The preparation of polyurethane soft foams involves using polyester polyols as the polyol component and compound containing silicon atoms and polyether chains. The preparation of polyurethane (PU) soft foams comprises reacting polyisocyanates comprising isocyanate and urethane group-containing prepolymers from diphenylmethane diisocyanate, polyphenyl polymethylene polyisocyanates and polyether polyols with compounds with at least two active hydrogen atoms from polyester polyols in the presence of propellants, catalysts and additives and aids containing silicon atoms and polyether chains. SPECIFIC SUBSTANCES - The polyester polyols have a functionality of 2-4 and a mol. wt. of 1800-3600.
