Preparation of radiation image storage panel

A process for the preparation of a radiation image storage panel having a phosphor layer which comprises a stimulable phosphor comprising a matrix component and an activator component, which comprises the steps of:

• forming on a substrate a lower prismatic crystalline layer consisting essentially of the matrix component by vapor deposition;
• and
• forming on the lower prismatic crystalline layer an upper prismatic crystalline layer comprising the matrix component and the activator component by vapor deposition, under the conditions that a ratio of thickness between the lower prismatic crystalline layer and the upper prismatic crystalline layer would be in the range of 1:100 to 1:1, and that a concentration of the activator component in a portion of from a bottom surface of the lower prismatic crystalline layer to depth of 99/100 based on a total depth of the lower and upper prismatic crystalline layers and a concentration of the activator component in a portion of from the upper surface of the upper prismatic crystalline layer to depth of 1/100 based on the total depth of the lower and upper prismatic crystalline layers satisfy the condition of 0≦p/q<0.1, wherein p stands for the concentration in the portion of from the bottom surface to depth of 99/100, and q stands for the concentration in the portion of from the upper surface to depth of 1/100.