Decorative sheet and method for manufacturing decorative sheet

Abstract

To provide a decorative sheet on which a pattern layer is formed by an inkjet printing method, the decorative sheet having further improved designability.SOLUTION: A decorative sheet 10 includes a first layer (base material 1) and a pattern layer 2 formed on a surface 1a of the first layer (base material 1) by an inkjet printing method. An arithmetic average height Sa of surface roughness of the surface of the first layer on which the pattern layer 2 is formed falls within a range of 50 μm or more and 300 μm or less.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a decorative sheet having a design property and used for forming a covering material or the like, and to a method for producing the decorative sheet. [Background technology]

[0002] An example of a decorative sheet is the covering material described in Patent Document 1. Patent Document 1 describes a decorative sheet in which a design layer is laminated on the surface of a base substrate, and describes that the design layer is formed by an inkjet printing method. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-163791 A Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, when a design layer is formed by inkjet printing, the surface of the substrate to be printed is flat, and ink ejected from an inkjet head regularly hits the flat substrate surface to form the design layer.

[0005] That is, when the substrate has a surface with large irregularities (see FIG. 4(b)), the ink 21 that lands regularly may be buried in the irregularities of the substrate, resulting in an unstable pattern that may not be the desired pattern. This adversely affects the design of the decorative sheet. The present invention has been made in view of the above-mentioned points, and has as its object to further improve the design of a decorative sheet in which a pattern layer is formed by an inkjet printing method. [Means for solving the problem]

[0006] In order to improve the design of decorative sheets, the inventors conducted extensive research into how to simultaneously improve the design by imparting unevenness to the surface on which the picture layer is formed, and provide a stable picture layer when inkjet decoration is performed on a surface with unevenness, and thus developed the present invention.

[0007] In order to solve the problem, one aspect of the present invention is a decorative sheet comprising a first layer and a pattern layer formed on a surface of the first layer by an inkjet printing method, wherein the arithmetic mean height Sa of the surface roughness of the first layer on which the pattern layer is formed is in the range of 50 μm or more and 300 μm or less.

[0008] Here, it is impossible or impractical to analyze and identify the structure or properties of a design layer formed by inkjet printing based on measurements, and therefore the design layer is identified by the description "design layer formed by inkjet printing." Effect of the Invention

[0009] According to the aspect of the present invention, it is possible to provide a stable pattern layer while improving the design by imparting unevenness to the pattern-forming surface. As a result, according to the aspect of the present invention, it is possible to stably improve the design of the decorative sheet. [Brief description of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view showing a configuration of a decorative sheet in an embodiment of the present invention. [Diagram 2] FIG. 11 is a cross-sectional view showing a configuration of a modified example of the present invention. [Diagram 3] FIG. 11 is a cross-sectional view showing a configuration of a modified example of the present invention. [Figure 4] FIG. 1 is a schematic diagram showing the relationship between the pattern layer forming surface 1a and the ink 21 deposited by inkjet printing, where (a) is an example of a flat surface, (b) is an example of a surface with significant irregularities, and (c) is an example of a surface based on the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals, and duplicated descriptions are omitted. Each drawing is schematic and may differ from the actual one. The following embodiments are examples of devices and methods for embodying the technical idea of ​​the present technology, and the technical idea of ​​the present technology is not limited to the devices and methods exemplified in the following embodiments. The technical idea of ​​the present technology can be modified in various ways within the technical scope described in the claims. In addition, the directions of "left and right" and "up and down" in the following description are merely definitions for the convenience of explanation and do not limit the technical idea of ​​the present invention. Therefore, for example, if the paper is rotated 90 degrees, "left and right" and "up and down" are read interchangeably, and of course, if the paper is rotated 180 degrees, "left" becomes "right" and "right" becomes "left".

[0012] (composition) The decorative sheet 10 of this embodiment comprises a base substrate 1 and a design layer 2, as shown in FIG.

[0013] (Base material 1) The base substrate 1 constitutes the first layer. The material of the base substrate 1 is not particularly limited, and any known printing medium can be used. Examples of the base substrate 1 include paper substrates, plastic substrates, glass substrates, fabric substrates, substrates made by blending inorganic materials such as fine aggregates with organic resins and forming them into sheets, etc. Paper substrates include fine paper, coated paper, art paper, cast paper, synthetic paper, paper for inkjet printing, etc. Plastic substrates are substrates made of resins such as polyvinyl chloride, polyethylene terephthalate (PET), polypropylene (PP), polyethylene (PE), nylon (registered trademark), polystyrene, styrofoam, polymethyl methacrylate (PMMA), polycarbonate, etc.

[0014] The base substrate 1 is not limited to being made of only one type of substrate, but may be made by laminating two or more types of substrates. The shape of the base material 1 is not particularly limited, and may be, for example, a film, a sheet, a plate, or the like. Considering inkjet printing, a resin-based substrate is preferable for the base substrate 1. Resin-based substrates also include substrates obtained by spraying a resin onto the surface of a paper substrate and then drying it.

[0015] In this embodiment, the upper surface 1a of the base substrate 1 is assumed to be a flat surface, and the design is imparted by forming projections and recesses on the flat surface. However, in this embodiment, the arithmetic mean height Sa of the surface roughness of at least the surface on which the pattern layer 2 is formed of the upper surface of the base substrate 1 is adjusted to be in the range of 50 μm to 300 μm.

[0016] <Pattern layer 2> The pattern layer 2 is formed on the upper surface 1a of the base substrate 1. Specifically, in Fig. 1, the pattern layer 2 is laminated on the surface 1a of the base substrate 1, and is formed so as to cover the entire surface of the base substrate 1. Depending on the pattern to be formed, there may be some exposed portions of the base substrate 1.

[0017] The design layer 2 of this embodiment is formed by using an inkjet printing method. As the ink used in the inkjet printing method, various inks such as water-based, solvent-based, UV-based, etc. can be used. The ink system can be appropriately selected depending on the type of the base substrate 1 to be printed. From the viewpoint of printing on the uneven surface of the substrate, the ink used in the inkjet printing method is preferably a UV-based ink.

[0018] The ink components include a pigment and a dispersant as coloring agents, or a dye as a coloring agent, and it is possible to use a pigment or a dye depending on the color of the ink to be used. Examples of pigments that can be suitably used include inorganic pigments, organic pigments, and black pigments.

[0019] Examples of inorganic pigments that can be used include titanium oxide, zinc oxide, zinc sulfide, white lead, calcium carbonate, precipitated barium sulfate, white carbon, alumina white, kaolin clay, talc, bentonite, black iron oxide, cadmium red, red oxide, molybdenum red, molybdate orange, chrome vermilion, yellow lead, cadmium yellow, yellow iron oxide, titanium yellow, chromium oxide, viridian, titanium cobalt green, cobalt green, cobalt chrome green, Victoria green, ultramarine, Prussian blue, cobalt blue, cerulean blue, cobalt silica blue, cobalt zinc silica blue, manganese violet, and cobalt violet.

[0020] Examples of organic pigments that can be used include azo pigments, phthalocyanine pigments, anthraquinone pigments, quinacridone pigments, isoindolinone pigments, quinophthalone pigments, dye lake pigments, and fluorescent pigments.

[0021] Specific organic pigments that can be used as magenta or red pigments include, for example, CI Pigment Red 2, CI Pigment Red 3, CI Pigment Red 5, CI Pigment Red 6, CI Pigment Red 7, CI Pigment Red 15, CI Pigment Red 16, CI Pigment Red 48:1, CI Pigment Red 53:1, CI Pigment Red 57:1, CI Pigment Red 122, CI Pigment Red 123, CI Pigment Red 139, CI Pigment Red 144, CI Pigment Red 149, CI Pigment Red 166, CI Pigment Red 177, CI Pigment Red 178, CI Pigment Red 222, CI Pigment Violet 19, CI Pigment Violet 29, and CI Pigment Violet 23.

[0022] Examples of pigments that can be used for orange or yellow include CI Pigment Orange 31, CI Pigment Orange 43, CI Pigment Yellow 12, CI Pigment Yellow 13, CI Pigment Yellow 14, CI Pigment Yellow 15, CI Pigment Yellow 16, CI Pigment Yellow 17, CI Pigment Yellow 74, CI Pigment Yellow 93, CI Pigment Yellow 94, CI Pigment Yellow 109, CI Pigment Yellow 128, and CI Pigment Yellow 138.

[0023] As the pigment for green or cyan, for example, CI Pigment Blue 15, CI Pigment Blue 15:2, CI Pigment Blue 15:3, CI Pigment Blue 15:4, CI Pigment Blue 16, CI Pigment Blue 60, CI Pigment Green 7, etc. can be used.

[0024] As the black pigment, for example, carbon black produced by the furnace method or the channel method can be used. In addition to carbon black, for example, aniline black, lumogen black, azomethine azo black, etc. can be used as the black pigment. In addition, it is also possible to use a plurality of chromatic pigments such as cyan pigments, magenta pigments, yellow pigments, brown pigments, orange pigments, etc. to make a black pigment. As the dye, it is possible to use acid dyes, reactive dyes, disperse dyes, etc. As specific compounds, it is possible to use acid dyes, reactive dyes, etc.

[0025] Examples of acid dyes include CI Acid Yellow 2, 3, 7, 17, 19, 23, 25, 29, 38, 42, 49, 59, 61, 72, and 99, CI Acid Orange 56 and 64, and CI Acid Red 1, 8, 14, 18, 26, 32, 37, 42, 52, 57, 72, 74, 80, 87, 115, 119, 131, 133, 134, 143, 154, 186, 249, 254, and 25 6, CI Acid Violet 11, 34, 75, CI Acid Blue 1, 7, 9, 29, 87, 126, 138, 171, 175, 183, 234, 236, 249, CI Acid Green 9, 12, 19, 27, 41, CI Acid Black 1, 2, 7, 24, 26, 48, 52, 58, 60, 94, 107, 109, 110, 119, 131, 155 can be used.

[0026] Examples of reactive dyes include CI Reactive Yellow 1, 2, 3, 13, 14, 15, 17, 37, 42, 76, 95, 168, and 175, CI Reactive Red 2, 6, 11, 21, 22, 23, 24, 33, 45, 111, 112, 114, 180, 218, 226, 228, and 235, and CI Reactive Blue 7, 14, 15, 18, 19, 21, 25, and 3 8, 49, 72, 77, 176, 203, 220, 230, 235, CI Reactive Orange 5, 12, 13, 35, 95, CI Reactive Brown 7, 11, 33, 37, 46, CI Reactive Green 8, 19, CI Reactive Violet 2, 4, 6, 8, 21, 22, 25, CI Reactive Black 5, 8, 31, 39 can be used.

[0027] As the disperse dye, various disperse dyes such as azo disperse dyes, quinone disperse dyes, anthraquinone disperse dyes, quinophthalone disperse dyes, etc. can be used. Specific compounds include, for example, CI Disperse Yellow 3, 4, 5, 7, 9, 13, 23, 24, 30, 33, 34, 42, 44, 49, 50, 51, 54, 56, 58, 60, 63, 64, 66, 68, 71, 74, 76, 79, 82, 83, 85, 86, 88, 90, 91, 93, 98, 99, 100, 104, 108, 114, 116, 118, 1 19,122,124,126,135,140,141,149,160,162,163,164,165,179,180,182,183,184 ,186,192,198,199,202,204,210,211,215,216,218,224,227,231,232,CIDisperse Orange1,3,5,7,11,13,17,20,21,25,29,30,31,32,33,37,38,42,43,44,45,46,47,48,49,50,53,54 ,55,56,57,58,59,61,66,71,73,76,78,80,89,90,91,93,96,97,119,127,130,139,142,CIDisperse Red1,4,5,7,11,12,13,15,17,27,43,44,50,52,53,54,55,56,58,59,60,65,72,73,74,7 5,76,78,81,82,86,88,90,91,92,93,96,103,105,106,107,108,110,111,113,117,118,121,122,126,127,128,131,132,134,135,137,143,145,146,151,152,153,154,157,159,164,167,169,177,179 ,181,183,184,185,188,189,190,191,192,200,201,202,203,205,206,207,210,221,224,225,227, 229,239,240,257,258,277,278,279,281,288,298,302,303,310,311,312,320,324,328,CIDisperse Violet1,4,8,23,26,27,28,31,33,35,36,38,40,43,46,48,50,51,52,56,57,59,61,63,69,77, CIDisperse Green9, CIDisperse Brown1,2,4,9,13,19, CIDisperse Blue3,7,9,14,16,19,20,26,27,35,43,44,54,55,56,58,60,62,64,71,72,73,75,79,81,82,83,87,91, 93,94,95,96,102,106,108,112,113,115,118,120,122,125,128,130,139,141,142,143,146,148,149,1 53, 154, 158, 165, 167, 171, 173, 174, 176, 181, 183, 185, 186, 187, 189, 197, 198, 200, 201, 205, 207, 211, 214, 224, 225, 257, 259, 267, 268, 270, 284, 285, 287, 288, 291, 293, 295, 297, 301, 315, 330, 333, CI Disperse Black 1, 3, 10, 24, etc. can be used.

[0028] (Method of manufacturing decorative sheet 10) The method for producing the decorative sheet 10 of this embodiment includes a base substrate forming step and a design layer forming step. Here, an example will be described in which the base material 1 is a sheet-shaped plastic base material (a base material made of resin).

[0029] <Base substrate forming process> The base substrate forming step is a step of forming the base substrate 1. In this embodiment, the surface 1a of the base substrate 1 on which the pattern layer 2 is formed is subjected to extrusion molding or other surface treatment, and the roughness of the surface is set so as to satisfy the condition of the following formula (1) in terms of arithmetic mean height Sa. 50μm≦Sa≦300μm (1) For example, the surface 1a of the base material 1 formed into a sheet shape was pressed to form a flat surface of 12 μm or less, and then an uneven shape satisfying the above formula (1) was imparted by embossing or the like.

[0030] <Pattern layer formation process> The design layer forming step is a step of forming the design layer 2. In the pattern layer forming process, an image is formed on the surface 1a of the base substrate 1 by inkjet printing using an ink containing a pigment and a dispersant as a colorant, or a dye as a colorant. Thus, the pattern layer 2 is formed. The colorant includes, for example, at least one of an organic pigment and an inorganic pigment. The inorganic pigment contained in the colorant includes, for example, at least one of cobalt blue, iron oxide, yellow iron oxide, and carbon black.

[0031] The organic pigment contained in the colorant includes, for example, at least one of CI Pigment Blue 15:3, CI Pigment Blue 15:4, CI Disperse Blue 60 (C), CI Pigment Red 122, CI Pigment Violet 19, CI Disperse Red 302 (M), CI Pigment Yellow 74, CI Pigment Yellow 16, CI Pigment Yellow 128, CI Pigment Yellow 109, CI Pigment Yellow 138, CI Disperse Yellow 149 (Y), and carbon black (K).

[0032] The above-described embodiment is one example of the present invention, and the present invention is not limited to the above-described embodiment. Various modifications can be made depending on the design, etc., even if the embodiment is a form other than the above-described embodiment, as long as the modifications do not deviate from the technical idea of ​​the present invention.

[0033] (effect) In the decorative sheet 10 of this embodiment, it is possible to improve the design by providing unevenness to the pattern forming surface 1a, while providing a stable pattern layer 2. As a result, it is possible to improve the design of the decorative sheet 10 in a more stable manner.

[0034] In the case of normal inkjet printing, the surface 1a of the base substrate 1 is often flat, as shown in Fig. 4(a). In this case, the ink 21 ejected from the inkjet head of the printer 20 lands regularly on the flat surface to form the pattern layer 2. However, because the surface on which the pattern is formed is flat, the design of the decorative sheet 10 is accordingly inferior.

[0035] On the other hand, as shown in Fig. 4(b), if the surface 1a of the base material 1 has significant surface irregularities, the regularly landing ink 21 will be buried in the surface irregularities, making the pattern unstable. In other words, even if a design is imparted to the pattern-forming surface, if there are more than a certain amount of irregularities, the pattern will not be stable and the desired pattern may not be formed.

[0036] In contrast to this, in the present embodiment, by defining the unevenness of the substrate surface 1a as described above, it is possible to impart design to the pattern-forming surface, as shown in Figure 4(c), while preventing the regularly lands of the ink 21 from being buried in the unevenness of the substrate, thereby ensuring stable formation of the pattern and enabling the desired pattern to be formed with high precision (see examples).

[0037] (Modification) (1) In the above embodiment, the decorative sheet 10 is configured to include a base substrate 1 and a pattern layer 2, but is not limited to this. The decorative sheet 10 may be configured to include a top coat layer 4 in addition to the base substrate 1 and the pattern layer 2, as shown in FIG. 2, for example. The top coat layer 4 is laminated on the design layer 2 and faces the surface of the base substrate 1 with the design layer 2 sandwiched therebetween. The topcoat layer 4 is a layer that is provided as necessary to impart design properties such as gloss, and surface properties such as scratch resistance and weather resistance. The topcoat layer 4 can be cured using known methods such as one-liquid, two-liquid, and active energy ray irradiation. The resin material used for the topcoat layer 4 can be known materials such as urethane-based, acrylic-based, and polyester-based materials.

[0038] (2) In the above embodiment, the decorative sheet 10 is configured to include the base substrate 1 and the pattern layer 2, but is not limited to this. That is, the decorative sheet 10 may be configured to include, in addition to the base substrate 1 and the pattern layer 2, a top coat layer 4 and a functional layer 6, for example, as shown in FIG. The functional layer 6 is formed on the surface (back surface) opposite the surface to be printed of the base substrate 1 (the upper surface in FIG. 3), for example, as an adhesive layer or the like whose surface is protected by a release sheet or the like.

[0039] In addition, for example, a woven fabric or nonwoven fabric may be laminated on the back surface of the base substrate 1. Furthermore, for example, a primer layer may be formed between the base substrate 1 and the design layer 2 in order to improve ink adhesion.

[0040] (others) The present disclosure may also have the following configuration. (1) A decorative sheet comprising a first layer and a pattern layer formed on the surface of the first layer by an inkjet printing method, The arithmetic mean height Sa of the surface roughness of the surface on which the pattern layer is formed in the first layer is in the range of 50 μm to 300 μm; A decorative sheet characterized by: (2) The first layer is made of a resin base material. (3) A method for producing a decorative sheet having a first layer and a pattern layer formed on a surface of the first layer, comprising: The arithmetic mean height Sa of the surface roughness of the first layer on which the pattern layer is formed is set to 50 μm or more and 300 μm or less, forming the pattern layer on the surface of the first layer by an inkjet printing method; A method for producing a decorative sheet comprising the steps of: EXAMPLES

[0041] Next, an example of this embodiment will be described. In this example, inkjet decoration was performed on base materials 1 with different surface irregularities, and it was confirmed whether the design of the pattern layer 2 was stably formed. Regarding the design, natural stone was used as a sample, and decoration was performed by inkjet printing with the goal of reproducing the unevenness and pattern of natural stone.

[0042] In each of the following examples, the layer structure of the decorative sheet 10 employed was such that a design layer 2 was formed on a base substrate 1 by inkjet printing, as shown in FIG.

[0043] <Example 1> Base material 1 is a material whose main component is aggregate with the addition of acrylic resin emulsion. In Example 1, the arithmetic mean height Sa of the upper surface was 152 μm. That is, a base substrate 1 having a certain degree of unevenness on the surface was adopted. In this Example 1, the substrate was sprayed with resin, dried, and then used. An embossed plate or the like was not pressed against the substrate, but the resin was naturally blended into the substrate, resulting in the substrate having an unevenness.

[0044] ·Pattern layer 2 The design layer 2 was formed on the surface of the base substrate 1 by a multi-pass inkjet printing method using UV ink. In this way, the decorative sheet 10 of Example 1 was produced. The UV ink used was TIC-JET 2012C-ST manufactured by Tokyo Ink Co., Ltd. The printed pattern was a dark stone pattern.

[0045] <Example 2> In Example 2, the arithmetic mean height Sa of the upper surface was adjusted to 200 μm. That is, a base substrate 1 having a surface with some degree of unevenness was used. The printed pattern formed was a light-colored stone pattern. The other conditions were the same as those in Example 1.

[0046] <Comparative Example 1> In Comparative Example 1, the arithmetic mean height Sa of the upper surface was adjusted to 12 μm, that is, a base substrate 1 having a flat surface was used. The printed pattern formed was a dark stone pattern. The other conditions were the same as those in Example 1.

[0047] <Comparative Example 2> In Comparative Example 2, the arithmetic mean height Sa of the upper surface was adjusted to 9 μm, that is, a base substrate 1 having a flat surface was used. The printed pattern formed was a light-colored stone pattern. The other conditions were the same as those in Example 1.

[0048] <Comparative Example 3> In Comparative Example 3, the arithmetic mean height Sa of the upper surface was adjusted to 325 μm. That is, a base substrate 1 having a large uneven surface was used. The printed pattern formed was a dark stone pattern. The other conditions were the same as those in Example 1.

[0049] <Comparative Example 4> In Comparative Example 4, the arithmetic mean height Sa of the upper surface was adjusted to 534 μm. That is, a base substrate 1 having a large uneven surface was used. The printed pattern formed was a light-colored stone pattern. The other conditions were the same as those in Example 1.

[0050] (evaluation) The evaluation results for each sample are shown in Table 1. [Table 1]

[0051] (Evaluation method) The evaluation methods shown in Table 1 are as follows. <Uneven feeling> The unevenness of the surface of the base material 1 was evaluated visually by applying light at an angle of 45 degrees.

[0052] <Print stability> Print stability is evaluated by continuously printing multiple sheets for each example, and determining the average color difference ΔE for the first 10 sheets based on the print state of the first sheet. The average color difference ΔE was evaluated as follows: △: ΔE<2 ○: ΔE<1 ◎: ΔE<0.5

[0053] <Design> The design was evaluated visually and judged according to the following criteria. ×: No unevenness, and the natural stone is not expressed. 〇: There is little unevenness, but the design of natural stone is expressed to a minimum extent. ◎: The design has a rough texture and expresses the natural stone design.

[0054] <Arithmetic mean height Sa> The height difference between the concave and convex parts (measurement of waviness) was measured using a microscope to determine the arithmetic mean height Sa.

[0055] <Evaluation Results> As can be seen from the measurement results shown in Table 1, in each of the examples based on the present disclosure, both print stability and design properties were good. [Explanation of symbols]

[0056] 1 Base material 1a surface 2. Picture layer 10 Decorative Sheet 20 Printers 21 Ink

Claims

1. A decorative sheet comprising a first layer and a pattern layer formed on a surface of the first layer by an inkjet printing method, The arithmetic mean height Sa of the surface roughness of the first layer on which the pattern layer is formed is in the range of 50 μm or more and 300 μm or less; A decorative sheet characterized by:

2. The first layer is made of a resin base material.

2. The decorative sheet according to claim 1.

3. A method for producing a decorative sheet having a first layer and a pattern layer formed on a surface of the first layer, comprising the steps of: The arithmetic mean height Sa of the surface roughness of the first layer on which the pattern layer is formed is set to 50 μm or more and 300 μm or less, and then forming the design layer on the surface of the first layer by an inkjet printing method; A method for producing a decorative sheet comprising the steps of:

Images