Patent · US Expired

Method for improving a manganese activated zinc silicate phosphor

US5039449A · kind A · utility

4Cited by
4References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 7, 1988
Grant dateAug 13, 1991
Priority date
Expiry dateNov 7, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K11/676
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A new and improved method of treating a manganese activated zinc silicate phosphor is described. The method comprises heating a manganese activated zinc silicate phosphor powder having cations consisting essentially of zinc, silicon, manganese, and tungsten and having a 350 nm reflectance less than 80% and a 275 nm reflectance greater than 13.5% to a temperature of about 1225.degree. C. in air. The phosphor powder is then cooled to room temperature and wet milled in an acid solution. The phosphor powder is then separated from the acid solution washed in water and dried to form a dry phosphor powder having a 350 nm reflectance equal to or greater than 80% and a 275 nm reflectance equal to or less than 13.5%.

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