| 摘要 |
PROBLEM TO BE SOLVED: To provide a wound body capable of obtaining a microporous film excellent in cycle characteristics.SOLUTION: The wound body comprises a core having a cylindrical form, and a microporous film wound around the core, where the elongation γ of the microporous film in a TD direction is not less than 5.0 μm and not greater than 100 μm when measured at 50°C for 70 min. with a weight of 1.0 g by thermomechanical analysis, and the maximum outer diameter difference (ΔR1) in a variation of diameters measured at a center in a width direction of the core is not greater than 0.30 mm.SELECTED DRAWING: None |
