| 摘要 |
PROBLEM TO BE SOLVED: To provide a polypropylene resin foamed sheet excellent in thermoforming properties, generating no large drawdown at a time of thermoforming, reduced in the lowering of melt tension(MT) caused by defoaming re-pelletization and good in recyclability. SOLUTION: The polypropylene resin foamed sheet is obtained by the extrusion foaming of a base material resin, which is based on a polypropylene resin and of which the equilibrium compliance (J0) in the measurement of dynamic viscoelasticity at 210 deg.C is 5.0×10-3-20.0×10-3 Pa-1 and the melt viscosity (<=) is 1.0×103-9.0×103 Pa.s, and has a density of 150-450 kg/m3 and a thickness of 0.5-2.0 mm. The dimensional change ratio of this sheet at a time of heating thereof at 180 deg.C for 3 min is -40 to -80% in an extrusion direction and 10 to -20% in a lateral direction. |
