JPH0771971B2 - Independent packaging bag - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a packaging bag that accommodates foods and the like and can be cooked in a microwave oven, and particularly to a packaging bag that can stand on its own during cooking.

[Conventional technology and its problems]

In recent years, the number of cooked or semi-cooked foods that can be served on the table by simply reheating them in a microwave oven or the like is increasing. In order to prevent deterioration of the taste and quality of such foods, light and air, Sealing and packaging are generally performed with a packaging material including a metal thin film layer such as an aluminum foil having an excellent barrier property against moisture.

However, since the metal thin film layer reflects microwaves, even if the packaging form as described above is put into the microwave oven as it is, the contents cannot be heated,
In addition, the microwave oven itself may be damaged, so the package is opened, the contents are taken out, transferred to another container, and heated. However, even in that case, it is necessary to further wrap the container with a wrap film, which is very troublesome.

Therefore, in order to save the labor as described above, the present inventors have already proposed a packaging bag in which the metal thin film layer portion can be removed and thus can be cooked as it is.

However, in such a bag, there is a risk that the pressure inside the bag will rise and burst due to overheating during cooking, and it is necessary to provide an opening in the bag to prevent it, but in a flat bag the contents are May be omitted.

Therefore, an object of the present invention is to provide a self-supporting bag in which contents are not spilled even if an opening is provided.

[Means for achieving the purpose]

In order to achieve the above-mentioned object, the packaging bag of the present invention has an easily peelable joining layer composed of an adhesive layer and a resin layer having a weaker adhesive strength than the adhesive layer on the outer surface of a synthetic resin substrate whose inner surface can be heat-sealed. Side sheet in which a gas barrier layer including a metal thin film layer is laminated, a two-fold synthetic resin inner bottom sheet having outer surfaces heat-weldable and notched at both ends, and an outer surface heat-fusingable metal thin film The heat-melting sheet comprises a double-folded outer bottom sheet having a cutout at both ends including a layer, and the outer bottom sheet is superposed on the inner bottom sheet folded in two so that the cutouts of both sheets coincide with each other. It is inserted into the lower part of the side surface sheet with the wearable inner surfaces facing each other, and the lower edge of the inner bottom surface sheet is positioned above the lower edge of the side surface sheet,
In addition, the lower edge of the outer bottom sheet is made to substantially coincide with the lower edge of the side sheet, the side edges of the side sheet are heat-sealed, and the side edges and lower edges of the inner bottom sheet and the inner surface of the side sheet are heat-sealed. The lower edge of the outer bottom sheet and the inner surface of the side sheet are heat-sealed.

[Action]

Since the gas barrier layer including the metal thin film layer is laminated on the synthetic resin substrate through the easy peeling bonding layer having low adhesive strength, the bag formed of the above-mentioned sheet can be easily peeled by hand, and The outer bottom sheet can also be easily removed by cutting off the lower end of the bag, and when these are removed, a bag made of a synthetic resin base remains, which transmits microwaves, so that it can be cooked in the microwave as it is. can do.

〔Example〕

First, the side sheet, the inner bottom sheet, and the outer bottom sheet that form the packaging bag will be described.

As shown in FIG. 1, the side sheet 1 is made of a synthetic resin base material 2.
Via a heat-sealing layer 3 on the inner surface and an easily peelable joining layer composed of a resin layer 4 and an adhesive layer 5 having relatively weak adhesive strength on the outer surface,
A metal thin film layer 6 such as a metal foil or a metal vapor deposition film as a gas barrier layer is laminated. A surface protective layer 7 is preferably provided on the outer surface of the metal thin film layer 6. The layer 7 is formed by coating a synthetic resin or laminating a synthetic resin film. In addition, a printed layer may be provided on the outer surface of the metal thin film layer 6.

The base material 2 includes polyester, nylon (trade name),
Polypropylene or the like is preferable, and either a simple substance or a composite thereof may be used. Further, as the heat-sealing layer 3, polyolefin, ethylene-vinyl acetate copolymer, or the like is used. The layer 3 can be omitted if the base material 2 itself has a heat fusion property.

The resin layer 4 has relatively weak adhesive strength, such as vinyl resin, urethane resin, acrylic resin or polyamide resin,
It is composed of a single substance or a mixture of silicone resin, etc., and is formed by a part coat of this resin. One example of the pattern is as shown in FIG. 3 (a), (b) and (c). The uncoated portion should have a dot, linear, or grid pattern. The resin layer 4 may be provided on the metal thin film layer 6 contrary to FIG. In some cases, it can be applied over the entire surface.

In this manner, by mixing the adhesive layer 5 and the resin layer 4 having a weaker adhesive strength than that, the adhesive strength of the joint surface, which cannot be easily peeled off by hand only with a normal adhesive layer, is weakened, Can be adjusted so that it can be easily peeled off.

Further, by selecting the coating density of the resin layer 4 according to the type of adhesive, it is possible to easily control the adhesive strength to such an extent that it can be easily peeled by hand.

As shown in FIG. 2, a reinforcing layer 6 ′ can be provided on the inner surface of the metal thin film layer 6. The reinforcing layer 6'is made of polyester, polypropylene, nylon, epoxy resin or the like, and prevents corrosion of the metal thin film layer during retort treatment and at the same time increases the thickness as a gas barrier layer and facilitates peeling. Also useful for.

Next, as shown in FIG. 4, the inner bottom sheet 10 is formed by laminating a synthetic resin base material 11 and a heat fusion layer 12. The base material 11 is made of a simple substance or a composite of polyester, nylon, polypropylene, ethylene-vinyl alcohol copolymer, polyvinylidene chloride, or the like. Also, layer 12
Is selected from polyolefins, ethylene-vinyl acetate copolymers, and the like, which have good heat fusion properties with the heat fusion layer 3 of the side sheet 1. If the base material 11 has thermal adhesiveness, this layer
12 may be omitted.

The outer bottom sheet 20 is, as shown in FIG. 5, a metal thin film layer 21 such as a metal foil or a metal vapor-deposited film provided with a heat fusion layer 22. It is preferable to provide the protective layer 23 on the outer surface of the layer 21. Further, the heat-sealing layer 22 may be any material that can be heat-sealed to the heat-sealing layer 3 of the side sheet, and polyolefin, ethylene-vinyl acetate copolymer or the like is used.

6 and 7 show an example of forming a packaging bag using the side sheet 1, the inner bottom sheet 10 and the outer bottom sheet 20 as described above.

First, two side sheets 1 and the heat-sealing layer 3 as the inner surface,
The inner bottom sheet 10 is folded in two and inserted between them. At this time, the notches 13 are formed in both ends of the sheet 10 so that the heat-sealing layer 12 is the outer surface. Further, the lower edge of the sheet 10 is located above the lower edge of the sheet 1. Further, the outer bottom sheet 20 is also folded in two with the heat-sealing layer 22 as the outer surface, and the notches 24 are formed at both ends. This notch 24 is
The notch 13 of the inner sheet is provided at the corresponding position. The sheet 20 is inserted into the lower side of the sheet 10, and the lower edge of the sheet 20 extends below the lower edge of the sheet 10 so as to substantially coincide with the lower edge of the side sheet 1.

Then, the peripheral portion of the sheet 1 and the portion corresponding to the lower edge of the sheet 10 are heat-sealed to form the heat-sealing portions 8 and 9 as shown by a chain line in FIG. 7, whereby a bag is completed. At this time, at the bottom sheet 10, 20, both side edges of the inner bottom sheet 10 and the inner surface of the side sheet 1 are fused, but the notch 13
The inner surfaces of the side sheets 1 are directly fused to each other at points 24 and 24. The lower edge of the inner bottom sheet 10 and the lower edge of the outer bottom sheet 20 are fused to the side sheet 1.

The contents are stored in such a bag, and as shown in FIG.
When the opening 9'is heat-sealed, the package is completed.

As shown in FIG. 8, half-cuts 31 and 32 may be preliminarily provided at the lower corners of such a bag or slightly above it. This half-cut is a cut that reaches at least the base material 2 of the sheet 1 and is the metal thin film layer 6 of the bag.
Is a clue to peeling. That is, when the metal thin film layer 6 and the substrate 2 are slightly separated at the end face of the cut when bent so as to expand along the cut, the metal thin film layer 6 can be peeled off by pinching the portion. .

In order to remove the metal thin film layer 6 from both sides of the bag, one half cut 31, 32 is provided on the opposite side of the bag.

In order to use this bag for cooking, first, the corner portion of the bag is bent along the half-cut 31 shown in FIG. 8, and the metal thin film layer 6 is separated from the base material 2 at the end face of the cut. ,
The metal thin film layer 6 can be pinched by hand. When the metal thin film layer 6 is pulled together with the surface protection layer 7 using that as a clue,
It is peeled from the base material 2. Similarly, when the metal thin film layer 6 is peeled off on the opposite surface of the bag, the bag made of the synthetic resin base material 2 remains. Then, as shown by the arrow 33 in FIG. 8, when the lower part of the heat sealing section 9 is cut, the outer bottom sheet 20 is fused to the side sheet 1 only at the lower edge portion thereof, and the fusion portion Since the outermost bottom sheet is removed by cutting off, the self-supporting synthetic resin bag as shown in FIG. 9 is formed. Put this bag in the microwave and cook. At this time, if the upper end of the self-standing bag is cut off and an opening is provided, the bag does not burst even if the contents expand due to heating.

When the reinforcing layer 6'is provided, it may be peeled by the above procedure together with the metal thin film layer 6.

Contrary to the above, before peeling off the metal thin film layer 3, after cutting the lower part of the heat-sealing portion 9 (the portion corresponding to the arrow 33 in FIG. 8), bending at the half cut 32, the same as above. Alternatively, the metal thin film layer 6 may be peeled off.

〔effect〕

As described above, the packaging bag of the present invention is composed of a laminate of a synthetic resin base material and a metal thin film layer, is tough and has excellent barrier properties, and can withstand ordinary temperature distribution, long-term storage, etc. Moreover, since the quality of the contents can be prevented and the metal thin film layer can be peeled off to make it self-supporting,
It can be cooked in a microwave oven, and if an opening is provided during cooking, it is possible to prevent the bag from bursting due to an increase in internal pressure.

That is, since the packaging bag of the present invention can be used consistently throughout distribution, storage, and cooking, it is very convenient to handle and saves labor, and at the same time, has an effect of saving resources.

[Brief description of drawings]

1 and 2 are sectional views of a side sheet of a packaging bag, FIG.
FIG. 4 is a plan view showing the pattern of the intermittent resin layer of the same as above.
The figure is a cross-sectional view of the inner bottom sheet, FIG. 5 is the cross-sectional view of the outer bottom sheet, FIG. 6 is an exploded perspective view of the packaging bag, FIG. 7 is a completed plan view of the same as above, and FIG. 8 is a complete seal of the same. FIG. 9 is a plan view showing a state in which the metal thin film layer has been peeled off, and FIG. 1 ... Side sheet, 2 ... Synthetic resin base material, 3 ... Heat fusion layer, 4 ... Resin layer, 5 ... Adhesive layer, 6 ... Metal thin film layer, 6 '... Reinforcing layer, 7 ...... Surface protection layer, 8, 9 ...... Heat seal part, 10 ...... Inner bottom sheet, 11 …… Synthetic resin base material,
12 …… Heat fusion layer, 13 …… Notch, 20 …… Outside bottom sheet,
21 …… Metal thin film layer, 22 …… Heat fusion layer, 24 …… Notch.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-62-122952 (JP, A) JP-A-62-146155 (JP, A) Actual development: JP-A-60-90143 (JP, U)

Claims (1)

[Claims] 1. A gas barrier layer including a metal thin film layer on an outer surface of a synthetic resin substrate whose inner surface is heat-sealable, with an adhesive layer and an easily peelable joining layer made of a resin layer having a weaker adhesive strength than the adhesive layer. Laminated side sheet, two-fold synthetic resin inner bottom sheet with outer surface heat-sealable and notched at both ends, and outer surface heat-sealable with a metal thin film layer provided with notches at both ends The outer bottom sheet is folded in two, and the inner bottom sheet is folded in two so that the outer bottom sheets are overlapped with each other so that the cutouts of the outer bottom sheet and the inner bottom surface sheet face each other. It is inserted in the lower part of the side sheet, the lower edge of the inner bottom sheet is positioned above the lower edge of the side sheet, and the lower edge of the outer bottom sheet is substantially aligned with the lower edge of the side sheet. The edges are heat-sealed and the inner bottom surface is Side edges and lower edges of the outer side sheet and the inner surface of the side sheet are heat-sealed, and the lower edge portion of the outer bottom sheet and the inner surface of the side sheet are heat-sealed, and cut along substantially the lower edge of the inner bottom sheet. A packaging bag that can be made independent by doing.