionally substituted alkylcarbamoyl group having 1 to 4 carbon atoms, and even more preferably carbamoyl, N-methylcarbamoyl, N,N-dimethylcarbamoyl or N-phenylcarbamoyl. １１ and Y １２ The optionally substituted sulfamoyl group represented by the formula (I) is preferably an optionally substituted alkylsulfamoyl group having 1 to 7 carbon atoms, an optionally substituted dialkylsulfamoyl group having 3 to 6 carbon atoms, an optionally substituted arylsulfamoyl group having 6 to 11 carbon atoms, or an optionally substituted heterocyclic sulfamoyl group having 2 to 10 carbon atoms, and more preferably sulfamoyl, methylsulfamoyl, N,N-dimethylsulfamoyl, phenylsulfamoyl, or 4-pyridinesulfamoyl. １１ and Y １２The alkoxycarbonyl group represented by the following formula (I) which may have a substituent is preferably an alkoxycarbonyl group having 2 to 4 carbon atoms which may have a substituent, more preferably methoxycarbonyl, ethoxycarbonyl or (t)-butoxycarbonyl, still more preferably methoxycarbonyl or ethoxycarbonyl, and particularly preferably ethoxycarbonyl. １１ and Y １２ The optionally substituted aryloxycarbonyl group represented by the formula (I) is preferably an optionally substituted aryloxycarbonyl group having 6 to 12 carbon atoms, more preferably an optionally substituted aryloxycarbonyl group having 6 to 10 carbon atoms, and even more preferably phenyloxycarbonyl, 4-nitrophenyloxycarbonyl, 4-acetylaminophenyloxycarbonyl or 4-methanesulfonylphenyloxycarbonyl. １１ and Y １２ Examples of the substituent that each group represented by the formula (I) may have include an alkyl group, an alkoxy group, and an aryl group, and an alkoxy group is preferred.

[0058] Y １１ or Y １２ preferably, one of represents a cyano group, and the other represents a cyano group, an optionally substituted alkylcarbonyl group, an optionally substituted arylcarbonyl group, an optionally substituted heterocyclic carbonyl group, an optionally substituted carbamoyl group, or an optionally substituted alkoxycarbonyl group; １１ or Y １２ more preferably, one of represents a cyano group, and the other represents a cyano group, an optionally substituted alkylcarbonyl group, an optionally substituted arylcarbonyl group, an optionally substituted carbamoyl group, or an optionally substituted alkoxycarbonyl group; and Y １１ or Y １２It is more preferable that one of Y represents a cyano group, and the other represents a cyano group, an optionally substituted alkylcarbonyl group having 3 to 18 carbon atoms, an optionally substituted arylcarbonyl group having 7 to 18 carbon atoms, an optionally substituted carbamoyl group, or an optionally substituted alkoxycarbonyl group having 3 to 18 carbon atoms; １１ or Y １２ It is particularly preferred that one of Y represents a cyano group and the other represents a cyano group, an ethylcarbonyl group, a t-butylcarbonyl group, a benzoyl group or an ethoxycarbonyl group; １１ and Y １２ Most preferably, represents a cyano group.

[0059] In formula (A1), V １１ is *1-L Ｖ１１ -*2. Ｖ１１ represents a single bond or a divalent linking group. Ｖ１１ Examples of the divalent linking group represented by the formula (I) include -O-, -S-, -CO-, -COO-, and -CONR Ｎ -, alkylene group, alkenylene group, arylene group, and divalent linking groups combining these. As the divalent linking group combining these, -COO-alkylene group-O- or -COO-alkylene group-CO- is preferred, and *1-COO-alkylene group-O-*2 or *1-COO-alkylene group-CO-*2 is more preferred. R Ｎ represents a hydrogen atom or a monovalent substituent. The alkylene group may be linear, branched, or cyclic, and is preferably linear. The alkylene group preferably has 1 to 30 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 5 carbon atoms. L Ｖ１１ As *1-X １ -X ２ -O-*2 or *1-X １ -X ２ -CO-*2 is also preferred. １ and X ２ is X in formula (A3) １ and X ２ The same definition and preferred embodiments are also the same.

[0060] In formula (A1), V１２ represents a hydrogen atom, a monovalent substituent, or *1-L Ｖ１２ -*2. Ｖ１２ represents a single bond or a divalent linking group. １２ Examples of the monovalent substituent represented by the formula (V) include a halogen atom, a mercapto group, a cyano group, a carboxy group, a phosphate group, a sulfo group, a hydroxyl group, a carbamoyl group, a sulfamoyl group, a nitro group, an alkoxy group, an aryloxy group, an acyl group, an acyloxy group (—OCOR), an acylamino group, a sulfonyl group, a sulfinyl group, a sulfonylamino group, an amino group, an ammonium group, a hydrazino group, a ureido group, an imido group, an alkylthio group, an arylthio group, an alkenylthio group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkyl group, and an aryl group. １２ The groups exemplified as the monovalent substituent represented by the formula １１ and Y １２ V may have a substituent group such as a substituent that V may have. １２ L is preferably a cyano group, a nitro group, a hydroxyl group, an alkoxy group, an aryloxy group, or an acyloxy group, more preferably an alkoxy group, an aryloxy group, or an acyloxy group, still more preferably an alkoxy group or an acyloxy group, and particularly preferably a methoxy group, an ethoxy group, an i-propyloxy group, a 2-ethylhexyloxy group, a 3,5,5-trimethylhexyloxy group, an acetoxy group, a propionyloxy group, an n-butyryloxy group, a t-butyryloxy group, a 2-ethylhexanoyloxy group, a 3,5,5-trimethylhexanoyloxy group, or a 4-(4-propylcyclohexyl)cyclohexylcarbonyloxy group. Ｖ１２ Examples of the divalent linking group represented by the formula: Ｖ１１ Examples of the divalent linking group include a divalent linking group represented by the following formula: １２ is a monovalent substituent or *1-L Ｖ１２ -*2 is preferable. １２ *1-L Ｖ１２ -*2, L Ｖ１２ Is, L Ｖ１１ It is also preferable that the group represents the same group as

[0061] *1 represents the bonding position with the main chain of the specific polymer. *2 represents the bonding position with the benzene ring specified in formula (A1). The benzene ring specified in formula (A1) bonded to the bonding position represented by *2 is the benzene ring constituting the benzodithiol in formula (A1), and V １１ , V １２ , R １１ and R １２ is a benzene ring to which V is directly bonded. *1 and *2 will be described in detail below using an example of a specific polymer. For example, V １１ *1-COO-(CH ２ ) ４ -O-*2, V １２ When represents a hydrogen atom, an example of the specific polymer is an embodiment having a repeating unit represented by formula (PX) as the repeating unit A. １１ *1-COO-(CH ２ ) ４ -O-*2, V １２ *1-COO-(CH ２ ) ４ When -O-*2 is represented, an example of the specific polymer is an embodiment having a repeating unit represented by formula (PY) as the repeating unit A. In formulas (PX) and (PY), Y １１ , Y １２ , R １１ and R １２ are the same as the respective symbols in formula (A1).

[0062]

[0063] In formula (A1), R １１ and R １２ R each independently represents a hydrogen atom or a monovalent substituent. １１ and R １２ Examples of the monovalent substituent represented by the formula (I) include V １２Examples of the alkyl group include a monovalent substituent represented by the formula: wherein an alkyl group which may have a substituent is preferred, and an unsubstituted alkyl group is more preferred. The alkyl group may be linear, branched, or cyclic. The number of carbon atoms in the alkyl group is preferably 1 to 30, more preferably 1 to 10, and even more preferably 1 to 5. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and a butyl group (preferably a t-butyl group). R １１ or R １２ Preferably, one of R represents a hydrogen atom and the other represents a hydrogen atom or an alkyl group which may have a substituent, and R １１ or R １２ It is more preferable that one of these groups represents a hydrogen atom and the other represents an alkyl group which may have a substituent.

[0064] The repeating unit A preferably has a structure represented by formula (A2).

[0065]

[0066] In formula (A2), V ２１ is *1-L Ｖ２１ -*2. V ２２ represents a hydrogen atom, a monovalent substituent, or *1-L Ｖ２２ -*2. Ｖ２１ and L Ｖ２２ *1 represents the bonding position with the main chain of the specific polymer. *2 represents the bonding position with the main chain of the specific polymer. *3 represents the bonding position with the main chain of the specific polymer. *4 represents the bonding position with the main chain of the specific polymer. *5 represents the bonding position with the main chain of the specific polymer. *6 represents the bonding position with the main chain of the specific polymer. *7 represents the bonding position with the main chain of the specific polymer. *8 represents the bonding position with the main chain of the specific polymer. *9 represents the bonding position with the main chain of the specific polymer. *1 represents the bonding position with the main chain of the specific polymer. *1 represents the bonding position with the main chain of the specific polymer. *2 ... ａ２１ or L ａ２２ represents the bonding position with ａ２１ and L ａ２２ R each independently represents —O— or —CO—. ２１ and R ２２ each independently represents a hydrogen atom or a monovalent substituent.

[0067] In formula (A2), V ２１ is *1-L Ｖ２１ -*2. Ｖ２１ represents a single bond or a divalent linking group. Ｖ２１ Examples of the divalent linking group represented by the formula: Ｖ１１Examples include divalent linking groups represented by the following formula: -COO-alkylene group- is preferred, and *1-COO-alkylene group-*2 is more preferred.

[0068] In formula (A2), V ２２ represents a hydrogen atom, a monovalent substituent, or *1-L Ｖ２２ -*2. Ｖ２２ represents a single bond or a divalent linking group. Ｖ２１ Examples of the divalent linking group represented by the formula: Ｖ１１ Examples include divalent linking groups represented by the following formula: -COO-alkylene group- is preferred, and *1-COO-alkylene group-*2 is more preferred. ２２ *1-L Ｖ２２ -*2, L Ｖ２２ Is, L Ｖ２１ It is also preferable that the group represents the same group as

[0069] In formula (A2), L ａ２１ and L ａ２２ each independently represents —O— or —CO—. ａ２１ and L ａ２２ is preferably —O—. ａ２１ and L ａ２２ It is also preferred that represent the same group.

[0070] In formula (A2), R ２１ and R ２２ is R １１ and R １２ The meanings of *1 and *2 in formula (A2) can be referenced to the meanings of *1 and *2 in formula (A1).

[0071] It is also preferable that the repeating unit A has a structure represented by formula (A3).

[0072]

[0073] In formula (A3), V ３１ represents a hydrogen atom, a monovalent substituent, or *1-L Ｖ３１ -*2. Ｖ３１ represents a single bond or a divalent linking group. *1 represents the bonding position with the main chain of the specific polymer. *2 represents the bonding position with the main chain of the specific polymer. ａ３１represents the bonding position with ａ３１ and L ａ３２ R each independently represents —O— or —CO—. ３１ and R ３２ R each independently represents a hydrogen atom or a monovalent substituent. ３３ represents a hydrogen atom or a methyl group. １ represents a phenylene group, —COO—, —CONH—, —O—, —CO—, or —CH ２ - represents X ２ represents a single bond or a divalent linking group.

[0074] V ３１ is V ２２ The same definition and preferred embodiments are also the same. ａ３１ and L ａ３２ Is, L ａ２１ and L ａ２２ The same definition and preferred embodiments are also the same. ３１ and R ３２ is R １１ and R １２ The same definition and preferred embodiments are also the same.

[0075] In formula (A3), X １ represents a phenylene group, —COO—, —CONH—, —O— or —CO—. １ As the group, a phenylene group, —COO— or —CONH— is preferable, and —COO— is more preferable.

[0076] In formula (A3), X ２ represents a single bond or a divalent linking group. ２ Examples of the divalent linking group represented by the formula: Ｖ２２ Examples of the divalent linking group include a divalent linking group represented by the following formula:

[0077] It is also preferable that the repeating unit A has a repeating unit derived from a monomer having at least one polymerizable group selected from the group consisting of a (meth)acrylic group, a styryl group, a (meth)acrylamide group, and a vinyl ether group.

[0078] The content of the repeating unit A is preferably 10 to 100% by mass, more preferably 30 to 100% by mass, still more preferably 40 to 100% by mass, and particularly preferably 50 to 100% by mass, relative to the total mass of the specific polymer, in terms of better effects of the present invention.

[0079] The specific polymer may have a repeating unit B in addition to the repeating unit A. The repeating unit B is a repeating unit having a hydrophilic group. Examples of the hydrophilic group include a carboxylic acid group and its salt; a sulfonic acid group and its salt; a phosphoric acid group and its salt; and nonionic hydrophilic groups such as a hydroxyl group, an amino group, a betaine group, an ethylene glycol group, a polyethylene glycol group, a propylene glycol group, a polypropylene glycol group, and an amide group. The hydrophilic group is preferably at least one group selected from the group consisting of a carboxylic acid group and its salt, a sulfonic acid group and its salt, and a hydroxyl group, and more preferably at least one group selected from the group consisting of a carboxylic acid group and its salt, and a sulfonic acid group and its salt. The number of hydrophilic groups possessed by the repeating unit B may be 1 or 2 or more.

[0080] The repeating unit B is preferably a repeating unit derived from a monomer having a hydrophilic group and a polymerizable group. The polymerizable group is preferably an ethylenically unsaturated group, more preferably a vinyl group, a (meth)acryloyl group, a styryl group, or a maleimide group, and still more preferably a vinyl group or a (meth)acryloyl group.

[0081] Examples of monomers having a carboxylic acid group or its salt and a polymerizable group include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, 2-methacryloyloxymethylsuccinic acid, β-carboxyethyl acrylate, and salts thereof. Examples of monomers having a sulfonic acid group or its salt and a polymerizable group include styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 3-sulfopropyl(meth)acrylate, bis-(3-sulfopropyl)itaconate, and salts thereof. Examples of monomers having a phosphoric acid group or its salt and a polymerizable group include vinylphosphonic acid, vinyl phosphate, bis(methacryloxyethyl)phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, dibutyl-2-acryloyloxyethyl phosphate, and salts thereof. Examples of the monomer having a nonionic hydrophilic group and a polymerizable group include ethylenically unsaturated monomers having a (poly)ethyleneoxy group or a polypropyleneoxy group, such as 2-methoxyethyl (meth)acrylate, 2-(2-methoxyethoxy)ethyl (meth)acrylate, ethoxytriethylene glycol (meth)acrylate, methoxypolyethylene glycol (molecular weight: 200 to 1000) mono(meth)acrylate, and polyethylene glycol (molecular weight: 200 to 1000) mono(meth)acrylate; and ethylenically unsaturated monomers having a hydroxyl group, such as hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, hydroxypentyl (meth)acrylate, and hydroxyhexyl (meth)acrylate.

[0082] Repeating unit B preferably has a repeating unit derived from at least one monomer selected from the group consisting of (meth)acrylic acid, itaconic acid, β-carboxyethyl (meth)acrylate, 2-(meth)acrylamido-2-methylpropanesulfonic acid, 3-sulfopropyl (meth)acrylate, and salts thereof, and 2,3-dihydroxypropyl (meth)acrylate; more preferably has a repeating unit derived from at least one monomer selected from the group consisting of (meth)acrylic acid, itaconic acid, β-carboxyethyl (meth)acrylate, 2-(meth)acrylamido-2-methylpropanesulfonic acid, 3-sulfopropyl (meth)acrylate, and salts thereof; and even more preferably has a repeating unit derived from at least one monomer selected from the group consisting of (meth)acrylic acid, β-carboxyethyl (meth)acrylate, 2-(meth)acrylamido-2-methylpropanesulfonic acid, 3-sulfopropyl (meth)acrylate, and salts thereof.

[0083] Examples of the salts of the carboxylic acid group, the salts of the sulfonic acid group, and the salts of the phosphate group include alkali metal salts (e.g., lithium salts, sodium salts, potassium salts, etc.), alkaline earth metal salts (e.g., barium salts, calcium salts, etc.), and ammonium salts, with alkali metal salts being preferred.

[0084] The repeating unit B is preferably a repeating unit represented by formula (B).

[0085]

[0086] In formula (B), R Ｂ represents a hydrogen atom or a methyl group. Ｂ represents a single bond or a divalent linking group. Z represents a hydrophilic group. The hydrophilic group represented by Z is as described above. L Ｂ Examples of the divalent linking group represented by the formula: Ｖ１１ Examples of the divalent linking group include —COO—, an alkylene group, —CONR Ｎ- and divalent linking groups combining these are preferred. As a substituent that the alkylene group may have, a hydrophilic group that the repeating unit B has is preferred, and a hydroxyl group is more preferred. Ｎ represents a hydrogen atom or a monovalent substituent.

[0087] When the specific polymer has the repeating unit B, the content of the repeating unit B is preferably 1 to 90 mass %, more preferably 1 to 70 mass %, even more preferably 1 to 50 mass %, particularly preferably 5 to 40 mass %, and most preferably 7 to 30 mass %, relative to the total mass of the specific polymer.

[0088] The specific polymer may have a repeating unit C other than the repeating unit A and the repeating unit B. Examples of the repeating unit C include a repeating unit derived from an alkyl (meth)acrylate.

[0089] The weight average molecular weight of the specific polymer is preferably from 1,000 to 500,000, more preferably from 1,000 to 100,000, even more preferably from 1,000 to 500,000, and particularly preferably from 3,000 to 50,000.

[0090] The content of the ultraviolet absorber relative to the total mass of the particles is preferably 5 to 100 mass%, more preferably 20 to 100 mass%. When the ultraviolet absorber is a polymeric ultraviolet absorber, the content of repeating units having ultraviolet absorbing ability relative to all repeating units of the polymeric ultraviolet absorber is preferably 5 to 100 mass%, more preferably 20 to 100 mass%.

[0091] (Binder) The particles may contain a binder as a component other than the ultraviolet absorber. The binder is not particularly limited, but examples thereof include acrylic resin, urethane resin, styryl resin, silicone resin, epoxy resin, ester resin, and diene polymer, and acrylic resin is preferred.

[0092] (Polymerizable Group) The particles may have a polymerizable group, and it is preferable that the particles have a polymerizable group on their surface. Examples of the polymerizable group include a radical polymerizable group and a cationically polymerizable group. Examples of the radical polymerizable group and the cationically polymerizable group are the same as those of the polymerizable compound described below. In the above embodiment, it is sufficient that the particles have a polymerizable group, and the polymerizable group may be bonded to an ultraviolet absorber or to a component other than the ultraviolet absorber (for example, a binder). Methods for obtaining particles having a polymerizable group include a method for obtaining particles using an ultraviolet absorber having a polymerizable group, a method for obtaining particles using a binder having a polymerizable group, and a method for modifying the surface of particles not having a polymerizable group with a compound having a polymerizable group.

[0093] Commercially available particles containing an ultraviolet absorber may be used, such as Tinuvin (registered trademark, hereinafter the same) DW series (Tinuvin 400-DW, Tinuvin 477-DW, Tinuvin 479-DW, Tinuvin 49945-DW, Tinuvin 123-DW, Tinuvin 249-DW, etc.) manufactured by BASF, and SE-2915E manufactured by Taisei Fine Chemical Co., Ltd.

[0094] For example, when the ultraviolet absorber is a specific polymer, a method for obtaining particles containing an ultraviolet absorber includes a method in which the solid obtained by precipitating the specific polymer is pulverized using a ball mill, a roll mill, or the like. Methods for precipitating the specific polymer include a method in which the specific polymer is dissolved in a good solvent for the specific polymer and then brought into contact with a poor solvent, and a method in which the solvent component is removed from a solution containing the specific polymer. Furthermore, particles containing an ultraviolet absorber can also be obtained by a method in which self-dispersing particles are obtained by phase inversion emulsification.

[0095] The method for producing particles containing an ultraviolet absorber is not particularly limited, but particles obtained by a phase inversion emulsification method are preferred. For example, the phase inversion emulsification method involves first dissolving or dispersing an ultraviolet absorber (e.g., a specific polymer) in a solvent (e.g., a water-soluble organic solvent). Next, the mixture is added to water without adding a surfactant, and the salt-forming groups (e.g., acidic groups) of the ultraviolet absorber are neutralized, followed by stirring and mixing, and then removing the solvent. According to the above procedure, an aqueous dispersion of particles containing an ultraviolet absorber can be obtained.

[0096] The content of the particles is preferably 0.1 to 30% by mass, more preferably 0.5 to 25% by mass, even more preferably 1 to 20% by mass, particularly preferably 1 to 10% by mass, and most preferably 1 to 5% by mass, based on the total solid content of the composition for forming an alignment film. One type of particle may be used alone, or two or more types may be used. When two or more types of particles are used, it is preferable that the total amount thereof is within the above-mentioned preferred content range.

[0097] [Polymerizable Compound] The polymerizable compound is a compound having a polymerizable group. Examples of the polymerizable group of the polymerizable compound include a radical polymerizable group, a cation polymerizable group, and an anion polymerizable group, and a radical polymerizable group or a cation polymerizable group is preferred. The polymerizable compound may have multiple types of polymerizable groups. For example, the polymerizable compound may be a compound having a radical polymerizable group and a cation polymerizable group.

[0098] As the radical polymerizable group, a generally known radical polymerizable group can be used, and an acryloyloxy group or a methacryloyloxy group is preferred. As the cationic polymerizable group, a generally known cationic polymerizable group can be used, and 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 these, an alicyclic ether group or a vinyloxy group is preferred, and an epoxy group, an oxetanyl group, or a vinyloxy group is more preferred.

[0099] The polymerizable compound may be a polymer having a repeating unit, or may be a compound having no repeating unit. When the polymerizable compound is a polymer having a repeating unit, examples of the polymerizable compound include polyvinyl alcohol resins, polyimide resins, (meth)acrylic resins, siloxane resins, and cycloolefin resins. Among them, vinyl alcohol resins or (meth)acrylic resins are preferred, and vinyl alcohol resins are more preferred.

[0100] When the polymerizable compound is a vinyl alcohol resin, examples thereof include polymerizable compounds represented by the following general formula (I).

[0101]

[0102] In general formula (I), L １１ represents an ether bond, a urethane bond, or an ester bond. ｔ１ represents an alkylene group or an alkyleneoxy group. １２ is R ｔ１ and Q １１ In general formula (I), Q represents a linking group that bonds to １１ represents a polymerizable group. In general formula (I), x1 is 10 to 99.9 mol%, y1 is 0.01 to 80 mol%, and z1 is 0 to 70 mol%, provided that x1 + y1 + z1 = 100. Preferably, x1 is 50 to 99.9 mol%. Preferably, y1 is 0.01 to 50 mol%, more preferably 0.01 to 20 mol%, even more preferably 0.01 to 10 mol%, and particularly preferably 0.01 to 5 mol%. Preferably, z1 is 0.01 to 50 mol%. In general formula (I), k and h each represent an integer of 0 or 1.

[0103] In general formula (I), R ｔ１ R preferably represents an alkylene group having 1 to 24 carbon atoms, and more preferably represents an alkylene group having 1 to 12 carbon atoms. ｔ１ The methylene group contained in the formula (I) is —O—, —CO—, —NH—, or —NR ７ - (R ７represents an alkyl group having 1 to 4 carbon atoms or an aryl group having 6 to 15 carbon atoms), -S-, and -SO ２ - may be substituted with one or more selected from the group consisting of

[0104] L １２ preferably represents -O-, -S-, -CO-, -O-CO-, -O-CO-O-, -CO-O-CO-, -CONR-, -NR-, -NRCONR-, or -NRCO-O- (wherein R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms). １２ ) ｈ -Q １２ preferably represents a vinyl group, a vinyloxy group, an acryloyl group, a methacryloyl group, a crotonoyl group, an acryloyloxy group, a methacryloyloxy group, a crotonoyloxy group, a vinylphenoxy group, a vinylbenzoyloxy group, a styryl group, a 1,2-epoxyethyl group, a 1,2-epoxypropyl group, a 2,3-epoxypropyl group, a 1,2-iminoethyl group, a 1,2-iminopropyl group, or a 2,3-iminopropyl group. １２ ) ｈ -Q １２ more preferably represents a vinyl group, a vinyloxy group, an acryloyl group, a methacryloyl group, an acryloyloxy group, a methacryloyloxy group, a crotonoyloxy group, a vinylbenzoyloxy group, a 1,2-epoxyethyl group, a 1,2-epoxypropyl group, a 2,3-epoxypropyl group, a 1,2-iminoethyl group, a 1,2-iminopropyl group, or a 2,3-iminopropyl group, and further preferably represents an acryloyl group, a methacryloyl group, an acryloyloxy group, or a methacryloyloxy group.

[0105] When the polymerizable compound is a vinyl alcohol resin, examples thereof include polymerizable compounds represented by the following general formula (III).

[0106]

[0107] In formula (III), L ３１ represents an ether bond, a urethane bond, or an ester bond. ３１represents an arylene group which may have a substituent. The substituent which the arylene group may have includes one or more groups selected from the group consisting of a halogen atom, an alkyl group, and an alkoxy group. ３１ is preferably an arylene group having 6 to 24 carbon atoms, or an arylene group having 6 to 24 carbon atoms substituted with one or more substituents selected from the group consisting of halogen, an alkyl group having 1 to 4 carbon atoms, and an alkoxy group having 1 to 4 carbon atoms. ｔ１ is R ｔ１ In formula (III), L ３２ Is, L １２ In formula (III), Q represents the same group as ３１ Is, Q １１ represents the same group as in formula (III). In formula (III), x2 is 10 to 99.9 mol%, y2 is 0.01 to 80 mol%, and z2 is 0 to 70 mol%, provided that x2 + y2 + z2 = 100. Preferably, x2 is 50 to 99.9 mol%. Preferably, y2 is 0.01 to 50 mol%, more preferably 0.01 to 20 mol%, even more preferably 0.01 to 10 mol%, and particularly preferably 0.01 to 5 mol%. Preferably, z2 is 0.01 to 50 mol%. In formula (III), k1 and h1 each represent an integer of 0 or 1. In formula (III), f represents an integer of 0 or 1.

[0108] It is also preferable that the hydrogen atom of the hydroxyl group contained in the repeating unit subscripted x1 in general formula (I) or the hydrogen atom of the hydroxyl group contained in the repeating unit subscripted x2 in general formula (III) is substituted with a repeating unit represented by the following formula (II):

[0109]

[0110] In formula (II), R ｔ２ represents an alkyl group or an alkyl group substituted with an alkoxy group, an allyl group, a halogen atom, a vinyl group, a vinyloxy group, an oxiranyl group, an acryloyloxy group, a methacryloyloxy group, or a crotonoyloxy group. ２１represents an alkyl group or an alkoxy group. The alkyl group may be substituted with an alkoxy group, an aryl group, a halogen atom, a vinyl group, a vinyloxy group, an oxiranyl group, an acryloyloxy group, a methacryloyloxy group, or a crotonoyloxy group. The alkoxy group may be substituted with an alkyl group, an alkoxy group, an aryl group, a halogen atom, a vinyl group, a vinyloxy group, an oxiranyl group, an acryloyloxy group, a methacryloyloxy group, or a crotonoyloxy group. In formula (II), q represents an integer of 0 or 1. In formula (II), n represents an integer of 0 to 4, preferably 0 or 1, and more preferably 0.

[0111] When the polymerizable compound represented by general formula (I) or general formula (III) has a repeating unit having a group of general formula (II), the repeating unit having a group of general formula (II) preferably accounts for 0.1 to 10 mol %, more preferably 0.1 to 5 mol %, of the total repeating units of the compound represented by general formula (I) or general formula (III).

[0112] When the polymerizable compound is a vinyl alcohol resin, the polymerizable compound described in JP-A-09-152509 can also be suitably used. The above publication can also be referenced for the synthesis method of the polymerizable compound represented by general formula (I) or general formula (III).

[0113] When the alignment film is a photo-alignment film, the polymerizable compound preferably has a repeating unit having a photo-alignment group. The photo-alignment group is preferably a group that undergoes at least one of dimerization and isomerization by the action of light.

[0114] Specific examples of groups that dimerize under the action of light include groups having a skeleton of at least one derivative selected from the group consisting of cinnamic acid derivatives, coumarin derivatives, chalcone derivatives, maleimide derivatives, and benzophenone derivatives. On the other hand, specific examples of groups that isomerize under the action of light include groups having a skeleton of at least one compound selected from the group consisting of azobenzene compounds, stilbene compounds, spiropyran compounds, cinnamic acid compounds, and hydrazono-β-ketoester compounds. Among these photoalignable groups, groups having a skeleton of at least one derivative or compound selected from the group consisting of cinnamic acid derivatives, coumarin derivatives, chalcone derivatives, maleimide derivatives, azobenzene compounds, stilbene compounds, and spiropyran compounds are preferred. Among these, groups having a skeleton of a cinnamic acid derivative or an azobenzene compound are more preferred, and groups having a skeleton of a cinnamic acid derivative (hereinafter also referred to as "cinnamoyl group") are even more preferred.

[0115] As the polymerizable compound having a repeating unit having a photoalignable group, a copolymer having a repeating unit AX represented by the following formula (A) and a repeating unit BX represented by the following formula (B) is preferred.

[0116]

[0117] In the above formula (A), R １ represents a hydrogen atom or a methyl group. １ represents a divalent linking group. ２ , R ３ , R ４ , R ５ and R ６ each independently represents a hydrogen atom or a substituent, R ２ , R ３ , R ４ , R ５ and R ６ In the above formula (B), two adjacent groups may be bonded to form a ring. ７ represents a hydrogen atom or a methyl group, L ２ represents a divalent linking group, and X represents a polymerizable group.

[0118] In formula (A), L １ represents a divalent linking group. １ is preferably a divalent linking group formed by combining at least two or more groups selected from the group consisting of an optionally substituted linear, branched, or cyclic alkylene group having 1 to 18 carbon atoms, an optionally substituted arylene group having 6 to 12 carbon atoms, an ether group (—O—), a carbonyl group (—C(═O)—), and an optionally substituted imino group (—NH—). １ also preferably represents a divalent linking group containing a nitrogen atom and a cycloalkane ring, and some of the carbon atoms constituting the cycloalkane ring may be substituted with a heteroatom selected from the group consisting of nitrogen, oxygen, and sulfur.

[0119] In order to improve the liquid crystal alignment property, L １ is also preferably a divalent linking group represented by any one of the following formulas (1) to (10).

[0120] In the above formulas (1) to (10), *1 represents the bonding position to the carbon atom constituting the main chain in the above formula (A), and *2 represents the bonding position to the carbon atom constituting the carbonyl group in the above formula (A).

[0121] Next, R in the above formula (A) ２ , R ３ , R ４ , R ５ and R ６ The substituents represented by one embodiment of the formula (A) will be described below. ２ , R ３ , R ４ , R ５ and R ６ However, as described above, it may be a hydrogen atom instead of a substituent.

[0122] R in the above formula (A) ２ , R ３ , R ４ , R ５ and R ６The substituents represented by one aspect of the formula (11) are each independently preferably a halogen atom, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, a linear halogenated alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a cyano group, an amino group, or a group represented by the following formula (11), because the photoalignable group is more likely to interact with the liquid crystal compound and the liquid crystal alignment is more favorable.

[0123] In the formula (11), * represents the bonding position with the benzene ring in the formula (A), and R ９ represents a monovalent organic group. ９ Examples of the monovalent organic group represented by include linear or cyclic alkyl groups having 1 to 20 carbon atoms. As the linear alkyl group, alkyl groups having 1 to 6 carbon atoms are preferred, and specific examples thereof include methyl, ethyl, and n-propyl groups, with methyl and ethyl groups being preferred. As the cyclic alkyl group, alkyl groups having 3 to 6 carbon atoms are preferred, and specific examples thereof include cyclopropyl, cyclopentyl, and cyclohexyl groups, with cyclohexyl being preferred. Note that R in the above formula (11) ９ The monovalent organic group represented by R may be a combination of the above-mentioned linear alkyl groups and cyclic alkyl groups either directly or via a single bond. ４ is also preferably a group represented by formula (11).

[0124] In formula (B), L ２ represents a divalent linking group. ２ The divalent linking group represented by is L in the above formula (A). １ Examples of the divalent linking group include those described above for the divalent linking group represented by the formula:

[0125] In formula (B), X represents a polymerizable group. Specific examples of X (polymerizable group) in formula (B) include an epoxy group, an epoxycyclohexyl group, an oxetanyl group, and a functional group having an ethylenically unsaturated double bond. Among these, at least one polymerizable group selected from the group consisting of the following formulae (X1) to (X4) is preferred.

[0126]

[0127] In the above formulas (X1) to (X4), * represents L in the above formula (B). ２ represents the bonding position with R ８ represents a hydrogen atom, a methyl group, or an ethyl group, and in the above formula (X4), S represents a functional group having an ethylenically unsaturated double bond. Specific examples of the functional group having an ethylenically unsaturated double bond include a vinyl group, an allyl group, a styryl group, an acryloyl group, and a methacryloyl group, and an acryloyl group or a methacryloyl group is preferred.

[0128] The polymerizable compound having a repeating unit having a photoalignment group may have other repeating units in addition to the repeating unit AX and the repeating unit BX described above. Examples of the monomer (radical polymerizable monomer) that forms such other repeating units include acrylic acid ester compounds, methacrylic acid ester compounds, maleimide compounds, acrylamide compounds, acrylonitrile, maleic anhydride, styrene compounds, and vinyl compounds.

[0129] The synthesis method of the copolymer is not particularly limited, and the copolymer can be synthesized, for example, by mixing a monomer forming the repeating unit AX described above, a monomer forming the repeating unit BX described above, and a monomer forming any other repeating unit, and polymerizing the mixture in an organic solvent using a radical polymerization initiator.

[0130] The weight-average molecular weight (Mw) of the copolymer is preferably 10,000 to 500,000, more preferably 10,000 to 100,000. Here, the weight-average molecular weight and number-average molecular weight are values ​​measured by gel permeation chromatography (GPC) under the following conditions: Solvent (eluent): THF (tetrahydrofuran) Apparatus name: TOSOH HLC-8320GPC Column: Three TOSOH TSKgel Super HZM-H (4.6 mm x 15 cm) columns connected together Column temperature: 40°C Sample concentration: 0.1% by mass Flow rate: 1.0 ml / min Calibration curve: A calibration curve using seven samples of TSK standard polystyrene manufactured by TOSOH with Mw = 2,800,000 to 1,050 (Mw / Mn = 1.03 to 1.06) was used.

[0131] When the polymerizable compound has a repeating unit having a photoalignment group, the polymerizable compounds described in WO 2019 / 225632 and WO 2020 / 179864 can also be suitably used.

[0132] The content of the polymerizable compound is preferably 50 to 99.9% by mass, more preferably 60 to 99% by mass, even more preferably 70 to 99% by mass, particularly preferably 80 to 99% by mass, and most preferably 85 to 99% by mass, based on the total solid content of the composition for forming an alignment film. One type of polymerizable compound may be used alone, or two or more types may be used. When two or more types of polymerizable compounds are used, it is preferable that the total amount thereof is within the above-mentioned preferred content range.

[0133] [Solvent] The composition for forming an alignment film may contain a solvent. Examples of the solvent include water and organic solvents. The organic solvent is preferably an organic solvent that is miscible with water at any ratio. It is preferable to select a solvent that does not dissolve the components contained in the particles. Examples of the organic solvent include alcohol-based solvents, glycol-based solvents, glycol ether-based solvents, ketone-based solvents, amide-based solvents, and sulfur-containing solvents.

[0134] Examples of alcohol-based solvents include methanol, ethanol, propanol, isopropyl alcohol, 1-butanol, 2-butanol, isobutyl alcohol, and tert-butyl alcohol.

[0135] Examples of glycol-based solvents include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, and tetraethylene glycol.

[0136] Examples of glycol ether solvents include glycol monoethers, such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, 1-methoxy-2-propanol, 2-methoxy-1-propanol, 1-ethoxy-2-propanol, 2-ethoxy-1-propanol, propylene glycol mono-n-propyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monobenzyl ether, and diethylene glycol monobenzyl ether.

[0137] Examples of ketone solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

[0138] Examples of amide solvents include N,N-dimethylformamide, 1-methyl-2-pyrrolidone, 2-pyrrolidinone, 1,3-dimethyl-2-imidazolidinone, 2-pyrrolidinone, formamide, N-methylformamide, acetamide, N-methylacetamide, N,N-dimethylacetamide, N-methylpropanamide, and hexamethylphosphoric triamide.

[0139] Examples of sulfur-containing solvents include dimethyl sulfone, dimethyl sulfoxide, and sulfolane.

[0140] The content of the solvent is preferably 60 to 99.9% by mass, more preferably 70 to 99% by mass, and even more preferably 80 to 99% by mass, based on the total mass of the composition for forming an alignment film. One solvent may be used alone, or two or more solvents may be used. When two or more solvents are used, it is preferable that the total amount thereof is within the above-mentioned preferred content range.

[0141] [Polymerization Initiator] The composition for forming an alignment film may contain a polymerization initiator. The polymerization initiator is selected depending on the type of polymerization reaction, and examples thereof include thermal polymerization initiators and photopolymerization initiators. Examples of thermal polymerization initiators include azo compounds and peroxide compounds. Examples of photopolymerization initiators include α-carbonyl compounds, acyloin ethers, α-hydrocarbon-substituted aromatic acyloin compounds, polynuclear quinone compounds, and combinations of triarylimidazole dimers and p-aminophenyl ketones. When the composition for forming an alignment film contains a polymerization initiator, the content of the polymerization initiator is preferably 0.01 to 30% by mass, more preferably 0.5 to 20% by mass, based on the total solids content of the composition for forming an alignment film.

[0142] [Additives] The composition for forming an alignment film may contain other components in addition to those described above, and examples of the other components include additives such as a refractive index adjuster, an elastic modulus adjuster, a crosslinking agent, a filler, an adhesion improver, a leveling agent, a surfactant, and a plasticizer. Among these, it is also preferable to use a crosslinking agent, and it is preferable that the crosslinkable group of the crosslinking agent can react with the polymerizable group of the polymerizable compound contained in the composition for forming an alignment film.

[0143] <Polarizing Plate> The polarizing plate of the present invention includes the above-mentioned optical film and a polarizer. A polarizing plate is a plate that converts unpolarized light into light of a certain polarized state, and specific examples include a linear polarizing plate, an elliptical polarizing plate, and a circular polarizing plate. The polarizing plate is preferably a linear polarizing plate or a circular polarizing plate.

[0144] When the optical film included in the optical film is a λ / 4 plate, the polarizing plate of the present invention can be suitably used as a circular polarizing plate. When the polarizing plate of the present invention is used as a circular polarizing plate, the optical film of the present invention described above is used as a λ / 4 plate, and the angle formed between the slow axis of the λ / 4 plate and the absorption axis of a polarizer described below is preferably 30 to 60°, more preferably 40 to 50°, even more preferably 42 to 48°, and particularly preferably 45°.

[0145] The polarizing plate of the present invention can also be used as an optical compensation film for an IPS (In-Plane-Switching) mode or FFS (Fringe-Field-Switching) mode liquid crystal display device. When the polarizing plate of the present invention is used as an optical compensation film for an IPS mode or FFS mode liquid crystal display device, the above-mentioned optical film of the present invention is a laminate of a positive A plate and a positive C plate, and the angle between the slow axis of the positive A plate and the absorption axis of the polarizer described below is preferably orthogonal or parallel. Specifically, the angle between the slow axis of the positive A plate and the absorption axis of the polarizer described below is more preferably 0 to 5° or 85 to 95°. Here, the "slow axis" of the λ / 4 plate or positive A plate refers to the direction in which the refractive index is maximum in the plane of the λ / 4 plate or positive A plate, and the "absorption axis" of the polarizer refers to the direction in which the absorbance is highest.

[0146] [Polarizer] The polarizer of the polarizing plate of the present invention is not particularly limited as long as it has the function of converting light into specific linearly polarized light, and conventionally known absorptive polarizers and reflective polarizers can be used. Examples of absorptive polarizers include iodine-based polarizers, dye-based polarizers using dichroic dyes, and polyene-based polarizers. Iodine-based polarizers and dye-based polarizers include coated polarizers and stretched polarizers, and either type is applicable. However, polarizers produced by adsorbing iodine or a dichroic dye onto polyvinyl alcohol and stretching the resulting film are preferred. Furthermore, methods for obtaining a polarizer by stretching and dyeing a laminated film having a polyvinyl alcohol layer formed on a substrate include those described in Japanese Patent Nos. 5,048,120, 5,143,918, 4,691,205, 4,751,481, and 4,751,486. These known techniques for polarizers can also be preferably used. As the reflective polarizer, a polarizer in which thin films with different birefringence are laminated, a wire grid polarizer, and a polarizer in which a cholesteric liquid crystal having a selective reflection region is combined with a quarter-wave plate are used. Among them, a polyvinyl alcohol resin (-CH２ A polarizer containing a polymer containing —CHOH— as a repeating unit, particularly at least one selected from the group consisting of polyvinyl alcohol and an ethylene-vinyl alcohol copolymer, is preferred.

[0147] The thickness of the polarizer is not particularly limited, but is preferably from 3 to 60 μm, more preferably from 3 to 30 μm, and even more preferably from 3 to 10 μm.

[0148] The polarizing plate of the present invention may have other components in addition to the polarizer and the optical film, such as a retardation layer, an optical compensation film, a pressure-sensitive adhesive layer, an adhesive layer, a refractive index adjusting layer, a barrier layer, and a color adjusting layer.

[0149] <Method for Manufacturing Polarizing Plate> The method for manufacturing a polarizing plate of the present invention includes the steps of: applying the above-described composition for forming an alignment film onto a support to form a first coating film and subjecting the first coating film to an alignment treatment (hereinafter also referred to as "Step 1"); applying a composition containing a liquid crystal compound onto the first coating film that has been subjected to the alignment treatment to form a second coating film (hereinafter also referred to as "Step 2"); curing the first coating film and the second coating film to form an alignment film and an optically anisotropic layer, thereby forming a laminate including the support, the alignment film, and the optically anisotropic layer (hereinafter also referred to as "Step 3"); and bonding the laminate and the polarizer so that the optically anisotropic layer faces the polarizer, and peeling the support from the resulting bonded product to obtain a polarizing plate including the polarizer, the optically anisotropic layer, and the alignment film (hereinafter also referred to as "Step 4"). Each step will be described below.

[0150] [Step 1] In step 1, a composition for forming an alignment film is applied onto a support to form a first coating film, and the first coating film is subjected to an alignment treatment. The composition for forming an alignment film is as described above.

[0151] Examples of the support include glass substrates and polymer films. Materials for the polymer film include cellulose-based polymers; acrylic polymers such as polymethyl methacrylate; 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; and polymers containing a mixture of these polymers. The support may be peeled off after the polarizing plate is formed.

[0152] The thickness of the support is not particularly limited, but is preferably from 5 to 200 μm, more preferably from 10 to 100 μm, and even more preferably from 20 to 90 μm.

[0153] The method for applying the composition for forming an alignment film is not particularly limited, and any known method may be used, such as air knife coating, curtain coating, roller coating, wire bar coating, gravure coating, and die coating.

[0154] The alignment treatment for the first coating film may be selected depending on the type of composition for forming an alignment film. When the alignment film formed by the composition for forming an alignment film is a photo-alignment film, the alignment treatment may be a light irradiation treatment. The light irradiation treatment may be an ultraviolet irradiation treatment. The ultraviolet light irradiated in the ultraviolet irradiation treatment may be unpolarized ultraviolet light or linearly polarized ultraviolet light. Furthermore, unpolarized ultraviolet light and linearly polarized ultraviolet light may be used in combination. When the alignment film formed by the composition for forming an alignment film is not a photo-alignment film, the alignment treatment may be, for example, a rubbing treatment. Known methods can be used for the rubbing treatment, and examples include a method of rubbing the surface of the first coating film several times in a certain direction with paper or cloth. The direction of the rubbing treatment can be appropriately set depending on the direction in which the liquid crystal compound is desired to be aligned.

[0155] Before the alignment treatment is performed on the first coating film, a treatment for removing the solvent contained in the composition for forming an alignment film may be performed. A method for removing the solvent includes a heat treatment. The temperature for the heat treatment can be appropriately set depending on the type of solvent contained in the composition for forming an alignment film, but a temperature of 50 to 150°C is preferred.

[0156] [Step 2] In step 2, a composition containing a liquid crystal compound (liquid crystal composition) is applied onto the first coating film that has been subjected to the alignment treatment to form a second coating film. The liquid crystal composition is as described above. The method for applying the liquid crystal composition is not particularly limited, and known methods can be applied, for example, the methods described in the application method for the composition for forming an alignment film can be applied. After applying the liquid crystal composition, the solvent contained in the liquid crystal composition may be removed. The removal method is not particularly limited, and examples include natural drying, reduced pressure treatment, and heating. The heating temperature may be set appropriately depending on the type of solvent, and is, for example, 40 to 200°C.

[0157] A treatment for aligning the liquid crystal compound contained in the second coating film may be performed between step 2 and step 3 described below. The treatment for aligning the liquid crystal compound is not particularly limited, and known methods can be used. Methods for aligning the liquid crystal compound include applying an electric field to the second coating film and heating to cause a phase transition to a liquid crystal phase, among which heating is preferred. The heating temperature may be selected depending on the liquid crystal compound contained in the second coating film, and may be 40 to 200°C, with 90 to 150°C being preferred. The treatment for aligning the liquid crystal compound may be performed simultaneously with the heating performed to remove the solvent that may be contained in the second coating film. If heating is performed, it is also preferable to perform a treatment after heating at a temperature lower than that of the alignment treatment in order to stabilize the alignment direction of the liquid crystal compound. The temperature is preferably 40 to 100°C, more preferably 40 to 80°C.

[0158] Furthermore, when the second coating film contains a chiral agent, ultraviolet irradiation may be performed to change the helical twisting power of the chiral agent. This ultraviolet irradiation is preferably performed in an oxygen-containing atmosphere. After ultraviolet irradiation, heat treatment may be performed again.

[0159] The ultraviolet light to be irradiated refers to electromagnetic waves mainly containing electromagnetic waves with wavelengths of 200 to 400 nm, and preferably mainly containing electromagnetic waves with wavelengths of 300 to 400 nm. The light source of the ultraviolet light is not particularly limited, and known light sources can be used, and ultraviolet light containing any wavelength range may be irradiated using a filter or the like. Examples of the light source of the ultraviolet light include a high-pressure mercury lamp, a metal halide lamp, and a light-emitting diode (LED). The irradiation dose of the ultraviolet light may be set appropriately, but is preferably 5 to 100 mJ / cm. ２ is preferred, and 10 to 50 mJ / cm ２ is more preferred.

[0160] [Step 3] In step 3, the first coating film and the second coating film are subjected to a curing treatment to form an alignment film and an optically anisotropic layer, thereby forming a laminate including the support, the alignment film, and the optically anisotropic layer. The curing treatment is preferably an ultraviolet irradiation treatment. The ultraviolet irradiation treatment is preferably carried out in an atmosphere with a low oxygen concentration. The oxygen concentration of the atmosphere in which the ultraviolet irradiation treatment is carried out is preferably 2000 volume ppm or less, more preferably 1000 volume ppm or less, and even more preferably 500 volume ppm or less. The lower limit of the oxygen concentration is 0 volume ppm or more. The ultraviolet irradiation treatment is also preferably carried out under temperature control. The temperature of the first coating film and the second coating film during the ultraviolet irradiation treatment can be adjusted appropriately depending on the components contained in the first coating film and the second coating film, but is preferably 150 to 120°C, more preferably 60 to 100°C.

[0161] [Step 4] In step 4, the laminate and the polarizer are bonded together so that the optically anisotropic layer and the polarizer face each other, and the support is peeled off from the resulting bonded product to obtain a polarizing plate including the polarizer, the optically anisotropic layer, and the alignment film. Examples of the polarizer include the polarizers described above. The method for bonding the polarizer and the laminate is not particularly limited, but examples include a method in which a pressure-sensitive adhesive or adhesive is applied to the surface of the laminate facing the optically anisotropic layer or the surface of the polarizer, followed by bonding. Known pressure-sensitive adhesives and adhesives can be used. The support can be peeled off by a known method.

[0162] <Image display device> The polarizing plate of the present invention can be applied to, for example, an image display device. 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") display panel, and a plasma display panel. Of these, a liquid crystal cell or an organic EL display panel is preferred. That is, as the image display device to which the polarizing plate of the present invention is applied, a liquid crystal display device using a liquid crystal cell as the display element, or an organic EL display device using an organic EL display panel as the display element is preferred.

[0163] The liquid crystal cell used in the liquid crystal display device is preferably, but not limited to, a VA (Vertical Alignment) mode, an OCB (Opticaly Compensated Bend) mode, an IPS (In-Plane-Switching) mode, an FFS (Fringe-Field-Switching) mode, or a TN (Twisted Nematic) mode. A preferred embodiment of the liquid crystal display device, which is an example of the image display device of the present invention, has, for example, a polarizer, the optical film of the present invention, and a liquid crystal cell in this order from the viewing side.

[0164] An organic EL display device, which is one example of the image display device of the present invention, preferably has, from the viewing side, a polarizer, the optical film of the present invention, and an organic EL display panel. The organic EL display panel is a component in which an emitting layer or multiple organic compound thin films including an emitting layer are formed between a pair of electrodes, an anode and a cathode. In addition to the emitting layer, the organic EL display panel may also have a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, a protective layer, etc., and each of these layers may have other functions. Various materials can be used to form each layer.

[0165] The present invention will be described in more detail below with reference to examples. The materials, amounts used, ratios, treatment details, 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.

[0166] <Preparation of Optical Film> A method for preparing the supported optical film used in Example 1 will be described below.

[0167] [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. The resulting composition was then filtered through filter paper with an average pore size of 34 μm and a sintered metal filter with an average pore size of 10 μm to prepare a dope. The solid concentration of the dope was 23.5 mass%, the amount of plasticizers (sugar ester compounds 1 and 2) 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). Cellulose acylate dope (1) ------------------------------------------------- Cellulose acylate (acetyl substitution degree 2.86, viscosity average degree of polymerization 310) 100 parts by mass Sugar ester compound 1 (shown in chemical formula (S4)) 6.0 parts by mass Sugar ester compound 2 (shown in 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) -------------------------------------------------

[0168] Sugar ester compounds 1 and 2

[0169] The dope prepared by the above procedure was cast using a drum film-forming machine. 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. The cast web (film) was peeled off from the drum and dried for 20 minutes in a tenter apparatus, in which both ends of the web were clipped and transported at 30 to 40°C. Subsequently, the web was post-dried by zone heating while being transported by a roll. The resulting web was knurled and then wound up to prepare a support (1).

[0170] (Alkaline Saponification Treatment) The cellulose acylate film was passed through a dielectric heating roll at a temperature of 60° C. to raise the film surface temperature to 40° C. Thereafter, an alkaline solution having the composition shown below was applied to the band surface of the film using a bar coater in an amount of 14 mL / m ２ The coated substrate was then transported for 10 seconds under a steam-type far-infrared heater manufactured by Noritake Co., Ltd. that had been heated to 110° C. Subsequently, pure water was applied at a rate of 3 mL / m using the same bar coater. ２ The film was then washed with water using a fountain coater and drained with an air knife three times, and then transported to a drying zone at 70°C for 10 seconds to dry, thereby preparing an alkaline saponified cellulose acylate film. １４ H ２９ O (CH ２ CH ２ O) ２０ H 1.0 mass part Propylene glycol 14.8 mass parts

[0171] (Formation of first coating film) On the surface of the cellulose acylate film that had been subjected to alkaline saponification treatment, a composition O1 for forming an alignment film having the following composition was continuously applied with a #14 wire bar to form a coating film (first coating film). The first coating film was dried with hot air at 60°C for 60 seconds and then with hot air at 100°C for 120 seconds.

[0172] ------------------------------------------------------------------ Composition O1 for forming alignment film -------------------------------------------------- Polymerizable compound P1 100 parts by mass Ultraviolet absorber U1 (described below) 5.0 parts by mass Photopolymerization initiator (described below) 7.5 parts by mass Water 2620 parts by mass Methanol 873 parts by mass ------------------------------------------------------------------

[0173] Polymerizable compound P1 (wherein the numerical value shown for each repeating unit represents the content (mol %) of each repeating unit relative to all repeating units)

[0174] Ultraviolet absorber U1: Tinuvin (registered trademark) 479-DW (manufactured by BASF) Ultraviolet absorber U1 is an aqueous dispersion of particles containing an ultraviolet absorber.

[0175] Photopolymerization initiator

[0176] [Formation of Optically Anisotropic Layer] The first coating film prepared above was subjected to a continuous rubbing treatment. At this time, the longitudinal direction of the long film was parallel to the transport direction, and the angle between the longitudinal direction of the film (transport direction) and the rotation axis of the rubbing roller was 78°. The longitudinal direction of the film (transport 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 the clockwise direction was expressed as a positive value, 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.

[0177] The rubbed cellulose acylate film was used as a support, and a liquid crystal composition L1 containing a rod-shaped liquid crystal compound having the following composition was applied thereto using a Giesser coater to form a composition layer (second coating film). The absolute value of the weighted average helical twisting power of the chiral dopant in the composition layer was 0.0 μm. －１ It was.

[0178] Liquid crystal composition L1 ------------------------------------------------ Rod-shaped liquid crystal compound (A) shown below 80 parts by mass Rod-shaped liquid crystal compound (B) shown below 17 parts by mass Polymerizable compound (C) shown below 3 parts by mass Ethylene oxide modified trimethylolpropane triacrylate (V#360, manufactured by Osaka Organic Chemical Industry Co., Ltd.) 4 parts by mass Photopolymerization initiator (Irgacure 819, manufactured by BASF) 3 parts by mass Left-handed twisted chiral agent (L2) shown below 0.47 parts by mass Right-handed twisted chiral agent (R2) shown below 0.42 parts by mass Polymer (A) shown below 0.08 parts by mass Methyl isobutyl ketone 78 parts by mass Ethyl propionate 78 parts by mass

[0179] Rod-shaped liquid crystal compound (A)

[0180] Rod-shaped liquid crystal compound (B)

[0181] Polymerizable compound (C)

[0182] Left-twisted chiral agent (L2)

[0183] Right-twisted chiral agent (R2)

[0184] Polymer (A) (content of repeating unit on the left side: 39% by mass, content of repeating unit on the right side: 61% by mass)

[0185] Next, the obtained composition layer was heated at 95°C for 60 seconds. This heating caused the rod-shaped 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 lamp (manufactured by Acroedge Co., Ltd.) at 30°C in oxygen-containing air (oxygen concentration: approximately 20% by volume). ２ Subsequently, the obtained composition layer was heated at 95°C for 10 seconds. After that, nitrogen purging was performed 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, the optical film with a support used in Example 1 was produced.

[0186] The supported optical film of Example 1 prepared by the above procedure was cut parallel to the rubbing direction, and the optically anisotropic layer was observed in the cross-sectional direction using a polarizing microscope. The thickness of the optically anisotropic layer was 2.7 μm, and the 1.3 μm-thick region (second region) on the support side of the optically anisotropic layer showed homogeneous alignment without a twist angle, while the 1.4 μm-thick region (first region) on the opposite side of the optically anisotropic layer from the support showed a twisted alignment of the liquid crystal compound. The optical properties of the supported optical film of Example 1 were determined using an Axoscan from Axometrics and their analysis software (Multi-Layer Analysis). The product (Δn2d2) of the in-plane refractive index difference Δn2 and the thickness d2 of the second region at a wavelength of 550 nm 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 long length direction was −11° on the support side and −11° on the side contacting the first region. Furthermore, the product (Δn1d1) of the in-plane refractive index difference Δn1 and the thickness d1 of the first region at a wavelength of 550 nm 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 long length direction was −11° on the side contacting the second region and −91° on the air side.

[0187] The supported optical films used in Examples 2 to 5 were produced in the same manner as the supported optical film of Example 1, except that the ultraviolet absorber U1 contained in the composition for forming an alignment film was changed to the ultraviolet absorber shown in the table below. For Example 9, a supported optical film was obtained in the same manner as Example 4, except that the alignment film was formed without performing alkaline saponification treatment. The amount of ultraviolet absorber added in each Example was adjusted so that the content of the ultraviolet absorber U1 was the same as the content of the polymerizable compound P1. The ultraviolet absorbers used in each Example are shown below.

[0188] (Ultraviolet Absorber U2) Tinuvin (registered trademark) 477-DW (manufactured by BASF) Ultraviolet absorber U2 is an aqueous dispersion of particles containing an ultraviolet absorber.

[0189] (Ultraviolet Absorber U3) SE-2915E (manufactured by Taisei Fine Chemical Co., Ltd.) Ultraviolet absorber U3 is an aqueous dispersion of particles containing an ultraviolet absorber.

[0190] (Ultraviolet absorber U4) Ultraviolet absorber U4 was obtained by the following procedure: First, a monomer M-1 having the following structure was synthesized with reference to WO 2019 / 131572.

[0191]

[0192] A 300 mL three-neck flask equipped with a stirring blade, thermometer, condenser, and nitrogen inlet tube was charged with 12.6 g of cyclohexanone and 12.6 g of 1-methoxy-2-propanol and heated to 120°C under a nitrogen stream. A mixed solution of 3.75 g of the above-mentioned monomer M-1, 1.25 g of acrylic acid, 0.74 g of polymerization initiator V-601, and 25.2 g of cyclohexanone was added dropwise to the above contents over 120 minutes. After reacting for 1 hour, a mixed solution of 0.8 g of polymerization initiator V-601 and 1.7 g of cyclohexanone was added, and the reaction was continued for an additional 2 hours to obtain a solution containing a polymer having the following structure. The weight-average molecular weight of the resulting polymer was 7,200, and it was confirmed by NMR that the target compound had been obtained.

[0193]

[0194] Next, 54.8 g of the obtained polymer solution was weighed into a reaction vessel, and 31.8 g of isopropanol and 11.9 mL of a 1 mol / L aqueous NaOH solution were added, and the temperature in the reaction vessel was raised to 80 ° C. Next, 59.0 g of distilled water was added dropwise at a rate of 20 mL / min, and the polymer was dispersed in water. After dispersion, the temperature in the reaction vessel was kept at 80 ° C. under atmospheric pressure for 2 hours, then at 85 ° C. for 2 hours, and then at 90 ° C. for 2 hours. After maintaining the temperature, the pressure in the reaction vessel was reduced, and a total of 74.9 g of isopropanol and distilled water was distilled off, obtaining an aqueous dispersion of ultraviolet absorber U4 with a solids concentration (particle concentration) of 28.0% by mass. The repeating units contained in the polymer contained in ultraviolet absorber U4 and their ratios are as follows.

[0195]

[0196] (UV absorber U5) 12.6 g of cyclohexanone and 12.6 g of 1-methoxy-2-propanol were placed in a 300 mL three-neck flask equipped with a stirring blade, a thermometer, a condenser, and a nitrogen inlet tube, and heated to 120 ° C. under a nitrogen stream. A mixed solution of 3.75 g of the above-mentioned monomer M-1, 1.25 g of acrylic acid, 0.74 g of polymerization initiator V-601, and 25.2 g of cyclohexanone was added dropwise over 120 minutes. After reacting for 1 hour, a mixed solution of 0.8 g of V-601 and 1.7 g of cyclohexanone was added, and the reaction was continued for an additional 2 hours. After the reaction, the reaction solution was added dropwise to a large excess of hexane, and the precipitated polymer solid was collected and air-dried at 60 ° C., yielding 4.46 g of polymer solid. To the obtained polymer solid, 0.50 g of glycidyl methacrylate, 0.24 g of tetrabutylammonium bromide, 0.2 g of methylhydroquinone, and 50 mL of tetrahydrofuran were added and dissolved, and the mixture was allowed to react at 80 ° C for 8 hours. The weight average molecular weight of the polymer was 9800, and it was confirmed by NMR that the target compound had been obtained. Using the obtained polymer solution, an aqueous dispersion of UV absorber U5 was obtained using the same procedure as for UV absorber U4. The repeating units contained in the polymer contained in UV absorber U5 and their ratios are as follows:

[0197]

[0198] The supported optical film used in Example 6 was obtained in the same manner as the supported optical film used in Example 1, except that the first coating film was formed on a cellulose acylate film that had not been subjected to alkaline saponification treatment using the following procedure.

[0199] (Formation of first coating film) 100 parts by mass of polymerizable compound P2, 0.80 parts by mass of a photoacid generator represented by the following structural formula, and 5.0 parts by mass of ultraviolet absorber U6 were added to 1-methoxy-2-propanol (1,136 parts by mass) to prepare a composition O6 for forming an alignment film.

[0200] -Polymerizable Compound P2- Polymerizable compound P2 was synthesized with reference to WO 2019 / 225632, and was a polymerizable compound having the following repeating units. Note that the ratio of the following repeating units is a mass ratio.

[0201]

[0202] Photoacid generator

[0203] -Ultraviolet Absorber U6- 12.6 g of cyclohexanone and 12.6 g of 1-methoxy-2-propanol were placed in a 300 mL three-neck flask equipped with a stirring blade, thermometer, condenser, and nitrogen inlet tube, and heated to 120°C under a nitrogen stream. A mixed solution of 5.00 g of monomer M-1, 0.30 g of polymerization initiator V-601, and 25.2 g of cyclohexanone was added dropwise over 120 minutes. After reacting for 1 hour, a mixed solution of 0.4 g of V-601 and 1.7 g of cyclohexanone was added, and the mixture was allowed to react for an additional 2 hours, yielding a polymer with the following structure. The weight-average molecular weight of the polymer was 110,000, and it was confirmed by NMR that the target compound had been obtained.

[0204]

[0205] Next, 15 parts by mass of the above polymer was added to a solution prepared by dissolving 7 parts by mass of a dispersant (Hinoact Series T-8000, manufactured by Kawaken Fine Chemicals Co., Ltd.) in 60 parts by mass of 1-methoxy-2-propanol. The solution containing the polymer was dispersed for 72 hours using a ball mill. After dispersion, 75 parts by mass of 1-methoxy-2-propanol was added to the dispersion, and the dispersion was further dispersed for 5 hours using a ball mill. The resulting solution was diluted to a desired solids concentration, yielding a dispersion of ultraviolet absorber U6.

[0206] The prepared composition O6 for forming an alignment film was applied to one side of a cellulose acylate film using a bar coater. After application, the film was dried on a hot plate at 123°C for 62 seconds to remove the solvent, and then irradiated with ultraviolet light (300 mJ / cm ２ The resulting first coating film was irradiated with polarized ultraviolet light (7.9 mJ / cm 2 ). ２ A photo-alignment film was formed by using a super-high pressure mercury lamp.

[0207] The supported optical film used in Example 7 was obtained in the same manner as the supported optical film used in Example 1, except that the first coating film was formed on a cellulose acylate film that had not been subjected to alkaline saponification treatment using the following procedure.

[0208] (Formation of first coating film) 100 parts by mass of polymerizable compound P3, 0.80 parts by mass of a thermal acid generator represented by the following structural formula, and 5.0 parts by mass of ultraviolet absorber U6 were added to 1-methoxy-2-propanol (1,136 parts by mass) to prepare a composition O7 for forming an alignment film.

[0209] —Polymerizable Compound P3— A polymerizable compound having the following repeating units was synthesized with reference to WO 2019 / 225632. The ratio of the following repeating units is a mass ratio.

[0210]

[0211] Thermal Acid Generator

[0212] The prepared composition O7 for forming an alignment film was applied to one side of a cellulose acylate film using a bar coater. After application, the film was dried on a hot plate at 80°C for 5 minutes to remove the solvent, and a first coating film having a thickness of 0.5 µm was formed. The obtained first coating film was irradiated with polarized ultraviolet light (10 mJ / cm ２ A photo-alignment film was formed by using a super-high pressure mercury lamp.

[0213] The supported optical films used in Examples 8 and 10 were prepared in the same manner as the supported optical film of Example 7, except that compositions for forming alignment films were used in which the ultraviolet absorber U6 was replaced with an ultraviolet absorber shown in the table below. The amount of ultraviolet absorber added in Examples 8 and 10 was adjusted to be the same as the content of the ultraviolet absorber U6 relative to the content of the polymerizable compound P3.

[0214] (Ultraviolet absorber U7) A dispersion of ultraviolet absorber U7 was obtained in the same manner as for ultraviolet absorber U6, except that the first dispersion time using a ball mill was 48 hours in the procedure for obtaining the dispersion of ultraviolet absorber U6.

[0215] (UV Absorber U8) 25 g of cyclohexanone was placed in a 300 mL three-neck flask equipped with a stirring blade, thermometer, condenser, and nitrogen inlet tube, and heated to 120°C under a nitrogen stream. A mixed solution of 4.75 g of the above-mentioned monomer M-1, 0.25 g of Cyclomer M100 (manufactured by Daicel Corporation), 0.30 g of polymerization initiator V-601, and 25.2 g of cyclohexanone was added dropwise over 120 minutes. After reacting for 1 hour, a mixed solution of 0.4 g of V-601 and 1.7 g of cyclohexanone was added, and the mixture was allowed to react for an additional 2 hours to obtain a polymer with the following structure. The weight-average molecular weight of the polymer was 12,500, and it was confirmed by NMR that the target compound had been obtained.

[0216] Using the obtained polymer solution, a dispersion of ultraviolet absorber U8 was obtained in the same manner as for ultraviolet absorber U6.

[0217] The supported optical film used in Example 11 was obtained in the same manner as in Example 10, except that the liquid crystal composition L2 shown below was used instead of the liquid crystal composition L1 in forming the optically anisotropic layer.

[0218] Liquid crystal composition L2 ------------------------------------------------ Rod-like liquid crystal compound (D) below: 100 parts by mass Cationic photopolymerization initiator below [CPI-100P (propylene carbonate solution), manufactured by San-Apro Ltd.] 6 parts by mass Left-handed twisted chiral agent (L2) above: 0.47 parts by mass Right-handed twisted chiral agent (R2) above: 0.42 parts by mass Polymer (A) above: 0.08 parts by mass Methyl isobutyl ketone: 78 parts by mass Ethyl propionate: 78 parts by mass

[0219] Rod-shaped liquid crystal compound (D)

[0220] Photocationic polymerization initiator (CPI-100P)

[0221] The supported optical film used in Example 12 was obtained in the same manner as in Example 10, except that polymerizable compound P4 shown below was used instead of polymerizable compound P3.

[0222] Polymerizable compound (P4)

[0223] The supported optical films used in Comparative Examples 1 to 3 were produced in the same manner as the supported optical film of Example 1, except that the ultraviolet absorber U1 contained in the composition for forming an alignment film was changed to one of the ultraviolet absorbers shown in the table below. The amount of ultraviolet absorber added in Comparative Examples 1 to 3 was adjusted so that the content of the ultraviolet absorber U1 relative to the content of the polymerizable compound P1 was the same. The ultraviolet absorbers used in each Comparative Example are shown below.

[0224] (Ultraviolet absorber UC1) A dispersion of ultraviolet absorber UC1 was obtained in the same manner as for ultraviolet absorber U6, except that the first dispersion time using a ball mill was set to 6 hours in the procedure for obtaining the dispersion of ultraviolet absorber U6.

[0225] (Ultraviolet absorber UC2) Tinuvin (registered trademark) 477 (manufactured by BASF)

[0226] The supported optical film used in Comparative Example 4 was produced in the same manner as the supported optical film of Example 1, except that the polymerizable compound contained in the composition for forming an alignment film was changed to polymer PC1 (Kuraray Poval PVA-203).

[0227] The supported optical film used in Comparative Example 5 was produced in the same manner as the supported optical film of Example 1, except that a composition for forming an alignment film that did not contain the ultraviolet absorber U1 was used.

[0228] <Evaluation> Each of the prepared supported optical films was evaluated for the following properties.

[0229] [Orientation] The orientation of the optically anisotropic layer in the supported optical film was evaluated using a polarizing microscope. Specifically, the polarizers of the polarizing microscope were placed in a crossed Nicol position, and the optically anisotropic layer in the supported optical film was observed at 50x magnification. Observation was performed in 10 randomly selected visual fields (visual field size 1715 x 1280 μm), and each visual field was classified into the following three categories. I: No optical defects were observed. II: Slight optical defects were observed, but at a level that poses no practical problems. III: Many optical defects were observed, at a level that poses practical problems. Based on the classification of the 10 visual fields observed, the orientation was evaluated according to the following criteria: A: I or II in all 10 visual fields. B: III was included in 10 visual fields, and the number of III visual fields was 1 to 5. C: III was included in 10 visual fields, and the number of III visual fields was 6 to 10.

[0230] [Adhesion] A cross-cut 100-square test was performed on the optically anisotropic layer of the supported optical film. The supported optical film of Example 9 was once peeled between the support and the alignment film, and then adhered with an adhesive (Aron Alpha 221F, manufactured by Toa Gosei Co., Ltd.) so that the alignment film and the support faced each other. The adhesive tape used in the peel test was Cellotape (registered trademark), and the peel test was performed three times. After the peel test, the number of squares from which more than half of the area had peeled was counted and evaluated according to the following criteria. AA: 0 or more but less than 5 squares peeled off A: 5 or more but less than 10 squares peeled off B: 10 or more but less than 30 squares peeled off C: 30 or more but less than 50 squares peeled off D: 50 or more squares peeled off Note that in the cross-cut test, the support side of the part where peeling occurred was cut with a microtome to expose the cross section, and the cross section was observed with a scanning electron microscope. As a result, in all of the supported optical films for which adhesion was evaluated, the alignment film remained on the support side. Therefore, it can be said that the peeling position when peeling occurred in the adhesion evaluation was not between the support and the alignment film.

[0231] [UV Absorbency] The UV absorbency of the supported optical film was evaluated using a spectrophotometer. Specifically, the transmittance of the supported optical film at a wavelength of 380 nm was measured using a spectrophotometer UV3150 (manufactured by Shimadzu Corporation). Based on the obtained transmittance, the UV absorbency was evaluated according to the following criteria: A: Less than 65% B: 65% or more but less than 75% C: 75% or more but less than 85% D: 85% or more

[0232] <Results> The compositions for forming an alignment film used in producing each supported optical film and the evaluation results of the produced supported optical films are shown in Table 1. In Table 1, the particle size is the value obtained by the method described above. In Table 1, the "maximum absorption wavelength" column for the ultraviolet absorber is classified as follows based on the maximum absorption wavelength of the ultraviolet absorber evaluated by the method described above. A: The maximum absorption wavelength is 360 to 400 nm. B: The maximum absorption wavelength is 320 nm or more and less than 360 nm.

[0233]

[0234] The results in Table 1 confirm that the optical film of the present invention has excellent UV absorption properties, excellent alignment of the liquid crystal compound in the optically anisotropic layer, and excellent adhesion between the alignment film and the optically anisotropic layer. On the other hand, in Comparative Example 1, in which the particle diameter was 500 nm or more, the alignment of the liquid crystal compound in the optically anisotropic layer was poor. Furthermore, in Comparative Examples 2 and 3, in which a non-particulate UV absorber was used, adhesion was poor. Furthermore, in Comparative Example 4, in which a compound without a polymerizable group was used, adhesion was poor. Furthermore, in Comparative Example 5, in which no UV absorber was used, UV absorption was poor. Comparisons between Example 5 and Example 4, and between Example 10 and Example 7, confirm that adhesion was superior when the particles had polymerizable groups, and the polymerizable groups of the particles and the polymerizable groups of the polymerizable compound were both radically polymerizable groups, or when the polymerizable groups of the particles and the polymerizable groups of the polymerizable compound were both cationically polymerizable groups. Comparison of Examples 11 and 12 with Example 10 confirmed that the adhesion was superior when the liquid crystal compound had a polymerizable group, and both the polymerizable group of the liquid crystal compound and the polymerizable group of the polymerizable compound were radically polymerizable groups, or when both the polymerizable group of the liquid crystal compound and the polymerizable group of the polymerizable compound were cationically polymerizable groups.

Claims

1. An alignment film and an optically anisotropic layer disposed adjacent to the alignment film, the optically anisotropic layer is formed using a composition containing a liquid crystal compound, the alignment film includes particles including an ultraviolet absorber and a cured product of a polymerizable compound having a polymerizable group, The average particle size of the particles is 500 nm or less, The optical film, wherein the ultraviolet absorber has a maximum absorption wavelength in the range of 320 to 400 nm.

2. 2. The optical film of claim 1, wherein the maximum absorption wavelength is located in the range of 360 to 400 nm.

3. An optical film as described in claim 1 or 2, wherein the ultraviolet absorber is a benzodithiol compound.

4. The liquid crystal compound has a polymerizable group, the polymerizable group of the liquid crystal compound and the polymerizable group of the polymerizable compound are both radical polymerizable groups, 3. The optical film according to claim 1, wherein the polymerizable group of the liquid crystal compound and the polymerizable group of the polymerizable compound are both cationically polymerizable groups.

5. The particles have a polymerizable group, the polymerizable group of the particle and the polymerizable group of the polymerizable compound are both radical polymerizable groups, The optical film according to claim 1 , wherein the polymerizable group of the particle and the polymerizable group of the polymerizable compound are both cationically polymerizable groups.

6. A polarizing plate comprising the optical film according to claim 1 or 2 and a polarizer.

7. The present invention relates to a method for producing a polymerizable composition comprising the steps of: The average particle size of the particles is 500 nm or less, The composition for forming an alignment film, wherein the ultraviolet absorbent has a maximum absorption wavelength in the range of 320 to 400 nm.

8. 8. The composition for forming an alignment film according to claim 7, wherein the maximum absorption wavelength is in the range of 360 to 400 nm.

9. The composition for forming an alignment film described in claim 7 or 8, wherein the ultraviolet absorber is a benzodithiol compound.

10. The particles have a polymerizable group, the polymerizable group of the particle and the polymerizable group of the polymerizable compound are both radical polymerizable groups, 9. The composition for forming an alignment film according to claim 7, wherein the polymerizable group of the particle and the polymerizable group of the polymerizable compound are both cationically polymerizable groups.

11. A process of applying the composition for forming an alignment film according to claim 7 or 8 onto a support to form a first coating film, and subjecting the first coating film to an alignment treatment; applying a composition containing a liquid crystal compound onto the first coating film that has been subjected to the alignment treatment to form a second coating film; a step of subjecting the first coating film and the second coating film to a curing treatment to form an alignment film and an optically anisotropic layer, thereby forming a laminate including the support, the alignment film, and the optically anisotropic layer; a step of bonding the laminate and the polarizer so that the optically anisotropic layer and the polarizer face each other, and peeling the support from the obtained bonded structure to obtain a polarizing plate including the polarizer, the optically anisotropic layer, and the alignment film.