To produce a steel sheet by DR rolling while assuring lubricity in rolling and preventing the occurrence of mottling.
In the cold rolling after annealing, a solution having a cloudy point by dissolving a water-soluble lubricant is used as a coolant and the rolling is so performed that the coolant is supplied to the roll bite at liquid temperature above the cloudy point. The coolant supplied to the roll bite at the liquid temperature equal to or above the cloudy point has the remarkably improved adhesibility of the lubricant component to the steel sheet as compared to the case of the liquid temperature below the cloudy point and the lubricity equivalent to that of the coolant of the emulsion type is obtained. Even more, since the coolant is of the emulsion type, the occurrence of the mottling is prevented.
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