Angewandte Chemie International Edition
Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Inside Cover: Writing Self-Erasing Images using Metastable Nanoparticle “Inks” (Angew. Chem. Int. Ed. 38/2009)
Light-sensitive inks for self-erasing images are formed from metal nanoparticles (NPs) covered with photoswitchable ligands dispersed in a polymer film, as described by B. A. Grzybowski and co-workers on page 7035 ff. Upon exposure to UV light, the NPs form metastable aggregates; the apparent color corresponds to the degree of aggregation. In the absence of light, the aggregates fall apart and the images gradually self-erase. Multicolor images can be also be created with a single NP ink.