| 摘要 |
PROBLEM TO BE SOLVED: To obtain a lubricating oil compsn. improved in utility value and heat, oxidation and abrasion resistances under severe conditions such as high- temp. conditions in particular by blending a specific base oil with a sulfur-contg. abrasion resistance improver. SOLUTION: 10-90wt.% organopolysiloxane of 2 to 25cSt in dynamic viscosity at 100 deg.C and of the general formula I (wherein R<1> to R<8> are each 1-8C alkyl, 6-18C aryl which may be substd. by 1-12C alkyl and is pref. phenyl; and x is 1 to 5), which is an organosilicon compd. polymer having a skeleton of siloxane bonds and having hydrocarbon groups each bonded directly to a silicon atom, is mixed with 90-10wt.% polyphenylthioether of the general formula II (wherein R<9> to R<11> are each H or a 1-24C hydrocarbon group; x, y and z are each 1 to 4; and m is 1 to 3) having aromatic rings each bonded to a sulfur atom at the m-position, and 0.1 to 7wt.% (based on the whole compsn.) dibenzyl sulfide compd. of the general formula III (wherein R<12> and R<13> are each a 1-10C hydrocarbon group; and n is 1 to 5) as a sulfur-contg. abrasion resistance improver to obtain a lubricating oil compsn. |
