Lubricating oil composition for internal combustion engine

Patent metadata

Field	Value
Publication number	US-9938482-B2
Application number	US-201515113931-A
Country	US
Kind code	B2
Filing date	Jan 26, 2015
Priority date	Jan 27, 2014
Publication date	Apr 10, 2018
Grant date	Apr 10, 2018

Abstract

A lubricating oil composition for an internal combustion engine according to the present invention contains a lubricating base oil, (A1) a basic calcium salicylate having a TBN of 200 mgKOH/g or more, (A2) a basic sodium sulfonate having a TBN of 200 mgKOH/g or more and/or a basic calcium sulfonate having a TBN of 50 mgKOH/g or less, (B) a binuclear organic molybdenum compound and/or a trinuclear organic molybdenum compound, and (C) a polyalkyl (meth)acrylate having an SSI of 30 or less, a total content of molybdenum derived from the binuclear and trinuclear organic molybdenum compounds being 0.025 mass % or more relative to the whole amount of the composition and the lubricating oil composition having predetermined values of a high-temperature high-shear viscosity and a NOACK value (250° C., 1 hr).

First claim

The invention claimed is:

1. A lubricating oil composition for an internal combustion engine, the composition comprising a lubricating base oil and:
(A1) a basic calcium salicylate having a total base number, as measured by a perchloric acid method, of 200 mgKOH/g or more in an amount of from 1.0 mass % to 3.5 mass % relative to the whole amount of the composition;
(A2) a basic sodium sulfonate having a total base number, as measured by a perchloric acid method, of 300 mgKOH/g or more in an amount of from 0.1 mass % to 0.7 mass % relative to the whole amount of the composition and/or a basic calcium sulfonate having a total base number, as measured by a perchloric acid method, of 50 mgKOH/g or less in an amount of from 0.7 mass % to 3.0 mass % relative to the whole amount of the composition;
a total amount of component (A1) is greater than a total amount of component (A2);
the calcium content is regulated to 1,000 to 2.300 ppm on a mass basis in the lubricating oil composition;
wherein the sodium content is regulated to 200 to 800 ppm on a mass basis in the lubricating oil composition when the lubricating oil composition contains the basic sodium sulfonate; and
wherein a ratio of the calcium content to the sodium content (Ca/Na) is from 2.5 to 4 when the lubricating oil composition contains the basic sodium sulfonate;
(B) a binuclear organic molybdenum compound represented by the following general formula (I) and/or a trinuclear organic molybdenum compound represented by the following general formula (II):

and
wherein all organic molybdenum compounds are contained in an amount of 0.04 to 0.1 mass % in terms of a molybdenum content relative to the whole amount of the composition;
(C) a polyalkyl (meth)acrylate having an SSI of from 1 to 25,
wherein:
a total content of the polyalkyl (meth)acrylate (C) is from 2 to 20 mass % relative to the whole amount of the composition;
a total content of molybdenum derived from the binuclear and trinuclear organic molybdenum compounds is 0.025 mass % or more relative to the whole amount of the composition;
the lubricating oil composition has a high-temperature high-shear viscosity at 100° C. of 4.0 to 5.0 mPa·s, a high-temperature high-shear viscosity at 150° C. of 2.2 to 2.5 mPa·s, and a NOACK value (250° C., 1 hr) of 15 mass % or less;
each of R 1 to R 4 represents a hydrocarbon group having 4 to 22 carbon atoms, and R 1 to R 4 may be the same as or different from each other;
each of X 1 to X 4 represents a sulfur atom or an oxygen atom;
each of Ls independently represents a ligand having an organic group containing a carbon atom, and at least 21 carbon atoms are present in total in all the organic groups of the ligands;
n is 1 to 4;
k is 4 to 7;
Q represents a neutral electron donating compound; and
z is 0 to 5 and includes non-stoichiometric values.

2. The lubricating oil composition according to claim 1 , comprising at least the basic sodium sulfonate having a total base number, as measured by a perchloric acid method, of 300 mgKOH/g or more as the component (A2).

3. The lubricating oil composition according to claim 2 , further comprising the basic calcium sulfonate having a total base number, as measured by a perchloric acid method, of 50 mgKOH/g or less as the component (A2).

4. The lubricating oil composition according to claim 1 , further comprising a mononuclear organic molybdenum compound.

5. A method for producing a lubricating oil composition for an internal combustion engine, the method comprising blending:
(A1) a basic calcium salicylate having a total base number, as measured by a perchloric acid method, of 200 mgKOH/g or more in an amount of from 1.0 mass % to 3.5 mass % relative to the whole amount of the lubricating oil composition:
(A2) a basic sodium sulfonate having a total base number, as measured by a perchloric acid method, of 300 mgKOH/g or more in an amount of from 0.1 mass % to 0.7 mass % relative to the whole amount of the composition and/or a basic calcium sulfonate having a total base number, as measured by a perchloric acid method, of 50 mgKOH/g or less in an amount of from 0.7 mass % to 3.0 mass % relative to the whole amount of the composition;
B) a binuclear organic molybdenum compound represented by the following general formula (I) and/or a trinuclear organic molybdenum compound represented by the following general formula (II)):

and
wherein all organic molybdenum compounds are contained in an amount of 0.04 to 0.1 mass % in terms of a molybdenum content relative to the whole amount of the composition;
(C) a polyalkyl (meth)acrylate having an SSI of from 1 to 25,
wherein:
in the lubricating oil composition,
a total amount of component (A1) is greater than a total amount of component (A2);
the calcium content is regulated to 1,000 to 2,300 ppm on a mass basis in the lubricating oil composition;
wherein the sodium content is regulated to 200 to 800 ppm on a mass basis in the lubricating oil composition when the lubricating oil composition contains the basic sodium sulfonate; and
wherein a ratio of the calcium content to the sodium content (Ca/Na) is from 2.5 to 4 when the lubricating oil composition contains the basic sodium sulfonate; and
a total content of the polyalkyl (meth)acrylate (C) is from 2 to 20 mass % relative to the whole amount of the lubricating oil composition;
a total content of molybdenum derived from the binuclear and trinuclear organic molybdenum compounds is 0.025 mass % or more relative to the whole amount of the composition;
the lubricating oil composition has a high-temperature high-shear viscosity at 100° C. of 4.0 to 5.0 mPa·s, a high-temperature high-shear viscosity at 150° C. of 2.2 to 2.5 mPa·s er less, and a NOACK value (250° C., 1 hr) of 15 mass % or less;
each of R 1 to R 4 represents a hydrocarbon group having 4 to 22 carbon atoms, and R 1 to R 4 may be the same as or different from each other;
each of X 1 to X 4 represents a sulfur atom or an oxygen atom;
each of Ls independently represents a ligand having an organic group containing a carbon atom, and at least 21 carbon atoms are present in total in all the organic groups of the ligands;
n is 1 to 4;
k is 4 to 7;
Q represents a neutral electron donating compound; and
z is 0 to 5 and includes non-stoichiometric values.

6. A lubricating oil composition according to claim 1 , having a kinematic viscosity at 100° C. of 7.061 mm 2 /s or less.

7. The lubricating oil composition according to claim 1 , wherein the lubricating base oil has a viscosity index of 100 or more.

8. The lubricating oil composition according to claim 1 , wherein the basic calcium sulfonate has a total base number of 10 to 30 mgKOH/g.

9. The lubricating oil composition according to claim 1 , wherein R 1 to R 4 represent a hydrocarbon group having 4 to 18 carbon atoms.

10. The lubricating oil composition according to claim 1 , wherein X 1 to X 4 is an oxygen atom.

11. The lubricating oil composition for an internal combustion engine of claim 1 , wherein the basic calcium salicylate (A1) has a total base number, as measured by a perchloric acid method, of from 200 mgKOH/g to 500 mgKOH/g; and the basic sodium sulfonate (A2) has a total base number, as measured by a perchloric acid method, of 300 mgKOH/g to 500 mgKOH/g.

12. The method for producing a lubricating oil composition for an internal combustion engine according to claim 5 , having a kinematic viscosity at 100° C.

Assignees

• Idemitsu Kosan Co

Inventors

• Utaka Toshimasa

Classifications

• C10N2030/02

  Pour-point; Viscosity index · CPC title

• C10M2219/046

  Overbased sulfonic acid salts · CPC title

• C10N2030/68

  Shear stability · CPC title

• C10M2209/084

  Acrylate; Methacrylate · CPC title

• C10M2219/068

  Thiocarbamate metal salts · CPC title