PURPOSE: To improve weatherability and barrier properties of water or light by applying a finish coating material prepared by compounding a specific amount of pigment or aggregate with a fluorine-containing copolymer aqueous dispersion to the undercoating material applied to a base material.
CONSTITUTION: Topcoating is prepared by compounding pigment and/or aggregate with a fluorine-containing copolymer aqueous dispersion in a ratio of 10-1000 pts.wt. per 100 pts.wt. of a fluorine-containing copolymer. An undercoating material is applied to a base material and the topcoating prepared as mentioned above is applied to the formed film to perform coating finish. As fluoroolefin suitable in the fluorine-containing copolymer, there are tetrafluoroethylene and chlorotrifluoroethylene. The aforementioned topcoating can be applied thickly and a dense film can be formed and, therefore, excellent weatherability and barrier properties of water or light are developed.