US3578633A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for curing polyepoxides with polycarboxylic acid anhydrides in presence of alkaline metal salts of carboxylic acids
Assignee: Shell USA Inc
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Filing: 1968-12-11
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Granted: 1971-05-11
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Expires: 1988-12-11
Abstract
Abstract POLYEPOXIDES MAY BE CURED TO AN INSOLUBLE, INFUSIBLE PRODUCT BY REACTING A POLYEPOXIDE CONTAINING MORE THAN ONE VICINAL EPOXY GROUP PER MOLECULE WITH A POLYCARBOXYLIC ACID ANHYDRIDE IN THE PLRESNECE OF AN ALKALINE METAL SALT OF A CARBOXYLIC ACID.
Inventors
- 👤 Gerd Rossa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 12:13
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/68; C08G59/681; C08G59/685; C08G59/40; C08G59/42; C08G59/4292
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) | 1974-05-10 | 1974-11-09 | 1975-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-10 | 1978-11-09 | 1979-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-10 | 1982-11-09 | 1983-05-11 | $7700.00 | Window Closed / Lapsed |