Oji Holdings Corporation

Michiko Sueyoshi

Yoshimune Okuyama

Takeshi Tominaga

Masahiro Nakata

Tadakazu Ishiwata

Akihiro Kakehi

Yoshikazu Fujishiro

A polypropylene film which has a crystallite size of not more than 12.2 nm, the crystallite size being determined using Scherrer's equation from a full width at half maximum of the reflection peak from (040) plane of &#x3b1; crystal measured by a wide-angle X-ray diffraction method, and a volume resistivity of not lower than 6&#xd7;10&#x3a9;&#xb7;cm, the volume resistivity being calculated in accordance with equation I from a current value that is measured 1 minute after applying a voltage at a potential gradient of 200 V/&#x3bc;m in an environment at 100&#xb0; C. Equation I: volume resistivity=[(effective electrode area)&#xd7;(applied voltage)]/[(polypropylene film thickness)&#xd7;(current value)].

Polypropylene film, metal layer-integrated polypropylene film, and film capacitor

A biaxially stretched polypropylene film including a polypropylene resin and satisfying the following: (a) the crystallite size S, which is determined using the Scherrer equation from the full width at half maximum of the &#x3b1;-crystal (040) plane reflection peak as measured by wide-angle x-ray diffraction after treatment for 200 hours at 105&#xb0; C., is not more than 12.9 nm; and (b) the planar orientation coefficient &#x394;P, which is calculated from the birefringence values &#x394;Nyz and &#x394;Nxz with respect to the thickness direction as determined by optical birefringence measurement after treatment for 200 hours at 105&#xb0; C., is at least 0.013 (&#x394;P=(&#x394;Nyz+&#x394;Nxz)/2).

Biaxially stretched polypropylene film, metallized film for capacitors, and capacitor

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Tokyo, Japan

Michiko Sueyoshi