Patent ID: 9643209
Date: 2017-05-09
CPC Classifications: B01D,B05D

Claim:
1. A method of manufacturing a reverse osmosis membrane, the method comprising: forming a polysulfone layer with a plurality of pores by applying a solution including a polymer having a sulfonic acid group and a mixed solvent containing first and second solvents having different solubility parameter values to a surface of a porous support; and forming a polyamide active layer on the polysulfone layer, wherein the first solvent is N,N-dimethylformamide (DMF), and the second solvent is γ-butyrolactone (GBL), the first solvent and the second solvent being mixed in a ratio of 80:20 to 60:40, and wherein a percentage of the plurality of pores having a diameter of 40 nm or greater in the surface of the polysulfone layer is from 0.20 to 0.28%.