Process for preparing rare earth oxide phosphors
Abstract
Abstract A PROCESS FOR INCREASING AND CONTROLLING THE PARTICLE SIZE OF A RARE EARTH OXIDE PHOSPHOR IS DISCLOSED. THE PROCESS COMPRISES FORMING A MIXTURE OF A FLUXING AGENT AND A RARE EARTH SOURCE IN WEIGHT RATIOS OF FROM ABOUT 4:96 TO ABOUT 25:75, RAISING THE TEMPERATURE OF THE MIXTURE TO AT LEAST ABOUT 1100*C. AND HOLDING THE MIXTURE ABOVE ABOUT 1100*C. FOR A SUFFICIENT TIME TO FORM A RARE EARTH OXIDE PHOSPHOR HAVING A PARTICLE SIZE OF AT LEAST ABOUT 4 MICRONS. THE FLUXING AGENTS SUITABLE ARE THE ALKALI METAL HYDROGEN SULFATES, ALKALI METAL PYROSULATES AND MIXTURES THEREOF. THE PARTICLE SIZE OF THE PHOSPHOR MATERIAL IS DEPENDENT UPON THE AMOUNT OF FLUXING AGENT USED WITHIN THE SUITABLE RATION OF FLUXING AGENT TO RARE EARTH SOURCE.
Inventors
- 👤 John L Ferri
- 👤 James E Mathers
Bibliographic Details
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