Method for joining several layers of plastic films

摘要

Process for connecting a number of layers of plastic comprises joining the plastic film along an edge by ultra-sound welding. At least two welding points are used, and the welding points have a perforated line parallel to the outer edge of the plastic. The perforation line is e.g. semi-circular and runs around the weld point. The ultrasound welding is carried out using a pin shaped sonotrode.