| 摘要 |
The zone of weakening, which is designed as a slot (6a), is bordered by film material (7) on both sides according to length, i.e., across the direction of loading, which is indicated by the arrows F. Tearing (8) which progresses from the edge because of microscopic damage comes to a standstill at the slot (6a) at the latest, because stress peaks are dissipated here and the locally increased stresses are diverted into elements of the film material (7) which are under less stress. Other embodiments include a locally interrupted adhesive layer for separation of an upper film layer from a lower film layer, these two film layers being otherwise glued together. The adhesive-free recesses here constitute zones of weakening in the sense of the present invention. This therefore prevents tears from spreading from one film layer to the next. Furthermore, the propagation of tearing is counteracted due to the dissipation of stresses when a tear that forms in the film layer reaches the zone of weakening.
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