Abstract SULFUR CONTAINING PHOSPHATE ESTERS OF THIO ESTERS OF PHENOLS AND ALKOXYLATED PHENOLS ARE DESCRIBED, TOGETHER WITH METHODS FOR THEIIR PREPARATION AND THEIR USE AS LUBRICANTS. THE SULFUR CONTAINING PHOSPHATE ESTERS DEDCRIBED ARE REPRESENTED BY THE GENERAL FORMULA: ((Z,(R-S-)X-PHENYL)-(O-CH(-Y)-CH2)N-O)M-P(=O)-(O-M)(3-M) WHEREIN: R IS AN ALKYL GROUP OF 1-20 CARBON ATOMS, PHENYL OR ARALKYL X IS AN INTEGER OF FROM 1 TO 3 INCLUSIVE N IS AN INTEGER OF FROM 0 TO 50 INCLUSIVE (PREFERABLY 1-20) M IS AN INTEGER OF 1 TO 3 INCLUSIVE Y IS HYDROGEN, NETHYL OR ETHYL Z IS HYDROGEN OR ALKYL, OF 1 TO 20 CARBONS ATOMS AND M IS A CATION, E.G. H, ALKALI METAL, ALKALINE EARTH METAL, HEAVY METAL, AMMONIUM OR AMINO. THESE SULFUR CONTAINING PHOSPHATE ESTERS HAVE VALUABLE LUBRICATING PROPERTIES AND EXHIBIT GOOD ANTI-WEAR EXTREME PRESSURE PROPERTIED BOTH ALONE OR IN WATER OR AS ADDITIVES TO OTHER LUBRICANTS, SUCH AS MINERAL OILS, EXPECIALLY FOR USE AS CUTTING OILS OR OTHER METAL WORKING APPLICATIONS, GEAR LUBRICANTS, ECT.