Process for the preparation of a water soluble direct green polyazo dyestuffs mixture in situ and water soluble direct green polyazo dyestuffs mixture obtained thereby
AssigneeThe Atul Products Limited
InventorsNagajibhai T. Patel, Subrao S. Kulkarni, Garish I. Bhatt
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Abstract
A process for the preparation of a water soluble direct green polyazo dyestuffs mixture in situ comprising phosgenation of a mordant yellow dye and an acid green dye using phosgene gas in an aqueous alkaline medium at a temperature between 50.degree. C. to 80.degree. C. and isolating or recovering the dyestuffs mixture from the phosgenation reaction mass and water soluble direct green polyazo dyestuffs mixture obtained thereby.
Claims16
A process for the preparation of a water soluble direct green polyazo dyestuffs mixture of the formulae, ##STR1## and said process comprising phosgenation of 1 part by weight of mordant yellow dye of the formula, ##STR2## and 3 to 12 parts by weight of acid green dye of the formula, ##STR3## using phosgene gas of the formula COCl.sub.2, in an aqueous alkaline medium at a temperature between 50.degree. C. to 80.degree. C. to form a dyestuffs mixture of the said formulae, ##STR4## and in situ and isolating or recovering the said mixture from the phosgenation reaction mass, wherein R is hydrogen, sodium or potassium and X is methyl, ethyl, methoxy, ethoxy, chloro, nitro, carboxy, sulphonic or hydrogen at the 2, 3 or 4 position.
Dependencies are inferred from the claim text.