| 摘要 |
PROBLEM TO BE SOLVED: To provide a plate-shaped foam manufacturing method that can manufacture a plate-shaped foam having a light property while suppressing continuous air bubbles.SOLUTION: A plate-shaped foam manufacturing method manufactures a cylindrical foam by push-foaming a polystyrene-based resin from a circular die together with a foaming agent, and after that, forms the plate-shaped foam by heat-fuisng the inside of the foam by sandwiching the foam by pinch roll. As the polystyrene-based resin, there is used the polystyrene-based resin in which a ratio (a/a) of an inclination (a) of a primary approximation straight line in a non-linear region in a logarithmic plot of a time-elongation viscosity curve which is acquired by measuring uniaxial elongation viscosity under the condition that a temperature is 160°C and a constant strain rate is 0.1/sec, and an inclination (a) of a primary approximation straight line in a lien region at the curve becomes not smaller than 1.2 and not larger than 2.0, thus manufacturing the plate-shaped foam whose density is 0.035g/cmto 0.065g/cm. |
