Photocatalyst composite and process for producing the same

A process is described for removing deleterious materials, malodorous materials, oily components, bacteria, actinomyces, fungi, algae or the like, or preventing the adsorption of algae, dust or contaminants, which comprises using a photocatalytic composite prepared by providing on a substrate a first layer containing a less degradative adhesive and free of photocatalyst particles by coating or spraying the less degradative adhesive onto the substrate and then providing a second layer comprising a mixture of the less degradative adhesive and photocatalyst particles on the first layer, the amount of the photocatalyst particles being 5 to 98% by volume of the total amount of the photocatalyst particles and the less degradative adhesive of the second layer; and applying a ray having a wavelength of not less than the band gap energy of the photocatalyst particles onto the photocatalytic composite.