Lubricant fluids for the cold-rolling of steel, comprising one or more organic carbonates of general formula (I) RO- @-OR min (I) where R and R min , which can be identical or different, represent a C6-C30 linear or branched alkyl, cycloalkyl or cycloalkyl-alkyl radical, possibly mixed, in a quantity sufficient to provide the composition with the lubricant power necessary for the particular application, with a mineral oil base. These lubricant fluids can be conveniently used in the cold-rolling of any type of steel, either as whole oils or, after adding suitable quantities of emulsifiers, as oil concentrates for forming aqueous emulsions or microemulsions. In addition to possessing all the typical characteristics of rolling fluids, they are also able to minimize the formation of carbon residues and deposits in the subsequent annealing process.