Emission Patterning Using a Novel Amorphous Molecular Fluorophore with Three Cyanostilbene Moieties

A novel amorphous molecular fluorophore with three cyanostilbene moieties (TCSA) has been designed and synthesized. It was found that TCSA readily form amorphous glass with a glass transition temperature of 97 °C. Both crystalline sample and spin-coated amorphous film of TCSA exhibited fluorescence as well as in solution. In addition, TCSA exhibited mechanochromic emission. Although the emission color change is not so much clear for naked eye, the emission spectra of the crystal was changed by grinding due to amorphization. It was also found that photochemical [2+2] cycloaddition through cyanostilbene moieties took place in the amorphous film upon irradiation with intense UV light. The reaction resulted in quenching the fluorescence emission and therefore emission pattern could be fabricated on the amorphous film by UV irradiation through an appropriate mask.