Patent US3147205A successfully refreshed from Google Patents.
US3147205A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Upgrading coal tar
Assignee: Pittsburgh Chemical Co
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Filing: 1961-07-18
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Granted: 1964-09-01
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Expires: 1981-07-18
Abstract
No abstract record available.
Inventors
- 👤 Ernest O Ohsol
- 👤 Graham N Gleysteen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 18:08
CPC Classifications
C; C10; C10C; C10C1/00; C10C1/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
37 words
A PROCESS FOR REMOVAL OF THE INORGANIC COMPONENTS, AND QUINOLINE INSOLUBLE CARBON FROM COAL TAR COMPRISING EXTRACTING THE COAL TAR WITH BENZENE AT A TEMPERATURE BETWEEN 120 AND 200*C. AND SUPERATMOSPHERIC PRESSURE OF 35 TO 300 P.S.I.G.
Claim 2
Dependent Claim
37 words
A PROCESS FOR REMOVAL OF THE INORGANIC COMPONENTS, AND QUINOLINE INSOLUBLE CARBON FROM COAL TAR COMPRISING EXTRACTING THE COAL TAR WITH BENZENE AT A TEMPERATURE BETWEEN 120 AND 200*C. AND SUPERATMOSPHERIC PRESSURE OF 35 TO 300 P.S.I.G.
References Cited (Backward Citations)
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US2871181A
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US2980602A
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US2989458A
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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) | 1967-09-01 | 1968-03-02 | 1968-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-09-01 | 1972-03-02 | 1972-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-09-01 | 1976-03-02 | 1976-09-01 | $7700.00 | Window Closed / Lapsed |