A PIGMENT COMPRISING ZINC SELENIDE OR SELENOSULPHIDE

摘要

A pigment comprises a material comprising crystalline zinc selenide or selenosulphide below 40% of whose zinc atoms and optionally some of whose selenium and sulphur atoms are substituted to lower the band gap energy but retain the essential crystal lattice of the zinc selenide or selenosulphide, the resulting lattice containing a greater percentage of zinc atoms than of sulphur atoms. The material wherein at least 0.1% of the zinc atoms are substituted is a new composition of matter.