Process for reduction clearing of polyester-containing textiles

The invention concerns a process for the reductive post-cleaning of coloured or printed polyester-containing textiles and is characterized in that a mixture is added as a post-treatment agent to the acid dye liquor or the washing bath. Said mixture comprises as components: a) at least one compound of formula (I) Am[(CR R )mSO2M]p,q, in which A designates NR 3-q or OR 2-p, R , R , R designate hydrogen, C1-C6 alkyl, R designates identical or different groups selected from the group comprising hydrogen, C1-C20 alkyl, C3-C8 cycloalkyl, optionally substituted by between one and three C1-C4 alkyl groups, M is an equivalent of an ammonium, alkali or alkaline earth ion, m is 0 or 1, p is 1 or 2, q is 1, 2 or 3, at least one of the groups R , R , R being a C1-C6 alkyl when A stands for OR 2-p, and, when m equals 0: p, q assuming the value 2, and the compound of formula (I) is used in a mixture with an amount of acid-binding substance which is sufficient to increase the pH value of the dye liquor or washing bath by between 1 and 3 units; b) optionally at least one compound of formula (II) A[(CR R )SO3M]p,q, in which A, R , R , R , R , M, p and q have the same general meanings as in formula (I); and c) optionally further additives.