Patent US4379133A successfully refreshed from Google Patents.
US4379133A
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Process for anisotropic carbon production
Assignee: Rain Carbon Germany GmbH
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Filing: 1981-06-19
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Granted: 1983-04-05
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Expires: 2001-06-19
Abstract
Abstract An improved process for treating coal tar pitch to form anisotropic carbon comprising treating coal tar pitch with picric acid, recovering the resulting picrates, decomposing the picrates and heating the resulting aromatic hydrocarbons to obtain anisotropic carbon in less time.
Inventors
- 👤 Maximilian Zander
- 👤 Gerd-Peter Blumer
- 👤 Gerd Collin
- 👤 Herbert Glaser
- 👤 Rolf Marrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 13:30
CPC Classifications
C; C10; C10B; C10B55/00; C10C; C10C1/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
79 words
A process for the preparation of anistropic carbon comprising extracting coal tar pitch with an organic solvent, adding picric acid to the extract solution to form picrates, recovering the picrates, decomposing the picrates and heating the resulting coal tar pitch fraction at 350° to 550° C. at a pressure of 0.1 to 50 bar for about 100 to 30 minutes to transform it substantially quantitatively into anisotropic carbon and recovering the anisotropic carbon formed at 350° to 550° C.
Claim 2
Dependent Claim
79 words
A process for the preparation of anistropic carbon comprising extracting coal tar pitch with an organic solvent, adding picric acid to the extract solution to form picrates, recovering the picrates, decomposing the picrates and heating the resulting coal tar pitch fraction at 350° to 550° C. at a pressure of 0.1 to 50 bar for about 100 to 30 minutes to transform it substantially quantitatively into anisotropic carbon and recovering the anisotropic carbon formed at 350° to 550° C.
Claim 3
Dependent Claim
17 words
The process of claim 1 wherein the recovered picrates are decomposed by treatment with an aqueous base.
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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) | 1986-04-04 | 1986-10-04 | 1987-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-04 | 1990-10-04 | 1991-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-04 | 1994-10-04 | 1995-04-05 | $7700.00 | Window Closed / Lapsed |