	US 12,215,229 B2
	Lip seal
Naohisa Ikegami, Tokyo (JP)
Assigned to EAGLE INDUSTRY CO., LTD., Tokyo (JP)
Filed by EAGLE INDUSTRY CO., LTD., Tokyo (JP)
Filed on Sep. 23, 2021, as Appl. No. 17/483,783.
Claims priority of application No. 2021-030258 (JP), filed on Feb. 26, 2021; and application No. 2021-093800 (JP), filed on Jun. 3, 2021.
Prior Publication US 2022/0275176 A1, Sep. 1, 2022
Int. Cl. C08L 9/00 (2006.01); C08K 3/04 (2006.01); C08K 3/36 (2006.01); F16J 15/3204 (2016.01); F16J 15/3284 (2016.01)

CPC C08L 9/00 (2013.01) [C08K 3/04 (2013.01); C08K 3/36 (2013.01); F16J 15/3204 (2013.01); F16J 15/3284 (2013.01)]

9 Claims

1. A rubber lip seal which is fixed to a housing and slides with a shaft that rotates relatively with the housing, wherein:

the lip seal comprises a rubber comprising hydrogenated nitrile rubber, ethylene propylene diene monomer rubber or fluoro rubber, a reinforcing filler material, and a non-reinforcing filler material having an aspect ratio in a range of 1 or more and 30 or less;

the lip seal contains 1 part by weight or more and 150 parts by weight or less of the reinforcing filler material and 5 parts by weight or more and 90 parts by weight or less the non-reinforcing filler material per 100 parts by weight of the rubber; and

a roughness Ra of a sliding surface of the lip seal is 0.01 to 0.45 μm.