COLD ROLLING OIL AND COLD ROLLING METHOD

PROBLEM TO BE SOLVED: To provide an additive for cold rolling oil, in order to obtain cold rolling oil excellent in emulsion stability and lubricity in circulative use over long period of time, and contributing to improvement of surface quality of rolled materials and working environment.SOLUTION: This cold rolling oil for steel sheets comprises: at least one base oil selected from the group consisting of animal/vegetable oils and fats, mineral oils and synthetic esters; a nitrogen-containing water-soluble cyclic compounds; an oil-soluble aliphatic dicarboxylic acid or derivatives thereof; and a nonionic surfactant expressed by formula (a): R1-O-[(PO)(EO)(PO)]-R2, wherein R1 and R2 indicate fatty acid residue; PO indicates an oxypropylene group; EO indicates an oxyethylene group; x, y and z each denotes an average addition mole number and x+y is 3-30; z is 10-200; and PO and EO are added respectively in blocked form, and the molecular weight is 2,000 or more but less than 10,000.