Improving UV Protection of Cotton Fabrics through Digital Textile Printing

Protection of the skin from harmful UV rays is an important consideration in the selection of fabrics for outerwear because of the rise in cases of skin cancer. Fiber composition, fabric porosity and color can significantly affect UV blocking properties. Digital textile printing is a unique method of coloration of textiles whereby fabric preparation parameters can be manipulated to improve the application of ink to maximize the coating effect of the inks. Ultraviolet Protection Factor (UPF) of a fabric provides a quantitative assessment for the amount of UV radiation blocked. Our study aimed to improve UPF of cotton fabrics by application of colorants via inkjet printing process and manipulation of structural change of the fabric to reduce fabric porosity and hence increase their UV blocking properties. Two major colorants were investigated to compare the performance of the printed goods in terms of their UV blocking property. Cotton fabrics were printed with piezo technique based ink jet printers: Mimaki GP 604 (pigment based inks) and Mimaki TX-2 (dye based inks). Four process colors Cyan, Magenta, Yellow and Black (CMYK) were selected to investigate individual color performance. UPF values of the printed goods and control fabric were measured by UV Transmittance analyzer according to the AATCC test method 183-1999. All the printed and control fabrics were examined for their structures using SEM which revealed changes in the fabric porosity during printing process. This study provided valuable information on UV blocking property of digitally printed cotton fabrics to textiles professionals, designers and, customers.