Patent ID: 6649081
Filing Date: 2003-11-18
Classification: C23F,C23G

Abstract:
An aqueous liquid composition that is suitable either as a concentrate, after dilution with water, or both as a concentrate and after dilution with water, for Deoxidizing etching of aluminum surfaces by contact therewith, said composition comprising water and:(A) a component of dissolved acid wherein component (A) consists of a concentration of nitric acid that is from about 44 to about 70 g/l; (B) a component of dissolved fluoroborate anions present in a concentration that is from about 1.50 to about 3.0 g/l and is derived from fluoroboric acid, its salts, or both; the ratio of the concentration of dissolved fluoroborate anions to dissolved nitric acid in the composition is from 0.029:1.0 to 0.055:1.0; (C) a component of dissolved oxidizing agent that is not part of either of components (A) or (B) as recited next above; wherein component (C) consists of from about 25 to about 40 g/l of hydrogen peroxide; the concentration of hydrogen peroxide has a ratio to the concentration of fluoroborate anions that is from about 12.0:1.0 to about 20:1.0; the concentration of hydrogen peroxide has a ratio to the concentration of nitric acid that is from about 0.50:1.0 to about 0.90:1.0; the composition also comprises propylene glycol in a ratio to hydrogen peroxide, in the same concentration units, that is from about 0.13:1.0 to about 0.30:1.0; and (D) a component of dissolved organic molecules that is not part of any of components (A)-(C) as recited next above, comprising from about 0.46 to about 0.88 g/l of benzotriazole.