decorative sheet

Abstract

We provide a decorative sheet that offers excellent scratch resistance and a smooth, moist texture. [Solution] The decorative sheet 1 has an uneven structure including ridges on the surface of the surface protective layer 5, and when the power spectrum image obtained by performing a two-dimensional fast Fourier transform on the surface shape image is defined as follows: the average value of brightness in the spatial frequency range of 95 to 105 cycles / mm is P_100, the average value of brightness in the spatial frequency range of 195 to 205 cycles / mm is P_200, and the average value of brightness in the spatial frequency range of 695 to 705 cycles / mm is P_700, and the ratio of the difference between P_100 and P_700 to the difference between P_200 and P_700 is Rt_P, the average value of Rt_P is in the range of 1.57 to 1.82, the surface protective layer contains 100 parts by mass of cured resin and 3 to 11 parts by mass of particles with an average particle size of 3 μm or more, has a thickness of 2 to 18 μm, and has a glossiness of less than 10.

Description

[Technical Field]

[0001] This invention relates to a decorative sheet. [Background technology]

[0002] Decorative sheets are used, for example, for the purpose of surface decoration of interior and exterior materials such as doors, furniture, joinery, and flooring, that is, to provide aesthetic appeal and durability to these materials. Decorative sheets are generally widely used as decorative panels that are attached to the surface of substrates such as wood, wood fiberboard, metal plates, non-combustible boards, paper substrates, and resin substrates using adhesives.

[0003] Design appeal is achieved, for example, by creating patterns such as wood grain or stone patterns using various printing methods. Plain, unpatterned decorative sheets are sometimes preferred. The presence or absence of patterns, and the type of pattern chosen, varies depending on the application and personal preference.

[0004] The glossiness of the surface is also an important aspect of the design of decorative sheets. Depending on the application and preference, a variety of decorative sheets can be selected, from highly glossy, mirror-like finishes to low-gloss finishes that show no reflections at all.

[0005] Furthermore, as mentioned above, alongside the provision of aesthetic appeal, durability is another important function of decorative sheets. Durability is a comprehensive evaluation of scratch resistance, stain resistance, and whether these properties are maintained over a long period of time. While the requirements vary depending on the environment and circumstances in which the decorative sheet is used, there is always a demand for decorative sheets with high performance.

[0006] To enhance durability, it is common practice to form a surface protective layer on the outermost surface of the decorative sheet. Furthermore, to adjust the gloss level, particularly to achieve a low gloss, it is common practice to add a gloss adjuster (matte additive) to the surface protective layer.

[0007] Furthermore, since the decorative sheet is generally subjected to processing such as cutting and bending to form decorative materials such as decorative boards, it is preferable that the decorative sheet has processability that can withstand these processes.

[0008] Thus, as a decorative sheet in which design properties (low gloss), scratch resistance, and stain resistance are considered, for example, there is the decorative sheet described in Patent Document 1.

Prior Art Documents

Patent Documents

[0009]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0010] An object of the present invention is to provide a decorative sheet that is excellent in scratch resistance and gives a moist touch.

Means for Solving the Problems

[0011] According to one aspect of the present invention, there is provided a base fabric layer and a surface protection layer provided on one surface of the base fabric layer, and an uneven structure including a plurality of ridge-shaped portions each protruding in a ridge shape is provided on the surface of the surface protection layer. Regarding the power spectrum image obtained by two-dimensional fast Fourier transform of the surface shape image of the uneven structure, the average value of the luminance in the section where the spatial frequency is 95 cycles / mm or more and 105 cycles / mm or less is defined as P_100, the average value of the luminance in the section where the spatial frequency is 195 cycles / mm or more and 205 cycles / mm or less is defined as P_200, and the average value of the luminance in the section where the spatial frequency is 695 cycles / mm or more and 705 cycles / mm or less is defined as P_700. When the ratio of the difference between P_100 and P_700 to the difference between P_200 and P_700 is defined as Rt_P, the average value of Rt_P is within the range of 1.57 to 1.82. The surface protection layer includes a cured product of a resin and particles. The particles have an average particle diameter of 3 μm or more and are included in the surface protection layer in an amount of 3 parts by mass or more and 11 parts by mass or less with respect to 100 parts by mass of the resin. The surface protection layer has a thickness of 2 μm or more and 18 μm or less, and a decorative sheet is provided in which the glossiness of the surface protection layer is less than 10.

[0012] According to another aspect of the present invention, there is provided a decorative sheet according to the above aspect, in which the average particle diameter of the particles is 3 μm or more and 11 μm or less.

[0013] According to still another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, in which the resin is a radiation-curable resin.

[0014] According to still another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, in which the resin is an acrylate.

[0015] According to still another aspect of the present invention, there is provided a decorative sheet according to any one of the above aspects, in which the resin is a trifunctional acrylate including a repeating structure, and the number of repetitions of the repeating structure is 3 or more and 20 or less.

[0016] According to yet another aspect of the present invention, a decorative sheet is provided relating to any of the above aspects, wherein the resin is a tetrafunctional acrylate having a repeating structure, and the number of repetitions of the repeating structure is 20 or more and 35 or less.

[0017] According to yet another aspect of the present invention, a decorative sheet is provided which further comprises a pattern layer between the base material layer and the surface protective layer, according to any of the above aspects.

[0018] In yet another aspect of the present invention, a decorative material is provided comprising a decorative sheet relating to any of the above aspects and a substrate to which the decorative sheet is attached. [Effects of the Invention]

[0019] According to the present invention, it is possible to provide a decorative sheet that has excellent scratch resistance and a moist texture. [Brief explanation of the drawing]

[0020] [Figure 1] Figure 1 is a cross-sectional view of a decorative material including a decorative sheet according to one embodiment of the present invention. [Figure 2] Figure 2 is a cross-sectional view of the surface protective layer included in the decorative sheet shown in Figure 1. [Figure 3] Figure 3 is a microscopic image of the surface protective layer contained in a decorative sheet according to an example of the present invention. [Modes for carrying out the invention]

[0021] Embodiments of the present invention will be described below with reference to the drawings. The embodiments described below are more specific to any of the above aspects. The matters described below can be incorporated into each of the above aspects, individually or in combination.

[0022] Furthermore, the embodiments shown below illustrate configurations for realizing the technical concept of the present invention, and the technical concept of the present invention is not limited by the material, shape, and structure of the components described below. Various modifications can be made to the technical concept of the present invention within the technical scope defined by the claims described in the claims.

[0023] Elements with similar or identical functions are given the same reference numerals in the drawings referenced below, and redundant explanations are omitted. Furthermore, the drawings are schematic, and the relationships between dimensions in one direction and those in another, and the relationships between the dimensions of one component and those of other components, may differ from reality.

[0024] <1> Decorative materials and decorative sheets Figure 1 is a cross-sectional view of a decorative material containing a decorative sheet according to one embodiment of the present invention. Figure 2 is a cross-sectional view of the surface protective layer contained in the decorative sheet of Figure 1. Figure 3 is a micrograph of the surface protective layer contained in a decorative sheet according to an example of the present invention.

[0025] Note that the cross-section shown in Figure 2 is a cross-section along the thickness direction of the surface protective layer. Also, the microscope image in Figure 3 is a planar image obtained with a laser microscope (Olympus OLS-4000).

[0026] The decorative material 11 shown in Figure 1 includes a base material B and a decorative sheet 1 attached thereto. Here, the decorative material 11 is a decorative board. The decorative board may be flat, bent, or folded. The decorative material 11 may have a shape other than a board.

[0027] In this case, base material B is a board. The board material is, for example, a wood-based board, an inorganic board, a metal plate, or a composite board made of multiple materials. Base material B may have a shape other than a board.

[0028] The decorative sheet 1 includes a base layer 2, a pattern layer 3, a transparent resin layer 4, a surface protection layer 5, an adhesive layer 7, a primer layer 6, and a concealing layer 8. The pattern layer 3, adhesive layer 7, transparent resin layer 4, and surface protection layer 5 are provided in this order from the base layer 2 side on the side of the base layer 2 opposite to the side facing the substrate B. The concealing layer 8 and primer layer 6 are provided in this order from the base layer 2 side on the side of the base layer 2 facing the substrate B. One or more of the pattern layer 3, transparent resin layer 4, primer layer 6, adhesive layer 7, and concealing layer 8 may be omitted. The elements included in the decorative sheet 1 will be described in order below.

[0029] <1.1>Primitive layer For the base layer 2 or its materials, any material can be arbitrarily 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 fabrics include organic and inorganic nonwoven fabrics. Examples of metals for metal foil include aluminum, iron, gold, and silver.

[0030] The thickness of the base material layer 2 is preferably within the range of 20 μm to 250 μm, taking into consideration factors such as printability and cost.

[0031] <1.2>Primary layer When an olefin-based resin is used as the material for the base layer 2, the surface of the base layer 2 is often inert. Therefore, in this case, it is preferable to provide a primer layer 6 between the base layer 2 and the substrate B. When the base layer 2 is made of an olefin-based material, the primer layer 6 may be omitted, and in order to improve the adhesion between the base layer 2 and the substrate B, the base layer 2 may be subjected to surface modification treatments such as corona treatment, plasma treatment, ozone treatment, electron beam treatment, ultraviolet treatment, or dichromate treatment.

[0032] As for the material of the primer layer 6, for example, the materials described later for the pattern layer 3 can be used. Since the primer layer 6 is applied to the back surface of the decorative sheet 1, and considering that the decorative sheet 1 is wound in a web-like shape, an inorganic filler may be added to the primer layer 6 to avoid blocking and to improve adhesion with the adhesive. Examples of inorganic fillers include silica, alumina, magnesia, titanium oxide, and barium sulfate.

[0033] <1.3> Concealing layer To impart opacity to the decorative sheet 1 relative to the base material B, for example, a colored sheet can be used as the base layer 2, or an opaque opacity layer 8 can be provided. The opacity layer 8 can be made of the same material as that used for the pattern layer 3, as described later. However, since the purpose of the opacity layer 8 is opacity, it is preferable to use opaque pigments, such as titanium dioxide or iron oxide, as the pigment. Furthermore, to enhance opacity, metals such as gold, silver, copper, or aluminum can be added to the material of the opacity layer 8. Generally, flake-shaped aluminum pieces are often added.

[0034] <1.4>Pattern Layer The pattern layer 3 is a layer formed by printing a pattern onto the base material layer 2 using ink. As the ink binder, for example, nitrated cotton, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, polyurethane, acrylic, polyesters, or modified versions thereof can be used individually or in combination. The binder may be water-based, solvent-based, or emulsion type, and may be a one-component type or a two-component type using a curing agent. The pattern layer 3 may also be formed by curing a layer formed with a curable ink by irradiation with ultraviolet light or electron beams. Among these, the most common method is to use a urethane-based ink and cure it with isocyanate. In addition to the binder, the ink used to form the pattern layer 3 may further contain, for example, pigments, dyes, and other colorants, extender pigments, solvents, and various additives found in ordinary inks. Examples of highly versatile pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolon, cobalt, phthalocyanine, carbon, titanium dioxide, iron oxide, mica, and other pearl pigments.

[0035] In addition to ink application, it is also possible to apply designs to the pattern layer 3 by vapor deposition or sputtering of various metals. In particular, it is preferable that a light stabilizer is added to the ink. This suppresses the deterioration of the decorative sheet 1 itself caused by light degradation of the ink, and extends the lifespan of the decorative sheet 1.

[0036] <1.5>Adhesive layer The adhesive layer 7 is also called the heat-sensitive adhesive layer, anchor coat layer, or dry lamination adhesive layer.

[0037] The resin material of the adhesive layer 7 is not particularly limited, but can be appropriately selected from resin materials such as acrylic, polyester, polyurethane, and epoxy. 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 after forming the adhesive layer 7 on the upper surface of the pattern layer 3 by gravure coating, the transparent resin layer 4 is laminated. Note that the adhesive layer 7 can be omitted if sufficient adhesive strength is obtained between the transparent resin layer 4 and the pattern layer 3.

[0038] <1.6>Transparent resin layer As the resin material for the transparent resin layer 4, olefin-based resins are preferably used. Examples of olefin-based resins include polypropylene, polyethylene, polybutene, and 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 include homopolymers of (such as -ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, etc.) 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.

[0039] 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. Various additives such as heat stabilizers, light stabilizers, blocking inhibitors, catalyst scavengers, colorants, light scattering agents, and gloss adjusters may be added to the transparent resin layer 4 as needed. Generally, phenol-based, sulfur-based, phosphorus-based, and hydrazine-based heat stabilizers are used, and hindered amine-based light stabilizers are used, in any combination.

[0040] <1.7>Surface protective layer The surface protective layer 5 includes a core portion 5A and a plurality of ridge-like portions 5B, each of which protrudes in a ridge-like manner from one surface of the core portion 5A. These ridge-like portions 5B form an uneven surface structure.

[0041] Here, in the decorative sheet 1 according to this embodiment, "ridged" refers to a convex shape that is linear in plan view. The ridged portion 5B may be curved or straight in plan view, but it is preferable that it be curved from the viewpoint of fingerprint resistance of the decorative sheet 1. Each of the ridged portions 5B may or may not be branched in plan view. In this disclosure, the ridged portion 5B is, for example, the portion from the lowest part to the tip of the uneven structure provided on the surface of the surface protective layer 5, and the core portion 5A refers to the portion of the surface protective layer 5 excluding the ridged portion 5B.

[0042] As shown in Figure 3, for example, each of the ridge-like portions 5B is curved, and at least a portion of them are adjacent in the width direction. At the positions where at least a portion of the ridge-like portions 5B are adjacent in the width direction, the cross-section of the surface protective layer 5 parallel to this width direction and the thickness direction of the surface protective layer 5, as shown in Figure 2, has a wave shape such as a sinusoidal shape in the portion where the uneven structure is provided.

[0043] The surface protection layer 5 has a power spectrum image obtained by performing a two-dimensional fast Fourier transform on the surface shape image of its uneven structure. When the average brightness in the spatial frequency range of 95 cycles / mm to 105 cycles / mm is defined as P_100, the average brightness in the spatial frequency range of 195 cycles / mm to 205 cycles / mm is defined as P_200, and the average brightness in the spatial frequency range of 695 cycles / mm to 705 cycles / mm is defined as P_700, and the ratio of the difference between P_100 and P_700 to the difference between P_200 and P_700 is defined as Rt_P, the average value of Rt_P is within the range of 1.57 to 1.82.

[0044] Here, the average value of Rt_P is obtained by the following method. First, a surface shape image of the uneven structure on the surface of the surface protective layer 5 is acquired using a laser microscope. This surface shape image has brightness corresponding to its height.

[0045] For the laser microscope, an Olympus OLS-4000 can be used. For surface topography imaging, an image with 10x magnification of the objective lens and 1024 pixels in both the horizontal and vertical directions is acquired.

[0046] Next, regions with 756 pixels in both the horizontal and vertical directions are extracted from this surface shape image and used as the FFT image. This FFT image is then subjected to a two-dimensional Fast Fourier Transform to obtain a power spectrum image in which the intensity (power) of the spatial frequency components is expressed as brightness.

[0047] This power spectrum image may be transformed so that the radial direction corresponds to the spatial frequency. That is, the first and third quadrants may be swapped, and the second and fourth quadrants may be swapped, and the spatial frequency at the center may be set to zero.

[0048] For image processing software such as the two-dimensional Fast Fourier Transform, ImageJ (version 1.53f or later) can be used. Furthermore, before performing the two-dimensional Fast Fourier Transform, the original image is centered and zero-padding is applied to set the number of pixels in each direction (vertical and horizontal) to 1024. The output power spectrum image will be a 32-bit image with 1024 pixels in each direction (vertical and horizontal).

[0049] Next, Rt_P is obtained from the above power spectrum image using the following method. First, P_100, P_200, and P_700 are calculated from the above power spectrum image. P_100 is the average value obtained by extracting pixels with a spatial frequency in the range of 95 cycles / mm to 105 cycles / mm from the above power spectrum image and dividing the sum of the brightness of these pixels by the number of these pixels. P_200 is the average value obtained by extracting pixels with a spatial frequency in the range of 195 cycles / mm to 205 cycles / mm from the above power spectrum image and dividing the sum of the brightness of these pixels by the number of these pixels. P_700 is the average value obtained by extracting pixels with a spatial frequency in the range of 695 cycles / mm to 705 cycles / mm from the above power spectrum image and dividing the sum of the brightness of these pixels by the number of these pixels. Then, calculate the ratio of the difference between P_100 and P_700 to the difference between P_200 and P_700, and define this as Rt_P.

[0050] The surface topography images described above are acquired using a laser microscope at 10 locations on the same surface protective layer, and Rt_P is obtained from each of these surface topography images using the method described above. The locations for acquiring the surface topography images are selected randomly. Then, the average value of Rt_P is obtained by calculating and averaging these Rt_P values.

[0051] The average value of Rt_P is one of the characteristics of the surface protective layer 5 that affects the tactile feel of the decorative sheet 1.

[0052] When the average value of Rt_P is within the above range, when a user presses their skin against the surface of the protective layer 5 and slides their skin across it, for example, when a user presses their finger against the surface of the protective layer 5 and slides their finger across it, the user is given a "moist touch." That is, because the slopes of the uneven shape on the surface of the protective layer 5 of this decorative sheet 1 are relatively gentle, when touched by the above action, the contact area between the finger and the raised surface can be gradually increased while keeping the pressure resistance due to contact between the finger and the surface low. As a result, a touch sensation is obtained in which the surface of the decorative sheet adheres to the finger.

[0053] On the other hand, in decorative sheets where the average value of Rt_P exceeds the upper limit, the slopes of the uneven surface on the surface protective layer 5 are even gentler than those of decorative sheet 1, which gives a "moist feel." Therefore, when pressing down on the surface with a finger and sliding the finger across it, the resistance to pressing due to the contact between the finger and the surface is smaller, and the contact area between the finger and the raised surface increases rapidly with pressure. Consequently, the contact area between the finger and the raised surface becomes large from the start of the pressing motion, and the user does not feel the presence of the unevenness. In this case, a feeling of the decorative sheet surface sticking to the finger is obtained, while a smoother feel is obtained compared to the "moist feel" described above, and the overall impression of a smooth feel is stronger. This feel can be associated with a "smooth feel."

[0054] Furthermore, decorative sheets with an average Rt_P value below the lower limit have steeper slopes in the uneven surface of the surface protective layer 5 compared to decorative sheet 1, which gives a "moist feel." Therefore, when pressing down on the surface with a finger and sliding the finger across it, the resistance to pressing due to the contact between the finger and the surface is greater, and the contact area between the finger and the raised surface increases gradually with pressure. Consequently, such decorative sheets do not have as large a contact area between the finger and the raised surface during pressing as decorative sheets that give a "moist feel" or a "smooth feel." As a result, such decorative sheets give a tactile sensation that makes the presence of unevenness on the surface feel present, and compared to the case of the "moist feel" described above, they give a rougher, more tactile sensation, resulting in a stronger overall impression of unevenness. This sensation can be associated with a "rough feel."

[0055] The thickness t of the surface protective layer 5 is 2 μm or more and 18 μm or less. Preferably, the thickness t of the surface protective layer 5 is 3 μm or more and 10 μm or less.

[0056] Here, the thickness of the surface protection layer 5 is the thickness of a layer that has the same apparent area and volume as the surface protection layer 5 and has a flat surface. The thickness of the surface protection layer 5 can be determined, for example, by the following method. First, a cross-section is imaged that is parallel to the thickness direction of the surface protection layer 5 and perpendicular to the length direction of the ridged portion 5B. Next, from this cross-sectional image, the dimensions of the surface protection layer 5 in the width direction of the ridged portion 5B and the area of ​​the cross-section of the surface protection layer 5 are determined. The thickness of the surface protection layer 5 is the value obtained by dividing this area by the above dimensions. Note that if the coating liquid for the surface protection layer, which will be described later, does not contain a solvent, the thickness of the coating film made from the coating liquid for the surface protection layer is equal to the thickness of the surface protection layer 5.

[0057] Increasing the thickness of the surface protective layer 5 tends to increase the average value of Rt_P. Therefore, if the thickness of the surface protective layer 5 is too small or too large, it becomes difficult to achieve a "moist touch." Also, if the thickness of the surface protective layer 5 is too small, it becomes difficult to achieve a low gloss level.

[0058] While a "moist texture" can be achieved if Rt_P is within the specified range, there are exceptions. These exceptions occur when the thickness of the surface protective layer 5 is either too small or too large.

[0059] If the surface protective layer 5 is too thin, when you press down on the surface with your finger and slide your finger across it, the resistance to pressing due to the contact between your finger and the surface will be smaller, and the contact area between your finger and the surface of the protrusions will increase rapidly with pressure. Therefore, since the contact area between your finger and the surface of the protrusions is large from the start of the pressing motion, you will not feel the presence of the bumps. In this case, you will get a tactile sensation where the surface of the decorative sheet feels like it is sticking to your finger, while at the same time getting a smoother tactile sensation compared to the "moist tactile sensation" described above, and the overall impression of a smooth tactile sensation will be stronger. This tactile sensation can be described as a "smooth tactile sensation."

[0060] If the surface protective layer 5 is too thick, when pressing down on the surface with a finger and sliding the finger across it, the resistance to pressing due to the contact between the finger and the surface will be large, and the contact area between the finger and the surface of the protrusions will increase gradually with increasing pressure. Therefore, such a decorative sheet will not have as large a contact area between the finger and the surface of the protrusions during pressing as a decorative sheet that provides a "moist" or "smooth" feel. As a result, such a decorative sheet will give a tactile sensation that makes one feel the presence of irregularities on its surface, and will also give a rougher feel compared to the "moist" feel described above, resulting in a stronger overall impression of a textured surface. This texture can be described as a "rough" feel.

[0061] The surface protective layer 5 contains cured resin and particles. The resin contained in the surface protective layer 5 is preferably an ionizing radiation-curable resin. Here, "ionizing radiation" refers to charged particle beams such as electron beams. Ionizing radiation-curable resins harden when irradiated with ionizing radiation. Ionizing radiation-curable resins can also be hardened by ultraviolet irradiation. The ionizing radiation-curable resin used here hardens when irradiated with light with a wavelength of 200 nm or less, while having a large absorption coefficient for this light.

[0062] The amount of cured ionizing radiation-curable resin in the surface protective layer 5 is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more. As the ionizing radiation-curable resin, known materials such as various monomers and commercially available oligomers can be used, for example, (meth)acrylic resins, silicone resins, polyester resins, urethane resins, amide resins, and epoxy resins can be used. The ionizing radiation-curable resin may be either an aqueous resin or a non-aqueous (organic solvent) resin.

[0063] The main component of the ionizing radiation-curable resin is preferably acrylate. Here, the main component of the ionizing radiation-curable resin means a component that accounts for 60% by mass or more of the ionizing radiation-curable resin. The ionizing radiation-curable resin preferably contains acrylate in an amount of 70 parts by mass or more, and more preferably 80 parts by mass or more. The ionizing radiation-curable resin is more preferably acrylate.

[0064] The acrylate is preferably a two-functional or more-functional acrylate, and more preferably a three-functional or more-functional acrylate. For obtaining a surface protective layer 5 with excellent scratch resistance, it is preferable that the acrylate be three-functional or more. There is no upper limit to the number of functional groups in the acrylate, but one example suggests it is six-functional or less.

[0065] The acrylate preferably contains a repeating structure. This repeating structure is, for example, one of the following: an ethylene oxide (EO) structure, a propylene oxide (PO) structure, or an ε-caprolactone (CL) structure. The repeating structure is preferably ethylene oxide or propylene oxide. In the acrylate, the above repeating structure may be interposed between the acryloyl group and the methylol group in an open ring state.

[0066] The number of repetitions of the repeating structure is preferably 3 or more. When an acrylate with a high number of repetitions is used, expansion in the in-plane direction of the cured film is more likely to occur in the first irradiation step described later, and therefore, wrinkles corresponding to the ridged parts 5B are more likely to occur on the surface of the coating film. In addition, when an acrylate with a high number of repetitions is used, the value of the relative Rt_P tends to increase. However, increasing the number of repetitions reduces the crosslinking density and decreases the scratch resistance of the surface protective layer.

[0067] In a preferred embodiment, the ionizing radiation-curable resin is a trifunctional acrylate containing a repeating structure. Examples of trifunctional acrylates containing a repeating structure are EO-modified, PO-modified, or CL-modified trimethylolpropane triacrylate, glycerin triacrylate, isocyanurate triacrylate, or pentaerythritol triacrylate. In the trifunctional acrylate containing a repeating structure, the number of repetitions of the repeating structure is preferably 3 or more, more preferably 3 to 30, and even more preferably 3 to 20.

[0068] In another preferred embodiment, the ionizing radiation-curable resin is a tetrafunctional acrylate containing a repeating structure. The tetrafunctional acrylate containing a repeating structure is, for example, EO-modified, PO-modified, or CL-modified pentaerythritol tetraacrylate. In the tetrafunctional acrylate containing a repeating structure, the number of repetitions of the repeating structure is preferably 12 or more, more preferably 12 to 50, even more preferably 20 to 50, and still more preferably 20 to 35.

[0069] The number of repetitions in the above repeating structure can be analyzed using MALDI-TOF-MS. Ionizing radiation-curable resins may have a molecular weight distribution. If a molecular weight distribution exists, the number of repetitions should be the number of repetitions corresponding to the molecular weight with the strongest peak in the MALDI-TOF-MS mass spectrum.

[0070] The particles included in the surface protective layer 5 may be, for example, particles made of organic materials such as polyethylene (PE) wax, polypropylene (PP) wax, or resin beads, or particles made of inorganic materials such as silica, glass, alumina, titania, zirconia, calcium carbonate, or barium sulfate.

[0071] The particles have an average particle size (D50) of 3 μm or more. Preferably, the average particle size (D50) of the particles is 3 μm or more and 11 μm or less, and more preferably 4 μm or more and 10 μm or less.

[0072] If the surface protective layer 5 contains particles, wrinkles can be generated more uniformly on the coating surface in the first irradiation step described later. If the average particle size (D50) is increased, the particles are more likely to fall off the surface protective layer 5, which may make it difficult to achieve high scratch resistance. If the particles are small, the effect of generating wrinkles uniformly is small, and it affects the uneven shape, making it difficult to obtain a moist feel.

[0073] Here, "average particle size" or "average particle size (D50)" refers to the median diameter (D50) measured by a laser diffraction / scattering particle size distribution analyzer. Note that if the coating liquid for the surface protection layer contains particles, the surface protection layer 5 obtained from this coating liquid will also contain particles. The average particle size of the particles contained in the surface protection layer 5 can be determined by observing its cross-section, measuring the particle sizes of multiple particles, and averaging the result. The value obtained in this way is substantially the same as the median diameter (D50) measured by a laser diffraction / scattering particle size distribution analyzer. Therefore, the range of average particle size described above can also be interpreted as the range of average particle size of the particles contained in the surface protection layer 5.

[0074] The particles are included in the surface protective layer 5 in an amount of 3 parts by mass to 11 parts by mass per 100 parts by mass of resin. Preferably, the amount of particles added is 4 parts by mass to 10 parts by mass per 100 parts by mass of resin. Note that "100 parts by mass of resin" refers to the parts by mass of the solid content of the resin.

[0075] When the amount of added particles is within the above range, the effect of creating wrinkles uniformly is particularly great. If the amount of added particles is too high, the particles are more likely to fall off the surface protective layer 5, making it difficult to achieve high scratch resistance. If the amount of added particles is too low, it will affect the uneven surface shape, making it difficult to obtain a moist feel.

[0076] The gloss of the surface protective layer 5 is less than 10. Preferably, the gloss of the surface protective layer 5 is 5 or less. Here, "gloss" is the measured value when measured at an incident angle of 60 degrees using a gloss meter compliant with JIS Z8741:1997.

[0077] <2> Manufacturing method of decorative sheets The decorative sheet 1 is manufactured, for example, by the following method. For simplicity, the descriptions of the pattern layer 3, transparent resin layer 4, primer layer 6, adhesive layer 7, and concealing layer 8 are omitted here.

[0078] First, a coating film consisting of a surface protective coating liquid is formed on one side of the raw material 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 by various coating methods such as roll coating, knife coating, microgravure coating, and die coating.

[0079] The coating solution for the surface protective layer contains the resin and the particles described above. The coating solution for the surface protective layer may further contain a solvent and additives for improving the functionality of the final product, such as antimicrobial agents and antifungal agents. The coating solution for the surface protective layer may further contain other additives such as ultraviolet absorbers and light stabilizers. Examples of ultraviolet absorbers that can be used include benzotriazole-based, benzoate-based, benzophenone-based, and triazine-based types. Examples of light stabilizers that can be used include hindered amine-based types. Furthermore, according to the method described herein, a surface protective layer 5 having low gloss can be formed without gloss modifiers (matte additives).

[0080] In the second irradiation step described later, when the entire coating film consisting of the surface protective layer coating liquid is cured by ultraviolet irradiation, it is preferable that the surface protective layer coating liquid further contains a photoinitiator. The photoinitiator is not particularly limited, but examples include benzophenone-based, acetophenone-based, benzoin ether-based, and thioxanthone-based photoinitiators.

[0081] After forming a coating film consisting of a surface protection coating liquid, a first irradiation step is performed. In the first irradiation step, light with a wavelength of 200 nm or less (hereinafter referred to as first radiation) is irradiated onto the coating film. The ionizing radiation-curable resin contained in the surface protection coating liquid has a large absorption coefficient for first radiation. Therefore, first radiation incident on the coating film can only reach a distance of tens to hundreds of nanometers from its outermost surface. Consequently, in the first irradiation step, a crosslinking reaction proceeds in the surface region of the coating film, forming an extremely thin cured film, while other regions remain uncured as the crosslinking reaction does not proceed.

[0082] The coating film after the first irradiation process has wrinkles on its surface corresponding to the ridged portion 5B. The inventors believe the reason why wrinkles form on the coating film surface due to the first irradiation process is as follows.

[0083] As described above, the first radiation can only reach a distance of tens to hundreds of nanometers from the outermost surface of the coating film. In other words, the crosslinking reaction of the ionizing radiation-curable resin occurs only at the surface of the coating film, and regions further than tens to hundreds of nanometers from the outermost surface remain uncured, containing highly fluid molecules. These highly fluid molecules increase the volume of the cured film by causing it to swell. The in-plane compressive stress caused by this increase in volume in the in-plane direction leads to buckling of the cured film, resulting in wrinkles on the coating film surface.

[0084] The first type of radiation can be extracted from excimer VUV (Vacuum Ultra Violet) light. Excimer VUV light can be generated from lamps using noble gases or noble gas halide compounds. When high-energy electrons are supplied from an external source to a lamp containing a noble gas or noble gas halide compound, numerous discharge plasmas (dielectric barrier discharges) are generated. This plasma discharge excites the atoms of the discharge gas (noble gas), causing them to instantaneously enter an excimer state. When returning from this excimer state to the ground state, light in the wavelength range specific to the excimer state is emitted.

[0085] The gas used in an excimer lamp can be any conventionally used gas, as long as it emits light of 200 nm or less. As gases, noble gases such as Xe, Ar, and Kr, or mixed gases of noble gases and halogen gases such as ArBr and ArF can be used. The wavelength (center wavelength) of an excimer lamp varies depending on the gas used, and 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).

[0086] Considering the magnitude of the photon energy and the difference between the wavelength and the bonding energy of the organic material, it is preferable to use a xenon lamp that emits excimer light with a central wavelength of 172 nm as the light source. Furthermore, considering the costs of equipment maintenance and material availability, it is also preferable to use a xenon lamp as the light source.

[0087] The first irradiation step is carried out in an atmosphere with a low oxygen concentration. Oxygen has a large absorption coefficient for light below 200 nm. Therefore, it is preferable to carry out the first irradiation step in a nitrogen gas atmosphere, for example. The oxygen concentration in the gas phase during the first irradiation step, i.e., the residual oxygen concentration in the reaction atmosphere, is preferably 2000 ppm or less, and more preferably 1000 ppm or less.

[0088] In addition, oxygen in the atmosphere inhibits radical polymerization. Therefore, the residual oxygen concentration in the reaction atmosphere affects the formation of wrinkles on the coating film surface. Therefore, changing the residual oxygen concentration in the reaction atmosphere can also change the surface properties of the surface protective layer 5.

[0089] The integrated light quantity of the first radiation is 0.5 mJ / cm 2 or more and 200 mJ / cm 2 or less, preferably 1 mJ / cm 2 or more and 100 mJ / cm 2 or less, more preferably 3 mJ / cm 2 or more and 50 mJ / cm 2 or less, still more preferably 5 mJ / cm 2 or more and 30 mJ / cm 2 or less, and most preferably. When the integrated light quantity is reduced, the expansion of the cured film in the in-plane direction becomes smaller. When the integrated light quantity is increased, the surface state of the coating film deteriorates.

[0090] After the first irradiation step is completed, the second irradiation step is carried out. In the second irradiation step, the coating film is irradiated with the second radiation to cure the entire coating film. Thereby, the surface protective layer 5 is obtained.

[0091] The second radiation is ionizing radiation such as an electron beam or ultraviolet light having a longer wavelength than the first radiation. When ultraviolet light is used as the second radiation, this ultraviolet light shall have a wavelength at which the radiation-curable resin exhibits a smaller absorption coefficient.

[0092] The integrated light quantity of the second radiation is 10 mJ / cm 2 or more and 500 mJ / cm 2 or less, preferably 50 mJ / cm 2 or more and 400 mJ / cm 2 or less, more preferably 100 mJ / cm 2 or more and 300 mJ / cm 2 or less, and still more preferably.

[0093] <3> Effect The decorative sheet 1 described with reference to Figures 1 to 3 has a surface protective layer 5 having the surface properties and thickness described above. When a user presses their skin against the surface of the surface protective layer 5 and slides their skin across the surface, for example, when a user presses their finger against the surface of the surface protective layer 5 and slides their finger across the surface, the decorative sheet 1 provides the user with a moist tactile sensation. That is, because the slopes of the uneven shape on the surface of the surface protective layer 5 of this decorative sheet 1 are relatively gentle, when touched by the above action, the contact area between the finger and the raised surface can be gradually increased while keeping the pressure resistance due to contact between the finger and the surface low. As a result, a tactile sensation is obtained in which the surface of the decorative sheet adheres to the finger.

[0094] The moist texture of the decorative sheet 1 can give a person who touches it a feeling of comfort and warmth. Furthermore, the moist texture can give the decorative sheet 1 a sense of luxury. Therefore, the decorative sheet 1, which provides a moist texture to the user, is suitable for applications where the user's skin comes into frequent contact with the sheet or where the user's skin is in contact with the sheet for extended periods, such as desk tops, chair armrests, and handrails on stairs and in passageways.

[0095] The surface protection layer 5 of the decorative sheet 1 has the surface properties described above, so it can achieve a low gloss level even without containing a gloss adjuster (matte additive). Gloss adjusters reduce the oil repellency of the layer formed by the resin material, so a surface protection layer 5 containing a gloss adjuster is prone to fingerprints. A surface protection layer 5 without a gloss adjuster does not easily absorb oil, so fingerprints are less likely to adhere to it. In addition, a surface protection layer 5 with excellent oil repellency is less likely to cause oil stains or the adsorption of contaminants. Furthermore, when the surface of a surface protection layer 5 without a gloss adjuster is scratched, the particles of the gloss adjuster do not fall off, and therefore, a decorative sheet 1 containing such a surface protection layer 5 is less likely to experience changes in gloss or scratches.

[0096] The surface protective layer 5 having the above surface properties can be obtained by the method described above for the following reasons.

[0097] Oxygen in the gas phase not only absorbs short-wavelength ultraviolet light but also inhibits radical polymerization. The effect of oxygen in the gas phase on radical polymerization is greatest in the portion of the coating film made of 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 first irradiation step, the relationship between the distance from the coating film surface and the progress of the crosslinking reaction can be changed.

[0098] When this relationship changes, the thickness of the cured film formed on the surface of the coating by the first irradiation process and the degree of in-plane expansion of the cured film in accordance with the progress of the crosslinking reaction change. The cumulative amount of light in the first irradiation process also affects the thickness of the cured film and the degree of in-plane expansion of the cured film. Furthermore, the thickness of the cured film and the degree of in-plane expansion of the cured film affect the surface properties of the surface protective layer. In addition, the particle size and amount of particles added in the coating film, as well as the thickness of the coating film, also affect wrinkle formation.

[0099] Therefore, by appropriately setting, for example, the composition of the ionizing radiation-curable resin, the particle size and amount added, the thickness of the coating film, the oxygen concentration in the gas phase during the first irradiation step, and the integrated light amount during the first irradiation step, a surface protective layer having the desired surface properties can be obtained. [Examples]

[0100] Examples of the present invention are described below. Note that the "particle size" described below refers to the "average particle size (D50)" mentioned above.

[0101] <Example 1> The decorative sheet 1, as described with reference to Figures 1 to 3, was manufactured by the following method. In this example, the transparent resin layer 4, primer layer 6, adhesive layer 7, and concealing layer 8 were omitted.

[0102] First, the basis weight is 50 g / m². 2Impregnated paper (GFR-506: manufactured by Kojin Co., Ltd.) was prepared as the base layer 2. On one side of the base layer 2, the pattern layer 3 was formed using oil-based nitrated cotton resin gravure printing ink (PCNT (PCRNT) various colors: manufactured by Toyo Ink Co., Ltd.).

[0103] Next, a protective coating solution for the surface layer was applied to the pattern layer 3. The protective coating solution used was a mixture of the following ionizing radiation-curable resin and the following particles. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 15 molar added) Product Name: SR9035 (manufactured by Sartomer) Blend: 100 parts by mass ·particle Product Name: Silysia 250N (Manufactured by Fuji Silysia Chemical Co., Ltd.) Particle size: 5μm Blend: 5 parts by mass The coating film, consisting of a surface protective coating liquid, was formed to a thickness of 5 μm.

[0104] Subsequently, the first irradiation process was carried out. Specifically, under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm, a Xe excimer lamp was used to emit ultraviolet light with a wavelength of 172 nm, accumulating to a total light intensity of 50 mJ / cm². 2 The irradiation was applied in such a manner that wrinkles were created on the surface of the coating.

[0105] Next, the second irradiation process was carried out. Specifically, the coating film was irradiated with ionizing radiation to harden the entire film, thereby forming a surface protective layer 5. In this way, decorative sheet 1 was obtained.

[0106] <Comparative Example 1> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point: in this example, no particles were incorporated. The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0107] <Comparative Example 2> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, the amount of particles was 2 parts by mass. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm, in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, under atmospheric pressure, onto the surface of the coating film consisting of a surface protective layer coating liquid, accumulating to a total light intensity of 90 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0108] <Example 2> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, the amount of particles was 3 parts by mass. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm, in a nitrogen gas atmosphere with an oxygen concentration of 250 ppm under atmospheric pressure, onto the surface of the coating film consisting of a surface protective layer coating liquid, with an integrated light intensity of 70 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0109] <Example 3> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, the amount of particles was 10 parts by mass. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 40 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 750 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0110] <Example 4> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, the amount of particles was 11 parts by mass. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 40 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 750 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0111] <Comparative Example 3> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, the amount of particles was 12 parts by mass. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 40 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 750 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0112] <Comparative Example 4> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, a coating film consisting of a surface protective layer coating liquid was formed to a thickness of 1 μm. The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0113] <Example 5> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, a coating film consisting of a surface protective layer coating liquid was formed to a thickness of 2 μm. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 80 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0114] <Example 6> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, a coating film consisting of a surface protective layer coating liquid was formed to a thickness of 3 μm. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm, in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm, under atmospheric pressure, onto the surface of the coating film consisting of a surface protective layer coating liquid, accumulating to a total light intensity of 70 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0115] <Example 7> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, a coating film consisting of a surface protective layer coating liquid was formed to a thickness of 10 μm. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 20 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 700 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0116] <Example 8> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, a coating film consisting of a surface protective layer coating liquid was formed to a thickness of 18 μm. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 10 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 700 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0117] <Comparative Example 5> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following point. Specifically, in this example, a coating film consisting of a surface protective layer coating liquid was formed to a thickness of 20 μm. The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 5 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 700 ppm. 2The irradiation was applied in such a manner that it resulted in the following:

[0118] <Comparative Example 6> Decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following points. That is, in this example, the following particles were used. ·particle Product Name: Silycia 310P (Manufactured by Fuji Silycia Co., Ltd.) Particle size: 2μm The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 40 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 600 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0119] <Example 9> Decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following points. That is, in this example, the following particles were used. ·particle Product Name: Silycia 420 (Manufactured by Fuji Silycia Co., Ltd.) Particle size: 3μm The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm, in a nitrogen gas atmosphere with an oxygen concentration of 550 ppm under atmospheric pressure, onto the surface of the coating film consisting of a surface protective layer coating liquid, accumulating to a total light intensity of 45 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0120] <Example 10> Decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following points. That is, in this example, the following particles were used. ·particle Product Name: Silysia 780 (manufactured by Fuji Silysia Chemical Co., Ltd.) Particle size: 11μm The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0121] <Comparative Example 7> Decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following points. That is, in this example, the following particles were used. ·particle Product Name: sicastar43-00-154 (Manufactured by Corefront Co., Ltd.) Particle size: 14μm The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0122] <Comparative Example 8> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Trimethylolpropane triacrylate Product Name: NK Ester A-TMPT (manufactured by Shin-Nakamura Chemical Co., Ltd.) The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0123] <Example 11> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 3 molar addition) Product Name: Miramer M3130 (Manufactured by Miwon) The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0124] <Example 12> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 6 molar addition) Product Name: Miramer M3160 (Manufactured by Miwon) The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0125] <Example 13> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 9 molar addition) Product Name: SR502 (Manufactured by Sartmar) The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 80 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 200 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0126] <Example 14> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 20 molar added) Product Name: NK Ester AT-20E (Manufactured by Shin-Nakamura Chemical Co., Ltd.) The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm, in a nitrogen gas atmosphere with an oxygen concentration of 600 ppm under atmospheric pressure, onto the surface of the coating film consisting of a surface protective layer coating liquid, with an integrated light intensity of 45 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0127] <Example 15> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (EO20 molar added) The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm, in a nitrogen gas atmosphere with an oxygen concentration of 600 ppm under atmospheric pressure, onto the surface of the coating film consisting of a surface protective layer coating liquid, with an integrated light intensity of 45 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0128] <Example 16> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (EO 35 molar addition) Product Name: NK Ester ATM-35E (Manufactured by Shin-Nakamura Chemical Co., Ltd.) The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 40 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 650 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0129] <Comparative Example 9> The decorative sheet 1 was manufactured in the same manner as in Example 1, except for the following: In this example, the number of repetitions of the repeating structure was 6, and the amount of particles was 15 parts by mass. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 6 molar addition) Product name: SR499 (manufactured by Sartmar) Furthermore, the first irradiation process was omitted, and the coating film, consisting of the surface protective layer coating liquid, was cured by the second irradiation process alone.

[0130] <Example 17> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Ethylene glycol diacrylate (EO9 molar addition) Product Name: Light Acrylate 9EG-A (Manufactured by Kyoeisha Chemical Co., Ltd.) The first irradiation step involves using a Xe excimer lamp to emit ultraviolet light with a wavelength of 172 nm at an integrated intensity of 40 mJ / cm² under atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 550 ppm. 2 The irradiation was applied in such a manner that it resulted in the following:

[0131] <Comparative Example 10> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Ethoxylated dipentaerythritol hexaacrylate (EO12 molar addition) Product Name: NK Ester A-DPH-12E (manufactured by Shin-Nakamura Chemical Co., Ltd.) The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0132] <Comparative Example 11> Except for the following points, decorative sheet 1 was manufactured in the same manner as in Example 1. That is, in this example, the following ionizing radiation-curable resin was used. ·Ionizing radiation curable resin Type: Pentaerythritol tetraacrylate Product Name: NK Ester A-TMMT (manufactured by Shin-Nakamura Chemical Co., Ltd.) The first irradiation step involves using a Xe excimer lamp to irradiate the surface of a coating film made of a surface protective layer liquid with ultraviolet light of 172 nm at atmospheric pressure and in a nitrogen gas atmosphere with an oxygen concentration of 100 ppm, until the integrated light intensity reaches 100 mJ / cm². 2 The irradiation was applied in such a manner that it resulted in the following:

[0133] <Rating> The following evaluations were performed on each of the above-mentioned decorative sheets.

[0134] (1) Mean value of Rt_P For each of the decorative sheets mentioned above, the average value of Rt_P was calculated using the same method as described above.

[0135] (2) Thickness of the surface protective layer The thickness of the surface protection layer was measured using the same method as described above. Specifically, decorative sheet 1 was embedded in a resin such as a cold-curing epoxy resin or a UV-curing resin, and the resin was allowed to cure completely. Next, this was cut so that the cross-section of decorative sheet 1 was exposed, and the measurement surface was obtained by mechanical polishing. Subsequently, the cross-section of the surface protection layer was imaged using a scanning electron microscope SIGMA500 manufactured by Carl Zeiss Microscopy. For this imaging, the acceleration voltage was set to 0.5 keV (low acceleration voltage), the imaging mode was set to SE2 mode, and the magnification was set to 2000x. No sputtering was performed on the measurement sample. Next, from this cross-sectional image, the dimensions of the surface protection layer in the width direction of the ridged portion and the area of ​​the cross-section of the surface protection layer were determined. By dividing this area by the above dimensions, the "thickness t of the surface protection layer" was calculated. The "thickness t of the surface protection layer" obtained in this way was equal to the thickness of the coating film made of the coating liquid for the surface protection layer.

[0136] (3) Glossiness Glossiness was measured using a Rhopoint IQ (manufactured by Konica Minolta) at 60 degrees. The "60-degree gloss value" in Tables 1 to 4 below represents this 60-degree glossiness.

[0137] (4) Skin feel The skin texture was evaluated using the following method. First, preliminary preparations were made to ensure consistency in evaluation criteria among the evaluators. Specifically, three standard test specimens with different surface properties were prepared. Next, each of the five evaluators, blindfolded, was asked to press their fingers against the surface of the standard test specimens and slide their fingers across the surface, and then classify the tactile sensations into the following three groups. Group 1: There was almost no resistance when pressing down, and the presence of any bumps or irregularities was not felt. However, the surface of the decorative sheet had a tactile sensation that felt as if it was sticking to the fingers, and a smooth feel was obtained. Overall, the impression of a smooth feel was strong. In other words, a smooth feel was obtained. Group 2: There was almost no resistance when pressing, but the surface of the decorative sheet had a tactile sensation of sticking to the finger. However, it did not give the impression of being smooth to the touch. In other words, it had a moist tactile sensation. Group 3: Resistance to indentation was felt, along with the presence of irregularities. In other words, a rough texture was obtained.

[0138] The above procedure was repeated until the evaluations from each evaluator matched three or more times consecutively, and the evaluation results matched three or more times consecutively among the evaluators.

[0139] Next, for each of the above-mentioned cosmetic sheets, each of the evaluators was asked, blindfolded, to press their fingers against the surface of the protective layer and slide their fingers across the surface, and then classify the tactile sensation into the three groups described above. This procedure was repeated until the evaluations from each evaluator agreed three or more times in a row, and the evaluation results agreed three or more times in a row among the evaluators. Based on these results, the skin feel was evaluated according to the following criteria. A (Smooth): Group 1 B (Moist): Group 2 C (rough): Group 3

[0140] (5) Fingerprint resistance As part of the fingerprint resistance evaluation, we conducted an assessment of how easily fingerprints could be wiped off. Specifically, first, the 60-degree gloss of the surface of each decorative sheet was measured, and this 60-degree gloss was defined as the initial gloss. Next, a fingerprint-resistant evaluation solution was applied to the surface protective layer, and the solution adhering to the surface of the decorative sheet was wiped off. A higher fatty acid was used as the fingerprint-resistant evaluation solution. After that, the 60-degree gloss of the area from which the fingerprint-resistant evaluation solution had been wiped off was measured, and this 60-degree gloss was defined as the post-wipe gloss.

[0141] The fingerprint removal rate was calculated using the following formula. Fingerprint removal rate (%) = (Glossiness after wiping / Initial glossiness) × 100 The evaluation criteria were as follows: AA: 70% to less than 250% A: 50% or more but less than 70%, or 250% or more but less than 300% B: Less than 50%, or 300% or more.

[0142] (6) Stain resistance To evaluate stain resistance, a stain test A, as defined by the Japanese Agricultural Standards (JAS), was conducted. Specifically, lines 10 mm wide were drawn on the surface protective layer of each decorative sheet using blue ink, black quick-drying ink, and red crayon, and left for 4 hours. After that, the lines of blue ink, black quick-drying ink, and red crayon were wiped off with a cloth soaked in ethanol.

[0143] The evaluation criteria were as follows: AA: The lines of each color could be easily wiped away. A: I was able to wipe away some of the lines of each color, but some stains remained. B: I was unable to wipe away the lines of each color.

[0144] (7) Scratch resistance Each decorative sheet was attached to wood substrate B using a urethane-based adhesive. Subsequently, a steel wool rubbing test was conducted to evaluate scratch resistance. Specifically, the decorative sheet was rubbed back and forth 20 times with steel wool while applying a load of 100g, and scratches and changes in gloss on the surface of the decorative sheet were visually observed.

[0145] The evaluation criteria were as follows: AA: No scratches or changes in gloss occurred on the surface. A: Minor scratches and changes in gloss have occurred on the surface. B: Significant scratches or changes in gloss occurred on the surface.

[0146] (8) Processability The resulting decorative sheet was attached to the wood substrate B using a urethane-based adhesive, with the side facing the raw material layer (i.e., the back of the decorative sheet) facing the wood substrate B. Then, to prevent damage to the decorative sheet, a V-shaped groove was made up to the boundary where the wood substrate B and the decorative sheet were bonded together.

[0147] Next, the wood substrate B was bent to a 90-degree angle along the V-shaped groove so that the side of the decorative sheet facing the protective layer (i.e., the surface of the decorative sheet) was folded in a mountain fold. The bending properties were evaluated by observing the bent portion of the decorative sheet's surface using an optical microscope to check for whitening or cracking.

[0148] The evaluation criteria were as follows: AA: No whitening or cracking was observed. A: Some areas showed signs of albinism. B: Whitening was observed throughout the entire surface, or cracks were observed in some areas.

[0149] The evaluation results are shown in Tables 1 to 5.

[0150] [Table 1]

[0151] [Table 2]

[0152] [Table 3]

[0153] [Table 4]

[0154] [Table 5]

[0155] As shown in Tables 1 to 5, the decorative sheets according to Examples 1 to 17 gave the evaluators a smooth tactile feel. Furthermore, the decorative sheets according to Examples 1 to 17 had low gloss and excellent resistance to fingerprints, stains, scratches, and processability.

[0156] Comparative Example 3, as shown in Table 1, gave the evaluator a moist feel and had low gloss, but was inferior in terms of stain resistance, scratch resistance, and processability. Comparative Example 7, as shown in Table 3, gave the evaluator a moist feel, but was inferior in terms of scratch resistance.

[0157] In contrast, as shown in Tables 1 to 3 and 5, Comparative Examples 1, 2, 5, 6, and 9 did not give the evaluators a moist feel, but rather a rough feel. Also, as shown in Tables 2, 4, and 5, Comparative Examples 4, 8, 10, and 11 did not give the evaluators a moist feel, but rather a smooth feel. [Explanation of symbols]

[0158] 1... Decorative sheet, 2... Raw material layer, 3... Pattern layer, 4... Transparent resin layer, 5... Surface protection layer, 6... Primer layer, 7... Adhesive layer, 8... Concealing layer, 11... Decorative material, B... Substrate.

Claims

1. It comprises a raw material layer and a surface protection layer provided on one surface of the raw material layer, The surface of the aforementioned surface protective layer is provided with an uneven structure including a plurality of ridge-like portions, each of which protrudes in a ridge-like manner. Regarding the power spectrum image obtained by performing a two-dimensional fast Fourier transform on the surface shape image of the aforementioned uneven structure, if we define P_100 as the average brightness in the spatial frequency range of 95 cycles / mm to 105 cycles / mm, P_200 as the average brightness in the spatial frequency range of 195 cycles / mm to 205 cycles / mm, and P_700 as the average brightness in the spatial frequency range of 695 cycles / mm to 705 cycles / mm, and Rt_P as the ratio of the difference between P_100 and P_700 to the difference between P_200 and P_700, then the average value of Rt_P is within the range of 1.57 to 1.

82. The surface protective layer comprises a cured resin and particles, the particles having an average particle size of 3 μm or more, and being included in the surface protective layer in an amount of 3 parts by mass or more and 11 parts by mass or less per 100 parts by mass of the resin. The aforementioned surface protective layer has a thickness of 2 μm or more and 18 μm or less. A decorative sheet having a gloss level of less than 10 for the surface protective layer.

2. The decorative sheet according to claim 1, wherein the average particle size of the particles is 3 μm or more and 11 μm or less.

3. The decorative sheet according to claim 1 or 2, wherein the resin is an ionizing radiation-curable resin.

4. The decorative sheet according to any one of claims 1 to 3, wherein the resin is acrylate.

5. The decorative sheet according to any one of claims 1 to 4, wherein the resin is a trifunctional acrylate containing a repeating structure, and the number of repetitions of the repeating structure is 3 or more and 20 or less.

6. The decorative sheet according to any one of claims 1 to 4, wherein the resin is a tetrafunctional acrylate containing a repeating structure, and the number of repetitions of the repeating structure is 20 or more and 35 or less.

7. The decorative sheet according to any one of claims 1 to 6, further comprising a pattern layer between the base material layer and the surface protective layer.

8. A decorative sheet according to any one of claims 1 to 7, The base material to which the decorative sheet is attached and A decorative material that has the following features.

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