Phosphor and process for preparing same
AssigneeAgence Nationale de Valorisation de la Recherche
InventorsAlain Vedrine, Jean-Claude Gacon, Georges Boulon, Danielle Trottier
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Abstract
A phosphor of the fluoride type mixed with potassium and yttrium doped with divalent europium, characterized in that it responds to the formula K.sub.(1-x) Eu.sub.x Y.sub.3 F.sub.10+x wherein x is less than 0.06. The invention also concerns a process for preparing this product which may be used in a laser.
Claims6
A divalent europium activated potassium yttrium fluoride phosphor which corresponds to the formula:
- K.sub.(1-x) Eu.sub.x Y.sub.3 F.sub.10+x
- wherein x is positive and up to 0.06, the said phosphor emitting an intense monochromatic emission centered about 3585 Angstroms when excited by ultraviolet radiation at temperatures below 400.degree. K.
A process for preparing a divalent europium activated potassium yttrium fluoride phosphor which corresponds to the formula K.sub.(1-x) Eu.sub.x Y.sub.3 F.sub.10+x, wherein x is positive and up to 0.06, said phosphor emitting an intense monochromatic emission centered about 3585 Angstroms when excited by ultraviolet radiation at temperatures below 400.degree. K., comprising:
- mixing in potassium fluoride, yttrium trifluoride and a divalent europium based doping agent in amounts corresponding to said formula, the said doping agent being selected from the group consisting of europium difluoride and a mixture of metallic europium and europium trifluoride in stoichiometric proportions;
- heating said resultant mixture at 900.degree. C. for 15 hours under reduction conditions;
- and
- then permitting the mixture to slowly cool thus obtaining the phosphor.
Dependencies are inferred from the claim text.