Method for producing cadmium free green emitting CRT phosphor
US4925593A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1989 |
| Grant date | May 15, 1990 |
| Priority date | — |
| Expiry date | Jan 27, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K11/642
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A cadmium-free cathodoluminescent phosphor composition consists essentially of zinc sulfide activated with from about 0.019% by weight to about 0.024% by weight of copper and from about 0.01% by weight of about 0.02% by weight of aluminum wherein the emission of the phosphor upon stimulation by cathode rays has CIE values of x of from 0.287 to 0.291 and y from 0.616 to 0.620. The process involves solid state heating of the various raw materials wherein a first relatively pure zinc sulfide and a second zinc sulfide containing chloride ions are mixed with the appropriate levels of and alkali metal chloride and sources of copper and aluminum activators and then heated in a nitrogen-carbon disulfide atmosphere for about 3 hours at 1775.degree. C. to about 1825.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.