Sumitomo Chemical Company, Limited

Yoichi Obata

Takeshi Ebara

Junichi Kimura

Kazuki Wakamatsu

Toshio Sasaki

Minoru Takane

Koji Mizunuma

Makoto Satoh

Shunji Yunoki

Hiroyuki Tanimura

Hideaki Hori

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

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 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:

.alpha.-olefin polymers, .alpha.-olefin-polymerizing catalyst and

A polypropylene laminated film containing a crystalline polypropylene layer and, laminated on at least one side of the layer of the crystalline polypropylene, a layer of a copolymer of propylene and at least one .alpha.-olefin of from 4 to 10 carbon atoms having a specific composition, melt flow rate and molecular weight distribution in which the .alpha.-olefin content in the cold xylene soluble portion of the random copolymer is less than 1.7 times the .alpha.-olefin content in the copolymer and the random copolymer satisfies the mathematical expression,

Process for producing polypropylene laminated film

Polypropylene laminated film

A polypropylene composition which contains a polypropylene and one or more ingredients selected from an antistatic agent and a surface-treated or untreated fine powdery silica gives a propylene stretched film having a well-balanced transparency, slip property and blocking resistance.

Growing community of inventors

Sodegaura, Japan

Yoichi Obata