Gear lubricant
AssigneeChevron U.S.A. Inc.
InventorEtho Satish Lalla
Life of this patent
Estimating the term…
Abstract
A gear oil composition is provided. The composition comprises a major amount of base oil comprising a mixture of a mineral base oil and polybutene; and 0.1 to 0.5 wt % of carbon black, based on the total weight of the gear oil composition. Such compositions can provide improved viscosity stability.
Claims12
A gear oil composition, comprising:
- a) a major amount of base oil comprising a mixture of a mineral base oil and polybutene present in an amount of greater than 10 wt %, based on the total weight of the gear oil composition;
- b) 0.1 to 0.5 wt % of carbon black, based on the total weight of the gear oil composition, wherein the carbon black consists of unit particles of amorphous carbon with the unit particles linking together into chains;
- c) 0.001 to 30 wt % of at least one additive selected from dispersants, detergents, antifoaming agents, antioxidants, rust inhibitors, metal passivators, extreme pressure agents, friction modifiers, and mixtures thereof, based on the total weight of the gear oil composition;
- and with the gear oil composition having a kinematic viscosity at 100° C. of from 10 mm2/s to 15 mm2/s.
A method for improving viscosity stability of a gear oil composition having a kinematic viscosity at 100° C. of from 10 mm2/s to 15 mm2/s comprising adding 0.1 to 0.5 wt % of carbon black, based on the total weight of the gear oil composition, to a major amount of base oil comprising a mixture of a mineral base oil and polybutene present in an amount of greater than 10 wt %, based on the total weight of the gear oil composition, wherein the carbon black consists of unit particles of amorphous carbon with the unit particles linking together into chains.
Dependencies are inferred from the claim text.