Patent ID: 6638447
Filing Date: 2003-10-28
Classification: C01F,C01P,C09K

Abstract:
A method for preparing a rare earth activated alkaline earth metal fluorohalide stimulable phosphor represented by the following formula (I):Ba(1âˆ’x)M2(x)FBr(y)I(1âˆ’y):aM1, bLn, cOâ€ƒâ€ƒ(I) wherein M1 is at least an alkali metal selected from the group consisting of Li, Na, K, Rb and Cs; M2 is at least an alkaline earth metal selected from the group consisting of Be, Mg, Ca and Sr; Ln is at least one rare earth element selected from the group consisting of Ce, Pr, Sm, Eu, Gd, Tb, Tm, Dy, Ho, Nd, Er and Yb; and x, y, a, b and c are values meeting the following conditions:0&lE;x&lE;0.3, 0&lE;y&lE;0.3, 0&lE;a&lE;0.05 0the method comprising the steps of(a) preparing a reactant solution having a barium concentration of not less than 3.3 mol/l in a reaction vessel, (b) forming a precursor of the stimulable phosphor, (c) removing a solvent from a mother liquor, (d) separating the precursor from the mother liquor, and (e) calcining the separated precursor to make a rare earth activated alkaline earth metal fluorohalide stimulable phosphor.