Patent US3147225A successfully refreshed from Google Patents.
US3147225A
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Radioactive sources and method for making
Assignee: 3M Co
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Filing: 1958-01-30
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Granted: 1964-09-01
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Expires: 1978-01-30
Abstract
No abstract record available.
Inventors
- 👤 John P Ryan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:40
CPC Classifications
G; G21; G21G; G21G4/00; G21G4/04; G21G4/06; C; C03; C03C; C03C10/00; C03C3/00; C03C3/12; C03C3/16; C03C3/21
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
105 words
AS A NEW ARTICLE SOURCE OF RADIOACTIVITY: A PARTICLE HAVING A THICKNESS NO GREATER THAN 2 MM. AND CONSISTING ESENTIALLY OF A WEATHER-RESISTANT REFRACTORY MATRIX AT LEAST PARTIALLY DEVITRIFIED AND CHARACTERIZED BY REMAINING AS A DESCRETE ENTITY NOT BONDED TO A LIKE PARTICLE OF IDENTICAL MATRIX EVEN WHEN SUBJECTED TO 1000*C. IN CONTACT WITH SAID LIKE PARTICLE, AND A RADIOACTIVE ISOTOPE DISPERSED IN SAID MATRIX BY ION EXCHANGE AND STRUCTURALLY BONDED WITHIN SHRUNKEN PORES OF SAID MATRIX, SAID PARTICLE BEING CHARACTERIZED BY AN ABILITY TO WITHSTAND WATER EXPOSURE FOR ONE WEEK AT 50*C. WITH LESS THAN 0.1% WEIGHT LOSS OF SAID STRUCTRUALLY BONDED RADIOACTIVE ISOTOPE.
Claim 2
Dependent Claim
105 words
AS A NEW ARTICLE SOURCE OF RADIOACTIVITY: A PARTICLE HAVING A THICKNESS NO GREATER THAN 2 MM. AND CONSISTING ESENTIALLY OF A WEATHER-RESISTANT REFRACTORY MATRIX AT LEAST PARTIALLY DEVITRIFIED AND CHARACTERIZED BY REMAINING AS A DESCRETE ENTITY NOT BONDED TO A LIKE PARTICLE OF IDENTICAL MATRIX EVEN WHEN SUBJECTED TO 1000*C. IN CONTACT WITH SAID LIKE PARTICLE, AND A RADIOACTIVE ISOTOPE DISPERSED IN SAID MATRIX BY ION EXCHANGE AND STRUCTURALLY BONDED WITHIN SHRUNKEN PORES OF SAID MATRIX, SAID PARTICLE BEING CHARACTERIZED BY AN ABILITY TO WITHSTAND WATER EXPOSURE FOR ONE WEEK AT 50*C. WITH LESS THAN 0.1% WEIGHT LOSS OF SAID STRUCTRUALLY BONDED RADIOACTIVE ISOTOPE.
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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) | 1967-09-01 | 1968-03-02 | 1968-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-09-01 | 1972-03-02 | 1972-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-09-01 | 1976-03-02 | 1976-09-01 | $7700.00 | Window Closed / Lapsed |