| 摘要 |
<p>PURPOSE:To make machining of a mold simpler and to provide ease of releasing a molded sole from the mold even though the molded sole has acetabulum projections of undercut shape, by a method wherein a particular foam molding material for soles is introduced into a cavity of the sole mold with external walls having a particular tilting angle against the bottom surface, and crosslinking molding is carried out. CONSTITUTION:The tilting angle alpha of an external wall 111 of recessed part of a round acetabulum projection is limited to 100-120 deg.. If the tilting angle alpha is less than that, a considerable labor is required to release a molded sole from a mold, and it becomes hard to form the undercut shape by foaming. And, if it is larger than that, the thickness of a base 201 of the molded acetabulum projection becomes too thick in comparison with a tip 202, causing a decrease in the sucking and cushioning characteristics. The expansion ratio of foam molding material for soles is limited to 1.3-1.8 times. If the expansion ratio is less than that, the molded sole becomes heavy causing a decrease in the cushioning characteristic, and it becomes hard to form the undercut shape by foaming. And if it is larger than that, the durability of the foam molded sole is diminished.</p> |
