JP-7854776-B2 - Vapor deposition substrates, laminates, and packaging containers

Inventors

• 山田 憲一

Assignees

• 大日本印刷株式会社

Dates

Publication Date

20260507

Application Date

20200331

Claims (10)

1. A vapor deposition substrate comprising at least a substrate and a vapor-deposited film, The substrate comprises at least a polyethylene resin layer and a surface resin layer, The aforementioned substrate is a co-extruded film, The polyethylene resin layer is provided with a density gradient. The vapor-deposited film is provided on the surface resin layer of the substrate , A barrier coating layer is further provided on the aforementioned vapor-deposited film. The aforementioned surface resin layer contains a resin material having a melting point of 150°C or higher. The aforementioned substrate is characterized by having undergone a stretching treatment, wherein the substrate is a vapor-deposited substrate.
2. The surface resin layer comprises a resin material having a melting point of 150°C or higher and 265°C or lower, as described in claim 1.
3. The vapor deposition substrate according to claim 1 or 2, wherein the melting point difference between the polyethylene resin and the resin material of the surface resin layer having a melting point of 150°C or higher is 20 to 80°C.
4. The resin material of the surface resin layer is made of a polymer having polar groups, as described in any one of claims 1 to 3, for the vapor deposition substrate.
5. The vapor deposition substrate according to any one of claims 1 to 4, wherein the resin material of the surface resin layer is at least one resin material selected from the group consisting of ethylene vinyl alcohol copolymer, polyvinyl alcohol, polyester, nylon 6, nylon 6,6, nylon 6-nylon 6,6 copolymer, MXD nylon, and amorphous nylon.
6. The vapor-deposited substrate according to any one of claims 1 to 5, wherein the ratio of the thickness of the surface resin layer to the total thickness of the substrate is 2% or more and 20% or less.
7. The vapor-deposited substrate according to any one of claims 1 to 6, wherein the polyethylene resin layer of the substrate has a multilayer structure.
8. The vapor-deposited substrate according to claim 7, wherein the polyethylene resin layer of the substrate comprises at least one layer containing a compatibilizer.
9. The vapor deposition substrate according to claim 8, wherein the surface resin layer is provided in contact with the layer containing the compatibilizer for the polyethylene resin layer.
10. A vapor-deposited substrate according to any one of claims 1 to 9 , used in packaging containers.

Description

This invention relates to a vapor-deposited substrate, a laminate, and a packaging container. Conventionally, resin films made from polyester resins such as polyethylene terephthalate (hereinafter also referred to as polyester films) have been used in the manufacture of packaging containers because they have excellent mechanical properties, chemical stability, heat resistance, and transparency, as well as being inexpensive. Such polyester films are used as a base material and are typically laminated with a polyethylene film, which serves as a sealant layer, to form a laminate that is then molded into a packaging container. The packaging containers obtained by molding a vapor-deposited substrate, which is a laminate of different types of resin films—namely, polyester film and polyethylene film—are difficult to separate into their respective layers. Therefore, these used packaging containers are not suitable for recycling and are not actively recycled. In light of this situation, and with the aim of improving the recyclability of packaging containers, the production of packaging containers (monomaterial packaging containers) using stretched polyethylene film (stretched polyethylene film) as the base material instead of polyester film, and using a vapor-deposited base material made of the same material, is being considered. This is a schematic cross-sectional view showing one embodiment of the vapor-deposited substrate of the present invention.This is a schematic cross-sectional view showing one embodiment of the vapor-deposited substrate of the present invention.This is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus.This is a schematic cross-sectional view showing one embodiment of a vapor deposition apparatus.This is a schematic cross-sectional view showing one embodiment of the laminate of the present invention.This is a front view showing one embodiment of the packaging container of the present invention.This is a perspective view showing one embodiment of the packaging container of the present invention.This is a front view showing one embodiment of the packaging container of the present invention.This is a cross-sectional view taken along line a-a in Figure 8. (vapor deposition base material) As shown in Figure 1, the vapor-deposited substrate 10 of the present invention comprises a substrate 11 and a vapor-deposited film 12, the substrate 11 comprising a polyethylene resin layer 13 and a surface resin layer 14. A vapor-deposited substrate having such a configuration can be suitably used as a substrate for monomaterial packaging containers, and the adhesion between the layers and the vapor-deposited film is significantly improved, resulting in a vapor-deposited substrate with high gas barrier properties. The ratio of the thickness of the surface resin layer to the total thickness of the substrate is preferably 2% to 20%, and more preferably 4% to 15%. By setting the ratio of the surface resin layer thickness to the total thickness of the substrate to 2% or more, the adhesion of the vapor-deposited film can be further improved, and the gas barrier properties of the substrate on which the vapor-deposited film is formed can be further improved. Furthermore, by setting the ratio of the surface resin layer thickness to the total thickness of the base material to 20% or less, the base material can be made suitable for use in the manufacture of monomaterial packaging containers. In addition, the film-forming properties and processability of the base material can be further improved. Furthermore, in one embodiment, the base material 11 may further include an adhesive resin layer 15 between the polyethylene resin layer 13 and the surface resin layer 14, as shown in Figure 2. Furthermore, in one embodiment, the vapor-deposited substrate 10 of the present invention comprises a barrier coat layer on the vapor-deposited film 12 (not shown). The following describes each layer of the vapor-deposited substrate of the present invention. (Base material) In this invention, the substrate is characterized by being subjected to a stretching treatment. This improves the strength and heat resistance of the substrate. It also improves printability. The stretching process may be uniaxial stretching or biaxial stretching. The stretching ratio of the substrate in the longitudinal direction (MD direction) and transverse direction (TD direction) is preferably 2 times or more and 15 times or less, and preferably 5 times or more and 13 times or less. By increasing the stretching ratio to 2 times or more, the strength and heat resistance of the substrate can be further improved. Furthermore, the printability of the substrate can be improved. Furthermore, from the viewpoint of the breaking limit of the substrate, it is preferable that the stretch ratio is 15 times or less. In one embodiment, the substrate of the present invention is a co-extruded film. Furthermore, in one embodiment, the substrate