Low foaming railway diesel engine lubricating oil compositions
AssigneeTexaco Inc.
InventorsBenjamin H. Zoleski, Frank J. Gaetani
Life of this patent
Estimating the term…
Abstract
A low foaming lubricating oil composition comprising a mineral oil, an oil soluble detergent-like additive which increases the foaming tendency of the lubricating oil, and an effective amount of an estolide of a hydroxy fatty acid having 10 to 24 carbon atoms which reduces the foaming tendency of the lubricating oil composition. The lubricating oil achieves the low foaming tendency without added silicone polymers and has a silicon content of less than about 10 parts per million by weight. The preferred estolide is the estolide of 12-hydroxystearic acid.
Claims18
In a railway diesel engine lubricant composition comprising a major amount of a mineral lubricating oil and, in an amount which tends to increase foaming, a metal detergent additive selected from the group consisting of overbased sulfurized calcium alkylphenolates and overbased alkaline earth metal sulfonates and which composition has a silicon content of less than about 10 parts per million by weight, the improvement comprising the composition containing in an amount to reduce foaming of an estolide of a hydroxy fatty acid having 10 to 24 carbon atoms.
In a railway diesel engine lubricant composition comprising a major amount of a mineral lubricating oil;
- in an amount which tends to increase foaming, a metal detergent additive selected from the group consisting of overbased sulfurized calcium alkylphenolates and overbased alkaline earth metal sulfonates;
- and at least one additive selected from the group consisting of a supplementary dispersant, a pour depressor and a silver friction modifier, and which composition has a silicon content of less than about 10 parts per million by weight, the improvement comprising the composition containing in an amount to reduce foaming of an estolide of a hydroxy fatty acid having 10 to 24 carbon atoms.
In a railway diesel engine lubricant concentrate composition comprising a minor amount of a mineral lubricating oil;
- in an amount which tends to increase foaming, a metal detergent additive selected from the group consisting of overbased sulfurized calcium alkylphenolates and overbased alkaline earth metal sulfonates;
- and at least one additive selected from the group consisting of a supplementary dispersant, a pour depressor and a silver friction modifier, and which composition has a silicon content of less than about 10 parts per million by weight, the improvement comprising the composition containing in an amount to reduce foaming of an estolide of a hydroxy fatty acid having 10 to 24 carbon atoms.
Dependencies are inferred from the claim text.