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. 12, 1978
Filed:
Apr. 27, 1977
Applicant:
Inventors:
Assignee:
Nippon Paint Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C23F / ;
U.S. Cl.
CPC ...
148 / ; 148 / ; 204D / ; 427345 ;
Abstract
In a method for phosphating the surface of a metallic substrate by treament with a phosphating solution comprising nitrite ions as the accelerator, an improvement wherein the supply of the nitrite ions to the phosphating solution is carried out by electrolytic reduction of nitrate ions present in the phosphating solution, whereby a desired concentration of nitrite ions in the phosphating solution is maintained without accumulation of alkali metal and/or ammonium ions unavailable for the phosphating and a uniform phosphate coating film having satisfactorily good coating properties is formed on said surface.