| 摘要 |
Vacuum tube-type bags, e.g. for foodstuffs in powder form, are generally packed in aluminum foil and repacking is then absolutely essential because of the creased appearence of such a packing. A new composite foil is characterized by the fact that two mutually adjacent layers are bound adhesively to one another, but this bond can be immediately separated. This condition can be affected as soon as the tube-type bag is evacuated in the usual manner, the inner bag shrinks around the article and during this the outer bag is released by removing the adhesion hitherto applied, after which the above mentioned layers become separated. This results in the production of a rather smooth outer bag, although the invisible creased inner bag lays enclosed inside the outer bag. The outer bag can thus be used as the repacking material especially where the composite foil can in no way be distinguished from a usual bag before being used as a packing bag when the vacuum is applied. |
