| 摘要 |
PURPOSE:To heat a film with good efficiency by preventing the dispersion of infrared rays by attaching a light directing slit to the tip of a focusing type infrared heater for longitudinal stretching method. CONSTITUTION:In the longitudinal stretching of a film by using a preheating roller 8, a low-speed stretching roller 9 and a high-speed stretching roller 10, light-directing slits 12 in which aluminium or gold-plated flat mirrors are set in a mutually facig manner are set at the tip of a focusing type infrared heater 11, and running film 7 is heated by infrared rays. Infrared rays focussed by the heater 11 pass through the slits 12 and heat the film 7 with good efficiency. Therefore, high-speed operations are made possible. Optical fibers may be used instead of the light-directing slits. |
