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. 23, 1989
Filed:
Jun. 08, 1987
Hajime Ogata, Chiba-shi, Chiba, JP;
Hisatada Nakakouji, Chiba-shi, Chiba, JP;
Kyoko Hamahara, Chiba-shi, Chiba, JP;
Kazuo Mochizuki, Chiba-shi, Chiba, JP;
Toshio Ichida, Chiba-shi, Chiba, JP;
Other;
Abstract
A surface-treated steel strip adapted for electric resistance welding is prepared by forming a first layer of iron-nickel alloy on a steel strip, said first layer having a weight ratio of Ni/(Fe+Ni) in the range between 0.02 and 0.50 and a thickness of 10 to 5,000 angstroms, forming a second layer of tin or iron-tin-nickel alloy on said first layer by tin plating to a coating weight of 0.1 to 1 g/m.sup.2 of tin and optionally, causing the tin to reflow, and forming a third layer on said second layer by effecting an electrolytic chromate treatment, said third layer consisting essentially of metallic chromium and hydrated chromium oxide, wherein the electrolytic chromate treatment is carried out in a bath which contains an amount of a chromate compound to give 10 to 100 g/l of CrO.sub.3 and has a weight ratio of H.sub.2 SO.sub.4 /CrO.sub.3 in the range between 3/1000 and 1/100.