Method of reducing the amount of cadmium capable of being extracted from calcined cadmium pigment powder by human gastric juices

US3977895A · kind A · utility

Assignee

• BASF Farben Fasern Aktiengesellschaft · DE

Inventors

• Rolf Berger · Neckartenzlingen, DE
• Wolfgang Kuch · Neidlingen, DE
• Hartmut Endriss

Key dates

• Filing date: Nov 26, 1975
• Grant date: Aug 31, 1976
• Expiry date: Nov 26, 1995

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2004/84
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

Acid-extractable cadmium in yellow, orange, or red cadmium pigments is reduced sharply without loss of tinctorial strength and other desirable pigment properties by suspending the pigment powder in water and adding approximately stoichiometric amounts of tin ions, preferably quadrivalent tin ions and sulfide ions, and recovering the solids from the mixture.