To provide a retroreflector having retroreflective properties and capable of retaining the properties without particularly requiring maintenance because pollutants are readily removed by a rainfall, etc.
In the retroreflector having retroreflective properties, light is incident and recurrent from parts of retroreflective spherical beads not embedded in a substrate and pollutants are readily washed off by a rainfall, etc., because a photocatalyst-containing layer formed on each of at least the parts of the beads not embedded in the substrate is activated with UV and made hydrophilic and a water membrane is formed between the photocatalyst- containing layer and the pollutants. The pollutants are more readily washed off because the activated photocatalyst degrades lipophilic components contained in the pollutants.
HARADA ATSUSHI