A lubricating composition is provided comprising a polyol ester which is the reaction product of a neopolyol with linear or branched monocarboxylic acids and mixtures thereof having from 1 to about 25 carbon atoms and a natural or GTL oil of lubricating viscosity and mixtures thereof and wherein the weight ratio of the ester to oil will be sufficient to provide a composition having a viscosity less than the individual viscosities of the ester and oil.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1 to 10 are graphs of the experimental data illustrating the invention.
Claims
1. A lubricating composition comprising:
a polyol ester which is the reaction product of a neopolyol with linear or branched monocarboxylic acids, and mixtures thereof having from 1 to about 25 carbon atoms and a natural or GTL oil of lubricating viscosity and mixtures thereof;the weight ratio of ester to oil being a ratio sufficient to provide a composition having a kinematic viscosity at 100° C. that is less than the kinematic viscosity at 100° C. of each of the oil and ester.
2. The composition of claim 1 wherein the ester has from 0 up to about 1 free hydroxyl groups.
3. The composition of claim 1 wherein the weight ratio of ester to natural or GTL ratio is between 20:80 to 80:20.
4. The composition of claim 2 wherein the neopolyol is selected from the group consisting of neopentylglycol, trimethylolpropane, monopentaerythritol, technical grade pentaerythritol, and dipentaerythritol.
5. The composition of claim 4 wherein the monocarboxylic acid is a mixture of acids.
6. The composition of claim 5 wherein the natural oil of lubricating viscosity is a mineral oil.
7. The composition of claim 6 wherein the ester and mineral oil have substantially the same kinematic viscosity at 100° C.
8. The composition of claim 7 wherein the mineral oil is a blend of mineral oils.
9. The composition of claim 1 wherein the oil of lubricating viscosity is a GTL oil.
10. The composition of claim 9 wherein the polyol ester has substantially no free hydroxyl groups.
11. The composition of claim 9 wherein the neopolyol is pentaerythritol, and the monocarboxylic acids are a mixture of acids.
12. The composition of claim 1, 8, and 11 including at least one additive selected from the group consisting of antioxidants, dispersants, detergents, antiwear agents, pour point depressants, friction modifiers, viscosity modifiers and antifoamants.
13. A method for improving the efficiency of an internal combustion engine lubricated with a lubricating oil composition comprising a natural or GTL base oil, the method comprising providing the base oil with a polyol ester of a neopolyol with linear or branched monocarboxylic acids and mixtures thereof having from 1 to about 25 carbon atoms in an amount sufficient to provide a composition having a kinematic viscosity at 100° C. that is less than the kinematic viscosity at 100° C. of each of the oil and ester.
14. The method of claim 13 wherein the ester has from 0 up to about 1 free hydroxyl group per molecule.
15. The method of claim 14 wherein the oil is a natural mineral oil.
16. The method of claim 14 wherein the oil is a GTL oil.
Patent Application
20070232506
