Polypropylene resin composition and formed article

A polypropylene resin composition comprising:

• (A) a propylene-based block copolymer satisfying requirements (a), (b), (c) and (d) defined below, and
• (B) from 0.01 to 1.0 part by weight, based on 100 parts by weight of (A), of aluminum hydroxy-di-(p-tert-butylbenzoate) particles having an average particle diameter, as measured by the laser diffraction method, of from 0.01 to 3 μm wherein particles having particle diameters of not less than 10 μm account for less than 5% by weight of all the particles of aluminum hydroxy-di-(p-tert-butylbenzoate);
• requirement (a):
• propylene-based block copolymer (A) is a propylene-based block copolymer including a polymer component (I) and a polymer component (II), wherein the polymer component (I) is a propylene polymer having an intrinsic viscosity as measured in Tetralin at 135° C., of from 0.1 to 5 dl/g and the polymer component (II) is a propylene polymer comprising propylene units and units of at least one comonomer selected from the group consisting of ethylene and α-olefins having 4-12 carbon atoms and having an intrinsic viscosity [η]II, as measured in Tetralin at 135° C., of from 1 to 20 dl/g,
• requirement (b):
• the polymer component (I) has an isotactic pentad fraction, as measured by 13C-NMR, of 0.98 or more,
• requirement (c):
• the content of the units derived from at least one comonomer selected from the group consisting of ethylene and α-olefins having 4-12 carbon atoms included in the polymer component (II) is from 1 to 80% by weight, provided that the overall amount of the polymer component (II) is 100% by weight, and
• requirement (d):
• the content of the polymer component (II) is from 1 to 70% by weight, provided that the weight of the propylene-based block copolymer (A) is 100% by weight,
• wherein the polymer component (I) is a propylene-based polymer component composed of from 0.01 to 30% by weight, based on the overall amount of the polymer component (I), of units derived from at least one comonomer selected from the group consisting of ethylene and α-olefin having 4-12 carbon atoms and units derived from propylene and the content of 20° C. xylene-soluble component in the polymer component (I) less than 1.0% by weight.