paper container

Abstract

The present invention provides a paper container that allows the contents to be adequately heated in a microwave oven and facilitates a smooth process from heating to consumption. [Solution] The paper container 1 comprises a paper sleeve 10 formed in a cylindrical shape with two opposing sets of surfaces, a paper inner box 20 having an open top and being able to enter the sleeve, a bottom surface 25 to which a heating sheet configured to become hot when irradiated with microwaves is attached, and sides rising from the bottom surface. Of the two sets of surfaces, the distance between one set of surfaces, including the top surface 11 that covers the top of the inner box housed in the sleeve, is longer than the height of the sides, and when the inner box is housed in the sleeve, there is a gap between the inner box and the top surface.

Description

Technical Field

[0001] The present invention relates to a paper container, and more particularly to a paper container that can be suitably heated in a microwave oven while containing the contents.

Background Art

[0002] There is known a heat-generating sheet that becomes high temperature by irradiation with microwaves. Containers having such a heat-generating sheet disposed therein are also known (see, for example, Patent Document 1). By disposing the heat-generating sheet, when heated in a microwave oven, the interior becomes hotter than when relying solely on the heat generation of the contents themselves, enabling more suitable heating and cooking.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Although Patent Document 1 exemplifies several aspects of the container, the inventors have found that there is still room for improvement in view of the series of processes from heating to eating, and have completed the present invention.

[0005] An object of the present invention is to provide a paper container that can be suitably heated in a microwave oven and can smoothly perform operations from heating to eating.

Means for Solving the Problems

[0006] The present invention provides a paper container comprising a paper sleeve formed in a cylindrical shape having two pairs of opposing surfaces, a bottom surface to which a heat-generating sheet configured to become high temperature by irradiation with microwaves is attached, and side surfaces rising from the bottom surface, and having an upper opening and a paper inner box into which the sleeve can enter. In this paper container, of the two sets of surfaces of the sleeve, the distance between the set of surfaces including the top surface that covers the top of the inner box housed within the sleeve is longer than the height of the sides of the inner box, and when the inner box is housed within the sleeve, there is a gap between the inner box and the top surface. Paper container. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a paper container that can suitably heat its contents in a microwave oven and that allows for smooth operation from heating to consumption. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view showing a paper container according to one embodiment of the present invention. [Figure 2] This is a plan view showing the inner box of the paper container. [Figure 3] This figure shows the blanks related to the inner box. [Figure 4] This is a schematic cross-sectional view showing the layer structure of the heating sheet related to the paper container. [Figure 5] This is a view of the paper container from the opening side of the sleeve. [Figure 6] This figure shows the inner box in its unfolded state. [Modes for carrying out the invention]

[0009] One embodiment of the present invention will be described with reference to Figures 1 to 6. Figure 1 is a perspective view showing a paper container 1 according to this embodiment. As shown in Figure 1, the paper container 1 comprises a cylindrical sleeve 10 and an inner box 20 placed inside the sleeve 10.

[0010] The sleeve 10 in this embodiment is a rectangular tubular member having a rectangular parallelepiped shape with openings at two points on its sides. The sleeve 10 can be formed by folding and joining a single sheet of paper with glue or the like, but it may also be formed using two or more sheets of paper.

[0011] Figure 2 shows a plan view of the inner box 20 with the sleeve 10 removed. The inner box 20 has a main body 21 formed by folding a single sheet of paper, and a heating sheet 50 attached to the main body 21.

[0012] Figure 3 shows a blank 100, which is a paper sheet used to form the inner box 20. The inner box 20 has a rectangular bottom surface 25, a pair of first sides 30 connected to the long side of the bottom surface 25, and a pair of second sides 40 connected to the short side of the bottom surface 25.

[0013] On both longitudinal sides of each first side surface 30, there are locking pieces 31 that engage with the second side surface 40 in the completed inner box 20. A fold line 32 is formed at the boundary between the first side surface 30 and the locking piece 31 to assist in the folding operation when forming the inner box 20. The locking piece 31 has a step 33 at the upper edge in the completed inner box 20, and the first region 34, which is closer to the first side surface 30 than the step 33, is formed to be higher than the second region 35, which is further away from the first side surface 30 than the step 33.

[0014] Each second side surface 40 has a tongue piece 41 on the side not connected to the bottom surface 25 that engages with a locking piece 31. Notches 42 are provided at both ends of the boundary between the second side surface 40 and the tongue piece, which extends in the longitudinal direction of the second side surface 40. The notches 42 extend for a certain length along the boundary from both ends, then curve slightly toward the bottom surface 25 before ending. Furthermore, a fold line 43 is formed in a straight line connecting the two notches 42. The length of the fold line 43 is slightly longer than the distance between the first side surface 30 and the step 33 in the longitudinal direction of the first side surface 30.

[0015] Figure 4 is a schematic cross-sectional view of the heating sheet 50. As shown in Figure 4, the heating sheet 50 has a known configuration comprising a resin film 51, an aluminum layer 52 formed on the film 51, and a paper substrate 53 bonded to the aluminum layer 52, and the Susceptor® manufactured by TOPPAN Holdings is widely known. When the heating sheet 50 receives microwaves irradiated from a microwave oven, it reaches a high temperature of around 200°C.

[0016] An example of the manufacturing procedure of the paper container 1 will be described. Blanks 100 are formed by punching or the like using a blade, glue is applied to the bottom surface 25 using a plate or the like, and the heating sheet 50 is joined. The joining of the heating sheet 50 may be performed before punching.

[0017] Next, the two first side surfaces 30 in contact with the bottom surface 25 are bent and raised substantially perpendicular to the bottom surface 25, and each locking piece 31 is further bent so as to form a substantially right angle with the first side surface 30. Subsequently, the two second side surfaces 40 are bent and raised substantially perpendicular to the bottom surface 25, and the tongue piece 41 is further bent so as to form a substantially right angle with the second side surface 40. Then, as shown in FIG. 2, the upper part of the first region 34 of the locking piece 31 enters into the notch 42 and protrudes slightly higher than the bent tongue piece 41. Thereby, the engagement state between the first side surface 30 and the second side surface 40 is maintained, and the middle box 20 with the upper side open is completed.

[0018] Subsequently, the middle box 20 is inserted into the sleeve 10 prepared separately. The opening of the sleeve 10 has dimensions corresponding to the second side surface 40, and since the middle box 20 is slightly lower than the sleeve 10, the middle box 20 can be made to enter the sleeve 10 by facing one of the second side surfaces 40 toward the opening of the sleeve 10.

[0019] Thus, the paper container 1 according to the present embodiment is completed. In the completed paper container 1, among the four surfaces of the sleeve 10, the top surface 11 covers the open upper part of the middle box 20, and the bottom surface 12 is arranged to overlap with the bottom surface 25. Furthermore, the height of the pair of side surfaces 13 connecting the top surface 11 and the bottom surface 12 (i.e., roughly the same as the distance between the top surface 11 and the bottom surface 12) is slightly higher than the first side surface 30 and the second side surface 40 of the inner box 20. As shown in Figure 5, a small gap of about 1 mm in the height direction is created between the top surface 11 and the inner box 20. From the viewpoint of preventing unintended opening during heating or unintended sliding of the inner box during transport, this gap is preferably 3 mm or less.

[0020] When food is placed inside the inner box 20 and the paper container 1 is placed in a microwave oven for heating, microwaves emitted from the microwave oven penetrate each surface of the paper container 1 and reach the heating sheet 50. As a result, the heating sheet 50 becomes hot, allowing the food to be heated or cooked at a temperature higher than the food's own heat generation. At this time, since the upper opening of the inner box 20 is covered by the top surface 11 of the sleeve 10, the steam generated by heating is appropriately retained inside the paper container 1, allowing the food to steam properly. On the other hand, excess steam is smoothly released through the gap between the sleeve 10 and the inner box, effectively preventing the paper container 1 from bursting or being damaged during heating. The paper container 1 may be placed on a plate and put into the microwave. Alternatively, before putting it in the microwave, the inner box 20 may be pulled out of the sleeve 10 and the food may be rearranged to ensure proper heating and prevent food from sticking together.

[0021] Once heating is complete, the user removes the paper container 1 from the microwave. When consuming food, the inner box 20 can be pushed and pulled against the sleeve 10, allowing for easy and smooth removal of the sleeve 10 without touching the hot bottom surface. The user may eat the heated food directly from the inner box 20 or transfer it to another dish. In either case, the entire process from heating to consumption can be carried out smoothly.

[0022] When transferring heated food to another dish, the inner box 20 is formed by the mechanical engagement of the first side 30 and the second side without the use of glue or adhesive. By lifting the tab 41 on the second side 40 and releasing the engagement between the first side 30 and the second side 40, as shown in Figure 6, the second side 40 can be tilted. In this way, the food can be easily slid along the tilted second side 40 to transfer it to another dish. Figure 6 shows both second sides 40 tilted, but when transferring to a dish, it is sufficient to tilt only one side; it is not necessary to tilt both.

[0023] As described above, the paper container 1 according to this embodiment allows for convenient and easy heating of the food or other items contained within it, including steaming, by using a microwave oven. Furthermore, unlike hinged lids and the like, the sleeve 10 covering the upper opening of the inner box 20 does not pose a risk of unintentionally opening during heating, thus enabling stable heating with steaming.

[0024] In the paper container 1, the heating sheet 50 placed on the bottom surface 25 causes the bottom surface to become significantly hotter than that of food heated in a regular microwave after heating in a microwave oven. However, in the paper container, the bottom surface 12 of the sleeve 10 is located below the bottom surface 25, resulting in a state where two layers of paper are stacked. As a result, even if the user accidentally touches the bottom of the container, the high temperature is less likely to directly affect the user's hands or fingers. In addition, in the structure according to this embodiment, in which the inner box 20 is inserted through the sleeve 10, opening the box after heating and transferring the contents to a dish can be done by holding the side surface 13 of the sleeve 10 and pressing the second side surface 40, thereby reducing the possibility of touching the bottom surface 25.

[0025] Although one embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and modifications and combinations of the configuration that do not depart from the spirit of the present invention are also included.

[0026] For example, in the sleeve according to the present invention, due to the structure described above, at least one of the four surfaces is joined together to form a cylindrical shape, resulting in a double layer. However, by making the bottom surface a double layer, the lower part of the paper container on which the heating sheet 50, which becomes hot after cooking, is placed can be made a triple layer when combined with the bottom surface 25 of the inner box 20, resulting in a safer configuration.

[0027] Furthermore, the dimensions of the inner box in the direction of entry into the sleeve may be shorter than those of the sleeve. This allows the entire inner box to be positioned inside the sleeve, preventing the engagement between the first and second sides from unintentionally disengaging during heating. This effect can also be achieved by configuring the inner box so that the second side is parallel to the side surface of the sleeve. In this case, even if a part of the inner box is located outside the sleeve, the engagement between the first and second sides can be prevented from disengaging.

[0028] To further optimize the steaming process, the top surface of the sleeve may be curved upwards. In the paper container according to this embodiment, even in this embodiment, a gap is maintained near the side where the top surface and the inner box are closest.

[0029] Furthermore, the arrangement of the heating sheets is not limited to those described above. For example, by arranging multiple strip-shaped heating sheets at intervals on the bottom surface and placing a relatively large contents in the inner box, it is possible to create multiple linear or strip-shaped brown marks on the contents after heating.

[0030] There are no particular restrictions on the paper material used for the paper containers of the present invention, but virgin paper is preferred when storing food. Suitable examples include Pearl Card and Mitsubishi Water-Resistant paper manufactured by Mitsubishi Paper Mills, and Ultra H paper manufactured by Nippon Paper Industries. The basis weight of the paper should be 310g to 350g / m². 2 This degree is desirable, and using paper of this basis weight can increase the versatility of paper containers. [Explanation of Symbols]

[0031] 1. Paper container 10 sleeves 11 Top surface 20 medium boxes 25 Bottom 30 First aspect 40 Second aspect 50 Heat-generating sheets

Claims

1. A paper sleeve formed in a cylindrical shape with two opposing sets of surfaces, A paper inner box having a bottom surface to which a heating sheet configured to become hot when irradiated with microwaves is attached, and sides rising from the bottom surface, with the top open and capable of entering the sleeve, Equipped with, Of the two sets of surfaces, the distance between the two sets of surfaces, including the top surface that covers the upper part of the inner box housed in the sleeve, is longer than the height of the side surface. When the inner box is housed within the sleeve, there is a gap between the inner box and the top surface. Paper container.

2. The gap is 1 millimeter or more. The paper container according to claim 1.

3. The aforementioned inner box is The base is square, The base has a first side surface rising from two opposing sides of the four sides, and a second side surface rising from the remaining two sides. The first side surface and the second side surface, which rise from the bottom surface, are formed by mechanically engaging with each other. The paper container according to claim 1.

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