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:
Jun. 11, 1991
Filed:
Dec. 19, 1989
Costas C Lagos, Danvers, MA (US);
GTE Products Corporation, Danvers, MA (US);
Abstract
An improved method for preparing a phosphor is disclosed. The method of the invention includes preparing a solution comprising the non-oxygen elements of the phosphor in molar proportions equal to the respective molar proportions of the non-oxygen elements in the phosphor; precipitating the non-oxygen elements from the solution through the addition of a precipitating agent; spray drying the solution including the precipitate to form a spray dried powder; and firing the spray dried powder in a single firing step. The single firing step of the method comprises (a) increasing the temperature of the spray dried powder at an even and controlled rate from room temperature to a firing temperature sufficiently high to convert the spray dried powder to the phosphor; and (b) maintaining the temperature of the spray dried powder at the firing temperature for a period of time sufficient to produce the phosphor. The method is particularly useful in the preparation of Eu.sup.2+ -activted strontium borate phosphor.