1. Electroluminescent materials

Generally speaking, EL electroluminescent materials in the art (low-molecular-weight molecules or polymers) attempt to combine :

• good solid-state photoluminescence performance;

• good charge transport properties (high carrier mobility).

In the case of low-mass molecules, high photoluminescence efficiencies can be achieved in the solid state by doping the emitting layers (see [ ]). Polymers, on the other hand, are generally not doped, although some can achieve high fluorescence efficiencies. For example, poly[2-(dimethyloctylsilyl)-1,4-phenylenevinylene] (DMOS-PPV) and poly[9,9-bis(methoxyethoxyethyl)fluorene] (BDOH-PF) (figure 1 ) have η _...