A new 3D-printing technique could render a three-dimensional object in minutes instead of hours—at up to 100 times current speeds. The experimental approach uses a vat of resin and some clever tricks with UV and blue LED lights (no lasers needed) to accelerate the printing process.

The technique looks almost like a time-reverse film loop of an object dissolving in a reservoir of acid. But instead of acid, this reservoir contains a specially-designed resin that hardens when exposed to a particular shade of blue light. Crucially, that hardening (the technical term is polymerization) does not take place in the presence of a certain wavelength of UV light.