在組織工程製作生物支架上，積層製造相較於傳統製造方法擁有較快速客製化的能力。同時製作支架上也有較優異的控制能力，但是對於複雜的外型且有懸空的幾何形狀必須要有額外的支撐結構才可製作。而本研究選用冷凍成型積層製造製作水性可降解型聚胺酯以及殼聚醣支架，在支撐結構製作上以大範圍噴灑水溶液。利用水的三相變化，液態水溶液沉積至支架時將孔隙快速填充，當水溶液凝結成固態時有效的支撐。最後使用冷凍乾燥製程將冰塊昇華進而完全移除。

Building biological scaffolds in tissue engineering, additive manufacturing (AM) has ability to customize more quickly than conventional manufactured methods. In this study, we built the waterborne biodegradable polyurethane and chitosan scaffolds by frozen-form additive manufacturing, which spray the aqueous solution over a wide area on the support structure. Utilizing the three-phase change of water, the pore space was rapidly filled with a liquid aqueous solution deposited on the scaffold, effectively supported the aqueous solution as it solidified. Finally, freeze-dry process was used to sublimation the ice and then completely remove the support structure.

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