Method of coating luminescent powders, luminescent powders and coated object
US5744233A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 1995 |
| Grant date | Apr 28, 1998 |
| Priority date | — |
| Expiry date | Sep 8, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2993
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method of coating luminescent powders with a coating which comprises silicon dioxide, which method is characterized in that in a first step luminescent particles are dispersed in a solution containing one or more metallo-organic compounds of silicon and, optionally, metallo-organic compounds of further elements in a hydrous solvent mixture having a pH-value of 1<pH 5, whereafter the metallo-organic compounds are hydrolysed by adding ammonia. A further aspect of the invention relates to a luminescent powder having a coating composed of silicon oxide and at least one oxide of a further element selected from the group formed by aluminum, barium, lead, boron, magnesium, titanium, zinc, zirconium, cobalt, copper and iron. Another aspect of the invention relates to a coated object, such as a fluorescent screen or display screen for a cathode ray tube or lamp or for other electrical discharge tubes or lamps, in particular also color television display screens, which is coated with a luminescent powder coated in accordance with the invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.