Sustainable Screen Printing of Cotton Using Bio-Paste from Sandalwood and Chamomile

Background In the present scenario of the textile industry is contributing significant environmental pollution for the use of different types of synthetic dyes which are mainly toxic, non-biodegradable, and use a lot of resources. As a result, there is a growing demand of natural dyes which can be a sustainable alternative because it offers eco-friendly and health-conscious solutions for textile colorations. Method This research highlighted the use of binary natural dye paste extracted from red sandalwood ( Pterocarpus santalinus ) and chamomile ( Matricaria chamomilla ) for the screen printing of cotton fabric. The dye was extracted using microwave treatment and the process was optimized using statistical design through central composite design (CCD) under response surface methodology. The printing variables was the concentration of plant powder (1-6 g), amount of thickener (1-8 g), pH (7-12), and the irradiation time for microwave rays (1-4.2). The concentration of the both chemical (Al³ + , Cr³ + , tannic acid) and bio-mordants (pomegranate, myrobalan, red sumac) were 0.5-1.5%. The final printed fabrics were checked using different tests including color strength (K/S), colorfastness (ISO standards), antioxidant, and antibacterial properties. Results The optimization conditions were observed using 2.5 g each of red sandalwood and chamomile, 2.5 min microwave treatment, 4 g thickener, pH 9 with the high color strength (K/S) value of 4.71. Both mordanting conditions, including chemical and bio-mordant, showed good colorfastness properties where the bio mordants had the outstanding performance due to the avoiding of heavy metal pollution. The printed cotton fabric also showed strong antioxidant activity up to 89% and higher antibacterial efficacy against Staphylococcus aureus and Escherichia coli , particularly using microwave treatment. Conclusion As a result, the combination of binary plant extract can be effectively used as an alternative of synthetic dyes for the ecofriendly screen printing of cotton fabric. The combination of statistical analysis, microwave treatment for natural dye extraction and use of bio-mordants are the alternatives of sustainable solutions which will reduce the reliance on synthetic dyes.