Process for making fine perforations in plastic sheeting and/or plastic or rubber coated sheet materials

摘要

A process for making fine perforations in plastic sheeting and/or plastic or rubber coated sheet materials in which the sheeting or the coating is too thick and/or the dielectric constants are too high for electrically making the fine perforations, including the steps of coarsely perforating the material by non-electrical methods, coating the perforated material with a layer of a coating material which is capable of being electrically perforated, and making fine perforations in the layer of the coating material by the use of high-voltage pulses.