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US2731445A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyurethanes from piperazines
Assignee: EIDP Inc
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Filing: 1953-03-30
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Granted: 1956-01-17
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Expires: 1973-03-30
Abstract
No abstract record available.
Inventors
- 👤 Emerson L Wittbecker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:43
CPC Classifications
C; C08; C08L; C08L75/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
42 words
A HIGH MELTING PIPERAZINE POLYURETHANE WHICH IS A 1,4-PIPERAZINEDICARBOXYLATE POLYESTER OF A DIHYDROXY AROMATIC HYDROCARBON OF 6 TO 16 CARBON ATOMS WHEREIN THE SHORTEST CHAIN OF CARBON ATOMS CONNECTING THE TWO HYDROXY RADICALS INCLUDES AT LEAST THREE CARBON ATOMS OF ONE RING.
Claim 2
Dependent Claim
42 words
A HIGH MELTING PIPERAZINE POLYURETHANE WHICH IS A 1,4-PIPERAZINEDICARBOXYLATE POLYESTER OF A DIHYDROXY AROMATIC HYDROCARBON OF 6 TO 16 CARBON ATOMS WHEREIN THE SHORTEST CHAIN OF CARBON ATOMS CONNECTING THE TWO HYDROXY RADICALS INCLUDES AT LEAST THREE CARBON ATOMS OF ONE RING.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-01-16 | 1959-07-18 | 1960-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-01-16 | 1963-07-18 | 1964-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-01-16 | 1967-07-18 | 1968-01-17 | $7700.00 | Window Closed / Lapsed |