“Plating on plastics” is a term used to describe the decorative or functional application of metal onto plastic substrates using the process of electroplating. Before plastics can be electroplated they first need to be metalized. This is achieved by etching the surface (to provide a tough bond) and coating the roughened surface with traces of a precious metal. This precious metal provides the 'seeds' for deposited of a thin layer of nickel or copper by electroless deposition.
Etching is achieved in a strongly acidic solution to which special wetter's to reduce surface tension are added. The acid is neutralized, before the precious metal is laid onto the surface. Typically nickel is used at the electroless stage. However when large components are plated, copper is recommended due to its higher conductivity.