Search

JP-7856208-B1 - Method for manufacturing decorative sheets, decorative sheets, decorative materials, and resin compositions

JP7856208B1JP 7856208 B1JP7856208 B1JP 7856208B1JP-7856208-B1

Abstract

[Problem] To provide a method for manufacturing decorative sheets that can reduce the environmental burden when forming a surface protective layer and produce decorative sheets with good visibility. [Solution] A method for manufacturing a decorative sheet, comprising a surface protective layer formation step, a coating process of applying a resin composition to a substrate to form a coating layer, a first irradiation process of irradiating the coating layer with first wavelength light of 100 nm to less than 200 nm, and a second irradiation process of irradiating with second wavelength light or an electron beam of 200 nm to 450 nm to obtain a surface protective layer, wherein the resin composition contains an ionizing radiation-curable compound and particles containing a bifunctional or more modified (meth)acrylate monomer to which a modified species is added at a rate of 3 moles or more per mole of molecule, the viscosity at 25°C is 500 mPa·s or less, and the maximum value I max / minimum value I min of the reflectance intensity at a reflection angle of 30° to 60° when light is incident at an incident angle of 45° on the surface of the surface protective layer opposite to the substrate is 1.0 or more and 1.8 or less. [Selection Diagram] Figure 1

Inventors

  • 西垣 亮介
  • 桜井 玲子
  • 小紫 真友子

Assignees

  • 大日本印刷株式会社

Dates

Publication Date
20260511
Application Date
20251215

Claims (17)

  1. A substrate preparation step of preparing a substrate having a first surface and a second surface facing the first surface, A method for manufacturing a decorative sheet, comprising a surface protection layer forming step of forming a surface protection layer on the first surface of the substrate, The aforementioned surface protective layer formation step is, A coating process is performed to apply a resin composition to the first surface of the substrate to form a coating layer. A first irradiation treatment is performed in which the coated layer is irradiated with a first wavelength light of 100 nm or more and less than 200 nm to form a wrinkle structure on the surface opposite to the substrate, The invention comprises a second irradiation treatment in which the coated layer after the first irradiation treatment is irradiated with a second wavelength light or electron beam of 200 nm to 450 nm to obtain the surface protective layer, The resin composition comprises an ionizing radiation-curable compound containing a hexafunctional modified (meth)acrylate monomer to which a modified species is added at a rate of 3 moles or more per mole of molecule, and particles, and has a viscosity of 500 mPa·s or less at 25°C. The solvent content in the resin composition is 0% by mass or more and 10% by mass or less relative to the total mass of the resin composition. When light is incident on the surface of the surface protective layer opposite to the substrate at an incident angle of 45°, the ratio Imax / Imin of the maximum and minimum reflection intensity at reflection angles of 30 ° to 60 ° is 1.0 or more and 1.8 or less. The method for manufacturing a decorative sheet, wherein the surface protective layer formation step is performed after the second irradiation treatment, and includes an embossing treatment.
  2. A substrate preparation step of preparing a substrate having a first surface and a second surface facing the first surface, A method for manufacturing a decorative sheet, comprising a surface protection layer forming step of forming a surface protection layer on the first surface of the substrate, The aforementioned surface protective layer formation step is, A coating process is performed to apply a resin composition to the first surface of the substrate to form a coating layer. A first irradiation treatment is performed in which the coated layer is irradiated with a first wavelength light of 100 nm or more and less than 200 nm to form a wrinkle structure on the surface opposite to the substrate, The invention comprises a second irradiation treatment in which the coated layer after the first irradiation treatment is irradiated with a second wavelength light or electron beam of 200 nm to 450 nm to obtain the surface protective layer, The resin composition comprises an ionizing radiation-curable compound containing a hexafunctional modified (meth)acrylate monomer to which a modified species is added at a rate of 3 moles or more per mole of molecule, and particles, and has a viscosity of 500 mPa·s or less at 25°C. The solvent content in the resin composition is 0% by mass or more and 10% by mass or less relative to the total mass of the resin composition. The content of the modified (meth)acrylate monomer in the resin composition is 50% by mass or more relative to the mass of the ionizing radiation-curable compound in the resin composition. A method for manufacturing a decorative sheet, wherein when light is incident at an incident angle of 45° on the surface of the surface protective layer opposite to the substrate, the ratio Imax / Imin of the maximum value Imax to the minimum value Imin of the reflectance intensity at a reflection angle of 30° to 60° is 1.0 to 1.8.
  3. A substrate preparation step of preparing a substrate having a first surface and a second surface facing the first surface, A method for manufacturing a decorative sheet, comprising a surface protection layer forming step of forming a surface protection layer on the first surface of the substrate, The aforementioned surface protective layer formation step is, A coating process is performed to apply a resin composition to the first surface of the substrate to form a coating layer. A first irradiation treatment is performed in which the coated layer is irradiated with a first wavelength light of 100 nm or more and less than 200 nm to form a wrinkle structure on the surface opposite to the substrate, The invention comprises a second irradiation treatment in which the coated layer after the first irradiation treatment is irradiated with a second wavelength light or electron beam of 200 nm to 450 nm to obtain the surface protective layer, The resin composition comprises an ionizing radiation-curable compound containing a hexafunctional modified (meth)acrylate monomer to which a modified species is added at a rate of 3 moles or more per mole of molecule, and particles, and has a viscosity of 500 mPa·s or less at 25°C. The solvent content in the resin composition is 0% by mass or more and 10% by mass or less relative to the total mass of the resin composition. The aforementioned resin composition does not contain polymerizable polymers and polymerizable oligomers. A method for manufacturing a decorative sheet, wherein when light is incident at an incident angle of 45° on the surface of the surface protective layer opposite to the substrate, the ratio Imax / Imin of the maximum value Imax to the minimum value Imin of the reflectance intensity at a reflection angle of 30° to 60° is 1.0 to 1.8.
  4. The method for manufacturing a decorative sheet according to any one of claims 1 to 3, wherein the surface protective layer formation step includes a pre-curing treatment in which, after the coating treatment and before the first irradiation treatment, the coated layer is irradiated with light of a wavelength greater than 320 nm and less than or equal to 405 nm to pre-cure the resin composition.
  5. The method for manufacturing a decorative sheet according to claim 2 or 3, wherein the surface protective layer formation step includes an embossing process after the second irradiation treatment.
  6. A method for manufacturing a decorative sheet according to any one of claims 1 to 3, comprising a decorative layer formation step of forming a decorative layer on the first surface of the substrate after the substrate preparation step and before the surface protective layer formation step.
  7. A method for manufacturing a decorative sheet according to claim 6, comprising a transparent resin layer formation step, after the decorative layer formation step and before the surface protection layer formation step, in which a transparent resin layer is formed on the side of the decorative layer opposite to the substrate.
  8. The method for producing a decorative sheet according to any one of claims 1 to 3, wherein the modified species is at least one of ethylene oxide, propylene oxide, and ε-caprolactone.
  9. A method for manufacturing a decorative sheet according to any one of claims 1 to 3, wherein, in the coating process in the surface protective layer formation step, the resin composition is applied so as to cover 90% or more of the area of the first surface of the substrate.
  10. A method for manufacturing a decorative sheet according to any one of claims 1 to 3, wherein, in the first irradiation treatment, the temperature of the coated layer immediately before irradiation with the first wavelength light is 25°C or higher.
  11. A method for producing a decorative sheet according to claim 1 or 3, wherein the content of the modified (meth)acrylate monomer in the resin composition is 50% by mass or more relative to the mass of the ionizing radiation-curable compound in the resin composition.
  12. The method for producing a decorative sheet according to claim 1 or 2, wherein the resin composition does not contain polymerizable polymers and polymerizable oligomers.
  13. A method for producing a decorative sheet according to any one of claims 1 to 3, wherein the content of the particles in the resin composition is 0.1 parts by mass or more and 10.0 parts by mass or less per 100 parts by mass of the ionizing radiation-curable compound in the resin composition.
  14. A method for manufacturing a decorative sheet according to any one of claims 1 to 3, wherein the refractive index of the resin composition is 1.50 or less.
  15. The wrinkle structure has an uneven shape due to irregular wrinkles, The aforementioned irregular wrinkles have multiple protrusions formed by multiple projections and recesses formed by being surrounded by multiple projections. The method for manufacturing a decorative sheet according to any one of claims 1 to 3, wherein the projection has linear projections.
  16. A resin composition for forming the surface protective layer of a decorative sheet having a base material and a surface protective layer, An ionizing radiation-curable compound containing a hexafunctional modified (meth)acrylate monomer to which 3 moles or more of the modified species are attached per mole of molecule, and particles thereof, having a viscosity of 500 mPa·s or less at 25°C. The solvent content in the resin composition is 0% by mass or more and 10% by mass or less relative to the total mass of the resin composition. A resin composition in which the content of the modified (meth)acrylate monomer in the resin composition is 50% by mass or more relative to the mass of the ionizing radiation-curable compound in the resin composition.
  17. A resin composition for forming the surface protective layer of a decorative sheet having a base material and a surface protective layer, An ionizing radiation-curable compound containing a hexafunctional modified (meth)acrylate monomer to which 3 moles or more of the modified species are attached per mole of molecule, and particles thereof, having a viscosity of 500 mPa·s or less at 25°C. The solvent content in the resin composition is 0% by mass or more and 10% by mass or less relative to the total mass of the resin composition. The resin composition is a resin composition that does not contain polymerizable polymers and polymerizable oligomers.

Description

This disclosure relates to a method for manufacturing decorative sheets, decorative sheets, decorative materials, and resin compositions. For decorative sheets used in cosmetic materials, low gloss is sometimes required, for example, to improve aesthetic appeal. A method has been proposed for manufacturing a decorative sheet having a base material and a surface protective layer, wherein a surface protective layer is formed on the surface opposite the base material to obtain a decorative sheet exhibiting low gloss. For example, Patent Documents 1 and 2 disclose a decorative sheet including a base material layer and a surface protective layer, wherein the surface protective layer has low gloss. Patent No. 7243755Japanese Patent Publication No. 2022-25623 This is a schematic cross-sectional view illustrating the method for manufacturing the decorative sheet in this disclosure.This flowchart illustrates the surface protective layer formation process in this disclosure.These are the measurement results of the reflectance intensity when light is incident at an incident angle of 45° on the surface protective layer in this disclosure and on a conventional surface protective layer.This is an example of a microscopic image of the surface protective layer of the decorative sheet in this disclosure.This is a schematic cross-sectional view illustrating the method for manufacturing the decorative sheet in this disclosure.This is a schematic cross-sectional view illustrating a decorative sheet in this disclosure.This is a schematic cross-sectional view illustrating an example of a cosmetic material in this disclosure. The embodiments will be described below with reference to the drawings and other illustrations. However, this disclosure can be implemented in many different forms, and should not be limited to the embodiments described below. Furthermore, while the drawings may schematically represent the width, thickness, and shape of each part compared to the actual form in order to clarify the explanation, these are merely examples and should not be interpreted as limiting. In this specification, when describing a configuration in which one component is placed on top of another component, the terms "above" or "below" include, unless otherwise specified, both cases: the other component being placed directly above or below the component in contact with it, and the other component being placed above or below the component via yet another component. Furthermore, in this specification, when describing a configuration in which one component is placed on the surface of another component, the terms "on the surface" or "on the side of the surface" include, unless otherwise specified, both cases: the other component being placed directly above or below the component in contact with it, and the other component being placed above or below the component via yet another component. Furthermore, in this specification, the terms “board,” “sheet,” and “film” are not distinguished from each other solely based on differences in name. For example, “sheet” includes components that are also called “board” or “film.” The manufacturing method of the decorative sheet, the decorative sheet, the decorative material, and the resin composition described herein will be explained in detail below. A. Method for manufacturing a decorative sheet The method for manufacturing a decorative sheet according to this disclosure comprises a substrate preparation step of preparing a substrate having a first surface and a second surface facing the first surface, and a surface protection layer formation step of forming a surface protection layer on the first surface of the substrate, wherein the surface protection layer formation step comprises a coating process of applying a resin composition to the first surface of the substrate to form a coating layer, a first irradiation process of irradiating the coating layer with first wavelength light of 100 nm or more and less than 200 nm to form a wrinkle structure on the surface opposite to the substrate, and the above The present invention provides a second irradiation treatment to obtain the surface protective layer by irradiating the coated layer with a second wavelength light or electron beam of 200 nm to 450 nm, wherein the resin composition comprises an ionizing radiation-curable compound containing a bifunctional or more modified (meth)acrylate monomer to which a modified species is added at a rate of 3 moles or more per mole of molecule, and particles, the viscosity at 25°C is 500 mPa· s or less, and the ratio Imax / Imin of the maximum and minimum reflection intensity at a reflection angle of 30° to 60° when light is incident at an incident angle of 45° on the surface of the surface protective layer opposite to the substrate is 1.0 to 1.8. Figure 1 is a schematic cross-sectional view illustrating a method for manufacturing a decorative sheet according to this disclosure. First, as shown in Figure 1(a), a substrat