VALENCIA – In July this year, Spanish denim mill Tejidos Royo will be the first textile operation worldwide to take delivery of new, large-scale indigo yarn dyeing equipment that uses foam to dye indigo cotton yarns.
The new technology shortens the production steps needed to dye indigo yarns, and claims it significantly improve its environmental impact as a result.
Indigo yarn dyeing is noted for using large amounts of water, whereas foam dyeing is a water-saving technique – albeit known for many years.
Yet foam been a problem for indigo dyeing because the dye reacts with air trapped inside the foam, which stops it penetrating the cotton fibre.
Using foam blown with nitrogen – instead of oxygen – is said to overcome this problem.