Automotive coating compositions

Claim 1

An automotive coating composition comprising (i) 100 parts by weight of a basal resin which is either (a) a copolymer containing a polysiloxane macro­monomer having two or more functional groups selected from the class consisting of hydroxyl and alkoxy groups per molecule and a number of average molecular weight of 40 to 100,000 as obtainable by reacting 70 to 99.999 mole percent of a compound (A) of the general formula: wherein R₁ is an aliphatic hydrocarbon group of 1 to 8 carbon atoms or a phenyl group; R₂, R₃ and R₄ in­dependently mean an alkoxy group of 1 to 4 carbon atoms or a hydroxyl group with 30 to 0.001 mole percent of a compound (B) of the general formula wherein R₅ is a hydrocarbon atom or a methyl group; R₆, R₇ and R₈ independently mean a hydroxyl group, an alkoxy group of 1 to 4 carbon atoms or an aliphatic hydrocarbon group of 1 to 8 carbon atoms; provided, however, that not all of R₆, R₇ and R₈ are aliphatic hydrocarbon groups of 1 to 8 carbon atoms; n is an integer equal to 1 to 6, inclusive, and an oxirane group-containing vinyl monomer as comonomer units or (b) a mixture of a polymer (I) containing said polysiloxane macromonomer as an essential monomer unit and a polymer (II) containing an oxirane group-­containing vinyl monomer as an essential monomer unit and (ii) 0.1 to 30 parts by weight of a chelate compound selected from the class consisting of aluminum chelate compounds, titanium chelate compounds and zirconium chelate compounds.