Coloring polyester materials with acid dyes

A material consisting essentially of polyester modified by pre-treatment at a relatively elevated temperature with a mixture of (a) an organic nitrogen compound selected from the group consisting of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hexamethylenediamine, hexamethylenetetramine, mono-, di- and triethanolamine, triethylamine, di- and tripropylamine, and di- and tributylamine, and (b) a glycol selected from the group consisting of ethylene glycol, di-, tri- and tetraethylene glycol, and polypropylene glycol, and thereafter chilled by contact with cold water or a mixture of cold water and a carboxylic acid selected from the group consisting of oxalic acid, sebacic acid, citric acid, and adipic acid, the thus pre-treated polyester material possessing a strong affinity for acid dyes.

A process for coloring a material consisting essentially of polyester with acid dyes, which comprises pre-treating the polyester material for a brief time less than about one minute at a temperature between 90.degree. C and 250.degree. C and at ordinary atmospheric pressure with a mixture of (a) an organic nitrogen compound selected from the group consisting of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hexamethylenediamine, hexamethylenetetramine, mono-, di- and triethanolamine, triethylamine, di- and tripropylamine, and di- and tributylamine, and (b) a glycol selected from the group consisting of ethylene glycol, di-, tri- and tetraethylene glycol, and polypropylene glycol, chilling the polyester material with cold water or a mixture of cold water and a carboxylic acid selected from the group consisting of oxalic acid, sebacic acid, citric acid, and adipic acid sufficiently to chill the polyester material, thereby imparting to the thus pre-treated polyester material an affinity for acid dyes;

• and then coloring the thus pre-treated polyester material by padding, printing or cascading an acid dye from an aqueous solution or printing paste and thereby effecting fixation of said acid dye on the thus pre-treated polyester material with uniform distribution thereof within the polyester material.

An acid-dyed material consisting essentially of acid-dyed polyester that has been first modified by treatment at a relatively elevated temperature with a mixture of (a) an organic nitrogen compound selected from the group consisting of diethylenetriamine, triethylenetetramine, tetraethylenepentamine, hexamethylenediamine, hexamethylenetetramine, mono-, di- and triethanolamine, triethylamine, di- and tri-propylamine, and di- and tributylamine, and (b) a glycol selected from the group consisting of ethylene glycol, di-, tri- and tetraethylene glycol, and polypropylene glycol, and thereafter chilled by contact with cold water or a mixture of cold water and a carboxylic acid selected from the group consisting of oxalic acid, sebacic acid, citric acid, and adipic acid.