Patent US2540855A successfully refreshed from Google Patents.
US2540855A
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Formic acid solutions of synthetic linear polyamides from alphamino acids
Assignee: EIDP Inc
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Filing: 1949-02-02
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Granted: 1951-02-06
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Expires: 1969-02-02
Abstract
No abstract record available.
Inventors
- 👤 Tullock Charles William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:07
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C08J3/091; C08J3/095; C08J2377/00; C08J2377/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
A SOLUTION IN FORMIC ACID OF AN OPTICALLY INACTIVE CONDENSATION POLYMER WHEREIN THE POLYMER CHAIN CONSISTS OF ALPHA-PRIMARY MONOAMINOMONOCARBOXYLIC ACID UNITS OF WHICH AT LEAST 20% ARE OF THE FORMULA-NH-CHR-CO-WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF METHYL, ETHYL, ISOPROPYL, AND SECONDARY BUTYL RADICALS.
Claim 2
Dependent Claim
45 words
A SOLUTION IN FORMIC ACID OF AN OPTICALLY INACTIVE CONDENSATION POLYMER WHEREIN THE POLYMER CHAIN CONSISTS OF ALPHA-PRIMARY MONOAMINOMONOCARBOXYLIC ACID UNITS OF WHICH AT LEAST 20% ARE OF THE FORMULA-NH-CHR-CO-WHEREIN R IS SELECTED FROM THE GROUP CONSISTING OF METHYL, ETHYL, ISOPROPYL, AND SECONDARY BUTYL RADICALS.
References Cited (Backward Citations)
US2130948A
Cited
US2293761A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-02-05 | 1954-08-07 | 1955-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-02-05 | 1958-08-07 | 1959-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-02-05 | 1962-08-07 | 1963-02-06 | $7700.00 | Window Closed / Lapsed |