PROCESS FOR PRODUCING SEMIPERMEABLE COMPOSITE MEMBRANE

摘要

A semipermeable composite membrane which is excellent in water permeability and salt rejection, is reduced in the content of an unreacted polyfunctional amine ingredient remaining therein, and is of the type not necessitating membrane cleaning. The semipermeable composite membrane comprises a porous support and formed on the surface thereof a skin layer comprising a polyamide resin obtained by the interfacial polymerization of a polyfunctional amine ingredient and a polyfunctional acid halide ingredient, and is characterized in that the content of unreacted polyfunctional amine ingredient after formation of the skin layer, as measured without conducting cleaning for removing it, is 200 mg/m<SUP>2</SUP> or lower.