DIALKYL POLYSULFIDE, PROCESS FOR PREPARING DIALKYL POLYSULFIDE, EXTREME-PRESSURE ADDITIVE AND LUBRICATING FLUID COMPOSITION

摘要

The purpose of the present invention is to provide a dialkyl polysulfide which can be added to a lubricating oil in a wide range of amounts and can effectively form a metal sulfide film on a metal surface and which is suitable for use as an extreme-pressure additive that is not susceptible of causing the corrosion of the metal surface. The present invention provides a dialkyl polysulfide which is represented by general formula (1) [wherein R1 and R2 represent alkyl groups respectively, and n is an integer of 1 to 6] and in which the sum of the content of a compound of general formula (1) wherein n is 2 and the content of a compound thereof wherein n is 3 is 80 to 100mass% relative to the total amount of the compounds of general formula (1).