Surface treatment of plastics by corona discharge

摘要

Equipment for the surface treatment of a substrate by corona discharge has a ceramic electrode (3) in a housing (1) which can be supplied with a carrier gas. A cooling medium flows inside passages (2) within the housing wall and the electrode operates at a temperature greater than 150 deg C. The housing is of inverted U shape section and made of e.g. aluminium with cooling channels (2) for e.g. water within the walls. The electrode support (11), which is made of heat resistant material, raises the electrode from its working position near the substrate to a rest position by means of a hinged linkage (13). At the same time the lever system closes split covers (12) round the bottom of the electrode to protect it. Carrier gas, containing e.g. an aerosol or powder, is supplied through jets at the end of one limb of the housing (1) and drawn off by suction at the other to give a flow through the housing. The gas is pref. recirculated.