US4818434A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermoluminescent material including fusible salt
Assignee: GIMMEL GERALD K PERSONAL REPRESENTATIVE OF ESTATE OF JOSEPH LINDMAYER
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Filing: 1988-04-06
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Granted: 1989-04-04
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Expires: 2008-04-06
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 O.
Inventors
- 👤 Joseph Lindmayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:22
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: 12
Claim 1
Independent Claim
102 words
A crystalline thermoluminescent material consisting essentially of: (a) a base material selected from the group of: alkaline earth metal sulfides, and selenides; (b) a fusible salt, there being at most 2 parts fusible salt for every 10 parts of base material by weight; (c) a first dopant consisting of lanthanum oxide in an amount of between 1,000 and 7,000 parts per million; and (d) 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 than 0.150 eV and more than 0.020 eV.
Claim 2
Dependent Claim
102 words
A crystalline thermoluminescent material consisting essentially of: (a) a base material selected from the group of: alkaline earth metal sulfides, and selenides; (b) a fusible salt, there being at most 2 parts fusible salt for every 10 parts of base material by weight; (c) a first dopant consisting of lanthanum oxide in an amount of between 1,000 and 7,000 parts per million; and (d) 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 than 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
31 words
The thermoluminescent material of claim 1 wherein said fusible salt is lithium fluoride and there is between 1 and 3 parts fusible salt for 64 parts of base material by weight.
Claim 7
Dependent Claim
15 words
A paint having the thermoluminescent material of claim 5 in combination with a liquid vehicle.
Claim 8
Dependent Claim
18 words
The material of claim 1 wherein said thermoluminescent material is in the form of powder having crystalline granules.
Claim 9
Dependent Claim
15 words
A paint having the thermoluminescent material of claim 7 in combination with a liquid vehicle.
Claim 10
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.
Claim 11
Dependent Claim
14 words
A paint having the material of claim 9 in combination with a liquid vehicle.
Claim 12
Dependent Claim
14 words
A paint having the material of claim 1 in combination with a liquid vehicle.
References Cited (Backward Citations)
GB492735A
Cited
US2527365A
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US2521124A
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US2979467A
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JPS57202373A
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US4374037A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-04-03 | 1992-10-03 | 1993-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-04-03 | 1996-10-03 | 1997-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-04-03 | 2000-10-03 | 2001-04-04 | $7700.00 | Window Closed / Lapsed |