Coating composition for producing photocatalytically active layer for cleaning air and water, comprises mixture of nanocrystalline titanium dioxide material and sol of photocatalytically active metal oxide

摘要

The coating composition comprises an additive of a non photo-catalytically active material and, a mixture of nanocrystalline titanium dioxide material and sol of a photo-catalytically active metal oxide, in which the metal oxide is in amorphous state. 20-70 wt.% of the nanocrystalline titanium dioxide material is provided out of the total content of solid. The sol of photo-catalytically active metal oxide contains titanium dioxide, zinc oxide, zirconium dioxide or tin oxide. An independent claim is also included for a method for producing a photo-catalytically active layer, which involves: (A) manufacturing a homogeneous liquid mixture from the nanocrystalline titanium dioxide powder and sol of photo-catalytically active metal oxide; (B) applying the liquid mixture on surface; (C) drying developing layer; and (D) subjecting the coated surface to heat treatment.