JPH07291366A - Cooking bag for microwave oven - Google Patents

Abstract

PURPOSE:To obtain a cooking bag for a microwave oven, that can be easily sealed only by folding the upper end part of the bag, can keep an internal pressure suitable for cooking and a cooking temperature to heat and cook a content, and can ensure a uniform heating and cooking effect. CONSTITUTION:In a self-standing bag, a synthetic resin film F having a heat resistance is used as a main component, front and rear wall parts 1a, 1b opposed to each other are bonded 3 at the both side edges thereof, a bottom part 2 connected to the lower edges of the front and rear wall parts 1a, 1b is tucked in between the front and rear wall parts so as to be formed into approximately an inverted V-shape in cross section, and both side ends of front and rear tucked pieces 2a, 2b of the bottom part 2 are bonded 4a, 4b to the front and rear wall parts 1a, 1b. The upper part of at least either the front or rear wall part is made of a paper material P. In at least the upper part within the height range of the tuck of the bottom part, the tucked pieces 2a, 2b of the bottom part 2 and the front and rear wall parts 1a, 1b are integrally bonded 5 at the both side ends thereof. The bottom part 2 can be curved into substantially a bilge form.

Description

Detailed Description of the Invention

[0001]

The present invention relates to, for example, boiled foods, steamed foods,
The present invention relates to a microwave oven cooking bag that can be easily used for cooking various foods such as teriyaki using a microwave oven.

[0002]

2. Description of the Related Art Conventionally, when cooking in a microwave oven, a special microwave oven cooking vessel such as a molded vessel made of a heat-resistant synthetic resin material is used, or a dish or the like is used. In general, the material was placed in the container and covered with a wrap film.

However, when these containers are used, it is necessary to clean up the cooking containers after cooking, and the containers are bulky, which requires a large storage space when not in use. There was a problem that disposal was difficult.

Therefore, in recent years, it has been considered to use a bag made of a heat-resistant synthetic resin film as a cooking bag in a microwave oven.

However, when the cooking bag is simply a flat bag, the self-standing of the cooking ingredients such as ingredients and seasoning liquid is unstable, and the seasoning liquid or soup stock may overflow. In addition, the convection effect of seasoning liquid or soup stock during heating and cooking is poor, and the ingredients do not evenly permeate into the ingredients, and uneven heating tends to occur, and satisfactory heating and seasoning effects can be obtained. Absent.

Further, it is considered to use a self-supporting bag as shown in Japanese Patent Publication No. 59-44261, for example, as a cooking bag in a microwave oven. In the case of this proposed bag,
Since the cooking ingredients are stored in the lower part of the bag, which has a relatively flat expanse due to the wing portions projecting forward and backward, the convection effect during cooking is poor, and it is not completely satisfactory in terms of heating and seasoning effects. .

[0007] In particular, regardless of which type of bag is used, if the upper part of the bag is left open during cooking in a microwave oven, the steam generated is discharged as it is, so the bag does not expand sufficiently. In addition to not being able to maintain a stable cooking temperature, excessive evaporation of water, burning, uneven heating, etc. are likely to occur, and the steaming effect cannot be obtained.

[0008] Therefore, it is necessary to perform a simple sealing that does not impair the air permeability. For this simple sealing, a dedicated closing means such as an adhesive tape, a clip or a fastener is used separately from the bag. Is required, and it is difficult to close it so that it has breathability suitable for cooking,
The sealing operation becomes troublesome. Providing a special sealing means in the opening of the bag itself increases the manufacturing cost of the bag itself and is not suitable as a disposable cooking bag.

The present invention has been made in view of the above,
The first purpose is that it has good self-sustaining property during heating and cooking, and by simply bending the upper end, it can be easily sealed to have a proper breathability, and it can maintain the internal pressure and heating temperature suitable for cooking. There is a microwave oven cooking bag that can be cooked by heating.

Another object of the present invention is to allow the bottom portion to be curved and expanded in a substantially boat bottom shape so that the ingredients for cooking can be uniformly impregnated with the convection action of seasoning liquid, soup stock or boiling water. The present invention provides a cooking bag for a microwave oven capable of obtaining uniform heating and seasoning effects.

Still another object of the present invention is that the bag is constructed by using a synthetic resin film as a main material and a paper material as a part thereof, but it can be joined by a heat fusion means and can be easily constructed. There is a microwave cooking bag that can be made.

[0012]

A cooking bag for a microwave oven according to a first aspect of the present invention for solving the above-mentioned problems is a self-supporting bag whose main component is a heat-resistant synthetic resin film,
At least one of the front and rear walls in the upper part of the bag is formed of a paper material having a dead hold property.

A cooking bag according to a second aspect of the present invention is formed of a heat-resistant synthetic resin film as a main material, the front and rear wall portions facing each other are joined at both side edges, and are continuously provided at the lower edges of the front and rear wall portions. A self-supporting bag having a bottom portion that is folded between the front and rear wall portions so as to form a substantially inverted V-shaped cross section, and both end portions of the bottom portion are joined to the front and rear wall portions. At least one of the front and rear wall portions in the upper part of the bag above the partial area is formed of a paper material having a dead hold property.

In the cooking bag according to the present invention, both side ends of the bottom portion folded in a substantially inverted V-shaped cross section have at least an upper portion of a folding height range having a substantially inverted V-shaped cross section.
It is preferable that the front and rear folding part pieces and the front and rear wall portions are integrally joined to each other, and the bottom portion is formed so as to be curved in a substantially boat bottom shape. In this case, it is particularly preferable to join the front and rear folded portions to the front and rear wall portions in an inclined shape from both side edges toward the lower edge.

Further, in the case of any of the above cooking bags,
The synthetic resin film as the main constituent material is a laminated film having a heat-fusible resin layer on the inner surface side of the bag of the base material layer made of a heat-resistant resin film, and the paper material at the top of the bag is made of long fiber pulp. It is preferable that the paper is made of the paper-making paper, which is joined by a heat fusion means to form a bag.

The above-mentioned long-fiber pulp is a pulp made from softwood, and has a relatively long fiber length, for example, 3
It has a thickness of not less than mm, is strong against pulling, and has a good heat fusion property with the film.

[0017]

Since the microwave cooking bag of the present invention described above is a self-supporting bag, it can be heated and cooked in a self-standing state by being housed in the lower part of the bag made of a heat-resistant synthetic resin film.
In the case of the cooking bag of the second aspect of the present invention, the bottom portion folded into the substantially inverted V-shaped cross section is curved downward and spreads out, so that the cooking bag can be stably maintained in an independent state. Further, in the case of the cooking bag according to the invention of claim 3, by opening the front and rear wall portions back and forth, the bottom portion is curved and swelled into a substantially boat bottom shape, and the cooking material is stored in the center portion of the bottom portion in a self-supporting state. Can be held at

In particular, since a part of the bag is made of paper material, the bending strength of the bag is increased, the self-sustaining property is improved as compared with the bag having only the synthetic resin film as a constituent material, and cooking is performed by heating. Occasionally, the bag will not fall or bend.

In heating and cooking, if the upper end of the cooking bag is only bent, the folded portion has a crease due to the dead-holding property of the paper material arranged on at least one of the front and rear walls of the bag. And kept in the simple sealed state.

Moreover, due to the simple sealing due to the above-mentioned bending, excessive discharge of steam generated during cooking is prevented, the internal pressure is increased, the bag in a self-supporting state is appropriately expanded, and convection of seasoning liquid or soup stock is carried out. Is done well. Then, when the internal pressure rises to some extent, a gap is created in the folded portion that is simply sealed against the dead-holding property of the paper material, and excess vapor is discharged to the outside due to the gap and the air permeability of the paper material itself. It Therefore, the inside of the bag is kept at an appropriate internal pressure, and an appropriate cooking temperature can be continuously maintained.

Particularly, in the case of the cooking bag constructed as in claim 3, since the bottom portion is curved and swells in a substantially boat bottom shape,
The stored cooking material gathers in the central part of the bottom, and the convection action of the seasoning liquid and the soup stock is carried out satisfactorily and uniformly, so that the taste of the cooking ingredient and the heating can be carried out uniformly.

Further, in the case of the cooking bag according to the present invention, although the paper material is partially used, it can be easily made into a bag by being joined by the heat fusion means. Particularly, the paper material is made of long fiber pulp. The paper material and the film have a good sealing property, and can have a bonding strength that can be used as a cooking bag.

[0023]

Embodiments of the present invention will now be described with reference to the drawings.

In the embodiments of FIGS. 1 to 6, (A) shows a cooking bag according to the present invention, which is a self-supporting bag mainly composed of a heat-resistant synthetic resin film (F).

In the cooking bag (A) of this embodiment, the front and rear wall portions (1a) and (1b) facing each other are joined at both side edges, and are integrally connected to the lower edges of the front and rear wall portions (1a) and (1b). It is provided with a bottom portion (2) folded between the front and rear wall portions (1a) and (1b) in a substantially inverted V-shaped cross section. The bottom part (2) is closed by joining the front and rear wall parts (1a) and (1b) to both side ends of the front and rear folding part pieces (2a) and (2b), respectively.
By opening the lower portions of the front and rear wall portions (1a) and (1b) forward and backward, the front and rear folding portion pieces (2a) and (2b) are expanded in a developed manner. That is, the cooking bag (A) can stand on its own with the bottom portion (2) widened.

(3) is a joining portion of both side edges of the front and rear wall portions (1a), (1b), and (4a) and (4b) are folding portion pieces (2a).
The joint part of (2b) and front wall part (1a) (1b) is shown.

Further, both side ends of the bottom portion (2) are folded in front of and behind the bottom portion (2) at an upper portion of a folding height range having a substantially inverted V-shaped cross section on an extension of the joint portion (3) of both side edges. Pieces (2a) (2b) and front and rear wall portions (1a) (1b)
Are joined together. As a result, the lower portion of the bag including the bottom portion (2) is restricted from protruding like a wing, and the bottom portion (2) is curved and swelled into a substantially boat bottom shape as shown in FIGS. 3 and 4. (5) shows the joint part (within the range of a dashed-dotted line). Due to the presence of the joint portion (5), the joint strength at the folding upper end position of the bottom portion (2) in the joint portion (3) is increased, and damage from the portion can be prevented.

Folding piece (2) before and after the bottom (2)
a) (2b) both side ends, front and rear wall portions (1a) (1b)
On the other hand, it is possible to join them on the extension of the joints (3) on both side edges, but the cooking ingredients (B) such as the cooking ingredients and seasonings housed in the bottom (2) As shown in the figure, the inner contour lines of the joints (4a) and (4b) are directed from the both side edges to the lower edge of the bottom portion (2) at the upper end position of the substantially V-shaped cross section as shown in the figure. It is desirable to join them in a slanted shape. The inclination angle of the inner contour line can be arbitrarily set in consideration of the form in which the bottom portion is expanded and widened. Furthermore, the inner contour lines of the joint portions (4a) and (4b) may be curved toward the lower edge and joined. In the case of the figure, the notch (6) is formed so as to leave the joints (4a) and (4b) from the lower end of the joint (5).

Further, the slanted joints (4
The front and rear wall portions (1a) and (1b) and the folded portion pieces (2a) and (2b) are joined to each other by the heat-sealing means also at the lower edge portion following the a) and (4b). (7a) and (7b) show the joints. The bottom part (2) has front and rear wall parts (1a) (1
In the case of one continuous from b), it is not always necessary to join the lower edge portion, but if the lower edge portion is joined as described above, the stability when the bag is inflated to be self-supporting is improved. The shape retention strength of the lower edge portion is also improved. Further, the bottom portion (2) may be joined and formed by a film different from the front and rear wall portions (1a) and (1b).

In the self-supporting bag having the above-mentioned configuration, the front and rear wall portions (1a) (1b) of the cooking material storage area, that is, the upper portion of the bag excluding the lower portion of the bag including the bottom portion (2).
And / or one of them, for example, the upper portion of the front wall portion (1a) as shown in the figure, is formed of a paper material (P) having an appropriate dead-hold property that can hold the bent state when bent. There is. This paper material (P) is the front wall (1a)
Is bonded to the film (F) constituting the lower part of the sheet by means of heat fusion means or the like. (8) shows the joint. The paper material (2) varies depending on the vertical and horizontal dimensions of the bag, the capacity, etc., but for example, as shown in the figure, the height of the paper material is 30 to 65 from the upper end.
%, Preferably 45 to 60%.

As the synthetic resin film (F) which is the main constituent, polyester resin films such as polyethylene terephthalate and polybutylene terephthalate, particularly crystallized polyester resin films,
With a moderately heat resistant and strong thermoplastic resin film as the base material layer, as a sealant layer on the inner surface side of the bag,
A heat-sealable resin film such as polypropylene resin is laminated by a dry laminating method, or a laminated film having a resin layer coated with the resin is
Its heat resistant temperature is 140 ° C. or higher, and it is particularly preferably used.

Of course, it is preferable to use a heat-resistant laminated film in which a heat-fusible resin layer is provided on a heat-resistant substrate layer other than the above, or a single heat-resistant film capable of being cooked. You can also The thickness can be appropriately set in consideration of strength in use, etc.
A few hundreds of microns are used. Further, an opaque film may be used, but a transparent film is preferable because the cooked state can be confirmed from the outside.

In the case of using the heat-fusible film (F) such as the above-mentioned laminated film, the respective joints (3) (4a) (4)
b), (5), (7a), (7b), and the joint portion (8) can be joined by a heat-sealing means, which facilitates bag making. Of course, it is also possible to use a bonding means using an adhesive to form a joint.

In the case of using the above-mentioned laminated film, the folded piece (2) of the bottom portion (2) folded in a substantially inverted cross section.
a) and (2b), the outer base material layers are in contact with each other. Therefore, the base material layer is cut off at the joint portions (5) at both end portions thereof, and at the cut-out portion. The inner resin layers may be heat-sealed together.

As the above-mentioned paper material (P), various kinds of papermaking paper having an appropriate dead-holding property when folded can be used, but among them, it has the air permeability through which vapor can pass. In addition, a papermaking paper made of long fiber pulp, which has a good heat fusion property with the film, is preferably used.

The paper material made of the long-fiber pulp has a good resin layer as a sealant layer when it is joined to the film (F) by heat-sealing means, and is sufficient for use as a cooking bag. It is possible to retain the bonding strength.

That is, a paper material made of long-fiber pulp [basis weight (metric basis weight): 73 g / m ² , thickness: about 106 microns] was examined for the bonding strength with the film used as the main constituent material. The results of (a) and (b) were obtained. Here, the following (a) uses a test piece having a width of 15 mm in which a laminated film of polyethylene terephthalate (base material layer) and polypropylene (resin layer) and the paper material are heat-sealed, and the film and the paper material are used. The strength when pulled in the peeling direction from each other is shown, (b) is the same test piece as described above,
The strength when the film and the paper material are pulled in the direction parallel to the heat-sealed surface is shown.

(A) 400 to 500 g / 15 mm, (b) about 4 kg / 15 mm Further, the air permeability of the same paper material as described above (JIS P8117).
Gurley method and water repellency (JIS P8137)
The results are as follows.

Air permeability: 25 sec / 100 cc / 645
mm ² Water repellency: R 8 to 9 As described above, the air permeability is considerably lower than that of the non-woven fabric and the like, and therefore the non-woven fabric has almost no effect of pressurizing the inside of the bag during cooking. Therefore, the inside of the bag can be sufficiently pressurized.

The paper material (P) is not necessarily required to have air permeability as long as it has the functions of dead-holding property and heat-sealing property with the film. In order to prevent the exudation of broth or the like that occurs during cooking in a microwave oven, it is desirable to have a suitable water repellency.

The thickness and basis weight of the paper material (P) can be appropriately set in consideration of the bulging form and strength during heating and the dead hold property and the like. For example, those having a thickness of several tens of microns or more, preferably several tens to several hundreds of microns are generally used. The basis weight is 50 to 80 g / m ² , and preferably 60 to 70 g / m ² . When the thickness and the basis weight are smaller than the above, the strength becomes weak and the dead hold property becomes poor. Further, if the thickness or basis weight, that is, the density is too large, the rigidity of the bag becomes too high, and the bulge form deteriorates.

The present invention can be carried out not only in the above-mentioned embodiment but also in a self-supporting bag having another bag form.

For example, the embodiment shown in FIG. 7 and FIG.
The basic structure of the bag is the same as that of the above-mentioned embodiment, but the joints (5) at both ends of the bottom (2) folded in a substantially inverted V shape.
In Fig. 1, a bag in a form in which front and rear folding part pieces (2a) (2b) and front and rear wall parts (1a) (1b) are continuously and integrally joined to the lower edge on the extension of the joint part (3) is shown. There is. In the case of this bag, expansion of both side ends of the bottom part (2) is restricted, and the lower part of the bag is held without protruding like a wing,
As shown in FIG. 8, the bottom portion (2) is curved into a substantially boat bottom shape and swells downward to be self-supporting. And in the bag of this form, as shown in the drawing, the front and rear wall portions (1a) (1b) on the upper part of the bag
At least one of them is formed of the same paper material (P) as described above. The same components as those in the above-mentioned embodiment are designated by the same reference numerals and the description thereof will be omitted.

Furthermore, the present invention, in addition to the above-mentioned embodiment,
Front and rear folding pieces (2a) of the bottom (2) at the bottom of the bag
At least one of the front and rear wall portions in the upper portion of the bag is formed by joining both side ends of (2b) to the front and rear wall portions (1a) and (1b) separately, and forming the bottom portion (2) so as to bulge and spread. It is also possible to carry out the above by forming the same paper material as described above. Further, in a self-supporting bag having another structure such as a square bottom bag, the main constituent material may be a heat resistant film, and a paper material may be used for at least one of the front and rear wall portions at the upper portion of the bag.

An example of using the cooking bag (A) described above is shown in FIGS.
The embodiment of FIG. 6 will be described.

Cooking materials such as ingredients for cooking in the bag (B)
Put in. At this time, the lower portions of the front and rear walls (1a) and (1b) are opened back and forth, so that the front and rear folding part (2
a) (2b) spreads out so as to spread back and forth, and is curved and bulges downward in a substantially boat-bottom shape (FIG. 4), and the material (B) has its bottom (2) as shown in FIG. Housed on top.

Next, after adding a special seasoning liquid, soup stock, etc., and thoroughly stirring, at the place where the upper end of the bag is about 30 to 40 mm from the opening end, the paper material (P) is placed outside, and the front and rear walls (1
a) Bend (1b) together and perform simple sealing. At this time, the paper material (P) has an appropriate dead-hold property, and the bent portion (P1) has a crease and is held in the simple sealed state by bending as it is. It is also possible to mark the bending position.

In this state, it is placed on a table in a microwave oven to stand on its own, and cooked for a period of time according to the dish.
At the time of this heating cooking, due to the above-mentioned simple sealing, excessive discharge of steam generated at the time of heating cooking is prevented and the internal pressure becomes high, and the cooking bag (A) in the self-supporting state is appropriately inflated, and the seasoning liquid is added. Good convection of soup stock.

Moreover, the internal pressure can be raised to a certain level, but as the internal pressure rises, the gap of the folded portion, which is simply sealed, is pushed against the dead-holding property of the paper material (P). The excess vapor is expanded to the outside by the air permeability of the gap and the paper material (P) itself. Therefore, inside the bag is moderate internal pressure (usually 1.01 ~
The temperature is maintained at 1.20 atm) and the proper cooking temperature can be continuously maintained. For example, the more cooking ingredients are oily, the higher the temperature is, and the less oily ingredients are 100-
It is maintained at 120 ° C., and a little higher (about 10 ° C. higher) for oily ones.

In addition, since the bottom portion (2) is curved and swelled into a substantially boat bottom shape, the cooking material (B) easily gathers in the central portion of the bottom portion (2) and the convection action of the seasoning liquid or the soup stock is performed. Satisfactorily, for example, boiling broth and the like convection along the curved shape of the inner surface of the bag so that it rises in the peripheral part and descends in the central part, thereby wrapping the entire ingredient, and this convection By the action, the ingredients are soaked in taste and heated uniformly. It can be said that this effect is equivalent to the drop lid effect generally recognized in cooking methods, and an extremely good cooking state is obtained.

Further, since the cooking material (B) is contained in the lower portion of the bag made of the heat-resistant film (F), even if boiling water or the like boils during cooking, the paper material (P) in the upper portion of the bag will not Even if the paper material (P) has water repellency, even if the paper material (P) does not come into direct contact with the paper material (P) Can be prevented.

By using the above-mentioned cooking bag (A), it is possible to cook by boiling, steaming, baking, etc.
There is no need to adjust the heat power as in cooking in a gas stove, and there is no risk of charring of the main constituents or overcooking of the cooking material (B).

By using the above-mentioned cooking bag (A), the viscosity of the cooking liquid is hardly restricted, and it can be used with a seasoning liquid of 1 to 2 centipoise or more, and there is no burning or uneven heating. .

Further, the above-mentioned cooking bag is small and can be folded in a small bulk during handling at the distribution stage and handling such as storage when not in use, and can be easily disposed of after use.

[0055]

As described above, according to the microwave oven cooking bag of the present invention, the heat-resistant synthetic resin film is used as the main constituent material, and the upper portion of the bag is made of the paper material having the dead hold property. Since the bag is made of a self-supporting bag, the cooking material can be contained and held in a self-supporting state with good stability, and there is no risk that the bag will fall over or be bent during cooking and the cooking material inside will overflow. Further, since the paper material is in the upper part of the bag and the cooking material is contained in the lower part of the bag made of a heat-resistant film, the paper material is not damaged by contact with boiling water or the like and can be used safely.

Moreover, by simply bending the upper end of the bag, the folded state can be maintained as it is due to the dead-holding property of the paper material, and the simple sealing state can be maintained, so that no other special closing means is required and the sealing is performed. It can be operated easily.

Moreover, due to the simple sealing by bending, the internal pressure is increased by the steam generated during heating and the cooking bag is appropriately inflated, and as the internal pressure rises, the gap between the bent portions and the ventilation of the paper material itself are increased. Since excess steam is discharged to the outside due to its nature, the inside of the bag can be kept at an appropriate internal pressure,
As a result, heating and cooking can be performed while maintaining an appropriate cooking temperature according to the type of dish. Moreover, since the internal pressure does not become excessively high, there is no fear of breaking the bag during cooking.

In particular, in the case of the cooking bag whose bottom portion is curved and swelled into a substantially boat bottom shape as in claim 3, the cooking ingredients are gathered in the central portion of the bottom portion, and the convection action of the seasoning liquid or the soup stock is performed. Is carried out satisfactorily, soaking in the taste of the ingredients and heating are carried out uniformly, and in combination with the effect of maintaining the internal pressure described above, good heating and seasoning can be obtained.

Further, in the case of the cooking bag according to the fourth aspect, although a paper material is partially used, the bag can be easily made by joining with the heat fusion means, and the paper material and the film can be sealed. Well, it has sufficient bonding strength to withstand use as a cooking bag, and can be easily manufactured at low cost.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention.

FIG. 2 is a perspective view of the same.

FIG. 3 is an enlarged cross-sectional view taken along line YY of FIG.

FIG. 4 is a perspective view showing a state in which a bottom portion of the same is expanded.

FIG. 5 is a perspective view from the bottom side of the above.

FIG. 6 is a perspective view showing a state in which cooking ingredients are accommodated.

FIG. 7 is a perspective view showing another embodiment of the present invention.

FIG. 8 is a perspective view showing a state in which a bottom portion of the same is expanded.

[Explanation of symbols]

 (1a) (1b) Front and rear wall parts (2) Bottom part (2a) (2b) Front and rear folding part pieces (3) Side edge joint parts (4a) (4b) Bottom part side end part joint parts ( 5) Front and rear integrated joints at both ends of the bottom (7a) (7b) Lower edge joint (8) Joint between paper and film (F) Film (P) Paper

Claims (4)

[Claims] 1. A self-supporting bag having a heat-resistant synthetic resin film as a main constituent material, wherein at least one of front and rear wall portions in the upper part of the bag is formed of a paper material having an appropriate dead-hold property. Cooking bag for microwave oven. 2. A heat-resistant synthetic resin film is used as a main component, front and rear wall portions facing each other are joined at both side edges, and the front and rear wall portions are connected to the lower edges to have a substantially inverted V-shaped cross section. A self-supporting bag having a bottom portion folded between the front and rear wall portions so that both side ends of the bottom portion are joined to the front and rear wall portions, and at least one of the front and rear wall portions in the upper portion of the bag is dead. A cooking bag for a microwave oven, which is formed of a paper material having a holding property. 3. The front and rear folding part pieces of the bottom portion and the front and rear wall portions are integrally joined to each other at both ends of the bottom portion folded in a substantially inverted V-shaped cross section at least at the upper part of the folding height range of the substantially inverted V shaped cross section. The cooking bag for a microwave oven according to claim 2, wherein the bottom portion is formed so as to be curved into a substantially boat bottom shape. 4. A synthetic resin film as a main constituent material is a laminated film having a heat-sealable resin layer on the inner surface side of a bag of a base material layer made of a resin film having heat resistance, and the paper material on the upper part of the bag is The cooking bag for a microwave oven according to any one of claims 1 to 3, which is made of a paper made from long-fiber pulp and is joined by a heat fusion means to form a bag.