TUNGSTEN POWDER, POSITIVE ELECTRODE BODY FOR CAPACITORS, AND ELECTROLYTIC CAPACITOR

摘要

The present invention provides a tungsten powder for electrolytic capacitors, which has elemental germanium only in a particle surface region such that the content of the elemental germanium is 0.05-7% by mass, and which has good leakage current (LC) performance. It is preferable that: the tungsten powder has a volume average primary particle diameter of 0.1-1 μm; the elemental germanium is localized in a region from the particle surface to the position 50 nm deep toward the inside of the particle in each particle; at least one selected from among tungsten silicide, tungsten carbide, tungsten boride and tungsten in which nitrogen is solid-solved is present only in a particle surface region; the content of elemental phosphorus is 1-500 ppm by mass; and the oxygen content is 0.05-8% by mass.