JP4625563B2 - Shading paper container - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a light-shielding paper container, and more particularly to a paper container having light-shielding properties and gas barrier properties.
[0002]
[Prior art]
Conventionally, in a container made mainly of paper that is hermetically filled with food and drink (hereinafter simply referred to as a paper container), in order to prevent deterioration of the quality of the contents, aluminum foil or aluminum vapor deposition is laminated to provide gas barrier properties and light shielding properties. The held paper containers are well known as, for example, containers for filling sake or soft drinks. In recent years, the contents to be filled in cheap paper containers are diversified, and it is desirable that the containers can be heated in a microwave when they need to be heated when eating or drinking. There is a problem that can not be heated in the range. In addition, when there is an aluminum layer on the container wall, there are disadvantages that a metal detector cannot be used in the filling machine and that there are disadvantages in recycling and disposal incineration. As means for solving the problem, there has been proposed a paper container provided with a light shielding layer composed of a transparent gas barrier layer and a colored resin layer without using aluminum foil or aluminum vapor deposition (for example, JP-A-6-238834). .
[0003]
[Problems to be solved by the invention]
Due to the diversification and ease of food in recent years, not only beverages but also solid, kneadable, viscous foods, or snack foods are filled into wide-mouthed cup-shaped paper containers so that they can eat and drink directly from the containers. Many foods and drinks have been sold. For foods and drinks filled in cup-shaped paper containers that are easily deteriorated by light or air, the light-shielding and gas barrier properties of cup-shaped paper containers are required. Is exclusively a container of the type that dispenses the liquid content from a thin spout, such as the Gobeltop rectangular parallelepiped shape shown in the above publication, and is a cup-shaped paper container that has both a gas barrier layer and a light shielding layer Have not yet been provided. Therefore, except for cup-shaped containers laminated or vapor-deposited with aluminum foil, filling of foods that require long-term storage in cup-shaped paper containers is not generally applied.
[0004]
In order to obtain a cup-shaped paper container having gas barrier properties and light-shielding properties, it is conceivable to apply the above-mentioned conventional technique. However, when a light-shielding layer made of a colored resin layer is provided, the colored resin is black to enhance the light-shielding properties. Since it is necessary to adopt a black system such as brown or brown, the inner surface of the cup becomes dark when applied to a cup-shaped container. Therefore, in a wide-mouthed container such as a paper cup-shaped container in which the contents are directly observed when eating the contents, there is a problem that the entire contents look dull and the appearance is deteriorated. In addition, when manufacturing a paper cup-shaped container, the body and the bottom are fixed with a thin film layer so that the adhesive flange portion and the body folded portion of the bottom wall are heated and rubbed with a pressure roller while being rubbed. The gas barrier layer that has been swelled is undulated, causing cuts and pinholes, resulting in a problem that gas barrier properties deteriorate. This is a problem that occurs not only in the case of a cup-shaped container but also in the case of a paper container of another shape to be thermoformed.
[0005]
The present invention was devised in view of the above circumstances, and in a paper container, particularly a wide-mouthed paper container such as a cup, can provide light shielding properties and gas barrier properties without providing an aluminum layer or aluminum deposition, Moreover, it is an object of the present invention to provide a paper container that can achieve light shielding without impairing the appearance of the contents, and can obtain excellent gas barrier properties by preventing pinholes and damage from occurring in the gas barrier layer. And
[0006]
[Means for Solving the Problems]
The light-shielding paper container of the present invention that solves the above problems is a wide-mouthed paper container in which the container wall is composed of a base material composed of a composite layer of a paper layer and a synthetic resin layer. It comprises a paper layer / thermoplastic resin layer / gas barrier layer / light-shielding layer / white colored resin layer / thermoplastic resin layer , and the white colored resin layer is composed of a white colored biaxially stretched PET film. It is what. The light-shielding paper container to which the present invention is applied can be applied to a paper container that is filled with contents that are altered or deteriorated by air or light. Suitable for wide-mouthed paper containers.
[0007]
The gas barrier layer is preferably composed of any one of an ethylene vinyl alcohol copolymer, an inorganic oxide vapor deposition film, and nylon, and the light shielding layer is composed of any one of black printing, gray printing, and a black resin film. Is desirable. The white colored resin layer is preferably composed of any one of a white colored thermoplastic resin such as a white colored olefin resin and a biaxially stretched film.
[0008]
The base material is composed of a thermoplastic resin layer / paper layer / thermoplastic resin layer / gas barrier layer / light shielding layer / white colored resin layer / thermoplastic resin layer from the outer surface, or no thermoplastic resin layer on the outer surface is provided. Thus, the outer surface layer may be composed of a paper layer. As the thermoplastic resin layer, polyethylene can be suitably employed.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
FIG. 1 shows a cup-shaped light-shielding paper container 1 according to an embodiment of the present invention. In the figure, 2 is a body part, 3 is a bottom part, and the body part 2 is affixed to both ends of a fan-shaped body blank. The bottom portion 3 is formed by bonding the circumferential portion of a disc-shaped bottom blank downwardly as shown in the figure to form a bonding flange 5. Then, the bonding flange 5 is squeezed by a body part bonding bent part 6 formed by bending the lower end part of the body part 2 inward, and is adhered by thermocompression bonding in that state. The trunk and the bottom are integrated. The trunk blank and the bottom blank are formed by punching from a base material 10 mainly composed of paper to be described later. In addition, 7 is a lid | cover material sticking part formed by carrying out the smooth process after curl shaping | molding of the trunk | drum upper part. The above structure is the same as that of a conventional cup-shaped paper container.
[0010]
FIG. 2 is an enlarged schematic view showing the layer structure of the base material constituting the container wall. The base material 10 constituting the light-shielding paper container of the present embodiment has a thermoplastic resin layer 11 / paper layer 12 / thermoplastic resin layer 13 / gas barrier layer 14 / light-shielding layer 15 / white colored resin layer 16 / heat from the outer surface. It is composed of a plastic resin layer 17. The thermoplastic resin layers 11 and 13 employ polyethylene in the present embodiment, but are not limited to polyethylene, and other polyolefin resins may be employed.
[0011]
Further, the gas barrier layer 14 may be composed of any of an ethylene vinyl alcohol copolymer, an inorganic oxide vapor deposition film such as an alumina vapor deposition polyethylene terephthalate film, and nylon, and in this embodiment, a 12 μm thick alumina vapor deposition polyethylene terephthalate. Adopted film. The light shielding layer 15 may be formed by printing using a light shielding ink such as a black ink or a gray ink, and may be formed by laminating a black resin film such as a black colored inflation film, for example. . Further, the white colored resin layer 16 may be made of polyethylene or biaxially stretched film. In the present embodiment, a black colored inflation film having a thickness of 40 μm is employed.
[0012]
When the light-shielding paper container is opened, the white-colored resin layer 16 prevents light from the inside of the container from being reflected by the light-shielding layer and the inner surface of the container from being darkened, thereby preventing the appearance of the contents from being deteriorated. This is provided mainly for this purpose, and is formed by mixing a white pigment with polyethylene or a biaxially stretched film. Therefore, the white colored resin layer 16 needs to be mixed with a white pigment in the resin so that the light shielding layer cannot be seen from the inner surface of the container. However, when the light shielding layer 5 is gray, the white colored resin layer 16 is mixed with polyethylene or a biaxially stretched film. There is an advantage that the pigment can be reduced. In addition to the above functions, the white colored resin layer 16 together with the thermoplastic resin layer 13 between the paper layer 12 and the gas barrier layer 14 reduces damage to the gas barrier layer 14 during thermocompression bonding during container molding. It has a function as a cushioning material. This prevents the gas barrier material from being cut or pinholes from being generated, and has the effect of enhancing the gas barrier properties. In that case, when a biaxially stretched PET film is used for the white colored resin layer 16 in particular, a high protective effect of the gas barrier material can be obtained.
[0013]
The cup-shaped light-shielding paper container of the present embodiment is configured as described above and has gas barrier properties and light-shielding properties. Therefore, even a wide-mouthed container is filled with contents that are easily altered by air or light. Can be distributed. In particular, the base material constituting the light-shielding paper container of this embodiment is provided with the white colored resin layer 16 inside the light-shielding layer, so that the light-shielding layer is formed of a black ink printing layer or a black resin film. Even if the inner peripheral surface of the container is not blackened, and the white colored resin layer is pure white, the contents are affected by the light shielding layer when opening the light shielding paper container and viewing the contents. On the contrary, the white colored resin layer does not darken the appearance, and a light-shielding paper container having a very high commercial value is obtained.
[0014]
Further, since the polyethylene layer 13 between the paper layer 12 and the gas barrier layer 14 is provided and the white colored resin layer 6 is provided inside the gas barrier layer 14 and the light shielding layer 15, the polyethylene layer 13 and the white colored resin are provided. The layer 16 functions as a cushioning material that reduces damage to the gas barrier layer 14 due to thermocompression bonding during container molding, and since it is a thin film, it can effectively protect a barrier material that is prone to breakage and pinholes. And a high gas barrier effect can be obtained.
[0015]
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various design change is possible within the range of the technical idea. For example, in the layer structure of the base material of the light-shielding paper container, the outermost thermoplastic resin layer 1 may not be provided and the paper layer may be the outermost layer. Further, the shape of the cup-shaped container is not limited to the circular shape (a) as shown in FIGS. 3A to 3D, for example, and the triangular shape (b), the quadrangular shape (c), Various cross-sectional shapes such as a polygonal shape such as a hexagonal shape (d) and an elliptical shape can be adopted. In the case of a cup-shaped container having these cross-sectional shapes, for example, the lower part of the body part connected to the bottom part may be formed into a circular shape in the same manner as a normal cup, and the upper part thereof may be formed in the various shapes described above. In addition, the light-shielding paper container of the present invention is not limited to a wide-mouthed container such as a cup-shaped container, but can be applied to any paper-made container of a gobeltop rectangular parallelepiped shape and a dispensing type. In this case, various shapes as shown in FIG.
[0016]
【The invention's effect】
As described above, according to the present invention, a light-shielding paper container having both light-shielding properties and gas barrier properties can be obtained without adopting aluminum foil or aluminum vapor deposition. There is no various inconvenience, and it is possible to obtain an inexpensive paper container that can be filled with contents that are easily altered by air or light and can be distributed. In particular, since a white colored resin layer is provided inside the light shielding layer, the inner surface of the container does not appear darkened even if it is used in a wide-mouthed paper container, and the appearance of the contents does not deteriorate. A light-shielding paper container with extremely high commercial value is obtained.
[0017]
In addition, the white colored resin layer functions as a cushioning material that reduces damage to the gas barrier layer during thermocompression bonding during container molding, effectively protecting barrier materials that are prone to breakage and pinholes. And a high gas barrier effect can be obtained.
[Brief description of the drawings]
FIG. 1 is a front sectional view of a light-shielding paper container according to an embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view of a base material of a light-shielding paper container.
FIGS. 3A to 3D illustrate various cross-sectional shapes of a light-shielding paper container.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cup-shaped paper container 2 trunk | drum 3 bottom 10 base material 11, 13, 17 thermoplastic resin layer 12 paper layer 14 gas barrier layer 15 light shielding layer 16 white colored resin layer

Claims (5)

In a wide-mouthed paper container in which the container wall is composed of a base material composed of a composite layer of a paper layer and a synthetic resin layer, the base material is a paper layer / thermoplastic resin layer / gas barrier layer / light shielding layer / white from the outer surface. A light-shielding paper container comprising a colored resin layer / thermoplastic resin layer, wherein the white colored resin layer is composed of a white-colored biaxially stretched PET film .   The light-shielding paper container according to claim 1, wherein the base material further includes a thermoplastic resin layer on an outer surface side of the paper layer.   The light-shielding paper container according to claim 1 or 2, wherein the gas barrier layer is composed of any one of an ethylene vinyl alcohol copolymer, an inorganic oxide vapor deposition film, and nylon.   The light-shielding paper container according to any one of claims 1 to 3, wherein the light-shielding layer is composed of any one of black printing, gray printing, and a black resin film.   The light-shielding paper container according to claim 1, wherein the light-shielding paper container is a cup-shaped paper container.

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