| 摘要 |
PROBLEM TO BE SOLVED: To mold a molding of a thick large size of high quality or a complicated shape in which a thick part and a thin part coexist from non-crosslinked polyolefin prefoamed particles. SOLUTION: The method for manufacturing a foam molding in polyolefin resin mold comprises the steps of preheating prefoamed particles in the mold for a time of 12 sec or less from a start of supplying steam by press rising it to a steam pressure (kg/cm<2> G) in the mold of a range of 20 to 60% of the steam pressure (kg/cm<2> G) in the mold within 3sec at the time of primarily heating (heating both the surfaces), then raising the pressures (kg/cm<2> G) in both the molds to a saturated steam pressure (kg/cm<2> G) corresponding to a temperature of a range of -5 to +5 deg.C of a melting point of a base material resin of the particles within 3sec, and primarily heating it for a time of 6 sec or less, thereby foaming the particles and fusion bonding among the particles. |
