Patent US3167721A successfully refreshed from Google Patents.
US2241321A
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Preparation of polyamides
Assignee: IG Farbenindustrie AG
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Filing: 1938-07-20
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Granted: 1941-05-06
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Expires: 1958-07-20
Abstract
No abstract record available.
Inventors
- 👤 Paul Schlack
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 03:47
CPC Classifications
F; F01; F01P; F01P11/00; F01P11/02; F01P11/0204; F01P11/0209; F01P11/0214; C; C07; C07K; C07K1/00; C07K1/02; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/14; C08G69/16; D; D01; D01F; D01F6/00; D01F6/58; D01F6/60; Y; Y10; Y10S; Y10S264/00; Y10S264/56
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) | 1944-05-05 | 1944-11-04 | 1945-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-05-05 | 1948-11-04 | 1949-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-05-05 | 1952-11-04 | 1953-05-06 | $7700.00 | Window Closed / Lapsed |