Colored-layer-forming composition, method for producing same, optical film, and display device

Abstract

This colored-layer-forming composition contains a coloring material (A), an active energy ray-curable compound (B), a photopolymerization initiator (C), a radical scavenger (D), a wetting dispersant (E), and a solvent (F). The coloring material (A) includes a coloring material (A1) that has a solubility of not less than 0.001 mass% to less than 1 mass% with respect to the solvent (F). This method for producing a colored-layer-forming composition comprises a step for preparing a coloring material dispersion liquid containing a coloring material (A1), a wetting dispersant (E), and a solvent (F1), and a step for mixing the coloring material dispersion liquid, an active energy ray-curable compound (B), a photopolymerization initiator (C), a radical scavenger (D), and a solvent (F2). The solubility of the coloring material (A1) with respect to the solvent mixture of the solvent (F1) and the solvent (F2) is not less than 0.001 mass% to less than 1 mass%.

Description

Colored layer-forming composition, method for producing the same, optical film, and display device

[0001] The present invention relates to a colored layer-forming composition, a method for producing the same, an optical film, and a display device. This application claims priority based on Japanese Patent Application No. 2024-098211, filed on June 18, 2024, the contents of which are incorporated herein by reference.

[0002] Generally, electrodes and many other metal wirings of an organic light emitting display device reflect external light (external light), resulting in poor black display and contrast of the organic light emitting display device. One method for suppressing external light reflection is to place a polarizer and a phase retarder on the organic light emitting device. However, this method has a problem in that a significant portion of the light generated from the organic light emitting device is lost when it passes through the polarizer and the phase retarder and is emitted to the outside.

[0003] Therefore, by selectively absorbing external light for each wavelength band and adjusting the transmittance, it is possible to suppress reflection of external light, thereby improving visibility and minimizing the loss of light emitted from the organic light-emitting element to the outside. Patent Document 1 discloses an organic light-emitting display device including a display substrate including organic light-emitting elements and an encapsulation substrate spaced apart from the display substrate, in which a pigment is embedded in the space between the display substrate and the encapsulation substrate to selectively absorb external light for each wavelength band and adjust the transmittance. Patent Document 2 discloses a configuration in which colorants having absorption maxima in at least the wavelength ranges of 470 to 510 nm, 560 to 620 nm, and 650 to 780 nm are contained to improve color purity and improve RGB color separation. Patent Document 3 discloses a configuration in which a wavelength-selective absorption layer containing four dyes having main absorption wavelength bands in specific wavelength ranges is incorporated with an anti-fading agent, and a gas barrier layer is directly disposed on at least one side of the wavelength-selective absorption layer to ensure the reliability of the colorants.

[0004] On the other hand, Patent Document 4 discloses a hard coat resin composition in which a negative infrared absorber containing an aggregate of a diimonium salt compound, which is a near-infrared absorbing dye, is dispersed in an active energy ray-curable resin.

[0005] Japanese Patent No. 5673713 Japanese Patent No. 7088352 International Publication No. 2021 / 066082 Japanese Patent No. 5235762

[0006] As in Patent Documents 2 and 3, when forming a colored layer (wavelength-selective absorption layer) containing a dye with wavelength-selective absorption properties, the dye must usually be dissolved in the solvent of the colored layer-forming composition. Dyes with low solubility in the solvent of the colored layer-forming composition may be difficult to use, even if they have good reliability and optical properties. When using a pigment as in Patent Document 1, the pigment has a wider half-width than the dye, making it prone to loss of light emission from the display device. Furthermore, a method is known in which a dispersant is used to disperse a solvent-insoluble pigment into an ink. However, when applying this method to the formation of a colored layer, the pigment must be finely divided to sufficiently reduce the haze value, which can be time-consuming. Patent Document 4 uses a diimonium salt compound, a near-infrared absorbing dye, in a fine particle dispersion state. However, because the diimonium salt compound has a wide absorption half-width in the fine particle dispersion state and its main absorption wavelength range is longer than the visible light range, it may not be suitable for a colored layer. Furthermore, increasing the concentration of the diimonium salt compound in the hard coat film to obtain sufficient absorption properties may increase the haze value of the film.

[0007] The present invention provides a colored layer-forming composition that can form a colored layer that is excellent in transparency and reliability despite containing a colorant that has low solubility in the solvent of the colored layer-forming composition, a method for producing the same, an optical film having a colored layer that is excellent in transparency and reliability despite containing a colorant that has low solubility in the solvent of the colored layer-forming composition, and a display device using the same.

[0008] The present invention has the following aspects: [1] A colored layer-forming composition comprising a colorant (A), an active energy ray-curable compound (B), a photopolymerization initiator (C), a radical scavenger (D), a wetting and dispersing agent (E), and a solvent (F), wherein the colorant (A) contains a colorant (A1) having a solubility in the solvent (F) of 0.001% by mass or more but less than 1% by mass at 20°C. [2] The colored layer-forming composition according to [1], wherein the colorant (A1) contains one or more compounds selected from the group consisting of compounds having either a phthalocyanine structure or a porphyrin structure, and metal complexes thereof. [3] The colored layer-forming composition according to [1] or [2], wherein the colorant (A1) is dissolved in cyclohexanone at a concentration such that the absorbance at the maximum absorption wavelength is 1, and the half-width at the maximum absorption wavelength of the absorption spectrum obtained is 15 to 30 nm. [4] The colored layer-forming composition according to any one of [1] to [3], wherein the solvent (F) contains either cyclohexanone or acetone, or both. [5] The colored layer-forming composition according to [4], wherein the solvent (F) contains cyclohexanone and acetone, and the mass ratio of the acetone to the cyclohexanone is 1:1. [6] A method for producing a colored layer-forming composition, comprising the steps of: preparing a colorant dispersion liquid containing a colorant (A1), a wetting dispersant (B), and a solvent (F1); and mixing the colorant dispersion liquid with an active energy ray-curable compound (C), a photopolymerization initiator (D), a radical scavenger (E), and a solvent (F2), wherein the solubility of the colorant (A1) in a mixed solvent of the solvent (F1) and the solvent (F2) is 0.001 mass % or more and less than 1 mass % at 20°C. [7] The method for producing a colored layer-forming composition according to the above [6], wherein the colorant dispersion has a D50 particle size at 50% cumulative volume in a particle size distribution measured by a dynamic light scattering method of 2000 to 5000 nm. [8] The method for producing a colored layer-forming composition according to the above [6] or [7], wherein the colorant (A1) contains one or more compounds selected from the group consisting of compounds having either a phthalocyanine structure or a porphyrin structure, and metal complexes thereof.[9] A method for producing a colored layer-forming composition according to any one of [6] to [8], wherein the half-width of the maximum absorption wavelength of an absorption spectrum obtained by dissolving the colorant (A1) in cyclohexanone at a concentration such that the absorbance at the maximum absorption wavelength is 1 is 15 to 30 nm.

[10] A method for producing a colored layer-forming composition according to any one of [6] to [9], wherein the solvent (F1) and the solvent (F2) each independently contain either cyclohexanone or acetone, or both.

[11] A method for producing a colored layer-forming composition according to

[10] , wherein the solvent (F1) and the solvent (F2) each independently contain cyclohexanone and acetone, and the mass ratio of the acetone to the cyclohexanone is 1:1.

[12] An optical film comprising a sheet-like transparent substrate and a colored layer formed on a first surface side of the transparent substrate, wherein the colored layer is a cured product of the colored layer-forming composition according to any one of [1] to [5].

[13] The optical film according to

[12] above, having a haze value of 1% or less as measured in accordance with the method described in JIS K 7136:2000.

[14] The optical film according to

[12] or

[13] above, further comprising a functional layer formed on a second surface of the transparent substrate opposite to the first surface or on the colored layer, wherein one or both of the transparent substrate and the functional layer have an ultraviolet ray blocking rate of 85% or more as measured in accordance with the method described in JIS L 1925:2019.

[15] The optical film according to

[14] above, wherein the functional layer has at least one of an antireflection function and an antiglare function.

[16] The optical film according to

[14] or

[15] above, wherein the functional layer has at least one of an antistatic function and an antifouling function.

[17] A display device comprising the optical film according to any one of

[12] to

[16] above.

[0009] According to the present invention, it is possible to provide a colored layer-forming composition that can form a colored layer that has excellent transparency despite containing a colorant that has low solubility in the solvent of the colored layer-forming composition, a method for producing the same, and an optical film having a colored layer that has excellent transparency despite containing a colorant that has low solubility in the solvent of the colored layer-forming composition, and a display device using the same.

[0010] FIG. 1 is a cross-sectional view of an optical film according to one embodiment. FIG. 2 is a cross-sectional view of an optical film according to another embodiment. FIG. 3 is a cross-sectional view of an optical film according to another embodiment. FIG. 4 is a cross-sectional view of an optical film according to another embodiment. FIG. 5 is a cross-sectional view of an optical film according to another embodiment. FIG. 6 is a cross-sectional view of an optical film according to another embodiment. FIG. 7 is a cross-sectional view of an optical film according to another embodiment. FIG. 8 is a graph showing the spectrum of a white display output through an organic EL light source and a color filter in an example. FIG. 9 is a schematic diagram illustrating a method for calculating the reflection characteristics of a display device. FIG. 10 is a graph showing the spectra of red, green, and blue displayed through an organic EL light source and a color filter in an example.

[0011] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In all drawings, even if the embodiments are different, the same or corresponding components are designated by the same reference numerals, and common descriptions will be omitted.

[0012] [Optical Film] An optical film according to one embodiment of the present invention will be described in detail with reference to FIG.

[0013] 1, the optical film 60 includes a sheet-like transparent substrate 62, a colored layer 61 formed on a first surface (lower side in the figure) of the transparent substrate 62, and a functional layer 63 formed on a second surface (upper side in the figure) opposite to the first surface of the transparent substrate 62. That is, the optical film 60 is a laminate in which the colored layer 61, the transparent substrate 62, and the functional layer 63 are laminated in this order.

[0014] The haze value of the optical film 60 is preferably 1% or less, more preferably 0.5% or less, even more preferably 0.1% or less, and may be 0%. When the haze value is equal to or less than the above upper limit, the optical film 60 has excellent transparency and is less likely to experience a decrease in brightness when used in a display device. The haze value is measured in accordance with the method described in JIS K 7136:2000.

[0015] In the optical film 60, one or both of the transparent substrate 62 and the functional layer 63 preferably have an ultraviolet ray shielding rate of 85% or more. The ultraviolet ray shielding rate is more preferably 90% or more, even more preferably 95% or more, and may even be 100%. When the ultraviolet ray shielding rate is equal to or greater than the above lower limit, the light resistance and heat resistance are more excellent. The ultraviolet ray shielding rate is measured in accordance with the method described in JIS L 1925:2019. The ultraviolet ray shielding rate can be adjusted by imparting ultraviolet ray absorption ability to at least one of the transparent substrate 62 and the functional layer 63.

[0016] The thickness of the optical film 60 is, for example, preferably 10 to 140 μm, more preferably 15 to 120 μm, and even more preferably 20 to 100 μm. When the thickness of the optical film 60 is equal to or greater than the above lower limit, the strength of the optical film 60 can be further increased. When the thickness of the optical film 60 is equal to or less than the above upper limit, not only can the optical film 60 be made lighter, but it is also advantageous for reducing the thickness of the display device.

[0017] Each layer constituting the optical film 60 will now be described.

[0018] <<Colored Layer>> The colored layer 61 is a cured product of a colored layer-forming composition. The colored layer-forming composition of this embodiment contains a colorant (A), an active energy ray-curable compound (B), a photopolymerization initiator (C), a radical scavenger (D), a wetting dispersant (E), and a solvent (F).

[0019] The thickness of the colored layer 61 is preferably, for example, 0.5 to 10 μm. When the thickness of the colored layer 61 is equal to or greater than the above-mentioned lower limit, the colorant can be contained without causing abnormalities in the appearance of the colored layer 61, and the light absorption properties of the colorant can improve the reflectivity and color reproducibility. When the thickness of the colored layer 61 is equal to or less than the above-mentioned upper limit, this is advantageous for making the display device thinner. The thickness of the colored layer 61 can be determined by observing a cross section of the optical film 60 in the thickness direction (a cross section viewed from a direction intersecting the thickness direction) with a microscope or the like.

[0020] <Colorant (A)> The colorant (A) contains a colorant (A1) having a solubility in the solvent (F) of 0.001% by mass or more and less than 1% by mass at 20°C. When the solubility of the colorant (A1) is within the above range, the colorant (A1) can be present in a dissolved state in the colored layer-forming composition, making it possible to form a colored layer with low haze and excellent appearance. The closer the solubility of the colorant (A1) is to the above upper limit, the more the colorant (A1) can be present in a dissolved state in the colored layer-forming composition. The solubility of the colorant (A1) is preferably 0.01% by mass or more and less than 1% by mass, and more preferably 0.1% by mass or more and less than 1% by mass.

[0021] The colorant (A1) can be appropriately selected from known colorants having the above solubility. From the viewpoint of optical properties and reliability, the colorant (A1) preferably contains one or more compounds selected from the group consisting of compounds having either a phthalocyanine structure or a porphyrin structure, and metal complexes thereof. The colorant (A1) may contain one or more of these compounds alone or in combination.

[0022] The colorant (A1) preferably has a half-width at the maximum absorption wavelength of 15 to 30 nm, more preferably 15 to 20 nm, in an absorption spectrum obtained by dissolving the colorant (A1) in cyclohexanone at a concentration such that the absorbance at the maximum absorption wavelength is 1. When the half-width is equal to or greater than the above-mentioned lower limit, the effect of suppressing the reflection characteristics with respect to external light is excellent, and when it is equal to or less than the above-mentioned upper limit, the luminance efficiency is less likely to decrease. In the following description, the half-width of the absorption spectrum refers to the full width at half maximum.

[0023] The colorant (A1) has a maximum absorption wavelength in the range of 560 to 620 nm, for example. The colorant (A1) preferably includes one or more of a first colorant having a maximum absorption wavelength in the range of 470 to 530 nm, a second colorant having a maximum absorption wavelength in the range of 560 to 620 nm, and a third colorant having a maximum absorption wavelength in the range of 650 to 780 nm. The first colorant has a maximum absorption wavelength of 470 nm or more, which makes it difficult to reduce the luminance efficiency of blue light emission, and a maximum absorption wavelength of 530 nm or less, which makes it difficult to reduce the luminance efficiency of green light emission. The second colorant has a maximum absorption wavelength of 560 nm or more, which makes it difficult to reduce the luminance efficiency of green light emission, and a maximum absorption wavelength of 620 nm or less, which makes it difficult to reduce the luminance efficiency of red light emission. The third colorant has a maximum absorption wavelength of 650 nm or more, which makes it difficult to reduce the luminance efficiency of red light emission, and a maximum absorption wavelength of 780 nm or less, which provides an excellent effect of suppressing the reflection characteristics of external light.

[0024] The colorant (A) may further contain, as necessary, a colorant other than the colorant (A1). Examples of the other colorant include dyes and pigments other than the colorant (A1). The content of the colorant (A1) can be any proportion relative to the total mass of the colorant (A), and may be 100 mass%.

[0025] The content of the color material (A) is preferably 0.1 to 10 mass %, more preferably 0.1 to 5 mass %, based on the total mass of the solid content of the colored layer-forming composition. When the content of the color material (A) is equal to or greater than the lower limit, the anti-reflection effect is more excellent. When the content of the color material (A) is equal to or less than the upper limit, the transparency is more excellent and the luminance efficiency of the display device is more excellent.

[0026] <Active Energy Ray-Curable Compound (B)> The active energy ray-curable compound (B) is a compound that polymerizes and cures when irradiated with active energy rays such as ultraviolet rays or electron beams. For example, a monofunctional, difunctional, trifunctional or higher functional (meth)acrylate monomer, urethane (meth)acrylate, etc. can be used. Here, "(meth)acrylate" means both or either one of "acrylate" and "methacrylate."

[0027] Examples of the monofunctional (meth)acrylate compound that can be contained in the active energy ray-curable compound (B) include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, glycidyl (meth)acrylate, acryloylmorpholine, N-vinylpyrrolidone, tetrahydrofurfuryl acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Xyl (meth)acrylate, isobornyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phosphate (meth)acrylate, ethylene oxide-modified phosphate (meth)acrylate, phenoxy (meth)acrylate, ethylene oxide Oxide-modified phenoxy (meth)acrylate, propylene oxide-modified phenoxy (meth)acrylate, nonylphenol (meth)acrylate, ethylene oxide-modified nonylphenol (meth)acrylate, propylene oxide-modified nonylphenol (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypropylene glycol (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxypropyl acrylate hydroxy-3-phenoxypropyl (meth)acrylate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hexahydrohydrogen phthalate, 2-(meth)acryloyloxypropyl tetrahydrohydrogen phthalate, dimethylaminoethyl (meth)acrylate, trifluoroethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate,Examples of such acrylates include octafluoropropyl (meth)acrylate and adamantane derivative mono(meth)acrylates (e.g., adamantyl acrylate having a monovalent mono(meth)acrylate derived from 2-adamantane or adamantanediol). Here, "(meth)acryloyl" refers to both or either "acryloyl" or "methacryloyl."

[0028] Examples of bifunctional (meth)acrylate compounds that can be contained in the active energy ray-curable compound (B) include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, ethoxylated hexanediol di(meth)acrylate, propoxylated hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene Examples of di(meth)acrylates include glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethoxylated neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethylene oxide (EO)-modified bisphenol A di(meth)acrylate, and triethylene glycol di(meth)acrylate.

[0029] Examples of trifunctional or higher functional (meth)acrylate compounds that can be contained in the active energy ray-curable compound (B) include tri(meth)acrylates such as trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tris-2-hydroxyethyl isocyanurate tri(meth)acrylate, and glycerin tri(meth)acrylate; trifunctional compounds such as pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, and ditrimethylolpropane tri(meth)acrylate; (Meth)acrylate compounds: tri- or higher functional (meth)acrylate compounds such as pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ditrimethylolpropane penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and ditrimethylolpropane hexa(meth)acrylate; and polyfunctional (meth)acrylate compounds in which a portion of these (meth)acrylates is substituted with an alkyl group or ε-caprolactone.

[0030] Examples of urethane (meth)acrylates that can be contained in the active energy ray-curable compound (B) include those obtained by reacting a polyester polyol with an isocyanate monomer or a prepolymer, and then reacting the resulting product with a (meth)acrylate monomer having a hydroxyl group.

[0031] More specific examples of urethane (meth)acrylates include pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol triacrylate toluene diisocyanate urethane prepolymer, dipentaerythritol pentaacrylate toluene diisocyanate urethane prepolymer, pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer, and dipentaerythritol pentaacrylate isophorone diisocyanate urethane prepolymer.

[0032] The monofunctional, difunctional, trifunctional or higher functional (meth)acrylate monomer, urethane (meth)acrylate, etc. that can be contained in the active energy ray-curable compound (B) may be used alone or in combination of two or more thereof. In addition, they may be partially polymerized oligomers.

[0033] The active energy ray-curable compound (B) preferably contains a compound having only two (meth)acryloyl groups, from the viewpoint of more excellent light resistance. Examples of compounds having only two (meth)acryloyl groups include the above-mentioned bifunctional (meth)acrylate compounds, hexanediol di(meth)acrylate, and tricyclodecane dimethanol di(meth)acrylate. Among the above, compounds having an alicyclic skeleton are preferred, from the viewpoint of more excellent light resistance and heat resistance. Examples of compounds having only two (meth)acryloyl groups and an alicyclic skeleton include tricyclodecane dimethanol di(meth)acrylate. A compound having only two (meth)acryloyl groups may be used in combination with other active energy ray-curable compounds.

[0034] The content of the active energy ray-curable compound (B) is preferably 20 to 80 mass %, more preferably 30 to 70 mass %, relative to the total mass of the color layer-forming composition. When the content of the active energy ray-curable compound (B) is equal to or greater than the above-mentioned lower limit, the effect of inhibiting fading can be further enhanced. When the content of the active energy ray-curable compound (B) is equal to or less than the above-mentioned upper limit, the handleability of the color layer-forming composition can be further improved.

[0035] When the active energy ray-curable compound (B) contains a compound having only two (meth)acryloyl groups, the content of the compound having only two (meth)acryloyl groups is preferably 20 mass% or more, more preferably 40 mass% or more, and may be 100 mass%, relative to the total mass of the active energy ray-curable compound (B), from the viewpoint of more excellent light resistance and adhesion to a substrate.

[0036] <Photopolymerization Initiator (C)> Examples of the photopolymerization initiator (C) include those that generate radicals when irradiated with active energy rays. Examples of the photopolymerization initiator (C) include benzoins (benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether), phenyl ketones [for example, alkyl phenyl ketones such as acetophenones (for example, acetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, and 1,1-dichloroacetophenone) and 2-hydroxy-2-methylpropiophenone; cycloalkyl phenyl ketones such as 1-hydroxycyclohexyl phenyl ketone], aminoacetophenones {2-methyl-1-[4-(methylthio)phenyl ]-2-morpholinoaminopropanone-1, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, etc.}, anthraquinones (anthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 1-chloroanthraquinone, etc.), thioxanthones (2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone, etc.), ketals (acetophenone dimethyl ketal, benzyl dimethyl ketal, etc.), benzophenones (benzophenone, etc.), xanthones, and phosphine oxides (for example, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, etc.). These photopolymerization initiators may be used alone or in combination of two or more.

[0037] The content of the photopolymerization initiator (C) is preferably 0.01 to 20% by mass, and more preferably 0.01 to 5% by mass, relative to the total mass of the solid content of the color layer-forming composition. When the content of the photopolymerization initiator (C) is equal to or greater than the above-mentioned lower limit, the curability is better. When the content of the photopolymerization initiator (C) is equal to or less than the above-mentioned upper limit, unreacted photopolymerization initiator (C) is less likely to remain, and reliability such as heat resistance is better.

[0038] <Radical Scavenger (D)> The radical scavenger (D) captures radicals that occur when the colorant (A) undergoes oxidative degradation, inhibiting autoxidation and preventing dye degradation (fading). The radical scavenger (D) may be any agent that has the ability to capture radicals (radical scavenging ability), and examples thereof include resins having an amine structure. Here, the term "amine structure" refers to a structure in which the hydrogen atom of ammonia is substituted with a hydrocarbon group or an aromatic atomic group. Examples of the amine structure include primary amines, secondary amines, and tertiary amines, and may also be quaternary ammonium cations.

[0039] Examples of resins having an amine structure that can be used as the radical scavenger (D) include resins having a hindered amine structure with a molecular weight of 2000 or more. When the molecular weight of a resin having a hindered amine structure is 2000 or more, a high anti-fading effect can be obtained. This is thought to be because many molecules remain in the colored layer 61, resulting in a sufficient anti-fading effect. The molecular weight of a resin having a hindered amine structure is, for example, about 200,000, but the upper limit is not particularly limited. In this specification, "molecular weight" means the "mass average molecular weight" measured by gel permeation chromatography (GPC) using polystyrene as a standard substance.

[0040] In a preferred embodiment, the radical scavenger (D) is a polymer containing a structural unit represented by the following formula (i):

[0041]

[0042] In the above formula (i), R １２represents a hydrogen atom, a halogen atom, a carboxyl group, a sulfo group, a cyano group, a hydroxy group, an alkyl group having 10 or less carbon atoms, an alkoxycarbonyl group having 10 or less carbon atoms, an alkylsulfonylaminocarbonyl group having 10 or less carbon atoms, an arylsulfonylaminocarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, an acylaminosulfonyl group having 10 or less carbon atoms, an alkoxy group having 10 or less carbon atoms, an alkylthio group having 10 or less carbon atoms, an aryloxy group having 10 or less carbon atoms, a nitro group, an alkoxycarbonyloxy group, an aryloxycarbonyloxy group, an acyloxy group having 10 or less carbon atoms, an acyl group having 10 or less carbon atoms, a carbamoyl group, a sulfamoyl group, an aryl group having 10 or less carbon atoms, a substituted amino group, a substituted ureido group, a substituted phosphono group or a heterocyclic group; R １３ represents a hydrogen atom or an alkyl group having 30 or less carbon atoms, and X represents a single bond, an ester group, an aliphatic alkyl chain having 30 or less carbon atoms, an aromatic chain, a polyethylene glycol chain, or a linking group formed by combining these. １２ , R １３ and X may both contain a spirodioxane ring.

[0043] R １２ R is preferably a hydrogen atom, a hydroxy group, or an alkyl group having 10 or less carbon atoms. The number of carbon atoms in the alkyl group is preferably 1 to 6, and more preferably 1 to 3. １３ is preferably a hydrogen atom or an alkyl group having 10 or less carbon atoms. The number of carbon atoms in the alkyl group is preferably 1 to 6, and more preferably 1 to 3. X is preferably a single bond or an aliphatic alkyl chain having 30 or less carbon atoms. The number of carbon atoms in the aliphatic alkyl chain is preferably 10 or less, preferably 1 to 6, and more preferably 2 to 4.

[0044] In this embodiment, the radical scavenger (D) may contain, as its main component (the component with the largest mass %), a copolymer of the structural unit represented by formula (i) above and a copolymerization component having any of the repeating units described below. By using a copolymer, it is possible to control the compatibility with other components.

[0045] Examples of the repeating unit include (meth)acrylate repeating units, olefin repeating units, halogen atom-containing repeating units, styrene repeating units, vinyl acetate repeating units, and vinyl alcohol repeating units.

[0046] Examples of the (meth)acrylate repeating unit include a repeating unit derived from a (meth)acrylate monomer having a linear or branched alkyl group on the side chain, and a repeating unit derived from a (meth)acrylate monomer having a hydroxyl group on the side chain.

[0047] Examples of the repeating unit derived from a (meth)acrylate monomer having the linear or branched alkyl group on the side chain include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, and isooctyl (meth)acrylate. Examples of monomer-derived components include octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, myristyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, and octadecyl (meth)acrylate. These may be used alone or in combination of two or more. Among the above, (meth)acrylate-based repeating units having a linear or branched alkyl group having from 1 to 4 carbon atoms in the side chain are preferred.

[0048] Examples of the repeating units derived from (meth)acrylic monomers having a hydroxyl group in the side chain include monomer-derived components such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, and hydroxyphenyl (meth)acrylate. These may be used alone or in combination of two or more.

[0049] Examples of the olefin repeating unit include components derived from olefin monomers such as ethylene, propylene, isoprene, and butadiene. These may be used alone or in combination of two or more.

[0050] Examples of the halogen atom-containing repeating unit include components derived from monomers such as vinyl chloride and vinylidene chloride, which may be used alone or in combination of two or more.

[0051] Examples of styrene-based repeating units include components derived from styrene-based monomers such as styrene, α-methylstyrene, and vinyltoluene. These may be used alone or in combination of two or more. Examples of vinyl acetate-based repeating units include esters of saturated carboxylic acids and vinyl alcohol, such as vinyl acetate and vinyl propionate. These may be used alone or in combination of two or more. Examples of vinyl alcohol-based repeating units include vinyl alcohol, which may have a 1,2-glycol bond in the side chain.

[0052] The copolymer may have any of the structures of a random copolymer, an alternating copolymer, a block copolymer, and a graft copolymer. If the copolymer has a random structure, the manufacturing process and preparation with other components are easy. Therefore, a random copolymer is preferable to other copolymers.

[0053] Radical polymerization can be used as a polymerization method for obtaining the copolymer. Radical polymerization is preferred because it is easy to produce industrially. Radical polymerization may be a solution polymerization method, an emulsion polymerization method, a bulk polymerization method, or a suspension polymerization method. For radical polymerization, it is preferable to use a solution polymerization method. By using a solution polymerization method, it is easy to control the molecular weight of the copolymer.

[0054] In radical polymerization, the above-mentioned monomer may be diluted with a polymerization solvent, and then a polymerization initiator may be added to polymerize the monomer. The polymerization solvent may be, for example, an ester-based solvent, an alcohol ether-based solvent, a ketone-based solvent, an aromatic solvent, an amide-based solvent, or an alcohol-based solvent. The ester-based solvent may be, for example, methyl acetate, ethyl acetate, n-butyl acetate, isobutyl acetate, t-butyl acetate, methyl lactate, or ethyl lactate. The alcohol ether-based solvent may be, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, 3-methoxy-1-butanol, or 3-methoxy-3-methyl-1-butanol. The ketone-based solvent may be, for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, or cyclohexanone. The aromatic solvent may be, for example, benzene, toluene, or xylene. The amide solvent may be, for example, formamide or dimethylformamide. The alcohol solvent may be, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, s-butanol, t-butanol, diacetone alcohol, or 2-methyl-2-butanol. The above-mentioned polymerization solvents may be used alone or in combination of two or more.

[0055] The radical polymerization initiator may be, for example, a peroxide or an azo compound. The peroxide may be, for example, benzoyl peroxide, t-butyl peroxyacetate, t-butyl peroxybenzoate, or di-t-butyl peroxide. The azo compound may be, for example, azobisisobutyronitrile, azobisamidinopropane salt, azobiscyanovaleric acid (salt), or 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide].

[0056] The amount of radical polymerization initiator used is preferably 0.0001 parts by mass or more and 20 parts by mass or less, more preferably 0.001 parts by mass or more and 15 parts by mass or less, and even more preferably 0.005 parts by mass or more and 10 parts by mass or less, when the total amount of monomers is set to 100 parts by mass. The radical polymerization initiator may be added to the monomers and polymerization solvent before the start of polymerization, or may be added dropwise to the polymerization reaction system. Adding the radical polymerization initiator dropwise to the monomers and polymerization solvent in the polymerization reaction system is preferred because it can suppress heat generation due to polymerization.

[0057] The reaction temperature for the radical polymerization is appropriately selected depending on the types of radical polymerization initiator and polymerization solvent. From the viewpoints of ease of production and reaction controllability, the reaction temperature is preferably 60° C. or higher and 110° C. or lower.

[0058] When the radical scavenger (D) is a polymer containing a structural unit represented by formula (i), the content of the structural unit represented by formula (i) is preferably 1 to 95 mol %, and more preferably 10 to 90 mol %, based on the total molar amount of the monomers constituting the radical scavenger (D). When the content of the structural unit represented by formula (i) is within the above range, the light fastness and heat resistance of the colorant (A) are improved, and fading is easily suppressed.

[0059] The content of the radical scavenger (D) is preferably 0.01 to 20 mass %, more preferably 0.01 to 5 mass %, relative to the total mass of the solid content of the color layer-forming composition. When the content of the radical scavenger (D) is equal to or greater than the above-mentioned lower limit, the curability is more excellent. When the content of the radical scavenger (D) is equal to or less than the above-mentioned upper limit, the reliability of light resistance, heat resistance, etc. is more excellent.

[0060] <Wetting Dispersant (E)> The colorant (A) can be dissolved in the solvent (F) by including a wetting dispersant (E) in the colored layer-forming composition. The wetting dispersant (E) has a structure including a portion with high affinity to the dispersoid and a portion with high affinity to the dispersion medium. The presence of the wetting dispersant (E) improves the surface wettability of the colorant (A1), which is thought to facilitate the transition of the colorant (A1) to a dissolved state when the colorant (A1) or a colorant dispersion in which the colorant (A1) has been previously dispersed in a solvent is mixed with other components to prepare the colored layer-forming composition. In the absence of the wetting dispersant (E), the colorant (A) does not dissolve in the solvent (F) in the colored layer-forming composition and remains dispersed, resulting in increased haze in the colored layer and granular appearance. Blending the colorant (A) finely divided like a pigment improves haze and appearance, but the improvement is insufficient and requires more effort than using a highly soluble colorant. The wetting and dispersing agent (E) is generally used to uniformly disperse solid particles (e.g., pigments) that are insoluble in the liquid, and is not usually combined with a coloring material (dye) that is soluble in a solvent.

[0061] The wetting and dispersing agent (E) is not particularly limited and can be appropriately selected from known wetting and dispersing agents. Examples of the wetting and dispersing agent (E) include DISPERBYK-2014 (manufactured by BYK), DISPERBYK-2013 (manufactured by BYK), and DISPERBYK-2200 (manufactured by BYK). One type of wetting and dispersing agent (E) may be used alone, or two or more types may be used in combination.

[0062] The content of the wetting dispersant (E) is preferably 0.5 to 100% by mass, and more preferably 30 to 100% by mass, based on the solid content of the colorant (A1). When the content of the wetting dispersant (E) is equal to or greater than the above-mentioned lower limit, the colorant (A) is likely to be dissolved in the solvent (F) in the colored layer-forming composition. When the content of the wetting dispersant (E) is equal to or less than the above-mentioned upper limit, the handleability of the colorant dispersion liquid is superior.

[0063] <Solvent (F)> Examples of the solvent (F) include ethers, ketones, esters, and cellosolves. Examples of ethers include dibutyl ether, dimethoxymethane, dimethoxyethane, diethoxyethane, propylene oxide, 1,4-dioxane, 1,3-dioxolane, 1,3,5-trioxane, tetrahydrofuran, anisole, and phenetole. Examples of ketones include acetone, methyl ethyl ketone, diethyl ketone, dipropyl ketone, diisobutyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, and ethylcyclohexanone. Examples of esters include ethyl formate, propyl formate, n-pentyl formate, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, n-pentyl acetate, and γ-butyrolactone. Examples of cellosolves include methyl cellosolve, cellosolve (ethyl cellosolve), butyl cellosolve, and cellosolve acetate. The solvent (F) may be used alone or in combination of two or more.

[0064] The solvent (F) preferably contains either or both of cyclohexanone and acetone, and more preferably both of cyclohexanone and acetone. When the solvent (F) contains either or both of cyclohexanone and acetone, the solubility of the colorant and the dispersion stability of the pigment dispersion are excellent. Because cyclohexanone has relatively low volatility, when the solvent (F) contains cyclohexanone, composition fluctuations due to volatilization during storage can be suppressed. Cyclohexanone is suitable as the solvent (F1) for dispersing the colorant (A1) in advance to prepare a colorant dispersion in the manufacturing method for a colored layer-forming composition described below. When the solvent (F) contains acetone, it is advantageous for adhesion to the substrate.

[0065] The total content of cyclohexanone and acetone in solvent (F) is preferably 50% by mass or more, more preferably 70% by mass or more, and may even be 100% by mass, relative to the total mass of solvent (F). The mass ratio of acetone / cyclohexanone in solvent (F) is preferably 30 / 70 to 100 / 0, more preferably 40 / 60 to 70 / 30.

[0066] The content of the solvent (F) is preferably 20 to 80% by mass, more preferably 30 to 60% by mass, relative to the total mass of the colored layer-forming composition. If the content of the solvent (F) is equal to or greater than the lower limit, the colorant (A) in the colored layer-forming composition is likely to be dissolved in the solvent (F). If the content of the solvent (F) is equal to or less than the upper limit, the time required to form the colored layer can be shortened.

[0067] <Additives> The color layer-forming composition may contain additives other than those described above. The color layer-forming composition may contain, for example, one or more compounds selected from the group consisting of sulfur-based antioxidants and compounds represented by the following formula (ii) (hereinafter referred to as "compound A"). By containing one or more compounds selected from the group consisting of sulfur-based antioxidants and compound A, the light resistance and heat resistance of the color material (A) are improved.

[0068]

[0069] In formula (ii), R １are each independently an alkyl group, an alkenyl group, an aryl group, a heterocyclic group, or R ９ CO － , R １０ SO ２ － Or R １１ NHCO － R represents a group represented by ９ , R １０ and R １１ each independently represents an alkyl group, an alkenyl group, an aryl group, or a heterocyclic group; R ２ and R ３ each independently represents a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkoxy group, or an alkenyloxy group; R ４ , R ５ , R ６ , R ７ and R ８ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an aryl group.

[0070] Examples of sulfur-based antioxidants include dialkyldithiophosphates, dialkyldithiocarbamate, benzenedithiol, and transition metal complexes thereof. These compounds may be used alone or in combination of two or more.

[0071] When the color layer-forming composition contains one or more compounds selected from the group consisting of sulfur-based antioxidants and compound A, the total content of the sulfur-based antioxidant and compound A is preferably 0.1 to 15 mass %, more preferably 0.1 to 10 mass %, based on the total mass of the solids in the color layer-forming composition. When the content is equal to or greater than the lower limit, the color material (A) is more likely to exhibit a fading-inhibiting effect in terms of light resistance and heat resistance. When the content is equal to or less than the upper limit, the color layer-forming composition has better curability.

[0072] The color layer-forming composition may contain other additives such as a leveling agent, an antifoaming agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a photosensitizer, and a conductive material.

[0073] <Method for producing a colored layer-forming composition> A method for producing a colored layer-forming composition preferably includes the steps of preparing a colored material dispersion containing a colored material (A1), a wetting dispersant (E), and a solvent (F1) (colored material dispersion preparation step), and mixing the colored material dispersion with an active energy ray-curable compound (B), a photopolymerization initiator (C), a radical scavenger (D), and a solvent (F2) (mixing step). In this case, the mixed solvent of solvents (F1) and (F2) corresponds to solvent (F). In the colored material dispersion, the colored material (A1) is dispersed in solvent (F1). In the subsequent mixing step, the concentration of the colored material (A1) decreases, and most of the colored material (A1) changes from a dispersed state to a dissolved state. All components may be mixed at once, but the colored material (A1) can be easily dissolved by dispersing the colored material (A1) in solvent (F1) in advance in the presence of a wetting dispersant (E).

[0074] (Colorant Dispersion Liquid Preparation Step) The colorant dispersion liquid can be prepared by mixing the colorant (A1), the wetting dispersant (E), and the solvent (F1). At this time, other colorants, additives, etc. may be mixed.

[0075] The solvent (F1) constitutes a part of the solvent (F). Examples of the solvent (F1) include the same solvents as the solvent (F). The mixing method is not particularly limited, and examples thereof include methods using a mixing means such as a rocking shaker or an ultrasonic disperser.

[0076] In the colorant dispersion, the D50 particle size at which the cumulative volume reaches 50% in the particle size distribution measured by dynamic light scattering is preferably 2000 to 5000 nm, and more preferably 2000 to 3000 nm. When the D50 particle size is within the above range, the desired D50 particle size can be easily obtained by a simple mixing operation, and a stable dispersion state can be easily obtained because particle aggregation is suppressed.

[0077] In the colorant dispersion, the content of the colorant (A1) is preferably 3 to 15% by mass, and more preferably 5 to 10% by mass, based on the total mass of the colorant dispersion. The content of the wetting dispersant (E) is preferably 0.5 to 100% by mass, and more preferably 30 to 100% by mass, based on the solid content of the colorant (A1). The content of the solvent (F1) is preferably 70 to 95% by mass, and more preferably 85 to 95% by mass, based on the total mass of the colorant dispersion.

[0078] (Mixing step) The colorant dispersion, the active energy ray curable compound (B), the photopolymerization initiator (C), the radical scavenger (D), and the solvent (F2) are mixed to obtain a colored layer forming composition. At this time, other colorants, additives, etc. may be mixed.

[0079] The solvent (F2) and the solvent (F1) constitute the solvent (F). Examples of the solvent (F2) include the same solvents as those used for the solvent (F). The solvents (F1) and (F2) may be the same or different.

[0080] <Transparent Substrate> The transparent substrate 62 is a sheet-like member that forms the optical film 60. Examples of materials for forming the transparent substrate 62 include transparent resins and inorganic glass. Examples of transparent resins include polyolefins, polyesters, polyacrylates, polyamides, polyimides, polyarylates, polycarbonates, triacetyl cellulose, polyvinyl alcohol, polyvinyl chloride, cycloolefin copolymers, norbornene-containing resins, polyether sulfones, and polysulfones. Examples of polyolefins include polyethylene and polypropylene. Examples of polyesters include polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate. Examples of polyacrylates include polymethyl methacrylate. Examples of polyamides include nylon 6 and nylon 66. Among these, films made of polyethylene terephthalate (PET), films made of triacetyl cellulose (TAC), films made of polymethyl methacrylate (PMMA), and films made of polyesters other than PET are preferred. The thickness of the transparent substrate 62 is not particularly limited, but is preferably 10 to 100 μm, for example. The total light transmittance of the transparent substrate 62 is preferably 90% or more, for example.

[0081] The transparent substrate 62 may be provided with ultraviolet absorbing ability. By adding an ultraviolet absorbing agent to the resin that is the raw material of the transparent substrate 62, the transparent substrate 62 can be provided with ultraviolet absorbing ability.

[0082] Examples of the ultraviolet absorber include salicylic acid ester-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, benzotriazine-based ultraviolet absorbers, and cyanoacrylate-based ultraviolet absorbers. These ultraviolet absorbers may be used alone or in combination of two or more.

[0083] When the transparent substrate 62 is provided with ultraviolet absorbing ability, the ultraviolet shielding rate of the transparent substrate 62 is preferably 85% or more. When the ultraviolet shielding rate is 85% or more, the effect of suppressing fading of the colorant (A) due to its optical properties is more excellent. The ultraviolet shielding rate is a value measured in accordance with JIS L 1925:2019, and is calculated by the following formula: ultraviolet shielding rate (%) = 100 - average transmittance (%) of ultraviolet light with a wavelength of 290 to 400 nm.

[0084] <<Functional Layer>> The optical film 60 can exhibit various functions by including the functional layer 63. Examples of the functions of the functional layer 63 include an anti-reflection function, an anti-glare function, an anti-static function, an anti-fouling function, a reinforcement function, and an ultraviolet absorbing function (ultraviolet absorbing ability). The functional layer 63 may be a single layer or may have multiple layers. The functional layer 63 may have one type of function or two or more types of functions.

[0085] When the optical film 60 has an anti-reflection function, the functional layer 63 functions as an anti-reflection layer. An example of the anti-reflection layer is a low refractive index layer that exhibits a lower refractive index than the transparent substrate 62, the hard coat layer, or the anti-glare layer described below. The low refractive index layer can be formed by using a material for the functional layer that has a lower refractive index than the materials of the transparent substrate 62, the hard coat layer, or the anti-glare layer. In order to adjust the refractive index of the low refractive index layer, lithium fluoride (LiF), magnesium fluoride (MgF ２ ), sodium hexafluoroaluminum (cryolite, cryolite, 3NaF·AlF ３ , Na ３ AlF ６ ), aluminum fluoride (AlF ３ ), silica fine particles, etc. may be blended. As the silica fine particles, the use of porous silica fine particles or hollow silica fine particles having voids inside the particles is effective in lowering the refractive index of the low refractive index layer. Furthermore, the composition for forming the low refractive index layer (composition for forming the low refractive index layer) may be appropriately blended with the photopolymerization initiator (C), solvent, and additives described in the colored layer. The refractive index of the low refractive index layer is preferably 1.20 to 1.55. The thickness of the low refractive index layer is not particularly limited, but is preferably 40 nm to 1 μm, for example.

[0086] When the optical film 60 has an anti-glare function, the functional layer 63 functions as an anti-glare layer. The anti-glare layer has fine irregularities on its surface, which scatter external light and reduce glare, improving display quality. When combined with a low refractive index layer, the low refractive index layer and the anti-glare layer form an anti-reflection layer. The anti-glare layer optionally contains one or more organic or inorganic fine particles. The organic fine particles are materials that form fine irregularities on the surface and impart the function of scattering external light. Examples of organic fine particles include resin particles made of translucent resin materials such as acrylic resin, polystyrene resin, styrene-(meth)acrylic acid ester copolymer, polyethylene resin, epoxy resin, silicone resin, polyvinylidene fluoride, and polyethylene fluoride resin. Two or more types of resin particles with different refractive indices may be mixed to adjust the refractive index and dispersibility of the resin particles. The inorganic fine particles are materials that adjust the sedimentation and aggregation of the organic fine particles. Examples of inorganic fine particles include silica fine particles, metal oxide fine particles, and various mineral fine particles. Examples of silica fine particles include colloidal silica and silica fine particles surface-modified with reactive functional groups such as (meth)acryloyl groups. Examples of metal oxide fine particles include alumina (aluminum oxide), zinc oxide, tin oxide, antimony oxide, indium oxide, titania (titanium dioxide), and zirconia (zirconium dioxide). Examples of mineral fine particles include mica, synthetic mica, vermiculite, montmorillonite, iron-montmorillonite, bentonite, beidellite, saponite, hectorite, stevensite, nontronite, magadiite, ilealite, kanemite, layered titanic acid, smectite, and synthetic smectite. Mineral fine particles may be either natural or synthetic (including substituted or derivative) materials, or a mixture of both may be used. Among mineral fine particles, layered organic clays are more preferred. The layered organic clay refers to a swelling clay in which organic onium ions are introduced between the layers. The organic onium ions are not limited as long as they can be organized by utilizing the cation exchange properties of the swelling clay.When a layered organic clay mineral is used as the mineral fine particles, the above-mentioned synthetic smectite can be preferably used. The synthetic smectite has the function of increasing the viscosity of the coating liquid for forming the antiglare layer, suppressing the settling of the resin particles and inorganic fine particles, and adjusting the uneven shape of the surface of the antiglare layer (functional layer 63).

[0087] When the optical film 60 has an antistatic function, the functional layer 63 functions as an antistatic layer. Examples of the antistatic layer include a layer containing metal oxide fine particles such as antimony-doped tin oxide (ATO) and tin-doped indium oxide (ITO), a polymeric conductive composition, and an antistatic agent such as a quaternary ammonium salt. When the functional layer 63 has multiple layers, the antistatic layer may be provided on the outermost surface of the functional layer 63, or may be provided between another functional layer and the transparent substrate 62. The antistatic layer may be formed by blending an antistatic agent into any of the layers constituting the functional layer 63. When an antistatic layer is provided, the surface resistance of the optical film 60 is 1.0×10 ６ ~1.0 x 10 １２ (Ω / cm).

[0088] When the optical film 60 has an anti-fouling function, the functional layer 63 functions as an anti-fouling layer. The anti-fouling layer enhances the anti-fouling properties by imparting water repellency and / or oil repellency. Examples of the anti-fouling layer include a layer containing an anti-fouling agent such as silicon oxide, a fluorine-containing silane compound, a fluoroalkylsilazane, a fluoroalkylsilane, a fluorine-containing silicon compound, or a perfluoropolyether group-containing silane coupling agent. When the functional layer 63 has multiple layers, the anti-fouling layer may be provided on the outermost surface of the functional layer 63, or the anti-fouling layer may be formed by incorporating an anti-fouling agent into the outermost layer of the functional layer 63.

[0089] When the optical film 60 has a reinforcing function, the functional layer 63 functions as a reinforcing layer. The reinforcing layer is a layer that increases the strength of the optical film. Examples of the reinforcing layer include a hard coat layer. Examples of the hard coat layer include a layer formed of a hard coat agent containing an active energy ray-curable compound such as a monofunctional, difunctional, or trifunctional or higher functional (meth)acrylate or urethane (meth)acrylate, and a photopolymerization initiator. The hard coat agent may contain additives or solvents as necessary.

[0090] When the optical film 60 has ultraviolet absorption capability, the functional layer 63 functions as an ultraviolet absorption layer. Examples of ultraviolet absorption layers include layers containing triazine-based ultraviolet absorbers such as 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxyphenol, and benzotriazole-based ultraviolet absorbers such as 2-(2H-benzotriazol-2-yl)-4-methylphenol. The content of the ultraviolet absorber is preferably 0.1 to 5 mass% relative to the total mass of the materials forming the ultraviolet absorption layer. When the content of the ultraviolet absorber is equal to or greater than the lower limit, sufficient ultraviolet absorption capability can be imparted to the functional layer 63. When the content of the ultraviolet absorber is equal to or less than the upper limit, insufficient hardness due to a decrease in the curing component can be avoided.

[0091] From the viewpoint of suppressing a decrease in visibility due to reflection of external light, the functional layer 63 preferably has at least one of an anti-reflection function and an anti-glare function. From the viewpoint of preventing the generation of static electricity, anti-fingerprint properties, and water and oil repellency, the functional layer 63 preferably has at least one of an anti-static function and an anti-fouling function. The functional layer 63 may have at least one of an anti-static function and an anti-fouling function in combination with at least one of an anti-reflection function and an anti-glare function. It may also have other functions, such as a strengthening function.

[0092] The thickness of the functional layer 63 is, for example, preferably 0.04 to 25 μm, more preferably 0.1 to 20 μm, and even more preferably 0.2 to 15 μm. When the thickness of the functional layer 63 is equal to or greater than the above lower limit, various functions can be easily imparted to the optical film 60. When the thickness of the functional layer 63 is equal to or less than the above upper limit, it is advantageous for reducing the thickness of the display device.

[0093] [Method for Manufacturing Optical Film] The optical film 60 of this embodiment can be manufactured by a conventionally known method. For example, a colored layer-forming composition is applied to one surface of a transparent substrate 62, and the colored layer-forming composition is cured by irradiating it with active energy rays, thereby obtaining the colored layer 61. There are no particular limitations on the method for applying the colored layer-forming composition, and any known application method can be used. Any light source that generates active energy rays can be used as the light source for irradiating the colored layer-forming composition with active energy rays to form the colored layer 61. Examples of light energy rays that can be used include radiation (gamma rays, X-rays, etc.), ultraviolet rays, visible light, and electron beams (EB), and are typically ultraviolet rays or electron beams. For example, lamps that emit ultraviolet rays can be used, such as low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, carbon arc lamps, metal halide lamps, xenon lamps, and electrodeless discharge tubes. Regarding irradiation conditions, the ultraviolet irradiation dose is typically 100 to 1,000 mJ / cm. ２ is.

[0094] Next, a functional layer 63 is formed on the other surface of the transparent substrate 62, thereby obtaining an optical film 60 in which the functional layer 63 is located on the other surface of the transparent substrate 62. The method for forming the functional layer 63 is not limited, and known methods can be used. For example, a method for forming a hard coat layer can be exemplified by applying a hard coat agent to the other surface of the transparent substrate 62 (or on another functional layer) and curing it by irradiating it with active energy rays. Examples of a method for forming a low refractive index layer can be exemplified by applying a composition for forming a low refractive index layer to the other surface of the transparent substrate 62 (or on another functional layer) and curing it by irradiating it with active energy rays, vacuum deposition, sputtering, ion plating, ion beam deposition, plasma vapor deposition, etc.

[0095] 2, the optical film may be an optical film 60A in which a colored layer 61, a transparent substrate 62, a hard coat layer 63b, and a low refractive index layer 63a are laminated in this order. In the optical film 60A, the hard coat layer 63b and the low refractive index layer 63a constitute a functional layer 63. The optical film 60A of this embodiment has excellent reflection suppression due to the inclusion of the low refractive index layer 63a.

[0096] 3, the optical film may be an optical film 60B in which a colored layer 61, a transparent substrate 62, and an antiglare layer 63c are laminated in this order. In the optical film 60B, the antiglare layer 63c constitutes the functional layer 63. The optical film 60B of this embodiment has an excellent antireflection property due to the inclusion of the antiglare layer 63c.

[0097] 4, the optical film may be an optical film 60C in which a colored layer 61, a transparent substrate 62, an antiglare layer 63c, and a low refractive index layer 63a are laminated in this order. In the optical film 60C, the antiglare layer 63c and the low refractive index layer 63a constitute the functional layer 63. The optical film 60C of this embodiment has the low refractive index layer 63a and the antiglare layer 63c, and therefore is superior in antireflection properties.

[0098] 5, the optical film may be an optical film 60D in which a transparent substrate 62, a colored layer 61, a hard coat layer 63b, and a low refractive index layer 63a are laminated in this order. In the optical film 60D, the hard coat layer 63b and the low refractive index layer 63a constitute a functional layer 63. The optical film 60D of this embodiment has the colored layer 61 and the functional layer 63 having an ultraviolet absorbing function and an anti-reflection function on one surface of the transparent substrate 62. The ultraviolet absorbing function may be imparted to any of the layers constituting the functional layer.

[0099] As shown in Fig. 6, the optical film may be an optical film 60E in which a transparent substrate 62, a colored layer 61, and an antiglare layer 63c are laminated in this order. In the optical film 60E, the antiglare layer 63c constitutes the functional layer 63. The optical film 60E of this embodiment has excellent anti-reflection properties due to the inclusion of the antiglare layer 63c. In the optical film 60E, it is preferable to impart an ultraviolet absorbing function to the antiglare layer 63c.

[0100] As shown in Fig. 7, the optical film may be an optical film 60F in which a transparent substrate 62, a colored layer 61, an antiglare layer 63c, and a low refractive index layer 63a are laminated in this order. In the optical film 60F, the antiglare layer 63c and the low refractive index layer 63a constitute the functional layer 63. The optical film 60F of this embodiment has the low refractive index layer 63a and the antiglare layer 63c, and therefore is superior in anti-reflection properties. In the optical film 60F, it is preferable to impart an ultraviolet absorbing function to one of the layers constituting the functional layer 63.

[0101] The optical film according to each of the above-described embodiments has a colored layer that is excellent in transparency and reliability, even though it contains a colorant that has low solubility in the solvent of the colored layer-forming composition. Conventionally, colorants with low solubility in solvents, even if they have excellent optical properties, have not been used in colored layers. In this embodiment, such a colorant can be used as the colorant (A1) to improve optical properties. Furthermore, in this embodiment, the colored layer-forming composition contains a radical scavenger (D), which suppresses deterioration of the colorant (A) in the colored layer due to light or heat, resulting in excellent reliability. In particular, when the layer (either the functional layer or one or both of the transparent substrate) located above the colored layer in the optical film has an ultraviolet shielding rate of 85% or more, reliability is even more excellent.

[0102] Each embodiment of the present invention has been described above in detail with reference to the drawings, but the specific configuration is not limited to this embodiment, and configuration changes, combinations, etc. are also included within the scope that does not deviate from the gist of the present invention.

[0103] For example, although each of the optical films described above has one colored layer, the number of colored layers may be two or more. In the optical film according to each embodiment, the ultraviolet absorbing ability may be imparted to the transparent substrate 62, or to a functional layer 63 such as the hard coat layer 63b. What is important is that when attached to a display device, the ultraviolet absorbing ability is imparted to a layer that is closer to the screen viewed by the user than the colored layer 61. Although each of the optical films described above has a functional layer 63, the optical film does not necessarily have to have the functional layer 63.

[0104] [Display Device] The display device of the present invention includes the optical film of the present invention. Specific examples of the display device include televisions, monitors, mobile phones, portable game devices, personal digital assistants, personal computers, electronic books, video cameras, digital still cameras, head-mounted displays, navigation systems, audio playback devices (car audio, digital audio players, etc.), copiers, facsimiles, printers, multi-function printers, vending machines, automated teller machines (ATMs), personal authentication devices, optical communication devices, and IC cards. Among these, display devices including self-luminous elements such as LEDs, organic electroluminescent devices, inorganic phosphors, and quantum dots are preferred because they are susceptible to the influence of external light reflection due to metal electrodes and wiring, and the application of the present invention is highly useful.

[0105] The present invention will be described in more detail below using examples. The technical scope of the present invention is not limited solely by the specific content of these examples. "Parts" means "parts by mass."

[0106] <Coloring Materials> The following coloring materials were prepared. Dye-1: tetraazaporphyrin copper complex dye (Yamada Chemical Industry Co., Ltd.'s "FDG-025", maximum absorption wavelength 573 nm, half-width 18 nm) Dye-2: phthalocyanine copper complex dye (Yamada Chemical Industry Co., Ltd.'s "FDR-005", maximum absorption wavelength 704 nm, half-width 26 nm) Dye-3: tetraazaporphyrin copper complex dye (Yamada Chemical Industry Co., Ltd.'s "FDG-007", maximum absorption wavelength 595 nm, half-width 22 nm) Pig-1: purple pigment (C.I. Pigment Violet 23, BASF Corporation's "Paliogen Violet 5890") The maximum absorption wavelength and half width of Dye-1, Dye-2, and Dye-3 refer to the maximum absorption wavelength and half width in the absorption spectrum measured for a solution in which Dye-1, Dye-2, or Dye-3 is dissolved in cyclohexanone at a concentration such that the absorbance at the maximum absorption wavelength is 1.

[0107] <Solubility of Colorant> The solubility of the above colorant in cyclohexanone, acetone, and a 50 / 50 (mass ratio) mixed solvent was measured at 20°C. 5 mg of colorant was weighed and placed in a 900 mL glass container with a lid, and 495 mg of solvent was added. The mixture was stirred for 15 minutes, then allowed to stand for 5 minutes. The container was then inverted and visually checked for the presence or absence of residual solvent. If no residual solvent was present, the solubility was recorded as 1% by mass or more. If residual solvent was present, an additional 499.5 g of solvent was added, stirred for 15 minutes, allowed to stand for 5 minutes, and the container was then inverted and visually checked for the presence or absence of residual solvent. If no residual solvent was present, the solubility was recorded as 0.001% by mass or more. If residual solvent was present, the solubility was recorded as less than 0.001% by mass. In this specification, a state in which there is no residual dissolution (dissolved state) refers to, for example, a state in which there is no precipitation of colorant and the particle size distribution of the colorant cannot be measured using a particle size distribution analyzer (i.e., a state in which the colorant is dissolved and not in a dispersed state). A solubility of 1% by mass or more was evaluated as "Good", a solubility of 0.001% by mass or more but less than 1% by mass was evaluated as "Average", and a solubility of less than 0.001% by mass (including cases in which the colorant is not dissolved) was evaluated as "Poor". The results are shown in Table 1.

[0108]

[0109] <Preparation of Colorant Dispersion> Dispersions 1 to 6 were prepared according to the following procedure, and the D50 particle diameter was measured. Table 2 shows the composition and D50 particle diameter of each dispersion.

[0110] (Dispersion 1) 0.18 g of Dye-1, 2.55 g of cyclohexanone, 0.27 g of Dispersant 1 ("DISPERBYK-2014" manufactured by BYK Corporation) as a wetting dispersant, and 10 g of zirconia beads having a particle size of 0.1 mm were added to a 9 mL glass container and shaken for 1 hour using a rocking shaker. Thereafter, the zirconia beads were filtered off using a filter with a pore size of 5 μm to obtain Dispersion 1.

[0111] (Dispersion 2) Dispersion 2 was prepared in the same manner as Dispersion 1, except that Dye-2 was used instead of Dye-1.

[0112] (Dispersion 3) Dispersion 3 was prepared in the same manner as Dispersion 1, except that Dye-3 was used instead of Dye-1.

[0113] (Dispersion 4) 0.18 g of Dye-1, 2.82 g of cyclohexanone, and 10 g of zirconia beads with a particle size of 0.1 mm were added to a 9 mL glass container and shaken for 1 hour using a rocking shaker. Thereafter, the zirconia beads were filtered off using a filter with a pore size of 5 μm to obtain Dispersion 4.

[0114] (Dispersion 5) 9.00 wt % of Pig-1, 5.36 wt % of the pigment derivative represented by the following formula (1), 30.2 wt % of an acrylic resin solution (solid content 12.1%), and 55.5 wt % of propylene glycol monomethyl ether acetate (PGMEA) were uniformly mixed with stirring, and then dispersed for 3 hours in an Eiger mill ("Mini Model M-250MKII" manufactured by Eiger Japan Co., Ltd.) using zirconia beads with a diameter of 1.0 mm. The zirconia beads were then filtered off using a filter with a pore size of 5 μm to obtain Dispersion 5.

[0115]

[0116] (Dispersion 6) A commercially available carbon black dispersion (manufactured by Tokushiki Co., Ltd., "8711 BLACK", dispersion medium: N-methyl-2-pyrrolidone) was used as dispersion 6.

[0117] (Dispersion 7) Dispersion 7 was prepared in the same manner as Dispersion 1, except that Dispersant 2 (manufactured by BYK Corporation, "DISPERBYK-2013") was used instead of Dispersant 1 as the wetting dispersant.

[0118] (Dispersion 8) Dispersion 8 was prepared in the same manner as Dispersion 1, except that Dispersant 3 (manufactured by BYK Corporation, "DISPERBYK-2200") was used instead of Dispersant 1 as the wetting dispersant.

[0119] (Dispersion Particle Size Distribution D50 Particle Diameter) The particle size distribution of the colorant dispersion was measured using a Nanotrac UPA-EX150 particle size distribution analyzer (dynamic light scattering method, Nikkiso Co., Ltd.) to determine the D50 particle diameter at which the cumulative volume reached 50%.

[0120]

[0121] In Table 2, CB represents carbon black. In Dispersion 3, the solubility of the coloring material in cyclohexanone was high, so the coloring material was in a dissolved state and the particle size distribution could not be measured.

[0122] <Preparation of Colored Layer-Forming Composition> Compositions for forming colored layers 1 to 13 were prepared by mixing the materials so as to obtain the compositions shown in Table 3. In the table, the amount added is the proportion (mass %) relative to the total mass of the composition. The ratios are mass ratios. "-" indicates that the component is not contained.

[0123]

[0124] In Table 3, the materials used other than the colorant dispersion and the solvent are as follows: DCPA: dimethylol-tricyclodecane diacrylate DPHA: dipentaerythritol hexaacrylate PETA: pentaerythritol triacrylate UA-306H: UA-306H (pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer) manufactured by Kyoeisha Chemical Co., Ltd. Omnirad TPO: (acylphosphine oxide photopolymerization initiator) manufactured by IGM Resins B.V. Resin 1: a resin represented by the above formula (ii), manufactured in the manufacturing example shown below, where R in the formula １２ is CH ３ , R １３ is CH ３ and a polymer containing a structural unit in which X is a single bond. LA-63P: a hindered amine radical scavenger, "ADEKA STAB (registered trademark) LA-63P" manufactured by ADEKA Corporation.

[0125] (Production Example of Resin 1) 2.4 g of 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate ("FA-711MM" manufactured by Showa Denko Materials Co., Ltd.), 5.6 g of methyl methacrylate (manufactured by Kanto Chemical Co., Ltd.), 31 g of cyclohexanone (manufactured by Kanto Chemical Co., Ltd.), and 0.11 g of 2,2'-azobis(isobutyronitrile) (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) were placed in a reaction vessel and heated with stirring at 70°C for 8 hours under a nitrogen gas atmosphere. Subsequently, the mixture was heated with stirring at 100°C for 1 hour to obtain a polymer solution. This polymer solution was poured into 400 mL of methanol (manufactured by Kanto Chemical Co., Ltd.), and the resulting precipitate was filtered and dried to obtain Resin 1, which was copolymerized with 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate and methyl methacrylate at a ratio of 15:85 [mol %]. Resin 1 had a weight average molecular weight of 120,000.

[0126] <Preparation of Optical Films> Optical films of Examples 1 to 12 and Comparative Examples 1 to 7 were prepared with the layer structures shown in Tables 4 and 5. In the tables, "-" indicates that the corresponding layer was not present. The method for forming each layer will be described below.

[0127]

[0128]

[0129] [Transparent substrate] The following transparent substrates were used: TAC: triacetyl cellulose film (manufactured by Fujifilm Corporation, TG60UL, substrate thickness 60 μm, UV shielding rate 92.9%) PMMA: polymethyl methacrylate film (manufactured by Sumitomo Chemical Co., Ltd., W002N80, substrate thickness 80 μm, UV shielding rate 13.9%)

[0130] [Colored Layer] A colored layer-forming composition corresponding to the colored layer shown in Tables 4 and 5 was applied onto a transparent substrate shown in Tables 4 and 5 so that the film thickness after curing would be 5.0 μm, and the coating was dried in an oven at 80° C. for 60 seconds. Thereafter, an ultraviolet irradiation device was used to apply the coating to the transparent substrate at an irradiation dose of 150 mJ / cm. ２ The coating film was cured by irradiating it with ultraviolet light (H bulb light source, manufactured by Fusion UV Systems Japan Co., Ltd.) to form a colored layer.

[0131] [Hard Coat Layer (Functional Layer)] (Hard Coat Layer Forming Composition) The materials shown below were mixed to obtain the compositions shown in Table 6 to prepare hard coat layer forming compositions for forming hard coat layers 1 and 2. In the table, the amount added is the ratio (mass %) to the total mass of the composition. The ratios are mass ratios. "-" indicates that the component is not contained. - Active energy ray curable compound UA-306H: UA-306H (pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer) manufactured by Kyoeisha Chemical Co., Ltd. DPHA: dipentaerythritol hexaacrylate PETA: pentaerythritol triacrylate - Photopolymerization initiator Omnirad TPO: IGM Resins B.V. (acylphosphine oxide-based photopolymerization initiator) Additives (ultraviolet (UV) absorbers) Tinuvin 479: BASF Japan Ltd., Tinuvin (registered trademark) 479 (hydroxyphenyltriazine-based UV absorber) LA-36: ADEKA Corporation, Adekastab (registered trademark) LA-36 (benzotriazole-based UV absorber) Solvents MEK: methyl ethyl ketone methyl acetate

[0132] (Formation of Hard Coat Layer) A composition for forming a hard coat layer corresponding to the hard coat layer shown in Table 4 or Table 5 was applied onto a transparent substrate or a colored layer shown in Table 4 or Table 5 so that the film thickness after curing would be 5.0 μm, and the composition was dried in an oven at 80° C. for 60 seconds. Thereafter, an ultraviolet irradiation device was used to apply an irradiation dose of 150 mJ / cm ２ The coating was cured by irradiating it with ultraviolet light (H bulb light source, manufactured by Fusion UV Systems Japan Co., Ltd.) to form a hard coat layer.

[0133]

[0134] [Antiglare Layer (Functional Layer)] (Composition for Forming Antiglare Layer) The following materials were mixed to prepare a composition for forming an antiglare layer. Active energy ray curable compound: pentaerythritol triacrylate ("Light Acrylate PE-3A" manufactured by Kyoeisha Chemical Co., Ltd., refractive index 1.52) 43.7 parts Photopolymerization initiator: Omnirad TPO (manufactured by IGM Resins B.V.) 4.55 parts Organic fine particles: styrene-methyl methacrylate copolymer particles (refractive index 1.515, average particle size 2.0 μm) 0.5 parts Inorganic fine particles: synthetic sucmetite 0.25 parts alumina nanoparticles (average particle size 40 nm) 1.0 parts Solvent: toluene 15 parts isopropyl alcohol 35 parts

[0135] (Formation of Antiglare Layer) The composition for forming an antiglare layer was applied to a transparent substrate shown in Table 4 so that the film thickness after curing would be 5.0 μm, and the coating was dried in an oven at 80° C. for 60 seconds. Thereafter, the coating was irradiated with an ultraviolet ray at a dose of 150 mJ / cm using an ultraviolet ray irradiator. ２ The coating film was cured by irradiating it with ultraviolet light using a light source H bulb (manufactured by Fusion UV Systems Japan Co., Ltd.) to form an antiglare layer.

[0136] [Low Refractive Index Layer (Functional Layer)] (Composition for Forming a Low Refractive Index Layer) The following materials were mixed to prepare a composition for forming a low refractive index layer. Refractive index adjuster: porous silica fine particles (average particle size 75 nm, solid content 20%) methyl isobutyl ketone dispersion 8.5 parts Antifouling agent: Optool (registered trademark) AR-110 (manufactured by Daikin Industries, Ltd., solid content 15%, solvent: methyl isobutyl ketone) 5.6 parts Active energy ray curable resin: pentaerythritol triacrylate (PETA) 0.4 parts Photopolymerization initiator: Omnirad TPO (manufactured by IGM Resins B.V.) 0.07 parts Leveling agent: RS-77 (manufactured by DIC Corporation) 1.7 parts Solvent: methyl isobutyl ketone 83.73 parts

[0137] (Formation of Low Refractive Index Layer) The composition for forming a low refractive index layer was applied onto the hard coat layer or antiglare layer shown in Table 4 or Table 5 so that the film thickness after curing would be 100 nm, and the applied composition was dried in an oven at 80°C for 60 seconds. Thereafter, the applied composition was exposed to an irradiation dose of 200 mJ / cm using an ultraviolet irradiation device. ２ The coating film was cured by irradiating it with ultraviolet light (H bulb light source, manufactured by Fusion UV Systems Japan Co., Ltd.) to form a low refractive index layer.

[0138] <Evaluation> The produced optical films were evaluated for optical film properties (light resistance, heat resistance, UV blocking rate on the colored layer, haze, coating film appearance) and display device properties in an organic EL panel (white display transmission properties, display device reflection properties, color reproducibility) by the methods described below. The display device properties were evaluated by simulation. The evaluation results are shown in Tables 7 and 8.

[0139] [Method for Evaluating Optical Film Properties] (Lightfastness) The optical film was subjected to a lightfastness test as a reliability test. The lightfastness test was carried out using a xenon weather meter tester (X75, manufactured by Suga Test Instruments Co., Ltd.) with a xenon lamp illuminance of 60 W / cm ２ The test was carried out under conditions of 45°C (300 nm to 400 nm) and 50% RH humidity for 120 hours. Before and after the test, transmittance was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.), and the transmittance difference ΔTλmin between before and after the test was calculated at a wavelength λmin that indicated the minimum transmittance before the test in the wavelength range of 330 nm to 780 nm. The transmittance difference is better when it is closer to zero, with |ΔTλmin|≦15 being preferred and |ΔTλmin|≦10 being even more preferred. In Comparative Example 4, in which the colorant was CB, wavelength-selective absorption was not achieved, and therefore Δλmin was not measured.

[0140] (Heat Resistance) A heat resistance test was conducted on the optical film as a reliability test. The heat resistance test was conducted using an environmental testing machine (SU-221, manufactured by ESPEC Corporation) at 90°C for 500 hours. Before and after the test, transmittance was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.), and the transmittance difference ΔTλmin between before and after the test at a wavelength λmin that indicated the minimum transmittance before the test in the wavelength range of 330 nm to 780 nm was calculated. The transmittance difference is better when it is closer to zero, and |ΔTλmin|≦15 is preferable, and |ΔTλmin|≦10 is even more preferable. Note that in Comparative Example 4, in which the colorant was CB, there was no wavelength selective absorption, so Δλmin was not measured.

[0141] (Ultraviolet Shielding Ratio on Colored Layer) For optical films (Examples 1 to 4, 6 to 12, Comparative Examples 1 to 5) in which a transparent substrate is located above the colored layer in the layer configurations shown in Tables 4 and 5, the transmittance of the transparent substrate was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.). For optical films (Example 5) in which a transparent substrate is located below the colored layer in the layer configurations shown in Tables 4 and 5 and a functional layer is located above the colored layer, the functional layer above the colored layer was peeled off using cellophane tape in accordance with the adhesion test described in JIS K 5600, and the transmittance of the functional layer was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.) using the cellophane tape as a reference. The average transmittance [%] in the ultraviolet range (290 nm to 400 nm) was calculated from the measured transmittance, and the ultraviolet shielding rate [%] was calculated as the value obtained by subtracting the average transmittance [%] in the ultraviolet range (290 nm to 400 nm) from 100%.

[0142] (Haze) The haze of the optical film was measured using a haze meter (NDH7000, manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with the haze test method of JIS K 7136:2000, Testing Methods for Optical Properties of Plastics. Note that, in Examples 4 to 7, the colored layer was the same as in Example 1, so haze measurement was not performed.

[0143] (Coating Film Appearance) The appearance of the colored layer of the optical film was observed using an optical microscope ECLIPSE LV100 (manufactured by Nikon Corporation) at a magnification of 1000 and reference air, and the appearance was evaluated as "Good" when no particles were observed on the entire film surface, "Good" when small particles with a diameter of less than 1 μm were observed, and "Poor" when large particles with a diameter of 1 μm or more were observed. Note that in Examples 4 to 7, the colored layer was the same as in Example 1, so the coating film appearance was not evaluated.

[0144] [Method for Evaluating Display Device Characteristics] (White Display Transmission Characteristics) The transmittance of the optical film was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.), and the transmittance was used to calculate the efficiency of light transmitted through the optical film during white display, which was evaluated as white display transmission characteristics. The efficiency was calculated as the light intensity value (light intensity ratio) at each wavelength of light transmitted through the optical film, when the light intensity at each wavelength during white display emitted from a white organic EL light source and output through a color filter was set to 100. The higher the light intensity ratio, the higher the luminance efficiency of the light source. Figure 8 shows the spectrum during white display when output through a white organic EL light source and a color filter. In addition, to evaluate the effect of the colored layer on luminance efficiency, the ratio of the efficiency of each example to the efficiency of Comparative Example 7, in which the optical film did not have a colored layer, was calculated.

[0145] (Display Device Reflection Characteristics) FIG. 9 shows a schematic diagram for explaining a method for calculating the display device reflection characteristics. Ｄ６５ (λ) is the spectrum of the D65 light source, R Ｅ(λ) represents the electrode reflectance, R1(λ) represents the internal reflection component, R2(λ) represents the surface reflectance, and R(λ) represents the sum of R1(λ) and R2(λ) and represents the reflectance on the observer side. Also, reference numeral 10A denotes an optical film, reference numeral 11 represents a transparent substrate, reference numeral 11a represents the optical film surface, reference numeral 11b represents the optical film back surface, reference numeral 12 represents a colored layer, reference numeral 13 represents a hard coat layer, and reference numeral 14 represents a low refractive index layer. While FIG. 9 shows the layer structure of the optical film of Example 4, the same applies to other layer structures. To evaluate the reflection characteristics of the display device, the transmittance T(λ) and surface reflectance R2(λ) of the optical film were measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.). The surface reflectance R2(λ) was measured by applying a matte black paint to the back surface of the optical film to prevent reflection, and then measuring the spectral reflectance at an incident angle of 5° to obtain the surface reflectance R2(λ). Electrode reflectance R Ｅ The relative reflectance value, where y(λ) is set to 100% for all wavelengths from 380 nm to 780 nm and the light intensity of reflected light reflected from a D65 light source without an optical film in place is set to 100, was calculated based on the following formulas (1) to (4) without considering interface and surface reflections at each layer, and evaluated as the reflection characteristics of the display device. In formulas (1) to (4), y(λ) represents the CIE 1931 color-matching function, Y represents one of the tristimulus values ​​at the white point of the D65 light source, and k represents a constant related to the D65 light source. The lower the relative reflectance value, the lower the intensity of reflected light, and the higher the display quality. Furthermore, to evaluate the effect of the colored layer on the reflection characteristics of the display device, the ratio of the relative reflectance value of each example to the relative reflectance value of Comparative Example 7, in which the optical film did not have a colored layer, was calculated.

[0146]

[0147]

[0148]

[0149]

[0150] (Color reproducibility) The transmittance of the optical film was measured using an automatic spectrophotometer (U-4100, manufactured by Hitachi, Ltd.). Furthermore, the spectra of red, green, and blue colors output through the white organic EL light source and color filter used in the evaluation of white display transmittance were measured. Figure 10 shows the spectra of red, green, and blue colors output through the white organic EL light source and color filter. The BT2020 ratio was calculated from the CIE 1931 chromaticity values ​​calculated using the measured transmittance and the spectra of red, green, and blue colors, and evaluated as color reproducibility. BT2020 refers to the wide color gamut color system defined in the ITU-R (International Telecommunication Union - Radiocommunication Sector) Recommendation BT.2020. The higher the BT2020 ratio, the wider the color reproducibility, which is preferable.

[0151]

[0152]

[0153] The optical films of Examples 1 to 12 had low haze, good coating film appearance, and excellent transparency. They also had good light resistance and heat resistance. Furthermore, displays using these optical films exhibited reduced reflection compared to displays using the optical film of Comparative Example 7, which did not have a colored layer. Furthermore, while circularly polarizing plates are said to reduce transmittance by half, these optical films exhibited excellent luminance efficiency, as indicated by the evaluation value of white display transmittance, and also improved color reproducibility. Comparing Examples 1, 2, 8, 9, 11 to 13 and Comparative Example 1, it can be seen that even colorants with low solubility in solvents can be easily dissolved in the colored layer-forming composition by combining them with a wetting dispersant, and a colored layer with low haze and excellent transparency can be formed, similar to when a highly soluble colorant is used. This effect can also be achieved by changing the type of wetting dispersant and / or active energy ray-curable compound. On the other hand, Comparative Example 2, in which the colored layer-forming composition did not contain a wetting dispersant, and Comparative Examples 3 and 4, in which the colorant was a pigment, exhibited high haze, poor coating film appearance, and inferior transparency. Comparative Examples 3 and 4 were also inferior in white display transmittance characteristics and color reproducibility. Comparative Examples 5 and 6, in which the color layer-forming composition did not contain a radical scavenger, were inferior in light resistance. In particular, Comparative Example 6, which did not have a layer having ultraviolet absorbing ability on the color layer, had poor light resistance.

[0154] Although one embodiment and example of the present invention have been described in detail above, the present invention is not limited to a specific embodiment, and includes modifications and combinations of the configuration within the scope that does not deviate from the gist of the present invention.

[0155] According to the present invention, it is possible to provide a colored layer-forming composition that can form a colored layer that is excellent in transparency and reliability despite containing a colorant that has low solubility in the solvent of the colored layer-forming composition, a method for producing the same, and an optical film having a colored layer that is excellent in transparency and reliability despite containing a colorant that has low solubility in the solvent of the colored layer-forming composition, and a display device using the same.

[0156] 60, 60A, 60B, 60C, 60D, 60E, 60F Optical film 61 Colored layer 62 Transparent substrate 63 Functional layer 63a Low refractive index layer 63b Hard coat layer 63c Antiglare layer

Claims

1. A composition for forming a colored layer, comprising a colorant (A), an active energy ray-curable compound (B), a photopolymerization initiator (C), a radical scavenger (D), a wetting and dispersing agent (E), and a solvent (F), wherein the colorant (A) contains a colorant (A1) having a solubility in the solvent (F) of 0.001% by mass or more but less than 1% by mass at 20°C.

2. The composition for forming a colored layer according to claim 1, wherein the colorant (A1) comprises one or more compounds selected from the group consisting of compounds having either a phthalocyanine structure or a porphyrin structure, and metal complexes thereof.

3. The colored layer forming composition according to claim 1, wherein the half width of the maximum absorption wavelength of the absorption spectrum obtained by dissolving the colorant (A1) in cyclohexanone at a concentration such that the absorbance at the maximum absorption wavelength is 1 is 15 to 30 nm.

4. The colored layer forming composition according to claim 1, wherein the solvent (F) contains either or both of cyclohexanone and acetone.

5. The colored layer forming composition according to claim 4, wherein the solvent (F) contains cyclohexanone and acetone, and the mass ratio of the acetone to the cyclohexanone is 1:

1.

6. A method for producing a colored layer-forming composition, comprising: a step of preparing a colorant dispersion liquid containing a colorant (A1), a wetting dispersant (E), and a solvent (F1); and a step of mixing the colorant dispersion liquid with an active energy ray-curable compound (B), a photopolymerization initiator (C), a radical scavenger (D), and a solvent (F2), wherein the solubility of the colorant (A1) in the mixed solvent of the solvent (F1) and the solvent (F2) is 0.001 mass % or more and less than 1 mass % at 20°C.

7. The method for producing a colored layer-forming composition according to claim 6, wherein the colorant dispersion has a D50 particle size at 50% cumulative volume in a particle size distribution measured by dynamic light scattering of 2000 to 5000 nm.

8. The method for producing a composition for forming a colored layer according to claim 6, wherein the colorant (A1) comprises one or more compounds selected from the group consisting of compounds having either a phthalocyanine structure or a porphyrin structure, and metal complexes thereof.

9. The method for producing a colored layer-forming composition according to claim 6, wherein the half-value width of the maximum absorption wavelength of the absorption spectrum obtained by dissolving the colorant (A1) in cyclohexanone at a concentration such that the absorbance at the maximum absorption wavelength is 1 is 15 to 30 nm.

10. The method for producing a colored layer-forming composition according to claim 6, wherein the solvent (F1) and the solvent (F2) each independently contain either or both of cyclohexanone and acetone.

11. The method for producing a colored layer-forming composition according to claim 10, wherein the solvent (F1) and the solvent (F2) each independently contain cyclohexanone and acetone, and the mass ratio of the acetone to the cyclohexanone is 1:

1.

12. An optical film comprising a sheet-like transparent substrate and a colored layer formed on a first surface of the transparent substrate, wherein the colored layer is a cured product of the colored layer-forming composition described in any one of claims 1 to 5.

13. The optical film according to claim 12, which has a haze value of 1% or less as measured in accordance with the method described in JIS K 7136:2000.

14. The optical film according to claim 12, further comprising a functional layer formed on a second surface of the transparent substrate opposite to the first surface or on the colored layer, wherein one or both of the transparent substrate and the functional layer have an ultraviolet ray blocking rate of 85% or more as measured in accordance with the method specified in JIS L 1925:2019.

15. The optical film according to claim 14, wherein the functional layer has at least one of an anti-reflection function and an anti-glare function.

16. The optical film according to claim 14, wherein the functional layer has at least one of an antistatic function and an antifouling function.

17. A display device comprising the optical film according to claim 12.

Images