Patent US2640848A successfully refreshed from Google Patents.
US2640848A
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Esters of sulfur-containing polycarboxylic acids
Assignee: Shell Development Co
•
Filing: 1949-10-15
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Granted: 1953-06-02
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Expires: 1969-10-15
Abstract
No abstract record available.
Inventors
- 👤 Harman Denham
- 👤 De Loss E Winkler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:04
CPC Classifications
C; C07; C07C; C07C317/00; C07C317/44; C08; C08K; C08K5/00; C08K5/36; C08K5/41
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
2 words
DI(2-ETHYLHEXYL) BETA,BETA''-SULFONYLDIBUTYRATE.
Claim 2
Dependent Claim
2 words
DI(2-ETHYLHEXYL) BETA,BETA''-SULFONYLDIBUTYRATE.
References Cited (Backward Citations)
US2028091A
Cited
US2176423A
Cited
US2473708A
Cited
US2427640A
Cited
US2474350A
Cited
US2596438A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-01 | 1956-12-01 | 1957-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-01 | 1960-12-01 | 1961-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-01 | 1964-12-01 | 1965-06-02 | $7700.00 | Window Closed / Lapsed |