Separation membrane element and method for producing composite semipermeable membrane

摘要

The purpose of the present invention is to provide a separation membrane element which has high boron removal performance and high water permeation performance, while being reduced in elution. Specifically provided is a separation membrane element which comprises a polyamide separation function layer on a microporous supporting body that is composed of a base and a porous supporting layer. The degree of yellowing of the polyamide separation function layer is 10-40 (inclusive), and the concentration of material eluted from the base is 1.0 × 10