Patent ID: 6984262

Claim:
A coating composition adapted to enhance the adhesion of a polymeric coating applied to a substrate, said coating composition comprising: a) at least one silane coupling agent, at least partial hydrolysates thereof or mixtures thereof, in a concentration greater than 25 weight percent, based on the weight of the total composition, represented by the following formula: (R 1 ) a (R 2 ) b Si(OR 3 ) c wherein each R 1 is an organofunctional group chosen from mercapto, glycidoxy, (meth)acryloyloxy, or a hydrocarbon radical chosen from C 1 –C 6 alkyl or phenyl, said hydrocarbon radical being substituted with said organofunctional group; each R 2 is a hydrocarbon radical having less than 20 carbon atoms independently chosen for each occurrence from aliphatic radicals, aromatic radicals or mixtures of such hydrocarbon radicals; each R 3 is C 1 –C 6 alkyl, phenyl, acetyl or benzoyl; a is 1, b is 0 and c is 3; and b) an adhesion enhancing amount of an epoxy-containing material comprising at least two epoxy groups; said coating composition being substantially free of photochromic material and colloidal particles chosen from silica, alumina or mixtures thereof.