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:
Dec. 01, 2009
Filed:
May. 17, 2007
Changzai Chi, Hockessin, DE (US);
Michael Karl Crawford, Glen Mills, PA (US);
Kurt Richard Mikeska, Hockessin, DE (US);
Changzai Chi, Hockessin, DE (US);
Michael Karl Crawford, Glen Mills, PA (US);
Kurt Richard Mikeska, Hockessin, DE (US);
E.I. du Pont de Nemours and Company, Wilmington, DE (US);
Abstract
The invention is directed a composition represented by the chemical formula EuAFOwherein A is alkaline earth, 0.002≦x≦0.20, and 0≦y≦x; the composition exhibiting a luminescence spectrum characterized by peaks at 592±2 nm and 627±2 nm, wherein the ratio of the peak intensity at 592±2 nm to that at 627±2 nm is at least 5% larger than the corresponding peak intensity ratio at the same wavelengths of a first corresponding reference composition with the same value of x that has not been exposed to a temperature above 100° C., and wherein said ratio of the peak intensity at 592±2 nm to that at 627±2 nm is at least 5% smaller than the corresponding peak intensity ratio at the same wavelengths of a second corresponding reference composition with the same value of x that has been subject to heating to 900° C. for 6 hours.