Color stable red-emitting phosphors
US10793773B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 20, 2017 |
| Grant date | Oct 6, 2020 |
| Priority date | — |
| Expiry date | Sep 3, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10H20/8516
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A process for preparing a Mn+4 doped phosphor of formula I includes gradually adding a first solution comprising a source of M and HF and a second solution comprising a source of Mn to a reactor, in the presence of a source of A and an anion selected from phosphate, sulfate, acetate, and combinations thereof, to form a product liquor comprising the Mn+4 doped phosphor. The process also includes gradually discharging the product liquor from the reactor while volume of the product liquor in the reactor remains constant. A is Li, Na, K, Rb, Cs, or a combination thereof; M is Si, Ge, Sn, Ti, Zr, Al, Ga, In, Sc, Y, La, Nb, Ta, Bi, Gd, or a combination thereof; x is the absolute value of the charge of the [MFy] ion; and y is 5, 6 or 7.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.