高光沢非シアン化銀めっき浴の分極挙動におよぼすチオ硫酸ナトリウム添加の影響

抄録

When sodium thiosulfate is added at a 2:1 ratio to the sodium sulfite system electrolyte, the silver dissolution current at peak printing is increased in the anodic polarization curve. At the same time, the current density in all potentials increased. In the cathodic polarization curves, the electrodeposition potential becomes lower when this reagent was added than for that in the pure sulfite system bath. The limiting current density is reduced due to the increase in polarization. In addition, the anodic reaction, mainly due to the complex action and increase in the concentration of sodium thiosulfate, reacts more actively with anodic oxidation dissolution, which results in destroying the passivated film, therefore making the silver surface appear to be a pure silver crystal surface.
Therefore, the changes in the concentration of silver ions, pH and the solution are reduced in the soidum thiosulfate system bath.