摘要 |
Provided is a novel composite sheet, including a substrate and a foamed layer which is provided on at least one surface side of the substrate, at a low cost in an environment-friendly manner, in which the composite sheet includes a foamed layer having a uniform fine-cell structure, the average pore diameter of each of spherical cells of the foamed layer can be precisely controlled to a small one, the control range of the density of the foamed layer is wide, the control range of the thickness of the foamed layer is wide, and the composite sheet can express an excellent mechanical strength and is preferably excellent in toughness and heat resistance. The composite sheet includes a substrate; and a foamed layer which is provided on at least one surface side of the substrate, in which: the foamed layer has spherical cells, an average pore diameter of each of the spherical cells being less than 30 µm; and the foamed layer has a density of 0.1 g/cm 3 to 0.9 g/cm 3 . |