Investigation of Life Extension and Optical Application for electroless Plating Using Co(II) Complex Ions as a Reducing Agent

摘要

Electroless silver plating using the oxidation reaction of Co(II) was investigated. Co(II) complexes with ammo- nia of amines were found to be an effective reducing agent for deposition. Plating reaction was promoted auto- catalytically without hydrogen evolution. Deposited silver films displayed excellent optical reflection properties like those of vacuum silver deposits. However, the deposition rate gradually decreased with the reaction time since Co (II)-amine complex ions are readily self oxidized in an air atmosphere and bath life diminished. Bath life can be prolonged with the prevention of Co(II) oxidation in a nitrogen atmosphere.