A biocidal and photoluminescent treatment of viscose fibre immediately following the addition of carbon disulfide in the conversion of cellulose into viscose (xanthation), which comprises a biocidal composition and an additive that allows the presence thereof to be identified by a luminescent effect, wherein the biocidal composition is added in an amount of 0.1-5 wt % of the material and comprises 3-5% phosphate glass with silver, 1-3.5% silicone, 0.1-0.3% aliphatic hydrocarbons and 90-95% water, and the luminescent additive is added in an amount of 0.1-5 wt % of the material and comprises 20-40% silica gel, 10-30% alumina gel, 30-50% calcium fluoride, 0.5-3% erbium (III) fluoride, 5-15% ytterbium (III) fluoride, a maximum of 5% thulium (III) fluoride and a maximum of 1% europium (III) fluoride, with respect to the total weight of the luminescent additive.

Functionalized nanofiber yarns with increased hydrophilicity with more than doubled water absorption property are provided. Methods of treatment for producing such functionalized nanofiber yarns are also provided.