US3660273A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of improved lubricating oils by hydrocracking and solvent extraction
Assignee: Texaco Inc
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Filing: 1969-11-12
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Granted: 1972-05-02
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Expires: 1989-11-12
Abstract
Abstract LUBE OILS OF IMPROVED ULTAVIOLET STABILITY, COLOR AND VISCOSITY INDEX ARE OBTAINED BY HYDROCRACKING A LUBE OIL FRACTION AND SUBJECTING THE PRODUCT TO SOLVENT REFINING THE THEN DEWAXING. THE PREFERRED SOLVENT IS N-METHYL-2PYRROLIDONE. THE FEED MAY BE A WAX DISTILLATE, A DEASPHALTED RESIDUUM AND MAY BE SUBJECTED TO PRE-HYDROCRACKING SOLVENT REFINING STEP.
Inventors
- 👤 Billy H Cummins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:34
CPC Classifications
C; C10; C10G; C10G67/00; C10G67/02; C10G67/04; C10G67/0409; C10G67/0445; C10G2400/00; C10G2400/10
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) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |