Environmentally Friendly Copper Metallization of ABS by Cu-Catalysed Electroless Process

An environment-friendly surface etching and activation technique for ABS surface metallization were investigated as a replacement for conventional chromic acid etching bath and palladium catalyst. After etching by H2SO4-MnO2 colloid, the ABS surfaces became rough; meanwhile the carboxyl and hydroxyl groups were formed on the surface. With absorption and reduction by a sodium borohydride solution, copper particles were deposited on the ABS surface, which serve as a catalyst replacement for SnCl2/PdCl2 colloid. The effects of CuSO4 concentration, NaBH4 concentration, reduction temperature and reduction time on the adhesion strength between the ABS surface and the electroless copper film were investigated. The average adhesion strengths reaches 0.87 kN·m−1.