Lubricating oil composition for engine made of aluminum alloy and lubrication method

Patent metadata

Field	Value
Publication number	US-9790450-B2
Application number	US-201314385874-A
Country	US
Kind code	B2
Filing date	Mar 12, 2013
Priority date	Mar 21, 2012
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

Lubricating oil compositions may include a base oil, a succinimide compound, and a thioheterocyclic compound. Such compositions may have a sulfur content of 0.10 mass % to 1.00 mass % based on a total amount of the composition. A phosphorus content represented by P in mass % and a sulfated ash content represented by M in mass %, based on the total amount of such compositions, may satisfy any of conditions A to C: condition A: P<0.03, and M<0.3; condition B: P<0.03 and 0.3≦M≦0.6; and condition C: 0.03≦P≦0.06 and M<0.3.

First claim

The invention claimed is:

1. A lubricating oil composition, comprising:
a base oil;
a first succinimide compound;
a second succinimide compound; and
a thioheterocyclic compound represented by formula (I):
(R 1 ) k —(S) m -A S -(S) n —(R 2 ) l   (I)

where
A S is a 1,3,4-thiadiazole ring;
(S) m and (S) n are bonded to the 1,3,4-thiadiazole ring at the 2-position and the 5-position, respectively;
each of R 1 and R 2 independently represents a hydrogen atom, an amino group, and a C1 to C50 group selected from the group consisting of an alkyl group, a cycloalkyl group, an alkenyl group, a cycloalkenyl group, and an aryl group, the C1 to C50 group optionally including at least one oxygen, nitrogen, or sulfur heteroatom;
each of k, l, m, and n is an integer of 1 to 5;
wherein:
the first succinimide compound comprises at least one of an alkenylsuccinimide and an alkylsuccinimide;
the second succinimide compound comprises at least one of a modified alkenylsuccinimide and a modified alkylsuccinimide;
the second succinimide compound is modified with at least one of a boron compound and an organic acid;
a boron content of the composition is 0.06 to 0.3 mass % based on a total mass of the composition;
a ratio by mass of boron to nitrogen (B/N) in the composition is 0.25 to 1.0;
a sulfur content of the composition is 0.10 mass % to 1.00 mass % based on a total mass of the composition; and
a phosphorus content represented by P in mass % and a sulfated ash content represented by M in mass %, based on the total mass of the composition, satisfy any of conditions A to C:
condition A: P<0.03, and M<0.3;
condition B: P<0.03, and 0.3≦M≦0.6; and
condition C: 0.03≦P≦0.06, and M<0.3.

2. The composition according to claim 1 , wherein a nitrogen content attributed to the succinimide compound is from 0.08 mass % to 0.40 mass %, based on the total mass of the composition.

3. The composition according to claim 2 , wherein the second succinimide compound is modified with a boron compound.

4. A method for lubricating an engine made of aluminum alloy, the method comprising:
applying, to a sliding part of the engine, the composition according to claim 1 ,
wherein the sliding part is made of aluminum alloy.

5. The composition according to claim 1 , wherein the thioheterocyclic compound is selected from the group consisting of 2,5-bis(t-nonylthio)-1,3,4-thiadiazole, 2,5-bis(dimethylhexylthio)-1,3,4-thiadiazole, 2,5-bis(octadecenylthio)-1,3,4-thiadiazole, 2,5-bis(methylhexadecenylthio)-1,3,4-thiadiazole, 2,5-bis(2-hydroxyoctadecylthio)-1,3,4-thiadiazole, 2,5-bis(n-octoxycarbonylmethylthio)-1,3,4-thiadiazole, 2,5-bis(dimethylhexyldithio)-1,3,4-thiadiazole, 2,5-bis(octadecenyldithio)-1,3,4-thiadiazole, 2,5-bis(methylhexadecenyldithio)-1,3,4-thiadiazole, 2,5-bis(2-hydroxyoctadecyldithio)-1,3,4-thiadiazole, and 2,5-bis(n-octoxycarbonylmethyldithio)-1,3,4-thiadiazole.

6. The composition according to claim 1 , further comprising 0.5 to 5 mass % of a metallic detergent.

7. The composition according to claim 1 , further comprising a phosphorus anti-wear agent.

8. The composition according to claim 1 , wherein a phosphorus content represented by P in mass % and a sulfated ash content represented by M in mass %, based on the total mass of the composition, satisfy condition A or B:
condition A: P<0.03, and M<0.3; and
condition B: P<0.03, and 0.3≦M≦0.6.

9. The composition according to claim 1 , wherein the thioheterocyclic compound comprises at least one of 2,5-bis(t-nonylthio)-1,3,4-thiadiazole, 2,5-bis(dimethylhexylthio)-1,3,4-thiadiazole, 2,5-bis(dimethylhexyldithio)-1,3,4-thiadiazole, and a compound of formula (1-b):

10. The composition according to claim 1 , wherein the thioheterocyclic compound comprises at least one of 2,5-bis(octadecenylthio)-1,3,4-thiadiazole, 2,5-bis(methylhexadecenylthio)-1,3,4-thiadiazole, 2,5-bis(2-hydroxyoctadecylthio)-1,3,4-thiadiazole, 2,5-bis(n-octoxycarbonylmethylthio)-1,3,4-thiadiazole, 2,5-bis(octadecenyldithio)-1,3,4-thiadiazole, 2,5-bis(methylhexadecenyldithio)-1,3,4-thiadiazole, 2,5-bis(2-hydroxyoctadecyldithio)-1,3,4-thiadiazole, 2,5-bis(n-octoxycarbonylmethyldithio)-1,3,4-thiadiazole, and a compound of formula (1-e):

Assignees

• Idemitsu Kosan Co

Inventors

• Iwasaki Junya
• Shimizu Yasunori
• Takashima Yoriyuki

Classifications

• C10M2215/064

  Di- and triaryl amines · CPC title

• C10M2203/1025

  used as base material · CPC title

• C10N2030/43

  Sulfur free or low sulfur content compositions · CPC title

• C10M161/00 Primary

  Lubricating compositions characterised by the additive being a mixture of a macromolecular compound and a non-macromolecular compound, each of these compounds being essential · CPC title

• C10M2207/026

  with tertiary alkyl groups · CPC title