A high-refractive-index hardcoat layer of a sufficiently reduced haze value can be obtained from an aqueous composition containing Si, Al and at least one of Ti and Zr, in which the ratio of the number of atoms of Ti and Zr with respect to the number of atoms of Si is 2.5 to 18, the ratio of the number of atoms of Al with respect to the number of atoms of Si is 0.08 to 0.22, and the aqueous composition has a haze value of 0.5% or less.