3D printing has long forced a trade-off between speed, fine detail and the materials you can use. On November 4, 2026, Northwestern Engineering researchers described a method that tries to remove it. Called direct ink additive lithography (DIAL), it was published in Science Advances and announced in a Northwestern Engineering news article.
The trade-off DIAL targets
Direct ink writing works like squeezing toothpaste: thick inks are pushed through a narrow nozzle, one line at a time. It handles many materials but is slow, and tiny nozzles clog, so resolution suffers. Light-based printing projects patterned light onto liquid resin to harden whole regions at once, which is faster and more precise, but it generally needs thin, free-flowing, light-transmitting resins.
How DIAL works
A slot-die nozzle deposits thick, paste-like ink onto a flat surface. A blade sweeps across it, spreading a smooth sheet just 50 microns thick, thinner than a human hair. A projector then shines patterned light that hardens chosen areas. The cycle repeats layer by layer. Because resolution depends on the projector’s pixel size and layer thickness rather than nozzle size, fine detail is possible, and the method can use thick, particle-filled inks, even ones that scatter light.
The ink doubles as support. The team mixed light-curable resin with fumed silica nanoparticles, giving it a yield stress, like toothpaste or cream cheese: it flows under the blade, then stiffens again. Unhardened ink holds delicate overhangs in place, so no separate scaffold is needed. Afterward the leftover ink is washed away, and excess ink on the print surface can be reused.
What they printed
- A porous grid in 30 minutes, versus 124 minutes with conventional extrusion, more than four times faster.
- Lattices with walls as thin as 150 microns, which extrusion could not make, plus interlocking chainmail.
- A honeycomb spanning an area nearly four times larger than the projector’s illumination area, by moving the projector across overlapping sheets. Since DIAL does not use a vat, the team expects larger build areas to be easier than with most light-based methods.
- Fifteen porous lattices, about the size of small coin-cell batteries, in one 15-minute run, using a structural electrolyte ink made from a polymerizable ionic liquid. This could eventually support new energy-storage devices.
- Hydrogel containers modeled on cell culture inserts, with arrays of microscopic inverted pyramids like surfaces used to grow cells and organoids.
What’s next
Senior author Ryan Truby, an assistant professor at Northwestern, said printing such materials needs new software, hardware and inks working together. His lab is now working on materials for extreme environments such as space travel, flexible robot body parts, medical devices and tissue culture environments for biomanufacturing. The team expects faster print times by streamlining how DIAL switches among tools.
Practical takeaways
- Printing thick, functional inks with light-level resolution widens the materials available to engineers.
- Support-free printing cuts waste and avoids damaging delicate features during scaffold removal.
- These are lab demonstrations; commercial availability was not announced.
Bottom line
DIAL borrows the best of two printing worlds. If it scales, expect it in batteries, robotics and tissue engineering research first.