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US3867392A
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Hydroxy-pyridone-monosulfonic acids
Assignee: Cassella Farbwerke Mainkur AG
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Filing: 1972-04-06
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Granted: 1975-02-18
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Expires: 1992-04-06
Abstract
Abstract 4-SUBSTITUTED-6-HYDROXY-2-PYRIDONE-5-SULFONIC ACIDS WHICH MAY BE OPTIONALLY SUBSTITUTED IN THE 1- AND 3-POSITIONS, PREPARATION THEREOF FROM THE CORRESPONDING 6-HYDROXY-2-PYRIDONE DERIVATIVES BY SULFONATION AND UTILITY THEREOF IN THE PREPARATION OF DYESTUFFS.
Inventors
- 👤 Ernst Heinrich
- 👤 Rolf Muller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 07:30
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/62; C07D213/70; C07D213/71; C07D213/78; C07D213/84; C07D213/85; C09; C09B; C09B29/00; C09B29/34; C09B29/36; C09B29/3604; C09B29/3617; C09B29/3621; C09B29/3626; Y; Y10; Y10S; Y10S8/00; Y10S8/916; Y10S8/917; Y10S8/918
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
5 words
HYROXY-PYRIDONE-ONOSULFONIC ACIDS OF THE FORMULA
Claim 2
Dependent Claim
5 words
HYROXY-PYRIDONE-ONOSULFONIC ACIDS OF THE FORMULA
Claim 3
Dependent Claim
31 words
The hydroxy-pyridone-monosulfonic acids of claim 1 wherein X is alkyl having 1 to 4 carbon atoms, Y is hydrogen and Z is hydrogen, or alkyl having 1 to 4 carbon atoms.
Claim 4
Dependent Claim
16 words
The hydroxy-pyridone-monosulfonic acids of claim 2 wherein X is alkyl having 1 to 2 carbon atoms.
Claim 5
Dependent Claim
16 words
The hydroxy-pyridone-monosulfonic acids of claim 2 wherein Z is alkyl having 1 to 2 carbon atoms.
Claim 6
Dependent Claim
16 words
The hydroxy-pyridone-monosulfonic acids of claim 1 wherein X is methyl and Y and Z are hydrogen.
Claim 7
Dependent Claim
16 words
The hydroxy-pyridone-monosulfonic acids of claim 1 wherein X and Z are methyl and Y is hydrogen.
References Cited (Backward Citations)
US3725383A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-02-17 | 1978-08-19 | 1979-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-02-17 | 1982-08-19 | 1983-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-02-17 | 1986-08-19 | 1987-02-18 | $7700.00 | Window Closed / Lapsed |