Coatings for thermoplastics

Claim 1

A coating composition consisting of approximately (A) 10-40% by weight, relative to the total weight of the coating composition, of a partially hydrolyzed, siloxane compound which is obtained by hydrolysis in water at about 50°-80° C. for a period of about 1 to 12 hours of at least one of (a), (b), (c) or (d), wherein (a) is a hydrocarbon trialkoxysilane of the formula R'Si(OR").sub.3' wherein R' denotes an alkyl group having 1 to 4 carbon atoms, a phenyl group or vinyl group and R" denotes an alkyl group having 1 to 4 carbon atoms, (b) is a co-condensation product of (a) and 1 to 40% of a phenyltrialkoxysilane or vinyltrialkoxysilane, wherein the alkoxy group contains 1 to 4 carbon atoms, (c) is a co-condensation product of 1 mol of (a) and 0.05 to 1 mol of a tetraalkoxysilane, wherein the alkoxy group contains 1 to 4 carbon atoms, and (d) is a co-condensation product of 1 mol of (a) and 0.05 to 1 mol of a dialkyldialkoxysilane, wherein the alkyl and alkoxy groups contain 1 to 4 carbon atoms, (B) 0 to 40% by weight, relative to the total weight of the coating compositions, of an aqueous dispersion of colloidal silicon dioxide. (C) 0 to 5% by weight, relative to the total weight of the coating agent, of an etherified methylolmelamine, (D) 0.05 to 15% by weight, relative to the total weight of the coating composition, of a blocked polyisocyanate, (E) 0.5 to 30% by weight, relative to the total weight of the coating composition, of acetic acid, and (F) 0.05 to 4% by weight, relative to the total weight of the coating composition, of a polysiloxane which is terminated by hydroxyl group, has an average chain length of between 1 to 25 and a molecular weight of 150 to 1800, and (G) an inert organic solvent as the remainder.