An antireflective coating having improved alkali resistance is formed on a transparent substrate of synthetic resin as an outermost layer and has a three-dimensional crosslinked structure containing F and Si atoms. The crosslinked structure is composed of Si--O--Si and Si--C.sub.2H.sub.4--(CF.sub.2).sub.n--C.sub.2H.sub.4--Si linkages wherein n is 4 or 6; the molar ratio of F atoms to Si atoms is from 8.0 to 10.0; and perfluoroalkyl groups account for 90 to 100 mol % of all monovalent organic substituent groups attached to silicon atoms. The antireflective coating can exhibit such alkali resistance that when a droplet of a 1 wt % NaOH aqueous solution is rested on the antireflective coating for 30 minutes and then wiped off, the appearance of the coating is kept unchanged from the initial appearance.