PHOSPHOR AND METHOD OF TREATING PHOSPHOR

摘要

A phosphor capable of being excited by ultraviolet rays in vacuum to thereby emit light, having changing of luminescent performance thereof with time suppressed so as to realize mercury-free fluorescent lamps or PDP capable of maintaining excellent luminescent performance for a prolonged period of time. In particular, a phosphor of oxide comprising particles having the region near the surface thereof modified so that the elemental composition of the region near the surface is in increasingly oxidized form as compared with that of the elemental composition of the internal region of particles. Alternatively, the region near the surface of particles has been modified so that halogens or chalcogens are contained in greater amounts in the elemental composition of the region near the surface than in the elemental composition of the internal region of particles. There is also provided a method of treating a phosphor, comprising exciting a gas containing reactive gas so as to form a gas atmosphere of high reactivity and exposing a phosphor to this gas atmosphere so that the region near the surface of phosphor particles is selectively modified.