2027

Sharma, Ritesh; Herrala, Mikko; Tienaho, Jenni; Haapala, Riikka; Rysä, Jaana; Tehrani-Bagha, Ali; Nousiainen, Paula

The growing demand for sustainable textile manufacturing has intensified the search for renewable alternatives to petroleum-based dyes and binders used in textile printing. However, the industrial adoption of natural dyes remains limited by poor dye fixation, inadequate durability, and the lack of bio-based binder systems capable of delivering high printing performance. In this study, a bio-based, water-borne printing paste was developed by combining a chitosan–cationic starch binder with a natural dye extracted from sea buckthorn pomace, an agricultural by-product, for screen printing of cellulosic textiles. The formulation was optimized using zeta potential, quartz crystal microbalance with dissipation (QCM-D), and rheological analyses to understand dye–binder interactions and establish suitable printing conditions. At 3% dye concentration, the biobased paste produced uniform prints with approximately twice the color strength of the commercial polyurethane-based binder (K/S = 3.07 vs. 1.53). The printed textiles also demonstrated good wash, rub, and perspiration fastness, with tactile comfort comparable to that of the commercial system. In addition, the bio-based formulation exhibited antimicrobial activity against Escherichia coli and Staphylococcus aureus, which was retained in the printed textiles after washing. The sea buckthorn dye showed no skin-sensitizing potential under the tested conditions, while cytotoxicity and oxidative stress were observed only at high concentrations. Overall, this study demonstrates that agricultural waste-derived natural dyes, combined with a biobased binder, can produce durable, multifunctional, and skin-compatible printed textiles, offering a promising platform for biobased textile printing systems with natural dyes.