Lubricating composition having improved storage stability
AssigneeChevron U.S.A. Inc.
InventorsJohn A. Zakarian, Michael J. Haire
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Abstract
A lubricating oil composition having superior storage stability and load-carrying effect is disclosed. The composition comprises four components: (1) an alkali metal borate; (2) an oil-soluble sulfur compound; (3) a trialkyl hydrogen phosphite; and (4) a mixture of greater than 50% neutralized acidic phosphates that are essentially free of monothiophosphates.
Claims16
A lubricating composition having enhanced storage stability and load-carrying properties, said composition comprising an oil of lubricating viscosity wherein a minor amount of a mixture of the following components is dispersed:
- (a) a hydrated alkali metal borate component;
- (b) an oil-soluble sulfur-containing compound component;
- (c) a trialkyl phosphite component, at least 90 wt. % of which has the formula (RO)3P, where R is alkyl of 4 to 24 carbon atoms;
- and
- (d) a mixture of neutralized phosphates component, said phosphates being essentially free of monothiophosphates, wherein the components of said mixture react synergistically to enhance the load carrying properties and storage stability of the lubricant composition.
A lubricating oil concentrate having enhanced storage stability, said concentrate comprising a mixture of:
- (a) a hydrated alkali metal borate component;
- (b) an oil-soluble sulfur-containing compound component;
- (c) a trialkyl phosphite component, at least 90 wt. % of which has the formula (RO)3P, where R is alkyl of 4 to 24 carbon atoms;
- and
- (d) a mixture of neutralized phosphates component, said phosphates being essentially free of monothiophosphates, wherein the components of said mixture react synergistically to enhance load carrying properties and storage stability when blended with a lubricating base oil to create a lubricant composition.
A process for the preparation of a lubricant composition having enhanced storage stability and load carrying properties, wherein a minor but effective amount of a lubricating oil concentrate comprising a mixture of:
- (a) a hydrated alkali metal borate component:
- (b) an oil-soluble sulfur-containing compound component;
- (c) a trialkyl phosphate component, at least 90 wt. % of which has the formula (RO)3P, where R is alkyl of 4 to 24 carbon atoms, and
- (d) a mixture of neutralized phosphates component, said phosphates being essentially free of monothiophosphates, is blended with a major amount of a lubricating base oil, the components of said mixture reacting synergistically to enhance load carrying properties.
A lubricating composition with enhanced storage stability comprising:
- (a) a major amount of a base oil of lubricating viscosity:
- and
- (b) a minor amount of an additive concentrate comprising:
- (i) alkali metal triborate dispersion
- (ii) alkyl polysulfide
- (iii) neutral phosphate,
- (iv) trialkyl phosphite.
Dependencies are inferred from the claim text.