Patent US3669562A successfully refreshed from Google Patents.
Patent US2987406A successfully refreshed from Google Patents.
US2987406A
Expired / Lapsed
US
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High density fly ash fraction
Assignee: CONVERSION SYSTEMS OF PENNSYLVANIA Inc
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Filing: 1958-03-27
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Granted: 1961-06-06
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Expires: 1978-03-27
Abstract
No abstract record available.
Inventors
- 👤 Minnick Leonard John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:28
CPC Classifications
C; C04; C04B; C04B18/00; C04B18/04; C04B18/06; C04B18/08; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/91; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2991
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
97 words
A MATERIAL CONSISTING ESSENTIALLY OF DISCRETE, SUBSTANTIALLY SPHERE-LIKE PARTICLES HAVING A PARTICLE SIZE LESS THAN ABOUT 100 MESH AND CONSISTING ESSENTIALLY OF A SILICAALUMINA GLASS ENVELOPE AND MATRIX, SAID MATRIX HAVING DISPERSED THEREIN CRYSTALLITES OF A FERROMAGNETIC SPINEL, SAID PARTICLES CONTAINING BETWEEN ABOUT 70% AND ABOUT 95% OF IRON, EXPRESSED AS FE2O3, PRESENT AS A CONSTITUENT OF SAID GLASS MATRIX AND OF SAID FERROMAGNETIC SPINEL CRYSTALLITE, BETWEEN ABOUT 3 AND ABOUT 12% OF SILICA AND BETWEEN ABOUT 1 AND ABOUT 6% OF ALUMINA, AND SAID PARTICLES HAVING A SPECIFIC GRAVITY OF FROM ABOUT 3.8 TO ABOUT 4.8.
Claim 2
Dependent Claim
97 words
A MATERIAL CONSISTING ESSENTIALLY OF DISCRETE, SUBSTANTIALLY SPHERE-LIKE PARTICLES HAVING A PARTICLE SIZE LESS THAN ABOUT 100 MESH AND CONSISTING ESSENTIALLY OF A SILICAALUMINA GLASS ENVELOPE AND MATRIX, SAID MATRIX HAVING DISPERSED THEREIN CRYSTALLITES OF A FERROMAGNETIC SPINEL, SAID PARTICLES CONTAINING BETWEEN ABOUT 70% AND ABOUT 95% OF IRON, EXPRESSED AS FE2O3, PRESENT AS A CONSTITUENT OF SAID GLASS MATRIX AND OF SAID FERROMAGNETIC SPINEL CRYSTALLITE, BETWEEN ABOUT 3 AND ABOUT 12% OF SILICA AND BETWEEN ABOUT 1 AND ABOUT 6% OF ALUMINA, AND SAID PARTICLES HAVING A SPECIFIC GRAVITY OF FROM ABOUT 3.8 TO ABOUT 4.8.
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) | 1964-06-05 | 1964-12-05 | 1965-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-06-05 | 1968-12-05 | 1969-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-06-05 | 1972-12-05 | 1973-06-06 | $7700.00 | Window Closed / Lapsed |