Process for dyeing paper
AssigneeCiba-Geigy Corporation
InventorAdolf Kaser
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Abstract
A process for dyeing paper which comprises the use of dyes of the formula ##STR1## wherein R is hydrogen, hydroxyl or amino, X is the azoxy or azo group, and n is 1 or 2, and the bonds of the complexing oxygen atom in the .alpha.-position and of the azo group in the .beta.-position at the naphthalene nuclei are mutually interchangeable. Dyeings of good wetfastness and lightfastness are obtained.
Claims3
A process for dyeing paper which comprises applying to the paper a dye of the formula ##STR5## wherein R is hydrogen, hydroxyl or amino, X is azoxy or azo, and n is 1 or 2, and the bond of the complexing oxygen atom in the .alpha.-position and the bond of the azo group in the .beta.-position at each of the naphthalene nuclei are interchangeable.
Paper dyed by the process which comprises applying to the paper a dye of the formula ##STR7## wherein R is hydrogen, hydroxyl or amino, X is azoxy or azo, and n is 1 or 2, and the bond of the complexing oxygen atom in the .alpha.-position and the bond of the azo group in the .beta.-position at each of the naphthalene nuclei are interchangeable.
Dependencies are inferred from the claim text.