US 12,239,942 B2
Separation membrane
Tomotsugu Miyabe, Osaka (JP); and Atsuhito Komoto, Osaka (JP)
Assigned to NITTO DENKO CORPORATION, Osaka (JP)
Filed by NITTO DENKO CORPORATION, Ibaraki (JP)
Filed on Jan. 4, 2021, as Appl. No. 17/140,771.
Application 17/140,771 is a continuation of application No. 16/455,328, filed on Jun. 27, 2019, granted, now 10,913,034.
Claims priority of application No. 2018-176627 (JP), filed on Sep. 20, 2018.
Prior Publication US 2021/0121830 A1, Apr. 29, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. B01D 69/12 (2006.01); B01D 67/00 (2006.01); B01D 71/56 (2006.01); B01D 71/58 (2006.01)
CPC B01D 69/1216 (2022.08) [B01D 67/00931 (2022.08); B01D 69/1251 (2022.08); B01D 71/56 (2013.01); B01D 71/58 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A separation membrane comprising:
a separation functional layer 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 covering the separation functional layer and containing a polymer having a repeating unit represented by the following formula (1):

OG Complex Work Unit Chemistry
wherein
N+ is a nitrogen atom constituting a quaternary ammonium cation,
R1 and R2 are each independently a substituent containing a carbon atom bonded to the nitrogen atom, and
an uppermost surface of the separation membrane comprises the coating.