# Application of PolyJet 3D Printing in Production of Flexographic Printing Plates
###### Abstract  
The aim of this study was to investigate whether PolyJet technology, which uses rubber-like materials for printing and is known for its high resolution and performance, could be suitable for producing flexographic printing plates. In our research, we designed test plates that were printed using PolyJet technology with TangoBlackPlus FL39870-DM resin. These 3D-printed plates were evaluated for their resistance to various flexographic links and solvents, and their contact angles were measured. Subsequently, the prints were made on a Flexiproject device using water-based ink with both the test plates and traditional photopolymer plates across six different substrates. The print quality was assessed using densitometry and spectrophotometry. Our findings indicate that the 3D-printed plates are suitable for printing solid areas and lines with water-based inks. However, the print quality of the 3D-printed plates is slightly lower than that of the photopolymer plates, with the optical density values for the high-quality prints on coated papers being approximately 10% lower. Additionally, the plates printed with TangoBlack Plus resin appear to be suitable for UV inks due to their high resistance, but they are not resistant to the solvents used in solvent-based inks. additive manufacturing; 3D printing; PolyJet; flexographic printing; printing plates; prints quality +
Footnote †: journal: Applied  
(DLP), Continuous Liquid Interface Production (CLIP), PolyJet (PJ), Multi-Jet Printing (MJP), Fused Deposition Modeling (FDM), Fused Filament Fabrication (FFF), Direct Ink Writing (DIW), Selective Laser Sintering (SLS), Multi-Jet Fusion (MJJF), and Laminated Object Manufacturing (LOM), [11; 21; 22]. Some of these AM techniques, including SLA, DLP, CLIP, PJ, MJP, DIW, and FDM/FFF, allow for the printing of flexible designs using rubber-like materials [14]. In addition, Vat Photopolymerization (VPP) processes (which include SLA, DLP, and CLIP) and Material Jetting (MJT) processes (which include PJ and MJP) use liquid polymer compositions with a wide range of resins to create models. Flexographic printing plates, due to the deformation that occurs during ink transfer from the printing plate to the printing substrate, are made of flexible materials for precisely this reason [23; 24]. Considering printing resolution, the best results can be achieved with the MJT and VPP processes. The resolution for MJT ranges from 10 to 28 \(\upmu\)m, while for VPP, it ranges from 10 to 140 \(\upmu\)m [11]. In terms of dimensional accuracy and model deformation, MJP and PJ technologies, alongside SLA and MJF, also perform well. For MJT systems, the dimensional accuracy is \(\pm\)0.1-0.2% with a typical lower limit of \(\pm\)0.02-0.1 mm. In comparison, the dimensional accuracy for SLA and MJF is \(\pm\)0.2% with a lower limit of \(\pm\)0.2 mm [11]. Among the mentioned AM techniques, MJT technologies seem to be the most useful for preparing a flexographic printing plate. They provide the highest accuracy in the produced model and allow us to make a part with a similar hardness and flexibility to a traditional photopolymer plate. PolyJet is a variation of the Material Jetting (MJT) process developed by Obiet Geometries. The model is created from photopolymer resin and support material using ink jet print heads and fixed with UV light immediately after application [25; 26; 27]. The printed model requires post-processing, which involves the removal of supporting elements by blowing them out with compressed air or washing them out with water at a higher pressure. The undoubted advantages of this technology are the high resolution of the built parts while at the same time maintaining a high speed, the high accuracy and repeatability of the process, the wide spectrum of available materials, the clean and easy method of removing the support material, and the high simplicity of system operation [28; 29; 30].