PURPOSE: To manufacture a semipermeable composite membrane with high water- permeation and a high rate of elimination, is by a method wherein a thin film consisting of polyethyleneimine and an aminoalkylpiperidine is prepared on a porous support and treated with a crosslinking agent.
CONSTITUTION: A thin film consisting of polyethyleneimine and/or its derivative and an aminoalkylpiperidine and/or its derivative is prepared on a porous support, such as a cellulose ester, as a semipermeable membrane used for a separation method, such as reverse osmosis or ultrafiltration. The thin film is treated with a solution of a polyfunctional crosslinking agent, having at least two functional groups, per molecule, reacting with an amino group, and thermally treated. The semipermeable composite membrane thus obtained has high water-permeation and a high rate of elimination, changes little with time; and has a chlorine-resisting property.
HAYASHI TETSUZOU
KOBAYASHI HIROYA
OUMI RIYOUICHI
