Process for the production of yellow to red pigments based on nitrides and oxidenitrides

US6379449B1 · kind B1 · utility

Assignee

• DMC, INC · DE

Inventors

• Martin Jansen · Bonn, DE
• Eberhard Gunther · Annaberg-Buchholz, DE
• Hans-Peter Letschert · Bonn, DE

Key dates

• Filing date: Feb 22, 2000
• Grant date: Apr 30, 2002
• Expiry date: Feb 22, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/60
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Nitride or oxidenitride based red to yellow pigments, such as tantalum(V) nitride and oxidenitrides containing tantalum may be produced by passing ammonia over nitridable metal compounds, in particular oxide compounds, at 700 to 1250° C. According to the invention, nitriding proceeds in a rotary tube or fluidised bed reactor in the presence of an oxide from the series SiO2, ZrO2, GeO2, SnO2, TiO2 and HfO2 under conditions under which this oxide is substantially not nitrided.