JP6540139B2 - Container with lid - Google Patents

Description

  The present invention relates to a lidded container including a container in which a container is formed and a lid joined to the container so as to seal the container of the container.

  Conventionally, many contents such as cooked or semi-cooked food are stored in a plastic container such as a tray and sealed with a lid made of a film or the like in large numbers on the market. The contents are heated by a microwave oven or the like in a state of being accommodated in a plastic container.

  By the way, when the contents contained in the container sealed by the lid are heated using a microwave oven, the water contained in the contents evaporates along with the heating, and the pressure in the container of the container is increased. Go. If the pressure in the container of the container is increased, the lid or the container may be ruptured and the contents may be scattered to contaminate the inside of the microwave oven. In consideration of such problems, it has been proposed to provide a steam removal function for communicating the storage portion with the outside to release the steam in the storage portion to the outside when the pressure in the storage portion of the pouch reaches a predetermined value or more.

  For example, in patent documents 1-3, forming a projection line which protrudes inside a container is proposed in a part of strip shaped heat seal line which welds a lid and a flange of a container by heat welding. In this case, the pressure in the container of the container is increased with heating, and when the lid is partially expanded above the flange of the container, the protruding line is first peeled off from the lid or the flange. As a result, a steam hole is formed between the lid and the flange portion of the container, where steam is released to the outside, at the location where the projecting line is provided. As described above, by providing a part of the heat seal line that is more susceptible to peeling than other parts, it is possible to stably release the steam to the outside at the targeted part.

Tokuhei 8-25583 Unexamined-Japanese-Patent No. 9-221177 gazette Patent No. 4665538 gazette

  In the containers described in Patent Documents 1 to 3, the flange portion of the container has a substantially square contour. In this case, if the expansion of the lid during heating of the contents using the microwave oven varies, the peeling force to peel the lid from the container based on the expansion of the lid is the heat seal line other than the protruding line. It is thought that there is a part that works in the beginning. In this case, it is conceivable that the portion other than the protruding line is peeled off from the lid or the flange portion earlier than the protruding line, whereby the steam escapes from the unintended location to the outside. It is also conceivable that the lid may rupture before the protruding lines are peeled off.

  An object of the present invention is to provide a lidded container which can effectively solve such problems.

  The present invention comprises a container in which a container is formed, and a lid joined to the container so as to seal the container of the container, the container having a bottom surface and an outer edge of the bottom surface. The container has a side surface erected from the bottom surface so as to extend over the entire circumference, and a flange portion connected to an upper portion of the side surface and joined to the lid, and the contour of the flange portion of the container is a pair of lengths A bonding line including a side and a pair of short sides and connecting the lid and the flange portion is continuously formed over the entire circumference between the lid and the flange portion of the container. The container has a main line extending along an outer edge of the flange and a protruding line disposed on the long side of the flange and protruding inward from the main line, the container Said junction line from the center point of Assuming that the shortest distance to the outer edge of the protruding line is D1, and the shortest distance from the center point of the container to the inner edge of the main line on the short side of the flange portion is D2, the ratio of D2 to D1 is 1 It is a container with a lid which is .50 or more.

  In the lidded container according to the present invention, the projecting lines of the joining line may be respectively disposed on the pair of long sides of the flange portion.

  In the lidded container according to the present invention, the projecting line of the joining line includes a pair of first portions extending inward from the main line, and a second portion connecting the pair of first portions. The second portion may have a curved shape that is convex inward.

  In the lidded container according to the present invention, the flange portion has a protrusion formed on the long side so as to protrude inward, and the protrusion line of the joint line is formed on the protrusion of the flange portion. It may be arranged in

  In the lidded container according to the present invention, the projecting portions may be respectively formed on the pair of long sides of the flange portion.

  In the lidded container according to the present invention, the width of the protrusion of the flange may be in the range of 10 to 15 mm.

  In the lidded container according to the present invention, the shortest distance from the outer edge of the projecting portion of the flange portion to the outer edge of the projecting line of the joining line may be in the range of 5 to 10 mm.

  The flange portion of the container according to the present invention has a rectangular outline including a pair of long sides and a pair of short sides. Moreover, between the lid and the flange portion of the container, a bonding line for bonding the lid and the flange portion is continuously formed over the entire circumference. The joint line has a main line extending along the outer edge of the flange and a protruding line disposed on the long side of the flange and protruding inward from the main line. When the shortest distance from the center point of the container to the outer edge of the protruding line of the joining line is D1, and the shortest distance from the center point of the container to the inner edge of the main line on the short side of the flange is D2, The ratio of D2 is 1.50 or more. Therefore, when the contents are heated, the protruding line can be easily separated from the flange portion earlier than the portion other than the protruding line. Thus, the steam holes can be stably formed where the projecting lines are provided. This can improve the usability of the lidded container.

FIG. 1 is a perspective view showing an example of a container according to an embodiment of the present invention. FIG. 2 is a plan view showing an example of a lidded container according to the embodiment of the present invention. FIG. 3 is a cross-sectional view showing the lidded container shown in FIG. 2 as viewed along the line III-III. FIG. 4 is an enlarged plan view showing a protruding line of a bonding line of the lidded container shown in FIG. 2; FIG. 5 is a view for explaining the shapes of the protruding line of the joining line and the protruding portion of the flange portion. FIG. 6 is a plan view showing how a bulge is formed on the lid by heating the contents. FIG. 7A is a plan view showing a state in which the bulge of the lid has reached the outer edge of the second portion of the projecting line of the joining line. 7B is a cross-sectional view showing the lidded container shown in FIG. 7A as viewed along the line VIIB-VIIB. FIG. 8A is a plan view showing how a recess is formed in the lid when the contents cool. FIG. 8B is a cross-sectional view showing the lidded container shown in FIG. 8A taken along line VIIIB-VIIIB. FIG. 9 is a plan view showing another example of the lidded container according to the embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 8A. First, the outline of the lidded container 10 according to the present embodiment will be described with reference to FIGS. 2 and 3. FIG. 2 is a plan view showing the lidded container 10 in the present embodiment, and FIG. 3 is a cross-sectional view showing the lidded container 10 shown in FIG. 2 as viewed along the line III-III.

(Container with lid)
As shown in FIGS. 2 and 3, the lidded container 10 includes a container 20 in which the storage portion 28 is formed, and a lid 50 joined to the container 20 so as to seal the storage portion 28 of the container 20. ing. In the present specification, "joining" is a concept including both welding and adhesion. By "welding" is meant attaching lid 50 to container 20 by at least partially melting container 20 or lid 50 at least partially. “Adhesive” also refers to attaching the lid 50 to the container 20 using components separate from the container 20 and the lid 50, such as an adhesive.

  Although the contents to be accommodated in the container 20 are not particularly limited, examples of the contents include retort foods, frozen foods, refrigerated foods and the like. Moreover, as food, curry, chopsticks, yakisoba, sugar beet, fish etc. can be mentioned. In these contents, since the water evaporates with heating and the pressure in the storage portion 28 of the container 20 increases, a vapor removal function for releasing the vapor in the storage portion 28 to the outside is required for the lidded container 10.

(container)
Next, the container 20 will be described with reference to FIGS. 1 to 3. FIG. 1 is a perspective view showing a container 20 of the lidded container 10 of FIG. The container 20 has a bottom surface 21, a side surface 23 erected from the bottom surface 21 so as to extend over the circumference of the bottom surface 21, and a flange portion 25 connected to the top of the side surface 23 and having a flat top surface. Have. The lid 50 described above is joined to the upper surface of the flange portion 25 of the container 20. FIGS. 1 and 2 show an example in which the flange portion 25 is provided continuously with the upper edge of the side surface 23 and extends horizontally outward. In the present specification, terms such as “side surface”, “upper portion”, “upper edge”, “upper surface”, “lower surface” and “horizontal direction” have lids so that the bottom surface 21 of the container 20 is positioned downward. The positions and directions of the lidded container 10, the container 20, the lid 50 and their constituent elements are indicated on the basis of the state in which the container 10 and the container 20 are placed.

  In the present embodiment, the contour of the flange portion 25 includes a pair of long sides 25 a and a pair of short sides 25 b. For example, as shown in FIGS. 1 and 2, the flange portion 25 has a substantially rectangular outline including a pair of long sides 25a and a pair of short sides 25b. In FIG. 2, reference symbol L1 represents the length of the long side 25a, reference symbol L2 represents the length of the short side 25b, and the length L1 is greater than the length L2. In FIG. 1 and FIG. 2, the code | symbol 25c represents the corner located between the long side 25a and the short side 25b. As shown in FIGS. 1 and 2, the corner 25c may have a curved shape. Such a corner 25c can be obtained, for example, by chamfering the corner of a flange having a rectangular contour. Although not shown, the corner 25 c may have an angular shape.

  As described later, as a method of manufacturing the container 20, injection molding using a thermoplastic resin such as polypropylene may be employed. When manufacturing the container 20 by injection molding, it is preferable to make height H of the container 20 below length L 2 of the short side 25b of the flange part 25 of the container 20, in order to ensure moldability.

  As will be described later, in the present embodiment, a protruding line disposed on a portion of the bonding line where the steam hole is to be formed is formed on the long side 25a. The length L1 of the long side 25a and the length L2 of the short side 25b are on the long side 25a even if there is a variation in the expansion of the lid 50 when heating the contents using a microwave oven Is set so that the protruding line of the cover peels from the lid 50 or the flange 25 before the other part of the joining line. For example, the ratio of D2 to D1 described later is set to be within a desired range.

  Although FIG. 2 shows an example in which the pair of long sides 25a are parallel to each other, the pair of short sides 25b are parallel to each other, and the long side 25a and the short side 25b are orthogonal to each other. There is no limitation to this. The directions of the long side 25a and the short side 25b can be set variously as long as a protruding line 34 described later disposed on the long side 25a can be peeled off earlier than the main line 32 on the short side 25b. . For example, the pair of long sides 25a may be nonparallel to each other, and the pair of short sides 25b may be nonparallel to each other. Further, the angle formed by the long side 25a and the short side 25b may be deviated from 90 degrees.

  Although FIG. 2 shows an example in which the outer edge 25y of the flange portion 25 linearly extends from one corner 25c to the other corner 25c, the present invention is not limited to this. Although not shown, a recess or the like may be partially formed in the outer edge 25y of the flange portion 25. That is, in the present specification, the form expressed by the phrase "the outline of the flange portion 25 includes a pair of long sides 25a and a pair of short sides 25b" corresponds to the outer edge 25y of the flange portion 25 from one corner 25c to the other There is no limitation to the form extending linearly to the corner 25c of the. The flange portion 25 may have an outline including a pair of long sides 25 a and a pair of short sides 25 b when the shape of the flange portion 25 is schematically viewed.

  As shown in FIGS. 1 and 2, the flange portion 25 has a protrusion 26 formed on the long side 25 a so as to protrude inward. In the present specification, the “inner side” means the side closer to the housing portion 28 of the container 20 in the horizontal direction. Further, “outside” means the side far from the storage portion 28 of the container 20 in the horizontal direction.

  In FIG. 1 and FIG. 2, the example in which the protrusion part 26 is respectively formed in a pair of long side 25a of the flange part 25 is shown. However, the present invention is not limited to this, and although not shown, the protrusion 26 may be formed on only one of the pair of long sides 25 a of the flange 25. In addition, in order to form a steam hole stably in the place where the protrusion line 34 mentioned later is formed, the protrusion part 26 is formed in a pair of long side 25a of the flange part 25, respectively, and a pair of protrusion part 26 top. Preferably, the projecting lines 34 are arranged at each of the two.

(Joining line)
As shown in FIGS. 2 and 3, a joint line 30 for joining the lid 50 and the flange 25 is continuously formed over the entire circumference between the lid 50 and the flange 25 of the container 20. The bonding line 30 may be formed by at least partially melting at least one of the container 20 and the lid 50. The bonding line 30 may also be formed by components separate from the container 20 and the lid 50, such as an adhesive. By forming the joint line 30 between the lid 50 and the flange portion 25, the housing portion 28 of the container 20 can be sealed without any gap. Although FIG. 3 shows an example in which the bonding line 30 is formed to extend over both the lid 50 and the flange portion 25, it is not limited thereto. For example, the bonding line 30 may be formed only on the lid 50 side, or may be formed only on the flange portion 25 side.

  As shown in FIG. 2, the joint line 30 is disposed on the main line 32 extending along the outer edge 25 y of the flange portion 25 and the long side 25 a of the flange portion 25 and protrudes inward from the main line 32. And a line 34. The protruding line 34 is configured to be peeled off first when the pressure in the storage portion 28 of the container 20 increases with heating. The specific shape of the protruding line 34 will be described later.

  As shown in FIG. 2, it is preferable that the protruding line 34 be disposed on the protruding portion 26 of the long side 25 a. In addition, in FIG. 2, the example by which the protrusion line 34 is each arrange | positioned on a pair of long side 25a of the flange part 25 is shown. However, the present invention is not limited to this, and although not illustrated, the protruding line 34 may be disposed only on one of the pair of long sides 25 a of the flange portion 25.

  As shown in FIGS. 1 to 3, the bottom surface 21 of the container 20 may be formed with a raised portion 21 b that protrudes upward. Moreover, the some recessed part 21a may be formed in the protruding part 21b. By this, when cooking the contents using a microwave oven, it is possible to suppress that the container 20 is deformed when the pressure of the storage portion 28 is increased. Further, as shown in FIG. 1, a step 23 a may be formed on the side surface 23 of the container 20.

(lid)
Next, the lid 50 joined to the container 20 will be described. The material making up the lid 50 is chosen such that the lower surface of the lid 50 can be joined at least to the upper surface of the flange 25 of the container 20. For example, the lid 50 includes a base material layer and a sealant layer that constitutes the lower surface of the lid 50. The thickness of the lid 50 is, for example, in the range of 20 to 100 μm.

  As a material which comprises a base material layer, polyester-type resin, such as a polyethylene terephthalate, polyamide-type resin, such as nylon, polypropylene etc. can be used. Moreover, as a material which comprises a sealant layer, polypropylene, mixed resin of polypropylene and polyethylene, etc. can be used. When both the substrate layer and the sealant layer contain polypropylene, biaxially oriented polypropylene is used in the substrate layer, and non-oriented polypropylene is used in the sealant layer.

(Shape of protrusion and protrusion line)
Next, with reference to FIGS. 4 and 5, the shape of the projecting portion 26 of the flange portion 25 and the shape of the projecting line 34 of the joint line 30 will be described in detail. FIG. 4 is an enlarged plan view of 30 projecting lines 34 of the joint line of the lidded container 10 shown in FIG. 5 is an enlarged view of the protruding line 34 as in FIG. 4, and is a view for explaining the shapes of the protruding line 34 and the protruding portion 26. As shown in FIG.

  As shown in FIG. 4, the protruding line 34 of the joint line 30 includes a pair of first portions 35 extending inward from the main line 32 and a second portion 36 connecting the pair of first portions 35. It is. For this reason, the protruding line 34 has a substantially triangular shape that protrudes inward. In this case, when the pressure in the storage portion 28 of the container 20 is increased with heating, the substantially triangular tip of the protruding line 34 protruding inward, that is, the second portion 36 is peeled off, and the location of the second portion 36 At this time, the lid 50 comes off from the projection 26 of the flange 25.

  In FIG. 2, the symbol P represents the protrusion length of the protrusion line 34 with respect to the main line 32. The protrusion length P is defined by the inner edge 30x of the second portion 36 of the protrusion line 34 of the bonding line 30 and the inner edge 30x of the main line 32 connected to the first portion 35 of the protrusion line 34 in the direction in which the short side 25b extends. It is defined as the distance between

  In FIG. 5, θ1 represents an angle formed by a pair of first portions 35 extending inward from the main line 32. When the angle θ1 is large, the certainty that the protruding line 34 is first peeled off in the bonding line 30 is reduced when the pressure in the housing portion 28 is increased. On the other hand, when the angle θ1 is small, the projecting line 34 is partially formed based on the impact applied to the lidded container 10, for example, while the lidded container 10 is being transported, before the lidded container 10 is heated. There is a high possibility of peeling off. In consideration of these points, the angle θ1 between the pair of first portions 35 is preferably set in the range of 70 to 110 degrees, and more preferably set in the range of 80 to 100 degrees .

  Moreover, in order to suppress that the 2nd part 36 peels in the step before the container 10 with a lid is heated, as shown to FIG. 4 and FIG. It is preferable to have a curved shape that is convex toward the This can enhance the impact resistance of the second portion 36. The radius of curvature r in the curved shape of the second portion 36 is, for example, equal to or less than the width W3 of the second portion 36 of the protruding line 34.

  As shown in FIG. 4, the inner edge 25x of the protrusion 26 of the flange 25 of the container 20 includes a pair of first sides 26a extending inward and a second side 26b connecting the pair of first sides 26a. Contains. As in the case of the second portion 36 of the protrusion line 34, the second side 26b of the protrusion 26 preferably has a curved shape that is convex inward.

  In FIG. 5, θ2 represents an angle formed by a pair of first sides 26a extending inward. Generally, the angle θ2 between the pair of first sides 26a is set larger than the angle θ1 between the pair of first portions 35. Therefore, when the lid 50 is welded to the upper surface of the flange portion 25 of the container 20 to form the bonding line 30, the position of the lid 50 is deviated with respect to the direction in which the outer edge 25y of the flange portion 25 extends. Even if the projection line 34 is present, the projection line 34 can easily fall within the range of the projection 26.

  Next, the widths of the flange portion 25 and the joint line 30 will be described with reference to FIG. Here, “width” means the dimensions of the flange 25 and the joint line 30 in the direction orthogonal to the direction in which the outer edge 25 y of the long side 25 a of the flange 25 extends. In FIG. 4, the symbol W represents the width of the protrusion 26 of the flange 25. Reference symbol W1 represents the width of the region between the inner edge 30x of the second portion 36 of the protrusion line 34 of the joint line 30 and the inner edge 25x of the protrusion 26 of the flange 25. Further, reference sign W2 represents the width of the region between the outer edge 30y of the second portion 36 of the protruding line 34 of the bonding line 30 and the outer edge 25y of the protruding portion 26 of the flange portion 25. W3 represents the width of the second portion 36 of the protruding line 34 of the bonding line 30.

  The width W of the projecting portion 26 of the flange portion 25 is preferably 10 mm or more, for example, in the range of 10 to 15 mm. The width W2 of the region between the outer edge 30y of the second portion 36 and the outer edge 25y of the protrusion 26 is preferably 5 mm or more, for example, in the range of 5 to 10 mm. By setting the width W and the width W2 in this manner, as described later, after the steam hole is formed at the location of the second portion 36 of the protruding line 34, the lid is closed when the pressure in the storage portion 28 decreases. 50 can be brought into close contact with the projection 26 of the flange 25.

  The width W3 of the second portion 36 of the protruding line 34 is, for example, in the range of 1 to 5 mm. The ranges of the width W and the width W2 described above may be defined as a ratio to the width W3 of the second portion 36. For example, the width W may be set in the range of 2 to 10 times the width W3. The width W2 may be set to a value larger than the sum of the width W1 and the width W3.

  The second portion 36 of the protruding line 34 is preferably formed to be located at the center of the long side 25 a of the flange portion 25. Specifically, a virtual straight line drawn so that the distance between the outer edge 25y of one short side 25b and the distance between the outer edge 25y of the other short side 25b are equal in plan view is A second portion 36 is formed to pass through the second portion 36. When the protruding lines 34 are respectively disposed on the pair of long sides 25 a of the flange portion 25, preferably, the tip of the inner edge 30 x of the second portion 36 of one protruding line 34 and the other protruding line 34 A protruding line 34 is formed on a straight line connecting the tip of the inner edge 30x of the second portion 36 so that the center point 20c of the container 20 described later is located.

(Method of manufacturing a container with a lid)
Next, an example of a method of manufacturing the lidded container 10 will be described.

  First, the container 20 having the bottom 21, the side 23, and the flange 25 integrally formed is formed by injection molding using a thermoplastic resin such as polypropylene. The thickness T (see FIG. 3) of the flange portion 25 is set, for example, in the range of 0.5 to 2.0 mm. In addition, a lid 50 having a contour corresponding to the flange portion 25 of the container 20 is prepared. Next, the storage portion 28 of the container 20 is filled with the contents. Thereafter, the lid 50 is placed on the upper surface of the flange portion 25 of the container 20. Next, the portion of the lid 50 where the bonding line 30 is to be formed is heated from the upper surface side using a hot plate or the like to melt the sealant layer of the lid 50. As a result, the bonding line 30 for welding the lid 50 to the upper surface of the flange portion 25 of the container 20 can be formed. Thus, the lidded container 10 including the container 20 and the lid 50 joined to the upper surface of the flange portion 25 of the container 20 via the joining line 30 can be obtained. At this time, a receiving plate may be disposed on the lower surface of the flange 25 to support the flange 25 without heating the flange 25.

(How to heat the contents)
Next, an example of a method of heating the contents stored in the storage portion 28 of the container 20 of the lidded container 10 will be described.

  First, the lidded container 10 with the bottom surface 21 of the container 20 facing downward is placed inside the microwave oven. Next, the contents are heated using a microwave oven. As a result, the temperature of the contents increases, and the water contained in the contents evaporates, and the pressure in the storage unit 28 increases. FIG. 6 shows a state in which the expanded portion 51 expanded upward from the upper surface of the flange portion 25 is formed on the lid 50 as the pressure of the accommodating portion 28 increases. As shown in FIG. 6, the bulge 51 is generally formed along the inner edge 25 x of the flange 25 around the center point 20 c of the container 20. Here, "the center point 20c of the container 20" is a middle point between the outer edge 25y of one long side 25a and the outer edge 25y of the other long side 25a in a plan view, and of one short side 25b. It is a point located at an intermediate point between the outer edge 25y and the other outer edge 25y. In addition, in FIG. 6 and FIG. 7A and 8A which are mentioned later, the recessed part 21a which may be formed in the bottom face 21 of the container 20, and the protruding part 21b are abbreviate | omitted.

  When the pressure in the housing portion 28 further increases with heating, the bulge portion 51 of the lid 50 is further expanded to reach the inner edge 25x of the flange portion 25 as shown in FIG. 7A. Here, in the present embodiment, the protruding line 34 of the bonding line 30 is disposed on the long side 25 a of the flange portion 25 of the container 20. Therefore, after reaching the inner edge 25x of the flange portion 25, the bulge portion 51 of the lid 50 first reaches the second portion 36 of the protrusion line 34 in the joint line 30. When the bulge 51 of the lid 50 reaches the second portion 36 of the protrusion line 34, the lid 50 is pulled upward with respect to the protrusion 26 of the flange 25 of the container 20 at the place where the second portion 36 is formed. Be When the force by which the lid 50 is pulled upward becomes greater than the bonding force of the second portion 36 of the protruding line 34, the second portion 36 is peeled off, so that the lid 50 is provided at the place where the second portion 36 is provided. Is separated from the projection 26 of the flange 25.

  FIG. 7B is a cross-sectional view showing the lidded container 10 shown in FIG. 7A as viewed along the line VIIB-VIIB. In the state shown in FIG. 7B, the lid 50 is peeled off from the projection 26 of the flange 25 at the place where the second portion 36 of the projection line 34 is provided. In the region between the outer edge 25y of the flange portion 25 and the second portion 36, the lid 50 and the flange portion 25 are not joined. Therefore, a steam hole is formed between the lid 50 and the flange portion 25 for discharging the vapor inside the housing portion 28 to the outside at the location where the second portion 36 of the protruding line 34 is provided. Ru. By this, the pressure of the accommodating part 28 can be reduced. For example, the pressure of the housing portion 28 can be matched to the external pressure (usually atmospheric pressure). By this, it is possible to heat the contents using the microwave oven while suppressing the occurrence of the rupture of the lid 50 and the like.

  Further, in the present embodiment, as described above, the protruding line 34 of the bonding line 30 is disposed on the long side 25 a of the flange portion 25 of the container 20. Therefore, the projecting line 34 can be more reliably peeled off from the lid 50 or the flange portion 25 earlier than the portion of the bonding line 30 other than the projecting line 34. For example, according to the present embodiment, as shown in FIG. 7A, the shortest distance from the center point 20c of the container 20 to the outer edge of the protruding line 34 of the joining line 30 is D1, and the flange portion 25 from the center point 20c of the container 20. The ratio of the shortest distance D2 to the shortest distance D1 is set to 1.50 or more, preferably 1.80 or more, when D2 is the shortest distance to the inner edge 30x of the main line 32 on the short side 25b of There is. For this reason, the distance from the center point 20 c of the container 20 to the bonding line 30 is shortest at the tip of the second portion 36 of the protruding line 34 of the bonding line 30. This leads to the largest angle of inclination that the bulge 51 makes with the horizontal direction at the tip of the second portion 36 of the projecting line 34. As a result, particularly the second portion 36 of the projecting line 34 on the long side 25 a of the flange 25 can be easily separated from the flange 25 before the main line 32 on the short side 25 b of the flange 25. it can. Therefore, the steam holes can be stably formed where the protruding lines 34 are provided. Therefore, the usability of the lidded container 10 can be improved.

  Further, in the present embodiment, as described above, the protruding lines 34 of the bonding line 30 are respectively disposed on the pair of long sides 25 a of the flange portion 25. Therefore, even if the location where the bulge portion 51 of the lid 50 is formed varies in the direction of the short side 25 b of the flange portion 25, at least one of the projecting lines 34 on the pair of long sides 25 a of the flange portion 25 is It can be made to peel more reliably. As a result, steam holes can be formed more stably at the places where the protruding lines 34 are provided.

  In FIG. 7B, the lid 50 is peeled off from the projection 26 of the flange 25 at the place where the second part 36 of the projection line 34 is provided by breaking the second part 36 of the projection line 34. An example is shown, but not limited thereto. Although not shown, if the second portion 36 of the protruding line 34 formed on the lid 50 side peels off from the flange portion 25, the second portion 36 of the protruding line 34 formed on the flange portion 25 side is a lid It may peel off from 50.

  When the heating of the contents using the microwave is finished, the temperature of the vapor in the storage unit 28 gradually decreases. For this reason, the pressure of the accommodating part 28 also falls gradually. At this time, the lid 50 may be in close contact with the flange portion 25 at the location where the second portion 36 of the protruding line 34 is provided or in the periphery thereof. For example, the lid 50 adheres to the flange portion 25 based on the surface tension of water droplets attached to the lid 50 and the flange portion 25 when the steam passes through the steam hole formed in the place where the second portion 36 is provided. It is conceivable. In this manner, when the temperature of the vapor in the storage unit 28 is further reduced after the storage unit 28 is sealed from the outside again, the pressure of the storage unit 28 becomes lower than the external pressure. That is, a negative pressure is generated in the housing portion 28. In this case, as shown in FIG. 8A, it is considered that a recess 53 recessed below the upper surface of the flange 25 is formed in the lid 50. The recess 53 is formed by recessing the lid 50 around the center point 20 c of the container 20. FIG. 8B is a cross-sectional view showing the lidded container 10 shown in FIG. 8A as viewed along line VIIIB-VIIIB. The recess 53 acts to generate a force to move the lid 50 downward toward the flange 25. Therefore, the lid 50 can be further in close contact with the flange portion 25.

  Further, in the present embodiment, as described above, the long side 25 a of the flange portion 25 is formed with the protruding portion 26 that protrudes inward. Therefore, the distance from the center point 20c of the container 20 to the inner edge 25x of the flange 25 is shortest at the tip of the projection 26 of the flange 25. This leads to the fact that the inclination angle of the recess 53 with respect to the horizontal direction is the largest at the tip of the protrusion 26. Therefore, the force F for pulling the lid 50 downward toward the flange 25 at the inner edge 25 x of the flange 25 is the largest at the tip of the projection 26. That is, the lid 50 is most likely to be in close contact with the upper surface of the flange portion 25 at the tip of the protrusion 26. Further, a protruding line 34 in which the steam hole is formed is disposed on the protruding portion 26. For this reason, as compared with the case where the protruding portion 26 is not formed, the lid 50 is firmly flanged at the portion where the steam hole is formed in the bonding line 30, that is, particularly at the second portion 36 of the protruding line 34. It can be adhered to the upper surface of 25. By this, it is possible to suppress the contents from spilling out of the containing portion 28 after the heating of the contents is completed. For example, even if the lidded container 10 is inclined when the lidded container 10 is taken out of the microwave, the contents may be spilled by bringing the lid 50 into tight contact with the flange portion 25. Can be suppressed.

  For example, as a result of conducting the following experiment with respect to the container 10 with a lid | cover in which water was accommodated as a content, the effect which suppresses that water spills was confirmed. Specifically, first, the lid 50 was welded to the flange portion 25 of the container 20 containing water having a volume of about half the volume of the container 20, thereby producing the lidded container 10 containing water. . Next, a steam hole was formed between the lid 50 and the flange portion 25 by heating water using a microwave oven. Then, after the temperature of the steam was lowered and the lid 50 was in close contact with the flange portion 25, the lidded container 10 was turned upside down so that the lid 50 was positioned below the container 20. In this state, it was confirmed that water did not spill from the lidded container 10.

  Further, in the present embodiment, as described above, the width W of the protrusion 26 of the flange 25 is in the range of 10 to 15 mm, and the outer edge 30 y of the second portion 36 and the outer edge 25 y of the protrusion 26 And the width W2 of the area between them is in the range of 5 to 10 mm. Therefore, the area of the flange portion 25 for sealing the housing portion 28 can be sufficiently secured by closely attaching the lid 50 at the place where the second portion 36 of the protruding line 34 is provided and in the periphery thereof. This can further suppress spilling of the contents from the accommodation portion 28.

  Note that various modifications can be made to the embodiment described above. Hereinafter, modifications will be described with reference to the drawings as needed. In the following description and the drawings used in the following description, with respect to parts that can be configured in the same manner as the above-described embodiment, the same reference numerals as those used for the corresponding parts in the above-described embodiment are used. Duplicate descriptions will be omitted. In addition, in the case where it is clear that the effects and advantages obtained in the above-described embodiment can be obtained also in the modified example, the description may be omitted.

(Modified example of flange)
In the above-described embodiment, the protrusion 26 is formed on the long side 25 a of the flange 25 of the container 20, and the protrusion line 34 of the bonding line 30 is disposed on the protrusion 26. However, the present invention is not limited to this, and as shown in FIG. 9, the protrusion 26 may not be formed on the long side 25 a of the flange 25. Even in this case, the protruding line 34 of the bonding line 30 is disposed on the long side 25 a of the flange portion 25 and the ratio of the shortest distance D2 to the shortest distance D1 is 1.50 or more. The protruding line 34 can be peeled off from the lid 50 or the flange 25 prior to the other parts.

Reference Signs List 10 container with lid 20 container 21 bottom surface 23 side surface 24 protrusion 25 flange 25a long side 25b short side 25c corner 25x inner edge 25y outer edge 26 protrusion 26a first side 26b second side 28 housing 30 joint line 30x inner edge 30y outer edge 32 main line 34 protruding line 35 first portion 36 second portion 50 lid 51 bulged portion 52 contour 53 recessed portion 54 contour

Claims (6)

A container in which a housing portion is formed;
A lid joined to the container to seal the receptacle of the container;
The container has a bottom surface, a side surface erected from the bottom surface so as to extend over the entire circumference along the outer edge of the bottom surface, and a flange portion connected to an upper portion of the side surface and the lid is joined. ,
The contour of the flange portion of the container includes a pair of long sides and a pair of short sides,
Between the lid and the flange portion of the container, a joining line for joining the lid and the flange portion is continuously formed over one circumference.
The joint line has a main line extending along the outer edge of the flange, and a protruding line disposed on the long side of the flange and protruding inward from the main line,
The shortest distance from the center point of the container to the outer edge of the protruding line of the joining line is D1, and the shortest distance from the center point of the container to the inner edge of the main line on the short side of the flange is D2. when the state, and are the ratio of D2 is 1.50 or more with respect to D1,
The flange portion has a protrusion formed on the long side so as to protrude inward.
The protruding line of the joining line is disposed on the protruding portion of the flange portion,
The protruding line includes a pair of first portions extending inward from the main line, and a second portion connecting the pair of first portions.
The projecting portion of the flange portion includes a pair of first sides extending inward and a second side connecting the pair of first sides.
The lidded container , wherein the angle θ2 between the pair of first sides of the protrusion is larger than the angle θ1 between the pair of first portions of the protrusion line .   The lidded container according to claim 1, wherein the protruding lines of the joining line are respectively disposed on the pair of long sides of the flange portion. The lidded container according to claim 1 , wherein the second portion of the protruding line has a curved shape that is convex inward. The lidded container according to any one of claims 1 to 3, wherein the projecting portions are respectively formed on the pair of long sides of the flange portion. The lidded container according to any one of claims 1 to 4 , wherein a width of the protruding portion of the flange portion is in a range of 10 to 15 mm. The lidded container according to any one of claims 1 to 5 , wherein the shortest distance from the outer edge of the projecting portion of the flange portion to the outer edge of the projecting line of the joining line is in the range of 5 to 10 mm. .

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