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US3867392A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydroxy-pyridone-monosulfonic acids

Assignee: Cassella Farbwerke Mainkur AG
•
Filing: 1972-04-06
•
Granted: 1975-02-18
•
Expires: 1992-04-06
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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 07:07
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

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