Sulfonate detergent system for improved fuel economy

• US 20050065045A1
• Filed: 10/15/2002
• Published: 03/24/2005
• Est. Priority Date: 11/05/2001
• Status: Active Grant

• Current Assignee: The Lubrizol Corporation (Berkshire Hathaway Incorporated)
• Original Assignee: The Lubrizol Corporation (Berkshire Hathaway Incorporated)
• Inventors: Dohner, Brent R., Kelley, Jack C., Wilk, Melody A., Zalar, Frank V.
• Granted Patent: US 7,407,919 B2
• Time in Patent Office: Days
• US Class Current: 508/399
• CPC Class Codes: C10M 163/00 Lubricating compositions characterised by the additive being a mixture of a compound of unknown or incompletely defined constitution and a non-macromolecular compound, each of these compounds being essential
• CPC Class Codes: C10M 2207/026 with tertiary alkyl groups
• CPC Class Codes: C10M 2207/028 Overbased salts thereof
• CPC Class Codes: C10M 2207/26 Overbased carboxylic acid salts
• CPC Class Codes: C10M 2207/262 derived from hydroxy substituted aromatic acids, e.g. salicylates
• CPC Class Codes: C10M 2207/289 containing free hydroxy groups
• CPC Class Codes: C10M 2215/06 having amino groups bound to carbon atoms of six-membered aromatic rings
• CPC Class Codes: C10M 2215/064 Di- and triaryl amines
• CPC Class Codes: C10M 2215/28 Amides; Imides
• 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 2020/069 Linear chain compounds
• CPC Class Codes: C10N 2030/04 Detergent property or dispersant property
• CPC Class Codes: C10N 2030/06 Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure
• CPC Class Codes: C10N 2030/54 Fuel economy
• CPC Class Codes: C10N 2040/25 Internal-combustion engines

Abstract

A composition for lubricating an internal combustion engine includes an oil of lubricating viscosity; a predominantly linear alkylbenzenesulfonate detergent having a metal ratio of at least 8; and a combination of hindered phenolic ester antioxidant and aromatic amine antioxidant. The amount of any phenate detergent is less than 15% by weight of the total amount of detergents.

Claims

1. A composition suitable for lubricating an internal combustion engine, comprising:

(a) an oil of lubricating viscosity;

(b) an overbased detergent, wherein the detergent is exclusively or predominantly a linear alkylbenzenesulfonate detergent having a metal ratio of at least about 8, wherein in said composition the amount of phenate detergent is less than about 15% by weight of the total amount of detergents

(c) a combination of antioxidants comprising

(i) about 0.1 to about 2 weight percent hindered phenolic ester antioxidant and

(ii) about 0.2 to about 2 weight percent aromatic amine antioxidant; and

(d) at least one further component selected from the group consisting of dispersants, zinc dialkyldithiophosphates, and friction modifiers.

2. The composition of claim 1 wherein the detergent is exclusively or predominantly a calcium overbased synthetic linear alkylbenzenesulfonate detergent, the alkylbenzene group in said detergent having a number average molecular weight of about 320 to about 700.

3. The composition of claim 2 wherein the composition contains less than about 500 parts per million by weight of metals other than calcium or zinc.

4. The composition of claim 1 further comprising at least one salicylate detergent, saligenin detergent, or salixarate detergent.

5. The composition of claim 1 wherein the amount of any detergent other than the alkylbenzenesulfonate detergent is less than about 15% of the amount of the total amount of detergents.

6. The composition of claim 1 wherein the amount of any phenate detergent is less than about 1% by weight of the total amount of detergents.

7. The composition of claim 1 wherein the composition comprises a zinc dialkyldithiophosphate wherein said alkyl groups are predominantly secondary, in an amount to deliver about 0.025 to about 0.1 weight percent phosphorus to the composition.

8. The composition of claim 1 wherein the antioxidant component (c) further comprises about 0.1 to about 1 weight percent of a sulfurized olefin.

9. The composition of claim 8 wherein the sulfurized olefin is sulfurized 4-carbobutoxy cyclohexene.

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

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

12. A composition suitable for lubricating an internal combustion engine, comprising:

(a) an oil of lubricating viscosity;

(b) an overbased detergent, wherein the detergent is exclusively or predominantly a synthetic linear alkylbenzenesulfonate detergent having a metal ratio of at least about 8 and the alkylbenzene group therein having a number average molecular weight of about 320 to about 700, wherein in said composition the amount of phenate detergent is less than about 1% by weight of the total amount of detergents and the total amount of detergents other than the alkylbenzenesulfonate is less than about 15% by weight of the total amount of detergents;

(c) a combination of antioxidants comprising

(i) about 0.1 to about 2 weight percent hindered phenolic ester antioxidant,

(ii) about 0.2 to about 2 weight percent aromatic amine antioxidant, and

(iii) about 0.1 to about 1 weight percent of a sulfurized olefin antioxidant; and

(d) a zinc dialkyldithiophosphate wherein said alkyl groups are predominantly secondary, in an amount to deliver about 0.025 to about 0.1 weight percent phosphorus to the composition;

wherein the composition contains less than about 300 parts per million by weight of metals other than calcium or zinc.

13. A concentrate comprising

(a) a concentrate-forming amount of an oil of lubricating viscosity;

(b) an overbased detergent, wherein the detergent is exclusively or predominantly a linear alkylbenzenesulfonate detergent having a metal ratio of about at least about 8 and the alkylbenzene group therein having a number average molecular weight of about 320 to about 700, wherein in said composition the amount of phenate detergent is less than about 15% by weight of the total amount of detergents;

(c) a combination of antioxidants comprising

(i) hindered phenolic ester antioxidant and

(ii) aromatic amine antioxidant; and

(d) at least one further component selected from the group consisting of dispersants, zinc dialkyldithiophosphates, and friction modifiers.