University of Utah researchers have developed a 3D printing method that forms an object in about 20 seconds, a process that can take hours using other laser-based printing techniques. The technique, described in a study published in Nature Communications, hardens an entire shape from a laser exposure rather than building it up layer by layer, which the researchers reported also avoids the leaky seams that can form between layers in conventional processes.

The work was led by Rajesh Menon, professor in the Department of Electrical & Computer Engineering at the University of Utah’s Price College of Engineering, along with lab member Dajun Lin and co-author Brian Baker of the Utah Nanofab.

How the process works

The method draws on photolithography and extends it into three dimensions. A laser passes through a light-sensitive substrate material called SU-8, hardening the exposed volume while leaving the rest to be washed away. To keep the beam accurate as it travels into the material, the team built a nanoscale mask that compensates for how the substrate bends the light, directing the laser’s energy only to the volume meant to become the finished shape.

“The mask is working like a cookie cutter, stamping a complex shape out of thick dough,” Menon said. “The laser is ‘baking’ the dough on the inside at the same time, so the resulting shape is physically tough.”

Early demonstrations and next steps

The researchers used the technique to produce microtubule assemblies with individual diameters as small as 6 micrometers, arranged in lattice patterns with dimensional ratios as high as 120:1. The structures withstood compression testing and moved liquid through capillary action. They also demonstrated printing multiple shapes in a conveyor-belt sequence.

Menon described the current output as “extended 2D” rather than true 3D, since the process controls the shape of only two dimensions while extending the third as far as possible. The team is now working to extend the technique toward genuine three-dimensional control.