| 摘要 |
PURPOSE: To enhance the impact absorbing efficiency of a buffer material by filling a mold with highly prefoamed beads to heat them and highly compressing the foamed beads in a specific cracking ratio. CONSTITUTION: A front cover 3 is attached to the front of a main body 2 and ear covers 4 are attached to both side surfaces thereof and a buffer material 5 is attached to the inner periphery of the main body 2. The buffer material 5 is produced by a method wherein a mold is filled with polystyrene beads prefoamed to forming magnification of 50-60 times without exhausting the mold and the polystyrene beads are compressed in a cracking ratio of 1.2-2.2 while heated by steam and mutually fused to be molded. By this method, highly foamed molded object consisting of various shapes not spherical because of the collapse of beads is obtained. This beads foamed molded object consisting of cells having various shapes becomes large in histeresis loss in stress-strain relation and extremely high impact absorbability is obtained. |
