Low ash lubricants with improved seal and corrosion performance

Patent metadata

Field	Value
Publication number	US-9719043-B2
Application number	US-201615213987-A
Country	US
Kind code	B2
Filing date	Jul 19, 2016
Priority date	May 20, 2010
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A lubricant composition of (a) an oil of lubricating viscosity; (b) a dispersant comprising the condensation product of a carboxylic functionalized polymer with an aromatic amine having at least 3 aromatic rings and at least one primary or secondary amino group; and (c) an overbased metal detergent comprising an oil-soluble neutral metal salt component and a metal carbonate component, provides good seal and corrosion performance. Desirably, the total amount of neutral metal salt component in the lubricant composition is at least about 0.75 percent by weight and the sulfated ash level of the lubricant composition is less than about 1.1 percent.

First claim

What is claimed is:

1. A lubricant composition comprising:
(a) an oil of lubricating viscosity;
(b) a dispersant comprising the condensation product of a carboxylic functionalized polymer with an aromatic amine having at least 3 aromatic rings and at least one primary or secondary amino group, said aromatic amine being an anthranilic derivative; and
(c) an overbased metal detergent comprising an oil-soluble neutral metal salt component and a metal carbonate component;
wherein the total amount of neutral metal salt component in the lubricant composition is at least about 0.75 percent by weight and wherein the sulfated ash level of the lubricant composition is less than about 1.1 percent.

2. The lubricant composition of claim 1 wherein the sulfated ash level of the lubricant is less than about 1.0 percent.

3. The lubricant composition of claim 1 wherein the carboxylic functionalized polymer comprises a polyisobutylene of number average molecular weight of about 500 to about 10,000 bearing at least one succinic anhydride group.

4. The lubricant composition of claim 1 wherein the dispersant comprises the condensation product of a carboxylic functionalized polymer with an aromatic amine having multiple aromatic groups, at least one secondary or tertiary amino group, and at least one nitrogen functional group which provides linkage to the carboxylic functionalized polymer.

5. The lubricant composition of claim 1 wherein the amount of the dispersant of (b) is about 0.6 to about 6 percent by weight.

6. The lubricant composition of claim 1 wherein the overbased metal detergent comprises an overbased, carbonated, calcium or magnesium sulfonate, phenate, salicylate, saligenin, or salixarate detergent.

7. The lubricant composition of claim 1 wherein the overbased metal detergent comprises an overbased carbonated magnesium saligenin detergent.

8. The lubricant composition of claim 1 wherein the amount of the overbased metal detergent is about 1.3 to about 5 percent by weight.

9. The lubricant composition of claim 1 wherein the total amount of neutral metal salt component in the lubricant composition is at least about 1.0 percent.

10. A lubricant composition prepared by admixing the components of claim 1 .

11. A method for lubricating an internal combustion engine, comprising supplying thereto the lubricant composition of claim 1 .

12. The method of claim 11 wherein the internal combustion engine is a diesel engine.

13. The method of claim 11 wherein the internal combustion engine is a heavy-duty diesel engine.

14. The lubricant composition of claim 1 wherein the aromatic amine having at least 3 aromatic rings and being an anthranilic derivative is represented by the formula

15. The lubricant composition of claim 1 wherein the dispersant is represented by the formula

where BB represents a polymer backbone and u is a number of 1 to about 2000.

16. The lubricant composition of claim 1 wherein the dispersant is represented by the formula

where PIB represents polyisobutylene.

Assignees

• Lubrizol Corp

Inventors

• Gieselman Matthew D
• Galic Raguz Mary
• Loop John G

Classifications

• C10M2205/00

  Organic macromolecular hydrocarbon compounds or fractions, whether or not modified by oxidation as ingredients in lubricant compositions · CPC title

• C10M165/00 Primary

  Lubricating compositions characterised by the additive being a mixture of a macromolecular compound and a compound of unknown or incompletely defined constitution, each of these compounds being essential · CPC title

• C10N2030/36

  Seal compatibility, e.g. with rubber · CPC title

• C10M2219/046

  Overbased sulfonic acid salts · CPC title

• C10N2040/255

  Gasoline engines · CPC title