Digital Light Processing (DLP) is a high-resolution, high-speed additive manufacturing method that builds 3D parts by selectively curing photopolymerizable resins layer-by-layer. To achieve multi-color DLP printing, researchers have used multiple switchable resin vats. However, these methods require complex vat switching devices and cleaning manipulations, leading to low efficiency. Therefore, it remains a challenge to achieve multi-color DLP 3D printing efficiently.
In this work, Qi and his collaborators realize a single-vat multi-color DLP 3D printing by using an anthraquinone-based dye. The dye can be oxidized by the free radicals released from photo-initiators under UV light and change the color from blue to yellow. This color-changing mechanism permits a graded spectrum of colors as concomitants of photo-polymerization process during DLP printing by controlling the light dose, without using extra vats or devices. To demonstrate the versatility and efficiency of our multi-color DLP, multi-color demonstrations, such as engineering stress simulation results in 3D, and multi-color vases, were successfully fabricated. This novel strategy can be extended to sensitive dyes with different colors to further expand the range of colors and find potential applications in the 3D printing industry.
Single-vat multi-color DLP 3D printing is realized by an anthraquinone-based dye. The dye can be oxidized by the free radicals released from photo-initiators under UV light and change the color from blue to yellow. The change of color can be controlled by the light dose with grayscale slices, without using extra vats or devices. Multi-color demonstrations, such as engineering stress simulation results in 3D and multi-color vases, are successfully fabricated, showing great versatility and efficiency.
This work was conducted by Prof. H. Jerry Qi’s group at Georgia Tech in collaboration with Prof. Raheem Beyah of Georgia Tech, Drs. Chunliang Lu and Chieh-Min Cheng of Xerox Corporation, and Prof. Ruike Zhao of Stanford University. The first author is Mr. Xirui Peng.
Further information on this work could be found in the recently published article in the following link:
https://doi.org/10.1002/adfm.202112329
Peng, X., Yue, L., Liang, S., Montgomery, S.M., Cheng, C.M., Beyah, R., Zhao, R., Qi, H.J., 2022. Multi-color 3D Printing via Single-Vat Grayscale Digital Light Processing. Advanced Functional Materials, 2112329.