FINE PORE THERMOPLASTIC RESIN FOAM CONTAINING METALLIC OXIDE

摘要

An object of the present invention is to provide a thermoplastic resin sheet which has both high reflectance ratio and excellent shape-holding property suitable for backlights and illumination boxes for use in illumination signboards, illumination fixtures and displays and illumination boxes. The thermoplastic resin foam is manufactured by a manufacturing method comprising a process for containing inert gas by holding thermoplastic resin sheet containing metallic oxide in a pressurized inert gas atmosphere and a process for heating the thermoplastic resin sheet in which the inert gas is contained at a temperature higher than the softening temperature of the thermoplastic resin, under normal pressure, and foaming the resin.