NOVELTY - Benzimidazo(1,2-a)benzimidazole compounds, are new.    USE - As a hole transport layer, an electron/exciton blocking layer, or an emitting layer for an electronic device, particularly for electrophotographic photoreceptors, photoelectric converters, organic solar cells, switching elements, organic light emitting field effect transistors, image sensors, dye lasers and electroluminescent devices. The electronic device is used in an apparatus selected from stationary visual display units; mobile visual display units; illumination units; keyboards; items of clothing; furniture and wallpaper (claimed).    ADVANTAGE - The compounds provide improved efficiency, stability, manufacturability, or spectral characteristics of electroluminescent devices.    DETAILED DESCRIPTION - Benzimidazo(1,2-a)benzimidazole compounds of formula (I), are new.    R1 to R7=H, 1-25C alkyl (optionally substituted by E' and/or interupted by D'), 6-24C aryl (optionally substituted by G'), or 2-30C heteroaryl (optionally substituted by G');    X1=a group of formula -(A1)o-(A2)p-(A3)q-(A4)r-R'16;    o, p, q and r=0 or 1;    A1 to A4=6-24C arylene or 2-30C heteroarylene (both optionally substituted by G', and interrupted by at least one -(SiR17R18)-;    X2=a group of formula -(A5)v-(A6)s-(A7)t-(A8)u-R15, -NR10R11, or Si(R12)(R13)(R14);    v, s, t, u=0 or 1;    A5 to A8=6-24C arylene or 2-30C heteroarylene (both optionally substituted by G'; and interrupted by at least one -(SiR17R18)-);    R10 and R11=6-24C aryl or 2-30C heteroaryl (both optionally substituted by G');or    NR10R11=a heteroaromatic ring, or ring system;    R12 to R14=6-24C aryl or 2-30C heteroaryl (both optionally substituted by G') or 1-25C alkyl (optionally substituted by E' and or interupted by D');    R15 and R'16=6-24C aryl or 2-30C heteroaryl (both optionally substituted by G');    R17 and R18=1-25C alkyl or 6-24C aryl (both optionally substituted by at least one of 1-25C alkyl);    D'=-CO-, -COO-, -S-, -SO-, -SO2-, -O-, -NR65-, -SiR70R71-, -POR72-, -CR63=CR64-, or -C?=C-;    E'=-OR69, -SR69, -NR65R66, -COR68, -COOR67, -CONR65R66, -CN, or halo;    G'=E', 1-18C alkyl, or T1;    T1=6-24C aryl or 2-30C heteroaryl (both optionally substituted by F or 1-18C alkyl (which is interrupted by O));    R63 and R64=H, 6-18C aryl (optionally substituted by 1-18C alkyl, or 1-18C alkoxy), or 1-18C alkyl (which is interrupted by -O-);    R65 and R66=6-18C aryl (optionally substituted by 1-18C alkyl or 1-18C alkoxy) or 1-18C alkyl (which is interrupted by -O-);or    R65+R66=5- or 6-membered ring;    R67=6-18C aryl (optionally substituted by 1-18C alkyl or 1-18C alkoxy) or 1-18C alkyl (which is interrupted by -O-);    R68=H, 1-18C aryl (optionally substituted by 1-18C alkyl or 1-18C alkoxy) or 1-18C alkyl (which is interrupted by -O-);    R69=1-18C aryl (optionally substituted by 1-18C alkyl or 1-18C alkoxy) or 1-18C alkyl (which is interrupted by -O-);    R70 and R71=1-18C alkyl or 1-18C aryl (optionally substituted by 1-18C alkyl);    R72=1-18C alkyl or 1-18C aryl (optionally substituted by 1-18C alkyl).    INDEPENDENT CLAIMS are included for the following:    (1) an electronic device comprising the compound (I);    (2) a hole transport layer, an electron/exciton blocking layer, or an emitting layer comprising the compound;    (3) an apparatus selected from stationary visual display units; mobile visual display units; illumination units; keyboards; items of clothing; furniture; wallpaper, comprising the organic electronic device, or the hole transport layer, the electron/exciton blocking layer, or the emitting layer;    (4) new intermediate compound of formula (II); and    (5) preparation of the compound (II) (where X4 is -(A1)o-(A2)p-(A3)q-(A4)r-R'16 and X3 is Cl, Br, or I) involving halogenation of benzimidazo(1,2-a)benzimidazole compound of formula (III).    X4=a group of formula -(A1)o-(A2)p-(A3)q-(A4)r-R'16 or A1-(A2)p-(A3)q-(A4)r-R16a;    X3=a group of formula -(A5)v-(A6)s-(A7)t-(A8)u-R15a;    R15a and R16a=Cl, Br, I, ZnX12, -Sn207R208R209, -B(OH)2, -B(OY1)2, BF4Na, -BF4K or a group of formula (iia) or (iib);    X12=halo;    R207 to R209=H or 1-8C alkyl, where two radicals optionally form a common ring and these radicals are optionally branched or unbranched;    Y1=1-18C alkyl;    Y2=2-10C alkylene;    Y13 and Y14=H or 1-18C alkyl.