Optical film, panel unit, and display device

Abstract

This invention provides a method for achieving both image quality reduction from seams between panel units and sufficient brightness in a display device having a display surface composed of multiple panel units. The invention relates to a film comprising a light-transmitting layer containing particles and a colorant and having a total light transmittance of 10% to 30%, for use in a display device having a display surface composed of multiple panel units.

Description

Technical Field

[0001] The present invention relates to an optical film for a display device having a display surface composed of a plurality of panel units, a panel unit for the display device, and the display device. Background Technology

[0002] As a next-generation display device to replace various liquid crystal display devices, self-emissive display devices have been developed, represented by the Micro LED display device described in Japanese Patent Application Publication No. 2018-14481 (corresponding to U.S. Patent Application Publication No. 2018 / 0019233, U.S. Patent Application Publication No. 2018 / 0331085, or U.S. Patent No. 2018 / 0331086).

[0003] In such a self-emissive display, in order to avoid the negative impact of light reflected from the substrate, which houses the light-emitting element as a light source, on the image quality of the display, a light-shielding layer that absorbs visible light was stacked on the display surface side of the light-emitting module containing the light-emitting element.

[0004] Japanese Patent Application Publication No. 2019-204905 discloses a self-emissive display comprising a light-emitting module consisting of multiple light-emitting elements mounted on a wiring substrate, a black sealing material sheet using an olefin-based resin as the matrix resin and having a visible light transmittance of 5% to 70%, and a transparent optical layer (transparent layer). In this self-emissive display, the black sealing material sheet is laminated onto the light-emitting module, covering the surfaces of the light-emitting elements and the wiring substrate, and the transparent optical layer is laminated onto the black sealing material sheet. Furthermore, this document discloses that the black sealing material sheet exhibits excellent properties as a light-shielding layer, and that the layer structure of the self-emissive display can be simplified compared to existing self-emissive displays, resulting in improved productivity of the self-emissive display. Summary of the Invention

[0005] According to Japanese Patent Application Publication No. 2019-204905, a black sealing material sheet can suppress image quality degradation originating from seams between panel units when used in a display device having a display surface composed of multiple panel units. However, in display devices using the black sealing material sheet of Japanese Patent Application Publication No. 2019-204905, there is a problem of a significant reduction in brightness.

[0006] Therefore, the object of the present invention is to provide a means for suppressing the reduction in image quality caused by the seams between the panel units in a display device having a display surface composed of multiple panel units, while achieving sufficient brightness.

[0007] The aforementioned problems of the present invention can be solved by the following means.

[0008] An optical film comprising particles and a colorant, having a total light transmittance of 10% to 30%.

[0009] A display device for having a display surface composed of multiple panel units. Attached Figure Description

[0010] Figure 1 (A) to (C) represent schematic diagrams of the cross-sectional structure of the optical film used in one embodiment of the present invention. 1 represents the light-transmitting layer A described later, 2 represents the laminated film, 3 represents the light-transmitting layer B described later, 3' represents the layer or film that serves as the base (foundation) of the light-transmitting layer B, and 4 represents the hard coating layer.

[0011] Figure 2 This is a schematic diagram illustrating an example of an optical film manufacturing apparatus according to one embodiment of the present invention. 100 represents a laminate (laminated film), 110 represents a support (e.g., a substrate layer such as light-transmitting layer B), 200 represents a manufacturing apparatus, 201 represents a roller of the support (e.g., a substrate layer such as light-transmitting layer B), 210 represents a supply section, 220 represents a coating section, 221 represents a support roller, 222 represents a coating head, 223 represents a pressure reduction chamber, 230 represents a drying section, 231 represents a drying chamber, 232 represents an inlet for drying gas, 233 represents an outlet, 240 represents a cooling section, 241 represents a cooling chamber, 242 represents a cooling air inlet, 243 represents a cooling air outlet, 250 represents a winding section, 251 represents a roller of the laminate (laminated film), and a, b, c, and d represent conveyor rollers.

[0012] Figure 3 This is a schematic diagram showing the cross-sectional structure of a panel unit according to one embodiment of the present invention. 1 represents the light-transmitting layer A described later, 2 represents the laminated film, 3 represents the light-transmitting layer B described later, 3' represents a layer or film that serves as the base (foundation) of the light-transmitting layer B, 4 represents the hard coating layer, 10 represents the panel unit, 11 represents the LED module, and 12 represents the adhesive layer.

[0013] Figure 4 This is a schematic diagram showing the planar structure of a modular display device according to one embodiment of the present invention. 10 represents a panel unit, and 20 represents a modular display device. Detailed Implementation

[0014] In this instruction manual, the range "X~Y" means "above X and below Y". Furthermore, unless otherwise specified, operation and physical properties are measured at room temperature (20~25℃) and relative humidity 40~50%RH.

[0015] In addition, in this specification, (co)polymer refers to the collective term including copolymers and homopolymers.

[0016] Furthermore, in this specification, "(meth)acrylate" refers to the collective term for acrylates and methacrylates. Similarly, compounds containing "(methyl)" such as (meth)acrylic acid are also a collective term for compounds whose names contain "methyl" and compounds that do not contain "methyl".

[0017] The following, as needed, will be referenced in the appendix. Figure 1 The embodiments of the present invention will be described below. It should be noted that in the description of the drawings, the same symbols are used to denote the same elements, and repeated descriptions are omitted. Furthermore, the dimensions in the drawings are exaggerated for ease of explanation and may differ from the actual dimensions.

[0018] <Transparent Layer A>

[0019] One aspect of the present invention relates to an optical film comprising a light-transmitting layer containing particles and a colorant and having a total light transmittance of 10% to 30%, the optical film being used in a display device having a display surface composed of multiple panel units. According to one aspect of the present invention, a mechanism can be provided in a display device having a display surface composed of multiple panel units that can simultaneously achieve a reduction in image quality caused by seams between the panel units and sufficient brightness.

[0020] It should be noted that in this specification, the layer containing particles and colorants and having a total light transmittance of 10% to 30% is also referred to as translucent layer A.

[0021] The inventors hypothesize the following mechanism by which the problem can be solved according to the present invention.

[0022] In a display device having a display surface composed of multiple panel units, when external light is incident on the device, it is reflected by a substrate or other structure housing light-emitting elements that serve as light sources, producing reflected light. Furthermore, at the seams between the panel units, for example, the reflected light is reflected or refracted by the sides of adjacent panel units and exits onto the display surface, resulting in localized light scattering. This localized light scattering leads to a decrease in image quality originating from the seams between the panel units.

[0023] The black sealing material sheet disclosed in Japanese Patent Application Publication No. 2019-204905 absorbs visible light, thus reducing reflected light towards the display surface by absorbing reflected light from a substrate on which a light-emitting element is mounted as a light source. Furthermore, it also reduces emitted scattered light. This suppresses image quality degradation originating from seams between panel units. However, because the black sealing material sheet in Japanese Patent Application Publication No. 2019-204905 absorbs most of the emitted light from the light-emitting element, the brightness is significantly reduced in panel units or display devices equipped with such a sheet.

[0024] On the other hand, in this invention, the light-transmitting layer A contains a colorant, and the total light transmittance is 10% to 30%. The light-transmitting layer A has the function of absorbing visible light within an appropriate range, thus reducing reflected light towards the display surface by absorbing reflected light from a substrate, such as one on which a light-emitting element is mounted as a light source. Furthermore, the amount of scattered light emitted is also reduced. Additionally, the absorption of emitted light from the light-emitting element as a light source is also below a certain value. Therefore, sufficient brightness can be obtained in a panel unit or display device equipped with the optical film of this invention. Furthermore, in this invention, the light-transmitting layer A contains particles. Since the particles scatter all reflected light from a substrate, such as one on which a light-emitting element is mounted as a light source, even when light scattering occurs at the seams between panel units, the scattering becomes less noticeable compared to the case where light scattering only occurs locally in that area. Furthermore, emitted light from the light-emitting element as a light source is also scattered to a certain extent, so even when light scattering occurs at the seams between panel units, the scattering becomes less noticeable.

[0025] It should be noted that the above mechanism is purely speculative, and its correctness or incorrectness has no impact on the technical scope of this invention.

[0026] (Matrix material)

[0027] In one embodiment of the present invention, the light-transmitting layer A preferably comprises a matrix material. The matrix material imparts self-supporting properties to the film and plays a role in retaining particles within the film.

[0028] There is no particular limitation on the content of the matrix material. From the viewpoint of light transmittance, it is preferable to exceed 50% by mass, more preferably exceed 80% by mass, and even more preferably exceed 90% by mass relative to the total mass of the light-transmitting layer A. In addition, from the viewpoint of light absorption and light scattering, the content of the matrix material is preferably less than 100% by mass relative to the total mass of the light-transmitting layer A.

[0029] There are no particular restrictions on the matrix material; it can be either inorganic or organic, with organic materials being preferred.

[0030] Furthermore, the light-transmitting layer A is preferably a light-transmitting resin layer such as a resin film. A light-transmitting resin layer refers to a light-transmitting layer containing resin as a matrix material, and a resin film refers to a film containing resin as a matrix material. There are no particular limitations on the resin used as the matrix material; examples include acrylic resins (e.g., methyl methacrylate-methyl acrylate copolymer resin), polycarbonate resins, polyolefin resins (e.g., polyethylene resin, polypropylene resin), cyclic olefin resins (COP), polyimide resins, cellulose resins (e.g., cellulose triacetate, cellulose diacetate, cellulose acetate propionate), and polyester resins (e.g., polyethylene terephthalate (PET), polyethylene terephthalate (PTT), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), etc.). Among these, cyclic olefin resins are preferred from the viewpoint of haze value and optical uniformity, and cyclic olefin resins having polar groups are more preferred from the viewpoint of the dispersibility of inorganic particles and colorants (especially pigments). Examples of polar groups include carboxyl, hydroxyl, alkoxycarbonyl, allyloxycarbonyl, amino, amide, cyano, groups formed by bonding these groups with linking groups such as methylene, carbonyl, ether, silyl ether, thioether, imine, and other polar divalent organic groups bonded as linking groups. Among these groups, cycloolefin resins containing a carboxyl group are preferred. It should be noted that when the polar group is a group capable of forming a salt, the polar group can form a salt.

[0031] There are no particular limitations on the cyclic olefin resin, but a (co)polymer of a cyclic olefin monomer represented by the following general formula (A) is preferred.

[0032]

[0033] In general formula (A), each R independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted hydrocarbon group with 1 to 30 carbon atoms, or a polar group. In addition, a and b in general formula (A) independently represent integers greater than 0.

[0034] Furthermore, as a cyclic olefin resin, a (co)polymer of a cyclic olefin monomer represented by the following general formula (A-1) or the following general formula (A-2) is more preferred.

[0035] First, the cyclic olefin monomers represented by the general formula (A-1) will be explained.

[0036] General formula (A-1)

[0037]

[0038] R in general formula (A-1) 1 ~R 4Each of these groups independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted hydrocarbon group with 1 to 30 carbon atoms, or a polar group. Except for R... 1 ~R 4 In the case where all atoms are hydrogen, R does not exist. 1 With R 2 Simultaneously a hydrogen atom or R 3 With R 4 The case where it is both a hydrogen atom.

[0039] The halogen atom is not particularly limited, but fluorine, chlorine, bromine, and iodine atoms are preferred. The hydrocarbon group with 1 to 30 carbon atoms is not particularly limited, but alkyl groups with 1 to 30 carbon atoms are preferred. The polar group is not particularly limited, but groups such as carboxyl, hydroxyl, alkoxycarbonyl, allyloxycarbonyl, amino, amide, cyano, carbonyl, ether, silyl ether, thioether, and imine, which are polar divalent organic groups bonded together as linking groups, are preferred. Among these groups, carboxyl, hydroxyl, alkoxycarbonyl, or allyloxycarbonyl are more preferred. Furthermore, from the viewpoint of ensuring solubility during solution film formation, alkoxycarbonyl or allyloxycarbonyl is even more preferred.

[0040] From the perspective of ensuring the solubility of cyclic olefin resins during solution film formation, R 1 ~R 4 At least one of them is preferably a polar group.

[0041] In the general formula (A-1), p represents an integer from 0 to 2. From the viewpoint of improving the heat resistance of the film, p is preferably 1 to 2. When p is 1 to 2, the volume of the resulting resin increases, and the glass transition temperature is more easily increased.

[0042] Next, we will explain the cyclic olefin monomers represented by the general formula (A-2).

[0043] General formula (A-2)

[0044]

[0045] R in general formula (A-2) 5 This refers to an alkylsilyl group having a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, or an alkyl group having 1 to 5 carbon atoms. Wherein, R... 5 Preferably, it is a hydrocarbon group with 1 to 3 carbon atoms.

[0046] R in general formula (A-2) 6This indicates a polar group or a halogen atom. There are no particular limitations on the polar group, but carboxyl, hydroxyl, alkoxycarbonyl, allyloxycarbonyl, amino, amide, or cyano groups are preferred. There are no particular limitations on the halogen atom, but fluorine, chlorine, bromine, or iodine atoms are preferred. Among these groups, R... 6 The preferred group is a polar group, more preferably a carboxyl group, a hydroxyl group, an alkoxycarbonyl group, or an allyloxycarbonyl group. Furthermore, from the viewpoint of ensuring solubility during solution film formation, an alkoxycarbonyl group or an allyloxycarbonyl group is even more preferred.

[0047] Using cyclic olefin monomers represented by the general formula (A-2) reduces the symmetry of the molecules, making it easier to promote the diffusion of the resin during solvent evaporation.

[0048] In the general formula (A-2), p represents an integer from 0 to 2.

[0049] The following are specific examples of the structures of general formulas (A-1) and (A-2).

[0050]

[0051] Examples of copolymerizable monomers capable of copolymerizing with cyclic olefin monomers represented by general formula (A-1) or general formula (A-2) include copolymerizable monomers capable of ring-opening copolymerization with cyclic olefin monomers represented by general formula (A-1) or general formula (A-2), and copolymerizable monomers capable of addition copolymerization with cyclic olefin monomers represented by general formula (A-1) or general formula (A-2).

[0052] Examples of comonomers capable of ring-opening copolymerization with cyclic olefin monomers represented by general formula (A-1) or general formula (A-2) include other cyclic olefin monomers such as cyclobutene, cyclopentene, cycloheptene, cyclooctene, and dicyclopentadiene.

[0053] Examples of comonomers capable of addition copolymerization with cyclic olefin monomers represented by general formula (A-1) or general formula (A-2) include compounds containing unsaturated double bonds, vinyl cyclic hydrocarbon compounds, and (meth)acrylates. Examples of compounds containing unsaturated double bonds include olefin compounds with 2 to 12 carbon atoms (preferably 2 to 8), including ethylene, propylene, and butene. Examples of vinyl cyclic hydrocarbon compounds include vinylcyclopentene monomers such as 4-vinylcyclopentene and 2-methyl-4-isopropenylcyclopentene. Examples of (meth)acrylates include alkyl (meth)acrylates with 1 to 20 carbon atoms, such as methyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and cyclohexyl (meth)acrylate.

[0054] The content of structural units derived from cyclic olefin monomers represented by general formula (A-1) or general formula (A-2) relative to the total number of structural units constituting the cyclic olefin resin is preferably 50 to 100 mol%, more preferably 60 to 100 mol%, and even more preferably 70 to 100 mol%.

[0055] As a cyclic olefin resin, a polymer obtained by homopolymerization or copolymerization of cyclic olefin monomers represented by general formula (A-1) or general formula (A-2) is preferred, for example, the following polymers. Among these polymers, (1) to (3) and (5) are preferred, and (3) and (5) are more preferred.

[0056] (1) Ring-opening polymers of cyclic olefin monomers represented by general formula (A-1) or general formula (A-2);

[0057] (2) Ring-opening copolymers of cyclic olefin monomers and copolymeric monomers represented by general formula (A-1) or general formula (A-2);

[0058] (3) The enhanced (co)polymer of the ring-opening (co)polymer of (1) or (2) above;

[0059] (4) The (co)polymer obtained by hydrogenation after cyclizing the ring-opening (co)polymer of (1) or (2) above through the Fred-Cleifur reaction;

[0060] (5) A copolymer of a cyclic olefin monomer represented by general formula (A-1) or general formula (A-2) and a compound containing an unsaturated double bond;

[0061] (6) Addition (co)polymers of cyclic olefin monomers represented by general formula (A-1) or general formula (A-2) and their hydrogenated (co)polymers;

[0062] (7) Alternating copolymers of cyclic olefin monomers represented by general formula (A-1) or general formula (A-2) with methacrylates or acrylates.

[0063] Furthermore, examples of cyclic olefin resins include those having at least one of the structural units represented by the following general formula (B-1) and the following general formula (B-2). From the viewpoint that the resulting cyclic olefin resin has a high glass transition temperature and readily produces a film with high permeability, polymers comprising the structural unit represented by general formula (B-2) or copolymers of the structural units represented by general formula (B-1) and the structural units represented by general formula (B-2) are preferred.

[0064] General formula (B-1)

[0065]

[0066] In general formula (B-1), X is a group represented by -CH=CH- or a group represented by -CH2CH2. R 1 ~R 4 And p are respectively related to R in general formula (A-1) 1 ~R 4 Same as p.

[0067] General formula (B-2)

[0068]

[0069] In general formula (B-2), X is a group represented by -CH=CH- or -CH2CH2-. R in general formula (B-2) 5 R 6 And p are respectively related to R in general formula (A-2) 5 R 6 Same as p.

[0070] Intrinsic viscosity [η] of cyclic olefin resins inh There are no particular restrictions, but 0.2 to 5 cm is preferred. 3 / g, more preferably 0.3-3cm 3 / g, more preferably 0.4–1.5cm 3 / g. Intrinsic viscosity of cyclic olefin resins [η] inh It can be determined by JIS K 7367-1:2002.

[0071] The number-average molecular weight (Mn) of the cyclic olefin resin is not particularly limited, but is preferably 8,000 to 100,000, more preferably 10,000 to 80,000, and even more preferably 12,000 to 50,000. Furthermore, the weight-average molecular weight (Mw) of the cyclic olefin resin is not particularly limited, but is preferably 20,000 to 300,000, more preferably 30,000 to 250,000, and even more preferably 40,000 to 200,000. The number-average molecular weight (Mn) and weight-average molecular weight (Mw) can be determined by gel permeation chromatography (GPC) according to polystyrene conversion.

[0072] If the intrinsic viscosity [η] inh If the number-average molecular weight and weight-average molecular weight are within the above ranges, then the cyclic olefin resin has better heat resistance, water resistance, chemical resistance, mechanical properties, and molding and processability as a film.

[0073] The glass transition temperature (Tg) of cycloolefin resins is not particularly limited, but is preferably 110°C or higher, more preferably 110–350°C, even more preferably 120–250°C, and particularly preferably 120–220°C. If the Tg is 110°C or higher, deformation is less likely to occur during secondary processing such as use, coating, and printing under high-temperature conditions. On the other hand, if the Tg is below 350°C, molding and processing are easier, and the possibility of resin degradation due to heat during molding and processing is lower. The Tg of cycloolefin resins can be determined according to JIS K 7121-1987.

[0074] Cycloolefin resins can be commercially available or synthetic. Examples of commercially available resins are not particularly limited, such as ARTON G (e.g., ARTON G7810), ARTON F, ARTON R, and ARTON RX manufactured by JSR Corporation.

[0075] Cycloolefin resins can be used alone, or two or more can be used simultaneously.

[0076] In addition, a single matrix material can be used, or two or more materials can be used simultaneously.

[0077] (particle)

[0078] In one embodiment of the present invention, the light-transmitting layer A contains particles. These particles, dispersed within the light-transmitting layer A, scatter light transmitted through the optical film. Therefore, when the light-transmitting layer A does not contain particles, the reduction in image quality originating from the seams between the panel units in a display device having a display surface composed of multiple panel units is not adequately suppressed.

[0079] It should be noted that the particles described in this specification do not contain the colorants described later.

[0080] As particles, there are no particular restrictions; examples include organic particles, inorganic particles, and organic-inorganic composite particles.

[0081] As organic particles, there are no particular limitations; examples include polymethyl methacrylate beads, acrylic-styrene copolymer beads, melamine beads, polycarbonate beads, styrene beads, cross-linked polystyrene beads, polyvinyl chloride beads, and benzoguanamine-melamine-formaldehyde beads.

[0082] As inorganic particles, there are no particular limitations. Examples include inorganic oxide particles composed of at least one oxide selected from zirconium, titanium, aluminum, indium, zinc, tin, antimony, cerium, niobium, tungsten, silicon, etc. Specifically, examples include ZrO2, ZrSiO4, TiO2, BaTiO3, SrTiO3, Al2O3, zeolite, In2O3, ITO (Indium Tin Oxide), ZnO, SnO2, Sb2O3, CeO2, Nb2O5, WO3, and silicon dioxide (SiO2).

[0083] Among these particles, inorganic particles are preferred, inorganic oxide particles are more preferred, silicon-containing oxides are even more preferred, and silicon dioxide (SiO2) is particularly preferred.

[0084] In addition, particles can have multi-layered structures, such as the core-shell structure.

[0085] These particles can be used with or without surface treatment.

[0086] In the case of surface treatment, specific materials for surface treatment include various types of inorganic oxides such as silicon dioxide and zirconium oxide, metal hydroxides such as aluminum hydroxide, organosiloxanes, and organic acids such as stearic acid. These surface treatment materials can be used alone or in combination. From the viewpoint of the stability of the dispersion, at least one of various types of inorganic oxides and metal hydroxides is preferred as the surface treatment material, and metal hydroxides are more preferred.

[0087] The average secondary particle size is not particularly limited, but is preferably 50 nm or more, more preferably 100 nm or more, and even more preferably 150 nm or more. Within this range, the effect of suppressing image quality degradation originating from seams between panel units is further improved. Furthermore, the average secondary particle size is preferably 1000 nm or less, more preferably 500 nm or less, and even more preferably 300 nm or less. Within this range, the effect of suppressing image quality degradation as a whole, resulting in less sharp images, is further improved.

[0088] The average secondary particle size can be obtained by directly measuring the size of the secondary particles from electron microscope images of the layer. Specifically, particle images are measured using a transmission electron microscope (TEM) (Hitachi Hi-Tech H-7650, Ltd.), and the average value of the equivalent diameter of 100 randomly selected secondary particles is calculated as the average secondary particle size.

[0089] The particles can be either commercially available or synthetic. As for commercially available particles, there are no particular restrictions; for example, the R972V manufactured by AEROSIL Co., Ltd. of Japan can be cited.

[0090] One type of particle can be used alone, or two or more types can be used simultaneously.

[0091] The particle content in the light-transmitting layer A is not particularly limited, but is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, further preferably 0.1 parts by mass or more, and particularly preferably 0.3 parts by mass or more, relative to 100 parts by mass of the substrate material. Within this range, the effect of suppressing image quality degradation originating from seams between panel units is further improved. Furthermore, the particle content in the light-transmitting layer A is not particularly limited, but is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and further preferably 1 part by mass or less, relative to 100 parts by mass of the substrate material. Within this range, the effect of suppressing image quality degradation as a whole, resulting in a less vivid image, is further improved.

[0092] (Coloring agent)

[0093] In one embodiment of the present invention, the light-transmitting layer A comprises a colorant. The colorant functions to color the light-transmitting layer A and thus control the total light transmittance of the optical film. Therefore, when the light-transmitting layer A does not contain a colorant, the suppression of image quality degradation originating from the seams between the panel units in a display device having a display surface composed of multiple panel units becomes insufficient.

[0094] There are no particular limitations on colorants; examples include dyes and pigments.

[0095] As pigments, there are no particular limitations; for example, organic and inorganic pigments, minerals, etc., listed in the color index can be cited.

[0096] As a black pigment, there are no particular limitations; examples include carbon black, magnetic materials, and iron-titanium composite oxide black. Specifically, as carbon black, there are no particular limitations; examples include channel black, furnace black, acetylene black, thermal cracking black, and lampblack. Similarly, as a magnetic material, there are no particular limitations; examples include ferrite and magnetite.

[0097] As a red or magenta pigment, there are no particular limitations. Examples include CIPigment Red 3, 5, 19, 22, 31, 38, 43, 48:1, 48:2, 48:3, 48:4, 48:5, 49:1, 53:1, 57:1, 57:2, 58:4, 63:1, 81, 81:1, 81:2, 81:3, 81:4, 88, 104, 108, 112, 122, 123, 144, 146, 149, 166, 168, 169, 170, 177, 178, 179, 184, 185, 208, 216, 226, 257; Pigment Violet 3, 19, 23, 29, 30, 37, 50, 88; and Pigment Orange. 13, 16, 20, 36, Ruby (chromium corundum), Garnet, Spinel, etc.

[0098] There are no particular restrictions on the use of cyan or blue-green pigments. Examples include CIPigment Blue 1, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17-1, 22, 27, 28, 29, 36, 60, and blue sapphire (corundum containing iron and titanium).

[0099] As a green pigment, there are no particular restrictions; examples include CIPigment Green 7, 26, 36, and 50.

[0100] There are no particular restrictions on yellow pigments. Examples include CIPigment Yellow 1, 3, 12, 13, 14, 17, 34, 35, 37, 55, 74, 81, 83, 93, 94, 95, 97, 108, 109, 110, 137, 138, 139, 153, 154, 155, 157, 166, 167, 168, 180, 185, 193, and yellow sapphire (containing nickel corundum).

[0101] In addition, there are no particular restrictions on the dyes used, and examples of dyes that are already known can be cited, such as those described in paragraphs “0057” to “0060” of International Publication No. 2015 / 111351.

[0102] As a colorant, when the matrix material is resin, pigments are preferred from the viewpoint of having good dispersion stability relative to resin and excellent weather resistance. That is, in one embodiment of the present invention, the light-transmitting layer A more preferably further comprises pigments and resin in addition to the particles described above. Furthermore, among the pigments, black pigments are more preferred from the viewpoint of further suppressing color changes in the image and better exerting the effects of the present invention, and carbon black is even more preferred.

[0103] When the colorant is a pigment, the average secondary particle size of the pigment is not particularly limited, but is preferably 0.1 μm or more, more preferably 0.2 μm or more. Within this range, the sliding properties are better, and it is less prone to agglomeration, thereby further reducing the non-uniformity of the film's total light transmittance. Furthermore, the average secondary particle size of the pigment is not particularly limited, but is preferably less than 3 μm, more preferably less than 2.6 μm. Within this range, it is less likely to form dispersed spots in the film, further reducing the non-uniformity of the film's total light transmittance and lowering the haze value.

[0104] The average secondary particle size of the pigment can be determined by directly measuring the size of the secondary particles from electron microscope images of the layer. Specifically, the particle images are measured using a transmission electron microscope (TEM) (Hitachi Hi-Tech H-7650, Ltd.), and the average value of the equivalent diameter of the equal area circle of 100 randomly selected secondary particles is calculated as the average secondary particle size.

[0105] Colorants can be commercially available or synthetic. As for commercially available products, there are no particular restrictions; for example, Mitsubishi Chemical Corporation's #950 can be cited.

[0106] A single colorant can be used alone, or two or more can be used simultaneously.

[0107] The content of the colorant in the light-transmitting layer A is not particularly limited, but relative to 100 parts by weight of the substrate material, it is preferably 0.01 parts by weight or more, more preferably 0.05 parts by weight or more, and even more preferably 0.1 parts by weight or more. Within this range, the suppression effect of image quality degradation originating from the seams between the panel units is further improved. Furthermore, the content of the colorant in the light-transmitting layer A is not particularly limited, but relative to 100 parts by weight of the substrate material, it is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, even more preferably 1 part by weight or less, and particularly preferably 0.6 parts by weight or less. Within this range, the brightness is further improved.

[0108] (Other ingredients)

[0109] In one embodiment of the present invention, the light-transmitting layer A may further contain other components besides those described above, provided that the effects of the present invention are not impaired. There are no particular limitations on these other components; for example, components used in the fields of optical films and functional layers for optical applications can be cited. Specifically, examples include phase difference modifiers, wavelength dispersion modifiers, plasticizers, ultraviolet absorbers, antioxidants, hydrogen-hydrogen bond solvents, and ionic surfactants, but the invention is not limited to these solvents.

[0110] (Total light transmittance)

[0111] In one embodiment of the present invention, the total light transmittance of the light-transmitting layer A is 10% to 30%. If the total light transmittance is less than 10%, the brightness becomes insufficient in a display device having a display surface composed of multiple panel units. Furthermore, if the total light transmittance exceeds 30%, the suppression of image quality degradation originating from the seams between the panel units in a display device having a display surface composed of multiple panel units becomes insufficient. From the viewpoint of simultaneously improving the suppression of image quality degradation originating from the seams between the panel units and brightness, the total light transmittance of the light-transmitting layer A is preferably 15% to 25%.

[0112] Total light transmittance was measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K7361-1:1997 (Test method for total light transmittance of transparent plastic materials).

[0113] (Surface modification treatment of translucent layer A)

[0114] The translucent layer A can undergo surface modification treatment. There are no particular limitations on the methods of surface modification treatment, such as corona discharge treatment, flame treatment, oxidation treatment, plasma treatment, etc.

[0115] (film thickness)

[0116] The thickness of the light-transmitting layer A is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, further preferably 5 μm or more, and particularly preferably 8 μm or more. Within this range, the suppression effect of image quality degradation originating from the seams between the panel units in a display device having a display surface composed of multiple panel units is further improved. Furthermore, the thickness of the light-transmitting layer A is preferably less than 50 μm, more preferably less than 20 μm, further preferably 15 μm or less, and particularly preferably 10 μm or less. Within this range, the brightness is further improved in a display device having a display surface composed of multiple panel units.

[0117] <Optical film comprising light-transmitting layer A and substrate layer>

[0118] In one embodiment of the present invention, the light-transmitting layer A described above can be used as a single-layer film consisting only of this layer, or it can be part of an optical film, but preferably it is part of an optical film.

[0119] In one embodiment of the present invention, the optical film preferably further comprises a substrate layer as another layer. The substrate layer can help protect the light-transmitting layer A, impart mechanical properties to the optical film, and improve the processability of the optical film. Additionally, the substrate layer can be a release film that is peeled off during use. It should be noted that, as described below, the substrate layer can have functional layers on one or both sides.

[0120] There are no particular limitations on the substrate layer, but the light-transmitting layer B is preferred. The light-transmitting layer B is not particularly limited as long as it allows at least a portion of the incident light to pass through. The total light transmittance of the light-transmitting layer B is preferably 50% or more, more preferably 60% or more, further preferably 80% or more, and particularly preferably 90% or more. If it is within such a range, when using an optical film comprising the aforementioned light-transmitting layer A and the light-transmitting layer B as another light-transmitting layer, the brightness is further improved in a display device having a display surface composed of multiple panel units. Furthermore, the total light transmittance of the light-transmitting layer B is not particularly limited, but is more preferably 95% or less, further preferably 93% or less, and particularly preferably 91% or less. If it is within this range, it is easier to satisfy the relationship between the haze values ​​of the light-transmitting layer A and the light-transmitting layer B, as described later.

[0121] Total light transmittance was measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K7361-1:1997 (Plastics—Test method for total light transmittance of transparent materials).

[0122] In one embodiment of the present invention, the preferred substrate layer of the optical film is a light-transmitting layer B, which serves as another light-transmitting layer. The light-transmitting layer B is disposed on the light-transmitting layer A. When measuring the haze of a stack of light-transmitting layers A and B, the values ​​Hz(A-B) (%) when light is incident from the light-transmitting layer A side and the values ​​Hz(B-A) (%) when light is incident from the light-transmitting layer B side satisfy the relationship that Hz(A-B) < Hz(B-A). By satisfying this relationship, the reduction in image quality originating from the seams between the panel units in a display device having a display surface composed of multiple panel units is further improved. The reason for this is presumably that by distributing the optical film with the light-transmitting layer A facing the light-emitting module side and the light-transmitting layer B facing the display surface side (i.e., the visual recognition side of the display device), the light transmitted through the optical film is further scattered. However, whether this is correct or not does not affect the scope of the present invention.

[0123] The haze value can be measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K 7136:2000.

[0124] It should be noted that in this specification, "a light-transmitting layer B is disposed on the light-transmitting layer A" means not only that the light-transmitting layer B is disposed on the surface of the light-transmitting layer A in contact with the light-transmitting layer A, but also that the light-transmitting layer B is disposed on the light-transmitting layer A through other components. Among these configurations, the configuration in which the light-transmitting layer B is disposed on the surface of the light-transmitting layer A in contact with the light-transmitting layer A is preferred.

[0125] In addition, in one embodiment of the present invention, there may be one or more substrate layers, preferably one. It should be noted that whether the optical film has only one substrate layer or has two or more substrate layers, it is preferable that the light-transmitting layer A constitutes one of the outermost surfaces of the optical film.

[0126] (Matrix material of the substrate layer)

[0127] The substrate layer (in the case of a functional layer described later, a layer or film that serves as the matrix (i.e., the base) of the substrate layer) preferably contains a matrix material. It should be noted that in this specification, when a substrate layer represented by a light-transmitting layer B, described later, has a functional layer described later, the layer or film on which the functional layer is formed is referred to as the "matrix" or "base".

[0128] There is no particular limitation on the content of the matrix material. From the viewpoint of light transmittance, the total mass of the substrate layer (when the substrate layer has a functional layer described later, the layer or film that serves as the base of the substrate layer, etc.) is preferably more than 50% by mass, more preferably more than 80% by mass, and even more preferably more than 90% by mass. In addition, from the viewpoint of light absorption and light scattering, the content of the matrix material is preferably less than 100% by mass relative to the total mass of the substrate layer (when the substrate layer has a functional layer described later, the layer or film that serves as the base of the substrate layer, etc.).

[0129] The base material for the substrate layer (a layer or film that serves as the matrix (i.e., the base) in the case where the substrate layer has the functional layers described later) is not particularly limited, and the same materials listed as those used as the base material for the light-transmitting layer A above can be used. Among these layers, organic materials are preferred.

[0130] Furthermore, the substrate layer (in the case where the substrate layer has the functional layers described later, the layer or film that serves as the matrix (i.e., the base) of the substrate layer) is preferably a resin layer such as a resin film (e.g., a light-transmitting resin layer). A resin film refers to a film containing a resin as a matrix material. Examples of resins that serve as the matrix material are the same as those used as the matrix material of the aforementioned light-transmitting layer A. From the viewpoint of haze value, polyester resin is preferred, and polyethylene terephthalate is more preferred.

[0131] The matrix material can be used alone, or two or more can be used at the same time.

[0132] (Other components of the substrate layer)

[0133] The substrate layer (in the case of a functional layer described later, the layer or film that forms the base of the substrate layer) may further contain other components besides the matrix material described above, provided that the effects of the present invention are not impaired. There are no particular limitations on these other components; examples include the particles and colorants described in the light-transmitting layer A above. Furthermore, examples include components used in the fields of optical films and functional layers for optical applications. Specifically, examples include particles, colorants, phase difference modifiers, wavelength dispersion modifiers, plasticizers, ultraviolet absorbers, antioxidants, hydrogen-bonding solvents, ionic surfactants, etc., but are not limited thereto.

[0134] (Surface modification treatment of the substrate layer)

[0135] The substrate layer can undergo surface modification treatment. There are no particular limitations on the methods of surface modification treatment, such as corona discharge treatment, flame treatment, oxidation treatment, plasma treatment, etc.

[0136] (Functional layer of substrate layer)

[0137] The substrate layer may have functional layers on one or both sides of the layer or film that serves as the base. More specifically, the substrate layer may have functional layers on the side of the light-transmitting layer A (i.e., between the light-transmitting layer A and the layer or film that serves as the base) or on the side opposite to the light-transmitting layer A.

[0138] It should be noted that in this specification, when the substrate layer has a functional layer, the entire layer, including the functional layer, is considered the substrate layer. Therefore, for example, when the light-transmitting layer B has a functional layer, the entire layer, including the functional layer, is considered the light-transmitting layer B.

[0139] There are no particular limitations on the functional layer used as the substrate layer; for example, functional layers used in optical applications can be cited. Specifically, examples include release layers, easy-to-adhere layers, antistatic layers, hard coatings, anti-reflective layers, anti-glare layers, partition layers, buffer layers, and slip-resistant layers, but these are not limited to. Among these layers, easy-to-adhere layers or hard coatings are preferred, and easy-to-adhere layers are more preferred.

[0140] There are no particular restrictions on what is used as an easy-to-adhere layer; any known easy-to-adhere layer may be used appropriately.

[0141] In an optical film according to one embodiment of the present invention, it is preferable to provide an easy-to-adhere layer only on one side of the layer or film that serves as the base layer (base) of the light-transmitting layer B, or on both sides of the film. Among these methods, it is at least more preferable to provide an easy-to-adhere layer on the surface of the light-transmitting layer A side of the layer or film that serves as the base layer (base) of the light-transmitting layer B.

[0142] There are no particular limitations on the hard coating layer; examples include a cured layer comprising a resin containing alicyclic hydrocarbons and microparticles covered by a polymeric silane coupling agent. When a hard coating layer is provided, it is preferable to further provide a buffer layer between the hard coating layer and the film. There are no particular limitations on the buffer layer; examples include a layer comprising a resin different from the resin contained in the hard coating layer and microparticles covered by a polymeric silane coupling agent.

[0143] In an optical film according to one embodiment of the present invention, the hard coating is preferably provided only on one or both surface sides of the layer or film that serves as the base layer (foundation) of the light-transmitting layer B. Among these films, it is at least more preferable to provide the hard coating on the surface side of the layer or film that serves as the base layer (foundation) of the light-transmitting layer B opposite to the light-transmitting layer A. Furthermore, it is even more preferable to provide the hard coating only on the surface side of the layer or film that serves as the base layer (foundation) of the light-transmitting layer B opposite to the light-transmitting layer A.

[0144] The substrate layer can have only one functional layer on one or both sides, or it can have two or more layers stacked.

[0145] There is no particular limitation on the film thickness of the functional layer of the substrate layer, but it is preferably less than 10 μm, more preferably less than 8 μm, even more preferably less than 5 μm, and particularly preferably less than 3 μm (the lower limit is more than 0 μm).

[0146] (Film thickness of the substrate layer)

[0147] The thickness of the substrate layer is not particularly limited, but is preferably 10 μm or more, more preferably 20 μm or more, further preferably 30 μm or more, and particularly preferably 50 μm or more. Within this range, the protective effect of the light-transmitting layer A, the effect on imparting mechanical properties to the optical film, and the processing adaptability of the optical film are further improved. Furthermore, when the substrate layer is a light-transmitting layer B, the suppression of image quality degradation originating from the seams between the panel units in a display device having a display surface composed of multiple panel units is further improved. Additionally, the thickness of the substrate layer is preferably 500 μm or less, more preferably 200 μm or less, further preferably 100 μm or less, and particularly preferably 80 μm or less. Within this range, when the substrate layer is a light-transmitting layer, the brightness is further improved in a display device having a display surface composed of multiple panel units.

[0148] In one embodiment of the present invention, the thickness of the light-transmitting layer A is preferably thinner than the thickness of the substrate layer.

[0149] (Example of a substrate layer)

[0150] Commercially available products can be used as the substrate layer. There are no particular restrictions on commercially available products. For example, Zeonor (registered trademark) ZF16 manufactured by Zeon Co., Ltd. of Japan, and COSMO SHINE (registered trademark) A4300 manufactured by Toyobo Co., Ltd. can be used.

[0151] <Other Functional Layers>

[0152] An optical film according to one embodiment of the present invention may further have functional layers other than the light-transmitting layer A and the substrate layer, that is, other functional layers besides the functional layers of the substrate layer described above. For example, in an optical film according to one embodiment of the present invention, other functional layers may be further provided on one or both sides of the light-transmitting layer A as needed. The details of these other functional layers are also the same as those described above for the functional layers of the substrate layer.

[0153] It should be noted that in the optical film of one embodiment of the present invention, when other functional layers are provided on one or both sides of the light-transmitting layer A, the total light transmittance of the laminate of the light-transmitting layer A and the other functional layers provided on one or both sides of the light-transmitting layer A is preferably 10% to 30%, more preferably 15% to 25%. The total light transmittance can be measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K 7361-1:1997 (Test method for total light transmittance of plastics—transparent materials).

[0154] Furthermore, in an optical film according to one embodiment of the present invention, when other functional layers are provided on one or both sides of the light-transmitting layer A, when measuring the haze of a laminate of a light-transmitting layer A, a light-transmitting layer B, and other functional layers provided on one or both sides of the light-transmitting layer A, the haze value Hz(A-B) (%) when light is incident from the light-transmitting layer A side and the haze value Hz(B-A) (%) when light is incident from the light-transmitting layer B side preferably satisfy the relationship that Hz(A-B) < Hz(B-A). The haze value can be measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K 7136:2000.

[0155] <Examples of membrane composition>

[0156] Figure 1 (A) to (C) respectively represent examples of membrane configurations used in one embodiment of the present invention. Figure 1 (A) indicates a single-layer film consisting only of the light-transmitting layer A1. Additionally, Figure 1 (B) represents the laminated film 2 formed by stacking transparent layer A1 and transparent layer B3. Figure 1 In (B), a light-transmitting layer A1 forms one outermost surface, and a light-transmitting layer B3 forms another outermost surface. The light-transmitting layer B3 is disposed on the surface of the light-transmitting layer A1 in contact with the light-transmitting layer A1. Preferably, for example, the light-transmitting layer B has an easy-adhesive layer (not shown), and the light-transmitting layer B3 having the easy-adhesive layer (not shown) is disposed on the surface of the light-transmitting layer A1 in contact with the light-transmitting layer A1. Furthermore, Figure 1 (C) represents a laminated film 2 formed by stacking a light-transmitting layer A1 and a light-transmitting layer B3, wherein the light-transmitting layer B3 forms a thin film having a hard coating layer 4 on the side opposite to the side of the light-transmitting layer A1. In C of Figure (1), the outermost example constitutes a light-transmitting layer A1, and a light-transmitting layer B3 is disposed on the surface of the light-transmitting layer A1 in a manner connected to the light-transmitting layer A1. For example, it is also preferable that the light-transmitting layer B has an easy-adhesion layer (not shown), and the light-transmitting layer B3 having the easy-adhesion layer (not shown) is disposed on the surface of the light-transmitting layer A1 in a manner connected to the light-transmitting layer A1. In addition, it is also preferable, for example, that a hard coating layer 4 is formed on the easy-adhesion layer (not shown) of the light-transmitting layer B3 having the easy-adhesion layer (not shown). It should be noted that in Figure 1 In (C), 3' represents the layer or film that forms the matrix (base) of the light-transmitting layer B3.

[0157] <Membrane Manufacturing Method>

[0158] The method for manufacturing the optical film according to one embodiment of the present invention is not particularly limited, and known film manufacturing methods can be used. Examples include coating, solution casting, melt casting, and vapor phase film formation. Among these films, a method comprising the following steps is preferred: 1) a coating liquid preparation step for obtaining a coating liquid for forming a light-transmitting layer A; 2) a coating film formation step for applying the obtained coating liquid for forming a light-transmitting layer A to the surface of a support; and 3) a drying step for removing solvent from the coating film of the applied coating liquid for forming a light-transmitting layer A to form a light-transmitting layer A.

[0159] Here, when the support is a substrate layer (e.g., light-transmitting layer B), a laminated film comprising a light-transmitting layer A and a substrate layer can be manufactured using this manufacturing method.

[0160] 1) Coating solution preparation process

[0161] In this process, a coating liquid for forming transparent layer A is prepared, comprising the particles described in the above-described transparent layer A, the colorant described in the above-described transparent layer A, and a solvent. The coating liquid for forming transparent layer A may further contain a matrix material (e.g., resin) or other components as needed.

[0162] The coating liquid for forming the transparent layer A is preferably prepared by mixing the particle dispersion or solution, solvent, desired matrix material, and other desired components after preparing the particle dispersion or solution and the colorant dispersion or solution. There are no particular limitations on the preparation of the particle dispersion or colorant dispersion or solution; however, it is preferable to use the layer described below as an example of a solvent for the coating liquid for forming the transparent layer A. Furthermore, it is preferable to perform filtration during the preparation of the particle dispersion or colorant dispersion or solution. A known filtration device can be appropriately used for filtration.

[0163] There are no particular limitations on the solvents used in the coating solution for forming the transparent layer A. Examples include chlorinated solvents such as chloroform and dichloromethane, alcohols such as methanol, ethanol, propanol, n-butanol, 2-butanol, tert-butanol, and cyclohexanol, ketones such as methyl ethyl ketone, methyl isobutyl ketone, and acetone, esters such as ethyl acetate, methyl acetate, ethyl lactate, isopropyl acetate, amyl acetate, and ethyl butyrate, ethylene glycol ethers (propylene glycol mono(C1-C4)alkyl ethers (specifically propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, propylene glycol monon-propyl ether, propylene glycol monoisopropyl ether, propylene glycol monobutyl ether, etc.), propylene glycol mono(C1-C4)alkyl ether esters (propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate)), hydrocarbons such as toluene, benzene, cyclohexane, and n-hexane, etc. From the viewpoint of easily dissolving the matrix material, having a low boiling point, and easily improving drying speed and productivity, these substances preferably include chlorinated solvents, alcohols, and ketones, and more preferably include chlorinated solvents.

[0164] Furthermore, from the viewpoint of easily forming a highly planar, transparent layer A, it is preferable to include chlorinated solvents, alcohols, and ketones. As a chlorinated solvent, dichloromethane is preferred. As an alcohol, methanol or ethanol is preferred, more preferably ethanol. As a ketone, methyl ethyl ketone or acetone is preferred, more preferably methyl ethyl ketone. That is, it is particularly preferable to include at least one of dichloromethane, ethanol, and methyl ethyl ketone.

[0165] When the solvent includes chlorinated solvents and other solvents, the content ratio of chlorinated solvents is not particularly limited. From the viewpoint of balancing drying speed and planarity, a ratio of less than 100 / more than 0 to 60 / 40 (mass ratio) of chlorinated solvent / other solvent is preferred, more preferably 99.9 / 0.1 to 90 / 10 (mass ratio), and even more preferably 99.5 / 0.5 to 99 / 1 (mass ratio). If the proportion of chlorinated solvents is appropriately higher, drying performance and productivity can be easily improved.

[0166] From the viewpoint of easily adjusting the viscosity to an appropriate range, the concentration of the matrix material in the coating liquid for forming the translucent layer A is preferably 1 to 20% by mass. Furthermore, from the viewpoint of reducing shrinkage during the drying of the coating film, the concentration of the matrix material in the coating liquid for forming the translucent layer A is more preferably more than 5% by mass and less than 20% by mass, and even more preferably more than 5% by mass and less than 15% by mass.

[0167] In the preparation of various dispersions or solutions, such as coating liquids for forming transparent layer A, particle dispersions, colorant dispersions, or colorant solutions, there are no particular restrictions on the mixing conditions. As for the mixing temperature, mixing can be carried out at room temperature; however, to improve solubility, mixing can be performed while heating. Furthermore, as for the mixing time, there are no particular restrictions, but when mixing a matrix material, it is preferable to set the time until the matrix material is completely dissolved. Additionally, a known mixing apparatus can be appropriately used during mixing.

[0168] The viscosity of the coating solution for forming the light-transmitting layer A is not particularly limited, but is preferably 5 to 5000 mPa·s. If the viscosity of the coating solution for forming the light-transmitting layer A is 5 mPa·s or higher, it is easier to form a layer of suitable thickness. Furthermore, if the viscosity of the coating solution for forming the light-transmitting layer A is 5000 mPa·s or lower, it is possible to further suppress uneven thickness caused by an increase in solution viscosity. From the same viewpoint, the viscosity of the coating solution for forming the light-transmitting layer A is more preferably 100 to 1000 mPa·s. This viscosity can be measured using an E-type viscometer at 25°C.

[0169] 2) Coating film formation process

[0170] In this process, the resulting light-transmitting layer A forming coating liquid is applied to the surface of the support. Specifically, the resulting light-transmitting layer A forming coating liquid is applied to the surface of the support.

[0171] There are no particular restrictions on the coating method for the coating liquid used to form the translucent layer A; known coating methods can be used. Examples include back coating, gravure coating, spin coating, wire rod coating, and roller coating. Among these coating methods, back coating is preferred from the viewpoint of forming a thin and uniform coating film.

[0172] In the manufacture of laminated films, a substrate layer is preferably used as a support, as described above. Details of the substrate layer are as explained above. Furthermore, when using a substrate layer as a support, the substrate layer has a functional layer (e.g., an easy-to-adhere layer), and it is also preferable to apply a coating liquid for forming a light-transmitting layer A to the surface on which this functional layer is formed.

[0173] 3) Drying process

[0174] In this process, the solvent is removed from the coating film of the light-transmitting layer A formed by the coating liquid applied to the support, thereby forming the light-transmitting layer A. Specifically, the coating film of the light-transmitting layer A formed by the coating liquid applied to the support is dried.

[0175] There are no particular limitations on the coating method for the coating liquid used to form the translucent layer A, and known drying methods can be used. For example, methods using air supply or heating can be cited. Among these coating methods, from the viewpoint of easily suppressing curling, the method using air supply is preferred.

[0176] There is no particular limitation on the drying speed of the coating, but it is preferably 0.0015 to 0.05 kg / hr·m. 2 More preferably, it is 0.002–0.05 kg / hr·m 2 It should be noted that the drying rate is expressed as the mass of solvent evaporated per unit time and per unit area. The drying rate can usually be adjusted by the drying temperature. Furthermore, there are no particular limitations on the drying temperature, but it is preferably (Tb-50) to (Tb+50) °C relative to the boiling point Tb of the solvent used, for example, preferably 50 to 200 °C.

[0177] For example, after this process, by peeling the light-transmitting layer A from the support, a single-layer film consisting only of the light-transmitting layer A can be obtained.

[0178] Furthermore, for example, when using a substrate layer as a support, the result of forming the substrate layer after this process is the formation of a laminated film comprising a light-transmitting layer A and a substrate layer. In this case, the light-transmitting layer A can be used directly as a laminated film without peeling it off from the substrate layer. In particular, when the substrate layer is a light-transmitting layer B composed solely of the aforementioned base layer or film, or a light-transmitting layer B having a functional layer (e.g., an easy-to-adhere layer), the light-transmitting layer A can also be used directly as an optical film without peeling it off.

[0179] 4) Winding process

[0180] In one embodiment of the present invention, the optical film can be in the form of a strip. Therefore, the method for manufacturing the optical film may further include a winding step of winding the strip-shaped optical film into a roll.

[0181] In this process, the obtained strip-shaped light-transmitting layer A, the laminate of light-transmitting layer A and the substrate layer, or other structures that form other functional layers as needed are wound into a roll in a direction orthogonal to its width direction to form a roll.

[0182] There is no particular limitation on the length of the strip-shaped optical film, but it is preferably about 100 to 10,000 m. In addition, the width of the strip-shaped optical film is preferably more than 1 m, and more preferably 1.3 to 4 m.

[0183] <Membrane Manufacturing Apparatus>

[0184] The optical film in one embodiment of the present invention is not particularly limited; for example, it can be made of... Figure 2 The manufacturing apparatus shown is used for manufacturing.

[0185] Figure 2 This is a schematic diagram of a manufacturing apparatus 200 for manufacturing an optical film according to one embodiment of the present invention. The manufacturing apparatus 200 includes a supply section 210, a coating section 220, a drying section 230, a cooling section 240, and a winding section 250. a to d indicate the conveying rollers of the conveying support 110.

[0186] The supply unit 210 has an extraction device (not shown) for extracting the roll 201 of the strip-shaped support 110 wound around the core.

[0187] The coating section 220 is a coating apparatus, which includes a support roller 221 for holding the support body 110, a coating head 222 for coating the support body 110 held by the support roller 221 with a coating liquid for forming a light-transmitting layer A, and a pressure reducing chamber 223 provided on the upstream side of the coating head 222.

[0188] The flow rate of the coating liquid for forming the transparent layer A discharged from the coating head 222 can be adjusted by a pump (not shown). The flow rate of the coating liquid for forming the transparent layer A discharged from the coating head 222 is set to ensure that a coating layer of a specified thickness can be stably formed during continuous coating under pre-adjusted conditions of the coating head 222.

[0189] The pressure-reducing chamber 223 is a mechanism used to stabilize the droplets (accumulation of coating liquid) formed between the coating liquid for forming the transparent layer A from the coating head 222 and the support body 110 during coating, and the pressure reduction can be adjusted. The pressure-reducing chamber 223 is connected to a pressure-reducing blower (not shown) to reduce the internal pressure. The pressure-reducing chamber 223 is in a state of no air leakage, and the gap between it and the support roller is also adjusted to be narrower so that stable droplets of coating liquid can be formed.

[0190] The drying unit 230 is a drying apparatus for drying the coating film applied to the surface of the support 110, and includes a drying chamber 231, an inlet 232 for drying gas, and an outlet 233. The temperature and flow rate of the drying air are appropriately determined according to the type of coating film and the type of support 110. By setting the temperature and flow rate of the drying air, drying time, and other conditions using the drying unit 230, the residual solvent content of the dried coating film can be adjusted. The residual solvent content of the dried coating film can be determined by comparing the unit mass of the dried coating film with the mass of the coating film after thorough drying.

[0191] The cooling section 240 cools the support 110, which has a coating (transparent layer A (not shown)) dried by the drying section 230, and adjusts it to an appropriate temperature. The cooling section 240 includes a cooling chamber 241, a cooling air inlet 242, and a cooling air outlet 243. The temperature and airflow of the cooling air can be appropriately determined according to the type of coating and the type of support 110. Alternatively, the cooling section 240 can be omitted if an appropriate cooling temperature is achieved.

[0192] The winding section 250 is a winding device (not shown) for winding a support 110 (laminated body 100) having a light-transmitting layer A (not shown) to obtain a roll 251.

[0193] It should be noted that, in the case of manufacturing a laminated film, as described above, it is preferable to use a substrate layer as the support 110 (e.g., a light-transmitting layer B). In this case, the laminate 100 of the light-transmitting layer A and the support forms a laminated film.

[0194] <Uses>

[0195] An optical film according to one embodiment of the present invention is used in a display device having a display surface composed of multiple panel units. The optical film according to one embodiment of the present invention is not particularly limited, and can be preferably applied, for example, to the units listed in the detailed description of the panel units and display device below.

[0196] (Panel unit and display device)

[0197] There are no particular limitations on the panel unit that uses the optical film described above and the display device that includes the panel unit, but it is preferred to be a self-emissive panel unit and a display device having a display surface formed therefrom.

[0198] In one embodiment of the present invention, the optical film described above is more preferably used in a display device having a display surface composed of panel units having light-emitting modules. That is, another aspect of the present invention is also referred to as a panel unit, having a light-emitting module and the aforementioned optical film disposed on the side closer to the display surface (i.e., the visual recognition side in the display device) than the light-emitting module, for use in a display device having a display surface composed of multiple panel units.

[0199] In another embodiment of the present invention, when the optical film comprises the light-transmitting layer A and the substrate layer (preferably the light-transmitting layer B), and the substrate layer (preferably the light-transmitting layer B) is disposed on the display surface side of the light-transmitting layer A, the optical film is more preferably used in a display device having a display surface composed of panel units having light-emitting modules. That is, another aspect of the present invention may also be referred to as a panel unit, which has a light-emitting module and the optical film disposed on the display surface side of the light-emitting module, and is used in a display device having a display surface composed of a plurality of panel units on the display surface side of the light-transmitting layer A. In this case, it is preferable that the light-transmitting layer A constitutes one of the outermost surfaces of the optical film, and the surface of the optical film disposed on the side of the light-transmitting layer A faces the light-emitting module.

[0200] In one embodiment of the present invention, the panel unit is not particularly limited; for example, a panel unit having a known light-emitting module can be used. Among these units, it is preferable to have a light-emitting module in which numerous tiny light-emitting elements are mounted in a matrix on a wiring substrate, and each light-emitting element is selectively made to emit light by a light-emitting control mechanism connected thereto. This allows visual information to be directly displayed on the display screen through the flickering of each light-emitting element. Furthermore, the light-emitting elements included in the light-emitting module are more preferably LED elements. That is, the light-emitting module is more preferably an LED module in which the light-emitting elements are LED elements.

[0201] When the panel unit includes a light-emitting module and the aforementioned optical film, it is preferable to bond the light-emitting module and the aforementioned optical film using an adhesive. Preferably, when bonding the laminated film, the aforementioned substrate layer (preferably the light-transmitting layer B) is disposed on the display surface side further than the aforementioned light-transmitting layer A. Furthermore, it is preferable to bond the light-emitting module and the outermost surface of the laminated film that is closer to the aforementioned light-transmitting layer A than the aforementioned substrate layer (preferably the light-transmitting layer B) on the side of the aforementioned light-transmitting layer A using an adhesive. In this case, it is preferable that the light-transmitting layer A constitutes one of the outermost surfaces of the optical film, and the surface of the optical film with the light-transmitting layer A side is bonded to the light-emitting module in a manner opposite to each other. There are no particular limitations on the adhesive used; known adhesives can be used, such as pressure-sensitive adhesives, thermosetting adhesives, and photocurable adhesives. Among these adhesives, pressure-sensitive adhesives are preferred. There are no particular limitations on the pressure-sensitive adhesive used; examples include acrylic-based pressure-sensitive adhesives, rubber-based pressure-sensitive adhesives, silicone-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, and polyacrylamide-based pressure-sensitive adhesives. In these cases, the panel unit includes a light-emitting module, the aforementioned optical film, and an adhesive layer disposed between them.

[0202] Furthermore, when the panel unit includes a light-emitting module and the aforementioned optical film, the light-emitting module, the aforementioned optical film, and other components as needed can be integrally bonded using a hot stamping process. In the case of bonding the laminated film, the aforementioned substrate layer (preferably light-transmitting layer B) is disposed on the display surface side further than the aforementioned light-transmitting layer A. Preferably, the light-emitting module is bonded to the outermost surface of the laminated film on the side of the aforementioned light-transmitting layer A, which is further than the aforementioned substrate layer (preferably light-transmitting layer B) on the aforementioned light-transmitting layer A side. In this case, the light-transmitting layer A constitutes one of the outermost surfaces of the optical film, and preferably, the surface of the optical film on the light-transmitting layer A side is bonded to the light-emitting module in a manner where they face each other. In the case of integral bonding using a hot stamping process, the aforementioned adhesive can be applied between any components.

[0203] The following shows an example of the configuration of an LED module as one type of light-emitting module, wherein the LED module that can be used in the present invention is not limited to this configuration.

[0204] An LED module is constructed by mounting one or more LED elements on a wiring substrate formed by forming wiring portions on a support substrate. Here, it is preferable that the LED module is constructed by mounting multiple LED elements.

[0205] A wiring substrate is a circuit board formed on the surface of a support substrate in a form that allows it to conduct electricity to LED elements. For example, it may have wiring portions formed by metals such as copper or other conductive components. There are no particular limitations on the material of the support substrate; for example, conventionally known materials used as substrates for electronic circuits, such as glass epoxy resin, can be cited.

[0206] In an LED module, LED components are mounted in a manner that allows them to conduct electricity through the wiring section via an adhesive layer.

[0207] LED elements are independently controlled to emit light through additional light-emitting control mechanisms such as IC chip substrates.

[0208] There are no particular restrictions on the size of the LED module. Generally speaking, from a cost-effectiveness point of view, it is preferable that the diagonal length is about 10 inches to 200 inches, and more preferably about 50 inches to 200 inches.

[0209] There are no particular limitations on the LED element mounted on the wiring substrate, but a light-emitting element that emits light using a PN junction formed by bonding P-type and N-type semiconductors is preferred. There are no particular limitations on the structure of such a light-emitting element; for example, structures with P-type and N-type electrodes on the top or bottom of the element, or structures with P-type and N-type electrodes on only one side of the element, are examples. A particularly preferred method is to use a miniature LED element such as the one disclosed in Japanese Patent Application Publication No. 2006-339551 as a "chip-like electronic component." The LED element disclosed in that document has a width × depth × height dimension of approximately 25 μm × 15 μm × 2.5 μm.

[0210] LED components preferably include an LED light-emitting chip and a cover covering the chip. There are no particular limitations on the material of the resin cover; examples include organic insulating materials such as epoxy resin, silicone resin, and polyimide resin. Among these components, epoxy resin is preferred from the viewpoint of protecting the LED light-emitting chip from physical impacts and suppressing total internal reflection of light into the semiconductor caused by the difference in refractive index between the semiconductor constituting the LED light-emitting chip and air, thereby improving the luminous efficiency of the LED component.

[0211] The LED element is more preferably a "micro-sized LED element". In this specification, "micro-sized LED element" specifically refers to an LED element whose overall dimensions, including the LED light-emitting chip and the resin cover covering the chip, have a width (W) and depth (D) of 300 μm or less, and a height (H) of 200 μm or less. Furthermore, a "micro-sized LED element" is more preferably one with a width and depth of 50 μm or less, and a height of 10 μm or less. Additionally, the spacing between LED elements is preferably 0.03 mm to 100 mm, more preferably 0.05 mm to 5 mm. Moreover, micro-sized LED elements, where the light-emitting module (LED module) has a width and depth of 50 μm or less and a height of 10 μm or less, are particularly preferably arranged in a matrix at a spacing of several μm to tens of μm, in numbers of several thousand × several thousand or more. It should be noted that, in this specification, a display device having a display surface composed of panel units comprising LED modules arranged in a matrix at intervals of 0.03 mm to 100 mm, including the aforementioned "micro-sized LED elements", is referred to as a "Micro-LED display device".

[0212] Figure 3 This is a schematic diagram showing the cross-sectional structure of a panel unit according to one embodiment of the present invention. Figure 3The upper part becomes the display surface side (i.e., the visual recognition side of the display device). The panel unit 10 has an LED module 11 and a laminated film 2 with a hard coating 4. The laminated film 2 is positioned closer to the display surface side than the light-emitting module 11, and a light-transmitting layer B3 is positioned closer to the display surface side than the light-transmitting layer A1. At this time, the surfaces of the LED module 11 and the light-transmitting layer A1 side of the laminated film 2 are bonded together via an adhesive layer 12. It should be noted that in Figure 3 In the text, 3' represents the layer or film that forms the matrix (base) of the light-transmitting layer B3.

[0213] Display devices are devices that display visual information such as text, images, and animations. There are no particular limitations on the display device using the aforementioned optical film; known devices can be used, such as non-emissive devices like liquid crystal displays, self-emissive devices like LED displays, and organic EL displays. Among these devices, self-emissive devices are preferred, LED displays are more preferred, and Micro-LED displays mentioned above are even more preferred.

[0214] Each panel unit having a light-emitting module is preferably used in a display device having a display surface composed of multiple panel units. That is, another aspect of the present invention relates to a display device having a display surface composed of multiple panel units including the aforementioned optical film.

[0215] It should be noted that in this specification, a display device having a display surface composed of multiple panel units is referred to as an independent modular display device. In an independent modular display device, the multiple panel units can be arranged in a curved shape, or in a tile-like shape (matrix shape, flat shape). A tile-like shape is preferred. Furthermore, each display surface of the multiple panel units can constitute independent visual information, or the multiple display surfaces can constitute a single visual information as a whole. Preferably, the multiple display surfaces constitute a single visual information as a whole.

[0216] Figure 4 This is a schematic diagram illustrating the planar structure of a modular display device according to one embodiment of the present invention. The display surface of the modular display device 20 is composed of a plurality of panel units 10 laid out in a tile-like (planar) shape. Furthermore, the display device having a display surface composed of a plurality of panel units is preferably decomposable into a display device having a display surface composed of one or more of the included panel units.

[0217] It should be noted that, for example, modules and devices known as those described in Japanese Patent Application Publication No. 2019-204905 may also be used as light-emitting modules and display devices.

[0218] Example

[0219] The effects of the present invention are illustrated by the following examples and comparative examples. However, the scope of the present invention is not limited to the following examples.

[0220] <Membrane Manufacturing>

[0221] [Membrane 1 (Laminated Membrane)]

[0222] (Preparation of particle dispersion)

[0223] Ten parts by mass of silica particles (AEROSIL Co., Ltd., Japan, R972V) and 90 parts by mass of ethanol were stirred and mixed in a dissolver for 30 minutes. The mixture was then dispersed using a Manton Gorlin high-pressure disperser to prepare a dispersion. To the obtained dispersion, 65 parts by mass of dichloromethane were added while stirring, and the mixture was stirred and mixed in a dissolver for 30 minutes to dilute the particles. The resulting solution was filtered through an ADVANTECH Toyo Co., Ltd., polypropylene wound cartridge filter TCW-PPS-1N to obtain the particle dispersion.

[0224] (Preparation of pigment dispersion)

[0225] Ten parts by weight of carbon black (CB) (Mitsubishi Chemical Corporation #950) and 90 parts by weight of methyl ethyl ketone (MEK) were mixed in a solvent and stirred for 30 minutes. The mixture was then dispersed using an ultrasonic disperser for 30 minutes to prepare a dispersion. The resulting dispersion was filtered using an ADVANTECH Toyo Co., Ltd. TCW-PPS-1N polypropylene wound cartridge filter to obtain a pigment dispersion.

[0226] (Preparation of coating solution for forming translucent layer A)

[0227] First, dichloromethane is added to a pressurized dissolving vessel. Then, while stirring, a cyclic olefin resin (COP, weight-average molecular weight 140,000, polar group (carboxyl group), manufactured by JSR Corporation, ARTON (registered trademark) G7810) is added. Next, the particle dispersion and pigment dispersion prepared above are added, and the mixture is heated to 60°C and stirred for 30 minutes to completely dissolve the cyclic olefin resin, yielding a coating solution for forming the translucent layer A.

[0228] Composition of the coating solution for forming the light-transmitting layer A

[0229]

[0230] (Fabrication of a laminated film including transparent layer A and transparent layer B)

[0231] As the light-transmitting layer B, Zeonor ZF16 (manufactured by Zeon Corporation of Japan, 100 μm thick) was prepared. The coating liquid for forming the light-transmitting layer A obtained above was applied to this light-transmitting layer B using a back-coating method with a mold. Then, it was dried at a rate of 0.002 kg / hr·m. 2 The transparent layer A is dried at 130°C by hot air blown in from the side of the transparent layer B and hot air blown in from the side of the coating liquid used to form the transparent layer A, forming a transparent layer A with a thickness of 10 μm, thus obtaining film 1 as a laminated film. It should be noted that the average secondary particle size of the silica particles in the transparent layer A is 200 nm, and the average secondary particle size of the pigment is 300 nm.

[0232] [Membrane 2 (Laminated Membrane)]

[0233] In the manufacture of membrane 1, the light-transmitting layer B is changed to a polyethylene terephthalate (PET) membrane (COSMOSHINE (registered trademark) A4300 manufactured by Toyobo Co., Ltd., with a thickness of 50 μm), and membrane 2, which is a laminated membrane, is obtained in the same way.

[0234] [Membrane 3 (Laminated Membrane)]

[0235] In the manufacture of membrane 1, the amount of carbon black added to the light-transmitting layer A is changed to 0.55 parts by mass relative to 100 parts by mass of the cyclic olefin resin, and membrane 3 is obtained as a laminated membrane in the same manner.

[0236] [Membrane 4 (Laminated Membrane)]

[0237] In the manufacture of membrane 1, the amount of carbon black added to the light-transmitting layer A was changed to 0.55 parts by mass relative to 100 parts by mass of the cyclic olefin resin, and the amount of pigment dispersion added was changed to the light-transmitting layer B to a polyethylene terephthalate (PET) membrane (COSMOSHINE (registered trademark) A4300 manufactured by Toyobo Co., Ltd., with a thickness of 50 μm). Otherwise, membrane 4 as a laminated membrane was obtained in the same way.

[0238] [Membrane 5 (Laminated Membrane)]

[0239] In the manufacture of membrane 1, the amount of carbon black added to the light-transmitting layer A was changed to 0.50 parts by mass relative to 100 parts by mass of the cyclic olefin resin, and the amount of pigment dispersion added was changed to the light-transmitting layer B to a polyethylene terephthalate (PET) membrane (COSMOSHINE (registered trademark) A4300 manufactured by Toyobo Co., Ltd., with a thickness of 50 μm). Otherwise, membrane 5 as a laminated membrane was obtained in the same way.

[0240] [Membrane 6 (Laminated Membrane)]

[0241] In the manufacture of membrane 1, the amount of carbon black added to the light-transmitting layer A is changed to 0.50 parts by mass relative to 100 parts by mass of the cyclic olefin resin, and otherwise membrane 6 is obtained as a laminated membrane.

[0242] [Membrane 7 (Single-layer membrane)]

[0243] In the manufacture of membrane 1, the amount of carbon black added to the transparent layer A is varied by changing the amount of pigment dispersion added to 0.55 parts by mass relative to 100 parts by mass of cyclic olefin resin. Otherwise, a laminated membrane comprising transparent layer A and transparent layer B is obtained. Next, by peeling transparent layer B from the obtained laminated membrane to obtain only transparent layer A, membrane 7, as a monolayer membrane, is obtained.

[0244] [Membrane 8 (Laminated Membrane)]

[0245] In the manufacture of membrane 1, no particle dispersion is added during the manufacture of transparent layer A. The amount of carbon black added to transparent layer A is changed to 0.55 parts by mass relative to 100 parts by mass of cyclic olefin resin. Transparent layer B is changed to polyethylene terephthalate membrane (PET membrane) (COSMOSHINE (registered trademark) A4300 manufactured by Toyobo Co., Ltd., thickness 50 μm). Otherwise, membrane 8 as a laminated membrane is obtained in the same way.

[0246] [Membrane 9 (Single-layer membrane)]

[0247] In the manufacture of membrane 1, no particle dispersion is added during the manufacture of the transparent layer A. The amount of pigment dispersion is varied such that the amount of carbon black added to the transparent layer A is 0.55 parts by mass relative to 100 parts by mass of the cyclic olefin resin. Otherwise, a laminated membrane comprising transparent layer A and transparent layer B is obtained. Next, transparent layer B is peeled off from the obtained laminated membrane to form transparent layer A only, thereby obtaining membrane 9 as a monolayer membrane.

[0248] [Membrane 10 (Laminated Membrane)]

[0249] In the manufacture of membrane 1, the amount of pigment dispersion added is changed such that the amount of carbon black added to the light-transmitting layer A is 0.65 parts by mass relative to 100 parts by mass of cyclic olefin resin. Otherwise, membrane 10 as a laminated membrane is obtained in the same way.

[0250] [Membrane 11 (Laminated Membrane)]

[0251] In the manufacture of membrane 1, no pigment dispersion is added during the manufacture of the light-transmitting layer A, and membrane 11, which is a laminated membrane, is obtained in the same way.

[0252] It should be noted that in all of the above-mentioned films 2 to 11, the thickness of the light-transmitting layer A is 10 μm. Furthermore, in all of the above-mentioned films 2 to 11, except for films 8 and 9 which do not contain silica particles, the average secondary particle size of the silica particles in the light-transmitting layer A is 200 nm. Also, in all of the above-mentioned films 2 to 11, except for film 11 which does not contain pigments, the average secondary particle size of the pigments is 300 nm.

[0253] The characteristics of each membrane are shown in Table 1 below.

[0254] <Membrane Evaluation>

[0255] [Total light transmittance of light-transmitting layer A and light-transmitting layer B]

[0256] For membranes 1-6, 8, 10, and 11, which are laminated membranes, after stripping the light-transmitting layer B and leaving only the light-transmitting layer A, the total light transmittance (%) of membranes 7 and 9, which are monolayer membranes, was directly evaluated in this state (i.e., in the state of only the light-transmitting layer A). These results are shown in Table 1 below.

[0257] In addition, the total light transmittance of Zeonor (registered trademark) ZF16 manufactured by Zeon Co., Ltd. of Japan and COSMOSHINE (registered trademark) A4300 manufactured by Toyobo Co., Ltd., which were used as the light transmittance layer B, was measured using the same method and was 91.90% and 90.41%, respectively.

[0258] It should be noted that the total light transmittance was measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K 7361-1:1997 (Test method for total light transmittance of plastics - transparent materials).

[0259] [Haze of laminated films]

[0260] For films 1 to 6, 8, 10, and 11, which are laminated films, the haze values ​​Hz(A-B) (%) measured from the light-transmitting layer A side and the haze values ​​Hz(B-A) (%) measured from the light-transmitting layer B side were evaluated. The haze values ​​were measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) based on JIS K 7136:2000. The larger value between Hz(A-B) (%) and Hz(B-A) (%) is shown in Table 1 below.

[0261] <Evaluation of Display Devices>

[0262] [Manufacturing of panel units and display devices]

[0263] An adhesive layer made of pressure-sensitive adhesive is bonded to the surface of the resin cover of the LED elements in an LED module, which has an overall shape of 40cm in length and 40cm in width and contains LED elements with a spacing of 2mm in both directions. Next, the obtained film is bonded to the aforementioned surface of the LED elements in the LED module via this adhesive layer to obtain a panel unit. Here, when the film is a laminated film, it is bonded with the light-transmitting layer A side of the laminated film facing each other to the aforementioned surface of the LED elements. Furthermore, two panel units are horizontally connected side-by-side to obtain an independent modular display device.

[0264] [Brightness and seamlessness of the display device]

[0265] For the aforementioned modular display device, the luminance (cd / m²) was measured using a ProMetric Color 1600 manufactured by CYBERNET SYSTEMS Co., Ltd. 2 The average brightness and brightness uniformity of the panel units are evaluated. Here, the higher the seamlessness between panels in terms of brightness uniformity, the smaller this value. Therefore, brightness uniformity can be considered an indicator of the suppression effect on image quality degradation originating from the seams between panel units in a display device having a display surface composed of multiple panel units. The average brightness and brightness uniformity can be calculated using the following formulas. In the following formulas, average uniformity is expressed as Lu, and average brightness is expressed as La.

[0266] It should be noted that, except for the panel unit without the aforementioned film, the average brightness of the stand-alone modular display manufactured in the same manner as described above is 3000 cd / m². 2 .

[0267] [Number 1]

[0268] Average brightness La = (L1 + L2) / 2

[0269] Brightness uniformity Lu=(|L1-L2| / La)×100

[0270] L1: The average brightness of two panel units for the three points between the center and points 10cm above and below the center within each panel unit.

[0271] L2: The average brightness of three points: the center of two adjacent panel units and points located 10cm above and below the center.

[0272] It should be noted that for brightness, ratings A to C are considered good. These results are shown in Table 1 below.

[0273] (Brightness evaluation criteria)

[0274] A: The average brightness is 1000 (cd / m²). 2 )above,

[0275] B: Average brightness is 500 (cd / m²) 2 Above and below 1000 (cd / m 2 ),

[0276] C: Average brightness is 200 (cd / m²) 2 ) or more and less than 500 (cd / m 2 ),

[0277] D: Average brightness less than 200 (cd / m²) 2 ).

[0278] Furthermore, for seamlessness, evaluations A through C were deemed to indicate good results. These results are shown in Table 1 below.

[0279] (Evaluation criteria for seamlessness)

[0280] A: Brightness uniformity is below 6.

[0281] B: Brightness uniformity exceeding 6 but below 12

[0282] C: Brightness uniformity exceeding 12 but below 18

[0283] D: Brightness uniformity exceeds 18.

[0284]

[0285] As can be confirmed from Table 1 above, the display devices using films 1 to 7 of the present invention exhibit excellent seamlessness and brightness. On the other hand, it is confirmed that films 8 and 9 of the comparative examples, which do not have particles in their light-transmitting layer A, have poor seamlessness. Furthermore, it is confirmed that the display devices using films 10 and 11, whose total light transmittance of the light-transmitting layer A is outside the scope of the present invention, have insufficient seamlessness or brightness.

[0286] Furthermore, a comparison of films 1, 3, and 6, as well as films 2, 4, and 5, confirmed that a better balance between seamlessness and brightness is achieved when the total light transmittance is in the range of 15–25%.

[0287] Furthermore, a comparison of films 3, 4, and 7 confirms that the laminated films satisfy the relationship Hz(A-B) < Hz(B-A), further improving seamlessness. Additionally, a comparison of films 1 and 2, and films 6 and 5, confirms that the laminated films satisfy the relationship Hz(A-B) < Hz(B-A), further improving seamlessness.

[0288] This application is based on Japanese Patent Application No. 2020-117339, filed on July 7, 2020, the entire disclosure of which is incorporated herein by reference.

[0289] Symbol Explanation

[0290] 1: Translucent layer A

[0291] 2: Laminated film

[0292] 3: Translucent layer B

[0293] 3': The layer or film that forms the matrix (base) of the light-transmitting layer B.

[0294] 4: Hard coating

[0295] 10: Panel Unit

[0296] 11: LED Module

[0297] 12: Adhesive layer

[0298] 20: Independent modular display device

[0299] 100: Laminated body (laminated film)

[0300] 110: Support (e.g., substrate layer such as light-transmitting layer B)

[0301] 200: Manufacturing equipment

[0302] 201: Roll of support (e.g., substrate layer such as light-transmitting layer B).

[0303] 210: Supply Department

[0304] 220: Coating Section

[0305] 221: Support roller

[0306] 222: Coating head

[0307] 223: Decompression Chamber

[0308] 230: Drying section

[0309] 231: Drying Chamber

[0310] 232: Inlet for drying gas

[0311] 233: Discharge outlet

[0312] 240: Cooling section

[0313] 241: Cooling Chamber

[0314] 242: Cooling air inlet

[0315] 243: Cooling air outlet

[0316] 250: Winding section

[0317] 251: Rolls of laminated bodies (laminated films)

[0318] a, b, c, d: Conveyor rollers

Claims

1. An optical film comprising a light-transmitting layer containing particles and a colorant, having a total light transmittance of 10% to 30%. A display device for having a display surface composed of multiple panel units. The light-transmitting layer is light-transmitting layer A, and the optical film further includes a substrate layer. The substrate layer is a light-transmitting layer B. The light-transmitting layer B is disposed on the light-transmitting layer A. When measuring the haze of a stack of light-transmitting layers A and B, the haze values ​​Hz(A-B) (%) when light is incident from the side of light-transmitting layer A and the haze values ​​Hz(B-A) (%) when light is incident from the side of light-transmitting layer B satisfy the relationship Hz(A-B) < Hz(B-A).

2. The optical film according to claim 1, wherein, The light-transmitting layer is a resin film.

3. The optical film according to claim 1 or 2, wherein, The total light transmittance of the light-transmitting layer is 15% to 25%.

4. The optical film according to any one of claims 1 to 3, wherein, The particles are inorganic oxide particles.

5. The optical film according to any one of claims 1 to 4, wherein, The colorant is a pigment.

6. The optical film according to claims 1 to 5, wherein, The substrate layer is a resin film.

7. A panel unit comprising a light-emitting module and an optical film according to any one of claims 1 to 5, wherein the optical film is disposed at a position closer to the display surface than the light-emitting module. A display device for having a display surface composed of multiple panel units.

8. A panel unit comprising a light-emitting module and an optical film according to any one of claims 1 to 6, wherein the optical film is disposed at a position closer to the display surface than the light-emitting module. The substrate layer is disposed at a position closer to the display surface than the light-transmitting layer A. A display device for having a display surface composed of multiple panel units.

9. The panel unit according to claim 7 or 8, wherein, The light-emitting module includes LED elements.

10. The panel unit according to claim 9, wherein, The LED element has an LED light-emitting chip and a resin cover covering the LED light-emitting chip. The width W and depth D of the LED element are both less than 300 μm, and the height H of the LED element is less than 200 μm. The spacing between each LED element is 0.03mm to 100mm.

11. A display device having a display surface composed of a plurality of panel units as described in any one of claims 7 to 10.

Images