Germany’s BASF has launched orthopaedic insoles with Elastollan, BASF’s thermoplastic polyurethane (TPU).
The duro3D paver uses the TPU as a filament.. In the production of individual shoe insoles using 3D printing processes. In sole applications, the material vibrates and absorbs shock exceptionally well due to its superior vibration damping and resilience.
The production of shoe soles made of TPU filaments enables complete and comprehensive recyclability. Under heavy use, when used in sports shoes, it is also the abrasion resistance that makes the sole durable. And comfortable to wear. Even with fluctuating temperatures, the insert retains its desired properties. An excellent matching of the thermoplastic material to the challenges of discontinuous extrusion in 3D printing (FDM). Makes it possible to map macrostructures of different densities in a sole, which in turn are – also selectively. Tailored to very individual needs. Thus, soft sole areas with lower filling density can relieve and flow smoothly into another area, which rather firmly supports and stabilises the foot with higher filling density, the company said in a press release.
The Elastollan types with a Shore A hardness of 95 and a Shore A softness of 85 are commonly used in orthopaedic insoles to provide support for the entire skeleton.
But also in insoles for sports shoes, where a special load cushioning or support is desirable due to increased footwork. The open grid structure of the material also makes the sole breathable. Through the so-called smoothing, by the production of flowing, linear transitions between two hardness areas of the sole. The width of the transition area is customizable to avoid unpleasant hard edges.This fully demonstrates the full application flexibility of Elastollan.
The production of shoe soles made of TPU filaments enables complete and comprehensive recyclability. In contrast to commercially available milled soles made of foam materials. During the use cycle, we can mechanically shred, re-extrude, and granulate the material after its use.A recycler combines used deposits with production surplus by type and completely recycles them. By making the insoles to measure, material is massively saved. Only the final required material is used. As a result, there is almost no surplus in production. A production of the soles with thermoplastic polyurethane based on renewable raw materials is also conceivable in principle.