Dendritic silver powder

The present invention relates to and provides a new dendritic silver powder which, when mixed with a synthetic resin, gives electroconductive films having sufficient electroconductivity. Even when the films produced from a mixture of the dendritic silver powder and a synthetic resin vary in thickness, the electroconductivity of the films can be maintained. The dendritic silver powder, in an examination with an electron microscope (3,000-10,000 diameters), comprises silver powder particles which each have a shape composed of a trunk and a plurality of branches that branch off perpendicularly or obliquely from the trunk and have grown two- or three-dimensionally (referred to as "special dendritic silver powder particles"), the special dendtritic silver powder particles accounting for 50% or more by number of all the silver powder particles examined. The dendritic silver powder is characterized in that the volume-cumulative particle diameter D50 (referred to as "D50D") determined by adding the silver powder to water containing a dispersant, applying 300-watt ultrasonic waves to the resultant mixture for 3 minutes, and examining the dispersion with a laser diffraction/scattering type particle size analyzer is 1.0-15.0 µm and that the ratio of the volume-cumulative particle diameter D50 (referred to as "D50N") determined by adding the silver powder to the water containing a dispersant and examining the mixture under the same conditions as for the D50D except that no ultrasonic waves are applied, to the D50D, D50N/D50D, is 1.0-10.0.