抄録
Observation of Microscopic structure of the cross section of bright copper deposits leads to the following conclusions:
Without brightener, the crystal mostly grows parpendicular to the base and the band structure does not appear, even though the periodic reverse process, periodic alternate current process, or periodic intermittent process is applied. With brightener, however, the band structure appear, especially when each of the above processes is applied its clearness increases.
The effect of plating conditions on band structure is that the clearness increases with an increase of brighteners, free cyanide, potassium salt and C. D., which means alternate deposits of copper and brightener.
The appearance of band structure, however, does not necessarily bring about brightness. The band structure is nothing but a phenomenon caused by brightening action and the section of the bright deposit shows structure that seem to retard the growth parpendicular to the base.
