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US3516973A
Expired / Lapsed
US
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Process for the polymerization of beta-lactones
Assignee: Daicel Corp
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Filing: 1968-03-25
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Granted: 1970-06-23
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Expires: 1988-03-25
Abstract
No abstract record available.
Inventors
- 👤 Rikitaro Kato
- 👤 Syoichi Nagato
- 👤 Juro Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:46
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/78; C08G63/82; C08G63/823
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
GB1016394A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-06-22 | 1973-12-22 | 1974-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-22 | 1977-12-22 | 1978-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-22 | 1981-12-22 | 1982-06-23 | $7700.00 | Window Closed / Lapsed |