Patent · US Expired

Antimicrobial antifoam compositions and methods

US5169561A · kind A · utility

24Cited by
1References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 8, 1991
Grant dateDec 8, 1992
Priority date
Expiry dateApr 8, 2011

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01D19/0409
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A defoamer composition including a primary antifoam agent which includes a particulate-type material having a high surface area such as silica, a secondary antifoam agent for acting synergistically with the primary antifoam agent such as polydimethylsiloxane, a water carrier, and a quaternary ammonium salt silane compound which functions as an antimicrobial agent, fixed and adhered to the surface of the particulate material, in order that the defoamer composition be resistant to biological degradation due to the presence in the system of microorganisms. Methods of defoaming cationic, anionic, and nonionic surfactant produced foams are disclosed, as is a method of rendering silica hydrophobic.

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