| 摘要 |
PROBLEM TO BE SOLVED: To provide polypropylene-based resin pre-foamed pellets which are obtained by an extrusion-foaming method of an inexpensive production process, have a good balance between a fusing property and a low contraction property, when molded in an internal mold, and can be molded in thick shapes, and to provide a polypropylene-based internal mold foamed molded article obtained from the polypropylene-based resin pre-foamed pellets. SOLUTION: The polypropylene-based resin is obtained by feeding a base material resin comprising the polypropylene-based resin and a foaming agent into an extruder, kneading and cooling the mixture, extruding the mixture into a low pressure area through a small hole die, and then finely pelletizing the extruded product. The half value width of the melting point peak is ≥20°C, when the crystal melting of the polypropylene-based resin pre-foamed pellets is measured by a differential scanning calorimeter method. COPYRIGHT: (C)2010,JPO&INPIT |
