Decorative sheet

Abstract

Provided is a decorative sheet that is minimally glossy and is smooth by touch. A decorative sheet (1) comprises a substrate layer (2) and a surface protection layer (5) which is provided on one surface of the substrate (2). The surface protection layer (5) has, on the surface thereof, a structure of projections and recesses, which includes multiple ridge sections each protruding like a ridge. The structure of projections and recesses of the surface protection layer (5) has a protruding mountain part height Rpk of less than 3.5 μm. An absorption spectrum of the surface protection layer (5) as determined by Fourier infrared spectroscopic analysis shows that the ratio I1095 / I1725, which is the ratio between the maximum value I1095 in the wave number range from 1085 to 1105 cm-1 and the maximum value I1725 in the wave number range from 1715 to 1735 cm-1, is at least 0.65.

Description

Decorative sheet

[0001] The present invention relates to a decorative sheet.

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

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

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

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

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

[0007] Furthermore, decorative sheets are generally subjected to processes such as cutting and bending in order to form decorative materials such as decorative plates, and therefore it is preferable that the decorative sheets have processability that can withstand these processes.

[0008] As such, a decorative sheet that takes into consideration design (low gloss), scratch resistance, and stain resistance is disclosed in, for example, Patent Document 1.

[0009] Japanese Patent Application Publication No. 2019-119138

[0010] An object of the present invention is to provide a decorative sheet that has low gloss and provides a smooth feel.

[0011] According to one aspect of the present invention, there is provided a substrate layer and a surface protective layer provided on one surface of the substrate layer, wherein the surface of the surface protective layer is provided with an uneven structure including a plurality of ridge-like portions each protruding in a ridge-like shape, and the uneven structure of the surface protective layer has a protruding peak height Rpk of less than 3.5 μm, and the absorption spectrum obtained by Fourier infrared spectroscopy of the surface protective layer is 1085 to 1105 cm －１ The maximum value in the wavenumber range of I １０９５ and 1715 to 1735 cm －１ The maximum value in the wavenumber range of I １７２５ Relative to I １０９５ / I １７２５ A decorative sheet having a tensile strength of 0.65 or greater is provided.

[0012] According to another aspect of the present invention, the ratio I １０９５ / I １７２５ The decorative sheet according to the above aspect is provided in which the tensile strength is 3.5 or less.

[0013] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the protruding peak height Rpk is 0.5 μm or more.

[0014] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the uneven structure of the surface protective layer has a mean length RSm of roughness curve elements of 800 μm or less.

[0015] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the uneven structure of the surface protective layer has a mean length RSm of roughness curve elements of 350 μm or less.

[0016] According to yet another aspect of the present invention, there is provided a decorative sheet according to the above aspect, wherein the average length RSm is 10 μm or more.

[0017] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the thickness of the surface protective layer is 2 μm or more and 15 μm or less.

[0018] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the thickness of the surface protective layer is 2 μm or more and less than 10 μm.

[0019] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the gloss of the surface protective layer is 20.0 or less.

[0020] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the gloss of the surface protective layer is less than 10.0.

[0021] According to yet another aspect of the present invention, there is provided a decorative sheet relating to any of the above aspects, wherein at least some of the multiple ridge portions are adjacent in the width direction, and at the position where at least some of the multiple ridge portions are adjacent in the width direction, a cross section parallel to the width direction and the thickness direction of the surface protection layer has a sinusoidal shape in the portion where the uneven structure is provided.

[0022] According to yet another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, wherein the surface protective layer contains a cured product of an ionizing radiation curable resin.

[0023] According to yet another aspect of the present invention, there is provided a decorative sheet according to the above aspect, wherein the ionizing radiation curable resin is an acrylate containing a repeating unit as a main component, the repeating unit is any one of ethylene oxide, propylene oxide, and ε-caprolactone, and the number of repetitions of the repeating unit is 3 or more.

[0024] According to yet another aspect of the present invention, there is provided a decorative sheet according to the above aspect, wherein the ionizing radiation curable resin is mainly composed of an acrylate, the acrylate includes a repeating structure, the repeating structure is any one of ethylene oxide, propylene oxide, and ε-caprolactone, and the repeating structure has a repeat count of 3 or more, and a mono- to hexa-functional second acrylate.

[0025] According to yet another aspect of the present invention, there is provided a decorative material comprising a decorative sheet according to any one of the above aspects and a substrate to which the decorative sheet is attached.

[0026] According to the present invention, it is possible to provide a decorative sheet that has low gloss and provides a smooth feel to the touch.

[0027] Fig. 1 is a cross-sectional view of a decorative material including a decorative sheet according to one embodiment of the present invention. Fig. 2 is a cross-sectional view of a surface protective layer included in the decorative sheet of Fig. 1. Fig. 3 is a microscope image of a surface protective layer included in a decorative sheet according to one example of the present invention.

[0028] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The embodiments described below are more specific embodiments of any of the above aspects. The following items can be incorporated into each of the above aspects, either singly or in combination.

[0029] Furthermore, the embodiments shown below are merely examples of configurations for embodying the technical idea of ​​the present invention, and the technical idea of ​​the present invention is not limited by the materials, shapes, structures, etc. of the components described below. Various modifications can be made to the technical idea of ​​the present invention within the technical scope defined by the claims.

[0030] In the drawings, elements having the same or similar functions are denoted by the same reference numerals, and redundant explanations will be omitted. Furthermore, the drawings are schematic, and the relationship between dimensions in one direction and dimensions in another direction, and the relationship between the dimensions of one member and the dimensions of another member, etc. may differ from the actual relationship.

[0031] <1> Decorative material and decorative sheet Fig. 1 is a cross-sectional view of a decorative material including a decorative sheet according to one embodiment of the present invention. Fig. 2 is a cross-sectional view of a surface protective layer included in the decorative sheet of Fig. 1. Fig. 3 is a micrograph of a surface protective layer included in a decorative sheet according to one example of the present invention.

[0032] The cross section shown in Fig. 2 is a cross section along the thickness direction of the surface protection layer, and the micrograph in Fig. 3 is a plan view photograph obtained by a laser microscope (OLS-4000 manufactured by Olympus Corporation).

[0033] The decorative material 11 shown in Figure 1 includes a substrate B and a decorative sheet 1 attached thereto. Here, the decorative material 11 is a decorative board. The decorative board may be a flat plate, or may be curved or folded. The decorative material 11 may have a shape other than a plate.

[0034] Here, the substrate B is a plate material. The plate material is, for example, a wood board, an inorganic board, a metal plate, or a composite board made of multiple materials. The substrate B may have a shape other than a plate.

[0035] The decorative sheet 1 includes a base fabric layer 2, a design layer 3, a transparent resin layer 4, a surface protective layer 5, an adhesive layer 7, a primer layer 6, and a concealing layer 8. The design layer 3, adhesive layer 7, transparent resin layer 4, and surface protective layer 5 are provided in this order from the base fabric layer 2 side on the surface of the base fabric layer 2 opposite the surface facing the substrate B. The concealing layer 8 and primer layer 6 are provided in this order from the base fabric layer 2 side on the surface of the base fabric layer 2 facing the substrate B. One or more of the design layer 3, transparent resin layer 4, primer layer 6, adhesive layer 7, and concealing layer 8 may be omitted. Below, the elements included in the decorative sheet 1 will be explained in order.

[0036] <1.1> Raw Fabric Layer The raw fabric layer 2 or its material can be any material selected from, for example, paper, synthetic resin, synthetic resin foam, rubber, nonwoven fabric, synthetic paper, metal foil, etc. Examples of paper include tissue paper, titanium paper, and resin-impregnated paper. Examples of synthetic resins include polyethylene, polypropylene, polybutylene, polystyrene, polycarbonate, polyester, polyamide, ethylene-vinyl acetate copolymer, polyvinyl alcohol, and acrylic. Examples of rubber include ethylene-propylene copolymer rubber, ethylene-propylene-diene copolymer rubber, styrene-butadiene copolymer rubber, styrene-isoprene-styrene block copolymer rubber, styrene-butadiene-styrene block copolymer rubber, and polyurethane. Examples of nonwoven fabric include organic and inorganic nonwoven fabrics. Examples of metals for the metal foil include aluminum, iron, gold, and silver.

[0037] The thickness of the raw fabric layer 2 is preferably within the range of 20 μm to 250 μm, taking into consideration the ease of printing and costs.

[0038] <1.2> Primer Layer When an olefin-based resin is used as the material of the raw fabric layer 2, the surface of the raw fabric layer 2 is often in an inactive state. Therefore, in this case, it is preferable to provide a primer layer 6 between the raw fabric layer 2 and the substrate B. When the raw fabric layer 2 is made of an olefin-based material, the primer layer 6 may be omitted, and the raw fabric layer 2 may be subjected to a surface modification treatment such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, or dichromate treatment in order to improve the adhesion between the raw fabric layer 2 and the substrate B.

[0039] Materials that can be used for the primer layer 6 include, for example, the materials described below for the design layer 3. Since the primer layer 6 is applied to the back surface of the decorative sheet 1, and considering that the decorative sheet 1 will be wound up in web form, an inorganic filler may be added to the primer layer 6 to avoid blocking and increase adhesion to the adhesive. Examples of inorganic fillers include silica, alumina, magnesia, titanium oxide, and barium sulfate.

[0040] <1.3> Concealing Layer To provide the decorative sheet 1 with concealing properties for the substrate B, for example, a colored sheet is used as the base layer 2, or an opaque concealing layer 8 is provided. The concealing layer 8 can be made of, for example, the same material as that used for the design layer 3, which will be described later. However, since the purpose of the concealing layer 8 is to provide concealing properties, it is preferable to use, for example, an opaque pigment, titanium oxide, iron oxide, or the like, as the pigment. Furthermore, to improve concealing properties, metals such as gold, silver, copper, and aluminum can also be added to the material of the concealing layer 8. Generally, flake-shaped aluminum pieces are often added.

[0041] <1.4> Design Layer The design layer 3 is a layer formed by printing a design onto the base layer 2 using ink. Examples of ink binders include soluble nitrocellulose, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyesters, and modified versions thereof, either alone or in combination. The binder may be aqueous, solvent-based, or emulsion-based, and may be a one-component type or a two-component type incorporating a curing agent. The design layer 3 may be formed by curing a layer formed with a curable ink by exposure to ultraviolet light, electron beams, or the like. The most common method is to use a urethane-based ink that is cured with an isocyanate. The ink used to form the design layer 3 may further contain, in addition to the binder, pigments and colorants such as dyes, extender pigments, solvents, and various additives typically found in inks. Examples of versatile pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolone, cobalt, phthalocyanine, carbon, titanium oxide, iron oxide, and pearl pigments such as mica.

[0042] In addition to applying ink, it is also possible to apply a design to the pattern layer 3 by vapor deposition or sputtering of various metals. In particular, it is preferable that a light stabilizer be added to the ink. This can suppress deterioration of the decorative sheet 1 itself caused by light degradation of the ink, and extend the life of the decorative sheet 1.

[0043] <1.5> Adhesive Layer The adhesive layer 7 is also called a heat-sensitive adhesive layer, an anchor coat layer, or a dry lamination adhesive layer.

[0044] The resin material for the adhesive layer 7 is not particularly limited, and can be appropriately selected from acrylic, polyester, polyurethane, epoxy, and other resin materials. Furthermore, an ethylene-vinyl acetate copolymer resin adhesive can also be used as the resin material for the adhesive layer 7. The coating method can be appropriately selected depending on the viscosity of the adhesive. Generally, gravure coating is used, and the adhesive layer 7 is formed on the upper surface of the design layer 3 by gravure coating, and then the transparent resin layer 4 is laminated. The adhesive layer 7 can be omitted if sufficient adhesive strength can be obtained between the transparent resin layer 4 and the design layer 3.

[0045] <1.6> Transparent Resin Layer An olefin-based resin is preferably used as the resin material for the transparent resin layer 4. Examples of the olefin-based resin include polypropylene, polyethylene, polybutene, and the like, as well as α-olefins (e.g., propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3 Examples of the copolymer include homopolymers of α-olefins such as 9-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, and 12-ethyl-1-tetradecene, or copolymers of two or more of these, as well as copolymers of ethylene or α-olefins with other monomers, such as ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-methyl methacrylate copolymer, ethylene-ethyl methacrylate copolymer, ethylene-butyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-butyl acrylate copolymer.

[0046] Furthermore, in order to improve the surface strength of the decorative sheet 1, it is preferable to use highly crystalline polypropylene as the resin for the transparent resin layer 4. Note that, if necessary, various additives such as heat stabilizers, light stabilizers, antiblocking agents, catalyst scavengers, colorants, light scattering agents, and gloss adjusters can also be added to the transparent resin layer 4. Generally, phenol-based, sulfur-based, phosphorus-based, hydrazine-based, and other heat stabilizers are added, and hindered amine-based, and other light stabilizers are added, in any combination.

[0047] <1.7> Surface Protection Layer The surface protection layer 5 includes a core portion 5A and a plurality of ridge portions 5B each protruding in a ridge shape from one surface of the core portion 5A. These ridge portions 5B form an uneven structure.

[0048] Here, in the decorative sheet 1 according to this embodiment, the term "ridge-like" refers to a convex shape that is linear in plan view. The ridge portions 5B may be curved or linear in plan view, but are preferably curved in view of the fingerprint resistance of the decorative sheet 1. Each ridge portion 5B may be branched or unbranched in plan view. In addition, in the present disclosure, the ridge portions 5B refer to, for example, the portion from the lowest point to the tip of the uneven shape provided on the surface of the surface protective layer 5, and the core portion 5A refers to the portion of the surface protective layer 5 excluding the ridge portions 5B.

[0049] The ridge portions 5B are curved, and at least some of them are adjacent to each other in the width direction, as shown in Fig. 3. At a position where at least some of the ridge portions 5B are adjacent to each other in the width direction, the cross section of the surface protective layer 5 parallel to the width direction and the thickness direction of the surface protective layer 5 has a wave shape, such as a sine wave shape, in the portion where the uneven structure is provided, as shown in Fig. 2.

[0050] The uneven structure of the surface protective layer 5 has a protruding peak height Rpk of less than 3.5 μm. Here, "protruding peak height Rpk" is a surface texture parameter defined in JIS B0671-2:2002. This protruding peak height Rpk is more preferably 3.0 μm or less, and even more preferably 2.8 μm or less. A decorative sheet with this increased protruding peak height Rpk can provide a user with a rough tactile sensation when the user slides their skin over the surface of the surface protective layer, for example, when they slide their finger over the surface of the surface protective layer.

[0051] This protruding peak height Rpk is preferably 0.5 μm or more, more preferably 0.8 μm or more, and even more preferably 1.0 μm or more. A decorative sheet with a small protruding peak height Rpk can generate a large frictional force when a user slides their skin over the surface of the surface protective layer, for example, when they slide their finger over the surface of the surface protective layer.

[0052] The uneven structure of the surface protective layer 5 preferably has an average length RSm of roughness curve elements of 800 μm or less, more preferably 550 μm or less, even more preferably 350 μm or less, even more preferably 320 μm or less, and even more preferably 300 μm or less. Here, the "average length RSm of roughness curve elements" is a surface texture parameter defined in JIS B0601:2013. When a user slides their skin over the surface of the surface protective layer, for example, when they slide their finger over the surface of the surface protective layer, the average length RSm of the roughness curve elements is preferably within the above range in order to provide the user with a smooth feel.

[0053] This average length RSm is preferably 10 μm or more, more preferably 50 μm or more, and even more preferably 80 μm or more. It is difficult to manufacture a structure in which this average length RSm is small and the protruding peak height Rpk is relatively large.

[0054] The absorption spectrum obtained by Fourier infrared spectroscopy of the surface protective layer 5 is 1085 to 1105 cm －１ The maximum value in the wavenumber range of I １０９５ and 1715 to 1735 cm －１ The maximum value in the wavenumber range of I １７２５ Relative to I １０９５ / I １７２５ The low-gloss surface protective layer 5 has a ratio I １０９５ / I １７２５ is within the above range.

[0055] Ratio I １０９５ / I １７２５ is preferably 3.5 or less, and more preferably 2.7 or less. １０９５ / I １７２５ A surface protection layer 5 with a large value tends to have low scratch resistance.

[0056] Here, we will explain the above-mentioned Fourier-type infrared spectroscopy. Infrared light with a wavelength in the range of 2.5 to 25 μm can change the vibration and rotation states of molecules. The energy required to change these vibration and rotation states varies depending on the molecular structure. Infrared spectroscopy is a measurement method that utilizes this to obtain information about the chemical structure and state of a substance.

[0057] In Fourier infrared spectroscopy, measurements are performed, for example, as follows: First, light from a light source is incident obliquely on a semitransparent mirror and split into two beams: transmitted light and reflected light. The beam that passes through the semitransparent mirror is reflected by a fixed mirror and re-enters the semitransparent mirror at an oblique angle. The beam reflected by the semitransparent mirror is reflected by a movable mirror and re-enters the semitransparent mirror at an oblique angle. The beam reflected from the fixed mirror and the beam reflected from the movable mirror and transmitted through the semitransparent mirror are combined to generate an interference wave. While changing the distance from the semitransparent mirror to the movable mirror, this interference wave is irradiated onto a sample, and the intensity of the light transmitted through the sample is measured. The intensity data obtained in this manner is separated into intensities for each wavenumber component by calculation (Fourier transform) to obtain a transmittance spectrum.

[0058] In the Fourier infrared spectroscopic measurement used here, instead of measuring the transmitted light intensity in the above-described Fourier infrared spectroscopic measurement, the reflected light intensity is measured by the attenuated total reflection method (ATR method) described below.

[0059] In Fourier transform infrared spectroscopy using the ATR method, instead of directly incident on the sample, the interference wave is incident on a measurement prism that is in contact with the surface of the sample. The interference wave is incident on the measurement prism so that it is totally reflected at the interface between the prism and the sample. In this way, evanescent waves permeate the region of the sample near the interface, and light of a specific wavenumber component is absorbed by molecules in this region. In addition, in Fourier transform infrared spectroscopy using the ATR method, instead of measuring the intensity of transmitted light, the intensity of reflected light is measured. The intensity data obtained in this way is then separated into intensities for each wavenumber component by calculation (Fourier transform) to obtain an ATR spectrum.

[0060] The penetration depth (depth of penetration) of evanescent waves increases with increasing wavelength. Therefore, the baseline of an ATR spectrum, in which the horizontal axis represents wavelength and the vertical axis represents reflected light intensity (or reflectance), slopes downward to the right. The penetration depth of evanescent waves is also affected by the angle of incidence of the interference wave at the interface and the refractive index of the prism and sample. Therefore, the ATR spectrum is corrected using the reciprocal of the wavelength, for example. By performing such correction, a spectrum with a peak intensity ratio similar to that of the transmittance spectrum can be obtained. Then, by converting this spectrum, an absorption spectrum can be obtained, in which the horizontal axis represents wavenumber and the vertical axis represents absorbance.

[0061] The penetration depth of the evanescent wave is small and can be adjusted by the angle of incidence of the interference wave and the refractive index of the prism. Therefore, Fourier transform infrared spectroscopy using the ATR method can prevent the underlying layer from becoming noise, even if the object to be measured is a thin layer. Furthermore, Fourier transform infrared spectroscopy using the ATR method allows non-destructive measurement as long as the object to be measured is exposed on the surface of the sample.

[0062] As described above, the absorption spectrum obtained by Fourier infrared spectroscopy of the surface protective layer 5 is １０９５ / I １７２５ is within the specified range. －１ The maximum value in the wavenumber range of I １０９５ is a value related to the number of ether bonds contained in the surface protective layer 5. －１ The maximum value in the wavenumber range of I １７２５ is a value related to the number of ester bonds. １０９５ / I １７２５ corresponds to the ratio of the number of ether bonds to the number of functional groups in the acrylate contained in the ionizing radioactive resin in the coating liquid for the surface protective layer, which will be described later.

[0063] The thickness of the surface protective layer 5 is preferably 2 μm or more and 15 μm or less, more preferably 2 μm or more and less than 10 μm, and even more preferably 2 μm or more and less than 8 μm. If the thickness of the surface protective layer 5 is reduced, it becomes difficult to increase the protruding peak height Rpk and the average length RSm. If the thickness of the surface protective layer 5 is increased, the protruding peak height Rpk and the average length RSm tend to increase.

[0064] Here, the thickness of the surface protective layer 5 is the thickness of a layer having the same apparent area and volume as the surface protective layer 5 and a flat surface. The thickness of the surface protective layer 5 is determined, for example, by the following method. First, a cross section parallel to the thickness direction of the surface protective layer 5 and perpendicular to the length direction of the ridge portions 5B is imaged. Next, from this cross-sectional image, the dimension of the surface protective layer 5 in the width direction of the ridge portions 5B and the area of ​​the cross section of the surface protective layer 5 are determined. The thickness of the surface protective layer 5 is a value obtained by dividing this area by the above dimension. Note that when the coating liquid for the surface protective layer described below does not contain a solvent, the thickness of the coating film made of the coating liquid for the surface protective layer is equal to the thickness of the surface protective layer 5.

[0065] The gloss of the surface protective layer 5 is preferably 20.0 or less, more preferably less than 10.0, and even more preferably 8.0 or less. Here, the "gloss" is a value measured at an incident angle of 60 degrees using a gloss meter in accordance with JIS Z8741:1997.

[0066] <2> Manufacturing Method of Decorative Sheet The decorative sheet 1 is manufactured, for example, by the following method. For the sake of brevity, explanations of the design layer 3, transparent resin layer 4, primer layer 6, adhesive layer 7, and hiding layer 8 are omitted here.

[0067] First, a coating film made of a coating liquid for the surface protective layer is formed on one surface of the raw fabric layer 2. This coating film can be formed by various printing methods such as gravure printing, offset printing, screen printing, electrostatic printing, and inkjet printing, or various coating methods such as roll coating, knife coating, microgravure coating, and die coating.

[0068] The coating liquid for the surface protective layer contains an ionizing radiation curable resin. Here, "ionizing radiation" refers to charged particle radiation such as an electron beam. The ionizing radiation curable resin is cured by irradiation with ionizing radiation. The ionizing radiation curable resin can also be cured by irradiation with ultraviolet light. The ionizing radiation curable resin used here is cured by irradiation with light having a wavelength of 200 nm or less, and has a large absorption coefficient for this light.

[0069] In the coating liquid for surface protection layer, when the total solid content thereof is taken as 100 parts by mass, the amount of ionizing radiation curable resin 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. As the ionizing radiation curable resin, known resins such as various monomers and commercially available oligomers can be used, and examples thereof include (meth)acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, and epoxy resins. The ionizing radiation curable resin may be either an aqueous resin or a non-aqueous (organic solvent-based) resin.

[0070] The main component of the ionizing radiation curable resin is preferably an acrylate. Here, the main component of the ionizing radiation curable resin means that the main component is 60 parts by mass or more, based on 100 parts by mass of the total solid content of the ionizing radiation curable resin. The ionizing radiation curable resin preferably contains 70 parts by mass or more of the acrylate, and more preferably 80 parts by mass or more.

[0071] The acrylate is preferably a difunctional or higher acrylate, more preferably a trifunctional or higher acrylate. In order to obtain a surface protective layer 5 having excellent scratch resistance, the acrylate is preferably a trifunctional or higher acrylate. There is no upper limit to the number of functional groups of the acrylate, but according to one example, it is hexafunctional or lower.

[0072] The acrylate preferably contains a repeating unit. This repeating unit is, for example, any one of an ethylene oxide (EO) unit, a propylene oxide (PO) unit, and an ε-caprolactone (CL) unit. The repeating unit is preferably ethylene oxide or propylene oxide. In a tri- or higher functional acrylate containing a repeating unit, the repeating unit may be present between an acryloyl group and a methylol group in an open ring state.

[0073] The number of repetitions of the repeating structure is preferably 3 or more. If an acrylate with a large number of repetitions is used, the cured film is likely to expand in the in-plane direction in the second irradiation step described below, and therefore wrinkles corresponding to the ridge portions 5B are likely to appear on the coating film surface. However, if the number of repetitions is increased, the crosslink density decreases, and the scratch resistance of the surface protective layer decreases.

[0074] The trifunctional acrylate containing a repeating unit is, for example, EO-modified, PO-modified, or CL-modified trimethylolpropane triacrylate, glycerin triacrylate, isocyanurate triacrylate, or pentaerythritol triacrylate. In the trifunctional acrylate containing a repeating unit, the number of repeating units is preferably 3 or more and 30 or less, and more preferably 3 or more and 20 or less.

[0075] The tetrafunctional acrylate containing a repeating unit is, for example, EO-modified, PO-modified, or CL-modified pentaerythritol tetraacrylate. In the tetrafunctional acrylate containing a repeating unit, the number of repeating units is preferably 12 or more, more preferably 12 to 50, and even more preferably 20 to 50.

[0076] The number of repetitions of the repeating structure can be analyzed using MALDI-TOF-MS. Ionizing radiation curable resins may have a molecular weight distribution. When a molecular weight distribution exists, the number of repetitions is determined to be the number of repetitions corresponding to the molecular weight having the strongest peak in the MALDI-TOF-MS mass spectrum.

[0077] As described above, the main component of the ionizing radiation curable resin is preferably an acrylate. The acrylate may be composed of the acrylate described above. Alternatively, the acrylate may be composed of the acrylate described above (hereinafter referred to as a first acrylate) and a second acrylate different from the first acrylate. In this case, the blending ratio of the first acrylate to the second acrylate may be, for example, a mass ratio within a range of 90:10 to 20:80. The second acrylate is, for example, a mono- to hexa-functional acrylate.

[0078] According to one example, the acrylate may be composed of a first acrylate containing a repeating unit and a second acrylate having one to six functionalities. In this example, the repeating unit of the first acrylate is any one of ethylene oxide, propylene oxide, and ε-caprolactone, and the number of repetitions of the repeating unit is 3 or more.

[0079] The second acrylate preferably does not contain a repeating unit. That is, the second acrylate is preferably a mono- to hexa-functional acrylate that does not contain a repeating unit. Specifically, the second acrylate preferably does not contain any of the repeating units of ethylene oxide, propylene oxide, and ε-caprolactone.

[0080] Examples of the second acrylate include trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate.

[0081] The use of the second acrylate in addition to the first acrylate tends to decrease the peak height Rpk and increase the average length RSm of the roughness curve element, thereby increasing the glossiness of the surface protective layer 5 and increasing the thickness variation of the surface protective layer 5.

[0082] The coating liquid for forming a surface protective layer preferably further contains particles. When particles are contained in the coating liquid for forming a surface protective layer, wrinkles can be more uniformly formed on the coating surface in the second irradiation step.

[0083] Examples of the particles that can be used include particles made of organic materials such as polyethylene (PE) wax, polypropylene (PP) wax, and resin beads, and particles made of inorganic materials such as silica, glass, alumina, titania, zirconia, calcium carbonate, and barium sulfate.

[0084] The average particle size (D50) of the particles is preferably 10 μm or less. The average particle size (D50) of the particles is more preferably 1 μm or more and 8 μm or less, and even more preferably 2 μm or more and 6 μm or less. When large particles are used, the particles are likely to fall off from the surface protective layer 5, which may make it difficult to achieve high scratch resistance. When small particles are used, the effect of generating wrinkles uniformly is small.

[0085] Here, the "average particle size (D50)" refers to the median size (D50) measured using a laser diffraction / scattering particle size distribution analyzer. When the coating liquid for the surface protective layer contains particles, the surface protective layer 5 obtained from this coating liquid will also contain particles. The average particle size of the particles contained in the surface protective layer 5 can be determined by observing the cross section of the layer and averaging the particle sizes of multiple particles. The value obtained in this manner is substantially the same as the median size (D50) measured using a laser diffraction / scattering particle size distribution analyzer. Therefore, the above-mentioned range of average particle size can also be interpreted as the range of average particle sizes of the particles contained in the surface protective layer 5.

[0086] The amount of particles added is preferably 0.5 parts by mass or more and 10 parts by mass or less, more preferably 2 parts by mass or more and 8 parts by mass or less, and even more preferably 2 parts by mass or more and 6 parts by mass or less, relative to 100 parts by mass of the ionizing radiation curable resin. When the amount of particles is within the above range, the effect of generating wrinkles uniformly is particularly large.

[0087] The coating liquid for the surface protective layer may further contain a solvent and additives for improving the functionality of the final product, such as an antibacterial agent and an antifungal agent. The coating liquid for the surface protective layer may further contain other additives such as an ultraviolet absorber and a light stabilizer. Examples of ultraviolet absorbers that can be used include benzotriazoles, benzoates, benzophenones, and triazines. Examples of light stabilizers that can be used include hindered amines. Note that, according to the method described herein, a surface protective layer 5 having a low gloss can be formed without a gloss adjuster (matt additive).

[0088] The coating liquid for the surface protective layer preferably further contains a photoinitiator. The photoinitiator is not particularly limited, but examples thereof include benzophenone-based, acetophenone-based, benzoin ether-based, and thioxanthone-based photoinitiators.

[0089] The amount of initiator added is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.25 parts by mass or more and 8 parts by mass or less, and even more preferably 0.5 parts by mass or more and 6 parts by mass or less, relative to 100 parts by mass of the ionizing radiation curable resin. If the amount of initiator is small, the effect of the first irradiation step described below will not be noticeable. If the amount of initiator is too large, the coating film will be completely cured by the first irradiation step, and wrinkles will not be formed in the subsequent second irradiation step.

[0090] After forming a coating film made from the coating liquid for the surface protective layer, a first irradiation step is preferably carried out. In the first irradiation step, the coating film is irradiated with light having a wavelength of approximately 200 nm or more and 400 nm or less (hereinafter referred to as first irradiation light). This semi-cures the coating film. By semi-curing the coating film through the first irradiation step, it is possible to stabilize the mass production of the wrinkled uneven structure (texture) generated by the second irradiation step described below. Alternatively, by appropriately setting the irradiation conditions for the first irradiation step, it is possible to adjust the uneven structure, particularly the depth of the uneven structure.

[0091] The light source used in the first irradiation step can be selected from, for example, a high-pressure mercury lamp, a metal halide lamp, and a single-wavelength LED lamp emitting light with a wavelength of 200 nm or more and 400 nm or less.

[0092] The integrated light amount in the first irradiation step is 2 mJ / cm ２ More than 100mJ / cm ２ It is preferable that the dose is 10 mJ / cm or less. ２ More than 80mJ / cm ２ More preferably, it is 20 mJ / cm or less. ２ More than 60mJ / cm ２ It is more preferable that the cumulative light amount is set to the following: If the cumulative light amount is small, the effect of the first irradiation step described above will not be achieved; if the cumulative light amount is large, the coating film will be completely cured, and wrinkles will not be formed in the subsequent second irradiation step.

[0093] Next, a second irradiation step is carried out. In the second irradiation step, the coating film is irradiated with light having a wavelength of 200 nm or less (hereinafter referred to as second irradiation light). The ionizing radiation curable resin contained in the coating liquid for the surface protective layer has a large absorption coefficient for the second irradiation light. Therefore, the second irradiation light incident on the coating film can only reach a position several tens to several hundreds of nm away from the outermost surface. Therefore, in the second irradiation step, the crosslinking reaction proceeds in the surface region of the coating film, forming an extremely thin cured film, while the crosslinking reaction does not proceed in other regions, leaving the coating film semi-cured.

[0094] The coating film after the second irradiation step has wrinkles on its surface corresponding to the ridge portions 5 B. The present inventors believe that the reason why wrinkles are formed on the coating film surface by the second irradiation step is as follows.

[0095] As described above, the second exposure light can only reach a position several tens to several hundreds of nanometers from the outermost surface of the coating film. That is, the crosslinking reaction of the ionizing radiation curable resin due to irradiation with the second exposure light occurs only on the surface of the coating film. When irradiated with the second exposure light, the monomers and the like present on the surface of the coating film are crosslinked via the functional groups they possess to form a cured film, but not all of these functional groups are used to crosslink the monomers present on the surface of the coating film. That is, uncrosslinked functional groups may remain in the cured film.

[0096] The second irradiation light does not reach the monomers present at positions away from the surface of the coating film, so the crosslinking reaction does not occur there. However, some of the monomers present at positions away from the surface of the coating film migrate to the cured film and undergo crosslinking reaction there. In this way, the number of molecules involved in the crosslinking reaction increases.

[0097] As the number of molecules involved in the crosslinking reaction at the coating surface increases, the volume of the cured film increases. Because the crosslinking reaction occurs only at the surface of the coating, the cured film cannot increase in volume in the thickness direction, but expands in the in-plane direction. As a result, wrinkles appear on the surface of the coating.

[0098] The second irradiation light can be extracted from excimer VUV (Vacuum Ultra Violet) light. Excimer VUV light can be generated from a lamp using a rare gas or a rare gas halide compound. When high-energy electrons are externally applied to a lamp containing a rare gas or a rare gas halide compound, a large number of discharge plasmas (dielectric barrier discharges) are generated. This plasma discharge excites atoms of the discharge gas (rare gas), which momentarily transition to an excimer state. When returning from this excimer state to the ground state, light is emitted in a wavelength range specific to that excimer.

[0099] The gas used in the excimer lamp may be any conventional gas that emits light of 200 nm or less. Examples of the gas include rare gases such as Xe, Ar, and Kr, and mixtures of rare gases such as ArBr and ArF with halogen gases. The wavelength (center wavelength) of excimer lamps varies depending on the gas, and examples include wavelengths of approximately 172 nm (Xe), approximately 126 nm (Ar), approximately 146 nm (Kr), approximately 165 nm (ArBr), and approximately 193 nm (ArF).

[0100] Considering the magnitude of photon energy and the difference between wavelength and bond energy of organic matter, it is preferable to use a xenon lamp that emits excimer light with a central wavelength of 172 nm as the light source. Also, considering the cost of maintaining the equipment and the availability of materials, it is preferable to use a xenon lamp as the light source.

[0101] The second irradiation step is carried out in an atmosphere with a low oxygen concentration. Oxygen has a high absorption coefficient for light of 200 nm or less. Therefore, the second irradiation step is preferably carried out in, for example, a nitrogen gas atmosphere. The oxygen concentration in the gas phase in the second irradiation step, i.e., the residual oxygen concentration in the reaction atmosphere, is preferably 2000 ppm or less, and more preferably 1000 ppm or less.

[0102] Furthermore, oxygen in the atmosphere inhibits radical polymerization. Therefore, the residual oxygen concentration in the reaction atmosphere affects the formation of wrinkles on the coating surface. Therefore, changing the residual oxygen concentration in the reaction atmosphere can also change the surface properties of the surface protective layer 5.

[0103] The cumulative light amount in the second irradiation step is 0.5 mJ / cm ２ More than 200mJ / cm ２ It is preferable that the dose is 1 mJ / cm or less. ２ More than 100mJ / cm ２ More preferably, it is 3 mJ / cm or less. ２ More than 50mJ / cm ２ It is more preferable that the integrated light amount is set to the following: If the integrated light amount is small, the expansion of the cured film in the in-plane direction is small, whereas if the integrated light amount is large, the surface condition of the coating film is deteriorated.

[0104] After the second irradiation step, the third irradiation step is carried out. In the third irradiation step, the coating film is irradiated with a third radiation or irradiation light to cure the entire coating film. In this way, the surface protective layer 5 is obtained.

[0105] The third radiation or irradiation light is ionizing radiation such as an electron beam, or ultraviolet light having a longer wavelength than the second irradiation light.

[0106] When the third radiation or irradiation light is ultraviolet light, the integrated light amount is 10 mJ / cm ２ More than 500mJ / cm ２ It is preferable that the dose is 50 mJ / cm or less. ２ More than 400mJ / cm ２ More preferably, it is 100 mJ / cm or less. ２ More than 300mJ / cm ２ It is more preferable that:

[0107] <3> Effects The decorative sheet 1 described with reference to Figures 1 to 3 has the above-mentioned surface properties in the surface protective layer 5. Such a decorative sheet 1 gives the user a smooth feel when the user slides their skin over the surface of the surface protective layer 5, for example, when they slide their finger over the surface of the surface protective layer 5. In other words, this decorative sheet 1 allows the user to slide their finger or the like with little frictional force, without the user being aware of the presence of large irregularities.

[0108] The decorative sheet 1, which provides a smooth feel to the user, is suitable for use in applications where it frequently comes into contact with the user's skin or where the user's skin is in contact with the sheet for long periods of time, such as furniture. Articles using the decorative sheet 1 do not cause discomfort to the user when they come into contact with the user's skin.

[0109] The surface protective layer 5 of the decorative sheet 1 has the above-described surface properties, and therefore achieves a low gloss even without containing a gloss adjuster (matt additive). Gloss adjusters reduce the oil repellency of layers formed from resin materials, making surface protective layers containing gloss adjusters susceptible to fingerprints. Surface protective layers 5 that do not contain gloss adjusters are less likely to absorb oil and therefore less likely to be marked with fingerprints. Furthermore, surface protective layers 5 with excellent oil repellency are less likely to develop oil stains or adsorb contaminants. Furthermore, surface protective layers 5 that do not contain gloss adjusters do not lose gloss adjuster particles when their surface is scratched, and therefore decorative sheets 1 containing such surface protective layers 5 are less likely to develop gloss changes or scratches.

[0110] The reason why the surface protection layer 5 having the above-described surface properties can be obtained by the above-described method is as follows.

[0111] Oxygen in the gas phase not only absorbs short-wavelength ultraviolet rays but also inhibits radical polymerization. The effect of oxygen contained in the gas phase on radical polymerization is greatest in the portion of the coating film made of an ionizing radiation-curable resin adjacent to the gas phase, and decreases as the distance from the coating film surface increases. Therefore, by changing the oxygen concentration in the gas phase in the second irradiation step, the relationship between the distance from the coating film surface and the progress of the crosslinking reaction can be changed.

[0112] If this relationship changes, the thickness of the cured film formed on the surface of the coating film by the second irradiation step and the degree of in-plane expansion of the cured film according to the progress of the crosslinking reaction will change. The thickness of the cured film and the degree of in-plane expansion of the cured film will also be affected by the integrated light amount in the second irradiation step. The thickness of the cured film and the degree of in-plane expansion of the cured film will then affect the surface properties of the surface protective layer. Furthermore, the thickness of the coating film will also affect the formation of wrinkles.

[0113] Therefore, for example, by appropriately setting the composition of the ionizing radiation curable resin, the thickness of the coating film, the oxygen concentration in the gas phase in the second irradiation step, and the integrated light amount in the second irradiation step, it is possible to obtain a surface protection layer having the desired surface properties.

[0114] The following describes examples of the present invention.

[0115] 1 to 3 was produced by the following method. In this example, the transparent resin layer 4, primer layer 6, adhesive layer 7, and hiding layer 8 were omitted.

[0116] First, the basis weight is 50 g / m ２ An impregnated paper (GFR-506, manufactured by Kojin Co., Ltd.) was prepared as the raw fabric layer 2. On one side of the raw fabric layer 2, a design layer 3 was formed using an oil-based nitrocellulose resin gravure printing ink (PCNT (PCRNT) various colors, manufactured by Toyo Ink Co., Ltd.).

[0117] Next, a coating liquid for a surface protective layer was applied onto the design layer 3. The coating liquid for the surface protective layer was a mixture of the following ionizing radiation curable resin with the following particles and initiator: Ionizing radiation curable resin Type: ethylene glycol diacrylate (9 moles of EO added) Product name: Light Acrylate 9EG-A (manufactured by Kyoeisha Chemical Co., Ltd.) Blend: 100 parts by mass Particles Product name: Sylysia 250N (manufactured by Fuji Silysia Chemical Ltd.) Particle size: 5 μm Blend: 2 parts by mass Initiator Product name: OMNIRAD 184 (manufactured by IGM Resins) Blend: 1 part by mass A coating film made of the coating liquid for the surface protective layer was formed to a thickness of 5 μm.

[0118] Thereafter, a first irradiation step was carried out. Specifically, a high-pressure mercury lamp was used to irradiate ultraviolet light having a dominant wavelength of 365 nm onto the surface of the coating film made of the coating liquid for surface protective layer in the atmosphere, with the ultraviolet light being irradiated at an integrated light intensity of 100 mJ / cm. ２ This caused the coating film to be semi-cured.

[0119] Next, the second irradiation step was carried out. Specifically, under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for surface protective layer using a Xe excimer lamp at an integrated light intensity of 50 mJ / cm. ２ This caused wrinkles to form on the surface of the coating film.

[0120] Finally, the third irradiation step was carried out. Specifically, the coating film was irradiated with ionizing radiation to cure the entire film, thereby forming a surface protective layer 5. In this manner, a decorative sheet 1 was obtained.

[0121] <Example 2> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used: Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 6 moles added) Product name: Miramer M3160 (manufactured by Miwon Co., Ltd.) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 50 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm. ２ The irradiation was carried out so that

[0122] <Example 3> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used: Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 15 moles added) Product name: SR9035 (manufactured by Sartomer) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 50 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm.２ The irradiation was carried out so that

[0123] <Example 4> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used: Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (3 EO moles added) Product name: Miramer M3130 (manufactured by Miwon Co., Ltd.) The second irradiation step involved irradiating the surface of the coating film made of the surface protective layer coating liquid with ultraviolet light at a wavelength of 172 nm using a Xe excimer lamp at an integrated light intensity of 100 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm. ２ The irradiation was carried out so that

[0124] <Example 5> Decorative sheet 1 was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the following ionizing radiation curable resin was used: Ionizing radiation curable resin Type: Trimethylolpropane PO modified triacrylate (PO 6 moles added) Product name: NK Ester A-TMPT-6PO (manufactured by Shin-Nakamura Chemical Co., Ltd.) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 50 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm. ２ The irradiation was carried out so that

[0125] <Example 6> Decorative sheet 1 was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the following ionizing radiation curable resin was used: Ionizing radiation curable resin Type: Caprolactone-modified tris-(2-acryloxyethyl) isocyanurate (caprolactone (CL) 3 moles added) Product name: NK Ester A-9300-3CL (manufactured by Shin-Nakamura Chemical Co., Ltd.) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 100 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm. ２ The irradiation was carried out so that

[0126] <Example 7> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. A coating film made of the coating liquid for surface protection layer was formed to a thickness of 1 μm. Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 6 moles added) Product name: Miramer M3160 (manufactured by Miwon Co., Ltd.) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for surface protection layer using a Xe excimer lamp at atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm, with an integrated light intensity of 10 mJ / cm. ２ The irradiation was carried out so that

[0127] <Example 8> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. A coating film made of the coating liquid for surface protection layer was formed to a thickness of 2 μm. Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 6 moles added) Product name: Miramer M3160 (manufactured by Miwon Co., Ltd.) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for surface protection layer using a Xe excimer lamp at atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm, with an integrated light intensity of 10 mJ / cm. ２ The irradiation was carried out so that

[0128] <Example 9> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. A coating film made of the coating liquid for surface protection layer was formed to a thickness of 9 μm. Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (3 EO moles added) Product name: Miramer M3130 (manufactured by Miwon Co., Ltd.) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for surface protection layer using a Xe excimer lamp at atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm, with an integrated light intensity of 150 mJ / cm. ２ The irradiation was carried out so that

[0129] <Example 10> Decorative sheet 1 was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the following ionizing radiation curable resin was used: Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (35 moles of EO added) Product name: NK Ester ATM-35E (manufactured by Shin-Nakamura Chemical Co., Ltd.) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 50 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm. ２ The irradiation was carried out so that

[0130] <Example 11> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (50 moles of EO added) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 50 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm. ２ The irradiation was carried out so that

[0131] <Example 12> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (20 moles of EO added) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 100 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm. ２ The irradiation was carried out so that

[0132] <Example 13> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used: Ionizing radiation curable resin Type: propoxylated pentaerythritol tetraacrylate (PO 35 moles added) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 50 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm. ２ The irradiation was carried out so that

[0133] <Example 14> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. Ionizing radiation curable resin Type: Caprolactone-modified pentaerythritol tetraacrylate (20 moles of CL added) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for surface protection layer using a Xe excimer lamp at an integrated light intensity of 100 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm. ２ The irradiation was carried out so that

[0134] <Example 15> Decorative sheet 1 was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the following ionizing radiation curable resin was used. A coating film made from the coating liquid for surface protection layer was formed to a thickness of 1 μm. - Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (35 moles of EO added) Product name: NK Ester ATM-35E (manufactured by Shin-Nakamura Chemical Co., Ltd.) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated to the surface of the coating film made from the coating liquid for surface protection layer using a Xe excimer lamp at atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm, with an integrated light intensity of 10 mJ / cm. ２ The irradiation was carried out so that

[0135] <Example 16> Decorative sheet 1 was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the following ionizing radiation curable resin was used. A coating film made from the coating liquid for surface protection layer was formed to a thickness of 2 μm. - Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (35 moles of EO added) Product name: NK Ester ATM-35E (manufactured by Shin-Nakamura Chemical Co., Ltd.) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated to the surface of the coating film made from the coating liquid for surface protection layer using a Xe excimer lamp at atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm, with an integrated light intensity of 10 mJ / cm. ２ The irradiation was carried out so that

[0136] <Example 17> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. A coating film made of the coating liquid for surface protective layer was formed to a thickness of 9 μm. Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (35 moles of EO added) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for surface protective layer using a Xe excimer lamp at an integrated light intensity of 150 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm. ２ The irradiation was carried out so that

[0137] <Example 18> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resins were used. Ionizing radiation curable resin 1 Trimethylolpropane EO-modified triacrylate (EO 6 moles added) Product name: Miramer M3160 (manufactured by Miwon Co., Ltd.) Blend: 60 parts by mass Ionizing radiation curable resin 2 Type: Dipentaerythritol hexaacrylate Product name: Miramer M600 (manufactured by Miwon Co., Ltd.) Blend: 40 parts by mass Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for surface protection layer using a Xe excimer lamp at an integrated light intensity of 10 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm. ２ The irradiation was carried out so that

[0138] <Example 19> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resins were used. Ionizing radiation curable resin 1 Trimethylolpropane EO-modified triacrylate (EO 6 moles added) Product name: Miramer M3160 (manufactured by Miwon Co., Ltd.) Blend: 40 parts by mass Ionizing radiation curable resin 2 Type: Dipentaerythritol hexaacrylate Product name: Miramer M600 (manufactured by Miwon Co., Ltd.) Blend: 60 parts by mass Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for surface protective layer using a Xe excimer lamp at an integrated light intensity of 10 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm. ２ The irradiation was carried out so that

[0139] <Example 20> Decorative sheet 1 was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resins were used. A coating film made from the coating liquid for surface protection layer was formed to a thickness of 14 μm. - Ionizing radiation curable resin 1 Trimethylolpropane EO-modified triacrylate (EO 6 moles added) Product name: Miramer M3160 (manufactured by Miwon Co., Ltd.) Blend: 40 parts by mass - Ionizing radiation curable resin 2 Type: Dipentaerythritol hexaacrylate Product name: Miramer M600 (manufactured by Miwon Co., Ltd.) Blend: 60 parts by mass Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated to the surface of the coating film made from the coating liquid for surface protection layer using a Xe excimer lamp at an integrated light intensity of 100 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm. ２ The irradiation was carried out so that

[0140] Comparative Example 1 A decorative sheet was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the coating liquid for the surface protective layer was a mixture of the following ionizing radiation curable resin and the following particles. Ionizing radiation curable resin Type: trimethylolpropane EO-modified triacrylate (6 EO moles added) Product name: Miramer M3160 (manufactured by Miwon) Blend: 100 parts by mass Particles Product name: Sylysia 250N (manufactured by Fuji Silysia Chemical Ltd.) Particle size: 5 μm Blend: 15 parts by mass The first and second irradiation steps were not carried out, and the coating film made of the coating liquid for the surface protective layer was cured only by the third irradiation step.

[0141] Comparative Example 2 A decorative sheet was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the coating liquid for the surface protective layer was a mixture of the following ionizing radiation curable resin and the following particles: Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (35 moles of EO added) Product name: NK Ester ATM-35E (manufactured by Shin-Nakamura Chemical Co., Ltd.) Blend: 100 parts by mass Particles Product name: Sylysia 250N (manufactured by Fuji Silysia Chemical Ltd.) Particle size: 5 μm Blend: 15 parts by mass The first and second irradiation steps were not carried out, and the coating film made of the coating liquid for the surface protective layer was cured only by the third irradiation step.

[0142] Comparative Example 3 A decorative sheet was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. A coating film made of the coating liquid for surface protection layer was formed to a thickness of 10 μm. Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (6 EO moles added) Product name: Miramer M3160 (manufactured by Miwon Co., Ltd.) Then, in the second irradiation step, ultraviolet light with a wavelength of 172 nm was irradiated to the surface of the coating film made of the coating liquid for surface protection layer using a Xe excimer lamp at atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm, with an integrated light intensity of 150 mJ / cm. ２ The irradiation was carried out so that

[0143] Comparative Example 4 A decorative sheet was produced in the same manner as in Example 1, except for the following points. That is, in this example, the following ionizing radiation curable resin was used. A coating film made from the coating liquid for surface protection layer was formed to a thickness of 10 μm. Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (35 moles of EO added) Product name: NK Ester ATM-35E (manufactured by Shin-Nakamura Chemical Co., Ltd.) Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated to the surface of the coating film made from the coating liquid for surface protection layer using a Xe excimer lamp at atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm, with an integrated light intensity of 150 mJ / cm. ２ The irradiation was carried out so that

[0144] Comparative Example 5 Decorative sheet 1 was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the following ionizing radiation curable resins were used: Ionizing radiation curable resin 1 Type: Trimethylolpropane EO-modified triacrylate (3 mols of EO added) Product name: Miramer M3130 (manufactured by Miwon Co., Ltd.) Blend: 20 parts by mass Ionizing radiation curable resin 2 Type: Dipentaerythritol hexaacrylate Product name: Miramer M600 (manufactured by Miwon Co., Ltd.) Blend: 80 parts by mass Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 100 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm. ２ The irradiation was carried out so that

[0145] Comparative Example 6 Decorative sheet 1 was produced in the same manner as in Example 1, with the following exceptions. That is, in this example, the following ionizing radiation curable resins were used. Ionizing radiation curable resin 1 Type: Ethoxylated pentaerythritol tetraacrylate (4 mols of EO added) Product name: NK Ester ATM-4E (manufactured by Shin-Nakamura Chemical Co., Ltd.) Blend: 80 parts by mass Ionizing radiation curable resin 2 Type: Dipentaerythritol hexaacrylate Product name: Miramer M600 (manufactured by Miwon Co., Ltd.) Blend: 20 parts by mass Then, in the second irradiation step, ultraviolet light having a wavelength of 172 nm was irradiated onto the surface of the coating film made of the coating liquid for the surface protective layer using a Xe excimer lamp at an integrated light intensity of 100 mJ / cm under atmospheric pressure in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm. ２ The irradiation was carried out so that

[0146] <Evaluation> Each of the decorative sheets described above was subjected to the following evaluations.

[0147] (1) Glossiness The glossiness was measured at 60 degrees using a Rhopoint IQ (manufactured by Konica Minolta, Inc.) The "60 degree glossiness value" in Tables 1 to 4 below represents this 60 degree glossiness.

[0148] (2) Skin Feel Skin feel was evaluated using the following method. First, preliminary preparations were made to ensure that the evaluation criteria were consistent among the evaluators. Specifically, 10 standard test pieces with different surface textures were prepared. Next, each of the 20 evaluators was asked to run their finger over the surface of the standard test piece while blindfolded, and then classify the tactile sensation into the following five groups. Group 1: Almost no unevenness was felt, and the frictional force was felt to be small. Group 2: The presence of small unevenness was felt, or the frictional force was felt to be somewhat large. Group 3: The tactile sensation was intermediate between the tactile sensations of Groups 1 and 2.

[0149] Group 4: Felt the presence of large irregularities. Group 5: Felt the presence of large irregularities and felt a large frictional force. The above procedure was repeated until the evaluations by each evaluator were consistent for three or more consecutive evaluations, and the evaluation results between the evaluators were consistent for three consecutive evaluations.

[0150] Next, for each of the decorative sheets, each of the evaluators was asked to run their fingers over the surface of the surface protective layer while blindfolded, and then classify the tactile sensation into one of the five groups. This procedure was repeated until the evaluations by each evaluator were consistent for three or more consecutive evaluations, and the evaluation results between the evaluators were consistent for three or more consecutive evaluations. From these results, the skin sensation was evaluated according to the following criteria: AAA (smooth): Group 1 AA (smooth): Group 3 A (smooth): Group 2 B (rough or smooth): Group 4 or 5

[0151] (3) Fingerprint Resistance To evaluate fingerprint resistance, a fingerprint wiping property evaluation was performed. Specifically, first, the 60-degree glossiness of the surface of each decorative sheet was measured, and this 60-degree glossiness was defined as the initial glossiness. Next, a fingerprint resistance evaluation liquid was applied to the surface protective layer, and the fingerprint resistance evaluation liquid applied to the decorative sheet surface was wiped off. Here, a higher fatty acid was used as the fingerprint resistance evaluation liquid. Thereafter, the 60-degree glossiness of the portion from which the fingerprint resistance evaluation liquid had been wiped off was measured, and this 60-degree glossiness was defined as the glossiness after wiping.

[0152] The fingerprint wiping rate was calculated from the following formula: Fingerprint wiping rate (%)=(glossiness after wiping / initial glossiness)×100 The evaluation criteria were as follows.

[0153] AA: 70% or more and less than 250% A: 50% or more and less than 70%, or 250% or more and less than 300% B: Less than 50%, or 300% or more

[0154] (4) Stain Resistance To evaluate stain resistance, the Stain A test specified in the Japanese Agricultural Standards (JAS) was carried out. That is, 10 mm wide lines were drawn on the surface protective layer of each decorative sheet using blue ink, black quick-drying ink, and red crayon, and the sheets were left for 4 hours. Thereafter, the blue ink, black quick-drying ink, and red crayon lines were wiped off with a cloth soaked in ethanol.

[0155] The evaluation criteria were as follows: AA: Lines of each color could be easily wiped off. A: Part of the lines of each color could be wiped off, but some stains remained. B: Lines of each color could not be wiped off.

[0156] (5) Scratch Resistance Each decorative sheet was attached to wood substrate B using a urethane adhesive. A steel wool rubbing test was then conducted to evaluate scratch resistance. Specifically, the decorative sheet was rubbed back and forth 20 times with steel wool while applying a load of 100 g, and the occurrence of scratches on the surface of the decorative sheet and any changes in gloss were visually confirmed.

[0157] The evaluation criteria were as follows: AA: No scratches or changes in gloss occurred on the surface. A: Minor scratches or changes in gloss occurred on the surface. B: Significant scratches or changes in gloss occurred on the surface.

[0158] (6) Uniformity of Surface Condition To evaluate mass production stability, the uniformity of the surface condition regarding the occurrence of irregularities was visually confirmed. The evaluation criteria were as follows: AA: The surface condition is uniform. A: The surface condition is roughly uniform. B: The surface condition is non-uniform.

[0159] (7) Fourier-type infrared spectroscopy For Fourier-type infrared spectroscopy, a Fourier-type infrared spectrometer (FT / IR-6300) manufactured by JASCO Corporation and a single-reflection (incident angle 45°) ATR unit (ATR PRO470-H) using a diamond prism with a sample contact area of ​​2 mmφ were used.

[0160] The measurement conditions were as follows: Measurement wave number range: 4000 cm －１ From 400cm －１ Resolution: 4.0cm －１Light source: Standard light source Detector: TGS Sample chamber: Standard Sensitivity (gain): 32x Aperture diameter: 7.1 mm Interferometer measurement (scan speed): 2 mm / sec Filter: 10000 Hz Beam splitter: Ge / KBr Apodization function: Cosine Zero filling: on Then, the optical system was substituted with a nitrogen atmosphere, and an absorption spectrum was obtained after 160 cumulative measurements. Before measuring the absorption spectrum of the sample, a background measurement was performed under the same conditions as the measurement for the sample, except that nothing was brought into contact with the diamond crystal and the cumulative measurement was 320.

[0161] The obtained absorption spectrum was subjected to ATR correction by the "penetration depth" method using Spectra Manager Version 2 manufactured by JASCO Corporation. １０９５ / I １７２５ The value was calculated.

[0162] The results are shown in Tables 1 to 4 below.

[0163]

[0164]

[0165]

[0166]

[0167] As shown in Tables 1 to 3, the decorative sheets according to Examples 1 to 20 provided evaluators with a smooth feel. Furthermore, the decorative sheets according to Examples 1 to 20 had low gloss and excellent fingerprint resistance and stain resistance. Furthermore, the decorative sheets according to Examples 1 to 20 also had excellent scratch resistance.

[0168] In contrast, the decorative sheets according to Comparative Examples 1 and 2 did not provide the evaluators with a smooth feel to the touch, and were poor in all of fingerprint resistance, stain resistance, and scratch resistance, as shown in Table 4. The decorative sheets according to Comparative Examples 3 and 4 were low gloss and excellent in fingerprint resistance, stain resistance, and scratch resistance, but did not provide the evaluators with a smooth feel to the touch. The decorative sheets according to Comparative Examples 5 and 6 provided the evaluators with a smooth feel to the touch, and were excellent in fingerprint resistance, stain resistance, and scratch resistance, but did not achieve low gloss.

[0169] 1...decorative sheet, 2...base layer, 3...pattern layer, 4...transparent resin layer, 5...surface protection layer, 6...primer layer, 7...adhesive layer, 8...hiding layer, 11...decorative material, B...base material.

Claims

1. A base fabric layer and a surface protective layer provided on one surface of the base fabric layer, a concave-convex structure including a plurality of ridge-like portions each protruding in a ridge shape is provided on a surface of the surface protection layer; The uneven structure of the surface protective layer has a protruding peak height Rpk of less than 3.5 μm, The absorption spectrum obtained by Fourier infrared spectroscopy of the surface protective layer has a wavelength of 1085 to 1105 cm －１ Maximum value in the wave number range I １０９５ and 1715 to 1735 cm －１ Maximum value in the wave number range I １７２５ Comparison with I １０９５ / I １７２５ A decorative sheet having a value of 0.65 or more.

2. The ratio I １０９５ / I １７２５ 2. The decorative sheet according to claim 1, wherein the .lambda. is 3.5 or less.

3. 2. The decorative sheet according to claim 1, wherein said protruding peak height Rpk is 0.5 μm or more.

4. 2. The decorative sheet according to claim 1, wherein the uneven structure of the surface protective layer has a mean length RSm of roughness curve elements of 800 μm or less.

5. The decorative sheet according to claim 4, wherein said average length RSm is 10 µm or more.

6. 2. The decorative sheet according to claim 1, wherein the thickness of said surface protective layer is from 2 μm to 15 μm.

7. 2. The decorative sheet according to claim 1, wherein the surface protective layer has a glossiness of 20.0 or less.

8. The decorative sheet according to claim 1, wherein at least a portion of the plurality of ridge portions are adjacent to each other in the width direction, and at a position where at least a portion of the plurality of ridge portions are adjacent to each other in the width direction, a cross section parallel to the width direction and the thickness direction of the surface protection layer has a sinusoidal shape in the portion where the uneven structure is provided.

9. The decorative sheet according to claim 1 , wherein the surface protective layer contains a cured product of an ionizing radiation curable resin.

10. 10. The decorative sheet according to claim 9, wherein the ionizing radiation curable resin is an acrylate containing a repeating structure as a main component, the repeating structure is any one of ethylene oxide, propylene oxide, and ε-caprolactone, and the number of repetitions of the repeating structure is 3 or more.

11. The ionizing radiation curable resin contains an acrylate as a main component, The acrylate is a first acrylate including a repeating structure, the repeating structure being any one of ethylene oxide, propylene oxide, and ε-caprolactone, and the number of repetitions of the repeating structure being 3 or more; a monofunctional to hexafunctional second acrylate; The decorative sheet according to claim 9, which is composed of

12. A decorative material comprising the decorative sheet according to any one of claims 1 to 11 and a substrate to which the decorative sheet is attached.