Patent ID: 8586514

Claim:
A lubricant for use in processing of a high tensile strength steel sheet, consisting of: a lubricant base consisting essentially of hydrocarbons having a carbon number of 8-16 and a boiling point of 210° C. or less, and a modifier oil added to the lubricant base at a rate of 2-20 wt % of total weight of the lubricant, wherein the modifier oil contains (a) a sulfuric extreme pressure agent, (b) a rust inhibitive agent and (c) a calcium ingredient composed of highly-basic calcium sulfonates having base value of 300 mg KOH/g or more, wherein content of sulfur is 0.5-20 wt % of total weight of the modifier oil, wherein content of the rust inhibitive agent is 0.1-15 wt % of total weight of the modifier oil, wherein content of calcium is 0.1-15 wt % of total weight of the modifier oil, and wherein the lubricant has freezing point of not more than −40° C., kinetic viscosity of not greater than 12.5 mm 2 /s at −20° C., a flash point of 40° C. or more, and an ignition point of 240° C. or more, and wherein the rust inhibitive agent comprises at least one barium sulfonate, at least one oxidized wax compound, at least one calcium sulfonate, and at least one metallic soap of lanolin.