NOVELTY - A 4-naphthalen-1-yl-7H-benzo(c)fluorine derivative (I) is new.    USE - New naphthalenyl-benzofluorine derivative is used for organic electric device e.g. organic electroluminescent device, organic solar cell, organophotoreceptor, organic thin film transistor, and monochrome or white illumination device for electronic display device (all claimed).    ADVANTAGE - The electronic display device containing the naphthalenyl-benzofluorine derivative has improved luminous efficiency and durability.    DETAILED DESCRIPTION - A 4-naphthalen-1-yl-7H-benzo(c)fluorine derivative of formula (I) is new.    Ar1=6-60C aryl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 1-20C alkoxy, 1-20C alkylamine, 1-20C alkylthiophene, 6-20C arylthiophene, 2-20C alkenyl, 2-20C alkynyl, 3-20C cycloalkyl, 6-20C aryl (optionally substituted by D), 8-20C arylalkenyl, silane, boron, germanium or 2-20C heterocyclyl), 2-60C heterocyclyl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C arylamine, 6-60C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene) containing heteroatom chosen from O, N, S, Si and P, 6-60C arylamine (optionally substituted by H, D, tritium, halo, amino, nitrile, nitro, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 2-30C heterocycloalkyl, 6-60C aryl or 2-60C heterocyclyl) or fluorine (optionally substituted by H, D, tritium, halo, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 1-50C alkyl, 2-20C heterocyclyl, nitrile or acetylene);    Ar2=6-60C aryl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 1-20C alkoxy, 1-20C alkylamine, 1-20C alkylthiophene, 6-20C arylthiophene, 2-20C alkenyl, 2-20C alkynyl, 3-20C cycloalkyl, 6-20C aryl (optionally substituted by D), 8-20C arylalkenyl, silane, boron, germanium or 2-20C heterocyclyl), or 2-60C heterocyclyl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C arylamine, 6-60C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene) containing heteroatom chosen from O, N, S, Si and P;    R1,R2=1-50C alkyl (optionally substituted by H, D, tritium, halo, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene), or 6-60C aryl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 1-20C alkoxy, 1-20C alkylamine, 1-20C alkylthiophene, 6-20C arylthiophene, 2-20C alkenyl, 2-20C alkynyl, 3-20C cycloalkyl, 6-20C aryl (optionally substituted by D), 8-20C arylalkenyl, silane, boron, germanium or 2-20C heterocyclyl);    or R1+R2=spiro compound;and    R3,R4=1-50C alkyl (optionally substituted by H, D, tritium, halo, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene), 2-60C heterocyclyl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C arylamine, 6-60C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene) containing heteroatom chosen from O, N, S, Si and P, 2-20C alkenyl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 6-20C arylamine, 6-60C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene), 6-60C arylamine (optionally substituted by H, D, tritium, halo, 2-20C alkenyl, 1-20C alkoxy, 1-30C alkoxy (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene), 6-60C arylamine (optionally substituted by H, D, tritium, halo, amino, nitrile, nitro, 1-20C alkyl, 2-20C alkenyl, 1-20C alkoxy, 3-30C cycloalkyl, 2-30C heterocycloalkyl, 6-60C aryl or 2-60C heterocyclyl), 6-30C aryloxy (optionally substituted by H, D, tritium, halo, 2-20C alkenyl, 1-20C alkoxy, 6-20C aryl (optionally substituted by D), 7-20C arylalkyl, 8-20C arylalkenyl, 2-20C heterocyclyl, nitrile or acetylene), or 6-60C aryl (optionally substituted by H, D, tritium, halo, 1-20C alkyl, 1-20C alkoxy, 1-20C alkylamine, 1-20C alkylthiophene, 6-20C arylthiophene, 2-20C alkenyl, 2-20C alkynyl, 3-20C heterocycloalkyl, 6-20C aryl (optionally substituted by D), 8-20C arylalkenyl, silane, boron, germanium or 2-20C heterocycloalkyl).    Adjacent of R1-R4, Ar1 and Ar2 combine to form optionally substituted saturated or unsaturated ring. INDEPENDENT CLAIMS are included for the following:    (1) organic electric device, which has organic layer including 4-naphthalen-1-yl-7H-benzo(c)fluorine derivative; and    (2) electronic display device, which has organic electric device and control unit.