Patent US1455682A successfully refreshed from Google Patents.
Patent US3787541A successfully refreshed from Google Patents.
US3787541A
Expired / Lapsed
US
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Graphitization of mesophase pitch fibers
Assignee: Akzo NV
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Filing: 1971-10-26
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Granted: 1974-01-22
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Expires: 1991-10-26
Abstract
Abstract SINGLE PHASE GRAPHITE IS OBTAINED BY EXTRUDING MESOPHASE PREPARING BY HEATING A CARBONACEOUS MATERIAL SUCH AS A HYDROCARBON COKER FEED, COAL TAR PITCH, ETHYLENE TAR PITCH, ECT. AT A TEMPERATURE ABOVE 400*C. UNTIL AT LEAST 75 PERCENT QUINOLINE-INSOLUBLE MESOPHASE HAS BEEN FORMED EXTRUDING THE RESULTANT MATERIAL AT A TEMPERATURE BETWEEN THE SOFTENING POINT OF THE MESOPHASE AND 700*C. AND SUBSEQUENTLY CARBONIZING THE FORMED PRODUCT BY HEATING IT IN A NON-OXIDIZING ATMOSPHERE TO TEMPERATURES FROM ABOUT 1000*C. TO ABOUT 3000*C. HIGH DENSITY MATERIAL CAN THUS BE OBTAINED WITH CONTROLLED ALIGMENT OF THE GRAPHITIC STRUCTURE.
Inventors
- 👤 M Whittaker
- 👤 L Grindstaff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:20
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01F9/145; C; C01; C01B; C01B32/00; Y; Y10; Y10S; Y10S264/00; Y10S264/19
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-21 | 1977-07-23 | 1978-01-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-21 | 1981-07-23 | 1982-01-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-21 | 1985-07-23 | 1986-01-22 | $7700.00 | Window Closed / Lapsed |