Lubricating oil compositions

• US 6,423,670 B2
• Filed: 03/14/2001
• Issued: 07/23/2002
• Est. Priority Date: 03/20/2000
• Status: Expired due to Term

• Current Assignee: Infineum International Limited (Infineum)
• Original Assignee: Infineum International Limited (Infineum)
• Inventors: MacDonald, Isabel P., Locke, Christopher J.
• Primary Examiner(s): Howard, Jacqueline V.
• Application Number:
  US09/808,081
• Publication Number:
  US 20010036906A1
• Time in Patent Office: 496 Days
• Field of Search: 508/192, 508/364, 508/398, 508/365, 508/372, 508/380, 508/586
• US Class Current: 508/192
• 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 2207/023 having hydroxy groups bound to carbon atoms of six-membered aromatic rings
• CPC Class Codes: C10M 2207/024 having at least two phenol groups but no condensed ring
• CPC Class Codes: C10M 2207/026 with tertiary alkyl groups
• CPC Class Codes: C10M 2207/027 Neutral salts thereof
• CPC Class Codes: C10M 2215/04 having amino groups bound to acyclic or cycloaliphatic carbon atoms
• CPC Class Codes: C10M 2215/086 Imides
• CPC Class Codes: C10M 2215/24 having hydrocarbon substituents containing thirty or more carbon atoms , e.g. nitrogen derivatives of substituted succinic acid
• CPC Class Codes: C10M 2215/26 Amines
• CPC Class Codes: C10M 2215/28 Amides; Imides
• CPC Class Codes: C10M 2217/042 between the nitrogen-containing monomer and an aldehyde or ketone
• CPC Class Codes: C10M 2217/043 Mannich bases
• CPC Class Codes: C10M 2217/046 Polyamines, i.e. macromoleculars obtained by condensation of more than eleven amine monomers
• CPC Class Codes: C10M 2217/06 Macromolecular compounds obtained by functionalisation op polymers with a nitrogen containing compound
• CPC Class Codes: C10M 2219/046 Overbasedsulfonic acid salts
• CPC Class Codes: C10M 2219/087 containing hydroxy groups; Derivatives thereof, e.g. sulfurised phenols
• CPC Class Codes: C10M 2219/088 Neutral salts
• CPC Class Codes: C10M 2219/089 Overbased salts
• CPC Class Codes: C10M 2223/045 Metal containing thio derivatives
• CPC Class Codes: C10M 2227/061 Esters derived from boron
• CPC Class Codes: C10N 2010/04 : Groups 2 or 12
• CPC Class Codes: C10N 2040/252 : Diesel engines
• CPC Class Codes: C10N 2040/253 : Small diesel engines

Abstract

A heavy duty diesel engine lubricating oil composition having no more than 0.10 wt. % phosphorus comprises an ashless dispersant, a neutral calcium phenate, an overbased calcium or magnesium sulfonate, a metal dihydrocarbyldithiophosphate, and a phenolic or aminic antioxidant.

Claims

1. A diesel engine lubricating oil composition comprising a major amount of oil of lubricating viscosity to which has been added:

(a) a lubricating oil ashless dispersant which has not more than 0.2 mass % boron;

(b) an oil-soluble neutral calcium phenate detergent;

(c) an oil-soluble overbased calcium or magnesium sulfonate or mixture thereof present in an amount such that not more than 0.05 magnesium is present in the composition;

(d) a metal dihydrocarbyldithiophosphate present in an amount such that the phosphorus content of the composition is from 0.025 to 0.10 mass %; and

(e) a phenolic or aminic antioxidant in a minor amount the composition being free of neutral metal detergent, other than the phenate (b).

2. The composition of claim 1 wherein the dispersant is a polyisobutenyl succinimide lubricating oil dispersant where the polyisobutenyl has an Mn of 1500 to 3000.

3. The composition of claim 1 wherein there is present 0.3 to 1.5 mass % of the neutral calcium phenate.

4. The composition of claim 1 wherein there is present 0.2 to 2 mass % of the overbased calcium or magnesium sulfonate or mixture thereof.

5. The composition of claim 1 wherein the metal dihydrocarbyldithiophosphate is a zinc dialkyldithiophosphate where the alkyl groups have 2 to 8 carbon atoms.

6. A method of lubricating a compression ignited engine which comprises supplying to the crankcase thereof a lubricating oil composition of claim 1.

8. The composition of claim 1, wherein antioxidant (e) is a hindered phenol.

9. The composition of claim 8 wherein there is present 0.1 to 1.5 mass % of antioxidant (e) in the form of a hindered phenol.

7. A concentrate for blending with an oil of lubricating viscosity to provide a diesel engine lubricating oil composition, said concentrate comprising:

(a) a lubricating oil ashless dispersant which has not more than 0.2 mass % boron;

(b) an oil-soluble neutral calcium phenate detergent;

(c) an oil-soluble overbased calcium or magnesium sulfonate or mixture thereof present in an amount such that not more than 0.3 mass % magnesium is present in the concentrate;

(d) a metal dihydrocarbyldithiophosphate present in an amount such that the phosphorus content of the concentrate is up to 0.7 mass %; and

(e) a phenolic or aminic antioxidant, the concentrate being free of neutral metal detergent, other than the phenate (b).