Laminated films, laminated sheets, and image display devices

Abstract

To provide a laminated film that offers both excellent visibility and a smooth writing experience. [Solution] A laminated film comprising a base layer, a resin layer formed on the base layer and having an uneven surface on the side opposite to the surface facing the base layer, and a light scattering layer, wherein the light scattering layer satisfies predetermined requirements and, when mounted on the surface of a 217ppi pixel OLED display, is adjusted to display a grayscale image with 256 gradations and an average value of 170 gradations, has a glare value of 15.0 or less measured in accordance with JIS C 1006:2019, has an arithmetic mean roughness Ra of 0.10 μm or more, and has a haze of 15.0% or more measured after removing external haze.

Description

[Technical Field]

[0001] This disclosure relates to laminated films, laminated sheets, and image display devices. [Background technology]

[0002] Films with an uneven surface are widely used in applications such as water-repellent films, anti-glare films, and films that improve the writing feel of touch panels.

[0003] For example, Patent Document 1 discloses a surface material for a pen input device, which has an uneven surface that is input by a pen, wherein the uneven surface has an absolute height of 1.0 μm or more when measured by a scanning white light interference microscope, and the surface roughness Sa value in the range where the absolute height of the uneven surface is less than 1.0 μm when measured by the microscope is set to a value in the range of 0.10 to 0.16. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-022067 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] The surface material for a pen input device described in Patent Document 1 has a good writing feel and can suppress a certain degree of glare. However, after further investigation by the present inventors, they realized that when this surface material is attached to a higher-resolution display, glare occurs, which can reduce visibility.

[0006] This disclosure aims to provide a laminated film that achieves both good visibility and good writing feel. It also aims to provide a laminated sheet containing the laminated film and an image display device. [Means for solving the problem]

[0007] This disclosure concerns the following: [1] The material comprises a base layer, a resin layer formed on the base layer, the surface opposite to the surface facing the base layer having an uneven shape, and a light scattering layer. The light scattering layer satisfies one or more requirements selected from the group consisting of the following requirements (1) to (3): (1) The light scattering layer is provided on the side opposite to the side on which the resin layer is located, as viewed from the substrate layer; (2) The substrate layer is the light scattering layer; (3) The resin layer is the light scattering layer; When mounted on the surface of a 217ppi OLED display, the grayscale image with 256 gradations is adjusted to have an average value of 170 gradations, and the glare value measured in accordance with JIS C 1006:2019 is 15.0 or less. The arithmetic mean roughness Ra of the resin layer is 0.10 μm or more. A laminated film in which the haze content, measured after removing the external haze, is 15.0% or higher. [2] The arithmetic mean roughness Ra is 0.50 μm or more, and the maximum rolling circle height of the resin layer is waviness W. EM The laminated film described in [1], wherein the thickness is 5.00 μm or more. [3] The laminated film described in [1] or [2], wherein the pencil hardness measured in accordance with JIS K 5600-5-4:1999 is H or higher. [4] A laminated film as described in any of [1] to [3], wherein the number of scratches with a width of 0.1 mm or more and a length of 1.0 mm or more resulting from the abrasion resistance test is 5 or less. [5] A laminated film as described in any of [1] to [4], wherein the total light transmittance is 85.0% or higher. [6] A laminated film according to any of [1] to [5], wherein the haze is 20.0 to 80.0%. [7] The laminated film according to any one of [1] to [6], wherein the resin layer contains fine particles. [8] The laminated film according to [7], wherein the average particle diameter of the fine particles is 0.1 to 16.0 μm. [9] The laminated film according to [7] or [8], wherein the difference between the refractive index of the base resin contained in the resin layer and the refractive index of the fine particles is 0.05 to 0.20.

[10] The laminated film according to any one of [1] to [9], wherein the resin layer contains nanoparticles having an average particle diameter of 200 nm or less.

[11] The laminated film according to any one of [1] to

[10] , wherein the resin layer is a writing feel improving layer.

[12] The laminated film according to any one of [1] to

[11] , wherein the base material layer is a polyester film.

[13] The laminated film according to any one of [1] to

[12] , wherein the light scattering layer contains a resin and fine particles.

[14] The laminated film according to

[13] , wherein the resin is a polymer of one or more selected from the group consisting of dipentaerythritol hexa (meth) acrylate and ethoxylated trimethylolpropane tri (meth) acrylate and epoxy (meth) acrylate.

[15] The laminated film according to

[13] or

[14] , wherein the fine particles contain silica fine particles.

[16] The laminated film according to any one of [1] to

[15] , which is a writing feel improving film.

[17] The laminated film according to any one of [1] to

[16] , which is a writing feel improving film for a touch panel.

[18] A laminated sheet having the laminated film according to any one of [1] to

[17] and a protective film disposed on at least one side of the laminated film.

[19] A laminated sheet having a laminated film according to any one of [1] to

[17] and an adhesive layer disposed on at least one side of the laminated film.

[20] An image display device comprising a laminated film as described in any of [1] to

[17] . [Effects of the Invention]

[0008] This disclosure provides a laminated film that achieves both good visibility and good writing feel. Furthermore, a laminated sheet and an image display device including the laminated film of this disclosure are also provided. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic cross-sectional view of a laminated film, which is one aspect of the present disclosure. [Figure 2] This is a schematic cross-sectional view of a laminated film, which is one aspect of the present disclosure. [Figure 3] This is a schematic cross-sectional view of a laminated film, which is one aspect of the present disclosure. [Figure 4] This is a schematic cross-sectional view of a laminated sheet, which is one aspect of the present disclosure. [Figure 5] This is a schematic cross-sectional view of a laminated sheet, which is one aspect of the present disclosure. [Modes for carrying out the invention]

[0010] The following describes specific embodiments of this disclosure, but each configuration and combination thereof in each embodiment is merely an example, and additions, omissions, substitutions, and other modifications can be made as appropriate without departing from the spirit of this disclosure. This disclosure is not limited by the embodiments. Furthermore, each aspect disclosed herein can be combined with any other features disclosed herein.

[0011] In this disclosure, "X~Y" indicating a range means "X or greater and Y or less". Furthermore, when numerical ranges expressed as "X~Y" or "X or greater and Y or less" are listed in stages (for example, in preferred order), the upper and lower limits of each numerical range can be any combination.

[0012] In this disclosure, any phrase such as "one or more selected from the group consisting of X, Y, and Z" means any of X, Y, Z, a combination of X and Y, a combination of X and Z, a combination of Y and Z, or a combination of X, Y, and Z.

[0013] In this disclosure, any mention of "X such as x1, x2, and x3" is merely an example of X, and does not imply that X is limited to x1, x2, and x3.

[0014] 1. Laminated film The laminated film of this disclosure comprises a substrate layer, a resin layer formed on the substrate layer and having an uneven surface on the side opposite to the surface facing the substrate layer, and a light scattering layer. The light scattering layer satisfies one or more requirements selected from the group consisting of the following requirements (1) to (3). (1) The light scattering layer is provided on the side opposite to the side where the resin layer is located, as viewed from the substrate layer. (2) The substrate layer is a light scattering layer. (3) The resin layer is a light scattering layer. With the laminated film mounted on the surface of a 217ppi pixel OLED display, the glare value measured in accordance with JIS C 1006:2019 is 15.0 or less when the grayscale image with 256 gradations is adjusted to have an average value of 170 gradations. The arithmetic mean roughness Ra of the resin layer is 0.10 μm or more. The haze measured after removing external haze is 15.0% or more.

[0015] Figure 1 is a schematic cross-sectional view of a laminated film according to one aspect of the present disclosure. In Figure 1, the laminated film 10 comprises a base layer 11, a resin layer 13 having an uneven surface 13a on the side opposite to the surface facing the base layer, and a light scattering layer 14 provided on the side opposite to the side where the resin layer is located when viewed from the base layer. That is, in Figure 1, the light scattering layer fulfills the above requirements (1) is satisfied. The laminated film 10 may include other layers (not shown) as described later. Also, in Figure 1, the resin layer 13 has an uneven surface 13a on the side opposite to the surface in contact with the base layer.

[0016] In this disclosure, "formed on layer X" includes not only being formed directly above layer X (i.e., adjacent to layer X), but also being formed on layer X via any other layer.

[0017] 1-1. Physical properties of laminated films 1-1-1. Glare Value When the laminated film is attached to the surface of a 217ppi pixel OLED display, and adjusted to display a grayscale image with 256 gradations and an average value of 170 gradations, the glare value measured in accordance with JIS C 1006:2019 is 15.0 or less. A 217ppi pixel OLED display is a high-definition display. The glare value is measured using the brightness distribution between gradations, from a state without scattering to a state with scattering added. Therefore, if the center value of brightness in the state without scattering is too biased towards the low or high gradation side, accurate measurement is not possible. By adjusting the film attached to the surface of the display to display a grayscale image with 256 gradations and an average value of 170 gradations, the glare value can be evaluated accurately.

[0018] When the glare value is within the above range, a laminated film with good visibility is obtained. In other words, the laminated film is preferably a film for touch panels. Furthermore, as described later, the laminated film is preferably a film that improves writing feel. Therefore, it is even more preferable that the laminated film is a film that improves writing feel for touch panels. The laminated film of this disclosure is particularly suitable as a film that improves writing feel for touch panels because it achieves both good visibility and good writing feel. The glare value is preferably 12.0 or less, more preferably 9.0 or less, and even more preferably 6.5 or less. The lower limit of the glare value is not particularly limited, but the closer the glare value is to 0, the better. That is, the glare value is preferably 0.0 or more. The glare value may also be 2.0 or more, or 4.0 or more. The range of the glare value may be, for example, 0.0 to 15.0, 2.0 to 15.0, 4.0 to 15.0, 0.0 to 12.0, 2.0 to 12.0, 4.0 to 12.0, 0.0 to 9.0, 2.0 to 9.0, 4.0 to 9.0, 0.0 to 6.5, 2.0 to 6.5, and 4.0 to 6.5.

[0019] The glare value can be adjusted by changing the haze value measured after removing the external haze. A more specific method for measuring glare will be described later.

[0020] 1-1-2. Haze measured after removing external haze. For laminated films, the haze measured after removing the external haze is 15.0% or higher. Hereafter, the haze measured after removing the external haze will also be referred to as internal haze. Internal haze is obtained by obtaining an evaluation sample from which external haze has been removed by laminating an optically transparent adhesive film to both sides of the laminated film, and then measuring the haze of the evaluation sample using a haze meter (HM-150L2N, manufactured by Murakami Color Technology Laboratory Co., Ltd.) in accordance with JIS K 7136:2000 (Plastics - Method for determining haze of transparent materials, established February 20, 2000). A more specific measurement method will be described later.

[0021] Haze is a physical property that represents the transparency of a film; a high haze value indicates low transparency. Furthermore, haze consists of external haze and internal haze. External haze is the product of... The haze originates from the surface structure of the layered film, while the internal haze originates from the internal structure of the laminated film. An internal haze within the above range indicates that light scattering is more likely to occur within the laminated film. Therefore, an internal haze within the above range makes it easier for the glare value to fall within the above range. As a result, a laminated film with good visibility is obtained.

[0022] The internal haze is preferably 22.0% or more, more preferably 30.0% or more, and even more preferably 39.0% or more. There is no particular upper limit to the internal haze, but from the viewpoint of ensuring transparency sufficient for application to optical applications such as touch panel writing-enhancing films, it is preferably 50.0% or less, and more preferably 45.0% or less. The range of internal haze may be, for example, 15.0-50.0%, 22.0-50.0%, 22.0-45.0%, 30.0-45.0%, and 39.0-45.0%. The internal haze can be adjusted by changing the materials used in each layer constituting the laminated film, for example, the type of base resin in the resin layer, the arithmetic mean roughness of the resin layer, the material of the substrate layer, and the material of the light scattering layer.

[0023] 1-1-3. Hayes The haze of the laminated film is not particularly limited, but is preferably 20.0% or more, more preferably 30.0% or more, even more preferably 43.0% or more, and particularly preferably 53.0% or more, as it facilitates good visibility. The upper limit of the haze is not particularly limited, but is preferably 80.0% or less, more preferably 70.0% or less, and even more preferably 63.0% or less. The range of haze may be, for example, 20.0-80.0%, 30.0-80.0%, 30.0-70.0%, 30.0-63.0%, 43.0-63.0%, and 53.0-63.0%. Haze can be adjusted by changing the materials used in each layer constituting the laminated film, such as the type of base resin in the resin layer, the arithmetic mean roughness of the resin layer, the material of the substrate layer, and the material of the light scattering layer. The method for measuring haze will be described later.

[0024] 1-1-4. Arithmetic mean roughness Ra of the resin layer The arithmetic mean roughness Ra of the resin layer is 0.10 μm or greater. When Ra is within the above range, a laminated film with good writing feel is obtained. In other words, the resin layer can be said to be a writing feel improving layer. Furthermore, it is preferable that the laminated film is a writing feel improving film. On the other hand, when Ra is within the above range, glare is likely to occur when the laminated film is attached to a high-definition display, and visibility tends to decrease. With the laminated film of this disclosure, good visibility can be obtained even when Ra is within the above range. Ra is preferably 0.30 μm or greater, more preferably 0.50 μm or greater, and even more preferably 0.70 μm or greater. There is no particular upper limit to Ra, but the value of Ra may be 1.00 μm or less, and preferably 0.90 μm or less. The range of Ra values ​​may be, for example, 0.10 to 1.00 μm, 0.30 to 1.00 μm, 0.50 to 1.00 μm, 0.70 to 1.00 μm, and 0.70 to 0.90 μm.

[0025] The Ra value can be adjusted to the above range by a method corresponding to the method of forming the protrusions. For example, when forming the protrusions by pressing, select a stamper corresponding to the desired arithmetic mean roughness; when forming the protrusions by etching, select an etching mask having a pattern corresponding to the desired arithmetic mean roughness; when forming the protrusions by incorporating fine particles described later into the resin layer, set the average particle size and content of the fine particles to the range described later; thereby, Ra can be adjusted to the above range. The method for measuring the Ra value will be described later.

[0026] 1-1-5. Rolling circle of the resin layer, maximum height, and waviness W EM Maximum rolling circle height undulation W of the resin layer EM is a physical property representing the degree of undulation of the surface of the resin layer. A large value of W EM indicates large irregularities on the resin layer, and a small value of W EM indicates small irregularities on the resin layer. W EM Although the value of is not particularly limited, it is preferably 5.00 μm or more, more preferably 6.00 μm or more, and even more preferably 7.00 μm or more In the above range, when the laminated film is applied to a writing feeling improvement film for a touch panel, when inputting with a pen on the surface of the laminated film, when the pen catches on each holding area and separates, the amplitude of the pen vibration and the acceleration of the pen vibration caused by the pen vibration are close to the amplitude of the pen vibration and the acceleration of the pen vibration caused by the pen vibration when writing on paper with a pen, and a writing feeling closer to that of paper can be obtained. Therefore, a laminated film with an even better writing feeling can be obtained.

[0027] W EM Although the upper limit of the value of is not particularly limited, it is preferably 12.00 μm or less, more preferably 11.00 μm or less, and even more preferably 10.00 μm or less. The value range of W EM may be, for example, 5.00 to 12.00 μm, 6.00 to 11.00 μm, 7.00 to 10.00 μm. W EM The value of can be adjusted to the above range by a method according to the method of forming the convex portions. For example, when forming the convex portions by mold pressing, select a stamper according to the desired maximum rolling circle height undulation; when forming the convex portions by etching, select an etching mask having a pattern according to the desired maximum rolling circle height undulation; when forming the convex portions by including fine particles described later in the resin layer, set the average particle size and content of the fine particles to the ranges described later; thus, W EM can be adjusted to the above range. W EM The method for measuring the value of will be described later.

[0028] 1-1-6. Average wobble of the rolling circle of the resin layer EA The rolling circle of the resin layer, arithmetic mean wobble W EA This is a physical property that represents the degree of surface waviness of the resin layer. EA A large value indicates that the resin layer has a large degree of unevenness, W EA A small value indicates that the resin layer has few irregularities. W EA The value of is not particularly limited, but is preferably 0.60 μm or more, and more preferably 0.70 μm or more. When the laminated film is applied to a touch panel writing-enhancing film, when inputting with a pen on the surface of the laminated film, the amplitude of the pen vibration and the acceleration of the pen due to the pen's vibration when the pen catches on and separates from each holding area becomes close to the amplitude of the pen vibration and the acceleration of the pen when writing with a pen on paper, resulting in a writing feel that is closer to that of writing on paper. Therefore, a laminated film with an even better writing feel can be obtained.

[0029] W EA The upper limit of the value is not particularly limited, but it is preferably 5.00 μm or less, more preferably 2.50 μm or less, even more preferably 1.50 μm or less, and particularly preferably 1.00 μm or less. EA The range of values ​​may be, for example, 0.60 to 5.00 μm, 0.60 to 2.50 μm, 0.70 to 1.50 μm, or 0.70 to 1.00 μm. W EA The value of can be adjusted to the above range by a method corresponding to the method of forming the protrusion. For example, when forming the protrusion by pressing, select a stamper corresponding to the desired arithmetic mean undulation of the rolling circle; when forming the protrusion by etching, select an etching mask having a pattern corresponding to the desired arithmetic mean undulation of the rolling circle; when forming the protrusion by incorporating fine particles described later into the resin layer, set the average particle size and content of the fine particles to the range described later; thereby, W EA The above range can be adjusted. W EAThe method for measuring the value will be described later.

[0030] 1-1-7.Pencil hardness Since the laminated film is expected to be used in applications requiring scratch resistance, such as touch panel writing-enhancing films, it is preferable that it has sufficient pencil hardness. Specifically, the pencil hardness of the laminated film according to this embodiment is preferably H or higher, more preferably 2H or higher, and even more preferably 3H or higher. By having a pencil hardness within the above range, the laminated film can also function as a protective film for image display devices such as touch panels when used in such devices. The upper limit of the pencil hardness of the laminated film according to this embodiment is not particularly limited, but is usually 10H or lower, and may be 9H or lower, or 7H or lower.

[0031] Methods for achieving the above-mentioned pencil hardness of the laminated film include, for example, selecting a hard resin such as (meth)acrylic resin and its crosslinked product as the constituent material of the resin layer; incorporating the nanoparticles described later into the resin layer; and, if the fine particles described later into the resin layer, selecting fine particles of a hard material such as (meth)acrylic resin and its crosslinked product as the fine particles.

[0032] The pencil hardness of laminated films is measured in accordance with JIS K 5600-5-4:1999 (General test methods for paints - Part 5: Mechanical properties of coatings - Section 4: Scratch hardness (pencil method), established April 20, 1999), using a pencil scratch hardness tester (for example, "No. 553-M" manufactured by Yasuda Seiki Seisakusho Co., Ltd.). The test is performed on the resin layer of the laminated film under the following conditions: load of 750g, test speed of 30mm / min, and test distance of 15mm.

[0033] 1-1-8. Scratch resistance For laminated films, it is preferable that the number of scratches with a width of 0.1 mm or more and a length of 1.0 mm or more that occur during the abrasion resistance test is 5 or less. The fewer the number of visible scratches that occur during the abrasion resistance test, the better the scratch resistance of the laminated film, more preferably 3 or less, and even more preferably 0. The abrasion resistance test is performed on the uneven surface of the resin layer of the laminated film using an abrasion wheel (for example, the "CS-10" tapered abrasion wheel manufactured by Daitron Corporation) under the following conditions: load of 750g, sliding distance (one-way, linear sliding) of 5cm, sliding speed of 40 reciprocations / minute, and number of reciprocations of 100. In this disclosure, "visible scratches" means scratches with a width of 0.1 mm or more and a length of 1.0 mm or more.

[0034] 1-1-9.Total light transmittance The total light transmittance of the laminated film is preferably 80.0% or higher, more preferably 85.0% or higher, even more preferably 90.0% or higher, and even more preferably 95.0% or higher, from the viewpoint of ensuring transparency sufficient for optical applications such as touch panel writing-enhancing films. On the other hand, the upper limit of the total light transmittance of the laminated film is not particularly limited, and is usually 100.0% or lower. The total light transmittance can be adjusted, for example, by changing the thickness of the resin layer or the content of fine particles.

[0035] The total light transmittance of the laminated film is measured in accordance with JIS K 7361-1:1997 (Plastics - Test method for total light transmittance of transparent materials - Part 1: Single beam method, established January 20, 1997) using a haze meter (for example, "HM-150L2N" manufactured by Murakami Color Technology Laboratory Co., Ltd.). In this case, the uneven surface of the resin layer is considered the light-receiving surface.

[0036] 1-2. Base material layer The base layer is not particularly limited and can be appropriately selected depending on the application of the laminated film. For example, the base layer can be a plastic film or a glass plate, and a plastic film is preferred due to its high affinity with the resin layer and interlayer adhesion. The base layer may have a single-layer structure or a multi-layer structure.

[0037] Examples of plastic films include polyester films such as polyethylene terephthalate film, polybutylene terephthalate film, and polyethylene naphthalate film; polyolefin films such as polyethylene film, polypropylene film, and polymethylpentene film; cellulosic films such as cellophane, diacetylcellulose film, triacetylcellulose film, and acetylcellulose butyrate film; vinyl resin films such as polyvinyl chloride film, polyvinylidene chloride film, polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, and polystyrene film; polycarbonate film; polysulfone film; polyetheretherketone film; polyethersulfone film; polyetherimide film; fluororesin film; polyamide film; (meth)acrylic resin film; polyurethane resin film; cyclic olefin polymer films such as norbornene polymer films; and cyclic conjugated diene polymer films. These plastic films can also be used as a base layer by laminating two or more layers.

[0038] Of these plastic films, polyester film is preferred as the base layer due to its high transparency and strength, and polyethylene terephthalate film is more preferred.

[0039] The substrate layer may be subjected to any surface treatment to improve interlayer adhesion with adjacent layers. Examples of surface treatment methods include corona treatment, flame treatment, UV ozone treatment, chromic acid treatment, and sandblasting.

[0040] The thickness of the substrate layer is not particularly limited, but is preferably 50 μm or more, more preferably 75 μm or more, even more preferably 100 μm or more, and also preferably 200 μm or less, more preferably 175 μm or less, and even more preferably 150 μm or less. In other words, preferred ranges for the substrate layer include, for example, 50 to 200 μm, 75 to 175 μm, and 100 to 150 μm.

[0041] By setting the thickness of the base layer to above the lower limit, the aforementioned pencil hardness can be more easily achieved, and when the laminated film is used as a touch panel writing-enhancing film, the influence of the adhesive used for attachment to the touch panel on the writing feel and the hardness of the touch panel surface can be reduced. Furthermore, by setting the thickness of the base layer to below the upper limit, appropriate flexibility can be obtained, thereby improving the ease of handling of the laminated film according to this embodiment.

[0042] 1-3. Resin layer The resin layer is a layer formed on the base layer and has an uneven surface on the side opposite to the surface facing the base layer. The uneven surface of the resin layer is the layer that comes into contact with the stylus when the laminated film according to this embodiment is used as a touch-pen for improving writing feel for touch panels, so it is preferable that it be the outermost surface of the laminated film, and therefore, it is preferable that no layer is formed on the surface of the resin layer opposite to the surface facing the base layer.

[0043] The method for forming the resin layer is not particularly limited as long as a desired uneven surface can be formed. Examples include a method in which a resin layer without an uneven surface is formed on a substrate layer by extrusion molding, coating, etc., and then an uneven shape is formed on the surface of the resin layer opposite to the substrate layer by a method such as stamping and etching using a stamper; and a method in which a coating composition containing fine particles having a shape corresponding to the protrusions is applied onto the substrate layer, as shown in the examples described later.

[0044] The materials constituting the resin layer are not particularly limited and may consist only of a base resin, or may include optional components such as fine particles and nanoparticles described later, in addition to the base resin.

[0045] The base resin included in the resin layer is preferably a polymer of a polyfunctional monomer having 2 to 8 polymerizable groups, and more preferably a polymer of a polyfunctional (meth)acrylate having 2 to 8 (meth)acryloyl groups. The base resin may be a homopolymer, or a copolymer obtained by copolymerizing any two or more monomers in any ratio.

[0046] Examples of polyfunctional (meth)acrylates include alkylene glycol di(meth)acrylates such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and hexanediol di(meth)acrylate; (poly)oxyalkylene glycol di(meth)acrylates such as diethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and polyoxytetramethylene glycol di(meth)acrylate; tricyclodecanedimethanol di(meth)acrylate and adamantane di(meth)acrylate. Examples include di(meth)acrylates having bridged cyclic hydrocarbon groups such as acrylate; tri(meth)acrylates such as glycerin tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and ethoxyltrimethylolpropane tri(meth)acrylate; tetra(meth)acrylates such as pentaerythritol tetra(meth)acrylate; penta(meth)acrylates such as dipentaerythritol penta(meth)acrylate; and hexa(meth)acrylates such as dipentaerythritol hexa(meth)acrylate. Of these, one or more selected from the group consisting of dipentaerythritol hexa(meth)acrylate and ethoxyltrimethylolpropane tri(meth)acrylate are preferred as the polyfunctional (meth)acrylate.

[0047] The resin layer preferably contains fine particles. Here, Figure 2 shows a schematic cross-sectional view of one embodiment of a laminated film having a resin layer containing fine particles. In the laminated film 10 shown in Figure 2, the fine particles 13b are dispersed in the resin layer and held in the resin layer 13, and while covered with the resin material 13c, a portion of them protrudes from the side of the resin layer 13 opposite to the base layer 11, forming convex portions 13d that reflect the shape of the fine particles 13b. Then, a surface 13a is formed by multiple convex portions 13d.

[0048] From the viewpoint of making it easier to set the arithmetic mean roughness Ra of the resin layer within the above range, the average particle size of the fine particles is preferably 0.1 μm or more, more preferably 1.0 μm or more, even more preferably 3.0 μm or more, even more preferably 6.0 μm or more, and also preferably 16.0 μm or less, more preferably 12.0 μm or less, and even more preferably 10.0 μm or less. That is, preferred ranges for the average particle size of the fine particles include, for example, the ranges of 0.1 to 16.0 μm, 1.0 to 16.0 μm, 3.0 to 12.0 μm, and 6.0 to 10.0 μm.

[0049] In this disclosure, "average particle size" refers to the median diameter (D 50 This means that the particle size distribution is measured by a laser diffraction scattering particle size distribution analyzer.

[0050] The shape of the fine particles is not particularly limited, but is preferably spherical. In this disclosure, "spherical" does not mean only perfectly spherical, but also includes shapes with a circular, approximately circular, elliptical, or approximately elliptical cross-section, such as oblong and oblate spheres. However, the fine particles contained in the resin layer are preferably perfectly spherical or approximately spherical. This is because the shape of the fine particles is reflected in the shape of the protrusions. If the fine particles are perfectly spherical or approximately spherical, they can disperse the impact and reduce wear when an impact is applied by contact with a pointed object such as a stylus, thereby improving the scratch resistance of the laminated film.

[0051] Materials constituting the fine particles include (meth)acrylic resins, melamine resins, acrylic-styrene copolymers, polycarbonate resins, polyethylene resins, polystyrene resins, and benzoguanamine resins, as well as crosslinked products thereof. The fine particles are preferably (meth)acrylic resin particles, more preferably crosslinked (meth)acrylic resin particles, and even more preferably crosslinked polymethyl methacrylate particles (for example, "Techpolymer SSX series" manufactured by Sekisui Chemical Co., Ltd.) due to their excellent transparency and strength.

[0052] When the resin layer contains fine particles, the content of fine particles in the resin layer is preferably 1 part by mass or more, more preferably 2 parts by mass or more, even more preferably 3 parts by mass or more, even more preferably 4 parts by mass or more, and also preferably 20 parts by mass or less, more preferably 15 parts by mass or less, even more preferably 10 parts by mass or less, and even more preferably 5 parts by mass or less. In other words, when the resin layer contains fine particles, preferred ranges for the content of fine particles in the resin layer relative to 100 parts by mass of the base resin include, for example, 1 part by mass or more and 20 parts by mass or less, 2 parts by mass or more and 15 parts by mass or less, 3 parts by mass or more and 10 parts by mass or less, and 4 parts by mass or more and 5 parts by mass or less.

[0053] By setting the content of fine particles in the resin layer within the above range, it becomes easier to adjust the arithmetic mean roughness Ra to the preferred range described above.

[0054] Preferably, the refractive index of the fine particles is the same as or approximately the refractive index of the base resin. More specifically, the difference between the refractive index of the base resin and the refractive index of the fine particles is preferably 0.10 or less, more preferably 0.05 or less, even more preferably 0.03 or less, and usually 0.00 or more. That is, preferred ranges for the difference between the refractive index of the base resin and the refractive index of the fine particles include, for example, the ranges of 0.00 to 0.10, 0.00 to 0.05, and 0.00 to 0.03.

[0055] The refractive index of the base resin can be adjusted by changing the material used for the base resin. Similarly, the refractive index of the fine particles can be adjusted by changing the type of fine particles. The difference between the refractive index of the base resin and the refractive index of the fine particles can be adjusted by changing both the refractive index of the base resin and the refractive index of the fine particles. For example, when using a polyfunctional (meth)acrylate polymer as the base resin, including (meth)acrylic resin in the fine particles makes it easier to maintain the refractive index difference within the aforementioned range. By setting the difference between the refractive index of the base resin and the refractive index of the fine particles within the above range, a laminated film with low haze can be obtained.

[0056] The resin layer preferably contains nanoparticles with an average particle size of 200 nm or less (hereinafter sometimes simply referred to as "nanoparticles").

[0057] The average particle size of nanoparticles is typically 200 nm or less, preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 30 nm or less. The lower limit of the average particle size of nanoparticles is not particularly limited, but is preferably 1 nm or more, more preferably 5 nm or more, even more preferably 10 nm or more, and even more preferably 15 nm or more. That is, preferred ranges for the average particle size of nanoparticles include, for example, 1 nm to 200 nm, 5 nm to 100 nm, 10 nm to 50 nm, and 15 nm to 30 nm.

[0058] By incorporating nanoparticles of this size into the resin layer, the abrasion resistance of the uneven surface of the resin layer is improved, and as a result, the scratch resistance of the laminated film can be improved.

[0059] Examples of nanoparticles include silica nanoparticles and alumina particles, and silica nanoparticles are preferred because they are highly effective in improving the wear resistance of the uneven surface of the resin layer.

[0060] When the resin layer contains nanoparticles, the content of nanoparticles in the resin layer is preferably 5 parts by mass or more, more preferably 8 parts by mass or more, even more preferably 10 parts by mass or more, and also preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 20 parts by mass or less, per 100 parts by mass of the base resin. In other words, when the resin layer contains nanoparticles, preferred ranges for the content of nanoparticles in the resin layer per 100 parts by mass of the base resin include, for example, 5 parts by mass or more and 40 parts by mass or less, 8 parts by mass or more and 30 parts by mass or less, and 10 parts by mass or more and 20 parts by mass or less.

[0061] By setting the nanoparticle content in the resin layer within the above range, it is possible to improve the pencil hardness of the laminated film while suppressing the influence of nanoparticles on the arithmetic mean roughness Ra, and while ensuring the transparency and ease of formation of the resin layer. As a result, a laminated film with excellent scratch resistance can be obtained.

[0062] The thickness of the resin layer is not particularly limited, but is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and also preferably 7 μm or less, more preferably 6 μm or less, and even more preferably 5 μm or less. The thickness of the resin layer may be 2 to 7 μm, 3 to 6 μm, or 4 to 5 μm.

[0063] By setting the thickness of the resin layer to above the lower limit, it becomes easier to impart sufficient pencil hardness to the laminated film. By setting the thickness of the resin layer to below the upper limit, sufficient haze can be secured, resulting in anti-glare properties and improved visibility. Furthermore, especially when forming protrusions by incorporating fine particles into the resin layer, setting the thickness of the resin layer to below the upper limit prevents the fine particles from becoming embedded within the resin layer, resulting in the formation of protrusions that reflect the shape of the fine particles. Therefore, when this laminated film is used as a touch panel writing-enhancing film, it becomes easier to achieve a good writing feel similar to writing on paper with a writing instrument.

[0064] In this disclosure, "thickness of the resin layer" means the distance between the surface of the resin layer opposite to the uneven surface and the zero plane (average plane) described above. "Thickness of the resin layer" does not include the thickness of layers other than the resin layer, such as the base layer and other layers described later.

[0065] The resin layer may contain any additives as long as they do not impair the effects of the present disclosure. Examples of optional additives include fluorine-based antifouling additives, photopolymerization initiators, ultraviolet absorbers, antioxidants, light stabilizers, antistatic agents, silane coupling agents, anti-aging agents, thermal polymerization inhibitors, surfactants, preservative stabilizers, plasticizers, lubricants, defoamers, wettability improvers, and coating surface improvers. When the resin layer contains any additives, the amount added is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 1 part by mass or less, and usually greater than 0 parts by mass, per 100 parts by mass of the base resin.

[0066] 1-4.Light scattering layer A light-scattering layer is a layer that scatters incident light. When a laminated film has such a light-scattering layer, light is more easily scattered within the laminated film. As a result, the internal haze tends to fall within the aforementioned range. Consequently, a laminated film with good visibility is achieved. The light scattering layer satisfies one or more requirements selected from the group consisting of the following requirements (1) to (3). (1) The light scattering layer is provided on the side opposite to the side where the resin layer is located, as viewed from the substrate layer. (2) The substrate layer is a light scattering layer. (3) The resin layer is a light scattering layer.

[0067] As described above, in Figure 1, the light scattering layer satisfies requirement (1) above. By providing the light scattering layer on the side opposite to the resin layer when viewed from the substrate layer, a laminated film is created that achieves both good writing feel from the resin layer and good visibility from the light scattering layer. Furthermore, by providing the light scattering layer as a layer separate from the resin layer, it becomes easier to achieve both good visibility from the light scattering layer and good writing feel from the resin layer. The method for forming the light scattering layer that satisfies requirement (1) is not particularly limited, and examples include forming the light scattering layer on the side of the substrate layer opposite to the side where the resin layer is located, by extrusion molding, coating, etc.

[0068] Figure 3 is a schematic cross-sectional view of a laminated film according to one aspect of the present disclosure. In Figure 3, the laminated film 10 comprises a base layer 11 and a resin layer 13 whose surface opposite to the surface facing the base layer has an uneven surface 13a. In Figure 3, for example, the base layer 11 may be a light scattering layer, the resin layer 13 may be a light scattering layer, or both the base layer 11 and the resin layer 13 may be light scattering layers. If the base layer 11 is a light scattering layer, the light scattering layer satisfies requirement (2) above. If the resin layer 13 is a light scattering layer, the light scattering layer satisfies requirement (3) above. If both the base layer 11 and the resin layer 13 are light scattering layers, the light scattering layer satisfies requirements (2) and (3) above. Furthermore, in Figure 1, the base layer 11 may be a light scattering layer, the resin layer 13 may be a light scattering layer, or both the base layer 11 and the resin layer 13 may be light scattering layers. In other words, the laminated film may have multiple light scattering layers.

[0069] If the light scattering layer satisfies requirement (2) above, the resulting laminated film will have both good writing feel from the resin layer and good visibility from the light scattering layer. Furthermore, by providing a light scattering layer as a separate layer from the resin layer, it becomes easier to achieve both good visibility from the light scattering layer and good writing feel from the resin layer. If the light scattering layer satisfies requirement (3) above, the resulting laminated film will have both a good writing feel due to the resin layer and good visibility due to the light scattering layer.

[0070] The material constituting the light scattering layer is not particularly limited. For example, it may contain any component such as resin, the fine particles and nanoparticles described above. The resin is preferably a polymer of a polyfunctional monomer having 2 to 8 polymerizable groups, and more preferably a polymer of a polyfunctional (meth)acrylate having 2 to 8 (meth)acryloyl groups. The resin may be a homopolymer, or a copolymer obtained by copolymerizing any two or more monomers in any ratio. Specifically, the polyfunctional monomers described in the section on the resin layer above can be used.

[0071] Furthermore, in the light scattering layer, it is particularly preferable to use epoxy (meth)acrylate as the monomer, and even more preferable to use epoxy acrylate. Specifically, it is particularly preferable that the resin is a polymer of epoxy (meth)acrylate and one or more selected from the group consisting of dipentaerythritol hexa(meth)acrylate and ethoxyl trimethylolpropane tri(meth)acrylate. By using epoxy (meth)acrylate, the refractive index of the light scattering layer can be adjusted, making it easier to keep the internal haze within the above range.

[0072] For every 100 parts by mass of polyfunctional monomers, the amount of epoxy (meth)acrylate is preferably 5.0 to 25.0 parts by mass, and more preferably 10.0 to 20.0 parts by mass. Within this range, the refractive index of the light scattering layer becomes more favorable, and it becomes easier to maintain the internal haze within this range. For every 100 parts by mass of the polyfunctional monomers, the amount of one or more selected from the group consisting of pentaerythritol hexa(meth)acrylate and ethoxyl trimethylolpropane tri(meth)acrylate is preferably 75.0 to 95.0 parts by mass, and more preferably 80.0 to 90.0 parts by mass.

[0073] When the light scattering layer contains resin and fine particles, the difference between the refractive index of the resin and the refractive index of the fine particles is preferably 0.05 to 0.20, and more preferably 0.05 to 0.15. Within this range, it becomes easier to adjust the internal haze to this range. As a result, a laminated film with good visibility is more likely to be obtained.

[0074] The content of fine particles in the light scattering layer is not particularly limited, but is preferably 10.0 to 50.0% by mass, more preferably 15.0 to 40.0% by mass, even more preferably 20.0 to 40.0% by mass, and particularly preferably 30.0 to 40.0% by mass. When the content of fine particles is within the above range, it becomes easier to adjust the value of the internal haze to within that range. The content of fine particles in the light scattering layer can be adjusted by changing the content of fine particles relative to 100 parts by mass of solid content in the coating composition for the light scattering layer.

[0075] The fine particles preferably contain one or more particles selected from the group consisting of silica fine particles and alumina fine particles, and more preferably contain silica fine particles. Furthermore, it is even more preferable that the fine particles are silica fine particles. The average particle size of the fine particles is not particularly limited, but is preferably, for example, 1.0 to 5.0 μm, 1.0 to 4.0 μm, or 1.5 to 3.5 μm. This range makes it easier to adjust the internal haze to the above range.

[0076] The shape of the silica nanoparticles is not particularly limited, but they are preferably spherical. In this disclosure, "spherical" does not mean only perfectly spherical, but also includes shapes with a circular, approximately circular, elliptical, or approximately elliptical cross-section, such as oblong and oblate spheres, but the silica nanoparticles contained in the light scattering layer are preferably perfectly spherical or approximately perfectly spherical. Such a shape makes it easier for the silica nanoparticles to settle inside the light scattering layer. As a result, the internal haze tends to become larger.

[0077] The amount of silica fine particles per 100 parts by mass of fine particles is not particularly limited, but is preferably 80 to 100 parts by mass, and more preferably 90 to 100 parts by mass.

[0078] If the light scattering layer satisfies requirement (2) above, the material of the substrate layer described above may be used, or the resin or fine particles described above may be used. If the light scattering layer satisfies requirement (3) above, the resin layer material described above may be used, or the resin or fine particles described above may be used.

[0079] The thickness of the light scattering layer is not particularly limited, but is preferably 2 μm or more, more preferably 3 μm or more, even more preferably 4 μm or more, and also preferably 7 μm or less, more preferably 6 μm or less, and even more preferably 5 μm or less. The thickness of the light scattering layer may be 2 to 7 μm, 3 to 6 μm, or 4 to 5 μm. Within the above ranges, it becomes easier to adjust the internal haze to the above ranges.

[0080] 1-5. Other layers The laminated film may have other layers besides those described above, as long as they do not impair the effects of the present disclosure. Examples of other layers include a primer layer for improving the adhesion between the substrate layer and the resin layer.

[0081] 2. Laminated sheet with protective film A second embodiment of this disclosure is a laminated sheet having a laminated film according to the first embodiment and a protective film disposed on at least one side of the laminated film. That is, the laminated sheet has a protective film disposed on one or both sides of the laminated film.

[0082] The protective film is not particularly limited and includes, for example, polyester films such as polyethylene terephthalate film; polyolefin films such as polyethylene film; and plastic films such as thermoplastic polyurethane elastomer film.

[0083] The protective film may have an adhesive layer on one side to improve adhesion with the laminated film. The adhesive layer of the protective film can be made from adhesives commonly used in optical film applications. Examples include acrylic adhesives, rubber adhesives, silicone adhesives, urethane adhesives, polyester adhesives, and polyvinyl ether adhesives. Furthermore, the adhesive may be emulsion type, solvent type, or solvent-free type. In addition, the adhesive may or may not have a cross-linked structure. Among these, acrylic adhesives containing (meth)acrylic acid ester polymers are preferred from the viewpoint of exhibiting desired tackiness and having excellent optical properties and durability, and acrylic adhesives containing (meth)acrylic acid ester polymers and having a crosslinked structure are more preferred. In this specification, the term "polymer" also includes the concept of "polymer." Therefore, a more specific example of a protective film is a multilayer film having a polyethylene film and an adhesive layer containing an acrylic adhesive containing a (meth)acrylic acid ester polymer.

[0084] The thickness of the protective film is not particularly limited, but is preferably 30 μm to 125 μm, and more preferably 30 μm to 80 μm.

[0085] Figure 4 shows a schematic cross-sectional view of one embodiment of a laminated sheet. In Figure 4, the laminated sheet 20 has a laminated film 10 and protective films 21 arranged on both sides of the laminated film 10. The laminated film 10 has a base layer 11, a resin layer 13 whose surface opposite to the surface facing the base layer 11 has an uneven surface 13a, and a light scattering layer 14 provided on the side opposite to the side where the resin layer is located when viewed from the base layer. The protective film 21 has a protective film base layer 21a and an adhesive layer 21b. One protective film 21 is attached to the laminated film 10 such that the adhesive layer 21b is in contact with the uneven surface 13a of the laminated film 10. The other protective film 21 is attached to the laminated film 10 such that the adhesive layer 21b is in contact with the surface of the light scattering layer 14 opposite to the base layer 11.

[0086] By placing a protective film on one or both sides of a laminated film to form a laminated sheet, the laminated film can be protected from damage such as friction and scratches. It is preferable that the protective film be placed at least on the uneven surface of the laminated film, as this can suppress wear of the protrusions of the resin layer of the laminated film before use (for example, during distribution).

[0087] 3. Adhesive laminated sheet A third embodiment of this disclosure is a laminated sheet having a laminated film according to the first embodiment and an adhesive layer disposed on at least one side of the laminated film. That is, the laminated sheet is a laminated sheet having an adhesive layer disposed on one or both sides of the laminated film.

[0088] Examples of materials that make up the adhesive layer include (meth)acrylic resin and epoxy resin.

[0089] The thickness of the adhesive is not particularly limited, but is preferably 25 μm to 100 μm, and more preferably 25 μm to 50 μm.

[0090] Figure 5 shows a schematic cross-sectional view of one embodiment of the laminated sheet according to this embodiment. In Figure 5, the laminated sheet 20 has a laminated film 10 and an adhesive layer 23 disposed on one side of the laminated film 10. The laminated film 10 has a base layer 11, a resin layer 13 whose surface opposite to the surface facing the base layer 11 has an uneven surface 13a, and a light scattering layer 14 provided on the side opposite to the side where the resin layer is located when viewed from the base layer. The adhesive layer 23 is attached to the laminated film 10 so as to be in contact with the surface of the light scattering layer 14 of the laminated film 10 that is opposite to the base layer 11.

[0091] By placing an adhesive layer on one or both sides of a laminated film to form a laminated sheet, it becomes easier to attach the laminated film to an image display device or the like. For convenience when using the laminated film as an anti-glare film or a film to improve the writing feel of a touch panel, it is preferable that the adhesive layer be placed on the side of the laminated film 10 opposite to the resin layer 13. Furthermore, in the laminated sheet according to this embodiment, it is also preferable that a release sheet, which is made of plastic film or paper and has been treated with a release agent such as silicone resin, is placed on top of the adhesive layer.

[0092] 4. Image display device A third embodiment of this disclosure is an image display device comprising a laminated film according to the first embodiment. The image display device is not particularly limited and includes, for example, liquid crystal display devices, organic electroluminescent (organic EL) display devices, electronic paper, electronic notebooks (also called digital notebooks or electronic memo pads), and electronic blackboards. When these image display devices are touch panels, as described above, the laminated film according to the first embodiment is preferable because it functions as a film that improves writing feel and has good visibility. Among touch panel type image display devices, electronic paper and electronic notebooks (also called digital notebooks or electronic memo pads) are particularly preferred.

[0093] In this embodiment, the image display device preferably has the laminated film according to the first embodiment attached directly or via an adhesive layer to the display surface of the image display device. In this case, the image display device may also have the laminated film attached to the display surface via the adhesive layer of the laminated sheet of the third embodiment. [Examples]

[0094] The present disclosure will be described in detail below with reference to the following embodiments. However, the present disclosure is not limited to the embodiments described below.

[0095] 〔reagent〕 The materials used in the coating composition are as follows: • CAP: Cellulose acetate propionate, manufactured by Eastman (product name: CAP-482-20, refractive index: 1.49) • EBECRYL600: Epoxy acrylate, manufactured by Daicel Ornex Co., Ltd. (Refractive index: 1.56) • DPHA: Dipentaerythritol hexaacrylate, manufactured by Daicel Ornex Co., Ltd. • Omnirad 184: Photopolymerization initiator, manufactured by IGM Resins BV. • MEK: Methyl ethyl ketone · 1-BuOH: 1-butanol • BYK399: Surface modifier, manufactured by BYK. • KE-P250: Silica microparticles, manufactured by Nippon Shokubai Co., Ltd., average particle size: 2.5 μm, perfectly spherical Refractive index: 1.43 • BYK-UV 3519: Silica nanoparticle dispersion (silica nanoparticle content: 40% by mass, average silica nanoparticle particle size: 20 nm, solvent: ethoxyl trimethylolpropane triacrylate), manufactured by BYK. • PGM: Propylene glycol monomethyl ether • Omnirad 127: Photopolymerization initiator, manufactured by IGM Resins BV. • Techpolymer SSX-108: Cross-linked polymethyl methacrylate spherical microparticles (average particle size: 8 μm, refractive index: 1.49), manufactured by Sekisui Chemical Co., Ltd. • KY1203: Fluorine-based antifouling additive (active ingredient concentration: 20% by mass), manufactured by Shin-Etsu Chemical Co., Ltd. • EBECRYL1360: Polymer-based acrylate, manufactured by Daicel Ornex Co., Ltd. • ACA Z322M: Acrylic oligomer, manufactured by Daicel Ornex Co., Ltd. • Omnirad 127: Photopolymerization initiator, manufactured by IGM Resins BV. • RS-90: UV-reactive surface modifier, manufactured by DIC Corporation.

[0096] [Evaluation Method] (Hayes) In accordance with JIS K 7136:2000 (Plastics - Method for determining haze of transparent materials, established February 20, 2000), the haze of the laminated film was measured using a haze meter (HM-150L2N, manufactured by Murakami Color Technology Research Institute Co., Ltd.). The uneven surface of the resin layer was used as the light-receiving surface. Three measurements were taken, and the arithmetic mean was used as the haze value.

[0097] (Internal haze) Optical transparent adhesive film (product name: TD06A-25, manufactured by Tomoegawa Corporation) was laminated to both sides of the laminated film using a rubber roller. The temperature during this process was 23°C. The evaluation samples obtained by lamination were left to stand at 23°C for 24 hours. Then, in accordance with JIS K 7136:2000 (Plastics - Method for determining haze of transparent materials, established February 20, 2000), the haze of the evaluation samples was measured using a haze meter (HM-150L2N, manufactured by Murakami Color Technology Research Institute Co., Ltd.). At this time, the optical transparent adhesive film on the uneven surface side of the resin layer was used as the light-receiving surface. Three measurements were performed, and the arithmetic mean was taken as the internal haze value.

[0098] (Glitter value) The glare value was measured in accordance with JIS C 1006:2019, using an 8-bit (256 gradations) grayscale image with the laminated film attached to the surface of a 217-ppi OLED display, adjusted so that the average value was 170 gradations. Three measurements were taken, and the arithmetic mean was used as the glare value. Furthermore, the following conditions were used to measure the glare level. F-number (aperture value): F8 Measurement distance: 32cm Lens focal length: 12mm

[0099] (Total light transmittance) In accordance with JIS K 7361-1:1997 (Plastics—Test method for total light transmittance of transparent materials—Part 1: Single beam method, established January 20, 1997), the total light transmittance of laminated films was measured using a haze meter (HM-150L2N, manufactured by Murakami Color Technology Laboratory Co., Ltd.). The uneven surface of the resin layer was used as the light-receiving surface.

[0100] (Pencil hardness) The pencil hardness of laminated films was measured using a pencil scratch hardness tester (No. 553-M, manufactured by Yasuda Seiki Seisakusho Co., Ltd.) in accordance with JIS K 5600-5-4:1999 (General test methods for paints - Part 5: Mechanical properties of paint films - Section 4: Scratch hardness (pencil method), established April 20, 1999). The test was performed on the resin layer of the laminated film under the following conditions: load of 750g, test speed of 30mm / min, and test distance of 15mm.

[0101] (Number of scratches after abrasion resistance test) A wear resistance test was conducted on the uneven surface of the resin layer of a laminated film using a Taber abrasion wheel (Daitron Corporation's "CS-10") under the following conditions: load of 750g, sliding distance (one-way, linear sliding) of 5cm, sliding speed of 40 reciprocations / minute, and number of reciprocations of 100. After the abrasion resistance test, the resin layer of the laminated film was observed, and the number of visible scratches was counted.

[0102] (Arithmetic mean roughness Ra of the resin layer, arithmetic mean waviness W of the rolling circle of the resin layer) EM and the maximum height of the rolling circle of the resin layer, waviness W EM ) Arithmetic mean roughness Ra of the resin layer, arithmetic mean waviness W of the rolling circle of the resin layer. EM and the maximum height of the rolling circle of the resin layer, waviness W EM The surface roughness was measured in accordance with JIS B 0601:2013 (Geometric product specifications (GPS) - Surface texture: contour curve method - Terminology, definitions and surface texture parameters, revised March 21, 2013) using a surface roughness measuring instrument (SURFCOM 1400G-12, manufactured by Tokyo Seimitsu Co., Ltd.) under the following conditions. Three measurements were taken, and the arithmetic mean was used as the arithmetic mean roughness Ra value. • Measurement conditions Measurement length: 10mm Measurement speed: 0.3mm / sec Cutoff wavelength (λc): 0.8 mm Radius of the probe tip: 2 μm Cone angle: 90°

[0103] (Visibility) A laminated film was placed on a display and illuminated in a single color (R:G:B=0:255:0). The degree of flicker on the screen was evaluated visually according to the following criteria. The evaluation was conducted by eight trained panelists, and the most frequent evaluation result was used as the visibility evaluation result. A: Very little flickering B: The flickering is weak. C: Strong flickering

[0104] (Writing feel) Eight trained panelists evaluated the writing feel of the resin layer surface using Apple Pencil®, judging resistance, vibration, and tip catch according to the following criteria. The most frequent evaluation result was then used as the writing feel evaluation result.

[0105] Evaluation Criteria <Resistance> A: It provides a moderate amount of resistance when writing, preventing the pen from slipping. B: There is some resistance when writing, but the pen glides within an acceptable range. C: There is little resistance when writing, and the pen glides smoothly. <Vibration> A: A moderate vibration is transmitted to the hand. B: The vibrations transmitted to the hand are slightly weak, or the vibrations transmitted to the hand are slightly strong. C: The vibrations transmitted to the hand are either too weak or too strong. <The pen tip feels rough> A: I don't notice any catching sensation at the tip of the pen. B: There is still a slight feeling of the pen tip catching on something. C: The pen tip catches too much.

[0106] [Example 1] The components listed in Table 1 were mixed. The solid content concentration of the resulting mixture was set to 50% by mass. [Table 1]

[0107] The entire amount of the obtained mixture was mixed with MEK and silica fine particles (product name: KE-P250, manufactured by Nippon Shokubai Co., Ltd.) in the amounts shown in Table 2 to obtain the coating composition for the light scattering layer according to Example 1. [Table 2] In the table, the silica portion indicates the content of silica fine particles per 100 parts by mass of solid content in the coating composition for the light scattering layer.

[0108] The components listed in Table 3 were mixed to obtain a coating composition for the resin layer. [Table 3]

[0109] The obtained coating composition for the light scattering layer was applied to a polyethylene terephthalate film (Mitsubishi Chemical Corporation's "O321E125", thickness: 125 μm) using a wire bar #6, and then heat-treated by leaving it in an oven heated to 80°C for 1 minute to obtain a dried coating film on the substrate layer. Next, the dried coating film on the substrate layer was subjected to ultraviolet irradiation using an ultraviolet irradiation device (Ushio Inc., high-pressure mercury lamp, ultraviolet irradiation dose: 230 mJ / cm²). 2 The material was passed through a UV curing treatment to cure the dried coating film, forming a light-scattering layer on the substrate layer and obtaining a laminate. The thickness of the obtained light-scattering layer was 3 μm.

[0110] Next, the coating composition for the resin layer was applied to the side of the resulting laminate opposite to the side where the light scattering layer is located, as viewed from the substrate layer, using a wire bar #8. The laminate was then heated in an oven preheated to 80°C for 1 minute to obtain a dried coating on the substrate layer. Next, the dried coating on the substrate layer was treated using an ultraviolet irradiation device (manufactured by Ushio Inc., high-pressure mercury lamp, ultraviolet irradiation dose: 230 mJ / cm²). 2 The film was cured by passing it through a UV-curing process to harden the dried coating, forming a resin layer on the substrate layer and obtaining a laminated film. The obtained laminated films were evaluated for various physical properties. The results are shown in Tables 4 and 5. [Table 4] In the table, internal haze represents the haze (%) measured after removing external haze, Ra represents the arithmetic mean roughness (μm), and W EA This shows the arithmetic mean undulation (μm) of the rolling circle, W EM This indicates the maximum height of the rolling circle and the resulting undulation (μm). [Table 5] In the table, the refractive index difference indicates the difference between the refractive index of the base resin and the refractive index of the fine particles.

[0111] [Examples 2-3] Laminated films were prepared in the same manner as in Example 1, except that the composition of the coating composition for the light scattering layer was changed as shown in Table 2, and various physical properties were evaluated. The results are shown in Tables 4 and 5. The thickness of the light scattering layer in Examples 2 and 3 was 3 μm and 3 μm, respectively.

[0112] [Comparative Example 1] Laminated films were prepared in the same manner as in Example 1, except that the light scattering layer was not formed using the coating composition for the light scattering layer, and the composition of the coating composition for the resin layer was changed as shown in Table 6. Various physical properties were then evaluated. The results are shown in Tables 4 and 5. [Table 6]

[0113] [Comparative Example 2] A laminated film was prepared in the same manner as in Example 1, except that a light scattering layer was not formed using a coating composition for the light scattering layer, and various physical properties were evaluated. The results are shown in Tables 4 and 5.

[0114] Examples 1-3 also exhibited good writing performance, demonstrating that they are laminated films that achieve both good visibility and good writing performance. [Explanation of Symbols]

[0115] 10 Laminated film, 11 Substrate layer, 13 Resin layer, 13a Uneven surface, 13b Fine particles, 13c Resin material, 13d Protrusions, 14 Light scattering layer, 20 Laminated sheet, 21 Protective film, 21a Protective film base layer, 21b Adhesive layer, 23 Adhesive layer

Claims

1. The material comprises a base layer, a resin layer formed on the base layer, the surface opposite to the surface facing the base layer having an uneven shape, and a light scattering layer. The light scattering layer satisfies one or more requirements selected from the group consisting of the following requirements (1) to (3): (1) The light scattering layer is provided on the side opposite to the side on which the resin layer is located when viewed from the substrate layer; (2) The substrate layer is the light scattering layer; (3) The resin layer is the light scattering layer; When mounted on the surface of a 217 ppi pixel OLED display, the grayscale image is adjusted to display 256 gradations with an average value of 170 gradations, and the glare value measured in accordance with JIS C 1006:2019 is 15.0 or less. The arithmetic mean roughness Ra of the resin layer is 0.10 μm or more. A laminated film in which the haze content, measured after removing the external haze, is 15.0% or higher.

2. The arithmetic mean roughness Ra is 0.50 μm or more, and the maximum rolling circle height of the resin layer is waviness W. ＥＭ The laminated film according to claim 1, wherein the thickness is 5.00 μm or more.

3. The laminated film according to claim 1, wherein the pencil hardness measured in accordance with JIS K 5600-5-4:1999 is H or higher.

4. The laminated film according to claim 1, wherein the number of scratches with a width of 0.1 mm or more and a length of 1.0 mm or more that occur in an abrasion resistance test is 5 or less.

5. The laminated film according to claim 1, wherein the total light transmittance is 85.0% or more.

6. The laminated film according to claim 1, wherein the haze is 20.0 to 80.0%.

7. The laminated film according to claim 1, wherein the resin layer contains fine particles.

8. The laminated film according to claim 7, wherein the average particle size of the fine particles is 0.1 to 16.0 μm.

9. The laminated film according to claim 7, wherein the difference between the refractive index of the base resin contained in the resin layer and the refractive index of the fine particles is 0.05 to 0.

20.

10. The laminated film according to claim 1, wherein the resin layer contains nanoparticles with an average particle size of 200 nm or less.

11. The laminated film according to claim 1, wherein the resin layer is a writing quality improving layer.

12. The laminated film according to claim 1, wherein the base material layer is a polyester film.

13. The laminated film according to claim 1, wherein the light scattering layer comprises a resin and fine particles.

14. The laminated film according to claim 13, wherein the resin is a polymer of one or more selected from the group consisting of dipentaerythritol hexa(meth)acrylate and ethoxyltrimethylolpropanetri(meth)acrylate and epoxy(meth)acrylate.

15. The laminated film according to claim 13, wherein the fine particles include silica fine particles.

16. The laminated film according to claim 1, which is a film for improving writing feel.

17. The laminated film according to claim 1, which is a film for improving the writing feel of a touch panel.

18. A laminated sheet comprising a laminated film according to any one of claims 1 to 17 and a protective film disposed on at least one side of the laminated film.

19. A laminated sheet comprising a laminated film according to any one of claims 1 to 17 and an adhesive layer disposed on at least one side of the laminated film.

20. An image display device comprising a laminated film according to any one of claims 1 to 17.

Images