| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method for manufacturing parts for a regenerated synthetic resin slide fastener of good quality by using waste plastic generated from a manufacturing line for a synthetic resin slide fastener and waste products as raw materials. SOLUTION: In a manufacturing method, waste plastic 1 is pulverized by a rotating blade 14 rotating at high speed, and heated up to the temperature lower than the resin melting point by 20 deg.C or by the heat generated by the friction with the rotating blade, and the pulverized plastic in the high temperature state is extruded while being deaerated, and further extracted while being heated and melted, and granulated to manufacture primary pellets. The solid phase polymerization of the primary pellets thus formed is carried out in vacuum or in inactive gas atmosphere, and granulation is carried out to manufacture regenerated pellets of water content of 50 ppm or less and limiting viscosity of 0.65-0.8. The regenerated pellets are formed into the given shape of a slide fastener. Preferably plastic heated and melted in the primary pellet manufacturing process is filtered to remove foreign matters.</p> |
