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US4977232A
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Aromatic polyamide from 2,2'-bis(4-(4-amino-phenoxy)phenyl)hexafluoro propane
Assignee: Central Glass Co Ltd
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Filing: 1988-08-03
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Granted: 1990-12-11
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Expires: 2008-08-03
Abstract
Abstract Novel aromatic polyamides high in heat resistance and soluble in various organic solvents are obtained each by reacting 2,2'-bis[4-(4-aminophenoxy)phenyl]-hexafluoropropane or a simple derivative thereof with an aromatic dicarboxylic acid, e.g. isophthalic acid, or its dihalide or diester.
Inventors
- 👤 Yutaka Maruyama
- 👤 Haruhiko Komoriya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 02:23
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/26
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
79 words
An aromatic polyamide having a repeating unit structure represented by the formula (1): ##STR10## wherein R 1 , R 2 , R 3 and R 4 are the same or different and each represents a hydrogen atom, an alkyl group having not more than 6 carbon atoms, an alkoxyl group having not more than 6 carbon atoms, a chlorine atom, a fluorine atom or a bromine atom, R is ##STR11## and n is an integer from 2 to 200.
Claim 2
Dependent Claim
79 words
An aromatic polyamide having a repeating unit structure represented by the formula (1): ##STR10## wherein R 1 , R 2 , R 3 and R 4 are the same or different and each represents a hydrogen atom, an alkyl group having not more than 6 carbon atoms, an alkoxyl group having not more than 6 carbon atoms, a chlorine atom, a fluorine atom or a bromine atom, R is ##STR11## and n is an integer from 2 to 200.
Claim 3
Dependent Claim
25 words
An aromatic polyamide according to claim 1, wherein each of R 1 , R 2 , R 3 and R 4 is a hydrogen atom.
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) | 1993-12-10 | 1994-06-11 | 1994-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-10 | 1998-06-11 | 1998-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-10 | 2002-06-11 | 2002-12-11 | $7700.00 | Window Closed / Lapsed |