Garments dyed with a melanin-like biopolymer extracted from sewage sludge have been produced for the first time, offering a sustainable alternative to cuttlefish-derived and synthetic textile dyes. The collaboration between TU Delft and Dutch fashion label Hul le Kes represents an initial proof of concept; further testing and regulatory approvals are required before the material can enter commercial production.
- The pigment is recovered from sludge waste generated by wastewater treatment plants, converting a disposal problem into a functional textile resource.
- Beneficial properties of the biopolymer include UV protection, antioxidant activity, redox activity and metal chelation, and it can accelerate the dyeing process without the environmental harm associated with chemical dyes.
- Commercial melanin has been sourced from cuttlefish ink for years, a supply constrained by seasonal catches and complicated by ongoing ethical concerns over animal use.
- The findings have been published in 'Microbial melanin-like material: A factor beyond influencing the brown color of activated sludge', Water Research, by Yuemei Lin, Samarpita Roy and Peter-Leon Hagedoorn.
HOW IT WORKS: The paper examines microbial melanin-like material as a factor in the brown colouration of activated sludge, identifying a recovery method for extracting this biopolymer from treatment plant waste streams and documenting its application to wool dyeing as an initial demonstration of viability.
- The scope covers biopolymer recovery methodology, wool dyeing application, and a structural comparison between naturally derived and synthetically produced melanin.
- Synthetic melanin, while producible through chemical routes, differs from naturally obtained melanin in both structure and function, a distinction the research addresses directly.
- Early real-world validation came when Lin's daughter, Yiran Zhang, knitted a jumper from the dyed wool, confirming the material's performance outside laboratory conditions.
FROM LAB TO LABEL: Yuemei Lin contacted Hul le Kes directly after learning the brand had been promoted by the Dutch embassy during Paris Fashion Week for its circular and social approach to fashion. The label embraced the experiment, incorporating the new pigment into a range of garments and demonstrating that a laboratory-derived material could translate into garments that both researchers and Hul le Kes describe as looking good.
- Lin's decision to contact the label directly connected academic research to an established sustainable fashion platform with an international profile.
- The label treated the collaboration as a design exercise rather than a single test, committing the resources needed to adapt an unfamiliar biopolymer to its own aesthetic and production standards.
- The researchers have framed the designs as evidence that science and fashion can reinforce one another when working from shared material problems.
- Lin has cited the brand's openness to new materials and the effort invested in adapting the pigment to their designs as the foundation of a successful outcome.
FASHION WITH PURPOSE: Hul le Kes, founded by Sjaak Hullekes and Sebastiaan Kramer, operates at the intersection of craftsmanship, sustainability and human connection, working with upcycled and natural materials to combine historical techniques with contemporary design. The label's collaboration with TU Delft sits within a broader commitment to rethinking the fashion system through partnerships, community focus and conscious material choices.
- The brand is part of a wider movement towards a more conscious fashion system, creating space for inclusivity, mental wellbeing and gender-fluid expression through its studio and community-focused approach.
- Hul le Kes dressed Duncan Laurence, among others, during his winning performance at the Eurovision Song Contest and is known for the TV programme Genaaid, which examined the impact of fast fashion and was presented by Jennifer Hoffman.
- Hoffman and other well-known Dutch personalities regularly wear the brand's designs, extending its cultural presence beyond the studio into mainstream public life.
- Beyond TU Delft, the label is working with ReShare Store, Yumeko, Gray Label and Fibershed to develop alternatives to the current fashion system.
WHAT THEY SAID
I'm so happy that they're open to new materials and have gone to great lengths to incorporate it into their fashion designs. It has resulted in some beautiful garments!
— Yuemei Lin
Researcher, Department of Biotechnology
Delft University of Technology
