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Abstract

The invention relates to a method for producing aqueous polyurethane-polyurea dispersions, where A) first a polyurethane prepolymer containing NCO groups is produced by reacting A1) polyisocyanates with A2) polymeric polyols and/or polyamines having number-average molecular weights of more than 400 to 8,000 g/mol, A3) possibly low-molecular-weight compounds having number-average molecular weights of 17-400 g/mol selected from the group comprising mono- and polyalcohols, mono- and polyamines, and amino alcohols, A4) isocyanate-reactive, ionically or potentially ionically hydrophilic compounds and/or isocyanate-reactive non-ionically hydrophilic compounds, A5) isocyanate-reactive compounds, which contain at least one C₇ to C₂₄ alkyl group or C₇ to C₂₄ alkenyl group, and A6) isocyanate-reactive compounds, which contain at least one polysiloxane group, and B); the NCO groups of the prepolymer that are not yet free are reacted with isocyanate-reactive monoamines, polyamines, hydrazine, and/or hydrazides, dimensioned in such a way that a calculated ratio of the isocyanate-reactive NH groups to the NCO groups of 0.7 to 1.2 is achieved.

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First Claim