Novel ionic liquids

An ionic liquid of the general formula 1/n[Xn+][Y−] having a melting point of less than 100° C., where n is 1, 2 or 3 and

• the cation Xn+ is a cation selected from the group consisting of metal ions, quaternary ammonium, oxonium, sulfonium and phosphonium ions,
• the anion Y− has the general formula (II)
• R6O—(R7—O—)x—R8—COO− (II),
• where
• x is from 2 to 8,
• R6 is a branched on unbranched hydrocarbon group having from 1 to 3 carbon atoms,
• the radicals R7 are each, independently of one another, a branched or unbranched alkylenic group having from 2 to 4 carbon atoms and
• R8 is a branched or unbranched alkylenic group having from 1 to 4 carbon atoms,
• and the hydrogen atoms in the radicals R6, R7 and R8 can in each case be completely or partly replaced by fluorine.