Denim dyeing is cleaner thanks to a new partnership between chemical supplier DyStar and Indian denim mill Raymond UCO.
Raymond UCO has tested the performance of the organic reducing agent Sera Con C-RDA, offered exclusively by DyStar, which eliminates the salt in indigo dyeing. Dyeing methods that result in salt generation can cause particles that infiltrate the natural water supply and degrade the ecosystem. As a result, this innovation makes it easier to attain effluent discharge compliance, which are standards set by the Environmental Protection Agency (EPA) and other international agencies to keep harmful waste out of the world’s water.
DyStar’s reducing agent works with its Cadira Denim system, a dyeing process launched in 2017 that combines DyStar Indigo Vat 40% Solution with Sera Con C-RDA. Touted as the “cleanest indigo on the market,” DyStar Indigo Vat 40% Solution reduces sodium hydrosulfite usage by 60 percent to 70 percent.
Raymond UCO, which currently uses the Cadira Denim system in its newest collections, confirmed the results in a series of trials.
According to Katie Tague, Raymond UCO’s vice president of denim development and sales, the partnership with DyStar was a natural choice. The Cadira Denim system reduces the load on the effluent treatment process, which at Raymond UCO is 100 percent biological with zero liquid discharge. Tague noted that its water recycling standards—and sustainability efforts in general—have always been high.
“Sustainability has been in Raymond UCO’s DNA from the very beginning,” she said. “We hope to continue pushing the boundaries of what can be done.”