Patent ID: 8303850

Claim:
A rust preventive oil composition comprising: at least one base oil selected from the group consisting of mineral oils and synthetic oils, having a 5%-distillation temperature of not less than 140° C. and not more than 250° C., a 95%-distillation temperature of 250° C. or less, a difference between the 5%-distillation temperature and the 95%-distillation temperature of 90° C. or less, an aromatic content of 5% by volume or less, a naphthene content of not less than 30% by volume and not more than 95% by volume, a density at 15° C. of 0.75 g/cm 3 or more, and a kinematic viscosity at 40° C. of not less than 0.3 mm 2 /s and not more than 5.0 mm 2 /s; at least one base oil selected from the group consisting of mineral oils and synthetic oils, having a 5%-distillation temperature of 260° C. or more, and a kinematic viscosity at 40° C. of not less than 6.0 mm 2 /s and not more than 500 mm 2 /s; and a rust-preventing additive.