| 摘要 |
PURPOSE:To obtain a fine corrugated sheet or film without making use of a specific device, by receiving a resin compound treated by an aqueous medium without spreading a width substantially when the resin compound is made to discharge in a sheetlike or filmlike state from a mouth ring by making melt kneading of the same by an extruder. CONSTITUTION:At the time of preparation of a thermoplastic resin powder and granule coated with hydrophilic solid impalpable powder, the solid impalpable powder is sticked and laid in a state exposing on the surface. At least 1wt.pt. aqueous medium per 100wt.pt. porous conglomerate obtained by fusing partly such powder and granule each other is used so as to enable to secure foaming magnification of more than 3. A compound obtained by making mixing treatment of both by a mixer is molten and kneaded sufficiently under pressure terms wherein evaporation of the aqueous medium is controlled substantially within an extruder, and is discharged from a mouth ring in a sheetlike or filmlike state. In this instance, as it is received favorably without spreading its width, a foamed sheet or a film which is undulated finely and meeting at right angles with a receiving direction is obtained. |
