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:
May. 14, 2002
Filed:
Aug. 02, 2000
Butchi Reddy Vaddi, Sayre, PA (US);
Shellie K. Northrop, Sayre, PA (US);
Osram Sylvania Inc., Danvers, MA (US);
Abstract
An electroluminescent phosphor with an increased efficiency is created by blending a chloride flux, a copper source and a zinc sulfide to form a mixture and then heating the mixture for a period of time, cooling the mixture, and washing it with de-ionized water. The mixture is dried and milled to form cubic ZnS from hexagonal ZnS, forming a beginning uncoated ZnS:Cu,Cl electroluminescent phosphor. This beginning phosphor is added to other materials, including Ga O , forming a second step material (SSM). The SSM is placed into a first vessel, such as a plastic bottle, blended, sifted and then placed in a second inert reaction vessel that is then heated for a period of time. After cooling, the fired SSM is washed with de-ionized water, washed with acetic acid, again washed with de-ionized water to remove residual acid, washed with KCN and again with de-ionized water to remove residual KCN. The fired and washed SSM is then dried, filtered and sifted, producing a new phosphor with an increased efficiency.