Want to buy a new coat or a pair of jeans? You might want to reconsider, because the fashion industry is not exactly sustainable, to say the least. ‘Less than one percent of the garments produced are recycled’, says Acerina Trejo Machín, Chief Technology Officer at Resortecs. ‘Most end up in landfills or are incinerated.’ This way of disposing used clothes leads to 1,2 billion tons CO2 and 34 million tons of waste each year. No wonder the textile industry is ranked within the top-5 of most polluting sectors in the world. 

The problem is largely due to the fact that it is very difficult to disassemble garments. ‘You need to separate the fabrics and other recyclable materials from non-recyclable components, like zippers, buttons and belts’, explains Trejo Machín. ‘Textile disassembly is either done manually, which is time consuming, expensive and not scalable, or mechanically, but that destroys the fibres and results in downcycling. So, there is not much motivation for the industry to change their ways.’ 

’Design-for-disassembly makes textile recycling easier’ 

Now Resortecs has come up with a solution that doesn’t leave you guilty when buying new clothes. Trejo Machín: ‘We enable the automatic disassembly of garments, thanks to our own sewing threads. Brands then design clothes for recycling from day one. This so-called design-for-disassembly gives us the opportunity to make textile recycling easier and accelerate fashion’s circular transition.’ 

Dissolving threads 

Resortecs has designed special heat-dissolvable threads that are called Smart Stitch™. These stitches are used to sew the different components on a pair of jeans, for example. At the end of life, the jeans can be dismantled easily and damage-free in Resortecs’ patented Smart Disassembly™-ovens. The recovered fabric can then be converted to new fibres, to produce new garments. Hence, the circle is completed. ‘The beauty of the technology is that there is no need to change anything in the production’, tells Trejo Machín. ‘You can just plug-and-play our Smart Stitch.’ 

The threads are made of polymers that are readily available on the market, like polyamides and polyolefins. Trejo Machín and colleagues then tweaked these molecules to get the best possible threads. ‘We have multiple Smart Stitch ranges, each with their own melting temperature, from 150 to 190 °C. This is necessary to ensure the usage of the garment is not affected. For example, that they will not melt during ironing, while guaranteeing the disassembly in our ovens.’ 

The original idea for these disappearing threads came from Resortecs CEO and founder Cédric Vanhoeck. He first came into contact with sustainability and circularity at Delft University of Technology, where he obtained his bachelor degree in industrial design engineering in 2013. Next, he studied marketing in Milan and fashion in Antwerpen. ‘Then he learned that the fashion industry wasn’t at all sustainable’, says Trejo Machín. ‘So, he combined his knowledge of sustainable engineering with fashion and came up with the concept of design-for-disassembly, which led to the founding of Resortecs in 2017.’ 

She herself joined the team about 1,5 years ago. ‘I was doing my PhD at the Luxembourg Institute of Science and Technology on sustainable methods for rubber applications. After graduating, I wanted to work for a company that was truly committed to creating a positive impact on the planet. I am happy to help this startup grow, while bringing the entire fashion industry one step closer to closing the loop.’ 

2000(0) pairs of jeans 

Recycling fabrics disassembled with Resortecs’ innovations offer a great way to reduce the negative environmental impact of the fashion industry, according to Trejo Machín. ‘Our life cycle analysis with a pair of jeans shows that combining our design-for-disassembly technology with the right kind of recycling can reduce the CO₂ emissions by up to 50 percent, waste generation by up to 80 percent and water use by up to 98 percent. If the entire European textile production were thermally disassembled and recycled, we would be able to avoid 60 million tons of CO₂ annually and save 2,3 billion euros.’ 

‘We already have collections with brands such as H&M and Decathlon’ 

But before we get there, the technology needs to be developed even further. The Smart Disassembly™ ovens now process 1 ton of clothes (the equivalent of 2000 pairs of jeans) per day. It is now a batch progress, where the ovens are opened and closed each run. ‘Our plan is to have a continuous line that can process up to 10 tons (or 20.000 pairs of jeans) a day at the end of 2023’, says Trejo Machín. ‘We already have collections with brands such as H&M and Decathlon. Within one year, we believe the number of brands using our solution will be even bigger.’  

The Resortecs-team is ambitious. Trejo Machín: ‘Our mission is to become the benchmark of circularity in clothes production. We think that recycling this way is the only logical thing to do to severely reduce the carbon footprint and pollution of the whole fashion industry.’