Improvements relating to the formation of metallic coatings

摘要: A process for the production of a metallic coating on basis metal, e.g. copper, brass, nickel-silver, beryllium-copper or iron nickel cobalt alloys, comprises treating said metal with an acid solution, 250 ml./litre conc. HCl, salt platinum 1-10 g./p./l., so as to dissolve more than is chemically replaced, give thick, 0.4-1.3m , porous pores which are subsequently sealed by chemical reaction. Pt, Pd and Rh may be used their chlorides (simple complexed) but Ru ammonium ruthenium nitrosochloride sulphamate at 95 DEG C. solutions 25 Pt 65 The in this first then preferably deposition such gold sealing hydroxide without hydrazine, potassium iodide sodium solution silver nitrate also disclosed. treatment printed circuits, electrical contact members transistor bases iron-cobalt alloy U.S.A. Specification 2,532,283 referred to.