Patent ID: 8518310

Claim:
A process for producing a dried composite semipermeable membrane comprising: preparing a composite semipermeable membrane comprising: a porous support; and a skin layer including a polyamide resin obtained by reaction between a polyfunctional amine component and a polyfunctional acid halide component formed on a surface of the porous support, wherein a first surface of the composite semipermeable membrane contains the skin layer and a second surface of the composite semipermeable membrane contains the porous support; preparing a washed composite semipermeable membrane by washing the composite semipermeable membrane; preparing a treated composite semipermeable membrane by contact of a moisturizing solution including a moisturizer and a hydrophilization agent only to the second surface of the washed composite semipermeable membrane and by contact of a protecting solution only to the first surface the washed composite semipermeable membrane; and drying the treated composite semipermeable membrane.