| 摘要 |
PURPOSE:To prevent ambient gas or water content in air from condensing by a method wherein condensation-proof devices are mounted through heat insulating parts with proper distances between the extrusion orifice at the tips of the lips of a die and the blowing-out parts at the tips of the throttled parts of the condensation-proof device. CONSTITUTION:A condensation-proof device 12, in which a heating part 11 is arranged near the efflux passage 5 of noncondensable gas equipped with a perforated part 2 to disperse the noncondensable gas, and a throttled part 3 to blow out the gas, is arranged through a heat insulating part 13 onto the lip 1 of an extruder die. On the other hand, a condensation-proof device 12', in which a heating part 11' is arranged near the efflux passage 5' of the noncondensable gas equipped with a perforated part 2' and a throttled part 3' is arranged through a heat insulating part 13' onto the lip 1'. Thus, no bad effects due to fluctuation and the like are given to an extruded film. In addition, safe operation is realized with explosive gas. Further, no ununiform temperature distribution develops in the extruder die. Furthermore, the deterioration of the film due to the condensation of condensable gas or the water content in air can be prevented from developing. |
