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. 25, 1990
Filed:
Feb. 21, 1989
Applicant:
Inventors:
Romano G Pappalardo, Sudbury, MA (US);
Thomas E Peters, Chelmsford, MA (US);
Roger B Hunt, Jr, Medfield, MA (US);
Assignee:
GTE Laboratories Incorporated, Waltham, MA (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
B05D / ; B05D / ;
U.S. Cl.
CPC ...
427 67 ; 427 70 ; 427237 ; 427255 ; 4274192 ;
Abstract
The lumen maintenance of fluorescent lamps containing yttrium vanadate phosphors is markedly improved by the presence of a protective oxide layer for the phosphor. The protective oxide layer is produced by evaporating aluminum isopropoxide, in a vacuum, over phorphor particles forming a continuous aluminum isopropoxide over the phosphor particles. The isopropoxide coating is subsequently oxidized by lehring the phosphor at a temperature from about 500.degree. C. to 625.degree. C. forming an alumina coating on the phosphor particles.