Physicochemical properties of banana leaves at different growth stages: Effects of bleaching and natural dyeing with lac, butterfly pea, and turmeric

• Bleached banana leaves contain five key elements: carbon (C), oxygen (O), silicon (Si), phosphorus (P), and potassium (K). • The moisture content of bleached banana leaves ranges between 11.98% and 15.50%, with decreased thickness and opacity compared to fresh leaves. • Color values show an a* value in the red direction and b* value in the yellow direction, influencing their suitability for natural dyeing. • Six-month-old banana leaves were found to be the most suitable for dyeing, producing dark red with lac, blue green with butterfly peas, and orange yellow with turmeric. • Naturally dyed banana leaves can be utilized as eco-friendly materials for crafting creative products, such as bags of various shapes. This research aimed to study the impact of bleaching and natural dyeing on the physicochemical properties of banana leaves at various stages of growth. Banana leaves were bleached and dyed using three natural dyes: lac, butterfly pea, and turmeric. The bleaching process reduced the moisture content from 66.05% to 11.98%–15.50% and decreased the thickness and opacity of the leaves, while glossiness was not significantly affected. EDS analysis identified carbon, oxygen, silicon, phosphorus, and potassium as the five main elements present after bleaching. The color values of the leaves changed noticeably; the a* value shifted toward red, and the b* value toward yellow. Six-month-old banana leaves were found to be most suitable for dyeing due to their structure and dye absorption properties. When dyed, lac produced a dark red tone (L* = 61.14, a* = 3.95, b* = -2.90), and butterfly pea yielded a blue-green shade (L* = 62.40, a* = -1.00, b* = -4.60), and turmeric resulted in an orange-yellow hue (L* = 68.41, a* = 8.79, b* = 7.19). These findings suggest the potential of using naturally dyed banana leaves as sustainable, biodegradable materials for creative product design, particularly in eco-friendly fashion and lifestyle items such as handbags and backpacks.