A novel range of potentially electroluminescent materials for Langmuir-Blodgett deposition

Abstract A range of amphiphiles based around 5-aminophthalimide has been synthesised with fluorescent polycyclic aromatic headgroups and long chain hydrocarbon tails. The molecules all fluoresce strongly in solution with emission bands between 425 nm and 480 nm. It is hoped that these materials, deposited as Langmuir-Blodgett (LB) films, can be used as emitter layers in blue electroluminescent (EL) devices. Preliminary characterisation work with long chain N -n-alkyl-5-aminophthalimides and 5-( N -n-alkylamido) phthalimides has led to reproducible Langmuir films on the water surface. Molecular areas, which are largely independent of subphase pH, indicate molecular areas of 0.324 nm 2 and 0.341 nm 2 , respectively. This suggests that the molecules are titled at a slight angle from the normal. LB films have been successfully deposited onto a range of possible substrates. Several characterisation techniques have been used to confirm reproducible deposition in alternate layer structures.