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:
Sep. 09, 2008
Filed:
Mar. 02, 2000
Jun Kawaguchi, Yokohama, JP;
Kazuhiro Ishikura, Aichi, JP;
Tomoyuki Manmi, Chigasaki, JP;
Henkel Kommanditgesellschaft Auf Aktien, Duesseldorf, DE;
Abstract
Electrolysis using a suitable electrolyte provides a completely nonsludging zinc phosphate conversion coating process that produces a high quality conversion coating in a very short time. The suitable electrolyte contains at least water, dissolved nitric acid, and dissolved zinc cations and optionally also contains m chemically distinct species of cations other than zinc and n chemically distinct species of anions other than anions derivable by ionization of phosphoric and nitric acids, each of m and n independently being zero or a positive integer. Preferably, the liquid composition contains as additive at least one selection from nitrous acid, permanganic acid, peroxysulfuric acid, hydrogen peroxide, chloric acid, perchloric acid, nitrobenzenesulfonic acid, hydroxylamine, starch/phosphoric acid esters, fluorine compounds, and salts of the preceding; and/or the metal substrate is subjected to cathodic electrolysis after the workpiece has been brought into contact with a weakly basic aqueous colloidal solution that contains titanium oxide, titanium hydroxide, and zinc phosphate.