Decorative sheets and decorative materials

Abstract

We provide decorative sheets that reproduce the texture of genuine materials while offering superior durability. Furthermore, we offer high-quality decorative materials incorporating such decorative sheets. [Solution] A decorative sheet comprising a paper base layer, a pattern layer provided on one surface of the base layer, a partial pattern layer provided on the surface of the pattern layer and partially covering the pattern layer, and a surface protection layer provided on the surfaces of the pattern layer and the partial pattern layer and covering both surfaces, wherein the surface protection layer has a first protective layer with at least a portion of its surface exposed, the first protective layer does not contain a gloss adjuster, the surface of the first protective layer has an uneven structure, the uneven structure has a load length ratio Rmr(10%) at a cutting level of 10% of 0.4 or more and a root mean square slope Rdq of 0.15 or more and 0.4 or less.

Description

[Technical Field]

[0001] This invention relates to decorative sheets and decorative materials. [Background technology]

[0002] Traditionally, decorative sheets have been used to finish the surfaces of interior and exterior materials such as fixtures, furniture, joinery, and flooring in buildings such as houses, with the aim of adding aesthetic appeal and durability to these components. Decorative sheets are required to have durability such as scratch resistance and stain resistance so that the surface appearance is not impaired even after long-term use.

[0003] The aesthetic appeal of a decorative sheet is achieved by forming patterns, such as wood grain, on the sheet using various printing methods. Durability is generally achieved by forming a protective surface layer on the outermost surface of the decorative sheet. Surface gloss is also an important element of the aesthetic appeal of a decorative sheet, and in particular, to achieve low gloss, it is common to add a gloss adjuster (matte additive) to the protective surface layer.

[0004] One example of a decorative sheet that uses a gloss adjuster in the surface protective layer to adjust the surface gloss and add design features is the decorative sheet described in Patent Document 1. The decorative sheet described in Patent Document 1 comprises a first surface protective layer formed on a pattern layer and a second surface protective layer partially formed on the first surface protective layer. In this decorative sheet, the gloss is increased in the first surface protective layer without adding a gloss adjuster, and the gloss is decreased in the second surface protective layer by adding a gloss adjuster, such as silica particles, thereby adding a design feature of visual three-dimensionality. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2017-136766 Public Relations [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, while the technology described in Patent Document 1 can, for example, provide a decorative sheet that visually mimics the three-dimensional appearance of wood, there is room for improvement in reproducing the coldness and texture felt when touching real wood.

[0007] Furthermore, in the technology described in Patent Document 1, the low gloss of the second surface protective layer is achieved by adding a gloss modifier to the second surface protective layer. However, the addition of the gloss modifier reduces the oil repellency of the surface protective layer, making it prone to fingerprints and other marks. In addition, when the surface of the decorative sheet is rubbed, the gloss modifier peels off, making it prone to scratches, changes in gloss, and whitening phenomena such as clouding. For this reason, there has been a need for improved durability in decorative sheets that use gloss modifiers.

[0008] Based on the above circumstances, the present invention aims to provide a decorative sheet that reproduces the texture of genuine materials while being highly durable. Furthermore, it also aims to provide a high-quality decorative material incorporating such a decorative sheet. [Means for solving the problem]

[0009] To solve the above problems, one aspect of the present invention includes the following aspects.

[0010] [1] A decorative sheet comprising a paper base layer, a pattern layer provided on one surface of the base layer, a partial pattern layer provided on the surface of the pattern layer and partially covering the pattern layer, and a surface protection layer provided on the surfaces of the pattern layer and the partial pattern layer and covering both surfaces, wherein the surface protection layer has a first protective layer on which at least a portion of the surface is exposed, the first protective layer does not contain a gloss adjuster, the surface of the first protective layer has an uneven structure, the uneven structure has a load length ratio Rmr(10%) at a cutting level of 10% of 0.4 or more and a root mean square slope Rdq of 0.15 or more and 0.4 or less.

[0011] [2] The surface protective layer has a first protective layer covering the surfaces of the pattern layer and the partial pattern layer, and a second protective layer covering a part of the surface of the first protective layer and laminated on the first protective layer. The second protective layer has a higher glossiness than the first protective layer. The decorative sheet according to [1].

[0012] [3] The surface protective layer has a second protective layer covering the surfaces of the pattern layer and the partial pattern layer, and a first protective layer covering a part of the surface of the second protective layer and laminated on the second protective layer. The second protective layer has a higher glossiness than the first protective layer. The decorative sheet according to [1].

[0013] [4] In plan view, the region where the first protective layer is exposed and the partial pattern layer are in sync. The decorative sheet according to [2] or [3].

[0014] [5] In plan view, the region where the second protective layer is exposed and the partial pattern layer are in sync. The decorative sheet according to [2] or [3].

[0015] [6] The glossiness of the first protective layer is less than 10. The decorative sheet according to any one of [1] to [5].

[0016] [7] The first protective layer contains a cured product of a resin and particles. The decorative sheet according to any one of [1] to [6].

[0017] [8] The particles have an average particle diameter of 3 μm or more and 11 μm or less. The decorative sheet according to [7].

[0018] [9] The first protective layer contains 3 parts by mass or more and 11 parts by mass or less of the particles with respect to 100 parts by mass of the resin. The decorative sheet according to [7] or [8].

[0019]

[10] The resin is a radiation-curable resin. The decorative sheet according to any one of [7] to [9].

[0020]

[11] The decorative sheet according to any one of the items [7] to

[10] , wherein the precursor of the resin is acrylate.

[0021]

[12] The decorative sheet according to any one of the claims [7] to

[11] , wherein the resin precursor is a trifunctional acrylate having a repeating structure, and the number of repetitions of the repeating structure is 9 or more and 15 or less.

[0022]

[13] The decorative sheet according to any one of the claims [7] to

[12] , wherein the resin precursor is a tetrafunctional acrylate having a repeating structure, and the number of repetitions of the repeating structure is 20 or more and 25 or less.

[0023]

[14] The decorative sheet according to any one of the items [1] to

[13] , wherein the thickness of the surface protective layer is 9 m or more and 14 μm or less.

[0024] A decorative material comprising a decorative sheet according to any one of items [1] to

[14] and a substrate to which the decorative sheet is attached. [Effects of the Invention]

[0025] According to the present invention, it is possible to provide a decorative sheet that reproduces the texture of genuine materials while being highly durable. Furthermore, it is possible to provide high-quality decorative materials equipped with such a decorative sheet. [Brief explanation of the drawing]

[0026] [Figure 1] Figure 1 is a schematic diagram of the decorative sheet 1 and decorative material 100 according to the first embodiment. [Figure 2] Figure 2 is a micrograph of the surface of the surface protective layer 15. [Figure 3] Figure 3 is a schematic diagram showing the decorative sheet of the second embodiment. [Figure 4] Figure 4 is a schematic diagram showing the decorative sheet of the second embodiment. [Figure 5] Figure 5 is a schematic diagram showing the decorative sheet of the second embodiment. [Figure 6] Figure 6 is a schematic diagram showing the decorative sheet of the second embodiment. [Modes for carrying out the invention]

[0027] [First Embodiment] The decorative sheet according to this embodiment will be described below with reference to Figures 1 and 2. Note that in all the following drawings, the dimensions and proportions of each component have been varied as appropriate for clarity. The items described below can be incorporated into each of the above configurations, either individually or in combination.

[0028] 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.

[0029] Figure 1 is a schematic diagram of the decorative sheet 1 and decorative material 100 according to the first embodiment. As shown in Figure 1, the decorative sheet 1 has a base layer 12, a pattern layer 13, a partial pattern layer 14, and a surface protection layer 15. The decorative material 100 has the decorative sheet 1 and a base material 50. An adhesive layer or tack layer (not shown) is provided between the decorative sheet 1 and the base material 50.

[0030] The base material 50 is, for example, 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. The base material 50 may have a shape other than a board. The decorative material 100 having the base material 50 which is a board is a decorative panel. The decorative panel may be flat, bent, or folded.

[0031] The decorative material 100 may also employ a material other than a sheet as the base material 50. For example, the base material 50 may be a resin molded body.

[0032] 《Base material layer》 The base layer 12 is made of paper. The base layer 12 may be a single layer or a laminate. Examples of paper used as the material for the base layer 12 include tissue paper.

[0033] The thickness of the substrate layer 12 is preferably in the range of 20 μm to 250 μm, taking into consideration factors such as printability and cost.

[0034] 《Picture Layer》 The pattern layer 13 is formed by printing onto the base layer 12 using ink, and is a layer for adding a pattern that gives the decorative sheet an aesthetic appeal.

[0035] As the ink binder, for example, nitrated cotton, cellulose, vinyl chloride-vinyl acetate copolymer, polyvinyl bristyl, 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 13 may 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.

[0036] The ink used to form the pattern layer 13 may further contain, in addition to the binder, colorants such as pigments and dyes, extender pigments, solvents, and various additives, which are typically found in inks. Examples of versatile pigments include condensed azo, insoluble azo, quinacridone, isoindoline, anthraquinone, imidazolon, cobalt, phthalocyanine, carbon, titanium dioxide, iron oxide, mica, and other pearl pigments.

[0037] Concealing layer The opacity layer 19 is provided between the base material layer 12 and the pattern layer 13, and is a layer that provides opacity to the base material to which the decorative sheet 1 is attached. The opacity layer 19 can be made of the same material as the pattern layer 13 described above. The pigment contained in the opacity layer 19 is preferably an opaque pigment, such as titanium dioxide or iron oxide, in order to provide opacity. Furthermore, in order to enhance opacity, it is also possible to add metals such as gold, silver, copper, or aluminum to the material of the opacity layer 19. Generally, flake-shaped aluminum pieces are often added.

[0038] Partial pattern layer The partial pattern layer 14 is partially formed on the surface of the pattern layer 13 and is a layer that assists in adding a pattern to the decorative sheet by displaying a different pattern from the pattern layer 13. The ink used for the partial pattern layer 14 can be made from the same material as described above for the pattern layer 13.

[0039] 《Surface protective layer》 The surface protection layer 15 is formed on the pattern layer 13 and the partial pattern layer 14. Preferably, the surface protection layer 15 covers the entire upper surface of the pattern layer 13 and the partial pattern layer 14. The surface of the surface protection layer 15 is provided with a ridged, protruding uneven structure (uneven portion 15a). The surface protection layer 15 in this embodiment corresponds to the "first protective layer" in the present invention.

[0040] Here, in the decorative sheet 1 according to this embodiment, "ridge-like" refers to a convex shape that is linear in plan view. The shape of the uneven portion 15a in plan view may be curved or straight, but it is preferable that it be curved from the viewpoint of the decorative sheet 1, for example, ease of wiping off fingerprints (fingerprint resistance). The ridge-like protrusions on the surface of the surface protective layer 15 may or may not be branched in plan view.

[0041] Figure 2 is a micrograph of the surface of the surface protection layer 15. As shown in Figure 2, the ridge-like convex shapes of the uneven portion 15a are each curved, and at least some are adjacent in the width direction. At positions where at least some of the convex shapes are adjacent in the width direction, the cross-section of the surface protection layer 15 parallel to this width direction and the thickness direction of the surface protection layer 15 has a wave shape, such as a sinusoidal shape, in the portion where the uneven structure is provided.

[0042] The uneven structure of the surface protective layer 15 has a load length ratio Rmr(10%) of 0.4 to 0.7 at a cutting level of 10%. Preferably, the load length ratio Rmr(10%) is 0.45 to 0.65, and more preferably 0.5 to 0.6.

[0043] The load length ratio Rmr(10%) is the ratio of the load length of the roughness curve at cutting level 10% to the evaluation length. Cutting level 10% is the level where the distance in the depth direction from the highest point of the roughness curve is 10% of the maximum cross-sectional height Rt. When a user lightly touches a textured surface with their finger, their finger touches the portion from the highest point of the protrusion to approximately 10% of the height of the protrusion. Therefore, the load length ratio Rmr(10%) correlates with the amount of contact between the finger and the protrusion when a user lightly touches the textured surface with their finger. The load length ratio Rmr(10%) and the maximum cross-sectional height Rt are surface texture parameters specified in JIS B0601:2013.

[0044] The load length ratio Rmr(10%) is expressed by the following equation 1.

[0045]

number

[0046] The uneven structure of the surface protective layer 15 has a root mean square slope Rdq of 0.15 or more and 0.4 or less. Preferably, the root mean square slope Rdq is 0.2 or more and 0.35 or less, and more preferably 0.25 or more and 0.3 or less.

[0047] The root mean square slope Rdq is the root mean square of the local slope of the roughness curve at a reference length. The root mean square slope Rdq is a parameter that can be used to evaluate the magnitude of the local slope angle. Specifically, the root mean square slope Rdq quantifies the steepness of the convex or concave parts of a surface texture. The root mean square slope Rdq is a surface texture parameter specified in JIS B0601:2013.

[0048] The root mean square slope Rdq is expressed by the following equation 2.

[0049]

number

[0050] The uneven structure is preferably such that the root mean square height Rq is between 2.3 μm and 5.6 μm. Preferably, the root mean square height Rq is between 3 μm and 5 μm, and more preferably between 3.5 μm and 4.5 μm.

[0051] The root mean square height Rq is the root mean square of the vertical coordinate value Z(x) of the roughness curve at a reference length l. The root mean square height Rq is a parameter that can be used to evaluate the height of the protrusions or depressions contained in a surface texture. The root mean square height Rq is a surface texture parameter specified in JIS B0601:2013.

[0052] The root mean square height Rq is expressed by the following equation 3.

[0053]

number

[0054] The thickness of the surface protective layer 15 is preferably 9 μm to 14 μm. More preferably, the thickness of the surface protective layer 15 is 10 μm to 13 μm. If the thickness of the surface protective layer 15 is too small or too large, it becomes difficult to achieve a "cold wood feel." Also, if the thickness of the surface protective layer 15 is too large, it becomes difficult to achieve high fingerprint resistance, high stain resistance, and high scratch resistance. Fingerprint resistance, stain resistance, and scratch resistance will be described later. Here, the thickness of the surface protective layer 15 is determined by observing the cross-section with a scanning electron microscope and averaging 25 points. Specifically, the thickness of the surface protective layer 15 can be measured by the following method.

[0055] (Thickness of the surface protective layer) The decorative sheet 1 is embedded in a resin such as a cold-curing epoxy resin or a UV-curing resin and allowed to cure completely. Then, the sheet is cut so that the cross-section of the decorative sheet 1 is exposed, and the measurement surface is obtained by mechanical polishing. Subsequently, the thickness of the surface protective layer is measured using a scanning electron microscope (for example, a SIGMA500 scanning electron microscope manufactured by Carl Zeiss Microscopy).

[0056] Length measurements will be taken at 25 arbitrary points, and the average length value obtained from these 25 points will be defined as the "thickness of the surface protective layer." The measurement conditions will be an acceleration voltage of 0.5 keV (low acceleration voltage), SE2 mode for imaging, and a magnification of 2000x. Sputtering will not be performed on the measurement sample.

[0057] Furthermore, if the coating liquid for the surface protection layer, described later, does not contain a solvent, the thickness of the coating film made from the coating liquid for the surface protection layer will be equal to the thickness of the surface protection layer 15.

[0058] The surface protective layer 15 preferably includes a cured resin and particles. The resin contained in the surface protective layer 15 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.

[0059] The amount of cured ionizing radiation-curable resin in the surface protective layer 15 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.

[0060] 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.

[0061] The acrylate is preferably a three-functional or more-functional acrylate, and more preferably a four-functional or more-functional acrylate. In order to obtain a surface protective layer 15 with excellent scratch resistance, it is preferable that the acrylate has three or more functional groups. There is no upper limit to the number of functional groups in the acrylate, but one example suggests it is four-functional or less.

[0062] The acrylate preferably contains a repeating structure. This repeating structure is preferably 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.

[0063] The number of repetitions of the repeating structure is preferably 9 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 second 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. Also, when an acrylate with a high number of repetitions is used, the gloss value tends to decrease, and the aesthetic appeal tends to improve. However, increasing the number of repetitions reduces the crosslinking density, which reduces the scratch resistance of the surface protective layer. Also, when an acrylate with a low number of repetitions is used, it may be difficult to achieve high processability.

[0064] In a preferred embodiment, the ionizing radiation-curable resin is a trifunctional acrylate containing a repeating structure. The trifunctional acrylate containing a repeating structure 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 structure, the number of repetitions of the repeating structure is preferably 9 or more and 15 or less.

[0065] 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 20 or more and 25 or less.

[0066] 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.

[0067] The particles included in the surface protection layer 15 can 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. When the surface protection layer 15 contains particles, a cool, woody feel can be easily obtained when pressing a finger against the surface of the decorative sheet 1 and sliding a finger across the surface.

[0068] The particles have an average particle size (D50) of 3 μm or more and 3 μm or more and 11 μm or less, preferably 3 μm or more and 8 μm or less. The average particle size of the particles is not particularly limited as long as it is within the above range, but if it is smaller than the thickness of the surface protective layer 15, it is possible to prevent the particles from falling off.

[0069] When the surface protective layer 15 contains particles, wrinkles can be generated more uniformly on the coating surface in the second irradiation step described later. When the average particle size (D50) is large, there is a tendency for the user to feel the unevenness of the particles more strongly. For this reason, if the average particle size (D50) is too large, it becomes difficult to achieve the "cold wood feel". Also, when the average particle size (D50) is large, the particles are more likely to fall off the surface protective layer 15, which may make it difficult to achieve high scratch resistance. Furthermore, if the particles are small, the effect of generating wrinkles uniformly tends to be small. Also, if the particles are small, it becomes difficult to give the cold wood feel.

[0070] Here, "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 15 obtained from this coating liquid will also contain particles. The average particle size of the particles contained in the surface protection layer 15 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 15.

[0071] The particles are preferably included in the surface protective layer 15 in an amount of 3 to 11 parts by mass per 100 parts by mass of resin. More preferably, the amount of particles added is 4 to 8 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.

[0072] When the amount of added particles is within the above range, wrinkles can be generated more uniformly on the surface of the coating in the second irradiation step described later. As a result, the gloss level decreases, and the aesthetic appeal is improved.

[0073] When a large amount of particles are added, the particles are more likely to fall off the surface protective layer 15, making it difficult to achieve high scratch resistance. Also, when a large amount of particles are added, it may be difficult to achieve high stain resistance. Furthermore, when a small amount of particles are added, the effect of uniformly creating wrinkles tends to be reduced. For this reason, when a small amount of particles are added, it may be difficult to achieve a "cold wood feel." In this embodiment, since the amount of particles added can be reduced compared to the conventional technology, it is expected that the decrease in scratch resistance and stain resistance associated with the addition of gloss adjusters can be suppressed.

[0074] The gloss of the surface protective layer 15 is preferably less than 10.0. The gloss of the surface protective layer 15 is preferably 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.

[0075] <Manufacturing method for decorative sheets> The decorative sheet 1, as described with reference to Figure 1, is manufactured, for example, by the following method. Here, for simplification, the base layer 12, the concealing layer 19, the pattern layer 13, and the partial pattern layer 14 are omitted.

[0076] (Preparation of coating solution for surface protection layer) First, a coating liquid for the surface protective layer is prepared and stirred. The coating liquid for the surface protective layer contains, for example, the resin and particles mentioned above. Here, it is assumed that the main component of the resin precursor is acrylate. With a normal stirring method, the particles may appear to be uniformly mixed at first glance, but due to particle aggregation, etc., the dispersion of particles may become uneven in the microscopic region. In this case, wrinkles are less likely to form uniformly on the surface of the surface protective layer 15. In this case, the load length ratio Rmr (10%) of the uneven structure tends to be small. By stirring the coating liquid for the surface protective layer more vigorously or for a longer period compared to a normal stirring method, the above-mentioned unevenness can be eliminated. In this case, the load length ratio Rmr (10%) can be increased.

[0077] In other words, if the load length ratio Rmr(10%) of the resulting uneven structure is smaller than the target value as a result of the manufacturing method for the decorative sheet, the load length ratio Rmr(10%) can be brought closer to the target value by changing the stirring conditions of the coating liquid for the surface protective layer and stirring it more strongly or for a longer period of time.

[0078] 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 15 with low gloss can be formed without gloss modifiers (matte additives).

[0079] In the third 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.

[0080] (Formation of coating film) Next, a coating film consisting of a surface protective coating liquid is formed on one surface of the substrate layer 12. 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.

[0081] (1st irradiation step) After forming a coating film consisting of a surface protective coating liquid, a first irradiation step is performed. In the first irradiation step, light with a wavelength of approximately 200 nm to 400 nm (hereinafter referred to as the first radiation) is irradiated onto the coating film. This partially hardens the coating film. By partially hardening the coating film through the first irradiation step, the wrinkled uneven structure (texture) produced by the second irradiation step described later can be uniformly generated. Alternatively, by appropriately setting the irradiation conditions of the first irradiation step, it is possible to adjust the uneven structure, particularly the depth of the uneven structure.

[0082] As the light source used in the first irradiation step, for example, a high-pressure mercury lamp, a metal halide lamp, and a single-wavelength LED lamp having light with a wavelength of 200 nm to 400 nm can be selected and used.

[0083] The integrated light intensity in the first irradiation process is 2 mJ / cm². 2 More than 100mJ / cm 2 The following is preferable: 10 mJ / cm² 2 More than 80mJ / cm 2 It is more preferable to set it to the following: 20 mJ / cm² 2 More than 60mJ / cm 2 The following is even more preferable: If the cumulative light intensity is reduced, the effect of the first irradiation step described above will not be observed. If the cumulative light intensity is increased, the coating film will fully harden, and wrinkles will not be formed in the subsequent second irradiation step.

[0084] (Second irradiation process) Next, the second irradiation process is carried out. In the second irradiation process, light with a wavelength of 200 nm or less (hereinafter referred to as the second radiation) is irradiated onto the coating film. The ionizing radiation-curable resin contained in the surface protective layer coating liquid has a large absorption coefficient for the second irradiation light. Therefore, the second irradiation light incident on the coating film can only reach a distance of several tens to several hundreds of nanometers from its outermost surface. Consequently, in the second irradiation process, the crosslinking reaction proceeds in the surface region of the coating film, forming an extremely thin cured film, while in other regions, the crosslinking reaction does not proceed and the film remains semi-cured.

[0085] The coating film after the second irradiation step has wrinkles on its surface corresponding to the aforementioned uneven portion 15a. The inventors believe the reason why wrinkles form on the coating film surface due to the second irradiation step is as follows.

[0086] As described above, the second 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 due to irradiation with the second radiation occurs only at the surface of the coating film, and in regions further away from the outermost surface than tens to hundreds of nanometers, some areas remain uncured, and highly fluid molecules exist there. These highly fluid molecules swell the cured film, increasing its volume. As a result, it is thought that the cured film buckles in response to the in-plane compressive stress caused by the increase in volume in the in-plane direction, resulting in wrinkles on the surface of the coating film.

[0087] Furthermore, the inventors believe that the reason why a surface protective layer 15 having surface properties characterized by the above-mentioned parameters can be obtained by the above method is as follows.

[0088] As described above, when a coating film made of a surface protective coating liquid is irradiated with a second radiation, a hardened film is formed on its surface, and the hardened film increases in volume in the in-plane direction, causing wrinkles to form on the surface of the coating film. Since the second radiation is usually irradiated from a vertical direction, the increase in volume of the hardened film in the in-plane direction is greater in areas with a nearly horizontal surface compared to areas with an inclined surface. That is, at the tops of convex parts and the bottoms of concave parts, the rate of increase in volume of the hardened film in the in-plane direction is greater than in other parts.

[0089] Furthermore, during the process of creating this wrinkle shape, mass migration occurs within the coating film from areas corresponding to the recesses of the wrinkles to areas corresponding to the protrusions of the wrinkles. As a result, the thickness of the coating film decreases in the recessed areas and increases in the protruding areas. If the coating film is irradiated with the first radiation prior to the second radiation, the mass migration within the coating film due to the in-plane volume increase of the hardened film becomes gentler. In other words, if the coating film is irradiated with the first radiation, deformation of the coating film surface due to irradiation with the second radiation becomes less likely compared to cases where the first radiation irradiation is omitted. However, in areas with greater thickness, deformation is more likely to occur compared to areas with less thickness because there is a larger amount of material that can contribute to deformation.

[0090] Thus, in the convex areas, the rate of increase in the in-plane volume of the hardened film is large, and deformation is more likely to occur. Therefore, if irradiation with the second radiation is continued, the ridge-like convex areas formed on the surface of the coating film expand so that the portion of the cross-section perpendicular to its length that corresponds to the surface of the coating film becomes, for example, a convex curve, and its width also increases.

[0091] As the convex portions expand to have the cross-sectional shape described above, and the distance between the convex portions shortens, the amount of light from the second radiation reaching the concave portions decreases. Therefore, in the concave portions, the rate of increase in the in-plane volume of the hardened film decreases.

[0092] As a result, an uneven structure is formed that has characteristics such as a gentle slope near the top of the protrusions. In other words, it is considered that a surface protective layer 15 having surface properties characterized by the above-mentioned parameters is obtained.

[0093] Furthermore, the uniformity of particle distribution within the coating film affects the uniformity of distribution in convex and concave areas, and therefore affects the surface properties of the surface protective layer 15. Accordingly, the above method eliminates the non-uniformity of particle dispersion by stirring the coating liquid for the surface protective layer more strongly or for a longer period compared to a normal stirring method.

[0094] The second 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, it emits light in a wavelength range specific to that excimer state.

[0095] The gas used in the excimer lamp may be any of the gases conventionally used as long as it emits light of 200 nm or less. As the gas, noble gases such as Xe, Ar, Kr, or a mixed gas of a noble gas and a halogen gas such as ArBr, ArF, etc. can be used. The excimer lamp has different wavelengths (central wavelengths) depending on the gas, for example, wavelengths such as about 172 nm (Xe), about 126 nm (Ar), about 146 nm (Kr), about 165 nm (ArBr), about 193 nm (ArF), etc.

[0096] Considering the magnitude of the photon energy and the difference between the wavelength and the bonding energy of the organic substance, 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 equipment maintenance and the availability of materials, etc., it is preferable to use a xenon lamp as the light source.

[0097] The second irradiation step is performed in an atmosphere with a low oxygen concentration. Oxygen has a large absorption coefficient for light of 200 nm or less. Therefore, the second irradiation step is preferably performed, for example, in a nitrogen gas atmosphere. The oxygen concentration in the gas phase in the second irradiation step, that is, the residual oxygen concentration in the reaction atmosphere, is preferably 2000 ppm or less, and more preferably 1000 ppm or less.

[0098] Also, 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 protection layer 15.

[0099] The integrated light amount of the second radiation is preferably 0.5 mJ / cm 2 or more and 200 mJ / cm 2 or less, more preferably 1 mJ / cm 2 or more and 100 mJ / cm 2 or less, still more preferably 3 mJ / cm 2 or more and 50 mJ / cm 2 or less, and even more preferably 5 mJ / cm 2 or more and 30 mJ / cm 2The following is most preferable: Reducing the integrated light intensity reduces the in-plane expansion of the cured film. Increasing the integrated light intensity deteriorates the surface condition of the coating film.

[0100] (Third irradiation step) After the second irradiation process is completed, the third irradiation process is carried out. In the third irradiation process, the coating film is irradiated with a third radiation to harden the entire coating film. This results in obtaining a surface protective layer 15.

[0101] The third type of radiation is either ionizing radiation such as electron beams, or ultraviolet radiation with a longer wavelength compared to the first type of radiation.

[0102] The cumulative light intensity of the third type of radiation is 10 mJ / cm². 2 More than 500mJ / cm 2 Preferably, it should be 50 mJ / cm 2 More than 400mJ / cm 2 It is more preferable to use the following: 100 mJ / cm² 2 More than 300mJ / cm 2 The following is even more preferable.

[0103] The decorative sheet 1 can be manufactured, for example, by the method described above. The decorative sheet 1 may also be manufactured by other methods. For example, a plate may be formed for the surface protective layer 15 using the method described above, and the surface protective layer 15 having an uneven surface structure may be formed by transfer using this plate.

[0104] <Effects> The decorative sheet 1 has a surface protective layer 15 that has the surface properties described above. When the pattern layer 13 of such a decorative sheet 1 has a wood grain pattern, when a user presses the surface of the surface protective layer 15 with their skin and slides their skin across the surface, for example, when a user presses the surface of the surface protective layer 15 with their finger and slides their finger across the surface, the decorative sheet 1 gives the user a "cold woody feel." Such a decorative sheet 1 is not only low-gloss and aesthetically pleasing, but also has excellent tactile properties. The following describes this tactile property.

[0105] In the decorative sheet 1 described above, the load length ratio Rmr (10%) of the uneven structure of the surface protective layer 15 is within the range described above. Therefore, when a user lightly touches the uneven structure with their finger, the contact area between the finger and the protrusions is relatively large. Also, normally, when the decorative sheet 1 is placed at room temperature, the surface temperature of the decorative sheet 1 is lower than the user's body temperature. Therefore, when a user touches the decorative sheet 1 with their finger, the user's heat is easily conducted to the decorative sheet 1, giving the decorative sheet 1 a cool tactile sensation to the user.

[0106] Furthermore, the decorative sheet 1 described above has a root mean square slope Rdq of the uneven structure within the range described above. Also, the decorative sheet 1 described above has a root mean square height Rq of the uneven structure within the range described above. The protrusions forming such an uneven structure are moderately steep and have a moderate size in the height direction. Therefore, when a user slides their finger across the surface of the protective layer 15, the decorative sheet 1 stimulates the user's finger, giving the user a moderately rough tactile sensation, that is, a wood-like tactile sensation.

[0107] Thus, when the load length ratio Rmr (10%) of the uneven structure is within the range described above, the decorative sheet 1 gives the user a cool touch, and when the root mean square slope Rdq and root mean square height Rq of the uneven structure are within the range described above, the decorative sheet 1 gives the user a wood-like touch. For this reason, the decorative sheet 1 gives the user a tactile sensation that integrates these two sensations, namely, a "cool woody touch."

[0108] Furthermore, when the frequency of irregularities in an uneven structure is similar, an uneven structure with steeply shaped peaks has a smaller load length ratio Rmr(10%) than an uneven structure with gently shaped peaks. In this case, it is possible to distinguish between the two using only the load length ratio Rmr(10%) parameter. On the other hand, an uneven structure with steeply shaped peaks and a high frequency of irregularities may have a similar load length ratio Rmr(10%) to an uneven structure with gently shaped peaks and a low frequency of irregularities. In this case, it is not possible to distinguish between the two using only the load length ratio Rmr(10%) parameter. In other words, the load length ratio Rmr(10%) parameter alone cannot express that the protrusions of an uneven structure are moderately steep and of a moderate size in the height direction (i.e., giving the user a wood-like tactile sensation). Therefore, it is appropriate to use the load length ratio Rmr (10%) in combination with the root mean square slope Rdq as a parameter to express the "cold feel of wood." Furthermore, it is preferable to combine this with the root mean square height Rq as a parameter to express the "cold feel of wood."

[0109] Since the surface protective layer 15 of the decorative sheet 1 has the surface properties described above, it can achieve a low gloss level even without containing a gloss adjuster (matte additive). Because gloss adjusters reduce the oil repellency of the layer formed by the resin material, the surface protective layer 15 containing a gloss adjuster is prone to fingerprints. The surface protective layer 15 without a gloss adjuster does not easily absorb oil, so fingerprints are less likely to adhere to it. In addition, the surface protective layer 15 with excellent oil repellency is less likely to cause oil stains or the adsorption of contaminants. Furthermore, when the surface of the surface protective layer 15 without a gloss adjuster is scratched, the particles of the gloss adjuster do not fall off, and therefore, the decorative sheet 1 containing such a surface protective layer 15 is less likely to experience changes in gloss or scratches.

[0110] Furthermore, as mentioned above, the surface protection layer 15 can achieve a low gloss level. In this case, the reflection of external light onto the surface of the surface protection layer 15 can be reduced. Therefore, for example, if the pattern layer 13 has a wood grain pattern, the wood grain pattern can be clearly seen. In this case, it is particularly easy to give the user the "feel of cool wood." It should be noted that while the above parameters are related to low gloss, other parameters are also involved in achieving low gloss. For this reason, a low-gloss decorative sheet does not necessarily meet the requirements of the above parameters.

[0111] Furthermore, it is believed that the surface protective layer 15 having the above-described surface properties can be obtained by the method described above for the following reasons in addition to those explained above.

[0112] In the second irradiation step, 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 second irradiation step, the relationship between the distance from the coating film surface and the progress of the crosslinking reaction can be changed.

[0113] When this relationship changes, the thickness of the cured film formed on the surface of the coating by the second 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 light intensity in the first and second irradiation processes 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 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.

[0114] When this relationship changes, the thickness of the cured film formed on the surface of the coating by the second 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 light intensity in the first and second irradiation processes 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 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.

[0115] Therefore, by appropriately setting, for example, the stirring method of the coating liquid for the surface protective layer, 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 second irradiation step, and the cumulative light intensity during the first and second irradiation steps, a surface protective layer with desired surface properties can be obtained. This makes it possible to create a decorative sheet that reproduces the texture (gloss, coolness, feel) of the real material while being highly durable.

[0116] [Second Embodiment] Figures 3-6 are schematic diagrams showing the decorative sheet of the second embodiment, and are cross-sectional views corresponding to Figure 1. In the following description, components common to the first embodiment are denoted by the same reference numerals, and detailed descriptions are omitted.

[0117] The decorative sheet 2A shown in Figure 3 has a base layer 12, an opacity layer 19, a pattern layer 13, a partial pattern layer 14, and a surface protection layer 25A.

[0118] 《Surface protective layer》 The surface protective layer 25A comprises a first protective layer 26 and a second protective layer 27.

[0119] 《1st protective layer》 The first protective layer 26 is formed on the pattern layer 13 and the partial pattern layer 14, and covers the surfaces of the pattern layer 13 and the partial pattern layer 14. Preferably, the first protective layer 26 covers the entire upper surface of the pattern layer 13 and the partial pattern layer 14. The gloss of the first protective layer 26 is lower than the gloss of the second protective layer 27, which will be described later, and the difference in gloss is preferably 5 or more.

[0120] The first protective layer 26 has a surface with an uneven structure (uneven portion 26a) similar to that of the surface protective layer 15 in the first embodiment. The first protective layer 26 can be manufactured in the same manner as the surface protective layer 15 in the first embodiment.

[0121] 《Second protective layer》 The second protective layer 27 is formed to cover a portion of the surface of the first protective layer 26. As shown in Figure 3, the second protective layer 27 of the decorative sheet 2A can cover the upper surface of the first protective layer 26 without overlapping with the partial pattern layer 14 when the decorative sheet 2 is viewed in the thickness direction (plan view). That is, in the surface protective layer 25A, the area where the first protective layer 26 is exposed from between the second protective layer 27 and the partial pattern layer 14 overlap precisely. In this specification, this positional relationship is referred to as "synchronized". Furthermore, "exposed" means that the layer is located at the uppermost layer in a plan view and its surface is exposed.

[0122] The second protective layer 27 is made of a material (resin) that is transparent or translucent enough to allow the pattern of the pattern layer 13 to be seen through. For example, a thermosetting resin is preferred as the material for the second protective layer 27. As the thermosetting resin, for example, considering the deformation-following ability and scratch resistance of the decorative sheet 2A, it is preferable to use a thermosetting resin (binder) having a urethane bond, such as a two-component curing urethane resin. Here, no gloss adjusters such as silica particles are added to the second protective layer 27.

[0123] The decorative sheet 2B shown in Figure 4 has a base layer 12, an opacity layer 19, a pattern layer 13, a partial pattern layer 14, and a surface protection layer 25B. The surface protection layer 25B has a first protection layer 26 and a second protection layer 27.

[0124] Unlike surface protective layer 25A, in surface protective layer 25B, the second protective layer 27 is positioned to overlap exactly with the partial pattern layer 14 in a plan view. In other words, in surface protective layer 25B, the area where the second protective layer 27 is exposed is synchronized with the partial pattern layer 14.

[0125] The decorative sheet 3A shown in Figure 5 has a base layer 12, an opacity layer 19, a pattern layer 13, a partial pattern layer 14, and a surface protection layer 35A.

[0126] The surface protective layer 35A comprises a first protective layer 36 and a second protective layer 37. The first protective layer 36 can be formed using the same material as the first protective layer 26. The second protective layer 37 can be formed using the same material as the second protective layer 27.

[0127] The second protective layer 37 of the surface protective layer 35A is formed on the pattern layer 13 and the partial pattern layer 14, and covers the surfaces of the pattern layer 13 and the partial pattern layer 14.

[0128] The first protective layer 36 is formed to cover a portion of the surface of the second protective layer 37. As shown in Figure 3, in the surface protective layer 35A, the region where the second protective layer 37 is exposed between the first protective layer 36 and the partial pattern layer 14 are in sync.

[0129] The decorative sheet 3B shown in Figure 6 has a base layer 12, an opacity layer 19, a pattern layer 13, a partial pattern layer 14, and a surface protection layer 35B.

[0130] Unlike surface protective layer 35A, in surface protective layer 35B, the first protective layer 36 is positioned to overlap exactly with the partial pattern layer 14 in a plan view. In other words, in surface protective layer 35B, the area where the first protective layer 36 is exposed is synchronized with the partial pattern layer 14.

[0131] In decorative sheets 2A, 2B, 3A, and 3B having such a surface protective layer, a difference in gloss is generated between the position of the surface protective layer that is synchronized with the partial pattern layer 14 and the surrounding area. Therefore, in addition to the effect of decorative sheet 1 of the first embodiment, the difference in gloss makes the partial pattern layer 14 stand out, giving the decorative sheet a visually three-dimensional effect.

[0132] In decorative sheets 2A, 2B, 3A, and 3B, the partial pattern layer 14 and a portion of the surface protection layer are formed in a position that is synchronized in a plan view. In the decorative sheet of the second embodiment, since the base layer 12 is made of paper, the pattern layer 13, the partial pattern layer 14, and the surface protection layer can be formed continuously using printing technology. Furthermore, when forming the surface protection layer, shrinkage is smaller compared to resin film, allowing for suitable alignment. [Examples]

[0133] Examples of the present invention are described below.

[0134] <Example 1> The decorative sheet 1, as described with reference to Figure 1, was manufactured by the following method. Basis weight: 30 g / m² 2 Using a nitrocellulose-based gravure printing ink, an opacity layer, a pattern layer, and a partial pattern layer were printed onto the surface of the tissue paper using a gravure printing press. Subsequently, the surface protective coating liquid 1 described below was continuously applied to cover the pattern layer and the partial pattern layer, forming a coating film with a thickness of 11.58 μm. (Coating liquid 1 for surface protection layer) ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 15 molar added) Product Name: SR9035 (manufactured by Sartomer) Blend: 100 parts by mass

[0135] In the first irradiation step, the coating film is exposed to air using a high-pressure mercury lamp to emit ultraviolet light (main wavelength: 365 nm) at an integrated intensity of 50 mJ / cm². 2 The coating was irradiated until it reached a semi-cured state.

[0136] Next, in the second irradiation step, the coating film is subjected to an integrated light intensity of 50 mJ / cm² using a Xe excimer lamp in a nitrogen gas atmosphere with an oxygen concentration of 500 ppm at atmospheric pressure. 2 The irradiation was continued until a wrinkled shape was formed on the surface.

[0137] Next, as a third irradiation step, the coating film was irradiated with ionizing radiation to harden the entire coating film, thereby obtaining the decorative sheet of Example 1.

[0138] <Example 2> The decorative sheet of Example 2 was obtained in the same manner as in Example 1, except that the following was used as the coating liquid 1 for the surface protective layer. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 6 molar addition) Product Name: Miramer M3160 (Manufactured by Miwon) Blend: 100 parts by mass ·particle Product Name: Silysia 250N (Manufactured by Fuji Silysia Chemical Co., Ltd.) Particle size: 5μm Formula: 5 parts by mass

[0139] <Example 3> The decorative sheet 2A, as described with reference to Figure 3, was manufactured by the following method.

[0140] First, a sheet was obtained in the same manner as in Example 1, except that the following was used as the coating liquid 1 for the surface protective layer. ·Ionizing radiation curable resin Type: Ethoxylated pentaerythritol tetraacrylate (EO20 molar added) Blend: 100 parts by mass ·particle Product Name: Silysia 250N (Manufactured by Fuji Silysia Chemical Co., Ltd.) Particle size: 5μm Formula: 5 parts by mass

[0141] Then, a two-component curing urethane resin was partially applied and cured onto the first protective layer of the obtained sheet, so that the coating amount after drying was 5 g / m2, to form a coating film. (Second protective layer) At this time, the positions of the second protective layer and the partial pattern layer were not synchronized.

[0142] <Example 4> Except for aligning the positions of the second protective layer and the partial pattern layer, a decorative sheet of Example 4 with the same configuration as decorative sheet 2B, as described with reference to Figure 4, was obtained in the same manner as in Example 3.

[0143] <Example 5> The decorative sheet 3A, as described with reference to Figure 5, was manufactured by the following method. Basis weight 30g / m 2 Using a nitrocellulose-based gravure printing ink, an opacity layer, a pattern layer, and a partial pattern layer were printed onto the surface of the thin paper using a gravure printing press. Subsequently, a two-component curing urethane resin was applied and cured to cover the entire surface, including the pattern layer and partial pattern layer, so that the coating amount after drying was 5 g / m2, thereby forming a coating film. (Second protective layer) • Two-component curing urethane resin Type: G125 High Matte (manufactured by DIC Graphics Co., Ltd.)

[0144] On the second protective layer, the following surface protective layer solution 1 was applied without coordinating with the partial pattern layer. The thickness of the surface protective layer solution 1 after drying was 11.58 μm. (Coating liquid 1 for surface protection layer) ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 6 molar addition) Product Name: Miramer M3160 (Manufactured by Miwon) Blend: 100 parts by mass ·particle Product Name: Silysia 250N (Manufactured by Fuji Silysia Chemical Co., Ltd.) Particle size: 5μm Formula: 5 parts by mass

[0145] Finally, the surface protective coating liquid 1 was cured in the same manner as in Example 1 to obtain the decorative sheet of Example 5.

[0146] <Example 6> The following was used as the coating liquid 1 for the surface protective layer, and a decorative sheet of Example 6 was obtained in the same manner as in Example 5, except that the first surface protective layer and the partial pattern layer were synchronized, with reference to Figure 6. ·Ionizing radiation curable resin Type: Trimethylolpropane EO-modified triacrylate (EO 15 molar added) Product Name: SR9035 (manufactured by Sartomer) Blend: 100 parts by mass

[0147] <Comparative Example 1> A decorative sheet for Comparative Example 1 was obtained in the same manner as in Example 1, except that the following isocyanate curing agent and main component were used as the coating liquid 1 for the surface protective layer, and 40 parts by mass of general-purpose silica (amorphous) was added thereto. Isocyanate curing agent Type: G125HV (Manufactured by DIC Graphics Co., Ltd.) Main ingredient Type: G-XA (manufactured by DIC Graphics Corporation)

[0148] <Comparative Examples 2-6> Decorative sheets were obtained in the same manner as in Comparative Example 1 by changing the amount of silica added and the thermal conditions.

[0149] <Comparative Example 7> A decorative sheet of Comparative Example 7 was obtained in the same manner as in Example 5, except that the isocyanate curing agent and main component of Comparative Example 1 were used as the coating liquid 1 for the surface protective layer, and 40 parts by mass of general-purpose silica (amorphous) were added thereto.

[0150] <Comparative Examples 8-12> By varying the amount of silica added and the thermal conditions, decorative sheets for Comparative Examples 8 to 12 were obtained in the same manner as in Comparative Example 7.

[0151] <Comparative Example 13> A decorative sheet of Comparative Example 13 was obtained in the same manner as in Example 6, except that the isocyanate curing agent and main component of Comparative Example 1 were used as the coating liquid 1 for the surface protective layer, and 40 parts by mass of general-purpose silica (amorphous) were added thereto.

[0152] <Comparative Examples 14-18> By varying the amount of silica added and the thermal conditions, decorative sheets of Comparative Examples 14-18 were obtained in the same manner as Comparative Example 13.

[0153] The following evaluations were performed on each of the obtained decorative sheets.

[0154] (Rmr,Rdq) The Rmr (10%) and Rdq of the surface protective layer were measured using a SURFTEST SJ-210 (manufactured by Mitutoyo Corporation) according to the method specified in JIS B0601:2013.

[0155] (texture) (1) The coldness of wood In a test where five people touched a decorative sheet, a score of ◎ was given if four or more people felt the coldness of wood, ○ if three people felt it, △ if one or two people felt it, and × if no one felt the coldness of wood. A score of ○ or higher was considered a pass.

[0156] (2) Design A sensory evaluation was conducted by five evaluators. Evaluators visually assessed the decorative sheet, assigning a "○" if three or more people felt it closely resembled the design of real wood, a "△" if one or two people felt it closely resembled real wood, and a "×" if no one felt it closely resembled real wood. A score of △ or higher was considered a pass.

[0157] (durability) (3) How easily fingerprints stick to it The gloss level at 60 degrees was measured on the surface of each decorative sheet, and the resulting gloss level was defined as the initial gloss level. Next, a commercially available high-grade fatty acid was applied to the surface protective layer as an evaluation solution, and the evaluation solution that adhered to the surface of the decorative sheet was wiped off.

[0158] Subsequently, the glossiness at 60 degrees of the area where the evaluation solution was wiped off was measured, and the resulting glossiness was defined as the glossiness after wiping. 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. A score of △ or higher was considered a passing grade. ○: 70% or more and less than 250% △: 50% or more but less than 70%, or 250% or more but less than 300% ×: Less than 50% or 300% or more

[0159] (4) Stain resistance To evaluate stain resistance, a stain test A, as defined by the Japanese Agricultural Standards (JAS), was conducted. 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. Afterward, the lines were wiped off with a cloth soaked in ethanol. The following writing instruments were used to draw the lines: (writing implements) Blue ink: PILOT INK-30 (manufactured by Pilot Corporation) Black quick-drying ink: Magic Ink No. 500 (manufactured by Teranishi Chemical Industry Co., Ltd.) Red crayon: Pentel PTC-T11R (manufactured by Pentel) The evaluation criteria were as follows. A circle (〇) was considered a passing grade. ○: The lines of each color could be easily wiped away. △: Some of the lines of each color were wiped away, but some stains remained. ×: The lines of each color could not be wiped away.

[0160] (5) Scratch resistance Each decorative sheet was attached to a wood substrate using a urethane-based adhesive. Then, the decorative sheet was rubbed back and forth 20 times with steel wool while applying a load of 100g, and any scratches or changes in gloss on the surface of the decorative sheet were visually inspected. The evaluation criteria were as follows. A circle (〇) was considered a passing grade. ○: No scratches or changes in gloss occurred on the surface. △: Minor scratches or changes in gloss have occurred on the surface. ×: Significant scratches or changes in gloss occurred on the surface.

[0161] (6) Chemical resistance Each decorative sheet was attached to a wood substrate using a urethane-based adhesive. Then, 48% ethanol was dropped onto the surface of the decorative sheet and covered with a watch glass. After one hour, the watch glass was removed, the dripped area was wiped with cotton, and the extent of any remaining residue was checked. The evaluation criteria were as follows. A circle (〇) was considered a passing grade. ○: No change in gloss was observed at all, and no whitening phenomenon was confirmed. △: A slight change in gloss was observed, or a slight whitening phenomenon was confirmed. ×: A clear change in gloss was observed, or a significant whitening phenomenon was confirmed.

[0162] (7) Overall evaluation of durability ○: Products that meet the requirements for fingerprint resistance, stain resistance, scratch resistance, and chemical resistance. △: Passed two or three of the four test items. ×: The test was conducted in which one or fewer of the four test items were passed.

[0163] (8) Overall evaluation of texture and durability In the evaluation of tactile feel and durability, items that passed all three criteria (1) the coolness of the wood, (2) the design, and (7) the overall evaluation (of durability) were marked with a circle (○), while items that failed even one criterion were marked with a cross (×), with the items marked with a circle (○) being the final approved products.

[0164] The evaluation results are shown in Tables 1-3.

[0165] [Table 1]

[0166] [Table 2]

[0167] [Table 3]

[0168] [Table 4]

[0169] The evaluation results confirmed that each of the decorative sheets in Examples 1 to 6 was of high quality in terms of texture and durability.

[0170] Based on the above, it has been confirmed that the present invention is useful. [Explanation of Symbols]

[0171] 1,2A,2B,3A,3B…Decorative sheet, 12…Base layer, 13…Pattern layer, 15,25A,25B,35A,35B…Surface protective layer, 14…Partial pattern layer, 26,36…First protective layer, 27,37…Second protective layer, 50…Base material, 100…Decorative material, Rdq…Root mean square slope, Rmr…Load length ratio

Claims

1. A paper-based substrate layer, A pattern layer provided on one surface of the base material layer, A partial pattern layer is provided on the surface of the pattern layer and partially covers the pattern layer, The system comprises a surface protective layer provided on the surface of the pattern layer and the partial pattern layer, covering both surfaces, The surface protection layer has a first protective layer in which at least a portion of the surface is exposed. The first protective layer does not contain a gloss adjuster. The surface of the first protective layer is provided with an uneven structure. The aforementioned uneven structure is a decorative sheet in which the load length ratio Rmr (10%) at a cutting level of 10% is 0.4 or more and 0.7 or less, and the root mean square slope Rdq is 0.15 or more and 0.4 or less.

2. The surface protective layer comprises the first protective layer covering the surface of the pattern layer and the partial pattern layer, It comprises a second protective layer that covers a portion of the surface of the first protective layer and is laminated on the first protective layer, The decorative sheet according to claim 1, wherein the second protective layer has a higher gloss than the first protective layer.

3. The surface protective layer comprises a second protective layer that covers the surface of the pattern layer and the partial pattern layer, The first protective layer is laminated on the second protective layer, covering a portion of the surface of the second protective layer, The decorative sheet according to claim 1, wherein the second protective layer has a higher gloss than the first protective layer.

4. The decorative sheet according to claim 2 or 3, wherein, in a plan view, the area in which the first protective layer is exposed and the partial pattern layer are in sync.

5. The decorative sheet according to claim 2 or 3, wherein, in a plan view, the area where the second protective layer is exposed and the partial pattern layer are in sync.

6. The decorative sheet according to any one of claims 1 to 3, wherein the glossiness of the first protective layer is less than 10.

7. The decorative sheet according to any one of claims 1 to 3, wherein the first protective layer comprises a cured resin and particles.

8. The decorative sheet according to claim 7, wherein the particles have an average particle size of 3 μm or more and 11 μm or less.

9. The decorative sheet according to claim 7, wherein the first protective layer comprises 3 to 11 parts by mass of the particles with respect to 100 parts by mass of the resin.

10. The decorative sheet according to claim 7, wherein the resin is an ionizing radiation-curable resin.

11. The decorative sheet according to claim 7, wherein the precursor of the resin is acrylate.

12. The precursor of the aforementioned resin is a trifunctional acrylate containing a repeating structure. The decorative sheet according to claim 7, wherein the number of repetitions of the repeating structure is 9 or more and 15 or less.

13. The precursor of the aforementioned resin is a tetrafunctional acrylate containing a repeating structure. The decorative sheet according to claim 7, wherein the number of repetitions of the repeating structure is 20 or more and 25 or less.

14. The decorative sheet according to any one of claims 1 to 3, wherein the thickness of the surface protective layer is 9 m or more and 14 μm or less.

15. A decorative sheet according to any one of claims 1 to 3, A base material to which the decorative sheet is attached, A decorative material that has the following features.

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