Defoaming composition and method of defoaming aqueous solutions or dispersions

US4028218A · kind A · utility

Assignee

• Th. Goldschmidt. AG · DE

Inventors

• Hans-Ferdi Fink · Essen, DE
• Herwig Fritsch · Gladbeck, DE
• Gotz Koerner · Essen, DE
• Gerd Rossmy · Werden, DE
• Gunter Schmidt · Houghton, US

Key dates

• Filing date: Oct 18, 1974
• Grant date: Jun 7, 1977
• Expiry date: Oct 18, 1994

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S8/01
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

In the disclosed method of preventing the formation of foam and destroying existing foam in an aqueous solution or dispersion, an effective amount of a composition comprising about 0.2 to 7.5 percent by weight of highly disperse silica or alumina with the balance being methylpolysiloxanepolyoxyalkylene mixed block polymer consisting essentially of PA1 A. about 10-60 percent by weight of methylpolysiloxane; PA1 B. with the balance polyoxyalkylene, > 80-100 percent by weight of the polyoxyalkylene block consisting of oxypropylene units, Is added to the solution or dispersion. The application also discloses defoaming preparations or compositions of finely disperse silica or alumina and methylpolysiloxane-polyoxyalkylene mixed block polymer which may be diluted in oily substances. The preparation may optionally comprise non-ionogenic emulsifier of an HLB value of 8 to 14.