Abstract
In practical dyeing of anodic coating, it is very often evident that the proceeding of dyestuff adsorption is not satisfactory. It is apparent that the trouble is resulted from the blending of various kinds of ions in the dye bath.
The effects of blending of anodizing components and additives for controlling pH on dyestuff adsorption of anodic coating were studied.
As the results, it was found that the amount of adsorption was decreased with the increase in the amounts of anodizing components and additives. In particular, the effect was greater by blending of organic acids.
Furthermore, the effects of elimination of obstructive ions on the adsorbed amount and concentration of dyestuff were studied. When aluminum ions were precipitated as hydroxide, a larger amount of dyestuffs were adsorbed by aluminum hydroxide; and when sulfate ions were removed by precipitating as barium sulfate, the adsorption of dyestuffs was almost recovered.
