Patent ID: 8173582

Claim:
An oil composition for cutting and grinding by minimum quantity lubrication system, comprising: a complete ester oil of a polyhydric alcohol and a monobasic acid with a kinematic viscosity of 1.8-9.8 mm 2 /s at 100° C., and an ester-based polymer with a kinematic viscosity of 400 mm 2 /s to 2,500 mm 2 /s at 100° C. and an average molecular weight of 50,000 to 500,000; wherein the content of the complete ester oil is 90.0% by mass to 99.99% by mass based on the total amount of the oil composition; wherein the content of the ester-based polymer is 0.01% by mass to 5% by mass based on the total amount of the oil composition, and wherein the ester-based polymer is a polymethacrylate.