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US3862157A
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2-(dialkylamino, pyrrolidino or piperidino)-3-amino-5-nitro pyridines
Assignee: Therachemie Chemische Therapeutische GmbH
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Filing: 1973-10-19
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Granted: 1975-01-21
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Expires: 1993-10-19
Abstract
Abstract A process for the dyeing of living human hair consisting essentially of treating human hair at a temperature of from about 10*C to 40*C with an aqueous solution containing a nitropyridine having the formula WHEREIN X and Y are amino or substituted amino groups, aqueous dyestuff compositions containing said nitropyridines and novel nitropyridines.
Inventors
- 👤 Erik Wiskott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:47
CPC Classifications
A; A61; A61Q; A61Q5/00; A61Q5/06; A61Q5/065; A61K; A61K8/00; A61K8/18; A61K8/30; A61K8/49; A61K8/4906; A61K8/4926
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
11 words
The 3-amino-5-nitropyridine of claim 1 wherein R3 and R4 are methyl.
Claim 2
Dependent Claim
13 words
The 3-amino-5-nitropyridine of claim 1 wherein R3 and R4 taken together are butylene.
Claim 3
Dependent Claim
13 words
The 3-amino-5-nitropyridine of claim 1 wherein R3 and R4 taken together are pentylene.
References Cited (Backward Citations)
US3574841A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |