Light shades on jeans are becoming a fashion trend for the next season. To wash down original dark blue color from indigo into lighter fashionable shades, it has been applied a bleaching process that requires high quantities of sodium hypochlorite, a toxic chlorine containing oxidising agent or potassium permanganate, and pumice stones and sand blastings as well as other mechanical processes like brushing and other abrasive alternatives for bringing down the color, both harmful to workers’ health and the environment.
Besides jeans, H2DENIM technology can also be applied on materials other than denim, such as knitwear tops, and with other more sensitive fibers.
H2DENIM is a simple short process that does not need reduction nor oxidation.The dispersion is stable and homogeneous, something that cannot be achieved using indigo alone. It is then ready to be applied by an exhaustion process, using a proprietary fixing agent. It is a simpler process and level colors are obtained on fabric or garment dyeing.
Dyeing is performed at 60ºC for 1 hour at neutral or weakly basic conditions, followed by 2 rinses of 10 minutes each, at a liquor ratio of 1:10, at room temperature, and then proceed to washing to wash-down the excess indigo. Process for a mild washing effect is in washing machine with the abrasion caused by the tumbler of the machine itself.
Enzymes or other methods for washing-down colour may be used if necessary, for stronger action. Dry in the tumble drier.
When laundering for the washed down effect on garments, indigo is very polluting. Bleaching is usually done with hypochorite to bring down the color from dark dyed indigo jeans. With the H2DENIM process, the process is a lot less polluting not needing bleaching but only friction, since light colors are obtained directly when dyeing garments.