JP3309124B2 - Food packaging for microwave oven - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a food package for a microwave oven mainly for frozen foods which is heated by a microwave oven .

[0002]

2. Description of the Related Art A pouch for a microwave oven, in which cooked foods such as frozen foods are put inside and heated together with a bag during cooking, has been well known. In the case of this type of pouch, a packaging form such as a four-sided seal or a gasket is generally used.However, if cooking food is stored in the pouch and the opening is simply sealed, the pressure in the pouch is increased by heating. However, there is a disadvantage that the bag is broken when the height is increased, or the seal portion is peeled off. Therefore, a means for removing steam in the pouch is required. Further, in order to obtain a steaming effect by increasing the temperature in the pouch, it is necessary to not only release the pressure but also to maintain the internal pressure at a certain level. Therefore, for example, in Japanese Unexamined Patent Publication No. Sho 62-94117 and Japanese Patent Publication No. Sho 62-54707, a small hole is provided in a part of a non-breathable packaging material, and the inside of the container is adjusted to a predetermined internal pressure by the small hole. Something like that has been proposed. However, in the method of providing such small holes, it is practically difficult to freely adjust to various kinds of contents.

[0003] Therefore, adjustment of the internal pressure with a non-woven fabric having air permeability has been partially performed. In that case, a nonwoven fabric is provided in a band shape on a part of the non-breathable pouch, and the air permeability and area of the nonwoven fabric are adjusted according to the contents. Pouches using this type of nonwoven fabric are common as sterilization bags. For example, 51-1
JP-A-5682 and JP-B-59-31256 are mainly used for sterilization, and include a sheet containing a synthetic resin nonwoven fabric sheet or a porous film as a part of a pouch. The air-permeable member is configured to be thermally bonded.

[0004]

However, in a pouch in which a permeable member such as a non-woven fabric is thermally bonded to release pressure, the permeable member has no moisture-proof property, so that the pouch is used at the time of distribution, sale and the like. There is a problem in that the moisture of the cooked food inside radiates to the outside and the food is dried.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is possible to secure moisture proof of contents at the time of distribution, sale, and the like, while releasing steam inside at the time of cooking. To prevent the bag from breaking, etc., and to obtain the steaming effect by freely adjusting the internal pressure.
An object of the present invention is to provide a food package for a microwave oven .

[0006]

SUMMARY OF THE INVENTION A package for a microwave oven according to the present invention is made of a non-breathable wrapping material, and both ends of the wrapping material are overlapped so that the inner surfaces thereof are in contact with each other to form a back seal portion. A food package for a microwave oven in which cooked food is enclosed inside a pouch attached to the palms, wherein the packaging material is a laminate of a heat-resistant synthetic resin film including a uniaxially stretched film, and the pouch is a uniaxially stretched film. The stretch direction is formed so as to coincide with the longitudinal direction of the back seal portion, and a non-woven fabric having air permeability is heat-bonded to both sides of the non-woven fabric in parallel with the back seal portion on the inner surface of the pouch where the back seal portion is provided. For packaging
Is characterized in that a notch for tearing the packaging material is provided near the inner side of the back seal portion and outside the thermal bonding portion with the nonwoven fabric.

[0007]

[Function] At the time of distribution and sale, since the entire surface of the air-permeable non-woven fabric is covered with a non-breathable wrapping material which is hermetically sealed with a palm joint, cooked food and the like stored inside can be taken out of the pouch. divergence of water is prevented, and on the other hand, at the time of cooking such as by microwave, back from the point of the cut
By tearing the packaging material along the seal portion, the internal vapor is released to the outside through the nonwoven fabric having air permeability, and thereby the internal pressure is adjusted. At that time, the internal pressure of the pouch is
It can be adjusted freely by changing the air permeability and area of the nonwoven fabric.

[0008]

Embodiments will be described below with reference to the drawings.

FIG. 1 is a perspective view of a pouch according to one embodiment of the present invention, FIG. 2 is a cross-sectional view of the pouch, and FIG. 3 is a layer configuration diagram of a packaging sheet constituting the pouch.

In this embodiment, the pouch 1 comprises a polyester film 2, a uniaxially oriented polypropylene film 3
And a non-breathable packaging material sheet 6 composed of a laminate obtained by bonding the unstretched polypropylene film 4 via a dry laminating adhesive 5 into a tubular shape with the face of the unstretched polypropylene film 4 inside. The pouches 1 are overlapped with each other and heat-sealed (attached to the palm), and a belt-shaped polypropylene-based nonwoven fabric 7 is heat-sealed on the inner surface of the pouch 1 at the overlapped portion. Here, when forming the pouch 1, the stretching direction of the uniaxially stretched polypropylene film 3 of the packaging material sheet 6 is made to coincide with the longitudinal direction (tearing direction) of the pouch 1. Further, the width of the nonwoven fabric 7 to be heat-sealed to the inner surface of the pouch 1 is set to be larger than the width of the overlapping portion of the packaging sheets 6. In addition, a heat seal portion (back seal portion) 8 between the packaging material sheets 6 is set on the edge side of the overlapped portion, and the seal portions 9 and 9 between the packaging material sheet 6 and the nonwoven fabric 7 are
An edge of the nonwoven fabric 7 is provided in parallel with the back seal portion 8. The nonwoven fabric 7 used here has an air permeability of 10
~ 90 (sec / 100cc), specifically, Asahi Kasei,
The product name “LUXER” —product number P1060ZZ is preferred.

As shown in FIG. 1, the wrapping material sheet 6 has an edge at a position slightly inside the back seal portion 8 and a top edge (or a bottom edge) of the pouch 1 in a state of being formed into the pouch 1. Notch (V notch) 1
0 and 11 are provided.

The pouch 1 is heat-sealed along the bottom edge (upper part in FIG. 1), stores cooked food inside, and heat-seales the opening (lower part in FIG. 1) to obtain a product.

According to the pouch 1, since the whole surface of the non-permeable air-permeable nonwoven fabric 7 is covered with the non-air-permeable packaging material sheet 6 at the time of distribution, sale and the like, the cooked food stored inside can be used. The diffusion of water is prevented, and moisture proofness is secured.

When the pouch 1 is cooked, the packaging material sheet 6 is torn along the back seal portion 8 from the location of the cut 10 provided slightly inside the back seal portion 8 and the nonwoven fabric 7 is applied to the surface. After exposing, put the whole pouch 1 in the microwave. Then, steam is generated from the cooked food during heating and cooking, and an internal pressure is applied to the pouch 1, and the internal pressure is adjusted by the air permeability of the nonwoven fabric 7, so that the cooking temperature is kept high (100 to 105 ° C.) The cooked food is heated uniformly in a steamed state. And after cooking, pouch 1
When the food is taken out from the inside, the packaging material sheets 6 on the front surface and the back surface are opened by tearing each of the packaging material sheets 6 from the notch 11 provided at the edge near one side. At that time, since the tearing direction is configured to match the stretching direction of the uniaxially stretched polypropylene film 3, the tearing of the packaging material sheet 6 can be performed easily and neatly. Here, as the cooked food to be put in the pouch 1, for example, grilled rice balls, gyoza, omelet, corn, sweet potato, and the like are preferable.

FIG. 4 is a perspective view of a pouch according to another embodiment of the present invention.

In this embodiment, the pouch 1 'is formed by a so-called gusset bag having both right and left side edges folded inward.
Is formed. Other configurations and operations are not essentially different from the previous embodiment. Therefore, the same reference numerals are given to the parts common to the previous embodiment, and the detailed description will be omitted. According to this embodiment, the same effects as those of the previous embodiment can be obtained.

In each of the above embodiments, the packaging material sheet is described as having a laminated structure of polyester film / DL / uniaxially stretched polypropylene film / DL / unstretched polypropylene film. It may be constituted by using uniaxially stretched polyethylene instead of the uniaxially stretched polypropylene film.

[0018]

Since the present invention is constituted as described above, the cooked food, which is the contents of the pouch, is protected at the time of distribution, sale, etc., and the diffusion of moisture to the outside can be prevented. On the other hand, during cooking, the steam generated from the cooked food stored in the pouch is released to the outside through the non-woven fabric, so that the bag is not broken, and the internal pressure is adjusted to a predetermined temperature. It is possible to realize uniform and shorter heating by keeping the temperature and to obtain the steaming effect.

[Brief description of the drawings]

FIG. 1 is a perspective view of a pouch according to an embodiment of the present invention.

FIG. 2 is a sectional view of a pouch according to one embodiment of the present invention.

FIG. 3 is a layer configuration diagram of a packaging material sheet constituting the pouch according to one embodiment of the present invention.

FIG. 4 is a perspective view of a pouch according to another embodiment of the present invention.

[Explanation of symbols]

 1, 1 'pouch 6 packaging sheet 7 non-woven fabric 8 back seal 9 seal

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B65D 33/00-33/01 B65D 33/25 B65D 81/26 B65D 81/34

Claims (1)

(57) [Claims] 1. A microwave oven in which cooked food is enclosed in a pouch that is made of a non-breathable wrapping material and has a back seal portion in which both ends of the wrapping material are overlapped so that their inner surfaces are in contact with each other to form a back seal portion. A food packaging body, wherein the packaging material is a laminate of a heat-resistant synthetic resin film including a uniaxially stretched film, and in the pouch, a stretching direction of the uniaxially stretched film matches a longitudinal direction of the back seal portion. A nonwoven fabric having air permeability is heat-bonded to the inner surface of the pouch at the portion where the back seal portion is provided in parallel with the back seal portion at both side edges of the nonwoven fabric, and the backing material is attached to the packaging material. A food package for a microwave oven, characterized in that a notch for tearing a packaging material is provided near an inner side of a seal portion and outside of a heat bonding portion with the nonwoven fabric.