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:
Mar. 20, 1979
Filed:
Jun. 16, 1977
Applicant:
Inventors:
Helmold von Plessen, Kelkheim, DE;
Edmund Bassler, Schwaikheim, DE;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C23F / ;
U.S. Cl.
CPC ...
422-7 ; 203-7 ; 203 86 ; 252387 ; 422-8 ;
Abstract
Gray cast iron can be protected against corrosion in boiling concentrated sulfuric acid if the acid contains precious metals such as gold or the metals of the platinum group. It is possible to add small amounts of compounds of the precious metal to the acid or to bring both the gray cast iron and the acid into contact with metal sheets or wires of the precious metal. It is also possible to use small amounts of the precious metal as an alloying element of the gray cast iron.