Aqueous polyurethane-polyurethane urea dispersions, adhesives containing the same, processes for the preparation thereof and uses therefore

An aqueous polyurethane-polyurethane urea dispersion comprising a reaction product of:

• (i) an NCO prepolymer prepared by reacting;
• (A) one or more di- or higher-functional polyols having a mean molecular weight of 400 to 5000 daltons, (B) optionally one or more di- or higher-functional polyol components having a molecular weight of from 62 to 399 daltons, and (C) one or more di- or poly-isocyanate components;
• and
• (ii) a mixture (D) of primary and/or secondary monoamino compounds (D1) and primary and/or secondary diamino compounds (D2);
• wherein at least one of the amino compounds of the mixture (D) is selected from the group consisting of the sodium or potassium salts of N-(2-aminoethyl)-2-aminoethanesulfonic acid, of N-(3-aminopropyl)-2-aminoethanesulfonic acid, of N-(3-aminopropyl)-3-aminopropanesulfonic acid, and of N-(2-aminoethyl)-3-aminopropanesulfonic acid or of the analogous carboxylic acids;
• wherein mixture (D) has a mean amino functionality of 1.65 to 1.95;
• and wherein the equivalent ratio of NCO groups in the NCO prepolymer to the total amount of isocyanate-reactive amino and hydroxyl groups of the mixture (D) is 1.04 to 1.9.