Highly-filled, aqueous metal oxide dispersion

US7704315B2 · kind B2 · utility

Assignee

• Degussa AG · DE

Inventors

• Monika Oswald · Hanau, DE
• Corinna Kissner · Hanau, DE
• Roland Weiss · Iserlohn, DE
• Andreas Lauer · Kirchhain, DE

Key dates

• Filing date: Jul 19, 2005
• Grant date: Apr 27, 2010
• Expiry date: Aug 3, 2026

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B2235/602
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Aqueous dispersion containing a metal oxide powder with a fine fraction and a coarse fraction, in which—the metal oxide powder is silicon dioxide, aluminum oxide, titanium dioxide, zirconium dioxide, cerium oxide or a mixed oxide of two or more of the aforementioned metal oxides,—the fine fraction is present in aggregated form and has a mean aggregate diameter in the dispersion of less than 200 nm,—the coarse fraction consists of particles with a mean diameter of 1 to 20 μm, —the ratio of fine fraction to coarse fraction is 2:98 to 30:70, and—the content of metal oxide powder is 50 to 85 wt. %, referred to the total amount of the dispersion. The aqueous dispersion is produced by a process comprising the steps:—production of a fine fraction dispersion by dispersing the pulverulent fine fraction in water by means of an energy input of at least 200 KJ/m3?, and—introducing the coarse fraction in the form of a powder into the fine fraction dispersion under dispersing conditions at a low energy input. Process for the production of molded articles using the dispersion.