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:
Mar. 09, 1999
Filed:
Sep. 27, 1996
Koji Kitamura, Osaka, JP;
Shozo Oshio, Nara, JP;
Teruaki Shigeta, Osaka, JP;
Shigeru Horii, Osaka, JP;
Takeshi Nishiura, Osaka, JP;
Tomizo Matsuoka, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An alkaline earth metal compound containing no fluorine atoms in its molecules, a rare earth compound containing no fluorine atoms in its molecules, and an aluminum compound containing no fluorine atoms in its molecules are fired in a high-temperature reducing atmosphere ranging from 1600.degree. to 2000.degree. C., so that an aluminate phosphor, the particle diameter and shape thereof are controlled, is provided. A mixture of 22 wt % of barium carbonate, 11 wt % of basic magnesium carbonate, 65 wt % of spherical alpha-alumina of 10 .mu.m diameter and 2 wt % of europium oxide is fired in a mixed gas atmosphere consisting of gaseous hydrogen of 5 volume % and gaseous nitrogen. The temperature is raised at 400.degree. C./hr, and lowered at 400.degree. C./hr after firing for two hours at 1700.degree. C. As a result, a spherical aluminate phosphor of 10 .mu.m diameter, which is expressed by formula (Ba.sub.0.9,Euo.sub.0.1)MgAl.sub.10 O.sub.17 is obtained.