Lubricant additive and lubricant composition

Abstract

A lubricating oil additive contains at least one steroid derivative selected from steroid saturated fatty acid ester, steroid carbonate ester and steroid ether. A lubricating oil composition added with the lubricating oil additive exhibits a low friction coefficient and excellent wear resistance, heat resistance and oxidation resistance stability.

1 . A lubricating oil additive, comprising at least one lanolin alcohol derivative selected from the group consisting of a lanolin-alcohol saturated fatty acid ester, a lanolin alcohol carbonate ester and a lanolin alcohol ether. 
   
   
       2 . A lubricating oil additive, comprising at least one steroid derivative selected from a steroid saturated fatty acid ester, a steroid carbonate ester and a steroid ether. 
   
   
       3 . The lubricating oil additive according to  claim 2 , wherein the steroid derivative is a cholesterol derivative. 
   
   
       4 . A lubricating oil composition, comprising: lubricating base oil; and the lubricating oil additive according to  claim 1 . 
   
   
       5 . The lubricating oil composition according to  claim 4 , further comprising at least one additive selected from the group consisting of viscosity index improvers, pour point depressants, antioxidants, ashless dispersants, friction modifiers, metal detergents, antiwear agents, rust inhibitors, metal deactivators, anti-emulsifiers and antifoaming agents. 
   
   
       6 . The lubricating oil composition according to  claim 4 , wherein the lubricating oil composition is used for engines, gears or industries. 
   
   
       7 . The lubricating oil composition according to  claim 5 , wherein the lubricating oil composition is used for engines, gears or industries. 
   
   
       8 . A lubricating oil composition, comprising: lubricating base oil; and the lubricating oil additive according to  claim 2 . 
   
   
       9 . The lubricating oil composition according to  claim 8 , further comprising at least one additive selected from the group consisting of viscosity index improvers, pour point depressants, antioxidants, ashless dispersants, friction modifiers, metal detergents, antiwear agents, rust inhibitors, metal deactivators, anti-emulsifiers and antifoaming agents. 
   
   
       10 . The lubricating oil composition according  claim 8 , wherein the lubricating oil composition is used for engines, gears or industries. 
   
   
       11 . The lubricating oil composition according  claim 9 , wherein the lubricating oil composition is used for engines, gears or industries.