Process for dyeing polyamidic textile materials, in particular high dyeing speed polyamides with acid dyes and alkaline reactants
AssigneeSnia Viscosa Societa' Nazionale Industria Applicazioni Viscosa S.p.A.
InventorsEugenio Magni, Claudio Pernetti
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Abstract
A process is described for the fast dyeing of textile materials constitut at least to a significant degree, by polyamides, in particular quick dyeing polyamides, characterized in that a dye bath is employed comprising acid dyes to which a combination of reagents (e.g. ammonium sulphate and caustic soda) is added that is adapted to impart to the bath an initial alkaline pH and to lower the pH by elimination of volatile bases, at least at the final heating temperatures, and in that the bath is heated until final temperatures between 60.degree. C. and 80.degree. C. are attained.
Claims17
A process for dyeing quick dyeing synthetic polyamides consisting essentially of dyeing said polyamides in a bath containing acid dyes, an ammonium salt and an alkali metal hydroxide, and having an initial pH between 8 and 9.5, and heating said bath to a final temperature of 60.degree. C., said alkali metal hydroxide and said ammonium salt being added in an amount sufficient to lower the pH of the bath, at the final temperature by 0.5-0.9.
Dependencies are inferred from the claim text.