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US 4,062,645 AGranted
Acid dyes useful for dyeing streaked nylon
AssigneeMontedison S.p.A.
InventorsRoberto Cipolli, Giampiero Pieri, Camillo Paffoni
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Abstract
The known compounds of the formula: ##STR1## wherein X is hydrogen or bromine, Y is hydrogen, chlorine, bromine or methyl and the -COOH group is meta or para to the azo group have been found to be useful in uniformly dyeing polyamide fibers to a yellow shade.
Claims1
A process for imparting an equalized yellow shade to streaked polyamide fibers comprising dyeing said fibers with a dyestuff having the formula:
- ##STR9## wherein X is hydrogen or bromine, Y is hydrogen, chlorine, bromine or methyl and the --COOH group is meta or para with respect to the azo group in an aqueous bath having a pH value between 8.5 and 9, heating the bath to boiling and then decreasing the pH value to between 5 and 6.5 by adding acetic acid.
Dependencies are inferred from the claim text.