PURPOSE: To obtain the subject composition capable of forming a coating film excellent in abrasion resistance on the surface of a thermoplastic resin molding by dissolving a specified copolymer containing a specified alkoxysilylated monomer, an alkyl acrylate polymer, a crosslinking agent, and an ultraviolet absorber in an organic solvent.

CONSTITUTION: 100 pts.wt. organic copolymer of an alkoxysilylated acrylic and/or vinyl monomer (e.g. 3-methacryloxypropyltrimethoxysilane and vinyltrimethoxysilane), vinyl acetate, and other monomer copolymerizable therewith [e.g. methyl (meth)acrylate], 10-100 pts.wt. 1-8C alkyl (meth)acrylate (co)polymer, 20-100 pts.wt. crosslinking agent for the alkoxysilylated copolymer, and 10-100 pts.wt. ultraviolet absorber are dissolved in an organic solvent to give a primer composition for forming an abrasion-resistant silicone coating film excellent in adhesiveness, durability and weather resistance on the surface of a molding of a thermoplastic resin such as polycarbonate.