Patent · US Expired

Copolymeric scale inhibitors for (Poly)phosphate scale control

US6114294A · kind A · utility

5Cited by
20References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 1, 1998
Grant dateSep 5, 2000
Priority date
Expiry dateMay 1, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC02F5/10
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

The invention relates to the inhibition of tripolyphosphate and pyrophosphate scales in aqueous systems involving adding to said aqueous system at least one copolymer comprising the following monomers in polymerized form: PA1 (I) 50-80% by weight of one or more weak acids; (II) 2-50% by weight of one or more strong acids; PA1 (III) 0-30% by weight of one or more monoethylenically unsaturated C.sub.4 -C.sub.8 dicarboxylic acids; and PA1 (IV) 0-30% by weight of one or more monomethylenically unsaturated monomers polymerisable with (I), (II) and (III); wherein the total of monomers (I), (II), (III), and (IV) equals 100% by weight of copolymer. The invention is particularly suited to the inhibition of tripolyphosphate and pyrophosphate scales which occur as a result of using low phosphate (STPP) containing detergent formulations.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.