US3821161A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aromatic diimides of 3,5-dialkyl-4-hydroxyphenylsubstituted amines
Assignee: Novartis Corp
•
Filing: 1973-01-18
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Granted: 1974-06-28
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Expires: 1993-01-18
Abstract
Abstract Aromatic diimides of 3,5-dialkyl-4-hydroxyphenylsubstituted amines of this invention effectively stabilize organic polymeric materials against the effects of heat and oxygen. The diimides of this invention are prepared by reacting the appropriate 3,5dialkyl-4-hydroxyphenylsubstituted amine with an aromatic dianhydride or aromatic diimide. An example of this class of stabilizer is N,N''-bis(3,5-di-t-butyl-4-hydroxybenzyl)diphenyl sulfone-3,4,3'',4''-tetracarboxylic acid diimide.
Inventors
- 👤 J Stephen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:42
CPC Classifications
C; C07; C07D; C07D209/00; C07D209/02; C07D209/44; C07D209/48; C08; C08K; C08K5/00; C08K5/16; C08K5/34; C08K5/3412; C08K5/3415; C08K5/3417
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
14 words
The composition of claim 1 wherein R1 and R2 is tertiary butyl or methyl.
Claim 2
Dependent Claim
14 words
The composition of claim 2 wherein the stabilizing compound is N,N''-bis-(3,5-di-t-butyl-4-hydroxybenzyl)4,4''-isopropylidene diphthalic acid diimide.
Claim 3
Dependent Claim
14 words
The composition of claim 2 wherein the stabilizing compound is N,N''-bis-(3,5-di-t-butyl-4-hydroxybenzyl)diphenylsulfone-3,4, 3'',4''-tetracarboxylic acid diimide.
Claim 4
Dependent Claim
14 words
The composition of claim 2 wherein the stabilizing compound is N,N''-bis-(3,5-di-t-butyl-4-hydroxybenzyl)diphenylether-3,4,3'', 4''-tetracarboxylic acid diimide.
Claim 5
Dependent Claim
14 words
The composition of claim 2 wherein the stabilizing compound is N,N''-bis(3,5-di-t-butyl-4-hydroxybenzyl)diphenylmethane-3,4, 3'',4''-tetracarboxylic acid diimide.
Claim 6
Dependent Claim
15 words
The composition of claim 2 wherein the stabilizing compound is N,N''-bis(3-methyl-5-t-butyl-4-hydroxybenzyl)diphenylether 3,4, 3'',4''-tetracarboxylic acid diimide.
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) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |