Method for improving a manganese activated zinc silicate phosphor

摘要

A new and improved method of treating a manganese activated zinc silicate phosphor is described. The method comprises heating a manganese activated zinc silicate phosphor powder having cations consisting essentially of zinc, silicon, manganese, and tungsten and having a 350 nm reflectance less than 80% and a 275 nm reflectance greater than 13.5% to a temperature of about 1225 DEG C. in air. The phosphor powder is then cooled to room temperature and wet milled in an acid solution. The phosphor powder is then separated from the acid solution washed in water and dried to form a dry phosphor powder having a 350 nm reflectance equal to or greater than 80% and a 275 nm reflectance equal to or less than 13.5%.