JPS6013660A - Vessel for packing stretched film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a stretch film packaging container that is wrapped with a stretch film while containing articles therein.

[Technical background of the invention]

This type of packaging container is generally made of plastic and is shaped like a plate, and for example, fish, meat, vegetables, etc. are stored therein and wrapped in a stretch film. The edge portion of the film that wrapped this packaging container was
The packaging container is pressed against an electric heating plate and thermally welded.

[Problems with background technology]

However, this stretch film packaging relies so much on the self-adhesive properties of the film that the sealing technology between the film and the packaging container is lagging behind, and the following unique problems have arisen and remain unsolved.

First of all, the conventional method for welding the edges of stretch film is an external heating method in which the packaging container is pressed against an electric heating plate and heat welded, and the folded edges are welded together and sealed. However, the edge portion of the film was not welded to the tray itself. The reason for this is that the packaging container for this scale is made of foamed resin such as Styrofoam containing many air bubbles, and even if you try to weld the film directly to it, most of the volume of the foamed resin will be lost. The film is well welded even though it is occupied by air bubbles! That's because you don't get it. Therefore, in the conventional method, a complete seal cannot be obtained unless the edge portions of the film are completely welded to each other. However, in reality, even if the welding of the edge portions to each other is incomplete, a certain degree of welding can be simulated due to self-adhesion, so even incomplete welding is considered to be a complete package.

Second, in manual stretch film packaging, the edges of the film are pulled by hand, so the shape of the edges is not like that of multiple layers of film neatly stacked on top of each other, but rather, the shape of the edges is not like that of multiple layers of film stacked neatly on top of each other. Jζ was tied up and pulled together
The reality is that the material is extremely rough and thick, almost like a piece of paper being rolled or folded, and as a result, incomplete welding is likely to occur, especially at the edges. Moreover, the film is always in a state of tension, and the contraction force acts as a separation force, and the moisture in the air trapped in the ears liquefies and turns into snow due to cold air. It loses its self-adhesiveness and partially peels off at the edges during production, storage in the freezer in the wholesale sector, storage in frozen showcases in the retail sector, and storage in the refrigerator at home, resulting in spillage and odor. There were problems such as metastasis. In order to completely weld the edges, it is necessary to raise the temperature of the electric heating plate considerably, but this will cause the film to become thinner due to stretching.
There is a problem in that a hole formation phenomenon occurs in the curved portion or the portion where a small number of sheets overlap.

(Object of the Invention) An object of the present invention is to provide a stretch film packaging container in which the edge portions of the stretch film can be reliably welded to obtain a reliable sealing state by the stretch film.

[Summary of the invention]

The present invention is characterized in that a heat-transmitting material that generates heat when irradiated with external energy is attached to at least a part of the outer bottom of the container body,
The edge part of the stretch film is welded to the outer bottom of the container body through a welding auxiliary layer of 181 layers by the light and heat of the heat-transmitting moon, and then The main feature of this product is that it prevents gaps from forming between the container body and the stretch film.

(Embodiment of the Invention) An embodiment of the present invention will be described below with reference to FIG. 1 to FIG. 8. Reference numeral 1 denotes a 1-lay which is a container for stretch film packaging according to the present invention, and the container main body 1 and main body 2 are made of a foamable resin such as foamed cotton wool. At least a portion of the outer bottom surface of the tray main body 2, for example, the lower surface of the bottom portion 2a, is covered with, for example, aluminum foil 3 by welding or the like as a heat transmitting member. Further, on this aluminum foil 3 is laminated a PLUSDEC film 3a which is a heat-meltable auxiliary layer.

Next, FIGS. 2 and 3 show that a long film is cut to a predetermined length, the cut film is used to wrap the tray main body 2, and the film that wraps the tray main body 2 is shown in FIG. This shows a manual stretch film wrapping machine for welding the edge portion of the tray to the main body 2 of the tray, and its configuration will be explained next. Reference numeral 4 denotes a film storage section installed at the rear of the base 5, and a guide roller 6 and a pair of brake cylinders 7 are installed inside the film storage section.
is installed. 8 is a film cylinder placed across a pair of brakes ffW 7, which is made into a cylinder by winding a long film 9 made of a stretch film having extensibility and self-adhesiveness. It is. Such a film cylinder 8 is in close contact with the brake cylinder 7, and when the film 9 is pulled out, it rotates on its own axis and rotates the brake cylinder 7. However, even if the film 9 is pulled out forcefully, the film cylinder 8 does not touch the brake cylinder 7.
It is possible to prevent the film 9 from idling without being pulled out. 1o is a heating wire stretched in front of the film storage section 4, 11 is a rotatable cable installed between the film storage section 4 and the heating wire 1o, and this movable +111 is a tension wire. It is always urged to rotate in the direction of the arrow by a spring 12. 13 is a switch mounted in the base 5 ("J"), which responds to the rotation of the movable rod 11 in the direction opposite to the arrow. 1/'I is a film welding table with the mounting surface 15 to the right, and since the mounting surface 15 is made of a non-magnetic material, the back side thereof is A guidance: 1 ile 16 is provided.

Next, let's talk about the effect of the above configuration.

Turn on the main power switch (not shown), and then
It is inserted between the blade ml-ra 6 and the movable + 411 and pulled out for a predetermined length from the outlet 4a of the storage part 4. Then, by using the braking force of the braking tube 7 and keeping the pulled out film 9 in a stretched state, the film 9 is wound around the main body 2 containing foods, etc., and the film 9 is pulled downward. Film 9 is movable rod 1
1 is rotated in the opposite direction of the arrow against the spring force of the tension spring 12. Then, the switch 13 responds to the rotation of the movable +111 in the direction opposite to the arrow, and the heating wire 10 is energized.
The film 9 in contact with the heating wire 10 is melted 1i. After this, both J of the film 9a around which the main body 2 is wound:
f 61i 9 b by hand and pull it left and right to extend the assembly part 91) of the tray main body 2 as shown by arrow B.
Fold it towards the bottom and wrap it up as shown in Figure 5.
The self-adhesion of the film 9a temporarily holds it in that state. Therefore, on the bottom surface of the tray main body 2, the film 9
As the edge portion of b, there is a non-small portion 17 of only one sheet, and a small number of folded overlapping portions 18 of two sheets jI7 overlapping,
It can be seen that a multi-fold overlapped portion 19 in which E or more sheets overlap occurs.

After this, the bottom surface of the main body 2 wrapped in the film 9a as described above is placed on the mounting surface 15 of the film welding table 14, and the induction coil and coil 16 are connected to each other.
Pass current. Then, an alternating magnetic field is formed by the induction coil 16;

An eddy current is generated in the aluminum foil 3 of the tray main body 2 that exists inside, and the aluminum foil 3 generates heat due to Joule heat caused by the eddy current, melting the plastic film 3a and attaching the edge portion of the film 9a to the tray main body 2. It is welded to the bottom surface of the.

In this way, unlike the conventional external heating method using an electric heating plate, this embodiment uses an internal heating method in which the J~Sire itself becomes a heating element and heats from the inside.
~The plastic film 3a on the lower surface of the lower surface of the plastic film 3a is melted, and the edge portion of the film 9a in contact with it is welded to the 1-layer body 2 itself, and then folded to the outside to form the lζ edge portion. are sequentially welded.

Therefore, not only the film 9a that is directly behind the aluminum foil 3 is welded to the tray main body 2, but also the films 9a that are sequentially stacked on the aluminum foil 3 are welded to each other. Since it can be welded to the main body 2, the film 9 on which the juice in the tray and main body 2 is sequentially layered.
It is possible to reliably prevent seepage from between the phases U of a, and to achieve a complete seal. However, as shown above, the aluminum foil 3 is J3 on the bottom 1r11 of the main body 2 of 1 to 1.
Even though it is hot, the tray body 2 is made of foamed resin, so it is insulated.
- No problem occurs when storing frozen foods, for example, in the main body 2. In addition, this embodiment is an internal heating type, and the edge portion of the film can be directly welded to the tray main body 2, so a complete 4J seal can be obtained and, for example, as shown in FIG. In particular, since there is no need to fold the film over, it is easier to weld the edges of the film together than in the past.
The use m of a decreases. Moreover, even if the entire particularly thick ear portion 9b is not completely welded, especially in the folded portion 19 of a large number of sheets, as shown in FIGS. 7 and 8, the periphery of the thick portion is welded to the tray main body 2. Because there is (
(For convenience, the welded portion is indicated by an X mark), so there is no risk that the sealing performance will be impaired. Therefore, a reliable seal can be obtained without increasing the heat generation temperature of the aluminum foil 3 so much, and it is possible to prevent the phenomenon of holes forming in the non-small portion 17 and the small fold portion 18. Furthermore, the packaged items such as food stored in the tray 1 come into contact with the inner bottom surface of the tray main body 2, and heat-generating aluminum foil 3 is attached to the outer bottom surface of the tray main body 2. Even under these circumstances, the tray main body 2 is made of foamed plastic that contains many air bubbles and has high insulation properties, so the heat generated in the aluminum foil 3 will not be transferred to the food, etc. .

It should be noted that the present invention is not limited to the embodiments described above and shown in the drawings; for example, as shown in FIG. A heat-transmitting material is formed on the lower surface of the other portions except for the protruding stripes 21, and an aluminum layer 22 is diluted by steaming. The plastic film 25a may also be provided separately. Furthermore, although not shown, an elastic protrusion is provided on the mounting surface 15 of the film welding table 14 so that when the film welding table 14 is pressed against the mounting surface 15, the parts of the film 9a where the number of overlapping sheets is large ( The structure may be such that a larger pressing force is applied.1..1./The structure may be such that a single sheet of aluminum foil is used, or small pieces may be scattered.

Furthermore, although aluminum was used as the -b dielectric material in each of the ten td embodiments, other metals may be used, and instead of the induction coil 16, a microwave oscillator, an ultrasonic oscillator, etc. may be provided. , non-metallic materials can be used as heat-transmitting materials.

(Effects of the Invention) As described above, the present invention is characterized in that at least a portion of the outer bottom surface of a container body made of foamed resin is coated with a heat-transmitting material that generates heat when irradiated with external energy. The feature is that the edges of the wrapping stretch film are welded to the outer bottom surface of the container body by the heat generated by the heat-transmitting material through a heat-melting welding auxiliary layer provided on the heat-transmitting material. As a result, the heat-transmitting material generates heat due to external energy irradiation, and the stretch film that is in contact with the welding auxiliary layer can sequentially melt the many sheets of stretch film located outside the welding auxiliary layer. Not only can the film be welded to the container body via the heat-transmitting material, but the stretch films can also be welded to each other, so that the stretch films in the folded portions can be firmly adhered to each other and attached to the bottom of the container body. Can be welded to
As a result, the juice inside the container body can be reliably prevented from seeping out, and a complete seal can be achieved.

[Brief explanation of the drawing]

Figures 1 to 8 show one embodiment of the present invention, with Figure 1 being a cross-sectional view of a tray, and Figures 2 and 3 being a cross-sectional view and partially cutaway view of a manual stretch film packaging machine. 'Perspective view,
Fig. 4 is a perspective view showing the process of packaging the tray with a film, Figs. 9 is a cross-sectional view taken along lines 1 and 2, and FIG. 9 is a view corresponding to FIG. 1 showing another embodiment of the present invention. In the figure, 1 is a tray (stretch film packaging container),
2.20 is the tray body (container body), 3 is aluminum foil (heat-transmitting material), 3a, 25a are plastic films (welding auxiliary layer), 9 is stretch film, 10 is heating wire, 14
1 is a film welding table, 16 is an M conductive coil, and 22 is an aluminum layer (heat-transmitting material). Applicant Shigeru Ikemoto 1 Figure 2 Figure 3 Figure 4b Figure 5 Figure 6

Claims (1)

[Claims] 1. A container body made of foamed resin for storing articles is covered with a stretch film, and the edge portion of the stretch film is welded to the bottom of the container body, in which at least the outer bottom of the container body is covered with a stretch film. A heat transmitting material that generates heat upon irradiation with external energy is attached to a part of the container body, and the edge portion of the stretch film that wraps the container body is attached to the heat generated by the heat transmitting material. A stretch film packaging container which can be welded to the outer bottom surface of the container body via a meltable welding auxiliary layer.