Preparation of composition based on a rare earth sulfide containing at least one alkaline element for use in plastics, paints, lacquers, glazes, rubber, ceramics, paper, inks, cosmetic products and laminates

摘要

Process for preparing a composition based on a rare earth sulfide containing at least one alkali metal element comprises heating a mixture of at least one rare earth compound with an alkali metal phosphate or borate in the presence of at least one gas selected from H2S or CS2. Independent claims are included for: (1) A rare earth sulfide containing at least one alkali metal element prepared by the above process; (2) A colored pigment containing the rare earth sulfide; and (3) Compositions for coloring materials such as plastics, paints, lacquers, glazes, rubber, ceramics, paper, inks, cosmetic products and laminates.