# Photopolymerization of Ceramic Resins by Stereolithography Process: A Review
## 8 Conclusions  
In this review, various aspects of the stereolithography process have been studied to highlight the peculiarities that make it ideal for the production of ceramic components. Unlike classic SLA applications, in ceramic stereolithography the basic materials are non-Newtonian fluids, therefore a previous characterization of the resins, in terms of stability, thixotropy, shear thickening-thinning behavior, allows to avoid various problems that could occur during production, such as agglomeration or viscosity increase. Extinction phenomena were presented in terms of dimensional quality and geometric precision, in particular, the importance of the difference RI between ceramic powder and monomer base was explained. In ceramic manufacturing technologies, post-treatment often includes debinding and sintering processes. The removal of the binder is the most critical step of the post-treatment, due to defects or delamination that could be generated during the evacuation of the polymer units. Sintering gives mechanical consistency to components, reducing internal and external porosity and increasing the density of parts. The solid loading of a resin base and the post-treatment processes are closely related, it is necessary to study the volumetric shrinkage of the final parts, in order to guarantee a free cracking  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Resin** & **Ceramic Component** & **Application Fields** & **Manufacturer** \\ \hline Porcelite\({}^{\text{\textregistered}}\) & Porcelain & Automotive, Aerospace, Engineering & Teflon 3D 1 \\ \hline High Alumina & Alumina & Automotive, Aerospace, Engineering & Tethon 3D \\ \hline AdmaPrint A130 & Alumina & Electronics, Medical & Admate 2 \\ \hline LithaLox HP 500/350 & Alumina & Electronics, Textile, Thermal processes & Lithoz GmbH 3 \\ \hline AdmaPrint Z130 & Zirconia & Electronics, Jewelry & Admate \\ \hline LithaCon 3Y 210 & Zirconia & Cutting tools, Metal forming, Medical & Lithoz GmbH \\ \hline C900-Flex/ALN & Aluminium Nitride & Electronics, Thermal processes & 3 DCeram Sinto 4 \\ \hline LithaNit 770 & Silicon Nitride & Electronics, Medical & Lithoz GmbH \\ \hline C900-Flex/CORD & Cordierite & Optical parts for aerospace, Metrology & 3 DCeram Sinto \\ \hline C900-Flex/HA & Hydroxyapatite & Medical & 3 DCeram Sinto \\ \hline AdmaPrint B130 & Hydroxyapatite & Medical & Admate \\ \hline \hline \end{tabular} \({}^{1}\) (Omaha, NE, United States), 2 (Alkmaar, The Netherlands), 3 (Wien, Austria), 4 (Limoges, France).  
\end{table}
Table 3: Commercial resins available in marketplace.  
component. Preparation of powder suspensions can be considered a great advantage in terms of arrangement between the geometrical capability of stereolithography processes and the obtainment of components with good mechanical or physical properties, not only for ceramic components, but also for bio-compatible materials and metals. Usage of different powder materials can open ceramic production fields to new borders of industry. An important aspect that needs to be investigated is how to make this kind of technology more sustainable, starting from chemical compounds used for resin preparation, until the analysis of the environmental impact of post-processing operations.  
Conceptualization, A.B., F.C.; Investigation, A.B.; Methodology, A.B., F.C., M.G.; Supervision, F.C., M.G., L.I.; Validation, F.C.; Writing--original draft, A.B., F.C. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The authors declare no conflict of interest.