PREPARATION OF RARE EARTH-ACTIVATED ALKALINE EARTH METAL FLUORIDE HALIDE-BASED FLUORESCENT SUBSTANCE AND RADIOGRAPHIC IMAGE-CONVERTING PANEL USING RARE EARTH- ACTIVATED ALKALINE EARTH METAL FLUORIDE HALIDE-BASED FLUORESCENT SUBSTANCE OBTAINED BY THE METHOD

摘要

PROBLEM TO BE SOLVED: To obtain a fluorescent substance exhibiting excellent stimulable light emitting characteristics when used in a radiographic image recording/reproducing method by loosening a burned product having a specific composition by an aqueous solution containing a metal ion, subjecting the resultant slurry to wet classification to remove particles having a specific grain size or larger, subjecting the resultant to solid-liquid separation and drying the resultant solid product.;SOLUTION: A burned product represented by the formula is subjected a loosening treatment using an aqueous solution containing at least one metal ion selected from the group consisting of Li+, Na+, K+, Rb+, Cs+ and Ba2+. A mesh size employed in wet classification is not larger than 50 μm, preferably not larger than 30 μm. In the formula, MII is Sr, Ca or Mg; MI is a compound of Li, Na, K, Rb or CS; MIII is a trivalent metal compound of Al, Ga, In, Tl, Sc, Y, Cd or Lu; X is a halogen: Ln is a rare earth element such as Ce or the like; A is Al2O3, SiO2 or ZrO2; 0≤a≤0.3; 0≤b≤2; 0≤c≤2; 0≤d≤0.5; and 0≤x≤0.2.;COPYRIGHT: (C)2001,JPO