NICKEL POWDER AND PROCESS FOR PRODUCING THE SAME

摘要

Inexpensive nickel powder exhibiting excellent weatherability and a low electric resistance under a state of being kneaded with resin, capable of long-term stabilized use, and suitable as conductive particles for conductive paste and conductive resin, and its producing process. The nickel powder, being produced from an aqueous solution containing a bivalent nickel salt by reductive deposition process in two stages, has an average primary particle diameter of 0.2-2.0 mum determined by observation under a scanning electron microscope (SEM), an average secondary particle diameter of 8-50 mum determined by measuring laser grain size distribution, a tap density of 0.5-2.0 g/ml and contains 1-20 wt% of cobalt. Cobalt may be contained by 1-40 wt% only in the surface layer of nickel powder.