Additive manufacturing, also known as 3D printing, has so far been used for simple construction. In this process, a computer creates three-dimensional objects by depositing materials, usually in layers. But now, the National Institute for Standards in Technology (NIST) is working to unlock additive manufacturing’s potential. For example, earlier this year, NIST researchers worked with polyelectrolyte complexes (PECs), resins with properties useful in fire protection, food packaging, drug delivery, insulation, and more. The scientists incorporated a technique that uses light to solidify a liquid resin, layer by layer, into a three-dimensional design.