US 12,377,400 B2
Water purification filter
Maiko Sakai, Kyoto (KR); and Norihiro Naito, Kyoto (KR)
Assigned to UNITIKA LTD., Osaka (KR)
Appl. No. 17/801,397
Filed by UNITIKA LTD., Osaka (KR)
PCT Filed Jan. 22, 2021, PCT No. PCT/JP2021/002327
§ 371(c)(1), (2) Date Aug. 22, 2022,
PCT Pub. No. WO2021/171854, PCT Pub. Date Sep. 2, 2021.
Claims priority of application No. 2020-032300 (KR), filed on Feb. 27, 2020; and application No. 2020-147398 (KR), filed on Sep. 2, 2020.
Prior Publication US 2023/0113769 A1, Apr. 13, 2023
Int. Cl. B01J 20/20 (2006.01); B01J 20/26 (2006.01); B01J 20/28 (2006.01); C02F 1/28 (2023.01)
CPC B01J 20/20 (2013.01) [B01J 20/262 (2013.01); B01J 20/28011 (2013.01); B01J 20/28023 (2013.01); C02F 1/28 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A water purification filter obtained by winding a nonwoven sheet containing fibrous activated carbon and a heat fusible core-sheath composite fiber and then heat fusing the sheet, wherein
a sheath portion of the heat fusible core-sheath composite fiber contains a biodegradable polyester resin having a melting point of 80 to 140° C.,
a core portion of the heat fusible core-sheath composite fiber contains a synthetic resin having a melting point at least 20° C. higher than the melting point of the biodegradable polyester resin, and
the water purification filter has a density of 0.12 to 0.30 g/cm3 and a specific surface area of 500 to 1800 m2/g.