GB889585A - Process for dyeing nitrogenous fibres - Google Patents

Abstract

Nitrogenous fibres, such as wool, silk or polyamide fibres, are dyed or printed with a sulphonated copper phthalocyanine, which is free from reactive groups in the presence of a cation-active surface-active compound containing no polyglycol ether chains, particularly a quaternary ammonium compound, numerous examples of which are given. The dyebath may also contain a non-ionic dispersant, such as an ethylene oxide condensation product of a phenol, alcohol, fatty acid amide or alkylmercaptan, and an anion-active surface-active compound, such as sodium diisobutyl naphthalene sulphonate. Dyeing may be effected from an acidic or neutral bath at temperatures up to or above 100 DEG C. The dyebath may also contain sodium sulphate, and in the case of an acidic bath, the pH value is preferably raised by addition of, for example, an alkali metal bicarbonate, an ortho- or poly-phosphate, an ethanolamine, ammonia or hexamethylene tetramine, to a value above 6 after the fibres have absorbed the desired amount of dyestuff. In the latter case, a direct cotton dyestuff may be added to the bath after the pH has been raised, thereby enabling mixtures of nitrogenous fibres and cellulose fibres to be dyed from the same bath. Mixtures of differently sulphonated copper phthalocyanines or mixtures of sulphonated copper phthalocyanines with other dyestuffs, e.g. reactive dyestuffs, may be employed for dyeing the nitrogenous fibres.