| 摘要 |
PURPOSE:To newly impart high rigidity, printability, beautifulness or the like while holding conventional characteristics, in a thermoplastic resin foamed sheet of which the foaming magnification is specific times or more and the density is a specific value or less, by differentiating the foaming state on one surface side of the sheet from that on the other surfaces side thereof. CONSTITUTION:A heterogenous foamed sheet S is characterized by that foaming magnification is 1.1 times or more and density is 0.8 or less and the foaming magnification on one surface side B of the sheet S is high while that on the other surface side A of the sheet is low or substantially zero. A foamed state is coarse on one surface side B of the sheet S and successively becomes dense toward the other surface side B thereof. By this constitution, the sheet S holds conventional characteristics such as lightweight properties, heat insulating properties or buffering properties on one surface side B thereof and can satisfy various physical properties such as rigidity, printability or beautifulness on the other surface side A thereof. |
