The present invention relates to the use in washing and cleaning agents of one or a plurality of polyesters which can be obtained by polymerisation of a) terephthalic acid dimethyl ester, and b) ethylene glycol, and c) 1,2-propylene glycol, and d) one or a plurality of polyethylene glycols with mass-average molecular weights in the range from 1000 to 2000 g/mol, and e) a methyl polyethylene glycol with a mass-average molecular weight in the range from 1050 to 1350 g/mol, f) either in the presence of or in the absence of one or a plurality of cross-linking compounds with 3 to 6 polycondensation-capable functions. The polyesters are particularly suited for use in the washing and cleaning agents as dispersants or as soil release polymers.