JP7542476B2 - Microwave cooking bag - Google Patents

Description

The present invention relates to a microwave cooking bag that can hold food ingredients and the like inside and can be heated in a microwave oven.

Conventionally, microwave cooking bags (hereinafter also referred to as cooking bags) that can store various ingredients and the like and heat and cook them in a microwave oven are known. Such cooking bags include those that store ingredients in a frozen state in advance to form frozen foods, and those that are standalone bags that allow users to store their favorite ingredients and heat and cook them in a microwave oven.

When food is placed in the cooking bag and heated in a microwave oven, the internal pressure increases and the cooking bag bursts, so it is known to provide a steaming mechanism in part of the cooking bag that allows steam to pass through when the internal pressure is increased. For example, Patent Document 1 discloses a cooking bag in which a polymerized part (glued part) that is easily peeled off when the internal pressure of the storage part increases is formed on part of the side of the cooking bag. The polymerized part is composed of an easily peelable seal with an easy-open film interposed therebetween, and further, by forming an easily steaming part of a roughly semi-elliptical shape in the center of the tip of the polymerized part, it is configured to be easily peeled off at that part to allow steam to pass through when the internal pressure increases.

It is also known that a cooking bag having a polymerized portion as described above is purchased by a user, who then places his or her favorite ingredients inside the bag and heats and cooks the ingredients in a microwave oven. Such cooking bags are formed with an openable zipper, and the user opens the zipper to fill the bag with his or her favorite ingredients and seasonings, closes the zipper, and heats and cooks the food in the microwave oven.

Patent Publication 2000-185777

In the cooking bag described above, microwave heating is often continued even after steam has passed through the steam passing mechanism in order to thoroughly warm or cook the food inside. As described above, the steam passing mechanism is composed of an easily peelable seal, such as an easy-open film, so once steam has passed through, the passageway remains wide, making it easy for outside air to flow in. For this reason, the cooking bag cannot remain closed after microwave heating is completed.
As described above, once a conventional cooking bag has been used in a microwave oven, the steaming mechanism remains open, and so subsequent use will result in the contents leaking out or outside air getting into the bag, meaning that the bag cannot be stored again and reheated in a microwave oven for use.

The present invention was made with a focus on the above-mentioned problems, and aims to provide a microwave cooking bag that can hold foodstuffs in the storage section, heat and cook them in a microwave oven, and then heat them again in the microwave oven for use.

To achieve the above object, the microwave cooking bag of the present invention has a storage section in which the contents are stored by overlapping sheet members and welding the periphery, and an overlapping section formed at the middle position of one side of the storage section by overlapping a part of the sheet members so as to protrude from the side, and the overlapping section is characterized in that both side sections are welded and multiple welded sections are intermittently formed at a predetermined interval on the tip side between the both side sections.

When the internal pressure of the container increases during heating in a microwave oven, the microwave oven applies pressure to the polymerized portion. Since the polymerized portion has multiple welded portions intermittently formed at a predetermined interval, steam can pass through the gaps between the welded portions. Since the polymerized portion is not an easily peelable seal, even if steam passes through once, the passage does not remain wide, and it is possible to prevent outside air from entering. In other words, when the internal pressure increases during heating in a microwave oven, even if steam passes through the polymerized portion once, the passage does not remain wide, so it is possible to prevent outside air from entering and to allow almost all of the internal steam to escape, which makes it possible to store the bag in the freezer as is after the first heating process and use it for heating a second time.

In order to achieve the above-mentioned object, the microwave cooking bag of the present invention has a storage section in which the contents are stored by overlapping sheet members and welding the periphery, and a polymerization section formed at the middle position of one side of the storage section by overlapping parts of the sheet members so as to protrude from the side, and the polymerization section has both side sections welded together, and a plurality of welded sections are intermittently formed at a predetermined interval on the tip side between the both side sections, and the polymerization section is provided with an easily peelable seal section over the area connected to the storage section on the base end side between the both side sections, and the easily peelable seal section is formed at an interval from the plurality of welded sections.

As described above, the present invention may be configured such that the polymerized portion is provided with an easily peelable seal portion. In such a configuration, instead of forming the entire polymerized portion with an easily peelable seal portion, a plurality of welded portions are intermittently formed at a predetermined interval on the tip side of the polymerized portion, and an easily peelable seal portion is provided on the base end side over the area connected to the storage portion. In such a configuration, even if the internal pressure of the storage portion increases and the easily peelable seal portion steams, the plurality of welded portions on the tip side can maintain their occlusion, preventing the inflow of outside air. This makes it possible to store the product frozen after the first heating process and use it for a second heating process.

The present invention provides a microwave cooking bag that can hold food ingredients in the storage section, heat and cook them in a microwave oven, and then heat them again in the microwave oven for use.

1 is a perspective view showing a first embodiment of a microwave cooking bag according to the present invention; FIG. 2 is an exploded perspective view of the electronic cooking bag shown in FIG. 1 . FIG. 2 is a plan view of the electronic cooking bag shown in FIG. 1 (welded portions are indicated by diagonal lines). 13 is a plan view showing a second embodiment of an electronic cooking bag (welded portions are indicated by diagonal lines). FIG. FIG. 11 is a plan view showing a third embodiment of an electronic cooking bag (welded portions are indicated by diagonal lines). FIG. 11 is a plan view showing a fourth embodiment of an electronic cooking bag (welded portions are indicated by diagonal lines). FIG. 13 is a plan view showing the configuration (part 1) of the polymerization section when verifying the balance between vapor permeability and obstruction property in the fourth embodiment, where (a) is a diagram showing a configuration in which a welding section is provided at a position corresponding to the easy vapor passage section, and (b) is a diagram showing a configuration in which a welding section is not provided at a position corresponding to the easy vapor passage section. FIG. 13 is a plan view showing the configuration (part 2) of the polymerization section when verifying the balance between vapor permeability and obstruction property in the fourth embodiment, where (a) is a diagram showing a configuration in which a welding section is provided at a position corresponding to the easy vapor passage section, and (b) is a diagram showing a configuration in which a welding section is not provided at a position corresponding to the easy vapor passage section. 13A and 13B are plan views showing the configuration of the polymerization section (part 3) when verifying the balance between vapor permeability and obstruction property in the fourth embodiment, in which (a) shows a configuration in which a welding section is provided at a position corresponding to the easy vapor passage section, and (b) shows a configuration in which a welding section is not provided at a position corresponding to the easy vapor passage section.

Below, an embodiment of the microwave cooking bag (cooking bag) according to the present invention will be described with reference to the drawings.

1 to 3 are diagrams showing a first embodiment of a microwave cooking bag according to the present invention, in which FIG. 1 is a perspective view, FIG. 2 is an exploded perspective view of the microwave cooking bag, and FIG. 3 is a plan view (welded parts are indicated by diagonal lines).
The cooking bag 1 of this embodiment has a main body 2 with a bag-shaped storage section S formed by overlapping a substantially rectangular sheet member 3 and a sheet member 4 composed of divided sheets 4A and 4B divided into upper and lower parts and having substantially the same shape as the sheet member 3, and welding the periphery (the welded part is indicated by diagonal lines). The cooking bag 1 shown in FIG. 1 has both side parts 2a and a lower end 2b welded, an upper end 2c not welded, and a known zipper 5 that can seal/open the storage section S is attached to the upper end side. Such a cooking bag 1 allows a user to fill the storage section S with ingredients, seasonings, etc. and cook in a microwave oven. Note that the cooking bag 1 can also be configured as a frozen food containing ingredients (a microwave cooking bag containing ingredients) by leaving the upper end 2c not welded, filling the storage section S of the main body 2 with ingredients such as ingredients, and then welding the upper end 2c. Further, although the main body 2 in this embodiment is configured as a so-called triangular body, the present invention may also be configured as a free-standing bag having a bottom, a gusseted bag, or a pillow bag.

The sheet members 3 and 4 form the side surfaces of the main body 2. At the middle position (slightly upward in this embodiment) of one side surface of the main body 2 that forms the storage section S, a part of the sheet member is overlapped across the width to form an overlapping portion (palm portion) 7 that protrudes from the side surface. This overlapping portion 7 can be formed, for example, by bending the lower end of the divided sheet 4A and the upper end of the divided sheet 4B that form the sheet member 4 described above by the same length to form bent portions 4a and 4b, respectively, and then bringing these bent portions 4a and 4b into contact with each other and fusing both side portions 7a and 7a together (thermally fusing with a heat bar or the like).

The polymerized portion 7 can be formed by a generally known method when making the cooking bag 1, and the polymerized portion 7 is equipped with a steaming mechanism 10 that allows steam to pass when the internal pressure of the storage portion S increases.

The sheet members 3 and 4 are not particularly limited as long as they are used as food packaging materials (plastic materials) that have the necessary heat resistance when heated in a microwave oven. The base material constituting the sheet members 3 and 4 may be, for example, polyester resins such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT), polyolefin resins such as polyethylene (PE) and polypropylene (PP), halogenated polyolefin resins such as polyvinylidene chloride and polyvinylidene fluoride, polyamide resins such as nylon-6 and nylon-66, biaxially oriented or non-oriented resin films such as ethylene-vinyl alcohol copolymers, polypropylene/ethylene-vinyl alcohol copolymer co-extrusion resin films, non-oriented polypropylene (CPP), etc. In addition, a sealant layer made of a heat-melting resin such as a polyethylene resin such as low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, or high-density polyethylene, a polypropylene resin, or an ethylene-α-olefin copolymer is laminated on the inner layer side of the base material, making it possible to weld the sheet members together.

The sheet members 3 and 4 may further comprise a composite sheet material having a multi-layer structure, and the laminate structure may be appropriately selected according to the contents to be contained in the storage section S, and is not limited to a specific laminate structure or constituent materials. For example, a film sheet having gas barrier properties or a film sheet having light barrier properties may be laminated. The laminate structure described above may be produced by various known methods, such as using an extruder to produce a film of molten resin and form layers into a laminate, or by using a lamination method such as dry lamination to produce a film formed in advance.

The cooking bag 1 of this embodiment is formed with a vertical length H of 195 mm and a horizontal length L of 200 mm, and the protruding length H1 of the overlapping portion 7 is formed to be 25 mm. The overlapping portion 7 is a portion where the bent portion 4a at the lower end of the divided sheet 4A and the bent portion 4b at the upper end of the divided sheet 4B overlap, and is formed across the horizontal direction of the side of the main body 2, and both side portions 7a are welded. In addition, the overlapping portion 7 has a plurality of welded portions (welded spots having a predetermined shape) 12 intermittently formed at a predetermined interval between both side portions 7a, 7a.

These welded parts 12 may be formed at the tip side of the overlapping part 7, but in this embodiment, the welded parts 12 are arranged in a horizontal line and are formed to intermittently weld the tip edge 7A of the overlapping part 7. Specifically, the welded parts 12 are formed at equal intervals with a rectangular shape and the same size (horizontal length W2 is 10 mm, vertical length H2 is 5 mm), and the gap G (10 mm gap) between adjacent welded parts is designed to provide a steam passage function. In this way, with the welded parts 12 formed intermittently, even if steam passes through the gap, the gap G is closed by the welding force of each welded part 12 without maintaining the widened passage, and it is possible to provide the function of preventing the inflow of outside air.

The overlapping portion 7 has a seal portion 15 with an opening 15a in one portion formed at a distance (approximately 10 mm in the vertical direction) from the multiple welded portions 12 across the region (connection line 7B with the storage portion S) connected to the base end side between the side portions 7a, 7a. The seal portion 15 in this embodiment is formed with a vertical length H3 of approximately 10 mm on the side of the side portions 7a, 7a, and the opening 15a is formed in the central region of the seal portion 15 with a width W3 of approximately 30 mm.

By forming such a seal portion 15, it is possible to effectively prevent outside air from flowing into the storage section S after steam has passed through, and it is possible to ensure steam permeability and occlusion properties. In addition, in the seal portion 15 of this embodiment, the tip side welding line 15A is formed parallel to the connection line 7B, and the storage section side welding line 15B is formed in a tapered shape so as to approach the multiple welding portions 12, and is configured in a shape that allows steam to pass easily but makes it difficult for outside air to flow in.

According to the cooking bag 1 described above, when the internal pressure of the storage section S increases due to heating in a microwave oven, steam can pass through the gaps G between the openings 15a and the welded parts 12. Even if steam passes through each gap G, the welded parts 12, which are intermittently formed in the horizontal direction, do not cause the passage to widen, and the leading edge 7A of the polymerized part 7 exhibits a blocking effect, making it possible to prevent the inflow of outside air. In other words, the inflow of outside air is prevented, allowing almost all of the internal steam inside the storage section to escape, and after the first heating process, it can be frozen and used for a second heating process.

For example, the food in the storage section S can be heated once and sterilized with microwaves, and then frozen without removing the contents, preventing the inflow of outside air, making it possible to heat and cook the food again in a microwave oven. Alternatively, in the configuration of this embodiment, the zipper 5 can be opened and the food can be filled into the storage section S, and then the zipper 5 can be closed, and the food can be heated and cooked in this state, some of the contents can be removed, and the remainder can be frozen and stored as is, and then heated and cooked again in a microwave oven.

The cooking bag 1 as described above is preferably configured to allow easy steaming and prevent outside air from flowing in. In this embodiment, the sealing portion 15 is tapered so that the welding line 15B on the storage portion side approaches the multiple welding portions 12, making it easy for steam to flow toward the opening 15a and easy for steam to flow in, and the welding line 15A on the tip side is formed parallel to the connection line 7B, making it difficult for outside air to flow into the storage portion.

In particular, in this embodiment, some of the multiple welded portions 12 (shown as welded portion 12a) are formed in a position opposite the area where the opening 15a is formed, making it difficult for outside air to flow in (this effect will be described later). In addition, each welded portion 12 is formed at equal intervals and of the same size, and the leading edge 7A of the overlapping portion 7 is intermittently welded, making it possible to increase the occlusion of the leading edge 7A after steaming.

Next, another embodiment of the present invention will be described.
In the following embodiments, the same components as those in the first embodiment are given the same reference numerals, and detailed description thereof will be omitted.

FIG. 4 is a plan view showing a second embodiment of the electronic cooking bag (welded portions are indicated by diagonal lines).
In this embodiment, for the seal portion 15 formed on the base end side of the overlapping portion 7, a welding line 15A on the tip side and a welding line 15B on the storage portion side are both formed parallel to the connection line 7B of the overlapping portion 7. In this case, the vertical length H3 of the seal portion 15 is formed to be about 10 mm.

In this configuration, compared to the first embodiment, when the internal pressure of the storage section S increases, steam is less likely to escape because there is no taper, making it possible to increase the pressure resistance.

FIG. 5 is a plan view showing a third embodiment of the electronic cooking bag (welded portions are indicated by diagonal lines).
In this embodiment, unlike the above-described embodiment, a seal portion 15 is not formed on the base end side of the polymerization portion 7. In such a configuration, the unsealed area is increased, so that good vapor permeability can be obtained when the internal pressure of the storage portion increases.

FIG. 6 is a plan view showing a fourth embodiment of the electronic cooking bag (welded portions are indicated by diagonal lines).
In the above embodiment, the polymerized portion 7 formed on one side of the cooking bag is characterized by not being easily peelable sealed, but such an easily peelable sealed portion may be provided on the polymerized portion 7 as long as the tip side of the polymerized portion 7 does not remain open after steaming. That is, instead of the above-mentioned seal portion 15, an easily peelable sealed portion 20 (part shown in a lattice pattern) with an easy-open film interposed therebetween may be provided on the base end side of the polymerized portion 7, and the welded portions 12 may be intermittently formed on the tip side of the easily peelable sealed portion 20 with a predetermined gap therebetween, as in the above-mentioned embodiment.

The easily peelable seal portion 20 is composed of an easily peelable layer with low peel strength so that it can be easily peeled off when the internal pressure of the storage portion increases, and as is well known, it can be formed, for example, by interposing a film tape (easy-open film) made of a polyolefin-based resin, or by laminating such resins.
In this embodiment, the overlapping portion 7 is formed to have a protruding amount of 25 mm, and the welded portions 12 are arranged in a horizontal line in the same manner as in the above embodiment, and are formed so as to intermittently weld the leading edge 7A of the overlapping portion 7. The welded portions 12 are formed at equal intervals with the same size (horizontal length W2 is 10 mm, vertical length H2 is 5 mm), and are formed so that the gap between each welded portion is 10 mm. The vertical length H3 of the easily peelable seal portion 20 is formed to be about 17 mm.

It is preferable that the above-mentioned easily peelable seal portion 20 has an easily vapor-permeable portion 21 formed in a part thereof so that vapor can easily pass therethrough when the internal pressure of the storage portion increases.
In this embodiment, the easily vaporizable portion 21 is formed in the central region of the easily peelable seal portion 20, and for example, a notch (unwelded portion) 21a is formed on the storage portion side and a notch (unwelded portion) 21b is formed at a corresponding position on the tip side, thereby forming a narrow blocking portion (connecting portion) 21c in the central region.

In this configuration, when the internal pressure increases, pressure acts on the blocking portion 21c, causing this portion to peel off and allow steam to pass through, and similar to the embodiment described above, steam passes through each gap between the welded portions 12. And similar to the embodiment described above, even if steam passes through each gap, the welded portions 12 formed intermittently in the horizontal direction do not maintain the passage widened, and the leading edge 7A of the overlapping portion 7 exerts a blocking effect, making it possible to prevent the inflow of outside air.

Here, we will explain the results of tests that were conducted on the steam permeability, occlusion property, and pressure resistance of cooking bags made from samples of the cooking bags according to the first embodiment (configuration of FIG. 3), the second embodiment (configuration of FIG. 4), the third embodiment (configuration of FIG. 5), and the fourth embodiment (configuration of FIG. 6).

The film sheet constituting each cooking bag sample was made of a polyamide resin (Ny#15) laminated with a polyethylene resin (LLDPE#60) as a sealant layer. In the fourth embodiment, a film tape made of a polyolefin resin was used as the easy-peel seal portion 20.
Each sample was filled with 100 g of water and heated in a microwave oven at 600 W. After confirming that steam had escaped from the steam passing mechanism 10, the sample was heated in the microwave oven for an additional minute and then the heating was stopped. In this state, the steam passing property and blocking property of each sample were evaluated on a three-level scale (good, bad, or bad).

Regarding vapor permeability, bags that made little noise when steam passed through the steam port (gap) were rated as ◯, bags that made a loud noise as △, and bags that broke as X. Regarding blocking ability, bags that had lost most of the air and had many contact points between the sheet and the liquid surface were rated as ◯, bags that had some air remaining (film spreads and is difficult to block) as △, and bags that did not block at all (inflated state is maintained) were rated as X.
Furthermore, each sample was also tested for pressure resistance. In this pressure resistance test, each sample was placed in an atmosphere of 90°C for 1 minute, and then air was pumped in at 1.0 L/min, and the maximum pressure until the internal pressure was released was used for evaluation. This pressure resistance test was then carried out a second time under the same conditions after steaming.
The results of the evaluation test are shown below.

The above test results show that in the third embodiment shown in Figure 5, the unsealed portion of the polymerization section 7 is wide, so the vapor permeability is good, but the wide unsealed portion tends to allow steam to escape and remain open (allowing outside air to flow in), and the sealability due to reduced pressure is poor. In other words, the result shows that it is not very suitable for a second use. However, the pressure resistance was approximately the same for the first and second uses, although the values were low.

In contrast, in the second embodiment shown in FIG. 4, by forming a seal portion 15 on the base end side of the polymerization portion 7, it becomes difficult for air to flow in after steaming, and it is possible to achieve higher occlusion than the third embodiment (evaluation between ◯ and △). In addition, the pressure resistance was high and the results were approximately the same for the first and second runs. As a result, it is predicted that the internal pressure required for steaming during microwave heating will be higher. Furthermore, in the first embodiment shown in FIG. 3, by forming a taper in the seal portion 15, it is possible to maintain even better steaming and occlusion compared to the second embodiment, while obtaining approximately the same pressure resistance for the first and second runs, as in the third embodiment.

In the fourth embodiment shown in FIG. 6, a good balance of vapor permeability and occlusion was obtained, as in the second embodiment, but the behavior of the first and second steam passes was different in terms of pressure resistance. That is, in the first steam pass, the easily peelable seal portion 20 was sealed, and the sealed state was maintained, resulting in high pressure resistance, but in the second steam pass, the easily peelable seal portion 20 had already peeled off, and this state was maintained, resulting in low pressure resistance. For this reason, the same pressure resistance was not obtained when used multiple times, and the balance of vapor permeability, occlusion, and pressure resistance was somewhat inferior compared to the first and second embodiments.

Based on the above test results, it is considered preferable to form the welded portion 12 continuously so as to intermittently close the tip side of the overlapping portion 7, particularly the tip edge 7A, as in the cooking bags of the first and second embodiments, and to form a seal portion 15 with an opening 15a in part over the area connected to the storage portion (the base end position of the overlapping portion).

Next, the results of verifying the balance between the configuration of the intermittently formed welded portion and the vapor permeability/blocking property in the polymerization portion 7 will be described with reference to Figs. 7 to 9.
The sample used in this verification, like the fourth embodiment, had an easily peelable seal portion 20 formed on the base end side of the polymerization portion 7, and an easily vaporizable portion 21 formed in the center thereof. The welded portions 12 were formed intermittently on the tip end side of the polymerization portion 7, with the spacing G between adjacent welded portions being 10 mm, and the vertical length H2 being 5 mm, which were the same for all samples, and the horizontal length W2 was 10 mm for the sample in Fig. 7, 20 mm for the sample in Fig. 8, and 30 mm for the sample in Fig. 9.

Figure 7(a) shows a configuration in which the welded portion 12 is formed intermittently at a position opposite the region that becomes the opening of the easily vapor-passing portion 21 (the region where the blocking portion 21c is formed) (such a welded portion is indicated by the symbol 12a). Also, Figure 7(b) shows a configuration in which the welded portion 12 is formed intermittently at a position opposite the region that becomes the opening of the easily vapor-passing portion 21 (the region where the blocking portion 21c is formed) (the welded portion 12b is formed offset from the region that becomes the opening, and when the blocking portion 21c is peeled off, steam can pass directly through the gap between the welded portions 12b).

When such a sample was filled with the same amount of water and heated in a microwave oven under the same conditions, the results showed that the balance between vapor permeability and occlusion was good for the configuration in Figure 7(a). This is thought to be because the welded portion 12a formed in a position opposite the opening area effectively prevented outside air from entering after vapor permeation.

In addition, even in the configurations shown in Figs. 8(a) and 8(b) where the length of the welded portion is 20 mm, and in the configurations shown in Figs. 9(a) and 9(b) where the length of the welded portion is 30 mm, the results showed that the configurations shown in Figs. 8(a) and 9(a) had a better balance of vapor permeability and occlusion, as in the configuration shown in Fig. 7. That is, in the configurations where the welded portion is intermittently formed on the tip side of the overlapping portion, forming the welded portion at a position opposite the opening area where the internal pressure of the storage portion increases and vapor is allowed to pass (a position that prevents vapor passage) can suppress the inflow of outside air and improve the balance of vapor permeability and occlusion. When the configurations shown in Figs. 7, 8, and 9 were compared and verified, better results were obtained for the shorter length W2 of the welded portion.

Based on the above verification results, when forming intermittent welded parts 12 in the polymerization part 7, it is considered preferable to configure the welded parts so that at least a part of them is within the opening of the steam passage part, and to form multiple welded parts with short lengths along the longitudinal direction of the polymerization part.

Although the embodiment of the present invention has been described above, the present invention is not limited to the configuration of the above-mentioned embodiment, and various modifications are possible.
The cooking bag 1 can be modified in various sizes and shapes, and the welded parts 12 formed in the overlapping parts 7 can also be modified in various sizes and shapes. The welded parts 12 do not have to be arranged in a straight line, and the gaps between the welded parts and their positions can be modified as appropriate. Furthermore, the shape of the seal part 15, the position where the opening is formed and its size, etc. can also be modified as appropriate.

1. Cooking bag (microwave cooking bag)
2 Main body 3, 4, 4A, 4B Sheet member 7 Laminated portion 12, 12a, 12b Welded portion 15 Sealed portion 15a Opening 20 Easily peelable sealed portion 21 Easily vapor-permeable portion S Storage portion

Claims (4)

a storage section in which an item is stored by stacking sheet members and welding the periphery of the sheet members;
an overlapping portion formed by overlapping a part of the sheet member at a middle position of one side surface constituting the storage portion and protruding from the side surface,
The overlapping portion has both side portions welded together, and a seal portion having an opening of width W3 is formed in a central region between the both side portions,
A plurality of welded portions having a width W2 are intermittently formed at a predetermined interval on the tip edge of the overlapping portion, so that a plurality of gaps are intermittently formed between the welded portions,
The width W2 of the welded portion is smaller than the width W3 of the opening,
A microwave cooking bag according to claim 1, wherein a part of said plurality of welded portions and gaps on both sides thereof are formed in a position opposite to a central region in which an opening is formed in said sealed portion. The opening is formed in a central region of the seal portion,
2. The microwave cooking bag according to claim 1, wherein the sealing portion is tapered so that the welding lines on the housing portion side approach the plurality of welding portions. 3. The microwave cooking bag according to claim 1, wherein the plurality of welded portions are formed at equal intervals between both side portions of the overlapping portion. 4. The microwave cooking bag according to claim 1, wherein the sheet member is formed with a zipper for opening and closing the storage section.

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