Abstract: Long decay luminescent materials having improved long decay time and improved high brightness is represented by the formula asSr.sub.0.9995 .about..sub.0.998 Eu.sub.0.0005 .about..sub.0.002)Al.sub.2 O.sub.4 .multidot.(Sr.sub.0.9995 .about..sub.0.998 Eu.sub.0.0005 .about..sub.0.002)O .multidot.n(Al.sub.1-a-b B.sub.b Dy.sub.a).sub.2 O.sub.3in it a=0.0005.about.0.0002, b=0.0001.about.0.35, n=1.about.8 and the method for manufacturing the long decay luminescent materials is characterized in heating the raw materials as SrCo.sub.3, .alpha. type alumina, .gamma. type alumina, boron-containing compound, Eu.sub.2 O.sub.3 and Dy.sub.2 O.sub.3 gradually from 400.degree. C. up to 1250.degree. C..about.1600.degree. C. during 7.about.10 hours, firing it at 1250.degree. C..about.1600.degree. C. for 3.about.5 hours and then cooing it gradually from 1250.degree. C..about.1600.degree. C. down to 200.degree. C. during 7.about.
Type:
Grant
Filed:
July 21, 1997
Date of Patent:
December 29, 1998
Assignees:
Beijing Hongye Coating Materials Company, Chemitech, Inc.