| 摘要 |
PURPOSE:To decrease the quantity of consumption of supply agent and forming quantity of insoluble phosphate group sludge, by adding Zn(NO2)2 or Ca(NO2)2 as reaction accelerator for supply at the time of treating the surface of steel by phosphate solution containing Zn<2+> or Zn<2+> and Ca<2+>. CONSTITUTION:On occasion of forming the film of phosphate on the surface of steel by using the phosphate solution containing Zn<2+> or Zn<2+> and Ca<2+>, more than one kind of Zn(NO2)2 or Ca(NO2)2 are added to the above solution as reaction accelerator for supply in the state of solid or liquid. Hereby, concentration of treating liquid by electric conductivity is able to control by automatic control accurately and also, easily. |
