| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject composition with suppressed discoloration, enabling e.g. its extent of deterioration to be accurately judged through visible inspection, by incorporating a base oil with a specific compound and an N-p- alkylphenyl-α-naphthylamine and/or a p, p'-dialkyl diphenylamine. SOLUTION: This lubricating oil composition is obtained by incorporating a base oil with (A) pref. 0.1-5 pts.wt., based on 100 pts.wt. of the base oil, of a compound of formula I (R<1> is an 8C or 13C branched alkyl) [e.g. 3-(3-methyl-5- tert-butyl-4-hydroxyphenyl)propionic acid 2-ethylhexyl ester ] and (B) pref. 0.1-5 pts.wt. of an N-p-alkylphenyl-α-naphthylamine of formula II (R<2> is a 1-16C alkyl) (pref. octylphenyl-α-naphthylamine) and/or a p,p'-dialky1 diphenylamine of formula III (R<3> and R<4> are each a 1-16C alkyl) (pref. dioctyl diphenylamine). |
