Package for microwave meal

Abstract

To provide a package for microwave meals which has a frame-shaped adhesive part that can be formed using a coating machine.SOLUTION: A package for microwave meals comprises a label having a planar substrate including a first direction X and a second direction Y which are perpendicular to each other, and a frame-shaped adhesive part provided on an inner surface of the substrate. The substrate includes a first substrate 40A, and a second substrate 40B that overlaps an outer surface of the first substrate 40A. The adhesive part is arranged in a frame shape by a pair of first adhesive parts 41A and 41A provided in the first direction X on the inner surface of both end parts 40Aa and 40Aa of the first substrate 40A in the second direction Y, and a pair of second adhesive parts 41B and 41B provided in the second direction Y on the inner surface of a pair of single-piece parts 40Ba and 40Ba of the second substrate 40B that are created by cutting out both side parts of the first substrate 40A in the first direction X (cutout parts 40Ab and 40Ab) leaving both end parts 40Aa and 40Aa of the first substrate 40A.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present invention relates to a package for a microwave-heated food that heats food inside using a microwave oven.

Background Art

[0002] As this type of package for a microwave-heated food, a container for a microwave-heated food in which a lid is provided with a vent hole and a label is attached to the lid so as to cover the vent hole is widely known. The label includes one having an adhesive portion on the entire inner surface of the base material (Patent Document 1) and one having a frame-shaped adhesive portion on the inner surface of the base material (Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the case of one having an adhesive portion on the entire inner surface of the base material, if it is a single adhesive portion, it can be formed using a coating machine (coater). On the other hand, in the case of one having a frame-shaped adhesive portion on the inner surface of the base material, it is difficult to form using a coating machine. Further, if a printing machine such as a gravure printing machine is used, it is possible to form a frame-shaped adhesive portion, but there is a risk that the coating amount of the adhesive is insufficient.

[0005] Therefore, in view of such circumstances, the present invention has been made, and an object thereof is to provide a package for a microwave-heated food having a frame-shaped adhesive portion that can be formed using a coating machine.

Means for Solving the Problems

[0006] The food packaging for microwave heating according to the present invention is composed of a packaging material, a ventilation part formed in the packaging material, and a label adhered to the outer surface of the packaging material so as to cover the ventilation part, wherein the label includes a planar base material including a first direction and a second direction perpendicular to each other, and a frame-shaped adhesive part provided on the inner surface of the base material. The base material includes a first base material and a second base material overlapped on the outer surface of the first base material. The adhesive part is provided in a frame shape by a pair of first adhesive parts provided along the first direction on the inner surfaces of both ends of the first base material in the second direction, and a pair of second adhesive parts provided along the second direction on the inner surfaces of a pair of single-piece parts of the second base material generated by cutting out both side parts of the first base material in the first direction leaving both ends of the first base material, or generated by the width of the first base material in the first direction being smaller than the width of the second base material in the first direction. It is a food packaging for microwave heating.

[0007] Here, as an aspect of the food packaging for microwave heating according to the present invention, the thickness of the second base material is smaller than the thickness of the first base material. Such a configuration can be adopted.

[0008] Also, as another aspect of the food packaging for microwave heating according to the present invention, the adhesive part is a strong adhesive, and the adhesive strength of the first adhesive part is greater than the adhesive strength of the second adhesive part. Such a configuration can be adopted.

[0009] Also, as another aspect of the food packaging for microwave heating according to the present invention, the single-piece part of the second base material includes a notch recessed in the first direction. Such a configuration can be adopted.

[0010] Also, as yet another aspect of the food packaging for microwave heating according to the present invention, the base material is rectangular with four sides along the first direction and the second direction. The adhesive part is in the shape of a square frame along each side of the base material. A configuration with... can be adopted.

[0011] Further, as still another aspect of the packaging body for a microwave-heated food according to the present invention, The frame inner region inside the adhesive part of the base material is provided with a ventilation part. A configuration with... can be adopted.

Advantages of the Invention

[0012] According to the present invention, the adhesive part is provided in a frame shape by a pair of first adhesive parts provided on the first base material and a pair of second adhesive parts provided on the second base material. And the first adhesive part can be formed on the first base material using a coating machine, and the second adhesive part can be formed on the second base material using a coating machine. Therefore, according to the present invention, a frame-shaped adhesive part can be formed using a coating machine.

Brief Description of the Drawings

[0013]

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DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, a container for an electronically heated food having a steam discharge structure (hereinafter simply referred to as "container") will be described.

[0015] As shown in FIGS. 1 and 2, the container 1 includes a container body 2, a lid 3, and a label 4. The container body 2 has a flange portion 20 at the opening periphery. The lid 3 is joined to the flange portion 20 to close the opening of the container body 2. The lid 3 has a first vent portion 30. The label 4 is attached to the outer surface of the lid 3 so as to cover the first vent portion 30. The label 4 has a second vent portion 43.

[0016] The container body 2 is formed by thermoforming a plastic sheet through sheet forming methods such as vacuum forming, pressure air forming, vacuum-pressure air forming, double-sided vacuum forming, hot plate forming, etc. The plastic sheet is, for example, a plastic sheet such as polystyrene (PS), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC), etc. Alternatively, the container body 2 may be formed by various known forming methods such as injection molding and foam molding. Also, the container body 2 can adopt various known containers such as paper, a laminate of paper and a plastic sheet, a foamed resin, and metal.

[0017] The lid 3 includes a lid body 3A and a grip piece 3B. The lid body 3A has the same shape as the outer edge of the flange portion 20. Since the flange portion 20 is annular, the lid body 3A is circular. When the flange portion 20 is, for example, a square-shaped angular ring, the lid body 3A is, for example, square-shaped. The grip piece 3B is a portion that protrudes from the lid body 3A and becomes a portion that protrudes from the flange portion 20 when the lid 3 is joined to the container body 2. When opening the lid 3, the grip piece 3B is grasped and peeled off from the flange portion 20.

[0018] The lid 3 is made of a flexible sheet having adhesiveness or heat weldability on its inner surface. The lid 3 is a lid for top sealing. Note that the top sealing refers to the situation where after the sheet of the lid 3 is placed over the opening of the container body 2, the flange portion 20 and the sheet of the lid 3 are heat welded (annular joint portion 10). The sheet is a plastic sheet having heat weldability such as polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), or stretched nylon (ONY). Alternatively, the sheet is a laminated sheet of two or more types of plastic sheets. As one form of the laminated sheet, the sheet is formed by laminating a base material layer and an easy peel layer in order from the outer surface side. For example, polyethylene terephthalate (PET) is used as the base material layer. For example, an easy peel film is used as the easy peel layer. Also, the sheet can adopt various known sheets such as a paper sheet having adhesiveness or heat weldability on its inner surface, a laminated sheet of a paper sheet and a plastic sheet, or a laminated sheet including a metal layer. Note that the "sheet" is not defined by thickness and is a concept including a film (the same applies hereinafter).

[0019] As shown in Fig. 3(a), the first vent portion 30 is formed by a U-shaped cut line 31. The cut line 31 is a full cut line penetrating the lid 3. By forming the cut line 31, a free piece 32 is formed with the cut line 31 as the outer contour line, the portion between both end points of the cut line 31 as the fixed end, and the central portion side of the cut line 31 as the free end. The pair of cut lines 31 are arranged symmetrically with respect to a line.

[0020] <Embodiment 1 of Label 4> As shown in Fig. 3(b), the label 4 includes a base material 40 and an adhesive portion 41. The base material 40 has a planar shape including a first direction X and a second direction Y that are perpendicular to each other. The base material 40 has a rectangular shape with four sides along the first direction X and the second direction Y. The adhesive portion 41 is provided in a frame shape on the inner surface of the base material 40. The adhesive portion 41 has a square frame shape along each side of the base material 40. The inner frame region 42 of the base material 40 inside the adhesive portion 41 is a non-adhesive region (non-adhesive portion) having no adhesiveness.

[0021] Note that the label 4 includes a printing layer. The printing layer is formed on the outer surface of the base material 40. The printing layer is for displaying product information or precautions during heating using a microwave oven. Also, the printing layer may be formed for pitch management during manufacturing.

[0022] The second ventilation part 43 is formed in the frame inner region 42. The second ventilation part 43 is provided so as to partially overlap with the first ventilation part 30 or not to overlap with the first ventilation part 30. The adhesive part 41 is provided so as to surround the first ventilation part 30 and the second ventilation part 43.

[0023] The second ventilation part 43 is composed of X-shaped or +-shaped cut lines (first cut line 44, second cut line 46). The first cut line 44 is a full cut line that penetrates the base material 40. By forming the first cut line 44, a free piece 45 is formed with the first cut line 44 as the outer contour line, the adjacent endpoints of the first cut line 44 as the fixed ends, and the central part side of the first cut line 44 as the free end. That is, four free pieces 45,... are formed around the central part side of the first cut line 44. The second cut line 46 is the same as the first cut line 44 except that it has a smaller shape than the first cut line 44. A plurality of first cut lines 44,... are two-dimensionally arranged with intervals between them, and a plurality of second cut lines 46,... are two-dimensionally arranged with intervals between them so as not to overlap any of the first cut lines 44. More specifically, a plurality of columns of first cut lines 44,... arranged at a predetermined interval in the first direction X are arranged in a plurality of rows at a predetermined interval in the second direction Y, and a plurality of columns of second cut lines 46,... arranged at a predetermined interval in the first direction X are arranged between the rows of the plurality of first cut lines 44,....

[0024] As shown in FIGS. 4 and 5, the base material 40 includes a first base material 40A and a second base material 40B. The base material 40 is a laminate in which the second base material 40B is overlapped and adhered to the outer surface of the first base material 40A. The widths of the first base material 40A and the second base material 40B in the first direction X and the heights in the second direction Y are the same. Therefore, the four sides of the first base material 40A and the four sides of the second base material 40B coincide. However, the first base material 40A and the second base material 40B do not have exactly the same outer shape because the first base material 40A has a notch 40Ab and the second base material 40B has a notch 47.

[0025] Each of the first base material 40A and the second base material 40B is a plastic sheet such as polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), or stretched nylon (ONY). As an example, the first base material 40A is a plastic sheet of polyethylene terephthalate (PET), and the second base material 40B is a plastic sheet of stretched polypropylene (OPP). However, the first base material 40A and the second base material 40B can be individually selected from these materials. Alternatively, each of the first base material 40A and the second base material 40B is a laminated sheet of two or more plastic sheets. Also, each of the first base material 40A and the second base material 40B can adopt various known sheets such as a paper sheet, a laminated sheet of a paper sheet and a plastic sheet, or a laminated sheet including a metal layer. Each of the first base material 40A and the second base material 40B is a non-thermally shrinkable sheet that does not have thermal shrinkability.

[0026] The thickness of the second base material 40B is smaller than the thickness of the first base material 40A. As an example, while the thickness of the first base material 40A is 50 μm, the thickness of the second base material 40B is 20 μm. Thereby, the second base material 40B is more flexible than the first base material 40A. However, the thickness of the second base material 40B may be the same as the thickness of the first base material 40A, or may be larger than the thickness of the first base material 40A.

[0027] The adhesion part 41 includes a pair of first adhesion parts 41A, 41A and a pair of second adhesion parts 41B, 41B. The pair of first adhesion parts 41A, 41A are parts along the two opposing sides of the base material 40 in the second direction Y. The pair of second adhesion parts 41B, 41B are parts along the two opposing sides of the base material 40 in the first direction X. Thereby, the adhesion part 41 has a square frame shape along each side of the base material 40.

[0028] The pair of first adhesion parts 41A, 41A are provided along the first direction X on the inner surfaces of both end parts 40Aa, 40Aa of the first base material 40A in the second direction Y. Each first adhesion part 41A has a rectangular shape (strip shape) that is long in the first direction X, and is provided from one side edge of the base material 40 in the first direction X to the other side edge.

[0029] The pair of second adhesion parts 41B, 41B are provided along the second direction Y on the inner surfaces of a pair of single-piece parts 40Ba, 40Ba of the second base material 40B. More specifically, although the adhesion part is provided on the entire inner surface of the second base material 40B, only the inner surfaces of the pair of single-piece parts 40Ba, 40Ba are exposed on the inner surface side of the label 4, so the adhesion part of this exposed part becomes the pair of second adhesion parts 41B, 41B. The other adhesion parts of the second base material 40B are used for adhesion to the first base material 40A.

[0030] The pair of single-piece parts 40Ba, 40Ba are configured by notching (notch parts 40Ab, 40Ab) the both side parts of the first base material 40A in the first direction X, leaving both end parts 40Aa, 40Aa of the first base material 40A. Each notch part 40Ab has a rectangular shape (strip shape) that is long in the second direction Y. Thereby, each single-piece part 40Ba and each second adhesion part 41B have a rectangular shape (strip shape) that is long in the second direction Y, and are provided from the inner edge of one first adhesion part 41A to the inner edge of the other first adhesion part 41A.

[0031] Note that both or either one of the pair of single-piece parts 40Ba, 40Ba includes a notch part 47 that is recessed in the first direction X. The notch part 47 has a shape (for example, V-shaped) in which the depth (cutting amount) increases as it goes toward the center of the label 4 in the second direction Y.

[0032] The first adhesive portion 41A and the second adhesive portion 41B are each configured using a strong adhesive so that when heating food in the container 1 using a microwave oven, the label 4 will not be peeled off from the lid 3 due to an increase in the internal pressure inside the container 1 or the generated steam, or so that a person cannot easily peel off the label 4. The adhesive is an adhesive such as an acrylic adhesive, a rubber adhesive, a silicone adhesive, a urethane adhesive, a polyester adhesive, a polyvinyl ether adhesive, an emulsion adhesive, a solvent adhesive, or a hot melt adhesive.

[0033] In particular, the first adhesive portion 41A is configured using an ultra-strong adhesive. That is, the adhesive strength of the first adhesive portion 41A is greater than the adhesive strength of the second adhesive portion 41B. However, the adhesive strength of the first adhesive portion 41A may be the same as the adhesive strength of the second adhesive portion 41B when the first adhesive portion 41A and the second adhesive portion 41B are configured using the same adhesive, or may be smaller than the adhesive strength of the second adhesive portion 41B. That is, the adhesive strength of the first adhesive portion 41A may be different from or the same as the adhesive strength of the second adhesive portion 41B.

[0034] The container 1 and the label 4 are configured as described above. Next, a method for manufacturing the label 4 will be described.

[0035] The method for manufacturing the label 4 is a step of applying an adhesive along the longitudinal direction of the first base material web at two corresponding positions on the inner surface of the long first base material web, a step of bonding the first base material web to a long separator on the inner surface, a step of semi-punching the first base material on the separator and removing unnecessary portions, a step of applying an adhesive to the entire inner surface of the long second base material web, a step of bonding the second base material web to the separator on the inner surface, a step of semi-punching the second base material on the separator and removing unnecessary portions.

[0036] Specifically, the manufacturing method of the label 4 includes the first to eighth steps described below. This manufacturing method is also applicable to the manufacturing of the label 4 according to Embodiment 2 and Embodiment 3 described later.

[0037] As shown in FIG. 6, in the first step, while the long first base material web 40AX is being conveyed, the adhesive 41X is applied along the longitudinal direction of the first base material web 40AX at two corresponding positions on the inner surface of the first base material web 40AX. For the application, coating machines such as a roll coater, a knife coater, a roll knife coater, an air knife coater, a die coater, a bar coater, a gravure coater, and a curtain coater are used, and the adhesive 41X is continuously applied to the inner surface of the conveyed first base material web 40AX, dried as necessary, and a strip-shaped adhesive portion is formed.

[0038] In the second step, the first base material web 40AX is bonded to the long separator 5 on the inner surface. As shown in FIG. 7, in the third step, the first base material 40A is half-cut (half cut) on the separator 5 and unnecessary portions are removed.

[0039] In the fourth step, while the long second base material web 40BX is being conveyed, the adhesive 41X is applied along the longitudinal direction of the second base material web 40BX to the entire inner surface of the second base material web 40BX. The application method is the same as that for the first base material web 40AX described above.

[0040] In the fifth step, the second base material web 40BX is bonded to the separator 5 on the inner surface. At this time, the second base material web 40BX is overlapped and adhered on the first base material 40A. As shown in FIG. 8, in the sixth step, the second base material 40B is half-cut (half cut) on the separator 5 and unnecessary portions are removed.

[0041] In the seventh step, the first cut line 44 is formed in the second ventilation portion 43. In the eighth step, the second cut line 46 is formed in the second ventilation portion 43. The seventh step and the eighth step may be simultaneous.

[0042] Through the above steps, the label 4 is manufactured. Note that the first to third steps and the fourth step are independent of each other, and the order of the steps does not matter.

[0043] The container 1 is distributed as a product. And when a purchaser eats food, the food in the container 1 is heated using a microwave oven. During heating, the generated steam is discharged to the outside through a path passing from the first ventilation part 30 to the second ventilation part 43.

[0044] Also, after heating, the internal pressure of the container 1 decreases, but outside air is taken into the container 1 through a path passing from the second ventilation part 43 to the first ventilation part 30, and the decrease in the internal pressure of the container 1 is alleviated.

[0045] As described above, according to the label 4 and the manufacturing method thereof according to Embodiment 1, the adhesive part 41 is provided in a frame shape by a pair of first adhesive parts 41A, 41A provided on the first base material 40A and a pair of second adhesive parts 41B, 41B provided on the second base material 40B. And the first adhesive part 41A can be formed on the first base material 40A using a coating machine, and the second adhesive part 41B can be formed on the second base material 40B using a coating machine. Therefore, according to the label 4 and the manufacturing method thereof according to Embodiment 1, a frame-shaped adhesive part 41 can be formed using a coating machine.

[0046] Also, according to the label 4 according to Embodiment 1, the second base material 40B is thinner and more flexible than the first base material 40A. Thereby, the single-piece part 40Ba of the second base material 40B stacked on the first base material 40A sinks into the cut part 40Ab of the first base material 40A, and the inner surface of the first base material 40A and the inner surface of the single-piece part 40Ba of the second base material 40B are appropriately flush. For this reason, according to the label 4 according to Embodiment 1, the entire frame-shaped adhesive part 41 can adhere to the outer surface of the lid 3, and the peripheries of the first ventilation part 30 and the second ventilation part 43 can be appropriately sealed.

[0047] Moreover, according to the label 4 according to Embodiment 1, the adhesive portion 41 has strong adhesiveness, and the adhesive strength of the first adhesive portion 41A is greater than the adhesive strength of the second adhesive portion 41B. As a result, when the microwave heating has a high output, a large amount of water vapor is generated, but the second adhesive portion 41B (a part thereof) peels off to release the water vapor. However, the first adhesive portion 41A remains adhered to the label 4. Therefore, according to the label 4 according to Embodiment 1, it is possible to suitably prevent the container body 2 and the lid 3 from bursting due to the increase in the internal pressure, and also to prevent the label from being completely peeled off from the lid 3.

[0048] Moreover, according to the label 4 according to Embodiment 1, a notch 47 is formed in the single-layer portion 40Ba of the second base material 40B (as a result, the side portion of the label 4 in the first direction X). Therefore, according to the label 4 according to Embodiment 1, the label 4 can be smoothly peeled off from the separator 5.

[0049] Moreover, according to the steam discharge structure according to the present embodiment, it has a path passing from the first ventilation portion 30 through the second ventilation portion 43. Therefore, according to the steam discharge structure according to the present embodiment, during heating, the steam can be reliably discharged, and thus, the bursting of the container 1 can be suitably prevented.

[0050] Moreover, according to the steam discharge structure according to the present embodiment, the path passing from the second ventilation portion 43 through the first ventilation portion 30 remains open. Therefore, according to the steam discharge structure according to the present embodiment, after stopping the heating, outside air can be taken into the container 1, and thus, the deformation due to the decrease in the internal pressure of the container 1 can be suitably prevented.

[0051] Moreover, according to the steam discharge structure according to the present embodiment, the adhesive portion 41 of the label 4 is in a frame shape that surrounds and seals the first ventilation portion 30 of the lid 3 and the second ventilation portion 43 of the label 4. Therefore, according to the steam discharge structure according to the present embodiment, during heating, it is possible to suitably prevent the juice or the like inside the container 1 from leaking out through the first ventilation portion 30 and soiling the outer surface of the lid 3.

[0052] <Embodiment 2 of Label 4> Next, the label 4 according to Embodiment 2 will be described. In the following, the differences from the label 4 according to Embodiment 1 will be described, and the same points will be omitted from the description as being the same as the description of the label 4 according to Embodiment 1.

[0053] The difference lies in the method of forming a pair of single-piece portions 40Ba and 40Ba of the second base material 40B. In Embodiment 1, a pair of single-piece portions 40Ba and 40Ba are formed by forming a pair of cutout portions 40Ab and 40Ab on the left and right of the first base material 40A, whereas in Embodiment 2, as shown in FIGS. 9 and 10, a pair of single-piece portions 40Ba and 40Ba are formed by making the width of the first base material 40A in the first direction X smaller than the width of the second base material 40B in the first direction X. More specifically, in the first direction X, each side portion of the second base material 40B is protruded from each side edge of the first base material 40A.

[0054] Each single-piece portion 40Ba and each second adhesive portion 41B are provided along the second direction Y, are rectangular (strip-shaped) and long in the second direction Y, and are provided from one edge to the other edge of the base material 40 in the second direction Y.

[0055] Thus, the label 4 according to Embodiment 2 also exhibits the same operational effects as those of the label 4 according to Embodiment 1.

[0056] <Embodiment 3 of Label 4> Next, the label 4 according to Embodiment 3 will be described. In the following, the differences from the label 4 according to Embodiment 1 will be described, and the same points will be omitted from the description as being the same as the description of the label 4 according to Embodiment 1.

[0057] The difference lies in the outer shape of the label 4 (substrate 40 (first substrate 40A, second substrate 40B)). In Embodiment 1, it is rectangular, while in Embodiment 3, as shown in FIGS. 11 and 12, it has a shape (oval shape) with both sides of a circle cut off. However, the outer shape of the label 4 is not limited to these, and various shapes such as circular, elliptical, pentagonal, hexagonal, etc. can be adopted.

[0058] Thus, the label 4 according to Embodiment 3 also exhibits the same effects as those of the label 4 according to Embodiment 1.

[0059] It should be noted that the present invention is not limited to the above embodiments, and various modifications are possible without departing from the gist of the present invention.

[0060] In the above embodiment, the adhesive portion is provided on the entire inner surface of the second substrate 40B. However, the present invention is not limited to this. The second substrate may have at least only the second adhesive portion on the premise that it is joined to the first substrate. As an example, the second substrate may have a pair of second adhesive portions at both ends, similar to the first substrate, and may be configured to be overlapped and joined in a state rotated 90 degrees with respect to the first substrate.

[0061] Also, in the above embodiment, the first substrate 40A and the second substrate 40B have the same outer circumferential shape (rectangular or circular) and their outer edges coincide. However, the present invention is not limited to this. The second substrate may have at least one of the width in the first direction and the height in the second direction larger than that of the first substrate.

[0062] Also, in the above embodiment, the first adhesive portion 41A and the second adhesive portion 41B are each formed using a coating machine. However, the present invention is not limited to being formed using a coating machine just because it can be formed using a coating machine. For example, the first adhesive portion and the second adhesive portion may be formed using a printing machine.

[0063] In the above embodiment, the packaging for a microwave-heated food is the container 1, and the packaging material to which the label 4 is to be attached is the lid 3 for top sealing. However, the present invention is not limited to this. For example, the packaging for a microwave-heated food may be a flexible package, and the packaging material to which the label is to be attached may be a sheet constituting the flexible package. Further, the packaging material to which the label is to be attached is not limited to a flexible packaging material, and may be a sheet molded article having a fixed shape such as a lid fitted to a container.

[0064] Also, in the above embodiment, the forms of the first vent portion 30 and the second vent portion 43 are merely examples. The first vent portion and the second vent portion can be appropriately selected from various known configurations such as cut lines in a linear shape, an arc shape, a U shape, a C shape, a + shape, an X shape, etc., and through holes such as circular holes and square holes.

[0065] Also, in the above embodiment, the adhesive portion 41 has strong adhesiveness. However, the present invention is not limited to this. For example, a part of the frame-shaped adhesive portion may have weak adhesiveness, and during heating, this part may peel off to discharge steam. In this case, the second vent portion may or may not be provided.

[0066] Also, in the above embodiment, the label 4 is applied to the steam discharge structure. However, the present invention is not limited to this. The label may be a label for general use that is not a steam discharge label.

Explanation of reference numerals

[0067] 1…Container, 10…Annular joint, 2…Container body, 20…Flange part, 3…Cover, 3A…Cover body, 3B…Lifting piece, 30…First ventilation part, 31…Cutting line, 32…Free piece, 4…Label, 40…Base material, 40A…First base material, 40Aa…End part, 40Ab…Notch part, 40AX…First base material original web, 40B…Second base material, 40Ba…Single sheet part, 40BX…Second base material original web, 41…Adhesive part, 41A…First adhesive part, 41B…Second adhesive part, 41X…Adhesive, 42…Inner frame area (non - adhesive area, non - adhesive part), 43…Second ventilation part, 44…Cutting line (first cutting line), 45…Free piece, 46…Cutting line (second cutting line), 47…Cutting part, 5…Separator (release paper), X…First direction, Y…Second direction

Claims

1. A packaging material, a ventilation part formed in the packaging material, and a label adhered to the outer surface of the packaging material so as to cover the ventilation part, wherein the label includes a planar base material including a first direction and a second direction orthogonal to each other, and a frame-shaped adhesive part provided on the inner surface of the base material, the base material includes a first base material and a second base material overlapped on the outer surface of the first base material, the adhesive part is provided in a frame shape by a pair of first adhesive parts provided along the first direction on the inner surfaces of both ends of the first base material in the second direction, and a pair of single-piece parts of the second base material generated by cutting out both side parts of the first base material in the first direction leaving both ends of the first base material, or a pair of second adhesive parts provided along the second direction on the inner surfaces of a pair of single-piece parts of the second base material generated by the width of the first base material in the first direction being smaller than the width of the second base material in the first direction, a packaging body for a food heated in a microwave oven.

2. The thickness of the second base material is smaller than the thickness of the first base material The packaging body for a food heated in a microwave oven according to Claim 1.

3. The adhesive part is a strong adhesive, and the adhesive strength of the first adhesive part is greater than the adhesive strength of the second adhesive part The packaging body for a food heated in a microwave oven according to Claim 1 or Claim 2.

4. The single-piece part of the second base material includes a notch recessed in the first direction The packaging body for a food heated in a microwave oven according to Claim 1 or Claim 2.

5. The base material is rectangular with four sides along the first direction and the second direction, and the adhesive part is in a square frame shape along each side of the base material The packaging body for a food heated in a microwave oven according to Claim 1 or Claim 2.

6. The frame inner region inside the adhesive part of the base material includes a ventilation part The packaging body for a food heated in a microwave oven according to Claim 1 or Claim 2.

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