Pretreating e.g. plastic film before vacuum depositing seal on it - by passing film round roller where it is exposed to plasmas produced by two successive ribbed high frequency hollow anodes

摘要

The surface of a substrate is pretreated before an inorganic seal is applied to it, where that seal is evaporated under vacuum from a pot and then deposited on the surface concerned. In the process the substrate is passed at high speed through the vacuum chamber and exposed to the action of a plasma. The process pref. utilises a film of polyethylene-terephthalate, polyethylene, polypropylene or polyamide. ADVANTAGE - The procedure bonds the seal layer to the substrate and produces a durable coating. It is useful in making packaging material which keeps its contents in good condition for long time.