US4728459A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tungsten-containing zinc silicate phosphor
Assignee: Osram Sylvania Inc
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Filing: 1984-10-24
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Granted: 1988-03-01
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Expires: 2004-10-24
Abstract
Abstract A manganese-activated zinc silicate phosphor contains a small amount of tungsten dispersed throughout the phosphor matrix. The tungsten improves maintenance of a fluorescent lamp in which the phosphor is used.
Inventors
- 👤 Albert K. Fan
- 👤 Vincent Chiola
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:00
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/02; C09K11/025; C09K11/08; C09K11/67; C09K11/68; C09K11/685
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
12 words
A manganese-activated zinc silicate phosphor containing tungsten dispersed throughout the phosphor matrix.
Claim 2
Dependent Claim
12 words
A manganese-activated zinc silicate phosphor containing tungsten dispersed throughout the phosphor matrix.
Claim 3
Dependent Claim
17 words
The phosphor of claim 1 wherein the amount of tungsten is about 0.05 to 0.3 mole percent.
Claim 4
Dependent Claim
32 words
A manganese-activated zinc silicate phosphor containing tungsten dispersed throughout the phosphor matrix, the amount of tungsten being sufficient to improve lamp maintenance of a fluorescent lamp in which the phosphor is used.
Claim 5
Dependent Claim
32 words
A manganese-activated zinc silicate phosphor containing tungsten dispersed throughout the phosphor matrix, the amount of tungsten being sufficient to improve lamp maintenance of a fluorescent lamp in which the phosphor is used.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-01 | 1991-08-31 | 1992-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-01 | 1995-08-31 | 1996-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-01 | 1999-08-31 | 2000-03-01 | $7700.00 | Window Closed / Lapsed |