	US 12,545,850 B2
	Lubricating oil composition
Daisuke Nakaue, Tokyo (JP); and Masaya Kubota, Tokyo (JP)
Assigned to IDEMITSU KOSAN CO., LTD., Tokyo (JP)
Appl. No. 18/727,508
Filed by IDEMITSU KOSAN CO., LTD., Tokyo (JP)
PCT Filed Mar. 14, 2023, PCT No. PCT/JP2023/009819 § 371(c)(1), (2) Date Jul. 9, 2024, PCT Pub. No. WO2023/182073, PCT Pub. Date Sep. 28, 2023.
Claims priority of application No. 2022-048868 (JP), filed on Mar. 24, 2022.
Prior Publication US 2025/0084339 A1, Mar. 13, 2025
Int. Cl. C10M 171/04 (2006.01); C10M 159/00 (2006.01); C10M 169/04 (2006.01); C10N 20/02 (2006.01); C10N 30/00 (2006.01); C10N 40/25 (2006.01)

CPC C10M 171/04 (2013.01) [C10M 159/005 (2013.01); C10M 169/041 (2013.01); C10M 169/042 (2013.01); C10N 2020/02 (2013.01); C10N 2030/43 (2020.05); C10N 2030/45 (2020.05); C10N 2030/68 (2020.05); C10N 2040/252 (2020.05)]

14 Claims

1. A lubricating oil composition, comprising:

a base oil;

a comb polymer (A1) having a weight-average molecular weight, Mw, of less than 300,000 and a ratio of weight-average molecular weight to number average molecular weight, Mw/Mn, of 4.00 or less; and

a comb polymer (A2) having a Mw of 400,000 or more and a Mw/Mn of 6.00 or less,

wherein a mass content ratio A1/A2 in terms of resin content mass between the comb polymer (A1) and the comb polymer (A2) is in a range of 0.25 to 0.55.