Novel fluorinated π-conjugated oligomers as electron transport materials in organic light emitting diodes

New partially fluorinated pi-conjugated oligomers have been synthesised by transition metal catalysed coupling reactions. These electron deficient arenes were applied as electron transport materials in organic light emitting devices using the blue luminescing p-hexaphenyl as active material. The threshold voltage is affected by lower or higher values compared to the single layer device, while quantum efficiency increases with all prepared charge transport materials reaching values up to 3.4%. A multilayer device using a partially fluorinated trimer with poly(azomthine) as hole transport material showed a turn-on voltage of approximately 3.4 V. (C) 1998 Published by Elsevier Science B.V.