A team of Autodesk researchers and dedicated UC Berkeley students has released a report outlining three key approaches to improving the safety and sustainability of SLA 3D printing materials by asking “what would nature do?" The findings point to several naturally-derived materials that can replace toxic elements found in today's commercial resins.

                  Image of electrospun chitosan fiber strand via msaustero & Autodesk

While 3D printing is opening many doors for modern manufacturing—producing previously unimaginable geometries in record time and with little material waste—the undeniable drawback is that many 3D printing materials, and SLA resins in particular, are toxic to both humans and the environment.

“Products manufactured using 3D printing should be safe for humans and the environment throughout their lifespan: during their production, use, and disposal. Unfortunately, the chemical hazards associated with many of today’s SLA 3D printing materials present considerable drawbacks in all these areas,” explain Michael Floyd and Susan Gladwin of Autodesk, which sponsored the research.

“The development of ‘biofriendly’ materials—that are safe and sustainable—for 3D printing will allow for new use cases and open up whole new markets. Solving this piece of the puzzle is therefore critical to unlocking AM’s larger potential.”

The report begins with a health and hazard assessment of the 3D printing resins used in Autodesk’s Ember SLA 3D printer, as well as other commercially-available SLA resins. This assessment found that even after the polymerization process (where the resin is hardened via a UV light source), residual resin remains. This resin is considered a toxic, hazardous waste, and can cause sensitization over time, leading to increasingly harmful reactions in humans, including asthma and skin rashes.

                                              Autodesk Ember SLA 3D Printer

In order to find an alternative, non-toxic formula (or formulas), the researchers focused on the concept of biomimicry that is, borrowing ideas from the natural world and applying them to technological development. The theory is that nature itself already provides the most efficient, sustainable and beneficial materials and processes, so why try to replace them with toxic and limited man-made 'solutions'? 

Specifically, the team began with PR48, also known as Autodesk’s Standard Clear Prototype Resin. Using PR48 as a starting point allowed the researchers to isolate exactly which elements within the resin were hazardous, and devise a way to replace or eliminate them.

Story Source: