Electric vehicle or hybrid vehicle lubricating oil composition
Provided is a lubricating oil composition for electric vehicle or hybrid vehicle having excellent gear properties, clutch properties, cooling properties, and electric insulating properties. The lubricating oil composition for electric vehicle or hybrid vehicle preparing by blending (A) a base oi and (B-1) a polyamide and/or (B-2) a polyol ester, the base oil (A) including (A-1) a synthetic oil having a kinematic viscosity at 100° C. of 1.0 to 10.0 mm 2 /s.
1. A lubricating oil composition for electric vehicle or hybrid vehicle, which is prepared by blending a mixture comprising:
(A) a base oil; and
(B-1) a polyamide which is a reaction product of an aliphatic polyamine having a total carbon number 6 to 30 and a monovalent fatty acid having 12 to 24 carbon atoms of the hydrocarbon group;
(B-2) a polyol ester which is a partial ester reaction product of a trivalent or multivalent aliphatic polyol and a fatty acid having 12 to 24 carbon atoms;
wherein:
the base oil (A) comprises:
(A-1) a poly-α-olefin, a hydrogenated product of a poly-α-olefin, or a mixture thereof, having a kinematic viscosity at 100° C. of 1.0 to 10.0 mm 2 /s,
(A-2) a mineral oil having a kinematic viscosity at 100° C. of 1.5 to 6 mm 2 /s, and
(A-3) a synthetic oil having a kinematic viscosity at 100° C. of more than 10.0 mm 2 /s and 100.0 mm 2 /s or less;
a blending amount of the component (A-1) is from 1.0 to 10.0% by mass on the basis of a total amount of the composition;
a blending amount of the component (A-2) is from 60.0 to 90.0% by mass on the basis of a total amount of the composition, and
a total blending amount of the component (B-1) and the component (B-2) is from 0.05 to 1.0% by mass on the basis of the total amount of the composition.
2. The lubricating oil composition according to claim 1 , wherein the component (A-1) is the poly-α-olefin or the hydrogenated product of the poly-α-olefin.
3. The lubricating oil composition according to claim 1 , wherein the blending amount of the component (A-1) is from 1.5 to 10.0% by mass on the basis of the total amount of the composition.
4. The lubricating oil composition according to claim 1 , which has a kinematic viscosity at 100° C. of 3 to 15 mm 2 /s.
5. The lubricating oil composition according to claim 1 , which has a viscosity index of 100 or more.
6. The lubricating oil composition according to claim 1 , which has a volume resistivity of 1.0×10 7 Ω·m or more.
7. The lubricating oil composition according to claim 1 , which has a Brookfield viscosity at −40° C. of 30,000 mPa·s or less.
8. The lubricating oil composition according to claim 1 , wherein the mixture does not include a dispersant.