Method for preparing storage phosphors

Abstract

A method of preparing a stimulable phosphor layer comprising a phosphor composed of a host or matrix compound and a dopant or activator compound or element wherein a precipitate or inclusion having a size in the range from 10−3 μm up to 10 μm is present in said matrix compound, proceeds by the steps of (1) providing one or more crucibles containing precursor compounds for said host, said dopant and said precipitate, by increasing the temperature of said crucible(s) up to a temperature provoking evaporation of all of said precursor compounds as a vaporized latent phosphor cloud, (2) depositing said vaporized latent phosphor cloud in form of a layer onto a temperature controlled substrate, (3) followed by cooling said substrate, and (4) further annealing said phosphor layer at a temperature in the range from 35° C. up to 200° C., wherein said method is characterized by performing said annealing in an atmosphere having a water content of more than 10 g per m3 of dry air at the temperature at which annealing proceeds. In a further embodiment the temperature of the said substrate as presented in the annealing atmosphere when starting annealing, is lower than the dew point of water in said atmosphere.

Dependencies are inferred from the claim text.