SEPARATION MEMBRANE AND MANUFACTURING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a separation membrane which has high water permeability, whose impurity-blocking rate is hardly lowered even when the surface of a separation-functional layer is scratched, whose porous resin layer is hardly peeled off from a porous base material and from which the clogged impurities can be easily removed. SOLUTION: The separation membrane has the porous resin layer formed on the surface of the porous base material and a combined layer formed by integrating a part of a resin forming the porous resin layer with the porous base material. Pores satisfying the inequality: 2dB<=dA (wherein dA is the average pore diameter on the surface of the side of the liquid to be treated; dB is the average pore diameter on the surface of the side of the permeated liquid) are formed on both surfaces of the porous resin layer.