	US 12,139,612 B2
	Rubber composition and tire
Kensuke Washizu, Kobe (JP)
Assigned to Sumitomo Rubber Industries, Ltd., Hyogo (JP)
Appl. No. 17/615,150
Filed by Sumitomo Rubber Industries, Ltd., Hyogo (JP)
PCT Filed May 15, 2020, PCT No. PCT/JP2020/019428 § 371(c)(1), (2) Date Nov. 30, 2021, PCT Pub. No. WO2020/246218, PCT Pub. Date Dec. 10, 2020.
Claims priority of application No. 2019-104592 (JP), filed on Jun. 4, 2019.
Prior Publication US 2022/0235209 A1, Jul. 28, 2022
Int. Cl. C08L 9/06 (2006.01); B60C 1/00 (2006.01); B60C 11/00 (2006.01); B60C 11/03 (2006.01)

CPC C08L 9/06 (2013.01) [B60C 1/0016 (2013.01); B60C 11/0008 (2013.01); B60C 11/033 (2013.01); B60C 2011/0025 (2013.01); B60C 2011/0033 (2013.01); B60C 2011/0341 (2013.01); C08L 2205/035 (2013.01)]

15 Claims

1. A rubber composition, having a hardness that reversibly changes with water and satisfying the following relationships (1) and (2):

Hardness when dry−Hardness when water-wet≥1 (1)

wherein each hardness represents a JIS-A hardness at 25° C. of the rubber composition; and

tan δ at 70° C. when dry≥0.18 (2)

wherein the tan δ at 70° C. represents a loss tangent measured at 70° C., an initial strain of 10%, a dynamic strain of 2%, and a frequency of 10 Hz.