NEW MATERIAL:The compound of formula I (R is hydrocarbon group; n is ≥4).

EXAMPLE: Pentadecalfluorothiol-octanoic acid myristyle ester.

USE: A lubricant exhibiting excellent lubrication effect even at a low temperature. It has rustproofing activity by sulfur atom introduced into the molecule. Suitable for lubrication of particular materials especially magnetic recording medium carrying ferromagnetic metal thin film, etc.

PREPARATION: The compound of formula I can be produced by reacting a perfluoroalkylcrboxylic acid chloride of formula II with nearly equimolar about of a mercaptan of formula R-SH in a solvent such as chloroform in the presence of a dehydrochlorination agent such as pyridine.