Patent ID: 7169338

Claim:
A method for manufacturing a foam-molded article by molding between molds a parison with a foam layer formed by extruding an expandable molten resin composition, obtained by melt-kneading a polyethylene resin and a physical foaming agent, to an area of low pressure from a die, wherein the polyethylene resin is selected from at least one of the following I), II), and III), and wherein the apparent density of the foam layer in the foam-molded article is about 0.04 to 0.3 g/cm 3 ; I) a resin comprising 40 to 85 wt % polyethylene (A) with a density that is more than 0.94 g/cm3 and not more than 0.97 g/cm3, and a melt flow rate of 0.1 to 20 g/10 minutes; and 15 to 60 wt % polyethylene (B) with a density of 0.89 to 0.94 g/cm3, a melt flow rate of 0.2 to 20 g/10 minutes, and a melt tension of not less than 2 cN (provided that the total of polyethylene (A) and (B) is 100 wt %), II) a resin which has at least one endothermic peak having a top temperature of not less than 125° C. on a DSC curve obtained by differential scanning calorimetry, and in which the ratio of the heat quantity of the endothermic peak(s) at not less than 125° C. with respect to the total heat quantity of the endothermic peak(s) is 50 to 95%. melt flow rate is 0.2 to 25 g/10 minutes, and melt tension is not less than 1.5 cN. III) a resin which comprises 40 to 85 wt % polyethylene (A) having a density more than 0.94 g/cm3 and not more than 0.97 g/cm3, and a melt flow rate of 0.1 to 20 g/10 minutes; and 15 to 60 wt % polyethylene (B) having a density of 0.89 to 0.94 g/cm3, a melt flow rate of 0.2 to 20 g/10 minutes, and a melt tension of not less than 2 cN (provided that the total of polyethylene (A) and (B) is 100 wt %); which has at least one endothermic peak having a top temperature of not less than 125° C. on a DSC curve obtained by differential scanning calorimetry; and in which the ratio of the heat quantity of the endothermic peak(s) at not less than 125° C. with respect to the total heat quantity of the endothermic peak(s) is 50 to 95%, melt flow rate is 0.2 to 25 g/10 minutes, and melt tension is not less than 1.5 cN.