A newly developed photonic fibre could be used to label clothing for easier recycling
Spotted: Around 92 million tonnes of clothing and textiles are thrown away each year – and only around 15 per cent of this waste is recycled. One of the reasons for this low recycling rate is the fact that textiles are often composed of different materials, making them difficult to sort. Although many recyclers use near-infrared sorting systems that can identify materials according to their optical signatures, these systems are not efficient at sorting blended fabrics. Now, a research team at the University of Michigan has come up with a possible solution.
The team has developed woven-in labels made with photonic fibres that act like a barcode woven into the garment. The team started with a plastic feedstock, which is heated and pulled to form thin strands that can be woven into clothing. The combination of the materials bends and refracts light to create optical effects that can look like different colours. It’s the same basic phenomenon that gives butterfly wings their colours.
By adjusting the mix of materials and the speed at which the feedstock is pulled, the researchers can ‘tune’ the fibres to create different optical properties. The result is an optical signature that can be read with existing systems and can very precisely tell recyclers the exact composition of a fabric.
Although manufacturing the photonic fibres is more expensive than making the traditional ones used in textiles, the researchers estimate that it will only increase the cost of finished goods by a small amount.
The fashion industry contributes up to 10 per cent of global emissions, making improvements in the industry’s carbon footprint imperative. Springwise has spotted a less toxic dyeing process using biopigments, and a zero-waste wool made from recycled fibres.
Written By: Lisa Magloff