Patent ID: 6852357

Claim:
A process for preparing a radiation image storage panel comprising a support and a phosphor film comprising a stimulable europium activated cesium bromide phosphor having the formula (I): CsBr.M I X−aM II X′ 2 +bM III X″ 3 :zEu (I) in which M I is at least one alkali metal element selected from the group consisting of Li, Na, K and Rb; M II is at least one alkaline earth metal element or divalent metal element selected from the group consisting of Be, Mg, Ca, Sr, Ba, Ni, Cu, Zn and Cd; M III is at least one rare earth element or trivalent metal element selected from the group consisting of Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga and In; each of X, X′ and X″ independently is at least one halogen selected from the group consisting of F, Cl, Br and I; and a, b, c and z are numbers satisfying the conditions of 0≦a<0.5, 0≦b<0.5, 0≦c<0.5, and 0<z<1.0, which comprises the steps of: depositing on the support a prismatic europium activated cesium bromide phosphor crystal layer on the support in a gas phase; and heating the crystal layer at a temperature of lower than 300° C. but not lower than 50° C. for a period of 1 to 8 hours in an inert gas atmosphere or an inert gas atmosphere containing a small amount of oxygen or hydrogen.