Lubricating oil composition

Patent metadata

Field	Value
Publication number	US-9458402-B2
Application number	US-201314389614-A
Country	US
Kind code	B2
Filing date	Mar 29, 2013
Priority date	Mar 30, 2012
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

Provided by the present invention is a lubricating oil composition having a low friction coefficient (traction coefficient) and a superior fluidity at low temperature, suitable as a transmission oil including an automatic transmission oil, by using a base oil which contains a mineral oil satisfying the conditions that (1) kinetic viscosity at 100° C. is in the range of 5 mm 2 /s or more to 8 mm 2 /s or less, (2) viscosity index is 130 or more, and (3) % C P by a ring analysis (n-d-M method) is 80 or more.

First claim

The invention claimed is:

1. A lubricating oil composition, comprising a base oil, wherein the base oil comprises:
(A) a mineral oil satisfying conditions (1) to (3):
(1) kinetic viscosity at 100° C. is in the range of 5 mm 2 /s or more to 8 mm 2 /s or less;
(2) viscosity index is 130 or more; and
(3) % C P by a ring analysis (n-d-M method) is 80 or more;

(B-1) a mineral oil having a kinetic viscosity at 100° C. in the range of 1.5 mm 2 /s or more to 4.5 mm 2 /s or less and a pour point of −25° C. or lower; and
(B-2) a synthetic oil having a kinetic viscosity at 100° C. in the range of 1.5 mm 2 /s or more to 6.5 mm 2 /s or less and a pour point of −30° C. or lower,

and the lubricating oil composition is adapted to function as an oil for a transmission.

2. The lubricating oil composition according to claim 1 , wherein the viscosity index of the mineral oil (A) is 160 or less.

3. The lubricating oil composition according to claim 1 , wherein in the mineral oil (A):
% C P is in the range of 80 or more to 95 or less;
% C N is in the range of 5 or more to 20 or less; and
% C A is 1.0 or less.

4. The lubricating oil composition according to claim 1 , wherein the kinetic viscosity at 100° C. of the mineral oil (A) is in the range of 5.5 mm 2 /s or more to 7.5 mm 2 /s or less.

5. The lubricating oil composition according to claim 1 , wherein:
the mineral oil (B-1) has a kinetic viscosity at 100° C. in the range of 2.0 mm 2 /s or more to 4.0 mm 2 /s or less and a pour point of −25° C. or lower; and
the synthetic oil (B-2) has a kinetic viscosity at 100° C. in the range of 1.7 mm 2 /s or more to 6.2 mm 2 /s or less and a pour point of −30° C. or lower.

6. The lubricating oil composition according to claim 5 , wherein the base oil comprises:
40% or more to 75% or less by mass of the mineral oil (A); and
25% or more to 60% or less by mass of a combined mass of the mineral oil (B-1) and the synthetic oil (B-2),
based on a total mass of the base oil.

7. The lubricating oil composition according to claim 1 , wherein in an entirety of the base oil:
% C P is in the range of 80 or more to 95 or less;
% C N is in the range of 5 or more to 20 or less; and
% C A is 1.0 or less.

8. The lubricating oil composition according to claim 1 , further comprising at least one additive selected from the group consisting of an antioxidant, an extreme pressure agent, an anti-wear agent, a dispersant, a metallic detergent, an oiliness improver, a rust inhibitor, a metal deactivator, a corrosion inhibitor, a pour point depressant, and a defoaming agent.

9. An automatic transmission, comprising the lubricating oil composition of claim 1 .

10. A lubricating oil composition, comprising a base oil, wherein the base oil comprises:
(A) a mineral oil satisfying conditions (1) to (3):
(1) kinetic viscosity at 100° C. is in the range of 5 mm 2 /s or more to 8 mm 2 /s or less;
(2) viscosity index is 130 or more; and
(3) % C P by a ring analysis (n-d-M method) is 80 or more;

(B) at least one base oil selected from the group consisting of
(b1) a mineral oil having a kinetic viscosity at 100° C. in the range of 1.5 mm 2 /s or more to 4.5 mm 2 /s or less and a pour point of −30° C. or lower, and
(B-2) a synthetic oil having a kinetic viscosity at 100° C. in the range of 1.5 mm 2 /s or more to 6.5 mm 2 /s or less and a pour point of −30° C. or lower,

and the lubricating oil composition is adapted to function as an oil for a transmission.

Assignees

• Idemitsu Kosan Co

Inventors

• TAKEKAWA Daisuke

Classifications

• C10N2020/065

  Saturated Compounds · CPC title

• C10N2040/044

  for manual transmissions · CPC title

• C10N2040/042

  for automatic transmissions · CPC title

• C10N2040/045

  for continuous variable transmission [CVT] · CPC title

• C10N2030/08

  Resistance to extreme temperature · CPC title