| 摘要 |
PROBLEM TO BE SOLVED: To provide a device constituted so that light (ultraviolet ray) reaches even the inside of the whole honeycomb and the partial dead space to the light is not generated with keeping high intensity of ultraviolet ray in a filter having a stereostructure such as a honeycomb state having the surface coated with titanium oxide or the like and large surface area, to enable to irradiate 2 planes of the filters with one light source and to enable to miniaturize the device. SOLUTION: A photocatalyst imparting structural body 2 and a light source 3 are alternately fitted to a rotary shaft 5 rotated by external power in an outer cylinder 1. The photocatalyst is irradiated with light having equal to or above necessary ultraviolet intensity for a time equal to or above several minutes by slowly rotating the rotary shaft 5. The whole contact surface is surely irradiated though a time lag is generated with the zones such as an upper or lower side, a left or right side or an immediate side or deepest side or the like in the honeycomb. The same effect in rotation is attained by fixing the rotary shaft 5 and rotating the light source. The photocatalyst after being irradiated with ultraviolet ray having equal to or above the necessary intensity once keeps the decomposition ability in 2-3 hr, though a little attenuation of the decomposition ability is observed. Then the irradiation once in several minutes does not cause the deterioration of the decomposition ability of the photocatalyst. |
