Natural Color Powder Development from Galangal Stalks for Handmade Cotton Block Printing

Abstract

This study aimed to: (1) develop natural dye powder from Alpinia galanga stems and leaves for block printing on cotton fabric, (2) examine the effects of five natural mordants—tamarind extract, ash water, vinegar, limewater, and alum, and (3) transfer the knowledge to the Ban Nam Kham Phatthana Community Enterprise Group, Phetchabun Province. Agricultural waste materials of galangal stems and leaves were extracted, dried, and processed into powder, then formulated into printing ink and applied to hand block printing on cotton fabric. Color characteristics were evaluated using the CIE Lab* system, and differences were analyzed using ANOVA and Duncan’s multiple range test. Results indicated that “galangal stem + sodium hydroxide” significantly reduced a* and b* values, producing a darker tone with reduced brightness. Mordants significantly influenced hue: ash water and vinegar produced prominent yellow tones, alum yielded a light blue tone, while tamarind and limewater resulted in light shades similar to raw cotton. The knowledge transfer workshop to the community received the highest satisfaction rating. This research demonstrates the potential to upgrade agricultural waste into creative products that sustainably support local livelihoods.