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JP-2026075788-A - packaging

JP2026075788AJP 2026075788 AJP2026075788 AJP 2026075788AJP-2026075788-A

Abstract

[Problem] To provide a packaging material that can be used as a container after heat treatment and can be easily deformed into the intended shape. [Solution] A heat-treated packaging body 1 having an expandable internal space 4 surrounded by a surface layer 2 and a back layer 3, wherein at least one of the surface layer 2 and the back layer 3 contains paper and/or pulp, and is configured to be usable as a container after heat treatment, comprising an annular seal portion 50 that can join the surface layer 2 and the back layer 3 in an annular shape in a plan view, and a partial seal portion 70 that partially joins the surface layer 2 and the back layer 3 on the inner side of the annular seal portion 50. [Selection Diagram] Figure 1

Inventors

  • 西 彩子
  • 下野 貴裕

Assignees

  • ＴＯＰＰＡＮホールディングス株式会社

Dates

Publication Date
20260511
Application Date
20241023

Claims (8)

  1. A heat-treated packaging body having an expandable internal space surrounded by a surface layer and a back layer, The surface layer and the back layer contain paper and/or pulp, and are configured to be usable as a container after heat treatment. An annular sealing portion that can join the surface layer and the back layer in an annular shape when viewed from above, A partial seal portion that partially joins the surface layer and the back layer on the inner side of the annular seal portion, A packaging body equipped with the following features.
  2. The packaging according to claim 1, wherein the partial sealing portion is formed to extend inward from the annular sealing portion while being connected to it.
  3. Let i be the shortest distance between the leading edge of the partial seal portion in the extending direction and the annular seal portion, and let L be the inner dimension of the annular seal portion in the extending direction of the partial seal portion. The packaging according to claim 2, wherein the ratio (i/L) × 100 of the shortest distance (i) to the inner dimension (L) is set to 3.0 to 23.0.
  4. The packaging according to claim 1, wherein the partial seal portion is formed separately from the annular seal portion.
  5. Let i be the shortest distance between the point on the outer contour of the partial seal portion closest to the center of the annular seal portion and the annular seal portion, and let L be the inner dimension of the annular seal portion in the direction of extension of the imaginary straight line connecting the point and the annular seal portion by the shortest distance (i), The packaging according to claim 4, wherein the ratio (i/L) × 100 of the shortest distance (i) to the inner dimension (L) is set to 3.0 to 23.0.
  6. A steam seal portion is provided so as to be able to form a pressure relief port to suppress an excessive pressure rise in the internal space. The packaging according to claim 1, wherein the partial sealing portion is positioned opposite the steam sealing portion with respect to the center of the annular sealing portion.
  7. The packaging according to claim 1, wherein the partial sealing portions are arranged opposite each other, with the center of the annular sealing portion in between.
  8. A packaging body according to any one of claims 1 to 7, used as a food container for heating food intended for microwave cooking.

Description

This invention relates to a heat-treated packaging material. For example, there are known flat-type pouches that contain food or other contents and are heated horizontally in a microwave oven (see, for example, Patent Document 1). Patent Document 1 discloses a plastic pouch formed by overlapping a plastic film constituting the surface of the pouch with a plastic film constituting the back surface of the pouch, and heat-sealing the periphery. In this plastic pouch, an opening is provided at a position away from the heat-sealed periphery, and a vapor-venting seal portion is formed surrounding the opening. When this plastic pouch is placed flat in a microwave oven and heated, the internal pressure of the pouch increases due to steam and other substances generated from the contents, causing the pouch to expand. As the pouch expands, the steam vent seal gradually peels away towards the opening. Once the peeling progresses to the opening, the steam and other substances are released to the outside, and the internal pressure of the pouch decreases. Japanese Patent Publication No. 2006-62672 Figure 1 is a perspective view showing a package according to one embodiment of the present invention.Figure 2 is an explanatory diagram of the laminated structure of the front and back sheets.Figure 3 is a diagram illustrating the structure of the packaging.Figure 4 is a simplified model diagram of the annular seal portion and the partial seal portion.Figure 5 is an explanatory diagram of the procedure when using the container as a food container for heating.Figure 6 is a perspective view showing the backing sheet being used as a container.Figure 7 is an explanatory diagram of another embodiment (1) of the heat seal portion.Figure 8 is an explanatory diagram of another embodiment (2) of the heat seal portion.Figure 9 is an explanatory diagram of another embodiment (3) of the heat seal portion. The present invention will be described below with reference to the drawings. In the following embodiments, a packaging body used as a food container for heating food (contents M) to be cooked in a microwave oven will be used as an example. However, the present invention is not intended to be limited to the embodiments, configurations, or examples described below. Note that in Figures 1-3, 5, and 6, the thicknesses of the surface layer 2 and the back layer 3, and the thickness relationships of the multiple layers 2a, 2b, 3a-3d constituting each layer 2 and 3, have been exaggerated or simplified as appropriate, and do not strictly reflect the actual relative thicknesses (scale) of each layer. <Schematic configuration> Figure 1 is a perspective view showing a package 1 according to one embodiment of the present invention. Figure 1(a) is a perspective view showing the state of the package 1 containing contents M before expansion, and Figure 1(b) is a perspective view showing the state of the package 1 containing contents M after expansion. The package 1 shown in Figures 1(a) and (b) comprises a front layer 2 and a back layer 3, and has an expandable internal space 4 surrounded by the front layer 2 and the back layer 3. At least one of the front layer 2 and the back layer 3 contains paper and/or pulp, which is a type of molding sheet and/or molding filler, and is configured to be usable as a container after heat treatment. In the following description, an embodiment in which paper and/or pulp is included in the back layer 3 will be given as an example. In this embodiment, both the front layer 2 and the back layer 3 are made of sheet material, and in the following, "front layer 2" will be referred to as "front sheet 2" and "back layer 3" as "back sheet 3". <Table Sheet> Figure 2 is an explanatory diagram of the laminated structure of the front sheet 2 and the back sheet 3. Figure 2(a) is a cross-sectional view showing the laminated structure of the front sheet 2. As shown in Figure 2(a), the front sheet 2 is a multilayer sheet in which a base layer 2a and a sealant layer 2b are laminated. The base layer 2a is located on the side that will be the outside of the packaging body 1. The sealant layer 2b is located facing the internal space 4 of the packaging body 1. The base layer 2a constituting the top sheet 2 is not particularly limited, as long as it is made of a heat-resistant resin film that can be used as food packaging material for heating and cooking in a microwave oven. Examples of resin types include polyethylene terephthalate (PET), nylon film (Ny), polypropylene (PP), polyvinylidene chloride (PVDC), polyvinyl chloride (PVC), polymethylpentene (PMP), and polyethylene (PE). The resin film may be stretched. Alternatively, the resin film may be a composite resin film formed by laminating two or more of these resins. The thickness of the base layer 2a is preferably 10 to 200 μm, and more preferably 20 to 150 μm. The sealant layer 2b constituting the front sheet 2 is not particularly limited as long as it is a heat-adhesive resin that does n