# Northwestern engineers build DIAL 3D printing: thick inks cured by light, grids over four times faster

- Published: 2026-11-13 17:19 UTC
- Section: Machines & Making › Manufacturing
- Tags: direct ink additive lithography, DIAL 3D printing, light-based 3D printing, direct ink writing, slot-die nozzle, structural electrolytes, hydrogel printing, Northwestern University engineers, Science Advances, support-free printing
- URL: https://realtech.media/news/rt-2b2aecb06aa87dab0e3c50b4_northwestern_engineers_build/

**The DIAL method spreads paste-like ink into 50-micron sheets and cures them with patterned light, printing porous grids over four times faster than extrusion.**

![Northwestern engineers build DIAL 3D printing: thick inks cured by light, grids over four times faster](https://realtech.media/media/2026/11/fb68145fb5b319b2.jpg)
*Adoscam, Wikimedia Commons, CC BY-SA 4.0*

Engineers at Northwestern University have developed direct ink additive lithography, or DIAL, a 3D printing method that combines the speed and precision of light-based printing with the broad ink compatibility of extrusion. The study is published on November 4 in the journal Science Advances, according to eurekalert.org [1]. Ryan Truby is the senior author; Pranav Kaarthik is the lead author [1].

Until now, users had to trade off between speed, fine features and material choice. Light-based printers are fast and precise but generally need thin, free-flowing resins that let light pass through. Extrusion techniques such as direct ink writing handle many inks, but they draw an object one line at a time, and the fine nozzles needed for detail clog easily [1].

## How DIAL builds a part

The printer first deposits thick, paste-like ink through a long, narrow slot-die nozzle onto a flat surface. A blade then spreads it into a uniform sheet 50 microns thick, thinner than a human hair. A projector shines patterned light onto the sheet and hardens the selected areas. The cycle repeats layer by layer until the object is complete [1].

Because whole regions are hardened at once, printing is faster than line-by-line extrusion. Resolution depends mainly on the projector's pixel size and the layer thickness, not on nozzle size [1]. DIAL can also print thick, particle-filled inks, including those that scatter light [1].

The ink itself supports overhangs, so free-standing structures need no co-printed scaffolding [1]. According to the publication bioengineer.org, the team made such an ink by compounding a light-curable resin with fumed silica nanoparticles to give it a yield stress.

## Test results

In side-by-side tests, DIAL printed porous, grid-like structures more than four times faster than conventional extrusion printing, with sharper features and fewer defects [1]. It also printed delicate lattices that extrusion could not reproduce and that a desktop light-based printer could make only with additional supports [1].

To show material range, the team printed intricate structures from two functional inks: structural electrolytes being developed for batteries, and hydrogels inspired by laboratory devices for growing cells and engineering tissues [1].

Truby said DIAL can produce parts that have been challenging if not impossible to make with other 3D printing methods [1]. The authors name structural applications, robotics, energy storage, tissue engineering and custom medical devices as possible areas of use [1].

## Sources

1. [eurekalert.org](https://www.eurekalert.org/news-releases/1150529)
2. [bioengineer.org](https://bioengineer.org/hybrid-3d-printing-method-combines-speed-with-thick-functional-inks)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-2b2aecb06aa87dab0e3c50b4_northwestern_engineers_build/