| 摘要 |
PROBLEM TO BE SOLVED: To obtain a composition that gives a molded article excellent in surface hardness particularly under a dynamic load, such as pencil scratch hardness, i.e., marring resistance, by incorporating a specified amount of pyrophylite into a polyolefin. SOLUTION: This composition is obtained by incorporating a natural clay mineral comprising pyrophylite [having a constitutional formula Al2 Si4 O10 (OH)2 ] having a mean particle diameter of about 0.1-15μm, in an amount of at most 80 wt.% based on the composition, into a polyolefin. The polyolefin used preferably comprises a polypropylene resin, preferably comprising a propylene block copolymer which consists of a highly crystalline polypropylene component (crystalline component) and an ethylene/propylene copolymer rubber component (rubber component). It is desirable that the propylene block copolymer has a melt flow rate (ASTM D1238, at 230 deg.C, under a load of 2.16 kg) of 1-400 g/10 min and contains 5-50 wt.% (rubber component soluble in n-decane at ordinary temperature. |
