| 摘要 |
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. |
