US 12,110,382 B2
Polyolefin microporous membrane
Akihisa Yamashita, Tokyo (JP); and Manabu Sekiguchi, Tokyo (JP)
Assigned to Asahi Kasei Kabushiki Kaisha, Tokyo (JP)
Appl. No. 16/753,121
Filed by Asahi Kasei Kabushiki Kaisha, Tokyo (JP)
PCT Filed Aug. 9, 2019, PCT No. PCT/JP2019/031755
§ 371(c)(1), (2) Date Sep. 10, 2020,
PCT Pub. No. WO2020/179101, PCT Pub. Date Sep. 10, 2020.
Claims priority of application No. 2019-038419 (JP), filed on Mar. 4, 2019.
Prior Publication US 2021/0214535 A1, Jul. 15, 2021
Int. Cl. C08L 23/06 (2006.01); C08J 9/26 (2006.01); H01M 50/409 (2021.01); H01M 50/417 (2021.01); H01M 50/491 (2021.01); H01M 50/494 (2021.01)
CPC C08L 23/06 (2013.01) [C08J 9/26 (2013.01); H01M 50/409 (2021.01); H01M 50/417 (2021.01); H01M 50/491 (2021.01); C08J 2323/06 (2013.01); C08J 2423/12 (2013.01); H01M 50/494 (2021.01)] 13 Claims
 
1. A polyolefin microporous membrane having a loss tangent (tan δ) at 230° C. of 0.35 or more and less than 0.60 in melt viscoelasticity measurement.