The present invention relates to a laminated sheet having adjacent dense layers and supporting layers, wherein the dense layer has a pore size of 0.1 m or less in pore length in the layer, the thickness of the layer is 0.1 m or more and 2 m or less, The void length of the void (a) having the longest gap length among the voids existing within 2 占 퐉 in the thickness direction from the interface with the support layer toward the support layer is 0.3 占 퐉 or more and exists within 2 占 퐉 or more and 4 占 퐉 in the thickness direction toward the support layer from the interface A water vapor permeable film having a void length of the void (b) having the longest void length of not less than 0.5 탆 and a void length of the void (b) being longer than a void length of the void (a). The present invention provides a water vapor permeable film having high water vapor permeability and low air leakage.
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