To obtain a propylene resin foamed laminated flat sheet excellent in rigidity, surface flatness, printing properties, appearance and cushioning properties though light in wt. and also excellent in drawing processability by cutting open a laminated and integrated cylindrical foamed object to form the same into a sheet and subsequently heat-treating the foamed object at specific temp. to take up the same by a roll.
A cylindrical foamed body wherein a surface layer comprising a propylene resin and having a density of above 0.4 g/m3 is provided on at least the single surface of a propylene resin foam layer is formed by extruding a foamable compsn. from a coextrusion die. Next, the cylindrical foamed body is cut open in an extrusion direction to form a foamed laminated sheet and both upper and rear surfaces of the foamed laminated sheet are heated to the (thermal deformation temp. -20°C) of the propylene resin constituting the surface layer 3 or higher and this heated laminated sheet is taken up to obtain a foamed laminated flat sheet 1 wherein the density of a core layer 2 is 0.045-0.30 g/cm3, the basis wt. of surface layers 3 is 20-300 g/m2, a whole density is 0.10-0.35 g/cm3 and a whole thickness is 2-10 mm.
MUROI TAKASHI
MOMOSE YOSHIAKI
