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:
Jan. 09, 1990
Filed:
Dec. 22, 1988
Anthony F Kasenga, Towanda, PA (US);
Leslie F Gray, Waverly, NY (US);
Thomas L Henson, Towanda, PA (US);
MacInnis, Martin B, Towanda, PA (US);
GTE Products Corporation, Stamford, CT (US);
Abstract
A method is disclosed for reproducibly producing manganese activated zinc silicate phosphor particles, which comprises dry blending a mixture of components consisting essentially of zinc oxide, silicic acid, a source of manganese, ammonium chloride, ammonium fluoride, tungstic oxide, and silica, wherein the Zu+Mn/Si mole ratio is from about 1.95 to about 2.02, wherein the silica is colloidal and has a surface area of from about 50 to about 410 m.sup.2 per gram, and wherein the colloidal silica makes up from about 0.01% to about 1.0% by weight of the mixture, and firing the resulting dry blend of components in a nitrogen atmosphere at a temperature of from about 1200.degree. C. to about 1300.degree. C. for a sufficient time to produce the phosphor wherein the phosphor exhibits reproducible brightness.