US2642377A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dewaxing process
Assignee: Shell Development Co
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Filing: 1947-10-27
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Granted: 1953-06-16
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Expires: 1967-10-27
Abstract
No abstract record available.
Inventors
- 👤 Lloyd C Fetterly
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 16:32
CPC Classifications
C; C10; C10G; C10G73/00; C10G73/02; C10G73/24
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
60 words
THE PROCESS FOR DEWAXING LUBRICATING OILS WHICH COMPRISES CONTACTING UREA WITH A PETROLEUM OIL FRACTION CONTAINING MINOR AMOUNTS OF BOTH MICROCRYSTALLINE AND NORMAL PARAFFINE WAXES, AT A TEMPERATURE BETWEEN 25 AND 60* C., WHEREBY CRYSTALLINE MOLECULAR COMPLEXES ARE FORMED BETWEEN UREA AND SUBSTANTIALLY ALL THE WAXY COMPONENTS PRESENT IN SAID OIL, AND SEPARATING SAID COMPLEXES FROM THE DEWAXED LUBRICATING OIL.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-15 | 1956-12-15 | 1957-06-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-15 | 1960-12-15 | 1961-06-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-15 | 1964-12-15 | 1965-06-16 | $7700.00 | Window Closed / Lapsed |