Container body and packaging container

Abstract

To provide a container body for a packaging container, which enables fine molding even when an expansion ratio of a foam resin sheet is high.SOLUTION: A lid body of this packaging container includes a top surface part, side surface parts that extend downward from the top surface part, a protrusion part that is positioned between two side surface parts to protrude outside from the side surface parts in a plan view, and a groove part that is provided to surround the side surface parts and the protrusion part. The groove part includes an inner peripheral wall that includes parts of the side surface parts and protrusion parts, and an outer peripheral wall that faces the inner peripheral wall. The outer peripheral wall includes a fitting part that fits the container body of the packaging container.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION An embodiment of the present invention relates to a container body of a packaging container. Also, an embodiment of the present invention relates to a packaging container. [Background technology]

[0002] In supermarkets, convenience stores, and other stores, foods such as sushi and sashimi are displayed in packaging containers. Packaging foods in packaging containers allows multiple packaging containers to be stacked on top of each other for display, making it possible to provide food to a large number of consumers. The shape of the packaging container can vary depending on the food to be packed. For example, when packing sushi as food in a packaging container, the packaging container often has a shape in which the bottom of the container body is raised (a so-called hakama shape), as in Patent Document 1.

[0003] On the other hand, in recent years, from the viewpoint of reducing plastic consumption, packaging containers using foamed resin sheets have been attracting attention. For example, in Patent Document 2, a foamed resin sheet is used for the container body of a skirt-shaped packaging container. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2022-136509 [Patent Document 2] Japanese Patent Publication No. 2022-074628 Summary of the Invention [Problem to be solved by the invention]

[0005] Increasing the expansion ratio of a container body made of a foamed resin sheet can reduce the amount of material used in the container body and make it lighter. However, increasing the expansion ratio increases the thickness of the foamed resin sheet that makes up the container body, making it difficult to mold the container body into a fine shape. For example, if the thickness of the foamed sheet increases and it becomes difficult to release the fitting portion provided on the container body from the mold, the defective rate of the container body increases. As a result, there are problems such as a decrease in the manufacturing yield of the container body and an increase in manufacturing costs.

[0006] In view of the above problems, one object of one embodiment of the present invention is to provide a container body for a packaging container that can be finely molded even when the expansion ratio of the foamed resin sheet is high. Another object of one embodiment of the present invention is to provide a packaging container that includes a container body for a packaging container that can be finely molded even when the expansion ratio of the foamed resin sheet is high, and a lid made of a non-foamed resin sheet. [Means for solving the problem]

[0007] A container body according to one embodiment of the present invention is a container body made of a foamed resin sheet and fitted with a lid, and includes a bottom, an inner wall extending upward from the bottom, an upper edge connected to the inner wall, an outer wall connected to the upper edge and extending downward from the upper edge outside the inner wall, and legs connected to the outer wall, the lower ends of the legs being located below the bottom, and the outer wall at a position corresponding to the corner of the bottom is provided with a fitting portion that fits with the lid, and the fitting portion is connected to an upper region that is located above the fitting portion and curved so as to be recessed from the outer wall.

[0008] The radius of curvature of the upper region may be R0.8 or more and R10.0 or less.

[0009] The fitting portion may further be connected to a lower region that is located below the fitting portion and that is inclined with respect to a direction substantially parallel to the flat surface of the bottom portion.

[0010] The angle formed by the lower region with respect to a direction substantially parallel to the upper surface of the bottom portion may be greater than 0° and not greater than 60°.

[0011] The foamed resin sheet may have a thickness of 0.8 mm or more and 5.0 mm or less, and an expansion ratio of the foamed resin sheet may be 3 times or more and 20 times or less.

[0012] Linear or striped irregularities may be provided on the lower end of the inner circumferential wall at positions corresponding to the corners of the bottom.

[0013] Linear or striped concave and convex shapes may be provided on the lower ends of the legs at positions corresponding to the corners of the bottom.

[0014] A packaging container according to one embodiment of the present invention includes the above-described container body, and a lid that fits into the fitting portion of the container body and is made of a non-foamed resin sheet. [Effects of the Invention]

[0015] The container body of the packaging container according to one embodiment of the present invention can be finely molded even when the foamed resin sheet has a high expansion ratio. This improves the manufacturing yield of the container body and reduces manufacturing costs. Furthermore, because the expansion ratio of the foamed resin sheet of the container body can be increased, the amount of material used can be reduced, making the container body lighter. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a perspective view showing the configuration of a packaging container in which a lid body and a container body are fitted together in one embodiment of the present invention. [Figure 2] 1 is a perspective view showing the configuration of a packaging container in which a lid body and a container body are separated in one embodiment of the present invention. [Figure 3] FIG. 2 is a top view showing the configuration of a container body in one embodiment of the present invention. [Figure 4] FIG. 2 is a bottom view showing the configuration of a container body in one embodiment of the present invention. [Figure 5]FIG. 2 is a first side view showing the configuration of a container body in one embodiment of the present invention. [Figure 6] FIG. 2 is a second side view showing the configuration of the container body in one embodiment of the present invention. [Figure 7] FIG. 2 is an end view showing the structure of the vicinity of the fitting portion of the container body in one embodiment of the present invention. [Figure 8] FIG. 2 is an end view showing a configuration in which the lid and the container body are fitted together in one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments of the invention disclosed in this application will be described with reference to the drawings. However, the present invention can be embodied in various forms without departing from the spirit of the invention, and should not be construed as being limited to the description of the embodiments exemplified below.

[0018] In order to clarify the description, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment, but this does not limit the interpretation of the present invention. Furthermore, in the specification and drawings, components having the same functions as components explained with reference to previous drawings may be assigned the same reference numerals, and duplicate explanations may be omitted.

[0019] In the specification, the terms "above" and "below" used to define the positional relationship between a certain component and another component may refer not only to a case where the other component is located directly above or below the certain component, but may also include a configuration in which there is yet another component interposed between them.

[0020] <1. Configuration of packaging container 10> Fig. 1 is a perspective view showing the configuration of a packaging container 10 in which a lid body 100 and a container body 200 are fitted together. Fig. 2 is a perspective view showing the configuration of a packaging container 10 in which the lid body 100 and the container body 200 are separated from each other.

[0021] As shown in Figures 1 and 2, the packaging container 10 includes a lid 100 and a container body 200. The lid 100 can be fitted to the container body 200. After contents such as food or prepared food are placed in the container body 200, the lid 100 can be fitted to the container body 200, allowing the packaging container 10 with the contents placed therein to be displayed in a store. Furthermore, by placing the contents in the packaging container 10, the contents can be managed hygienically for each packaging container 10.

[0022] The lid body 100 is formed by molding (for example, vacuum forming, pressure forming, or hot plate forming) using a non-foamed resin sheet. The lid body 100 is preferably translucent so that consumers can see the contents contained in the packaging container 10. Materials that can be used for the lid body 100 include, for example, polyester-based resins such as polyethylene terephthalate, olefin-based resins such as polyethylene or polypropylene, polyester-based resins such as polyethylene terephthalate, and polystyrene-based resins. The lid body 100 is also preferably heat-resistant. For example, when the packaging container 10 is to be heated in a microwave oven, the lid body 100 can also be made of a biaxially oriented polystyrene-based resin.

[0023] The top surface of the lid 100 has a flat surface. A fitting portion 110 that protrudes toward the inside of the lid 100 is provided on a side surface of the lid 100. The fitting portion 110 can also be described as a protrusion provided on the inside of the side surface. As will be described in detail below, the fitting portion 110 of the lid 100 fits into a fitting portion 260 of the container body 200, thereby sealing the packaging container 10. That is, when the lid 100 is placed above the container body 200 and a load is applied to the lid 100, the lid 100 and the container body 200 fit together via the fitting portions 110 and 260. The packaging container 10 has a so-called external fitting structure in which the lid 100 is fitted to the outside of the container body 200.

[0024] Furthermore, a convex body 120 that protrudes outward from the lid body 100 is provided on the side portion of the lid body 100. The position and number of the convex bodies 120 are not particularly limited. When multiple lid bodies 100 are stacked, the convex bodies 120 create a gap between two adjacent lid bodies 100, preventing the two adjacent lid bodies 100 from sticking together. Providing the convex body 120 on the lid body 100 makes it easy to remove one lid body 100 from the multiple stacked lid bodies 100.

[0025] The lid 100 is also provided with a peripheral edge 130 that forms the periphery of the lid 100. The peripheral edge 130 protrudes outward from the side surface of the lid 100 so as to be approximately parallel to the flat surface of the top surface of the lid 100.

[0026] The container body 200 is formed by molding (e.g., vacuum molding, pressure molding, or hot plate molding) using a foamed resin sheet. The thickness of the foamed resin sheet in the container body 200 after foaming is, for example, 0.8 mm to 5.0 mm, preferably 1.5 mm to 4.0 mm, and more preferably 1.8 mm to 3.3 mm. The expansion ratio is, for example, 3 to 20 times, preferably 4 to 18 times, and more preferably 5 to 15 times. Since the container body 200 is formed from a so-called highly foamed resin, it is lightweight and has excellent impact resistance. Examples of materials that can be used for the container body 200 include polyolefin resins and polystyrene resins. The container body 200 may also be formed from a laminated film of multiple materials. When the lid 100 is heat-resistant, the container body 200 is preferably heat-resistant as well. In this case, the material of the container body 200 may be, for example, a resin containing polyphenylene ether in a polystyrene-based resin.

[0027] The detailed configuration of the container body 200 will be described below.

[0028] 2. Configuration of the container body 200 3 to 6 are a top view, a bottom view, a first side view, and a second side view, respectively, showing the configuration of the container body 200. The container body 200 includes a bottom 210, an inner peripheral wall 220, an upper edge 230, an outer peripheral wall 240, and legs 250.

[0029] In the container body 200, the contents can be placed on the upper surface of the bottom 210. For example, if the contents are sushi, the upper surface of the bottom 210 preferably has a flat surface to prevent the sushi from crumbling. Furthermore, if the contents are sashimi, the upper surface of the bottom 210 preferably has not only a flat surface but also an inclined surface for serving the sashimi upright. Furthermore, a pattern with a concave-convex shape can be formed on the bottom 210. In this embodiment, as described above, the container body 200 is formed of a highly foamed resin, and therefore the thickness of the container body 200 is large. Therefore, by adjusting the depth or height of the concave-convex shape formed on the upper surface of the bottom 210, different patterns can be formed on the upper and lower surfaces of the bottom 210 (see FIGS. 3 and 4). Specifically, if deep recesses are formed on the upper surface of the bottom 210, convex portions corresponding to the recesses are formed on the lower surface of the bottom 210. On the other hand, if shallow recesses are formed on the upper surface of the bottom 210, convex portions corresponding to the recesses are not formed on the lower surface of the bottom 210.

[0030] In a plan view (see FIG. 3 or FIG. 4), the periphery of the bottom 210 has long sides, short sides perpendicular to the long sides, and corners connecting the long sides and the short sides. The corners may be curved or straight. That is, the bottom 210 has a substantially rectangular shape including short sides and long sides. However, the planar shape of the bottom 210 is not limited to this, and may be a substantially circular shape, a substantially elliptical shape, or a substantially polygonal shape such as a substantially triangular shape or a substantially pentagonal shape.

[0031] Note that the first side view in Figure 5 is a side view viewed from a plane parallel to the long side of the bottom 210, and the second side view in Figure 6 is a side view viewed from a plane parallel to the short side of the bottom 210.

[0032] The inner peripheral wall portion 220 is connected to the periphery of the bottom portion 210 and extends upward from the periphery of the bottom portion 210. The inner peripheral wall portion 220 is provided so as to surround the periphery of the bottom portion 210. The inner peripheral wall portion 220 may be provided perpendicular to the upper surface of the bottom portion 210 or may be provided so as to form an inclined surface. The inner peripheral wall portion 220 may also have steps, with multiple inclined surfaces formed at different angles. For example, the inner peripheral wall portion 220 may have multiple inclined surfaces whose inclination angle decreases upward from the bottom portion 210. In a packaging container 10 made of a foamed resin sheet, unevenness is relatively difficult to see. Therefore, for example, as shown in FIG. 3, linear or striped unevenness 221 may be formed on the lower end of the inner peripheral wall portion 220 at positions corresponding to the corners of the bottom portion 210. Such uneven shape 221 can give consumers a sense of three-dimensionality of the inside of the packaging container 10 without compromising the overall design of the packaging container 10. The uneven shape 221 at the lower end of the inner peripheral wall portion 220 may be formed not only at positions corresponding to the corners of the bottom portion 210 but also at positions corresponding to the long sides or short sides of the bottom portion 210.

[0033] The upper edge portion 230 is connected to the inner peripheral wall portion 220 and forms the upper edge of the packaging container 10. The upper edge portion 230 may have a flat surface or a curved surface. Furthermore, the height of the upper edge portion 230 is not constant over the entire upper edge of the packaging container 10, and may include portions of different heights. When the upper edge portion 230 includes portions of different heights, a concave rib is formed in the upper edge portion 230, thereby improving the rigidity of the container body 200 (particularly the upper edge portion 230).

[0034] The outer peripheral wall 240 is connected to the upper edge 230 and extends downward from the upper edge 230. That is, the outer peripheral wall 240 is provided on the outside of the inner peripheral wall 220. In the container body 200, the inner peripheral wall 220, the upper edge 230, and the outer peripheral wall 240 are formed in a substantially U-shape, which can improve the rigidity of the container body 200.

[0035] The outer peripheral wall 240 has fitting portions 260 recessed into the inner surface of the outer peripheral wall 240 at positions corresponding to the corners of the bottom 210. The fitting portions 260 can also be referred to as recesses provided in the outer peripheral wall 240. As described above, the fitting portions 260 of the container body 200 are fitted with the fitting portions 110 of the lid 100. Note that the fitting portions 260 may be provided not only at positions corresponding to the corners of the bottom 210, but also so as to extend to positions corresponding to the long or short sides of the bottom 210, as shown in FIGS. 5 and 6 .

[0036] The details of the structure in the vicinity of the fitting portion 260 will be described later.

[0037] The legs 250 are connected to the outer peripheral wall 240 and extend downward from the outer peripheral wall 240. The lower ends of the legs 250 protrude downward below the underside of the bottom 210. Therefore, the packaging container 10 has a shape in which the bottom 210 is raised by the legs 250, i.e., a so-called "hakama" shape. The legs 250 are provided so as to form a slope with respect to the underside of the bottom 210. Specifically, the legs 250 are formed with a slope that widens outward from above to below. Because the legs 250 have such a shape, the packaging containers 10 can be stacked and placed such that the upper edge 230 is housed inside the legs 250. Furthermore, the legs 250 can be formed with an uneven pattern. As described above, uneven shapes are relatively difficult to see in a packaging container 10 made of a foamed resin sheet. 5 and 6, for example, linear or striped uneven shapes 251 may be formed on the lower ends of the legs 250 at positions corresponding to the corners of the bottom 210. Such uneven shapes 251 can give consumers a sense of three-dimensionality on the outside of the packaging container 10 without compromising the overall design of the packaging container 10. Note that the uneven shapes 251 on the lower ends of the legs 250 may be formed not only at positions corresponding to the corners of the bottom 210 but also at positions corresponding to the long or short sides of the bottom 210.

[0038] <3. Structure in the vicinity of the fitting portion 260> Fig. 7 is an end view showing the structure of the container body 200 near the fitting portion 260. Specifically, Fig. 7 is an end view of the container body 200 cut along the A1-A2 line shown in Fig. 3. Fig. 8 is an end view showing the configuration in which the lid 100 and the container body 200 are fitted together.

[0039] 7, the fitting portion 260 is provided on the outer peripheral wall portion 240. For ease of explanation, the outer peripheral wall portion 240 is divided into two portions, one at the boundary of the fitting portion 260, and the other at the upper portion of the outer peripheral wall portion 240 below the fitting portion 260 is referred to as an upper region 241, and the other at the lower portion of the outer peripheral wall portion 240 below the fitting portion 260 is referred to as a lower region 242. The upper region 241 is connected to the upper edge portion 230, and the lower region 242 is connected to the leg portion 250.

[0040] The upper region 241 has a curved structure. The radius of curvature of the upper region 241 is, for example, R0.8 or more and R1.0 or less, preferably R1.5 or more and R9.0 or less, and more preferably R2.0 or more and R8.0 or less. By setting the radius of curvature of the upper region 241 within the above range, the distance from the upper edge 230 (more specifically, the upper edge of the container body 200) to the fitting portion 260 can be reduced, thereby making it easier for the lid 100 and the container body 200 to fit together. Note that the curved structure of the upper region 241 may include a flat surface in part.

[0041] The lower region 242 does not extend in a direction substantially parallel to the flat surface of the bottom 210 (a flat surface included in the upper or lower surface of the bottom 210), but extends at a predetermined angle from a direction substantially parallel to the flat surface of the bottom 210. The angle θ formed by the lower region 242 with respect to a direction substantially parallel to the flat surface of the bottom 210 is, for example, greater than 0° and less than 60°, preferably greater than 10° and less than 55°, and more preferably greater than 15° and less than 50°. By setting the angle θ of the lower region 242 within the above range, the opening of the fitting portion 260 can be widened, thereby facilitating the molding of the fitting portion 260 of the container body 200. The inclined surface of the lower region 242 may be curved from top to bottom.

[0042] Since the container body 200 formed from a highly foamed resin has a large thickness, it is difficult to mold it finely compared to a container body formed from a non-foamed resin or a low-foamed resin (for example, an expansion ratio of less than 5 times). Therefore, by employing the above-described structure in the vicinity of the fitting portion 260 in the container body 200, it is possible to facilitate molding of the fitting portion 260 in the container body 200 and to strengthen the fit between the fitting portion 110 of the lid 100 and the container body 200.

[0043] As described above, the lower region 242 has an inclined surface that is inclined relative to a direction substantially parallel to the flat surface of the bottom 210. Meanwhile, the peripheral edge 130 of the lid 100 is formed substantially parallel to the flat surface of the top surface of the lid 100, i.e., the flat surface of the bottom 210. Therefore, as shown in FIG. 8 , when the lid 100 and the container body 200 are fitted together, a gap is generated between the peripheral edge 130 of the lid 100 and the lower region 242 of the container body 200. In other words, the gap between the peripheral edge 130 and the lower region 242 becomes larger toward the outside of the peripheral edge 130.

[0044] Although the structure in which fitting portion 260 is provided on outer peripheral wall portion 240 has been described above, fitting portion 260 may be provided between outer peripheral wall portion 240 and leg portion 250. Even in this case, the above-described structure can be adopted for the region above and below the position where fitting portion 260 is provided.

[0045] As described above, in the packaging container 10 according to this embodiment, even when the container body 200 is made of a foamed resin sheet having a high expansion ratio and a large thickness, it is possible to form the fitting portion 260. This improves the manufacturing yield of the container body 200 and reduces manufacturing costs. Furthermore, because the expansion ratio of the foamed resin sheet of the container body 200 can be increased, the amount of material used can be reduced, and the weight of the container body 200 can be reduced.

[0046] Even if there are other effects and advantages different from those brought about by the aspects of the above-described embodiments, those that are clear from the description in this specification or that can be easily predicted by a person skilled in the art are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0047] 10: Packaging container, 100: Lid, 110: Fitting portion, 120: Convex body, 130: Peripheral edge portion, 200: Container body, 210: Bottom portion, 220: Inner peripheral wall portion, 221: Concave and recessed shape, 230: Upper edge portion, 240: Outer peripheral wall portion, 241: Upper region, 242: Lower region, 250: Leg portion, 251: Concave and recessed shape, 260: Fitting portion

Claims

1. A container body made of a foamed resin sheet and fitted with a lid, The bottom and an inner peripheral wall portion extending upward from the bottom; an upper edge portion connected to the inner circumferential wall portion; an outer peripheral wall portion connected to the upper edge portion and extending downward from the upper edge portion on the outer side of the inner peripheral wall portion; a leg portion connected to the outer peripheral wall portion, The lower ends of the legs are located lower than the bottom portion, a fitting portion that fits with the lid body is provided on the outer peripheral wall portion at a position corresponding to a corner of the bottom portion, The container body, wherein the fitting portion is connected to an upper region that is positioned above the fitting portion and curved so as to be recessed from the outer peripheral wall portion.

2. The container body according to claim 1 , wherein the radius of curvature of the upper region is R0.8 or more and R1.0 or less.

3. The container body according to claim 1 , wherein the fitting portion is further connected to a lower region that is located below the fitting portion and is inclined with respect to a direction substantially parallel to the flat surface of the bottom portion.

4. The container body according to claim 3 , wherein the angle formed by the lower region with respect to a direction substantially parallel to the upper surface of the bottom portion is greater than 0° and is not greater than 60°.

5. The foamed resin sheet has a thickness of 0.8 mm or more and 5.0 mm or less, 2. The container body according to claim 1, wherein the expansion ratio of the foamed resin sheet is 3 times or more and 20 times or less.

6. The container body according to claim 1 , wherein a linear or striped uneven shape is provided on the lower end of the inner circumferential wall portion at the position corresponding to the corner of the bottom portion.

7. The container body according to claim 1 , wherein linear or striped unevenness is provided on the lower ends of the legs at the positions corresponding to the corners of the bottom portion.

8. The container body according to any one of claims 1 to 7, a lid body made of a non-foamed resin sheet and fitted into the fitting portion of the container body.

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