Patent ID: 7582696

Claim:
A process to prepare a pelletized or molded article of a polypropylene-based resin composition comprising the following steps: combining in a melt-kneading device; component (A): propylene homopolymer having an MFR of 10 g/10 minutes or more and isotactic pentad fraction of 98.0% or more, and/or propylene block copolymer having an MFR of 30 g/10 minutes or more and composed of a propylene homopolymer portion and copolymer portion of propylene and another α-olefin, the propylene homopolymer portion having an isotactic pentad fraction of 98% or more, and the copolymer portion containing propylene at 30 to 85% by weight and having a weight-average molecular weight of 400,000 or more: 10% by weight or more but less than 89% by weight, component (B): at least one species of inorganic filler selected from the group consisting of talc, calcium carbonate, natural mica, synthetic mica, wollastonite and montmorillonite, having an average particle size of 10 μm or less, determined by laser diffractometry: more than 0% by weight but 30% by weight or less, and component (D): ethylene- and/or styrene-based elastomers having an MFR of 0.1 to 20 g/10 minutes and density of 0.850 to 0.910 g/cm 3 : 5 to 50% by weight; performing melt-kneading device of components (A), (B) and (D); adding component (C): carbon fibers having a fiber diameter of 2 to 15 μm and fiber length of 1 to 20 mm: 4 to 20% by weight through a side feeder of the melt-kneader to disperse the carbon fibers and maintain an average length of 0.05 mm or more but less than 0.09 mm; and extruding the resulting polypropylene-based resin composition in pellets or molded shape.