Process for the level dyeing of synthetic fiber materials

Claim 1

A process for the level dyeing of fiber material made from linear polyesters and from mixtures thereof with natural fibers, with water insoluble disperse dyestuffs according to the exhaust method, which comprises adding to the aqueous dyebath, in addition to the said dyestuffs and pH regulating substances, as levelling agents in an amount of 0.1-5 grams per liter a water soluble or dispersible linear polyester which has the general formula ##STR18## in which m is zero or 1, n is a number such that the average molecular weight of the polyester is 800-5,000, each X, which may be the same or different, is H, --O--CH 2 --CH 2 --CH 2 --SO 3 M or --SO 3 M, in which M is hydrogen or alkali metal or ammonium or substituted ammonium, and each R, which is the same or different, is a diol radical of 2-10 carbons of a saturated or unsaturated aliphatic, cycloaliphatic or aromatic compound and in which the meaning of X is balanced such that 5-30 mole % of all phenylene nuclei in formula I carry a sulfato-containing radical.