| 摘要 |
PROBLEM TO BE SOLVED: To obtain a lubricating oil compsn. which is highly oxidation-resistant and retains its excellent oxidation resistance even when long used at high temps. by compounding a lube base oil with a specific fatty acid ester and a specific nitrogen compd. in a specified ratio. SOLUTION: This compsn. is prepd. by compounding a lube base oil with 0.1-5.0 mass % (based on the compsn.; the same applies hereunder) 3-methyl-5- tert-butyl-4-hydroxyphenyl-substd. fatty acid ester represented by the formula (wherein R<1> is 1-6C alkylene; and R<2> is 1-24C alkyl or alkenyl) and 0.001-1.0 mass % at least one nitrogen compd. selected from among thiadiazole, benzotriazole and/or its deriv., and benzothiazole. |
