Particulate fluorescent (Y1-xEux)2O3 material and process for its preparation

摘要

Fluorescent material which includes substantially spherical particles, each particle consisting of Y2O3 and of Eu2O3 and having a mean particle diameter of 90-210 nm and a narrow particle size distribution. The fluorescent material can be produced by heating an aqueous solution with a pH of 3 or below and containing an yttrium salt, a europium salt and urea at a temperature of at least 90 DEG C to coprecipitate YOHCO3 and EuOHCO3 in the form of particles with a mean particle diameter of 110-270 nm. The particles thus obtained are next calcined at a temperature of at least 600 DEG C to form spheres, each consisting of Y2O3 and of Eu2O3.