| 摘要 |
PURPOSE:To produce an expanded polyolefin molding of a high expansion ratio. CONSTITUTION:A process for extrusion-foaming a polyolefin resin, wherein a mixture of methanol or ethanol with at least one compound selected from the group consisting of diethyl ether, vinyl ethyl ether, acetone, n-pentane and isopentane is used as a blowing agent. Since the blowing agent is liquid, it can be supplied at high accuracy. A high-speed signal transmission cable provided with a highly expanded insulation layer of a degree of expansion of 75% or above can be produced in a nonpolluting manner. |
