Ink with defined breaking points allows 3-dimensional laser-written microstructures to be written, erased and rewritten.
KIT
With direct laser writing, a computer-controlled, focused laser beam generates the structure in a photoresist, similar to a pen. Researchers at Karlsruhe Institute of Technology (KIT) have now developed an erasable ink with reversible bonding that has building blocks that can be cleaved from each other. The printed structure can simply be erased by immersing it in a chemical solvent. At the deleted point, a new structure can then be rewritten. In this way, the structure can be modified repeatedly. The process has been developed in close co-operation with Professor Martin Wegener’s group at the Institute of Applied Physics and at the Institute of Nanotechnology at KIT. The physicists have developed highly specialised 3D printers that produce scaffolds of up to 100 nanometres in size by direct laser writing.
Structures written with erasable ink should be able to be integrated into structures made of non-erasable ink. This would open up a wide range of new application possibilities in biology or material development, for example. According to Wegener, support constructions, similar to those used in bridge building, can be 3D printed, and removed again in the further production process. Using erasable conducting structures, it would also be possible to produce reversible wire bonds as electronic components in the future. By mixing a permanent ink with an erasable ink, the properties of the printed material can be influenced to make it more or less porous, for example.
The participating scientists are presenting their new process in the prestigious journal Angewandte Chemie under the title “Cleaving Direct Laser Written Microstructures on Demand” for the first time. The reviewers have rated this publication a “very important paper” and have highlighted it.