Heat transfer fluids for low temperature application comprising aromatic hydrocarbons

Heat transfer fluid, for use over a broad range of temperatures, consisting essentially of a combination selected from:

• (a) a mixture of at least two structurally non-identical aromatic components selected from the group consisting of alkyl-benzene and polyalkyl-benzene wherein the alkyl moiety is represented by branched or straight carbon chains having from 1 to 6 carbon atoms provided that the total number of carbon atoms in the alkyl moiety(ies) is in the range of from 1 to 10;
• and
• (b) a mixture of an aromatic component selected from the group consisting of alkyl-benzene and polyalkyl-benzene wherein the alkyl moiety is represented by branched or straight carbon chains having from 1 to 6 carbon atoms provided that the total number of carbon atoms in the alkyl moiety(ies) is in the range of from 1 to 10 and an and aliphatic hydrocarbon having a linear or branched chain with from 5 to 15 carbon atoms, or mixtures thereof;
• at a level such that the composition has a cloud point below −100° C., preferably in the range of from −110° C. to −175° C., a vapor pressure at +175° C., below 827 kPa, and a viscosity, measured at the cloud point temperature of the fluid +10° C., below 400 cP.