In November 2024, I had the opportunity to visit the PureDenim production facility in Inveruno, Italy, just west of Milan. PureDenim is a leading denim manufacturer known for its sustainable approaches and dedication to quality. The company, which emerged from ItalDenim in 2017, currently employs 22 people. Here are my impressions and experiences from this visit.
Why Did I Choose PureDenim as a Production Partner?
PureDenim is not a typical denim weaving mill but has reinvented itself with a focus on sustainable denim production since its inception. PureDenim works with a new concept, specializing in processes that have the greatest impact on the ecological footprint in denim production – the chemical wet processes such as dyeing and finishing. Together with technology partners, PureDenim has developed new production processes to reduce the ecological footprint of denim.
SmartIndigo: Dyeing with Electricity Instead of Chemicals
A central highlight at PureDenim is the SmartIndigo technology, which they use as the only denim manufacturer in Europe. Indigo pigments are insoluble in water. Conventional dyeing processes use the environmentally harmful and health-threatening reducing agent sodium dithionite to make indigo soluble. SmartIndigo was developed by Sedo Engineering in Switzerland and replaces dangerous chemicals simply with electricity. The indigo pigment is reduced electrochemically on-site and does not require any additional chemicals as reducing agents. This innovative dyeing technology uses 0% hazardous chemicals, saves 90% of CO2 emissions through on-site production, and reduces water consumption by 30% through the use of higher indigo concentrations. Furthermore, wastewater load is significantly reduced, and there is no health risk for workers.
NaturalReco: Microplastic-Free Sizing Agent
Another impressive feature is the NaturalReco technology developed by PureDenim. To protect the yarn during the weaving process, sizing agents are used to create a protective film around the yarn. Conventionally, polyvinyl alcohol (PVA)-based sizing agents are used. During industrial washing and laundry at home, PVAs are released in the form of microplastics, polluting the wastewater. NaturalReco replaces PVA with plant-based polymers (pectins) obtained from the waste of jam production (lemon peels) in Italy. This method protects the yarns during the weaving process and promotes the connection of the yarns without relying on harmful substances. This not only reduces the ecological footprint but also optimizes the use of natural resources and lowers CO2 emissions.
Eco Sonic: Ultrasound Finishing saving Water
The Eco Sonic technology is another milestone at PureDenim. This environmentally friendly finishing technique uses ultrasound waves to reduce the crocking (color transfer) of denim and desizes the fabric. This method uses cavitation effects to significantly reduce water consumption when washing denim fabric. This process requires only 0.53 liters of water per meter of fabric and 40% less energy than traditional methods.
Looking to the Future: Dyeing with Ultrasound
PureDenim’s continuous innovation is demonstrated by their latest project, which is currently in the prototype stage. Together with technology partner Sonovia, PureDenim has innovated their slasher dyeing line. Instead of up to 15 consecutive dye baths, the yarn is now dyed in a single dye bath using ultrasound technology. The cavitation effects are utilized to enhance color penetration into the yarn, enabling an 85% reduction in water consumption during the dyeing process.
Conclusion
The visit to PureDenim gave me a deep insight into the world of sustainable denim production. PureDenim proves that it is possible to produce high-quality denim without harming the environment. Their combination of traditional craftsmanship, cutting-edge technology, and a clear commitment to sustainability makes them a true pioneer in the denim industry.
