MIT engineers are redefining the 3D printing process with a new method that not only enables the creation of complex designs but also significantly reduces waste. Traditionally used in the production of customized items such as dental implants and hearing aids, vat photopolymerization—the technique at the heart of this innovation—often results in excess material being discarded after the removal of support structures. However, according to a report by MIT News, this new method promises to change that.
With a novel resin that reacts differently under ultraviolet light and visible light, structures can now be printed without the subsequent waste typically associated with support materials—support structures that were necessary to prop up the product during the printing process can now be dissolved in a variety of solutions, including something as safe as baby oil, enabling a significant step toward sustainability. "You can now print — in a single print — multipart, functional assemblies with moving or interlocking parts, and you can basically wash away the supports," graduate student Nicholas Diaco said in a statement obtained by MIT News.
Previous methods of vat photopolymerization involved manually removing these supports, but MIT’s new light-sensitive resin can distinguish between a sturdy final product and a soluble support system allowing for a quick dip in a solution to reveal the finished piece. This not only quickens the production process but it also presents an opportunity for the resin to be recycled and reused—once the support dissolves, it can be reintegrated into the resin bath, used for printing new parts.
The research conducted by Diaco and colleagues demonstrated the successful use of their method in printing detailed, functional gear trains, lattices, and even a whimsical example—a small dinosaur encased in an egg, revealed through the dissolution of the support material. According to their findings, detailed in a paper published today in Advanced Materials Technologies, this innovation has the potential to streamline and sustain the manufacturing of intricate 3D-printed items. MIT Professor of Mechanical Engineering John Hart told MIT News, “Along with automated part handling and closed-loop reuse of the dissolved resin, this is an exciting path to resource-efficient and cost-effective polymer 3D printing at scale.”
Support for this project came from sources including the Center for Perceptual and Interactive Intelligence (InnoHK), the U.S. National Science Foundation, the U.S. Office of Naval Research, and the U.S. Army Research Office, promising broad institutional backing for future development and refinement of this environmentally conscious, waste-reducing technology.
