US3679644A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyalkylmethacrylates as pour point depressants for lubricating oils
Assignee: Shell USA Inc
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Filing: 1970-07-15
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Granted: 1972-07-25
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Expires: 1990-07-15
Abstract
Abstract POUR POINTS OF LUBRICATING OILS WITH WIDELY VARYING VISCOSITIES ARE DEPRESSED BY ADDING THERETO SMALL AMOUNTS OF NOVEL OIL SOLUBLE POLYALKYLMETHACRYLATES.
Inventors
- 👤 Pieter H Van Der Meij
- 👤 Arnold A Buitelaar
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:22
CPC Classifications
C; C10; C10M; C10M145/00; C10M145/02; C10M145/10; C10M145/12; C10M145/14; C08; C08F; C08F220/00; C08F220/02; C08F220/10; C08F220/12; C08F220/16; C08F220/18; C08F220/1812; C10M2203/00; C10M2203/10; C10M2203/108; C10M2209/00; C10M2209/02; C10M2209/08; C10M2209/084; C10N; C10N2050/00; C10N2050/015; C10N2050/02; C10N2070/00; C10N2070/02
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) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |