HYDRAULIC FLUID COMPOSITION FOR SHOCK ABSORBER

摘要

PROBLEM TO BE SOLVED: To provide a hydraulic fluid composition for a shock absorber that can reduce friction force at a sliding part of a shock absorber, especially can reduce a friction force between a piston equipped with a fluororesin-based sliding material and a cylinder, and can keep its characteristics for a long period of time. SOLUTION: The hydraulic fluid composition for shock absorbers comprises a lubricating base oil comprised of (A) at least one sort selected from a phosphorous or phosphoric ester having an 11-30C alkyl or alkenyl group and a phosphorous or phosphoric ester amine salt having the alkyl or alkenyl group and (B) a 6-30C saturated or unsaturated fatty acid glycerol ester whose triester content based on the sum of the esters is not more than 10 mass% and the mass ratio of a monoester against the sum of mono- and di-ester is at least 0.5. COPYRIGHT: (C)2007,JPO&INPIT