Decorative sheet

Abstract

Provided is a decorative sheet having excellent scratch resistance and excellent adhesion between gloss adjustment layers. A decorative sheet (1) is provided with a raw material layer (2) and a surface protection layer, and the surface protection layer includes: a first gloss adjustment layer (5) that is provided on the raw material layer (2) and that contains, as a cured resin product, only a cured product of a first ionizing radiation-curable resin that is a first mixture of an acrylic acid ester and a methacrylic acid ester, and a second gloss adjustment layer (6) that is provided on the first gloss adjustment layer (5) and that contains, as a cured resin product, a cured product of a second ionizing radiation-curable resin that is a second mixture of an acrylic acid ester and a methacrylic acid ester; and a second gloss adjustment layer (6) that partially covers the upper surface of the first gloss adjustment layer (5), contains only a cured product of a second ionizing radiation-curable resin as a resin cured product, and has a specular gloss GS (60 DEG) lower than that of the first gloss adjustment layer (5).

Description

Technical Field

[0001] This invention relates to decorative sheets. Background Technology

[0002] Decorative materials used for interior and exterior decoration of buildings, doors and windows, and furniture are typically decorative panels made by attaching decorative sheets to the surface of a substrate using adhesives. Commonly, desired patterns such as wood grain or stone grain are applied to the decorative sheets. In addition, decorative sheets that not only simply display wood grain or stone grain patterns on a flat surface but also exhibit a textured, three-dimensional feel similar to natural wood or stone surfaces are widely used for applications requiring a high-end feel.

[0003] Various methods have been designed to create a three-dimensional effect on the surface of decorative panels, alongside flat patterns and designs, and are used according to their intended purpose. For example, one method involves creating a visual effect by using optical illusions, rather than actually forming depressions or convexities on the surface of the decorative material, by making the gloss levels of areas that should appear as depressions or convexities different from those of other areas. According to this method, even if no actual depressions or convexities are perceptible to the observer, the observer can still perceive areas with relatively high gloss levels as convex and areas with relatively low gloss levels as concave.

[0004] To manufacture such a decorative sheet, for example, a printed layer containing a pattern corresponding to the recessed area is first formed on one surface of a substrate. Next, a first gloss adjustment layer with low gloss, transparent or translucent, is formed on the entire surface of the substrate where the printed layer is formed. Then, a second gloss adjustment layer with high gloss, transparent or translucent, is formed in all areas of the first gloss adjustment layer except for the area corresponding to the pattern. It should be noted that if the gloss ratio of the first and second gloss adjustment layers is reversed, a decorative sheet with an inverted relief relationship can be obtained.

[0005] Using this method, only two coatings with different gloss levels are needed, and no special agents are required for any substrate to achieve a three-dimensional, textured effect. Furthermore, the gloss adjustment layers with different gloss levels can be formed after the pattern (pattern ink layer) is formed using conventional printing methods such as gravure printing. Therefore, no special equipment is required, production efficiency is high, and alignment of the second gloss adjustment layer with the pattern is easy. Additionally, since the second gloss adjustment layer can be quite thin compared to the perceived unevenness, it not only reduces resin usage but also offers advantages in flexibility, making it easy to produce decorative sheets with excellent bending adaptability. Moreover, since the surface of the decorative sheet does not have significant unevenness, contaminants do not remain in the recesses.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: International Publication No. 2022 / 182259

[0009] Patent Document 2: Japanese Patent Application Publication No. 2014-188842 Summary of the Invention

[0010] The purpose of this invention is to provide a decorative sheet with excellent scratch resistance and adhesion between gloss adjustment layers.

[0011] According to one aspect of the present invention, a decorative sheet is provided having a base material layer and a surface protective layer, the surface protective layer comprising: a first gloss adjusting layer disposed on the base material layer, comprising only a cured product of a first ionizing radiation-curable resin as a resin cured product, the first ionizing radiation-curable resin being a first mixture of acrylate and methacrylate; and a second gloss adjusting layer partially covering the top of the first gloss adjusting layer, comprising only a cured product of a second ionizing radiation-curable resin as a resin cured product, having a lower specular gloss GS (60°) compared to the first gloss adjusting layer.

[0012] According to other aspects of the invention, a decorative sheet relating to the above aspects is provided, wherein, in the first ionizing radiation-curable resin, the molar number of methacrylamide groups accounts for a proportion of the total molar number of acryloylamide groups and the total molar number of methacrylamide groups in the range of 3% to 50%.

[0013] According to yet another aspect of the invention, a decorative sheet is provided that relates to any of the above aspects, wherein the methacrylate is a monofunctional, difunctional, or trifunctional methacrylate.

[0014] According to yet another aspect of the invention, a decorative sheet relating to any of the above aspects is provided, wherein the second ionizing radiation-curable resin is an acrylate, or a second mixture of an acrylate and a methacrylate, wherein the molar number of methacryloyl groups in the second mixture is smaller in proportion to the total molar number of acryloyl groups and the total molar number of methacryloyl groups compared to the first mixture.

[0015] According to yet another aspect of the invention, a decorative sheet is provided that relates to any of the above aspects, wherein the second ionizing radiation-curable resin comprises an acrylate with two or more functions containing repeating structures.

[0016] According to another aspect of the present invention, a decorative sheet relating to the above aspects is provided, wherein the repeating structure is repeated three times or more.

[0017] According to another aspect of the invention, a decorative sheet is provided that relates to any of the above aspects, wherein the surface of the second gloss adjustment layer is provided with a concave-convex structure comprising a plurality of ridges each protruding in a ridge-like manner.

[0018] According to another aspect of the invention, a decorative sheet relating to the above aspects is provided, wherein the ratio of the average length RSm of the roughness curve element of the uneven structure to the arithmetic mean roughness Ra, RSm / Ra, is in the range of 10 to 900, preferably in the range of 10 to 500.

[0019] According to another aspect of the invention, a decorative sheet relating to any of the above aspects is provided, wherein the thickness of each of the first gloss adjustment layer and the second gloss adjustment layer is in the range of 2 μm to 20 μm.

[0020] According to yet another aspect of the invention, a decorative sheet relating to any of the above aspects is provided, wherein the second gloss adjustment layer further comprises particles with an average particle size of less than 10 μm.

[0021] According to another aspect of the invention, a decorative sheet relating to the above aspects is provided, wherein, when the mass of the second ionizing radiation-curable resin is set to 100 parts by mass, the mass of the particles is in the range of 0.5 parts by mass to 20 parts by mass.

[0022] According to another aspect of the present invention, a decorative sheet relating to any of the above aspects is provided, wherein the specular gloss GS (60°) of the first gloss adjustment layer is 3 or more, and the specular gloss GS (60°) of the second gloss adjustment layer is 20 or less, preferably 10 or less.

[0023] According to another aspect of the invention, a decorative sheet is provided that relates to any of the above aspects, wherein the difference between the specular gloss GS (60°) of the first gloss adjustment layer and the specular gloss GS (60°) of the second gloss adjustment layer is 1 or more.

[0024] According to another aspect of the present invention, a decorative material is provided, comprising: a decorative sheet according to any of the above aspects, and a substrate on which the decorative sheet is adhered.

[0025] According to another aspect of the present invention, a method for manufacturing a decorative sheet is provided, comprising: forming a first coating film on a raw material layer, wherein the first coating film comprises only a first ionizing radiation-curable resin as a resin, said first ionizing radiation-curable resin being a first mixture of acrylate and methacrylate; performing a first irradiation step of irradiating the first coating film with ionizing radiation or ultraviolet light to semi-cur the first coating film; forming a second coating film on the semi-cured first coating film in such a way as to partially cover the upper surface of the first coating film, wherein said second coating film comprises only a second ionizing radiation-curable resin as a resin; and irradiating the first coating film and the second coating film with ionizing radiation or ultraviolet light to fully cure the first coating film and the second coating film.

[0026] According to another aspect of the present invention, a method for manufacturing a decorative sheet according to the above-mentioned aspect is provided, wherein the complete curing of the first coating and the second coating comprises: a second irradiation step of irradiating the second coating with light having a wavelength of less than 200 nm; and then, a third irradiation step of irradiating the first coating and the second coating with ionizing radiation or with ultraviolet light having a wavelength longer than that of the light irradiated in the second irradiation step.

[0027] According to the present invention, a decorative sheet with excellent adhesion between scratch-resistant and gloss-adjusting layers is provided. Attached Figure Description

[0028] [ Figure 1 ] Figure 1 This is a cross-sectional view of a decorative material comprising a decorative sheet according to one embodiment of the present invention.

[0029] [ Figure 2 ] Figure 2 yes Figure 1 A cross-sectional view of the second gloss adjustment layer contained in the decorative piece.

[0030] [ Figure 3 ] Figure 3 This is a microscope image of a second gloss adjustment layer contained in a decorative sheet, which is an example of the present invention.

[0031] [ Figure 4 ] Figure 4It is magnification Figure 2 A cross-sectional view shown as a portion of the second gloss adjustment layer. Detailed Implementation

[0032] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments described below are more specific embodiments of any of the above aspects. The matters described below may be incorporated into the above aspects individually or in combination.

[0033] Furthermore, the embodiments shown below illustrate configurations for embodying the technical concept of the present invention. The technical concept of the present invention is not limited by the material, shape, or structure of the constituent components described below. Various modifications can be made to the technical concept of the present invention within the scope defined by the claims.

[0034] It should be noted that for elements with the same or similar functions, the same reference numerals will be used in the accompanying drawings below, and repeated descriptions will be omitted. Furthermore, the drawings are schematic, and the relationship between dimensions in one direction and dimensions in other directions, as well as the relationship between the dimensions of one component and the dimensions of other components, may differ from the actual situation.

[0035] <1> Decorative materials and decorative panels

[0036] Figure 1 This is a cross-sectional view of a decorative material comprising a decorative sheet according to one embodiment of the present invention. Figure 2 yes Figure 1 A cross-sectional view of the second gloss adjustment layer contained in the decorative piece. Figure 3 This is a micrograph of the second gloss adjustment layer contained in a decorative sheet, which is an example of the present invention. Figure 4 It is magnification Figure 2 A cross-sectional view shown as a portion of the second gloss adjustment layer.

[0037] It should be noted that, Figure 2 and Figure 4 The cross-section shown is along the thickness direction of the second gloss adjustment layer. Additionally, Figure 3 The microscope images are planar images obtained using a laser microscope (Olympus Corporation OLS-4000).

[0038] Figure 1 The decorative material 11 shown includes a substrate B and a decorative sheet 1 adhered thereto. Here, the decorative material 11 is a decorative panel. The decorative panel can be flat, curved, or folded. The decorative material 11 can also have shapes other than a panel.

[0039] Here, substrate B is a board material. The board material can be, for example, wood-based panels, inorganic panels, metal panels, or composite panels made of multiple materials. Substrate B can also have shapes other than those of a board.

[0040] Decorative sheet 1 includes a base material layer 2, a solid ink layer 3, a pattern ink layer 4, a first gloss adjustment layer 5, and a second gloss adjustment layer 6. The solid ink layer 3, pattern ink layer 4, first gloss adjustment layer 5, and second gloss adjustment layer 6 are sequentially disposed on the side of the base material layer 2 opposite to the side facing the substrate B, starting from the base material layer 2 side. Alternatively, one or more other layers, such as a transparent resin layer, may be disposed between the pattern ink layer 4 and the first gloss adjustment layer 5. A primer layer may also be disposed on top of one or more of the base material layer 2, solid ink layer 3, and pattern ink layer 4. Furthermore, one or both of the solid ink layer 3 and pattern ink layer 4 may be omitted.

[0041] The elements contained in decorative piece 1 will be described in turn below.

[0042] <1.1> Raw Material Layer

[0043] As the raw material layer 2 or its material, the following can be used: paper types such as thin paper, resin-blended paper, titanium paper, resin-impregnated paper, flame-retardant paper, and inorganic paper; woven or nonwoven fabrics made of natural or synthetic fibers; synthetic resin-based substrates containing polyolefin resins such as homopolymer or atactic polypropylene resin and polyethylene resin, copolyester resin, amorphous crystalline polyester resin, polyethylene naphthalate resin, polybutene resin, acrylic resin, polyamide resin, polycarbonate resin, polyvinyl chloride resin, polyvinylidene chloride resin, fluoropolymer resin, etc.; wood-based substrates such as wood veneer, sliced ​​veneer, plywood, engineered wood, particleboard, and medium-density fiberboard; inorganic substrates such as gypsum board, cement board, calcium silicate board, and ceramic board; metal-based substrates made of metals such as iron, copper, aluminum, and stainless steel; or composites or laminates thereof. The raw material layer 2 can have various forms such as film, sheet, plate, and irregularly shaped bodies.

[0044] <1.2> Solid Ink Layer

[0045] The solid ink layer 3 is a continuous film formed by covering one surface of the base material layer 2 with ink. The solid ink layer 3 serves as a masking layer for the substrate B or the base material layer 2. Additionally, the solid ink layer 3 also functions as a planarization layer. The solid ink layer 3 can have a single-layer structure or a multi-layer structure.

[0046] The solid ink layer 3 can be formed, for example, using printing ink (or coating agent) that dissolves or disperses colorants such as matrix, dyes and pigments in a solvent.

[0047] As a matrix, various synthetic resins such as oily nitrocellulose resin, 2-component urethane resin, acrylic resin, styrene resin, polyester resin, urethane resin, polyethylene resin, alkyd resin, epoxy resin, melamine resin, fluororesin, silicone resin, and rubber resin can be used; or mixtures or copolymers thereof.

[0048] As colorants, inorganic pigments such as carbon black, titanium dioxide, zinc dioxide, carmine, chrome yellow, dark blue, and cadmium red can be used; organic pigments such as azo pigments, lake pigments, anthraquinone pigments, phthalocyanine pigments, isoindolinone pigments, and dioxazine pigments can be used; or mixtures thereof.

[0049] As solvents, toluene, xylene, ethyl acetate, butyl acetate, methanol, ethanol, isopropanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, water, or mixtures thereof can be used, for example.

[0050] In order to impart various functions, functional additives such as extender pigments, plasticizers, dispersants, surfactants, tackifiers, adhesives, driers, curing agents, curing accelerators, and curing delayers can also be added to the above inks.

[0051] <1.3> Pattern Ink Layer

[0052] The pattern ink layer 4 is provided for adding patterns and designs to the decorative piece 1. These patterns and designs can be, for example, wood grain, stone grain, sand grain, tile pattern, brickwork pattern, fabric pattern, leather pattern, or geometric shapes. Figure 1 In the example, the pattern ink layer 4 partially covers the printed pattern on top of the solid ink layer 3. This printed pattern is positioned directly below the second gloss adjustment layer. In other words, the second gloss adjustment layer 6 is positioned to coincide with the pattern ink layer 4. That is, the shape and position of the printed pattern contained in the pattern ink layer 4 and the pattern of the second gloss adjustment layer 6 as projected onto a plane perpendicular to the thickness direction are identical. It should be noted that, hereinafter, the state of identical shape and position as projected onto a plane perpendicular to the thickness direction is sometimes simply referred to as "identical shape and position."

[0053] The pattern ink layer 4 can be formed, for example, using the ink described with respect to the solid ink layer 3. The pattern ink layer 4 is formed using the number of printing plates required to represent the desired design. That is, the pattern ink layer 4 can be a layer consisting of a single printed pattern made of a single ink, or a layer consisting of multiple printed patterns made of different inks. In the latter case, one printed pattern may correspond to the shape and position of the pattern in the second gloss adjustment layer 6, or a combination of two or more printed patterns may correspond to the shape and position of the pattern in the second gloss adjustment layer 6. For example, one printed pattern or a combination of two or more printed patterns may correspond to the shape and position of the pattern in the second gloss adjustment layer 6, with the remaining printed patterns located in the area corresponding to the opening of the second gloss adjustment layer 6.

[0054] When only one printed pattern is contained in the pattern ink layer 4, the color of that printed pattern is different from that of the solid ink layer 3. When the pattern ink layer 4 contains multiple printed patterns, and the combination of these printed patterns corresponds to the shape and position of the pattern in the second gloss adjustment layer 6, the color of one or more of these printed patterns (e.g., all of these printed patterns) is different from that of the solid ink layer 3. When the pattern ink layer 4 contains multiple printed patterns, and one or more printed patterns correspond to the shape and position of the pattern in the second gloss adjustment layer 6, and the remaining printed patterns are located in the area corresponding to the opening of the second gloss adjustment layer 6, the color of one or more of the former's printed patterns is different from that of both the solid ink layer 3 and the latter's printed patterns. For example, the color of all the former's printed patterns is different from that of both the solid ink layer 3 and the latter's printed patterns.

[0055] Here, as an example, the pattern ink layer 4 is a layer consisting of a single printed pattern made of a single ink, and its color is different from that of the solid ink layer 3.

[0056] <1.4> Transparent Resin Layer

[0057] As described above, the decorative sheet 1 may also include a transparent resin layer between the pattern ink layer 4 and the first gloss adjustment layer 5. The transparent resin layer helps to improve the abrasion resistance of the decorative sheet 1.

[0058] The transparent resin layer is preferably made of a resin composition with an olefin-based resin as the main material. Examples of olefin-based resins include polypropylene, polyethylene, and polybutene. Olefin resins can also be polymers obtained by homopolymerization or copolymerization of α-olefins such as propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecanene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecanene, 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-dodecene, and 12-ethyl-1-tetradecene. Olefin-based resins can also be copolymers formed by copolymerizing ethylene or α-olefins with monomers other than those thereof, such as ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, ethylene-methyl methacrylate copolymers, ethylene-ethyl methacrylate copolymers, ethylene-butyl methacrylate copolymers, ethylene-methyl acrylate copolymers, ethylene-ethyl acrylate copolymers, and ethylene-butyl acrylate copolymers. In particular, highly crystalline polypropylene is preferred when further improvements in surface strength are desired.

[0059] Heat stabilizers, UV absorbers, light stabilizers, anti-blocking agents, catalyst trapping agents, colorants, and other additives can be added to the transparent resin layer. These additives can be appropriately selected and used from well-known additives. The transparent resin layer can be formed by various lamination methods such as hot pressing, extrusion lamination, and dry lamination.

[0060] <1.5> Primer layer

[0061] As described above, a primer layer can be applied over one or more of the base material layer 2, solid ink layer 3, and pattern ink layer 4.

[0062] When using an olefin-based resin as the material for the base layer 2, the surface of the base layer 2 is mostly inert. Therefore, in this case, it is preferable to provide a primer layer between the base layer 2 and the substrate B. When the base layer 2 is made of an olefin-based material, in order to omit the primer layer and improve the adhesion between the base layer 2 and the substrate B, the base layer 2 can also undergo surface modification treatments such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, or dichromate treatment.

[0063] Materials used as primer layers can include, for example, nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylics, polyesters, or their modified forms, used alone or in combination. They can be water-based, solvent-based, or emulsion-type, and can be a one-component or a two-component type using a curing agent. The primer layer can be formed by curing a layer of curable ink using irradiation with ultraviolet light or an electron beam. The most common method is to use urethane-based inks and cure them with isocyanates. In addition to binders, the inks used to form the primer layer may contain pigments, dyes, colorants, extender pigments, solvents, and various additives commonly found in inks. Examples of versatile pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolide, cobalt, phthalocyanine, carbon, titanium dioxide, iron oxide, mica, and pearl pigments.

[0064] Since the primer layer is applied to the back of the decorative sheet 1, when considering the case where the decorative sheet 1 is rolled up in a mesh, an inorganic filler can be added to the primer layer to avoid adhesion and improve the adhesion to the adhesive. Examples of inorganic fillers include silica, alumina, magnesium oxide, titanium oxide, and barium sulfate.

[0065] <1.6> First Gloss Adjustment Layer

[0066] The first gloss adjustment layer 5 is disposed on the original material layer 2. Here, the first gloss adjustment layer 5 covers the solid ink layer 3 and the pattern ink layer 4.

[0067] Compared to the second gloss adjustment layer 6, the first gloss adjustment layer 5 has a higher specular gloss GS (60°). The specular gloss GS (60°) of the first gloss adjustment layer 5 is preferably 3 or more, more preferably 5 or more, and even more preferably 7 or more. According to one example, the specular gloss GS (60°) of the first gloss adjustment layer 5 is 30 or less. Here, "spectral gloss GS (60°)" refers to the specular gloss measured using a gloss meter at an incident angle of 60 degrees according to ISO 2813. It should be noted that the specular gloss GS (60°) is sometimes indicated by adding "%" after the numerical value, but the "%" is omitted here.

[0068] The first gloss adjusting layer 5 is composed of a resin-cured product. The first gloss adjusting layer 5 may also contain particles. When the mass of the first gloss adjusting layer 5 is set to 100 parts by mass, the mass of the resin-cured product contained in the first gloss adjusting layer 5 is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more.

[0069] As a cured resin product, the first gloss adjustment layer 5 contains only the cured product of the first ionizing radiation-curable resin. Here, "ionizing radiation" refers to a beam of charged particles such as an electron beam. The first ionizing radiation-curable resin is cured by irradiation with ionizing radiation. Alternatively, the first ionizing radiation-curable resin can also be cured by irradiation with ultraviolet light.

[0070] As a first-ionizing-radiation-curing resin, various known resins such as monomers or commercially available oligomers can be used, for example, (meth)acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, or epoxy resins. The first-ionizing-radiation-curing resin can be either a water-based resin or a non-water-based (organic solvent-based) resin. The first-ionizing-radiation-curing resin can also be solvent-free.

[0071] The main components of the first ionizing radiation-curable resin are a first mixture of acrylate resin and methacrylate resin.

[0072] The methacrylate is preferably a monofunctional, difunctional, or trifunctional methacrylate. The methacrylate can be any one of a monofunctional, difunctional, or trifunctional methacrylate, or two or more of them.

[0073] When using methacrylates with a high number of functional groups, the degree of crosslinking and scratch resistance are improved compared to using methacrylates with a low number of functional groups. However, when using methacrylates with an excessive number of functional groups, the rate of crosslinking reaction caused by ionizing radiation or ultraviolet light irradiation increases, thus narrowing the process window that enables high adhesion between the first gloss adjustment layer 5 and the second gloss adjustment layer 6.

[0074] In the first ionizing radiation-curable resin, the proportion of the molar number of methacryloyl groups in the total molar number of acryloyl groups and the molar number of methacryloyl groups is preferably in the range of 3% to 50%, more preferably in the range of 5% to 40%.

[0075] Methacrylate can be semi-cured by irradiating a first coating containing a first ionizing radiation-curable resin with ionizing radiation or ultraviolet light. When the above ratio is increased, the process window for achieving high adhesion between the first gloss adjustment layer 5 and the second gloss adjustment layer 6 widens. However, when the above ratio is too high, the scratch resistance of the decorative sheet 1 decreases.

[0076] The thickness of the first gloss adjusting layer 5 is preferably set in the range of 2 μm to 20 μm, more preferably in the range of 3 μm to 20 μm, and even more preferably in the range of 5 μm to 15 μm. When the thickness of the first gloss adjusting layer 5 is reduced, the scratch resistance decreases. When the thickness of the first gloss adjusting layer 5 is increased, the processability of the decorative piece 1 decreases, and it is prone to whitening during bending processing.

[0077] <1.7> Second Gloss Adjustment Layer

[0078] The second gloss adjustment layer 6 partially covers the top of the first gloss adjustment layer 5. The second gloss adjustment layer 6 and the first gloss adjustment layer 5 together constitute a surface protective layer.

[0079] The second gloss adjustment layer 6 sandwiches the first gloss adjustment layer 5 in the middle and is opposite to the pattern ink layer 4. The second gloss adjustment layer 6 and the pattern ink layer 4 have the same shape and position.

[0080] It should be noted that, here, the second gloss adjustment layer 6 is completely identical in shape and position to the pattern ink layer 4, but other configurations are also possible. For example, the orthographic projection of the pattern ink layer 4 onto a plane perpendicular to the thickness direction can be at least partially spaced from the outline of the orthographic projection of the second gloss adjustment layer 6 onto the aforementioned plane, and located inside that outline.

[0081] Furthermore, here, the pattern ink layer 4 consists of a single printed pattern. However, when the pattern ink layer 4 consists of multiple printed patterns of different colors, the second gloss adjustment layer 6 can be aligned with the shape and position of the combination of these printed patterns. Alternatively, in this case, the second gloss adjustment layer 6 can be aligned with the shape and position of one or more of these printed patterns, with the remaining printed patterns positioned at locations not directly opposite the second gloss adjustment layer 6.

[0082] Preferably, at least 50%, more preferably at least 70%, and even more preferably at least 90% of the area of ​​the second gloss adjustment layer 6 projected onto a plane perpendicular to the thickness direction coincides with the projected area of ​​one or more printed patterns that are consistent with the shape and position of the second gloss adjustment layer 6 onto the aforementioned plane.

[0083] Compared to the first gloss adjustment layer 5, the specular gloss GS (60°) of the second gloss adjustment layer 6 is lower. The specular gloss GS (60°) of the second gloss adjustment layer 6 is preferably 20 or less, more preferably 10 or less. According to one example, the specular gloss GS (60°) of the second gloss adjustment layer 6 is 0.5 or more.

[0084] The difference between the specular gloss GS (60°) of the first gloss adjustment layer 5 and the specular gloss GS (60°) of the second gloss adjustment layer 6 is preferably 1 or more, more preferably 3 or more, and even more preferably 5 or more. According to one example, the difference is 20 or less.

[0085] An uneven structure is provided on the surface of the second gloss adjustment layer 6. The uneven structure provided on the second gloss adjustment layer 6 serves to make the specular gloss GS (60°) of the second gloss adjustment layer 6 lower than the specular gloss GS (60°) of the first gloss adjustment layer 5.

[0086] Here, the surface of the second gloss adjustment layer 6 is provided with a concave-convex structure comprising multiple ridge-shaped portions, each protruding in a ridge-like manner. That is, as shown... Figure 2 and Figure 4 As shown, the second gloss adjustment layer 6 includes: a thin layer, namely a core 6A, having a flat upper surface; and a plurality of ridges 6B each protruding in a ridge-like manner from the upper surface of the core 6A.

[0087] Here, in this disclosure, the ridge portion 6B refers, for example, to the portion from the lowest point to the highest point of the protrusion provided on the surface of the second gloss adjustment layer 6, and the core portion 6A refers to the portion of the second gloss adjustment layer 6 other than the ridge portion 6B. Furthermore, "ridged" refers to a convex shape extending in a line in a plan view.

[0088] The ridge 6B can be curved or straight in a plan view, but from the viewpoint of fingerprint resistance of the decorative piece 1, it is preferred. Figure 3 The example is a curved shape. It should be noted that, as described later, the second gloss adjustment layer 6 having the ridge portion 6B can be formed, for example, by irradiating the surface of the coating containing the second ionizing radiation-curable resin with light of a specific wavelength, causing the cured film generated on the surface of the coating to expand inward.

[0089] The ratio of the average length RSm of the roughness curve elements of the uneven structure on the upper surface of the second gloss adjustment layer 6 to the arithmetic mean roughness Ra, RSm / Ra, is preferably in the range of 10 to 900, more preferably in the range of 10 to 500, more preferably in the range of 10 to 400, and even more preferably in the range of 50 to 350. When the ratio RSm / Ra decreases, the spacing between the protrusions becomes smaller. As a result, it becomes difficult to wipe away dirt adhering to the surface of the decorative piece 1, and the stain resistance decreases. When the ratio RSm / Ra increases, the spacing between the protrusions becomes larger, and the effect of the uneven structure on reducing the specular gloss GS (60°) of the second gloss adjustment layer 6 becomes smaller.

[0090] The ratio RSm / Ra is preferably 80 or higher. As the ratio RSm / Ra increases, the spacing between the protrusions increases, and the affinity of water or detergent (water containing surfactants or alcohols) for the upper surface of the second gloss adjustment layer 6 increases. If the decorative sheet 1 has such surface properties in the second gloss adjustment layer 6, it is easy to wipe away dirt with water or detergent even if the surface is contaminated.

[0091] The ratio RSm / Ra is preferably 100 or higher. If the ratio RSm / Ra is within this range, it is possible to make contact between a commercially available cleaning sponge and the boundary of the protrusion on the upper surface of the second gloss adjustment layer 6 and the area theren. Therefore, even if the surface of the decorative piece 1 is contaminated, it is easy to wipe away dirt using a commercially available cleaning sponge.

[0092] Here, the arithmetic mean roughness Ra and the average length RSm of the roughness curve elements are measured values ​​when measured using a line roughness meter (according to JIS B0601:2013).

[0093] The arithmetic mean roughness Ra is preferably in the range of 0.2 μm to 10.0 μm, more preferably in the range of 0.5 μm to 5.0 μm, and even more preferably in the range of 0.8 μm to 4.0 μm.

[0094] The average length RSm of the roughness curve element is preferably in the range of 50 μm to 800 μm, more preferably in the range of 80 μm to 600 μm, and even more preferably in the range of 100 μm to 500 μm.

[0095] The upper surface of the second gloss adjustment layer 6 can also be sinusoidal in shape in a cross-section parallel to the thickness direction and the arrangement direction of the ridges 6B. Here, as... Figure 4 As shown, "sine wave shape" refers to the shape of a line that can be represented by a sine wave from the lowest position C of the ridge 6B to the highest position D (apex).

[0096] The thickness of the second gloss adjustment layer 6 is preferably set in the range of 2 μm to 20 μm, more preferably in the range of 3 μm to 20 μm, even more preferably in the range of 5 μm to 15 μm, and most preferably in the range of 5 μm to 12 μm. When the thickness of the second gloss adjustment layer 6 is small, it is difficult to achieve the above-mentioned surface properties by referring to the ratio RSm / Ra, etc., using the method described later. When the thickness of the second gloss adjustment layer 6 is increased, the processability of the decorative sheet 1 decreases, and it is prone to whitening during bending processing.

[0097] Here, the thickness of the second gloss adjusting layer 6 is the thickness of a layer with an apparent area and volume equal to that of the second gloss adjusting layer 6 and a flat surface. The thickness of the second gloss adjusting layer 6 is determined, for example, by the following method: First, a cross-section parallel to the thickness direction of the second gloss adjusting layer 6 and perpendicular to the length direction of the ridge portion 6B is photographed. Next, the dimensions of the second gloss adjusting layer 6 in the width direction of the ridge portion 6B and the area of ​​the cross-section of the second gloss adjusting layer 6 are determined based on the cross-sectional image. The thickness of the second gloss adjusting layer 6 is obtained by dividing this area by the aforementioned dimensions. It should be noted that when the coating liquid used for the second gloss adjusting layer, as described later, is solvent-free, the thickness of the coating film formed by this coating liquid is equal to the thickness of the second gloss adjusting layer 6.

[0098] Furthermore, the thickness of the second gloss adjustment layer 6 is preferably set such that the ratio of the thickness (or height) of the ridge portion 6B to the thickness of the core portion 6A (thickness of the ridge portion 6B / thickness of the core portion 6A) is in the range of 0.01 to 2.0, and more preferably in the range of 0.1 to 1.0.

[0099] The second gloss adjusting layer 6 contains a resin-cured product. As described later, the second gloss adjusting layer 6 may also contain particles. When the mass of the second gloss adjusting layer 6 is set to 100 parts by mass, the mass of the resin-cured product contained in the second gloss adjusting layer 6 is preferably 60 parts by mass or more, more preferably 70 parts by mass or more, and even more preferably 80 parts by mass or more.

[0100] The second gloss adjustment layer 6 contains only the cured product of the second ionizing radiation-curable resin as the resin curing product. As mentioned above, ionizing radiation is a beam of charged particles such as an electron beam. The second ionizing radiation-curable resin is cured by irradiation with ionizing radiation. Alternatively, the second ionizing radiation-curable resin can also be cured by irradiation with ultraviolet light. The second ionizing radiation-curable resin used here is cured by irradiation with light of wavelength below 200 nm, which has a high absorption coefficient.

[0101] As a second ionizing radiation curable resin, various known resins such as monomers or commercially available oligomers can be used, for example, (meth)acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, or epoxy resins. The second ionizing radiation curable resin can be either a water-based resin or a non-water-based (organic solvent-based) resin. The second ionizing radiation curable resin can also be solvent-free.

[0102] The main component of the second ionizing radiation curable resin is preferably acrylate. Here, "main component" means that it contains 60 parts by mass or more, more preferably 70 parts by mass or more, and most preferably 80 parts by mass or more, relative to 100 parts by mass of the constituent resin.

[0103] The acrylate is preferably a acrylate with 2 or more functional groups, more preferably a acrylate with 3 or more functional groups. In order to obtain a second gloss adjustment layer 6 with excellent scratch resistance, the acrylate is preferably 3 or more functional groups. There is no upper limit to the number of functional groups of the acrylate, but according to one example, it is 6 or less functional groups.

[0104] The acrylate preferably contains a repeating structure. This repeating structure is, for example, any one of an ethylene oxide (EO) structure, a propylene oxide (PO) structure, and an ε-caprolactone (CL) structure. The repeating structure is preferably ethylene oxide or propylene oxide. In the acrylate, the repeating structure may be located between an acryloyl group and a hydroxymethyl group in the ring-opening state.

[0105] The repetition number of the repeating structure is preferably 3 or more. When using an acrylate with a high repetition number, the cured film is prone to expand inward in the second irradiation step described later, thus easily generating wrinkles on the coating surface corresponding to the ridge 6B. However, as the repetition number increases, the crosslinking density decreases, and the scratch resistance of the surface protective layer decreases. Therefore, the repetition number is preferably 30 or less, more preferably 20 or less.

[0106] The number of repetitions of the above repeating structure can be analyzed using MALDI-TOF-MS. Ionizing radiation-cured resins sometimes exhibit molecular weight distributions. In the case of molecular weight distributions, the number of repetitions is set as the number of repetitions corresponding to the molecular weight with the strongest peak in the MALDI-TOF-MS mass spectrum.

[0107] The second ionizing radiation-curable resin may also contain methacrylate, if it contains acrylate. For example, the second ionizing radiation-curable resin may be a second mixture of acrylate and methacrylate, wherein the second mixture has a smaller proportion of the molar number of methacryloyl groups in the total molar number of acryloyl groups compared to the first mixture. The proportion in the second mixture is preferably 90% or less, more preferably 80% or less, of the proportion in the first mixture.

[0108] In addition to the resin-cured product, the second gloss adjustment layer 6 may also contain particles.

[0109] The particles contained in the second gloss adjustment layer 6 can be, for example, particles made of organic materials such as polyethylene (PE) wax, polypropylene (PP) wax, and resin beads; or particles made of inorganic materials such as silica, glass, alumina, titanium dioxide, zirconium oxide, calcium carbonate, and barium sulfate.

[0110] The average particle size (D50) is preferably 10 μm or less, more preferably in the range of 1 μm to 8 μm, even more preferably in the range of 2 μm to 7 μm, and most preferably in the range of 3 μm to 6 μm. When the average particle size (D50) is increased, the particles may easily detach from the second gloss adjustment layer 6, making it difficult to achieve high scratch resistance. When the particles are small, the effect of uniformly generating wrinkles becomes smaller.

[0111] Here, "average particle size" or "average particle size (D50)" refers to the median particle size (D50) measured by a laser diffraction / scattering particle size distribution measuring device. It should be noted that if the coating liquid for the second gloss adjustment layer contains particles, the second gloss adjustment layer 6 obtained from that coating liquid also contains particles. The average particle size of the particles contained in the second gloss adjustment layer 6 can be obtained by observing its cross-section, measuring the particle size of multiple particles, and averaging the results. The value obtained in this way is substantially the same as the median particle size (D50) measured by the laser diffraction / scattering particle size distribution measuring device. Therefore, the aforementioned range of average particle size can also be read as the range of the average particle size of the particles contained in the second gloss adjustment layer.

[0112] The amount of particles in the second gloss adjustment layer 6 is preferably in the range of 0.5 parts by mass to 20 parts by mass relative to 100 parts by mass of the cured resin product, more preferably in the range of 0.5 parts by mass to 10 parts by mass, further preferably in the range of 2 parts by mass to 8 parts by mass, and most preferably in the range of 2 parts by mass to 6 parts by mass.

[0113] When the amount of particles added is within the above range, the effect of uniform wrinkling is particularly significant. When too many particles are added, the particles may easily fall off from the second gloss adjustment layer 6, making it difficult to achieve high scratch resistance.

[0114] <2> Manufacturing method of decorative sheet

[0115] Decorative piece 1 is manufactured, for example, by the following method.

[0116] First, a solid ink layer 3 is formed on one surface of the raw material layer 2. The solid ink layer 3 can be formed by various printing methods such as gravure printing, offset printing, screen printing, electrostatic printing, inkjet printing, etc.; or by various coating methods such as roller coating, doctor blade coating, micro-gravure coating, mold coating, etc.

[0117] Next, a pattern ink layer 4 is formed on the solid ink layer 3. The pattern ink layer 4 can be formed by various printing methods, such as gravure printing, offset printing, screen printing, electrostatic printing, and inkjet printing. Among these, gravure printing is preferred because it can be processed at relatively high speeds and is cost-effective.

[0118] Next, on the aforementioned surface of the raw material layer 2, a first coating film composed of a coating liquid for the first gloss adjustment layer is formed in such a way as to cover the solid ink layer 3 and the pattern ink layer 4. This first coating film can be formed, for example, by various printing methods such as gravure printing, offset printing, screen printing, electrostatic printing, inkjet printing, etc.; or by various coating methods such as roller coating, doctor blade coating, micro-gravure coating, mold coating, etc.

[0119] The coating liquid for the first gloss adjustment layer contains the aforementioned first ionizing radiation-curable resin. As described above, the first ionizing radiation-curable resin is a first mixture of acrylate and methacrylate.

[0120] The coating solution for the first gloss adjusting layer may also contain other components, such as the aforementioned particles, solvents, and additives (e.g., one or more of antibacterial agents and antifungal agents) to enhance the functionality of the final product. The coating solution for the first gloss adjusting layer may also contain other additives such as ultraviolet absorbers and light stabilizers. Examples of ultraviolet absorbers include benzotriazole, benzoate, benzophenone, and triazine compounds. Examples of light stabilizers include hindered amine compounds.

[0121] In the third irradiation step described later, where the first coating film is completely cured by ultraviolet light irradiation, the coating liquid for the first gloss adjustment layer preferably also contains a photoinitiator. The photoinitiator is not particularly limited, and examples include benzophenone-based, acetophenone-based, benzoin ether-based, and thioxanthone-based photoinitiators.

[0122] Next, the first irradiation step is performed. In the first irradiation step, the first coating is irradiated with the first radiation to make the first coating semi-cured. Here, "semi-cured" means that although the coating becomes solid, the C=C bonds from the acryloyl and methacryloyl groups remain sufficiently intact.

[0123] The first radiation is, for example, ionizing radiation. As mentioned above, ionizing radiation is a beam of charged particles such as an electron beam. The first radiation can also be ultraviolet light from which the first ionizing radiation-cured resin exhibits a small absorption coefficient. The wavelength of the ultraviolet light irradiating the first coating is preferably greater than 200 nm, more preferably in the range of 230 nm to 450 nm, and even more preferably in the range of 250 nm to 400 nm.

[0124] When the first coating is irradiated with ionizing radiation or the aforementioned ultraviolet light, it can be cured substantially uniformly over its entire thickness. Therefore, unlike the second coating described later, the semi-cured first coating does not have an uneven surface.

[0125] Regarding the irradiation of the first coating with the first radiation, it is preferable that the irradiation is carried out in a manner in which the unreacted rate of the first coating, i.e., the ratio of the number of C=C bonds after irradiation with the first radiation to the number of C=C bonds before irradiation with the first radiation, is in the range of 5% to 80%, more preferably in the range of 10% to 60%, and even more preferably in the range of 15% to 50%.

[0126] Regarding the irradiation of the first coating film by the first radiation, it is preferable to perform the irradiation in a manner that is in the range of 3% to 30% relative to the minimum cumulative light intensity required for complete curing of the first coating film, more preferably in a manner that is in the range of 5% to 25%, and even more preferably in a manner that is in the range of 8% to 20%.

[0127] It should be noted that, according to one example, the minimum cumulative light intensity required for the first coating to fully cure is 10 mJ / cm². 2 Above 1000mJ / cm 2 Within the following range.

[0128] Regarding the irradiation of the first coating with the first radiation, it is preferable to perform the irradiation in a manner that is in the range of 0.2% to 50% relative to the minimum absorbed dose required for complete curing of the first coating, more preferably in a manner that is in the range of 0.5% to 40%, and even more preferably in a manner that is in the range of 1% to 30%.

[0129] It should be noted that, according to one example, the minimum absorbed dose required for complete curing of the first coating film is in the range of 5 kGy to 200 kGy.

[0130] As described above, the first ionizing radiation-curable resin contains methacrylate in addition to acrylate. Methacrylate reduces the rate of crosslinking reaction induced by the first radiation, thereby widening the process window for achieving the desired cured state.

[0131] Next, a second coating film, consisting of a coating liquid for a second gloss adjustment layer, is formed on the semi-cured first coating film. The second coating film is formed such that it partially covers the top of the first coating film. Specifically, the second coating film is formed such that the first coating film is sandwiched in between and faces the pattern ink layer 4. The second coating film can be formed by various printing methods, such as gravure printing, offset printing, screen printing, electrostatic printing, and inkjet printing. Among these, gravure printing is preferred.

[0132] The coating liquid for the second gloss adjustment layer contains the aforementioned second ionizing radiation-curable resin. As described above, according to one example, the second ionizing radiation-curable resin is an acrylate. Alternatively, according to other examples, the second ionizing radiation-curable resin is a second mixture of acrylate and methacrylate, which is a second mixture in which the molar number of methacryloyl groups is smaller in proportion to the total molar number of acryloyl groups compared to the first mixture.

[0133] The coating solution for the second gloss adjusting layer may also contain other components, such as the aforementioned particles, solvents, and additives (e.g., one or more of antibacterial agents and antifungal agents) to enhance the functionality of the final product. The coating solution for the second gloss adjusting layer may also contain other additives such as ultraviolet absorbers and light stabilizers. Examples of ultraviolet absorbers include benzotriazole, benzoate, benzophenone, and triazine compounds. Examples of light stabilizers include hindered amine compounds.

[0134] Next, the first and second coatings are irradiated with ionizing radiation or ultraviolet light to completely cure them. For example, the second and third irradiation steps described below are performed sequentially.

[0135] In the second process, the second coating is irradiated with a second type of radiation. The second type of radiation is light with a wavelength of less than 200 nm.

[0136] The second ionizing radiation-curing resin contained in the coating liquid of the second gloss adjustment layer has a high absorption coefficient for the second radiation. Therefore, the second radiation incident on the second coating film can only reach a position tens to hundreds of nm away from its outermost surface. Therefore, in the second irradiation process, a cross-linking reaction occurs in the surface area of ​​the second coating film to form an extremely thin cured film, while in other areas, no cross-linking reaction occurs and it remains uncured.

[0137] The second coating after the second irradiation process has wrinkles on its surface corresponding to the ridge 6B. The inventors believe that the wrinkles are generated on the coating surface by the second irradiation process for the following reasons.

[0138] As described above, the second radiation can only reach locations tens to hundreds of nm away from the outermost surface of the second coating. That is, the cross-linking reaction of the second ionizing radiation-cured resin occurs only on the surface of the second coating; regions farther from the outermost surface than tens to hundreds of nm remain uncured, containing highly fluid molecules. These highly fluid molecules cause the cured film to swell, increasing its volume. Due to the in-plane compressive stress generated by this volume increase, the cured film bends, resulting in wrinkles on the surface of the second coating.

[0139] It should be noted that in the second irradiation step, the surface of the portion of the first coating not covered by the second coating can also be irradiated with the second radiation. However, since the first coating is semi-cured, it is difficult for molecules to flow within the film. Therefore, no wrinkles are formed on the exposed surface of the first coating.

[0140] Furthermore, the second radiation will not reach the portion of the first coating that is covered by the second coating. Therefore, no cross-linking reaction caused by the second radiation will occur in that portion.

[0141] The second type of radiation can be extracted from excimer VUV (Vacuum Ultra Violet) light. Excimer VUV light can be generated by lamps using rare gases or rare gas halides. When high-energy electrons are applied from the outside to a lamp enclosed in a rare gas or rare gas halide gas, a large amount of discharge plasma (dielectric barrier discharge) is generated. Through this plasma discharge, the atoms of the discharge gas (rare gas) are excited and momentarily enter the excimer state. When returning from this excimer state to the ground state, light in the wavelength region specific to that excimer is emitted.

[0142] The gas used for excimer lamps only needs to emit light below 200 nm, and can be any gas previously used. As the gas, rare gases such as Xe, Ar, and Kr, as well as mixtures of rare gases and halogen gases such as ArBr and ArF, can be used. The wavelength (center wavelength) of the excimer lamp varies depending on the gas, for example, it has wavelengths of approximately 172 nm (Xe), approximately 126 nm (Ar), approximately 146 nm (Kr), approximately 165 nm (ArBr), and approximately 193 nm (ArF).

[0143] Considering the difference between the photon energy, wavelength, and binding energy of organic matter, a xenon lamp emitting excimer light with a center wavelength of 172 nm is preferred as the light source. Furthermore, considering the cost of equipment maintenance and the availability of materials, a xenon lamp is also preferred as the light source.

[0144] The second irradiation step is carried out in an atmosphere with low oxygen concentration. Oxygen has a high absorption coefficient for light below 200 nm. Therefore, the second irradiation step is preferably carried out, for example, in a nitrogen atmosphere. The oxygen concentration in the gas phase of the second irradiation step, i.e., the residual oxygen concentration in the reaction atmosphere, is preferably set to 2000 ppm or less, more preferably 1000 ppm or less.

[0145] Furthermore, oxygen in the atmosphere inhibits free radical polymerization. Therefore, the residual oxygen concentration in the reaction atmosphere affects the formation of wrinkles on the surface of the second coating. Consequently, the surface properties of the second gloss adjustment layer 6 may also change when the residual oxygen concentration in the reaction atmosphere changes.

[0146] The cumulative intensity of the second radiation is preferably set at 0.5 mJ / cm². 2 Above 200mJ / cm 2 Within the following range, more preferably at 1 mJ / cm 2 Above 100mJ / cm 2 Within the following range, it is further preferred to be set at 3mJ / cm 2 Above 50mJ / cm 2 Within the following range, the optimal setting is 5 mJ / cm. 2 Above 30mJ / cm 2 Within the following range: When the cumulative light intensity decreases, the in-plane expansion of the cured film decreases. When the cumulative light intensity increases, the surface condition of the second coating deteriorates.

[0147] In the third irradiation step, the second coating is irradiated with a third type of radiation. The third type of radiation is either ionizing radiation or ultraviolet light with a wavelength longer than the light irradiated in the second irradiation step. The third type of radiation can be derived from the first type of radiation mentioned above.

[0148] In the third irradiation step, a cross-linking reaction occurs across the entire thickness of each of the first and second coatings. At the start of the third irradiation step, since the first coating is in a semi-cured state, a cross-linking reaction can occur between the molecules contained in the first coating and the molecules contained in the second coating at the point of contact between the two coatings. Therefore, high adhesion can be achieved between the first gloss adjustment layer 5 and the second gloss adjustment layer 6.

[0149] The cumulative intensity of the third radiation is preferably set at 10 mJ / cm². 2 Above 500mJ / cm 2 Within the following range, more preferably at 50 mJ / cm 2 Above 400mJ / cm 2 Within the following range, it is further preferred to be set at 100 mJ / cm 2 Above 300mJ / cm 2 Within the following range.

[0150] The third radiation exposure is preferably carried out in a manner with an absorbed dose of 5 kGy to 200 kGy, more preferably in a manner with an absorbed dose of 10 kGy to 150 kGy, and even more preferably in a manner with an absorbed dose of 15 kGy to 100 kGy.

[0151] In the third irradiation step, if a layer with sufficient intensity cannot be obtained by irradiation with only a single type of radiation, the type of the third radiation can be changed simultaneously. For example, irradiation with ionizing radiation can be performed first, followed by irradiation with ultraviolet light with a wavelength longer than that irradiated in the second irradiation step. Alternatively, irradiation with ultraviolet light with a wavelength longer than that irradiated in the second irradiation step can be performed first, followed by irradiation with ionizing radiation. Alternatively, irradiation with ultraviolet light with a wavelength longer than that irradiated in the second irradiation step can be performed first, followed by irradiation with ultraviolet light with an even longer wavelength.

[0152] As described above, decorative piece 1 is obtained. It should be noted that in decorative piece 1 obtained by the above method, there is no interface between the core portion 6A and the ridge portion 6B; they are integrally formed.

[0153] <3> Effect

[0154] The decorative piece 1 described above includes a first gloss adjustment layer 5 and a second gloss adjustment layer 6 that partially covers it. The specular gloss GS (60°) of the first gloss adjustment layer 5 and the second gloss adjustment layer 6 are different. Here, the specular gloss GS (60°) of the second gloss adjustment layer 6 is lower than that of the first gloss adjustment layer 5. In particular, when the second gloss adjustment layer 6 is formed with the aforementioned surface properties, the difference between the specular gloss GS (60°) of the first gloss adjustment layer 5 and the specular gloss GS (60°) of the second gloss adjustment layer 6 can be increased. Their difference in gloss helps to create a three-dimensional effect with unevenness.

[0155] Furthermore, in decorative piece 1, the second gloss adjustment layer 6 is aligned with the shape and position of the pattern ink layer 4. Therefore, decorative piece 1 can exhibit a three-dimensional effect, with the portion corresponding to the pattern ink layer 4 as raised areas and the other portions as recessed areas. Thus, by appropriately selecting the colors of the solid ink layer 3 and the pattern ink layer 4, decorative piece 1 can achieve a design aesthetic approaching, for example, that of natural wood or natural stone.

[0156] Furthermore, in decorative sheet 1, the first gloss adjustment layer 5 contains only the cured product of the first ionizing radiation-curable resin as the resin curing product. The first ionizing radiation-curable resin is a first mixture of acrylate and methacrylate. Acrylate helps improve scratch resistance, and methacrylate helps improve the adhesion between the first gloss adjustment layer 5 and the second gloss adjustment layer 6. Therefore, decorative sheet 1 exhibits excellent scratch resistance and adhesion between the gloss adjustment layers.

[0157] Furthermore, compared to the raised and recessed structures formed by mechanical processing such as embossing, the raised and recessed structure including the ridges 6B produced on the second gloss adjustment layer 6 by the above method is fine. Because the decorative piece 1 has such a fine raised and recessed structure on the second gloss adjustment layer 6, it has a matte finish and excellent fingerprint resistance.

[0158] <4> Variations

[0159] Decorative piece 1 can be deformed in various ways.

[0160] For example, the second gloss adjustment layer 6 can be identical in shape and position to the portion of the solid ink layer 3 that is not covered by the pattern ink layer 4. In this way, the decorative piece 1 can exhibit a three-dimensional effect with the portion corresponding to the pattern ink layer 4 as a concave part and the other parts as convex parts.

[0161] In the decorative piece 1 described above, the protrusions on the upper surface of the second gloss adjustment layer 6 are ridge-shaped. These protrusions may not be ridge-shaped. For example, each of these protrusions may be part of a particle.

[0162] In the aforementioned decorative piece 1, the area on the upper surface of the first gloss adjustment layer 5 that is not covered by the second gloss adjustment layer 6 is flat. As long as the aforementioned relationship regarding gloss is maintained, a textured structure can also be provided in this area. This textured structure can be similar to the aforementioned ridge 6B, or it can be a structure formed by arranging multiple protrusions, each composed of a portion of a particle.

[0163] Example

[0164] Hereinafter, examples of the present invention will be described. It should be noted that the “particle size” described below refers to the “average particle size (D50)” mentioned above.

[0165] <Example 1>

[0166] The reference was created using the following method. Figures 1 to 4 Instructions for decorative piece 1. First, prepare a piece with a unit area mass of 50g / m². 2Impregnated paper (GFR-506: manufactured by Kojin Co., Ltd.) was used as the base material layer 2. Using oil-based nitrocellulose resin gravure printing ink (PCNT (PCRNT) various colors: manufactured by Toyo Ink Co., Ltd.), a solid ink layer 3 and a pattern ink layer 4 were sequentially formed on one side of the base material layer 2. The pattern of the pattern ink layer 4 was set as a wood grain pattern.

[0167] Next, a coating liquid for a first gloss adjustment layer having the following composition is applied to the solid ink layer 3 and the pattern ink layer 4. The coating liquid for the first gloss adjustment layer is applied in such a way that the thickness of the first gloss adjustment layer 5 is 5 μm.

[0168] (Coating liquid for the first gloss adjustment layer)

[0169] • Ionizing radiation-cured resin R1

[0170] Type: Trimethylolpropane EO-modified triacrylate (EO3 molar addition)

[0171] Product Name: Miramer M3130 (Made by Miwon)

[0172] Mixture: 50 parts by weight

[0173] • Ionizing radiation-cured resin R2

[0174] Type: Methoxylated polyethylene glycol (400) methacrylate

[0175] Product Name: NK Ester M-90G (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0176] Mixture: 50 parts by weight

[0177] ·particle

[0178] Product Name: SYLYSIA 250N (Manufactured by Fuji Silysia Chemical Ltd.)

[0179] Particle size: 5μm

[0180] Mixture: 15 parts by weight

[0181] Then, the first irradiation process is performed. Specifically, the first coating film, which is composed of a coating liquid for the first gloss adjustment layer, is irradiated with an electron beam as ionizing radiation, such that the absorbed dose of the first coating film is 10 kGy. As a result, the first coating film is semi-cured.

[0182] Next, a coating liquid for a second gloss adjustment layer with the following composition is printed on the portion of the first coating film corresponding to the pattern ink layer 4. The coating liquid for the second gloss adjustment layer is printed in such a way that the thickness of the second gloss adjustment layer 6 is 5 μm.

[0183] (Coating liquid for the second gloss adjustment layer)

[0184] • Ionizing radiation-cured resin

[0185] Type: Trimethylolpropane EO-modified triacrylate (EO6 molar addition)

[0186] Product Name: Miramer M3160 (Made by Miwon)

[0187] Mixture: 100 parts by weight

[0188] ·particle

[0189] Product Name: SYLYSIA 250N (Manufactured by Fuji Silysia Chemical Ltd.)

[0190] Particle size: 5μm

[0191] Mixture: 0.5 parts by weight

[0192] Next, the second irradiation process is carried out. Specifically, an Xe excimer lamp is used in a nitrogen atmosphere with atmospheric pressure and an oxygen concentration of 500 ppm to achieve a cumulative light intensity of 50 mJ / cm². 2 The surfaces of the first coating and the second coating, which is composed of a coating liquid for the second gloss adjustment layer, are irradiated with ultraviolet light of a wavelength of 172 nm. As a result, wrinkles are generated on the surface of the second coating.

[0193] Next, the third irradiation process is carried out. Specifically, the first and second coatings are irradiated with 100 kGy of ionizing radiation to completely cure them, thereby forming the first gloss adjustment layer 5 and the second gloss adjustment layer 6.

[0194] Decorative piece 1 was obtained through the above process.

[0195] <Example 2>

[0196] In the coating liquid for the first gloss adjustment layer, the proportion of ionizing radiation-curable resin R1 was set to 80 parts by weight, and the proportion of ionizing radiation-curable resin R2 was set to 20 parts by weight. Otherwise, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0197] <Example 3>

[0198] In the coating liquid for the first gloss adjustment layer, the proportion of ionizing radiation-curable resin R1 was set to 90 parts by mass, and the proportion of ionizing radiation-curable resin R2 was set to 10 parts by mass. Otherwise, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0199] <Example 4>

[0200] Using the following resin as the ionizing radiation curable resin R2, in the coating liquid for the first gloss adjustment layer, the proportion of ionizing radiation curable resin R1 was set to 90 parts by mass and the proportion of ionizing radiation curable resin R2 was set to 10 parts by mass. Otherwise, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0201] • Ionizing radiation-cured resin R2

[0202] Type: Isoborneol methacrylate

[0203] Product Name: Light Ester IB-X (Made by Kyoei Chemical Co., Ltd.)

[0204] <Example 5>

[0205] Except for using the following resin as the ionizing radiation curable resin R2, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0206] • Ionizing radiation-cured resin R2

[0207] Type: EO-modified bisphenol A dimethacrylate (EO 10 molar addition)

[0208] Product Name: NK Ester BPE-500 (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0209] <Example 6>

[0210] Using the following resin as the ionizing radiation curable resin R2, in the coating liquid for the first gloss adjustment layer, the proportion of ionizing radiation curable resin R1 was set to 80 parts by weight, and the proportion of ionizing radiation curable resin R2 was set to 20 parts by weight. Otherwise, a reference sample was manufactured using the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0211] • Ionizing radiation-cured resin R2

[0212] Type: EO-modified bisphenol A dimethacrylate (EO 10 molar addition)

[0213] Product Name: NK Ester BPE-500 (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0214] <Example 7>

[0215] Using the following resin as the ionizing radiation curable resin R2, in the coating liquid for the first gloss adjustment layer, the proportion of ionizing radiation curable resin R1 was set to 90 parts by mass and the proportion of ionizing radiation curable resin R2 was set to 10 parts by mass. Otherwise, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0216] • Ionizing radiation-cured resin R2

[0217] Type: EO-modified bisphenol A dimethacrylate (EO 10 molar addition)

[0218] Product Name: NK Ester BPE-500 (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0219] <Example 8>

[0220] Using the following resin as the ionizing radiation curable resin R2, in the coating liquid for the first gloss adjustment layer, the proportion of ionizing radiation curable resin R1 was set to 80 parts by weight, and the proportion of ionizing radiation curable resin R2 was set to 20 parts by weight. Otherwise, a reference sample was manufactured using the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0221] • Ionizing radiation-cured resin R2

[0222] Type: Polyethylene glycol (200) dimethacrylate

[0223] Product Name: NK Ester 4G (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0224] <Example 9>

[0225] Except for using the following resin as the ionizing radiation curable resin R2, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0226] • Ionizing radiation-cured resin R2

[0227] Type: Trimethylolpropane (EO) modified trimethacrylate (EO3 molar addition)

[0228] Product Name: NK Ester TMPT-3EO (manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0229] <Example 10>

[0230] Except for using the following resin as the ionizing radiation curable resin R2, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0231] • Ionizing radiation-cured resin R2

[0232] Type: Trimethylolpropane (PO) modified trimethacrylate (PO3 molar addition)

[0233] Product Name: NK Ester TMPT-3PO (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0234] <Example 11>

[0235] Except that the amount of particles in the coating liquid for the second gloss adjustment layer was set to 20 parts by mass, a reference was manufactured using the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0236] <Example 12>

[0237] Except for the following aspects, a reference was created using the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0238] That is, in this example, the following resin was used as an ionizing radiation curing resin in the coating liquid for the second gloss adjustment layer.

[0239] • Ionizing radiation-cured resin

[0240] Type: Trimethylolpropane EO-modified triacrylate (EO3 molar addition)

[0241] Product Name: Miramer M3130 (Made by Miwon)

[0242] Then, in the second irradiation step, an Xe excimer lamp is used in a nitrogen atmosphere at atmospheric pressure and an oxygen concentration of 200 ppm to achieve a cumulative light intensity of 100 mJ / cm². 2 The surfaces of the first coating and the second coating, which is composed of a coating liquid for the second gloss adjustment layer, are irradiated with ultraviolet light of a wavelength of 172 nm.

[0243] <Example 13>

[0244] Except that the following resin was used as an ionizing radiation curable resin in the coating liquid for the second gloss adjustment layer, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0245] • Ionizing radiation-cured resin

[0246] Type: Trimethylolpropane EO-modified triacrylate (EO 15 molar addition)

[0247] Product Name: SR9035 (Made by Sartomer)

[0248] <Example 14>

[0249] Except that the following resin was used as an ionizing radiation curable resin in the coating liquid for the second gloss adjustment layer, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0250] • Ionizing radiation-cured resin

[0251] Type: Ethylene glycol diacrylate (EO9 molar addition)

[0252] Product Name: Light Acrylate 9EG-A (Manufactured by Kyoei Chemical Co., Ltd.)

[0253] <Example 15>

[0254] Except for the following aspects, a reference was created using the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0255] That is, in this example, the following resin was used as an ionizing radiation curing resin in the coating liquid for the second gloss adjustment layer.

[0256] • Ionizing radiation-cured resin

[0257] Type: Ethoxylated pentaerythritol tetraacrylate (EO35 molar addition)

[0258] Product Name: NK Ester ATM-35E (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0259] Then, in the second irradiation step, an Xe excimer lamp is used in a nitrogen atmosphere at atmospheric pressure and an oxygen concentration of 200 ppm to achieve a cumulative light intensity of 50 mJ / cm². 2 The surfaces of the first coating and the second coating, which is composed of a coating liquid for the second gloss adjustment layer, are irradiated with ultraviolet light of a wavelength of 172 nm.

[0260] <Example 16>

[0261] Except for the following aspects, a reference was created using the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0262] That is, in this example, the following resin was used as an ionizing radiation curing resin in the coating liquid for the second gloss adjustment layer.

[0263] • Ionizing radiation-cured resin

[0264] Type: Ethoxylated pentaerythritol hexaacrylate (EO12 molar addition)

[0265] Product Name: NK Ester A-DPH-12E (Manufactured by Shin-Nakamura Chemical Co., Ltd.)

[0266] Then, in the second irradiation step, an Xe excimer lamp is used in a nitrogen atmosphere with atmospheric pressure and an oxygen concentration of 100 ppm to achieve a cumulative light intensity of 150 mJ / cm². 2 The surfaces of the first coating and the second coating, which is composed of a coating liquid for the second gloss adjustment layer, are irradiated with ultraviolet light of a wavelength of 172 nm.

[0267] <Example 17>

[0268] The coating liquid for the second gloss adjustment layer was printed in such a way that the thickness of the second gloss adjustment layer 6 was 2 μm. Otherwise, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0269] <Example 18>

[0270] The coating liquid for the second gloss adjustment layer was printed in such a way that the thickness of the second gloss adjustment layer 6 was 20 μm. Otherwise, a reference was manufactured by the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0271] <Example 19>

[0272] Except for the following aspects, a reference was created using the same method as in Example 1. Figures 1 to 4 Decorative sheet 1 is explained. That is, in this example, particles are omitted in the coating liquid for the second gloss adjustment layer. Then, the coating liquid for the second gloss adjustment layer is printed in such a way that the thickness of the second gloss adjustment layer 6 is 3μm.

[0273] <Example 20>

[0274] Except that the particle composition of the second gloss adjustment layer in the coating liquid was set to 10 parts by mass, a reference was manufactured using the same method as in Example 1. Figures 1 to 4 Decorative piece 1 as described.

[0275] <Example 21>

[0276] Except for the following aspects, a reference was created using the same method as in Example 1. Figures 1 to 4 Decorative sheet 1 is described below. Specifically, in this example, the particle composition of the coating liquid for the first gloss adjustment layer is set to 10 parts by mass. Additionally, in this example, the following coating liquid for the second gloss adjustment layer is used.

[0277] (Coating liquid for the second gloss adjustment layer)

[0278] • Ionizing radiation-cured resin 1

[0279] Type: Trimethylolpropane EO-modified triacrylate (EO6 molar addition)

[0280] Product Name: Miramer M3160 (Made by Miwon)

[0281] Formula: 60 parts by weight

[0282] • Ionizing radiation-cured resin 2

[0283] Type: Dipentaerythritol hexaacrylate

[0284] Product Name: Miramer M600 (Made by Miwon)

[0285] Formula: 40 parts by weight

[0286] ·particle

[0287] Product Name: SYLYSIA 250N (Manufactured by Fuji Silysia Chemical Ltd.)

[0288] Particle size: 5μm

[0289] Mixture: 0.5 parts by weight

[0290] <Example 22>

[0291] Except for the following aspects, a reference was created using the same method as in Example 1. Figures 1 to 4 Decorative sheet 1 is described below. Specifically, in this example, the particle composition of the coating liquid for the first gloss adjustment layer is set to 5 parts by mass. Additionally, in this example, the following coating liquid for the second gloss adjustment layer is used.

[0292] (Coating liquid for the second gloss adjustment layer)

[0293] • Ionizing radiation-cured resin 1

[0294] Type: Trimethylolpropane EO-modified triacrylate (EO6 molar addition)

[0295] Product Name: Miramer M3160 (Made by Miwon)

[0296] Formula: 40 parts by weight

[0297] • Ionizing radiation-cured resin 2

[0298] Type: Dipentaerythritol hexaacrylate

[0299] Product Name: Miramer M600 (Made by Miwon)

[0300] Formula: 60 parts by weight

[0301] ·particle

[0302] Product Name: SYLYSIA 250N (Manufactured by Fuji Silysia Chemical Ltd.)

[0303] Particle size: 5μm

[0304] Mixture: 0.5 parts by weight

[0305] <Example 23>

[0306] Except for the following aspects, a reference was created using the same method as in Example 1. Figures 1 to 4 Decorative sheet 1 is described below. Specifically, in this example, the particle composition of the coating liquid for the first gloss adjustment layer is set to 10 parts by mass. Furthermore, in this example, the following coating liquid for the second gloss adjustment layer is used. The coating liquid for the second gloss adjustment layer is printed such that the thickness of the second gloss adjustment layer 6 is 14 μm.

[0307] (Coating liquid for the second gloss adjustment layer)

[0308] • Ionizing radiation-cured resin 1

[0309] Type: Trimethylolpropane EO-modified triacrylate (EO6 molar addition)

[0310] Product Name: Miramer M3160 (Made by Miwon)

[0311] Formula: 40 parts by weight

[0312] • Ionizing radiation-cured resin 2

[0313] Type: Dipentaerythritol hexaacrylate

[0314] Product Name: Miramer M600 (Made by Miwon)

[0315] Formula: 60 parts by weight

[0316] ·particle

[0317] Product Name: SYLYSIA 250N (Manufactured by Fuji Silysia Chemical Ltd.)

[0318] Particle size: 5μm

[0319] Blending ratio: 0.5 parts by mass

[0320] <Comparative Example 1>

[0321] A decorative sheet similar to the one described in the reference was produced in the same manner as in Example 1, except that the radiation-curable resin R2 was omitted from the coating liquid for the first gloss adjustment layer. Figures 1 to 4 A decorative sheet similar to the one described in the reference was produced in the same manner as in Example 1, except that the radiation-curable resin R2 was omitted from the coating liquid for the first gloss adjustment layer.

[0322] <Comparative Example 2>

[0323] A decorative sheet similar to the one described in the reference was produced in the same manner as in Example 1, except that the radiation-curable resin R1 was omitted from the coating liquid for the first gloss adjustment layer. Figures 1 to 4 A decorative sheet similar to the one described in the reference was produced in the same manner as in Example 1, except that the radiation-curable resin R1 was omitted from the coating liquid for the first gloss adjustment layer.

[0324] <Evaluation>

[0325] The above-described decorative sheets were evaluated as follows. It should be noted that decorative sheets evaluated as "AAA", "AA", or "A" have no problems in actual use and are therefore considered acceptable.

[0326] (1) Thickness of the gloss adjustment layer

[0327] The thickness of the second gloss adjustment layer was measured in the same manner as described above.

[0328] Specifically, the decorative sheet was embedded in a resin such as a cold-curing epoxy resin or a UV-curable resin, and the resin was fully cured. Then, it was cut to expose the cross-section of the decorative sheet, and a measurement surface was obtained by mechanical polishing.

[0329] Next, a cross-section of the second gloss adjustment layer was photographed using a scanning electron microscope SIGMA500 manufactured by Carl Zeiss Microscopy GmbH. When taking this photograph, the acceleration voltage was set to 0.5 keV (low acceleration voltage), the imaging mode was set to the SE2 mode, and the magnification was set to 2000 times. It should be noted that the measurement sample was not sputtered.

[0330] Next, based on this cross-sectional image, the size of the second gloss adjustment layer in the width direction of the ridge portion and the area of the cross-section of the second gloss adjustment layer were determined. The thickness of the second gloss adjustment layer was calculated by dividing this area by the above-mentioned size. The thickness obtained in this way is equal to the thickness of the coating film formed from the coating liquid for the second gloss adjustment layer.

[0331] In addition, the thickness of the first gloss adjustment layer was measured in the same manner as described above.

[0332] (2) Glossiness

[0333] Regarding gloss, the specular gloss GS (60°) was measured using a micro-gloss 60°xs (manufactured by BYK). The "60° gloss value" in Tables 1 to 5 below represents the specular gloss GS (60°).

[0334] (3) Fit

[0335] The adhesion of the second gloss adjusting layer to the first gloss adjusting layer was evaluated using the cross-cut test specified in JIS K5400 (obsolete). Here, 100 squares were cut in a grid pattern at 1mm intervals on the surface of the decorative sheet, the depth of which exceeded the interface between the first and second gloss adjusting layers. This created a checkerboard pattern of 100 squares. Next, adhesive tape was applied to the surface of the decorative sheet and then peeled off. The number of remaining squares in the decorative sheet was then counted, and this number was evaluated against the following criteria to assess the adhesion.

[0336] AAA: There are 100 remaining squares.

[0337] AA: The number of remaining squares is in the range of 95 to 99.

[0338] A: The number of remaining squares is in the range of 90 to 94.

[0339] B: The number of remaining squares is less than 89.

[0340] (4) Damage resistance

[0341] Each decorative panel was adhered to the wood substrate B using a urethane-based adhesive. Then, a stainless steel wool abrasion test was performed as an evaluation of scratch resistance. Specifically, the decorative panel was rubbed back and forth 20 times with stainless steel wool while a load of 100g was applied, and any damage or changes in gloss on the surface of the decorative panel were visually confirmed.

[0342] The evaluation criteria are as follows.

[0343] AAA: No damage or change in gloss was observed on the surface.

[0344] AA: A portion of the surface has experienced minor damage or a change in gloss.

[0345] A: The surface has suffered minor damage or a change in gloss.

[0346] B: The surface has obvious damage or changes in gloss.

[0347] (5) Stain resistance

[0348] As an evaluation of stain resistance, the Stain A test as specified in the Japanese Agricultural Standards (JAS) was conducted. Specifically, 10mm wide lines were drawn on the protective layer of each decorative piece using blue ink, black quick-drying ink, and red crayon, respectively, and left for 4 hours. Then, the lines using the blue ink, black quick-drying ink, and red crayon were wiped with a cloth containing ethanol.

[0349] The evaluation criteria are as follows.

[0350] AAA: The lines of various colors can be easily wiped clean.

[0351] AA: It can wipe part of the lines of each color, but some dirt will remain in some areas.

[0352] A: You can wipe part of the lines of each color, but some will still have dirt left.

[0353] B: Do not wipe the lines of different colors.

[0354] The evaluation results are shown in Tables 1 to 5. It should be noted that in Tables 1 to 5, "the proportion of moles of methacryloyl groups" represents the proportion of moles of methacryloyl groups in the total number of moles of acryloyl groups and the total number of moles of methacryloyl groups.

[0355]

[0356]

[0357]

[0358]

[0359]

[0360] As shown in Tables 1 to 5, the decorative sheets involved in Examples 1 to 23 exhibited sufficient performance in terms of adhesion, scratch resistance, and stain resistance. In contrast, the sheet involved in Comparative Example 1 was insufficient in all aspects of adhesion, scratch resistance, and stain resistance. Furthermore, the sheet involved in Comparative Example 2 exhibited sufficient performance in terms of adhesion, but insufficient performance in terms of scratch resistance and stain resistance.

[0361] Explanation of symbols

[0362] 1… Decorative piece, 2… Raw material layer, 3… Solid ink layer, 4… Pattern ink layer, 5… First gloss adjustment layer, 6… Second gloss adjustment layer, 6A… Core, 6B… Ridge, 11… Decorative material, B… Substrate, C… Position, D… Position.

Claims

1. A decorative sheet provided with a base material layer and a surface protective layer, the surface protective layer comprising: a first gloss adjusting layer provided on the base material layer, containing only a cured product of a first ionizing radiation-curable resin as a resin cured product, the first ionizing radiation-curable resin being a first mixture of an acrylate and a methacrylate; and a second gloss adjusting layer partially covering the upper face of the first gloss adjusting layer, containing only a cured product of a second ionizing radiation-curable resin as a resin cured product, having a lower specular gloss GS (60°) than the first gloss adjusting layer.

2. The decorative sheet according to claim 1, wherein in the first ionizing radiation-curable resin, the proportion of the number of moles of methacryloyl groups in the total of the number of moles of acryloyl groups and the number of moles of methacryloyl groups is in the range of 3% or more and 50% or less.

3. The decorative sheet according to claim 1 or 2, wherein the methacrylate is a monofunctional, difunctional or trifunctional methacrylate.

4. The decorative sheet according to any one of claims 1 to 3, wherein the second ionizing radiation-curable resin is an acrylate, or is a second mixture of an acrylate and a methacrylate, the proportion of the number of moles of methacryloyl groups in the total of the number of moles of acryloyl groups and the number of moles of methacryloyl groups being smaller in the second mixture than in the first mixture.

5. The decorative sheet according to any one of claims 1 to 4, wherein the second ionizing radiation-curable resin contains a difunctional or higher acrylate having a repeating structure.

6. The decorative sheet according to claim 5, wherein the repeating structure has a repeating number of 3 or more.

7. The decorative sheet according to any one of claims 1 to 6, wherein a concavo-convex structure comprising a plurality of ridge-shaped portions each protruding in a ridge shape is provided on the surface of the second gloss adjusting layer.

8. The decorative sheet according to claim 7, wherein the ratio RSm / Ra of the average length RSm of the roughness curve elements of the concavo-convex structure to the arithmetic average roughness Ra is in the range of 10 or more and 900 or less.

9. The decorative sheet according to any one of claims 1 to 8, wherein the thickness of each of the first gloss adjusting layer and the second gloss adjusting layer is in the range of 2 μm or more and 20 μm or less.

10. The decorative sheet according to any one of claims 1 to 9, wherein the second gloss adjusting layer further contains particles having an average particle diameter of 10 μm or less.

11. The decorative sheet according to claim 10, wherein in the case where the mass of the second ionizing radiation-curable resin is taken as 100 parts by mass, the mass of the particles is in the range of 0.5 parts by mass or more and 20 parts by mass or less.

12. The decorative sheet according to any one of claims 1 to 11, wherein the specular gloss GS (60°) of the first gloss adjusting layer is 3 or more, and the specular gloss GS (60°) of the second gloss adjusting layer is 20 or less.

13. The decorative sheet according to any one of claims 1 to 12, wherein The difference between the specular glossiness GS (60°) of the first gloss adjusting layer and the specular glossiness GS (60°) of the second gloss adjusting layer is 1 or more.

14. A decorative material comprising: the decorative sheet according to any one of claims 1 to 13, and a base material to which the decorative sheet is attached.

15. A method for manufacturing a decorative sheet, comprising: forming a first coating film on a raw material layer, wherein the first coating film contains only a first ionizing radiation-curable resin as a resin, the first ionizing radiation-curable resin being a first mixture of an acrylate and a methacrylate; performing a first irradiation process of irradiating ionizing radiation or ultraviolet light to the first coating film to semi-cure the first coating film; forming a second coating film on the semi-cured first coating film in a manner to partially cover the upper surface of the first coating film, wherein the second coating film contains only a second ionizing radiation-curable resin as a resin; and irradiating ionizing radiation or ultraviolet light to the first coating film and the second coating film to fully cure the first coating film and the second coating film.

16. The method for manufacturing a decorative sheet according to claim 15, wherein the full curing of the first coating film and the second coating film includes: a second irradiation process of irradiating light having a wavelength of 200 nm or less to the second coating film; then, a third irradiation process of irradiating ionizing radiation to the first coating film and the second coating film, or irradiating ultraviolet light having a longer wavelength than the light irradiated in the second irradiation process.

Images