NOVELTY - A fluorene-type compound (I) is new.    USE - New fluorene-type compound is used for oligomer, polymer or dendrimer for formulation used as hole-transport material for forming hole-transport layer or hole-injection layer, and matrix material for forming emitting layer used in electronic device e.g. organic integrated circuit, organic field-effect transistor, organic thin-film transistor, organic light-emitting transistor, organic solar cell, organic optical detector, organic photoreceptor, organic field-quench device, light-emitting electrochemical cell, organic laser diode and organic electroluminescent device (all claimed).    ADVANTAGE - The electronic device obtained by the formulation containing the oligomer, polymer or dendrimer formed by the fluorene-type compound has excellent durability, power efficiency and low operating voltage.    DETAILED DESCRIPTION - A fluorene-type compound (I) is new.    Ar1=6-30C aromatic ring or 5-30C heteroaryl substituted by RA and R1;    Ar2=6-30C aromatic ring or 5-30C heteroaryl substituted by R1;    RA=F, Cl, CN, Si(R3)3, linear alkyl, alkoxy or 1-40C thioalkyl, branched or cyclic alkyl, alkoxy, 3-40C thioalkyl, alkenyl, 2-40C alkynyl (all substituted by R3), in which one or more adjacent or non-adjacent CH2 in RA is optionally replaced by -R3C=CR3-, -C?C-, -Si(R3)2-, C=O, C=NR3, -COO-, -CONR3-, -NR3-, P(=O)(R3), -O-, -S-, SO or S02, and one or more H atoms in RA is optionally replaced by D, F, CI, Br, I, CN or NO2;    R1=H, D, F, CI, Br, I, B(OR3)2, CHO, C(O)R3, CR3=C(R3)2, CN, COOR3, CON(R3)2, Si(R3)3, N(R3)2, NO2, P(=O)(R3)2, OSO2R3, OH, S(=O)R3, S(=O)2R3, linear alkyl, alkoxy, 1-40C thioalkyl, branched or cyclic alkyl, alkoxy, 3-40C thioalkyl, alkenyl, 2-40C alkynyl (all substituted by R3, aryloxy or 5-60C heteroaryloxy), in which adjacent or non-adjacent CH2 in R1 is optionally replaced by -R3C=CR3-, -C=C-, Si(R3)2, Ge(R3)2, Sn(R3)2, C=O, C=S, C=Se, C=NR3, -COO-, -CONR3-, NR3, P(=O)(R3), -O-, -S-, SO or SO2 and H atoms in R1 is optionally replaced by D, F, CI, Br, I, CN or NO2, aromatic or 5-60C heteroaryl;    two or more R1=aliphatic or aromatic ring;    R3=H, D, F, aliphatic group, aromatic group or 1-20C heteroaryl, in which one or more H atoms is optionally replaced by D or F;and    two or more R3=aliphatic or aromatic ring.    INDEPENDENT CLAIMS are included for the following:    (1) formulation, which comprises compound (I), solvent and polymer, oligomer or dendrimer; and    (2) electronic device, which contains formulation.