US2618567A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Molded alumina
Assignee: Saint Gobain Abrasives Inc
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Filing: 1950-10-19
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Granted: 1952-11-18
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Expires: 1970-10-19
Abstract
No abstract record available.
Inventors
- 👤 George E Comstock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:47
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/622; C04B35/64; C04B35/645
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
AN ARTICLE OF MANUFACTURE HAVING A COMPOSITION CONSISTING OF FROM 0.2% TO 1.0% OF MAGNESIA, FROM 0.7% TO 1.0% OF COBALT OXIDE AND AT LEAST 99% OF THE REMAINDER BEING ALUMINA AL2O3, THE ARTICLE BEING OF FINE CRYSTALLINE STRUCTURE DEVELOPED BY HOT PRESSURE MOLDING AT A TEMPERATURE OF AT LEAST 1650* C. AND NOT HIGHER THAN 1800* C. AND A PRESSURE OF AT LEAST 500 POUNDS PER SQUARE INCH, AND HAVING A SPECIFIC GRAVITY OF AT LEAST 3.94 AND A STRENGTH IN COMPRESSION GREATER THAN 450,000 POUNDS PER SQUARE INCH.
Claim 2
Dependent Claim
90 words
AN ARTICLE OF MANUFACTURE HAVING A COMPOSITION CONSISTING OF FROM 0.2% TO 1.0% OF MAGNESIA, FROM 0.7% TO 1.0% OF COBALT OXIDE AND AT LEAST 99% OF THE REMAINDER BEING ALUMINA AL2O3, THE ARTICLE BEING OF FINE CRYSTALLINE STRUCTURE DEVELOPED BY HOT PRESSURE MOLDING AT A TEMPERATURE OF AT LEAST 1650* C. AND NOT HIGHER THAN 1800* C. AND A PRESSURE OF AT LEAST 500 POUNDS PER SQUARE INCH, AND HAVING A SPECIFIC GRAVITY OF AT LEAST 3.94 AND A STRENGTH IN COMPRESSION GREATER THAN 450,000 POUNDS PER SQUARE INCH.
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) | 1955-11-18 | 1956-05-19 | 1956-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-11-18 | 1960-05-19 | 1960-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-11-18 | 1964-05-19 | 1964-11-18 | $7700.00 | Window Closed / Lapsed |