| 摘要 |
PURPOSE:To obtain a surface treating agent for Al causing no coloring and leaving no sexivalent Cr, by preparing an aqueous soln. contg. tervalent Cr ions, sexivalent Cr ions, phosphate ions and a water soluble acrylic polymer at specified concns. CONSTITUTION:A surface treating agent for Al and its alloys is obtd. by blending 1l water with 0.8-1.5g tervalent Cr ions, about 0.1-0.6g sexivalent Cr ions, 1.5-15g phosphate ions and 0.5-15g water soluble acrylic polymer. The ratio of the sexivalent Cr ions to the total Cr ions is 0.05-0.35. The tervalent Cr ions are ions from chromium hydroxide, chromium nitrate or the like, and the sexivalent Cr ions are ions from chromium trixoide or the like. The phosphate ions are ions from phosphoric acid or the lile. ''Acryzole A-1'' or the like is used as the water soluble acrylic polymer. |
