Organic pigment nanoparticle thin film devices via Lewis acid pigment solubilization and in situ pigment dispersions

We introduce a new pigment processing approach, namely Lewis acid pigment s olubilization (LAPS), for the fabrication of organic pigment thin film devi ces. The process involves the solubilization of an organic pigment in a Lew is acid/nitromethane solution. The resulting solution can be used to solven t cast pigment/Lewis acid thin films, which are then washed with an aqueous solution to remove the Lewis acid and give the final pigmented layers. Alt ernately, the pigment/Lewis acid solution can be used for acid pasting to g ive pigment wet cakes, which can then be used for preparing in situ pigment dispersions suitable for solvent coating. A wide range of organic pigment thin dim devices can be fabricated using these processes, as we demonstrate in this article for the fabrication of organic photoreceptors.