The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 07, 1996
Filed:
Mar. 28, 1994
Toshiaki Shimakura, Neyagawa, JP;
Takeyasu Ito, Chiba, JP;
Yuichi Yoshida, Yawata, JP;
Masayuki Kamimura, Ichikawa, JP;
Satoshi Ikeda, Yamato, JP;
Miyuki Shimada, Osaka, JP;
Nippon Paint Co., Ltd., Osaka, JP;
Abstract
Disclosed is an acidic cleaning aqueous solution for aluminum and aluminum alloy and a process for cleaning the same, intended to execute acidic cleaning without using harmful fluoride and chloride ions. The oxidation-reduction potential of a cleaning bath is controlled to be at 0.5 to 0.8 V (vs. Ag-AgCl). The cleaning bath is obtained by diluting an acidic cleaning aqueous solution for aluminum and aluminum alloy to a predetermined volume. The acidic cleaning aqueous solution contains specified amounts of at least one of inorganic acids, Br.sup.- ions and oxidized metal ions, with the addition of a surfactant and oxidizing agent if necessary. It is thus possible to present a uniform etching effect irrespective of low temperature (below 60.degree. C.) without containing fluoride ions and chromic ions within the acidic cleaning aqueous solution. Br.sup.- also has an effect of inhibiting the oxidation-decomposition reaction of the surfactant arising from the oxidizing agent and oxidized metal ions, thereby obtaining a long-life acidic cleaning aqueous solution.