Patent US3558573A successfully refreshed from Google Patents.
US3558573A
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Novel polyesters from hydrazines and lactones and a process for their production
Assignee: Bayer AG
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Filing: 1969-04-21
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Granted: 1971-01-26
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Expires: 1989-04-21
Abstract
Abstract HYDROXYL POLYESTERS HAVING A MOLECULAR WEIGHT OF FROM ABOUT 300 TO ABOUT 20,000 ARE PREPARED BY POLYMERIZING A LACTONE HAVING FROM 7 TO 9 MEMBERS IN T HE RING IN THE PRESENCE OF A HYDRAZINE. THE POLYESTERS ARE SUITABLE FOR PLASTICIZERS AND STABILIZERS FOR POLYVINYL CHLORIDE OR AS A REACTANT WITH POLYISOCYANATE TO PREPARE POLYURETHANES.
Inventors
- 👤 Wolf-Dieter Wirth
- 👤 Erwin Muller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:47
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/68; C08G63/685; C08G63/6852
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) | 1974-01-25 | 1974-07-27 | 1975-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-25 | 1978-07-27 | 1979-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-25 | 1982-07-27 | 1983-01-26 | $7700.00 | Window Closed / Lapsed |