A membrane 12 that exhibits superior condensation resistance regardless of the type of
moisture-permeable resin, that has satisfactory adhesion between a
porous film and a reinforcing member, and that can be manufactured in a simple manner. The membrane 12 is a laminated article 23 containing a
porous film 20 and a reinforcing member 40, and the reinforcing member 40 has a
moisture-permeable resin layer 30 on the side of an interface 50 with the
porous film 20. To reliably form the
moisture-permeable resin layer (moisture-permeable resin film) 30, the average
pore diameter of the porous film 20 is preferably 0.01 to 10 μm, and the
porosity of the reinforcing member 40 is preferably 30 to 95%. According to the membrane 12 of the present invention, even if the moisture-permeable resin is water-soluble (for example,
polyvinyl alcohol), condensation resistance is still satisfactory. If the difference between the
critical surface tension γc2 of the reinforcing member 40 and the
critical surface tension γc1 of the porous film 20 (γc2−γc1) is set in advance to −5 mN / m or greater, the moisture-permeable resin layer 30 can be disposed internally at a specific location.