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US5230831A
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Europium- and bismuth-doped luminescent compositions
Assignee: General Electric Co
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Filing: 1992-11-06
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Granted: 1993-07-27
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Expires: 2012-11-06
Abstract
Abstract Phosphorescent compositions of the formula NaY 1-x A x M 2 O 6 , wherein A is europium or bismuth, M is zirconium or hafnium and x is in the range of about 0.001-0.25, are prepared by the reaction of appropriate proportions of sodium bicarbonate and the corresponding metal oxides. They have a cubic fluorite-type crystal lattice.
Inventors
- 👤 Alok M. Srivastava
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 14:43
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7783; C09K11/7784; C09K11/7787; C09K11/7701
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
44 words
A luminescent crystalline composition having the formula NaY 1-x A x M 2 O 6 , wherein A is europium or bismuth, M is zirconium or hafnium and x is in the range of about 0.001-0.25, said composition having a cubic fluorite-type crystal lattice.
Claim 2
Dependent Claim
44 words
A luminescent crystalline composition having the formula NaY 1-x A x M 2 O 6 , wherein A is europium or bismuth, M is zirconium or hafnium and x is in the range of about 0.001-0.25, said composition having a cubic fluorite-type crystal lattice.
Claim 3
Dependent Claim
10 words
A composition according to claim 1 wherein M is zirconium.
Claim 4
Dependent Claim
10 words
A composition according to claim 2 wherein A is europium.
Claim 5
Dependent Claim
10 words
A composition according to claim 3 wherein x is 0.005.
Claim 6
Dependent Claim
10 words
A composition according to claim 3 wherein x is 0.05.
Claim 7
Dependent Claim
10 words
A composition according to claim 3 wherein x is 0.1.
Claim 8
Dependent Claim
10 words
A composition according to claim 3 wherein x is 0.2.
Claim 9
Dependent Claim
10 words
A composition according to claim 2 wherein A is bismuth.
Claim 10
Dependent Claim
10 words
A composition according to claim 8 wherein x is 0.05.
Claim 11
Dependent Claim
10 words
A composition according to claim 1 wherein M is hafnium.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-07-26 | 1997-01-25 | 1997-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-26 | 2001-01-25 | 2001-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-26 | 2005-01-25 | 2005-07-27 | $7700.00 | Window Closed / Lapsed |