Patent ID: 7413805

Claim:
A method for preparing metallic particles for electrokinetic or electrostatic deposition comprising the steps of: contacting the metallic particles with a fully concentrated organic acid to form an organic acid surface film on the particles wherein the organic acid is selected from the group consisting of acetic acid, dicholoroacetic acid, trichloroacetic acid, propionic acid, maleic acid, glutaric acid, and methacryclic acid; and wherein the particles are solder metal particles; and contacting the metallic particles with a charge director medium which adheres to the organic acid surface film to impart an electrical charge to the particles; wherein the contacting the metallic particles with the fully concentrated organic acid comprises contacting the metallic particles with the fully concentrated organic acid in a ratio of weight of organic acid to weight of metallic particles in a range between about 0.2:1 to about 2:1.