Oji Holdings Corporation

Oji Paper Co., Ltd.

Tadakazu Ishiwata

Masahiro Nakata

Yoshimune Okuyama

Yoshinori Matsuo

Tatsuji Ishida

Akihiro Kakehi

Yuichi Shishido

Yoshikazu Fujishiro

Takeshi Tominaga

Fumio Jinno

Masahiro Yoda

Kazuo Ikeda

Toshiaki Taniike

Michiko Sueyoshi

Minoru Terano

Ikki Katada

Shigeo Murase

Manabu Furukawa

A biaxially stretched polypropylene film which has a thickness of from 1.0 μm to 3.5 μm, a tensile fracture stress at 135° C. of 70 MPa or more in a first direction, and a difference between the tensile fracture stress at 125° C. in the first direction and the tensile fracture stress at 135° C. in the first direction of from 0 MPa to 15 MPa (inclusive).

Biaxially stretched polypropylene film, metallized film, metallized film roll and film capacitor

A polypropylene film which is capable of suppressing blocking in a rolled polypropylene film. The polypropylene film has a first surface and a second surface, contains a polypropylene resin as a main component, and is configured such that: the Svk value (SvkA) of the first surface is 0.005 μm or more and 0.030 μm or less; the Spk value (SpkA) of the first surface is more than 0.035 μm and 0.080 μm or less; the Svk value (SvkB) of the second surface is 0.005 μm or more and 0.030 μm or less; and the Spk value (SpkB) of the second surface is 0.015 μm or more and 0.035 μm or less.

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

A polypropylene film which is capable of suppressing blocking in a rolled polypropylene film. The polypropylene film has a first surface and a second surface, contains a polypropylene resin as a main component, and is configured such that: the Svk value (SvkA) of the first surface is 0.005 &#x3bc;m or more and 0.030 &#x3bc;m or less; the Spk value (SpkA) of the first surface is more than 0.035 &#x3bc;m and 0.080 &#x3bc;m or less; the Svk value (SvkB) of the second surface is 0.005 &#x3bc;m or more and 0.030 &#x3bc;m or less; and the Spk value (SpkB) of the second surface is 0.015 &#x3bc;m or more and 0.035 &#x3bc;m or less.

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

The present invention relates to a biaxially stretched polypropylene film for capacitor. The biaxially stretched polypropylene film for capacitor of the present invention can suppress an increase in tan &#x3b4; and a decrease in the electrostatic capacitance even when the capacitor is used at a high voltage and an elevated temperature for a long duration.

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

A main object is to provide a biaxially stretched polypropylene film for capacitors that has high voltage resistance at high temperatures and excellent dielectric breakdown properties and that can be formed into an ultrathin film. Furthermore, a capacitor obtained by using the biaxially stretched polypropylene film for capacitors described above is provided. The biaxially stretched polypropylene film for capacitors, includes a polypropylene resin, and the film has a spacing value of (040) face of &#x3b1;-crystal measured by X-ray diffraction of 0.525 to 0.530 nm.

Biaxially stretched polypropylene film for capacitors

Provided is a biaxially stretched polypropylene film for capacitors having a thin thickness and having excellent initial voltage resistance and excellent long-term heat resistance and voltage resistance, and also provided is a metallized polypropylene film for capacitors. The polypropylene film for capacitors is obtained by biaxially stretching a polypropylene resin, the polypropylene film having a crystallite size of 122 &#x212b; or less as determined by the Scherrer's equation from the half width of the reflection peak from (040) plane of &#x3b1;-crystal measured by a wide angle X-ray diffraction method, and the polypropylene film having a value of birefringence &#x394;Nyz with respect to a thickness direction of 7.0&#xd7;10or more and 10.0&#xd7;10or less as measured by an optical birefringence measurement.

Biaxially stretched polypropylene film for capacitor

The present invention addresses the problem of providing a biaxially stretched polypropylene film for capacitors, which has high voltage resistance and excellent breakdown properties. The present invention also addresses the problem of providing a biaxially stretched polypropylene film for capacitors, which can be used suitably in a high-capacity capacitor to which a high voltage is to be applied under a higher temperature, and which preferably has a small thickness. The present invention relates to a biaxially stretched polypropylene film for capacitors, wherein a polypropylene resin which constitutes the polypropylene film has a number average molecular weight of 40,000 to 100,000 inclusive and a Z average molecular weight of 950,000 to 1,500,000 includes wherein, in a molecular weight distribution curve, the value of the difference obtained by subtracting a differential distribution value at a logarithmic molecular weight Log (M) of 6.0 from a differential distribution value at a logarithmic molecular weight Log (M) of 4.5 is &#x2212;15 to 11% inclusive.

The present invention addresses the problem of providing a biaxially stretched polypropylene film for capacitors, which has high voltage resistance and excellent breakdown properties. The present invention also addresses the problem of providing a biaxially stretched polypropylene film for capacitors, which can be used suitably in a high-capacity capacitor to which a high voltage is to be applied under a higher temperature, and which preferably has a small thickness. The present invention relates to a bi-axially stretched polypropylene film for capacitors, wherein a polypropylene resin which constitutes the polypropylene film has a number average molecular weight of 40,000 to 100,000 inclusive and a Z average molecular weight of 950,000 to 1,500,000 inclusive, wherein, in a molecular weight distribution curve, the value of the difference obtained by subtracting a differential distribution value at a logarithmic molecular weight Log (M) of 6.0 from a differential distribution value at a logarithmic molecular weight Log (M) of 4.5 is &#x2212;15 to 11% inclusive.

A biaxially stretched polypropylene film for a capacitor containing an isotactic polypropylene. The weight average molecular weight (Mw) of the isotactic polypropylene as measured by gel permeation chromatography (GPC) is 250,000 to 450,000, the molecular weight distribution Mw/Mn is 7 to 12 and Mz/Mn is 20 to 40, and the value of a difference obtained by subtracting a differential distribution value when the logarithmic molecular weight Log(M)=6 from a differential distribution value when Log(M)=4.5 on a molecular weight distribution curve thereof is 8% to 20%. The ultrathin biaxially stretched polypropylene film for a capacitor has superior heat resistance performance and withstands voltage performance.

A cast raw sheet for a capacitor film, prepared by heating and melting a polypropylene resin and extruding the resin from a T-die, wherein the polypropylene resin has: a weight average molecular weight, determined by gel permeation chromatography, of 100,000 or more and 500,000 or less; and a molecular weight distribution Mw/Mn of 7 or more, the resin contains 97% by mass or more of an isotactic component that is an extraction residue obtained by sequential extraction, and the cast raw sheet contains a &#x3b2;-form in a proportion of 1% or more and less than 20%, the proportion being determined by X-ray diffraction intensity.

Raw sheet for capacitor film and capacitor film

A biaxially-oriented polypropylene film for an ultra-thin capacitor that has superior heat resistance, withstand voltage performance and long-term durability. The film has a stereoregularity in which mesopentad fraction (mmmm) as determined by measurement of high temperature nuclear magnetic resonance (high temperature NMR) is between 94% and 98%, a weight average molecular weight (Mw) of 250,000 to 450,000, a molecular weight distribution (Mw/Mn) of 4 to 7, and on a molecular weight distribution curve, a difference determined by subtracting the differential distribution value when the logarithm of molecular weight Log(M)=6 from the differential distribution value when Log(M)=4.5 that is 9% to 15%. The film is fabricated using a polypropylene raw material resin in which the composition of the aforementioned molecular weight distribution has been adjusted by peroxidative decomposition treatment of a polypropylene resin.

Polypropylene film for capacitor

The present invention relates to a biaxially oriented polypropylene film containing: a polypropylene resin as a main component thereof, having a weight average molecular weight of 100,000 or more and 500,000 or less, the weight average molecular weight being determined by gel permeation chromatography, wherein at least one surface of the biaxially oriented polypropylene film has a protrusion volume of 2.0&#xd7;10&#x3bc;mor more and 3.0&#xd7;10&#x3bc;mor less, the protrusion volume being determined in an area of 560 &#x3bc;m&#xd7;745 &#x3bc;m using a super-depth surface profile measurement microscope by determining an average plane of the surface based on distances between plural points on the surface and an irradiation source of the super-depth surface profile measurement microscope and measuring a volume of protrusions projecting from the average plane.

Growing community of inventors

Chiba, Japan

Tadakazu Ishiwata