| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing polyolefin-based resin foam particles having a high expansion ratio and excellent mold filling properties. SOLUTION: The method for producing polyolefin-based resin foam particles with an expansion ratio of 20 or more includes steps of dispersing a polyolefin-based resin particle in a water-based dispersion medium in a pressure vessel, adding an inorganic gas, heating and pressurizing to a temperature not less than the softening temperature of the polyolefin-based resin particle to impregnate the polyolefin-based resin particle with a foaming agent, and releasing the polyolefin-based resin particle impregnated with the foaming agent into a region of pressures below the inner pressure of the pressure vessel. In the method, the polyolefin-based resin particle contains the following components (A) and (B); (A) a glycerin ester with a 6C-30C fatty acid, and (B) a hydrophilic substance with a molecular weight of at most 600 making the percentage of the moisture content of a foam particle at least 0.7 wt.% when the foam particle is produced using nitrogen gas as an inorganic gas. COPYRIGHT: (C)2010,JPO&INPIT
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