Photo-curing 3D printing technique and its challenges

In recent ten years, 3D printing technology has been developed rapidly. As an advanced technology, 3D printing has been used to fabricate complex and high-precision objects in many fields. 3D printing has several technologies. Among these technologies, photo-curing 3D printing was the earliest and most mature technology. In 1988, the first 3D printing machine which was based on photo-curing and called Stereo lithography Appearance (SLA) technology was produced by 3D system Corp. After 30 years of development, many new technologies based on photocuring mechanism emerged. Based on the different principle of pattern formation and character of printing technology, numerous photocuring 3D printing techniques, such as SLA, DLP, LCD, CLIP, MJP, two-photon 3D printing, holographic 3D printing and so on, have been developed. Photo-curing 3D printing has many advantages, such as high precision, smooth surface of printing objects, rapid printing speed and so on. Here, we would introduce five industrial photocuring 3D printing technologies, which are SLA, DLP, LCD, CLIP and MJP. The characters of the materials and the progress of the application of the technique in the biomedical field is also overviewed. At last, the difficulties and challenges of photo-curing 3D printing are also discussed.