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. 27, 1986
Filed:
Jan. 04, 1983
Masaaki Kamitani, Tokyo, JP;
Hidenori Tsuji, Kanagawa, JP;
Ebara-Udylite Co., Ltd., Tokyo, JP;
Abstract
The present invention includes an aqueous acidic chromate solution, suitable for forming colored chromate coatings on zinc-nickel alloy electrodeposits containing up to about 15% by weight nickel, which solutions have a pH within the range of about 1.3 to about 2.7, a hexavalent chromium concentration of at least 0.5 grams per liter, and preferably about 0.5 to about 100 grams per liter, and which contain sulfate in a weight ratio of SO.sub.4 :Cr.sup.+6 of about 0.025-1.5:1. The zinc-nickel alloy electrodeposits are preferably immersed in the chromating solution for a period sufficient to form the desired colored chromate coating. In some instances, a flash electrodeposit of zinc may be applied to the zinc-nickel alloy electrodeposit before it is immersed in the chromating solution. Alternatively, the zinc-nickel alloy electrodeposit may be immersed in the chromating solution and the solution electrolyzed, with the zinc-nickel alloy surface as the anode, at low current densities for a short period of time, after which, the electrolysis is discontinued and the zinc-nickel alloy surface is maintained in the chromating solution until the desired colored chromate film is formed.