Aluminium oxide powder, dispersion and coating composition

US8197791B2 · kind B2 · utility

Assignee

• EVONIK DEGUSSA GMBH · DE

Inventors

• Kai Schumacher · Hofheim, DE
• Martin Moerters · Rheinfelden (Baden), DE
• Juergen Flesch · Rayong, TH
• Marcus Von Twistern · Mobile, US
• Volker Hamm · Bad Säckingen, DE
• Matthias Schmitt · Nuremberg, DE
• Harald Alff · Alzenau, DE
• Roland Schilling · Alzenau, DE

Key dates

• Filing date: Dec 20, 2005
• Grant date: Jun 12, 2012
• Expiry date: Jun 26, 2028

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/129
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Aluminum oxide powder in the form of aggregates of primary-particles, which has a BET surface area of from 10 to 90 m2/g and comprises as crystalline phases, in addition to gamma-aluminum oxide and/or theta-aluminum oxide, at least 30% of delta-aluminum oxide. It is prepared by vaporizing aluminum chloride and burning the vapor together with hydrogen and air, the ratio of primary air/secondary air being 0.01 to 2, the exit speed vB of the reaction mixture from the burner being at least 10 m/s, the lambda value being 1 to 4, the gamma value being 1 to 3 and the value of gamma*vB/lambda being greater than or equal to 55. Dispersion comprising the aluminum oxide powder. Coating composition comprising the dispersion.