Erasable 3D Printing

Those of you old enough to have used a typewriter probably remember what a miracle the automatic erasing function on an electric model was—if you made a mistake, you didn’t have to blot it with messy liquid paper anymore; the typewriter could do it for you while you were still writing.

Computers have made that whole process unnecessary for regular printing, but what about for 3D printing? If there’s an error in a structure, you pretty much have to start the build over again. That’s the problem that researchers at the Karlsruhe Institute of Technology (KIT) appear to have solved by creating a method to “erase” a direct laser written structure up to 100 nm in size and then rewrite it repeatedly.

The ink the researchers developed has reversible bonding, so the printed structure can be erased by immersing it in a chemical solvent. A new structure can then be rewritten at the same point.

The structures are formed via direct laser writing irradiation of a phenacyl sulfide linker. Exposing the material to dithiothreitol cleaves the bonds and erases the structure.

"The ink with defined breaking points can be used for a variety of applications," doctoral student and first author Markus Zieger said.

Structures written with this erasable ink can be integrated into other structures made of non-erasable ink. For example, support constructions can be produced by 3D printing and then later removed via erasing. According to the researchers, it is also possible to further develop 3D designer petri dishes for use in biology applications.

It would also be feasible to create reversible wire bonds from erasable conducting structures in the future.

The research appeared in the journal Angewandte Chemie in a paper titled “Cleaving Direct Laser Written Microstructures on Demand.”

Source: Science Daily