Sumitomo Chemical Company, Limited

Takeshi Ebara

Toshio Sasaki

Kiyoshi Kawai

Kazuki Wakamatsu

Yoichi Obata

Hideaki Hori

Yoshihiro Miyoshi

Hiroyuki Tanimura

Hirofumi Jyohouji

Junichi Kimura

Koji Mizunuma

Hiroyuki Shiraishi

Kazuhiro Yamazaki

Yoshizumi Sasaki

Hiroyuki Kora

Syozo Kawamata

Hiroyuki Koura

Taiji Yamada

Shunji Yunoki

Mituharu Yamasaki

Tuyoshi Hashimoto

Akio Imai

Hajime Sadatoshi

Toshio Igarashi

Masayuki Tatsumi

Kooji Mizunuma

Eiji Sogabe

Hirofumi Jyohoji

Shozo Kawamata

Shouzou Kawamata

Teruyosi Kiyota

Disclosed is a polymer composition comprising a copolymer of propylene, a specific amount of &#x3b1;-olefin having 4 or more carbon atoms and optionally a specific amount of ethylene and a specific 1-butene homopolymer or copolymer having a melting point of not lower than 60&#xb0; C. but lower than 125&#xb0; C., wherein the polymer composition contains a 20&#xb0; C. xylene-soluble portion of the polymer composition in an amount of from 5 to 45% by weight and the 20&#xb0; C. xylene-soluble portion has an intrinsic viscosity of 1.3 dl/g or higher. The polymer composition may optionally contain a specific propylene copolymer and/or a specific propylene homopolymer or copolymer having a melting point of from 150&#xb0; C. to 170&#xb0; C.

Polymer composition and film thereof

Disclosed is a biaxially oriented multilayer polypropylene film which has a substrate layer containing a polypropylene resin composition including 97 to 99.97% by weight of a propylene polymer (A) and 0.03 to 3% by weight of a surfactant and also has, on at least one side of this layer, a layer containing a polypropylene resin composition including 30 to 80% by weight of a propylene polymer (C) having a melting point of 150 to 170&#xb0; C. and 20 to 70% by weight of a propylene-based random copolymer (D) having a melting point of 120 to 149&#xb0; C. and including 1 to 14 mole % of ethylene and/or &#x3b1;-olefin.

Biaxially oriented multilayer polypropylene film

There are provided a polypropylene resin composition comprising:

Polypropylene resin composition and film

A process for a polyolefin-based resin composition, which comprises melt-kneading 100 parts by weight of a polyolefin-based resin and not less than 0.05 parts by weight and less than 2 parts by weight of polymer fine particles containing 0.10 to 90% by weight of a volatile component as an anti-blocking agent.

Process for producing polyolefin-based resin composition

Disclosed is a stretched film excellent in low-temperature heat sealability after corona treatment as well as that before corona treatment and/or in heat shrinkability, the stretched film being comprised of a layer comprising a copolymer of propylene with &agr;-olefin and/or ethylene such that in measurement of a DSC curve the amount of the heat absorbed in the temperature range of from T&minus;10 (&deg; C.) to T&plus;10 (&deg; C.) accounts for from 15 to 36% of the amount of the heat absorbed in the temperature range of from 53 to 170&deg; C., wherein T denotes a temperature (&deg; C.) at which a maximum endothermic peak appears in the DSC curve.

Stretched polypropylene film

Disclosed is a resin composition that comprises a propylene-based copolymer (X) consisting of two kinds of copolymeric components made up of propylene, &agr;-olefin and optionally ethylene which are characterized by ethylene content and &agr;-olefin content, the copolymer (X) exhibiting a specific endothermic behavior in DSC measurement; a crystalline olefin-based polymer (Z) having a melting point up to 115&deg; C.; and optionally a copolymer (Y) made up of propylene and &agr;-olefin and/or ethylene. The resin composition can be modified by addition of a propylene-based polymer (W) and/or a nucleating agent (N) and can yield a film superior in low-temperature heat sealability and antiblocking property.

Propylene-based resin composition and film made of the same

Disclosed is a resin composition that comprises a propylene-based copolymer (X) consisting of two kinds of copolymeric components made up of propylene, &agr;-olefin and optionally ethylene which are characterized by ethylene content an &agr;-olefin content, the copolymer (X) exhibiting a specific endothermic behavior in DSC measurement and a copolymer (Y) made up of propylene and &agr;-olefin and/or ethylene. The resin composition can afford a film superior in low-temperature heat sealability and antiblocking property.

Disclosed is a resin composition comprising from 20 to 99 parts by weight of a propylene-based polymer A having an MFR of from 0.3 to 20 g/10 min and a melting point Tm of from 125 to 140&deg; C. and from 1 to 80 parts by weight of a propylene-based polymer B having an MFR of from 21 to 200 g/10 min and a melting point Tm of from 135 to 170&deg; C., wherein a ratio Tm /Tm is less than 1, wherein a ratio MFR /MFR is 0.01<MFR /MFR <1 and wherein the resin composition has an MFR of from 0.3 to 20 g/10 min and a melting point of from 130 to 145&deg; C. A heat-shrinkable film obtained by stretching the composition at least uniaxially is also disclosed which is superior in rigidity, heat shrinkage, weld-cut sealability and stretch processability. Incorporation of a nucleating agent improves the transparency of the film.

Propylene-based resin composition and heat-shrinkable film

A polypropylene-based resin composition for stretched film, comprising 20 to 98 parts by weight of a propylene-based polymer(A) having an intrinsic viscosity &lsqb;&eegr;&rsqb; of 1.8 to 8 dl/g and a melting temperature Tm of 140 to 165 &deg; C. and 2 to 80 parts by weight of a propylene-based polymer(B) having an intrinsic viscosity &lsqb;&eegr;&rsqb; of 0.8 to 1.7 dl/g and a melting temperature Tm of 150 to 170&deg; C., wherein the ratio of Tm to Tm is less than 1, the ratio of the intrinsic viscosity &lsqb;&eegr;&rsqb; to the intrinsic viscosity &lsqb;&eegr;&rsqb; is more than 1 and less than 10, and the melt flow rate of the polypropylene-based resin composition is from 0.1 to 20 g/10 min.

Polypropylene-based resin composition for stretched film, process for producing the same and stretched film

A polypropylene resin composition having a melt flow rate of 0.5 to 20 g/10 min., comprising 20 to 98 parts by weight of a propylene-based polymer (A) having an intrinsic viscosity &lsqb;&eegr;&rsqb; measured in tetralin at 135&deg; C. of 2.0 to 5 dl/g and a melting point Tm determined from the peak temperature of the melting curve measured by a differential scanning calorie meter of 140 to 162&deg; C. and 2 to 80 parts by weight of a propylene-based polymer B having an intrinsic viscosity &lsqb;&eegr;&rsqb; measured in tetralin at 135&deg; C. of 0.80 to 1.8 dl/g and a melting point Tm determined from the peak temperature of the melting curve measured by a differential scanning calorie meter of 160 to 166&deg; C. and a process for producing the same.

Polypropylene resin composition and process for producing the same

A process for producing an anti-blocking agent master batch, which comprises melt-kneading 100 parts by weight of a polyolefin-based resin and 2 to 100 parts by weight of polymer fine particles containing 0.10 to 20% by weight of a volatile component as an anti-blocking agent.

Anti-blocking agent master batch

A process for producing an olefin polymer using a catalyst in which (A) is a solid catalyst component which includes magnesium, titanium, halogen and an electron donative compound as essential constituents; (B) is an organoaluminum component; and (C) is at least two electron donative compounds (&agr;) and (&bgr;), wherein the pentad stereoregularity of a xylene insoluble fraction of a homopolyproylene is 0<mmrr/mmmm&lE;0.0068 when electron donative compound (&agr;) is used in combination with (A) and (B), and the pentad stereoregularity of a xylene insoluble fraction homoproplyene of a is 0.0068<mmrr/mmmm &lE;0.0320 when electron donative compound (&bgr;) is used in combination with (A) and (B). A polypropylene produced in the process can be used to obtain a biaxially oriented film. (A) and (B). A polypropylene produced in the process can be used to obtain a biaxially oriented film.

Process for producing olefin polymers, olefin-polymerizing catalyst and polyproylene for biaxially oriented film produced with said catalyst

A catalyst system for polymerizing olefins is obtainable from (A) a solid component containing (A) magnesium, titanium and halogen and an electron donative compound which is an ether or ester; (B) an organoaluminum compound, and (C) at least two electron donative compounds, including an (.alpha.) and (.beta.) compound, wherein the total amount (C) compounds is 0.01 to 1 mole per mole of (B).

Process for producing olefin polymers, olefin-polymerizing catalyst and

An .alpha.-olefin polymer well balanced between stiffness, stickiness, processability, etc., which intrinsic viscosity [.eta.] is in the range of from 0.5 to 10 and which 20.degree. C. xylene-soluble fraction (CXS) content (% by weight) and 105.degree. C. xylene-insoluble fraction (XIS) content (% by weight) satisfy a condition of XIS.ltoreq.70.00-3.64CXS, provided that CXS is not smaller than 0 and not greater than 15; a specified .alpha.-olefin polymerizing catalyst for producing the polymer; a process for producing the polymer using the specified .alpha.-olefin polymerizing catalyst; a polypropylene for use in the production of a biaxially oriented film excellent in stretchability and satisfying the conditions (1)-(3) mentioned below; and a biaxially oriented film excellent in stiffness and dimensional stability obtained by stretching the polypropylene:

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Ichihara, Japan

Takeshi Ebara