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US4530993A
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Poly 2,2'-dichloro-4,4'-biphenylene pyromellitimide film
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1984-11-02
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Granted: 1985-07-23
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Expires: 2004-11-02
Abstract
Abstract Disclosed is a polyimide film consisting essentially of 2,2'-dichloro-4,4'-biphenylene pyromellitimide units. This film has high tensile characteristics and excellent heat resistance.
Inventors
- 👤 Takuma Jinda
- 👤 Toshikazu Matsuda
- 👤 Masanori Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:52
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; C08J2379/00; C08J2379/04; C08J2379/08
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
9 words
A polyimide film consisting essentially of 2,2'-dichloro-4,4'-biphenylene pyromellitimide units.
Claim 2
Dependent Claim
9 words
A polyimide film consisting essentially of 2,2'-dichloro-4,4'-biphenylene pyromellitimide units.
Claim 3
Dependent Claim
36 words
A polyimide film as set forth in claim 1, which is an in-plane isotropic film having a tensile strength of at least 20 kg/mm 2 and an elastic modulus of at least 1000 kg/mm 2 .
Claim 4
Dependent Claim
36 words
A polyimide film as set forth in claim 1, which is a monoaxially drawn film having a tensile strength of at least 30 kg/mm 2 and an elastic modulus of at least 3000 kg/mm 2 .
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) | 1988-07-22 | 1989-01-21 | 1989-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-22 | 1993-01-21 | 1993-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-22 | 1997-01-21 | 1997-07-23 | $7700.00 | Window Closed / Lapsed |