Fabrication of visual textile temperature indicators based on reversible thermochromic fibers

Human body signals detection functions in fibers such as visual temperature indicator, are important aspects in future development of satisfying the warmth and comfortableness of conventional textile fibers. A series of reversible thermochromic fibers (VTFs), where thermochromic microcapsules and polypropylene (PP) was used as color indicator and polymer fiber matrix, respectively, were prepared via melt spinning in this paper. The temperature-color response behaviors of VTFs were investigated in detail. The scanning electron microscopy (SEM) images of cross section of VTFs showed that PP was an excellent matrix for the dispersion of thermochromic microcapsules and no aggregation occurred. The results of color measuring and matching indicated that VTFs exhibited various colors of red, purple and blue depending on the mass ratio of the red function and blue function microcapsules. Moreover, when the ambient temperature changed between 5 °C and 35 °C, the color of VTFs could fade and recover in a short time, and this kind of VTFs displayed excellent performance stability after 60 temperature cycles.