JP-2026075465-A - Coated paper

Abstract

[Problem] To provide coated paper that can be recycled from a paper substrate. [Solution] A coated paper comprising a base material, a primer layer, and a coating layer in that order, wherein the base material mainly contains paper, and the primer layer mainly contains a specific resin consisting of at least one of a urethane resin and an acrylic resin. [Selection Diagram] Figure 1

Inventors

• 子安 亜祐里
• 林 拓也

Assignees

• 大阪シーリング印刷株式会社

Dates

Publication Date

20260508

Application Date

20241022

Claims (7)

1. The substrate, primer layer, and coating layer are arranged in this order. The aforementioned substrate mainly contains paper, The primer layer mainly comprises a specific resin consisting of at least one of a urethane resin and an acrylic resin. Coated paper.
2. The coated paper according to claim 1, wherein the coating layer is water-resistant.
3. The coated paper according to claim 2, wherein the coating layer is a heat-seal layer.
4. The coated paper according to claim 1 or 2, wherein the primer layer is insoluble in water.
5. The coated paper according to claim 1 or 2, wherein the urethane-based resin is a hydroxypolyurethane resin.
6. The acrylic resin is a coated paper according to claim 1 or claim 2, wherein the acrylic resin has carboxyl groups.
7. The substrate has a first surface that is in contact with the primer layer, The coated paper according to claim 1 or claim 2, wherein the first surface is made of paper.

Description

This invention relates to coated paper. Patent Document 1 discloses a heat-sealable paper having a coating layer on at least one surface of a paper substrate. The coating layer provides heat-sealability. A sealing layer is provided between the paper substrate and the coating layer. The sealing layer prevents the coating liquid forming the coating layer from seeping into the paper substrate. Hereinafter, the sealing layer will be referred to as the primer layer. Japanese Patent Publication No. 2023-067887 Figure 1 is a schematic cross-sectional view showing the coated paper of the embodiment. Specific examples of the coated paper of the present invention will be described based on the drawings. The dimensions of the components shown in the drawings are for illustrative purposes only and do not necessarily represent actual dimensions and proportions. Furthermore, the present invention is not limited to these examples, but is defined by the claims, and all modifications within the meaning and scope equivalent to the claims are intended. [Embodiment] <Coated paper> As shown in Figure 1, coated paper 1 comprises a base material 2, a primer layer 3, and a coating layer 4 in this order. This arrangement means that the base material 2, primer layer 3, and coating layer 4 are laminated in sequence, with no other layers positioned between the base material 2 and the primer layer 3, or between the primer layer 3 and the coating layer 4. One of the features of coated paper 1 is that the base material 2 contains paper as its main component, and the primer layer 3 contains a specific resin, at least one of a urethane-based resin and an acrylic-based resin, as its main component. ≪Base material≫ The base material 2 contains paper as its main component. "Containing paper as its main component" means that the paper content in the base material 2 exceeds 50% by mass. The paper may be pulp, or it may contain other dietary fibers. The paper content in the base material 2 may be 80% by mass or more, 95% by mass or more, 98% by mass or more, or 100% by mass. A paper content of 100% by mass in the base material 2 means that the base material 2 is substantially composed solely of paper. "Substantially composed solely of paper" means that, excluding impurities, it intentionally does not contain any components other than paper. A base material 2 substantially composed solely of paper is environmentally friendly. The paper content in the base material 2 is the percentage of the total mass of the constituent materials of the base material 2, which is 100% by mass. The paper may also contain resin fibers. The resin fiber content in the base material 2 is less than 50% by mass. The type of paper is not particularly limited. Any publicly known paper can be used. Examples of such papers include fine paper, recycled paper, glossy paper, oil-resistant paper, coated paper, art paper, kraft paper, glassine paper, or Cascoat paper. The base material 2 is formed in a sheet shape. The base material 2 has a first surface 21 and a second surface 22. The first surface 21 and the second surface 22 are surfaces facing opposite directions in the direction along the thickness of the base material 2. The first surface 21 is the surface in contact with the primer layer 3. The first surface 21 is made of, for example, paper. When the first surface 21 is made of paper, a portion of the constituent material of the primer layer 3 interlocks with the fibers constituting the paper, creating an anchoring effect. This anchoring effect makes it easier for the primer layer 3 to adhere to the first surface 21 of the base material 2. The thickness of the base material 2 is not particularly limited and can be any known thickness. <Primer layer> The primer layer 3 functions as a sealing layer that prevents the material forming the coating layer 4 from seeping into the substrate 2. The primer layer 3 is provided on the first surface 21 of the substrate 2. This means that the primer layer 3 is in direct contact with the first surface 21. In other words, there are no other layers between the substrate 2 and the primer layer 3. The primer layer 3 covers the entire surface of the first surface 21. The primer layer 3 has a first surface 31 and a second surface 32. The first surface 31 and the second surface 32 are surfaces facing opposite directions in the direction along the thickness of the primer layer 3. The first surface 31 is the surface facing the opposite direction from the surface facing the substrate 2. The second surface 32 is the surface facing the substrate 2 and is in direct contact with the substrate 2. The primer layer 3 has a single-layer structure. The primer layer 3 contains a specific resin as its main component, consisting of at least one of a urethane-based resin and an acrylic-based resin. "Containing the specific resin as its main component" means that the content of the specific resin in the primer layer 3 is 90% by mass or more. The content of the