SNAPSHOT: A New Method for Making Brilliant, Organic Dyes

(Credit: TU Wien) The intense, brilliant color of high-tech organic dyes comes at a price — the chemical processes used to make them are extremely harmful to the environment. And these dyes are vital for many modern electronics, like flat screens and debit card chips. But what if you could replace the typical toxic solvents with plain old water? Researchers at the Technische Universität Wien in Vienna, Austria, have done just that. And their find is made all the more impressive considering the hydrophobic — or water-repelling — nature of the dyes. You can see it in this image, where a drop of water slides right off some indigo dye powder. "If you were to listen to your initial gut feeling, you would actually suspect that water is the worst solvent imaginable for synthesising and crystallising these molecules," Miriam Unterlass from the Institute of Materials Chemistry at TU Wien said in a media release. But the group of scientists discovered a novel way of changing the usual properties of water by using special pressure vessels that heat the water to extremely high temperatures while still leaving it in liquid form. By ionizing the water, the dyes dissolve and crystallize without any additional chemicals. Their results were published in the journal Angewandte Chemie.