Patent ID: 8486292

Claim:
A magnetorheological formulation comprising: (a) an ionic liquid comprising anions and cations, and (b) dispersed magnetizable particles having a mean diameter of 0.1 to 500 μm; wherein the ionic liquid comprises one or more salts selected from the group consisting of 1-butyl-3-methylimidazolium methylsulfate, 1-ethyl-3-methylimidazolium ethylsulfate, 1-ethyl-3-methylimidazolium thiocyanate, 1-butyl-3-methylimidazolium thiocyanate, 1-ethyl-3-methylpyridinium ethylsulfate, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-methyl-3-octylimidazolium tetrafluoroborate, 1-methyl-3-octylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium hexafluorophosphate, 1-hexyl-3-methylimidazolium hexafluorophosphate, methyltrioctylammonium bis(trifluoromethylsulfonyl)imide, 1-ethyl-3-methylimidazolium 2-(2-methoxyethoxy)ethylsulfate and mixtures thereof, wherein said ionic liquids are still liquid at temperatures below −20° C.