PROCESS FOR PRODUCING SURFACE-REGULATED ALUMINUM CAST

摘要

To provide a means for avoiding defective treated surface appearances or defective film performances after coating in techniques for nonchromate conversion treatment of aluminum castings even when a surface conditioning step with a strong alkali is carried out before the conversion treatment. [MEANS FOR SOLVING PLOBLEMS] A process for producing surface conditioned aluminum castings, comprising a step of applying to aluminum castings an alkaline surface conditioning liquid containing at least one organic builder and/or one chelating agent, wherein the alkaline surface conditioning liquid used in the step has a surface conditioning activity (CD; mol/l) in the range of 0.05 ‰¤ CD ‰¤ 2.3 and a coefficient of gloss (CE; g/mol) in the range of 2.8 ‰¤ CE ‰¤ 90.