Container and container with content

Abstract

To provide a container and a container with a content capable of suppressing deformation of a flange part even if an internal pressure increases during heating in a microwave oven.SOLUTION: A container 11 is sealed with a lid 12 having a breaking part 12a that breaks due to an increase in an internal pressure, and comprises: a body part 21 having at least an edge extending in one direction; a bottom part 22 provided at a lower end of the body part 21; and a flange 23 having a flange part 23a provided at an upper end of the body part 21 and to which the lid 12 is sealed, and a skirt part 23b extending downward from the flange part 23a.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a container for containing contents and a container containing contents.

Background Art

[0002] Conventionally, a container that contains contents and heats the contents in a sealed state using a microwave oven has been known. However, when such a container heats the contents using a microwave oven, the internal pressure increases. For this reason, containers equipped with means for automatically discharging steam and reducing the internal pressure during microwave heating are also known.

[0003] For example, Patent Document 1 discloses a cup container and a film that can release water vapor during microwave heating by providing a break portion having an unoriented portion disposed opposite to each other with an oriented portion of a crystalline stretched and oriented film interposed therebetween on a lid.

[0004] Also, for example, Patent Document 2 discloses a film that can form a through hole for releasing water vapor when heated in a microwave oven by forming a weak processing line.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the above-described technology, when using a container having a bottom portion, a body portion, and a square flange portion, if the internal pressure increases due to water vapor generated during microwave heating, there is a risk that a beak-like deformation that protrudes upward may occur in the flange portion. And when deformation occurs in the flange portion, the rupture portion formed in the lid may not rupture. For this reason, a technology capable of suppressing deformation of the flange portion when the internal pressure of the container increases is required.

[0007] Therefore, an object of the present invention is to provide a container and a container with contents that can suppress deformation of the flange portion even when the internal pressure increases during microwave heating.

Means for Solving the Problems

[0008] According to one aspect of the present invention, a container is a container to which a lid having a rupture portion that ruptures due to an increase in internal pressure is sealed, and includes a body portion having at least a side extending in one direction, a bottom portion provided at a lower end of the body portion, a flange portion provided at an upper end of the body portion to which the lid is heat-sealed, and a flange having a skirt portion extending downward from an outer edge of the flange portion.

[0009] According to one aspect of the present invention, a container with contents includes the above-described container, the lid heat-sealed to the flange portion of the container, and the contents accommodated in the container.

Effects of the Invention

[0010] According to the present invention, it is possible to provide a container and a container with contents that can suppress deformation of the flange portion even when the internal pressure increases during microwave heating.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0012] Hereinafter, the structure of the container 1 containing the content according to the embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. 1 is a plan view showing the structure of the container 1 containing the content according to the embodiment of the present invention with a part of the lid 12 omitted. FIG. 2 is a plan view showing the structure of the container 11 used for the container 1 containing the content. FIG. 3 is a cross-sectional view showing the structure of the container 11 along the line III-III in FIG. 2, and FIG. 4 is a cross-sectional view showing the structure of the container 11 along the line IV-IV in FIG. 2. FIG. 5 is an explanatory drawing showing the structure of the skirt portion 23b formed on the flange 23 of the container 11.

[0013] As shown in FIG. 1, the container 1 containing the content includes a container 11, a lid 12 for sealing the container 11, and a content 100 accommodated in the container 11. The container 1 containing the content is a packaging container for microwave heating in which the content is heated by a microwave oven with the container 11 sealed by the lid 12. Here, the content 100 contains moisture that is heated by a microwave oven, and includes, for example, foods cooked by heating in a microwave oven and articles such as towels heated by a microwave oven.

[0014] As shown in FIGS. 1 to 4, the container 11 is a bottomed container capable of accommodating the content 100. The container 11 is a cup-shaped, dish-shaped, tray-shaped or the like container having a straight portion with at least one side extending in one direction. The container 11 is, for example, polygonal. In the example of the present embodiment, the container 11 is, for example, a rectangular container that is long in one direction. That is, the container 11 is, for example, rectangular and long in one direction, and a pair of long sides and a pair of short sides extend in a direction perpendicular to each other. Note that the corners continuous with the long sides and the short sides of the container 11 may be inclined with respect to the long sides and the short sides. The container 11 includes a body portion 21, a bottom portion 22, and a flange 23. The container 11 is formed of, for example, a resin material, and specifically, polypropylene (PP) or polystyrene (PS). The container 11 is formed by vacuum forming or pressure air forming. The container 11 has, for example, an area of a region defined by the outer peripheral edge of the flange portion 23a of 50 cm 2 or more and 900 cm 2 or less.

[0015] The lower end of the body portion 21 is closed by the bottom portion 22, and the upper end where the flange 23 is integrally formed is open. The body portion 21 is, for example, rectangular and long in one direction, and a pair of long sides and a pair of short sides extend in a direction perpendicular to each other. Also, for example, the corners continuous with the long sides and the short sides of the body portion 21 may be inclined with respect to the long sides and the short sides. The body portion 21 includes, for example, a first side portion 21a that is integrally continuous with the bottom portion 22 and gradually decreases in width from the flange 23 side toward the bottom portion 22, and a second side portion 21b that connects the upper end of the first side portion 21a and the flange 23. The body portion 21 also includes reinforcing ribs 21e provided in plurality at the upper end of the first side portion 21a.

[0016] The first side portion 21a is formed in a tapered shape that is inclined with respect to the axial direction of the body portion 21 such that the width gradually decreases from the flange 23 side toward the bottom portion 22 side. The second side portion 21b is set to a width larger than the width of the upper end of the first side portion 21a.

[0017] When stacking the containers 11, the reinforcing ribs 21e overlap vertically, and the reinforcing ribs 21e of the containers 11 that overlap vertically engage with each other, so that the containers 11 that overlap vertically are in a predetermined arrangement relationship. For example, the reinforcing rib 21e is formed at the upper end of the first side portion 21a. For example, a plurality of reinforcing ribs 21e are formed on at least a pair of long sides of the body portion 21, that is, a pair of surfaces on the long side side, of the first side portion 21a. In the example of FIG. 2, a plurality of reinforcing ribs 21e are arranged on the entire surface of the first side portion 21a. For example, the reinforcing rib 21e is a rectangular protrusion protruding outward from the body portion 21. For example, the reinforcing rib 21e is formed in a shape that creates a gap of 0.5 mm or more in the axial direction between the lower end of the skirt portion 23b of the upper container 11 and the upper surface of the flange portion 23a of the lower container 11 among the stacked adjacent containers 11. Note that the gap between the lower end of the skirt portion 23b of the upper container 11 and the upper surface of the flange portion 23a of the lower container 11 among the stacked adjacent containers 11 can be set to an arbitrary gap by adjusting the dimension in the height direction of the reinforcing rib 21e.

[0018] In addition to the function of defining the positional relationship between adjacent containers 11 during stacking, the reinforcing rib 21e may constitute a reinforcing structure for improving the strength of the body portion 21. For example, in order for the reinforcing rib 21e to exhibit the function of improving the strength of the body portion 21, the arrangement, number, and shape can be appropriately selected according to the shape of the container 11 in order to suppress deformation of the container 11. In particular, in order to suppress deformation of the container 11, it is preferable to form the reinforcing rib 21e in a range within 30% of the side length from the center of the side extending in one direction of the body portion 21.

[0019] The bottom portion 22 is integrally formed at the lower end of the body portion 21. The bottom portion 22 is formed in a flat plate shape. For example, the central side may protrude toward the flange 23 side more than the outer edge side.

[0020] The flange 23 is integrally formed, for example, at the upper end (open end) of the body portion 21. The flange 23 is formed in an annular shape that extends in a direction orthogonal or intersecting to the axial direction of the body portion 21 along the outer peripheral shape of the upper end edge of the body portion 21. For example, the flange 23 is in a rectangular shape that is long in one direction, and a pair of long sides and a pair of short sides extend in a direction perpendicular to each other. Also, for example, the flange 23 has corners continuous with the long sides and short sides that are inclined with respect to the long sides and short sides. The flange 23 includes a flat flange portion 23a, a skirt portion 23b that extends downward from the outer edge of the flange portion 23a, and a hem portion 23c that extends outward from the lower end of the skirt portion 23b.

[0021] The flange portion 23a is formed, for example, in an annular flat shape that extends along the outer peripheral shape of the body portion 21. For example, the flange portion 23a is formed such that the width in a direction orthogonal to the extending direction is substantially constant, and is in a rectangular shape that is long in one direction. For example, the corners continuous with the long sides and short sides are inclined with respect to the long sides and short sides. The lid 12 is heat-sealed to the upper surface of the flange portion 23a. As a specific example, a heat-sealing jig is disposed on the lower surface of the flange portion 23a, and the lid 12 is heated while being pressed against the upper surface of the flange portion 23a, so that the lid 12 is heat-sealed to the flange portion 23a. The flange portion 23a is formed, for example, to be slightly inclined such that the outer edge side is downward with respect to the vertical direction or with respect to a direction orthogonal to the vertical direction. The flange portion 23a is formed in an annular flat shape.

[0022] The skirt portion 23b is formed in an annular shape and extends downward from the outer edge of the flange portion 23a. The length of the skirt portion 23b is preferably 3 mm or more and 15 mm or less. Note that the length of the skirt portion 23b is more preferably 4 mm or more and 9 mm or less. Here, the length of the skirt portion 23b is, as shown by "A" in FIG. 5, the length along the outer surface that extends downward of the skirt portion 23b from the ridge portion between the flange portion 23a and the skirt portion 23b to the ridge portion between the skirt portion 23b and the hem portion 23c. Also, the length A of the skirt portion 23b may be, for example, different lengths on the long side and short side. For example, the length of the skirt portion 23b on the long side is longer than the length of the skirt portion 23b on the short side.

[0023] The skirt portion 23c is formed in a ring shape and extends outward from the lower end of the skirt portion 23b. For example, the skirt portion 23c extends outward along a direction orthogonal to the axial direction of the container 11 from the lower end of the skirt portion 23b. The length of the skirt portion 23c is preferably 1.5 mm or more and 10 mm or less. More preferably, the length of the skirt portion 23c is 2.0 mm or more and 5.0 mm or less. Here, the length of the skirt portion 23c is, as shown by "B" in FIG. 5, the length of the upper surface along the extending direction of the skirt portion 23c from the ridge portion between the skirt portion 23b and the skirt portion 23c to the end portion of the skirt portion 23c. For example, the skirt portion 23c is formed when the container 11 is trimmed from the sheet material of the resin material, which is the molding material, during the molding of the container 11.

[0024] Also, for example, the angle between the flange portion 23a and the skirt portion 23b is set to 90 degrees or more. Here, the angle between the flange portion 23a and the skirt portion 23b is, as shown by "C" in FIG. 5, the angle between the lower surface of the flange portion 23a and the inner surface of the skirt portion 23b. The angle C is, for example, 90 degrees or more and 120 degrees or less in order to improve the strength of the flange 23. Also, for example, the angle between the skirt portion 23b and the skirt portion 23c is set to 120 degrees or less. Here, the angle between the skirt portion 23b and the skirt portion 23c is, as shown by "D" in FIG. 5, the angle between the outer surface of the skirt portion 23b and the upper surface of the skirt portion 23c. The angle D is, for example, 60 degrees or more and 120 degrees or less in order to improve the strength of the flange 23.

[0025] Since the body portion 21 of the container 11 configured in this way becomes narrower downward, a plurality of them can be formed so as to be stackable. Also, in a plurality of containers 11, the reinforcing ribs 21e of adjacent containers 11 in contact with each other during stacking. For adjacent stacked containers 11, for example, a gap of 3 mm or more is formed in the axial direction between the lower end of the skirt portion 23b of the upper container 11 and the upper surface of the flange portion 23a of the lower container 11.

[0026] The lid 12 is, for example, a film having a resin layer capable of heat-sealing to the flange portion 23a. The lid 12 has a breaking portion 12a that breaks when the internal pressure of the heat-sealed container 11 rises and reaches a predetermined internal pressure or higher. The breaking portion 12a is formed in a part of the lid 12 and is configured to be able to form a steam outlet through which steam escapes by breaking due to the increase in internal pressure. Various techniques can be applied to the breaking portion 12a. That is, the breaking portion 12a formed in the lid 12 may have, for example, a plurality of sites where the orientation is relaxed, and a steam outlet may be formed between these sites where the orientation is relaxed, as long as it is configured to be able to break due to the increase in internal pressure. Also, it may be formed by reducing the strength of a part of the lid 12 so that it breaks earlier than other parts of the lid 12 when the internal pressure rises to form a steam outlet. For example, the breaking portion 12a is provided on the central side of the lid 12. Note that the arrangement of the breaking portion 12a can be set as appropriate as long as it is configured to break due to the increase in internal pressure.

[0027] The container 1 with the contents configured as such is designed such that when the contents 100 are heated by a microwave oven, the internal pressure of the container rises, causing the lid 12 to expand in a dome shape. When the internal pressure of the container reaches a predetermined internal pressure, the breaking portion 12a of the lid 12 breaks to release the internal pressure of the container. In this container 1 with the contents, by providing a skirt portion 23b on the flange 23 of the container 11, the strength of the flange 23 can be improved. Therefore, when the contents 100 are heated by a microwave oven and the lid 12 expands in a dome shape, deformation of the flange 23 due to the stress during deformation of the lid 12 is suppressed. That is, in the present invention, when the lid 12 expands upon an increase in the internal pressure of the container, the center of the long side, which is a side extending in one direction of the flange 23, is pulled by the lid 12 and deformed into a beak shape so as to protrude upward, and there is a risk that the flange 23 will be plastically deformed into a shape not assumed. Further, when the flange 23 is deformed so as to protrude upward, the stress applied to the lid 12 by the internal pressure of the container is relaxed, and the breaking portion 12a may not break at the predetermined internal pressure. However, the container 11 of the present embodiment can improve the strength of the flange 23 by the skirt portion 23b extending downward from the flange portion 23a so as to resist deformation of the flange 23 being pulled upward along with the deformation of the lid 12 when the internal pressure of the container rises. Therefore, deformation of the flange portion 23a can be suppressed, and the breaking portion 12a of the lid 12 can break at the predetermined internal pressure.

[0028] Further, the flange 23 can improve the strength of the skirt portion 23b by providing a hem portion 23c extending outward from the lower end of the skirt portion 23b. Therefore, deformation of the flange portion 23a by the skirt portion 23b can be further suppressed.

[0029] Also, the container 11 can improve the strength of the body portion 21 by providing a reinforcing rib 21e on the body portion 21. Therefore, when a force is applied to the container 11 in the direction in which the flange portion 23a deforms, the body portion 21 suppresses deformation of the flange portion 23a. Thus, the container 11 can suppress deformation of the flange portion 23a by providing the reinforcing rib 21e in addition to the skirt portion 23b.

[0030] Further, since the container 11 has the reinforcing rib 21e, when a plurality of containers 11 are stacked, the reinforcing rib 21e creates a gap between the lower end of the skirt portion 23b of the upper container 11 and the upper surface of the flange portion 23a of the lower container 11. Therefore, since engagement between the stacked containers 11 can be suppressed, the stacked containers 11 can be easily separated when the container 11 is filled with the content 100 or the like. Thus, the container 11 can improve the manufacturing efficiency of the container 1 with the content.

[0031] Also, when the container 11 is formed in a rectangular shape having a short side and a long side, the strength is lower on the long side than on the short side. For this reason, when the internal pressure rises, the container 11 is more likely to have a beak-shaped deformation of the flange 23 on the long side than on the short side. However, the container 11 can improve the strength of the long side, for example, by making the length of the skirt portion 23b longer on the long side than on the short side. Thus, the deformation of the flange 23 on the long side can be effectively suppressed, and the material cost can be reduced.

[0032] Next, an evaluation test of the container 11 configured as described above will be described with reference to FIGS. 6 to 8. The evaluation test is for clarifying the characteristics of the container 11 of the present embodiment, and the scope of the present invention is not limited to the following examples.

[0033] [Evaluation Test] As the evaluation test, the containers 11 of Examples 1 to 3 and the containers of Comparative Example 1 and Comparative Example 2 below were prepared, and 150 g of water was put into each of the containers 11 of Examples 1 to 3 and the container trays of Comparative Example 1 and Comparative Example 2, and the lid 12 was heat-sealed to create five samples each. Then, each sample using the containers 11 of Examples 1 to 3 and the containers of Comparative Example 1 and Comparative Example 2 was heated up to 1600 W for 60 seconds, the lid 12 was removed, and as shown in FIG. 6, at each of the four locations of the pair of long sides (1), (2) and the pair of short sides (3), (4) of the flange portion 23a, the amount of deformation at the location where the deformation of the flange portion 23a was the largest was read.

[0034] For the container 11 of Example 1, the length of the skirt portion 23b was 4.11 mm; for the container 11 of Example 2, the length of the skirt portion 23b was 6.11 m; and for the container 11 of Example 3, the length of the skirt portion 23b was 8.11 mm. Also, for the material of the containers 11 of Examples 1 to 3, non-colored PP was used.

[0035] For the containers 11 of Comparative Example 1 and Comparative Example 2, the length of the skirt portion 23b was 1.61 mm. Also, for the material of the container of Comparative Example 1, black-colored PP was used, and for the material of the container of Comparative Example 2, non-colored PP was used.

[0036] Also, the lids 12 heat-sealed to the containers 11 of Examples 1 to 3 and the containers of Comparative Example 1 and Comparative Example 2 were PET(12) / PBT(15) / easy peel(30), and the rupture portion 12a was configured such that four holes were formed as steam vents due to an increase in internal pressure.

[0037] Also, as a method for reading the amount of deformation of the flange portion 23a, with the state of no deformation before heating as a reference, the distance from the reference to the top of the beak-shaped deformed flange portion 23a after heating was read by applying a scale as shown in FIG. 6, and this distance was taken as the amount of deformation. Then, as shown in FIG. 7, when there was no beak-shaped deformation (amount of deformation = 0 mm: no deformation), the evaluation was ◎; when the amount of deformation of the beak-shaped deformed flange portion 23a was 3 mm or less, the evaluation was ○ (small deformation); when the amount of deformation of the beak-shaped deformed flange portion 23a was 5 mm or less, the evaluation was △ (medium deformation); and when the amount of deformation of the beak-shaped deformed flange portion 23a exceeded 5 mm, the evaluation was × (large deformation) for determination. [Results of the evaluation test] The results of the evaluation test are shown in FIG. 8. As shown in FIG. 8, in both Comparative Example 1 and Comparative Example 2, in all five samples, the amount of deformation in both (1) and (2) in the long side direction of the flange portion 23a exceeded 5 mm. Also, in (3) and (4) in the short side direction of the flange portion 23a, beak-shaped deformation was observed.

[0038] On the other hand, in the samples of the container 11 of Examples 1 to 3, the deformation amounts in both (1) and (2) in the long side direction of the flange portion 23a were 5 mm or less. Further, in the containers 11 of Examples 2 and 3, there was no deformation or the deformation amount was 3 mm or less. Further, in all the samples of the container 11 of Examples 1 to 3, no deformation was observed in (3) and (4) in the short side direction of the flange portion 23a.

[0039] From the results of such evaluation tests as well, it became clear that by providing the skirt portion 23b on the flange 23 of the container 11, it is possible to prevent deformation of the flange 23 (flange portion 23a) or suppress the deformation of the flange 23 and reduce the deformation amount even when the contents 100 are heated by a microwave oven.

[0040] As described above, according to the container 11 and the container 1 containing the contents according to the embodiment, even when the internal pressure rises during microwave heating, deformation of the flange portion 23a can be suppressed.

[0041] Note that the present invention is not limited to the above-described embodiment. For example, in the above-described example, the container 11 was described as an example of a rectangular container that is long in one direction, but it is not limited to this. That is, the container 11 may have a shape having a straight portion in which at least one side extends in one direction. For this reason, it may have an irregular shape, or a shape in which two opposing sides have straight portions, or a hexagonal or octagonal container.

[0042] Further, for example, in the above-described example, as an example of the configuration and method of fixing the lid 12 to the flange 23, an example of heat sealing was described, but it is not limited to this. For example, adhesion using an adhesive may be used, or other configurations and methods may be used. That is, the method and configuration for fixing the lid 12 to the flange 23 are not limited as long as the lid 12 does not come off from the flange 23 and the breaking portion 12a breaks when the container 1 containing the contents is heated.

[0043] Note that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist thereof at the implementation stage. Also, the respective embodiments may be implemented in appropriate combination, and in that case, the combined effects can be obtained. Furthermore, the above embodiments include various inventions, and various inventions can be extracted by combinations selected from a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiments, if the problem can be solved and the effects can be obtained, the configuration with these deleted constituent elements can be extracted as an invention.

Explanation of Reference Numerals

[0044] 1... Container with contents, 11... Container, 12... Lid, 12a... Breaking part, 21... Body part, 21a... First side part, 21b... Second side part, 21e... Reinforcing rib, 22... Bottom part, 23... Flange, 23a... Flange part, 23b... Skirt part, 23c... Hem part, 100... Contents.

Claims

1. A container in which a lid having a breaking portion that breaks due to an increase in internal pressure is sealed, comprising: a body portion having at least a side extending in one direction; a bottom portion provided at the lower end of the body portion; a flange provided at the upper end of the body portion, having a flange portion where the lid is sealed, and a skirt portion extending downward from the flange portion; A container comprising the above.

2. The container according to claim 1, wherein the length of the skirt portion is 3 mm or more and 15 mm or less.

3. The container according to claim 1, wherein the body portion and the flange portion are rectangular in shape and long in one direction, and a pair of long sides and a pair of short sides extend in a direction perpendicular to each other.

4. The container according to claim 3, wherein the body portion has a reinforcing structure on at least a pair of long sides.

5. The container according to claim 4, wherein the body portion has a plurality of reinforcing ribs protruding outward on at least a pair of long sides.

6. The container according to claim 5, wherein when a plurality of the containers are stacked, the reinforcing ribs form a predetermined interval in the axial direction between the lower end of the skirt portion and the upper surface of the flange portion.

7. The container according to claim 2, wherein the flange has a hem portion extending outward from the lower end of the skirt portion and having a length of 1.5 mm or more and 10 mm or less.

8. The container according to claim 3, wherein the skirt portion provided on the long side is longer than the skirt portion provided on the short side.

9. A container containing contents, comprising the container according to any one of claims 1 to 8, a lid heat-sealed to the flange portion of the container, and the contents accommodated in the container.

Images