Low ash lubricants with improved seal and corrosion performance

Patent metadata

Field	Value
Publication number	US-9399747-B2
Application number	US-201113698144-A
Country	US
Kind code	B2
Filing date	May 17, 2011
Priority date	May 20, 2010
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

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. 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) about 0.6 to about 6 percent by weight of a dispersant comprising the condensation product of a carboxylic functionalized polymer with an aromatic amine having at least 4 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;
wherein the total amount of neutral metal salt component in the lubricant composition is at least about 1.0 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 at least 4 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 aromatic amine comprises at least 4 aromatic groups and at least 2 secondary or tertiary amino groups.

6. The lubricant composition of claim 1 wherein the aromatic amine is represented by the structure

wherein independently each variable
R 1 and R 2 are hydrogen or C 1-5 alkyl groups;
U is an aliphatic, alicyclic, or aromatic group; and
w is zero to about 9.

7. The lubricant composition of claim 6 wherein, when U is an aliphatic group, U is an alkylene group containing 1 to about 5 carbon atoms.

8. The lubricant composition of claim 1 wherein the aromatic amine comprises material represented by the structure

9. 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.

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

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

12. A composition prepared by admixing the components of claim 1 .

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

14. The method of claim 13 wherein the internal combustion engine is a diesel engine.

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

Assignees

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

Inventors

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

Classifications

• C10N2020/04

  Molecular weight; Molecular weight distribution · CPC title

• C10M103/06

  Metal compounds · CPC title

• C10M133/12

  having amino groups bound to a carbon atom of a six-membered aromatic ring · CPC title

• C10M2217/06

  Macromolecular compounds obtained by functionalisation op polymers with a nitrogen containing compound · CPC title

• C10M2219/044

  Sulfonic acids, Derivatives thereof, e.g. neutral salts · CPC title