| 摘要 |
PROBLEM TO BE SOLVED: To attain both the photocatalyst action by a photocatalyst film and an increase in coating strength to an airtight vessel by arranging an ultraviolet ray transmissive photocatalyst film with which an outside surface of the airtight vessel is coated and in which recesses-projections are formed on an outside surface. SOLUTION: A large number of recessed-projections are formed on the almost whole outside surface of a discharge space part 2a by frost work, and since a photocatalyst film 10 having a prescribed thickness is formed on the almost whole outside surface of a frost work surface, a large number of recessed-projections are also formed on an outside surface of the photocatalyst film 10 in response to a large number of recessed-projections of the frost work surface. Prescribed voltage is impressed on a pair of electrodes 3a and 3b of an ultraviolet lamp 1, and when discharge is generated in a space part 2a of a bulb 2, mercury in the space part 2a is excited, and ultraviolet rays of a prescribed wave length area are applied to the photocatalyst film 10 from the frost work surface, and are radiated outside. In this way, since the photocatalyst action can be practiced by reliably irradiating to the photocatalyst film 10 with the ultraviolet rays, a photocatalyst acting effect is increased, and coating strength of the photocatalyst film 10 to an airtight vessel outside surface can also be increased. |
