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Patent US3803100A successfully refreshed from Google Patents.
US3803100A
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Method for preparing soluble polyamideimides
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1971-07-12
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Granted: 1974-04-09
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Expires: 1991-07-12
Abstract
Abstract PHENOLIC ACIDIC SOLVENT-SOLUBLE AND INFUSIBLE LINEAR AROMATIC POLYAMIDE-IMIDES OF HIGH MOLECULAR WEIGHT HAVING AMIDE BONDING AND A 5-MEMBERED IMIDE RING IN THE MOLECULE WHICH IS OBTAINED BY SUBJECTING TRICARBOXYLIC ANHYDRIDE AND DIISOCYANATE TO HEATING AND MELT STATE REACTION AT A TEMPERATURE NOT EXCEEDING 205*C, AND THEN SUBJECTING THEN TO SOLID STATE POLYMERIZATION REACTION AT A TEMPERATUE NOT EXCEEDING 205*C, THE MOLAR RATIO BETWEEN SAID DIISOCYANATE AND SAID TRICARBOXYLIC ANHYDRIDE BEING 1:1.
Inventors
- 👤 M Izumi
- 👤 S Matsumura
- 👤 N Asano
- 👤 M Kawaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 05:39
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/34; C08G18/343; C08G18/345; C08G73/00; C08G73/06; C08G73/10; C08G73/14; H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/307
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-08 | 1977-10-08 | 1978-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-08 | 1981-10-08 | 1982-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-08 | 1985-10-08 | 1986-04-09 | $7700.00 | Window Closed / Lapsed |