Environmentally friendly laser-etched denim better than bleaching
12 December 2018
Carbon dioxide laser etching a viable green technique for distressed denim
Distressed denim can be produced to a high standard without harming the planet, thanks to an environmentally friendly, chemical-free laser etching method, according to researchers at Manchester Metropolitan University.
Scientists from Manchester Fashion Institute and the School of Healthcare Science have rigorously tested the method and verified that a carbon dioxide laser can create high quality faded and patterned denim effects, altering the colours of the fibres by vaporising the dye – without compromising the strength, colour, or quality of the material.
This means that fashion manufacturers could avoid traditional bleaching techniques – which can be disastrous to the environment – with no negative impact on the final fashion product, such as jeans and jackets.
Currently, faded or distressed denim effects are achieved industrially using a range of physical, chemical and mechanical finishing methods that can pose severe risks to the planet and to the health of people working in and living around fashion manufacturing centres.
The process is also extremely wasteful, consuming large amounts of water, electrical power, and bleaching chemicals.
Carbon dioxide laser etching
This revolutionary carbon dioxide laser etching technique can produce fading effects on a wide range of denim products – from shirts and jackets to shorts and jeans – just as effectively as with traditional methods, and without affecting the technical performance of the fabric, the study published in the Journal of Optics and Laser Technology shows.
The laser is also capable of consistently producing high-resolution half tone images on the denim, offering designers the opportunity of adding bespoke faded designs, patterns or writing on fashion items.
Dr Prabhuraj Venkatraman, Senior Lecturer in Textile Technology from Manchester Fashion Institute, said: “We are very pleased with the findings using a carbon dioxide laser, which can produce consistent design patterns on denim that meets the consumer’s expectations, influences fashion industry practice, and does not pose health risks.
“This method has a huge impact on reducing the consumption of energy, time, pollution, effluents and waste currently produced using traditional techniques.”
The interdisciplinary research team at Manchester Met applied the carbon dioxide laser to denim fabrics, and analysed the nature of the dye in the denim, the thermal degradation and changes to the chemical composition of fibres.
They examined the fabric strength, colourfastness, and air permeability of the denim fabrics after the laser was applied, finding that there was minimal degradation of fibres, and that the technical performance of the fabric was not affected.
They also determined colour changes at various levels of laser power and intensity, to find the optimal settings for a stylish design and strong, wearable fashion.
Dr Christopher Liauw, a Senior Lecturer from the School of Healthcare Science, said: “Working with Prabu on this subject was very exciting, and I can immediately see the environmental, technical and artistic benefits of vaporising the dye with a laser, rather than bleaching or rubbing it away.
“I really enjoyed applying my polymer degradation and thermal analysis expertise to this project – which I anticipate will be highly influential in the apparel industry.”
More than sixty percent of world clothing exports are manufactured in developing countries (according to the International Labour Organization), where the health of millions of people is potentially affected by unsustainable production methods, such as the chemical and mechanical finishing methods widely used to create distressed denim.
The research is published in the Journal of Optics and Laser Technology.