PURPOSE: To obtain a fluorescent substance, having a high brightness with long afterglow, capable of readily carrying out the fogging check by irradiation of ultraviolet rays and suitable as cathode ray tubes, etc., by coating the surfaces of specific manganese-activated zinc phosphate fluorescent substance particles with particles capable of emitting light by irradiation of the ultraviolet rays.

CONSTITUTION: The objective fluorescent substance is obtained by coating the surfaces of manganese-activated zinc phosphate fluorescent substance particles expressed by the chemical formula Zn3(PO4)2: Mn with preferably 1-10wt.% particles, composed of a europium-activated rare earth oxide fluorescent substance and capable of emitting light by irradiation of ultraviolet rays.