Patent ID: 7641940

Claim:
A method for applying a photocatalytic coating to a thermoplastic surface, comprising the steps of: a) wetting one surface side of a thermoplastic sheet of thermoplastic polyolefin (TPO) with a solvent; b1) separately forming wetted particles from a photocatalyst comprising at least one of TiO.sub.n1 and WO.sub.n2, wherein 0<n1<2, and 0<n2<3, the wetted particles having sizes of 0.1 mm to 0.25 mm: b2) applying the wetted particles to the wet thermoplastic surface in an evenly distributed layer having a uniform coating in a range between approximately 1.5 mg/cm 2 to approximately 2.5 mg/cm 2 on the wetted one side of the thermoplastic surface; c) heating the surface of a pressing means to a temperature within a range of approximately 80° C. to approximately 130° C.; d) contacting the photocatalyst-coated thermoplastic sheet with the heated pressing means; e) applying a mild pressure within a range of approximately 24 psi to approximately 36 psi with the heated pressing means to imbed the photocatalyst into the surface of the thermoplastic sheet until bonding occurs between the photocatalyst and the thermoplastic surface; f) removing the thermoplastic sheet bonded with photocatalyst from the pressing means; and g) cooling the product from step f) thereby providing a structural surface that is resistant to the growth of damaging algae, fungus, bacteria, mold and mildew.