US3761387A
Expired / Lapsed
US
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Process for producing an electrode pitch which can be easily graphitized
Assignee: Rain Carbon Germany GmbH
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Filing: 1971-11-17
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Granted: 1973-09-25
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Expires: 1991-11-17
Abstract
Abstract DISSOLVING A COAL TAR PITCH IN AN AROMATIC RICH OIL FRACTION CONTAINING NAPHTHALENE AND ITS HOMOLOGS AS ITS MAIN INGREDIENTS AND HAVING A BOILING RNAGE OF 200 TO 300*C., IN A WEIGHT RATIO PITCH TO OIL FRACTION OF 1:1 TO 1:4 TO. PRODUCE A SUSPENSION; SEPARATING THE SOLID CONTENT FROM THE SUSPENSION; DISTILLING OFF SAID OIL FRACTION FROM THE FILTRATE AT SUCH A SUMP TEMPERATURE AND WITH SUCH TIME OF STAY FOR THE PITCH FORMING THE SUMP PRODUCT OF THE DISTILLATION COLUMN THAT THE CONTENT OF B-RESINS IS INCREASED WITHOUT FORMING OF ADDITIONAL A-RESINS.
Inventors
- 👤 O Wegener
- 👤 H Louis
- 👤 R Oberkobusch
- 👤 G Collin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:26
CPC Classifications
C; C10; C10C; C10C1/00; C10C1/005; C04; C04B; C04B35/00; C04B35/515; C04B35/52; C04B35/528; C04B35/532
Claims Analysis
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References Cited (Backward Citations)
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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) | 1976-09-24 | 1977-03-26 | 1977-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-24 | 1981-03-26 | 1981-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-24 | 1985-03-26 | 1985-09-25 | $7700.00 | Window Closed / Lapsed |