Abstract: Aqueous dispersions which are suitable for the treatment of leather and have a pH of from 2 to 7 and particle diameters of from 20 to 150 nm of polymers having a T.sub..lambda.max -value below 20.degree. C. ofA from 20 to 70 parts by weight of one or more acyclic conjugated dienes having from 4-9 carbon atoms;B from 10 to 40 parts by weight of acrylonitrile and/or methacrylonitrile;C from 1 to 5 parts by weight of allylsulphonic acid and/or methallyl sulphonic acid or water-soluble salts thereof;D less than 20 parts by weight of acrylic and/or methacrylic acid hydroxyalkylesters having from 2-4 carbon atoms in the hydroxyalkyl group; andE 0 to 40 parts by weight of acrylic and/or methacrylic acid alkyl esters having up to 8 carbon atoms in the alkyl group.

Abstract: The present invention relates to moisture-hardening one-component lacquers having improved shelf life and thermal stability. These lacquers are characterized by high gloss and high flexural strength and are based on reaction products containing free isocyanate groups of relatively high molecular weight polyols having an average functionality of from 2 to 3, polyisocyanates and, optionally, low molecular weight polyhydroxyl compounds which are characterized in that the relatively high molecular weight polyol is a mixture of:(a) a hydroxyl polyester having an average molecular weight of from about 500 to 6000,(b) a hydroxyl polyether corresponding to the following general formula: ##STR1## wherein R.sub.1 represents hydrogen, a C.sub.1 -C.sub.4 alkyl radical or a phenyl radical,X represents one of the difunctional radicals --S--, --O--, --SO.sub.2 --, --CO-- or --C(R.sub.2 R.sub.3)-- whereR.sub.2 and R.sub.3, which may be the same or different, represent hydrogen or a C.sub.1 -C.sub.