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. 05, 1987
Filed:
May. 16, 1985
Makoto Yoshida, Tokyo, JP;
Kazuhiro Tano, Tokyo, JP;
Seizun Higuchi, Tokyo, JP;
Masato Nakamura, Tokyo, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
A zinc- or zinc alloy-hot-dipped, unpainted steel sheet having excellent black tarnish resistance, which has a coating of Ni, Co or a combination thereof deposited in an amount of from 0.1 to 15 mg/m.sup.2 on the zinc or zinc alloy plating layer of the sheet, and optionally a chromate layer on the deposited coating, is provided. The steel sheet is produced by immersing a zinc- or zinc alloy-hot-dipped steel sheet in an aqueous solution containing 1 to 20 g/l of Ni ions, Co ions or a combination thereof to deposit Ni, Co or a combination thereof in an amount of from 0.1 to 15 mg/m.sup.2 on the zinc or zinc alloy plating layer of the sheet, optionally followed by chromating in the usual manner.