| 摘要 |
PURPOSE:To relieve the neck-in during molding, prevent the generation of strain and local crystallization in a molded part from developing and consequently contrive to improve the mechanical strengths and quality of the molded part by a method wherein molten resin in extruded directly in a high temperature zone suitable for extrusion and, then passed through a low temperature zone in order to shape the resin. CONSTITUTION:A high temperature zone 7 suitable for extrusion and a low temperature zone 8 suitable for cooling the set in advance in a liquid. Polymeric material to be extruded is extruded from an extruder die 2, which is immersed in the high temperature zone 7, and then consecutively introduced in the low temperature zone 8 so as to be left through cooling rolls 3 and a guide roll 4 from the liquid in order to be taken up through a take-up roll 5 in the form of the coil of a molded product 6. By this method, the neck-in during the forming of a sheet is relieved and the strain and sectional ununiformity of a molded part are prevented from developing and consequently the molded part improved in mechanical strength, quality and the like is provided. |
