| 摘要 |
PROBLEM TO BE SOLVED: To provide an excellently safe process oil exhibiting characteristics comparable to those of a conventional aromatic oil without causing problems of carcinogenicity and to provide a simple method for producing the process oil. SOLUTION: The process oil is obtained by mixing an extract prepared by deasphalting and solvent extraction of a vacuum distillation residue of crude oil with a lubricating base oil having <3 mass% of content of a PCA (polycyclic aromatic hydrocarbon) and has the following properties (a) to (g). (a) <3 mass% content of the PCA, (b) 30-80 mm<SP>2</SP>/s viscosity (100°C), (c)≤90°C aniline point, (d)≥240°C flash point, (e)≤1 mass ppm of benzo(a)pyrene, (f)≤10 mass ppm content of a specific aromatic compound and (g) 10-30 mass% content of a polar substance. COPYRIGHT: (C)2007,JPO&INPIT |
