Lubricant composition

Patent metadata

Field	Value
Publication number	US-9850446-B2
Application number	US-201414892094-A
Country	US
Kind code	B2
Filing date	May 20, 2014
Priority date	May 20, 2013
Publication date	Dec 26, 2017
Grant date	Dec 26, 2017

Abstract

The lubricating oil composition according to the present invention is one including a base oil, (A) a substituted hydroxy aromatic carboxylic acid ester derivative represented by at least one of the general formula (I) and the general formula (II), and (B) a heterocyclic compound represented by the general formula (III) or (IV) blended therein, wherein a phosphorus content is 0.06 mass % or less on the basis of a total amount of the composition, and a sulfated ash content is 1.2 mass % or less on the basis of a total amount of the composition. The lubricating oil composition is capable of maintaining high-temperature detergency and acid neutralizing properties, even when amounts of a phosphorus component-containing additive and a metallic detergent are reduced.

First claim

The invention claimed is:

1. A lubricating oil composition comprising:
a base oil,
a substituted hydroxy aromatic carboxylic acid ester derivative represented by at least one of formula (I) and formula (II) in an amount of from 1 mass % to 7 mass % on the basis of a total amount of the composition, and
a heterocyclic compound represented by formula (III) or (IV) blended therein in an amount of from 0.05 mass % to 3 mass % on the basis of a total amount of the composition;
wherein:
a phosphorus content in the lubricating composition is 0.06 mass % or less on the basis of a total amount of the composition;
a sulfated ash content in the lubricating composition is 0.5 mass % or less on the basis of a total amount of the composition;

in formula I:
each of x and y is an integer satisfying 1≦x≦3 and 1≦y≦3, respectively,
each of R 1 and R 2 represents an alkyl group having 9 to 20 carbon atoms and may be the same as or different from each other, and
in the case of 2≦x≦3 and 2≦y≦3, plural R 1 s may be the same as or different from each other and plural R 2 s may be the same as or different from each other;

in the formula II:
each of m, n, o, and p is an integer satisfying 1≦m≦2, 0≦n≦2, 2≦(m+n)≦4, 1≦o≦3, and 1≦p≦3, respectively,
each of R 1 and R 2 represents an alkyl group having 9 to 20 carbon atoms and may be the same as or different from each other, and
in the case of 2≦o≦3 and 2≦p≦3, plural R 1 s may be the same as or different from each other and plural R 2 s may be the same as or different from each other; and

in formula (III) and formula (IV):
R 3 represents a linear or branched alkyl group having 7 to 17 carbon atoms,
n is 6 to 18,
each R 4 is independently selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 18 carbon atoms, a —COR 5 group, and an —OR 6 group,
R 5 is an alkyl group having 1 to 17 carbon atoms, and
R 6 is an alkyl group having 1 to 18 carbon atoms,
wherein the lubricating oil composition has a residual percentage of base number of from 36 to 47% determined as Residual percentage of base number (%)=[{Base number after the hot tube test (by the hydrochloric acid method)}/{Base number of new oil (by the hydrochloric acid method)}]×100.

2. The lubricating oil composition according to claim 1 , wherein in the lubricating oil composition:
the phosphorus content is 0.06 mass % or less on the basis of a total amount of the composition, and
the sulfated ash content is 0.3 mass % or less on the basis of a total amount of the composition.

3. The lubricating oil composition according to claim 1 , wherein in the lubricating oil composition:
the phosphorus content is 0.03 mass % or less.

4. The lubricating oil composition according to claim 1 , wherein in the lubricating oil composition:
the phosphorus content is 0.03 mass % or less, and
the sulfated ash content is 0.3 mass % or less on the basis of a total amount of the composition.

5. The lubricating oil composition according to claim 1 , further comprising at least one of an antioxidant and a dispersant.

6. The lubricating oil composition according to claim 1 , wherein in formula (III) or (IV), R 4 is a hydrogen atom or a methyl group.

7. The lubricating oil composition according to claim 6 , wherein in formula (III) or (IV), R 4 is a hydrogen atom.

8. A method for lubricating an internal combustion engine, comprising:
applying the lubricating oil composition according to claim 1 to the internal combustion engine.

9. The lubricating oil composition according to claim 1 , wherein each of R 1 and R 2 are each independently an alkyl group having 16 to 20 carbon atoms.

10. The lubricating oil composition according to claim 9 , wherein R 4 is a hydrogen atom or a methyl group and n is 8 to 18.

11. The lubricating oil composition according to claim 1 , wherein the substituted hydroxy aromatic carboxylic acid ester derivative is present in an amount of from 2 to 6 mass % based on the total mass of the composition.

12. The lubricating oil composition according to claim 1 , wherein the heterocyclic compound is present in an amount of from 0.1 to 2 mass % based on the total mass of the lubricating oil composition.

13. The lubricating oil composition according to claim 1 , wherein the heterocyclic compound is present in an amount of from 0.5 to 2 mass %.

14. The lubricating oil composition according to claim 1 , comprising a metallic detergent in an amount of 1.00 mass % or less and ZnDTP in an amount of 0.60 mass % or less.

15. The lubricating oil composition according to claim 1 , comprising the substituted hydroxy aromatic carboxylic acid ester derivative of formula (I) wherein R 1 and R 2 are, independently, an alkyl group having 16 to 20 carbon atoms, and the substituted hydroxy aromatic carboxylic acid ester derivative is present in an amount of from 5 to 7 mass % based on the total mass of the lubricating oil composition,
wherein the heterocyclic compound R 4 is a hydrogen atom or a methyl group and R 3 has 11 to 17 carbon atoms, and the heterocyclic compound is present in a total amount of from 0.050 to 1.00 mass % based on the total mass of the composition,
0.60 mass % or less of ZnDTP, and
1.00 mass % or less of metallic detergents, and
a phosphorous content of 0.04 mass % or less.

16. The lubricating oil composition according to claim 1 in the form of a diesel fuel, comprising hydro-refined mineral oil having a kinematic viscosity at 100° C. of 1.5 mm 2 /s-15 mm 2 /s and a viscosity index of 120 or more.

17. The lubricating oil composition according to claim 1 , wherein the base oil is a mineral oil.

Assignees

• Idemitsu Kosan Co

Inventors

• Iwasaki Junya
• Shimizu Yasunori

Classifications

• C10M129/72

  of polycarboxylic acids · CPC title

• C10M2207/028

  Overbased salts thereof · CPC title

• C10M2223/045

  Metal containing thio derivatives · CPC title

• C10M2203/1025

  used as base material · CPC title

• C10M2207/026

  with tertiary alkyl groups · CPC title