| 摘要 |
PURPOSE:To obtain the titled molded article having luster and a smooth surface free of dents between each of particles by a method wherein expandable spherical particles having specified properties are prepared, and after compressing and filling in a mold, the particles are expanded by heating. CONSTITUTION:The expandable particles of a cross-linked polystyrene resin are prepared such that the surface smoothness S of is not higher than 1.05, the expansion ratio D is about 20-40 and the damping coefficient T of the pressure of air forced in the particles is in the range of D/1,500>=T>=D/2,500. In order to further increase the expanding capability of the particles which have an expanding capability of 1.3 times, the particles are compressed to 95-50% of the original bulk volume of the particles (compression ratio being 5-50%). Then, the compressed particles are filled in a mold, and are expanded by heating in such a manner that the increased expanding capability is not lowered. |
