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:
Nov. 11, 1980
Filed:
Nov. 20, 1978
Applicant:
Inventor:
Brian A Cooke, Knotty Green, GB;
Assignee:
Imperial Chemical Industries Limited, London, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C23F / ; C23F / ;
U.S. Cl.
CPC ...
148 / ;
Abstract
A continuous process for coating ferrous or zinciferous metal substrates using an acidic coating solution of zinc phosphate in the presence of hydrogen peroxide wherein (a) the molar ratio ortho phosphate/zinc in solution is maintained in the range 0.5-3.7, and (b) the coating solution is replenished with hydrogen peroxide, replenishment feed (i) (comprising zinc, ortho phosphate and anion N.sup.n-), and replenishment feed (ii) (comprising alkali), the ratio of the quantities of (i) and (ii) being defined. The acid H.sub.n N has a pK.sub.a value not greater than 3.