Patent US2928788A successfully refreshed from Google Patents.
US2928788A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Viscosity index and oxidation stability of lubricating oil
Assignee: Sunoco Inc
•
Filing: 1957-05-08
•
Granted: 1960-03-15
•
Expires: 1977-05-08
Abstract
No abstract record available.
Inventors
- 👤 James L Jezl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:38
CPC Classifications
C; C10; C10G; C10G21/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
76 words
METHOD FOR PERPARING LUBRICATING OILS HAVING HIGH VISCOSITY INDEX AND GOOD OXIDATION STABILITY WHICH COMPRISES EXTRACTING MONONUCLEAR AND POLYNUCLEAR AROMATIC HYDROCARBON FROM A PETROLEUM LUBRICATING OIL CHARGE STOCK: CONTACTING THE RESULTING LUBRICATING OIL, FROM WHICH MONONUCLEAR AND POLYNUCLEAR AROMATIC HYDROCARBON HAVE BEEN EXTRACTEDM WITH A SELECTIVE SOLVENT FOR AROMATIC HYDROCARBONS, SAID SOLVENT CONTAINING AROMATIC HYDROCARBONS MORE CONCENTRATED IN POLYNUCLEAR AROMATIC HYDROCARBONS THAN THE TOTAL HYDROCARBONS PREVIOUSLY EXTRACTED FROM THE OIL, AND SEPARATING SOLVENT FROM LUBRICATING OIL
Claim 2
Dependent Claim
76 words
METHOD FOR PERPARING LUBRICATING OILS HAVING HIGH VISCOSITY INDEX AND GOOD OXIDATION STABILITY WHICH COMPRISES EXTRACTING MONONUCLEAR AND POLYNUCLEAR AROMATIC HYDROCARBON FROM A PETROLEUM LUBRICATING OIL CHARGE STOCK: CONTACTING THE RESULTING LUBRICATING OIL, FROM WHICH MONONUCLEAR AND POLYNUCLEAR AROMATIC HYDROCARBON HAVE BEEN EXTRACTEDM WITH A SELECTIVE SOLVENT FOR AROMATIC HYDROCARBONS, SAID SOLVENT CONTAINING AROMATIC HYDROCARBONS MORE CONCENTRATED IN POLYNUCLEAR AROMATIC HYDROCARBONS THAN THE TOTAL HYDROCARBONS PREVIOUSLY EXTRACTED FROM THE OIL, AND SEPARATING SOLVENT FROM 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) | 1963-03-15 | 1963-09-14 | 1964-03-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-03-15 | 1967-09-14 | 1968-03-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-03-15 | 1971-09-14 | 1972-03-15 | $7700.00 | Window Closed / Lapsed |