SURFACE-TREATING OF SULFURATED CALCIUM FLUORESCENT

摘要

The surface treating method of a calcium sulphide fluorescent material is characterized by (a) adding the fluorescent material (CaS:Eu) into an aq. potassium silicate soln., (b) regulating the mixt. with an acetic acid to pH 1.5-2.5, and then filtering and drying the fluorescent material, and (c) firing it at 500-900 deg.C for 1-3 hr. The content of a potassium silicate in the soln. is 0.1-10 wt.% w.r.t. 100 wt.% pure water. The surface-treated fluorescent material has an improved water resistance and a good luminescent property.