Process for producing electroluminescent phosphor with increased efficiency
US6387299B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 2, 2000 |
| Grant date | May 14, 2002 |
| Priority date | — |
| Expiry date | Aug 7, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K11/612
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An electroluminescent phosphor with an increased efficiency is created by blending a chloride flux, a copper source and a zinc sulfide to form a mixture and then heating the mixture for a period of time, cooling the mixture, and washing it with de-ionized water. The mixture is dried and milled to form cubic ZnS from hexagonal ZnS, forming a beginning uncoated ZnS:Cu,Cl electroluminescent phosphor. This beginning phosphor is added to other materials, including Ga2O3, forming a second step material (SSM). The SSM is placed into a first vessel, such as a plastic bottle, blended, sifted and then placed in a second inert reaction vessel that is then heated for a period of time. After cooling, the fired SSM is washed with de-ionized water, washed with acetic acid, again washed with de-ionized water to remove residual acid, washed with KCN and again with de-ionized water to remove residual KCN. The fired and washed SSM is then dried, filtered and sifted, producing a new phosphor with an increased efficiency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.