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US5013840A
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Polyamic acid or polyimide
Assignee: Polyplastics Co Ltd
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Filing: 1989-12-20
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Granted: 1991-05-07
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Expires: 2009-12-20
Abstract
Abstract A polyamic acid or polyimide having 2,5-distyrylpyrazine units in the main chain thereof.
Inventors
- 👤 Takuma Teshirogi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:24
CPC Classifications
C; C07; C07D; C07D241/00; C07D241/02; C07D241/10; C07D241/12; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1085
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
39 words
A polyamic acid or a polyimide represented by the following formula [XI] ##STR12## Ar is an aromatic tetrafunctional residue selected from the group consisting of ##STR13## and a mixture thereof, and n is an integer of 2 to 50.
Claim 2
Dependent Claim
39 words
A polyamic acid or a polyimide represented by the following formula [XI] ##STR12## Ar is an aromatic tetrafunctional residue selected from the group consisting of ##STR13## and a mixture thereof, and n is an integer of 2 to 50.
Claim 3
Dependent Claim
37 words
A polyamic acid represented by the following formula [XIV] ##STR14## wherein Ar is an aromatic tetrafunctional residue selected from the group consisting of ##STR15## and a mixture thereof, and n is an integer of 2 to 50.
Claim 4
Dependent Claim
37 words
A polyamic acid represented by the following formula [XIV] ##STR14## wherein Ar is an aromatic tetrafunctional residue selected from the group consisting of ##STR15## and a mixture thereof, and n is an integer of 2 to 50.
Claim 5
Dependent Claim
36 words
A polyimide represented by the following formula [XV] ##STR16## wherein Ar is an aromatic tetrafunctional residue selected from the group consisting of ##STR17## and a mixture thereof, and n is an integer of 2 to 50.
Claim 6
Dependent Claim
36 words
A polyimide represented by the following formula [XV] ##STR16## wherein Ar is an aromatic tetrafunctional residue selected from the group consisting of ##STR17## and a mixture thereof, and n is an integer of 2 to 50.
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) | 1994-05-06 | 1994-11-05 | 1995-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-06 | 1998-11-05 | 1999-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-06 | 2002-11-05 | 2003-05-07 | $7700.00 | Window Closed / Lapsed |