At the Demo conference today, a company called Zink showed off a thermal printer that uses no ink, and is small enough to fit in your pocket or be built into a compact point and shoot camera. It turns out that to do this, the company had to invent a whole new class of chemicals, which they've (oh so creatively) dubbed Thermoamorphochromic Crystals.
The key to the printer is the paper. Each sheet has three color layers--cyan, magenta, and yellow--on top of a plastic base layer. These color layers are made from the new chemicals, which have an interesting trait: in their natural crystalline state they are colorless, but if you break up this crystal structure they become vibrantly hued. In other words, the chemicals don't change, just the arrangement of the molecules.
In traditional thermal printers, small heating elements pass over an ink ribbon, transferring color to paper. In Zink's process, the heated print head simply alters the molecular structure of the chemical layers, producing the same result in a few seconds, with no ink to smudge or dry. Wicked.
