Patent US3597391A successfully refreshed from Google Patents.
US3597391A
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Aromatic polyamide imines,novel n-aryl substituted - polybenzimidazoles derived therefrom,and process for preparation thereof
Assignee: Teijin Ltd
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Filing: 1968-09-06
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Granted: 1971-08-03
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Expires: 1988-09-06
Abstract
Abstract A PROCESS FOR PREPARING A POLYAMIDE IMINE AND A HEATSTABLE POLYBENZIMIDAZOLE WHICH COMPRISES REACTING AN AROMATIC TRIAMINE SUCH AS 2,4''-DIAMINODIPHENYLAMINE WHEREIN TWO AMINO GROUPS ARE ATACHED TO ORTHO-POSITIONS OF AN AROMATIC RING, OR AN AROMATIC TETRAMINE SUCH AS N,N''-BIS-(2-AMINOPHENYL-P-PHENYLENEDIAMINE) WHEREIN EACH TWO AMINO GROUPS ARE ATTACHED TO ORTHO POSITIONS OF EACH SEPARATE AROMATIC RING, WITH AN AROMATIC DICARBOXYLIC HALIDE TO FORM A POLYAMIDE IMINE WHICH IS SOLUBLE IN A NORMAL ORGANIC SOLVENT, AND HEATING OR CHEMICALLY TREATING SAID POLYAMIDE IMINE TO CONVERT IT INTO A HEAT STABLE POLYBENZIMIDAZOLE.
Inventors
- 👤 Shigeyoshi Hara
- 👤 Moriya Uchida
- 👤 Masao Senoo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 22:34
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/26; C08G69/32; C08G73/00; C08G73/06; C08G73/18
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) | 1974-08-02 | 1975-02-01 | 1975-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-02 | 1979-02-01 | 1979-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-02 | 1983-02-01 | 1983-08-03 | $7700.00 | Window Closed / Lapsed |