| 摘要 |
PROBLEM TO BE SOLVED: To maintain water repellency for a long period and control a spread of contamination for a cover surface by forming virtually a transparent surface layer that contains photo catalyst particles, water repellent silicone and a substance to prevent water repellent silicone from having a hydrophilic property by means of the light excitation of the photo catalyst. SOLUTION: A lighting system 10 for a tunnel as a recessed type has a housing to be buried in the concrete wall of the tunnel. A light source 16 covered with a cover glass 18 is applicable to a high pressure sodium vapor lamp, low pressure sodium vapor lamp, metal halide lamp, fluorescent lamp, mercury vapor lamp, etc. The surface layer that contains photo catalyst particles, silicone, and cobalt or cobalt compound or the like which is the substance to prevent the silicone from having a hydrophilic property by the photo excitation of the photo catalyst is formed on the external surface of the cover glass 18. The layer that has the photo catalyst particles and water repellent silicone is formed on the surface of the cover glass 18 and the substance to prevent the silicone from having the hydrophile property is fixed in at least a part of the surface layer. |
