| 摘要 |
A process is disclosed for preparing a single phase M'YTaO4:Nb X-ray phosphor which comprises firing a uniform milled mixture consisting essentially of the components of Y2O3, Ta2O5, and Nb2O5 in an amount equal to the stoichiometric amounts to form the phosphor, with a flux consisting essentially of lithium sulfate and potassium sulfate in a mole ratio of about 80 to 20, wherein the flux makes up from about 25% to about 50% by weight of the mixture. The firing is done by heating in a furnace to a temperature of from about 1200 DEG C. to about 1300 DEG C. at a heating rate of from about 1.0 DEG C. per minute to about 1.5 DEG C. per minute and maintaining the temperature for about 10 to 14 hours to react the components and produce a fired material containing luminescent material. The material is cooled by turning off the heat to the furnace and allowing the fired material to remain in the furnace until the temperature in the furnace is no higher than about 300 DEG C. The material is washed, dried, and classified to obtain a -325 mesh particle size. The phosphor essentially free of the impurity phases of Y3TaO7, the freedom from the impurity phases resulting in an improvement in brightness over phosphors produced by prior methods and having the impurity phases present.
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