| 摘要 |
PROBLEM TO BE SOLVED: To restrain a self-discharge quantity, and to realize a thin type by setting an ion exchange quantity to a specific value in composite nonwoven fabric containing at least sulfonated polyolefine fiber. SOLUTION: A value of an ion exchange quantity is set to 0.04 to 0.30 meq/g. Sulfonated polystyrene fiber is used as a component of composite nonwoven fabric, and the average fiber diameter is desirably sat between 1 to 20 μm. When aliphatic polyolefine fiber is used as a mixing component, an average fiber diameter is desirably set between 0.5 to 15 μm, and ductility is desirably set not less than 40%. When polypropylene fiber is used as aliphatic polyolefine, the mixing ratio is desirably set to 25% to 85% of the whole nonwoven fabric weight, and a thickness of compounded nonwoven fabric is desirably set between 50 and 150 μm. The total weight of the compounded nonwoven fabric is desirably set between 15 to 100 g/m<2> . |
