Title:
BIAXIALLY STRETCHED POLYPROPYLENE FILM FOR CAPACITORS
Document Type and Number:
WIPO Patent Application WO/2013/105552
Kind Code:
A1
Abstract:
The present invention relates to a biaxially stretched polypropylene film for capacitors, which contains an isotactic polypropylene. This biaxially stretched polypropylene film for capacitors is characterized in that: the weight average molecular weight (Mw) of the isotactic polypropylene as determined by gel permeation chromatography (GPC) is from 250,000 to 450,000 (inclusive); the molecular weight distribution (Mw/Mn) of the isotactic polypropylene is from 7 to 12 (inclusive); the Mz/Mn of the isotactic polypropylene is from 20 to 40 (inclusive); and the isotactic polypropylene gives a molecular weight distribution curve in which the difference obtained by subtracting the differential distribution value corresponding to a logarithmic molecular weight (Log(M)) of 6 from the differential distribution value corresponding to a Log(M) of 4.5 is from 8% to 20% (inclusive) relative to the differential distribution value corresponding to a Log(M) of 4.5. The present invention is capable of providing an ultrathin biaxially stretched polypropylene film for capacitors, which has excellent heat resistance and excellent withstand voltage performance.
Inventors:
ISHIWATA TADAKAZU (JP)
SHISHIDO YUICHI (JP)
SHISHIDO YUICHI (JP)
Application Number:
PCT/JP2013/050120
Publication Date:
July 18, 2013
Filing Date:
January 08, 2013
Export Citation:
Assignee:
OJI HOLDINGS CORP (JP)
International Classes:
H01G4/18; C08F4/655; C08F10/06; C08J5/18; C08K5/13; C08L23/12
Domestic Patent References:
| WO2009060944A1 | 2009-05-14 |
Foreign References:
| JP2006143975A | 2006-06-08 | |||
| JP2010280795A | 2010-12-16 | |||
| JPS58104907A | 1983-06-22 |
Attorney, Agent or Firm:
SHIGA Masatake et al. (JP)
Masatake Shiga (JP)
Masatake Shiga (JP)
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Claims: