ALKALINE EARTH METAL PHOSPHOR, WAVELENGTH CONVERSION MEMBER AND LIGHT-EMITTING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an alkaline earth metal phosphor that hardly causes humidity deterioration and can maintain high luminous efficiency over a long period of time.SOLUTION: The alkaline earth metal phosphor (1,1A) comprises a phosphor particle (2) containing an alkaline earth metal and a coating film (3) covering the surface of the phosphor particle and containing an oxide of at least one element selected from the group consisting of silicon, titanium, aluminum, magnesium and niobium. The alkaline earth metal phosphor is present in voids in the inside of the coating film and comprises a filler (4) containing at least one selected from the group consisting of a sulfate of an alkaline earth metal, a carbonate of the same, a phosphate of the same and a fluoride of the same. The amount of the filler present in the inside of the coating film is larger in an inner surface (3b) in contact with the phosphor particle than in an outer surface (3a) of the coating film.SELECTED DRAWING: Figure 1