Chisso Corporation

Yuya Ishimoto

Takanori Nakashima

Chikashi Okayama

Shinichi Akitaya

Yoshitaka Sumi

Noriaki Saito

Yasuhiro Mochizuki

Yoshitaka Morimoto

Yasuhiro Shiraishi

Shinji Nakata

Hiroyuki Maehara

A propylene resin composition is constructed so as to contain (A) a propylene-&agr;-olefin random copolymer with the content of a propylene unit of 99.1 to 99.9% by weight, and (B) a propylene-&agr;-olefin random copolymer with the content of a propylene unit of 70 to 90% by weight, in the specified proportion, and to have the specified loss tangent (tan &dgr;) and storage elastic modulus (E&prime;), in the temperature dependence of dynamic viscoelasticity. Thereby, the propylene resin composition is provided, suitable as a raw material for shaped article having a well-balanced combination of transparency, stress-whitening resistance; impact resistance at low temperatures, and further heat resistance.

Propylene resin composition

To provide a uniaxially oriented polypropylene-based film excellent in tensile elongation along the TD direction and transparence, and generating less fibers when it is torn, a film-forming material which comprises a polypropylene-based resin material consisting of 40 to 95% by weight of crystalline polypropylene, and 60 to 5% by weight of propylene-&agr;-olefin copolymer dispersed as particles in the crystalline polypropylene is uniaxially oriented to afford a uniaxially oriented polypropylene-based film, wherein the particles of the copolymer have an aspect ratio (L/D) of mean dispersed particle length (L) to mean dispersed particle diameter along the film thickness direction (D) of 100 or more in a cross section of the film along the MD direction, and the mean dispersed particle diameter of 0.10 &mgr;m or less.

Uniaxially oriented polypropylene-based film

To provide an economically advantageous biaxially oriented polypropylene-based film, which is excellent in straight cuttability along the MD direction, strength along the TD direction and transparency, a film-forming material which comprises a polypropylene-based resin material consisting of 40 to 88% by weight of crystalline polypropylene, and 60 to 12% by weight of propylene-&agr;-olefin copolymer dispersed as particles in the crystalline polypropylene is biaxially oriented to afford a biaxially oriented polypropylene-based film wherein the particles of the copolymer have a mean dispersed particle diameter of 0.1 &mgr;m or less along the TD direction.

Biaxially oriented polypropylene-base film

An unoriented polypropylene-based film or sheet possessing excellent impact resistance at low temperature, transparency, heat resistance at low temperature and excellent tear strength and/or stress whitening resistance. A molding material which comprises a polypropylene-based resin material comprising 40 to 80% by weight of crystalline polypropylene and 60 to 20% by weight of propylene-&agr;-olefin copolymer containing 20 to 80% by weight of propylene polymerization units, the propylene-&agr;-olefin copolymer dispersed as particles in the crystalline polypropylene, is unoriently molded to afford a film-shaped or sheet-shaped molding, wherein the particle diameter have an aspect ratio (L/D) of mean dispersed particle length (L) to mean dispersed particle diameter along the thickness of the molding (D) of 30 or more in a cross section of the molding along the MD direction, and the mean dispersed particle diameter of 0.3 &mgr;m or less.

Unoriented polypropylene molding

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Chiba, Japan

Yuya Ishimoto