Plastic zipper having preventing function against unfairly unsealing, and the manufacturing method and manufacturing appartus thereof

Abstract

In a plastic zipper 1 having a pair of engaging portions 1A and 1B formed on surfaces of plastic films F, a plastic zipper having preventing function against unfairly unsealing is provided wherein a tear tape 5 is detachably welded to the top surfaces at mouth side of the plastic zipper in a longitudinal direction of the plastic zipper, and thus, it can be ascertained at a glance that it is unsealed unfairly or erroneously.The plastic zipper is guided between two guide rails 3A and 3B, disposed in parallel to each other and forming a space therebetween, and pairs of guide rollers 2A and 2B, and a tear-tape having easily peelable plastic layer formed on one surface thereof is guided to the space between the guide rails 3A and 3B, and then, both of them are welded together by hot stamping by means of a heating member.

Description

TECHNICAL FIELD[0001]The present invention relates to prevention against unfairly unsealing of a plastic zipper, of a plastic zipper with a slider, and of a bag equipped with the plastic zipper, which are easily opened and re-closable while they keep hermetic sealing, and which are used as packaging materials of foods, medicines, electronic products, etc.BACKGROUND ART[0002]Bags equipped with plastic zippers are widely used as packing materials for foods, medicines, electronic products and other goods. Especially, bags equipped with plastic zippers with sliders are widely used as packing materials which are easily opened and re-sealable.[0003]However, with diversification of contents of packages, further more advanced air tightness has been required for a package, and an additional function of a package wherein broken seal can be detected after it has been hermatically sealed is desired because the sealed package which has been opened by wrong purpose or by an inaccurate error may c...

AI Technical Summary

Benefits of technology

[0044]According to the manufacturing apparatus and the manufacturing method of the present invention, the plastic zipper, the top surfaces of which located at the mouth side is detachably welded in a longitudinal direction, or which has a tear tape having easily peelable plastic layer detachably welded at the top surfaces located at the mouth side thereof, can be produced industrially and effectively.

[0045]Since the plastic zipper of the present invention has the tear tape having the easily peelable plastic layer detachably welded at the top surfaces located at the mouth side thereof, the tear tape will be peeled off when the plastic zipper is subjected to unfair or erroneous unsealing. Under such a condition, even if a person who has performed unfair action tries to return it to its former condition, the former condition cannot be returned any more. Further, the fact wherein the unsealing operation has be done can be understood at a glance from its appearance. Especially when the tear tape is used, even if a part of the tear tape has been peeled off, the fact wherein the unsealing operation has been done can be understood at a glance, since the peeled off portion flutters. Further, in the event wherein the tear tape has cuts made from the side edge thereof and a plurality of slits are formed, the tear tape will be cut off, when the tear tape is subjected to a peeling off operation from the side edge, and accordingly, it can be understood that it has been subjected to an unfair unsealing operation. In the case of the plastic zipper with the slider, if such slits are obliquely cut towards the closed end of the zipper, the tear tape will be cut off or peeled off when the slider is moved with the tear tape adhered thereto, and accordingly, it can be understood that it has been subjected to an unfair or erroneous unsealing operation.

[0046]Also in the case of the plastic zipper which has the top surfaces at the mouth side continuously welded to each other in a longitudinal direction, the welded portion of the top surfaces at the mouth side will be cut off or broken when the plastic zipper is unfairly or erroneously unsealed, and accordingly, the fact wherein the unsealing operation has be done can be understood at a glance.

[0047]As described above, because everyone can understand easily that unsealing operation has been done from the appearance, an intention to try to unfairly unseal is ceased. Therefore, it can prevent unfair unsealing.

[0048]Since the plastic zipper of the present invention can be produced industrially by using a manufacturing apparatus, it can be produced effectively.

[0049]Further, when the function of the present invention for preventing unfairly unsealing is added to such a hermetic plastic zipper as disclosed in Patent document 1 or 2 wherein engaging portions comprise a pair of male and the female hooks and which has a continuous tightening wall inside one of the hooks and a continuous pressing rib inside the other hook, a bag with slider can be provided which is used with assumption of long time preservation and hermetical re-seal after unsealing.

Problems solved by technology

However, with diversification of contents of packages, further more advanced air tightness has been required for a package, and an additional function of a package wherein broken seal can be detected after it has been hermatically sealed is desired because the sealed package which has been opened by wrong purpose or by an inaccurate error may cause various troubles such as mixing of foreign substances or spoiling of quality of contents in the package.

However, there is a disadvantage that the bag has bad appearance and inferior industrial productivity.

However, when contents of the bag are fine particles such as powder, there causes a problem that the fine particles are clogged on a portion of the partitioning film and cannot be discharged smoothly.

However, in this example, since the films at the upper portion of the zipper are closely in contact with each other, it is hard to judge from appearance whether or not the spot welded portion is cut off when the zipper is in a closed state.

This example applies a system wherein the upper portion of the zipper is cut off from the perforations by means of the slider when it is opened, however, sometimes cutting off may not be done well.

However, the Patent document 3 discloses in concrete neither an apparatus nor a method for industrially carrying out such welding.

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