| abstract |
The lubricating oil compsn. comprises (A) 0.05 to 5 wt.% of alkenylsuccinic acid ester and/or an alkylsuccinic acid ester, (B) 0.005 to 5 wt.% of a fatty acid ester of a polyhydric alcohol and (C) a base oil. The base oil (C) contains 0.5 wt.% or less sulphur component. The base oil (C) can be selected from among mineral oils such as 60 neutral oil, 100 neutral oil, 150 neutral oil, etc. or synthetic oils such as polyolefin, polyglycol ester, polyolester, phosphate ester, alkyl benzene ester. Specific examples of the alkenylsuccinic acid ester and/or alkylsuccinic acid ester (A) are octadecenylsuccinic acid dimethyl ester, octadecenylsuccinic acid dioctyl ester, octadecenylsuccinic acid dinoyl ester, hexadicynylsuccinic acid dimethyl ester etc. Specific examples of the fatty acid ester of a polyhydric alcohol (B) are obtd. from glycerin, trimethylpropane, pentaerythlit, solvit, etc. as polyalcohol and from laurinic acid, rhinolic acid, rinol acid, oleic acid, balminic acid, etc. as the fatty acid. |