Abstract: A propylene resin composition having excellent physical property balance (heat resistance and impact strength at low temperature), and excellent injection molding processability as well as excellent paintability is provided, which propylene resin composition comprises component (a): a propylene-ethylene block copolymer comprising 85-95% by weight of a crystalline polypropylene homopolymer portion (unit A) and 5-15% by weight of an ethylene-propylene random copolymer portion (unit B) having an ethylene content of 30-60% by weight, the melt flow rate of the total component (a) being 50-500 g/10 min in an amount of 100 parts by weight, component (b): talc having an average particle diameter of 1.5-10 .mu.m and an average aspect ratio of 4 or more in an amount of 10-60 parts by weight, and component (c): an ethylene-1-octene copolymer comprising 20-50% by weight of 1-octene, and having a density of 0.86-0.89 g/cm.sup.3 and a tensile strength at break of 10 MPa or more in an amount of 10-60 parts by weight.

Abstract: A propylene resin composition containing talc, comprising the following components (a), (b) and (c) is provided: (a) 100 parts by weight of a propylene/ethylene block copolymer containing a crystalline propylene homopolymer part (Unit A part) and an ethylene/propylene random copolymer part (Unit B part); (b) 0.1 to 80 parts by weight of talc having an average particle size of 1.5 to 20 microns and an average aspect ratio of not less than 4; and (c) 2 to 80 parts by weight of an ethylene/.alpha.-olefin copolymer polymerized by using a metallocene catalyst, and containing an .alpha.-olefin having 3 to 16 carbon atoms. This composition has good paintability, molding processability (fluidity) and excellent mechanical strength balance, and is useful for a material for e.g., automobile parts.

Abstract: There is provided a heat-resistant, propylene resin-based molding material, comprising the following components (A) and (B):component (A): 3 to 97% by weight of a resin-impregnated glass fiber bundle comprising:constituent (a.sup.1): 20 to 80 parts by weight of glass fibers having a length of at least 3 mm and an average diameter of 20 .mu.m or less, andconstituent (a.sup.2): 80 to 20 parts by weight of a crystalline propylene polymer at least partly modified with an unsaturated carboxylic acid or a derivative thereof, the MFR of the modified polymer being 50 g/10 min or more, in which the glass fibers are present in the constituent (a.sup.2) in such a state that they are arranged almost in parallel with one another; andcomponent (B): 97 to 3% by weight of a crystalline propylene polymer having an MFR of 50 g/10 min or more.

Abstract: A process for producing a molded product of propylene resin which includes melting and kneading at least a part of the following component (a), adding to the resulting melt the following component (b) or the component (b) and the remainder of the component (a) and kneading the resulting mixture to prepare a resin composition having a melt flow rate of 1 to 100 g/10 min, and then molding the resin composition into a molded product in which the breakage rate of the component (b) is 30% by weight or less: (a) 100 parts by weight of a crystalline propylene polymer having a melt flow rate of 1 to 300 g/10 min and (b) 3 to 80 parts by weight of a filler in the form of hollow particles having a mean particle density (true density) of 0.1 to 0.9 g/cm.sup.3, as measured according to ASTM-D2840, a mean particle diameter of 7 to 100 .mu.m and a 10%-by-weight breakage pressure resistance of 100 kg/cm.sup.2 or more, as measured according to ASTM-D3102.