The invention relates to the use of cationic polycondensation products as additives for fixing colors and/or inhibiting the running of colors, for washing products and washing aftertreatment products. Said cationic polycondensation products can be produced by the condensation of (A1) non-cyclic amines obtained by the reaction of (A1 a) mono(N,N-dialkylaminoalkyl)amines with (A1 b) bifunctional compounds selected from the group containing urea, thiourea, dialkyl carbonates, aliphatic and aromatic dicarboxylic acids, and aliphatic and aromatic diisocyanates, in a molar ratio 1.2:1 to 2.1:1, or (A2) mixtures of non-cyclic amines (A1) and cyclic amines (A3) in a molar ratio 10:1 to 1:10 with (B) bifunctional compounds selected from the group containing alkylene dihalogenides, dihalogen alkyl ethers, halomethyl oxiranes, and bisepoxides, in a molar ratio (B) to (A1) or (B) to (A2) from 0.6:1 to 1.3:1.