High capacitance valve metal powder

摘要

A high capacitance, low specific surface and low oxygen content 'acidic earth' metal (Nb, Ta) powder consisting of agglomerates, for mfg. sintered anodes for electrolytic capacitors, is claimed, the novelty being that sintered anodes, made from the powder by pressing to 4.5g/cu.cm. density and sintering 20 mins. at 1400 deg.C, have a specific electric charge of more than 25 m C/g. and pref. a specific charge of more than 60 mC/sq.m. based on the surface area of the unsintered powder.Prodn. of the powder involves subjecting the high capacitance powder, obtained by reductive agglomeration, to treatment with complex-forming reagents