December 1st news, it is reported that the team of Professor Wu Dezhi from the School of Micro- and Nanotechnology at Xiamen University has made an important breakthrough in the field of 3D printing technology - innovatively proposing the "laser in-situ induced direct writing printing" technology, which significantly shortens the curing time of thermoset materials three-dimensional flexible devices from dozens of hours required by traditional processes to 0.25 seconds, effectively solving the core problems of slow molding speed, complex process, and difficult precise regulation of performance in this field.
Thermal solid materials (such as polydimethylsiloxane) are widely used in flexible electronics and biomedical fields due to their excellent flexibility, chemical stability, and biocompatibility. However, traditional templating methods and existing 3D printing technologies often encounter issues such as long curing time, the need for additional support structures, cumbersome post-processing steps, and difficulty in online regulating performance when manufacturing such devices. Even with the use of field-assisted printing techniques, challenges such as low curing efficiency and limited material compatibility still exist.
Xiamen University team created a laser direct writing printing technology: accelerating the curing of thermal solid materials by 50,000 times
The research team innovatively coupled laser with 3D printing jet, and utilized the laser to illuminate the micro-scale jet generated locally by the photothermal effect, which can heat the material temperature to 150~300℃ in an extremely short time, thus inducing the thermosetting ink to complete crosslinking and solidification instantly, greatly improving the manufacturing efficiency.
The technology also has excellent structural shaping capabilities, allowing for the high-precision printing of complex three-dimensional structures such as large-inclination, horizontal, and spatial curves without the need for support materials. The structural resolution can reach 50 microns, and the aspect ratio of three-dimensional structures can be as high as 50, enabling the stable printing and manufacturing of large-span, slender devices. In addition, by regulating process parameters in real time, the technology can also achieve continuous programmable regulation of material mechanical and electrical properties within a range of 10 to 20 times.
At present, the team has successfully prepared stretchable electronic devices with gradient stiffness, high-sensitivity flexible pressure sensors, and high-performance three-dimensional magnetic-driven soft robots by using this technology, which can be widely used in smart wearable devices, human motion monitoring, and precision driving, etc.
It is worth mentioning that the technology shows good compatibility and extensibility with a variety of thermosetting materials (including various silicone rubbers, epoxies, polytetrafluoroethylene, polyurethanes, and polyimides, etc.), demonstrating strong industrialization potential and is expected to promote the 3D printing technology in the fields of flexible electronics and intelligent soft robots to achieve large-scale application.