Patent US3770147A successfully refreshed from Google Patents.
Patent US3640909A successfully refreshed from Google Patents.
US3640909A
Expired / Lapsed
US
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Substituted acylated polyimine resins
Assignee: Dow Chemical Co
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Filing: 1969-02-17
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Granted: 1972-02-08
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Expires: 1989-02-17
Abstract
Abstract HIGH MOLECULAR WEIGHT BRANCED POLYIMINE RESINS USEFUL IN PAPER MANUFACTURE ARE MADE BY PARTIALLY DEACYLATING A LINEAR N-ACYLATED ETHYLENIMINE POLYMER BY ACID HYDROLYSIS AND REACTING THE PRODUCT WITH A POLYFUNCTIONAL CROSSLINKING AGENT SUCH AS AN EPIHALOHYDRIN OR A DIEPOXIDE. PREFERABLY, THE ACYLATED POLYMER IS PRODUCED BY POLYMERIZING A 2-SUBSTITUTED OXAZOLINE IN THE PRESENCE OF A CATIONIC CATALYST.
Inventors
- 👤 Giffin D Jones
- 👤 Harold H Roth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:50
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/02; C08G73/0233; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/64; C08G18/6415; C08G18/6423
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) | 1975-02-07 | 1975-08-09 | 1976-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-07 | 1979-08-09 | 1980-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-07 | 1983-08-09 | 1984-02-08 | $7700.00 | Window Closed / Lapsed |