PHOTOCATALYST COMPOSITION, PHOTOCATALYST COATING FILM AND PHOTOCATALYST COATING PRODUCT

PROBLEM TO BE SOLVED: To provide a photocatalyst composition satisfying excellent long term retention property of algae-proofing properties, weather resistance and low damage properties to a photocatalyst undercoat film at the same time, a photocatalyst coating film and a photocatalyst coating product.SOLUTION: There is provided a photocatalyst composition in which a non-antibacterial inorganic compound (AA) contains a photocatalyst inert inorganic compound (A2) and a photocatalyst active inorganic compound (B), a mass ratio of the antibacterial metal compound (A1) to the photocatalyst inert inorganic compound (A2) (A1/A2) is 0.001 to 0.25, and the photocatalyst active inorganic compound (B) satisfies following (i) condition or both of (i) and (ii) conditions. (i) an amount of hydrogen peroxide generated when a suspension containing the photocatalyst active inorganic compound (B) is irradiated with an ultraviolet ray with wavelength of 380 nm or less and intensity of 5 mW/cmfor 60 sec., is 80 μM or less. (ii) an amount of hydroxy radical ([.OH]) generated when the suspension containing the photocatalyst active inorganic compound (B) is irradiated with the ultraviolet ray for 60 seconds, is 1.0 μM or less.SELECTED DRAWING: None 【課題】防藻性の優れた長期持続性と耐候性、光触媒直下塗膜に対する低損傷性とを同時に満たす光触媒組成物、光触媒塗膜及び光触媒塗装製品の提供。【解決手段】非抗菌性無機化合物（ＡＡ）が、光触媒不活性無機化合物（Ａ２）と、光触媒活性無機化合物（Ｂ）とを含み、抗菌性金属化合物（Ａ１）の光触媒不活性無機化合物（Ａ２）に対する質量比（Ａ１／Ａ２）が、０．００１〜０．２５であり、光触媒活性無機化合物（Ｂ）が、以下の（ｉ）、若しくは以下の（ｉ）、（ii）両方の条件を満たす光触媒組成物。（ｉ）前記光触媒活性無機化合物（Ｂ）を含む懸濁液に、波長３８０ｎｍ以下、強度５ｍＷ／ｃｍ2の紫外光を６０秒間照射した際に発生する過酸化水素量が、８０μＭ以下である（ii）前記光触媒活性無機化合物（Ｂ）を含む懸濁液に、同紫外光を６０秒間照射した際に発生するヒドロキシラジカル量[・ＯＨ]が、１．０μＭ以下である：【選択図】なし