Scientists at ETH Zurich and a US startup from MIT have used 3D printing technology to create a robotic hand with bones, ligaments, and tendons made of different polymers. The polymers used can replicate the elasticity and rigidity of a human hand, making them more advanced than existing 3D-printed prosthetics. The technology allows for the printing of slow-curing plastics, which have enhanced elastic properties and are more durable and robust. The use of slow-curing polymers was made possible through the development of new technology by the researchers. The technology also allows for the easy combination of soft, elastic, and rigid materials.