Patent · US Expired

Method of making haloapatite phosphors

US7255812B2 · kind B2 · utility

1Cited by
2References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 28, 2004
Grant dateAug 14, 2007
Priority date
Expiry dateOct 3, 2025

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K11/7478
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A method of making a haloapatite phosphor having a general formula represented by (Ca(1−x−y)MnxSby)5(PO4)3(F(1−z−y)ClzOy), where 0<x<0.05, 0.004<y<0.01, and 0<z<0.1. is provided. The method involves (a) formulating a blend of ingredients to make the haloapatite phosphor, the ingredients including CaHPO4 as a primary source of calcium and phosphorus, (b) partially substituting an amount of an equimolar combination of an ammonium phosphate compound and calcium carbonate for an equal number of moles of CaHPO4 in the formulation, (c) combining the ingredients in their formulated amounts to form the blend, and (d) firing the blend to form the haloapatite phosphor. The partial substitution has been found to increase the 100-hour brightness of the haloapatite phosphors.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.