Solid anti-friction devices – materials therefor – lubricant or se – Lubricants or separants for moving solid surfaces and... – Heterocyclic ring compound; a heterocyclic ring is one...
Patent
1996-04-24
1998-04-07
Howard, Jacqueline V.
Solid anti-friction devices, materials therefor, lubricant or se
Lubricants or separants for moving solid surfaces and...
Heterocyclic ring compound; a heterocyclic ring is one...
508333, 508353, 508433, 508443, 508584, 508572, 508591, C10M16904
Patent
active
057364907
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to automotive lubricant compositions based on white oil, and especially to automotive lubricants such as engine oils, gear oils and automatic transmission fluids.
Traditionally automotive lubricants have been based on conventional mineral oils. Whilst these have proved adequate in the past, mineral off basestocks cannot always meet the increasing demands for superior lubricant properties, especially operational lifetime. These improved properties can be achieved to some extent by the use of additives, but research has also been conducted into modifying or changing the basestocks. In recent years lubricant manufacturers have produced automotive lubricants based on synthetic basestocks, for example polyalphaolefins and esters. Whilst these provide improved performance, they have the disadvantage that they are expensive.
There is therefore a need for an automotive lubricant with an alternative, less expensive basestock which provides improved properties.
International application WO 93/16151 describes an automotive lubricant composition comprising a basestock of which at least 30 wt. % is a white oil basestock and at least one antioxidant additive. Other, conventional, lubricant additives may also be included. This white oil-based lubricant has the advantage that it exhibits better oxidation stability than comparative mineral-based lubricants, but is less expensive than comparative synthetic-based lubricants.
The present invention relates to a further improvement in the oxidation stability of white oil-based automotive lubricants.
In one aspect, the present invention provides an automotive lubricant composition comprising a white oil-containing basestock and at least one polyisoalkylene compound.
In another aspect, the present invention provides a method of providing or enhancing protection against oxidation of a lubricating oil (e.g., a white oil-containing lubricating oil) by adding to, or incorporating in, the lubricating oil, at least one polyisoalkylene compound.
In another aspect, the invention provides a method of operating automotive equipment selected from one or more items chosen from an internal combustion engine, a gearbox, an automatic transmission, the method comprising lubricating the said equipment with an automotive lubricating composition comprising a white-oil containing basestock and at least one polyisoalkylene compound.
Polyisoalkylenes such as polyisobutylene are known for use as thickeners to increase the viscosity of lubricants based on conventionally refined mineral oils. We have found, surprisingly, that when polyisoalkylene is added to a white oil-based lubricant it has the effect of improving its oxidation stability so that the resulting polyisoalkylene-containing white oil-based lubricant can be employed as an automotive lubricant. Polyisoalkylenes have not previously been proposed or used as anti-oxidants. Thus the resulting automotive lubricant of the invention has the benefit of increased efficacious operation times, i.e. it can be used to lubricate an automotive mechanical device, for example an internal combustion engine or gear box or automotive transmission for an extended period before it requires replacing. In some applications the lubricant can be used as a fill-for-life lubricant, i.e. the operational life-time of the lubricant matches or exceeds that of the mechanical part it is lubricating.
The white oil used as the base oil for the lubricant of the present invention may be a white oil obtained by solvent extraction of a lubricant basestock feed and hydrogenation of the resulting raffinate in one or more hydrogenation stages to produce a white oil lubricant basestock which is virtually free of sulphur and nitrogen. White oils are defined in the "Food and Drug Adminstration Code of Federal Regulation", 1991. Either medicinal white oils according to specification FDA 21 CFR 178-3620 (a) or technical white oils according to specification FDA CFR 178-3620 (b) may be employed in the present invention.
Preferably the white oil is highly naphth
REFERENCES:
patent: 2335331 (1943-11-01), Wright et al.
patent: 4062785 (1977-12-01), Nibert
patent: 4098703 (1978-07-01), Crossfield et al.
patent: 5321172 (1994-06-01), Alexander et al.
Bouffet Alain Gabriel
Ostyn Marcel Alphonse
Allocca Joseph J.
Exxon Research and Engineering Company
Howard Jacqueline V.
Watts Susan Fletcher
LandOfFree
Automotive white-oil based lubricant composition does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Automotive white-oil based lubricant composition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automotive white-oil based lubricant composition will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-13273