Former students at Berkley University of California Michelle Zhu and Tammy Hsu, co-founders and respectively, CEO and chief scientific officer at Tinctorium, have discovered a patented method of harnessing the power of biotechnology to enable sustainable indigo production by using sugar.

 “We figured out how to mirror a natural plant process within microbes to produce colors using completely renewable sources,” they explain. “We’re the sustainable solution for the future and we’re taking on the denim industry to bring you cleaner jeans,” they continue, while explaining that they could achieve such results thanks to industry insiders’ support and in particular denim guru Adriano Goldschmied who joined the newborn company’s advisory board.

Adriano Goldschmied denim innovation advisor
Photo: AG
Adriano Goldschmied denim innovation advisor

We asked Zhu and Hsu about their discovery and how effectively it could revolutionize the denim industry.

 

When did you start researching about this new project?
The research for Tinctorium started in John Dueber's lab at UC Berkeley, where Tammy was working on her PhD in bioengineering. This project became Tammy's thesis work and she has been studying this approach for producing and applying the dye over the last six years.



What did you discover and how can you demonstrate it is truly eco-friendly?
Our technology helps to reduce the amount of hazardous chemicals used in both the dye production process and the dye application process. Currently, the production of indigo is heavily petroleum-based, often done in coal-powered factories, and relies on chemicals like formaldehyde and cyanide. The application process, which requires indigo in a reduced form, also relies on water-polluting chemicals that increase costs for materials and water treatment. We plan to work hand in hand with certification organizations and stakeholders across the value chain to measure and demonstrate sustainability as we scale. One of the challenges, of course, is running analyses in the early stages before we have a full-fledged process built out, but we're trying to find small ways to do this where possible. For example, we recently tested our dye product for the presence of the problematic petroleum-derivative and potential carcinogen aniline and were proud to find our substance aniline-free. 

 

Can you describe how your process works and differs from regular polluting ones already used in the industry?

Our solution is making indigo with completely renewable sources like sugar and microbes. We program and grow bacteria in order to secrete an indigo precursor that traps the indigo in a water-soluble state putting a pause on the indigo formation process until we are ready for the process of dyeing and then combine the precursor with an enzyme releasing the blue color thereby eliminating any need for reducing agents.

Denim dyeing process at Tinctorium
Photo: Tinctorium
Denim dyeing process at Tinctorium

Could this technique be applied to the already existing denim manufacturing process?
We've already tested the technology with a prototype industrial machine, showing that it can work as a drop-in replacement for dye mill partners we work with. There is, however, still some development work we'd like to do to further concentrate the dye to achieve even darker shade depths before we can move forward with commercialization efforts. That is our primary objective over the next few months prior to further scaling up production.


Would denim dyed with your technique guarantee the same color consistency, stability and contrasting fade-out areas as regular denim dyed with chemical indigo?
Yes, because we are not producing an alternative to indigo but rather an alternative process for making the dye in a more eco-friendly way. We should in theory be able to achieve all the same effects that the denim industry knows and loves.


Would denims dyed with your technique cost more?
Yes, particularly in the short term, as we are optimizing the technology, our dye will be a premium product, but we believe sustainability is a worthwhile investment. Because dye costs only represent a small fraction of total garment production cost, a small price increase would be insignificant to end-product cost but highly impactful for clean chemistry and highly differentiating for today's consumers. Dyes contribute to the most visible aspect of your clothing–its color–and we believe there's room to grow the market if we can help consumers understand the hazards of the dye production process today.  

 

Would this technique guarantee similar results also on other fibers than cotton like, for instance, viscose, polyester or other fibers?

Yes, for the same reason that our indigo can achieve the same expected color and fade effects, our solution can also produce comparable results on a range of fibers. Of course, all of this is testing that we plan to do as part of our development process.


Were you helped by insiders and experts in this field in discovering and transforming this new technique into an industrial base technique?

It's absolutely essential to have industry insiders to help validate an application, and I know we're going to continue to rely on the expertise of those who have spent so many years in all aspects of denim. We were fortunate to be developing the research at Berkeley in the Bay Area, where several large brands are headquartered; these brands have followed our technology and supported us with introductions to help us test our solution. Our friends at Indigo Mill Designs have been great collaborators and resources. Our advisor, Adriano Goldschmied, has been actively working to get us connected in the industry as well. We wouldn't be where we are today without the support of many of these visionaries and champions.



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