VERFAHREN ZUR HERSTELLUNG VON FLACHEN FOLIEN UND PLATTEN AUS POLYMERSTOFFEN UND EINRICHTUNG ZU DESSEN DURCHFUEHRUNG

摘要

Flat foils and sheets are made from polymeric materials by extrusion from a slotted nozzle, electrostatic charging of the foil, stretching between nozzle and an intermediate roll and final cooling on a cooling roll. In the space between the intermediate roll and the cooling surface of the final roll, the polymeric web is subject to an additional longitudinal stretch. Method results in a substantial improvement of the quality of the flat foil produced. The device is simple in design. The manufacturing costs have been reduced by changes in the stretch deformation and the cooling of the polymer foil.