Surface-modified silicon dioxides

US5429873A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Hans Deusser · Karlstein, DE
• Thomas Gobel · Lörrach, DE
• Jurgen Meyer · Aschaffenburg, DE
• Michael Gunther · Hamburg, DE
• Andreas Stubbe · Rodenbach, DE

Key dates

• Filing date: Oct 7, 1992
• Grant date: Jul 4, 1995
• Expiry date: Oct 7, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2995
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Surface-modified, pyrogenically produced silicon dioxide is obtained by placing a pyrogenically produced silicon dioxide in a know mixing device, spraying it with a chemical compound from the group: EQU CHF.sub.2 --CF.sub.2 --O--(CH.sub.2).sub.3 --Si(OCH.sub.3).sub.3 EQU CF.sub.3 --CHF--CF.sub.2 --O--(CH.sub.2).sub.3 --Si(OCH.sub.3).sub.3 EQU C.sub.4 F.sub.9 --CH.sub.2 --CH.sub.2 --Si(OCH.sub.3).sub.3 EQU C.sub.6 F.sub.13 --CH.sub.2 --CH.sub.2 --Si(OCH.sub.3).sub.3 with intensive mixing, subsequently mixing it and tempering the mixture obtained for a fairly long time.