Patent US3678005A successfully refreshed from Google Patents.
US3678005A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mixed imide-isoindoloquinazolinediones heterocyclic polymers
Assignee: IFP Energies nouvelles
•
Filing: 1970-04-14
•
Granted: 1972-07-18
•
Expires: 1990-04-14
Abstract
Abstract HEAT-RESISTANT, AS WELL AS TOUGH POLYMERS ARE PROVIDED CONSISTING ESSENTIALLY OF RECURRING UNITS OF AT LEAST ONE OF THE FOLLOWING FORMULAE: (CH3-CO)2-N-AR<(-CO-N(-)-CO-R(-CH3)2-C(-)=N-) WHERE N AND C ARE JOINED, AND (CH3-CO)2-N-AR<(-CO-N=C(-)-R(-CH3)2- CO-N(-)-) WHERE N AND C ARE JOINED WHEREIN AR IS SELECTED FROM HOMOCYCLIC AND HETEROCYCLIC TRIVALENT AROMATIC RADICALS, THE THREE VALENCES OF WHICH ARE LINKED TO DIFFERENT CARBON ATOMS, TWO OF SAID VALENCIES BEING LINKED TO ADJACENT CARBON ATOMS, AND R IS A TETRAVALENT ORGANIC RADICAL CONTAINING AT LEAST TWO CARBON ATOMS. PRECURSORS AND PROCESS TO PRODUCE THESE POLYMERS ARE ALSO DESCRIBED.
Inventors
- 👤 Guy Rabilloud
- 👤 Gabriel De Gaudemaris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:21
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1085
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1975-07-18 | 1976-01-17 | 1976-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-18 | 1980-01-17 | 1980-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-18 | 1984-01-17 | 1984-07-18 | $7700.00 | Window Closed / Lapsed |