Cure-adhesion of rubber to electroless Pd-P alloy deposit: effect of P content in alloy

The cure-adhesion of rubber to electroless plating film of Pd-P alloy and the adhesion mechanism has been investigated. In that cure-adhesion, the adherents had high adhesion force, and adhesion failure was the cohesive failure of rubber. The peel strength decreased with an increasing P content in plating film of Pd-P alloy. When P content increased in alloy, the reaction between Pd and sulfur in rubber was depressed because the oxide film was formed readily. In the evaluation of adherence of rubber and metal, the solderability was superior to the analysis of X-ray photoelectron spectroscopy (ESCA). ESCA and Rutherford backscattering spectroscopy analyses on the adhesion interface suggested that high bond-durability was achieved when ca.30 nm thickness of sulfide layer was formed in the interface. Reflection electron diffraction analysis of the sulfide layer proved formation of PdS2.