| 摘要 |
The purpose of the present invention is to provide a composite semipermeable membrane which maintains its performance at high temperature under high pressure and has high water permeability. This composite semipermeable membrane is provided with a substrate, a porous support layer disposed on the substrate, and a separation functional layer disposed on the porous support layer, wherein the separation functional layer contains a crosslinked wholly aromatic polyamide as a main component and has a wrinkled structure provided with protrusions and recesses. When the surface of the separation functional layer is observed in pure water by using atomic force microscopy, at least 40% of the protrusions have a deformation of 2.5 nm or less when pushed with a force of 5 nN, the median height of the protrusions is 100 nm or more, and the thickness of the separation functional layer in the protrusions is 20 nm or less. |
