Decorative sheet and laminated film

Abstract

Provided is a technology capable of realizing a laminated film having low glossiness, excellent scratch resistance, and excellent adhesion of a surface protective layer. A laminated film (1) comprises a base material film and a surface protective layer (5) provided on the base material film. The surface protective layer (5) includes a cured product of a curable resin composition. The curable resin composition includes a (meth)acrylate, an acrylic acrylate as an adhesion aid, a photopolymerization initiator, and a solvent. The weight average molecular weight of the acrylic acrylate is larger than the weight average molecular weight of the (meth)acrylate.

Description

Decorative sheets and laminated films

[0001] The present invention relates to a curable resin composition and a laminate film.

[0002] Decorative sheets are used for the purpose of decorating the surfaces of interior and exterior materials such as building fixtures, furniture, fixtures, and flooring, i.e., for the purpose of imparting design and durability to these components. Decorative sheets are generally widely used as decorative panels that are attached via an adhesive or the like to the surface of substrates such as wood, wood boards, metal plates, non-combustible boards, paper substrates, and resin substrates.

[0003] Decorative sheets can be given a design by forming patterns such as wood grain or stone grain using various printing methods. Plain decorative sheets without a pattern are sometimes preferred. The choice of whether to have a pattern or not and the type of pattern vary depending on the application and preference.

[0004] The glossiness of the surface is also important for the design of decorative sheets. There are a variety of decorative sheets to choose from depending on the application and preference, ranging from high gloss like a mirror to low gloss that does not reflect light at all.

[0005] As mentioned above, durability is an important function of decorative sheets, along with providing design. Durability is a comprehensive assessment of scratch resistance, stain resistance, and whether these can be maintained over a long period of time. Requirements vary depending on the environment and situation in which the decorative sheet is used, but decorative sheets with high performance are always in demand.

[0006] To impart durability, a surface protective layer is generally formed on the outermost surface of the decorative sheet, and to adjust the aforementioned gloss, particularly to achieve low gloss, a gloss adjuster (matt additive) is generally added to the surface protective layer.

[0007] As such, a decorative sheet that takes into consideration design (low gloss), scratch resistance, and stain resistance is disclosed in, for example, Patent Document 1.

[0008] Japanese Patent Application Publication No. 2019-119138

[0009] An object of the present invention is to provide a technique that makes it possible to realize a decorative sheet that has low gloss, excellent scratch resistance, and excellent adhesion of a surface protective layer.

[0010] According to one aspect of the present invention, there is provided a curable resin composition comprising a (meth)acrylate, an acrylic acrylate as an adhesion aid, a photopolymerization initiator, and a solvent, wherein the weight average molecular weight of the acrylic acrylate is greater than the weight average molecular weight of the (meth)acrylate.

[0011] According to another aspect of the present invention, there is provided a curable resin composition according to the above aspect, wherein the weight average molecular weight of the (meth)acrylate is in the range of 100 or more and 5,000 or less, and the weight average molecular weight of the acrylic acrylate is in the range of 500 or more and 150,000 or less.

[0012] According to yet another aspect of the present invention, there is provided the curable resin composition according to any of the above aspects, wherein a proportion of the adhesion aid in the total of the (meth)acrylate and the adhesion aid is in the range of 5 mass % or more and 90 mass % or less.

[0013] According to yet another aspect of the present invention, there is provided the curable resin composition according to any one of the above aspects, wherein the (meth)acrylate has a functionality of 1 or more and 18 or less.

[0014] According to yet another aspect of the present invention, there is provided the curable resin composition according to any one of the above aspects, wherein the acrylic acrylate has a double bond equivalent in the range of 200 or more and 15,000 or less.

[0015] According to yet another aspect of the present invention, there is provided the curable resin composition according to any one of the above aspects, wherein the (meth)acrylate includes a (meth)acrylate monomer.

[0016] According to yet another aspect of the present invention, there is provided the curable resin composition according to any one of the above aspects, wherein the (meth)acrylate includes an oligomer having 10 or less functionalities.

[0017] According to yet another aspect of the present invention, there is provided the curable resin composition according to any of the above aspects, comprising the photopolymerization initiator in an amount in the range of 0.5 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the total amount of the (meth)acrylate and the acrylic acrylate.

[0018] According to yet another aspect of the present invention, there is provided a curable resin composition according to any of the above aspects, further comprising a light stabilizer.

[0019] According to yet another aspect of the present invention, there is provided the curable resin composition according to any of the above aspects, further comprising particles having an average particle size of 10 μm or less.

[0020] According to yet another aspect of the present invention, there is provided a curable resin composition according to the above aspect, comprising the particles in an amount in the range of 0.5 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the total amount of the (meth)acrylate and the acrylic acrylate.

[0021] According to yet another aspect of the present invention, there is provided a laminate film comprising a base film and a surface protective layer provided on the base film, wherein the surface protective layer is made of a cured product of the curable resin composition according to any of the above aspects.

[0022] According to yet another aspect of the present invention, there is provided the laminate film according to the above aspect, wherein the thickness of the surface protective layer is in the range of 2 μm or more and 20 μm or less.

[0023] According to yet another aspect of the present invention, there is provided the laminate film according to any one of the above aspects, wherein the specular gloss GS(60°) of the surface protective layer is less than 15.0.

[0024] According to yet another aspect of the present invention, there is provided a laminate film according to any one of the above aspects, in which the surface of the surface protection layer has an uneven structure including a plurality of ridge portions, each of which protrudes in a ridge-like shape.

[0025] According to yet another aspect of the present invention, there is provided a laminated film relating to the above aspect, in which at least some of the multiple ridge portions are adjacent to each other in the width direction, and in a cross section parallel to the width direction and the thickness direction of the surface protection layer at the position where at least some of the multiple ridge portions are adjacent to each other in the width direction, the portion where the uneven structure is provided has a sinusoidal shape.

[0026] According to yet another aspect of the present invention, there is provided a decorative material comprising the laminate film according to any one of the above aspects and a substrate to which the laminate film is attached.

[0027] According to yet another aspect of the present invention, there is provided a method for producing a laminated film, comprising: applying the curable resin composition according to any of the above aspects onto a substrate film to form a coating film; irradiating the coating film with light having a wavelength of 200 nm or less; and thereafter irradiating the coating film with ionizing radiation or ultraviolet light having a longer wavelength than the light.

[0028] The present invention provides a technology that makes it possible to realize a decorative sheet that has low gloss, excellent scratch resistance, and excellent adhesion of a surface protective layer.

[0029] Fig. 1 is a cross-sectional view of a decorative material including a laminate film according to one embodiment of the present invention. Fig. 2 is a cross-sectional view of a decorative material including a laminate film according to another embodiment of the present invention. Fig. 3 is a cross-sectional view of a surface protective layer that may be included in the laminate film of Fig. 1 and Fig. 2. Fig. 4 is a microscope image of a surface protective layer included in a laminate film according to one example of the present invention.

[0030] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are more specific embodiments of any of the above aspects. The following items can be incorporated into each of the above aspects, either singly or in combination.

[0031] Furthermore, the embodiments shown below are merely examples of configurations for embodying the technical idea of ​​the present invention, and the technical idea of ​​the present invention is not limited by the materials, shapes, structures, etc. of the components described below. Various modifications can be made to the technical idea of ​​the present invention within the technical scope defined by the claims.

[0032] In the drawings, elements having the same or similar functions are denoted by the same reference numerals, and redundant explanations will be omitted. Furthermore, the drawings are schematic, and the relationship between dimensions in one direction and dimensions in another direction, and the relationship between the dimensions of one member and the dimensions of another member, etc. may differ from the actual relationship.

[0033] <1> Decorative material and decorative sheet Fig. 1 is a cross-sectional view of a decorative material including a laminate film according to one embodiment of the present invention. Fig. 2 is a cross-sectional view of a decorative material including a laminate film according to another embodiment of the present invention. Fig. 3 is a cross-sectional view of a surface protective layer that may be included in the laminate film of Figs. 1 and 2. Fig. 4 is a micrograph of a surface protective layer included in a laminate film according to one example of the present invention.

[0034] The cross section shown in Fig. 3 is a cross section along the thickness direction of the surface protection layer, and the micrograph in Fig. 4 is a plan view photograph obtained by a laser microscope (OLS-4000 manufactured by Olympus Corporation).

[0035] The decorative material 11 shown in Figures 1 and 2 includes a substrate B and a decorative sheet 1 attached thereto. Here, the decorative material 11 is a decorative board. The decorative board may be a flat board, or may be curved or folded. The decorative material 11 may have a shape other than a board.

[0036] Here, the substrate B is a plate material. The plate material is, for example, a wood board, an inorganic board, a metal plate, or a composite board made of multiple materials. The substrate B may have a shape other than a plate.

[0037] The decorative sheet 1 shown in Figures 1 and 2 is a laminated film. Although the terms "sheet" and "film" are sometimes used differently depending on the thickness, these terms will not be used here to distinguish between them based on thickness, and both refer to a thin layer that can be handled independently.

[0038] The decorative sheet 1 shown in Figure 1 includes a raw fabric layer 2, a design layer 3, a surface protective layer 5, and a primer layer 6. The design layer 3 and the surface protective layer 5 are provided, in this order, on one side of the raw fabric layer 2. The primer layer 6 is provided on the other side of the raw fabric layer 2. Here, the base film is a laminate of the raw fabric layer 2 and the design layer 3. In the decorative sheet 1 of Figure 1, one or more of the design layer 3 and the primer layer 6 may be omitted.

[0039] The decorative sheet 1 shown in Figure 2 is similar to the decorative sheet 1 shown in Figure 1, except that it further includes a transparent resin layer 4 and an adhesive resin layer 4b. The transparent resin layer 4 is interposed between the design layer 3 and the surface protective layer 5. The transparent resin layer 4 has an embossed textured pattern (embossed pattern 4a) on the surface facing the surface protective layer. The adhesive resin layer 4b is interposed between the design layer 3 and the transparent resin layer 4. In the decorative sheet 1 of Figure 2, one or more of the design layer 3, adhesive resin layer 4b, transparent resin layer 4, and primer layer 6 may be omitted. Furthermore, the transparent resin layer 4 does not necessarily have to have the embossed pattern 4a.

[0040] The decorative sheet 1 in Figures 1 and 2 may have a structure in which multiple surface protective layers 5 are laminated in order to improve scratch resistance, etc. The decorative sheet 1 in Figure 2 may have a structure in which multiple transparent resin layers 4 are laminated in order to improve scratch resistance, etc. The decorative sheet 1 in Figures 1 and 2 may have another layer interposed between adjacent layers in order to improve adhesion between those layers. Furthermore, the decorative sheet 1 in Figures 1 and 2 may further include one or more layers, such as a concealing layer, between the base layer 2 and the primer layer 6.

[0041] The elements contained in the decorative sheet 1 will be explained below one by one.

[0042] <1.1> Raw Fabric Layer The raw fabric layer 2 or its material can be any material selected from, for example, paper, synthetic resin, synthetic resin foam, rubber, nonwoven fabric, synthetic paper, and metal foil. Examples of paper include tissue paper, titanium paper, and resin-impregnated paper. Examples of synthetic resins include polyethylene, polypropylene, polybutylene, polystyrene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, and acrylic. Examples of rubber include ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene copolymer rubber, styrene-isoprene-styrene block copolymer rubber, styrene-butadiene-styrene block copolymer rubber, and polyurethane. Examples of nonwoven fabric include organic and inorganic nonwoven fabrics. Examples of metals for the metal foil include aluminum, iron, gold, and silver.

[0043] The raw fabric layer 2 may be a sheet made of the same resin composition as the transparent resin layer 4. In this case, the raw fabric layer 2 is obtained by molding a resin material or a resin composition into a film. Examples of molding methods include calendar molding and extrusion molding.

[0044] The raw fabric layer 2 preferably has a colored layer formed by mixing an inorganic pigment with a synthetic resin, and a skin layer formed of a synthetic resin. The skin layer is preferably provided on both sides of the colored layer. When the raw fabric layer 2 is formed by co-extrusion, if the colored layer is the outermost layer, the pigment component contained in the colored layer may bleed and cause contamination of the T-die and transport rolls of the extruder. Therefore, the outermost layer of the raw fabric layer 2 is preferably a skin layer that does not contain a pigment.

[0045] The thickness of the skin layer is preferably in the range of 3 μm to 20 μm. The ratio of the thickness of the skin layer to the thickness of the colored layer is preferably in the range of 1:6 to 1:50. If the ratio of the thickness of the skin layer to the thickness of the colored layer is increased while the thickness of the base layer 2 is kept approximately constant, the hiding power will decrease.

[0046] The thickness of the raw fabric layer 2 is preferably in the range of 50 μm to 150 μm. If the raw fabric layer 2 is thin, the ability to cover unevenness of the base (unevenness) will decrease. If the raw fabric layer 2 is thick, problems such as whitening and cracking may occur during bending.

[0047] The inorganic pigment can be used to impart hiding properties to the base fabric layer 2. Known inorganic pigments, such as titanium oxide, can be used as this inorganic pigment. The base fabric layer 2 containing the inorganic pigment serves to conceal the pattern of the substrate B. To achieve the hiding properties required from the standpoint of the design of the decorative sheet 1, the base fabric layer 2 preferably has a light transmittance of 40% or less. Poor hiding properties may result in the pattern of the design layer 3 appearing to blend with the pattern of the substrate B. By incorporating an inorganic pigment into the base fabric layer 2, a decorative sheet 1 with good hiding properties can be obtained. The amount of inorganic pigment is preferably in the range of 5 to 50 parts by weight per 100 parts by weight of the resin material contained in the base fabric layer 2. A small amount of inorganic pigment reduces hiding properties. An excessive amount of inorganic pigment may cause embrittlement of the base fabric layer 2. Examples of inorganic pigments include natural inorganic pigments and synthetic inorganic pigments. Examples of natural inorganic pigments include earth-based pigments, calcined earth, and mineral pigments. Examples of synthetic inorganic pigments include oxide pigments, hydroxide pigments, sulfide pigments, silicate pigments, phosphate pigments, carbonate pigments, metal powder pigments, and carbon pigments. As the synthetic inorganic pigment, one of natural inorganic pigments and synthetic inorganic pigments may be used, or two or more selected from these may be mixed and used. As the synthetic inorganic pigment, an organic pigment such as carbon black may also be used in combination.

[0048] Additives such as fatty acid metal salts may be added to the material of the raw fabric layer 2 in order to improve the dispersibility of inorganic pigments and the extrusion suitability.

[0049] When a substrate with an inactive surface, such as an olefin-based substrate, is used as the raw fabric layer 2, it is desirable to subject the front and back surfaces of the raw fabric layer 2 to treatment such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, and dichromate treatment.

[0050] <1.2> Pattern Layer A pattern layer 3 for adding a pattern to the decorative sheet 1 can be provided on the surface of the base fabric layer 2. The pattern can be, for example, a wood grain pattern, a stone grain pattern, a sand grain pattern, a tiled pattern, a brickwork pattern, a fabric pattern, a leather-grained pattern, or a geometric figure.

[0051] The design layer 3 may have a single layer structure or a multi-layer structure. In the latter case, the design layer 3 may be formed by laminating as many plates as necessary to express the desired design.

[0052] A solid ink layer (not shown) may be provided between the base fabric layer 2 and the design layer 3. The solid ink layer is provided so as to cover the entire surface of one side of the base fabric layer 2. The solid ink layer has, for example, opacifying properties. The solid ink layer may have a single-layer structure or a multi-layer structure.

[0053] In this way, by making the design layer 3 a multi-layer structure or by combining the design layer 3 with a solid ink layer, various designs can be expressed.

[0054] As the material for the solid ink layer and the design layer 3, for example, a printing ink or a coating agent obtained by dissolving or dispersing a matrix and a coloring agent such as a dye or a pigment in a solvent can be used.

[0055] As the matrix, for example, various synthetic resins such as oil-based nitrocellulose resin, two-component urethane resin, acrylic resin, styrene resin, polyester resin, urethane resin, polyvinyl resin, alkyd resin, epoxy resin, melamine resin, fluorine resin, silicone resin, rubber resin, or a mixture or copolymer of these can be used.

[0056] Examples of colorants that can be used include inorganic pigments such as carbon black, titanium white, zinc white, red iron oxide, yellow lead, iron blue, and cadmium red; organic pigments such as azo pigments, lake pigments, anthraquinone pigments, phthalocyanine pigments, isoindolinone pigments, and dioxazine pigments; and mixtures thereof.

[0057] Examples of the solvent that can be used include toluene, xylene, ethyl acetate, butyl acetate, methyl alcohol, ethyl alcohol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, water, and mixtures thereof.

[0058] Functional additives such as extender pigments, plasticizers, dispersants, surfactants, tackifiers, adhesive aids, drying agents, hardeners, hardening accelerators, and hardening retarders may be added to the materials of the solid ink layer and the pattern layer 3 in order to impart various functions.

[0059] The solid ink layer and the design layer 3 can be formed by various printing methods, such as gravure printing, offset printing, screen printing, electrostatic printing, and inkjet printing. The solid ink layer covers the entire surface of one side of the base layer 2, so it can also be formed by various coating methods, such as roll coating, knife coating, microgravure coating, and die coating. These printing and coating methods may be different for each layer to be formed, but selecting the same method is efficient because it allows for continuous processing.

[0060] The thickness of the design layer 3 is preferably in the range of 3 μm to 20 μm. Increasing the thickness of the design layer 3 increases the visibility of the design. However, if the design layer 3 is made too thick, printing workability decreases and manufacturing costs increase.

[0061] <1.3> Transparent Resin Layer The resin material used as the main component of the transparent resin layer 4 is preferably made of an olefin-based resin. Here, unless otherwise specified, the term "main component" refers to a component that accounts for 90% by mass or more of the target material.

[0062] Examples of olefin resins include polyethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-decene, 12-methyl-1-decene, 13-methyl-1-decene, 14-methyl-1-decene, 15-methyl-1-decene, 16-methyl-1-decene, 17-methyl-1-decene, 18-methyl-1-decene, 19-methyl-1-decene, 20-methyl-1-decene, 21-methyl-1-decene, 22-methyl-1-decene, 23-methyl-1-decene, 24-methyl-1-decene, 25-methyl-1-decene, 26-methyl-1-decene, 27-methyl-1-decene, 28-methyl-1-decene, 29-methyl-1-decene, 30-methyl-1-decene, 31-methyl-1-decene, 32-methyl-1-decene, 33-methyl-1-decene, 34-methyl-1-decene, 35-methyl-1-decene, 36-methyl-1-decene, 37 Examples of the transparent resin layer 4 include a homopolymer of one type of α-olefin, such as 12-ethyl-1-dodecene, and 12-ethyl-1-tetradecene, or a copolymer of two or more types thereof, such as polypropylene or polybutene; or a copolymer of ethylene or an α-olefin with another monomer, such as an ethylene-vinyl acetate copolymer, an ethylene-vinyl alcohol copolymer, an ethylene-methyl methacrylate copolymer, an ethylene-ethyl methacrylate copolymer, an ethylene-butyl methacrylate copolymer, an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer, and an ethylene-butyl acrylate copolymer. When the surface strength of the decorative sheet 1 is to be improved, it is preferable to use a highly crystalline polypropylene for the transparent resin layer 4.

[0063] When the transparent resin layer 4 is provided, its thickness is preferably in the range of 50 μm to 100 μm. If the transparent resin layer 4 is thin, the effect of improving scratch resistance is low, and there is little point in providing the transparent resin layer 4. If the transparent resin layer 4 is thick, the rigidity of the decorative sheet 1 may be too high, which may cause defects such as whitening and cracking during bending.

[0064] The resin composition used as the material for the transparent resin layer 4 may contain, as necessary, various functional additives such as a heat stabilizer, a light stabilizer, an ultraviolet absorber, an antiblocking agent, a catalyst scavenger, a colorant, a light scattering agent, and a gloss adjuster. These various functional additives can be appropriately selected from well-known additives.

[0065] The bonding method and adhesive used to bond the design layer 3 and the transparent resin layer 4 can be selected as appropriate. Examples of bonding methods include lamination methods such as thermal lamination, extrusion lamination, and dry lamination. The adhesive can be selected from acrylic, polyester, and polyurethane materials. In terms of cohesive strength, a two-component curing urethane material that utilizes the reaction between isocyanate and polyol is usually desirable.

[0066] The transparent resin layer 4 may be provided with a concave-convex pattern (embossed pattern 4a) by embossing. The recesses constituting the embossed pattern 4a may be filled with ink to further enhance the design. Methods for providing the embossed pattern 4a include embossing the transparent resin layer 4 after laminating it to the design layer 3, and using a cooling roll provided with a concave-convex pattern to emboss the transparent resin layer 4 simultaneously with extrusion lamination of the transparent resin layer 4 to the design layer 3. Alternatively, a method may be used in which the transparent resin layer 4, which has been embossed simultaneously with extrusion, and the design layer 3 are bonded together by heat or dry lamination.

[0067] To improve adhesion between the design layer 3 and the transparent resin layer 4, an adhesive resin layer 4b may be provided between the design layer 3 and the transparent resin layer 4. Specifically, to achieve further lamination strength in the extrusion lamination method, an adhesive resin layer 4b may be provided between the transparent resin layer 4 and the adhesive. When the adhesive resin layer 4b is provided, lamination can be performed by co-extrusion of the transparent resin layer 4 and the adhesive resin layer 4b. The material of the adhesive resin layer 4b is, for example, polypropylene, polyethylene, acrylic resin, or the like, which has been acid-modified. The thickness of the adhesive resin layer 4b is preferably 2 μm or more to improve adhesive strength.

[0068] 3, the surface protection layer 5 includes a core portion 5A and a plurality of ridge portions 5B each protruding in a ridge shape from one surface of the core portion 5A. These ridge portions 5B form an uneven structure.

[0069] Here, in the decorative sheet 1 according to this embodiment, the term "ridge-like" refers to a convex shape that is linear in plan view. The ridge portions 5B may be curved or linear in plan view, but are preferably curved in view of the fingerprint resistance of the decorative sheet 1. Each ridge portion 5B may be branched or unbranched in plan view. In addition, in the present disclosure, the ridge portions 5B refer to, for example, the portion from the lowest point to the tip of the uneven structure provided on the surface of the surface protective layer 5, and the core portion 5A refers to the portion of the surface protective layer 5 excluding the ridge portions 5B.

[0070] The ridge portions 5B are curved, and at least some of them are adjacent to each other in the width direction, as shown in Fig. 3. At a position where at least some of the ridge portions 5B are adjacent to each other in the width direction, the cross section of the surface protective layer 5 parallel to the width direction and the thickness direction of the surface protective layer 5 has a wave shape, such as a sine wave shape, in the portion where the uneven structure is provided, as shown in Fig. 2.

[0071] The thickness t of the surface protection layer 5 is preferably in the range of 2 μm to 20 μm, and more preferably in the range of 4 μm to 10 μm.

[0072] Here, the thickness of the surface protective layer 5 is the thickness of a layer having the same apparent area and volume as the surface protective layer 5 and a flat surface. The thickness of the surface protective layer 5 is determined, for example, by the following method. First, a cross section parallel to the thickness direction of the surface protective layer 5 and perpendicular to the length direction of the ridge portions 5B is imaged. Next, from this cross-sectional image, the dimension of the surface protective layer 5 in the width direction of the ridge portions 5B and the area of ​​the cross section of the surface protective layer 5 are determined. The thickness of the surface protective layer 5 is a value obtained by dividing this area by the above dimension. Note that the thickness of the coating film made of the surface protective layer coating liquid after drying is equal to the thickness of the surface protective layer 5.

[0073] Here, the surface protective layer 5 is provided so as to face the entirety of one surface of the raw fabric layer 2, but the surface protective layer 5 may be provided so as to face part of one surface of the raw fabric layer 2. For example, the surface protective layer 5 may be provided at one or more positions of the pattern included in the design layer 3, and may be open at the remaining positions of the pattern included in the design layer 3.

[0074] The surface protective layer 5 is made of a cured product of a curable resin composition. The curable resin composition is preferably an ionizing radiation curable resin. Here, "ionizing radiation" refers to charged particle beams such as electron beams. The ionizing radiation curable resin is cured by irradiation with ionizing radiation. The ionizing radiation curable resin can also be cured by irradiation with ultraviolet light. The ionizing radiation curable resin used here is cured by irradiation with light having a wavelength of 200 nm or less, and has a large absorption coefficient for this light.

[0075] The curable resin composition contains a (meth)acrylate, an acrylic acrylate as an adhesion aid, a photopolymerization initiator, and a solvent. Here, the term "(meth)acrylate" is used to include acrylate, methacrylate, and combinations thereof. Also, the term "(meth)acryloyl group" is used to include acryloyl group, methacryloyl group, and combinations thereof.

[0076] The proportion of (meth)acrylate in the curable resin composition is preferably in the range of 10% by mass to 95% by mass, and more preferably in the range of 30% by mass to 80% by mass.

[0077] The number of functional groups of the (meth)acrylate is preferably in the range of 1 to 18, and more preferably in the range of 1 to 10. The curable resin composition preferably contains a (meth)acrylate having two or more functional groups.

[0078] The weight average molecular weight of the (meth)acrylate is preferably in the range of 100 or more and 5,000 or less, and more preferably in the range of 150 or more and 3,500 or less.

[0079] The (meth)acrylate contains, for example, a (meth)acrylate monomer. The (meth)acrylate monomer may be a monofunctional (meth)acrylate monomer, but preferably contains a difunctional or higher functional (meth)acrylate monomer, and more preferably contains a trifunctional or higher functional (meth)acrylate monomer. In order to obtain a surface protective layer 5 with excellent scratch resistance, the (meth)acrylate monomer preferably contains a trifunctional or higher functional (meth)acrylate monomer. In one example, the number of functional groups of the (meth)acrylate monomer is hexafunctional or less.

[0080] The (meth)acrylate monomer preferably contains a repeating unit. This repeating unit is, for example, any one of an ethylene oxide (EO) unit, a propylene oxide (PO) unit, and an ε-caprolactone (CL) unit. The repeating unit is preferably ethylene oxide or propylene oxide. In the (meth)acrylate monomer, the repeating unit may be present between the (meth)acryloyl group and the methylol group in a ring-opened state.

[0081] The number of repetitions of the repeating structure is preferably 6 or more. If a (meth)acrylate with a large number of repetitions is used, the cured film is more likely to expand in the in-plane direction in the first irradiation step described below, and therefore wrinkles corresponding to the ridge portions 5B are more likely to appear on the coating film surface. However, if the number of repetitions is increased, the crosslink density decreases, and the scratch resistance of the surface protective layer 5 decreases.

[0082] The (meth)acrylate may contain a (meth)acrylate oligomer instead of or in addition to the (meth)acrylate monomer. The (meth)acrylate oligomer is, for example, an oligomer obtained by polymerizing the above-mentioned (meth)acrylate monomer. The number of functional groups of the (meth)acrylate oligomer is, for example, 10 or less.

[0083] The acrylic acrylate is an adhesion aid. The weight-average molecular weight of the acrylic acrylate is larger than that of the (meth)acrylate. The weight-average molecular weight of the acrylic acrylate is preferably in the range of 200 to 200,000, more preferably in the range of 500 to 150,000, and even more preferably in the range of 10,000 to 100,000.

[0084] The ratio of the weight average molecular weight of the acrylic acrylate to the weight average molecular weight of the (meth)acrylate is preferably in the range of 0.1 or more and 1,500 or less, and more preferably in the range of 2 or more and 1,000 or less.

[0085] The acrylic acrylate preferably has a double bond equivalent weight in the range of 200 to 15,000, more preferably in the range of 500 to 5,000.

[0086] The proportion of the adhesion aid in the total of the (meth)acrylate and the adhesion aid is preferably in the range of 5% by mass or more and 90% by mass or less, more preferably in the range of 10% by mass or more and 80% by mass or less, and even more preferably in the range of 15% by mass or more and 40% by mass or less.

[0087] The polymerization initiator is, for example, a benzophenone-based, acetophenone-based, benzoin ether-based, or thioxanthone-based polymerization initiator. The amount of the photopolymerization initiator is preferably in the range of 0.5 parts by mass to 10 parts by mass, more preferably in the range of 1% by mass to 5% by mass, relative to 100 parts by mass of the total amount of the (meth)acrylate and the acrylic acrylate.

[0088] The solvent is, for example, an organic solvent, such as acetone, toluene, xylene, ethanol, isopropyl alcohol, ethyl acetate, butyl acetate, methyl ethyl ketone, or a mixture thereof.

[0089] The proportion of the solvent in the curable resin composition is preferably in the range of 20% by mass to 80% by mass, and more preferably in the range of 40% by mass to 60% by mass.

[0090] The curable resin composition may further contain particles. By adding an appropriate amount of particles having an appropriate particle size to the curable resin composition, wrinkles can be uniformly formed on the surface of the surface protection layer 5.

[0091] Examples of the particles that can be used include particles made of organic materials such as polyethylene (PE) wax, polypropylene (PP) wax, and resin beads, and particles made of inorganic materials such as silica, glass, alumina, titania, zirconia, calcium carbonate, and barium sulfate.

[0092] The average particle size (D50) of the particles is preferably 10 μm or less, more preferably 1 μm or more and 8 μm or less, even more preferably 2 μm or more and 7 μm or less, and most preferably 3 μm or more and 6 μm or less. If the average particle size (D50) of the particles is large, the particles are more likely to fall off from the surface protective layer 5, which may make it difficult to achieve high scratch resistance. If the particles are small, the effect of generating wrinkles uniformly is reduced.

[0093] Here, "average particle size" or "average particle size (D50)" refers to the median size (D50) measured using a laser diffraction / scattering particle size distribution analyzer. When the curable resin composition contains particles, the surface protective layer 5 obtained from this coating liquid will also contain particles. The average particle size of the particles contained in the surface protective layer 5 can be determined by observing the cross section of the layer and averaging the particle sizes of multiple particles. The value obtained in this manner is substantially the same as the median size (D50) measured using a laser diffraction / scattering particle size distribution analyzer. Therefore, the above-mentioned range of average particle size can also be interpreted as the range of average particle sizes of the particles contained in the surface protective layer 5.

[0094] The amount of particles in the surface protective layer 5 is preferably in the range of 0.5 parts by mass or more and 10 parts by mass or less, more preferably in the range of 2 parts by mass or more and 8 parts by mass or less, and most preferably in the range of 2 parts by mass or more and 6 parts by mass or less, relative to 100 parts by mass of the cured resin.

[0095] When the amount of particles added is within the above range, the effect of generating wrinkles uniformly is particularly large. If the amount of particles added is too large, the particles are likely to fall off from the surface protective layer 5, which may make it difficult to achieve high scratch resistance.

[0096] The curable resin composition may further contain a light stabilizer. Examples of the light stabilizer that may be used include hindered amine light stabilizers. Examples of the hindered amine light stabilizer include bis(1,2,2,6,6-pentamethyl-4-piperidyl)[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methyl]butyl malonate (typical examples include those available from BASF under the trade name "Tinuvin 144"), BASF under the trade name "Tinuvin 123", and a reaction product of decanedioic acid bis(2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidinyl) ester (1,1-dimethylethyl hydroperoxide) and octane.

[0097] When a hindered amine light stabilizer is added to a curable resin composition, the proportion of the hindered amine light stabilizer in the curable resin composition is preferably in the range of 0.05% by mass to 5% by mass, more preferably in the range of 0.2% by mass to 3% by mass. A smaller proportion reduces the effect of improving stability against ultraviolet light. A larger proportion increases the likelihood of bleed-out. The surface protection layer 5 can be formed by irradiating light of 200 nm or less to cause curing and shrinkage near the surface, forming a fine uneven shape. In this case, a large proportion may inhibit curing near the surface.

[0098] The curable resin composition may further contain other additives such as an antibacterial agent, an antifungal agent, and an ultraviolet absorber. Examples of the ultraviolet absorber that can be used include benzotriazole-based, benzoate-based, benzophenone-based, and triazine-based ultraviolet absorbers.

[0099] The specular gloss GS(60°) of the surface protective layer 5 is preferably less than 15.0, more preferably 10 or less, and even more preferably 5 or less. The specular gloss GS(60°) of the surface protective layer 5 is, for example, 0.1 or more. Here, the "specular gloss GS(60°)" is the specular gloss measured at an incident angle of 60 degrees using a gloss meter conforming to ISO 2813. Note that the specular gloss GS(60°) is sometimes expressed by adding "%" after the numerical value, but the "%" will be omitted here.

[0100] <1.5> Primer Layer When an olefin-based resin is used as the material of the raw fabric layer 2, the surface of the raw fabric layer 2 is often in an inactive state. Therefore, in this case, it is preferable to provide a primer layer 6 between the raw fabric layer 2 and the substrate B. When the raw fabric layer 2 is made of an olefin-based material, the primer layer 6 may be omitted, and the raw fabric layer 2 may be subjected to a surface modification treatment such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, or dichromate treatment in order to improve the adhesion between the raw fabric layer 2 and the substrate B.

[0101] Materials that can be used for the primer layer 6 include, for example, the materials described above for the design layer 3. Since the primer layer 6 is applied to the back surface of the decorative sheet 1, and considering that the decorative sheet 1 will be wound up in web form, an inorganic filler may be added to the primer layer 6 to avoid blocking and increase adhesion to the adhesive. Examples of inorganic fillers include silica, alumina, magnesia, titanium oxide, and barium sulfate.

[0102] <2> Manufacturing Method of Decorative Sheet The decorative sheet 1 is manufactured, for example, by the following method. For the sake of brevity, explanations of the design layer 3, transparent resin layer 4, adhesive resin layer 4b, and primer layer 6 are omitted here.

[0103] First, a laminate is prepared that includes a raw fabric layer 2 and a pattern layer 3 provided thereon. Next, a coating film made of the curable resin composition as the surface protective layer coating liquid is formed on one side of this laminate, facing the raw fabric layer 2 with the pattern layer 3 sandwiched therebetween. This coating film can be formed by various printing methods, such as gravure printing, offset printing, screen printing, electrostatic printing, and inkjet printing, or various coating methods, such as roll coating, knife coating, microgravure coating, and die coating.

[0104] The coating film is then dried. Subsequently, a first irradiation step is carried out. In the first irradiation step, the coating film is irradiated with light having a wavelength of 200 nm or less (hereinafter referred to as first radiation). The curable resin composition has a large absorption coefficient for the first radiation. Therefore, the first radiation incident on the coating film can only reach a position several tens to several hundreds of nm away from the outermost surface. Therefore, in the first irradiation step, the crosslinking reaction proceeds in the surface region of the coating film, forming an extremely thin cured film, while the crosslinking reaction does not proceed in other regions, leaving the coating film uncured.

[0105] The coating film after the first irradiation step has wrinkles on its surface corresponding to the ridge portions 5 B. The present inventors believe that the reason why wrinkles are formed on the coating film surface by the first irradiation step is as follows.

[0106] As described above, the first radiation can only reach a position tens to hundreds of nanometers away from the outermost surface of the coating film. In other words, the crosslinking reaction of the ionizing radiation-curable resin occurs only on the surface of the coating film, and regions more than tens to hundreds of nanometers away from the outermost surface are uncured and contain highly fluid molecules. These highly fluid molecules swell the cured film, thereby increasing its volume. The increase in volume in the in-plane direction increases in-plane compressive stress, which then causes the cured film to buckle. In this way, wrinkles form on the surface of the coating film.

[0107] The first radiation can be extracted from excimer VUV light. Excimer VUV light can be generated from a lamp using a rare gas or a rare gas halide compound. When high-energy electrons are externally applied to a lamp filled with a rare gas or a rare gas halide compound, a large number of discharge plasmas (dielectric barrier discharges) are generated. This plasma discharge excites atoms of the discharge gas (rare gas), which momentarily transition to an excimer state. When returning from this excimer state to the ground state, light is emitted in a wavelength range specific to the excimer.

[0108] The gas used in the excimer lamp may be any conventional gas that emits light of 200 nm or less. Examples of suitable gases include rare gases such as Xe, Ar, and Kr, and mixtures of rare gases such as ArBr and ArF with halogen gases. The center wavelength of excimer lamps varies depending on the gas used, and may be, for example, approximately 172 nm (Xe), approximately 126 nm (Ar), approximately 146 nm (Kr), approximately 165 nm (ArBr), or approximately 193 nm (ArF).

[0109] Considering the magnitude of photon energy and the difference between wavelength and bond energy of organic matter, it is preferable to use a xenon lamp that emits excimer light with a central wavelength of 172 nm as the light source. Also, considering the cost of maintaining the equipment and the availability of materials, it is preferable to use a xenon lamp as the light source.

[0110] The first irradiation step is carried out in an atmosphere with a low oxygen concentration. Oxygen has a high absorption coefficient for light of 200 nm or less. Therefore, the first irradiation step is preferably carried out in, for example, a nitrogen gas atmosphere. The oxygen concentration in the gas phase in the first irradiation step, i.e., the residual oxygen concentration in the reaction atmosphere, is preferably 2000 ppm or less, and more preferably 1000 ppm or less.

[0111] Furthermore, oxygen in the atmosphere inhibits radical polymerization. Therefore, the residual oxygen concentration in the reaction atmosphere affects the formation of wrinkles on the coating surface. Therefore, changing the residual oxygen concentration in the reaction atmosphere can also change the surface properties of the surface protective layer 5.

[0112] The integrated light amount of the first radiation is 0.5 mJ / cm ２ More than 200mJ / cm ２ It is preferable that the dose is 1 mJ / cm or less. ２ More than 100mJ / cm ２ More preferably, it is 3 mJ / cm or less. ２ More than 50mJ / cm ２ More preferably, it is 5 mJ / cm or less. ２ 30mJ / cm or more ２ It is most preferable to set the integrated light dose as follows: If the integrated light dose is small, the expansion of the cured film in the in-plane direction will be small; if the integrated light dose is large, the surface condition of the coating film will deteriorate.

[0113] After the first irradiation step is completed, the second irradiation step is carried out. In the second irradiation step, the coating film is irradiated with a second radiation to cure the entire coating film. In this way, the surface protective layer 5 is obtained.

[0114] The second radiation is ionizing radiation such as an electron beam, or ultraviolet radiation having a longer wavelength than the first radiation. When ultraviolet radiation is used as the second radiation, the ultraviolet radiation has a wavelength at which the ionizing radiation curable resin exhibits a small absorption coefficient.

[0115] The cumulative amount of the second radiation is 10 mJ / cm ２ More than 500mJ / cm ２ It is preferable that the dose is 50 mJ / cm or less. ２ More than 400mJ / cm ２ More preferably, it is 100 mJ / cm or less. ２ More than 300mJ / cm ２ It is more preferable that:

[0116] <3> Effects The curable resin composition contains a (meth)acrylate having a smaller weight-average molecular weight and an acrylic acrylate having a larger weight-average molecular weight.

[0117] The (meth)acrylate used herein has a smaller weight-average molecular weight than acrylic acrylate. Therefore, a curable resin composition containing this (meth)acrylate can achieve a high crosslink density in the cured product. A surface protective layer made of a cured product with a high crosslink density has excellent scratch resistance.

[0118] However, when a surface protective layer is formed using only a (meth)acrylate having a small weight-average molecular weight, the adhesion of the surface protective layer to the base may be insufficient. Furthermore, when a surface protective layer is formed using only a low-molecular-weight compound having a large number of functional groups as the (meth)acrylate, for example, a (meth)acrylate monomer having a large number of functional groups, even if a surface protective layer having excellent scratch resistance and adhesion is obtained, the surface of such a surface protective layer may include an area where no uneven structure is formed.

[0119] Acrylic acrylate has a structure in which a (meth)acryloyl group is added to the side chain of an acrylic resin. The acrylic acrylate used here has a larger weight-average molecular weight than (meth)acrylate. Therefore, a cured product of a resin composition containing this acrylic acrylate contains a portion with a large molecular weight between crosslinks. As a result, this cured product exhibits reduced cure shrinkage and excellent flexibility. Therefore, a surface protective layer made of a cured product of a resin composition containing this acrylic acrylate generates little internal stress during curing, and can fill the interior of fine recesses present on the surface of the base without any gaps, thereby exhibiting excellent adhesion to the base.

[0120] The acrylic acrylate used here can impart flexibility to the cured film formed on the surface of the coating film in the first irradiation step. Therefore, even when a low-molecular-weight compound with a large number of functional groups is used as the (meth)acrylate, the in-plane expansion of the cured film and the resulting deformation of the cured film are not hindered in the first irradiation step, and an uneven structure can be formed on the entire surface of the surface protection layer.

[0121] Therefore, when the surface protective layer is formed using the above-mentioned curable resin composition, a laminated film having low gloss and excellent scratch resistance and adhesion of the surface protective layer can be realized.

[0122] Examples of the present invention will be described below. Note that the "particle size" described below is the above-mentioned "average particle size (D50)".

[0123] Example 1 The decorative sheet 1 described with reference to Figures 1, 3, and 4 was produced by the following method. First, a 55 μm thick olefin film (manufactured by Riken Technos Corporation) was prepared as the base fabric layer 2. One side of the base fabric layer 2 was subjected to a corona treatment, and then a pattern was printed on this side to form the design layer 3. The design layer 3 was formed using an ink obtained by adding 0.5 parts by mass of a hindered amine light stabilizer (Chimasorb (registered trademark) 944; manufactured by BASF) to a two-component urethane ink (V180; manufactured by Toyo Ink Co., Ltd.) per 100 parts by mass of the binder resin of the ink.

[0124] Next, a primer layer 6 was formed on the back surface of the raw fabric layer 2. The primer layer 6 was formed by printing with the same two-component urethane ink as that used to form the design layer 3.

[0125] Next, a curable resin composition was applied as a coating liquid for a surface protective layer onto the design layer 3. The coating liquid for a surface protective layer was applied so that the thickness of the coating film after drying would be 5 μm. The coating liquid for the surface protective layer was a mixture of the following ionizing radiation curable resin and the following additives (particles, photopolymerization initiator).

[0126] Ionizing radiation curable resin Resin A (acrylic acrylate) (average molecular weight of main chain: approximately 25,000, double bond equivalent: approximately 4,000) Blend: 75 parts by mass Resin X (acrylate monomer, molecular weight 550, number of functional groups: 6) Blend: 25 parts by mass Particles Product name: Sylysia 250N (manufactured by Fuji Silysia Chemical Ltd.) Particle size: 5 μm Blend: 5 parts by mass Photopolymerization initiator Product name: Omnirad 184 (manufactured by IGM Resins) Blend: 3 parts by mass.

[0127] Thereafter, the coating film made of the coating liquid for the surface protective layer was dried, and then the first irradiation step was carried out. Specifically, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film using a Xe excimer lamp at an integrated light intensity of 30 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm. ２ This caused wrinkles to form on the surface of the coating film.

[0128] Subsequently, a second irradiation step was carried out. Specifically, the coating film was irradiated with 200 mJ / cm using a high-pressure mercury lamp. ２ The entire surface was cured by irradiating it with ultraviolet light so that the surface protective layer 5 was formed.

[0129] In this manner, a decorative sheet 1 was obtained.

[0130] <Example 2> Decorative sheet 1 described with reference to Figures 1, 3 and 4 was produced in the same manner as in Example 1, except that the blending amount of Resin A in the ionizing radiation curable resin was 50 parts by mass and the blending amount of Resin X in the ionizing radiation curable resin was 50 parts by mass.

[0131] <Example 3> Decorative sheet 1 described with reference to Figures 1, 3 and 4 was produced in the same manner as in Example 1, except that the blending amount of Resin A in the ionizing radiation curable resin was 35 parts by mass and the blending amount of Resin X was 65 parts by mass.

[0132] <Example 4> Decorative sheet 1 described with reference to Figures 1, 3 and 4 was produced in the same manner as in Example 1, except that the blending amount of Resin A in the ionizing radiation curable resin was 25 parts by mass and the blending amount of Resin X in the ionizing radiation curable resin was 75 parts by mass.

[0133] <Example 5> Decorative sheet 1 described with reference to Figures 1, 3 and 4 was produced in the same manner as in Example 1, except that the blending amount of Resin A in the ionizing radiation curable resin was 15 parts by mass and the blending amount of Resin X was 85 parts by mass.

[0134] <Example 6> Decorative sheet 1 described with reference to Figures 1, 3 and 4 was produced in the same manner as in Example 1, except that the blending amount of Resin A in the ionizing radiation curable resin was 7.5 parts by mass and the blending amount of Resin X was 92.5 parts by mass.

[0135] <Example 7> Decorative sheet 1 described with reference to Figures 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin A (acrylic acrylate) (average molecular weight of main chain: approximately 25,000, double bond equivalent: approximately 4,000) Blended: 25 parts by mass Resin Y (acrylate monomer, molecular weight: 300, number of functional groups: 2) Blended: 75 parts by mass

[0136] 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin B (acrylic acrylate) (average molecular weight of main chain: approximately 25,000, double bond equivalent: approximately 2,000) Blended: 65 parts by mass Resin Y (acrylate monomer, molecular weight: 300, number of functional groups: 2) Blended: 35 parts by mass

[0137] 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin C (acrylic acrylate) (average molecular weight of main chain: approximately 75,000, double bond equivalent: approximately 1,100) Blended: 65 parts by mass Resin Y (acrylate monomer, molecular weight: 300, number of functional groups: 2) Blended: 35 parts by mass

[0138] 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin D (acrylic acrylate) (average molecular weight of main chain: approximately 150,000, double bond equivalent: approximately 5,000) Blended: 65 parts by mass Resin Y (acrylate monomer, molecular weight: 300, number of functional groups: 2) Blended: 35 parts by mass

[0139] 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin E (acrylic acrylate) (average molecular weight of main chain: approximately 700, double bond equivalent: approximately 500) Blended: 65 parts by mass Resin Y (acrylate monomer, molecular weight: 300, number of functional groups: 2) Blended: 35 parts by mass

[0140] <Example 12> Decorative sheet 1 described with reference to Figures 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin A (acrylic acrylate) (average molecular weight of main chain: approximately 25,000, double bond equivalent: approximately 4,000) Blended: 35 parts by mass Resin V (acrylate monomer mixture, molecular weight 150-300, number of functional groups 1-2) Blended: 65 parts by mass.

[0141] <Example 13> Decorative sheet 1, as explained with reference to Figures 1, 3, and 4, was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin A (acrylic acrylate) (average molecular weight of main chain: approximately 25,000, double bond equivalent: approximately 4,000) Blend: 15 parts by mass Resin V / X (acrylate monomer mixture, molecular weight 150-550, number of functional groups 1-6) Blend: 85 parts by mass Note that Resin V / X is a mixture of Resin V and Resin X.

[0142] <Example 14> Decorative sheet 1 described with reference to Figures 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin C (acrylic acrylate) (average molecular weight of main chain: approximately 75,000, double bond equivalent: approximately 1,100) Blended: 35 parts by mass Resin V (acrylate monomer mixture, molecular weight 150-300, number of functional groups 1-2) Blended: 65 parts by mass.

[0143] 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin C (acrylic acrylate) (average molecular weight of main chain: approximately 75,000, double bond equivalent: approximately 1,100) Blend: 15 parts by mass Resin V / X (acrylate monomer mixture, molecular weight 150-550, number of functional groups 1-6) Blend: 85 parts by mass.

[0144] 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin A (acrylic acrylate) (average molecular weight of main chain: approximately 25,000, double bond equivalent: approximately 4,000) Blend: 15 parts by mass Resin U / V (acrylate monomer / oligomer mixture, molecular weight 150-3,500, number of functional groups 1-10) Blend: 85 parts by mass.

[0145] Resin U / V is a mixture of resin U and resin V. Resin U is an acrylate oligomer having an average molecular weight of the main chain of about 3,500 and 10 functional groups.

[0146] Comparative Example 1 A decorative sheet similar to that described with reference to Figures 1, 3 and 4 was produced in the same manner as in Example 1, except that the blending amount of Resin A in the ionizing radiation curable resin was 100 parts by mass and the blending amount of Resin X was 0 parts by mass.

[0147] Comparative Example 2 A decorative sheet similar to that described with reference to Figures 1, 3 and 4 was produced in the same manner as in Example 1, except that the blending amount of Resin A in the ionizing radiation curable resin was 0 parts by mass and the blending amount of Resin X was 100 parts by mass.

[0148] Comparative Example 3 A decorative sheet similar to that described with reference to Figures 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin X / Y (acrylate monomer mixture, molecular weight 300 to 550, number of functional groups 2 to 6) Blend: 100 parts by mass Note that resin X / Y is a mixture of resin X and resin Y.

[0149] Comparative Example 4 A decorative sheet similar to that described with reference to Figures 1, 3, and 4 was produced in the same manner as in Example 1, except that the composition of the ionizing radiation curable resin was changed as follows: Ionizing radiation curable resin Resin Y / Z (acrylate monomer mixture, molecular weight 300 to 1000, number of functional groups 2 to 3) Blend: 100 parts by mass Resin Y / Z is a mixture of resin Y and resin Z. Resin Z is an acrylate monomer whose main chain has an average molecular weight of approximately 1000 and has three functional groups.

[0150] <Evaluation> Each of the decorative sheets described above was evaluated as follows: Those rated "AAA", "AA" or "A" were deemed to pass, as they presented no problems in actual use.

[0151] (1) Adhesion The adhesion of the surface protective layer to the substrate was evaluated by a cross-cut test specified in JIS K5400 (discontinued). Here, cuts with a depth greater than the thickness of the surface protective layer were formed in a grid pattern at 1 mm intervals on the surface of the decorative sheet. This resulted in 100 squares arranged in a grid pattern. Next, adhesive tape was applied to the surface of the decorative sheet, and the adhesive tape was then peeled off from the decorative sheet. The number of squares remaining on the decorative sheet was counted, and this number was used to evaluate adhesion based on the following criteria:

[0152] AA: The number of remaining squares was 95 or more. A: The number of remaining squares was within the range of 90 to 94. B: The number of remaining squares was 89 or less.

[0153] (2) Shaping state The surface protection layer was observed under a microscope to evaluate the formation state of the uneven structure, i.e., the shaping state. AA: The uneven structure was formed uniformly. A: The uneven structure was formed unevenly over the entire surface, although it was not uniform. B: The uneven structure was formed only in a part of the surface, and the other parts were in a high-gloss state.

[0154] (3) Gloss The specular gloss GS (60 °) of the decorative sheet was measured using a Rhopoint IQ (manufactured by Konica Minolta). The specular gloss GS (60 °) was measured before the start of the weather resistance test described below, and at 96 hours, 192 hours, and 240 hours after the start of the weather resistance test. The "60 degree gloss value" in the table below represents this specular gloss GS (60 °).

[0155] (Weather resistance test (metal weather)) In the weather resistance test, (1) light mode (illuminance 65 W / cm ２ (1) 20-hour black panel (black panel temperature 53°C, humidity 50%), (2) 30-second shower, (3) wet mode (black panel temperature 30°C, humidity 98%, 4 hours), and (4) 30-second shower were repeated in this order.

[0156] (4) Change in gloss: The difference Δ between the specular gloss GS (60°) 240 hours after the start of the weather resistance test and the specular gloss GS (60°) before the start of the weather resistance test ２４０ｈ－０ｈ The difference was calculated, and the gloss change was evaluated based on the following criteria: AA: The difference was less than 1.5. A: The difference was in the range of 1.5 to 1.9. B: The difference was 2.0 or more.

[0157] (5) Surface Condition The surface protective layer was observed with a microscope and a laser microscope before the start of the weather resistance test and 240 hours after the start of the weather resistance test. The surface condition was evaluated based on the observation results using the following criteria: AAA: No change in surface condition was observed before and after the weather resistance test. AA: A slight change in surface condition was observed after the weather resistance test compared to before the weather resistance test. A: A clear change in surface condition was observed after the weather resistance test compared to before the weather resistance test. B: A significant difference in surface condition was observed after the weather resistance test compared to before the weather resistance test, and it was possible to observe that the surface protective layer had been removed from the surface.

[0158] (6) Scratch Resistance Each decorative sheet was attached to wood substrate B using a urethane adhesive. A steel wool rubbing test was then conducted to evaluate scratch resistance. Specifically, the decorative sheet was rubbed back and forth 20 times with steel wool while applying a load of 100 g, and scratches and changes in gloss on the surface of the decorative sheet were visually confirmed.

[0159] The evaluation criteria were as follows: AAA: No scratches or changes in gloss occurred on the surface. AA: Minor scratches or changes in gloss occurred on a part of the surface. A: Minor scratches or changes in gloss occurred on the surface. B: Significant scratches or changes in gloss occurred on the surface.

[0160] Tables 1 and 2 show an outline of the composition of the curable resin composition. Tables 3 and 4 show the evaluation results. In Tables 3 and 4, the time in the column labeled "60-degree gloss value" indicates the time elapsed since the start of the weather resistance test. In Comparative Example 2, the evaluation of the shaping state was "B," and the specular gloss GS (60°) before the weather resistance test was extremely high, so evaluation of gloss change and surface state was not performed.

[0161]

[0162]

[0163]

[0164]

[0165] As shown in Tables 3 and 4, the decorative sheets according to Examples 1 to 16 exhibited sufficient performance in all of adhesion, shaping state, initial gloss, gloss change, surface condition, and scratch resistance. In contrast, the decorative sheet according to Comparative Example 1 exhibited sufficient performance in adhesion, shaping state, initial gloss, gloss change, and surface condition, but insufficient performance in scratch resistance. Furthermore, the decorative sheet according to Comparative Example 2 exhibited sufficient performance in adhesion and scratch resistance, but insufficient performance in shaping state and initial gloss. Furthermore, the decorative sheets according to Comparative Examples 3 and 4 exhibited sufficient performance in shaping state and initial gloss, but insufficient performance in adhesion, gloss change, surface condition, and scratch resistance.

[0166] 1...decorative sheet, 2...raw fabric layer, 3...pattern layer, 4...transparent resin layer, 4a...embossed pattern, 4b...adhesive resin layer, 5...surface protective layer, 5A...core portion, 5B...ridge portion, 11...decorative material, B...base material.

Claims

1. A curable resin composition comprising a (meth)acrylate, an acrylic acrylate as an adhesion aid, a photopolymerization initiator, and a solvent, wherein the weight average molecular weight of the acrylic acrylate is greater than the weight average molecular weight of the (meth)acrylate.

2. The curable resin composition according to claim 1, wherein the weight average molecular weight of the (meth)acrylate is in the range of 100 or more and 5,000 or less, and the weight average molecular weight of the acrylic acrylate is in the range of 500 or more and 150,000 or less.

3. A curable resin composition according to claim 1 or 2, wherein the proportion of the adhesion assistant in the total of the (meth)acrylate and the adhesion assistant is in the range of 5 mass % or more and 90 mass % or less.

4. A curable resin composition according to any one of claims 1 to 3, wherein the number of functional groups of the (meth)acrylate is in the range of 1 or more and 18 or less.

5. A curable resin composition according to any one of claims 1 to 4, wherein the double bond equivalent of the acrylic acrylate is in the range of 200 or more and 15,000 or less.

6. The curable resin composition according to any one of claims 1 to 5, wherein the (meth)acrylate comprises a (meth)acrylate monomer.

7. The curable resin composition according to any one of claims 1 to 6, wherein the (meth)acrylate contains an oligomer having 10 or less functionalities.

8. A curable resin composition described in any one of claims 1 to 7, comprising the photopolymerization initiator in an amount within the range of 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the total amount of the (meth)acrylate and the acrylic acrylate.

9. The curable resin composition according to any one of claims 1 to 8, further comprising a light stabilizer.

10. The curable resin composition according to any one of claims 1 to 9, further comprising particles having an average particle size of 10 µm or less.

11. The curable resin composition according to claim 10, comprising the particles in an amount of 0.5 parts by mass or more and 10 parts by mass or less per 100 parts by mass of the total amount of the (meth)acrylate and the acrylic acrylate.

12. A laminate film comprising a base film and a surface protective layer provided on the base film, the surface protective layer being made of a cured product of the curable resin composition according to any one of claims 1 to 11.

13. The laminate film according to claim 12, wherein the thickness of the surface protective layer is within the range of 2 μm or more and 20 μm or less.

14. The laminate film according to claim 12 or 13, wherein the specular gloss GS(60°) of the surface protective layer is less than 15.

0.

15. The laminated film according to any one of claims 12 to 14, wherein the surface of the surface protective layer is provided with an uneven structure including a plurality of ridge-like portions each protruding in the form of a ridge.

16. A laminate film as described in claim 15, wherein at least a portion of the plurality of ridge portions are adjacent to each other in the width direction, and in a cross section parallel to the width direction and the thickness direction of the surface protective layer at a position where the at least a portion of the plurality of ridge portions are adjacent to each other in the width direction, the portion where the uneven structure is provided has a sine wave shape.

17. A decorative material comprising the laminate film according to claim 12 and a substrate to which the laminate film is attached.

18. A method for producing a laminated film, comprising: applying the curable resin composition according to any one of claims 1 to 11 onto a substrate film to form a coating film; irradiating the coating film with light having a wavelength of 200 nm or less; and thereafter irradiating the coating film with ionizing radiation or ultraviolet light having a longer wavelength than the light.

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