Researcher of the Swiss Institute for Technology Lausanne EPFL have presented a new 3D printing technology. A model is created by rotating it in a resin bath. The basic method is similar to stereolithography and, according to the developers of the tomography, is borrowed. A laser exposes individual particles in synthetic resin and lets them become solid. However, the new technology should not take hours, but should be able to print small 3D objects in just 30 seconds. The researchers are cooperating with Readily 3D, which operates and builds the printers.
The reason for this is that models are generated by rapid rotations within the transparent cylinder filled with material. Conventional SLA resin printers pull objects out of a resin bath layer by layer. The new technology has the advantage that the printed result floats in the material and has to carry less weight. This means that various prints are possible without additional supports and some shapes that were previously hardly feasible. The researchers show several examples: a tiny, two-centimeter-long plastic cathedral shows spiers, windows and ornaments relatively accurately. It can also be used to create organic shapes such as attachments for hearing aids or organ replicas. The research team specifies the precision as 80 micrometers.
The laser, which hardens the material, is reflected by a movable DLP mirror system and thrown onto the cylinder. DLP is a technique that is also used in some projectors. However, these usually project a two-dimensional image onto a screen. A camera that is offset by 90 degrees therefore specifies the coordinates at which the exposure should also take place at depth. The material can be normal synthetic resin or soft hydro gel.
In the future, technology should help with the construction of elements in medical technology. One disadvantage so far has been that a maximum of two centimeters of pressure space is available. However, the developers want to create larger models of up to 15 centimeters in further versions. Then the technology could also be suitable for the commercial market.
Functional diagram of the new technology (Image: EPFL)