TWI634059B - Microwave container - Google Patents

Abstract

Provided is a container for a microwave oven that adjusts the amount of vapor discharged in a structure that can prevent leakage of contents, thereby suppressing buzzing when vapor is discharged, and preventing water droplets from remaining. The container (10) for a microwave oven includes a container body (20) having an opening (21) at an upper portion thereof, a flange portion (22) formed to extend outward from an opening (21) of the container body (20), and The entire surface of the upper surface of the flange portion (22) is provided and thermally welded to the first heat-welded portion (23B) of the film-shaped cover member that closes the opening (21), and the first heat-welded portion (23B) has The easily peelable portion (27) which is closed toward the outside in plan view, the easily peelable portion (27) is peeled off from the outer tip end portion (27a).

Description

Microwave container

The present invention relates to a container for a microwave oven.

Conventionally, various techniques have been proposed for a container for a microwave oven (for example, refer to Patent Document 1).

Patent Document 1 discloses a technique in which a sealed container is provided with a peelable heat seal tape in order to automatically open a part of the container due to an increase in internal pressure due to vapor expansion or the like, and is formed as at least one of heat seal tapes. The position protrudes toward the inner side of the container, and the inner tip end of the projection (the V-shaped portion that protrudes toward the inner side) opens due to an increase in the internal pressure.

However, in this technique, there is a problem in that it is difficult to adjust the discharge amount of the vapor, and since the peeling of the V-shaped portion starts too early, the steaming effect of the contents is poor, from the inner tip end of the V-shaped portion to the end of the cover member. The distance between the parts is relatively long and causes a buzzing sound when the vapor is discharged. Further, there is a problem in that the peeling of the lid member is likely to be widened, and therefore, when the steam is discharged under pressure, the water droplets may be clogged by the water droplets in the portion surrounded by the V shape or the film constituting the lid member. The deformation of the container body caused by decompression.

[First technical literature] Patent literature

Patent Document 1: Japanese Laid-Open Patent Publication No. 62-235080

The present invention has been made in view of the above circumstances, and it is an object of the invention to provide a container for a microwave oven which can adjust the discharge amount of the vapor and prevent the buzzing sound during the discharge of the steam in a structure capable of better preventing leakage of the contents. Water droplets are stranded.

The present invention is grasped by the following configuration.

(1) A container for a microwave oven, comprising: a container body having an opening at an upper portion; a flange portion formed to extend outward from the opening of the container body; and a convex portion provided at the convex portion The entire upper surface of the edge portion is thermally welded to the first heat-welded portion of the film-shaped lid member that closes the opening, and the first heat-sealed portion has an easily peelable portion that is closed toward the outside in a plan view. The easily peelable portion is peeled off from the outer tip end portion thereof.

(2) The configuration of (1), further comprising: forming a vapor discharge portion at a position corresponding to the easily peelable portion on an outer peripheral side of the first heat seal portion and being thermally welded to Said The second heat seal portion of the cover member.

(3) In the configuration of (1), the first heat seal portion is formed in a convex strip shape.

(4) In the configuration of (2), the second heat seal portion is formed in a convex strip shape.

(5) In the configuration of any one of (1) to (4), the easily peelable portion has the outer tip end portion that is lower than the inner two portions.

(6) In the configuration of any one of (1) to (5), the easily peelable portion is formed in a W-shaped portion that is closed toward the outside in a plan view.

(7) In the configuration of (6), the easily peelable portion has an inner center tip end portion that is lower than the inner two portions.

(8) In the configuration of (1), the first heat seal portion is formed in a strip shape.

(9) In the configuration of (2), the second heat seal portion is formed in a strip shape.

(10) In the configuration of any one of (1), (8), and (9), the easily peelable portion has the outer tip end portion higher than the inner two portions.

(11) In the configuration of any one of (1), (8), (9), and (10), the easily peelable portion is formed in a W-shaped portion that is closed toward the outside in a plan view.

(12) In the configuration of (11), the easily peelable portion has an inner center tip end portion that is higher than the inner two portions.

(13) The configuration of any one of (1) to (12), further comprising locking the cover member to the inside so as not to adhere to the inside of the container body during decompression a protruding portion of the flange portion at a position facing the outer side of the vapor discharge portion.

According to the present invention, it is possible to provide a container for a microwave oven which can adjust the discharge amount of the vapor, suppress the buzzing sound at the time of vapor discharge, and prevent the water droplets from staying in the structure which can prevent the leakage of the content.

10‧‧‧Container for microwave ovens

11‧‧‧ contents

13‧‧‧Inside central tip

20‧‧‧Container body (Embodiment 1, Embodiment 2)

20a‧‧‧ bottom

20b‧‧‧Storage Department

21‧‧‧ openings

22‧‧‧Flange

22a‧‧‧ inside part

22b‧‧‧ corner

22c‧‧‧ steps

23A‧‧‧Second thermal fusion joint (Embodiment 1, Embodiment 2)

23B‧‧‧First thermal fusion joint (Embodiment 1, Embodiment 2)

24‧‧‧Protruding

24a‧‧‧ base

24b‧‧‧ spherical face

25‧‧‧Vapor Removal Department

26‧‧‧ recess

27‧‧‧W-shaped part (easy peeling part) (Embodiment 1, Embodiment 2)

27a‧‧‧The two outer tips

27b‧‧‧Inside central tip

27c‧‧‧ inside two roots

27d‧‧‧Two sides of the central

27e‧‧‧ Both sides

50‧‧‧ cover parts

50a‧‧‧ corner

70‧‧‧Container body (Embodiment 3)

71‧‧‧W-shaped part (easy peeling part) (Embodiment 3, Embodiment 4)

71a‧‧‧ outer two tip ends (Embodiment 3, Embodiment 4)

71b‧‧‧Inside central tip end portion (Embodiment 3, Embodiment 4)

71c‧‧‧ inside two parts (Embodiment 3, Embodiment 4)

71d‧‧‧The two sides of the central

71e‧‧ ‧ both sides

80‧‧‧Container body (Embodiment 4)

81A‧‧‧2nd Thermal Fusion Joint (Embodiment 4)

81B‧‧‧1st thermal fusion joint (Embodiment 4)

82‧‧‧Non-heat fusion joint

90‧‧‧Head (hot plate)

1 is an exploded perspective view of a container for a microwave oven according to Embodiment 1 of the present invention.

FIG. 2 is a plan view of the container body of the container for a microwave oven according to Embodiment 1 of the present invention.

FIG. 3 is an enlarged perspective view showing a vapor discharge portion and an easily peelable portion of the container body of the container for a microwave oven according to Embodiment 1 of the present invention.

FIG. 4 is a plan view showing an enlarged view of a vapor discharge portion and an easily peelable portion of the container body of the container for a microwave oven according to Embodiment 1 of the present invention.

FIG. 5 is an enlarged cross-sectional view schematically showing a vapor discharge portion and an easily peelable portion of the container body of the container for a microwave oven according to Embodiment 1 of the present invention.

FIG. 6 is a view showing a state in which the vapor of the container for a microwave oven according to Embodiment 1 of the present invention is discharged.

FIG. 7 is a view showing a state in which the lid member is peeled off by hand in the container for a microwave oven according to Embodiment 1 of the present invention.

FIG. 8 is a cross-sectional view showing the container for a microwave oven according to Embodiment 2 of the present invention, which is enlarged and schematically shown in the vapor discharge portion and the easily peelable portion of the container body in accordance with FIG. 5.

Fig. 9 is a plan view of a container body according to Embodiment 3 of the present invention.

Figure 10 is a plan view of a container body according to Embodiment 4 of the present invention.

FIG. 11 is a cross-sectional view showing the container for a microwave oven according to Embodiment 4 of the present invention, which is enlarged and schematically shown in the vapor discharge portion and the easily peelable portion of the container body in accordance with FIG. 5.

Hereinafter, a mode for carrying out the invention (hereinafter referred to as "embodiment") will be described in detail with reference to the drawings. In the entire description of the embodiments, the same elements are assigned the same schematic symbols.

(Embodiment 1) (The overall structure of the container for microwave oven)

First, the overall configuration of a container for a microwave oven according to Embodiment 1 will be described based on Fig. 1 . As shown in FIG. 1, the container 10 for a microwave oven has an opening 21 and fills the contents from the opening 21. The container main body 20 of 11 and the film-shaped cover member 50 which closes the opening 21 are main elements. Both the container body 20 and the lid member 50 are formed of a resin material. The contents 11 stored in the container body 20 are various foods and the like, and any type can be used as long as it can be heated in a microwave oven.

Further, the microwave oven container 10 includes a flange portion 22, a second heat seal portion 23A formed on the upper surface of the flange portion 22 and thermally bonded to the lid member 50, and a first heat seal portion 23B on the outer peripheral side thereof. Further, the microwave oven container 10 has a projection portion 24 that locks the cover member 50 at the flange portion 22. The second heat-sealed portion 23A is provided with a vapor discharge portion 25, and an easily peelable portion 27 (W-shaped portion) is provided at a position corresponding to the vapor discharge portion 25 of the first heat-welded portion 23B. Hereinafter, the configuration of each part of the microwave oven container 10 will be described based on FIG. 1 to FIG.

As shown in Fig. 2, the container body 20 has a housing portion 20b with a bottom 20a. The storage portion 20b, the bottom portion 20a, and the opening 21 are formed in a substantially quadrangular shape (in this example, a substantially square shape) having rounded corners in a plan view.

The flange portion 22 is formed to extend outward from the opening 21. In addition, the flange portion 22 is provided at the four corners of the housing portion 20b on the outer portion of the inner portion (hereinafter referred to as the "inner portion 22a") where the second heat seal portion 23A and the first heat seal portion 23B are provided. The position corresponding to each corner has a corner 22b. Each corner portion 22b is connected to the inner portion 22a via the step 22c, and is formed at a lower position than the inner portion 22a.

Further, it is also possible to preliminarily estimate the warpage at the time of molding of the container body 20 so that the inner portion 22a is formed. The extending end toward the flange portion 22 is inclined downward with respect to the horizontal surface. The inclination of such a flange portion 22 can be formed substantially the same around the entire circumference of the flange portion 22.

Go back to Figure 1. As shown in FIG. 1, the cover member 50 has an outer circumference that is substantially the same size as the outer circumference of the flange portion 22. After the contents 11 are filled in the storage portion 20b, the lid member 50 is thermally welded (sealed) to the second heat-fusible portion 23A and the first heat-sealed portion 23B, and the opening 21 is closed to close the storage portion 20b.

As shown in FIG. 2, the second heat-sealed portion 23A is formed in a convex shape in addition to the vapor discharge portion 25 cut out for discharging steam in the entire periphery of the upper surface of the inner portion 22a of the flange portion 22. It is thermally welded to the cover member 50. In this example, the vapor discharge portion 25 is provided in the vicinity of the inner side of one corner portion 22b of the flange portion 22.

The first heat-welded portion 23B is formed in a convex strip shape so as to form the concave portion 26 on the inner circumferential side of the second heat-welded portion 23A, and is thermally welded to the lid member 50. The first heat seal portion 23B is formed around the entire upper surface of the inner portion 22a of the flange portion 22. The first heat-welding portion 23B is formed in a substantially quadrangular shape (in the present example, a substantially square shape) so as to surround the opening 21 of the container body 20 on the upper surface of the inner portion 22a of the flange portion 22. Then, the first heat-sealed portion 23B has a W-shaped portion 27 (easy-peelable portion) facing outward at a position corresponding to the vapor discharge portion 25 (see FIG. 3).

Here, the first heat seal portion 23B may be formed at a position lower than the second heat seal portion 23A. Thereby, the sealing strip (not shown) is used with respect to the second heat seal portion 23A and the first heat seal portion. When the cover member 50 is pressed from above, the pressing force of the weather strip to the first heat-welded portion 23B is smaller than the pressing force of the weather strip to the second heat-welded portion 23A, so that the cover member 50 of the first heat-welded portion 23B is The welding strength is lower than the welding strength with the lid member 50 in the second heat-fusible portion 23A. Thus, when the microwave oven container 10 is heated in a microwave oven and the vapor pressure in the storage portion 20b rises to a predetermined pressure, the lid member 50 is at a certain position on the sealing surface of the first heat-welding portion 23B than the second heat-welding portion. The sealing surface of 23A is peeled off first. In other words, in the second heat-welding portion 23A and the first heat-welding portion 23B, when the vapor pressure in the storage portion 20b reaches a predetermined pressure, the sealing property of the second heat-welding portion 23A and the lid member 50 is maintained, and The sealing property of the heat-welding portion 23B and the lid member 50 is lost.

In addition, by making the width of the first heat seal portion 23B smaller than the width of the second heat seal portion 23A, the weld strength in the first heat seal portion 23B can be made lower than the weld strength in the second heat seal portion 23A.

The recessed portion 26 is formed in a groove shape between the second heat-sealed portion 23A and the first heat-welded portion 23B, and has a vapor pressure in the storage portion 20b reaching a predetermined pressure, and the first heat-welded portion 23B is at a certain position and a cover. When the member 50 is peeled off, the vapor from the peeled position is guided to the function of the vapor discharge portion 25.

The W-shaped portion 27 is formed as a W-shaped portion so as to be closed toward the one corner portion 22b (toward the outer side) of the flange portion 22 in plan view (see FIG. 2). In the present embodiment, when the microwave oven container 10 is heated by a microwave oven, the vapor is discharged from the outer edge portions 27a and 27a of the W-shaped portion 27 by the increase in the vapor pressure generated in the storage portion 20b. In addition, the user is holding the cover When the end portion of the member 50 (in this example, the corner portion 50a of the cover member 50 shown in Fig. 1) is pulled up and the cover member 50 is peeled off from the W-shaped portion 27, the force is also concentrated to the outer two tip portions of the W-shaped portion 27. Since the 27a and 27a sides, the cover member 50 can be easily peeled off with a small force.

Further, in consideration of peeling due to an increase in vapor pressure or peeling by a user, it is preferable that at least the first heat-welded portion 23B of the container body 20 and at least the back surface of the lid member 50 are peeled off in consideration of easy peeling of the lid member 50. A combination of materials that can be achieved with a small force. As a combination of materials that are easily peeled off, a combination of materials that can be welded but different from each other can be used. For example, at least the first heat-fusible portion 23B of the container body 20 is obtained by mixing polypropylene (PP) in polyethylene (PE). As the material, at least the back surface of the lid member 50 is made of polyethylene (PE) or the like.

Go back to Figure 3. As shown in FIG. 3, the protrusion 24 is provided at a position on the corner portion 22b facing the outside of the vapor discharge portion 25. The protruding portion 24 is disposed in the vicinity of the vapor discharge portion 25, and has a conical base portion 24a that is tapered toward the upper tip end, and a spherical portion 24b formed on the upper portion of the base portion 24a. The corner portion 50a (refer to FIG. 1) of the cover member 50 is thermally fused to the spherical portion 24b. The projection 24 functions to lock the corner portion 50a of the cover member 50 when the storage portion 20b is decompressed. By providing the protruding portion 24 in the vicinity of the vapor discharge portion 25, it is possible to more prevent the lid member 50 from adhering to the contents 11 when the storage portion 20b is decompressed. Further, the configuration of the protruding portion 24 is not particularly limited to this example, and may be any configuration as long as the corner portion 50a of the lid member 50 can be locked when the storage portion 20b is decompressed.

(W-shaped part (easy peeling part))

The W-shaped portion 27 (easy peeling portion) will be described in more detail with reference to FIGS. 4 and 5. Fig. 4 shows the W-shaped portion 27 in an enlarged manner, and the W-shaped portion 27 is disassembled as follows. That is, the W-shaped portion 27 is composed of the outer two tip end portions 27a, 27a; the inner central tip end portion 27b; the inner two root portions 27c, 27c; the central two side portions 27d, 27d connecting the outer two tip end portions 27a, 27a and the inner central tip end portion 27b; And the two side portions 27e and 27e that connect the outer end portions 27a and 27a and the inner two root portions 27c and 27c.

When the W-shaped portion 27 as a whole is inclined downward toward the outside in the side view, as described above, it is configured to be used by the user regardless of the peeling due to the increase in vapor pressure generated in the storage portion 20b. When the hand is peeled off, it is peeled off from the outer edge portions 27a and 27a. If the details are further observed, it is as follows.

In the W-shaped portion 27, as shown in Fig. 5, the outer tip end portions 27a, 27a are set lower than the inner center tip end portion 27b. Then, the central side portions 27d and 27d connecting them are inclined downward toward the outside with respect to the horizontal plane at an inclination angle θ1. According to this configuration, when the lid member 50 is thermally welded to the flange portion 22 of the container body 20, the outer tip end portions 27a and 27a are thermally welded to the inner center tip end portion 27b to a lesser extent, and therefore the peeling is more easily performed.

Here, the inner center tip end portion 27b may be the same height as or lower than the inner side root portions 27c, 27c. FIG. 5 shows an example in which the inner center tip end portion 27b is lower than the inner side root portions 27c and 27c, and the height difference is h1. Thus, since the center side portions 27d and 27d are set shorter than the root side portions 27e and 27e, the inner center tip end portion 27b is smaller than the inner side portions 27c and 27c. low. By setting the relative lengths of the central both side portions 27d and 27d and the both side portions 27e and 27e in this manner, the strength of heat fusion in the inner two root portions 27c and 27c, the inner center tip end portion 27b, and the outer tip end portions 27a and 27a can be adjusted. . Further, since the root side portions 27e and 27e are inclined downward toward the outside with respect to the horizontal plane at the inclination angle θ1, the strengths of the heat fusion of the central both side portions 27d and 27d and the root side portions 27e and 27e do not change.

The sealing property of the film constituting the lid member 50 and the central both side portions 27d and 27d or the both side portions 27e and 27e was repeated while the inclination angle θ1 was changed, and the following results were obtained.

By the result, the inclination angle θ 1 is 5.50 degrees or less, and as described above, the peeling property higher than the other portions can be obtained at the outer end portions 27a and 27a of the W-shaped portion 27.

(effect)

Next, the action of the container 10 for a microwave oven will be described based on FIGS. 6 and 7. As shown in FIG. 6, when the microwave oven container 10 is heated by a microwave oven, the cover member 50 expands due to an increase in the vapor pressure generated in the storage portion 20b. If the cover member 50 is inflated, the vapor from the peeled position, that is, the outer two tip end portions 27a, 27a is discharged from the vapor, as indicated by an arrow (1) in Fig. 6 . The portion 25 is discharged to the outside.

Then, the user picks up the corner portion 50a of the cover member 50 corresponding to the vapor discharge portion 25 as shown by an arrow (2) in Fig. 7, and pulls up the lid member 50 from the projection portion 24 and W. The shape 27 is peeled off. At this time, since the W-shaped portion 27 is formed to be closed toward the outside, the user can start the peeling of the lid member 50 with a smaller force, and the lid member 50 can be easily removed from the container body 20.

(Effect of Embodiment 1)

The effects of the first embodiment described above will be described. According to the first embodiment, the outer tip end portions 27a and 27a of the W-shaped portion 27 (easily peelable portion) are peeled off first by the vapor pressure, and the vapor is discharged from the same position. Thereby, by suppressing the extent of the peeling of the W-shaped portion 27 from the inside to the outside, the amount of vapor discharge is adjusted, and the steaming effect of the contents is maintained. Further, since the distance to the end of the cover member is short, the generation of buzzing sound when the vapor is discharged is suppressed. In addition, since the water droplets do not stay in the V-shaped portion in the center of the W shape when the steam is decompressed, the steam is discharged, and the container body 20 can be prevented from being deformed by the vapor filled inside.

(Embodiment 2)

Next, a second embodiment of the present invention will be described based on Fig. 8 . In the second embodiment, in the W-shaped portion 27 (easily peelable portion) in the first embodiment, the inner center tip end portion 27b is made lower than the inner side root portions 27c and 27c, and the height difference is h2. In other words, the central side portions 27d and 27d that connect the outer tip end portions 27a and 27a and the inner center tip end portion 27b are formed to be gentler than the root side portions 27e and 27e that connect the outer end portions 27a and 27a and the inner two end portions 27c and 27c. The inclination angle θ 2 . by According to this configuration, when the lid member 50 is thermally welded to the flange portion 22 of the container body 20, the central both side portions 27d and 27d and the both side portions 27e and 27e sandwiching the outer tip end portions 27a and 27a can be thermally welded. Since the strength is further different, the stress on the vapor pressure of the outer tip end portions 27a and 27a is more concentrated, and the peeling is easier.

Regarding the inclination angles θ 1 and θ 2 , based on the results shown in Table 1, the inclination angles θ 1 and θ 2 are both 5.50 degrees or less, and by making the inclination angle θ 2 smaller than the inclination angle θ 1 within this range, it is possible to As described above, the peeling property higher than the other portions is obtained at the outer end portions 27a and 27a of the W-shaped portion 27.

(Embodiment 3)

Next, a container body according to Embodiment 3 of the present invention will be described based on Fig. 9 . In the third embodiment, the planar shape of the storage portion 20b is a substantially oblong shape of a rounded corner. As shown in FIG. 9, the container body 70 has a storage portion 20b and an opening 21 having a substantially rectangular planar shape. The flange portion 22 extending from the opening 21 is provided with a second heat-fusible portion 23A having a convex shape and a first heat-welded portion 23B having a convex shape. Further, the first heat-welded portion 23B has a W-shaped portion 71, and the W-shaped portion 71 is formed in a W shape so as to be closed toward the outside at a position corresponding to the vapor discharge portion 25 in plan view. The W-shaped portion 71 has two outer end portions 71a and 71a that face outward, one inner center end portion 71b that faces inward, and two inner portions 71c and 71c that are connected to the first heat seal portion 23B.

Also in the W-shaped portion 71, similarly to the first embodiment and the second embodiment, the side view is In the drawing, the one corner portion 22b (toward the outer side) of the flange portion 22 is inclined downward. That is, the outer tip end portions 71a and 71a are set lower than the inner center tip end portion 71b, and the inner two root portions 71c and 71c are set higher than the inner center tip end portion 71b. The correspondence relationship between these is the same as the relationship between the outer tip end portions 27a and 27a, the inner center tip end portion 27b, and the inner side root portions 27c and 27c in the first embodiment and the second embodiment (see Figs. 5 and 8). By this inclination, the welding strength at the outer end portions 71a, 71a of the W-shaped portion 71 can be set smaller than the other portions.

When the user pulls on the lid member 50 and pulls the lid member 50 from the W-shaped portion 71, the force is concentrated on at least one of the two outer end portions 71a and 71a of the W-shaped portion 71, thereby The cover member 50 can be easily peeled off with a small force. Further, when the lid member 50 is automatically opened by the increase in the vapor pressure, stress is concentrated on the outer end portions 71a and 71a of the W-shaped portion 71, so that peeling is more likely to occur. As a result, in the same manner as in the first embodiment and the second embodiment, by suppressing the width of the W-shaped portion 71 peeling from the inside to the outside, the amount of vapor discharged is adjusted, and the steaming effect of the content is maintained. Further, since the distance to the end of the cover member is short, the generation of buzzing sound when the vapor is discharged is suppressed. In addition, since the water droplets do not stay in the V-shaped portion in the center of the W shape when the steam is decompressed, the steam is discharged, and the container body 20 can be prevented from being deformed by the vapor filled inside.

Further, in the third embodiment, similarly to the first embodiment and the second embodiment, the first heat seal portion 23B may be formed at a position lower than the second heat seal portion 23A, or the first heat seal portion 23B may be formed. The width is formed to be smaller than the width of the second heat seal portion 23A. Thereby, the welding strength of the first heat seal portion 23B can be set lower than the weld strength of the second heat seal portion 23A.

(Embodiment 4)

Next, a container body 80 according to Embodiment 4 of the present invention will be described based on FIGS. 10 and 11. In the fourth embodiment, the second heat seal portion 81A and the first heat seal portion 81B in the second embodiment are changed from a ridge shape to a belt shape. As shown in FIG. 10, the container body 80 has a storage portion 20b and an opening 21 having a substantially rectangular planar shape. The strip-shaped second heat-sealed portion 81A and the strip-shaped first heat-welded portion 81B are formed in the flange portion 22 extending from the opening 21 (in FIG. 10, each of the welded portions is shown by a broken line) Flat part). In other words, the second heat-sealed portion 81A and the first heat-welded portion 81B are not in the shape of a ridge, but are capable of passing a space between the second heat-welded portion 81A and the first heat-welded portion 81B (non-heating). The welded portion 82) is formed into a flat shape in the range. In addition, the first heat-sealed portion 81B has a W-shaped portion 71 that is closed to the outside at a position corresponding to the vapor discharge portion 25 and has a flat shape.

The first heat seal portion 81B is formed in a strip shape by pressing the head 90 (hot plate) to the flange portion 22 of the container body 80. The head 90 is configured to have a thickness thinner than a position other than the W-shaped portion 71 at a position corresponding to the W-shaped portion 71 (easy-peelable portion) (lower from the baseline of the upper portion of the head 90 toward the lower side) height). Specifically, the W-shaped portion 71 is formed by a cap 90 for heat fusion, and the cap 90 for thermal fusion is configured to correspond to, for example, the W-shaped portion 71 of the second embodiment as shown in FIG. 11 . Of course, it may correspond to the form of the W-shaped portion 27 of the first embodiment. In Fig. 11, a reference numeral of a portion indicating a W-shaped structure 71' corresponding to the W-shaped portion 71 is given to the head 90. That is, the head 90 is composed of the outer two tip end portions 71a', 71a'; the inner center tip end portion 71b'; the inner two root portions 71c', 71c'; and the outer two tip end portions 71a', 71a' and the central side edge portions 71d' and 71d' of the inner center tip end portion 71b'; and the root side portions 71e' and 71e' which connect the outer tip end portions 71a' and 71a' and the inner two root portions 71c' and 71c'. By pressing the head 90 against the flat upper surface of the flange portion 22 via the lid member 50, a W-shaped portion 71 welded to the lid member 50 is formed on the upper surface of the flange portion 22.

By pressing the head 90 against the flange portion 22, the W-shaped portion 71 is formed to have the outer end portions 71a, 71a which are weaker in heat fusion than the inner two portions 71c, 71c. Further, an inner center tip end portion 71b having a strength that is thermally welded to be weaker than the inner two root portions 71c and 71c is formed. That is, the W-shaped portion 71 of the fourth embodiment is formed in a state in which the W-shaped structure 71' of the head 90 is vertically inverted.

In other words, the central side portions 71d and 71d that connect the outer tip end portions 71a and 71a and the inner center tip end portion 71b are inclined upward toward the outside with respect to the horizontal plane by the inclination angle θ2. According to this configuration, when the lid member 50 is thermally welded to the flange portion 22 of the container body 20, the outer tip end portions 71a and 71a are thermally welded to a lower extent than the inner center tip end portion 71b, so that they are more easily peeled off.

Further, in order to make the outer end portions 71a and 71a more easily peeled off, the root side portions 71e and 71e connecting the outer end portions 71a and 71a and the inner two root portions 71c and 71c are inclined toward the horizontal plane by an inclination angle θ1. The outside is inclined upwards. The inclination angle θ 1 is configured to be an inclination angle larger than the inclination angle θ 2 of the central both side portions 71d and 71d. According to this configuration, when the lid member 50 is thermally welded to the flange portion 22 of the container body 20, the central both side portions 71d and 71d of the outer tip end portions 71a and 71a and the heat-sealing portions at the root side portions 71e and 71e are sandwiched. The strength is different, so The stress on the vapor pressure of the outer tip end portions 27a and 27a is more concentrated, and the peeling is more easily performed.

As a result, in the same manner as in the first embodiment and the second embodiment, by suppressing the width of the W-shaped portion 71 peeling from the inside to the outside, the amount of vapor discharged is adjusted, and the steaming effect of the content is maintained. Further, since the distance to the end of the cover member is short, the generation of buzzing sound when the vapor is discharged is suppressed. In addition, since the water droplets do not stay in the V-shaped portion in the center of the W shape when the steam is decompressed, the steam is discharged, and the container body 20 can be prevented from being deformed by the vapor filled inside.

(Modification)

In the first to fourth embodiments, the easily peelable portion is constituted by the W-shaped portion 27 or the W-shaped portion 71 that is closed toward the outside in plan view. However, when the present invention is applied, the shape is not limited to the outer two tip portions 27a. In the case of the 27a or the outer end portions 71a and 71a, a W-shaped portion having a pointed shape (including a V-shaped portion having one outer tip end portion) is formed outward. Further, even if, for example, the easily peelable portion is constituted by a U-shaped portion that is closed toward the outside, and the outer tip end portion is formed of an arc-shaped member, the same effects as those of the respective embodiments can be obtained.

(in conclusion)

The present invention has been described above by way of embodiments, but the technical scope of the present invention is not limited to the scope described in the embodiments, and it goes without saying. It will be apparent to those skilled in the art that various modifications and improvements can be added to the described embodiments. In addition, it is understood from the description of the patent application scope that the addition of such a modification or improvement should also be included in the present invention. Within the technical scope.

Claims (12)

A container for a microwave oven comprising: a container body having an opening at an upper portion; a flange portion formed to extend outward from the opening of the container body; and an entire circumference of the upper surface of the flange portion and being heated The first heat-welded portion of the film-shaped lid member that closes the opening, wherein the first heat-sealed portion has an easily peelable portion that is closed toward the outside in a plan view, and the easily peelable portion is peeled off from the outer tip end portion. And the easily peelable portion has the outer tip end portion whose heat fusion strength is weaker than the inner two root portions. The container for a microwave oven according to claim 1, further comprising: a portion in which a vapor discharge portion is formed at a position corresponding to the easily peelable portion on an outer peripheral side of the first heat seal portion, and is thermally welded to the lid member 2 heat fusion joints. The container for a microwave oven according to claim 1, wherein the first heat-welded portion is formed in a convex strip shape. The container for a microwave oven according to claim 2, wherein the second heat-welded portion is formed in a convex strip shape. The container for a microwave oven according to any one of claims 1 to 4, wherein the easily peelable portion has the outer tip end portion which is lower than the inner two portions. The container for a microwave oven according to any one of claims 1 to 4, wherein the easily peelable portion is formed in a W-shaped portion that is closed toward the outside in a plan view. A container for a microwave oven according to claim 6, wherein: The easily peelable portion has an inner center tip portion that is lower than the inner two portions. The container for a microwave oven according to claim 1, wherein the first heat-welded portion is formed in a strip shape. The container for a microwave oven according to claim 2, wherein the second heat-welded portion is formed in a strip shape. The container for a microwave oven according to any one of claims 1 to 8, wherein the easily peelable portion is formed in a W-shaped portion that is closed toward the outside in a plan view. The container for a microwave oven according to claim 10, wherein the easily peelable portion has an inner center tip end portion whose heat fusion strength is weaker than the inner two root portions. The container for a microwave oven according to any one of claims 1 to 4, 8 and 9, further comprising: locking the cover member to the flange portion so as not to adhere to the inside of the container body when decompressing A protruding portion at a position facing the outer side of the vapor discharge portion.