Understanding the influence of fibre, yarn and fabric parameters on UV protection of wool-knitted fabrics

This work investigated the influence of fibre, yarn and fabric parameters on the UV protection of fabrics. It proposed a model for UV interaction based on a theoretical hypothesis, targeted experimentation and statistical analysis. Undyed and untreated wool-knitted fabrics with varying mean fibre diameter, yarn linear density, yarn twist, fabric cover factor and fabric structure were examined. A statistical model was presented to report the relationship between fibre/yarn/fabric parameters and fabric UPF values. An optical model on the interaction between the UV light and a single jersey fabric was constructed to understand the penetration of UV light. The models were verified by the UV transmittance results of knitted wool fabrics. The results obtained from the statistical and optical models were used to propose a set of optimized parameters for lightweight summer/spring UV-protective knitted fabrics. Testing confirmed that these fabric parameters provided both high UV protection and good tactile comfort.