JPH0811590B2 - Packaging containers - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a packaging container that accommodates foods and the like and can be cooked in a microwave oven.

[Conventional technology and its problems]

BACKGROUND ART Conventionally, there is an instant food product in which curry, stew, or the like is filled in a plastic container body and a lid material is adhered to the container body by heat sealing to hermetically package.

The lid material used for this type of packaging is often formed of a laminated material including a metal thin film layer such as an aluminum foil in order to improve the barrier property.

However, when the contents such as curry and stew are heated by a microwave oven, the electromagnetic wave is blocked when the metal thin film layer is present in one layer of the laminated material forming the lid material, so the lid material is completely removed from the container body. After that, it was necessary to cover the opening of the container body with a wrap film or the like.

Therefore, an object of the present invention is to eliminate the above-mentioned trouble, so that it is possible to remove only the portion of the metal thin film layer of the lid material, and to prevent the container from bursting due to an increase in internal pressure of the container due to overheating during cooking. The object is to provide a packaging container that can be prevented and is easy to open after cooking.

[Means for achieving the purpose]

In order to achieve the above-mentioned object, in the present invention, at least the inner surface includes a metal thin film layer via an adhesive layer and a resin having weaker adhesive strength on the outer surface of a base material including a base film, which is heat sealable. Stacking gas barrier layers,
A lid material capable of peeling the gas barrier layer portion from the base material by hand is heat-sealed to the opening flange of the container body, and at least the lid material is attached so as not to reach the container opening beyond the heat-sealing portion. The container for packaging was constructed by providing a tab-shaped cut through it.

[Action]

The packaging container has a tab-shaped cut that penetrates at least the lid member so as not to reach the container opening beyond the heat-sealing part. A narrow fan-shaped opening is formed.

Next, since the barrier layer including the metal thin film layer is laminated on the base material via the resin layer having low adhesive strength, it can be easily removed, and when this is removed, the lid material and the main body made of synthetic resin are removed. Remainingly, these do not reflect microwaves and can be cooked in the microwave as they are.

When cooking in a microwave oven, if heated more than necessary, there is a risk of container rupture due to internal pressure rise due to evaporation of moisture in the contents, but since this container has an almost fan-shaped opening, evaporation Moisture that has been released is released from the opening to the outside of the container, and it does not burst and is safe.

〔Example〕

 First, the structure of the lid member will be described.

As shown in FIG. 1, the lid member 1 is made of a metal such as a metal foil or a metal vapor deposition film on the outer surface of the synthetic resin substrate 2 with a resin layer 3 and an adhesive layer 4 having relatively weak adhesive strength interposed therebetween. The thin film layer 5 is laminated. It is preferable to provide the surface protection layer 6 on the outer surface of the metal thin film layer 5. The layer 6 is formed by coating a synthetic resin or laminating a synthetic resin film. In addition, a printing layer can be provided on the outer surface of the layer 5.

As shown in FIG. 2, the base material 2 is a base film.
Although the heat sealing layer 22 is provided on one surface of the layer 21, the layer 22 can be omitted if the base film 21 has the heat sealing property. As the base film 21, polyester,
Nylon (trade name), polypropylene, polyolefin film, and the like are suitable, and either a simple substance or a composite thereof may be used.

Further, as the heat-sealing layer 22, polyolefin, ethylene-vinyl acetate copolymer, ionomer, vinyl chloride-
Vinyl acetate copolymer, acrylic resin, methacrylic resin,
A simple substance or a complex of polyester resin is used. It is preferable to select a resin that can be easily opened according to the material of the container body.

The resin layer 3 is made of a resin having a relatively low adhesive strength, for example, an acrylic resin, a polyamide resin, a silicone resin, a vinyl resin, or a mixture thereof. By partially coating these resins (part coat), It is good to form. An example of the coating pattern is shown in FIG.
Shown in (b) and (c). As shown in the figure, the portion not coated with resin forms a pattern such as a linear shape, a dot shape, or a grid shape. In some cases, the entire surface of the resin is coated,
The layer 3 may be formed. The layer 3 may be provided on the surface of the base material 2 as shown in FIG. 1, but may be provided on the metal thin film layer 5. The point is that the resin layer 3 should be present at the interface of the adhesive layer 4.

As shown in FIG. 4, a reinforcing layer 5 ′ can be provided on the inner surface of the layer 5. This layer 5'is made of polyester, polypropylene, nylon, epoxy resin, etc.
At the same time as preventing the metal thin film layer 5 from being corroded during the retort treatment, it also serves to increase the thickness of the gas barrier layer and facilitate peeling.

FIG. 5 shows a state in which the container body is sealed by the lid member 1 as described above.

As illustrated, the container body 10 has a bottom wall 11 and a peripheral wall 12 continuous with the bottom wall 11, and a flange 13 is provided on the peripheral edge of the opening 15. The container body 10 may be made of a material that does not easily absorb microwaves, and may be a single material such as glass, ceramics, synthetic resin or paper, or a composite material as long as the upper surface of the flange 13 can be heat-sealed. Also, the shape may be any of a round shape and a square shape.

The lid 1 is placed on the flange 13 of the container body 10 and heat-sealed to complete the container. Of course, the contents are enclosed inside the main body 10.

As shown in FIGS. 5 and 6, the lid member 1 is provided with tab-shaped cuts 8. This tab-shaped cut 8
Is penetrating at least the lid member 1, and may be formed in the state of the lid member, or may be formed after heat sealing to the container body 10.
Further, even if it reaches the flange 13 of the container, there is no problem.

In FIG. 6, the cut line 8 has a semicircular shape, but the cut line 8 is not limited to this.
The shape shown in (c) may be used, and it does not matter if the heat sealing part 14 reaches the heat sealing part 14 as shown in FIG.
Do not reach beyond the opening 15 of the container body. This is because not only the barrier property of the container is impaired, but also risks such as dust and sterilization intrusion and leakage of contents occur. There is no problem even if there are a plurality of cuts 8.

Next, regarding the size of the cut line 8, the cut line 8 shown in FIG.
It is determined by the relationship between the distance A between the two ends and the distance B from the end of the cut 8 to the inner edge of the heat sealing portion 14. Now, if the width C of the opening 9 formed by the cuts 8 is constant, it is necessary to increase A as B increases, and conversely, if B is decreased, A also needs to be decreased.

In order to use the container of FIG. 5 for cooking, first, the tab-shaped cut 8 of the lid member 1 is pinched and peeled off in the opening direction to form a substantially fan-shaped opening 9 (see FIG. 8). Next, in the adhesive lacking portion 7 of the lid member 1 (see FIGS. 5 and 6),
Since the gas barrier layer including the metal thin film layer 5 and the base material 2 are separated, when the barrier layer at that portion is pinched and peeled in the opening direction, the gas barrier layer is peeled off on the entire surface, and the base material 2 is It remains in the container body 10. So you can put this container in the microwave and cook. Since the substantially fan-shaped opening 9 is formed in the base material 2, it is possible to prevent the base material 2 from rupturing due to an increase in internal pressure when heated and cooked in a microwave oven. If you peel it off,
It can be opened easily and the contents can be easily taken out. It is also possible to first remove the metal thin film layer 5 and then form the substantially fan-shaped opening 9 in the base material 2.

〔effect〕

According to the present invention, as described above, the lid member composed of the laminated body of the synthetic resin base material and the metal thin film layer is heat-sealed in the container body, and the container opening is prevented from reaching the container opening beyond the heat-sealing part. Since at least a tab-shaped cut that penetrates through the lid member is provided, there is no fear that the barrier will be impeded by this cut, and it is possible to effectively prevent alteration of the contents,
Further, it is suitable for heating in a microwave oven because it does not break from the cuts due to impact during handling, and in addition, only the metal thin film layer can be peeled off by an easy operation. Furthermore, the substantially fan-shaped opening allows for prevention of rupture due to an increase in internal pressure during heating and cooking in a microwave oven, and the base material can be easily opened and removed from the container after cooking, so that the contents can be easily taken out. Further, since the size of the substantially fan-shaped opening can be controlled to some extent, for example, a hygroscopic powder such as "soup stock" is filled, water is poured from the opening at the time of use and cooked in a microwave oven. Such usage is also possible.

That is, since the packaging container of the present invention can be used consistently from distribution to storage to 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 is a cross-sectional view of the lid material, FIG. 2 is a cross-sectional view of the same base material,
FIG. 3 is a plan view showing a coating pattern of a resin layer having a weak adhesive force in FIG. 1, FIG. 4 is a cross-sectional view showing another example of the lid member, and FIG.
The figure is a sectional view of the container, FIG. 6 is a plan view of the same as above, FIG. 7 is a plan view showing the shape of the tab-like cut, and FIG. 8 is a plan view showing the relationship between the tab-like cut and the opening. 1 ... Lid material, 2 ... Base material, 3 ... Resin layer with weak adhesive strength, 4 ... Adhesive layer, 5 ... Metal thin film layer, 8 ... Tab-like cut, 9 ... Opening, 10 ... … Container body, 13 …… Flange,
14 …… Heat seal part, 15 …… Opening part.

Claims (1)

[Claims] 1. A gas barrier layer including a metal thin film layer is laminated on an outer surface of a base material including at least an inner surface that can be heat-sealed and a base film via an adhesive layer and a resin layer having a weaker adhesive strength than the adhesive layer. A lid material that allows the gas barrier layer to be peeled off from the base material by hand is heat-sealed to the opening flange of the container body, and at least the lid material is arranged so as not to reach the opening portion of the container body beyond the heat-sealing portion. A packaging container provided with a tab-shaped cut that penetrates through.