Grease composition, and method for lubricating sliding part using said grease composition

Abstract

An object of the invention is to provide a grease composition that does not deteriorate resin, particularly, acetal resin, in contact therewith even under a high temperature condition. The object can be attained by a grease composition for resin, including (A) a lubricating base oil, (B) a thickener, and (C) at least one selected from the group consisting of an organic molybdenum compound and a sulfur-based extreme pressure agent, wherein when the grease composition includes the sulfur-based extreme pressure agent, a content of the sulfur-based extreme pressure agent is from 0.05 mass % to 2.5 mass % based on a total amount of the composition, and the grease composition is substantially free of zinc dialkyldithiophosphate.

1 . A grease composition for resin, comprising
 (A) a lubricating base oil,   (B) a thickener, and   (C) at least one selected from the group consisting of an organic molybdenum compound and a sulfur-based extreme pressure agent, wherein   when the grease composition comprises the sulfur-based extreme pressure agent, a content of the sulfur-based extreme pressure agent is from 0.05 mass % to 2.5 mass % based on a total amount of the composition, and   the grease composition is substantially free of zinc dialkyldithiophosphate.   
     
     
         2 . The grease composition for resin according to  claim 1 , wherein the resin is acetal resin. 
     
     
         3 . The grease composition for resin according to  claim 1 , wherein the grease composition comprises the organic molybdenum compound, and a content of the organic molybdenum compound is from 0.05 mass % to 5 mass % based on the total amount of the composition. 
     
     
         4 . The grease composition for resin according to  claim 1 , wherein the grease composition comprises both the organic molybdenum compound and the sulfur-based extreme pressure agent. 
     
     
         5 . The grease composition for resin according to  claim 1 , wherein the thickener is a metal soap-based thickener. 
     
     
         6 . The grease composition for resin according to  claim 1 , wherein the grease composition has a penetration of from 265 to 475. 
     
     
         7 . The grease composition for resin according to  claim 1 , wherein
 (A) a content of the lubricating base oil is from 50 mass % to 95 mass % based on the total amount of the composition, and   (B) a content of the thickener is from 2 mass % to 30 mass % based on the total amount of the composition.   
     
     
         8 . The grease composition for resin according to  claim 1 , wherein a content of the zinc dialkyldithiophosphate is 1 mass % or less based on the total amount of the composition. 
     
     
         9 . The grease composition for resin according to  claim 2  for use in a member containing acetal resin and a metal. 
     
     
         10 . The grease composition for resin according to  claim 9 , wherein the metal is copper. 
     
     
         11 . A method for lubricating a sliding part, comprising allowing a grease composition according to  claim 1  to be disposed on the sliding part.