Lubricating oil composition

Patent metadata

Field	Value
Publication number	US-9458405-B2
Application number	US-201314421206-A
Country	US
Kind code	B2
Filing date	Aug 19, 2013
Priority date	Aug 20, 2012
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

A lubricating oil composition includes: a base oil; a component (A) that is a dialkyl hydrogen phosphite; a component (B) that is a sulfur antioxidant; and a component (C) that is a polyalkenyl succinimide.
Since the lubricating oil composition of the invention exhibits an excellent lubricity to both iron metal and copper metal and an excellent heat stability, the lubricating oil composition of the invention is suitable for a shock absorber of an automobiles and the like.

First claim

The invention claimed is:

1. A lubricating oil composition, comprising, based on a total mass of the lubricating oil composition:
at least 77.9 mass % of a base oil;
from 0.4-0.6 mass % of a dialkyl hydrogen phosphite;
from 0.4-0.6 mass % of a sulfur antioxidant of formula (2)

wherein, in formula (2):
R 3 , R 4 , R 9 and R 10 are each a tertiary butyl group;
R 5 and R 8 are each an ethylene group; and
R 6 and R 7 are each an alkylene group; and

from 0.4-0.6 mass % of a polyalkenyl succinimide.

2. The composition of claim 1 , wherein the dialkyl hydrogen phosphite has formula (1):

wherein R 1 and R 2 are each independently an alkyl group having 8 to 16 carbon atoms.

3. The composition of claim 2 , wherein the dialkyl hydrogen phosphite of formula (1) is dilauryl hydrogen phosphite.

4. The composition of claim 1 , wherein R 6 and R 7 in formula (2) are each a methylene group.

5. The composition of claim 1 , wherein R 6 and R 7 in formula (2) are each an ethylene group.

6. The composition of claim 1 , wherein the polyalkenyl succinimide is polybutenyl succinimide.

7. A shock absorber comprising the composition of claim 1 .

8. The composition of claim 1 , comprising at least 82.9 mass % of the base oil based on the total mass of the composition.

9. The composition of claim 1 , comprising at least 87.9 mass % of the base oil based on the total mass of the composition.

10. The composition of claim 1 , comprising at least 92.9 mass % of the base oil based on the total mass of the composition.

Assignees

• Idemitsu Kosan Co

Inventors

• Sakanoue Shuichi
• Aoki Aya

Classifications

• C10N2040/08

  Hydraulic fluids, e.g. brake-fluids · CPC title

• C10N2030/08

  Resistance to extreme temperature · CPC title

• C10N2030/06

  Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure · CPC title

• C10M2215/28

  Amides; Imides · CPC title

• C10M169/04

  Mixtures of base-materials and additives · CPC title