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Patent US2578428A successfully refreshed from Google Patents.
US2578428A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of producing copolymers by reacting an n-carboxyl anhydride of an alpha amino acid with an omega amino acid
Assignee: Individual
•
Filing: 1948-04-17
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Granted: 1951-12-11
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Expires: 1968-04-17
Abstract
No abstract record available.
Inventors
- 👤 Kaczalski Efraim
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:43
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
11 words
THE PROCESS WHICH COMPRISES MIXING AN N-CARBOXYL ANHYDRIDE HAVING THE FORMULA
Claim 2
Dependent Claim
11 words
THE PROCESS WHICH COMPRISES MIXING AN N-CARBOXYL ANHYDRIDE HAVING THE FORMULA
References Cited (Backward Citations)
US2071253A
Cited
US2356516A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-12-10 | 1955-06-11 | 1955-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-12-10 | 1959-06-11 | 1959-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-12-10 | 1963-06-11 | 1963-12-11 | $7700.00 | Window Closed / Lapsed |