Patent · US Expired

Scale inhibitors

US6395185B1 · kind B1 · utility

15Cited by
3References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 10, 2000
Grant dateMay 28, 2002
Priority date
Expiry dateOct 4, 2020

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:(I) 50-80% by weight of one or more weak acids;(II) 2-50% by weight of one or more strong acids;(III) 0-30% by weight of one or more monoethylenically unsaturated C4-C8 dicarboxylic acids; and(IV) 0-30% by weight of one or more monomethylenically unsaturated monomers polymerizable 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.