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US4755324A
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Thermoluminescent material
Assignee: GIMMEL GERALD K PERSONAL REPRESENTATIVE OF ESTATE OF JOSEPH LINDMAYER
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Filing: 1985-11-15
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Granted: 1988-07-05
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Expires: 2005-11-15
Abstract
Abstract Materials having thermoluminescent properties use a base material and two dopants and made from a process of mixing the parts together, heating the mixture to fuse together, grinding the mass into a fine powder, and reheating the powder. The resultant powder may be combined with a vehicle to form a paint. A fusible salt may be used in making the thermoluminescent material. The dopants may be Eu 2 O 3 , Sm, Ce O 2 , and/or La 2 O 3 .
Inventors
- 👤 Joseph Lindmayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:11
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/77; C09K11/7783; C09K11/7784; C09K11/7786; C09K11/7787; C09K11/7789; C09K11/88; C09K11/881; C09K11/885
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
81 words
A crystalline thermoluminescent material consisting essentially of: (a) a base material selected from the group of: alkaline earth metal sufides, and selenides; (b) a first dopant consisting of lanthanum oxide in an amount of between 1000 and 7,000 parts per million; and (c) a second dopant consisting of europium trioxide in an amount of between 500 and 1,000 parts per million; and wherein said thermoluminescent material provides electron trapping with trap depths less that 0.150 eV and more than 0.020 eV.
Claim 2
Dependent Claim
81 words
A crystalline thermoluminescent material consisting essentially of: (a) a base material selected from the group of: alkaline earth metal sufides, and selenides; (b) a first dopant consisting of lanthanum oxide in an amount of between 1000 and 7,000 parts per million; and (c) a second dopant consisting of europium trioxide in an amount of between 500 and 1,000 parts per million; and wherein said thermoluminescent material provides electron trapping with trap depths less that 0.150 eV and more than 0.020 eV.
Claim 3
Dependent Claim
22 words
The thermoluminescent material of claim 1 wherein said thermoluminescent material has 3000 plus or minus 10% parts per million of lanthanum oxide.
Claim 4
Dependent Claim
26 words
The thermoluminescent material of claim 1 wherein said thermoluminescent material has 750 plus or minus 10% parts per million of europium trioxide as the second dopant.
Claim 5
Dependent Claim
13 words
The thermoluminescent material of claim 1 wherein said base material is strontium sulfide.
Claim 6
Dependent Claim
19 words
The thermoluminescent material of claim 1 wherein said thermoluminescent material is in the form of powder having crystalline granules.
Claim 7
Dependent Claim
33 words
The thermoluminescent material of claim 1 wherein said material has 3000 plus or minus 10% parts per million of lanthanum oxide and 750 plus or minus 10% parts per million of europium trioxide.
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) | 1991-07-05 | 1992-01-04 | 1992-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-05 | 1996-01-04 | 1996-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-05 | 2000-01-04 | 2000-07-05 | $7700.00 | Window Closed / Lapsed |