Process for using tantalum (V) nitride as a pigment and the colored products produced thereby

US5569322A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Martin Jansen · Bonn, DE
• Hans-Peter Letschert · Bonn, DE
• Dietrich Speer · Hanau, DE

Key dates

• Filing date: Nov 10, 1994
• Grant date: Oct 29, 1996
• Expiry date: Nov 10, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2002/84
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

An improved method for producing tantalum (V) nitride by means of nitriding an oxidic tantalum (V) compound is described. The Ta.sub.3 N.sub.5 product obtained in accordance with this method may be used as a red coloring pigment, particularly for coloring plastics and varnishes. An improved color intensity can be achieved and/or the reaction time can be shortened using the process in accordance with the invention. The process includes nitriding tantalum (V) hydrated oxide with the composition of the formula Ta.sub.2 O.sub.5. aq with a hydrate content (i.e., aq content) in a range of 14 to 17% by weight. The nitridation preferably takes place in the presence of a fluxing agent such as ammonium carbonate or boric acid.