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:
Dec. 24, 1996
Filed:
Apr. 19, 1995
Applicant:
Inventors:
Brian Greaves, Runcorn, GB;
Stephen C Poole, Newton-Le-Willows, GB;
Chih M Hwa, Palatine, IL (US);
Joseph C Fan, Lake Zurich, IL (US);
Assignee:
W. R. Grace & Co.-Conn., New York, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C23F / ; C23F / ;
U.S. Cl.
CPC ...
252392 ; 252393 ; 252395 ; 25238954 ; 25218828 ; 422 12 ; 422 13 ; 422 16 ; 422 19 ;
Abstract
A method of treating an aqueous system is described which comprises incorporating in the system a hydroxylamine derivative of the general formula: ##STR1## wherein each of R.sub.1, R.sub.2 and R.sub.3 which may be the same or different represents hydrogen, alkyl of 1 to 8 carbon atoms or aryl or a water soluble salt thereof or a precursor thereof, and a tannin in a weight ratio of at least 2:1. This is particularly useful for boiler water systems.