Patent US3573261A successfully refreshed from Google Patents.
US3573261A
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Polyacylamidrazone carboxylic acid polymers and their procuction
Assignee: Glanzstoff AG
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Filing: 1969-07-22
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Granted: 1971-03-30
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Expires: 1989-07-22
Abstract
Abstract POLYACYLAMIDRAZONE POLYMERS WHICH CONTAIN CARBOXYLIC ACID GROUPS AND WHICH ARE SOLUBLE IN STRONGLY POLAR ORGANIC SOLVENTS, SAID POLYMERS BEING PRODUCED BY REACTING PYROMELLITIC ACID ANHYDRIDE WITH AN BISAMIDRAZONE, E.G. OXAMIDRAZONE, IN APPROXIMATELY EQUIMOLAR PROPORTIONS AND IN A STRONGLY POLAR ORGANIC SOLVENT AT ABOUT 0-70*C., PREFERABLY 15-50*C. THE POLYMERS ARE ESPECIALLY USEFUL AS FILMS, COATINGS AND THE LIKE.
Inventors
- 👤 Hilde Kersten
- 👤 Gerhard Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:41
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067
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) | 1974-03-29 | 1974-09-28 | 1975-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-03-29 | 1978-09-28 | 1979-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-03-29 | 1982-09-28 | 1983-03-30 | $7700.00 | Window Closed / Lapsed |