Abstract: A resin composition for a component of an air intake system of an internal combustion engine including the following components (1), (2), and (3): [Components] (1) polypropylene-based resin: 67 to 89 wt % (2) acid-modified polypropylene-based resin: 1 to 3 wt % (3) carbon fiber and graphite powder: 10 to 30 wt %, the relationship between the thickness and the resonance frequency of a test specimen formed of the resin composition satisfying the following expression: [Relationship between thickness and resonance frequency]resonance frequency (Hz)?(98.5×thickness (mm))+15.

Abstract: A resin composition for a component of an air intake system of an internal combustion engine including the following components (1), (2), and (3): [Components] (1) polypropylene-based resin: 67 to 89 wt % (2) acid-modified polypropylene-based resin: 1 to 3 wt % (3) carbon fiber and graphite powder: 10 to 30 wt %, the relationship between the thickness and the resonance frequency of a test specimen formed of the resin composition satisfying the following expression: [Relationship between thickness and resonance frequency]resonance frequency (Hz)?(98.5×thickness (mm))+15.

Abstract: A fuel cell member-forming resin composition including (1) 67 to 89 wt % of a polypropylene-based resin, (2) 1 to 3 wt % of an acid-modified polypropylene-based resin, and (3) 10 to 30 wt % of carbon fibers and a high-purity ultrathin graphite powder having an ash content of less than 0.5 wt %.

Abstract: Blow-molding molds 10 and 20 having parison shutters 31 and 32 for preventing an inflation of the parison 3 toward the outside of the molds 10 and 20 are used in a blow-molding method of the present invention. In other words, a closed space for preventing the parison 3 from inflating out of the molds 10 and 20 are formed by the parison shutters 31 and 32 and a predetermined air is secured in the parison 3 in a frame clamping step (B). In the subsequent mold clamping step (C), the pressure inside the parison 3 starts to be increased when the molds 10 and 20 press the parison 3, so that the parison 3 can be continuously in contact with the die design surface 11. Accordingly, since the parison 3 can be uniformly contracted by cooling, molding failure such as streaks and uneven pattern transfer can be avoided, thus obtaining a blow-molded product having good appearance.