| 摘要 |
PROBLEM TO BE SOLVED: To provide a lamp cover for protecting a lighting lamp in which it prevents blackish and nonuniform decoloring and extremely improves light transmissivity against emitted light from a light source and even after stopping of the emitting light from the light source, the light emitting by its afterglow can be continued.SOLUTION: A lamp cover 1 is composed of a molded member of polycarbonate resin including at least luminous fluorescent body generating long persistence fluorescent light and light diffusion agent and a reduction rate of illumination intensity when a lamp cover with a thickness of 0.8 mm is used is less than 20% when it is not used. This lamp cover is manufactured by the process of manufacture including the steps for mixing pellet of PC resin containing light diffusion agent and luminous fluorescent body under co-existence of oil, extrusion molding them at a cylinder temperature of 235 to 250°C to get pellet-like PC resin compound, and injection molding the PC resin compound got by the former step at a cylinder temperature of 235 to 260°C or injection molding it at 240 to 280°C.SELECTED DRAWING: Figure 1 |
