A coating composition comprising: an component and a component, wherein the component is at least one silicon-containing substance selected from the group consisting of organic silicon compounds of General Formula: (R 1) a (R 3) b Si(OR 2) 4-(a+b) where each of R 1 and R 3 is a C 1-10 alkyl group, aryl group, halogenated alkyl group, halogenated aryl group, or alkenyl group, or an organic group having an epoxy group, an acryloyl group, a methacryloyl group, a mercapto group, a ureido group, an amino group, or a cyano group and is bonded to a silicon atom through a Si-C bond; each of R 2 is a C 1-8 alkyl group, alkoxyalkyl group, or acyl group; and each of a and b is an integer of 0, 1, or 2; and a + b is an integer of 0, 1, or 2; and General Formula: [(R 4) c Si 3-c] 2 Y where R 4 is a C 1-5 alkyl group, each X is a C 1-4 alkyl group or acyl group; Y is a methylene group or a C 2-20 alkylene group; and c is an integer of 0 or 1 and a hydrolyzed compound of the organic silicon compounds; the component is colloidal particles formed by bonding an organic silicon compound having a ureido group to surfaces of modified metal oxide colloidal particles having a primary particle diameter of 3 nm to 100 nm formed by providing metal oxide colloidal particles having a primary particle diameter of 2 nm to 60 nm as nucleuses and partially or fully coating the surfaces of the colloidal particles with a coating material made of acidic oxide colloidal particles having a primary particle diameter of 1 nm to 4 nm; the metal oxide colloidal particles are at least one metal oxide selected from the group consisting of Ti, Fe, Cu, Zn, Y, Zr, Nb, Mo, In, Sn, Sb, Ta, W, Pb, Bi, and Ce; and the coating material is colloidal particles of at least one metal oxide selected from the group consisting of Si, Sn, Mo, Sb, and W. an component and a component, wherein the component is at least one silicon-containing substance selected from the group consisting of organic silicon compounds of General Formula: (R 1) a (R 3) b Si(OR 2) 4-(a+b) where each of R 1 and R 3 is a C 1-10 alkyl group, aryl group, halogenated alkyl group, halogenated aryl group, or alkenyl group, or an organic group having an epoxy group, an acryloyl group, a methacryloyl group, a mercapto group, a ureido group, an amino group, or a cyano group and is bonded to a silicon atom through a Si-C bond; each of R 2 is a C 1-8 alkyl group, alkoxyalkyl group, or acyl group; and each of a and b is an integer of 0, 1, or 2; and a + b is an integer of 0, 1, or 2; and General Formula: [(R 4) c Si 3-c] 2 Y where R 4 is a C 1-5 alkyl group, each X is a C 1-4 alkyl group or acyl group; Y is a methylene group or a C 2-20 alkylene group; and c is an integer of 0 or 1 and a hydrolyzed compound of the organic silicon compounds; the component is colloidal particles formed by bonding an organic silicon compound having a ureido group to surfaces of modified metal oxide colloidal particles having a primary particle diameter of 3 nm to 100 nm formed by providing metal oxide colloidal particles having a primary particle diameter of 2 nm to 60 nm as nucleuses and partially or fully coating the surfaces of the colloidal particles with a coating material made of acidic oxide colloidal particles having a primary particle diameter of 1 nm to 4 nm; the metal oxide colloidal particles are at least one metal oxide selected from the group consisting of Ti, Fe, Cu, Zn, Y, Zr, Nb, Mo, In, Sn, Sb, Ta, W, Pb, Bi, and Ce; and the coating material is colloidal particles of at least one metal oxide selected from the group consisting of Si, Sn, Mo, Sb, and W.