US3897456A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sludge inhibitor for hydrocarbon oils
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1973-02-16
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Granted: 1975-07-29
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Expires: 1993-02-16
Abstract
Abstract A tetrahydric alcohol derived from urea or thiourea and an alkanol amine is esterified with a long chain monocarboxylic acid or dicarboxylic acid, producing an additive that is very effective in reducing the sludging tendencies of hydrocarbon oils. The additive is particularly useful for stabilizing hydrotreated lubricants and fuel stocks against the deposition of sludge when exposed to sunlight.
Inventors
- 👤 Phillip W Brewster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:01
CPC Classifications
C; C10; C10M; C10M135/00; C10M135/12; C10M135/14; C10M135/16; C08; C08F; C08F8/00; C08F8/14; C10L; C10L1/00; C10L1/10; C10L1/14; C10L1/22; C10L1/234; C10L1/238; C10L1/24; C10L1/2462; C10L1/2475; C10M133/00; C10M133/52; C10M133/54; C08F2810/00; C08F2810/30; C10M2215/00; C10M2215/10; C10M2215/102; C10M2219/00; C10M2219/06; C10M2219/062; C10M2219/064; C10N; C10N2030/00; C10N2030/12; C10N2070/00; C10N2070/02
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
67 words
THE OIL-SOLUBLE ESTER OBTAINED BY THE ESTERIFICATION OF ABOUT EQUAL MOLAR PROPORTIONS OF (A) A POLYISOBUTENYL SUCCINIC ACID OR ACID ANHYDRIDE WHEREIN SAID POLISOBUTENYL GROUP CONTAINS BETWEEN 40 AND 250 CARBON ATOMS WITH (B) A TETREHYDROXYALKYL-SUBSTITUTED UREA WHICH IS THE CONDENSATION PRODUCT OF 1 MOLAR PROPORTION OF UREA WITH ABOUT 2 MOLAR PROPORTIONS OF A DIALKANOLAMINE HAVING FROM 1 TO 6 CAARBON ATOMS IN EACH ALKANOL GROUP.
Claim 2
Dependent Claim
67 words
THE OIL-SOLUBLE ESTER OBTAINED BY THE ESTERIFICATION OF ABOUT EQUAL MOLAR PROPORTIONS OF (A) A POLYISOBUTENYL SUCCINIC ACID OR ACID ANHYDRIDE WHEREIN SAID POLISOBUTENYL GROUP CONTAINS BETWEEN 40 AND 250 CARBON ATOMS WITH (B) A TETREHYDROXYALKYL-SUBSTITUTED UREA WHICH IS THE CONDENSATION PRODUCT OF 1 MOLAR PROPORTION OF UREA WITH ABOUT 2 MOLAR PROPORTIONS OF A DIALKANOLAMINE HAVING FROM 1 TO 6 CAARBON ATOMS IN EACH ALKANOL GROUP.
Claim 3
Dependent Claim
20 words
The ester of claim 1 wherein said polyisobutenyl group is derived from a polyisobutylene of 800 to 2100 molecular weight.
References Cited (Backward Citations)
US3340190A
Cited
US3324033A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-07-28 | 1979-01-27 | 1979-07-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-07-28 | 1983-01-27 | 1983-07-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-07-28 | 1987-01-27 | 1987-07-29 | $7700.00 | Window Closed / Lapsed |