US4078142A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Amino substituted-4-t-butylphthalic acid esters
Assignee: Standard Oil Co
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Filing: 1976-06-28
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Granted: 1978-03-07
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Expires: 1996-06-28
Abstract
Abstract Novel amino-substituted derivatives of 4-t-butylphthalic anhydride are used as monomers to produce novel polyimides with improved solubility characteristics. Increased solubility in organic solvents permits these polyimides to be used in coating applications where structurally similar polyimides could not otherwise be used.
Inventors
- 👤 Robert G. Keske
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:01
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
37 words
As a composition of matter, an amino-substituted ester of 4-t-butylphthalic anhydride, said ester having the general formula ##STR6## wherein R 1 and R 2 are individually selected from the group consisting of alkyl radicals and aryl radicals.
Claim 2
Dependent Claim
37 words
As a composition of matter, an amino-substituted ester of 4-t-butylphthalic anhydride, said ester having the general formula ##STR6## wherein R 1 and R 2 are individually selected from the group consisting of alkyl radicals and aryl radicals.
Claim 3
Dependent Claim
7 words
As a composition of matter, dimethyl 4-amino-5-t-butylphthalate.
Claim 4
Dependent Claim
7 words
As a composition of matter, dimethyl 4-amino-5-t-butylphthalate.
Claim 5
Dependent Claim
7 words
As a composition of matter, monomethyl 3-amino-5-t:butyl-phthalate.
Claim 6
Dependent Claim
7 words
As a composition of matter, monomethyl 3-amino-5-t:butyl-phthalate.
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) | 1981-03-06 | 1981-09-05 | 1982-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-03-06 | 1985-09-05 | 1986-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-03-06 | 1989-09-05 | 1990-03-07 | $7700.00 | Window Closed / Lapsed |