The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 30, 2007
Filed:
Mar. 30, 2005
Xianzhong Chen, Sayre, PA (US);
Shellie K. Northrop, Sayre, PA (US);
Xianzhong Chen, Sayre, PA (US);
Shellie K. Northrop, Sayre, PA (US);
Osram Sylvania Inc., Danvers, MA (US);
Abstract
An electroluminescent phosphor powder includes copper-activated zinc sulfide particles that have a size distribution with a D50 value of no more than 10 μm, where no more than 25% of the particles have a size greater than about 15 μm and/or a 24-hr brightness of at least 15 footlamberts. These particles are made by a method that includes first firing copper-doped zinc sulfide mixed with zinc oxide, sulfur and a chloride-containing flux, rapidly cooling the mixture to below 100° C., and then mulling and second firing the mixture to provide a powder. The powder can then be elutriated to provide the electroluminescent powder with a narrow particle size distribution (more than 90% between about 5 and 15 μm). The elutriating step can be avoided (albeit with a slightly wider size distribution) by more tightly controlling the first firing temperature.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile