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. 25, 1976
Filed:
Jun. 18, 1975
Griff W Froman, St. John, IN (US);
Brian A Sok, East Chicago, IN (US);
Lenin F Martinez, Hammond, IN (US);
Albert R Mullins, Portage, IN (US);
Inland Steel Company, Chicago, IL (US);
Abstract
A process of making a one-side-only coated endless metal sheet in which a sheet initially having a protective metal coating, such as zinc, on both lateral surfaces thereof is subjected to an electrolytic treatment which removes the protective metal coating from only one side of the metal sheet by continuously passing the metal sheet through an electrolytic treating chamber containing as an electrolyte bath a strongly acidic aqueous solution, such as sulfuric acid, having a pH from about pH 0.1 to 2.0, and preferably about pH 1.0, or a strongly alkaline aqueous solution, such as sodium hydroxide, having a pH of at least about pH 11 and preferably above pH 11, with said metal sheet being guided between spaced anodic and cathodic electrodes immersed in said electrolyte bath so as to establish a cathodic current between said anodic electrode and the adjacent surface of said metal sheet which is made cathodic and establishing an anodic current from a second rectifier between said cathodic electrode and the adjacent surface of said metal sheet which is made anodic, and maintaining the anodic current at a current density level so as to maintain the surface of said metal sheet which is to remain coated completely cathodic and effects complete removal of said protective metal coating from the anodic surface during the period said sheet remains in said electrolytic treating chamber, and with the cathodic current maintained at a current density level below said anodic current density level but sufficiently high to neutralize the E.M.F. generated when the said protective metal coating is immersed in said electrolyte bath.