Toray Industries, Inc.

Toyo Seikan Kaisha, Ltd.

Masayoshi Asakura

Tetsuya Tsunekawa

Shigeru Tanaka

Itsuo Nagai

Kenichi Etou

Masanori Aizawa

Hiroki Sano

Kenji Yabe

Takumi Hirano

Tetsuya Yamagata

A polyester film for use in a capacitor having high heat resistance, which consists of a biaxially oriented film containing a polyester (A) as a main component and a polyimide (B) and has a glass transition temperature of 105&#xb0; C. to 145&#xb0; C. and an elongation at break in the machine direction of 70% to 150%, offers a high glass transition temperature and excellent insulation volume resistance and insulation breakdown voltage at high ambient temperatures. This film can produce a metallized film for use in a capacitor having high heat resistance and also a film capacitor having high heat resistance.

Polyester film for heat-resistant capacitor, metallized film thereof, and heat-resistant film capacitor containing the same

A biaxially oriented polyester film that is 7.0 GPa or more in either the Young's modulus in the machine direction (YmMD) or in the transverse direction (YmTD), and in the range of 55&deg; or more and 85&deg; or less in the circumferential half-width of the diffraction line from the crystal plane in the direction of the polyester's backbone chain that is determined through crystal orientation analysis by wide angle X-ray diffractometry performed while rotating the polyester film around its normal. The film is high in rigidity in all directions within the film plane, high in tear resistance, high in dimensional stability, and resistant to deformation under load, and have very great industrial advantages as material for high-density magnetic recording media, with wide applicability as material for electrostatic capacitor, heat transfer ribbon, and base paper for thermosensitive stencil printing.

Process of making biaxially oriented polyester films

Disclosed is a biaxially oriented polyester film that is 7.0 GPa or more in either the Young's modulus in the machine direction (YmMD) or in the transverse direction (YmTD), and in the range of 55&deg; to 85&deg; in the circumferential half-width of the diffraction line from the crystal plane in the direction of the polyester's backbone chain that is determined through crystal orientation analysis by wide angle X-ray diffractometry performed while rotating the polyester film around its normal. The film is high in rigidity in all directions within the film plane, high in tear resistance, high in dimensional stability, and resistant to deformation under load, and have very great industrial advantages as material for high-density magnetic recording media, with wide applicability as material for electrostatic capacitor, heat transfer ribbon, and base paper for thermosensitive stencil printing.

Biaxially oriented polyester films and their production methods

A transparent gas barrier biaxially oriented polypropylene film, comprising a base layer mainly composed of a polypropylene polymer, a polyolefin resin layer of 30 to 85 J/g in the heat of fusion formed at least on one side of the base layer, and an imperfectly oxidized alumina layer formed on the polyolefin resin layer, wherein the aluminum metal concentration in the internal portion of the imperfectly oxidized alumina layer is higher than that in the surface of the layer and that in the interface with the polyolefin resin layer, and the aluminum metal content of the imperfectly oxidized alumina layer is kept in a range of 10 to 200% nm. It is a transparent metallized gas barrier biaxially oriented polypropylene film excellent in moisture and oxygen barrier properties and also excellent in the gas barrier properties after elongation.

Transparent gas barrier biaxially oriented polypropylene film, a

The present invention relates to a biaxially oriented polypropylene film and a capacitor made thereof. The biaxially oriented polypropylene film of the invention is a biaxially oriented polypropylene film that is 98-99.5% in isotacticity, above 99% in isotactic pentad fraction, and 1-4% in the sum of the machine- and transverse-direction heat shrinkage at 120.degree. C., or a biaxially oriented polypropylene film that is less than 10 ppm.multidot.% in the product of the film's ash content and internal haze and is above 99% in isotactic pentad fraction. With this constitution, the biaxially oriented polypropylene film of the present invention has good dielectric properties at high temperatures. Furthermore, the capacitor of the invention can be used safely for a long life at operating temperatures higher by up to 20.degree. C. than the maximum operating temperature of 85.degree. C. of the conventional biaxially oriented polypropylene films.

Biaxially oriented polypropylene film and a capacitor made thereof

A polyester film-heat-bonded metal sheet is provided, which comprises a biaxially oriented polyester film or films, heat-bonded to a metal sheet by means of an adhesive layer interposed therebetween. The adhesive layer is made of a polyblend comprised of, based on the weight of the polyblend, 5 to 80 wt. % of at least one high melting point polyester having a melting point of at least 200.degree. C. and 20 to 95 wt. % of at least one low melting point polyester having a melting point of at least 100.degree. C., but not higher than a temperature which is 5.degree. C. lower than the melting point of the high melting point polyester. The polyblend may contain a minor amount of a polyolefin resin. The polyester film-heat-bonded metal sheet has good formability and is suitable for cans and other containers. The containers exhibit enhanced impact resistance, adaptability to retort treatment and corrosion resistance.

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Shiga, Japan

Masayoshi Asakura