| 摘要 |
PURPOSE: To provide an electrolytic producing method of tin sulfate and bismuth sulfate for tin-bismuth alloy plating. CONSTITUTION: Tin or bismuth is dissolved in a sulfuric acid electrolyte by using an electrolytic cell having an anode and cathode, which are separated by an anion exchange membrane or the anion exchange membrane and a cation exchange membrane, using a sulfuric acid solution as the electrolyte, using tin or bismuth as an anode and impressing DC voltage between the anode and a cathode. As a result, uranium or thorium of radioisotopes is removed and the count number of a radioactiveα-particle in a film plated by using the tin or bismuth is suppressed to <=0.1CPH/cm<2> .
|
