Decorative sheet and method for manufacturing decorative sheet

Abstract

To provide a decorative sheet with improved weather resistance, and a method for manufacturing a decorative sheet.SOLUTION: A decorative sheet 10 comprises: a colored original fabric layer 1; a pattern printed layer 2 which is provided for an upper side UP of the colored original fabric layer 1; a clear layer 3 which is provided for the upper side UP of the pattern printed layer 2, and has embossment on a surface; and a top coat layer 4 which is provided for the upper side UP of the clear layer 3, where the embossment of the clear layer 3 is embossment formed by an embossed plate having the plate depth of 70 μm or less, and a heat shrinkage rate of the colored original fabric layer 1 in a sheet surface direction is 0.74% or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a decorative sheet and a method for producing a decorative sheet. [Background technology]

[0002] 2. Description of the Related Art Conventionally, decorative sheets used as surface materials for furniture and residential building materials include decorative sheets that have a three-dimensional feel to the touch by forming unevenness (embossment) on the surface by embossing or the like.

[0003] For example, in a wood grain pattern decorative sheet, by imparting a three-dimensional feel to the vascular portion of the wood grain pattern, it is possible to provide a wood grain pattern decorative sheet that more closely resembles the appearance of natural wood.

[0004] An example of an embossed decorative sheet is described in Patent Document 1. The decorative sheet described in Patent Document 1 is a decorative sheet having, in this order, a picture pattern layer, a first adhesive layer, a polyester resin layer, and a surface protective layer on a thermoplastic resin base sheet.

[0005] Moreover, the method for producing a decorative sheet described in Patent Document 1 is characterized in that after a surface protective layer is attached by dry lamination, embossing is carried out.

[0006] The decorative sheet described in Patent Document 1 is embossed after a surface protective layer is attached, and therefore an embossed pattern is formed on the surface of the decorative sheet. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2022-52702 Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the case of decorative sheets whose surfaces are embossed, such as the decorative sheet described in Patent Document 1, the deeper the embossing plate used for the embossing, the greater the risk of air becoming trapped between the layer to be embossed and the layer underneath.

[0009] If air gets mixed in between the layers, the weather resistance of the decorative sheet may deteriorate, particularly when embossing is performed on the upper side of layers laminated by extrusion lamination.

[0010] In light of the above circumstances, an object of the present invention is to provide a decorative sheet with improved weather resistance and a method for producing a decorative sheet. [Means for solving the problem]

[0011] In order to solve the above problems, the present invention proposes the following means. The decorative sheet of the present invention comprises a colored base fabric layer, a pattern printed layer provided on the upper side of the colored base fabric layer, a clear layer provided on the upper side of the pattern printed layer and having an embossed surface, and a top coat layer provided on the upper side of the clear layer, wherein the embossment in the clear layer is formed by an embossing plate having a plate depth of 70 μm or less, and the heat shrinkage rate in the plate surface direction of the colored base fabric layer is 0.74% or less.

[0012] In the decorative sheet, the top coat layer may contain a thermosetting resin, an ultraviolet-curable resin, or an electron beam-curable resin.

[0013] In the decorative sheet, the colored base fabric layer may have a thickness of 40 μm or more and contain a thermoplastic resin.

[0014] In the decorative sheet, the clear layer may have a thickness of 38 μm or more and contain a thermoplastic resin.

[0015] The manufacturing method for the decorative sheet of the present invention includes a pattern printing process for printing a pattern printed layer on the upper side of a colored base layer having a heat shrinkage rate of 0.74% or less in the plate surface direction, a clear layer lamination process for laminating a clear layer on the upper side of the pattern printed layer, an embossing process for forming an embossment on the surface of the clear layer using an embossing plate having a plate depth of 70 μm or less, and a top coat layer lamination process for laminating a top coat layer on the upper side of the clear layer.

[0016] In the method for producing the decorative sheet, the pattern printing step may be such that the pattern printed layer is printed on the upper side of the colored base fabric layer having a thickness of 40 μm or more.

[0017] In the above-mentioned method for producing a decorative sheet, the clear layer laminating step may laminate the clear layer so that the clear layer has a thickness of 38 μm or more. Effect of the Invention

[0018] According to the decorative sheet and method for producing a decorative sheet of the present invention, it is possible to provide a decorative sheet and a method for producing a decorative sheet with improved weather resistance. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a cross-sectional view showing a schematic diagram of a decorative sheet according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view showing a schematic diagram of an embossing plate for embossing the decorative sheet. [Diagram 3] 4 is a flowchart showing an example of a method for producing the decorative sheet. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view that shows a schematic diagram of a decorative sheet 10 according to this embodiment.

[0021] In this embodiment, as shown in Figure 1, the thickness direction of the decorative sheet 10 is defined as the "vertical direction V", the side of the decorative sheet 10 on which the top coat layer 4 is provided is defined as the "upper side UP" in the vertical direction V, and the side opposite the upper side UP is defined as the "lower side LO" in the vertical direction V. In addition, the sheet surface direction of the decorative sheet 10 is defined as the "width direction C". Here, the "sheet surface direction (width direction C)" of the decorative sheet 10 refers to a direction perpendicular to the vertical direction V. For example, when the vertical direction V refers to the vertical direction, the sheet surface direction (width direction C) refers to the horizontal direction.

[0022] The decorative sheet 10 comprises a colored base fabric layer 1, a pattern printed layer 2, a clear layer 3, a top coat layer 4, and a primer layer 5.

[0023] The colored raw fabric layer 1 is a layer provided on the upper side UP of the primer layer 5. Details of the primer layer 5 will be described later. Thermoplastic resins can be used as the colored raw fabric layer 1. For example, polyolefin resins such as polyethylene and polypropylene can be used as the colored raw fabric layer 1. The thickness of the colored raw fabric layer 1 in the vertical direction V is preferably 40 μm or more.

[0024] The heat shrinkage of the colored raw fabric layer 1 is 0.74% or less. Here, the heat shrinkage refers to a dimensional change due to heating (thermal dimensional change) measured in accordance with JIS K 6734. The heat shrinkage refers to the heat shrinkage in the width direction C (sheet surface direction) of the colored raw fabric layer 1, and more specifically, refers to the heat shrinkage in the machine direction of the colored raw fabric layer 1.

[0025] Here, the flow direction refers to the direction (MD: Machine Direction) in which molten resin is flowed in the manufacturing process of the colored raw fabric layer 1. This molten resin is cooled to form the sheet-like colored raw fabric layer 1. A resin sheet such as the colored raw fabric layer 1 is formed into a sheet shape by flowing molten resin at a certain thickness in a specified direction (flow direction) and cooling it, and is often processed and stored by being wound around a roll in the longitudinal direction. Therefore, the flow direction of a resin sheet often refers to the longitudinal direction of the resin sheet.

[0026] The pattern-printed layer 2 is a layer provided on the upper side UP of the colored base fabric layer 1. The pattern-printed layer 2 is formed by printing a pattern such as wood grain, stone grain, or sand grain on the upper side UP of the colored base fabric layer 1. The printing method for the pattern-printed layer 2 can be a known printing method such as gravure printing, offset printing, flexographic printing, silk screen printing, or inkjet printing. For the pattern-printed layer 2, a known printing ink suitable for the printing method to be adopted can be used.

[0027] The clear layer 3 is a layer provided on the upper side UP of the pattern-printed layer 2. A thermoplastic resin can be used for the clear layer 3. For example, a polyolefin resin such as polyethylene or polypropylene can be used for the clear layer 3. It is preferable to use a transparent or semi-transparent material for the clear layer 3 so that the pattern of the pattern-printed layer 2 can be seen through. In addition, it is preferable that the thickness of the clear layer 3 in the vertical direction V is 38 μm or more. The clear layer 3 is formed, for example, by extrusion lamination.

[0028] The surface (upper UP surface) of the clear layer 3 is provided with a concave-convex shape (embossment) formed by pressing an embossing plate against the surface. FIG. 2 is a cross-sectional view that shows a schematic diagram of an embossing plate P for embossing the clear layer 3. As shown in FIG.

[0029] 2, embossments are formed on the surface of the clear layer 3 by pressing the unevenness of an embossing plate P. The plate depth H of the embossing plate P that embosses the clear layer 3 is 70 μm or less.

[0030] Here, the plate depth H of the embossing plate P refers to the height (depth) in the vertical direction V of the projections and recesses of the embossing plate P for forming an embossment in the clear layer 3. For example, a convex shape with a height of 70 μm or less in the vertical direction V is pressed against the clear layer 3 from the upper side UP.

[0031] Due to the convex shape with a height of 70 μm or less, a groove that is concave on the lower side LO along the convex shape of the embossing plate P is formed on the surface of the clear layer 3, forming an embossment (concave-convex shape). In reality, the clear layer 3 deforms slightly after embossing due to elasticity, etc., so that the height of the embossment formed on the clear layer 3 in the vertical direction V differs slightly from the plate depth H of the embossing plate P.

[0032] The top coat layer 4 is a layer provided on the upper side UP of the clear layer 3. For the top coat layer 4, a thermosetting resin, an ultraviolet curing resin, an electron beam curing resin, or a mixture thereof can be used. For example, a urethane resin or an acrylic resin can be used for the top coat layer 4. It is preferable to use a transparent or semi-transparent material for the top coat layer 4 so that the pattern of the pattern-printed layer 2 can be seen through the clear layer 3.

[0033] A known printing method such as gravure printing, offset printing, flexographic printing, silk screen printing, or inkjet printing can be used as a method for laminating the topcoat layer 4. The topcoat layer 4 may also be laminated using a known coating device.

[0034] The primer layer 5 is a layer provided on the lower side LO of the colored raw fabric layer 1. A polyester resin, a urethane resin, an acrylic resin, or the like can be used as the primer layer 5. As a method for laminating the primer layer 5, a known printing method such as gravure printing, offset printing, flexographic printing, silk screen printing, or inkjet printing, or a formation method using a known coating device can be used.

[0035] Next, a description will be given of a method for producing the decorative sheet 10 by a decorative sheet production system. Here, the decorative sheet production system is a system that carries out the production of the decorative sheet 10 according to this embodiment.

[0036] (Step S1) First, the decorative sheet manufacturing system performs step S1 (pattern printing step). In step S1, the decorative sheet manufacturing system prints a pattern on the upper side UP of the colored raw fabric layer 1 to form a pattern-printed layer 2. At this time, the heat shrinkage rate of the colored raw fabric layer 1 is 0.74% or less.

[0037] Next, the decorative sheet manufacturing system performs step S2 (clear layer lamination step). In step S2, the decorative sheet manufacturing system laminates a thermoplastic resin on the upper side UP of the pattern-printed layer 2 by extrusion lamination to form the clear layer 3.

[0038] At this time, the decorative sheet manufacturing system also laminates a primer layer 5 on the lower side LO of the colored raw fabric layer 1.

[0039] Next, the decorative sheet manufacturing system performs step S3 (embossing step). In step S3, the decorative sheet manufacturing system presses an embossing plate P against the surface of the upper side UP of the clear layer 3 formed in step S2, and forms an embossment on the surface of the clear layer 3.

[0040] At this time, the plate depth H of the embossing plate P for embossing the surface of the clear layer 3 is 70 μm or less. Here, since the heat shrinkage rate of the colored base fabric layer 1 is 0.74% or less and the plate depth H of the embossing plate P is 70 μm or less, it is possible to prevent air from being mixed in between the pattern-printed layer 2 and the clear layer 3.

[0041] If air gets mixed in between the pattern-printed layer and the clear coat layer, the surface of the pattern-printed layer may deteriorate, and the weather resistance of the decorative sheet may deteriorate. Also, the more air gets mixed in between the pattern-printed layer and the clear coat layer, the more the weather resistance of the decorative sheet tends to deteriorate.

[0042] By setting the heat shrinkage rate of the colored base layer 1 to 0.74% or less and setting the plate depth H of the embossing plate P to 70 μm or less, it is possible to prevent air from being mixed in between the pattern printed layer 2 and the clear layer 3, thereby improving the weather resistance of the decorative sheet 10.

[0043] After embossing the surface of the clear layer 3, the decorative sheet manufacturing system performs step S4 (topcoat layer lamination process). In step S4, the decorative sheet manufacturing system forms a topcoat layer 4 by laminating a thermosetting resin, an ultraviolet curable resin, an electron beam curable resin, or a mixture thereof on the upper side UP of the embossed clear layer 3, thereby forming the decorative sheet 10.

[0044] The decorative sheet 10 and the manufacturing method for the decorative sheet 10 of this embodiment include a colored base fabric layer 1, a pattern printed layer 2 provided on the upper side UP of the colored base fabric layer 1, a clear layer 3 provided on the upper side UP of the pattern printed layer 2 and having an embossed surface, and a top coat layer 4 provided on the upper side UP of the clear layer 3. The clear layer 3 is embossed by an embossing plate P having a plate depth H of 70 μm or less. The heat shrinkage rate of the colored base fabric layer 1 is 0.74% or less.

[0045] As a result, it is possible to prevent air from being mixed in between the pattern-printed layer 2 and the clear layer 3, and it is possible to provide a decorative sheet 10 and a manufacturing method for the decorative sheet 10 with improved weather resistance.

[0046] Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design modifications and the like within the scope of the present invention are also included. In addition, the components shown in the above-mentioned embodiment and the modified examples shown below can be appropriately combined to form a configuration.

[0047] (Variation 1) In the above embodiment, the decorative sheet 10 includes a primer layer 5, but the embodiment of the decorative sheet 10 is not limited to this. The decorative sheet does not have to include a primer layer 5.

[0048] For example, when a decorative board is formed by attaching a substrate (such as a wood substrate) to the lower LO of the decorative sheet 10, the primer layer 5 is a layer for improving adhesion between the decorative sheet 10 and the substrate attached to the lower LO of the decorative sheet 10. Therefore, if the adhesion between the decorative sheet 10 and the substrate attached to the lower LO of the decorative sheet 10 is sufficient without providing the primer layer 5, the decorative sheet does not need to be provided with the primer layer 5.

[0049] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples.

[0050] Example 1 A 55 μm-thick colored raw fabric layer 1 made of thermoplastic resin was prepared. A pattern was printed on the upper side UP of the colored raw fabric layer 1 by gravure printing to form a pattern-printed layer 2. At this time, the heat shrinkage rate of the colored raw fabric layer 1 in the machine direction was set to 0.74%. The heat shrinkage rate of the colored raw fabric layer 1 was a value measured in accordance with JIS K 6734.

[0051] A clear layer 3 was provided on the upper side UP of the pattern-printed layer 2 by an extruder, and the surface of the upper side UP of the clear layer 3 was embossed with an embossing plate P. At this time, the plate depth H of the embossing plate P for embossing the clear layer 3 was set to 45 μm.

[0052] A primer layer 5 was laminated on the lower side LO of the colored raw fabric layer 1. Furthermore, a top coat layer 4 was laminated on the upper side UP of the clear layer 3, thereby obtaining the decorative sheet 10 of Example 1.

[0053] Example 2 The decorative sheet 10 of Example 2 was obtained in the same manner as in Example 1, except that the plate depth H of the embossing plate P for embossing the clear layer 3 was set to 60 μm.

[0054] Example 3 The decorative sheet 10 of Example 3 was obtained in the same manner as in Example 1, except that the plate depth H of the embossing plate P for embossing the clear layer 3 was set to 70 μm.

[0055] Comparative Example 1 A decorative sheet of Comparative Example 1 was obtained in the same manner as in Example 1, except that the depth of the embossing plate used to emboss the clear layer was 80 μm.

[0056] Comparative Example 2 A decorative sheet of Comparative Example 2 was obtained in the same manner as in Example 1, except that the heat shrinkage rate of the colored raw fabric layer in the machine direction was 1.41%.

[0057] Comparative Example 3 The decorative sheet of Comparative Example 3 was obtained in the same manner as in Example 1, except that the heat shrinkage rate in the machine direction of the colored raw material layer was 1.41% and the depth of the embossing plate used to emboss the clear layer was 60 μm.

[0058] Comparative Example 4 The decorative sheet of Comparative Example 4 was obtained in the same manner as in Example 1, except that the heat shrinkage rate in the machine direction of the colored base layer was 1.41% and the depth of the embossing plate used to emboss the clear layer was 70 μm.

[0059] Comparative Example 5 The decorative sheet of Comparative Example 5 was obtained in the same manner as in Example 1, except that the heat shrinkage rate in the machine direction of the colored base layer was 1.41% and the depth of the embossing plate used to emboss the clear layer was 80 μm.

[0060] Comparative Example 6 A decorative sheet of Comparative Example 6 was obtained in the same manner as in Example 1, except that the heat shrinkage rate of the colored raw fabric layer in the machine direction was 1.89%.

[0061] Comparative Example 7 The decorative sheet of Comparative Example 7 was obtained in the same manner as in Example 1, except that the heat shrinkage rate in the machine direction of the colored base layer was 1.89% and the depth of the embossing plate used to emboss the clear layer was 60 μm.

[0062] Comparative Example 8 The decorative sheet of Comparative Example 8 was obtained in the same manner as in Example 1, except that the heat shrinkage rate in the machine direction of the colored base layer was 1.89% and the depth of the embossing plate used to emboss the clear layer was 70 μm.

[0063] Comparative Example 9 The decorative sheet of Comparative Example 9 was obtained in the same manner as in Example 1, except that the heat shrinkage rate in the machine direction of the colored raw material layer was 1.89% and the depth of the embossing plate used to emboss the clear layer was 80 μm.

[0064] (Experiment 1) The decorative sheets of Examples 1-3 and Comparative Examples 1-9 were evaluated for the presence or absence of air infiltration between the pattern-printed layer and the clear layer. In the evaluation of the presence or absence of air infiltration, the surface of the decorative sheet exposed to oblique light was visually checked to confirm whether air was infiltrated between the pattern-printed layer and the clear layer. The evaluation criteria were three-level, with ◯ being a pass. ◯ (Good): No air was observed between the pattern printed layer and the clear layer. △(Fair): A small amount of air is partially found between the pattern print layer and the clear layer. × (Poor): Air is found to be trapped between the pattern printed layer and the clear layer over the entire surface.

[0065] (Experiment 2) A weather resistance test was carried out on the decorative sheets of Examples 1-3 and Comparative Examples 1-9. The weather resistance test was carried out for 2500 hours using a sunshine weather meter (carbon arc lamp type) in accordance with JIS B 7753. The black panel temperature was set to 63°C ± 3°C. The evaluation criteria were three-level, with ◯ being a pass. ◯ (Good): No change in design due to deterioration of the pattern printing layer is observed. △(Fair): There is a small amount of design change in some areas due to deterioration of the pattern printing layer. × (Poor): Design changes due to deterioration of the pattern printing layer are observed over the entire surface.

[0066] (Experimental Results) The results of Experiments 1 and 2 are shown in Table 1. Table 1 also shows the heat shrinkage rate of the colored base fabric layer and the plate depth of the embossing plate for embossing the clear layer in Examples 1-3 and Comparative Examples 1-9.

[0067] Example 1-3, in which the heat shrinkage rate of the colored base fabric layer 1 was 0.74% or less and the plate depth H of the embossing plate P for embossing the clear layer 3 was 70 μm or less, showed good results in Experiments 1 and 2. That is, in Example 1-3, no air was found to be mixed in between the pattern-printed layer 2 and the clear layer 3, and no design change due to deterioration of the pattern-printed layer 2 was found in the weather resistance test.

[0068] Comparative Examples 3 and 6 showed good results in Experiment 1, but failed in Experiment 2. This is thought to be due to the inclusion of minute air particles that cannot be seen with the naked eye between the pattern-printed layer and the clear layer, which caused the samples to fail Experiment 2.

[0069] [Table 1] [Explanation of symbols]

[0070] 10 Decorative Sheet 1 Colored original fabric layer 2 pattern printing layers 3 Clear layer 4 Topcoat Layer 5 Primer layer P embossed version H Embossing depth V vertical direction UP upper side LO Lower C Width direction (board surface direction)

Claims

1. A colored base layer; A pattern printed layer provided on the upper side of the colored base fabric layer; A clear layer provided on the upper side of the pattern printed layer and having an embossed surface; A topcoat layer provided on the upper side of the clear layer; Equipped with The embossment of the clear layer is an embossment formed by an embossing plate having a plate depth of 70 μm or less, The heat shrinkage rate of the colored raw layer in the plate surface direction is 0.74% or less. Decorative sheet.

2. The topcoat layer contains a thermosetting resin, an ultraviolet curable resin, or an electron beam curable resin. The decorative sheet according to claim 1 .

3. The colored base layer is The thickness is 40 μm or more, Including thermoplastic resins, The decorative sheet according to claim 1 .

4. The clear layer is The thickness is 38 μm or more, Including thermoplastic resins, The decorative sheet according to any one of claims 1 to 3.

5. A pattern printing process of printing a pattern printing layer on the upper side of a colored base layer having a heat shrinkage rate of 0.74% or less in the plate surface direction; A clear layer lamination process of laminating a clear layer on the upper side of the pattern printed layer; an embossing step of forming an embossment on the surface of the clear layer using an embossing plate having a plate depth of 70 μm or less; a topcoat layer lamination step of laminating a topcoat layer on the upper side of the clear layer; Equipped with A method for producing a decorative sheet.

6. The pattern printing step includes printing the pattern printing layer on the upper side of the colored base fabric layer having a thickness of 40 μm or more. A method for producing the decorative sheet according to claim 5.

7. The clear layer lamination step includes laminating the clear layer so that the thickness of the clear layer is 38 μm or more. A method for producing the decorative sheet according to claim 5 or 6.

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