Ayyappanpillai Ajayaghosh, Samrat Ghosh
The present invention describes the development of a novel supramolecular black dye from a DPP based low molecular weight organogelator. DPP-Black can form a black organogel in toluene (critical gelation concentration of 4mg/ml) with a full spectral coverage from 300 nm to 800 nm and transmits beyond 850 nm. In the gel state, complete visible spectral coverage was achieved because of the presence of both H- and J- type aggregates, which was confirmed via absorption studies. To create an NIR transmitting elastomeric black filter nanoscopic molecular aggregates of DPP-Black into a polydimethylsiloxane (PDMS) (0.15 wt %) matrix have been embedded. This filter can be used for 850 nm bandpass as well as for NIR photography, security and forensic related applications.