| 摘要 |
PROBLEM TO BE SOLVED: To obtain a base oil composition having improved flash point and low-temperature fluidity without deteriorating high-temperature traction coefficient by including a specific naphthenic synthetic lubricating base oil and a specific paraffinic synthetic lubricating base oil at a specific ratio. SOLUTION: The objective composition is produced by including (A) 80-98 wt.% of a naphthenic synthetic lubricating base oil having a flash point of <=180 deg.C and (B) 2-20 wt.% of a paraffinic synthetic lubricating base oil having a flash point higher than that of the component A. The component A is preferably a compound having a ring selected from cyclohexane ring, bicycloheptane ring and bicyclooctane ring, more preferably a compound having two or more rings selected from cyclohexane ring, bicyclo[2.2.1]heptane ring, bicyclo[3.2.1]octane ring, etc. The component B is poly-α-olefin, anα-olefin copolymer, etc. |
