Process of preparing porosity-free calcium halophosphate phosphors
Abstract
Abstract A process for the production of relatively porosity-free calcium halophosphate phosphors activated such as with antimony and manganese. The process involves using either calcium pyrophosphate, Ca2P2O7, or tribasic calcium ortho-phosphate, Ca3(PO4)2, as the phosphate ingredient in a batch of ingredients containing the constituent elements of the desired phosphor. The batch is fired at an elevated temperature for a time sufficient to produce the phosphor. The extent of freedom from porosity of the phosphor can be characterized by the slope of a line obtained by plotting a graph of log I/Io versus mg/mm2 wherein I/Io is the ratio of the intensity of light transmitted in a forward direction through a sample of the phosphor in particulate form suspended in a liquid of essentially matching index of refraction to the intensity of the light transmitted without the phosphor, and mg/mm2 is the concentration of the phosphor measured in milligrams of phosphor per square millimeter of light beam. A slope less negative than -2.7 mm2/mg is within the invention.
Inventors
- 👤 R Hickok
- 👤 T Vincent
- 👤 A Friedman
Bibliographic Details
Claims Analysis
Total Claims: 1References Cited (Backward Citations)
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