	US 12,291,687 B2
	Lubricating oil composition
Yasunori Shimizu, Tokyo (JP)
Assigned to IDEMITSU KOSAN CO., LTD., Chiyoda-ku (JP)
Appl. No. 18/552,723
Filed by IDEMITSU KOSAN CO., LTD., Chiyoda-ku (JP)
PCT Filed Mar. 2, 2022, PCT No. PCT/JP2022/008758 § 371(c)(1), (2) Date Sep. 27, 2023, PCT Pub. No. WO2022/209541, PCT Pub. Date Oct. 6, 2022.
Claims priority of application No. 2021-057788 (JP), filed on Mar. 30, 2021.
Prior Publication US 2024/0199971 A1, Jun. 20, 2024
Int. Cl. C10M 141/08 (2006.01); C10N 30/00 (2006.01); C10N 30/02 (2006.01); C10N 40/25 (2006.01)

CPC C10M 141/08 (2013.01) [C10M 2215/28 (2013.01); C10M 2219/024 (2013.01); C10N 2030/02 (2013.01); C10N 2030/42 (2020.05); C10N 2030/45 (2020.05); C10N 2040/25 (2013.01)]

20 Claims

1. A lubricating oil composition, comprising:

a base oil;

an aromatic carboxylic acid ester having one or more hydroxyl groups; and

a sulfur-based antioxidant,

wherein a content of phosphorus atoms is 0.06% by mass or less, based on a total amount of the lubricating oil composition, a sulfated ash content is 0.6% by mass or less, based on the total amount of the lubricating oil composition, and a content ratio of the sulfur-based antioxidant to the aromatic carboxylic acid ester by mass is in a range of 0.20 to 3.0.