A method for producing a very homogeneous alkaline earth metal - fluorine, chlorine phosphate - phosphor with apatite structure

摘要

1439319 Luminescent materials WESTINGHOUSE ELECTRIC CORP 11 Feb 1975 [22 Feb 1974] 5722/75 Heading C4S Chlorine is incorporated into an alkaline earth metal fluorophosphate material by heating the phosphate to 800-1300‹ C. in a Cl 2 atmosphere free of O 2 and H 2 O to form a homogeneous phosphor with a well controlled Cl to F ratio. The phosphate is preheated to 850‹ C. in air then flushed with inert gas. After heating the phosphor is cooled in inert gas. The Cl 2 is provided in a N 2 or A carrier and the apparatus must be leak free. The phosphate is prepared by precipitation and contains Sb or Eu or Mu and Sb activators. The Cl content is a function of the HCl concentration.