A coating composition comprising surface-treated titanium oxide comprising 100 parts by weight of core/shell type microparticles each consisting of a core of titanium oxide, optionally complexed with another inorganic oxide, and a shell of silicon oxide around the core, obtainable by treatment of said core/shell microparticles with 11 to 200 parts by weight of both surface treating component having the general formula and surface treating component having the general formula: R 1 Si(OR 2) 3 wherein R 1 is a C 1 -C 15 organic group which may have a (meth) acrylic moiety, and R 2 are C 1 -C 4 alkyl, (R 3 R 4 2 Si) 2 NH wherein R 3 are C 1 -C 15 organic group which may have a (meth) acrylic moiety, and R 4 are C 1 -C 6 alkyl, vinyl copolymer having alkoxysilyl and organic UV-absorbing groups attached on side chains and obtainable from copolymerization of (b-1) 1 to 50% by weight of vinyl monomer having an alkoxysilyl group, (b-2) 5 to 40% by weight of vinyl monomer having an organic UV-absorbing group and vinyl polymerizable group in the molecule, comprising benzotriazole compound having the general formula: wherein X is hydrogen or chlorine, R 11 is hydrogen, methyl, or a tertiary C 4 -C 8 alkyl group, R 12 is a straight or branched C 2 -C 10 alkylene group, R 13 is hydrogen or methyl, and q is 0 or 1, or benzophenone compound having the general formula: wherein R 13 is as defined above, R 14 is a substituted or unsubstituted, straight or branched C 2 -C 10 alkylene group, R 15 is hydrogen or hydroxyl, and R 16 is hydrogen, hydroxyl or a C 1 -C 6 alkoxy group, and (b-3) 10 to 94% by weight of other monomer copolymerizable therewith, not being vinyl monomer having an alkoxysilyl group or vinyl monomer having an organic UV-absorbing group and a vinyl polymerizable group in the molecule, and solvent, wherein 1 to 50 parts by weight of the surface-treated titanium oxide is present per 100 parts by weight of the vinyl copolymer. surface-treated titanium oxide comprising 100 parts by weight of core/shell type microparticles each consisting of a core of titanium oxide, optionally complexed with another inorganic oxide, and a shell of silicon oxide around the core, obtainable by treatment of said core/shell microparticles with 11 to 200 parts by weight of both surface treating component having the general formula and surface treating component having the general formula: R 1 Si(OR 2) 3 wherein R 1 is a C 1 -C 15 organic group which may have a (meth) acrylic moiety, and R 2 are C 1 -C 4 alkyl, (R 3 R 4 2 Si) 2 NH wherein R 3 are C 1 -C 15 organic group which may have a (meth) acrylic moiety, and R 4 are C 1 -C 6 alkyl, vinyl copolymer having alkoxysilyl and organic UV-absorbing groups attached on side chains and obtainable from copolymerization of (b-1) 1 to 50% by weight of vinyl monomer having an alkoxysilyl group, (b-2) 5 to 40% by weight of vinyl monomer having an organic UV-absorbing group and vinyl polymerizable group in the molecule, comprising benzotriazole compound having the general formula: wherein X is hydrogen or chlorine, R 11 is hydrogen, methyl, or a tertiary C 4 -C 8 alkyl group, R 12 is a straight or branched C 2 -C 10 alkylene group, R 13 is hydrogen or methyl, and q is 0 or 1, or benzophenone compound having the general formula: wherein R 13 is as defined above, R 14 is a substituted or unsubstituted, straight or branched C 2 -C 10 alkylene group, R 15 is hydrogen or hydroxyl, and R 16 is hydrogen, hydroxyl or a C 1 -C 6 alkoxy group, and (b-3) 10 to 94% by weight of other monomer copolymerizable therewith, not being vinyl monomer having an alkoxysilyl group or vinyl monomer having an organic UV-absorbing group and a vinyl polymerizable group in the molecule, and (b-1) 1 to 50% by weight of vinyl monomer having an alkoxysilyl group, (b-2) 5 to 40% by weight of vinyl monomer having an organic UV-absorbing group and vinyl polymerizable group in the molecule, comprising benzotriazole compound having the general formula: wherein X is hydrogen or chlorine, R 11 is hydrogen, methyl, or a tertiary C 4 -C 8 alkyl group, R 12 is a straight or branched C 2 -C 10 alkylene group, R 13 is hydrogen or methyl, and q is 0 or 1, or benzophenone compound having the general formula: wherein R 13 is as defined above, R 14 is a substituted or unsubstituted, straight or branched C 2 -C 10 alkylene group, R 15 is hydrogen or hydroxyl, and R 16 is hydrogen, hydroxyl or a C 1 -C 6 alkoxy group, and (b-3) 10 to 94% by weight of other monomer copolymerizable therewith, not being vinyl monomer having an alkoxysilyl group or vinyl monomer having an organic UV-absorbing group and a vinyl polymerizable group in the molecule, and solvent,