COMPOSITE SEMIPERMEABLE MEMBRANES AND PROCESS FOR PRODUCTION THEREOF

摘要

The invention aims at providing a process by which composite semipermeable membrane excellent in contamination resistance, particularly microbial contamination resistance can be easily produced at a low cost; and composite semipermeable membranes produced by the process. The invention relates to a process for the production of semipermeable membrane which comprises the step of forming a skin layer containing a polyamide resin prepared by reacting a polyfunctional amine component with a polyfunctional acid halide component on the surface of a porous substrate, the step of forming a polymer layer (A) containing a silver salt on the skin layer directly or through other layer, and the step of reducing the silver salt to precipitate metallic silver in the polymer layer (A) and/or on the surface thereof.