摘要 |
PURPOSE:To improve the resistance for thermal shock and outer appearance by constituting the propylene block copolymer so as to fulfill the specific conditions, in a steering wheel which is made of the hard synthetic resin and whose core metal is covered by the propylent block copolymer. CONSTITUTION:As for a steering wheel, a core metal is made of the hard synthetic resin covered by propylene block copolymer. In this case, the above- described copolymer is constituted of the propylene homopolymer block and the random copolymer of propylene and ethylene, and the constituent ratio of the latter for the former is set within a range of 30/70-60/40 by weight. The content of ethylene in the above-described random copolymer block is set to 2-15wt%. Further, the melf flow rate (MFR) of the propylene block copolymer is set to 1-5g/10min. Therefore, a product having the sufficient resistance for thermal shock and the bright external appearance can be easily obtained. |