Polypropylene film, polypropylene film integrated with metal layer, and film capacitor
AssigneeOji Holdings Corporation
InventorsTatsuji Ishida, Takeshi Tominaga, Tadakazu Ishiwata
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Abstract
Provided is a polypropylene film having a high dielectric breakdown strength at high temperatures. Provided is a polypropylene film in which a polypropylene resin constituting the polypropylene film has a molecular-weight distribution (Mw/Mn) of the weight-average molecular weight Mw to the number-average molecular weight Mn of has a Z-average molecular weight Mz of 950,000-1,500,000, and has a weight proportion w of 2.6-4.2% in an integral molecular-weight distribution curve when the logarithmic molecular weight Log(M) is 4.0.
Claims11
A polypropylene film comprising a polypropylene resin, the polypropylene resin having a molecular-weight distribution (Mw/Mn) of a weight-average molecular weight Mw to a number-average molecular weight Mn of 5.0 or more and 6.9 or less, having a Z-average molecular weight Mz of 950,000 or more and 1,500,000 or less, and having a weight proportion w of 2.6% or more and 4.0% or less when a logarithmic molecular weight Log (M) is 4.0 in an integral molecular-weight distribution curve.
A film capacitor comprising a metal layer-integrated polypropylene film comprising:
- a polypropylene film comprising a polypropylene resin, the polypropylene resin having a Z-average molecular weight Mz of 950,000 or more and 1,500,000 or less and having a dielectric breakdown strength (DCES) at a direct current voltage at 120° C. of 530 V/μm or more;
- and
- a metal layer laminated on one surface or both surfaces of the polypropylene film or a configuration in which a plurality of the metal layer-integrated polypropylene films are laminated,
- wherein an insulation resistance value at an ambient temperature of 115° C. is 20 MΩ·μF or more.
Dependencies are inferred from the claim text.