NOVELTY - A 2H-benzotriazole compound for used electroluminescent devices, electrophotographic photoreceptors, photoelectric converters, solar cells, image sensors, and dye lasers, is new    USE - The invention is for used electroluminescent (EL) devices, electrophotographic photoreceptors, photoelectric converters, solar cells, image sensors, and dye lasers (claimed). The compounds (A-1)-(A-12) are used as host compounds, compounds (B-1) to (B-10) and compounds (D-1) to (D-9) are used as guest compounds in the light-emitting layer of EL devices. The inventive compounds can function as blue-emitting organic compound, hole-injecting, hole-transporting, and electron-injecting or an electron-transporting material. The organic EL device is used for a flat panel display of an on-wall television set, flat light-emitting device, light source for a copying machine or printer, light source for a liquid crystal display or counter, display signboard, and signal light.    ADVANTAGE - The invention provides an organic EL device having improved EL device characteristics, such as light emission efficiency and maximum light emission brightness. The organic EL device is remarkably stable against heat and electric current, and gives usable light emission brightness at a low actuation voltage. It remarkably decreases the problematic deterioration of conventional devices.    DETAILED DESCRIPTION - 2H-Benzotriazole compound of formulae (I) or (II) is new.    Y1 = divalent linking group;    Y3 = 1-25C alkyl, especially 1-4C alkyl, aryl, or heteroaryl that can optionally be substituted, 6-30C aryl, or 2-26C heteroaryl that can be optionally substituted;    Ar1, Ar2 groups = formulae A - D;    A11-A18, A21-A24 = H, halogen, especially F, OH, 1-24C alkyl substituted with E and/or interrupted with D, 1-24C perfluoroalkyl, 6-14C perfluoroaryl, especially pentafluorophenyl, 5-12C cycloalkyl (that is substituted with G and/or interrupted with S-, -O-, or NR25-, -NR25R26, 1-24C alkylthio, -PR32R32), 5-12C cycloalkoxy (that is substituted with G, 1-24C alkyl, 5-12C cycloalkyl,, 7-25C aralkyl, 1-24C perfluoroalkyl), 6-14C perfluoroaryl, especially pentafluorophenyl, 1-24C haloalkyl, 2-20C heteroaryl (that is substituted by G, fluorine, 1-24C alkyl, 5-12C cycloalkyl, 7-25C aralkyl, 1-24c perfluoroalkyl, 6-14C perfluoroaryl, especially pentafluorophenyl or 1-24C haloalkyl), 2-24C alkenyl, 2-24C alkynyl, 1-24C alkoxy, 1-24C alkoxy that is substituted by E and/or interrupted by D, 7-25C aralkyl, 7-25C aralkyl that is substituted by G, 7-25C aralkoxy, 7-25C aralkoxy that is substituted by G, -CO-R28, formulae E, F, or two groups of A11-A18 that are neighboring to each other from formulae G or H;    A31-A36 = H, halogen, hydroxy, 1-24C alkyl, 1-24C alkyl that is substituted by E and/or interrupted by D, 1-24C perfluoroalkyl, 6-14C perfluoroaryl, especially pentafluorophenyl, 5-12C cycloalkyl, 5-12C that is substituted by G and/or interrupted by S-, -O-, or -NR25-, 5-12C cycloalkoxy, 5-12C cycloalkoxy that is substituted by G, 6-24C aryl, 6-24C aryl that is substituted by G, 2-20C heteroaryl, 2-20C heteroaryl that is substituted by G, 2-24C alkenyl, 2-24C alkynyl, 1-24C alkoxy, 1-24C alkoxy that is substituted by E and/or interrupted by D, 7-25C aralkyl, 7-25C aralkyl that is substituted by G, 7-25C aralkoxy, 7-25C aralkoxy that is substituted by G, or -CO-R28 where the substituent(s) from A11-A18 and A21-A24 is 6-24C aryl that is substituted with fluorine, 1-24C alkyl, 5-12C cycloalkyl, 7-25C aralkyl, 1-24C perfluoroalkyl, 6-24C perfluoroaryl, especially pentafluorophenyl or 1-24C haloalkyl, 2-26C heteroaryl, especially thiophenyl, pyrrolyl, furanyl, benzoxazolyl, or benzothiazolyl that is substituted by fluorine, 1-24C alkyl, 5-12C cycloalkyl, 7-25C aralkyl, 1-24C perfluoroalkyl, 6-14C perfluoroaryl, especially pentafluorophenyl or 1-24C haloalkyl, or a group of formulae I - N;    X70-X77, X80-X87 = E and/or interrupted by D, 1-24C perfluoroalkyl, 6-14C perfluoroaryl, especially pentafluorophenyl, 5-12C cycloalkyl (that is substituted by G and/or interrupted by S-, -O-, or -NR25-, -NR25R26, 1-24C alkylthio, -PR32R32), 5-12C cycloalkoxy, 5-12C cycloalkoxy that is substituted by G, 6-24C aryl, 6-24C aryl that is substituted by G, 1-24C alkyl, 5-12C cycloalkyl, 7-25C aralkyl, 1-24C perfluoroalkyl, 6-14C perfluoroaryl, especially pentafluorophenyl or 1-24C haloalkyl, 2-20C heteroaryl, 2-20C heteroaryl that is substituted by G, fluorine, 1-24C alkyl, 5-12C cycloalkyl, 7-25C aralkyl, 1-24C perfluoroalkyl, 6-14C perfluoroaryl, especially pentafluorophenyl or 1-14C haloalkyl, 2-24C alkenyl, 2-24C alkynyl, 1-24C alkoxy, 1-24C alkoxy that is substituted by E and/or interrupted by D, 7-25C aralkyl, 7-25C aralkyl that is substituted by G, 7-25C aralkoxy, 7-25C aralkoxy that is substituted by G, -CO-R28, or two groups of X70-X77 and X80-X87 that are neighboring to each other from formulae O or P;    See Definition Field for remaining Markush definitions.