Coated spherical SiO.sub.2 particles

US5846310A · kind A · utility

Assignee

• Merck Patent GmbH · DE

Inventors

• Tamio Noguchi
• Kazhisa Iwasa
• Ralf Anselmann · Munster, DE
• Martin Knapp · Dieburg, DE
• Manuela Loch · Merxheim, DE

Key dates

• Filing date: Apr 21, 1997
• Grant date: Dec 8, 1998
• Expiry date: Apr 21, 2017

Classification

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

Abstract

Spherical SiO.sub.2 particles with a size of from 5 to 500 nm coated at individual points with TiO.sub.2, Fe.sub.2 O.sub.3 or ZrO.sub.2 particles with a size of less than 60 nm. The coated SiO.sub.2 particles can be aftercoated with silanes or further metal oxides. The products obtained are used for pigmenting paints, printing inks, plastics and coatings or as sunscreen agents.