packaging

Abstract

To provide a package that can be resealed even after the package is opened, where the package enables heating in a microwave oven together with a container.SOLUTION: A package 1 comprises a container main body 2 and a lid material 3 sealing an opening part of the container main body, which can be heated in a microwave oven. The lid material has a U-shaped notch 4 serving as an extraction port for contents and a through-hole 7 formed at a portion separated from a U-shaped bottom part 5, where the lid material is attached with an adhesive sheet member 6 for resealing which covers the U-shaped notch and the whole of the through-hole. The adhesive sheet member is torn off upward from the bottom part of the U-shaped notch and then the package is resealed, so that the through-hole acts as a steam venting hole when the package is heated in the microwave oven.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a package that primarily contains food, has a resealable opening, and can be heated directly in a microwave oven. [Background technology]

[0002] Various packages have been proposed for storing food that can be heated in a microwave oven after being taken out of a refrigerator. The lid described in Patent Document 1 is a sealed lid that automatically releases steam when the container is heated in a microwave oven.

[0003] The lid material described in Patent Document 1 has a steam release hole and a steam release label that seals it. The steam release label has a non-adhesive area that covers the steam release hole, a weakly adhesive area that forms a steam passageway from the non-adhesive area to the end of the label, and a strong adhesive area adjacent to the outside of the non-adhesive area and the weakly adhesive area. The non-adhesive area is a strong adhesive layer that is applied to the entire surface of the steam release label and then a non-adhesive coating layer that is applied to the strong adhesive layer with a coating area ratio of 10% to 90%. This lid material is characterized in that

[0004] The microwave treatment packaging and steam-permeable label described in Patent Document 2 are packaging in which the steam-permeable label ensures the sealing of the container before microwave treatment (heating in a microwave oven), and allows steam inside the container to escape before the internal pressure becomes very high during microwave treatment.

[0005] The package described in Patent Document 2 comprises a microwave treatment container having a steam release opening, and a steam-permeable label having a label base material with a non-adhesive surface and an adhesive surface surrounding the non-adhesive surface, the steam-permeable label being affixed to the container via the adhesive surface so that the non-adhesive surface covers the steam release opening, the adhesive surface being formed from the back surface of an adhesive layer provided on the back side of the label base material, and the adhesive layer containing heat-expandable microparticles in part or all of the adhesive layer.

[0006] Both the lid material described in Patent Document 1 and the package described in Patent Document 2 relate to packages that can be heated in a microwave oven along with the container. However, for packaging containers that store food items that will not be used all at once, it would be very convenient if they could be resealed after opening, but the packages described in Patent Documents 1 and 2 do not mention anything about resealing. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2015-20781 [Patent Document 2] Japanese Patent Application Publication No. 2018-52513 Summary of the Invention [Problem to be solved by the invention]

[0008] The problem to be solved by the present invention is to provide a package that can be resealed after opening and that allows the container as a whole to be heated in a microwave oven. [Means for solving the problem]

[0009] As a means for solving the above problems, the invention described in claim 1 is an electron lens. a packaging body having a container body that can be heated in a microwave oven and a lid material that seals the opening of the container body, wherein the lid material has a U-shaped notch that serves as an outlet for removing the contents and a through-hole provided in a portion that separates from the bottom of the U-shape, and a resealing adhesive sheet member that covers the entire U-shaped notch and the through-hole is attached to the lid material, and the resealing adhesive sheet member is peeled upward from the bottom of the U-shaped notch and then resealed, whereby the through-hole acts as a steam vent hole when the packaging body is heated in a microwave oven.

[0010] The package according to the present invention can be resealed after opening, and after resealing, the container can be heated in a microwave oven.

[0011] Furthermore, the invention described in claim 2 is the packaging body described in claim 1, characterized in that the distance from the adhesive start point of the resealing adhesive sheet member to the through hole in the lid material is 5 mm or more and 35 mm or less.

[0012] Furthermore, the invention described in claim 3 is the packaging body described in claim 1 or 2, characterized in that the adhesive strength of the resealing adhesive sheet member is 5 N / 15 mm or more and 15 N / 15 mm or less at a peel speed of 300 mm / min and a 180° peel. [Effects of the Invention]

[0013] The package according to the present invention has a resealable adhesive sheet member that allows the opening to be resealed, so it can be used for applications in which the contents are not used up all at once. Furthermore, even if the container is heated in a microwave oven after resealing, the container will not explode because of the steam release hole.

[0014] As in the invention described in claim 2, by appropriately controlling the distance between the through hole provided in the lid material and the adhesive start portion of the resealing adhesive sheet member, a more stable steam passage operation can be obtained.

[0015] As in the invention described in claim 3, by setting the adhesive strength of the resealing adhesive sheet member within an appropriate range, smoother unsealing properties can be obtained. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a perspective view showing one embodiment of a package according to the present invention. [Figure 2] FIG. 2 is a schematic plan view of a resealing pressure-sensitive adhesive sheet member. [Figure 3] FIG. 3 is a schematic plan view of the lid member. [Figure 4] FIG. 4 is an explanatory plan view showing the state in which the resealing adhesive sheet member has been peeled off from the lid member and the container has been resealed. [Figure 5] FIG. 5 is a perspective explanatory view showing the state in which the resealed package is heated in a microwave oven. [Figure 6] FIG. 6 is an explanatory diagram of the distance (d) from the through-hole of the lid member to the adhesion start portion of the resealing adhesive sheet member. DETAILED DESCRIPTION OF THE INVENTION

[0017] The packaging body 1 according to the present invention will be described in detail below with reference to the drawings. FIG. 2 is a perspective view showing one embodiment of a packaging body 1 according to the invention. FIG. 2 is a plan view schematic diagram of a resealing adhesive sheet member 6. FIG. 3 is a plan view schematic diagram of a lid member 3. FIG. 4 is an explanatory plan view showing a state after peeling off the resealing adhesive sheet member 6 and resealing. The packaging body 1 according to the present invention will be described below with reference to these drawings.

[0018] The packaging body 1 according to the present invention is a packaging body having a microwaveable container body 2 and a lid member 3 that seals the opening of the container body 2. The lid member 3 has a U-shaped slit 4 that serves as an outlet for removing the contents, and a through-hole 7 provided in a portion separated from the bottom 5 of the U-shape.

[0019] A resealing adhesive sheet member 6 is attached to the lid material 3, covering the entire U-shaped notch 4 and the through hole 7. By peeling the resealing adhesive sheet member 6 upward from the bottom 5 of the U-shaped notch 4 and then resealing the package 1, the through hole 7 acts as a steam release hole when the package 1 is heated in a microwave oven.

[0020] 3 is a schematic plan view of the lid member 3. The lid member 3 is provided with a U-shaped notch 4 and a through-hole 7.

[0021] The U-shaped notch 4 provided in the lid member 3 may penetrate or partially penetrate the lid member 3. However, in the case of a partially penetrated notch, when the resealing adhesive sheet member 6 attached on the U-shaped notch 4 is peeled off, the notch 4 must tear to open the removal opening.

[0022] Although the shape of the through-hole 7 is an ellipse with the long side perpendicular to the peeling direction in FIG. 3, there are no particular restrictions on the shape of the through-hole 7.

[0023] FIG. 2 is a schematic plan view of a resealing adhesive sheet member 6. The resealing adhesive sheet member 6 generally has a gripping portion 9 so that it can be easily held by hand when starting to peel it off. The gripping portion 9 has no adhesiveness or is weakly adhesive, making it easy to trigger the start of peeling. The gripping portion 9 may be formed by forming a non-adhesive layer on top of an adhesive layer formed on the entire surface, or may be formed by not coating an adhesive on the base material from the beginning. The boundary between the gripping portion 9 and the adhesive processed portion becomes the adhesion initiation portion 8.

[0024] 4 is an explanatory plan view showing the state after the resealing adhesive sheet member 6 has been peeled off from the lid member 3 and resealed. When the resealing adhesive sheet member 6 is peeled off by hand by holding the tab portion 9, the through-hole 7 in the lid member is exposed, and the U-shaped notch 4 opens to form an opening. When the resealing adhesive sheet member is then resealed, water vapor can easily escape through the through-hole 7 when the package 1 is heated in a microwave oven.

[0025] 5 is an explanatory perspective view showing the state in which the resealed package 1 is heated in a microwave oven. The generated steam 10 is ejected from the through-holes 7 and released to the outside from the vicinity of the tab portion 9 of the resealing adhesive sheet member 6. Therefore, the container will not burst due to the pressure of the generated steam.

[0026] 6 is an explanatory diagram of the distance (d) from the through-hole 7 of the lid material 3 to the adhesion initiation portion 8 of the resealing adhesive sheet member 6. Since there is inevitably some variation in the attachment position of the resealing adhesive sheet member 6 to the lid material 3, if the distance (d) is too short, there is a risk that the through-hole 7 of the lid material 3 will be exposed from the adhesion initiation portion 8 of the resealing adhesive sheet member 6.

[0027] Conversely, if the distance (d) is too long, the steam may not be released smoothly. Experiments have shown that a distance (d) between 5 mm and 50 mm can be expected to provide a more stable steam flow.

[0028] Regarding the adhesive strength of the resealing adhesive sheet member 6, if the adhesive strength is too strong it will be difficult to peel off, whereas if the adhesive strength is too weak it may become impossible to open the lid material.

[0029] It has been found that the adhesive strength of the resealing adhesive sheet member 6 is more preferably 5 N / 15 mm or more and 15 N / 15 mm or less at a peel speed of 300 mm / min and a 180° peel angle.

[0030] There are no particular restrictions on the material, shape, molding method, etc. of the container body 2, as long as it has a shape with a flange that can be hermetically sealed with the lid member 3. For example, it may be a tray-shaped container formed by vacuum / compressed air molding of a synthetic resin sheet, a cup-shaped container formed by injection molding of a synthetic resin, or a paper container formed into a tray or cup shape. However, the flange surface must be made of a heat-sealable material so that the lid member 3 can be sealed.

[0031] There are no particular restrictions on the layer structure of the lid material 3, as long as it has a sealant layer on the inner surface for heat sealing to the flange portion of the container body 2. Various synthetic resin sheets and papers can be used in combination.

[0032] The layer structure of the resealing adhesive sheet member 6 requires a base layer and an adhesive layer, but there are no particular restrictions on the layer structure of the base layer. Various synthetic resin sheets and papers can be used in combination.

[0033] A gas barrier layer can also be provided on the container body 2, the lid member 3, and the resealing adhesive sheet member 6. The provision of a gas barrier layer improves the shelf life of the contents. However, because the container needs to be heated in a microwave oven, metal foils such as aluminum foil cannot be used. The packaging body according to the present invention will be described in more detail below based on examples. [Example]

[0034] The container body was made by vacuum-pressure forming a three-layer sheet of polypropylene resin / ethylene vinyl alcohol copolymer resin / polypropylene resin, as shown in Figure 1. The container dimensions were 130 mm x 250 mm x 50 mm in outer dimensions, and 120 mm x 240 mm in outer dimensions at the bottom.

[0035] The lid material was a laminate sheet of polyethylene terephthalate resin (thickness 12 μm) and unstretched polypropylene resin (thickness 50 μm). A U-shaped cut was made in the lid material as shown in Figure 2. The width of the U-shape was 80 mm. The dimensions of the oval through-hole were a major axis of 30 mm and a minor axis of 10 mm.

[0036] The resealing adhesive sheet member used was an adhesive sheet with a layer structure of polyvinylidene chloride coated (K-coated) stretched polypropylene resin film (thickness 20 μm) / adhesive / stretched polypropylene resin film (thickness 50 μm) / adhesive, as shown in Figure 2. The dimensions were 105 mm x 200 mm.

[0037] The distance (d) from the adhesive start point of the resealable adhesive sheet member to the through-hole in the lid material was varied from 2 mm to 38 mm, and 10 samples were prepared for each of Examples 1 to 7. 50 g of curry was placed in each sample, which was then opened and resealed, and heated in a 600 W microwave oven to check its vapor permeability. The results are summarized in Table 1.

[0038] [Table 1]

[0039] From the results in Table 1, when the distance (d) is 5mm to 35mm, more stable vapor permeability is achieved. It is clear that this can be expected. [Explanation of symbols]

[0040] 1...packaging 2. Container body 3...Lid material 4. U-shaped notch 5. U-shaped bottom 6. Re-sealing adhesive sheet member 7. Through hole 8... Adhesive start part 9. Knob 10. Water vapor d: Distance from the adhesive start point to the through hole

Claims

1. A package having a container body that can be heated in a microwave oven and a lid material that seals the opening of the container body, The lid material has a U-shaped notch serving as an outlet for contents and a through-hole provided in a portion separated from the bottom of the U-shape, a resealing adhesive sheet member that covers the U-shaped notch and the entire through-hole is attached to the lid member; The resealing adhesive sheet member is peeled upward from the bottom of the U-shaped notch, and then resealed, A packaging body characterized in that the through holes act as steam release holes when the packaging body is heated in a microwave oven.

2. 2. The package according to claim 1, wherein the distance from the adhesive start point of the resealing adhesive sheet member to the through hole of the lid member is 5 mm or more and 35 mm or less.

3. 3. The package according to claim 1, wherein the adhesive strength of the resealing adhesive sheet member is 5 N / 15 mm or more and 15 N / 15 mm or less at a peel speed of 300 mm / min and a 180° peel angle.

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