CN107264994B

CN107264994B - Container for microwave oven

Info

Publication number: CN107264994B
Application number: CN201710191267.7A
Authority: CN
Inventors: 山嵜大辅; 丸山久美雄
Original assignee: Kyoraku Co Ltd
Current assignee: Kyoraku Co Ltd
Priority date: 2016-03-31
Filing date: 2017-03-28
Publication date: 2020-06-23
Anticipated expiration: 2037-03-28
Also published as: TW201736218A; JP2017178430A; JP6730586B2; WO2017169964A1; CN107264994A; TWI634059B

Abstract

Provided is a container for a microwave oven, which can adjust the discharge amount of steam, restrain the buzzer sound when discharging steam and prevent the water drop from being detained in the structure that can prevent the leakage of the content. A container (10) for a microwave oven includes: the container comprises a container body (20) having an opening (21) at the upper part, a flange part (22) formed in a manner of extending from the opening (21) of the container body (20) to the outside, and a 1 st heat fusion part (23B) of a film-shaped cover part which is arranged on the whole circumference of the upper surface of the flange part (22) and is heat-fused to the closed opening (21), wherein the 1 st heat fusion part (23B) is provided with an easy stripping part (27) which is closed towards the outside when viewed from the plane, and the easy stripping part (27) is stripped from the outer tip part (27a) thereof.

Description

Container for microwave oven

Technical Field

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

Background

Conventionally, various techniques have been proposed for a container for a microwave oven (for example, see patent document 1).

Patent document 1 discloses the following technique: a sealed container having a peelable heat seal tape for automatically opening a part of the container by an increase in internal pressure due to steam expansion or the like, wherein at least one position of the heat seal tape is formed to protrude in the direction of the inside of the container, and the tip of the inside of the protrusion (a V-shaped portion protruding inward) is opened by the increase in internal pressure.

However, this technique has the following problems: the amount of steam discharged is difficult to adjust, the peeling of the V-shaped portion begins too early, the braising effect of the contents is poor, and the distance from the inner tip of the V-shaped portion to the end of the lid member is relatively long, so that a buzzer sounds when the steam is discharged. Further, there are problems as follows: since the lid member is likely to peel off widely, when the pressure is reduced after the steam is discharged, water droplets or a film constituting the lid member which are accumulated in a portion surrounded by the V-shape due to the discharge of the steam clog, and the container body is deformed due to the reduced pressure.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 62-235080

Disclosure of Invention

(problems to be solved by the invention)

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a container for a microwave oven, which can prevent the leakage of the contents more effectively, and which can adjust the amount of vapor discharged, suppress the buzzing sound at the time of vapor discharge, and prevent the stagnation of water droplets.

(means for solving the problems)

The present invention is achieved by the following configuration.

(1) A container for a microwave oven, comprising: the container comprises a container body having an opening at an upper portion thereof, a flange portion formed to extend outward from the opening of the container body, and a 1 st heat-fusion bonded portion provided on an entire periphery of an upper surface of the flange portion and heat-fused to a film-like lid member closing the opening, wherein the 1 st heat-fusion bonded portion has an easily peelable portion which is closed outward in a plan view, and the easily peelable portion is peeled from an outer tip portion thereof.

(2) The configuration of (1) further includes: a 2 nd heat fusion part which is provided so as to form a steam discharge part at a position corresponding to the easy-to-peel part on the outer peripheral side of the 1 st heat fusion part and is heat-fused to the lid member.

(3) In the structure of the above (1), the 1 st heat-fusion part is formed in a convex strip shape.

(4) In the structure of the above (2), the 2 nd heat-fusion-bonded part is formed in a convex strip shape.

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

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

(7) In the configuration of the above item (6), the easily peelable portion has an inner center distal end portion lower than the inner two base portions.

(8) In the configuration of the above (1), the 1 st heat fusion bonded part is formed in a band shape.

(9) In the configuration of the above (2), the 2 nd heat-fusion-bonded part is formed in a band shape.

(10) In the structure of any one of the above items (1), (8) and (9), the easily peelable portion has the outer tip portion that is higher than the inner two base portions.

(11) In the configuration of any one of the above items (1), (8), (9) and (10), the easy-peeling portion is formed of a W-shaped portion that is closed to the outside in a plan view.

(12) In the above-described configuration of (11), the easily peelable portion has an inner center distal end portion higher than the inner two base portions.

(13) In the structure described in any one of (1) to (12), the lid member further includes a protrusion that locks the lid member at a position on the flange portion that faces the outside of the vapor discharge portion so as not to adhere to the inside of the container main body during pressure reduction.

(Effect of the invention)

According to the present invention, it is possible to provide a container for a microwave oven, which can prevent water droplets from being accumulated by suppressing a buzzing sound at the time of steam discharge by adjusting the amount of steam discharge in a structure for preventing the leakage of contents more effectively.

Drawings

Fig. 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 a container body of a container for a microwave oven according to embodiment 1 of the present invention.

Fig. 3 is a perspective view showing a vapor vent part and an easily peelable part of a container body of a container for a microwave oven according to embodiment 1 of the present invention in an enlarged manner.

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

Fig. 5 is a cross-sectional view schematically showing a vapor discharge part and an easily peelable part of a container main body of a container for a microwave oven according to embodiment 1 of the present invention in an enlarged manner.

Fig. 6 is a view showing a state in which 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 where the lid member is peeled off by hand of the container for a microwave oven according to embodiment 1 of the present invention.

Fig. 8 is a cross-sectional view schematically showing a container for a microwave oven according to embodiment 2 of the present invention, in which a vapor discharge portion and an easily peelable portion of a container main body are enlarged in correspondence with fig. 5.

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

Fig. 10 is a plan view of a container body according to embodiment 4 of the present invention.

Fig. 11 is a cross-sectional view schematically showing a container for a microwave oven according to embodiment 4 of the present invention, with the vapor discharge portion and the peelable portion of the container main body enlarged in correspondence with fig. 5.

Detailed Description

Hereinafter, a mode for carrying out the present 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 given the same reference numerals,

(embodiment mode 1)

(integral constitution of Container for microwave oven)

First, the overall structure of a container for a microwave oven according to embodiment 1 will be described with reference to fig. 1. As shown in fig. 1, the container 10 for a microwave oven mainly includes a container body 20 having an opening 21 and filled with the content 11 from the opening 21, and a film-like lid member 50 closing the opening 21. Container body 20 and lid member 50 are both formed of a resin material. The contents 11 stored in the container body 20 are various foods and the like, and may be any type as long as they can be heated by a microwave oven.

In addition, the container 10 for a microwave oven includes: the flange portion 22, the 2 nd heat-fusion bonding portion 23A formed on the upper surface of the flange portion 22 and heat-fused to the lid member 50, and the 1 st heat-fusion bonding portion 23B on the outer peripheral side thereof. The container 10 for a microwave oven has a flange portion 22 and a protrusion portion 24 for locking the lid member 50. The 2 nd heat-fusion bonded part 23A is provided with a vapor discharge part 25, and the 1 st heat-fusion bonded part 23B is provided with an easily peelable part 27 (W-shaped part) at a position corresponding to the vapor discharge part 25. Hereinafter, the structure of each part of the container 10 for a microwave oven will be described with reference to fig. 1 to 3.

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

The flange 22 is formed to extend outward from the opening 21. The flange portion 22 has corner portions 22B at positions corresponding to four corners of the storage portion 20B at portions outside the inner portions (hereinafter referred to as "inner portions 22 a") where the 2 nd heat-fusion-bonded portion 23A and the 1 st heat-fusion-bonded portion 23B are provided. Each corner 22b is connected to the inner portion 22a via a step 22c, and is formed at a position lower than the inner portion 22 a.

Further, the inner portion 22a may be inclined downward with respect to the horizontal plane toward the extending end of the flange portion 22 by estimating the warpage of the container body 20 at the time of molding. The inclination of the flange portion 22 may be formed substantially uniformly over the entire circumference of the flange portion 22.

Returning to fig. 1. As shown in fig. 1, the lid member 50 has an outer periphery of substantially the same size as the outer periphery of the flange portion 22. After the storage portion 20B is filled with the contents 11, the lid member 50 is thermally welded (sealed) to the 2 nd thermal welding portion 23A and the 1 st thermal welding portion 23B to close the opening 21, thereby sealing the storage portion 20B.

As shown in fig. 2, the 2 nd heat fusion part 23A is formed in a convex stripe shape in addition to the steam discharge part 25 cut out for discharging steam in the entire circumference of the upper surface of the inner part 22a of the flange part 22, and is heat fused to the lid member 50. In this example, the vapor discharge portion 25 is provided in the vicinity of the inside of one corner portion 22b of the flange portion 22.

The 1 st heat-fused portion 23B is formed in a convex stripe shape so as to form a concave portion 26 on the inner peripheral side of the 2 nd heat-fused portion 23A, and is heat-fused to the lid member 50. The 1 st heat-fused portion 23B is formed on the entire periphery of the upper surface of the inner portion 22a of the flange portion 22. The 1 st heat-fusion bonded portion 23B is formed in a substantially quadrangular shape (substantially square in this example) on the upper surface of the inner portion 22a of the flange portion 22 so as to surround the opening 21 of the container body 20. The 1 st heat-fused part 23B has an outwardly facing W-shaped portion 27 (easily peelable portion) at a position corresponding to the vapor discharge portion 25 (see fig. 3).

Here, the 1 st heat fusion bonded portion 23B may be formed at a position lower than the 2 nd heat fusion bonded portion 23A. Accordingly, when the cover member 50 is pressed against the 2 nd heat fusion part 23A and the 1 st heat fusion part 23B from above by the weatherstrip (not shown), the pressing force of the weatherstrip against the 1 st heat fusion part 23B is smaller than the pressing force of the sealing strip against the 2 nd heat fusion part 23A, and therefore the welding strength with the cover member 50 at the 1 st heat fusion part 23B is lower than the welding strength with the cover member 50 at the 2 nd heat fusion part 23A. Thus, when the container 10 for a microwave oven is heated in a microwave oven and the vapor pressure in the storage portion 20B rises to a predetermined pressure, the lid member 50 peels off at a position of the sealing surface of the 1 st heat-fusion bonded portion 23B before the sealing surface of the 2 nd heat-fusion bonded portion 23A. That is, in the 2 nd heat fusion part 23A and the 1 st heat fusion part 23B, when the vapor pressure in the storage part 20B reaches a predetermined pressure, the sealing property between the 2 nd heat fusion part 23A and the lid member 50 is maintained, and the sealing property between the 1 st heat fusion part 23B and the lid member 50 is lost.

Further, by making the width of the 1 st heat-fusion bonded portion 23B smaller than the width of the 2 nd heat-fusion bonded portion 23A, the welding strength at the 1 st heat-fusion bonded portion 23B may be made lower than the welding strength at the 2 nd heat-fusion bonded portion 23A.

The recessed portion 26 is formed in a groove shape between the 2 nd heat-fusion bonded portion 23A and the 1 st heat-fusion bonded portion 23B, and has a function of guiding vapor from a position where the 1 st heat-fusion bonded portion 23B is peeled from the lid member 50 to the vapor discharge portion 25 when the vapor pressure in the storage portion 20B reaches a predetermined pressure.

The W-shaped portion 27 is formed as a W-shaped portion (see fig. 2) so as to be closed toward 1 corner portion 22b (toward the outside) of the flange portion 22 in a plan view. In the present embodiment, if the container 10 for a microwave oven is heated in a microwave oven as described later, steam is discharged from both

outer end portions

27a and 27a of the W-shaped portion 27 due to an increase in the steam pressure generated in the storage portion 20 b. Further, when the user pinches the end portion of the lid member 50 (in this example, the corner portion 50a of the lid member 50 shown in fig. 1) and pulls it up to peel the lid member 50 from the W-shaped portion 27, the force is concentrated on both outer side

distal end portions

27a, 27a of the W-shaped portion 27, and therefore the lid member 50 can be easily peeled with a small force.

In addition, in the case of peeling due to an increase in vapor pressure or peeling by a user, if the lid member 50 is easily peeled, it is desirable to combine materials that can be obtained by making a small force necessary to peel at least the 1 st heat fusion bonded portion 23B of the container body 20 and at least the back surface of the lid member 50. As a combination of materials which are easily peeled off, a combination of materials which are different from each other and which can be welded to each other may be used, and for example, a material obtained by mixing polypropylene (PP) with Polyethylene (PE) is used for at least the 1 st heat-welded part 23B of the container body 20, and Polyethylene (PE) is used for at least the back surface of the lid member 50.

Returning to fig. 3. As shown in fig. 3, the projection 24 is provided at a position on the corner 22b opposite to the outside of the vapor discharge portion 25. The protrusion 24 is disposed in the vicinity of the vapor discharge portion 25, and has a conical base portion 24a tapered upward and a spherical portion 24b formed on the upper portion of the base portion 24 a. The corner portion 50a (see fig. 1) of the lid member 50 is heat-welded to the spherical surface portion 24 b. The protrusion 24 functions to lock the corner 50a of the lid member 50 when the storage portion 20b is depressurized. By providing the protrusion 24 in the vicinity of the vapor discharge portion 25, the lid member 50 can be more prevented from adhering to the contents 11 when the storage portion 20b is depressurized. The configuration of the projection 24 is not particularly limited to this example, and may be any configuration as long as it can lock the corner 50a of the lid member 50 when the storage portion 20b is depressurized.

(W-shaped portion (easily peelable portion))

The W-shaped portion 27 (easily peelable portion) is described in more detail with reference to fig. 4 and 5. Fig. 4 shows the W-shaped portion 27 in an enlarged scale, and the W-shaped portion 27 is exploded as will be understood below. That is, the W-shaped portion 27 is composed of outer two distal end portions 27a, an inner center distal end portion 27b, inner two proximal end portions 27c, center two

side portions

27d, 27d connecting the outer two

distal end portions

27a, 27a and the inner center distal end portion 27b, and root two

side portions

27e, 27e connecting the outer two

distal end portions

27a, 27a and the inner two

proximal end portions

27c, 27 c.

By inclining the W-shaped portion 27 downward toward the outside in a side view as a whole, the W-shaped portion is configured to be peeled off from both the outside

distal end portions

27a, 27a regardless of peeling caused by an increase in vapor pressure generated in the housing portion 20b or peeling by a hand of a user as described above. If the details are observed further, it is as follows.

In the W-shaped portion 27, as shown in fig. 5, the outer side

distal end portions

27a, 27a are set lower than the inner side center distal end portion 27 b. Then, the

central side portions

27d and 27d connecting these portions are inclined downward outward at an inclination angle θ 1 with respect to the horizontal plane. With such a configuration, when lid member 50 is heat-welded to flange portion 22 of container body 20, outer

distal end portions

27a, 27a are more easily peeled off because they are less heat-welded than inner central distal end portion 27 b.

Here, the inner center distal end portion 27b may be the same height as or lower than the

inner root portions

27c, 27 c. Fig. 5 shows an example in which the inner center peak portion 27b is lower than the

inner root portions

27c, 27c by a height difference h 1. Since the center sides 27d, 27d are set shorter than the root sides 27e, the inner center distal end portion 27b is lower than the

inner root portions

27c, 27 c. By setting the relative lengths of the

central side portions

27d, 27d and the

root side portions

27e, 27e in this way, the strength of the thermal welding at the inner root portions 27c, the inner central tip portion 27b, and the

outer tip portions

27a, 27a can be adjusted. Further, since the root both

side portions

27e, 27e are inclined downward toward the outside at the inclination angle θ 1 with respect to the horizontal plane, the strength of the thermal welding of the center both

side portions

27d, 27d and the root both

side portions

27e, 27e is not changed.

The following results were obtained by repeating the experiment while changing the inclination angle θ 1 with respect to the sealability between the film constituting the lid member 50 and the central both

side portions

27d, 27d or the root both

side portions

27e, 27 e.

TABLE 1

Inclination angle (theta 1)	1.46	3.62	4.08	4.18	5.46	5.75	5.81
								Sealing property	Good effect	Good effect	Good effect	Good effect	Good effect	Not good	Not good

Based on this result, by setting the inclination angle θ 1 to 5.50 degrees or less, as described above, higher peelability can be obtained at both

outer edge portions

27a, 27a of the W-shaped portion 27 than at other portions.

(action)

Next, the operation of the microwave oven container 10 will be described with reference to fig. 6 and 7. As shown in fig. 6, when the container 10 for a microwave oven is heated in the microwave oven, the lid member 50 expands due to the increase of the vapor pressure generated in the storage portion 20 b. When the lid member 50 is expanded, the steam from the peeled off position, i.e., the outer both

distal end portions

27a, 27a is discharged to the outside from the steam discharging portion 25 as shown by the arrow (1) in fig. 6.

Then, as shown by an arrow (2) in fig. 7, the user picks up the lid member 50 corresponding to the steam discharging portion 25 by pinching the corner portion 50a thereof, and pulls up the lid member 50 to peel the lid member 50 from the protrusion portion 24 and the W-shaped portion 27. 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 can easily remove the lid member 50 from the container body 20.

(Effect of embodiment 1)

The effects of embodiment 1 explained above are described below. In embodiment 1, both outer side

distal end portions

27a and 27a of the W-shaped portion 27 (easily peelable portion) are peeled off first by vapor pressure, and the vapor is discharged from the same position. Thus, the steam discharge amount is adjusted by suppressing the width of the W-shaped portion 27 from peeling from the inside to the outside, and the braising effect of the content is maintained. Further, since the distance to the end of the lid member is short, the generation of a buzzer sound at the time of steam discharge is suppressed. Further, since water droplets do not stay in the V-shaped surrounded portion at the center of the W-shape when the pressure is reduced after the steam is discharged, and thus the container body 20 can be prevented from being deformed by the steam filled therein.

(embodiment mode 2)

Embodiment 2 of the present invention will be described below with reference to fig. 8. In embodiment 2, in the W-shaped portion 27 (easy-to-peel portion) in embodiment 1, the inner central peak portion 27b is made lower than the

inner root portions

27c and 27c, and the height difference is h 2. That is, the center both

side portions

27d, 27d connecting the outside both

distal end portions

27a, 27a and the inside center distal end portion 27b are formed at a more gentle inclination angle θ 2 than the root both

side portions

27e, 27e connecting the outside both

distal end portions

27a, 27a and the inside both

base portions

27c, 27 c. With such a configuration, when the lid member 50 is heat-welded to the flange portion 22 of the container body 20, the strength of heat welding can be further made different between the central both

side portions

27d, 27d and the root both

side portions

27e, 27e sandwiching the outer both distal end portions 27a, and therefore, the stress of vapor pressure against the outer both

distal end portions

27a, 27a is further concentrated and peeling is further facilitated.

As for the inclination angles θ 1 and θ 2, based on the results shown in table 1, both the inclination angles θ 1 and θ 2 are 5.50 degrees or less, and by making the inclination angle θ 2 smaller than the inclination angle θ 1 within this range, higher peelability can be obtained at both outer side

distal end portions

27a, 27a of the W-shaped portion 27 than at other portions as described above.

(embodiment mode 3)

Next, a container body according to embodiment 3 of the present invention is described based on fig. 9. In embodiment 3, the planar shape of the storage portion 20b is a substantially oval shape with rounded corners. As shown in fig. 9, the container body 70 has a storage portion 20b having a substantially rectangular planar shape and an opening 21. The flange portion 22 extending from the opening 21 is provided with a 2 nd heat fusion bonded portion 23A in a ridge shape and a 1 st heat fusion bonded portion 23B in a ridge shape. Furthermore, the 1 st heat-fusion bonded 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 outward at a position corresponding to the vapor discharge portion 25 in a plan view. The W-shaped portion 71 has: 2 outer

distal end portions

71a and 71a facing outward, 1 inner central distal end portion 71B facing inward, and two inner

proximal end portions

71c and 71c connected to the 1 st heat-fused portion 23B.

In the W-shaped portion 71, as in

embodiments

1 and 2, the 1 corner portion 22b of the flange portion 22 is inclined downward (outward) in a side view. That is, the outer

distal end portions

71a and 71a are set lower than the inner central distal end portion 71b, and the inner

proximal end portions

71c and 71c are set higher than the inner central distal end portion 71 b. The correspondence relationship between these elements is the same as that between the outer distal end portions 27a, the inner central distal end portion 27b, and the inner

proximal end portions

27c, 27c in embodiments 1 and 2 (see fig. 5 and 8). The welding strength at the outer both

distal end portions

71a, 71a of the W-shaped portion 71 can be set smaller than the other portions by this inclination.

When the user pinches the lid member 50 and pulls it upward to peel the lid member 50 from the W-shaped portion 71, the lid member 50 can be easily peeled with a smaller force by concentrating the force on at least one of the 2 outer

side edge portions

71a and 71a of the W-shaped portion 71. Further, when the lid member 50 is automatically opened by the increase in the vapor pressure, the stress concentrates on both

outer end portions

71a and 71a of the W-shaped portion 71, and therefore peeling is more likely to occur. Thus, similarly to

embodiments

1 and 2, the amount of steam discharged is adjusted by suppressing the width of the W-shaped portion 71 from peeling from the inside to the outside, and the braising effect of the contents is maintained. Further, since the distance to the end of the lid member is short, the generation of a buzzer sound at the time of steam discharge is suppressed. Further, since water droplets do not stay in the V-shaped surrounded portion at the center of the W-shape when the pressure is reduced after the steam is discharged, and thus the container body 20 can be prevented from being deformed by the steam filled therein.

In embodiment 3, as in

embodiments

1 and 2, the 1 st heat-fusion bonded portion 23B may be formed at a position lower than the 2 nd heat-fusion bonded portion 23A, or the width of the 1 st heat-fusion bonded portion 23B may be formed smaller than the width of the 2 nd heat-fusion bonded portion 23A. This makes it possible to set the welding strength of the 1 st heat-welded part 23B lower than that of the 2 nd heat-welded part 23A.

(embodiment mode 4)

Next, a container main body 80 according to embodiment 4 of the present invention is described based on fig. 10 and 11. In embodiment 4, the 2 nd heat-fusion bonded part 81A and the 1 st heat-fusion bonded part 81B in embodiment 2 are changed from a ridge shape to a band shape. As shown in fig. 10, the container body 80 has a storage portion 20b having a substantially rectangular planar shape and an opening 21. A band-shaped 2 nd heat fusion bonded portion 81A and a band-shaped 1 st heat fusion bonded portion 81B are formed at the flange portion 22 extending from the opening 21 (in fig. 10, each of the fusion bonded portions is a flat portion shown in a broken line manner). That is, the 2 nd heat fusion bonded part 81A and the 1 st heat fusion bonded part 81B are not in the shape of a ridge, but are formed in a flat shape in a range in which a space (non-heat fusion bonded part 82) through which steam can pass between the 2 nd heat fusion bonded part 81A and the 1 st heat fusion bonded part 81B can be realized. The 1 st heat-fusion bonded part 81B has a flat W-shaped part 71 closed outward at a position corresponding to the vapor discharge part 25 in a plan view.

The 1 st heat fusion part 81B is formed in a band shape by pressing a cap 90 (hot plate) against the flange 22 of the container body 80. The seal 90 is configured to have a thickness (a height lower when viewed downward from a base line of an upper portion of the seal 90) thinner at a position corresponding to the W-shaped portion 71 (easy-to-peel portion) than at a position other than the W-shaped portion 71. Specifically, the W-shaped portion 71 is formed by a heat-welding header 90 configured to correspond to the form of the W-shaped portion 71 of embodiment 2, for example, as shown in fig. 11. Of course, the configuration may be adapted to the configuration of the W-shaped portion 27 of embodiment 1. In fig. 11, a portion of the end cap 90 corresponding to the W-shaped portion 71 is given a symbol indicating a W-shaped structure 71'. That is, the end socket 90 includes outer distal end portions 71a ', inner central distal end portions 71 b', inner proximal end portions 71c ', central side portions 71 d', 71d 'connecting the outer distal end portions 71 a', 71a 'and the inner central distal end portion 71 b', and outer distal end portions 71e ', 71 e' connecting the outer distal end portions 71a ', 71 a' and the inner proximal end portions 71c ', 71 c'. By pressing the sealing head 90 against the flat upper surface of the flange 22 via the lid member 50, the W-shaped portion 71 welded to the lid member 50 is formed on the upper surface of the flange 22.

By pressing the end socket 90 against the flange 22, the W-shaped portion 71 is formed to have outer

distal end portions

71a and 71a which are weaker in heat fusion than the inner

proximal end portions

71c and 71 c. The inner central distal end portion 71b is formed to have a weaker strength than the

inner root portions

71c, 71c in thermal welding. That is, the W-shaped portion 71 of embodiment 4 is formed in a state where the W-shaped structure 71' of the sealing head 90 is inverted vertically.

That is, the

center side portions

71d and 71d connecting the outer side edge portions 71a and the inner side center edge portion 71b are inclined upward outward at an inclination angle θ 2 with respect to the horizontal plane. With such a configuration, when lid member 50 is heat-welded to flange 22 of container body 20, outer

distal portions

71a and 71a are lighter than inner central distal portion 71b in heat-welding, and therefore, are more likely to be peeled off.

In order to make the outer

distal end portions

71a, 71a more easily separable, both

side portions

71e, 71e connecting the outer

distal end portions

71a, 71a and the inner

proximal end portions

71c, 71c are inclined outward and upward at an inclination angle θ 1 with respect to the horizontal plane. The inclination angle θ 1 is configured to be larger than the inclination angle θ 2 of the

center side portions

71d, 71 d. With such a configuration, when the lid member 50 is heat-welded to the flange portion 22 of the container body 20, the strength of the heat welding is different between the central two

side portions

71d, 71d and the root two

side portions

71e, 71e sandwiching the outer two tip portions 71a, so that the stress of the vapor pressure with respect to the outer two

tip portions

27a, 27a is more concentrated and the separation is more easily performed.

Thus, similarly to

embodiments

(modification example)

In embodiments 1 to 4, the easy-peeling portion is formed of the W-shaped portion 27 or the W-shaped portion 71 which is closed to the outside in a plan view, but the shape is not limited to the W-shaped portion (including the V-shaped portion having 1 outer tip portion) which is pointed to the outside like the outer both

tip portions

27a and 27a or the outer both

tip portions

71a and 71a when the present invention is applied. Further, even if the easily peelable portion is formed of a U-shaped portion closed to the outside and the outer tip portion is formed of an arc-shaped member, for example, the same effects as those of the respective embodiments can be obtained.

(conclusion)

The present invention has been described above with reference to the embodiments, but it goes without saying that the technical scope of the present invention is not limited to the scope described in the embodiments. It will be apparent to those skilled in the art that various changes and modifications can be added to the embodiments described above. It is to be understood from the description of the scope of the claims that the present invention is intended to include modifications and improvements added thereto.

(description of reference numerals)

10: container for microwave oven

11: content(s) therein

20: container main body (embodiment 1, embodiment 2)

21: opening of the container

22: flange part

23A: no. 2 Heat-fusion bonded part (embodiment 1, embodiment 2)

23B: 1 st Heat-fusion bonded part (embodiment 1, embodiment 2)

24: protrusion part

25: steam discharge part

26: concave part

27: w-shaped portion (easy-to-peel portion) (embodiment 1, embodiment 2)

27 a: two outer tips

27 b: medial central tip

27 c: two inner roots

50: cover part

70: container main body (embodiment 3)

71: w-shaped portion (easy peel portion) (embodiments 3 and 4)

71 a: outer both ends (embodiment 3 and embodiment 4)

71 b: inner central tip part (embodiment 3, embodiment 4)

71 c: inner root parts (embodiment 3, embodiment 4)

80: container main body (embodiment 4)

81A: no. 2 Heat-fused part (embodiment 4)

81B: 1 st Heat-fusion bonded part (embodiment 4)

82: non-heat fusion part

90: sealing head (Hot plate)

Claims

1. A container for a microwave oven, comprising:

a container body having an opening at an upper portion thereof,

A flange portion formed to extend outward from the opening of the container body, and

a 1 st heat fusion part which is arranged on the whole circumference of the upper surface of the flange part and is heat fused to a film-shaped cover part for closing the opening,

the 1 st heat-fused part has an easy-to-peel part which is closed towards the outside in a plan view,

the easily peelable portion is peeled off from the outer tip portion thereof,

the easy-peeling part is formed by a W-shaped part which is closed towards the outer side in a plan view,

the easily peelable portion has an inner central tip portion which is weaker in heat fusion strength than the inner two root portions.

2. The container for a microwave oven according to claim 1, further comprising:

and a 2 nd heat fusion part which is provided at a position corresponding to the easy-to-peel part on the outer peripheral side of the 1 st heat fusion part to form a steam discharge part and is heat fused to the cover member.

3. A container for a microwave oven according to claim 1, wherein:

the 1 st heat welding part is formed into a convex strip shape.

4. A container for a microwave oven according to claim 2, wherein:

the 2 nd heat welding part is formed in a convex strip shape.

5. A container for a microwave oven according to any one of claims 1 to 4, characterized in that:

the easily peelable portion has the outer tip portion lower than the inner root portions.

6. A container for a microwave oven according to claim 1, wherein:

the easily peelable portion has an inner central peak portion lower than the inner root portions.

7. A container for a microwave oven according to claim 1, wherein:

the 1 st heat fusion part is formed in a strip shape.

8. A container for a microwave oven according to claim 2, wherein:

the 2 nd heat-fusion part is formed in a band shape.

9. A container for a microwave oven according to any one of claims 1, 7 and 8, wherein:

the easily peelable portion has the outer tip portion which is weaker in strength of thermal welding than the inner two root portions.

10. The container for a microwave oven according to any one of claims 2, 4 and 8, further comprising:

and a protrusion portion for locking the lid member at a position of the flange portion facing an outside of the vapor discharge portion so as not to adhere to an inside of the container main body at the time of pressure reduction.