Application of variothermal heating concepts for the production of microstructured films using the extrusion embossing process

The application of the extrusion embossing process is a fast and cost-effective way to produce large-scale fi lms with structured surfaces. In principle, microscopic and macroscopic surface structures can be manufactured this way. Particularly for the fabrication of microscopic structures, the reproduction accuracy can be remarkably improved by applying variothermal heating concepts for the embossing roll. In this article, two possible heating concepts are investigated: one laser-based and another using an inductor. The generated temperature profi le along the circumference of the embossing roll is studied, taking the material of the embossing roll as well as different processing parameters into account. Both external heating systems (laser vs. inductor) are tested and compared. Furthermore, the improvement of the accuracy of the replicated microstructures is examined.