| 摘要 |
In coating metal units or structures with a heat-hardening powder based on a polyester resin and/or an epoxy resin, which is sprayed on by means of an electrostatic spray gun and then polymerised in an oven, the pieces to be coated are pre-treated by: (a) an electrolytic zinc plating; and (b) application of a coat of varnish, followed by drying, baking or polymerisation of the varnish. This coating acts as a bonding underlayer between the metal and the polyester and/or epoxy resin outer coating. Pref. the varnish is acrylic and is polymerised in an oven. The thickness of the varnish layer is 2-30 (5-15) microns. The varnish is applied by dipping or spraying. |
