Patent US2502576A successfully refreshed from Google Patents.
US2502576A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of polyamides containing glutarimide rings
Assignee: Celanese Corp
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Filing: 1946-03-06
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Granted: 1950-04-04
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Expires: 1966-03-06
Abstract
No abstract record available.
Inventors
- 👤 Lincoln James
- 👤 Drewitt James Gordon Napier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:39
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
41 words
PROCESS FOR THE PRODUCTION OF LINEAR POLYAMIDES WHICH COMPRISES CONDENSING IN SUBSTANTIALLY EQUIMOLECULAR PROPORTIONS THE DI-FORMYL DERIVATIVE OF A DI-PRIMARY DIAMINE, IN WHICH THE FORMYL-AMINO GROUPS ARE THE SOLE REACTIVE GROUPS, WITH 1.3.5-PENTANE-TRICARBOXYLIC ACID UNTIL A LINEAR FIBER-FORMING POLYMER IS OBTAINED.
Claim 2
Dependent Claim
41 words
PROCESS FOR THE PRODUCTION OF LINEAR POLYAMIDES WHICH COMPRISES CONDENSING IN SUBSTANTIALLY EQUIMOLECULAR PROPORTIONS THE DI-FORMYL DERIVATIVE OF A DI-PRIMARY DIAMINE, IN WHICH THE FORMYL-AMINO GROUPS ARE THE SOLE REACTIVE GROUPS, WITH 1.3.5-PENTANE-TRICARBOXYLIC ACID UNTIL A LINEAR FIBER-FORMING POLYMER IS OBTAINED.
References Cited (Backward Citations)
US2421024A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-04-03 | 1953-10-03 | 1954-04-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-04-03 | 1957-10-03 | 1958-04-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-04-03 | 1961-10-03 | 1962-04-04 | $7700.00 | Window Closed / Lapsed |