NOVELTY - Electroluminescent device comprises at least one 2-diarylaminofluorene compound (I).    USE - Electroluminescent device such as an organic light-emitting transistor, an organic field-quench device, an organic light-emitting electrochemical cells, an organic laser diode and organic light emitting diode. (II) is useful: in an electronic device including organic integrated circuits, organic FETs, organic thin-film transistors, organic light-emitting transistors, organic solar cells, organic optical detectors, organic photoreceptors, organic field-quench devices, light emitting electrochemical cells, organic laser diodes and organic electroluminescent devices such as organic light emitting diode; and as a hole transport material in a hole transport or hole injection layer, matrix material in an emitting layer, an electron blocking material, and an exciton-blocking material (all claimed).    ADVANTAGE - (I) provides improved performance, thermal stability, efficiency and service life to the electronic device.    DETAILED DESCRIPTION - Electroluminescent device comprises at least one 2-diarylaminofluorene compound of formula (I).    Ar1, Ar2 = aryl or heteroaryl having 10-60 aromatic ring atoms, which are substituted with one or more radicals R4 that are same or different from each other, where both groups Ar1 or Ar2 contain at least two or more aryl or heteroaryl rings;    R1 = H, D, F, Cl, Br, I, C(=O)R5, CN, Si(R5)3, NO2, P(=O)(R5)2, S(=O)R5, S(=O)2R5, linear 1-20C-alkyl, -alkoxy, -thioalkyl, branched or cyclic 3-20C-alkyl, -alkoxy, -thioalkyl, 2-20C-alkenyl, -alkynyl, aryl or heteroaryl ring system having 6-30 aryl ring atoms, which are optionally substituted by one or more radicals R5, or condensed ring system having 9-30 ring atoms, which are substituted by one or more radicals R5, where the abovementioned groups are optionally substituted with one or more radicals R5, one or more CH2-groups in the abovementioned groups are replaced by -R5C=CR5, -CC-, Si(R5)2, C=O, C=S, C=NR5, -C(=O)O-, -C(=O)NR5, P(=O)(R5), -O-, -S-, SO or SO2, one or more H-atoms in the abovementioned groups are replaced by D, F, Cl, Br, I, CN or NO2, aryl or heteroaryl fused rings do not include more than 10 ring atoms, both radicals of R1 form a ring circuit so that a spiro compound is formed, and the ring formed by the two radicals of R1 is not condensed with aryl or heteroaryl rings;    R2-R4 = H, D, F, Cl, Br, I, C(=O)R5, CN, Si(R5)3, NO2, P(=O)(R5)2, S(=O)R5, S(=O)2R5, linear 1-20C-alkyl, -alkoxy, -thioalkyl, branched or cyclic 3-20C-alkyl, -alkoxy, -thioalkyl, 2-20C-alkenyl, -alkynyl, or aryl or heteroaryl ring system having 6-30 aryl ring atoms, which are optionally substituted by one or more radicals R5, where the abovementioned groups are optionally substituted with one or more radicals R5, one or more CH2-groups in the abovementioned groups are replaced by -R5C=CR5, -CC-, Si(R5)2, C=O, C=S, C=NR5, -C(=O)O-, -C(=O)NR5, P(=O)(R5), -O-, -S-, SO or SO2, and one or more H-atoms in the abovementioned groups are replaced by D, F, Cl, Br, I, CN or NO2;    R5 = H, D, F, Cl, Br, I, C(=O)R6, CN, Si(R6)3, NO2, P(=O)(R6)2, S(=O)R6, S(=O)2R6, linear 1-20C-alkyl, -alkoxy, -thioalkyl, branched or cyclic 3-20C-alkyl, -alkoxy, -thioalkyl, 2-20C-alkenyl, -alkynyl, aryl or heteroaryl ring system having 6-30 aryl ring atoms, which are optionally substituted by one or more radicals R6, or aryloxy or aralkyl having 5-30 aryl ring atoms, which are substituted with one or more radicals R6, where the abovementioned groups are substituted with one or more radicals R6, one or more CH2-groups in the abovementioned groups are replaced by -R6C=CR6, -CC-, Si(R6)2, C=O, C=S, C=NR6, -C(=O)O-, -C(=O)NR6, P(=O)(R6), -O-, -S-, SO or SO2, and one or more H-atoms in the abovementioned groups are replaced by D, F, Cl, Br, I, CN or NO2;    R6 = H, D, F, aliphatic, aryl or heteroaryl organic radical having 1-20C, in which one or more H atoms are replaced by D or F, provided that (I) does not contain other polycyclic or condensed groups in addition to fluorene condensed or polycyclic groups in position 9 of the fluorene;    n = 0-4, preferably 0-2; and    m = 0-3, preferably 1.    INDEPENDENT CLAIMS are included for:    (1) a fluorene compound of formula (II);    (2) the preparation of (I);    (3) a composition comprising (I), polymers, oligomers or dendrimers, and at least another organic functional material consisting of fluorescent emitter, phosphorescent emitter, host materials, matrix materials, electron-transporting materials, electron injection materials, hole conductor materials, hole injection materials, electron-blocking materials and hole-blocking materials; and    (4) a formulation comprising (I) or polymer, oligomer or dendrimer, and at least one solvent.    Ar3, Ar4 = aryl or heteroaryl having 10-60 aromatic ring atoms, which are substituted with one or more radicals R5 that are same or different from each other, where both groups Ar3 and Ar4 optionally contain at least two or more aryl or heteroaryl rings;    R7 = linear 1-20C-alkyl, -alkoxy, -thioalkyl, branched or cyclic 3-20C-alkyl, -alkoxy, -thioalkyl, 2-20C-alkenyl, -alkynyl, aryl or heteroaryl ring system having 6-30 aryl ring atoms, which are optionally substituted by one or more radicals R5, or condensed ring system having 9-30 ring atoms, which are substituted by one or more radicals R5, where aryl or heteroaryl condensed rings do not contain more than 10 ring atoms, two radicals of R7 together form a ring closure so that a spiro compound is formed, the ring formed by the two radicals of R7 is not condensed with aryl or heteroaryl rings, and R8 is an aryl or heteroaryl ring system having 6-30 ring atoms, which are optionally substituted by one or more radicals R5 when R7 is a linear or branched alkyl group;    R8 = H, D, or aryl or heteroaryl ring system having 6-30 ring atoms, which are optionally substituted by one or more radicals R5, where, when R8 is H, R7 is aryl or heteroaryl ring system having 6-30 aromatic ring atoms; and    a = 1-4, preferably 1, provided that (II) does not comprise further polycyclic or condensed groups in addition to the fluorene and condensed or polycyclic groups in position 9 of the fluorene and does not contain halogens.