| 摘要 |
PURPOSE:To obtain the title foam improved in productivity, stability of quality, appearance, and surface smoothness by irradiating the surface layer of a sheet containing a specified polyolefin resin and a thermally decomposable blowing agent with a low-voltage ionizing radiation and foaming the surface by heating. CONSTITUTION:A polyolefin resin graft- or co-polymerized with a silicon compound which is hydrolyzable and condensible through dehydration is mixed and kneaded with a thermally decomposable blowing agent to obtain a foamable resin composition. This composition is molded into a sheet. Both surface layers of this sheet are irradiated with an ionizing radiation at a voltage as low as 50-300Kev, desirably 100-250KeV to crosslink only the surface layers of the sheet, and the surfaces are foamed by heating to obtain the title foam. |
