Nonaqueous coating material composition comprising at least one polyhydroxyl group-containing compound, at least one polyisocyanate group-containing compound having free or blocked isocyanate groups, which has at least one structural unit of the formula -NR-(X-SiR''x(OR')3-x), and/or at least one structural unit of the formula -N(X-SiR''x(OR')3-x)n(X'-SiR''y(OR')3-y)m, where R = alkyl, cycloalkyl, aryl or aralkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, where Ra = alkyl, cycloalkyl, aryl or aralkyl, R' = hydrogen, alkyl or cycloalkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, preferably R' = ethyl and/or methyl, X, X' = linear and/or branched alkylene or cycloalkylene radical having 1 to 20 carbon atoms, preferably X, X' = alkylene radical having 1 to 4 carbon atoms, R" = alkyl, cycloalkyl, aryl, or aralkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, preferably R" = alkyl radical, more particularly having 1 to 6 C atoms, n = 0 to 2, m = 0 to 2, m+n = 2, and x, y = 0 to 2, and as catalyst at least one phosphoric acid compound blocked with an amine or phosphonic acid compound blocked with an amine, or mixtures of these compounds, characterized in that the coating material composition further comprises at least one monomeric aromatic optionally substituted carboxylic acid whose carboxyl group is in conjugation with a π-electron system. at least one polyhydroxyl group-containing compound, at least one polyisocyanate group-containing compound having free or blocked isocyanate groups, which has at least one structural unit of the formula -NR-(X-SiR''x(OR')3-x), and/or at least one structural unit of the formula -N(X-SiR''x(OR')3-x)n(X'-SiR''y(OR')3-y)m, where R = alkyl, cycloalkyl, aryl or aralkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, where Ra = alkyl, cycloalkyl, aryl or aralkyl, R' = hydrogen, alkyl or cycloalkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, preferably R' = ethyl and/or methyl, X, X' = linear and/or branched alkylene or cycloalkylene radical having 1 to 20 carbon atoms, preferably X, X' = alkylene radical having 1 to 4 carbon atoms, R" = alkyl, cycloalkyl, aryl, or aralkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, preferably R" = alkyl radical, more particularly having 1 to 6 C atoms, n = 0 to 2, m = 0 to 2, m+n = 2, and x, y = 0 to 2, and R = alkyl, cycloalkyl, aryl or aralkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, where Ra = alkyl, cycloalkyl, aryl or aralkyl, R' = hydrogen, alkyl or cycloalkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, preferably R' = ethyl and/or methyl, X, X' = linear and/or branched alkylene or cycloalkylene radical having 1 to 20 carbon atoms, preferably X, X' = alkylene radical having 1 to 4 carbon atoms, R" = alkyl, cycloalkyl, aryl, or aralkyl, it being possible for the carbon chain to be interrupted by nonadjacent oxygen, sulfur or NRa groups, preferably R" = alkyl radical, more particularly having 1 to 6 C atoms, n = 0 to 2, m = 0 to 2, m+n = 2, and x, y = 0 to 2, as catalyst at least one phosphoric acid compound blocked with an amine or phosphonic acid compound blocked with an amine, or mixtures of these compounds, at least one monomeric aromatic optionally substituted carboxylic acid whose carboxyl group is in conjugation with a π-electron system.