JPH0227227B2 - HORIFUIRUMUSEIFUKUROTAI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a polyfilm bag whose upper edge can be opened.

(b) Conventional technology Conventionally, polyfilm bags were manufactured using
As described in Publication No. 16182, it is made of a uniform material such as polypropylene or polyethylene,
When used for product packaging, the opening is sealed by heat welding after packaging.

(c) Problems to be solved by the invention However, in such heat welding of the same materials, the entire heat welded part becomes either completely welded or non-welded due to a slight difference in set temperature, so the tack seal is difficult to solve. It is difficult to close the bag in the sealed state (sealed state that can be opened without tearing the film), and with a completely welded closure structure, it is troublesome such as having to tear the bag itself to take out the product inside the bag. It was hot.

An object of the present invention is to provide a polyfilm bag that can solve these problems.

(d) Means for solving the problem The present invention heat-welds the lower edge and left and right edges of two polyfilms to form a U-shaped continuous edge, and It consists of a bag body with an opening at the upper edge having a storage space, and a polyfilm material having a welding temperature lower than the welding temperature of the polyfilm,
It is sandwiched between the inner surfaces of the upper edges of both polyfilms, and is heated from the outer surface of one side of the bag at a temperature that matches the welding temperature of the polyfilm material, to completely weld and incompletely weld the both sides, respectively. The present invention relates to a polyfilm bag comprising a film tape adhered to the inner surface of the polyfilm through a film tape and a film tape adhered to the inner surface of the polyfilm.

(e) Examples The present invention will be specifically described below based on examples shown in the attached drawings.

Note that FIGS. 1 to 3 show a first embodiment of the present invention, and FIGS. 4 to 6 show second to fourth embodiments of the present invention, respectively.

First, the first embodiment will be explained as follows.

In FIGS. 1 to 3, A indicates a bag body, and this bag body A is mainly formed of two polyfilms 1 and 1' made of polypropylene.
Continuous edges 2, 3, which are formed by thermally welding the left and right and lower edges of one polyfilm 1 and the left and right and lower edges of the other polyfilm 1' facing each part, respectively. 4, it retains its bag-like shape.

Further, an opening 6 is formed between the upper inner surfaces 5 and 5' of each of the polyfilms 1 and 1', and the opening 6 has CMPSV which has a lower welding temperature than the polyfilm 1 and 1'. Closing 8 is performed by sandwiching film tape 7 manufactured by Mitsui Polychemical Co., Ltd. (registered trademark).

The structure for closing the opening 6 will be explained as follows.

That is, when the film tape 7 is sandwiched between the openings 6, both sides 9 of the film tape 7,
9' and the upper inner surfaces 5, 5' of the polyfilms 1, 1'
are in contact with each other, and in this state, the film tape 7 is heated from the outside at a temperature (120 to 150°C) that matches the welding temperature of the film tape 7. Both side surfaces 9, 9' are welded to the upper inner surfaces 5, 5' of the polyfilms 1, 1', respectively.

In this case, one side surface 9 of the film tape 7 and the upper inner surface 9 of the polyfilm 1 receive the heating H as they are, so a complete welding part 10 is formed, but the other side surface 9' of the film tape 7 and the upper inner surface 9 of the polyfilm 1 are completely welded. On the inner surface 5', the heating H is applied using a film tape 7.
, the temperature is slightly lowered, forming an incompletely welded part 11, and the incompletely welded part 11
The peel resistance strength is lower than that of the completely welded part 10, and the welding is performed in a moderately tight seal state.

In other words, in thermal welding of different materials, the difference in set temperature for achieving a completely welded state and a non-welded state can be relatively wide compared to the case of thermal welding of the same materials, and within that difference. This structure takes advantage of the fact that incomplete welding, which has weaker peel resistance than a completely welded state, can be achieved.

In addition, 12 and 12' in the figure are polyfilms 1,
1' A gripping part whose center protrudes from the upper part, 1
3 is a packaged product.

Next, the second to fourth embodiments will be explained as follows. In the second embodiment (see FIG. 4), the only difference from the first embodiment is the shape of the gripping portions 12, 12', and the film tape 7 is sandwiched slightly below the upper edge of the rectangular bag A. By wearing the bag A, the rectangular part at the upper edge of the bag body A becomes a gripping part.

The third embodiment (see FIG. 5) differs from the second embodiment only in the sandwiched portion of the film tape 7. In the second embodiment, the film tape 7 is sandwiched over the entire width of the bag body A. However, in the third embodiment, the film tape 7 is sandwiched only in the center of the width, and the polyfilms 1 and 1' are completely welded together on both sides.

In the fourth embodiment (see FIG. 6), the part where the film tape 7 is sandwiched is different from the second embodiment, and the film tape 7 is sandwiched over almost the entire upper edge of the bag body A. Notch 14 in the center of the upper edge of the tape 7
The parts corresponding to the notches 14 are not welded and are used as gripping parts 12, 12'.

The embodiment of the present invention is constructed as described above, and when opening the bag A, the gripping parts 12, 1
2' and pull them in opposite directions, the completely welded part 10 will be formed at the 8 unsealed parts.
A load is applied to the incompletely welded portion 11 and the incompletely welded portion 11 in the respective peeling directions, but since the peeling strength of the incompletely welded portion 11 is weaker than that of the fully welded portion 10, the sealing 8 is such that the incompletely welded portion 11 is peeled off. It is opened by opening the package.

Further, at this time, the incompletely welded part 11 has a weaker peel strength than the conventional completely welded part of the same materials, and there is no possibility that the parts of the bag A other than the closure 8 will be torn when the bag is opened.

(f) Effects With the configuration described above, the present invention has the following effects.

A film tape made of a polyfilm material whose welding temperature is lower than that of the polyfilm is welded between the inner surfaces of both polyfilms without directly heat welding the pair of polyfilms constituting the polyfilm bag, and Since a completely welded part and an incompletely welded part are formed on both sides of the film tape, the bag made of polyfilm is always
The bag can be opened from the incomplete part, and the bag can be opened neatly and reliably without damaging the bag.

[Brief explanation of drawings]

Fig. 1 is a front view of the first embodiment of the present invention, Fig. 2 is a side view of the same embodiment, Fig. 3 is a sectional view taken along the line - Fig. 1, and Fig. 4 is a front view of the second embodiment. , FIG. 5 is a front view of the third embodiment, and FIG. 6 is a front view of the fourth embodiment. A: Bag, 1, 1': Polyfilm, 5, 5':
Inner surface, 6: opening, 7: film tape, 8:
Closed, 9, 9': both sides, H: heating, 10: completely welded part, 11: incompletely welded part, 12, 12': gripping part.

Claims (1)

[Scope of Claims] 1 (a) U-shaped continuous edges 2, 3, 4 are formed by thermally welding the lower edges and left and right edges of two polyfilms 1, 1', respectively. , and a bag body A having an opening at the upper edge and having a storage space therein; (b) made of a polyfilm material having a welding temperature lower than the welding temperature of the polyfilms 1 and 1', and having both side surfaces 9 and 9'; , both polyfilms 1,
The film tape 7 sandwiched between the inner surfaces 5, 5' of the upper edge of the film 1'; A fully welded part 10 and an incompletely welded part 11 are formed between both sides 9 and 5 and between 9' and 5', respectively, by heating H from one outer surface of the bag body A. body.