JPS5929851Y2 - packaging containers - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a packaging container made of synthetic resin, and more particularly to a container structure that prevents deterioration in the appearance of the container caused by deformation due to depressurization of the container enclosing an oxygen absorber or the like.

Conventionally, degassing or vacuum packaging has been adopted for soft packaging or pouch packaging for pickles, snacks, etc., in order to suppress chemical changes in foods such as changes in oil and fat components and discoloration due to oxygen. Gas replacement is used for cans, etc., but with the recent development of oxygen absorbers, packaging formats that absorb the oxygen inside the container and suppress the oxidation of the food contents are now being adopted. Ta.

By the way, when using this oxygen absorber, it is extremely simple as it does not require any special equipment or equipment for vacuum suction or gas replacement, but of course it absorbs oxygen from the air inside the container. Because of this, the volume inside the container decreases, resulting in a reduced pressure state.

In normal cases, the top film coated on the top surface of the container or the bottom surface of the container is recessed inward, impairing the appearance and significantly reducing the commercial value.

This idea was proposed in order to prevent such deformation of the container from reducing its commercial value.By forming a bellows part in advance on the upper side wall of the container body, it is possible to reduce the pressure caused by oxygen absorption. It is characterized in that the deformation of the container body is absorbed by the bellows portion, so that no deformation is caused to the top film portion, which is the top surface of the product, or to the bottom portion of the container.

The details of this invention will be explained below with reference to the attached drawings.

FIG. 1 is a plan view of a container body 10 showing an embodiment of this invention, FIG. 2 is an end view of the container covered with a top film 19, and FIG. 3 is an enlarged end view of a portion thereof.

As shown in FIGS. 1 to 3, in the packaging container according to the present invention, the upper side wall 11 of the tray-shaped container body 10 is formed into a bellows shape 12, and the flange portion on the upper surface of the container body 10 At 13, a top film 19 is welded.

In the embodiment shown in FIG. 3, the container body 10 has an outer layer 10a made of polyolefin, styrene or nylon, an intermediate layer 10b made of vinylidene chloride with high oxygen barrier properties, or an ethylene-vinyl acetate copolymer, etc., and an inner layer 10C made of polyolefin, styrene or nylon. It is molded from a laminate of synthetic resin sheets or films such as polyolefin.

In addition, a two-layer structure may be used in which the outer layer is made of nylon and the inner layer is made of polyolefin or the like.

On the other hand, in the embodiment of FIG. 3, the top film 19 also has an outer layer 19a made of polyethylene terephthalate and an intermediate layer 19a made of polyethylene terephthalate.
b is vinylidene chloride or ethylene vinyl acetate copolymer having high barrier properties, and inner layer 19 is a laminated synthetic resin sheet or film such as polyolefin.

It goes without saying that it is desirable to use materials with high oxygen barrier properties for the container body 10 and the top film 19, as described above.

Next, the bellows part 1 is formed on the upper side wall 11 of the container body 10.
2, the diameter of the bend is small as shown in the figure, and the peak portion 12 a
The deeper the depth of the valley portion 12b, the greater the contractility.

Therefore, it is desirable that the surface connecting the peaks 12 a and the valleys 12 b of the bellows portion 12 be substantially parallel to the side wall 11 or at an acute angle.

Moreover, each mountain part 12a, 12a of the bellows part 12...
If the container is constructed such that it gradually descends toward the center of the container, the side wall moves inward during contraction, and the inclined surface of the side wall moves in the vertical direction, which is preferable in terms of appearance.

It is desirable that the configuration of the bellows part 12 in the container body 10 be designed in such a way that the volume (oxygen content) is reduced by about one-fifth of the remaining volume in the container when the contents are sealed. FIG. 4 is an end view showing the function of the container according to this invention.
When oxygen in the container is absorbed by the oxygen scavenger 25, the bellows portion 12 on the upper side wall contracts, and the side wall 11 moves from the position indicated by the chain line to the position indicated by the solid line.

However, the phenomenon of the top film 19 sinking inward does not occur.

FIG. 5 shows a conventional container 30 without bellows. In this case, when the pressure is reduced by the oxygen scavenger 25, the top film 19 on the top of the container or the bottom of the container body collapses inward. Appearance is significantly impaired.

In this way, according to this invention, the volume reduction due to oxygen absorption inside the container is absorbed by the bellows on the side wall. There is no deformation, so the value of the product is not diminished, and there is no discomfort for consumers, which does not discourage purchasers, unlike in the past.

Further, since the bellows portion on the side wall of the container body can be integrally formed during vacuum forming when forming the container body from a synthetic resin sheet or film, manufacturing is easy.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a container body showing an embodiment of this invention;
Figure 2 is an end view of the container covered with the top film;
The figure is an enlarged end view of a part thereof, FIG. 4 is an end view showing the function of the container according to this invention, and FIG. 5 is an end view showing the function of the container according to the conventional structure. 10... Container body, 11... Side wall, 1
2... Bellows part, 13... Flange part,
19...Tsubu film, 25...Oxygen absorber.

Claims (1)

[Claims for Utility Model Registration] 10 Container body made of synthetic acid-resist sheet or film 1
1. A packaging container characterized in that the upper side wall 11 of the container is formed into a bellows shape 12. 2. The packaging container according to claim 1, wherein the surface connecting the peaks 12a and the valleys 12b of the bellows portion 12 is substantially parallel to the side wall 11 or at an acute angle. 3. Each mountain part 12a of the bellows part 12, 12a...
. . . The packaging container according to claim 1 or 2 of the utility model registration claim, wherein the packaging container is configured such that the . . .