Abstract: This invention provides a process of making a palladium replenisher comprising a complex of palladium tetraammine sulfate. The process includes distilling a palladium nitrate solution at a temperature maintained at or below about 115° C. Palladium sulfate and ammonium hydroxide are then added to make the palladium tetraamine sulfate replenisher from solution. The replenisher of the invention is used to replenish depleted palladium during palladium electroplating to maintain the palladium concentration in the bath within from about 5 to about 10 weight percent of recommended plating bath levels.

Abstract: An electrical connector comprises connector contacts having a metal base and a surface finish layer over the base, the surface finish layer being a composite of an electroplated precious metal composition and wear resistant particles dispersed therein. In the preferred embodiment, the precious metal layer is a PdCo alloy and the wear resistant particles are sub-micron sized lubricating particles, e.g. polytetrafluoroethylene particles and a flash coat of gold is provided over the composite layer.

Abstract: The specification describes novel rhodium sulfate complex solutions which have a minimum of metal to metal complexing and are mostly complexed through the sulfate groups. Use of these solutions as electrolytes for plating rhodium results in electroplated layers with improved brightness and reduced stress.