APPLICATIONS
TPU Material
TPU (Thermoplastic Polyurethane Elastomer)
TPU is an elastomer material with unique elastic properties, which is different from the other three rigid materials. It combines the elasticity of rubber and the processability of plastic, making it especially suitable for UV molding of flexible, stretchable, and three-dimensional embossed microstructures. TPU has good wear resistance and weather resistance, as well as excellent impact resistance and oil resistance, making it suitable for outdoor and special environment applications.
The hardness of TPU is adjustable in a wide range (55A-72D), which can be flexibly selected according to different molding requirements. Its microstructure replication accuracy is medium-high (micro-scale), but due to its elastic characteristics, there will be slight deformation at the edge of the replicated microstructures, so it is not suitable for nano-scale precision applications. In terms of UV curing compatibility, TPU has a polar surface, with a surface energy of 45-55mN/m, and good adhesion to UV glue.
When using TPU, special attention should be paid to its demolding performance. Due to its high viscosity, the mold needs to be mirror-polished (Ra≤0.8μm) or coated with silicone-based release agents to avoid sticking to the mold. In addition, the shrinkage rate of TPU is unstable (0.5-3%), which decreases with the increase of hardness, so mold pre-compensation is required during the molding process. TPU also needs to be fully dried before use; otherwise, bubbles will easily be generated during UV curing, affecting product quality.
