JP2011148504A - Container for microwave oven - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a container for a microwave oven which is capable of allowing a food to be safely heated in a microwave oven after the container is once opened and food material is placed therein. <P>SOLUTION: The container for the microwave oven in which an opening portion is formed by opening/closing a zipper provided on the inner side of a top end, includes: a steam-passing portion in which a front member and a back member are provided to be peelable from each other; and a fold-in portion in which the back member is provided to be folded back from the steam-passing portion to the bottom side, at a part of a side seal portion on the bottom side from the zipper, wherein the fold-in portion is expanded to lift the steam-passing portion, and at the same time, the steam-passing portion is peeled to form a steam hole when steam is generated inside the container, when the sealed opening is heated, steam is generated in the container, and the internal pressure reaches or exceeds apredetermined value. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  TECHNICAL FIELD The present invention relates to a microwave oven container for introducing food into the interior and cooking with a seasoning liquid in a microwave oven.

  Conventionally, so-called retort foods in which foods contained in packaging bags such as pouches are heated and sterilized in a retort kettle are widely distributed and used. Since the retort food is sealed by the packaging bag, if it is to be heated as it is in the microwave oven, the packaging bag may expand and burst due to water vapor generated from the food.

  In order to solve this problem, there has been proposed a packaging bag in which the heat-resistant nonwoven fabric for escaping the above-mentioned water vapor is folded in two and attached to the inside of one side of the packaging bag (for example, patent document) 1). When heating retort food using this packaging bag in a microwave oven, cut off the end side where the non-woven fabric is attached, open the end on the non-woven fabric side, and then heat the food in the microwave oven together with the packaging bag To do.

  However, since the open end of the packaging bag proposed in Patent Document 1 is covered with a nonwoven fabric or the like, the retort food packaging bag filled with sauce or seasoning liquid is opened once and the ingredients are added. After that, it is not possible to heat the sauce and ingredients together with a microwave oven.

  If a well-known zipper that can be opened and closed is provided in the opening, it is possible to seal the packaging bag again by adding food, but the opening with the zipper closed is poorly breathable and is heated in a microwave oven In this case, the risk of the above-mentioned explosion becomes a problem.

  For this reason, it is sealed during normal storage and transportation, but a mechanism as a pressure valve that avoids the risk of steaming and bursting when the internal water vapor pressure rises due to heating in a microwave oven is provided on the packaging container. Various structures provided in part have been proposed.

Patent Document 2 discloses a food cooking bag characterized in that a pressure valve element that forms a pressure valve when sealed is printed on one open side of a bag that has three sides sealed. A body has been proposed, and Patent Document 3 proposes forming the pressure valve by applying a release agent.
However, in the cooking bag described in Patent Document 2 and Patent Document 3, the risk of leakage of contents from the steamed part to the outside when the internal water vapor pressure rises due to heating in the microwave oven is removed. Was difficult.

For this purpose, Patent Document 4 and Patent Document 5 have proposed packaging containers in which the position and shape of the steaming section and the chuck mechanism are devised in the form of a standing pouch. A packaging container provided with is proposed in Patent Document 6.
However, even with the above-described method, it has been difficult to easily remove the risk that the contents leak to the outside from the steamed portion when the internal water vapor pressure increases due to heating in the microwave oven.

Japanese Patent Laid-Open No. 8-80978 JP-A-8-228697 Japanese Patent Laid-Open No. 9-40030 Japanese Patent Laid-Open No. 11-189278 Japanese Patent No. 3802205 JP 2009-166853 A

  This invention is made | formed in view of the said situation, and it aims at providing the container for microwave ovens which can be heated with a microwave oven safely after opening once and throwing in foodstuffs.

  The container for the microwave oven of the present invention uses the vapor pressure of water vapor generated inside the container when heated in the microwave oven, releases water vapor to the outside of the container without causing the container to rupture, and is formed on one side of the container. It is a container for a microwave oven having a structure that uses the expansion of the part to push up the position of the steaming part for water vapor release to prevent leakage of the content food.

  According to the first aspect of the present invention, the side and bottom end portions of the front member and the rear member are formed to be sealed, and an opening is formed by opening and closing the chuck provided on the inner surface of the top end portion. A microwave oven container, a steaming portion provided in a state where the front member and the back member are peelable on a part of the side seal portion on the bottom side from the chuck, and the steaming portion. The bottom side is provided with a folded portion provided by folding the back member, heated when the opening is sealed, water vapor is generated inside the container and the internal pressure becomes a predetermined value or more, The microwave oven container is characterized in that the folding portion expands to raise the steaming portion, and at the same time, the steaming portion peels to form a steam hole.

  The invention according to claim 2 of the present invention is the microwave oven container according to claim 1, wherein the vapor passing portion is an unsealed portion provided in the side seal portion.

  The invention according to claim 3 of the present invention is the microwave oven container according to claim 1, wherein the steaming part is a weak seal part provided in the side seal part with a reduced number of seals. is there.

  The invention according to claim 4 of the present invention is the microwave oven container according to claim 1, wherein the vapor passing portion is a weak seal portion provided by inserting an easy peel tape into the side seal portion. .

  The invention according to claim 5 of the present invention is the container for microwave oven according to claim 1, wherein the vapor passing portion is a deformed seal portion of a stress concentration type provided on the side seal.

  The invention according to claim 6 of the present invention is the microwave oven according to any one of claims 1 to 5, wherein the front member and the back member are formed of a laminated film of two or more layers including a sealant and a base material. Container.

  According to the seventh aspect of the present invention, when the length between the top and bottom of the container is L, the position of the chuck from the top end is within 1/3 L, and the length of the folding part is from 5 mm to the folding part. Between the distance of the top end, the distance of the folding part from the chuck is within 1 / 2L, the steaming part is 1mm to 10mm in length and is provided at the position of the side seal part between the folding part and the chuck It is the container for microwave ovens of any one of Claim 1 to 6 characterized by the above-mentioned.

According to the microwave oven container of the first aspect of the present invention, the three ends of the side and bottom of the front member and the back member are formed to be sealed, and the chuck provided on the inner surface of the top end is opened and closed. Is a container for a microwave oven in which an opening is formed, and a steaming part provided in a state in which the front member and the rear member are peelable to a part of the side seal part on the bottom side from the chuck, A folding portion provided by folding the back member on the bottom side from the steaming portion, and heated in a state where the opening is sealed, and water vapor is generated inside the container so that the internal pressure is a predetermined value. When the above is reached, the folding portion expands and lifts the steaming portion, and at the same time, the steaming portion is peeled off to form a vapor hole, so that the vapor pressure of water vapor generated inside the container during heating in the microwave oven is reduced. Utilize container rupture Water vapor is released to the outside of the container without causing it, and the expansion of the folding part formed on one side of the container is used to push up the position of the steaming part for water vapor release and prevent leakage of the contents food from the steam hole I can do it.
Therefore, according to this invention, after opening from the chuck | zipper part of a top end part once and putting a seasoning, a foodstuff, etc., the container for microwave ovens which can be heated safely with a microwave oven can be provided.

  According to the microwave oven container of claim 2 of the present invention, the inside of the container that is generated during heating in the microwave oven because the vapor passing portion is an unsealed portion provided in the side seal portion and thus has no airtightness. It can safely handle sudden pressure increases. It is particularly suitable for heating solid foods such as potatoes that do not require airtightness or watertightness.

  According to the microwave oven container of the third aspect of the present invention, since the steaming part is a weak seal part provided by reducing the number of times of sealing in the side seal part, a specially shaped heat seal bar is used. Or, it is possible to form the steaming part without requiring an additional material such as an easy peel tape.

  According to the microwave oven container of claim 4 of the present invention, the vapor passing portion is a weak seal portion provided by inserting an easy peel tape into the side seal portion, so that normally there is air tightness and water tightness. However, it is possible to respond sensitively to an increase in pressure inside the container that occurs during heating in a microwave oven. Furthermore, since the selection range of sealant and heat seal conditions is expanded, there is also an advantage that manufacturing stability is excellent.

  According to the microwave oven container of the fifth aspect of the present invention, the vapor passage portion is a stress-concentrated shaped atypical seal portion provided on the side seal, thereby increasing the pressure inside the container during microwave heating. It is possible to prevent the generation of steam holes outside the steaming section by sensitively starting the stripping of the steaming section at a predetermined position. As a result, it is possible to more reliably perform cooking by microwave heating safely without causing leakage of contents or jetting of steam at unexpected parts.

  According to the microwave oven container of claim 6 of the present invention, the front member and the rear member are made of a laminated film of two or more layers including a sealant and a base material, and the sealant layers of the front and back members are overlapped with each other by a common member. There is an advantage that the container can be formed by heat sealing and can be easily manufactured by using a member in which a base material having heat resistance and contents protection as a cooking container is laminated.

According to the microwave oven container of claim 7 of the present invention, when the length between the top and the bottom of the container is L, the position of the chuck from the top end is within 1/3 L, and the length of the folding portion Is between 5mm and the distance between the folding part and the top end, the distance from the chuck to the folding part is within 1 / 2L, and the steaming part has a top and bottom length of 1mm to 10mm. Is provided at the position of the side seal portion between, using the vapor pressure of the water vapor generated inside the container when heated in the microwave oven, to release the water vapor outside the container without causing the container to burst, and Using the expansion of the folding part formed on one side of the container, the position of the steaming part for releasing water vapor is pushed up to prevent leakage of the content food material from the steaming part.

The plane schematic of an example of the container for microwave ovens of this invention 1 is a schematic cross-sectional view of an example of a container for a microwave oven according to the present invention (cross-sectional view taken along line XX in FIG. 1). 1 is a schematic cross-sectional view of an example of a container for a microwave oven according to the present invention (a cross-sectional view taken along line YY in FIG. 1). Schematic cross-sectional view of an example of a container for a microwave oven of the present invention (schematic diagram during cooking in FIG. 3) Schematic appearance of an example of the microwave oven container of the present invention (during cooking) Sectional schematic diagram which shows an example of the main body film which comprises the container for microwave ovens of this invention Sectional schematic diagram which shows an example of a structure of the easy peel tape used for the container for microwave ovens of this invention Sectional schematic diagram which shows an example of the intermediate | middle layer which comprises the container for microwave ovens of this invention

Hereinafter, one embodiment of a container for a microwave oven of the present invention will be described with reference to the drawings of FIGS.
FIG. 1 is a schematic plan view of an example of a container for a microwave oven according to the present invention, in which a microwave oven container (1) is joined to a front part (2) using a front member (2A) and a front member (2A). It is comprised from the back surface part (3) using the back member (3A).
FIG. 2 is a schematic cross-sectional view taken along the line XX of FIG. 1, and is a view highlighting the characteristic portion of the microwave oven container of the present invention.

  As shown in FIG. 1, the microwave oven container (1) of the present invention is sealed on the three side ends of the side seal portion (11) and the bottom seal portion (5) of the front surface portion (2) and the back surface portion (3). It is a container for a microwave oven formed by opening and closing a chuck portion (6) provided on the inner surface of the top end portion (4) to open and close the contents food.

  A steaming section (not shown) in which the front member and the rear member are not sealed or can be peeled off at a part of the side seal portion (11) on the bottom seal portion (5) side from the chuck portion (6). 7) and a folding part (8) provided by folding the back member (3A) closer to the bottom seal (5) than the steaming part (7).

  With such a configuration, the container (1) is heated in a state where a food containing moisture is enclosed and the chuck portion (6) is sealed. When the water vapor is generated inside the container (1) by heating and the internal pressure becomes a predetermined value or more, the folding part (8) expands from the inside and lifts the steaming part (7) and simultaneously the steaming part (7). Exfoliates to form vapor holes. As a result, the contents of the foodstuff and the like can be discharged from the steaming section without causing leakage, and the pressure of excess water vapor can be dissipated to prevent the container from bursting and can be heated safely.

The front member (2A) used for the front surface part (2) of the microwave oven container of the present invention is formed of a sheet-like flexible film having heat sealability (hereinafter referred to as “main body film”). . Similarly, the back member (3A) is formed of a sheet-like flexible film having heat sealability.
Usually, the main body film uses a laminated film of two or more layers including a base material (9) having heat resistance and contents protection as a cooking container and a sealant (10) excellent in heat sealability.

FIG. 6 is a schematic cross-sectional view showing an example of a main body film constituting the microwave oven container of the present invention. In this case, from the outside of the container, a base material (9) having a printed layer (14) on the inner surface and a sealant (10) on the innermost side are laminated, and an intermediate layer (16) is adhesive on both sides in the middle. Laminated via layer (15).
The print layer (14) and the intermediate layer (16) are provided as necessary, and specific examples of the intermediate layer will be described later.

  As a material of the base material (9) constituting the main body film in the microwave oven container of the present invention, if it has necessary heat resistance and is generally used as a food packaging material heated in a microwave oven There is no particular limitation.

For example, polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), polyolefins such as polyethylene (PE) and polypropylene (PP), polyamides such as nylon-6 and nylon-66 Stretched or unstretched resin such as (PA), polycarbonate (PC), polyacrylonitrile (PAN), polyimide (PI), polyvinyl alcohol (PVA), polyvinylidene chloride (PVDC), ethylene-vinyl alcohol copolymer (EVOH) Any of a film, nylon 6 / metaxylylenediamine nylon 6 coextruded film, polypropylene / ethylene-vinyl alcohol copolymer coextruded film, and the like can be used.
Alternatively, a composite film obtained by laminating these two or more films may be used.

The thickness of the substrate (9) is preferably in the range of 10 to 50 μm, more preferably in the range of 10 to 30 μm, in consideration of workability.
For example, known additives such as an antistatic agent, an ultraviolet absorber, a plasticizer, a lubricant, and a coloring agent can be added to the base material (9), and they are appropriately added as necessary.
Further, the surface of the base material (9) can be subjected to surface modification such as corona discharge treatment or anchor coating treatment to improve the adhesion and printability with a sealant layer (10) to be described later.

Moreover, a printing layer (not shown) can be formed in the surface or back surface of a base material (9) as needed.
The printed layer can be formed on either the front or back side of the base material (9), but in the same way as when printing on a general plastic film bag, the base material is considered in consideration of the friction resistance and weather resistance of the ink. It is preferable to provide the inner surface of the container (9) by a gravure printing method or the like.

  In the container for the microwave oven of the present invention, the innermost sealant (10) constituting the main body film includes, for example, a low density polyethylene resin (LDPE), a medium density polyethylene resin (MDPE), a high density polyethylene resin (HDPE), Linear low density polyethylene resin (L-LDPE), polypropylene resin (PP), ethylene-propylene copolymer (EP), ethylene-α olefin copolymer, ethylene-acrylic acid copolymer (EAA), ethylene- Methacrylic acid copolymer (EMAA), ethylene-methyl acrylate copolymer (EMA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methyl methacrylate copolymer (EMMA), ionomer resin, ethylene- Resin such as vinyl acetate copolymer (EVA), or film formation of these resins The films can be used.

  Further, the thickness of the layer of the sealant (10) is preferably in the range of 20 to 100 μm, more preferably in the range of 30 to 70 μm, considering the sealing strength, physical properties, and workability.

Methods for laminating the outermost layer base material (9) and the innermost layer sealant (10) include, for example, a dry lamination method, an extrusion lamination method, and a sandwich lamination method using the extrusion lamination method. Can be used.

  As the adhesive used in the dry lamination method, generally, an adhesive for laminating such as polyurethane, polyacrylic, polyester, epoxy, polyvinyl acetate, cellulose, or the like can be used.

  In the microwave oven container of the present invention, when the substrate (9) and the sealant (10) alone cannot sufficiently function as the microwave oven container, the substrate (9) and the sealant (10) An intermediate layer (not shown) can be provided between the two.

  Examples of the functions include gas barrier properties, mechanical toughness, flex resistance, puncture resistance, impact resistance, wear resistance, cold resistance, heat resistance, chemical resistance, and the like. These functions required as (1) are achieved by providing an intermediate layer.

When the contents stored in the microwave oven container (1) according to the present invention require resistance to oxygen gas, water vapor, light, etc., long-term room temperature circulation, etc., the intermediate layer or the base material may include a gas barrier layer. May need to be provided.
In FIG. 8, the cross-sectional schematic diagram which shows an example of the intermediate | middle layer which comprises the container for microwave ovens of this invention was shown. Here, a vapor-deposited thin film layer (22) of an inorganic oxide is provided on the intermediate layer base material (20) via a primer layer (21), and further a gas barrier coating layer (23) is provided on the surface thereof. Yes.

  As the gas barrier layer for this purpose, a gas barrier film using a gas barrier resin or a gas barrier film provided with another gas barrier layer as illustrated in FIG. 8 on a resin film is used.

For example, ethylene-vinyl alcohol copolymer film (EVOH), polyvinyl alcohol film (PVA), ethylene-vinyl acetate copolymer (EVA) saponified film, polyethylene terephthalate (PET), polyamide (PA), polypropylene (PP) film coated with polyvinylidene chloride, inorganic oxide (silicon oxide, aluminum oxide, etc.) deposited thin film layer, or laminated film combining one or more of these films Can be used.
Among these, a gas barrier film provided with a deposited thin film layer of an inorganic oxide (such as silicon oxide or aluminum oxide) that can be heated in a microwave oven and can be easily disposed of is preferable. These gas barrier layers may be provided on the substrate instead of the intermediate layer.

  The chuck part (6) provided on the inner surface of the top end part (4) of the container for microwave oven of the present invention shown in FIGS. It is provided for heating by a range, and is formed by attaching engaging protrusions that engage with each other using a molded product of synthetic resin such as polypropylene resin.

  Usually, since it is attached to the inner surface (sealant surface) of the container by a heat seal method, when a polypropylene resin is used as the sealant (10) of the container, it is preferable to use a polypropylene resin also for the chuck part (6). The chuck portion (6) can be attached to the container in-line with the bag making by incorporating a dedicated attachment device into the bag making machine.

FIG. 3 is a schematic cross-sectional view taken along line YY of the microwave oven container of FIG. Here, a case where an easy peel tape (12) is used as the steaming part is shown. In the microwave oven container of the present invention, the steaming section (7) has a top and bottom length of 1 mm to 10 mm and a height between the chuck section (6) and the folding section (8) of the side seal section (11). The easy peel tape (12) is sandwiched between the sealant (10) of the front member (2A) and the back member (3A).

  When a force that separates the front member (2A) and the rear member (3A) acts on the steam passage section (7), the front sealant and the rear sealant joined together by the easy peel tape (12). And a steam hole for performing steam venting is formed on the front surface part (2) or the back surface part (3) side of the steaming part (7). FIG. 4 schematically shows a state at the time of forming the vapor hole corresponding to FIG. The internal pressure value required for forming the steam hole may be set to a predetermined value as appropriate.

The easy peel tape (12) is a tape that is easily peelable by the internal pressure of a gas such as water vapor generated by heating the microwave oven container (1), and is against the sealant (10) on the inner surface of the microwave oven container. A typical case is composed of two layers of an adhesive resin layer showing adhesiveness and an easily peelable resin layer showing easy peelability by an internal pressure of a gas such as water vapor generated by heating the container for microwave oven. Easy peel tape may be an easily peelable sealant.
The cross-sectional schematic diagram which shows an example of the structure of the simple easy peel tape used for the container for microwave ovens of this invention in FIG. 7 was given.

  As the above-mentioned adhesive resin layer exhibiting adhesion to the sealant (10), the heat-sealable adhesive thermoplastic resin constituting the inner surface sealant (10) of the main body film can be used as it is. A layer made of a propylene-based polymer (copolymer or terpolymer) called CPP or a linear low density polyethylene called LLDPE or LLD is preferably used. The thickness is often 20 to 150 μm.

  As the easily peelable resin layer exhibiting the above easy peelability, for example, a block polypropylene copolymer, a random polypropylene copolymer, an ethylene copolymer such as ethylene / vinyl acetate, and the like are preferably used. As the ethylene-based copolymer, a copolymer having an ethylene component content of 85 to 98% by weight is particularly desirable.

  Here, a typical example of the block polypropylene-based copolymer is a polypropylene-polyethylene block copolymer, and a typical example of the random polypropylene-based copolymer is a propylene-ethylene random copolymer.

  The lamination method of said adhesive resin layer and easily peelable resin layer is not specifically limited. For example, well-known methods such as a dry lamination method, an extrusion lamination method, and coextrusion may be mentioned.

In the microwave oven container of the present invention, the structure of the steaming section (7) is not limited to the case where the easy peel tape exemplified above is used.
For example, the steaming part (7) may be provided by leaving an unsealed part in the side seal part (11). When the contents are solids that do not require watertightness, this structure is preferable because it allows the vapor to pass through with a simple structure, but in order to obtain an increase in internal pressure to inflate the container by internal pressure during heating. The length of the steaming part (7) is preferably 1 mm or more and 10 mm or less.

Furthermore, the weak seal part provided by reducing the frequency | count of a seal | sticker may be sufficient as a weak seal part to the extent that a steaming part (7) peels to a side seal part (11) with a vapor pressure.
In this case, a state having water tightness and air tightness can be realized by reducing the number of heat seals in a part of the region without using another member such as an easy peel tape (12). Regardless, it can be safely transported and stored after closing the chuck.

Further, the object of the present invention can also be achieved by the fact that the steaming part (7) is a stress-concentrated shaped atypical seal part provided in the side seal part.
When the heat seal region of the sealant (10) of the front surface portion (2) and the back surface portion (3) is peeled by applying stress in the peel direction in the steaming portion (7), the shape of the heat seal region is changed with respect to the stress direction. For example, by forming a triangular shape instead of a right angle, stress can be concentrated on the apex portion of the triangle so that even a small stress can be easily peeled off at a specific location.
The shape of the atypical seal region is not limited to a triangle, and the corrugated and elliptical regions may be combined singly or using a plurality of shapes.

In the microwave oven container (1) of the present invention, as shown in FIG. 2, the folding part (8) is formed so that a part of the back surface part (3) protrudes outside the container.
The back surface portion (3) is formed from a back surface member (3A) made of a main body film. The main body film of the back surface portion (3) is folded back substantially in parallel with the upper and lower end portions at an intermediate position between the top end portion (4) and the bottom seal (5) of the microwave oven container (1). A folded portion (8) having a protruding portion protruding toward the end (4) side is formed.

  The folding part (8) has a function of increasing the volume of the microwave oven container (1) and raising the top end (4) side during heating in the microwave oven. The folding part (8) is located on the top part (4) side of the microwave container (1), preferably the distance of the folding part from the chuck is within ½ of the height L of the microwave container (1). It is possible to make the top part (4) side stand up more favorably during heating when it is provided at the position. For this purpose, the length of the folding part (8) is preferably between 5 mm and the distance between the folding part and the top end.

  The rear member (3A) and front member (2A) of the main body film on which the above-mentioned respective parts are formed are arranged so that the sealants (10) face each other, and the three end portions excluding the top end portion (4) Are joined together by heat fusion. At the same time, heat is applied to the easy peel tape (12) to form the steaming part (7).

At this time, when the length between the top and the bottom of the container (1) is L, the position LC of the chuck (6) from the top end is within 1 / 3L, and the length of the folding part (8) is from 5 mm. Between the folding part and the top end part, the distance LP of the folding part (8) from the chuck (6) is within 1 / 2L, and the steaming part (7) is the folding part with a length of the top and bottom LS from 1 mm to 10 mm. (8) is provided at the position of the side seal portion between the chuck (6). After the contents F are filled from the chuck portion (6) and the chuck portion is fitted and sealed, the contents are A sealed microwave oven container is completed.

Next, the operation when using the microwave oven container (1) will be described.
2 and 3 are schematic cross-sectional views of the state of the contents of the microwave oven container (1) not sealed, and FIG. 4 is a schematic cross-sectional view of the contents sealed and heated in the microwave oven. . FIG. 5 is a schematic external view of the state in which the contents are similarly sealed and heated in a microwave oven.

  First, when the user disengages the engaging protrusion of the chuck portion (6) and widens the top end portion (4), the top end end (4) is opened, and the food material as the contents can be put in. When the top end (4) is sealed, the above operation is performed after the container is cut between the top end and the chuck (6).

The user puts food F such as potato and carrot and seasonings into the inside of the microwave oven container (1) from the top end (4), and closes and seals the chuck portion (6). At this time, the folding portion (8) is developed by the introduction of the food F, the volume of the container (1) is increased, and the region on the top end (4) side from the folding portion (8) rises upward. .

  Then, a user installs the container (1) for microwave ovens with which foodstuff F, seasonings, etc. were enclosed in a microwave oven, and heats it. Ingredient F is cooked with seasonings and the like. At this time, a steaming space in which high-temperature water vapor generated by heating stays is formed inside the container.

  Since the top end part (4) is sealed by the chuck part (6), the amount of water vapor exceeding the volume of the container (1) moves toward the steaming part (7). As a result, when the internal pressure of the steaming part (7) increases to a predetermined value or more, a force that separates the front surface part (2) and the back surface part (3) acts on the steaming part (7). Then, the easy peel tape (12) in the region of the steaming section (7) is separated from the sealant (10) of the front member (2A) or the back member (3A), and a steam hole is formed as shown in FIG. .

At the same time, the main body film folded into the back surface (3) of the container (1) spreads due to the internal pressure of water vapor to increase the volume inside the container and lift the back surface (3) on the top side of the container (1). It swells as shown in FIG.
As a result, the amount of water vapor exceeding the volume of the container (1) diverges appropriately from the vapor hole raised to a high position, and the container (1) is prevented from bursting without the contents leaking to the outside. Safe cooking is possible.
After the cooking is completed, the user again releases the engagement of the chuck portion (6), opens the top end portion (4), and arranges the food F, seasoning liquid, and the like in the container.

  In this microwave oven container, since the folding part (8) is provided in the back surface part (3), when the foodstuff F is thrown in, the folding part (8) is expanded to expand the microwave oven container (1). The internal volume increases and a steaming space is secured. Therefore, uniform heating is performed inside the microwave oven container, and cooking can be performed satisfactorily.

  In the above embodiment, the state in which the top end (4) is not sealed is illustrated, but it is stored for a relatively long time in a state where foodstuffs such as seasonings are enclosed, and the top seal is immediately before heating in the microwave oven. Of course, there may be a case where an opening is formed by cutting between the chuck portions. In such a case, it is possible to improve usability by heat-sealing the top portion by a known method and by providing a notch for opening between the top seal and the chuck portion.

<Example 1>
A main body film was prepared by laminating a polypropylene film (thickness 30 μm) as a sealant on one side of a biaxially stretched polyethylene terephthalate film (thickness 12 μm) as a substrate. As an adhesive for dry lamination, Dainippon Ink and Chemicals LX703VL was used and the coating amount was 4 g / m ² .
Using this main body film, a film of the back member (3A) provided with a folding part as shown in FIG. The length (a) of the folding part shown in FIG. 2 was 50 mm.

  The rear member (3A) and front member (2A) of the main body film on which the above-mentioned respective parts are formed are arranged so that the sealants (10) face each other, and the three end portions excluding the top end portion (4) Were joined together by heat fusion. At the same time, an easy peel tape (12) mainly made of polyethylene with a width of 10 mm is sandwiched between the steaming part (7) in FIG. 2, and the chuck part (6) is attached to the top end part by heat sealing. The bottom and side were sealed with a bag making machine to produce a microwave oven container as shown in FIGS.

At this time, the length L between the top and bottom of the container is 250 mm, the width W of the container is 200 mm, the position LC of the chuck (6) from the top end is 30 mm, the length of the folding part (8) is 50 mm, the chuck The distance LP of the folding part (8) from (6) is 100 mm, the top and bottom LS of the steaming part (7) is 10 mm long, and the side seal part is 10 mm from the folding part (8) and the chuck (6). It was made to be provided in the position.
The microwave container thus prepared is filled with the contents F made of food and seasoning liquid from the chuck part (6), and then the chuck part is fitted and sealed, so that the contents are sealed. A container for a range was obtained.

  The microwave container filled with the contents was set in a microwave oven with the back side down and cooked by heating in the microwave oven. By heating, the container expanded and eventually the top end was lifted, and water vapor spouted from the steaming part near the end, and the appearance of the container was as shown in FIG.

  The rise of the internal pressure which leads to the rupture is avoided by the steam hole from which the steam is ejected, and the steam passage portion where the steam hole is formed is lifted by the internal pressure and is located at a position higher than the content F. The cooking was completed safely with no leakage from After completion, the cooked food and the like were taken out by opening the chuck portion from the top end of the container, and were cooked uniformly without heating unevenness.

  The container for the microwave oven according to the present invention can be cooked without soiling the pot because it can not only warm the food but also enclose the favorite ingredients together with the seasoning etc. and cook it in the microwave. It can save water for cleaning and cleaning. Moreover, this container can be applied to the case where it is necessary to heat not only food but also various materials including moisture in a microwave oven.

DESCRIPTION OF SYMBOLS 1 ... Microwave oven container 2 ... Front part 3 ... Back part 2A ... Front member 3A ... Back member 4 ... Top end part 5 ... Bottom seal part 6 ... Chuck part 7 ... Steaming part 8 ... Folding part a ... Folding part length DESCRIPTION OF SYMBOLS 9 ... Base material 10 ... Sealant 11 ... Side seal part 12 ... Easy peel tape 13 ... Ejected water vapor | steam 14 ... Printing layer 15 ... Adhesive layer 16 ... Intermediate | middle layer 17 ... Adhesive resin layer 18 ... Easily peelable resin layer 19 ... Intermediate | middle Layer 20 ... Intermediate layer substrate 21 ... Primer layer 22 ... Deposited thin film layer 23 of inorganic oxide ... Gas barrier coating layer W ... Outside dimension width WS of microwave oven container ... Width L of side seal part ... Outer dimension height LP ... Distance LC from chuck part position to folding part position ... Distance LS from top end part to chuck part position ... Fusion length F ... Contents

Claims (7)

The microwave oven container is formed by sealing the three sides of the front member and the back member on the side and bottom, and an opening is formed by opening and closing a chuck provided on the inner surface of the top end.
A steaming portion provided in a state where the front member and the back member can be peeled off at a part of the side seal portion on the bottom side from the chuck, and the back member is folded back to the bottom side from the steaming portion. Provided with a folding part,
When the opening is sealed and water vapor is generated inside the container and the internal pressure becomes a predetermined value or more, the folding portion expands to lift the vapor passage and at the same time the vapor vapor peels off And a steam hole is formed.   The container for a microwave oven according to claim 1, wherein the steaming part is an unsealed part provided in the side seal part.   The container for a microwave oven according to claim 1, wherein the steaming part is a weak seal part provided in the side seal part with a reduced number of times of sealing.   The container for microwave oven according to claim 1, wherein the steaming part is a weak seal part provided by inserting an easy peel tape into the side seal part.   The container for a microwave oven according to claim 1, wherein the vapor passing portion is a deformed seal portion having a stress-concentrated shape provided on the side seal.   The container for a microwave oven according to any one of claims 1 to 5, wherein the front member and the rear member are made of a laminated film of two or more layers including a sealant and a base material.   When the length between the top and the bottom of the container is L, the position of the chuck from the top end is within 1/3 L, the length of the folding part is 5 mm, and the distance between the folding part and the top end is from the chuck. The distance of the folding part is within 1 / 2L, and the steaming part has a top and bottom length of 1 mm to 10 mm and is provided at the position of the side seal part between the folding part and the chuck. The container for microwave ovens of any one of 6.

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