UV protection afforded by textile fabrics made of natural and regenerated cellulose fibres

In the last decades the media have highlighted the ozone depletion as major environmental problem resulting in an increase in ultraviolet radiation (UVR) reaching the earth's surface. Besides the beneficial effects of human exposure to UVR, this radiation is capable of causing damage to human population. The healthy lifestyle is becoming widely accepted by the public, and the UV protection provided by clothing becomes the significant subject of interest of the producers and consumers of textile fabrics. Natural cellulose fibres are commonly used in summer clothing due to their excellent comfort properties. However, these fibres have very poor UV protection ability. In this project, the UV protection property of textile fabrics made of natural and regenerated cellulose fibres have been compared and analysed in order to highlight the potential of hemp fibre for the development of more sustainable and healthy functionalized (UV protective) textile products. A group of homogeneous and blended cellulose textile fabrics were manufactured in a knitwear factory, evaluated in terms of the structure, and spectrophotometrically assessed to indicate their UV protection ability. The knitted fabrics merited sun protection ratings of "good" for pure hemp, through "very good" for viscose containing fabrics to "excellent" UV protection category for cotton based fabrics. Relatively high values of the Ultraviolet Protection Factor (UPF) of the cellulose. materials resulted from the interaction of fibre type, yarn geometry, fabric properties and common processing techniques. The increased UVR transparency of the pure hemp fabric, which resulted from hemp elasticity limitations, overcame by blending with other softer and more elastic cellulose fibres (cotton, viscose). The engineering approach proposed in this study was confirmed as an effective way to create more sustainable (more sustainable resource, pollution prevention, energy and cost savings) textile products with high level of UV protection at the knitting production stage avoiding the use of any additional mechanical and chemical treatments. These results revealed that the future application of hemp fibres in textile products with high added-value are promising. A co-ordinated effort of different subjects of the agro-and textile-industry production chain need to continue so as to overcome the limitations associated with hemp production and fibres properties. (C) 2019 Elsevier Ltd. All rights reserved.