Compositions – Inorganic luminescent compositions – Compositions containing halogen; e.g. – halides and oxyhalides
Patent
1988-03-29
1989-01-03
Cooper, Jack
Compositions
Inorganic luminescent compositions
Compositions containing halogen; e.g., halides and oxyhalides
C09K 1164
Patent
active
047955880
ABSTRACT:
Method of preparing a luminescent Eu.sup.2+ activated strontium aluminate defined by the formula Sr.sub.4 Al.sub.14 O.sub.25 :Eu.sup.2+ in which per mol of the Al present a combination of between 0.1 and 5 mol % of B.sub.2 O.sub.3 or compounds yielding B.sub.2 O.sub.3 upon an increase of temperature, and between 0.1 and 10 mol % of at least one of the fluorides and/or chlorides of Ba, Sr, Cs and/or Al and/or RbCl as a flux to a mixture comprising SrO, Al.sub.2 O.sub.3 and Eu.sub.2 O.sub.3 or compounds yielding these oxides upon an increase of temperature, whereafter the mixture is subjected to a first heat treatment in a weekly reducing atmosphere at 1100.degree. to 1500.degree. C. Between 0.1 and 10 mol % of at least one of the ammonium halogenides is added per mol of the Al present to the product thus obtained, and the mixture thus obtained is subsequently subjected to a second heat treatment at a temperature of 700.degree. to 1200.degree. C.
REFERENCES:
patent: 4590405 (1986-05-01), Hoeks et al.
Stevels et al "J. Electrochem Soc.", vol. 123, No. 5, 1976, pp. 691-697.
Duisters Josephus P. H. M.
Pet Robert J.
van den Nieuwenhof Martin M. C. I.
Cooper Jack
Fox John C.
U.S. Philips Corporation
LandOfFree
Method of preparing a luminescent Eu.sup.2 + activated strontium does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of preparing a luminescent Eu.sup.2 + activated strontium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of preparing a luminescent Eu.sup.2 + activated strontium will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2167154