SALTS OF THIOPHOSPHORIC ACIDS AND THEIR USE IN LUBRICANTS

摘要

Salts composed of the anion of the di-, tri- or tetrathiophosphoric acid of formula (I) in which Z1 and Z2 independently of one another are an oxygen atom or a sulphur atom and Ra and Rb independently of one another are an organic group having 1 to 20 C atoms and a cation which comprises a heterocyclic ring system containing one to three nitrogen atoms.