Swiss textile chemicals specialist, Archroma, has teamed up with Stony Creek Colors of Springfield, Tennessee, to develop and commercialize IndiGold, a high-performance plant-based pre-reduced indigo.

IndiGold was developed with Archroma to offer the first-ever plant-based alternative to synthetic pre-reduced indigo. Stony Creek extracts its dye from proprietary Indigofera plant varieties grown in partnership with family farms as a regenerative rotational crop, and IndiGold was developed with Archroma to offer the first-ever plant-based alternative to synthetic pre-reduced indigo. The dyestuff will be supplied in a soluble liquid form with a 20% concentration that performs similarly to other synthetic indigo products on the market.

Due to the comprehensive development of an improved agricultural value chain, from seed breeding and production to biomass collection and extraction, Stony Creek has evolved into a leader in plant-based indigo. Since 2015, the company has begun selling indigo cultivated in the United States to denim factories.

The pre-reduced plant-based indigo collaboration began in 2020 when Stony Creek was looking for like-minded partners to help them scale up the production of the new dyestuff. Archroma proved to be the right partner, as it is well-known for its indigo manufacturing and application skills.

Archroma has consistently introduced environmentally improved indigo innovations, such as the first aniline-free synthetic pre-reduced indigo and the Archroma x CleanKore technology for aniline-free potassium permanganate-free spray and white abrasion laser booster.

It then provided comprehensive pilot-scale manufacturing trials to Stony Creek, as well as engaged with its network of denim machinery makers to evaluate the first samples in industrial conditions. As with synthetic indigo, the testing revealed good coloration and the typical indigo washdown. Archroma plans to manufacture the initial batches of IndiGold in Salvatierra, Mexico, and has other locations in mind. Its manufacturing and logistical skills, as well as its expertise in denim dying with clients utilizing pre-reduced indigo, will help Stony Creek.

Stony Creek was chosen as an innovator in Fashion for Good's global Innovation Programme, which connects companies with innovators to collaborate on testing, validating, and ultimately scaling disruptive technologies in the fashion sector. Fashion for Good has partnered with Levi Strauss as part of the program, and will now pilot the usage of IndiGold in denim mills at scale, with the goal of uncovering critical learnings about shade application and other efficiencies of this novel dyestuff.