Lubricating oil composition for shock absorber

Abstract

To provide a lubricating oil composition for a shock absorber for preventing wearing a piston rod and a guide bush in a shock absorber, which composition lowers the friction coefficient at the interface between bronze and chromium and reduces wear area of bronze. The lubricating oil composition for a shock absorber contains (A) a base oil composed of a mineral oil and/or a synthetic oil, and (B) a polyhydric alcohol partial ester having a C10 to C20 fatty acid residue, in an amount of 0.05 mass % to 10 mass %, with respect to the total amount of the composition.

1 . A lubricating oil composition for a shock absorber, comprising:
 (A) a base oil composed of a mineral oil and/or a synthetic oil, and;   (B) a polyhydric alcohol partial ester having a C10 to C20 fatty acid residue, in an amount of 0.05 mass % to 10 mass %, with respect to the total amount of the composition.   
     
     
         2 . A lubricating oil composition for a shock absorber according to  claim 1 , wherein the component (B) is a tetrahydric alcohol partial ester. 
     
     
         3 . A lubricating oil composition for a shock absorber according to  claim 1 , wherein the component (B) is pentaerythritol dioleate and/or pentaerythritol dilaurylate. 
     
     
         4 . A lubricating oil composition for a shock absorber according to  claim 1 , which further comprises (C) a phosphorus-containing compound.