Cellulose Nanofibril-Based Coatings of Woven Cotton Fabrics for Improved Inkjet Printing with a Potential in E-Textile Manufacturing

The roughness of woven fabrics strongly limits print quality, which is particularly critical in printing of conductive circuits on fabrics. This work demonstrates the use of wood-derived cellulose nanofibrils (CNFs) mixed with a plasticizer as coatings of woven cotton fabrics for inkjet printing using (i) conventional water-based pigment inks and (ii) conductive silver nanoparticle inks. CNFs, being similar in nature to cotton, introduced minimal alteration to woven cotton fabrics by preserving their visual appearance as well as their mechanical properties. We also showed that the use of CNF-based coatings facilitated ink droplet settling on the substrate, which ensured high quality with the potential of higher printing speed production. The coatings of CNFs plasticized with glycerol enabled concentrating the pigment on the surface of the fabric, preventing its penetration into the fabric depth, which allows for increasing the resolution of the printed pattern. When used for color ink printing, it enhanced the print chroma and permitted reducing the amount of deposited ink, yielding similar color lightness. The CNF coatings allowed for substantial reduction of the amount of silver ink when printing the conductive tracks on fabrics. Furthermore, the nature of the coating imparts flexibility to the conductive layer, while maintaining electric signal quality, even when folded. This study provides a platform for manufacturing sustainable and disposable e-textiles.