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:
Oct. 04, 1977
Filed:
Jul. 20, 1976
Ciba-Geigy Corporation, New York, NY (US);
Abstract
A method of treating an aqueous system to inhibit the corrosion of metals in contact therewith and/or inhibit the deposition of scale therefrom comprising adding to the aqueous system a minor proportion of a compound of the formula: ##STR1## wherein n is 0 or 1 and when n is O, R.sub.3 and R.sub.4 are the same or different and each is hydrogen, an alkyl group having from 1 to 4 carbon atoms, a benzyl, allyl, --CH.sub.2 PO.sub.3 H.sub.2 -- or --CHCOOH.CH.sub.2 COOH group or a group of formula ##STR2## wherein R.sub.5 is hydrogen, a methyl, --CH.sub.2 COOH or --CH.sub.2 CH.sub.2 COOH group and Z is a group --COOH or --PO.sub.3 H.sub.2, with the proviso that when Z is a PO.sub.3 H.sub.2 group then R.sub.5 is hydrogen or methyl, and when n is 1, R.sub.1 and R.sub.2 are the same or different and each is hydrogen, or a methyl or phenyl residue and R.sub.3 is hydrogen and R.sub.4 is hydrogen, an alkyl group having from 1 to 4 carbon atoms or a --CH.sub.2 CH.sub.2 COOH group, or R.sub.3 and R.sub.4 together may form a methylene group .dbd.CH.sub.2.