Laser treatment of high-performance Kynol fibers: An example as alternative tool for coloration and imaging on surfaces of high-performance fibers

Novolac resins are used to prepare high-performance flame-retardant fibers, which are also supplied under the brand name Kynol fibers. In the current study, Kynol fiber materials are treated with a laser beam to introduce dark coloration at distinct areas on the textile surface. By this, imaging and writing on the textile surface is possible. For investigation, two different types of Kynol fiber materials are used - a non-woven fiber felt and a woven fabric. It is shown that a laser treatment of medium intensity can introduce a change to dark coloration with good rubbing fastness. The writing of letters and symbols onto fabrics is possible. However, treatments with strong laser intensity lead to significant fiber damages and low rubbing fastness. Nevertheless, the presented method is a promising tool to apply images onto flame retardant fabrics from high performance fibers, which are difficult to dye using conventional techniques of dyeing and printing.