Corona discharge foil surface treatment - has foil drawn between pair of charged electrodes of which one has quartz coating

摘要

To improve the bonding qualities of foils, sheets or plastic shaped parts, their surface is pre-treated by corona discharge. Instead of a set of stationary and rotating electrodes only a set of stationary electrodes are used with a permanent coating of quartz. The electrode itself is a metal body with the quartz coating fused-on. The electrode can be shaped to handle workpieces with poorly accessible corners. During the operation the temp. of the quartz coating may increase to a critical point, where the quartz loses its insulating capability and cooling by air stream has to be applied.