LUBRICATING OIL COMPOSITION FOR CRANKCASE APPLICATIONS

• US 20110067662A1
• Filed: 09/22/2009
• Published: 03/24/2011
• Est. Priority Date: 09/22/2009
• Status: Active Grant

• Current Assignee: Afton Chemical Corporation
• Original Assignee: Afton Chemical Corporation
• Inventors: LOPER, John T.
• Granted Patent: US 8,207,099 B2
• Time in Patent Office: Days
• US Class Current: 123/1.A
• CPC Class Codes: C10M 167/00 Lubricating compositions characterised by the additive being a mixture of a macromolecular compound, a non-macromolecular compound and a compound of unknown or incompletely defined constitution, each of these compounds being essential
• CPC Class Codes: C10M 2207/281 of (cyclo)aliphatic monocarboxylic acids
• CPC Class Codes: C10M 2207/282 of (cyclo)aliphatic oolycarboxylic acids
• CPC Class Codes: C10M 2207/283 of polyhydroxy compounds
• CPC Class Codes: C10M 2209/102 Polyesters
• CPC Class Codes: C10M 2209/104 of alkylene oxides containing two carbon atoms only
• CPC Class Codes: C10M 2209/105 of alkylene oxides containing three carbon atoms only
• CPC Class Codes: C10M 2209/106 of alkylene oxides containing four carbon atoms only
• CPC Class Codes: C10M 2219/046 Overbasedsulfonic acid salts
• CPC Class Codes: C10M 2223/045 Metal containing thio derivatives
• CPC Class Codes: C10N 2010/04 Groups 2 or 12
• CPC Class Codes: C10N 2020/04 Molecular weight; Molecular weight distribution
• CPC Class Codes: C10N 2030/24 Emulsion properties
• CPC Class Codes: C10N 2040/25 Internal-combustion engines

Abstract

A crankcase lubricant, an additive concentrate and a method for improving water tolerance of a lubricant. The lubricant includes a) a major amount of a base oil; b) an alkali or alkaline earth metal-containing detergent; c) a phosphorus-based wear preventative; and d) a surfactant agent other than (b). The lubricant has a weight ratio of alkali or alkaline earth metal content to phosphorus content, based on a total mass of lubricant, ranging from about 1.6 to about 5.0.

Claims

1. A crankcase lubricant, comprising:

a) a major amount of a base oil;

b) an alkali or alkaline earth metal-containing detergent;

c) a phosphorus-based wear preventative; and

d) a surfactant agent other than (b),

wherein the lubricant has a weight ratio of alkali or alkaline earth metal content to phosphorus content, based on a total mass of lubricant, ranging from about 1.6 to about 5.0.

2. The crankcase lubricant according to claim 1, wherein the phosphorus-based wear preventative comprises at least one zinc dihydrocarbyl dithiophosphate compound.

3. The crankcase lubricant according to claim 1, further comprising a metal free friction modifier.

4. The crankcase lubricant according to claim 3, wherein the metal free friction modifier comprises a monoester of a C₅ to C₃₀ carboxylic acid.

5. The crankcase lubricant according to claim 4, wherein the lubricant comprises more than about 0.10 weight percent of the monoester based on a total weight of the lubricant composition.

6. The crankcase lubricant according to claim 1, wherein the surfactant agent comprises a block or graft co-polymer of the general formula (A-COO)_mB, where m in an integer of at least 2 and, A is a polymeric component having a molecular weight of at least 500 and is the residue of an oil-soluble complex mono-carboxylic acid of the general structural formula:

7. The crankcase lubricant according to claim 2, wherein the composition contains from about 200 to about 1000 ppm phosphorus from the zinc dihydrocarbyl dithiophosphate compound.

8. The crankcase lubricant according to claim 7, wherein the composition contains from about 300 to 800 ppm phosphorus from the zinc dihydrocarbyl dithiophosphate compound.

9. The crankcase lubricant according to claim 1, wherein the composition contains from about 1000 ppm to about 3000 ppm metal from the metal-containing detergent.

10. The crankcase lubricant according to claim 1, further comprising at least one component selected from the group consisting of:

an extreme pressure agent, an antiwear agent, a friction modifier, a dispersant, a defoamant, and an antioxidant,

11. The crankcase lubricant according to claim 1, wherein the surfactant has an HLB value ranging from about 4 to about 5.

12. An internal combustion engine lubricated with the composition according to claim 1.

13. An additive composition suitable for use in a crankcase lubricant, comprising:

a) an alkali or alkaline earth metal-containing detergent;

b) a phosphorus-based wear preventative;

c) a surfactant agent other than (a); and

d) a non-metal friction modifier,

wherein the additive composition has a weight ratio of alkali or alkaline earth metal content to phosphorus content ranging from about 1.6 to about 5.0.

14. The additive composition according to claim 13, wherein the metal detergent is an overbased calcium sulfonate.

15. The additive composition according to claim 13, wherein the phosphorus-based wear preventative comprises at least one zinc dihydrocarbyl dithiophosphate compound.

16. The additive composition according to claim 13, wherein the surfactant agent comprises a block or graft co-polymer of the general formula (A-COO)_mB, where m in an integer of at least 2 and, A is a polymeric component having a molecular weight of at least 500 and is the residue of an oil-soluble complex mono-carboxylic acid of the general structural formula:

17. The additive composition according to claim 13, further comprising at least one component selected from the group consisting of:

an extreme pressure agent, an antiwear agent, a friction modifier, a dispersant, a defoamant, and an antioxidant.

18. A method for improving the water tolerance of a crankcase lubricant containing more than about 0.1 percent by weight of a non-metal friction modifier, comprising combining a major amount of a base oil with an alkali or alkaline earth metal-containing detergent, a phosphorus-based wear preventative, and a surfactant agent having an HLB value ranging from about 4 to about 5.

19. The method of claim 18 wherein the lubricant has a weight ratio of alkali and/or alkaline earth metal content to phosphorus content, based on total mass of the lubricant, ranging from about 1.6 to about 5.0.

20. The method of claim 18, wherein the surfactant is derived from polystearic acid and polyglycols.

21. The method of claim 18, wherein the lubricant passes an E85 engine emulsion test.

22. The method claim 18, wherein the non-metal friction modifier comprises a monoester of a C₅ to C₃₀ carboxylic acid.

23. The method of claim 18, wherein the lubricant comprises from about 0.10 to about 0.5 weight percent of the monoester based on a total weight of the lubricant composition.