Chisso Corporation

Chikashi Okayama

Takanori Nakashima

Noriaki Saito

Yuya Ishimoto

Masami Kimura

Shinichi Akitaya

Yoshitaka Sumi

Shinji Nakata

Yasuhiro Mochizuki

Jun Saito

Akira Yamauchi

Kazuhiro Kimura

Yasuhiro Shiraishi

Michitaka Sasaki

Youichi Kugimiya

Hiroyuki Maehara

Hirohisa Ishii

Junichiro Yokota

Toshiki Yamamoto

Yuji Ando

Yasuhiko Nakagawa

Shouji Kawano

Kunio Gouda

Takehiko Enomoto

Masataka Sugimoto

Mayumi Wakata

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

Process for producing polypropylene or propylene random copolymer

Film having gas permeability

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

A propylene polymer blend is disclosed which comprises (A) a propylene-&agr;-olefin random copolymer with a propylene content of 90 to 99% by weight and (B) a propylene-&agr;-olefin random copolymer with a propylene content of 55 to 90% by weight, wherein the intrinsic viscosity (&lsqb;&eegr;,&rsqb;) of the copolymer B ranges from 1.3 to 3.5 dl/g, the ratio (&lsqb;&eegr;,&rsqb;/&lsqb;&eegr;,&rsqb;) of the intrinsic viscosity (&lsqb;&eegr;,&rsqb;) of the copolymer B to the intrinsic viscosity (&lsqb;&eegr;,&rsqb;) of the copolymer A ranges from 0.5 to 1.3 and a product ((&lsqb;&eegr;,&rsqb;/&lsqb;&eegr;,&rsqb;)&times;(W,/W,)) of the intrinsic ratio (&lsqb;&eegr;,&rsqb;/&lsqb;&eegr;,&rsqb;) of both copolymers and the weight ratio (W,/W,) of both copolymers ranges from 1.0 to 4.5. A polypropylene resin composition comprises 99 to 99.9999% by weight of the propylene polymer blend and 1 to 0.0001% by weight of an &agr;-crystal nucleating agent.

Propylene polymer blends, processes of producing the same and polypropylene resin compositions

A polypropylene composition for the production of various molded articles which are excellent in moldability, mold shrinkage factor on molding, rigidity, flexibility, impact resistance, in particular low-temperature impact resistance, transparency, gloss, stress-whitening resistance, and the balance thereof; various molded articles having the above properties; a propylene composition which is suitable for a base resin for the polypropylene composition; and a process for the production thereof. The propylene composition comprises a propylene homopolymer and a propylene-ethylene copolymer, the intrinsic viscosity of the copolymer (&lsqb;&eegr;&rsqb;,) is in the range of 1.7 to 2.8 dl/g, the intrinsic viscosity ratio of the homopolymer to the copolymer (&lsqb;&eegr;&rsqb;,/&lsqb;&eegr;&rsqb;,) is in the range of 0.7 to 1.2 and a product &lsqb;(W,/W,)&times;(&lsqb;&eegr;&rsqb;,/&lsqb;&eegr;&rsqb;,)&rsqb; of the weight ratio (W,/W,) of the homopolymer to the copolymer and the intrinsic viscosity ratio thereof is in the range of 1.0 to 3.0.

Propylene composition, process for preparing the same, polypropylene composition, and molded articles

A polypropylene composition which contains 0.01 to 5 parts by weight of an olefin (co)polymer (a) having an intrinsic viscosity of 15 to 100 dl/g, 100 parts by weight of a propylene homopolymer (b) having an intrinsic viscosity of 0.2 to 10 dl/g, and 28 to 300 parts by weight of an ethylene/propylene copolymer (c) having an intrinsic viscosity of 0.2 to 10 dl/g, and in which the ratio of the melt flow rate of the homopolymer (b) to that of the copolymer (c), MFR,/MFR,, is 0.3 to 4 and the product of the ratio of the intrinsic viscosity of the copolymer (c) to that of the homopolymer (b), &lsqb;&eegr;&rsqb;,/&lsqb;&eegr;&rsqb;,, and the weight ratio of the amount of the homopolymer (b) to that of the copolymer (c), W,/W,, is in the range of from 0.2 to 3.0. The composition has high melt tension, high crystallization temperature, and excellent thermal stability, and yields a molded article having excellent transparency, reduced molding shrinkage, and excellent resistance to whitening by impact or bending.

Polypropylene composition and process for producing the same

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

Polyolefin type resinous composition

Growing community of inventors

Ichihara, Japan

Chikashi Okayama