| 摘要 |
PROBLEM TO BE SOLVED: To provide a propylene resin-foamed laminated flat plate which has a high expanding rate, is used as a base stock of a box or the like, is lightweight and is excellent in processability. SOLUTION: The propylene resin-foamed laminated flat plate 1 is obtained by integrally layering a surface layer 3 consisting of an unstretched propylene resin film on both sides of a core layer 2 consisting of a propylene resin-extruded foam body by using a coextrusion foaming method. The propylene resin-extruded foam body constituting the core layer has 0.045-0.30 g/cm<SP>3</SP>density and≥50% closed cell ratio. The unstretched propylene resin film constituting the surface layer 3 has 60-300 g/m<SP>2</SP>basis weight. The density of the whole propylene resin-foamed laminated flat plate is 0.10-0.35 g/cm<SP>3</SP>. The propylene resin-foamed laminated flat plate satisfies expression (1): F≥2.5×10<SP>-3</SP>×Y-0.15 (wherein F (kgf) is the flexural strength of the propylene resin-foamed laminated flat plate, and Y (g/m<SP>2</SP>) is the basis weight of the propylene resin-foamed laminated flat plate). COPYRIGHT: (C)2009,JPO&INPIT
|
