This radiation is mainly composed of infrared light. It leads to a loss of energy and therefore to a cooling of the human body. The viscose fibre with incorporated IR-reflecting particles by Kehlheim Fibres can significantly reduce this process: Thermal radiation emanating from a body is reflected by the particles incorporated in the viscose fibre and sent back to the body, so reducing the cooling of the person.

In addition to this thermal retention function, the wearer of such a textile also benefits from the typical properties of a viscose fibre such as wearer comfort, softness and skin friendliness. This is achieved by the intrinsic quality of the treatment: in contrast to a subsequent finish with additives based on titanium oxide, the mineral IR-reflecting particles are incorporated into the fibre’s core, preserving the typical fibre properties. The effect is permanent as the additive cannot be washed out. Test results of the new fibres show significant temperature effects in comparison to a standard viscose fibre.

This opens up a multitude of possible fields of applications: Used in functional underwear, the thermal effect can increase the well-being of the wearer even at low temperatures. In functional sportswear, the new fibre can lead to improved performance and a faster regeneration of the athlete, thanks to improved blood circulation. Along with textiles, different nonwoven applications could benefit from the IR-reflecting fibre, as for example warming shoe inserts.

„Comfortable feel-good clothes and functional special clothing are just two obvious applications for our IR fibre”, so Dr. Nina Köhne from Kelheim Fibres’ R&D team. And her colleague, Dr. Daniela Bauer, adds: “We would be happy to adapt the fibre exactly to the demands of other applications depending on our customer’s specific needs. In the past, individual development partnerships often have proven very fruitful and we are glad when our customers reach out to us with their new ideas.” For the next step, the Bavarian fibre specialists are planning physical and physiological textile tests.

Kelheim Fibres GmbH is the world’s leading producer of viscose speciality fibres and the most important supplier of viscose fibres for the tampon industry. Approximately 90,000 tons of viscose fibres are produced and tested every year at Kelheim in South Germany. These are used in most diverse applications – from fashion, hygiene and medical products to nonwovens and speciality papers. Innovative products, flexible technologies and a strong customer orientation form the foundations of the company’s success.