The first pair of jeans was patented in 1873, and the practical workwear soon became a fashion mainstay. Billions of pairs are now sold each year, comprising a market valued at over US$90 billion. Researchers from the University of Georgia (UGA), Athens, GA/USA, have developed a new indigo dyeing technology for jeans that is more environmentally friendly. The new technique reduces water usage and eliminates the toxic chemicals that make the dyeing process so damaging. Furthermore, the technology streamlines the process and secures more color than traditional methods.
Indigo, the traditional dye for blue jeans, is not water soluble and has to be reduced with toxic chemicals prior to using it to dye clothing. It takes between 50-100 l of water to dye just one pair of jeans. The new method of dyeing uses natural indigo (though the streamlined process could also use synthetic) and eliminates the use of harmful chemicals used in conventional methods. It also requires only one coat of the indigo to secure over 90% of the color, significantly reducing the amount of water needed to dye the fabric. Conventional methods require up to 8 dips in dye solution and secure only 70-80%.
The new method also keeps around the same levels of thickness, weight gain and flexibility in the fabric. Because of the streamlined process, it saves workers time and energy by eliminating the need for multiple dips and oxidation time between each dip.
Moreover, the technology mixes indigo particles with cellulosic nanofibers and then deposits them on the surface of the textile, essentially “gluing” the color in place.