HIGHLY CRYSTALLINE SILVER POWDER AND METHOD FOR PRODUCTION THEREOF

摘要

An object of the present invention is to provide highly crystalline silver powder which is characterized in fine particles, showing high dispersibility, it's particle size distribution is not excessively sharp but relatively broad and crystallites are large; and a method for producing the same. In order to achieve the object, a method for producing highly crystalline silver powder is characterized in that mixing a first aqueous solution and a second aqueous solution, wherein the first aqueous solution contains silver nitrate, a dispersing agent and nitric acid, and the second solution contains ascorbic acid. For dispersing agent, polyvinylpyrrolidone or gelatin is preferred. Highly crystalline silver powder produced by the above-described method is preferred to be a crystallite diameter of 300 Å or more, an average particle diameter D 50 in the range from 0.5 µm to 10 µm, and a thermal shrinkage rate for the length direction after heating at 700°C in the range from -3% to 3%. For ratio D 90 /D 10 of the silver powder is preferred to be in the range from 2.1 to 5.0.