US 11,998,879 B2
Semipermeable membrane support
Keisuke Oyama, Tokyo (JP); Yusuke Shimizu, Tokyo (JP); Takahito Ochiai, Tokyo (JP); and Takao Masuda, Tokyo (JP)
Assigned to MITSUBISHI PAPER MILLS LIMITED, Tokyo (JP)
Appl. No. 16/494,114
Filed by MITSUBISHI PAPER MILLS LIMITED, Tokyo (JP)
PCT Filed Mar. 23, 2018, PCT No. PCT/JP2018/011595
§ 371(c)(1), (2) Date Sep. 13, 2019,
PCT Pub. No. WO2018/174224, PCT Pub. Date Sep. 27, 2018.
Claims priority of application No. 2017-058938 (JP), filed on Mar. 24, 2017; application No. 2017-068286 (JP), filed on Mar. 30, 2017; application No. 2017-253974 (JP), filed on Dec. 28, 2017; application No. 2018-001565 (JP), filed on Jan. 10, 2018; and application No. 2018-010982 (JP), filed on Jan. 25, 2018.
Prior Publication US 2020/0070103 A1, Mar. 5, 2020
Int. Cl. B01D 71/26 (2006.01); B01D 69/02 (2006.01); B01D 69/10 (2006.01); D01D 5/34 (2006.01); D01F 8/06 (2006.01); D04H 1/541 (2012.01); D04H 1/544 (2012.01)
CPC B01D 71/261 (2022.08) [B01D 69/02 (2013.01); B01D 69/1071 (2022.08); B01D 71/262 (2022.08); D01D 5/34 (2013.01); D01F 8/06 (2013.01); D04H 1/5412 (2020.05); D04H 1/5418 (2020.05); D04H 1/544 (2013.01); B01D 2325/24 (2013.01); D04H 1/5414 (2020.05); D10B 2321/021 (2013.01); D10B 2321/022 (2013.01); D10B 2401/20 (2013.01); D10B 2505/04 (2013.01)] 1 Claim
OG exemplary drawing
 
1. A semipermeable membrane support used by forming a semipermeable membrane thereon, which is a wet-laid nonwoven fabric consisting of core-sheath type conjugate fibers consisting of polypropylene as a core component and polyethylene as a sheath component, wherein
the core-sheath type conjugate fibers are core-sheath type conjugate fibers A having an average fiber diameter of more than 9 μm to not more than 11 μm, and a content of the core-sheath type conjugate fibers A is 100 mass %,
a Bekk smoothness and a 75° mirror surface glossiness of a coating surface on which a semipermeable member is to be formed of the semipermeable membrane support are more than a Bekk smoothness and a 75° mirror surface glossiness of a non-coating surface on an opposite side,
the Bekk smoothness of the coating surface on which the semipermeable membrane is to be formed of the semipermeable membrane support is 1.0 to 51.0 seconds and a ratio of the Bekk smoothness of the coating surface to that of the non-coating surface is 1.3:1.0 to 1.1:1.0, and
the 75° mirror surface glossiness in a MD direction of the coating surface of the semipermeable membrane support is 10 to 30%, the 75° mirror surface glossiness in a CD direction of the coating surface of the semipermeable membrane support is 8 to 25%, and a ratio of the surface glossiness in the MD direction of the coating surface to that of the non-coating surface is 1.0:0.9 to 1.0:0.7.