Process for producing polyisocyanate polyaddition products wherein a) at least one aliphatic, cycloaliphatic, araliphatic and/or aromatic polyisocyanate b) at least one NCO-reactive compound c) at least one inorganic catalyst comprising tin d) optionally further catalysts different from c) and/or activators e) optionally fillers, pigments, additives, thickeners, defoamers and/or other auxiliaries and additives and f) an at least equimolar amount, based on the catalyst specified under c), and at most an equimolar amount, based on the NCO-reactive groups of the compound of b), of a protic acid are reacted with one another, wherein the ratio of the weight of tin of component c) and the weight of component a) is less than 1000 ppm if component a) is an aliphatic polyisocyanate, and is less than 80 ppm if component a) is an aromatic polyisocyanate, characterized in that the catalysts c) used are cyclic tin compounds of the formula I, II or III: where n>1, where n>1, where D is -O-, -S- or -N(R 1)-, where R 1 is a saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or an optionally substituted aromatic or araliphatic radical having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or is hydrogen or the radical or R1 and L3 together are -Z-L 5, and D* is -O- or -S-, and X, Y and Z are the same or different radicals selected from alkylene radicals of the formulae -C(R 2)(R 3)-, -C(R 2)(R 3)-C(R 4)(R 5)- or -C(R 2)(R 3)-C(R 4)(R 5)-C(R 6)(R 7)- or ortho-arylene radicals of the formulae where R 2 to R 11 are each independently saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or are hydrogen, and L 1, L 2 and L 5 are each independently -O-, -S-, -OC(=O)-, -OC(=S)-, -SC(=O)-, -SC(=S)-, -OS(=O) 2 O-, -OS(=O) 2 - or -N -, where R 12 is a saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or an optionally substituted aromatic or araliphatic radical having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or is hydrogen, and; L 3 and L 4 are each independently -OH, -SH, -OR 13, - Hal, -OC(=O)R 14, -SR 15, -OC(=S)R 16, -OS(=O) 2 OR 17,-OS(=O) 2 R 18 or -NR 19 R 20, or L 3 and L 4 together are -L 1 -X-D-Y-L 2 -, where R 13 to R 20 are each independently saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or are hydrogen. a) at least one aliphatic, cycloaliphatic, araliphatic and/or aromatic polyisocyanate b) at least one NCO-reactive compound c) at least one inorganic catalyst comprising tin d) optionally further catalysts different from c) and/or activators e) optionally fillers, pigments, additives, thickeners, defoamers and/or other auxiliaries and additives and f) an at least equimolar amount, based on the catalyst specified under c), and at most an equimolar amount, based on the NCO-reactive groups of the compound of b), of a protic acid D is -O-, -S- or -N(R 1)-, where R 1 is a saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or an optionally substituted aromatic or araliphatic radical having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or is hydrogen or the radical or R1 and L3 together are -Z-L 5, and D* is -O- or -S-, and X, Y and Z are the same or different radicals selected from alkylene radicals of the formulae -C(R 2)(R 3)-, -C(R 2)(R 3)-C(R 4)(R 5)- or -C(R 2)(R 3)-C(R 4)(R 5)-C(R 6)(R 7)- or ortho-arylene radicals of the formulae where R 2 to R 11 are each independently saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or are hydrogen, and L 1, L 2 and L 5 are each independently -O-, -S-, -OC(=O)-, -OC(=S)-, -SC(=O)-, -SC(=S)-, -OS(=O) 2 O-, -OS(=O) 2 - or -N -, where R 12 is a saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or an optionally substituted aromatic or araliphatic radical having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or is hydrogen, and; L 3 and L 4 are each independently -OH, -SH, -OR 13, - Hal, -OC(=O)R 14, -SR 15, -OC(=S)R 16, -OS(=O) 2 OR 17,-OS(=O) 2 R 18 or -NR 19 R 20, or L 3 and L 4 together are -L 1 -X-D-Y-L 2 -, where R 13 to R 20 are each independently saturated or unsaturated, linear or branched, aliphatic or cycloaliphatic or optionally substituted aromatic or araliphatic radicals having up to 20 carbon atoms, which may optionally comprise heteroatoms from the series oxygen, sulfur, nitrogen, or are hydrogen.