WO2022009581A1

WO2022009581A1 - Optical film, panel unit, and display device

Info

Publication number: WO2022009581A1
Application number: PCT/JP2021/021596
Authority: WO
Inventors: 光星島田; 博紀梅田
Original assignee: コニカミノルタ株式会社
Priority date: 2020-07-07
Filing date: 2021-06-07
Publication date: 2022-01-13
Also published as: KR20230019204A; CN115812168A; JP7276613B2; TW202212936A; JPWO2022009581A1; JP2023106441A; TWI780774B

Abstract

The present invention provides a means that makes it possible to achieve both an effect of suppressing a decrease in video quality resulting from a joint between panel units and sufficient brightness in a display device having a display surface composed of a plurality of panel units. The present invention relates to a film used in a display device having a display surface composed of a plurality of panel units, the film containing particles and a coloring agent, having a total light transmittance of 10-30%, and including a light transmissive layer.

Description

Optical film, panel unit, and display device

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

As a next-generation display device that replaces various liquid crystal display devices, Japanese Patent Application Laid-Open No. 2018-14481 (US Patent Application Publication No. 2018/0019233, US Patent Application Publication No. 2018/0331085, or Development of a self-luminous display device typified by a micro LED display device as described in US Pat. No. 6,2018,0331086) is underway.

In such a self-luminous display body, in order to avoid adversely affecting the image quality in which the light reflected on the substrate or the like on which the light emitting element serving as a light source is mounted is displayed, the light blocking effect absorbs visible light. It is being studied to stack the layers on the display surface side of the light emitting module including the light emitting element.

Japanese Patent Application Laid-Open No. 2019-204905 describes a light emitting module in which a plurality of light emitting elements are mounted on a wiring substrate, and a black encapsulant having an olefin-based resin as a base resin and having a visible light transmittance of 5% or more and 70% or less. A self-luminous display body including a sheet and a transparent optical layer (translucent layer) is disclosed. In the self-luminous display body, the black encapsulant sheet covers the surface of the light emitting element and the wiring board and is laminated on the light emitting module, and the transparent optical layer is laminated on the black encapsulant sheet. Further, in the document, such a black encapsulant sheet exhibits good characteristics as a light-shielding layer, and the layer structure of the self-luminous display body is simplified as compared with the conventional self-luminous display body. As a result, it is disclosed that the productivity of the self-luminous display can be improved.

According to Japanese Patent Application Laid-Open No. 2019-204905, when used in a display device having a display surface composed of a plurality of panel units, the image quality derived from the joint between the panel units is obtained. It is possible to suppress the decrease. However, the display device using the black encapsulant sheet according to JP-A-2019-204905 has a problem that the brightness is greatly reduced.

Therefore, the present invention provides means for a display device having a display surface composed of a plurality of panel units, capable of suppressing deterioration of image quality due to a joint between the panel units and achieving both sufficient brightness. The purpose is to provide.

The above problem of the present invention can be solved by the following means.

A translucent layer containing particles and a colorant and having a total light transmittance of 10% or more and 30% or less.
An optical film used in a display device having a display surface composed of a plurality of panel units.

(A) to (C) are schematic views showing the cross-sectional structure of the optical film used in one embodiment of the present invention, respectively. 1 is a translucent layer A described later, 2 is a laminated film, 3 is a translucent layer B described later, 3'is a layer or film that serves as a base (base) of the translucent layer B, and 4 is. Each hardcourt layer is represented. It is a schematic diagram which shows an example of the manufacturing apparatus of the optical film which concerns on one Embodiment of this invention. 100 is a laminated body (laminated film), 110 is a support (for example, a base material layer such as a translucent layer B), 200 is a manufacturing apparatus, and 201 is a support (for example, a translucent layer B or the like). The roll body of the base material layer), 210 is a supply part, 220 is a coating part, 221 is a backup roll, 222 is a coating head, 223 is a decompression chamber, 230 is a drying portion, and 231 is a drying chamber. 232 is a drying gas inlet, 233 is a discharge port, 240 is a cooling section, 241 is a cooling chamber, 242 is a cooling air inlet, 243 is a cooling air outlet, and 250 is a winding section. 251 represents a roll body of a laminated body (laminated film), and a, b, c, and d represent a transport roll. It is a schematic diagram which shows the cross-sectional structure of the panel unit which concerns on one Embodiment of this invention. 1 is a translucent layer A described later, 2 is a laminated film, 3 is a translucent layer B described later, 3'is a layer or film that serves as a base (base) of the translucent layer B, and 4 is. 10 represents a panel unit, 11 represents an LED module, and 12 represents an adhesive layer. It is a schematic diagram which shows the planar structure of the independent module type display apparatus which concerns on one Embodiment of this invention. 10 represents a panel unit, and 20 represents an independent modular display device.

In the present specification, "XY" indicating a range means "X or more and Y or less". Unless otherwise specified, the operation, physical properties, etc. are measured under the conditions of room temperature (20 to 25 ° C.) / relative humidity of 40 to 50% RH.

Further, in the present specification, the (co) polymer is a general term including a copolymer and a homopolymer.

And, in this specification, "(meth) acrylate" is a general term for acrylate and methacrylate. Similarly, compounds containing (meta) such as (meth) acrylic acid are a general term for compounds having "meta" in the name and compounds having no "meta".

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings as necessary. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted. In addition, the dimensional ratios in the drawings are exaggerated for convenience of explanation and may differ from the actual ratios.

<Translucent layer A>
One aspect of the present invention is a display device having a display surface composed of a plurality of panel units, including particles and a colorant, having a total light transmittance of 10% or more and 30% or less, and including a translucent layer. With respect to the optical film used. According to one aspect of the present invention, in a display device having a display surface composed of a plurality of panel units, it is possible to achieve both an effect of suppressing deterioration of image quality derived from a joint between the panel units and sufficient brightness. Means can be provided.

In addition, in this specification, a layer containing particles and a colorant and having a total light transmittance of 10% or more and 30% or less is also referred to as a translucent layer A.

The present inventors presume the mechanism by which the problem is solved by the present invention as follows.

In a display device having a display surface composed of a plurality of panel units, when external light is incident inside the device, the external light is reflected by a substrate or the like on which a light emitting element as a light source is mounted, and reflected light is generated. .. Then, at the joint between the panel units, for example, the reflected light is reflected or refracted on the side surface of the adjacent panel unit and then emitted to the display surface side, so that local scattering of light is visually recognized. It will be. Then, such local scattering of light causes deterioration of the image quality resulting from the joint between the panel units.

Since the black encapsulant sheet according to JP-A-2019-204905 has a function of absorbing visible light, it absorbs and displays the reflected light reflected by a substrate or the like on which a light emitting element as a light source is mounted. The reflected light toward the surface side is reduced, and the scattered light emitted is also reduced. As a result, the deterioration of the image quality caused by the joint between the panel units is suppressed. However, since the black encapsulant sheet according to JP-A-2019-204905 absorbs most of the emitted light emitted from the light emitting element as a light source, the panel unit or the display device provided with such a sheet has a high luminance. It drops significantly.

On the other hand, in the present invention, the translucent layer A contains a colorant and has a total light transmittance of 10% or more and 30% or less. Since the translucent layer A has a function of absorbing visible light in an appropriate range, it absorbs the reflected light reflected by a substrate or the like on which a light emitting element as a light source is mounted and reflects toward the display surface side. It reduces the light and also reduces the emitted scattered light. In addition, the amount of absorbed light emitted from the light emitting element serving as a light source is also equal to or less than a certain amount. From these facts, sufficient brightness can be obtained in the panel unit or the display device provided with the optical film according to the present invention. Further, in the present invention, the translucent layer A contains particles. Since the particles scatter the reflected light as a whole reflected by the substrate on which the light emitting element that is the light source is mounted, even if the light is scattered at the joint between the panel units, only that part is scattered. Light scattering is less noticeable than when local light scattering occurs. Further, since the emitted light emitted from the light emitting element serving as a light source is also scattered to some extent, the light scattering becomes less noticeable even when the light is scattered at the joint between the panel units.

The above mechanism is based on speculation, and its correctness does not affect the technical scope of the present invention.

(Base material)
The translucent layer A according to the embodiment of the present invention preferably contains a base material. The base material imparts self-support to the film and acts to retain the particles in the film.

The content of the base material is not particularly limited, but from the viewpoint of light transmission, it is preferably more than 50% by mass and more than 80% by mass with respect to the total mass of the translucent layer A. More preferably, it is more than 90% by mass. Further, the content of the base material is preferably less than 100% by mass with respect to the total mass of the translucent layer A from the viewpoint of light absorption and light scattering.

The base material is not particularly limited and may be an inorganic material or an organic material, but an organic material is preferable.

Further, the translucent layer A is preferably a translucent resin layer such as a resin film. The translucent resin layer represents a translucent layer containing a resin as a base material, and the resin film represents a film containing a resin as a base material. The resin as the base material is not particularly limited, and is, for example, an acrylic resin (for example, methyl methacrylate-methyl acrylate copolymer resin, etc.), a polycarbonate resin, a polyolefin resin (for example, a polyethylene resin, a polypropylene resin, etc.), a cycloolefin resin. (COP), polyimide resin, cellulose resin (for example, cellulose triacetate, cellulose diacetate, cellulose acetate propionate, etc.), polyester resin (for example, polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT), polybutylene terephthalate (for example). PBT), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), etc.) and the like. Among these, a cycloolefin resin is preferable from the viewpoint of haze value and optical uniformity, and a cycloolefin resin having a polar group is more preferable from the viewpoint of dispersibility of inorganic particles and colorants (particularly pigments). Examples of polar groups include a carboxy group, a hydroxy group, an alkoxycarbonyl group, an allyloxycarbonyl group, an amino group, an amide group, a cyano group, a group in which these groups are bonded via a linking group such as a methylene group, and a carbonyl group. , A hydrocarbon group to which a divalent organic group having a polarity such as an ether group, a silyl ether group, a thioether group and an imino group is bonded as a linking group is included. Among these, a cycloolefin resin having a carboxy group is preferable. When the polar group is a group capable of forming a salt, the polar group may form a salt.

The cycloolefin resin is not particularly limited, but is preferably a (co) polymer of a cycloolefin monomer represented by the following general formula (A).

Each R of the general formula (A) independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a polar group. Further, a and b in the general formula (A) independently indicate integers of 0 or more.

Further, the cycloolefin resin is more preferably a (co) polymer of a cycloolefin monomer represented by the following general formula (A-1) or the following general formula (A-2).

First, the cycloolefin monomer represented by the general formula (A-1) will be described.

^{R 1} to R ⁴ of the general formula (A-1) independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, or a polar group. However, ^{except when all of R 1} to R ⁴ are hydrogen atoms, it is assumed that R ¹ and R ² are not hydrogen atoms at the same time, or R ³ and R ⁴ are hydrogen atoms at the same time.

The halogen atom is not particularly limited, but is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. The hydrocarbon group having 1 to 30 carbon atoms is not particularly limited, but is preferably an alkyl group having 1 to 30 carbon atoms. The polar group is not particularly limited, but is a carboxy group, a hydroxy group, an alkoxycarbonyl group, an allyloxycarbonyl group, an amino group, an amide group, a cyano group, a group in which these groups are bonded via a linking group such as a methylene group, and the like. It is preferably a hydrocarbon group to which a divalent organic group having a polarity such as a carbonyl group, an ether group, a silyl ether group, a thioether group or an imino group is bonded as a linking group. Among these, a carboxy group, a hydroxy group, an alkoxycarbonyl group, or an allyloxycarbonyl group is more preferable. Further, from the viewpoint of ensuring solubility during solution film formation, an alkoxycarbonyl group or an allyloxycarbonyl group is more preferable.

At ^{least one of R 1} to R ⁴ is preferably a polar group from the viewpoint of ensuring the solubility of the cycloolefin resin during solution film formation.

P in the general formula (A-1) indicates an integer of 0 to 2. From the viewpoint of increasing the heat resistance of the film, p is preferably 1 to 2. This is because when p is 1 to 2, the obtained resin becomes bulky and the glass transition temperature tends to improve.

Next, the cycloolefin monomer represented by the general formula (A-2) will be described.

^{R 5} of the general formula (A-2) represents a hydrogen atom, a hydrocarbon group having 1 to 5 carbon atoms, or an alkylsilyl group having an alkyl group having 1 to 5 carbon atoms. Among them, R ⁵ is preferably a hydrocarbon group having 1 to 3 carbon atoms.

^{R 6} in the general formula (A-2) represents a polar group or a halogen atom. The polar group is not particularly limited, but is preferably a carboxy group, a hydroxy group, an alkoxycarbonyl group, an allyloxycarbonyl group, an amino group, an amide group, or a cyano group. The halogen atom is not particularly limited, but is preferably a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. Among these, R ⁶ is preferably a polar group, a carboxy group, hydroxy group, more preferably an alkoxycarbonyl group or an allyloxycarbonyl group. Further, from the viewpoint of ensuring solubility during solution film formation, an alkoxycarbonyl group or an allyloxycarbonyl group is more preferable.

By using a cycloolefin monomer represented by the general formula (A-2), the molecular symmetry is lowered, and the diffusion motion of the resin at the time of solvent volatilization is easily promoted.

In the general formula (A-2), p represents an integer of 0 to 2.

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

Examples of the copolymerizable monomer copolymerizable with the cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2) include the general formula (A-1) or the general formula (A-2). ) And a ring-open copolymerizable copolymerizable monomer, and an addition copolymerizable copolymer with a cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2). Contains sex monomers.

Examples of the copolymerizable monomer represented by the general formula (A-1) or the general formula (A-2) and the open-ring copolymerizable monomer include cyclobutene, cyclopentene, cycloheptene, cyclooctene, and dicyclopentadiene. Other cycloolefin monomers such as.

Examples of copolymerizable monomers that can be additionally copolymerized with the cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2) include unsaturated double bond-containing compounds and vinyl-based cyclic hydrocarbons. Contains compounds, (meth) acrylates. Examples of unsaturated double bond-containing compounds are olefin compounds having 2 to 12 (preferably 2 to 8) carbon atoms, and examples thereof include ethylene, propylene, and butene. Examples of vinyl-based cyclic hydrocarbon compounds include vinyl cyclopentene-based monomers such as 4-vinylcyclopentene and 2-methyl-4-isopropenylcyclopentene. Examples of (meth) acrylates include alkyl (meth) acrylates having 1 to 20 carbon atoms such as methyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate.

The content of the structural units derived from the cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2) is preferably 50 to 50 with respect to the total of the structural units constituting the cycloolefin resin. It is 100 mol%, more preferably 60 to 100 mol%, still more preferably 70 to 100 mol%.

As the cycloolefin resin, a polymer obtained by homopolymerizing or copolymerizing a cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2) is preferable, and examples thereof include the following. Be done. Among these, (1) to (3) and (5) are preferable, and (3) and (5) are more preferable.

(1) A ring-opening polymer of a cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2);
(2) A ring-opening copolymer of a cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2) and a copolymerizable monomer;
(3) Hydrogenated (co) polymer of the ring-opening (co) polymer of the above (1) or (2);
(4) The ring-opening (co) polymer according to (1) or (2) above was cyclized by a Friedelcraft reaction and then hydrogenated (co) polymer;
(5) A copolymer of a cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2) and an unsaturated double bond-containing compound;
(6) Addition (co) polymer of cycloolefin monomer represented by general formula (A-1) or general formula (A-2) and hydrogenated (co) polymer thereof;
(7) An alternating copolymer of a cycloolefin monomer represented by the general formula (A-1) or the general formula (A-2) and a methacrylate or an acrylate.

Further, examples of the cycloolefin resin include those having at least one of a structural unit represented by the following general formula (B-1) and a structural unit represented by the following general formula (B-2). .. Among these, a polymer containing a structural unit represented by the general formula (B-2), or a polymer containing a structural unit represented by the general formula (B-2), or a polymer containing a structural unit represented by the general formula (B-2), from the viewpoint that a film having a high glass transition temperature and a high permeability of the obtained cycloolefin resin can be easily obtained. A copolymer having a structural unit represented by the general formula (B-1) and a structural unit represented by the general formula (B-2) is preferable.

In the general formula (B-1), X is a group represented by -CH = CH- or a group represented by -CH ₂ CH _2- . R ¹ ~ ^{R 4} and p are each identical to ^R 1 ~ ^{R 4} and p of the general formula (A-1).

In the general formula (B-2), X is a group represented by -CH = CH- or a group represented by -CH ₂ CH _2- . ^R 5, ^{R 6} and p in the general formula (B-2) are respectively identical to ^R 5, ^{R 6} and p in the general formula (A-2).

The intrinsic viscosity [η] _inh of the cycloolefin resin is not particularly limited ^{, but is preferably 0.2 to 5 cm 3} / g, more preferably 0.3 to 3 cm ³ / g, and 0.4 to 0.4 to g. It is more preferably 1.5 cm ^{3 / g.} The intrinsic viscosity [η] _inh of the cycloolefin resin can be measured by JIS K 7637-1: 2002.

The number average molecular weight (Mn) of the cycloolefin resin is not particularly limited, but is preferably 8000 to 100,000, more preferably 10,000 to 80,000, and even more preferably 12,000 to 50,000. The weight average molecular weight (Mw) of the cycloolefin 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 the weight average molecular weight (Mw) can be measured in terms of polystyrene by gel permeation chromatography (GPC).

When the intrinsic viscosity [η] _inh , the number average molecular weight and the weight average molecular weight are in the above ranges, the heat resistance, water resistance, chemical resistance, mechanical properties and molding processability as a film of the cycloolefin resin are better. Become.

The glass transition temperature (Tg) of the cycloolefin resin is not particularly limited, but is preferably 110 ° C. or higher, more preferably 110 to 350 ° C., further preferably 120 to 250 ° C., and 120 to 120 ° C. It is particularly preferable that the temperature is 220 ° C. When Tg is 110 ° C. or higher, deformation is less likely to occur due to secondary processing such as use under high temperature conditions, coating, and printing. On the other hand, when the Tg is 350 ° C. or lower, the molding process becomes easier and the possibility that the resin is deteriorated by the heat during the molding process becomes lower. The Tg of the cycloolefin resin can be measured by JIS K 7121-1987.

As the cycloolefin resin, a commercially available product or a synthetic product may be used. Examples of commercially available products include, but are not limited to, Arton (ARTON) (registered trademark, the same shall apply hereinafter) G (for example, Arton G7810), Arton F, Arton R, Arton RX, etc. manufactured by JSR Corporation. Will be.

The cycloolefin resin can be used alone or in combination of two or more.

In addition, the base material can be used alone or in combination of two or more.

(particle)
The translucent layer A according to the embodiment of the present invention contains particles. The particles act to scatter the light transmitted through the optical film by being dispersed in the translucent layer A. Therefore, when the translucent layer A does not contain particles, it is insufficient to suppress deterioration of the image quality derived from the joint between the panel units in the display device having the display surface composed of the plurality of panel units.

In this specification, the particles do not contain the colorant described later.

The particles are not particularly limited, and examples thereof include organic particles, inorganic particles, and organic-inorganic composite particles.

The organic particles are not particularly limited, and examples thereof include polymethylmethacrylate beads, acrylic-styrene copolymer beads, melamine beads, polycarbonate beads, styrene beads, crosslinked polystyrene beads, polyvinyl chloride beads, benzoguanamine-melamine formaldehyde beads and the like. Can be mentioned.

The inorganic particles are not particularly limited, but are, for example, inorganic oxidation consisting of an oxide containing at least one selected from zirconium, titanium, aluminum, indium, zinc, tin, antimony, cerium, niobium, tungsten, silicon and the like. Examples include object particles. _{_{_{_{Specifically, ZrO 2, ZrSiO 4, TiO}}}} 2, BaTiO 3, SrTiO 3, Al 2 O 3, _{_{zeolites, In 2 O 3, ITO (}} Indium Tin Oxide), ZnO, SnO 2, Sb 2 O 3, CeO ₂ , Nb ₂ O ₅ , WO ₃ , silica (SiO ₂ ) and the like can be mentioned.

Among these, inorganic particles are preferable, inorganic oxide particles are more preferable, oxides containing silicon are further preferable, and silica (SiO ₂ ) is particularly preferable.

Further, the particles may have a multi-layer structure including a core-shell structure.

It is possible to select whether these particles are used with surface treatment or without surface treatment.

When surface treatment is performed, specific materials for surface treatment include dissimilar inorganic oxides such as silicon oxide and zirconium oxide, metal hydroxides such as aluminum hydroxide, and organic acids such as organosiloxane and stearic acid. Be done. As these surface treatment materials, one type may be used alone, or a plurality of types may be used in combination. Among them, from the viewpoint of the stability of the dispersion liquid, at least one of a dissimilar inorganic oxide and a metal hydroxide is preferable as a surface treatment material, and a metal hydroxide is more preferable.

The average secondary particle diameter of the particles is not particularly limited, but is preferably 50 nm or more, more preferably 100 nm or more, and further preferably 150 nm or more. Within these ranges, the effect of suppressing deterioration of image quality derived from the joints between the panel units is further improved. The average secondary particle diameter of the particles is preferably 1000 nm or less, more preferably 500 nm or less, and even more preferably 300 nm or less. Within these ranges, the effect of suppressing deterioration of image quality, which makes the image unclear as a whole, is further enhanced.

The average secondary particle size of the particles can be obtained by directly measuring the size of the secondary particles from the electron micrograph of the layer. Specifically, the particle image was measured by a transmission electron micrograph (TEM) (H-7650 manufactured by Hitachi High-Tech Co., Ltd.), and the average value of the equivalent diameters of 100 secondary particles selected at random. Is obtained, and this value is taken as the average secondary particle diameter.

As the particles, a commercially available product or a synthetic product may be used. The commercially available product is not particularly limited, and examples thereof include R972V manufactured by Nippon Aerosil Co., Ltd.

The particles can be used alone or in combination of two or more.

The content of the particles in the translucent layer A is not particularly limited, but is preferably 0.01 part by mass or more, and more preferably 0.05 part by mass or more with respect to 100 parts by mass of the base material. It is more preferably 0.1 part by mass or more, and particularly preferably 0.3 part by mass or more. Within these ranges, the effect of suppressing deterioration of image quality derived from the joints between the panel units is further improved. The content of the particles in the translucent layer A is not particularly limited, but is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, based on 100 parts by mass of the base material. It is more preferably 1 part by mass or less. Within these ranges, the effect of suppressing deterioration of image quality, which makes the image unclear as a whole, is further enhanced.

(Colorant)
The translucent layer A according to the embodiment of the present invention contains a colorant. The colorant colors the translucent layer A and acts to control the total light transmittance of the optical film. Therefore, when the translucent layer A does not contain a colorant, in a display device having a display surface composed of a plurality of panel units, it is insufficient to suppress deterioration of image quality derived from joints between the panel units. ..

The colorant is not particularly limited, and examples thereof include dyes and pigments.

The pigment is not particularly limited, and examples thereof include organic pigments, inorganic pigments, minerals and the like having the following numbers listed in the color index.

The black pigment is not particularly limited, and examples thereof include carbon black, magnetic materials, and iron / titanium composite oxide black. Here, the carbon black is not particularly limited, and examples thereof include channel black, furnace black, acetylene black, thermal black, and lamp black. The magnetic material is not particularly limited, and examples thereof include ferrite and magnetite.

The red or magenta pigment is not particularly limited, but for example, C.I. I. Pigment 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, Pigment Orange 13, 16, 20, 36, Ruby (chromium-containing corundum), garnet (garnet), spinel (spine) and the like can be mentioned.

The blue or cyan pigment is not particularly limited, but for example, C.I. I. Pigment Blue 1, 15, 15: 1, 15: 2, 15: 3, 15: 4, 15: 6, 16, 17-1, 22, 27, 28, 29, 36, 60, blue sapphire (iron, titanium) Containing corundum) and the like.

The green pigment is not particularly limited, but for example, C.I. I. Pigment Green 7, 26, 36, 50 and the like.

The yellow pigment is not particularly limited, but for example, C.I. I.

Pigment 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, yellow sapphire (nickel-containing corundum) and the like can be mentioned.

The dye is not particularly limited, and examples thereof include conventionally known dyes, for example, those described in paragraphs "0057" to "0060" of International Publication No. 2015/111351.

As the colorant, when the base material is a resin, a pigment is preferable from the viewpoint of having good dispersion stability with respect to the resin and having excellent weather resistance. That is, it is more preferable that the translucent layer A according to the embodiment of the present invention further contains a pigment and a resin in addition to the above particles. Further, among the pigments, a black pigment is more preferable, and a carbon black is further preferable, from the viewpoint that the change in the color of the image is more suppressed and the effect of the present invention is more preferably exhibited.

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, and more preferably 0.2 μm or more. Within these ranges, the slidability becomes better and it becomes more difficult to aggregate, so that the unevenness of the total light transmittance of the film is further reduced. 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 these ranges, dispersion spots in the film are less likely to occur, unevenness in the total light transmittance of the film is further reduced, and the haze value is also lowered.

The average secondary particle size of the pigment can be obtained by directly measuring the size of the secondary particles from the electron micrograph of the layer. Specifically, the particle image was measured by a transmission electron micrograph (TEM) (H-7650 manufactured by Hitachi High-Tech Co., Ltd.), and the average value of the equivalent diameters of 100 secondary particles selected at random. Is obtained, and this value is taken as the average secondary particle diameter.

As the colorant, a commercially available product or a synthetic product may be used. The commercially available product is not particularly limited, and examples thereof include # 950 manufactured by Mitsubishi Chemical Corporation.

The colorant can be used alone or in combination of two or more.

The content of the colorant in the translucent layer A is not particularly limited, but is preferably 0.01 part by mass or more, and preferably 0.05 part by mass or more with respect to 100 parts by mass of the base material. It is more preferably 0.1 part by mass or more, and further preferably 0.1 part by mass or more. Within these ranges, the effect of suppressing deterioration of image quality derived from the joints between the panel units is further improved. The content of the colorant in the translucent layer A is not particularly limited, but is preferably 10 parts by mass or less and more preferably 5 parts by mass or less with respect to 100 parts by mass of the base material. It is more preferably 1 part by mass or less, and particularly preferably 0.6 part by mass or less. Within these ranges, the brightness is further improved.

(Other ingredients)
The translucent layer A according to the embodiment of the present invention may further contain components other than the components described above as long as the effects of the present invention are not impaired. The other components are not particularly limited, and examples thereof include known components used in the field of optical films and known fields of functional layers for optical applications. Specific examples thereof include, but are not limited to, a phase difference adjuster, a wavelength dispersion adjuster, a plasticizer, an ultraviolet absorber, an antioxidant, a hydrogen-bonding solvent, and an ionic surfactant. ..

(Total light transmittance)
The total light transmittance of the translucent layer A according to the embodiment of the present invention is 10% or more and 30% or less. If the total light transmittance is less than 10%, the brightness becomes insufficient in a display device having a display surface composed of a plurality of panel units. Further, when the total light transmittance is more than 30%, the deterioration of the image quality derived from the joint between the panel units in the display device having the display surface composed of the plurality of panel units is insufficiently suppressed. The total light transmittance of the translucent layer A shall be 15% or more and 25% or less from the viewpoint of improving both the brightness and the effect of suppressing the deterioration of the image quality derived from the joint between the multiple panel units. Is preferable.

The total light transmittance can be measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) according to JIS K 7631-1: 1997 (test method for total light transmittance of plastic-transparent material). ..

(Surface modification treatment of translucent layer A)
The translucent layer A may be surface-modified. The method of the surface modification treatment is not particularly limited, and examples thereof include a corona discharge treatment, a flame treatment, an oxidation treatment, and a plasma treatment.

(Film thickness)
The film thickness of the translucent 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 these ranges, the effect of suppressing deterioration of image quality derived from the joints between the panel units in a display device having a display surface composed of a plurality of panel units is further improved. The film thickness of the translucent 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 these ranges, the brightness is further improved in a display device having a display surface composed of a plurality of panel units.

<Optical film containing a translucent layer A and a base material layer>
In one embodiment of the present invention, the translucent layer A may be used as a single-layer film composed of only the layer, or may form a part of an optical film, but is one of the optical films. It is preferable to form a part.

It is preferable that the optical film according to the embodiment of the present invention further includes a base material layer which is another layer. The base material layer can contribute to the protection of the translucent layer A, the impartation of mechanical properties to the optical film, the improvement of the handling suitability of the optical film, and the like. Further, the base material layer may be a release film that is peeled off during use. The base material layer may have a functional layer on one side or both sides, as will be described later.

The base material layer is not particularly limited, but is preferably a translucent layer B. The translucent layer B is not particularly limited as long as it can transmit at least a part of the incident light. The total light transmittance of the translucent layer B is preferably 50% or more, more preferably 60% or more, further preferably 80% or more, and particularly preferably 90% or more. .. Within these ranges, when an optical film including the above-mentioned translucent layer A and another translucent layer B is used, a display surface composed of a plurality of panel units is used. The brightness is further improved in the display device having the above. The total light transmittance of the translucent layer B is not particularly limited, but is more preferably 95% or less, further preferably 93% or less, and particularly preferably 91% or less. Within these ranges, it becomes easier to satisfy the relationship between the haze values of the translucent layer A and the translucent layer B, which will be described later.

In the optical film according to the embodiment of the present invention, the base material layer is a translucent layer B which is another translucent layer, and the translucent layer B is arranged on the translucent layer A. The translucent layer A and the translucent layer B are the translucent layer A when the haze of the laminate of one translucent layer A and one translucent layer B is measured. The value Hz (AB) (%) when light is incident from the side and the value Hz (BA) (%) when light is incident from the translucent layer B side are Hz ( It is preferable to satisfy the relationship of AB) <Hz (BA). By satisfying this relationship, in a display device having a display surface composed of a plurality of panel units, the suppression of deterioration of the image quality derived from the joint between the panel units is further improved. The reason for this is that the light transmitted through the optical film is transmitted by arranging the optical film with the transparent layer A facing the light emitting module side and the transparent layer B facing the display surface side (that is, the visual recognition side in the display device). It is presumed that this is because the light is scattered more, but the correctness does not affect the technical scope of the present invention.

The haze value can be measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) according to JIS K 7136: 2000.

In the present specification, "the translucent layer B is arranged on the translucent layer A" means that the translucent layer A is in contact with the translucent layer A on the surface of the translucent layer A. Not only the structure in which the layer B is arranged, but also the translucent layer B is arranged on the translucent layer A between the translucent layer A and the translucent layer B via another member. It means that the configuration to be used is also included. Among these, it is preferable that the translucent layer B is arranged on the surface of the translucent layer A so as to be in contact with the translucent layer A.

Further, in one embodiment of the present invention, the number of base material layers may be one or two or more, but one is preferable. Regardless of whether the optical film has only one base material layer or two or more base layers, it is preferable that the translucent layer A constitutes one outermost surface of the optical film.

(Base material of base material)
The base material layer (when the base material layer has a functional layer described later, a layer or a film that serves as a base (that is, a base) of the base material layer) preferably contains a base material. In the present specification, when the base material layer such as the translucent layer B described later has the functional layer described later, the layer or film on which the functional layer is formed is referred to as "mother". Or "basic".

The content of the base material is not particularly limited, but from the viewpoint of light transmission, a base material layer (when the base material layer has a functional layer described later, a layer or film serving as a base (base) of the base material layer). Etc.), it is preferably more than 50% by mass, more preferably more than 80% by mass, and further preferably more than 90% by mass with respect to the total mass. Further, the content of the base material is a layer that becomes a base material (base) of the base material layer (when the base material layer has a functional layer described later, the base material layer is a base material) from the viewpoint of light absorption and light scattering property. Alternatively, it is preferably less than 100% by mass with respect to the total mass of the film or the like).

The base material of the base material (when the base material has a functional layer described later, a layer or a film serving as a base (that is, a base) of the base layer) is not particularly limited, and the above-mentioned translucency is not particularly limited. The same as those mentioned as the base material of the layer A can be mentioned. Among these, organic materials are preferable.

Further, the base material layer (when the base material layer has a functional layer described later, a layer or a film serving as a base (that is, a base) of the base material layer) is a resin layer such as a resin film (for example, translucent). Resin layer) is preferable. The resin film represents a film containing a resin as a base material. Examples of the resin as the base material include the same as those mentioned as the resin as the base material of the translucent layer A described above. Among these, from the viewpoint of haze value, polyester resin is preferable, and polyethylene terephthalate is more preferable.

The base material can be used alone or in combination of two or more.

(Other components of the substrate layer)
The base material layer (when the base material layer has a functional layer described later, a layer or a film that serves as a base (base) of the base material layer) is other than the base material described above as long as the effect of the present invention is not impaired. It may further contain other components. The other components are not particularly limited, and examples thereof include particles and colorants described in the above-mentioned translucent layer A. Further, for example, each component used in a known optical film field and a known functional layer field for optical applications can be mentioned. Specific examples thereof include particles, colorants, retardation adjusters, wavelength dispersion adjusters, plasticizers, ultraviolet absorbers, antioxidants, hydrogen-bonding solvents, ionic surfactants, etc., but are limited thereto. It is not something that is done.

(Surface modification treatment of base material layer)
The base material layer may be surface-modified. The method of the surface modification treatment is not particularly limited, and examples thereof include a corona discharge treatment, a flame treatment, an oxidation treatment, and a plasma treatment.

(Functional layer of base material layer)
The base material layer may have a functional layer on one side or both sides of a layer or a film that serves as a base (base) thereof. More specifically, the base material layer is on the translucent layer A side (that is, between the translucent layer A and the layer or film that is the base (base) of the base material layer), or is translucent. It may have a functional layer on the opposite side of the sex layer A.

In the present specification, when the base material layer has a functional layer, it is treated as a base material layer including the functional layer. From this, for example, when the translucent layer B has a functional layer, it is treated as the translucent layer B including the functional layer.

The functional layer of the base material layer is not particularly limited, and examples thereof include functional layers used in optical applications. Specific examples thereof include a release layer, an easy-adhesion layer, an antistatic layer, a hard coat layer, an antireflection layer, an antiglare layer, a barrier layer, a cushioning layer, an easy-slip layer, and the like, but are limited thereto. It's not a thing. Among these, the easy-adhesion layer or the hard coat layer is preferable, and the easy-adhesion layer is more preferable.

The easy-adhesion layer is not particularly limited, and a known easy-adhesion layer can be appropriately used.

In the optical film according to the embodiment of the present invention, it is preferable to provide the easy-adhesion layer only on one surface of the layer or film which is the base (base) of the translucent layer B, or on both surfaces. .. Among these, it is more preferable to provide an easy-adhesion layer on the surface of the translucent layer A side, such as at least a layer or a film that serves as a base (base) of the translucent layer B.

The hard coat layer is not particularly limited, and examples thereof include a cured layer containing a resin containing an alicyclic hydrocarbon and fine particles coated with a polymer silane coupling agent. When the hard coat layer is provided, it is preferable to further provide a cushioning layer between the hard coat layer and the film. The buffer layer is not particularly limited, and examples thereof include a layer containing a resin different from the resin contained in the hard coat layer and fine particles coated with a polymer silane coupling agent.

In the optical film according to the embodiment of the present invention, the hard coat layer is preferably provided on only one surface side such as a layer or film serving as a base (base) of the translucent layer B, or on both surface sides. .. Among these, it is more preferable to provide at least a hard coat layer on the surface side opposite to the translucent layer A, such as a layer or a film that serves as a base (base) of the translucent layer B. Further, it is more preferable to provide the hard coat layer only on the surface side opposite to the translucent layer A, such as a layer or a film that serves as a base (base) of the translucent layer B.

The base material layer may have only one functional layer on one side or both sides, or may have two or more laminated layers.

The film thickness of the functional layer of the base material layer is not particularly limited, but is preferably less than 10 μm, more preferably less than 8 μm, further preferably less than 5 μm, and particularly preferably less than 3 μm. (Lower limit over 0 μm).

(Film thickness of base material layer)
The film thickness of the base material 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 these ranges, the protective effect of the translucent layer A, the effect of imparting mechanical properties to the optical film, the handling suitability of the optical film, and the like are further improved. Further, when the base material layer is the translucent layer B, in a display device having a display surface composed of a plurality of panel units, the suppression of deterioration of image quality derived from the joints between the panel units is further improved. The film thickness of the base material 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 these ranges, when the base material layer is a translucent layer, the brightness is further improved in a display device having a display surface composed of a plurality of panel units.

In one embodiment of the present invention, the film thickness of the translucent layer A is preferably thinner than the film thickness of the base material layer.

(Example of base material layer)
A commercially available product may be used as the base material layer. The commercial product is not particularly limited, but when the base material layer is the translucent layer B, for example, Zeonoa (registered trademark) ZF16 manufactured by Nippon Zeon Corporation and Cosmo Shine (registered trademark) manufactured by Toyobo Corporation. ) A4300 and the like can be mentioned.

<Other functional layers>
The optical film according to the embodiment of the present invention may further have a functional layer other than the translucent layer A and the base material layer, that is, a functional layer other than the above-mentioned functional layer of the base material layer. .. For example, the optical film according to the embodiment of the present invention may further have another functional layer on one side or both sides of the translucent layer A, if necessary. The details of the other functional layers are also the same as the description of the functional layers of the base material layer described above.

When the optical film according to the embodiment of the present invention has another functional layer on one side or both sides of the translucent layer A, the translucent layer A and the translucent layer A are provided on one side or both sides. The total light transmittance of the laminated body with the other functional layer obtained is preferably 10% or more and 30% or less, and more preferably 15% or more and 25% or less. The total light transmittance can be measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) according to JIS K 7631-1: 1997 (test method for total light transmittance of plastic-transparent material). ..

Further, in the optical film according to the embodiment of the present invention, when another functional layer is provided on one side or both sides of the translucent layer A, one translucent layer A and one translucent layer B are used. When the haze of the laminated body with the other functional layers provided on one side or both sides of the translucent layer A is measured, the value Hz (AB) when light is incident from the translucent layer A side. ) (%) And the value Hz (BA) (%) when light is incident from the translucent layer B side have a relationship of Hz (AB) <Hz (BA). It is preferable to meet. The haze value can be measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) according to JIS K 7136: 2000.

<Film configuration example>
1 (A) to 1 (C) each show a structural example of a film used in one embodiment of the present invention. FIG. 1A represents a single-layer film composed of only the translucent layer A1. Further, FIG. 1B represents a laminated film 2 in which a translucent layer A 1 and a translucent layer B 3 are laminated. In FIG. 1B, one outermost surface is formed by the translucent layer A1 and the other outermost surface is formed by the translucent layer B3. The translucent layer B 3 is arranged so as to be in contact with the translucent layer A 1. For example, the translucent layer B has an easily adhesive layer (not shown), and the easily adhesive layer (not shown) is in contact with the translucent layer A1 on the surface of the translucent layer A1. It is also preferable that the translucent layer B 3 having the above is arranged. Further, FIG. 1C shows a laminated film 2 in which a translucent layer A 1 and a translucent layer B 3 are laminated, and further, the translucent layer B 3 is a translucent layer A. Represents a film having a hard coat layer 4 constituting a surface opposite to the one side. In FIG. (1) C, one outermost surface is composed of the translucent layer A1, and the translucent layer B 3 is in contact with the translucent layer A 1 on the surface of the translucent layer A 1. Is placed. For example, the translucent layer B has an easily adhesive layer (not shown), and the easily adhesive layer (not shown) is in contact with the translucent layer A1 on the surface of the translucent layer A1. It is also preferable that the translucent layer B 3 having the above is arranged. Further, for example, it is also preferable that the hard coat layer 4 is formed on the easy-adhesion layer (not shown) of the translucent layer B3 having the easy-adhesion layer (not shown). In addition, in FIG. 1C, 3'represents the layer or film which becomes the base (base) of the translucent layer B3.

<Film manufacturing method>
The method for producing an optical film according to an embodiment of the present invention is not particularly limited, and a known method for producing an optical film can be used. For example, a coating method, a solution casting method, a melt casting method, a gas phase film forming method and the like can be mentioned. Among these, 1) a coating liquid preparation step for obtaining a coating liquid for forming a translucent layer A, and 2) a coating film for applying the obtained coating liquid for forming a translucent layer A to the surface of a support. A method having a forming step and a drying step of 3) removing the solvent from the coating film of the applied coating liquid for forming the translucent layer A to form the translucent layer A is preferable.

Here, when the support is a base material layer (for example, a translucent layer B), a laminated film including the translucent layer A and the base material layer can be produced by the production method. can.

1) Coating liquid preparation step In this step, the coating liquid for forming the translucent layer A containing the particles described in the translucent layer A above, the colorant described in the translucent layer A above, and the solvent. To prepare. The coating liquid for forming the translucent layer A may further contain a base material (for example, a resin) or other components, if necessary.

As the coating liquid for forming the translucent layer A, a particle dispersion liquid and a colorant dispersion liquid or a colorant solution are prepared, and these dispersion liquids or solutions, a solvent, and if necessary, a base material are used. It is preferable to prepare by mixing with other components as needed. The preparation of the particle dispersion liquid and the colorant dispersion liquid or the colorant solution are not particularly limited, but it is preferable to use those listed as examples of the solvent used in the following coating liquid for forming the translucent layer A. .. Further, in the preparation of the particle dispersion liquid and the colorant dispersion liquid or the colorant solution, it is preferable to perform filtration. A known filtration device can be appropriately used for filtration.

The solvent used for the coating liquid for forming the translucent layer A is not particularly limited, but for example, chlorine-based solvents such as chloroform and dichloromethane, methanol, ethanol, propanol, n-butanol, 2-butanol, tert-butanol, and cyclo Alcohols such as hexanol, 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, glycol ethers (propylene glycol mono (C1 ~) C4) Alkyl ether (specifically, propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, propylene glycol mono-n-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, n-hexane and the like can be mentioned. Among these, from the viewpoint of easily dissolving the base material, having a low boiling point, and easily increasing the drying rate and productivity, it is preferable to contain a chlorine-based solvent, alcohols, and ketones, and it is preferable to contain a chlorine-based solvent. More preferred.

Further, from the viewpoint that it is easy to form the translucent layer A having high flatness, it is preferable to contain a chlorine-based solvent, alcohols, and ketones. Dichloromethane is preferable as the chlorine-based solvent. As the alcohols, methanol or ethanol is preferable, and ethanol is more preferable. As the ketones, methyl ethyl ketone or acetone is preferable, and methyl ethyl ketone is more preferable. That is, it is particularly preferable to contain dichloromethane and at least one of ethanol and methyl ethyl ketone.

When the solvent contains a chlorine-based solvent and another solvent, the content ratio of the chlorine-based solvent is not particularly limited, but from the viewpoint of achieving both drying speed and flatness, the chlorine-based solvent / other solvent = less than 100. It is preferably more than / 0 to 60/40 (mass ratio), more preferably 99.9 / 0.1 to 90/10 (mass ratio), and 99.5 / 0.5 to 99/1. (Mass ratio) is more preferable. When the ratio of the chlorine-based solvent is moderately high, it is easy to improve the drying property and productivity.

The concentration of the base material in the coating liquid for forming the translucent layer A is preferably 1 to 20% by mass from the viewpoint of making it easy to adjust the viscosity within an appropriate range. Further, from the viewpoint of reducing the amount of shrinkage of the coating film during drying, the concentration of the base material in the coating liquid for forming the translucent layer A is more preferably more than 5% by mass and 20% by mass or less. It is more preferably more than mass% and 15% by mass or less.

The mixing conditions are not particularly limited in the preparation of various dispersions or solutions such as the coating liquid for forming the translucent layer A, the preparation of the particle dispersion, the colorant dispersion or the colorant solution. As the mixing temperature, it may be mixed at room temperature, or it may be mixed while heating in order to improve the solubility. The mixing time is not particularly limited, but when the base material is mixed, it is preferably a time during which the base material is completely dissolved. In addition, a known mixing device can be appropriately used for mixing.

The viscosity of the coating liquid for forming the translucent layer A is not particularly limited, but is preferably 5 to 5000 mPa · s. When the viscosity of the coating liquid for forming the translucent layer A is 5 mPa · s or more, it becomes easier to form a layer having an appropriate thickness. Further, when the viscosity of the coating liquid for forming the translucent layer A is 5000 mPa · s or less, the occurrence of thickness unevenness can be further suppressed due to the increase in the viscosity of the solution. From the same viewpoint, the viscosity of the coating liquid for forming the translucent layer A is more preferably 100 to 1000 mPa · s. The viscosity can be measured with an E-type viscometer at 25 ° C.

2) Coating film forming step In this step, the obtained coating liquid for forming the translucent layer A is applied to the surface of the support. Specifically, the obtained coating liquid for forming the translucent layer A is applied to the surface of the support.

The coating method of the coating liquid for forming the translucent layer A is not particularly limited, and a known coating method can be used. For example, a back coat method, a gravure coat method, a spin coat method, a wire bar coat method, a roll coat method and the like can be mentioned. Among these, the back coat method is preferable from the viewpoint of being able to form a thin and uniform thickness coating film.

When manufacturing a laminated film, it is preferable to use a base material layer as a support as described above. The details of the base material layer are as described above. When a base material layer is used as the support, the base material layer has a functional layer (for example, an easily adhesive layer), and is used for forming the translucent layer A on the surface on which the functional layer is formed. It is also preferable to apply a coating liquid.

3) Drying step In this step, the solvent is removed from the coating film of the coating liquid for forming the translucent layer A applied to the support to form the translucent layer A. Specifically, the coating film of the coating liquid for forming the translucent layer A applied to the support is dried.

The method of applying the coating liquid for forming the translucent layer A is not particularly limited, and a known drying method can be used. For example, a method by blowing air or heating can be mentioned. Among these, the method by blowing air is preferable from the viewpoint of facilitating the suppression of curl and the like.

The drying speed of the coating film is not particularly limited, ^{but is preferably 0.0015 to 0.05 kg / hr · m 2} , and more preferably 0.002 to 0.05 kg / hr · m ² . The drying rate is expressed as the mass of the solvent that evaporates per unit time and unit area. The drying rate can usually be adjusted by the drying temperature. The drying temperature is not particularly limited, but is preferably (Tb-50) to (Tb + 50) ° C., for example, 50 to 200 ° C. with respect to the boiling point Tb of the solvent used.

For example, by peeling the translucent layer A from the support after this step, a single-layer film composed of only the translucent layer A can be obtained.

Further, for example, when a base material layer is used as a support, after this step, as a result of forming the base material layer, a laminated film including the translucent layer A and the base material layer is formed. .. In this case, the translucent layer A can be used as it is as a laminated film without peeling from the base material layer. In particular, the base material layer is a translucent layer B composed of only the above-mentioned base layer or film, or a translucent layer B having a functional layer (for example, an easily adhesive layer). In this case, the translucent layer A can be used as it is as an optical film without being peeled off.

4) Winding step The optical film according to the embodiment of the present invention may be strip-shaped. Therefore, the method for manufacturing an optical film may further include 4) a winding step of winding a strip-shaped optical film into a roll to form a roll.

In this step, the width of the obtained strip-shaped translucent layer A, a laminate of the translucent layer A and the base material layer, or a layer obtained by forming another functional layer on these, if necessary, is used. It is wound into a roll in a direction orthogonal to the direction to form a roll body.

The length of the strip-shaped optical film is not particularly limited, but is preferably about 100 to 10,000 m, for example. The width of the strip-shaped optical film is preferably 1 m or more, more preferably 1.3 to 4 m.

<Film manufacturing equipment>
The optical film according to the embodiment of the present invention is not particularly limited, but can be manufactured by, for example, the manufacturing apparatus shown in FIG.

FIG. 2 is a schematic view of a manufacturing apparatus 200 for manufacturing an optical film according to an embodiment of the present invention. The manufacturing apparatus 200 includes a supply unit 210, a coating unit 220, a drying unit 230, a cooling unit 240, and a winding unit 250. Reference numerals a to d indicate transport rolls for transporting the support 110.

The supply unit 210 has a feeding device (not shown) for feeding out the roll body 201 of the strip-shaped support 110 wound around the winding core.

The coating unit 220 is a coating device, and includes a backup roll 221 that holds the support 110 and a coating head 222 that applies the coating liquid for forming the translucent layer A to the support 110 held by the backup roll 221. It has a decompression chamber 223 provided on the upstream side of the coating head 222.

The flow rate of the coating liquid for forming the translucent 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 translucent layer A discharged from the coating head 222 is set to an amount capable of stably forming a coating layer having a predetermined film thickness when continuously coated under the conditions of the coating head 222 adjusted in advance. Has been done.

The decompression chamber 223 is a mechanism for stabilizing a bead (pool of coating liquid) formed between the coating liquid for forming the translucent layer A from the coating head 222 and the support 110 at the time of coating, and the pressure reducing chamber 223 is depressurized. The degree can be adjusted. The decompression chamber 223 is connected to a decompression blower (not shown) so that the inside is decompressed. The decompression chamber 223 is in a state where there is no air leakage, and the gap with the backup roll is narrowly adjusted so that a stable bead of the coating liquid can be formed.

The drying unit 230 is a drying device that dries the coating film applied to the surface of the support 110, and has a drying chamber 231, a drying gas introduction port 232, and a discharge port 233. The temperature and air volume of the dry air are appropriately determined depending on the type of the coating film and the type of the support 110. By setting conditions such as the temperature and air volume of the drying air and the drying time in the drying unit 230, the amount of residual solvent in the coating film after drying can be adjusted. The amount of residual solvent in the coating film after drying can be measured by comparing the unit mass of the coating film after drying with the mass after the coating film is sufficiently dried.

The cooling unit 240 cools the temperature of the support 110 having the coating film (translucent layer A (not shown)) obtained by drying in the drying unit 230, and adjusts the temperature to an appropriate temperature. The cooling unit 240 has a cooling chamber 241, a cooling air inlet 242, and a cooling air outlet 243. The temperature and air volume of the cooling air can be appropriately determined depending on the type of the coating film and the type of the support 110. Further, even if the cooling unit 240 is not provided, the cooling unit 240 may not be provided if the cooling temperature is appropriate.

The winding unit 250 is a winding device (not shown) for winding the support 110 (laminated body 100) on which the translucent layer A (not shown) is formed to obtain the roll body 251.

When producing a laminated film, it is preferable to use a base material layer (for example, a translucent layer B) as the support 110 as described above. In this case, the laminated body 100 of the translucent layer A and the support becomes a laminated film.

<Use>
The optical film according to an embodiment of the present invention is used for a display device having a display surface composed of a plurality of panel units. The optical film according to the embodiment of the present invention is not particularly limited, but can be preferably applied to, for example, those listed in the following detailed description of the panel unit and the display device.

(Panel unit and display device)
The panel unit to which the above optical film is applied and the display device including the panel unit are not particularly limited, but are preferably a self-luminous panel unit and a display device having a display surface composed of the self-luminous panel unit.

In one embodiment of the present invention, it is more preferable that the above optical film is used for a display device having a display surface composed of a panel unit having a light emitting module. That is, another aspect of the present invention is a plurality of panel units having a light emitting module and the above-mentioned optical film arranged on the display surface side (that is, the visual recognition side in the display device) with respect to the light emitting module. It can also be said that it relates to a panel unit used in a display device having a configured display surface.

Further, in one embodiment of the present invention, when the above-mentioned optical film includes the above-mentioned translucent layer A and the above-mentioned base material layer (preferably, the above-mentioned translucent layer B), the above-mentioned translucent layer A is used. The above-mentioned base material layer (preferably, the translucent layer B) is arranged on the display surface side, and the above-mentioned optical film is used for a display device having a display surface composed of a panel unit having a light emitting module. Is more preferable. That is, another aspect of the present invention has a light emitting module and the above-mentioned optical film arranged on the display surface side of the light-emitting module, and is closer to the display surface side than the above-mentioned translucent layer A. It can also be said that the present invention relates to a panel unit used in a display device having a display surface composed of a plurality of panel units on which the above-mentioned base material layer (preferably a translucent layer B) is arranged. At this time, it is preferable that the translucent layer A constitutes one outermost surface of the optical film, and the surface of the optical film on the translucent layer A side and the light emitting module are arranged so as to face each other.

In one embodiment of the present invention, the panel unit is not particularly limited, and for example, a panel unit having a known light emitting module can be used. Among these, by mounting a small and large number of light emitting elements in a matrix on a wiring board and selectively emitting light from each light emitting element by a light emitting control means connected to the light emitting element, visual information can be obtained from each light emitting element. It is preferable that the light emitting module can be displayed directly on the display screen by blinking. Further, the light emitting element included in the light emitting module is more preferably an LED element. That is, it is more preferable that the light emitting module is an LED module in which the light emitting element is an LED element.

When the panel unit includes the light emitting module and the above optical film, it is preferable that the light emitting module and the above optical film are bonded to each other with an adhesive. When the laminated film is bonded, it is preferable that the base material layer (preferably the translucent layer B) is arranged on the display surface side of the translucent layer A. Then, the light emitting module and the outermost surface on the translucent layer A side of the base layer (preferably the translucent layer B) of the laminated film are bonded to each other with an adhesive. Is preferable. At this time, it is preferable that the translucent layer A constitutes one outermost surface of the optical film, and the surface of the optical film on the translucent layer A side and the light emitting module are bonded so as to face each other. As the adhesive, a known adhesive can be used without particular limitation, and examples thereof include a pressure-sensitive adhesive, a heat-curable adhesive, and a photocurable adhesive. Among these, a pressure-sensitive adhesive is preferable. The pressure-sensitive adhesive is not particularly limited, and is, for example, an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, a silicone-based pressure-sensitive adhesive, a urethane-based pressure-sensitive adhesive, a polyacrylamide-based pressure-sensitive adhesive, or the like. Can be mentioned. In these cases, the panel unit will have a light emitting module, the above optical film, and an adhesive layer arranged between them.

When the panel unit includes the light emitting module and the above optical film, the light emitting module, the above optical film, and other members adopted as necessary are integrated by heat pressing. It may be pasted together. When the laminated film is bonded, the base material layer (preferably the translucent layer B) is arranged on the display surface side of the translucent layer A, and the light emitting module and the laminated film are described above. It is preferable that the outermost surface on the translucent layer A side is bonded to the base material layer (preferably the translucent layer B). At this time, it is preferable that the translucent layer A constitutes one outermost surface of the optical film, and the surface of the optical film on the translucent layer A side and the light emitting module are bonded so as to face each other. The above adhesive may be applied between any members when they are bonded together by hot pressing.

Hereinafter, an example of the configuration of the LED module, which is a kind of the light emitting module, is shown, but the LED module that can be used in the present invention is not limited to this configuration.

The LED module is configured by mounting one or more LED elements on a wiring board in which a wiring portion is formed on a support board. Here, it is preferable that the LED module is configured by mounting a plurality of LED elements.

The wiring board is a circuit board in which a wiring portion formed of, for example, a metal such as copper or another conductive member is formed on the surface of the support board in a form capable of conducting continuity with the LED element. The material of the support substrate is not particularly limited, and examples thereof include conventionally known materials used as substrates for electronic circuits, such as glass epoxy.

In the LED module, the LED element is mounted on the wiring portion via the solder layer in a conductive manner.

The light emission of each LED element is individually controlled by a light emission control means such as an IC chip substrate that is separately bonded.

The size of the LED module is not particularly limited, but in general, from the viewpoint of cost performance, the diagonal length is preferably about 10 inches to 200 inches, and more preferably about 50 inches to 200 inches. ..

The LED element mounted on the wiring board is not particularly limited, but is preferably a light emitting element that utilizes light emission at the PN junction where the P-type semiconductor and the N-type semiconductor are bonded. The structure of such a light emitting element is not particularly limited, but for example, a structure in which P-type electrodes and N-type electrodes are provided on the upper and lower surfaces of the element, and both P-type and N-type electrodes are provided on one surface of the element. The structure can be mentioned. In particular, a minute-sized LED element such as the LED element disclosed as a "chip-shaped electronic component" in Japanese Patent Application Laid-Open No. 2006-339551 is preferably used. The LED element disclosed in the same document is said to have a size of width × depth × height of approximately 25 μm × 15 μm × 2.5 μm.

The LED element preferably includes an LED light emitting chip and a cover that covers the LED element. The material of the resin cover is not particularly limited, and examples thereof include organic insulating materials such as epoxy resin, silicone resin, and polyimide resin. Among these, the LED element protects the LED light emitting chip from physical impact and suppresses the total reflection of light into the semiconductor due to the difference in refractive index between the semiconductor constituting the LED light emitting chip and air. An epoxy resin is preferable from the viewpoint of increasing the luminous efficiency.

It is more preferable that the LED element is a "small size LED element". In the present specification, the "small size LED element" specifically refers to the width (W) and the depth (D) with respect to the size of the entire light emitting element including the LED light emitting chip and the resin cover covering the LED light emitting chip. ) Represents an LED element having a height (H) of 200 μm or less and 300 μm or less. Further, it is more preferable that the width and the depth of the "small size LED element" are both 50 μm or less and the height is 10 μm or less. Further, the arrangement interval of the LED elements is preferably 0.03 mm or more and 100 mm or less, and more preferably 0.05 mm or more and 5 mm or less. A light emitting module (LED module) in which the light emitting element is an LED element has a width and a depth of 50 μm or less, and a minute-sized LED element having a height of 10 μm or less is about several μm to several tens of μm. It is particularly preferable that the LEDs are arranged in a matrix with a pitch of several thousand × several thousand or more. In the present specification, the above-mentioned "small size LED element" has a display surface composed of a panel unit including LED modules arranged in a matrix at an arrangement interval of 0.03 mm or more and 100 mm or less. The display device is referred to as a "micro LED display device".

FIG. 3 is a schematic view showing a cross-sectional structure of a panel unit according to an embodiment of the present invention. The upper part of FIG. 3 is the display surface side (that is, the visual recognition side in the display device). The panel unit 10 has an LED module 11 and a laminated film 2 having a hard coat layer 4. The laminated film 2 is arranged on the display surface side of the light emitting module 11, and the translucent layer B3 is arranged on the display surface side of the translucent layer A1. At this time, the LED module 11 and the surface of the laminated film 2 on the translucent layer A1 side are bonded to each other via the adhesive layer 12. In FIG. 3, 3'represents a layer or film that serves as a base (base) of the translucent layer B3.

The display device represents a display device for visual information such as characters, images, and moving images. The display device to which the above optical film is applied is not particularly limited, and a known device can be used. For example, a non-light emitting device such as a liquid crystal display device, an LED display device, or an organic EL display can be used. Examples thereof include self-luminous devices such as devices. Among these, a self-luminous device is preferable, an LED display device is more preferable, and a micro LED display device as mentioned above is preferable.

It is preferable that each panel unit having a light emitting module is used for a display device having a display surface composed of a plurality of panel units. That is, another aspect of the present invention can be said to relate to a display device having a display surface composed of a plurality of panel units including the above optical film.

In this specification, a display device having a display surface composed of a plurality of panel units is also referred to as an independent module type display device. In the independent module type display device, the plurality of panel units may be laid out in a curved surface shape or may be laid out in a tile shape (matrix shape, flat shape). Among these, it is preferable to spread them in a tile shape. Further, in the plurality of panel units, the individual display surfaces may form independent visual information, or the individual display surfaces may form one visual information as a whole. Among these, it is preferable that each display surface constitutes one visual information as a whole.

FIG. 4 is a schematic view showing a planar structure of an independent module type display device according to an embodiment of the present invention. The display surface of the independent module type display device 20 has a display surface in which a plurality of panel units 10 are laid out in a tile shape (planar shape). Further, it is preferable that the display device having a display surface composed of a plurality of panel units can be disassembled into a display device having a display surface composed of one or a plurality of panel units included therein.

As the light emitting module and display device, for example, known modules and devices described in JP-A-2019-204905 can also be used.

The effects of the present invention will be described with reference to the following examples and comparative examples. However, the technical scope of the present invention is not limited to the following examples.

<Manufacturing of film>
[Film 1 (laminated film)]
(Preparation of particle dispersion)
10 parts by mass of silica particles (R972V manufactured by Nippon Aerosil Co., Ltd.) and 90 parts by mass of ethanol are stirred and mixed with a dissolver for 30 minutes, and then dispersed using a high-pressure disperser, Manton Gorlin, to prepare a dispersion. did. 65 parts by mass of dichloromethane was added to the obtained dispersion with stirring, and the mixture was stirred and mixed with a dissolver for 30 minutes to dilute the mixture. The obtained solution was filtered through a polypropylene wind cartridge filter TCW-PPS-1N manufactured by Advantech Toyo Co., Ltd. to obtain a particle dispersion.

(Preparation of pigment dispersion)
10 parts by mass of carbon black (CB) (# 950 manufactured by Mitsubishi Chemical Corporation) and 90 parts by mass of methyl ethyl ketone (MEK) were stirred and mixed with a dissolver for 30 minutes, and then dispersed for 30 minutes using an ultrasonic disperser. To prepare a dispersion. The obtained dispersion was filtered through a polypropylene wind cartridge filter TCW-PPS-1N manufactured by Advantech Toyo Co., Ltd. to obtain a pigment dispersion.

(Preparation of coating liquid for forming translucent layer A)
First, dichloromethane was added to the pressurized dissolution tank. Next, a cycloolefin resin (COP, a cycloolefin resin having a weight average molecular weight of 140,000 and a polar group (carboxy group), ARTON (registered trademark) G7810 manufactured by JSR Corporation) was added while stirring. Next, the prepared particle dispersion and pigment dispersion are added, heated to 60 ° C. and stirred for 30 minutes to completely dissolve the cycloolefin resin, and the coating liquid for forming the translucent layer A is prepared. Obtained.

<< Composition of coating liquid for forming translucent layer A >>
Cycloolefin resin 100 parts by mass Dichloromethane 890 parts by mass Particle dispersion 5 parts by mass Pigment dispersion 6 parts by mass.

(Preparation of laminated film including translucent layer A and translucent layer B)
As the translucent layer B, Zeonoa (registered trademark) ZF16 (thickness 100 μm manufactured by Nippon Zeon Corporation) was prepared. The above-mentioned coating liquid for forming the translucent layer A was applied onto the translucent layer B by a back coating method using a die. After that, the drying speed is 0.002 kg / hr · m ² , and the temperature of the hot air applied from the translucent layer B side and the temperature of the hot air applied from the coating film side of the coating liquid for forming the translucent layer A are 130 ° C. Then, a translucent layer A having a thickness of 10 μm was formed, and a film 1 as a laminated film was obtained. The average secondary particle size of the silica particles in the translucent layer A was 200 nm, and the average secondary particle size of the pigment was 300 nm.

[Film 2 (laminated film)]
A film that is a laminated film in the same manner except that the translucent layer B is changed to a polyethylene terephthalate film (PET film) (Cosmo Shine (registered trademark) A4300 manufactured by Toyobo Co., Ltd., thickness 50 μm) in the production of the film 1. I got 2.

[Film 3 (laminated film)]
In the production of the film 1, the same applies except that the amount of the pigment dispersion liquid added is changed so that the amount of carbon black added to the translucent layer A is 0.55 part by mass with respect to 100 parts by mass of the cycloolefin resin. A film 3 which is a laminated film was obtained.

[Film 4 (laminated film)]
In the production of the film 1, the amount of the pigment dispersion added was changed so that the amount of carbon black added to the translucent layer A was 0.55 parts by mass with respect to 100 parts by mass of the cycloolefin resin, and the translucency was changed. A laminated film film 4 was obtained in the same manner except that the layer B was changed to a polyethylene terephthalate film (PET film) (Cosmoshine (registered trademark) A4300 manufactured by Toyo Spinning Co., Ltd., thickness 50 μm).

[Film 5 (laminated film)]
In the production of the film 1, the amount of the pigment dispersion added was changed so that the amount of carbon black added to the translucent layer A was 0.50 part by mass with respect to 100 parts by mass of the cycloolefin resin, and the translucency was changed. A laminated film film 5 was obtained in the same manner except that the layer B was changed to a polyethylene terephthalate film (PET film) (Cosmoshine (registered trademark) A4300 manufactured by Toyo Spinning Co., Ltd., thickness 50 μm).

[Film 6 (laminated film)]
In the production of the film 1, the same applies except that the amount of the pigment dispersion liquid added is changed so that the amount of carbon black added to the translucent layer A is 0.50 part by mass with respect to 100 parts by mass of the cycloolefin resin. A film 6 which is a laminated film was obtained.

[Film 7 (single layer film)]
In the production of the film 1, the same applies except that the amount of the pigment dispersion liquid added is changed so that the amount of carbon black added to the translucent layer A is 0.55 parts by mass with respect to 100 parts by mass of the cycloolefin resin. A laminated film containing the translucent layer A and the translucent layer B was obtained. Next, the translucent layer B was peeled off from the obtained laminated film to form only the translucent layer A, whereby a film 7 as a single-layer film was obtained.

[Film 8 (laminated film)]
In the production of the film 1, the particle dispersion was not added during the production of the translucent layer A, and the amount of carbon black added to the translucent layer A was 0.55 parts by mass with respect to 100 parts by mass of the cycloolefin resin. The same applies except that the amount of the pigment dispersion added was changed and the translucent layer B was changed to a polyethylene terephthalate film (PET film) (Cosmo Shine (registered trademark) A4300 manufactured by Toyo Spinning Co., Ltd., thickness 50 μm). A film 8 which is a laminated film was obtained.

[Film 9 (single layer film)]
In the production of the film 1, the particle dispersion was not added during the production of the translucent layer A, and the amount of carbon black added to the translucent layer A was 0.55 parts by mass with respect to 100 parts by mass of the cycloolefin resin. A laminated film containing the translucent layer A and the translucent layer B was obtained in the same manner except that the amount of the pigment dispersion liquid added was changed. Next, the translucent layer B was peeled off from the obtained laminated film to form only the translucent layer A, whereby a film 9 as a single-layer film was obtained.

[Film 10 (laminated film)]
In the production of the film 1, the same applies except that the amount of the pigment dispersion liquid added is changed so that the amount of carbon black added to the translucent layer A is 0.65 parts by mass with respect to 100 parts by mass of the cycloolefin resin. A film 10 which is a laminated film was obtained.

[Film 11 (laminated film)]
In the production of the film 1, the film 11 as a laminated film was obtained in the same manner except that the pigment dispersion was not added during the production of the translucent layer A.

In the films 2 to 11, the thickness of the translucent layer A was 10 μm. Further, in the films 2 to 11, the average secondary particle diameter of the silica particles in the translucent layer A was 200 nm, except for the films 8 and 9 containing no silica particles. In the films 2 to 11, the average secondary particle diameters of the pigments were all 300 nm, except for the films 11 containing no pigment.

The features of each film are shown in Table 1 below.

<Evaluation of film>
[Total light transmittance of translucent layer A and translucent layer B]
With respect to the laminated films 1 to 6, 8, 10 and 11, the translucent layer B is peeled off, and the translucent layer A is left alone, while the single-layer films 7 and 9 remain as they are. The total light transmittance (%) was evaluated in the state (that is, in the state of only the translucent layer A). These results are shown in Table 1 below.

In addition, the total light transmittance of Zeonoa (registered trademark) ZF16 manufactured by Nippon Zeon Corporation and Cosmo Shine (registered trademark) A4300 manufactured by Toyobo Co., Ltd., which were used as the translucent layer B, was measured by the same method. However, it was 91.90% and 90.41%, respectively.

The total light transmittance was measured using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.) according to JIS K 7631-1: 1997 (test method for total light transmittance of plastic-transparent material).

[Haze of laminated film]
For films 1 to 6, 8, 10 and 11 which are laminated films, the haze value Hz (AB) (%) measured from the translucent layer A side and the haze value Hz measured from the translucent layer B side. (BA) (%) was evaluated. The haze value was measured according to JIS K 7136: 2000 using a haze meter (NDH4000, manufactured by Nippon Denshoku Kogyo Co., Ltd.). Table 1 below shows which of Hz (AB) (%) and Hz (BA) (%) has a larger value.

<Evaluation of display device>
[Manufacturing of panel units and display devices]
An adhesive layer made of a pressure-sensitive adhesive is bonded onto the surface of an LED module containing an LED element having a pitch of 2 mm in length and width and having an outer shape of 40 cm in length and 40 cm in width, including a resin cover of the LED element. did. Next, the obtained film was bonded onto the surface of the LED element of the LED module via the adhesive layer to obtain a panel unit. Here, when the film is a laminated film, the film is bonded so that the translucent layer A side of the laminated film and the above-mentioned surface of the LED element face each other. Then, two of the obtained panel units were connected side by side to obtain an independent module type display device.

[Display device brightness and seamlessness]
^{The brightness (cd / m 2} ) of the obtained independent module type display device was measured using Prometric Color 1600 manufactured by Cybernet Systems Co., Ltd., and the brightness average value and brightness uniformity of the panel unit were evaluated. rice field. Here, the value of the luminance uniformity becomes smaller as the seamlessness between the panels increases. From this, the luminance uniformity can be an index of the effect of suppressing the deterioration of the image quality derived from the joint between the panel units in the display device having the display surface composed of a plurality of panel units. The brightness average value and the brightness uniformity can be calculated using the following equations, respectively. In the following formula, the average uniformity is represented by Lu and the average brightness is represented by La.

The average brightness of the independent module type display manufactured in the same manner as above was 3000 cd / m ² , except that the panel unit to which the obtained film was not bonded was used.

L1: The average value of the two panel units with respect to the average value of the brightness of the three points, the center in each panel unit and the point 10 cm above and below the center.
L2: The average value of the brightness of three points, the center between two adjacent panel units and the point 10 cm above and below the center.

Regarding the brightness, it was judged that the evaluations A to C show good results. These results are shown in Table 1 below.

(Brightness evaluation standard)
A: Brightness average value is 1000 (cd / m ² ) or more,
B: The average brightness value is 500 (cd / m ² ) or more and less than 1000 (cd / m ² ),
C: Brightness average value is 200 (cd / m ² ) or more and less than 500 (cd / m ² ),
D: The average luminance value is less than ^{200 (cd / m 2).}

Regarding seamlessness, it was judged that evaluations A to C show good results. These results are shown in Table 1 below.

(Evaluation criteria for seamlessness)
A: Brightness uniformity is 6 or less,
B: Luminance uniformity is more than 6 and 12 or less,
C: Luminance uniformity is more than 12 and 18 or less,
D: Luminance uniformity is over 18.

From Table 1 above, it was confirmed that the display device using the films 1 to 7 according to the present invention is excellent in both seamlessness and brightness. On the other hand, it was confirmed that the films 8 and 9 in which the translucent layer A does not contain particles according to the comparative example are inferior in seamlessness. Further, it was confirmed that the display device using the

films

10 and 11 in which the total light transmittance of the translucent layer A is outside the range of the present invention is insufficient in either seamlessness or brightness.

Further, from the comparison of

films

1, 3 and 6 and the comparison of

films

2, 4 and 5, when the total light transmittance is in the range of 15 to 25%, the balance between seamlessness and brightness becomes better. Was confirmed.

Then, from the comparison of the

films

3, 4 and 7, it was confirmed that the seamlessness is further improved by satisfying the relationship that the laminated film has Hz (AB) <Hz (BA). Further, from the comparison of the

films

1 and 2 and the comparison of the films 6 and 5, it is possible to further improve the seamlessness by satisfying the relationship that the laminated film has Hz (AB) <Hz (BA). confirmed.

This application is based on Japanese Patent Application No. 2020-117339 filed on July 7, 2020, the disclosure of which is incorporated as a whole by reference.

1 Translucent layer A
2 Laminated film 3 Translucent layer B
3'The base layer or film of the translucent layer B 4 Hard coat layer 10 Panel unit 11 LED module 12 Adhesive layer 20 Independent modular display device 100 Laminated body (laminated film)
110 Support (for example, a base material layer such as a translucent layer B)
200 Manufacturing equipment 201 Roll body of support (for example, base material layer such as translucent layer B) 210 Supply part 220 Coating part 221 Backup roll 222 Coating head 223 Decompression chamber 230 Drying portion 231 Drying chamber 232 Introducing drying gas Port 233 Discharge port 240 Cooling part 241 Cooling room 242 Cooling air inlet 243 Cooling air outlet 250 Winding part 251 Roll body of laminated body (laminated film) a, b, c, d Conveying roll.

Claims

A translucent layer containing particles and a colorant and having a total light transmittance of 10% or more and 30% or less.
An optical film used in a display device having a display surface composed of a plurality of panel units.
The optical film according to claim 1, wherein the translucent layer is a resin film.
The optical film according to claim 1 or 2, wherein the total light transmittance of the translucent layer is 15% or more and 25% or less.
The optical film according to any one of claims 1 to 3, wherein the particles are inorganic oxide particles.
The optical film according to any one of claims 1 to 4, wherein the colorant is a pigment.
The translucent layer is a translucent layer A.
Further including a substrate layer,
The optical film according to any one of claims 1 to 5.
The optical film according to claim 6, wherein the base material layer is a resin film.
The base material layer is a translucent layer B, and is
The translucent layer B is arranged on the translucent layer A.
The translucent layer A and the translucent layer B are the translucent layer when the haze of the laminate of one translucent layer A and one translucent layer B is measured. The value Hz (AB) (%) when light is incident from the A side and the value Hz (BA) (%) when light is incident from the translucent layer B side are Satisfy the relationship of Hz (AB) <Hz (BA),
The optical film according to claim 6 or 7.
The optical film according to any one of claims 1 to 5, which has a light emitting module and an optical film arranged on the display surface side of the light emitting module.
A panel unit used for a display device having a display surface composed of a plurality of panel units.
The optical film according to any one of claims 6 to 8, which has a light emitting module and an optical film arranged on the display surface side of the light emitting module.
The base material layer is arranged on the display surface side of the translucent layer A.
A panel unit used for a display device having a display surface composed of a plurality of panel units.
The panel unit according to claim 9 or 10, wherein the light emitting module includes an LED element.
The LED element has an LED light emitting chip and a resin cover that covers the LED light emitting chip.
The width (W) and depth (D) of the LED element are both 300 μm or less, and the height (H) of the LED element is 200 μm or less.
The panel unit according to claim 11, wherein the arrangement interval of the individual LED elements is 0.03 mm or more and 100 mm or less.
A display device having a display surface composed of a plurality of the panel units according to any one of claims 9 to 12.