Back to results
US 9,309,480 B2Granted
Lubricant composition comprising anti-foam agents
AssigneeThe Lubrizol Corporation
InventorsJohn G. Loop, William D. Abraham
Life of this patent
Estimating the term…
Abstract
The disclosed invention relates to a multigrade lubricant composition which can be used for numerous lubricant applications, but is particularly useful for lubricating a diesel engine. The lubricant composition comprises an oil of lubricating viscosity, a detergent, a dispersant, a viscosity index improver, and a combination of anti-foam agents. The lubricant composition may be used for providing enhanced fuel economy and avoiding air entrainment problems when used in lubricating diesel engines.
Claims17
A lubricant composition, comprising:
- an oil of lubricating viscosity;
- a detergent comprising an overbased calcium sulfonate, an overbased calcium phenate, or a mixture thereof;
- a dispersant;
- a zinc dialkyldithiophosphate;
- (1) about 5 to about 50 ppm of a first anti-foam agent comprising a polydimethyl siloxane having a kinetic viscosity (absent solvent) at 25° C. in the range from about 10,000 to about 50,000 mm2/s (cSt);
- (2) about 0.5 to about 13 ppm of a second anti-foam agent comprising a polydimethyl siloxane having a kinetic viscosity (absent solvent) at 25° C. in the range from about 80,000 to about 120,000 mm2/s (cSt);
- and
- (3) about 3.7 to about 35 ppm of a third anti-foam agent comprising a fluorinated polysiloxane having a kinematic viscosity (absent solvent) at 25° C. in the range from about 50 to about 500 mm2/s (cSt).
5 more elements
Dependencies are inferred from the claim text.