| abstract |
A separation membrane ( 10 ) of the present disclosure includes: a separation functional layer ( 30 ) composed of a polyamide containing, as a monomer unit, at least one selected from the group consisting of piperazine and a piperazine derivative; and a coating ( 40 ) covering the separation functional layer ( 30 ) and containing a polymer having a repeating unit represented by the following formula (1). In the formula (1), N + is a nitrogen atom constituting a quaternary ammonium cation, and R 1 and R 2 are each independently a substituent containing a carbon atom bonded to the nitrogen atom. |