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US4975331A
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Polyimide copolymers containing 4,4'-bis(p-aminophenoxy)biphenyl and siloxane diamine moieties
Assignee: Texas A&M University System
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Filing: 1990-05-24
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Granted: 1990-12-04
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Expires: 2010-05-24
Abstract
Abstract A low modulus, solvent resistant, wet etchable polyimide useful in electronic applications as passivation and insulating coatings, said polyimides containing a 4,4'-bis(p-aminophenoxy)biphenyl moiety, a siloxane diamine moiety, and a dianhydride moiety.
Inventors
- 👤 Marvin J. Burgess
- 👤 David A. Wargowski
- 👤 Agnes M. Palka
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:06
CPC Classifications
C; C08; C08G; C08G77/00; C08G77/42; C08G77/452; C08G77/455; C08G73/00; C08G73/06; C08G73/10; C08G73/1042; C08G73/1057; C08G73/106; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31678; Y10T428/31681; Y10T428/31721
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
54 words
A substrate structure coated with at least one layer of the polyimide composition comprising recurring units ##STR6## wherein Ar is at least one tetravalent aromatic nucleus; R is a divalent hydrocarbon radical; R 1 is a monovalent hydrocarbon radical; m and n are each at least one; and x is 1 to about 50.
Claim 2
Dependent Claim
54 words
A substrate structure coated with at least one layer of the polyimide composition comprising recurring units ##STR6## wherein Ar is at least one tetravalent aromatic nucleus; R is a divalent hydrocarbon radical; R 1 is a monovalent hydrocarbon radical; m and n are each at least one; and x is 1 to about 50.
Claim 3
Dependent Claim
21 words
A multilayer structure comprising at least one substrate coated with one or more layers of the polyimide composition of claim 1.
Claim 4
Dependent Claim
79 words
A substrate coated with at least one layer of the polyamic acid composition comprising recurring units ##STR7## wherein Ar is at least one tetravalent aromatic nucleus; R is a divalent hydrocarbon radical; R 1 is a monovalent hydrocarbon radical; r and s are at least one; y is 1 to about 50; R 2 and R 3 are independently selected from halogen, --OH, and --OR 4; and R 4 is an alkyl group of 1 to 4 carbon atoms.
Claim 5
Dependent Claim
79 words
A substrate coated with at least one layer of the polyamic acid composition comprising recurring units ##STR7## wherein Ar is at least one tetravalent aromatic nucleus; R is a divalent hydrocarbon radical; R 1 is a monovalent hydrocarbon radical; r and s are at least one; y is 1 to about 50; R 2 and R 3 are independently selected from halogen, --OH, and --OR 4; and R 4 is an alkyl group of 1 to 4 carbon atoms.
Claim 6
Dependent Claim
22 words
A multilayer structure comprising at least one substrate coated with one or more layers of the polyamic acid composition of claim 3.
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) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |