[0039] The larger number n functions for decrease in a viscosity more effectively, but the number n exceeding 20 is not preferred because an effect on basicity and dielectric constant derived from the aromatic ring moiety Ry contain› ing basic functional group explained infra is lowered. 

[0040] The effect on basicity and dielectric constant which is derived from Ry of the compound of the present invention is important for applications to an ionic liquid, actuator and electrolyte for solar cell explained infra. In those cases, the number n of repeated fluorine-containing ether units is preferably from 1 to 15, further preferably from 1 to 12. 

[0041] For example, for removing an acid from waste water, there is a case where an anionic polymer is used as an acid-removing agent from the viewpoint of easy separation from water and easy recycling. However since an acid› removing process is a liquid-solid reaction, an acid-remov› ing efficiency cannot always be said to be good. The compound of the present invention containing a fluorine› containing ether is a liquid, and therefore an acid-removing process is a liquid-liquid reaction which is high in efficiency. But in the case of a short fluorine-containing ether chain, there is a case where the compound is dissolved in the acidic aqueous solution and separation thereof becomes difficult. From this point of view, a longer fluorine-containing ether chain is preferred. 

[0042] Therefore in the case of applications to materials such as an acid-removing agent and lubricant, in which the features of the fluorine-containing ether unit are utilized, the larger the number n of repeated fluorine-containing ether units, the more preferable, namely the number of repeat units is from 5 to 20, more preferably from 10 to 20. 

[0043] The second feature of the aromatic compound of the formula (1) used for the ionic liquid type functional material of the present invention is that the moiety Ry containing the basic functional group and having an aro› matic ring structure is bonded to the fluorine-containing ether moiety -D-. To Ry is bonded at least one moiety containing the fluorine-containing ether -D-, and 2 to 4 moieties may be bonded to Ry. 

[0044] Ry is a mono-, di-, tri- or tetra-valent organic group having 2 to 30 carbon atoms which has at least one selected from the basic functional groups Y $^{1 }$and/or the salts Y $^{2 }$of the basic functional groups and contains an aromatic ring struc› ture. 

[0045] The basic functional group Y 1 in Ry may be selected from functional groups having a pKa value larger than that of water, and is usually selected from functional groups having a pKa value of not less than 20. The pKa value is preferably not less than 20, more preferably not less than 25, particularly preferably not less than 28. 

[0046] A too low basicity (a too low pKa value) is not preferred because an ionic function as an ionic liquid is not exhibited sufficiently when forming into a salt by reaction with an acid. 

[0047] For example, when the compound is used as a reaction medium or as a part thereof, dissolution of a targeted reaction compound becomes difficult, an intended reaction does not occur and selectivity of a targeted reaction product cannot be obtained. Also in the case of use as an acid-removing agent, a targeted acid cannot be trapped or 

separated and extracted. In the case of use for actuator application, intended moving performance cannot be obtained. 

[0048] Concretely the basic functional group Y 1 in Ry is preferably at least one selected from phosphoric acid amides, phosphoric acid imides, amines, imines, enamines, ketimines, hydroxylamines, amidines, azines, hydrazines, oximes and amine oxides, more preferably one selected from amines, imines, enamines, ketimines and azines, and par› ticularly preferably amines. 

[0049] When amine is bonded as a substituent to the carbon atom of aromatic ring as explained infra, any of primary amino group (-NH$_{2}$ ), secondary amino group (-NR $^{1 }$H) and tertiary amino group (-NR $^{2}$R3 ) can be used. Usually also in the case of secondary amino group and tertiary amino group, preferred is a lower amino group having a hydrocarbon group (R1, R 2 or R 3 ) having smaller number of carbon atoms from the viewpoint of oxidation resistance. For example, there are hydrocarbon groups hav› ing 1 to 10 carbon atoms, preferably hydrocarbon groups having 1 to 5 carbon atoms, more preferably methyl or ethyl. Particularly preferred from the viewpoint of oxidation resis› tance is a primary amino group (-NH$_{2}$ ). 

[0050] When a nitrogen atom of an amino group consti› tutes an aromatic ring at the same time, usually a form of secondary or tertiary amino group can be taken. Those cyclic amino groups themselves are more excellent in oxidation resistance, and when a monovalent hydrocarbon group is further bonded to the nitrogen atom of the cyclic amino group, hydrocarbon groups having smaller number of car› bon atoms are preferred in the same manner as mentioned above. For example, there are hydrocarbon groups having 1 to 10 carbon atoms, preferably hydrocarbon groups having 1 to 5 carbon atoms, more preferably methyl or ethyl. Preferred most from the viewpoint of oxidation resistance is a cyclic amino group in which a monovalent hydrocarbon group is not bonded to the nitrogen atom. 

[0051] In the ionic liquid type functional material of the present invention, it is preferable that the functional group contained in Ry is the salt Y 2 of the basic functional group or contains the salt Y 2 of the basic functional group. 

[0052] The salt Y 2 of the basic functional group is not limited particularly as far as it is a salt of the above› mentioned basic functional group Y 1 and an anionic ion (anion species), and is optionally selected depending on kind, function, purpose and application of the aromatic compound. 

[0053] Also the salt Y 2 of the basic functional group may $^{b}$1 a salt obtained by subjecting the basic functional group Y to cationic quatemization, for example, salts of quater› nary ammonium cation obtained by quatemizing amines. 

[0054] Examples of the anions in the salt Y 2 of the basic functional group are, for instance, anions derived from halogen atoms such as c1-, Br- and F-; anions derived from inorganic acids such as HSO$_{3}$ -, NO 3 -, ClO 4 -, PF 6 -, BF 4 - and SbF 6 -; and anions derived from organic acids such as CF$_{3}$SO$_{3 }$ -, -N(SO $_{2}$CF$_{3}$ ) 2 , -qso$_{2}$CF$_{3}$ ) 2 and -ocOCF$_{3}$ . 

[0055] Among them, anions preferred for an ionic liquid type functional material from the viewpoint of making liquefaction easy and making it possible to decrease a 

