NOVELTY - Silyl substituted aromatic compounds (Q) are new.    USE - (Q) are useful as building block in polymerization and/or crosslinking reactions; in formulations for liquid processed applications in organo electronic applications, preferably organic light diodes; as matrix material, hole/exciton block material (both preferred), electron/exciton block material, hole-injection material, electron-injection material, hole conductor material, electron conductor material, hole conductor and/or electron conductor. The organic light diode is useful in stationary screens, screens of computers, TV, printers, mobile phone, laptop, digital cameras and MP3 (MPEG-1 Audio Layer 3)-players, vehicles, target notice at buses and pathways, kitchens devices, billboards, lights, sign-board, illumination units, keyboards, garment, furniture, and wallpaper (all claimed). (Q) are useful in organic solar cells, organic transistors, sensors, transistors and data storage.    ADVANTAGE - (Q) provide organic light-emitting diodes with long operational life, good efficiency, and high stability against thermal stress.    DETAILED DESCRIPTION - Silyl substituted aromatic compounds (Q) of formula (I) or (Ib) are new.    X = NR, S, O or PR;    R = (hetero)aryl, alkyl, cycloalkyl or heterocycloalkyl;    A = -NR6R7, -P(O)R8R9, -PR10R11, -S(O)2R12, -S(O)R13, -SR14 or -OR15;    R1-R3 = (hetero)aryl, alkyl, cycloalkyl, heterocycloalkyl, crosslinkable or polymerizable group bonded over a spacer group, where at least one of R1-R3 contains at least 2C, or OR22;    R4, R5 = alkyl, cycloalkyl, heterocycloalkyl, (hetero)aryl, crosslinkable or polymerizable group bonded over a spacer group, a group A or a group with donor- or acceptor effect;    n, m = 0-3;    R6R7N = a cyclic residue with 3-10 ring atoms (optionally substituted by one or more alkyl, cycloalkyl, heterocycloalkyl, (hetero)aryl and a group with donor or acceptor effect and optionally annelated with one or more further cyclic residue having 3-10 ring atoms, where the annelated residue is optionally substituted by alkyl, cycloalkyl, heterocycloalkyl, (hetero)aryl, a crosslinkable or polymerizable group bonded over a spacer group, or a group with donor- or acceptor effect);    R22 = SiR23R24R25, (hetero)aryl, alkyl, cycloalkyl, heterocycloalkyl, a crosslinkable or polymerizable group bonded over a spacer group optionally substituted by OR28;    R28 = SiR23R24R25 = SiR23R24R25, (hetero)aryl, alkyl, cycloalkyl, heterocycloalkyl, or a crosslinkable or polymerizable group bonded over a spacer group; and    R8-R15, R23-R25 = (hetero)aryl, alkyl, cycloalkyl, heterocycloalkyl, or a crosslinkable or polymerizable group bonded over a spacer group.    Where: two units of (Q) are bridged together over an optionally saturated, optionally at least a heteroatom interrupted bridge or over O, the bridging in (Q) respectively takes place at R2, in which Si atoms are bonded. INDEPENDENT CLAIMS are included for:    (1) the preparation of (Q);    (2) the preparation of crosslinkable and polymerizable material containing (Q) in crosslinkable or polymerizable form, comprising preparing (Q), in which at least one of R1-R25 or R28 contains a crosslinkable or polymerizable group bonded over a spacer, and crosslinking or polymerizing (Q);    (3) the crosslinked or polymerized material obtained by the above process;    (4) an organic light diode comprising (Q); and    (5) a light-emitting layer, block layer for hole/exciton comprising (Q).