Patent ID: 9217067
Filing Date: 2015-12-22
Classification: B29C,B29K,C08J,C08K,C08L

Abstract:
1. A method for producing a polypropylene-based resin foamed blow-molded article, comprising extruding a foamable molten resin, obtained by kneading a polypropylene-based resin and a physical blowing agent, through a die to form a foamed parison in a softened state, placing the foamed parison between molds, and blow molding the foamed parison, wherein said polypropylene-based resin comprises a polypropylene-based resin (A) that meets requirements (1) to (3) shown below and a polypropylene-based resin (B) that meets requirement (4) shown below, when the polypropylene-based resins (A) and (B) are each subjected to dynamic viscoelasticity measurement in which an oscillation strain is applied thereto at a temperature of 190° C., and wherein a mixing ratio by weight (A:B) of the resin (A) to the resin (B) is 100:0.5 to 100:5, requirement (1): storage modulus G′ is less than 5.0×10 requirement (2): slope between two points [log G′ at log ω=0] and [log G′ at log ω=2] is 0.5 to 0.7, requirement (3): loss tangent (tan δ) at angular frequency (ω) of 1 rad/sec is 1.0 to 2.0, and requirement (4): loss tangent (tan δ) at angular frequency (ω) of 1 rad/sec is less than 1.0.