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EP-4737119-A1 - MULTILAYER RESIN SHEET FOR MOLDING, AND MOLDED ARTICLE USING SAME

EP4737119A1EP 4737119 A1EP4737119 A1EP 4737119A1EP-4737119-A1

Abstract

According to the present invention, there can be provided a laminated resin sheet for molding, comprising: a high-hardness resin layer comprising a high-hardness resin, a base material layer comprising a polycarbonate resin (a1), disposed on one surface side of the high-hardness resin layer, and a hard coat layer, disposed on the other surface side of the high-hardness resin layer, wherein the hard coat layer has an indentation creep of 7.0% or less and a maximum indentation depth of 890 nm or less in an indentation test, the hard coat layer consists of a hard coating composition containing: (A) a 2 to 15 functional (meth)acrylate oligomer, (B) a 1 or 2 functional (meth)acrylate monomer having a molecular weight of less than 200, (C) a photopolymerization initiator, and (D) a surface modifier, and the content of the component (C) is 1.2 to 1.8 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D).

Inventors

  • TAKASAKI, MASATO
  • KAWABE, Kiyoto
  • KOKUBU, Hiroko
  • SUZUKI, YUTO

Assignees

  • MITSUBISHI GAS CHEMICAL COMPANY, INC.

Dates

Publication Date
20260506
Application Date
20240627

Claims (11)

  1. A laminated resin sheet for molding, comprising: a high-hardness resin layer comprising a high-hardness resin, a base material layer comprising a polycarbonate resin (a1), disposed on one surface side of the high-hardness resin layer, and a hard coat layer, disposed on the other surface side of the high-hardness resin layer, wherein the hard coat layer has an indentation creep of 7.0% or less and a maximum indentation depth of 890 nm or less in an indentation test, the hard coat layer consists of a hard coating composition comprising: (A) a 2 to 15 functional (meth)acrylate oligomer, (B) a 1 or 2 functional (meth)acrylate monomer having a molecular weight of less than 200, (C) a photopolymerization initiator, and (D) a surface modifier, and a content of the component (C) is 1.2 to 1.8 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D).
  2. The laminated resin sheet for molding according to claim 1, wherein the indentation creep is 5.3% to 7.0% and the maximum indentation depth is 700 to 890 nm in the indentation test.
  3. The laminated resin sheet for molding according to claim 1 or 2, wherein a content of the component (A) is 40 to 70 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D), a content of the component (B) is 20 to 55 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D), and a content of the component (D) is 0.1 to 10 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D).
  4. The laminated resin sheet for molding according to any one of claims 1 to 3, wherein the polycarbonate resin (a1) is an aromatic polycarbonate resin.
  5. The laminated resin sheet for molding according to any one of claims 1 to 4, wherein the aromatic polycarbonate resin comprises a constituent unit represented by the following formula (3a):
  6. The laminated resin sheet for molding according to any one of claims 1 to 5, wherein a content of the polycarbonate resin (a1) is 75% to 100% by mass, with respect to a total mass of the base material layer.
  7. The laminated resin sheet for molding according to any one of claims 1 to 6, wherein a content of the high-hardness resin is 70% to 100% by mass, with respect to a total mass of the high-hardness resin layer.
  8. The laminated resin sheet for molding according to any one of claims 1 to 7, wherein a total thickness of the base material layer and the high-hardness resin layer is 0.5 to 3.5 mm.
  9. The laminated resin sheet for molding according to any one of claims 1 to 8, wherein a percentage of a thickness of the base material layer in a total thickness of the base material layer and the high-hardness resin layer is 75% to 99%.
  10. The laminated resin sheet for molding according to any one of claims 1 to 9, wherein a pencil hardness on a surface of the hard coat layer is 2H or more
  11. A molded product molded using the laminated resin sheet for molding according to any one of claims 1 to 10.

Description

Technical Field The present invention relates to a laminated resin sheet for molding and a molded product using the same. Background Art Resin molded bodies are used in automotive interior parts such as instrument covers, housings for home appliances, office automation equipment, personal computers and small portable devices, and touch panel-type display surfaces for mobile phone terminals. Resin molded bodies used for such intended uses are produced by molding resin sheets for molding. Polycarbonate (PC) resin has been attracting attention as a resin suitable for the above-mentioned intended uses. PC resin is known as an engineering plastic (en-pla) that is excellent in terms of transparency, lightness and impact resistance, and is preferably applied to the above-mentioned intended uses. For example, Patent Literature 1 describes an invention relating to a polycarbonate resin laminate with a hard coat layer for hot bending, which is characterized in that it is formed by laminating a hard coat layer on at least one surface of a polycarbonate resin. Besides, the invention described in Patent Literature 1 provides a method for producing a curved member that is excellent in terms of abrasion resistance, hot bending property, and adhesion after hot bending. However, as in Patent Literature 1, since the outermost surface of a polycarbonate resin molded product does not have sufficient pencil hardness, the polycarbonate resin molded product is easily scratched by contact with hard materials. Thus, the polycarbonate resin molded product has been problematic in that it cannot be applied to the housings of small portable devices, which require high surface hardness, or for touch panel-type display surfaces of mobile phones, etc. Citation List Patent Literature Patent Literature 1: WO2021/070632 Summary of Invention Technical Problem Thus, it is an object of the present invention to provide: a laminated resin sheet for molding that has high hardness and scratch resistance, and also, is less likely to cause appearance abnormalities during molding and has excellent adhesion; and a molded product using the same. Solution to Problem The present inventors have conducted intensive studies directed towards achieving the above-described object, and as a result, the inventors have found that the above-described object can be achieved by establishing a high-hardness resin layer on a polycarbonate resin layer (base material layer) and further establishing a hard coat layer comprising a specific component on the high hardness-resin layer. Specifically, the present invention is as follows. < 1 > A laminated resin sheet for molding, comprising: a high-hardness resin layer comprising a high-hardness resin,a base material layer comprising a polycarbonate resin (a1), disposed on one surface side of the high-hardness resin layer, anda hard coat layer, disposed on the other surface side of the high-hardness resin layer, wherein maximum indentation depth of 890 nm or less in an indentation test,the hard coat layer consists of a hard coating composition containing: (A) a 2 to 15 functional (meth)acrylate oligomer,(B) a 1 or 2 functional (meth)acrylate monomer having a molecular weight of less than 200,(C) a photopolymerization initiator, and(D) a surface modifier, andthe content of the component (C) is 1.2 to 1.8 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D).< 2 > The laminated resin sheet for molding according to the above < 1 >, wherein the indentation creep is 5.3% to 7.0% and the maximum indentation depth is 700 to 890 nm in the indentation test.< 3 > The laminated resin sheet for molding according to the above < 1 > or < 2 >, wherein the content of the component (A) is 40 to 70 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D),the content of the component (B) is 20 to 55 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D), andthe content of the component (D) is 0.1 to 10 parts by mass, with respect to 100 parts by mass of a total of the component (A), the component (B), the component (C), and the component (D).< 4 > The laminated resin sheet for molding according to any one of the above < 1 > to < 3 >, wherein the polycarbonate resin (a1) is an aromatic polycarbonate resin.< 5 > The laminated resin sheet for molding according to any one of the above < 1 > to < 4 >, wherein the aromatic polycarbonate resin comprises a constituent unit represented by the following formula (3a): < 6 > The laminated resin sheet for molding according to any one of the above < 1 > to < 5 >, wherein the content of the polycarbonate resin (a1) is 75% to 100% by mass, with respect to the total mass of the base material layer.< 7 > The laminated resin sheet for molding according to any