To provide a separation membrane excellent in rigidity, perviousness, quality stability and thermal stability.
This separation membrane is a polyolefin-based two- or three-layered microporous film composed by combining a layer comprising polyethylene which is produced by a wet process and has the melting point of 125C, with a layer comprising 20-70 wt.% of polypropylene which is produced by a dry process and has a melting point of 160C and 80-30 wt.% of a heat-resistant filler. The micropore in the layer comprising polyethylene is made through the stretching/extraction process and its average size is 0.1 m. The macropore in the layer comprising polypropylene and the heat-resistant filler is formed by the interfacial expansion therebetween and has an average pore size of 1 m but 50 m, film thickness of 9-30 m, perforation strength of 0.15 N/m, permeability of 1.510-5 Darcy and melt fracture temperature of 170C.
JUNG INHWA
KANG GWIGWON
LEE YOUNGKEUN
| JP2006321151A | 2006-11-30 | |||
| JPH11317212A | 1999-11-16 | |||
| JPH11207888A | 1999-08-03 | |||
| JP2006321151A | 2006-11-30 |
| WO2004089627A1 | 2004-10-21 | |||
| WO2006038532A1 | 2006-04-13 | |||
| WO2004089627A1 | 2004-10-21 |
Makoto Suhara
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