US3640957A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Monooxazoline and oxazine cured epoxy resins
Assignee: Dow Chemical Co
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Filing: 1969-06-16
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Granted: 1972-02-08
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Expires: 1989-06-16
Abstract
Abstract -C<(=N-(CH(-R"))M-O-) + OXIRANYL ---> 2,3-(-(CH(-R"))M- O-)-OXAZOLIDIN-2,5-DIYL WHEREIN R" IS HYDROGEN OR LOWERALKYL C1-4, M IS 2 OR 3, AND EACH HETEROCYCLE IS PART OF AN ENTIRE MOLECULE. IT IS A HIGHLY EFFECTIVE CURING AGENT, BY BOTH REACTION AND CATALYSIS, FOR POLYEPOXIDES TO OBTAIN EPOXY RESINS.
Inventors
- 👤 Donald A Tomalia
- 👤 Robert J Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:14
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/50; C08G59/5046
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 |