Method of making green-emitting borate phosphors
US7846353B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2008 |
| Grant date | Dec 7, 2010 |
| Priority date | — |
| Expiry date | Aug 20, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K11/774
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
There is described a method for the preparation of a green-emitting terbium and cerium co-activated gadolinium magnesium pentaborate phosphor that utilizes a hydrated magnesium hexaborate as a boron source. The hydrated magnesium hexaborate preferably may be represented by the formula MgB6O10.XH2O where X is from 4 to 6, preferably 4.8 to 5.5, and more preferably about 5. The hydrated magnesium hexaborate is combined with oxides of Gd, Ce, and Tb, and at least one magnesium compound selected from MgCl2, MgF2, and MgO, and then fired in a slightly reducing atmosphere to form the phosphor. The method results in a greater homogeneity of the fired cake and subsequently a higher brightness. In addition, the method preferably requires only one firing step and provides very little or no sticking of the fired cake to the firing boats.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.