Method of lubricating a driveline device

Patent metadata

Field	Value
Publication number	US-9540582-B2
Application number	US-201213983913-A
Country	US
Kind code	B2
Filing date	Feb 15, 2012
Priority date	Feb 16, 2011
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

The invention provides a method of lubricating a mechanical device by supplying a lubricating composition containing an oil of lubricating viscosity and a compound having 2 to 20 hydroxy-carboxylic acid residues. The invention further relates to the use of the compound in a driveline device to provide at least one of antiwear performance, friction modification (particularly for enhancing fuel economy).

First claim

What is claimed is:

1. A method of lubricating a driveline device comprising supplying to the driveline device a lubricating composition comprising:
(a) an oil of lubricating viscosity and
(b) 0.01 wt % to 3 wt % of a compound having 2 to 20 repeat units of a residue of a hydroxy-carboxylic acid, wherein the compound is obtained/obtainable by a reacting a hydroxy-carboxylic acid with a hydrogen bonding donor capable of forming an ester or amide group with a carboxylic acid group of the hydroxy-carboxylic acid,

wherein the hydrogen bonding donor is selected from at least one member of the group consisting of an alcohol, a primary mono-amine and a secondary mono-amine,
wherein the hydroxy-carboxylic acid is a hydroxy-substituted carboxylic acid having 2 to 10 carbon atoms,
wherein, when the hydrogen bonding donor is a mono-ol, the mole ratio of mono-ol to the hydroxy-carboxylic acid ranges from 1:1.1 to 1:10, and
wherein the driveline device is an axle, a gearbox or a manual transmission.

2. The method of claim 1 , wherein the compound has 2 to 5 hydroxy-carboxylic acid residues.

3. The method of claim 1 , wherein the hydroxy-carboxylic acid is a hydroxy-substituted carboxylic acid having 2 to 3 carbon atoms.

4. The method of claim 1 , wherein the hydroxy-carboxylic acid is non-aromatic.

5. The method of claim 1 , wherein the hydroxy-carboxylic acid is aromatic.

6. The method of claim 1 , wherein the hydroxy-carboxylic acid has 1 to 6 hydroxyl groups.

7. The method of claim 1 , wherein the hydroxy-carboxylic acid contains two hydroxyl groups and two or three carboxylic acid moieties.

8. The method of claim 1 , wherein the hydroxy-carboxylic acid has two hydroxyl groups.

9. The method of claim 1 , wherein the hydroxy-carboxylic acid is selected from the group consisting of a glycolic acid, a malic acid, a salicylic acid, a mandelic acid, or a lactic acid, a tartaric acid, a citric acid, and mixtures thereof, and derivatives thereof.

10. The method of claim 1 , wherein the hydroxy-carboxylic acid is glycolic acid.

11. The method of claim 1 , wherein the hydroxy-carboxylic acid is tartaric acid.

12. The method of claim 1 , wherein the compound having 2 to 20 repeat units of a residue of a hydroxy-carboxylic acid is present 0.05 wt % to 0.8 wt % of the lubricating composition.

13. The method of claim 1 , wherein the lubricating composition further comprises at least one organo-sulphide selected from the group consisting of a polysulphide, a thiadiazole compound, or mixtures thereof.

14. The method of claim 13 , wherein the organo-sulphide is present in a range of 0.25 wt % to 6 wt %; of the lubricating composition.

15. The method of claim 1 , wherein the lubricating composition has a sulphur-content of 0.5 wt % to 3 wt % of the lubricating composition.

16. The method of claim 1 , wherein the manual transmission does contain a synchronizer system.

17. The method of claim 1 , wherein the manual transmission does not contain a synchronizer system.

18. The method of claim 1 , wherein the hydrogen bonding donor is a mono-alcohol.

19. The method of claim 18 , wherein the mole ratio of mono-ol to the hydroxy-carboxylic acid ranges from 1:1.1 to 1:5.

20. The method of claim 19 , wherein the mole ratio of mono-ol to the hydroxy-carboxylic acid ranges from 1:1.2 to 1:2.5.

Assignees

• Barton William R S
• Brown Gareth
• Baker Mark R
• Huston Michael E
• Lubrizol Corp

Inventors

• Barton William R S
• Brown Gareth
• Baker Mark R
• Huston Michael E

Classifications

• C10M2217/041

  involving a condensation reaction · CPC title

• C10N2040/04

  Oil-bath; Gear-boxes; Automatic transmissions; Traction drives · CPC title

• C10N2040/044

  for manual transmissions · CPC title

• C10M2207/289

  containing free hydroxy groups · CPC title

• C10M2209/102

  Polyesters · CPC title