Fast, precise 3D printing seamlessly merges soft/ hard properties into object without failure at the interface, using different colors of light

https://www.eurekalert.org/news-releases/1088953

"liquid resins/ dual-light printing activates different chemical reactions depending on color of light used, violet = stretchy/ UV = rigid...  speed up 3D printing with built-in material control... enables flexible/ strong, complex output... at interface, molecule with both reactive groups enables much stronger connection between soft/ hard parts, can be gradual transition if we want... soft parts stretched/ bounced back, hard parts as strong as consumer products' plastic... prosthetics, flexible medical devices, stretchable electronics"