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Abstract

The present invention relates to a process for the production of aqueous polyurethane-polyurea dispersions comprising the steps of:

A) reacting primary and/or secondary monoamines or diamines A1) with cyclic carbonate containing one hydroxy group A2) such that the molar ratio of total primary and/or secondary amine groups to cyclic carbonate groups is in the range of 0.8 to 1.2;B) producing an NCO-containing polyurethane prepolymer by reacting B1) polyisocyanates with B2) polymeric polyols and/or polyamines having number average molecular weights of more than 400 to 8,000 g/mol, optionally B3) low molecular weight compounds having number average molecular weights of 17-400 g/mol selected from the group consisting of mono- and polyalcohols, mono- and polyamines, and aminoalcohols; optionally B4) isocyanate-reactive, ionically hydrophilizing compounds, and B5) the reaction products of A);C) dispersing the prepolymer from B) in water; andD) optionally reacting the remaining free NCO groups of the prepolymer from B) with monoamines, polyamines, hydrazine and/or hydrazides, wherein the molar ratio of the NH groups to the NCO groups is from 0 to 1.2, and step D) occurs partially or completely prior to or during the dispersion step C).

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First Claim