Uniformly dispersible photocatalyst coating liquid, method for producing the same, and photocatalytically active composite material obtained using the same

摘要

Disclosed is a uniformly-dispersed photocatalyst coating liquid having excellent dispersion stability of titanium oxide particles which have photocatalytic activity, which coating liquid places no burden on the environment while being excellent in handling properties. In addition, this uniformly-dispersed photocatalyst coating liquid enables to form a photocatalyst coating film, which is excellent in photocatalytic activities (antifouling property and/or antibacterial property), transparency and durability, on the surface of a base when applied thereto. Also disclosed are a method for producing such a uniformly-dispersed photocatalyst coating liquid, and a photocatalytically active composite material obtained by using such a uniformly- dispersed photocatalyst coating liquid. Specifically disclosed is a uniformly-dispersed photocatalyst coating liquid which is a composition containing, in an aqueous solvent, titanium oxide dispersed particles having an average primary particle diameter of 5-50 nm and an average dispersed particle diameter of 10-100 nm, a polymer dispersing agent, an alkoxysilane hydrolysis-polycondensation product, an organic amine, and additionally if necessary, silver particles. The uniformly-dispersed photocatalyst coating liquid has a pH within a range of 5-9. Also specifically disclosed are a method for producing such a uniformly-dispersed photocatalyst coating liquid, and a photocatalytically active composite material having antifouling property and antibacterial property, which is obtained by applying such a uniformly-dispersed photocatalyst coating liquid over the surface of a base.