| 摘要 |
PROBLEM TO BE SOLVED: To obtain a flat foamed sheet by a method wherein when a sheet having a specific average foam diameter, density, and thickness, and a wide area surface of at least a specific value is placed on a standard plane, a maximum distance therefrom to the surface is set to at most a specific value. SOLUTION: Cooling rolls 11, 12, 13, 14 are placed so that their upper ends form a horizontal one plane. Heat rolls 1, 2 heat a foam sheet X, which is supported from both faces by cooling rolls 11, 12, 13, 14 to hold in a horizontal straight plane, and stretched between the heat roll 1 and the take-up rolls 21, 22. Thereafter, it is cut into flat sheets. Herein, the foam sheet X has an average foam diameter of 0.05-2 mm, a density of 0.04-0.9 g/cc, a thickness of 0.3-15 mm, and a surface of 5000 cm<2> or more. Furthermore, when it is positioned on a standard plane, the maximum distance in the wide surface spaced from the standard plane is set to be 2% or lower of the maximum straight line of the foamed sheet X. |
